The human oral cavity contains a diverse ecosystem that is colonized by many microorganisms. Over time, a resident microbiota is established that typically remains stable throughout life. This microbiota includes bacteria, viruses and fungi that exist in complex biofilms. The makeup of the oral microbiota changes with age as different habitats form in the mouth. Imbalances in the normal microbiota have been linked to oral diseases as well as systemic conditions. Research continues to uncover relationships between the oral and total body microbiota and how they impact overall health.
The document discusses the ecology of the oral microbial flora. It describes the various ecological niches in the oral cavity like mucosal surfaces, teeth, and saliva that are colonized by different microbial species. The oral flora is acquired initially from the mother and environment then develops into a climax community as the individual is exposed to different microbes over time. A variety of factors like pH, nutrients, oxygen levels etc determine what bacteria can colonize different oral surfaces. The resident flora plays an important role in colonization resistance against pathogens.
The normal flora of the human body consists of microorganisms that colonize various areas without causing disease. The skin, nasal passages, mouth, intestines and genitourinary tract each have distinct resident microbial populations that help maintain health and defend against pathogens. These normal flora are mainly bacteria and include both commensal species that do not harm the host as well as mutualistic species that provide benefits like vitamin production.
The document discusses normal flora, which are microorganisms that inhabit healthy humans without causing disease. Resident flora establish themselves in a particular body site, while transient flora inhabit sites temporarily. Normal flora provide benefits like producing vitamins and protecting against pathogens, but can also cause harm if they spread to non-native sites or when the host's resistance is lowered. The types and distribution of normal flora vary depending on factors like age, sex, diet, and antibiotics.
Normal Microflora of Human Body. Dysbacteriosis. Prophylaxis & TreatmentEneutron
This document discusses the normal microflora of the human body, including the microflora of the skin, mouth, respiratory tract, gastrointestinal tract, urogenital tract, and other areas. It describes the roles and composition of the microflora in different parts of the body and at different life stages. The document also discusses dysbacteriosis, which is an imbalance in the normal microflora, and its causes, prevention, and treatment. Finally, it discusses gnotobiology, the study of microbe-free organisms, and how it has provided insights into the role of normal microflora.
The document discusses the oral microflora, including the different oral habitats that microorganisms inhabit, such as the teeth, oral mucosa, tongue, and saliva. It describes the various microorganisms commonly found in the oral cavity, including streptococci, actinomyces, and candida albicans. It also defines several terms related to oral microflora and their ecology.
Microbiology is the study of a variety of living things, such as bacteria, fungus, and other tiny creatures, that are not visible to the naked eye. However, these little creatures are the foundation of all life on earth.. all types of living things that are invisible to the unaided eye.
Important categories have been divided based on certain traits in the study of bacteria in food. These classifications have no taxonomic relevance.
Food technology, food safety and hygiene, food poisoning, food genomics, and, more generally,
This chapter discusses microbial ecology and biotechnology. It begins by defining microbial ecology as the study of relationships between microbes and their environment. Most human-microbe relationships are beneficial, such as our indigenous microflora that colonize our bodies. These microbes can have symbiotic relationships that are mutualistic, commensalistic, or parasitic. The chapter then describes the various microbes found in different parts of the human body like the skin, respiratory tract, and gastrointestinal tract. It discusses how biofilms form complex microbial communities and their medical significance. The chapter concludes by mentioning opportunistic pathogens and biotherapeutic agents that can affect our indigenous microflora, as well as synergistic infections caused by multiple microbes.
The document discusses normal flora and pathogenic bacteria that can infect surfaces in the body. It describes how different bacteria normally inhabit different body sites like the skin, oral cavity, intestines and urogenital tract. It also discusses sterile body sites. When bacteria spread from their normal sites and infect other surfaces, it can lead to diseases like endocarditis, osteomyelitis and prosthetic joint infections. Bacteria can form biofilms on surfaces, which makes surface infections difficult to treat.
The document discusses the ecology of the oral microbial flora. It describes the various ecological niches in the oral cavity like mucosal surfaces, teeth, and saliva that are colonized by different microbial species. The oral flora is acquired initially from the mother and environment then develops into a climax community as the individual is exposed to different microbes over time. A variety of factors like pH, nutrients, oxygen levels etc determine what bacteria can colonize different oral surfaces. The resident flora plays an important role in colonization resistance against pathogens.
The normal flora of the human body consists of microorganisms that colonize various areas without causing disease. The skin, nasal passages, mouth, intestines and genitourinary tract each have distinct resident microbial populations that help maintain health and defend against pathogens. These normal flora are mainly bacteria and include both commensal species that do not harm the host as well as mutualistic species that provide benefits like vitamin production.
The document discusses normal flora, which are microorganisms that inhabit healthy humans without causing disease. Resident flora establish themselves in a particular body site, while transient flora inhabit sites temporarily. Normal flora provide benefits like producing vitamins and protecting against pathogens, but can also cause harm if they spread to non-native sites or when the host's resistance is lowered. The types and distribution of normal flora vary depending on factors like age, sex, diet, and antibiotics.
Normal Microflora of Human Body. Dysbacteriosis. Prophylaxis & TreatmentEneutron
This document discusses the normal microflora of the human body, including the microflora of the skin, mouth, respiratory tract, gastrointestinal tract, urogenital tract, and other areas. It describes the roles and composition of the microflora in different parts of the body and at different life stages. The document also discusses dysbacteriosis, which is an imbalance in the normal microflora, and its causes, prevention, and treatment. Finally, it discusses gnotobiology, the study of microbe-free organisms, and how it has provided insights into the role of normal microflora.
The document discusses the oral microflora, including the different oral habitats that microorganisms inhabit, such as the teeth, oral mucosa, tongue, and saliva. It describes the various microorganisms commonly found in the oral cavity, including streptococci, actinomyces, and candida albicans. It also defines several terms related to oral microflora and their ecology.
Microbiology is the study of a variety of living things, such as bacteria, fungus, and other tiny creatures, that are not visible to the naked eye. However, these little creatures are the foundation of all life on earth.. all types of living things that are invisible to the unaided eye.
Important categories have been divided based on certain traits in the study of bacteria in food. These classifications have no taxonomic relevance.
Food technology, food safety and hygiene, food poisoning, food genomics, and, more generally,
This chapter discusses microbial ecology and biotechnology. It begins by defining microbial ecology as the study of relationships between microbes and their environment. Most human-microbe relationships are beneficial, such as our indigenous microflora that colonize our bodies. These microbes can have symbiotic relationships that are mutualistic, commensalistic, or parasitic. The chapter then describes the various microbes found in different parts of the human body like the skin, respiratory tract, and gastrointestinal tract. It discusses how biofilms form complex microbial communities and their medical significance. The chapter concludes by mentioning opportunistic pathogens and biotherapeutic agents that can affect our indigenous microflora, as well as synergistic infections caused by multiple microbes.
