To know what is Microbiology.
How much important of microbiology knowledge in our life.
Why need to know about Microbiology .
What type of diseases can occur in our body.
What is the role of Pharmaceutical Microbiology.
How can we prevent from the diseases.
Introduction to Microbiology , Microbes are every where , understand them so you can live with them . I hope you like this presentation my colleagues . it is useful to students and Infection control practitioners . ! Enjoy
Virus, infectious agent of small size and simple composition that can multiply only in living cells of animals, plants, or bacteria. The name is from a Latin word meaning “slimy liquid” or “poison.”
Contributions of Various scientist for the development of Microbiology field.
1. Antony Van Leeuwenhoek
2. Edwerd Jenner
3. Louis Pasteur
4. Joseph Lister
5. Robert Koch
6. Paul Ehrlich
7. Alexander Fleming
To know what is Microbiology.
How much important of microbiology knowledge in our life.
Why need to know about Microbiology .
What type of diseases can occur in our body.
What is the role of Pharmaceutical Microbiology.
How can we prevent from the diseases.
Introduction to Microbiology , Microbes are every where , understand them so you can live with them . I hope you like this presentation my colleagues . it is useful to students and Infection control practitioners . ! Enjoy
Virus, infectious agent of small size and simple composition that can multiply only in living cells of animals, plants, or bacteria. The name is from a Latin word meaning “slimy liquid” or “poison.”
Contributions of Various scientist for the development of Microbiology field.
1. Antony Van Leeuwenhoek
2. Edwerd Jenner
3. Louis Pasteur
4. Joseph Lister
5. Robert Koch
6. Paul Ehrlich
7. Alexander Fleming
Control of microorganism ppt
physical method Control of microbes
chemical method Control of microbes
types of Control of microbes
pasteurization Control of microbes
sterilization
disinfection
sanitization
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
The increased availability of biomedical data, particularly in the public domain, offers the opportunity to better understand human health and to develop effective therapeutics for a wide range of unmet medical needs. However, data scientists remain stymied by the fact that data remain hard to find and to productively reuse because data and their metadata i) are wholly inaccessible, ii) are in non-standard or incompatible representations, iii) do not conform to community standards, and iv) have unclear or highly restricted terms and conditions that preclude legitimate reuse. These limitations require a rethink on data can be made machine and AI-ready - the key motivation behind the FAIR Guiding Principles. Concurrently, while recent efforts have explored the use of deep learning to fuse disparate data into predictive models for a wide range of biomedical applications, these models often fail even when the correct answer is already known, and fail to explain individual predictions in terms that data scientists can appreciate. These limitations suggest that new methods to produce practical artificial intelligence are still needed.
In this talk, I will discuss our work in (1) building an integrative knowledge infrastructure to prepare FAIR and "AI-ready" data and services along with (2) neurosymbolic AI methods to improve the quality of predictions and to generate plausible explanations. Attention is given to standards, platforms, and methods to wrangle knowledge into simple, but effective semantic and latent representations, and to make these available into standards-compliant and discoverable interfaces that can be used in model building, validation, and explanation. Our work, and those of others in the field, creates a baseline for building trustworthy and easy to deploy AI models in biomedicine.
Bio
Dr. Michel Dumontier is the Distinguished Professor of Data Science at Maastricht University, founder and executive director of the Institute of Data Science, and co-founder of the FAIR (Findable, Accessible, Interoperable and Reusable) data principles. His research explores socio-technological approaches for responsible discovery science, which includes collaborative multi-modal knowledge graphs, privacy-preserving distributed data mining, and AI methods for drug discovery and personalized medicine. His work is supported through the Dutch National Research Agenda, the Netherlands Organisation for Scientific Research, Horizon Europe, the European Open Science Cloud, the US National Institutes of Health, and a Marie-Curie Innovative Training Network. He is the editor-in-chief for the journal Data Science and is internationally recognized for his contributions in bioinformatics, biomedical informatics, and semantic technologies including ontologies and linked data.
2. 2
• Sterilization: Removal of all microbial life.
• Commercial Sterilization: Food in cans is subjected to enough heat for a
complete sterility, for destroying Clostridium botulinum endospores, which
can produce a deadly toxin in food.
• Disinfection: Removal of pathogens (chemical, ultraviolet radiation, boiling
water, or steam).
• Antisepsis: Removal of pathogens on living tissue (use chemical
disinfectant).
• Degerming: Removal of microbes from a limited area, such as alcohol use
for the skin around an injection site or before receiving an injection.
• Sanitization: Lower microbial counts on eating utensils. May be done with
high temperature washing or by dipping into a chemical disinfectants.
Terminology
3. 3
• Treatment that cause outright death of microbes have suffix -cide,
meaning kill.
– Biocide/Germicide: Kills microorganisms (exception endospores)
– Fungicide: kills fungi
– Virucide: inactivates virus.
• Treatments only inhibit the growth or multiplication of bacteria have
suffix –stat or stasis.
– Bacteriostasis: Inhibiting, not killing, microbes.
• Sepsis: refers to microbial contamination as in a septic tanks for
sewage treatment. (toxic conditions resulting from the growth and
spread of bacteria in blood and tissue.
• Asepsis: is the absence of significant contamination.
• Aseptic: an object or area is free of pathogens.
– Aseptic technique is important in surgery techniques to prevent
microbial contamination of wounds.
