1. Herpesviridae is a family of viruses that cause diseases in humans and animals through latent and lytic infections. Important members include HSV-1, HSV-2, VZV, EBV, CMV, HHV-6, and HHV-7.
2. These viruses have been studied extensively since ancient times, with advances in understanding their transmission and diseases in the 1920s-1950s. They enter through skin or mucous membrane defects and can cause various infections.
3. Latent infections establish in ganglia or lymphoid tissues, and reactivation can cause recurrent lesions or diseases. Diagnosis involves microscopy, cell culture, antigen detection and molecular methods. Treatment
The Epstein–Barr virus (EBV), also called human herpesvirus 4 (HHV-4), is one of eight known human herpesvirus types in the herpes family, and is one of the most common viruses in humans.
herpes simplex virus is a double stranded DNA virus causing many symptoms all over the body. it affects globally all over the world .
neonatal hsv attacks even the baby and made them to a fatal conditions.
The Paramyxoviridae is a family of single-stranded RNA viruses known to cause different types of infections in vertebrates. Examples of these infections in humans include the measles virus, mumps virus, parainfluenza virus, and respiratory syncytial virus (RSV).
Polio: flaccid paralysis, major and minor
disease, fecal-oral
Coxsackievirus A: vesicular diseases,
meningitis; coxsackievirus B (body):
pleurodynia, myocarditis
Other echovirus and enteroviruses: like
coxsackievirus
Rhinoviruses: common cold, acid labile, does
not replicate above 33° C
Biology, Virulence, and Disease
• Small size, icosahedral capsid, positive RNA
genome with terminal protein
• Genome is sufficient for infection
• Encodes RNA-dependent RNA polymerase,
replicates in cytoplasm
Enteroviruses
• Capsid virus resistant to inactivation
• Disease due to lytic infection of important
target tissue
• Polio: cytolytic infection of motor neurons of
anterior horn and brainstem, paralysis
• Coxsackievirus A: herpangina, hand-foot-
and-mouth disease, common cold,
meningitis
• Coxsackievirus B: pleurodynia, neonatal
myocarditis, type 1 diabetes
Rhinoviruses
• Acid labile and cannot replicate at body
temperature
• Restricted to upper respiratory tract
• Common cold
Epidemiology
• Enteroviruses transmitted by fecal-oral route
and aerosols
• Rhinoviruses transmitted by aerosols and
contact
Diagnosis
• Immune assays (ELISA) or RT-PCR genome
analysis of blood, CSF, or other relevant
sample
Treatment, Prevention, and Control
• OPV and IPV polio vaccines
P
icornaviridae is one of the largest families of viruses and
includes some of the most important human and animal
viruses (Box 46-1). As the name indicates, these viruses are
small (pico) ribonucleic acid (RNA) viruses that have a
naked capsid structure. The family has more than 230
members divided into nine genera, including Enterovirus,
Rhinovirus, Hepatovirus (hepatitis A virus; discussed in
Chapter 55), Cardiovirus, and Aphthovirus. The enterovi-
ruses are distinguished from the rhinoviruses by the stabil-
ity of the capsid at pH 3, the optimum temperature
for growth, the mode of transmission, and their diseases
The Epstein–Barr virus (EBV), also called human herpesvirus 4 (HHV-4), is one of eight known human herpesvirus types in the herpes family, and is one of the most common viruses in humans.
herpes simplex virus is a double stranded DNA virus causing many symptoms all over the body. it affects globally all over the world .
neonatal hsv attacks even the baby and made them to a fatal conditions.
The Paramyxoviridae is a family of single-stranded RNA viruses known to cause different types of infections in vertebrates. Examples of these infections in humans include the measles virus, mumps virus, parainfluenza virus, and respiratory syncytial virus (RSV).
