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.
Introduction
History
Types of immunity
Tissues of immunity
Cells of immunity
Basic aspects of immunology
Major histocompatibility complex
Cytokines
Disorders of immune system
Immune responses in periodontal pathogenesis
Periodontal vaccine
Host modulation
Conclusion
References
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).
Mycobacterium is a genus of Actinobacteria, given its own family, the Mycobacteriaceae. Over 190 species are recognized in this genus. This genus includes pathogens known to cause serious diseases in mammals, including tuberculosis (Mycobacterium tuberculosis) and leprosy (Mycobacterium leprae) in humans.
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.
Introduction
History
Types of immunity
Tissues of immunity
Cells of immunity
Basic aspects of immunology
Major histocompatibility complex
Cytokines
Disorders of immune system
Immune responses in periodontal pathogenesis
Periodontal vaccine
Host modulation
Conclusion
References
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).
Mycobacterium is a genus of Actinobacteria, given its own family, the Mycobacteriaceae. Over 190 species are recognized in this genus. This genus includes pathogens known to cause serious diseases in mammals, including tuberculosis (Mycobacterium tuberculosis) and leprosy (Mycobacterium leprae) in humans.
Viruses that infect and parsitized bacteria is known as bacteriophage.
It was discovered by Frederick.W.Twort in Great Britian (1915) and Felix d’ Herelle in France(1917).
D’ Herelle coined the term bacteriophage meaning ‘bacterial eater’ to describe the agent’s bacteriocidal activity. He observed lysis of a broth culture of a dysentry bacillus.
This presentation contains 53 power point slides. These slides have description between virus and host cell interactions including concept of permissive and non-permissive infection, latent infection and host immune response to viral infection. Slides are designed for medical students, nurses, academicians who are teaching virology and microbiology in medical universities, schools or college.
This presentation contains 45 slides on general virology comprises of topics on viral classification, transmission, pathogenesis, viral cytopathic effect, stages of viral infections, antiviral drugs and viral vaccines. It also have a slide noting an outline of laboratory diagnosis of viral infection. This power point presentation was designed for medical students, nurses and academicians teaching virology and microbiology in medical universities, schools or colleges.
Viruses that infect and parsitized bacteria is known as bacteriophage.
It was discovered by Frederick.W.Twort in Great Britian (1915) and Felix d’ Herelle in France(1917).
D’ Herelle coined the term bacteriophage meaning ‘bacterial eater’ to describe the agent’s bacteriocidal activity. He observed lysis of a broth culture of a dysentry bacillus.
This presentation contains 53 power point slides. These slides have description between virus and host cell interactions including concept of permissive and non-permissive infection, latent infection and host immune response to viral infection. Slides are designed for medical students, nurses, academicians who are teaching virology and microbiology in medical universities, schools or college.
This presentation contains 45 slides on general virology comprises of topics on viral classification, transmission, pathogenesis, viral cytopathic effect, stages of viral infections, antiviral drugs and viral vaccines. It also have a slide noting an outline of laboratory diagnosis of viral infection. This power point presentation was designed for medical students, nurses and academicians teaching virology and microbiology in medical universities, schools or colleges.
A virus is an obligate intracellular parasite containing genetic material surrounded by protein
Virus particles can only be observed by an electron microscope
Most viruses range in sizes from 20 – 250 nanometers
Introduction to virology for Medical studentsNCRIMS, Meerut
Introduction to virology for MBBS students
A virus is an obligate intracellular parasite containing genetic material surrounded by protein
Virus particles can only be observed by an electron microscope
Most viruses range in sizes from 20 – 250 nanometers
Viruses are obligate intracellular parasites
Viruses are non-living entities
Viruses cannot make energy or proteins independent of a host cell (Depends on host cell for replication)
Viral genome are either RNA or DNA but not both.
Viruses have a naked capsid or envelope with attached proteins
Do not possess cellular organization
Viruses do not have the genetic capability to multiply by division.
They are NOT cultiviable on ordinary media.