4. 4
The rate of microbial death
Bacterial populations die at a constant logarithmic rate when heated
or when treated with antimicrobial chemicals.
Example: suppose a
population of 1 million
microbes has been
treated for 1 min,
and 90 % of the
population has died;
the population now is
100,000 microbes.
If the population is
treated for another
min, 90% of those
microbes 100,000
will die, so we left
with 10,000 microbes
alive, etc…1
5. 5
• Number of microbes
• Environment influence:
– The presence of organic matter often inhibits
the action of chemical antimicrobials. In
hospital, the presence of organic matter in blood
vomit, or feces influence the selection of
disinfectants.
– The nature of suspending medium is also a
factor in heat treatment. Fats and proteins are
especially protected, and a medium rich in these
substances protects microbes which will then
have a higher survival rate.
• Heat is more effective under acidic conditions.
• Time of exposure
• Microbial characteristics
Effectiveness of antimicrobial treatment depends on:
The effect of high or low initial
load of microbes. If the rate of
killing is the same, it will take
longer to kill all members of
larger population than a smaller
one. This is true for both heat
and chemical treatments.
6. 6
We examine the ways various agents actually kill or inhibit
microbes (the effects of microbial control agents on cellular
structure).
• Alternation of membrane permeability
– Damage to the lipids or proteins of the plasma membrane by
antimicrobial agents causes cellular content to leak into the
surrounding medium and interferes with growth of the cell.
• Damage to proteins
– Denaturation of protein
• Damage to nucleic acids
Actions of Microbial Control Agents
7. 7
When selecting methods of microbial control, consideration must be
given to effects on things besides the microbes.
Heat
Heat appears to kill microorganisms by denaturing their enzymes.
Heat resistance varies among different microbes;
• These differences can be expressed through the concept of thermal
death point.
– Thermal death point (TDP): the temperature required to kill all the bacteria
in liquid culture in 10 min.
• Another factor to be considered in sterilization is the length of time
required.
– Thermal death time (TDT): the length of time required to kill all the bacteria
in liquid culture at a given temperature.
• A third concept related to bacterial heat resistant is the Decimal
reduction time (DRT): The time (in minutes) required to kill 90% of a
bacterial population at a given temperature; also called D value.
Physical Methods of Microbial Control
8. 8
• Moist heat: killing microorganisms by the coagulation of proteins
(denaturation), which is caused by breakage of the hydrogen bonds that
holds the proteins in three dimensional structure (example: egg white
frying).
– One type of moist heat sterilization is boiling, which kills vegetative form of
bacterial pathogens.
– Reliable sterilization with moist heat requires temperature above boiling water.
• It can be achieved by steam under pressure in an autoclave. The higher the
pressure the higher temperature.
Pressure 15 psi 121ºC
Pressure 20 psi 126ºC
psi: pressure per square inch
9. 9
• Pasteurization reduces spoilage organisms (lowering microbial number) and
pathogens
• In the classic pasteurization treatment of milk, the milk was exposed to a
temperature (to eliminate pathogenic microbes, and to lower the microbial
numbers, which prolongs milk’s good quality under refrigeration) of about:
– 63°C for 30 min
– High-temperature short-time (HTST) 72°C for 15 sec
• Milk also can be sterilized by something quite different from
pasteurization by Ultra-high-temperature (UHT) so that it can be stored
without refrigerator: 140°C for <1 sec
• The concept of equivalent treatments: Different methods that have the
same effect on controlling microbial growth.
• Many relatively heat resistant (thermoduric) organisms survive
pasteurization, but these are unlike to cause disease or cause refrigerated
milk to spoil.
Pasteurization
10. 10
• One of the simplest method of Dry Heat Sterilization:
– Flaming
– Incineration (an effective way to sterilize and dispose of contaminated
cups, bags, dressing)
– Hot-air sterilization (temperature of about 170ºC maintained for nearly
2 hours ensures sterilization.
Dry Heat Sterilization
Hot-air Autoclave
Equivalent treatments 170˚C, 2 hr 121˚C, 15 min
• Filtration
– removes microbes
• Low temperature
– inhibits microbial growth
Refrigeration Deep freezing Lyophilization
• High pressure
– denatures proteins
11. 11
• Desiccation
– In the absence of water, microorganisms cannot grow or
reproduce but remain viable for years. Then when water is made
available to them, they can resume their growth and division.
– For example: The gonorrhea bacterium can withstand dryness
for only about an hour, while the tuberculosis bacterium can
remain viable for months. Viruses are normally resistant to
desiccation, but they are not resistant as bacterial endospores,
some of which survive for centuries.
• Osmotic pressure:
– The use of high concentrations of salts and sugars to preserve
food.
– causes plasmolysis
12. 12
Radiation
• Damages DNA
• Radiation has various effects on cells, depending on its wavelength, intensity,
and duration. Radiation that kills microorganisms (sterilizing radiation) is of
two types: ionizing and nonionizing.
– Ionizing radiation: (X rays, gamma rays or high energy electron beams),
have a wavelength shorter than nonionizing radiation, less than about 1nm.
– Nonionizing radiation: (UV) has a wavelength longer than that of ionizing
radiation, ususlalay greater than about 1nm.
– Microwaves: microorganism can be killed by heat; not especially
antimicrobial (do not have much direct effect on microorganism)