This document discusses viruses and methods for cultivating viruses. It describes viruses as obligate intracellular parasites that can only multiply inside living host cells. The three main methods for cultivating viruses discussed are inoculation of viruses into animals, embryonated eggs, and tissue culture. For animal inoculation, mice are commonly used and viruses can be introduced via different routes. Embryonated eggs provide a suitable environment for virus growth and isolation. Tissue culture involves culturing cells or tissue fragments, and cell lines provide indefinite growth. Detection of virus growth involves monitoring for cytopathic effects, hemadsorption, interference, and other methods.
Serological test for virus identificationPlock Ghosh
This presentation consist of detailed study of serological method of virus identification. Basically ELISA is vastly used for virus detection. Western blot method is used for HIV identification.
Serological test for virus identificationPlock Ghosh
This presentation consist of detailed study of serological method of virus identification. Basically ELISA is vastly used for virus detection. Western blot method is used for HIV identification.
Viruses are obligate intracellular parasites so they depend on host for their survival. They cannot be grown in non-living culture media or on agar plates alone, they must require living cells to support their replication.Cultivation of viruses can be discussed under following headings:
Animal Inoculation
Inoculation into embryonated egg
Cell Culture
Adenoviridae is a group of medium sized, non-enveloped, double stranded DNA viruses that replicate and produce disease in the eye and in the respiratory, gastrointestinal and urinary tracts;
Largest viruses that infect vertebrates
Can be seen under light microscope
Poxvirus diseases are characterized by skin lesions – localized or generalized
Important diseases caused by poxviruses are-
Smallpox
Monkeypox
Cowpox
Tanapox
Molluscum contagiosum
Poxviruses are brick or oval-shaped viruses with large double-stranded DNA genomes. Poxviruses exist throughout the world and cause disease in humans and many other types of animals. Poxvirus infections typically result in the formation of lesions, skin nodules, or disseminated rash.
Ouchterlony double immunodiffusion (also known as passive double immunodiffusion) is an immunological technique used in the detection, identification and quantification of antibodies and antigens, such as immunoglobulins and extractable nuclear antigens.
Viruses are obligate intracellular parasites so they depend on host for their survival. They cannot be grown in non-living culture media or on agar plates alone, they must require living cells to support their replication.Cultivation of viruses can be discussed under following headings:
Animal Inoculation
Inoculation into embryonated egg
Cell Culture
Adenoviridae is a group of medium sized, non-enveloped, double stranded DNA viruses that replicate and produce disease in the eye and in the respiratory, gastrointestinal and urinary tracts;
Largest viruses that infect vertebrates
Can be seen under light microscope
Poxvirus diseases are characterized by skin lesions – localized or generalized
Important diseases caused by poxviruses are-
Smallpox
Monkeypox
Cowpox
Tanapox
Molluscum contagiosum
Poxviruses are brick or oval-shaped viruses with large double-stranded DNA genomes. Poxviruses exist throughout the world and cause disease in humans and many other types of animals. Poxvirus infections typically result in the formation of lesions, skin nodules, or disseminated rash.
Ouchterlony double immunodiffusion (also known as passive double immunodiffusion) is an immunological technique used in the detection, identification and quantification of antibodies and antigens, such as immunoglobulins and extractable nuclear antigens.
Viruses are obligate intracellular parasites which means they can only grow or reproduce inside a host cell.
The primary purpose of virus cultivation:
To isolate and identify viruses in clinical samples.
To do research on the viral structure, replication, genetics, and effects on the host cell.
To prepare viruses for vaccine production.
Isolation of the virus is always considered a gold standard for establishing the viral origin of the disease
topics covered
CULTIVATION OF VIRUSES
Animal inoculation
Embryonated eggs
CAM
Allantoic cavity
Amniotic cavity
Yolk sac
Tissue culture
Organ culture
Explant culture
Cell culture
Primary cell culture
diploid cell culture
Continues cell lines
VIRAL VACCINES
Since viruses are intracellular parasites they will grow only within other living cells.
Methods of viral vaccine production:
Cultivation of virus using free living animals
Fertile eggs
Tissue cultures
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
In this webinar you will learn how your organization can access TechSoup's wide variety of product discount and donation programs. From hardware to software, we'll give you a tour of the tools available to help your nonprofit with productivity, collaboration, financial management, donor tracking, security, and more.
How to Split Bills in the Odoo 17 POS ModuleCeline George
Bills have a main role in point of sale procedure. It will help to track sales, handling payments and giving receipts to customers. Bill splitting also has an important role in POS. For example, If some friends come together for dinner and if they want to divide the bill then it is possible by POS bill splitting. This slide will show how to split bills in odoo 17 POS.