Much smaller than bacteria
“Filterable agents” – can pass through filters that can hold back bacteria
Vary widely in size:
Largest – poxvirus (300nm)
Smallest – parvovirus (20nm)
Immunofluorescence is a technique allowing
the visualization of a specific antigen by
bindIng a specific antibody chemically
conjugated with a fluorescent dye.
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.
Richard's aventures in two entangled wonderlandsRichard 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.
What is greenhouse gasses and how many gasses are there to affect the Earth.moosaasad1975
What are greenhouse gasses how they affect the earth and its environment what is the future of the environment and earth how the weather and the climate effects.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
Deep Behavioral Phenotyping in Systems Neuroscience for Functional Atlasing a...Ana Luísa Pinho
Functional Magnetic Resonance Imaging (fMRI) provides means to characterize brain activations in response to behavior. However, cognitive neuroscience has been limited to group-level effects referring to the performance of specific tasks. To obtain the functional profile of elementary cognitive mechanisms, the combination of brain responses to many tasks is required. Yet, to date, both structural atlases and parcellation-based activations do not fully account for cognitive function and still present several limitations. Further, they do not adapt overall to individual characteristics. In this talk, I will give an account of deep-behavioral phenotyping strategies, namely data-driven methods in large task-fMRI datasets, to optimize functional brain-data collection and improve inference of effects-of-interest related to mental processes. Key to this approach is the employment of fast multi-functional paradigms rich on features that can be well parametrized and, consequently, facilitate the creation of psycho-physiological constructs to be modelled with imaging data. Particular emphasis will be given to music stimuli when studying high-order cognitive mechanisms, due to their ecological nature and quality to enable complex behavior compounded by discrete entities. I will also discuss how deep-behavioral phenotyping and individualized models applied to neuroimaging data can better account for the subject-specific organization of domain-general cognitive systems in the human brain. Finally, the accumulation of functional brain signatures brings the possibility to clarify relationships among tasks and create a univocal link between brain systems and mental functions through: (1) the development of ontologies proposing an organization of cognitive processes; and (2) brain-network taxonomies describing functional specialization. To this end, tools to improve commensurability in cognitive science are necessary, such as public repositories, ontology-based platforms and automated meta-analysis tools. I will thus discuss some brain-atlasing resources currently under development, and their applicability in cognitive as well as clinical neuroscience.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
This presentation explores a brief idea about the structural and functional attributes of nucleotides, the structure and function of genetic materials along with the impact of UV rays and pH upon them.
2. CONTENTS
A. Rhabdovirus
• Introduction
• Classification
• Morphology
• Antigenic properties and host range
• Life cycle
B. Rabies virus
• Introduction
• Classification
• Epidemiology
• Pathogenesis
• Symptoms
• Clinical diagnosis
• Treatment
• Prevention
• Next generation vaccine
• References
07-08-2021 2
3. Introduction
• The term Rhabdovirus is derived from Greek word “rhabdos” meaning rod,
but virus have a bullet shape or bacilliform morphology.
• The family Rhabdoviridae consists of more than 100 viruses that infect a wide
variety of hosts including a vertebrate ,invertebrate and plants.
• It has been suggested that some rhabdovirus that infect plant may also infect
vertebrates.
• More over, one member Vesicular stomatitis virus infects several vertebrates
hosts, multiplies in Aedes mosquitoes and grow in leafhoppers , which are the
natural vector of maize mosaic virus, a plant rhabdovirus.
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4. Classification
• According to the ICTV report 2019 on virus classification
and taxon nomenclature the family rhabdoviridae
contains 30 genera and 191 species.
• The family rhabdoviridae fall into 4 groups based on the
RNA polymerase gene.
• The basal clade appears to be Novirhabdoviruses, which
infect fish.
• Cytorhabdoviruses and the Nucleorhabdoviruses, which
infect plants, are sister clades.
• Lyssaviruses which infect vertebrates and insects.
