What is toxoplasmosis? Toxoplasmosis is an infection caused by a single-celled parasite called Toxoplasma gondii. While the parasite is found throughout the world, more than 40 million people in the United States may be infected with the Toxoplasma parasite.
Anthrax is also known as Wool sorter's disease and is zoonotic in nature. The organism responsible for this disease has been discussed here. The organism has also been used in bioterrorism attacks.
Ascariasis is an infection of the small intestine caused by Ascaris lumbricoides, a species of roundworm. Infections have no symptoms in more than 85% of cases, especially if the number of worms is small. Symptomatic ascariasis may manifest as growth retardation, pneumonitis, intestinal obstruction, or hepatobiliary and pancreatic injury.
Zoonotic disease caused by Bacillus anthracis
Infects primarily herbivores- goats, sheep, cattle, horses and swine
Human infections - contact with infected animals or contaminated animal products
Human infections rarely via the respiratory or gastrointestinal tracts
Anthrax is also known as Wool sorter's disease and is zoonotic in nature. The organism responsible for this disease has been discussed here. The organism has also been used in bioterrorism attacks.
Ascariasis is an infection of the small intestine caused by Ascaris lumbricoides, a species of roundworm. Infections have no symptoms in more than 85% of cases, especially if the number of worms is small. Symptomatic ascariasis may manifest as growth retardation, pneumonitis, intestinal obstruction, or hepatobiliary and pancreatic injury.
Zoonotic disease caused by Bacillus anthracis
Infects primarily herbivores- goats, sheep, cattle, horses and swine
Human infections - contact with infected animals or contaminated animal products
Human infections rarely via the respiratory or gastrointestinal tracts
Classification of medical parasitology Lec.2.pptxnedalalazzwy
Parasitology is the scientific discipline concerned with the study of the biology of parasites and parasitic diseases, including the distribution, biochemistry, physiology, molecular biology, ecology, evolution and clinical aspects of parasites, including the host response to these agents.
Amoebiasis is an infectious disease caused by Entamoeba histolytica (E. histolytica), the common symptoms are cramping, abdominal pain, watery or bloody diarrhea, and weight loss. Sometimes patients suffer amoebiasis as an asymptomatic behavior. In 1859 scientist W.D. Lambl first described the amoebiasis vector E. histolytica. In developing countries, millions of people die due to amoebiasis. A doctor diagnosed the disease detection of E. histolytic antigen in stool or antibodies against the parasite in serum. Metronidazole, tinidazole, lodoquinol, diloxanide furoate are given for amoebiasis patients. In this review, we have summarized the statistics, pathogenesis, diagnosis, prevention, and treatment strategy of amoebiasis disease. It also gives information about the life cycle of E. histolytica.
Morphology, Life cycle, Clinical manifestations and laboratory diagnosis of E. histolytica from Clinical and Microbiological point of view for UG and PG Students.
توثيق مراجع البحث العلمي على أنو: "إثبات ادلصادر البيانات وادلعلومات ونسبها إىلnedalalazzwy
عترب البحث العلمي ادلمنهج ذاك الذي يستويف يف مجيع مراحلو مراعاة معايري البحث العلمي ادلنهجي
خاصة فيما خيص األمانة يف اعتماد ادلراجع سواء كانت دراسات سابقة او مراجع لبعض االقتباسلت والعبارات
وزبتلف عملية التوثيق للمراجع باختالف مصدرىا ونوعها واختالف رلال زبصصها فتوثيق التت ملال خيتلف
عنو يف توثيق ادلقاالت الصحفية وخيتلف عن توثيق ادلواد االلتًتونية وىذه األخرية خيتلف يف توثيقها تبعا ألنواعها
ىي األخرى واذلدف من ذلك ىو حفاظ الباحث على سهولة العودة اىل ادلصادر وادلراجع ادلستخدمة بالنسبة
لقراء حبقو العلمي وىو أيضا من باب األمانة العلمية
A single nucleotide polymorphism (abbreviated SNP, pronounced snip) is a genomic variant at a single base position in the DNA. Scientists study if and how SNPs in a genome influence health, disease, drug response and other traits.
Mycology is the branch of biology concerned with the study of fungi, including their genetic and biochemical properties, their taxonomy and their use to humans, including as a source for tinder, traditional medicine, food, and entheogens, as well as their dangers, such as toxicity or infection.
Rabies virus, scientific name Rabies lyssavirus, is a neurotropic virus that causes rabies in humans and animals. Rabies transmission can occur through the saliva of animals and less commonly through contact with human saliva. Rabies lyssavirus, like many rhabdoviruses, has an extremely wide host range.