We all have good and bad thoughts from time to time and situation to situation. We are bombarded daily with spiraling thoughts(both negative and positive) creating all-consuming feel , making us difficult to manage with associated suffering. Good thoughts are like our Mob Signal (Positive thought) amidst noise(negative thought) in the atmosphere. Negative thoughts like noise outweigh positive thoughts. These thoughts often create unwanted confusion, trouble, stress and frustration in our mind as well as chaos in our physical world. Negative thoughts are also known as “distorted thinking”.
The Art Pastor's Guide to Sabbath | Steve ThomasonSteve Thomason
What is the purpose of the Sabbath Law in the Torah. It is interesting to compare how the context of the law shifts from Exodus to Deuteronomy. Who gets to rest, and why?
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
Chapter 3 - Islamic Banking Products and Services.pptx
Cultivation of viruses uhf copy - copy
1.
2. Presented to : Dr. Sunita Devi
Presented by : Heena Chandel
3. VIRUSES
Viruses are obligate intracellular
parasites.
They multiply only inside the living
host cells. Animals ,plants ,humans ,
bacteria, fungus ,protozoa and algae
are the natural hosts of viruses.
4. Viruses are host specific and grow only in
selective hosts. Virologists use only a suitable
host system for cultivation of a virus.
Viruses cannot grow in artificial media .They
cannot grown in non-living culture or on agar plates
alone , they must require living cells to support their
replication.
There is no universal cell that will support all
viruses.
5. Main purpose of virus cultivation
To isolate and identify viruses in
clinical samples.
To prepare viruses for vaccine
production.
To do research on viral structure
, replication , genetics and
effects on host cells.
6. Reed and colleagues (1900) used human
volunteers for their pioneering work on yellow fever . Due to
the serious risk involved , human volunteers are used only
when no other method is available and when virus is
relatively harmless.
Monkeys were used for the isolation of the poliovirus by
Landsteiner and Popper (1909). However, due to
their cost and risk to handlers, monkeys find only limited
applications in virology.
The use of white mice, pioneered by Theiler (1903)
extended the scope of animal inoculation greatly.
7. Good Pasture in 1931 first used the embryonated
hen’s egg for the cultivation of virus and this method is
further developed by Burnet.
The first application of tissue culture in virology was by
Steinhardt and colleagues (1913), who maintained
the vaccinia virus in fragments in rabbit cornea.
Maitland (1928) used chopped tissue in nutrient
media for cultivation of vaccinia viruses.
The turning point which made tissue culture the most
important method for cultivation of virus was the
demonstration by Enders, Weller and Robins (1949),
that poliovirus till then considered a strictly neurotropic
virus,could be grown in tissue culture of non-neural origin.
8. METHODS FOR CULTIVATION OF VIRUSES
Inoculation of virus
into animals.
Inoculation of virus
into embryonated eggs.
Tissue culture.
9. Viruses which are not cultivated in
embryonated egg and tissue culture are
cultivated in laboratory animals. e.g: mice,
guinea pig , hamester , rabbits and
primates are used.
The selected animals should be healthy
and free from any communicable diseases.
Suckling mice (less than 48 hours old) are
most commonly used.
1). Inoculation of Virus in
Animals
10. Different ways of inoculation in mice are:
1). Intracerebral.
2). Subcutaneous.
3). Intraperitoneal.
4). Intranasal.
11. 1). Intracerebral
It occurring within
or introduced or
administered into the
cerebrum. It means
when a diseased blood
vessel within the brain
bursts allowing blood
to leak inside the brain.
12. 2). Subcutaneous
A subcutaneous
injection is an
injection in which a
needle is inserted
just under the skin.
14. 4). Intranasal
It lying within or administered by way
of the nasal structure.
15. Advantages and disadvantages
of animal inoculation :
Advantages :
Production of antibodies can be identified.
Diagnosis , pathogenesis and clinical
symptoms are determined.
Primary isolation of certain viruses.
Mice provide a reliable model for
studying viral replication.
Used for the study of immune
responses,epidemology and oncogenesis.
16. Disadvantages :
Expensive and difficulties in
maintaince of animals.
Difficulty in choosing of animals for
particular virus.
Some human viruses cannot be
grown in animals or can be grown but
do not cause diseases.
Mice do not provide models for
vaccine development.
17. 2). Inoculation of virus into
embryonated egg
The process of cultivation of viruses in
embryonated eggs depend upon the
type of egg being used.
Egg provide a suitable means for :
i. The primary isolation and
identification of viruses.
ii. The production of vaccines.
iii. The maintaince of stock culture.
18. After incubation , the egg is broken and virus is
isolated from tissue of egg.
For inoculation , eggs are first prepared for cultivation ,
the sheel surface are first prepared for cultivation , the
shell surface is first disinfected with iodine and
penetrated with a small sterile drill.