• Rhabdovirus that infects specifically mammals are
grouped in 2 genera :-
1. Vesiculovirus
2. Lyssavirus
Realm: Riboviria
Kingdom: Orthornavirae
Phylum: Negarnaviricota
Class: Monjiviricetes
Order: Mononegavirales
Family: Rhabdoviridae
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5. Morphology
• Common to all members of the family rhabdoviridae is a distinctive rod or bullet shape of
morphology.
• 180 x 75 nm in size with one end rounded or conical & the other end planar or concave.
• All rhabdoviruses have two major structural components: a helical ribonucleoprotein core (RNP)
and a surrounding envelope.
• The genome of rhabdovirus is single stranded ,non-segmented , negative sense RNA(-) molecule
that makes up about 2% of the virus particle.
• Most of the rhabdovirus contains five proteins :-
• 1. glycoprotein (G)- surface antigen.
• 2. matrix protein (M)- keep nucleoprotein condensed , important for assembly.
• 3. large protein (L)- RNA dependent RNA polymerase.
• 4. Non structural protein (NS)- phosphoprotein, L cofactor and various regulatory functions.
• 5. nucleoprotein (N)- RNA binding protein (coats the RNA).
• Virion also contains a lipid bilayer as a envelope which are derived entirely from the host cell.
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7. Antigenic properties and host range
• The glycoprotein is the major antigenic determinant responsible for type
specificity and give rise to neutralizing the antibody.
• The Glycoprotein spike is responsible for attachment with host ,removal of
which by protease reduces infectivity more than 105 fold.
• The concept is that the terminal sialic acid in the carbohydrate chains of
virion is responsible for efficient infectivity and adsorption to host cells.
• The lipid bilayer also play some role in its infectivity .Exposure to
phospholipase reduces infectivity.
• It is suggested that phosphatidyl serine and phosphatidyl choline are receptor
site for rhabdovirus.
• Acetylcholine receptor on neural tissue have been postulated to be receptor
sites for attachment of rabies virus on the basis of reduced infectivity after
exposure to 𝛼- bungarotoxin and 𝛼- tubocurarine.
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8. • Rabies virus has hemolysis activity, optimally seen at 0 - 40C & pH 5.
• It is inactivated by heat 560C for 30 – 60 min or exposure of ether ,trypsin.
Rhabdovirus infect a wide variety of hosts
including a vertebrate ,invertebrate and plants.
ANIMALS –
All mammals are susceptible to Rhabdovirus.
Cattle, cats ,bats & foxes – Highly susceptible.
Skunks, opossums & fowl – relatively resistant.
Humans & dogs occupy an intermediate position.
Pups are more susceptible than adults.
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9. Life cycle
• When an infectious virion of the family Rhabdoviridae
encounters a susceptible host cell, the result is often a
series of events that terminates in release of progeny
virions and, frequently, death of the cell.
• Adsorption - attachment of virion to host cell by its
receptor that is glycoprotein spike.
• Penetration- fusion of virus with host cell surface
thereafter discharging the virus containing coated
vesicle into the cytoplasm.
• Uncoating – after endocytosis , the coated vesicle
fused with lysosome , thus resulting in release of
nucleocapsid.
• Transcription – this is the first metabolic event after
penetration and uncoating of rhabdovirus.
• N protein encapsulated RNA genome acts as a template
and L & NS proteins are required for transcription
initiation.
07-08-2021 9
10. • Translation - Translation of each of the mRNAs of
virion, proceeds immediately after, and in fact is
coupled with transcription.
• The glycoprotein is synthesized on endoplasmic
reticulum membrane associated polyribosomes by
means of signal sequence , step wise glycosylation.
• The other 4 protein are synthesized from
monocistronic m-RNA on cytoplasmic polyribosomes.
• Replication – virus contain ssRNA genome with a
negative polarity, meaning that their sequence is
complementary to the m-RNA.
• Full length of positive RNA strands are made to serve as
a template for the production of the negative strand.
• Assembly – the final assembly of virus from its
components takes place at plasma membrane of
infected host cells. viral nucleocapsid (N)protein is first
synthesized then assembles with RNA to form the
nucleocapsid and then remaining proteins are
assembled.