The document discusses normal flora and pathogenic bacteria that can infect surfaces in the body. It describes how different bacteria normally inhabit different body sites like the skin, oral cavity, intestines and urogenital tract. It also discusses sterile body sites. When bacteria spread from their normal sites and infect other surfaces, it can lead to diseases like endocarditis, osteomyelitis and prosthetic joint infections. Bacteria can form biofilms on surfaces, which makes surface infections difficult to treat.
The document discusses the human microbiome and normal microbial flora. It notes that a diverse microbial population normally inhabits human skin and mucous membranes. Germ-free animal studies showed that the normal flora substantially influences host well-being. Specific bacteria like Corynebacterium and Propionibacterium are prominent on the human body. The skin, respiratory tract, gastrointestinal tract, and urogenital tract each harbor distinct microbial populations. Pathogens have developed various virulence factors and mechanisms to invade and establish infection by avoiding the host immune system.
The document discusses various types of human microbiomes, including the oral microbiome, skin microbiome, respiratory tract microbiome, and gut microbiome. It describes the microorganisms commonly found in each area, such as various bacteria, archaea, fungi, and viruses. It also explains the important roles the microbiomes play in human health, such as aiding digestion, producing vitamins, supporting the immune system, and acting as a first line of defense against pathogens.
Normal flora refers to the microorganisms that normally inhabit various areas of the human body. There are two types of normal flora: resident flora that are always present, and transient flora that are temporary. Normal flora can have mutualistic or commensal relationships with the human body. Common sites inhabited by normal flora include the skin, conjunctiva, nasopharynx, oral cavity, gastrointestinal tract, and urogenital tract. The types of microbes found in these areas include various bacteria such as staphylococci and streptococci. Normal flora provides advantages to the human body by preventing pathogen growth and producing vitamins.
The document describes the normal flora of the human body. It states that normal flora are bacteria and fungi that normally inhabit several body sites, helping maintain health. Key body sites and their normal flora include the skin (e.g. Staphylococcus epidermidis), respiratory tract (e.g. viridans streptococci in the throat), and intestines (e.g. Firmicutes and Bacteroidetes in the colon). The normal flora protect against pathogens, aid nutrient absorption, and maintain a healthy balance when present.
The document discusses the normal microbial flora that inhabit healthy humans. It describes how the skin, mouth, intestines and other areas each have distinct resident and transient bacterial populations that protect against pathogens. The resident flora establishes itself and repopulates if disturbed, while the transient flora does not permanently colonize. These normal flora provide colonization resistance against infection and have important nutritional and protective functions. Figures show bacterial numbers by body site and mechanisms of pathogen competition.
The document discusses the human microbiome, specifically the urinary tract microbiome. It defines the human microbiota as the microbes found on and in the human body, which can vary between individuals due to factors like diet, age, and geography. The urinary tract is normally sterile, but the skin, mouth, nasal passages, and gut contain resident and transient bacteria that make up the normal flora. This flora plays an important role in health by preventing colonization by pathogens and producing vitamins, but under certain conditions bacteria from the normal flora can also cause disease. The vaginal flora typically contains Lactobacillus species that maintain acidity and prevent infections, while the gut flora aids in digestion and
The document discusses the microflora of the human body, including bacteria that form symbiotic relationships in the digestive system. It notes that microorganisms are present on the skin, in the mouth, respiratory tract and form the normal microflora that prevents pathogenic bacteria. The human flora includes bacteria, fungi and archaea that inhabit the body, some of which are useful while most have no known effect. The composition of the normal flora depends on factors like genetics, age and nutrition.
Microbiology is the study of microorganisms like bacteria, fungi and viruses. There are several branches of microbiology including bacteriology, mycology, virology and parasitology.
Bacteriology is the study of bacteria and their characteristics such as their cell structure, genetics and role in causing disease. Bacteria can be classified based on their shape, cell wall composition, mode of nutrition and respiration. They reproduce through binary fission.
Mycology is the study of fungi which have cell walls made of chitin. Fungi are classified based on their sexual reproduction and morphology. They can reproduce sexually through spores or asexually through budding or hyphal growth.
Viro
Oral microbiology/ rotary endodontic courses by indian dental academyIndian dental academy
Indian Dental Academy: will be one of the most relevant and exciting training center with best faculty and flexible training programs for dental professionals who wish to advance in their dental practice,Offers certified courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic Dentistry, Periodontics and General Dentistry.
This document provides an overview of microbiology. It defines microbiology as the study of microorganisms too small to be seen with the naked eye. It discusses that microorganisms are found everywhere and play important roles in processes like photosynthesis, biodegradation, and vitamin production. The document then reviews the history of microbiology, including early scientists like Hooke, Van Leeuwenhoek, Pasteur, and Koch. It also summarizes the classification of microorganisms into the three domains of Bacteria, Archaea, and Eucarya. The scope of microbiology is described as including both the basic study of microbes as well as their applied uses in fields like medicine, industry, and agriculture.
This document provides an introduction and overview of microbiology. It defines microbiology as the study of microorganisms too small to be seen with the naked eye. It discusses that microorganisms are found everywhere and play important roles in processes like photosynthesis, biodegradation, and vitamin production. The document then reviews the history of microbiology, including early pioneers like Hooke, Van Leeuwenhoek, Pasteur, and Koch. It also summarizes the classification of microorganisms into the three domains of Bacteria, Archaea, and Eucarya. The scope of microbiology is said to include both the basic study of microbes as well as their many applied uses.
Normal flora refers to the microorganisms that normally inhabit various areas of the human body without causing disease. The document discusses the different types and locations of normal flora, including bacteria commonly found on the skin, in the mouth, respiratory tract, urogenital tract, and gastrointestinal tract. It also outlines factors that influence the composition of normal flora such as age, diet, antibiotics, and environment.
The normal microflora that inhabit the human body outnumber human cells 10 to 1. These microorganisms play an important role in health, providing defense against pathogens, assisting digestion, and stimulating immune system development. Disruptions to the normal microflora can cause diseases like inflammatory bowel disease. The microflora is made up of resident and transient organisms. Resident flora reestablish themselves if disturbed and provide colonization resistance, while transient flora do not permanently establish. The microflora of different body sites varies and includes bacteria that benefit health as well as circumstances where microflora could cause disease.
This document discusses host-parasite relationships and how microorganisms enter the host. It defines key terms like host, parasite, pathogen, and virulence. It explains the different types of symbiotic relationships between organisms. The normal flora of different body sites is described, as well as the various entry points for microbes, including the skin/mucous membranes, mouth, respiratory tract, intestinal tract, and genitourinary tract. Different host defenses at each entry point help limit microbial invasion but infections can occur if pathogens can overcome these defenses.