Immunofluorescence (IF) is a technique that permits visualization of virtually many components in any given tissue or cell type. This broad capability is achieved through combinations of specific antibodies tagged with fluorophores. Consequently, the pos
fastidious organism is any organism that has complex or particular nutritional requirements. In other words, a fastidious organism will only grow when specific nutrients are included in its medium.
An antigen is any substance that causes your immune system to produce antibodies against it. This means your immune system does not recognize the substance, and is trying to fight it off. An antigen may be a substance from th
Multiplex PCR is a technique whereby PCR is used to amplify several different DNA sequences simultaneously. It is a type of target enrichment approach. It was first described in 1988 as a method to detect deletion mutations in the dystrophin gene – the largest known human gene
Radio Immuno Assay, Immuno Fluorescent Test, Lab 4.pptxnedalalazzwy
A RIA is a very sensitive in vitro assay technique used to measure concentrations of substances, usually measuring antigen concentrations (for example, hormone .
What is enzyme-linked immunosorbent assay?
A laboratory technique that uses antibodies linked to enzymes to detect and measure the amount of a substance in a solution, such as serum. The test is done using a solid surface to which the antibodies and other molecules stick.
Infectious diseases can be viral, bacterial, parasitic or fungal infections. There's also a rare group of infectious diseases known as transmissible spongiform encephalopathies (TSEs).
Integrons are genetic elements that contain a site-specific recombination system able to integrate, express and exchange specific DNA elements, called gene cassettes. 5. The complete integron is not considered to be a mobile element as such as it lacks functions for self-mobility.
Mycoplasma pneumoniae are bacteria that can cause illness by damaging the lining of the respiratory system (throat, lungs, windpipe). People can have the bacteria in their nose or throat at one time or another without being ill. People spread Mycoplasma pneumoniae bacteria to others by coughing or sneezing.
A microarray is a laboratory tool used to detect the expression of thousands of genes at the same time. DNA microarrays are microscope slides that are printed with thousands of tiny spots in defined positions, with each spot containing a known DNA sequence or gene.
Cloning is a technique scientists use to make exact genetic copies of living things. Genes, cells, tissues, and even whole animals can all be cloned. Some clones already exist in nature. Single-celled organisms like bacteria make exact copies of themselves each time they reproduce.
A cell cycle is a series of events that takes place in a cell as it grows and divides. A cell spends most of its time in what is called interphase, and during this time it grows, replicates its chromosomes, and prepares for cell division. The cell then leaves interphase, undergoes mitosis, and completes its division.
Polymerase chain reaction (abbreviated PCR) is a laboratory technique for rapidly producing (amplifying) millions to billions of copies of a specific segment of DNA, which can then be studied in greater detail.
Assay of sodium hydroxide solution.pptxnedalalazzwy
sodium hydroxide is useful for its ability to alter fats. It is used to make soap and as a main ingredient in household products such as liquid drain cleaners. Sodium hydroxide is usually sold in pure form as white pellets or as a solution in water.
What is statistical analysis? It's the science of collecting, exploring and presenting large amounts of data to discover underlying patterns and trends. Statistics are applied every day – in research, industry and government – to become more scientific about decisions that need to be made.
New Drug Discovery and Development .....NEHA GUPTA
The "New Drug Discovery and Development" process involves the identification, design, testing, and manufacturing of novel pharmaceutical compounds with the aim of introducing new and improved treatments for various medical conditions. This comprehensive endeavor encompasses various stages, including target identification, preclinical studies, clinical trials, regulatory approval, and post-market surveillance. It involves multidisciplinary collaboration among scientists, researchers, clinicians, regulatory experts, and pharmaceutical companies to bring innovative therapies to market and address unmet medical needs.
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.
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
HOT NEW PRODUCT! BIG SALES FAST SHIPPING NOW FROM CHINA!! EU KU DB BK substit...GL Anaacs
Contact us if you are interested:
Email / Skype : kefaya1771@gmail.com
Threema: PXHY5PDH
New BATCH Ku !!! MUCH IN DEMAND FAST SALE EVERY BATCH HAPPY GOOD EFFECT BIG BATCH !
Contact me on Threema or skype to start big business!!
Hot-sale products:
NEW HOT EUTYLONE WHITE CRYSTAL!!
5cl-adba precursor (semi finished )
5cl-adba raw materials
ADBB precursor (semi finished )
ADBB raw materials
APVP powder
5fadb/4f-adb
Jwh018 / Jwh210
Eutylone crystal
Protonitazene (hydrochloride) CAS: 119276-01-6
Flubrotizolam CAS: 57801-95-3
Metonitazene CAS: 14680-51-4
Payment terms: Western Union,MoneyGram,Bitcoin or USDT.
Deliver Time: Usually 7-15days
Shipping method: FedEx, TNT, DHL,UPS etc.Our deliveries are 100% safe, fast, reliable and discreet.
Samples will be sent for your evaluation!If you are interested in, please contact me, let's talk details.