Viruses are inoculated into chick embryo of 7-12
days old.
20. Virus growth and multiplication in
the egg embryo is indicated by the
death of the embryo , by embryo cell
damage , or by the formation of
typical pocks or lesions on the egg
membrane.
Viruses can be cultivated in
various pats of egg like :
1). Chorioallantoic membrane (CAM)
2). Allantoic cavity
3). Amniotic sac
4). Yolk sac Pock
21. 1). Chorioallantoic
membrane (CAM)
Inoculation is mainly for
growing poxvirus.
After incubation and visible
lesions called pocks are
observed , which is grey white
area in transparent CAM.
Herpes simplex virus is also
grown.
Single virus gives single pocks.
This method is suitable for
plaque studies.
22. Plaque : A clear area in a lawn of
host cells that results from the lysis of
host cells by viruses.
23. 2). Allantoic cavity:
Inoculation is mainly done for
production of vaccine of
influenza virus , yellow fever ,
rabies.
Most of avaian viruses can be
isolated using this method.
Allantoic inoculation is a quick
and easy method that yields
large amounts (8-15ml) of
virus-infected egg fluids.
24. 3). Amniotic sac :
Inoculation is mainly done
for primary isolation of
influenza virus and the
mumps virus.
Growth and replication of
virus in egg embryo can be
detected by
haemagglutination assay.
The virus is introduced
directly into the amniotic fluid
that bathes the developing
embryo.
25. 4). Yolk sac inoculation :
It is also a simplest
method for growth and
multiplication of virus.
It is inoculated for
cultivation of some
viruses and some
bacteria ( Chlamydia ,
Rickettsiae ).
Immune interference
mechanism can be
detected in most of avian
viruses.
26. Advantages of inoculation into
embryonated egg
Widely used method for the isolation of virus and
growth.
Cost effective and maintenance is much easier.
The embryonated eggs are readily available.
They are free from contaminating bacteria and
many latent viruses.
Ideal substrate for the viral growth and replication.
less labor is needed.
Widely used method to grow virus for some
vaccine production.
Defense mechanisms are not involved in
embryonated eggs.
27. Disadvantage of inoculation into
embryonated egg
• The site of inoculation for varies with
different virus . That is , each virus
have different sites for growth and
replication.
28. 3). Tissue culture
Cultivation of bits of tissues and organs in
vitro had been used by physiologists and
surgeons for the study of morphogenesis
and wound healing.
Before the advent of cell culture , animal viruses
could be propagated only on whole animals or
embryonated chicken eggs.
29. Cell cultures have replaced
embryonated eggs as preferred
type of growth medium for
many viruses.
Cell culture consists of cells
grown in culture media in the
laboratory.
30. There are three types of tissue culture:
1). Organ culture.
2). Explant culture.
3). Cell culture.
31.
32. 1). Organ culture
Example: Tracheal ring organ culture is employed for the isolation of
coronavirus, a respiratory pathogen.
Organ culture is useful for the isolation of some viruses which appear
to be highly specialized parasites of certain organs.
Small bits of organs can be maintained in vitro for days and weeks,
preserving their original architecture and function. Formalin is used for
the preservation.
33.
34. 2). Explant culture
Example : Adenoid tissue explant culture were used for the isolation of
adenoviruses.
Enough volume of medium is poured into the petri dish , which is then
incubated at 37 ⁰C untill cell growth.
An explant is aseptically transferred into a sterile petri dish by using a fine
tipped forceps and then a coverslip is placed over that explant.
The explants taken from laboratory animals such as mice , rabbit , guinea pigs
, hamester and man can be grown in petri dishes.
A small portion of tissue excised from animal’s body is explant.
36. 3). Cell culture
The essiential constitutents of the growth medium are physiologic amounts of
essiential amino acids and vitamins , salts , glucose and a buffering system
generally consisting of bicarbonate in equilibrium with atmosphere containing
about 5% carbon dioxide.
Tissues are dissociated into the components of cells by the
action of proteolytic enzymes such as trypsin and mechanical
shaking.
This is the type of culture routinely employed for growing
viruses.
37. The cell adhere to the glass surface and on incubation ,
divide to form a confluent monolayer sheet of cells
covering the surface within about a week.
The cell suspension is dispensed in bottles , tubes or
petri dishes.
Such media will enable most cell types to multiply with
a division time of 24-48 hours.
Antibiotics are added to prevent the bacterial
contaminants and phenol red as indicator.
This is supplemented with up to 5% calf or fetal calf
serum.
38. Based on their origin , chromosomal
characters and the number of generations
through which they can be maintained , cell
culture are classified into three types :
Some fastidious virus grow only in such roller
cultures.