Normal flora is the term used to describe the various bacteria and fungi that are permanent residents of certain
body sites, especially the skin, oropharynx, colon, and
vagina (Tables 6–1 and 6–2). Viruses and parasites (protozoa
and helminths), which are the other major groups of
microorganisms, are usually not considered members of
the normal flora, although they can be present in asymptomatic individuals. The normal flora organisms are often
referred to as commensals. Commensals are organisms
that derive benefit from another host but do not damage
that host. The term human microbiome is often used to
describe the normal flora.
The members of the normal flora play a role both in the
maintenance of health and in the causation of disease in
three significant ways:
(1) They can cause disease, especially in immunocompromised and debilitated individuals. Although these
organisms are nonpathogens in their usual anatomic location, they can be pathogens in other parts of the body.
(2) They constitute a protective host defense mechanism.
The nonpathogenic resident bacteria occupy attachment
sites on the skin and mucosa that can interfere with colonization by pathogenic bacteria. The ability of members of the
normal flora to limit the growth of pathogens is called colonization resistance. If the normal flora is suppressed, pathogens may grow and cause disease. For example, antibiotics
can reduce the normal colonic flora that allows Clostridium
difficile, which is resistant to the antibiotics, to overgrow and
cause pseudomembranous colitis.
(3) They may serve a nutritional function. The intestinal bacteria produce several B vitamins and vitamin K.
Poorly nourished people who are treated with oral antibiotics can have vitamin deficiencies as a result of the reduction in the normal flora. However, since germ-free animals
are well-nourished, the normal flora is not essential for
proper nutrition.
THE HUMAN MICROBIOME
The human microbiome is the term used to describe the
thousands of microbes (“microbiota”) located on the skin,
on mucosal surfaces, and within the lumen of the
TABLE 6–2 Medically Important Members of the Normal Flora
Location Important Organisms1 Less Important Organisms2
Skin Staphylococcus epidermidis Staphylococcus aureus, Corynebacterium (diphtheroids), various streptococci,
Pseudomonas aeruginosa, anaerobes (e.g., Propionibacterium), yeasts (e.g.,
Candida albicans)
Nose S. aureus3 S. epidermidis, Corynebacterium (diphtheroids), various streptococci
Mouth Viridans streptococci Various streptococci, Eikenella corrodens
Dental plaque Streptococcus mutans Prevotella intermedia, Porphyromonas gingivalis
Gingival crevices Various anaerobes (e.g.,
Bacteroides, Fusobacterium,
streptococci, Actinomyces)
Throat Viridans streptococci Various streptococci (including Streptococcus pyogenes and Streptococcus
pneumoniae), Neisseria species, Haemophilus influenzae, S. epidermidis
Colon Bacteroides fragilis, Escherichia
This document provides an overview of the normal flora found in various areas of the human body. It discusses the types of bacteria typically found in places like the skin, eyes, respiratory tract, gastrointestinal tract, and urogenital tract. It also covers the beneficial and harmful effects of normal flora, factors that can influence it, and how normal flora plays an important role in human health and physiology. Maintaining the balance of microbial ecosystems is crucial, as disruptions can have unpredictable consequences.
This document provides an overview of the microbiology of the oral cavity. It discusses the resident oral microflora including the major groups of microorganisms found, such as streptococci. Specifically, it focuses on the Streptococcus mutans group, detailing their role in dental caries, characteristics, ecology, physiology and screening tests. It also briefly discusses other streptococcal groups commonly found in the oral cavity like S. salivarius and S. milleri groups.
Эпидемический процесс – это процесс возникновения и распространения специфических инфекционных состояний (от бессимптомного носительства до манифестных заболеваний) на видовом и популяционном уровнях, то есть процесс взаимодействия двух популяций – популяции паразита и популяции хозяина (популяции людей). На эпидемический процесс большое влияние оказывают социальные условия жизни населения и природные факторы.
Наука, изучающая закономерности возникновения и распространения заболеваний различной этиологии среди населения с целью разработки профилактических мероприятий, называется эпидемиологией.
Эпидемический процесс имеет разное проявление:
- спорадическая заболеваемость – это низкий уровень заболеваемости данной инфекцией на данной территории в данный период (сезон) времени (единичные случаи заболеваний или групповые вспышки, не связанные между собой);
- эпидемия – это такой уровень заболеваемости данной инфекцией на данной территории в конкретный отрезок времени, который в несколько раз превышает уровень спорадической заболеваемости, прогрессирует по времени и имеет тенденцию к пространственному распространению;
- пандемия – это такой уровень заболеваемости данной инфекцией в конкретный отрезок времени, который не только резко превышает уровень обычных эпидемий, но и распространяется на территорию всей страны, территорию сопредельных государств, а иногда и многих стран.
В эпидемическом процессе выделяют следующие элементы: источник инфекции, резервуар возбудителя инфекции, механизмы, пути и факторы передачи инфекции, восприимчивый организм.
Источник инфекции – это организм человека или животного, в котором происходит размножение возбудителя, и от которого в дальнейшем заражается здоровый человек. От источника инфекции возбудитель проникает в организм здорового человека либо при непосредственном контакте, минуя фазу нахождения микроба во внешней среде, либо через объекты внешней среды и окружающие предметы. Основными источниками инфекции являются больной человек, больное животное, бактерионосители (люди, животные).
Резервуар возбудителя инфекции – это объекты внешней среды, которые являются естественной средой обитания некоторых возбудителей заболеваний человека (возбудители столбняка, легионеллеза) и в которых возбудитель находит благоприятные условия для своего роста и размножения (накопления). Основными резервуарами инфекции являются почва и вода. При некоторых заболеваниях природным резервуаром возбудителя инфекции называют источник инфекции, обеспечивающий сохранение в природе возбудителя как вида. Например, для чумы суслики, сурки, песчанки являются не только источником инфекции, но и природным резервуаром возбудителя.
This document discusses various types of symbiotic relationships between organisms, including parasitism, commensalism, and mutualism. It provides examples of each type of relationship. It also discusses the definitions and characteristics of hosts, parasites, normal flora, pathogens, toxins, and infections. The key types of symbiosis are defined as commensalism, mutualism, and parasitism. Commensalism benefits one organism without affecting the other. Mutualism benefits both organisms, while parasitism benefits the parasite at the expense of the host.
The document is an invitation to color and explore feelings using a Feelings Monster coloring book in the Reflect app. It asks the user to choose colors to express how different emotions like motivation, happiness, hurt, worry, and worthlessness are felt. The coloring book aims to help users learn about a range of emotions by expressing how scenarios or pictures in it make them feel through using different colors.