Polio: flaccid paralysis, major and minor
disease, fecal-oral
Coxsackievirus A: vesicular diseases,
meningitis; coxsackievirus B (body):
pleurodynia, myocarditis
Other echovirus and enteroviruses: like
coxsackievirus
Rhinoviruses: common cold, acid labile, does
not replicate above 33° C
Biology, Virulence, and Disease
• Small size, icosahedral capsid, positive RNA
genome with terminal protein
• Genome is sufficient for infection
• Encodes RNA-dependent RNA polymerase,
replicates in cytoplasm
Enteroviruses
• Capsid virus resistant to inactivation
• Disease due to lytic infection of important
target tissue
• Polio: cytolytic infection of motor neurons of
anterior horn and brainstem, paralysis
• Coxsackievirus A: herpangina, hand-foot-
and-mouth disease, common cold,
meningitis
• Coxsackievirus B: pleurodynia, neonatal
myocarditis, type 1 diabetes
Rhinoviruses
• Acid labile and cannot replicate at body
temperature
• Restricted to upper respiratory tract
• Common cold
Epidemiology
• Enteroviruses transmitted by fecal-oral route
and aerosols
• Rhinoviruses transmitted by aerosols and
contact
Diagnosis
• Immune assays (ELISA) or RT-PCR genome
analysis of blood, CSF, or other relevant
sample
Treatment, Prevention, and Control
• OPV and IPV polio vaccines
P
icornaviridae is one of the largest families of viruses and
includes some of the most important human and animal
viruses (Box 46-1). As the name indicates, these viruses are
small (pico) ribonucleic acid (RNA) viruses that have a
naked capsid structure. The family has more than 230
members divided into nine genera, including Enterovirus,
Rhinovirus, Hepatovirus (hepatitis A virus; discussed in
Chapter 55), Cardiovirus, and Aphthovirus. The enterovi-
ruses are distinguished from the rhinoviruses by the stabil-
ity of the capsid at pH 3, the optimum temperature
for growth, the mode of transmission, and their diseases
It might be thought that viruses as a class represent the ultimate in parasitism.
Reliant as they are on their host cells to provide most of the machinery or replication.
The Parvoviruses, show a still further degree of dependence .
The lecture gives concise review about the main four groups of viruses causing hemorrhagic fever i.e. Flavivirues, Filoviruses, Arenaviruses and Bunyaviruses.
A picornavirus is a virus belonging to the family Picornaviridae, a family of viruses in the order Picornavirales. Vertebrates, including humans, serve as natural hosts. Picornaviruses are nonenveloped viruses that represent a large family of small, cytoplasmic, plus-strand RNA viruses with a 30-nm icosahedral capsid.
It might be thought that viruses as a class represent the ultimate in parasitism.
Reliant as they are on their host cells to provide most of the machinery or replication.
The Parvoviruses, show a still further degree of dependence .
The lecture gives concise review about the main four groups of viruses causing hemorrhagic fever i.e. Flavivirues, Filoviruses, Arenaviruses and Bunyaviruses.
A picornavirus is a virus belonging to the family Picornaviridae, a family of viruses in the order Picornavirales. Vertebrates, including humans, serve as natural hosts. Picornaviruses are nonenveloped viruses that represent a large family of small, cytoplasmic, plus-strand RNA viruses with a 30-nm icosahedral capsid.
describes the etiopathogenesis , clinical features, investigations, differential diagnosis and management and prophylaxis of all important viral lesions affecting the oral cavity
A type of virus that causes herpes infections and has DNA as its genetic material. There are two types of human herpesviruses. Infections with type 1 viruses cause cold sores on the lips or nostrils. Infections with type 2 viruses cause sores on the genitals (external and internal sex organs and glands).
Infectious mononucleosis Made Extremely Simple!!! DrYusraShabbir
A brief description of a very common illness causing fever, rash and sore throat. Blood profile is altered. Commonly seen in adults as well as young children. Extremely useful for doctors, medical students, MD, dermatologists, pediatricians and Nurses.
Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Ve...kevinkariuki227
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
1. HERPES VIRIDAE Prevalent as early as ancient Greek times. Hippocrates described the cutaneous spreading of lesions. Shakespeare is thought to have been familiar with these lesions and their transmission and mentioned in his Romeo and Juliet . In 1893 Vidal recognized the human transmission of HSV infection from one individual to another. In 1919, Lowenstein confirmed experimentally the infectious nature of HSV. In 1920's and 1930's, the natural history and range of infections of HSV were studied. By the 1940's and 1950's, research established on diseases caused by HSV .
2. The members of this family are also known as herpesviruses . Name is derived from the Greek word herpein ("to creep or crawl"). Latent, reactivation , recurring and lytic infections are typical of this group of viruses. Herpesviridae , a large family of DNA viruses that cause diseases in animals and humans.