• Budding – budding of virions from the apical or
basolateral region of host cell membrane has been
extensively studied.
10
12. Introduction
• Rabies lyssavirus, formerly Rabies virus
(RABV), is a neurotropic virus that causes
rabies in humans and animals.
• Rabies virus transmission can occur through
the saliva of infected animals and less
commonly through contact with human
saliva.
• Like many rhabdoviruses, Rabies lyssavirus
has an extremely wide host range.
• Generally it infect many mammalian species ,
while in the laboratory condition it has been
found that birds can be infected ,as well as
cell culture from mammals , birds, reptiles
and insects.
07-08-2021 12
Realm: Riboviria
Kingdom: Orthornavirae
Phylum: Negarnaviricota
Class: Monjiviricetes
Order: Mononegavirales
Family: Rhabdoviridae
Genus Lyssavirus
Species rabies lyssa virus
Classification
13. Epidemiology and burden of rabies
• Rabies is estimated to cause 59,000 human deaths annually in over 150 countries, with 95%
of cases occurring in Africa and Asia.
• Rabies is a major burden in Asia, with an estimated 35,172 human deaths per year.
• India accounts for 59.9% of rabies deaths in Asia and 35% of deaths globally. The cost of Post
Exposure Prophylaxis (PEP) is highest in Asia, with estimates up to US$ 1.5 billion per year.
07-08-2021 13
15. Symptoms
Non specific symptoms
• Pruritus
• Paresthesia
• Pain
• Fever
• Malaise
• Irritability
• Headache
• Nausea
• Vomiting
• Agitation
• depression
07-08-2021 15
Paralytic symptoms
• Local muscle weakness
• Facial weakness
Encephalitic symptoms
• Confusion
• Hallucination
• Hypersalivation
• Hydrophobia
• Aerophobia
• Late complications (
cardiac failure ,
respiratory failure , multi
organ failure )
• coma
16. Clinical diagnosis
• Specimen – corneal smear ,skin biopsy (from neck and face),saliva ,brain(CSF).
• Types of diagnosis :-
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1.Rabies antigen detection
2. Viral detection
3.Antibody detection
4. Viral RNA detection
5. Negri body detection
1.Rabies antigen detection – from corneal smear by direct immunofluorescence
test. Direct immunofluorescence is done by using monoclonal antibodies tagged with
fluorescein isothiocyanate.
2.Viral isolation by –
Animal inoculation -Isolation of virus by intracerebral inoculation in mice attempted
from brain, CSF, saliva & urine .
17. • Cell lines inoculation -Isolation of virus in tissue culture cell lines . Mouse neuroblastoma ,[BHK]baby
hamster kidney cell lines are used .Identified by immunofluorescence.
3.Antibody detection – from CSF (imp.) and serum(late appearance).
• MNT – mouse neutralization test.
• RFF-IT- rapid fluorescence focus inhibition test.
• FAVN- fluorescent antibody neutralization virus test.
• IFA- indirect fluorescence assay.
• HAI- hemagglutination inhibition test.
• CFT- complement fixation test.
4.Viral RNA detection- Detection of rabies virus RNA by reverse transcriptase PCR is a sensitive and
specific molecular method.
5. Negri body detection – Negri body is eosinophilic inclusion but it has basophilic inner granules .Negri
body detection is accomplished by histopathological staining of brain biopsy(cerebral tissue).
H and E stain ,Seller’s stain are used .
Immunohistochemistry- peroxidase labelled specific antibodies are used to Negri body detection in
formalin fixed tissue. It is more sensitive and specific than staining methods.
07-08-2021 17
18. Treatment
• Post exposure treatment consists of :-
1.Local treatment of wound –
Wash wound immediately with soap and water preferably for 10 minutes.
Chemical treatment – alcohol tincture iodine ,any antiseptic.
Anti tetanus prophylaxis.
Antimicrobial –Amoxicillin , cloxacillin , cefuroxime.