The document discusses the human microbiome and normal microbial flora. It notes that a diverse microbial population normally inhabits human skin and mucous membranes. Germ-free animal studies showed that the normal flora substantially influences host well-being. Specific bacteria like Corynebacterium and Propionibacterium are prominent on the human body. The skin, respiratory tract, gastrointestinal tract, and urogenital tract each harbor distinct microbial populations. Pathogens have developed various virulence factors and mechanisms to invade and establish infection by avoiding the host immune system.
The document discusses various types of human microbiomes, including the oral microbiome, skin microbiome, respiratory tract microbiome, and gut microbiome. It describes the microorganisms commonly found in each area, such as various bacteria, archaea, fungi, and viruses. It also explains the important roles the microbiomes play in human health, such as aiding digestion, producing vitamins, supporting the immune system, and acting as a first line of defense against pathogens.
Normal flora refers to the microorganisms that normally inhabit various areas of the human body. There are two types of normal flora: resident flora that are always present, and transient flora that are temporary. Normal flora can have mutualistic or commensal relationships with the human body. Common sites inhabited by normal flora include the skin, conjunctiva, nasopharynx, oral cavity, gastrointestinal tract, and urogenital tract. The types of microbes found in these areas include various bacteria such as staphylococci and streptococci. Normal flora provides advantages to the human body by preventing pathogen growth and producing vitamins.
The document describes the normal flora of the human body. It states that normal flora are bacteria and fungi that normally inhabit several body sites, helping maintain health. Key body sites and their normal flora include the skin (e.g. Staphylococcus epidermidis), respiratory tract (e.g. viridans streptococci in the throat), and intestines (e.g. Firmicutes and Bacteroidetes in the colon). The normal flora protect against pathogens, aid nutrient absorption, and maintain a healthy balance when present.
The document discusses the normal microbial flora that inhabit healthy humans. It describes how the skin, mouth, intestines and other areas each have distinct resident and transient bacterial populations that protect against pathogens. The resident flora establishes itself and repopulates if disturbed, while the transient flora does not permanently colonize. These normal flora provide colonization resistance against infection and have important nutritional and protective functions. Figures show bacterial numbers by body site and mechanisms of pathogen competition.
The document discusses the human microbiome, specifically the urinary tract microbiome. It defines the human microbiota as the microbes found on and in the human body, which can vary between individuals due to factors like diet, age, and geography. The urinary tract is normally sterile, but the skin, mouth, nasal passages, and gut contain resident and transient bacteria that make up the normal flora. This flora plays an important role in health by preventing colonization by pathogens and producing vitamins, but under certain conditions bacteria from the normal flora can also cause disease. The vaginal flora typically contains Lactobacillus species that maintain acidity and prevent infections, while the gut flora aids in digestion and
The document discusses the microflora of the human body, including bacteria that form symbiotic relationships in the digestive system. It notes that microorganisms are present on the skin, in the mouth, respiratory tract and form the normal microflora that prevents pathogenic bacteria. The human flora includes bacteria, fungi and archaea that inhabit the body, some of which are useful while most have no known effect. The composition of the normal flora depends on factors like genetics, age and nutrition.
Microbiology is the study of microorganisms like bacteria, fungi and viruses. There are several branches of microbiology including bacteriology, mycology, virology and parasitology.
Bacteriology is the study of bacteria and their characteristics such as their cell structure, genetics and role in causing disease. Bacteria can be classified based on their shape, cell wall composition, mode of nutrition and respiration. They reproduce through binary fission.
Mycology is the study of fungi which have cell walls made of chitin. Fungi are classified based on their sexual reproduction and morphology. They can reproduce sexually through spores or asexually through budding or hyphal growth.
Viro
Oral microbiology/ rotary endodontic courses by indian dental academyIndian dental academy
Indian Dental Academy: will be one of the most relevant and exciting training center with best faculty and flexible training programs for dental professionals who wish to advance in their dental practice,Offers certified courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic Dentistry, Periodontics and General Dentistry.
This document provides an overview of microbiology. It defines microbiology as the study of microorganisms too small to be seen with the naked eye. It discusses that microorganisms are found everywhere and play important roles in processes like photosynthesis, biodegradation, and vitamin production. The document then reviews the history of microbiology, including early scientists like Hooke, Van Leeuwenhoek, Pasteur, and Koch. It also summarizes the classification of microorganisms into the three domains of Bacteria, Archaea, and Eucarya. The scope of microbiology is described as including both the basic study of microbes as well as their applied uses in fields like medicine, industry, and agriculture.
This document provides an introduction and overview of microbiology. It defines microbiology as the study of microorganisms too small to be seen with the naked eye. It discusses that microorganisms are found everywhere and play important roles in processes like photosynthesis, biodegradation, and vitamin production. The document then reviews the history of microbiology, including early pioneers like Hooke, Van Leeuwenhoek, Pasteur, and Koch. It also summarizes the classification of microorganisms into the three domains of Bacteria, Archaea, and Eucarya. The scope of microbiology is said to include both the basic study of microbes as well as their many applied uses.
Normal flora refers to the microorganisms that normally inhabit various areas of the human body without causing disease. The document discusses the different types and locations of normal flora, including bacteria commonly found on the skin, in the mouth, respiratory tract, urogenital tract, and gastrointestinal tract. It also outlines factors that influence the composition of normal flora such as age, diet, antibiotics, and environment.
The normal microflora that inhabit the human body outnumber human cells 10 to 1. These microorganisms play an important role in health, providing defense against pathogens, assisting digestion, and stimulating immune system development. Disruptions to the normal microflora can cause diseases like inflammatory bowel disease. The microflora is made up of resident and transient organisms. Resident flora reestablish themselves if disturbed and provide colonization resistance, while transient flora do not permanently establish. The microflora of different body sites varies and includes bacteria that benefit health as well as circumstances where microflora could cause disease.
This document discusses host-parasite relationships and how microorganisms enter the host. It defines key terms like host, parasite, pathogen, and virulence. It explains the different types of symbiotic relationships between organisms. The normal flora of different body sites is described, as well as the various entry points for microbes, including the skin/mucous membranes, mouth, respiratory tract, intestinal tract, and genitourinary tract. Different host defenses at each entry point help limit microbial invasion but infections can occur if pathogens can overcome these defenses.
Normal flora is the term used to describe the various bacteria and fungi that are permanent residents of certain
body sites, especially the skin, oropharynx, colon, and
vagina (Tables 6–1 and 6–2). Viruses and parasites (protozoa
and helminths), which are the other major groups of
microorganisms, are usually not considered members of
the normal flora, although they can be present in asymptomatic individuals. The normal flora organisms are often
referred to as commensals. Commensals are organisms
that derive benefit from another host but do not damage
that host. The term human microbiome is often used to
describe the normal flora.