3.
4.
5.
6.
7.
8. 2 .Growth on Chick embryo CAM Shiny, non necrotic pocks.
9. Pathogenesis Enters ‘thru’ defects in skin &mucus membranes. Local multiplication Local LN involvement. Retrograde axonal flow from sensory nerves …. Reaches Ganglia. Maintains latency Viral replication in the nerves. Decreased CMI. Centrifugal migration to skin & mucus membranes. Recurrence of the disease. Physical, Emotional stress. Trauma, Fever. Sun light. Trigeminal, Sacral
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11.
12.
13. . Herpetic lesions in oral cavity Dental anomalies followed by Herpes viral infections.
14.
15. Eczema herpeticum Severe form of Atopic eczema (Kaposi's varicelliform eruption.) Extensive ulceration. Eye infections: Branching/dendritic corneal ulcer.
16.
17. -Symptomatic infections with sores, fever and lymphadenopathy of genital tract , heal within 2-4 weeks. -Patients may suffer with 4-5 outbreaks (recurrent) within a year. -Causes psychological distress. -Infection during late pregnancy poses a greater risk of transmission to the baby. - Sacral radiculopathy common with urinary retention. HSV- 2 transmitted by auto infection, sexual /orogenital contact. Most infections are asymptomatic.
18. Genital herpes Shaft of the Penis Labial herpes Perianal herpes
19. 2.Neonatal herpes Localized to Skin , eyes, mouth. Disseminated infection leads to Multi organ involvement (Liver, Adrenals, Brain) Complication: Neurological impairment. 3.Aseptic meningitis:
20.
21. 3.Antigen detection : Fluorescent antibody , ELISA 4.Viral isolation: Cell line culture – growth within 1 -3 days. 5.Molecular techniques: PCR and DNA probes. Treatment : No cure. Acyclovir : Primary infection (< 72 hrs). Reduce the recurrences. Famciclovir: For resistant cases.
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23.
24. Lab. Diagnosis : Same as HSV. Specimens : Buccal / Cutaneous lesions Prophylaxis : V – Z immunoglobulins. Live attenuated varicella vaccine.
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28.
29.
30. IMN like disease: Young adults. Hepatitis, fever, atypical lymphocytosis. (No pharyngitis, no lymphadenopathy, Negative for heterophile antibody) Respiratory tract infections: Pneumonitis in infants. Immunocompromised individuals: Pneumonia Fatal encephalitis Chorioretinitis
32. 2.Isolation: “ Human diploid fibroblast cell” culture. Large retractile cells with cytoplasmic granules. 3.Serology: Anti CMV IgM Ab estimation by ELISA. Treatment: Ganciclovir & Foscarnet. Prophylaxis: Acyclovir.
33.
34. Pathogenesis Infected saliva. Pharyngeal epithelial cells (Multiplies locally). Persistence Shed in saliva Invades blood stream Infects B. lymphocytes . Liver Spleen Polyclonal activation cell death . Unchecked replication results in Lymphomas Neoantigen formation Atypical lymphocytosis .
35.
36. 2.Chronic fatigue syndrome. 3.Malignancies associated with EB. Burkitt’s lymphoma (Malignant B cell lymphoma of jaw) Nasopharyngeal carcinoma Lymphomas in HIV infected persons.
37. Lab diagnosis 1.Blood smear examination : Atypical Lymphocytosis. 2.Paul - Bunnel test: Heterophile antibody detection test. Inactivated serum + 1% sheep RBC suspension 37 0 C 4 hrs Agglutination (>100) 3. EBV Specific antibodies: EBNA Ab EBNA Ig M VCA, Ig G VCA 4. PCR: More sensitive.
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40. Alzheimer's disease atherosclerosis cholangiocarcinoma Crohn's disease chronic fatigue syndrome fibromyalgia Irritable bowel syndrome multiple sclerosis pancreatic cancer pityriasis rosea Type II Diabetes Research is currently ongoing into a variety of side-effect or co-conditions related to the herpesviruses.
41. Prepared for e -learning by Dr .P.SRINIVASULU REDDY , M D., Professor, Department of Microbiology Narayana Medical College NELLORE