Cell culture tubes may be incubated in a
sloped horizontal position , either as
‘stationary culture’ or may be in special ‘roller
drums’ to provide better aeration.
41. 1). Primary cell culture
Examples : Kidney cells of monkey and man , embryo
cells , alveolar cells , macrophages and amniotic cells
are usually grown in primary cell cultures.
It is capable of only limited growth and hence it can
be subcultured once or twice.
The cell culture established directly from cells taken
from animal’s tissue is called primary culture.
42. Primary cell cultures are widely used for the isolation of
animal viruses and cultivation of viruses for vaccine
production.
The culture vessel is incubated at 37⁰C for a few days to
get a primary culture.
A small volume of cell suspension is aseptically
transferred to a culture flask or petri dish containing
nutrient medium , with the help of pipette.
43. Secondary cell cultures are used for the isolation of wide group of animal
viruses and growing fastidious viruses. Some secondary cultures are used for
vaccine production.
Examples : Human embryonic kidney cells and skin fibroblast cells.
As secondary cell cultures can be maintained and subcultured for 20-50 times
, they are called semi-continuous cells.
The cell culture established from primary cell culture are called secondary
culture or sub-culture.
44. The fragments of monoculture grow into large
monolayers. These are called secondary culture.
It is then cut into small fragments. 2 or 3 fragments are
inoculated into a roller drum containing nutrient medium
and the roller drum is incubated at 37⁰C for few days.
Monolayer produced as a result of primary cell culture is
detached from the bottom of the culture flask by adding
trypsin or EDTA.
45.
46. Animal cells capable of indefinite growth are
called continuous cell lines or cell lines.
These are the cells of a single type , usually
derived from cancer cells , that are capable of
continuous serial cultivation indefinitely.
Standard cell lines derived from human
cancers , such as HeLa , HEp – 2 and KB cell
lines have been used in laboratories
throughout the world for many years.
47. These cell lines may be maintained by
serial subcultivation or stored in the cold (
-70⁰C ) for use when necessary.
Some cell lines are now permitted to be
used for vaccine manufacture, for example
: Vero cells for rabies vaccine.
48. Advantages of cell culture
Relative ease, broad spectrum, cheaper
and sensitivity
Disadvantage of cell culture
The process requires trained technicians
with experience in working on a full time
basis.
State health laboratories and hospital
laboratories do not isolate and identify
viruses in clinical work.
Tissue or serum for analysis is sent to
central laboratories to identify virus.
49. Detection of virus growth
• The following methods are available to
detect the virus growth in the cell or tissue
cultures.
a). Cytopathic effect.
b). Haemadsorption.
c). Interference.
d). Transformation.
e). Immunofluorescence.
f). Metabolic inhibition.
50. Many viruses cause morphological changes
in cultured cells in which they grow. These
changes can be readily observed by
microscopic examination of the cultures.
These changes are known as ‘cytopathic
effects’ (CPE) and the viruses causing CPE
are called ‘cytopathogenic viruses’.
The CPE produced by different groups of
viruses are characteristic and help in
presumptive identification of virus isolates.
51. • For example, enteroviruses produce
rapid CPE with crenation of cells and
degeneration entire cell sheet ; measles
virus produce syncytium formation;
herpes virus causes discrete focal
degeneration; adenovirus produce large
granular clumps of grapes.
52.
53. When hemagglutinating viruses (such as
influenza and parainfluenza viruses) grow
in cell cultures, their presence can be
indicated by the addition of guinea pig
erythrocytes to the cultures.
If the viruses are multiplying in the cultures,
the erythrocytes will adsorb onto the surface
of cells. This is known as
‘hemadsorption’.
54.
55. 3). Interference
• The growth of first virus will inhibit second
virus infection due to some inhibitory
effect. This property of cell cultures is
celled interference. it is useful to detect
the growth of non-cytopathic viruses in cell
cultures
56. 4). Transformation
• If oncogenic viruses are inoculated into
cell cultures, the infected cell grow fast
and produce microtumours in the culture.
This is called transformation. It indicated
the presence of oncogenic viruses in the
culture.
57. 5). Immunofluorescence test
• Some cell from the cell culture are stained
with a fluorescent dye conjugated antiserum
and viewed under an UV microscope.
• Viral antigen present on the cell surface bind
with the antiserum.
• Fluorescence from the cell is the positive
indication for presence of virus in the cell.
This is a widely used method in diagnostic
virology.
59. 6). Metabolic inhibition
In normal cell cultures, the medium
turns acid due to the cellular
metabolism.
When viruses grow in cell cultures , the
cell metabolism is inhibited and there is
no acid production.
This can be made out by the indicator
(phenol red) incorporated in the
medium.