07-08-2021 18
1.Local treatment of the wound
2. Administration of rabies immunoglobulin (passive immunization).
3. Immediate vaccination (active immunization).
19. 2.Administration of rabies immunoglobulin –
HRIG- Human Rabies immunoglobulin , horse anti rabies serum are used for passive immunization.
Booster doses are essential whenever anti rabies serum is given.
3.Immediate vaccination –
Vaccine is a fluid or dried preparation of Rabies “fixed” virus grown in the neural tissue of rabid animal such
as sheep, rabbit etc. or in embryonated duck egg or in cell culture .
A. Neural vaccine-
It contains 5% suspension of infected sheep brain (infected with fixed virus) .inactivated with phenol at 37 °C.
Vaccine available after inactivation with beta propiolactone.
B. Egg vaccine-
➢Duck egg vaccine – prepared from a fixed virus inactivated by beta propiolactone.
➢Live attenuated chick embryo vaccine.
C. Tissue culture vaccine –
➢Human diploid cell vaccine [HDCV].
➢Purified chick embryo cell vaccine [PCEC].
➢Purified Vero cell vaccine [PVRV].
➢Purified duck embryo vaccine [PDEV].
07-08-2021 19
20. Vaccine doses -
❖Intramuscular regimen [0-3-7-14-28]
➢1 ml doses given intramuscular deltoid (children - anterolateral aspect of thigh ).
➢Five doses of vaccine should be given on day 0 , 3 , 7 , 14 , 28.
❖Intra Dermal Schedule (0-3-7-28- 90)
➢Two site Intra Dermal Vaccination has been used in India , endorsed by WHO Expert Committee on
rabies.
➢0.2ml doses given at each two sites on day 0 , 3 , 7 & one site on days 28 , 90.
➢ Intradermal dose is 1/5th of intramuscular dose.
07-08-2021 20
21. Prevention
➢ Eliminating rabies in dogs and other pets-
eliminating rabies in dogs through vaccination. This has reduced the number of human rabies cases
prevention of human rabies through control of domestic dog rabies is a realistic goal.
➢Preventive immunization in people-
Pre-exposure immunization in people who have a high risk of getting infected with rabies virus . these
persons include veterinarians, animal handler ,traveller who will spent more than 1 month in
countries having a high rate of rabies infection.
It should be given on following days – 0-7-21 or 28 and 56th day.
➢Epidemiological surveillance-
Dog bites must be notifiable within national surveillance system on weekly basis.
Collected data should be processed and disseminated rapidly between different administrative levels .
Dog movement.
Dog vaccination status.
07-08-2021 21
22. Next generation rabies vaccines
• A number of experimental vaccines are under development that
may provide alternative ,safe and potent but less expensive
vaccine options. These include, recombinant viral vaccines, DNA
based rabies vaccine and oral rabies vaccine derived from plants.
➢ Recombinant rabies virus vectored vaccine –
To generate a more stable variants of rabies viral vaccine variety of
foreign genes inserted into viral genome .
➢ DNA based rabies vaccine –
For developing new generation rabies vaccine is to use a DNA based
or plasmid vaccine encoding the rabies glycoprotein gene.
➢ Oral rabies vaccine derived from plant –
Plants has provided new system for the large scale production of
recombinant protein at low cast , simplifying the production
process.
A variety of genetically engineered vaccines using Tobacco mosaic
virus and Tomato bushy stunt virus have been developed for
expressing for antigen in plants.
07-08-2021 22
23. References -
• Wagner, Robert R. "Rhabdovirus biology and infection." The
Rhabdoviruses. Springer, Boston, MA, 1987. 9-74.
• http://80.82.78.35/get.php?md5=c30dd6e4625221d68cb4f038f1
90ef62&key=DG4GTFJ8K1B5GU92&mirr=1
• https://www.who.int/rabies/epidemiology/en/#:~:text=Rabies%
20is%20estimated%20to%20cause,the%20true%20burden%20o
f%20disease.
• https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3623496/
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