The members of the normal flora play a role both in the
maintenance of health and in the causation of disease in
three significant ways:
(1) They can cause disease, especially in immunocompromised and debilitated individuals. Although these
organisms are nonpathogens in their usual anatomic location, they can be pathogens in other parts of the body.
(2) They constitute a protective host defense mechanism.
The nonpathogenic resident bacteria occupy attachment
sites on the skin and mucosa that can interfere with colonization by pathogenic bacteria. The ability of members of the
normal flora to limit the growth of pathogens is called colonization resistance. If the normal flora is suppressed, pathogens may grow and cause disease. For example, antibiotics
can reduce the normal colonic flora that allows Clostridium
difficile, which is resistant to the antibiotics, to overgrow and
cause pseudomembranous colitis.
(3) They may serve a nutritional function. The intestinal bacteria produce several B vitamins and vitamin K.
Poorly nourished people who are treated with oral antibiotics can have vitamin deficiencies as a result of the reduction in the normal flora. However, since germ-free animals
are well-nourished, the normal flora is not essential for
proper nutrition.
THE HUMAN MICROBIOME
The human microbiome is the term used to describe the
thousands of microbes (“microbiota”) located on the skin,
on mucosal surfaces, and within the lumen of the
TABLE 6–2 Medically Important Members of the Normal Flora
Location Important Organisms1 Less Important Organisms2
Skin Staphylococcus epidermidis Staphylococcus aureus, Corynebacterium (diphtheroids), various streptococci,
Pseudomonas aeruginosa, anaerobes (e.g., Propionibacterium), yeasts (e.g.,
Candida albicans)
Nose S. aureus3 S. epidermidis, Corynebacterium (diphtheroids), various streptococci
Mouth Viridans streptococci Various streptococci, Eikenella corrodens
Dental plaque Streptococcus mutans Prevotella intermedia, Porphyromonas gingivalis
Gingival crevices Various anaerobes (e.g.,
Bacteroides, Fusobacterium,
streptococci, Actinomyces)
Throat Viridans streptococci Various streptococci (including Streptococcus pyogenes and Streptococcus
pneumoniae), Neisseria species, Haemophilus influenzae, S. epidermidis
Colon Bacteroides fragilis, Escherichia
This document provides an overview of the normal flora found in various areas of the human body. It discusses the types of bacteria typically found in places like the skin, eyes, respiratory tract, gastrointestinal tract, and urogenital tract. It also covers the beneficial and harmful effects of normal flora, factors that can influence it, and how normal flora plays an important role in human health and physiology. Maintaining the balance of microbial ecosystems is crucial, as disruptions can have unpredictable consequences.
This document provides an overview of the microbiology of the oral cavity. It discusses the resident oral microflora including the major groups of microorganisms found, such as streptococci. Specifically, it focuses on the Streptococcus mutans group, detailing their role in dental caries, characteristics, ecology, physiology and screening tests. It also briefly discusses other streptococcal groups commonly found in the oral cavity like S. salivarius and S. milleri groups.
Эпидемический процесс – это процесс возникновения и распространения специфических инфекционных состояний (от бессимптомного носительства до манифестных заболеваний) на видовом и популяционном уровнях, то есть процесс взаимодействия двух популяций – популяции паразита и популяции хозяина (популяции людей). На эпидемический процесс большое влияние оказывают социальные условия жизни населения и природные факторы.
Наука, изучающая закономерности возникновения и распространения заболеваний различной этиологии среди населения с целью разработки профилактических мероприятий, называется эпидемиологией.
Эпидемический процесс имеет разное проявление:
- спорадическая заболеваемость – это низкий уровень заболеваемости данной инфекцией на данной территории в данный период (сезон) времени (единичные случаи заболеваний или групповые вспышки, не связанные между собой);
- эпидемия – это такой уровень заболеваемости данной инфекцией на данной территории в конкретный отрезок времени, который в несколько раз превышает уровень спорадической заболеваемости, прогрессирует по времени и имеет тенденцию к пространственному распространению;
- пандемия – это такой уровень заболеваемости данной инфекцией в конкретный отрезок времени, который не только резко превышает уровень обычных эпидемий, но и распространяется на территорию всей страны, территорию сопредельных государств, а иногда и многих стран.
В эпидемическом процессе выделяют следующие элементы: источник инфекции, резервуар возбудителя инфекции, механизмы, пути и факторы передачи инфекции, восприимчивый организм.
Источник инфекции – это организм человека или животного, в котором происходит размножение возбудителя, и от которого в дальнейшем заражается здоровый человек. От источника инфекции возбудитель проникает в организм здорового человека либо при непосредственном контакте, минуя фазу нахождения микроба во внешней среде, либо через объекты внешней среды и окружающие предметы. Основными источниками инфекции являются больной человек, больное животное, бактерионосители (люди, животные).
Резервуар возбудителя инфекции – это объекты внешней среды, которые являются естественной средой обитания некоторых возбудителей заболеваний человека (возбудители столбняка, легионеллеза) и в которых возбудитель находит благоприятные условия для своего роста и размножения (накопления). Основными резервуарами инфекции являются почва и вода. При некоторых заболеваниях природным резервуаром возбудителя инфекции называют источник инфекции, обеспечивающий сохранение в природе возбудителя как вида. Например, для чумы суслики, сурки, песчанки являются не только источником инфекции, но и природным резервуаром возбудителя.
This document discusses various types of symbiotic relationships between organisms, including parasitism, commensalism, and mutualism. It provides examples of each type of relationship. It also discusses the definitions and characteristics of hosts, parasites, normal flora, pathogens, toxins, and infections. The key types of symbiosis are defined as commensalism, mutualism, and parasitism. Commensalism benefits one organism without affecting the other. Mutualism benefits both organisms, while parasitism benefits the parasite at the expense of the host.
The document is an invitation to color and explore feelings using a Feelings Monster coloring book in the Reflect app. It asks the user to choose colors to express how different emotions like motivation, happiness, hurt, worry, and worthlessness are felt. The coloring book aims to help users learn about a range of emotions by expressing how scenarios or pictures in it make them feel through using different colors.