We specializes in exporting high quality Research chemical, medical intermediate, Pharmaceutical chemicals and so on. Products are exported to USA, Canada, France, Korea, Japan,Russia, Southeast Asia and other countries.
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
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.
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
2. • Like most of the Apicomplexa, Toxoplasma is an obligate
intracellular parasite. Its life cycle includes two phases
called the intestinal-enteric and Extraintestinal phases.
• Infects a wide range of animals, birds but does not appear to
cause disease in them
• The intestinal phase occurs in cats only (wild as well as
domesticated cats) and produces "oocysts."
• The extraintestinal phase occurs in all infected animals
produces "tachyzoites" and, eventually, "bradyzoites" or
“tissue cysts.“
• The disease toxoplasmosis can be transmitted by ingestion
of oocysts (in cat feces) or bradyzoites (in raw or
undercooked meat).
• A disease of the blood and lymphatic system.
• Primary problem is a congenital infection of fetus, resulting in
either a stillbirth or a child with severe brain damage or vision
problems.
3/27/2023
Lecture Eight
3. 3/27/2023
Lecture Eight
Transmission
• Eating undercooked, contaminated meat (especially
pork, lamb, and venison).
• Accidental ingestion of undercooked, contaminated
meat after handling it and not washing hands
thoroughly (Toxoplasma cannot be absorbed through
intact skin).
• Eating food that was contaminated by knives,
utensils, cutting boards and other foods that have
had contact with raw, contaminated meat.
• Drinking water contaminated with Toxoplasma
gondii.
4. 3/27/2023
Lecture Eight
• Accidentally swallowing the parasite through contact
with cat feces that contain Toxoplasma. This might
happen by
• cleaning a cat's litter box when the cat has shed
Toxoplasma in its feces
• touching or ingesting anything that has come into
contact with cat feces that contain Toxoplasma
• accidentally ingesting contaminated soil (e.g., not
washing hands after gardening or eating unwashed
fruits or vegetables from a garden)
• Mother-to-child (congenital) transmission.
• Receiving an infected organ transplant or infected
blood via transfusion, though this is rare.
6. Morphologically different stages:
• Trophozoite: or Tachyzoite is crescent or banana
shaped with a pointed end and a bluntly round end.
• In the acute stage of the disease, trophozoites are
usually scattered in the blood, cerebrospinal fluid and
various pathological exudates arranged in pairs or singly.
• The trophozoite community is within a host cell
parasitophorous vacuole not surrounded by a cystic
wall. Hence they are also known as a pseudocyst
(usually a swelling macrophage with a several
parasites).
• The trophozoites within a pseudocyst are Tachyzoites.
3/27/2023
Lecture Eight
7. • Tissue cyst: is round and oval in
appearance and the cystic wall created by
the parasite is thin, but firm and elastic.
• The protozoa multiply in the tissue cyst
slowly and repeatedly.
• The trophozoites in the cyst are called
Bradyzoites, which are similar to the
Tachyzoites, but smaller than them.
3/27/2023
Lecture Eight
8. Tissue cysts of Toxoplasma gondii filled with
bradyzoites
3/27/2023
Lecture Eight
As host resistance develops, usually around 3 weeks post infection, tissue cysts
may form in many organs, primarily in brain and muscle
9. • Schizont: can be found in the small intestinal mucosa of
the infected cat.
• Schizonts contain about 4-40 merozoites.
• Gametocytes are also found in the small intestinal
mucosa of the cat.
• Male gametocytes produce 12-32 male gametes,
crescent in shape.
• The female gametocyte develops into a female gamete.
• Male and female gametes fertilize to form a zygote that
develops into an oocyst.
• oocyst is round or elleptic and covered with a smooth
transparent cystic wall consisting of two layers.
• Each mature oocyst contains two sporocysts with each
sporocyst containing 4 sporozoites.
3/27/2023
10. • Two different kinds of host are needed in the
sexual and asexual generations present in the life
cycle of T. gondii.
• Sexual development or Gametogony occurs in the
epithelial cells of the small intestine of cats(intra-
intestinal phase).
• The binary fission and endodyogeny ( process of
internal budding in which two daughter cells are
formed within the body of the mother cell that
dies when the progeny are released) of the asexual
development takes place in various nucleated cells
outside the intestine of many spp. Of mammals
and birds.
3/27/2023
Lecture Eight
11. Life Cycle
The life cycle of the parasite consists of 3 stages as follows
(a)Tachyzoites, the multiplying that which invade and multiply
within cells,
(b)Bradyzoites,the slowly multiplying inside tisssue cysts,
seen during latent and chronic infection.
(c)Sporozoites inside oocysts, which are shed in cat feces and
remain in the environment.