/fhfhsghsgfgjjsfjrsthusthhnfdgfghndrtjheayhHFGNRSHSRTHSRTHAEHEHJNHFHETHSETHJSRJRSJHEATHFGHdfngfjnhmtghmxmghmhgmjjfegkjbgkj.njnljdfgkljgfkljnfgbldfngldfglljgnhlej;glaeglejhnglaeghalhlg;aehg;laehrg;lehnglndgl/.ernahg'kjnb.l;aekng;leknalvvngolaewhglnablnea;olgnlfdnvbrl/eng;/lenlvblngbreagejnrlbn;erahg'argnlbknea;rgh'p;hrg'oWHG'RHIG'Wg'wpnblknsblvjkgvlowerhg'wphklgvHG"iophgpknbLKghpknfp'vbghpngbeaghshbsetrhkbgkejrgkjlwgfklwejglkwejgtflwekgkewugfkluwgflEKLUWEGBFLUKWEGLKJWEGBFLKWJEGBKJLWEGFKLWegkljwegwGJKEfwelkgflkwegklweghghwkjegh;wehgkwejhgwkehglwkEHKWEGHWKHWKEHGKJWEHGKJWEHGKWJHLWHGKJGWKJFEJKDSFBSDFBFHBSDFM,BSFBSDFSDFBMSDFMBSDFBNSDBSDFMBSDFBNSDFBNDSFBNSDFNBNB NDFDFJBNFDBNFDNbndfmndfmndfnbdfbndfbndfnfdndfndfbnfdnmfdnmfdmnmnfdmmnfdmndfmnnmfddm,fdmnfdmndfnmnmfdnmdfmndfmnmnfdnmdfmnfdmndfnnmdfndfnmdfnf,fbdsbfsdfjhsdfjhsdgflhgskflgsldkjfglkdfglkjgsdfkglkgflskjgdflksgfskdlglkjfglksfgklsfglskfjlskjdflskjgfkjfkjgfd Иллюстрированное учебное пособие “Общая микробиология” подготовлено в качестве информационного сопровождения самостоятельной работы студентов, осваивающих основные образовательные программы высшего профессионального образования укрупненной группы специальностей 060000 – Здравоохранение, разработанные на основе ФГОС и предусматривающие формирование знаний по микробиологии и вирусологии. В иллюстрированном учебном пособии приводятся сведения по морфологии, физиологии, генетике, экологии микроорганизмов, основам инфектологии и эпидемиологии инфекционных болезней. Каждый раздел сопровождается контрольными вопросами и тренировочным тестами. Пособие содержит также методические указания по проведению практических занятий по общей микробиологии. Иллюстрированное учебное пособие предназначено для внеаудиторной подготовки студентов, обучающихся по специальностям 060101 (лечебное дело), 060103 (педиатрия), 060105 (медико-профилактическое дело), 060201 (стоматология) и 060301 (фармация). Эпидемический процесс – это процесс возникновения и распространения специфических инфекционных состояний (от бессимптомного носительства до манифестных заболеваний) на видовом и популяционном уровнях, то есть процесс взаимодействия двух популяций – популяции паразита и популяции хозяина (популяции людей). На эпидемический процесс большое влияние оказывают социальные условия жизни населения и природные факторы.
Наука, изучающая закономерности возникновения и распространения заболеваний различной этиологии среди населения с целью разработки профилактических мероприятий, называется эпидемиологией.
Эпидемический процесс имеет разное проявление:
- спорадическая заболеваемость – это низкий уровень заболеваемости данной инфекцией на данной территории в данный период (сезон) времени (единичные случаи заболеваний или групповые вспышки, не связанные между собой);
- эпидемия – это такой уровень заболеваемости данной инфекцией на данной территории в конкретный отрезок времени, который в несколько раз превышает уровень спорадической заболеваемости, прогрессирует по времени и имеет тенд
This document discusses various dental and oral diseases, their causes, and the microorganisms involved. It describes odontogenic infections which can develop from issues like untreated caries or pulpitis. These infections may remain localized or spread systemically. Key microbes involved include streptococci, staphylococci, and various anaerobes. It also discusses specific conditions like dental caries, pulpitis, periodontitis, periostitis, osteomyelitis, and abscesses. Oral fungal infections especially candidiasis are explained in detail along with symptoms and types. Ulcerative necrotic gingivostomatitis is also summarized.
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
Here is the updated list of Top Best Ayurvedic medicine for Gas and Indigestion and those are Gas-O-Go Syp for Dyspepsia | Lavizyme Syrup for Acidity | Yumzyme Hepatoprotective Capsules etc
Basavarajeeyam is a Sreshta Sangraha grantha (Compiled book ), written by Neelkanta kotturu Basavaraja Virachita. It contains 25 Prakaranas, First 24 Chapters related to Rogas& 25th to Rasadravyas.
Muktapishti is a traditional Ayurvedic preparation made from Shoditha Mukta (Purified Pearl), is believed to help regulate thyroid function and reduce symptoms of hyperthyroidism due to its cooling and balancing properties. Clinical evidence on its efficacy remains limited, necessitating further research to validate its therapeutic benefits.
TEST BANK For Community Health Nursing A Canadian Perspective, 5th Edition by...Donc Test
TEST BANK For Community Health Nursing A Canadian Perspective, 5th Edition by Stamler, Verified Chapters 1 - 33, Complete Newest Version Community Health Nursing A Canadian Perspective, 5th Edition by Stamler, Verified Chapters 1 - 33, Complete Newest Version Community Health Nursing A Canadian Perspective, 5th Edition by Stamler Community Health Nursing A Canadian Perspective, 5th Edition TEST BANK by Stamler Test Bank For Community Health Nursing A Canadian Perspective, 5th Edition Pdf Chapters Download Test Bank For Community Health Nursing A Canadian Perspective, 5th Edition Pdf Download Stuvia Test Bank For Community Health Nursing A Canadian Perspective, 5th Edition Study Guide Test Bank For Community Health Nursing A Canadian Perspective, 5th Edition Ebook Download Stuvia Test Bank For Community Health Nursing A Canadian Perspective, 5th Edition Questions and Answers Quizlet Test Bank For Community Health Nursing A Canadian Perspective, 5th Edition Studocu Test Bank For Community Health Nursing A Canadian Perspective, 5th Edition Quizlet Test Bank For Community Health Nursing A Canadian Perspective, 5th Edition Stuvia Community Health Nursing A Canadian Perspective, 5th Edition Pdf Chapters Download Community Health Nursing A Canadian Perspective, 5th Edition Pdf Download Course Hero Community Health Nursing A Canadian Perspective, 5th Edition Answers Quizlet Community Health Nursing A Canadian Perspective, 5th Edition Ebook Download Course hero Community Health Nursing A Canadian Perspective, 5th Edition Questions and Answers Community Health Nursing A Canadian Perspective, 5th Edition Studocu Community Health Nursing A Canadian Perspective, 5th Edition Quizlet Community Health Nursing A Canadian Perspective, 5th Edition Stuvia Community Health Nursing A Canadian Perspective, 5th Edition Test Bank Pdf Chapters Download Community Health Nursing A Canadian Perspective, 5th Edition Test Bank Pdf Download Stuvia Community Health Nursing A Canadian Perspective, 5th Edition Test Bank Study Guide Questions and Answers Community Health Nursing A Canadian Perspective, 5th Edition Test Bank Ebook Download Stuvia Community Health Nursing A Canadian Perspective, 5th Edition Test Bank Questions Quizlet Community Health Nursing A Canadian Perspective, 5th Edition Test Bank Studocu Community Health Nursing A Canadian Perspective, 5th Edition Test Bank Quizlet Community Health Nursing A Canadian Perspective, 5th Edition Test Bank Stuvia
Integrating Ayurveda into Parkinson’s Management: A Holistic ApproachAyurveda ForAll
Explore the benefits of combining Ayurveda with conventional Parkinson's treatments. Learn how a holistic approach can manage symptoms, enhance well-being, and balance body energies. Discover the steps to safely integrate Ayurvedic practices into your Parkinson’s care plan, including expert guidance on diet, herbal remedies, and lifestyle modifications.
Local Advanced Lung Cancer: Artificial Intelligence, Synergetics, Complex Sys...Oleg Kshivets
Overall life span (LS) was 1671.7±1721.6 days and cumulative 5YS reached 62.4%, 10 years – 50.4%, 20 years – 44.6%. 94 LCP lived more than 5 years without cancer (LS=2958.6±1723.6 days), 22 – more than 10 years (LS=5571±1841.8 days). 67 LCP died because of LC (LS=471.9±344 days). AT significantly improved 5YS (68% vs. 53.7%) (P=0.028 by log-rank test). Cox modeling displayed that 5YS of LCP significantly depended on: N0-N12, T3-4, blood cell circuit, cell ratio factors (ratio between cancer cells-CC and blood cells subpopulations), LC cell dynamics, recalcification time, heparin tolerance, prothrombin index, protein, AT, procedure type (P=0.000-0.031). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and N0-12 (rank=1), thrombocytes/CC (rank=2), segmented neutrophils/CC (3), eosinophils/CC (4), erythrocytes/CC (5), healthy cells/CC (6), lymphocytes/CC (7), stick neutrophils/CC (8), leucocytes/CC (9), monocytes/CC (10). Correct prediction of 5YS was 100% by neural networks computing (error=0.000; area under ROC curve=1.0).
Basavarajeeyam is an important text for ayurvedic physician belonging to andhra pradehs. It is a popular compendium in various parts of our country as well as in andhra pradesh. The content of the text was presented in sanskrit and telugu language (Bilingual). One of the most famous book in ayurvedic pharmaceutics and therapeutics. This book contains 25 chapters called as prakaranas. Many rasaoushadis were explained, pioneer of dhatu druti, nadi pareeksha, mutra pareeksha etc. Belongs to the period of 15-16 century. New diseases like upadamsha, phiranga rogas are explained.
- Video recording of this lecture in English language: https://youtu.be/kqbnxVAZs-0
- Video recording of this lecture in Arabic language: https://youtu.be/SINlygW1Mpc
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
2. Microbes appear in every
corner of human life, and
microbes affect every aspect
of human life. The human
oral cavity contains a number
of different habitats. Synergy
and interaction of variable
oral microorganisms help
human body against invasion
of undesirable stimulation
outside. However, imbalance
of microbial flora contributes
to oral diseases and systemic
diseases. Oral microbiomes
play an important role in the
human microbial community
and human health.
3. The oral cavity is a border area between the environment and the human organism, a gateway for food, an outpost of the
immune system and above all a multilayered habitat inhabited by countless microorganisms.
The mouth is continually exposed to organisms from the external environment ,beginning with the passage through the
birth canal.
In time a ecological balance is reached that serves to establish a resident microbial flora that remains fairly stable
throughout life.
Microorganisms in mouth were first described by Anton von Leeuwenhoek in 1683.
4. HISTORY
Louis Pasteur – Father of Microbiology
Antony Van Leeuwenhook in 16th century identified bacteria and its shapes
– rods , cocci and spiral forms .
Willoughby D. Miller proposed that carbohydrate from food were broken
down by oral bacteria and the resulting acids caused dissolution of the
enamel .
Pierre Fauchard in 1745 described tartar and plaque .
J.K. Clark in 1942 identified coccus from carious lesion and named as
Streptococcus mutans
5. The discovery of microbes dates back to the 1700 y.
Historically, Antonie van Leeuwenhoek peered and
examined dental plaque sampled from himself and others
through his microscope. His sense of awe and his early
appreciation of the diversity our microbial partners were
evident. He named the microbes “Dierken”, meaning
small lively objects.
The human oral cavity contains a number of different
habitats, including the teeth, gingival sulcus, tongue, hard
and soft palates, and tonsils, and acts the tube which
connect the outside and the digestive tract and respiratory
tract of human body, which provides the appropriate
space for the colonization of microorganisms. The
microorganisms found in the human oral cavity have
been referred to as the oral microflora, oral microbiota,
or oral microbiome.
6.
7. Ecology
• Ecology (from Greek) is the scientific study of
interactions among organisms and their environment,
such as the interactions organisms have with each
other and with their abiotic environment; The
ecosystem is composed of microbial communities
living on specific sites surrounded by a different
physical and chemical elements.
8. Ecosystems
• Ecosystems are composed of dynamically interacting
parts including organisms, the communities they make
up, and the non-living components of their
environment; Ecosystem processes, such as primary
production, nutrient cycling, and various niche
construction activities, regulate the flux of energy and
matter through an environment.
9. Microflora
•Living microorganisms that are so small that
they can be seen only with a microscope and
that maintain a more or less constant
presence in a particular area;
•Includes bacteria, viruses, protozoa, fungi.
10. Oral microflora
• Oral microflora refers to the community of microorganisms
coexisting in the oral cavity as its primary habitat;
• These strains of bacteria colonize the various different
surfaces present in the oral cavity, and communicate between
each other through complex cell signaling processes;
• The body’s own defenses also play a role in maintaining a
balance and ensuring a healthy oral environment.
11. Normal - resident flora
In a healthy body, the internal tissues - blood, brain, muscle,
etc., are normally free of microorganisms;
However, the surface tissues - skin and mucous membranes,
are constantly in contact with environmental organisms and
become readily colonized by various microbial species;
The mixture of organisms regularly found at any anatomical
site is referred to as the normal flora or resident flora, some
researchers prefer the term "indigenous microbiota".
12. Resident microflora Typical microflora of a
econiche;
Microorganisms are separated and grouped
according to the different conditions of life;
Resident microflora has an important function
in host:
Digestive and nutritional;
Competition with pathogenic microflora.
13. Transient Microbiota Transient microbes are
just passing through;
Although they may attempt to colonize the same areas
of the body as do resident microbiota, transients are
unable to remain in the body for extended periods of
time due to:
Competition from resident microbes;
Elimination by the body’s immune system;
Physical or chemical changes within the body that
discourage the growth of transient microbes.
14. Opportunistic microbes
Under normal conditions, resident and transient microbes cause the host no harm;
However, if the opportunity arises, some of these microbes are able to cause disease
and become opportunistic pathogens.
This can happen due to a number of different conditions:
When the immune system isn’t working properly, normal flora can overpopulate or
move into areas of the body where they do not normally occur;
When the balance of normal microbes is disrupted, for example when a person takes
broad spectrum antibiotics, microbes that are normally crowded out by resident
microbes have an opportunity to take over;
Disease can result when normal flora are traumatically introduced to an area of the
body that they do not normally occur in.
15. Endogenous microflora
That is microflora already present in the
body, but has previously been inapparent or
dormant.
Bacterial flora is endogenous bacteria, which
is defined as bacteria that naturally reside in a
closed system.
16. Exogenous microflora
Exogenous bacteria are microorganisms introduced to closed biological
systems from the external world;
They exist in aquatic and terrestrial environments, as well as the
atmosphere;
Microorganisms in the external environment have existed on Earth for
3.5 billion years;
Exogenous bacteria can be either benign or pathogenic.
17. The origin of Oral Microflora
The microflora present in our mouths is acquired from birth, as newborn
babies have no bacteria in their mouths;
Over time, the oral cavity becomes colonized by the strains of bacteria
that eventually form the resident microflora, which establish a
permanent population in the mouth;
Over time as the individual is further exposed to external sources of
bacteria, the biodiversity of the oral cavity increases, to a point where
stability is reached.
This is termed the climax community.
18. The source of microorganisms
• The source of these microorganisms mainly comes from saliva, although it
also includes the food and water consumed by the individual;
• This process takes place within the first few hours of life;
• Majority of children obtain their resident microflora from their mothers, as
they often possess identical strains of bacteria;
• This is known as vertical transmission;
• Horizontal transmission also takes place as children interact with their
peers, and later in life between spouses and partners.
• Streptococcus salivarius is dominant and may make up 98% of the total oral
flora until the appearance of the teeth (6 - 9 months in humans).
19. Periods of formation of the oral ecosystem
The neonatal period:
Mostly aerobes;
Candida albicans - 54%;
Obtained from the mother and the surrounding area;
Period before eruption:
Facultative anaerobes and anaerobes;
Streptococcus - 90%;
Actinomyces;
Candida albicans.
After eruption
The eruption of the teeth during the first year leads to colonization by S. mutans and S. sanguis;
These bacteria require a nondesquamating (nonepithelial) surface in order to colonize;
They will persist as long as teeth remain;
Other strains of streptococci adhere strongly to the gums and cheeks but not to the teeth.
20. Variations in Microflora
Everyone has microflora, but it varies between
people depending on the condition of their oral
cavity;
Not all individuals would have the same
microflora profile;
Not all bacteria are ubiquitous in all individuals.
21. DEFINITIONS:
• Commensal: An organism living in/on an organism of another species without
injuring the host;
• Parasite: An organism living in/on and at the expense of another organism (the
host). Equivalent to a pathogen;
• Opportunistic Pathogen: A commensal organism that can cause disease in certain
circumstances ;
• Symbiosis: The mutually beneficial association between two organisms ;
• Aerobic Organism: requiring oxygen for growth and replication;
• Anaerobe: Organism that grows and replicates in the absence of oxygen; not
necessarily killed by oxygen;
• Strict anaerobe: Anaerobe killed by oxygen;
• Facultative anaerobe: Organism capable of growth and replication in the presence
or absence of oxygen;
22. Important Oral Bacteria
Gram Positive organisms:
• Rods (bacilli), cocci or irregular shape (pleomorphic);
• Oxygen tolerance varies from aerobes to strict anaerobes;
• Most are fermentative;
• Cell wall has thick peptidoglycan layer (penicillin has effect by interfering
production of this layer).
Streptococci: Isolated from all sights of the mouth;
Large proportion of resident microflora;
Majority α-haemolytic.
23. Strep mutans: Associated with caries;
Associated with bacterial endocarditis.
Streptococcus mutans.
Streptococcus mutans is the primary bacterium involved in plaque formation
and initiation of dental caries;
Viewed as an opportunistic infection, dental disease is one of the most
prevalent and costly infectious diseases
Strep salivarius:
Colonise mucosal surfaces especially the tongue.
Strep angiosus: Isolated dental plaque & mucosal surfaces;
Seen in maxillofacial infections, brain, liver etc.
24. Actinomyces, facultative anaerobe;
• Lactobacillus, produce lactic acid, facultative anaerobe, role
in dentine caries rather than enamel caries;
• Streptococcus facultative anaerobic cocci, produce lactic acid
some implicated in caries.
Lactobacillus species
Lactobacilli in the oral cavity probably contribute to acid
formation that leads to dental caries.
25. Biofilm formation
Biofilms usually occur when one bacterial species attaches specifically or non
specifically to a surface, and then secretes carbohydrate slime (exopolymer)
that imbeds the bacteria and attracts other microbes to the biofilm for
protection or nutritional advantages.
Biofilm
The classic biofilm that involves components of the normal flora of the oral
cavity is the formation of dental plaque on the teeth;
Plaque is a naturally-constructed biofilm, in which the consortia of bacteria
may reach a thickness of cells on the surfaces of the teeth;
These accumulations subject the teeth and gingival tissues to high
concentrations of bacterial metabolites, which result in dental disease.
27. Oral flora changes with age. Time during a lifetime
MAJOR COMPONENTS & CHANGES IN ORAL FLORA
Newborn
Oral cavity sterile. Soon colonised by facultative and aerobic organisms; esp S. salivarius
6 months
Flora becomes more complex & includes anaerobic orgs eg. Veillonella sp. & Fusobacteria
Tooth eruption
Increase in complexity. S sanguis, S mutans and A viscosus appear. New habitats include hard
surfaces and gingival crevice.
Child to adult
Various anaerobes frequently found inc. Members of the Bacteroidaceae. Spirochaetes isolated more
frequently
Loss of teeth
Disappearance of S mutan, S sanguis, spirochaetes and many anaerobes
Dentures etc
Reappearance of bacteria able to grow on hard surfaces.
28. Regulation of oral microbiota on systematic
diseases
•Oral microbiota is related to oral and
systematic diseases. Oral microbiota is
altered during oral and whole body diseases.
Thus, oral microbiota will be a new target
for treating oral diseases and improving the
body’s physical state.