In cats, which are definitive hosts. both schizogony and
gametogony takeplace in the epithelial cells of the small
intestine (enteric cycle). Cat is infected either by ingestion
of oocyst shed in its faeces or by eating flesh of other
animals or birds containing tissue cysts
The oocysts produced by gametogony are shed in faeces.
They develop into infective forms in soil or water.
3/27/2023
Lecture Eight
12. When ingested by other animals, birds or human.
which are intermediate hosts. The oocysts release
sporozoites which infect the intestinal epithelial cells.
Here, they multiply by endodyogeny to form
tachyzoites. The host cell ruptures releasing numerous
trophozoites which spread through blood and lymph
infecting any type of nucleated cell in various tissues
and organs. This is known as the exoenteric cycle.
Primary infection with the parasite may be
asymptomatic, acute or chronic. In chronic infections
tissue cysts are produced within muscles and other
tissues.
3/27/2023
Lecture Eight
13. • When other intermediate hosts ingest these tissue
cysts, the asexual cycle is repeated. When cats ingest
the tissue cysts they become infected and in them
both asexual and sexual cycles are repeated
• Artificial methods of human infection are laboratory
contamination, blood transfusion and organ
transplantation. Congenital infection also occurs.
When food or water contaminated with T.gondii
oocyst or animal body containing cysts, pseudocyst
ingested by a feline, sporozoites, bradyoites or
Tachyzoites are released in the small intestine. These
parasites invade the epithelial cells.
3/27/2023
Lecture Eight
16. Pathogenesis
• The Tacyzoites have predilection for parenchymal
cells and Reticulo endothelial system and directly
destroys the cells.
• Humans are relatively resistant to infection
• But low grade infection of lymph node persists
• When tissue cysts ruptures – releases number of
Bradyzoites
• Local hypersensitivity reaction may cause
inflammation.
• Causes blocking of blood vessels
• Causes death of cells near damaged area
3/27/2023
Lecture Eight
17. Clinical Features
Most human infections are asymptomatic. Clinical toxoplasmosis
may be congenital or acquired.
Congenital Toxoplasmosis
Congenital toxoplasmosis results when infection is
transmitted transplacentally from mother to fetus. The risk
of fetal infection rises with the progress of gestation, from
25 per cent when the mother acquires primary infection in
the first trimester, to 65 per cent in the third trimester.
Conversely the severity of foetal damage is highest when
infection is transmitted in early pregnancy. Mothers with
chronic or latent Toxoplasma infection acquired earlier do
not ordinarily infect their babies, but in some women with
latent or chronic infection may be to babies.
3/27/2023
Lecture Eight
18. the tissue cyst may be reactivated during pregnancy and
liberate trophozoites which may reach the fetus in utero.
Most infected newborns are asymptomatic at birth and may
remain so throughout. Some develop clinical manifestations
of toxoplasmosis weeks, months or even years after birth.
The manifestations may be chorioretinitis, strabismus,
blindness, deafness, epilepsy or mental retardation. A few
are born with manifestations of acute toxoplasmosis, which
may include fever, jaundice, diarrhoea, hydrocephalus,
microcephaly,cerebralcalcifications,cataract,glaucoma,chori
oretinitis, optic atrophy, lymphadenitis, pneumonitis,
myocarditis and hepatosplenomegaly.
3/27/2023
Lecture Eight
19. Acquired Toxoplasmosis
Infection acquired postnatally is mostly asymptomatic. The most
common manifestation of acute acquired toxoplasmosis is
lymphadenopathy, Fever, headache, myalgia and splenomegaly. The
illness may resemble mild ‘flu’ or infectious mononucleosis
lymphadenopathy may persist. In some there may be a typhus-
like,with pneumonitis, myocarditis and meningoencephalitis, which
may be fatal.
Another type of toxoplasmosis is ocular. Approximately 35 per cent of
cases of chorioretinitis .
Toxoplasmosis primarily involving the central nervous system is usually
fatal and often found in AIDS, severely in the immunodeficient, brain
involvement is common.
Host defense against Toxoplasma infection involves both humoral and
cellular responses. Specific IgG antibody can lyse extracellular
trophozoites. But activated T cells and natural killer cells appear to be
more important in containing the infection and preventing clinical
disease.
3/27/2023
Lecture Eight
21. Congenital toxoplasmosis is a problem in 1-5/1000 pregnancies
• If a woman is infected for the first
time during pregnancy the parasite
can cross the placenta and cause
fetal disease.
• Both the* probability and severity
of the disease depend on when
the infection takes place during
pregnancy.
• Early: low transmission, but severe
disease
• Late: high transmission, more
benign symptoms.
Hydrocephaly.
* Intracerebral calcification.
22. Diagnosis
Laboratory diagnosis may be made by microscopic demonstration of the
parasite, by its isolation or by serological tests. Giemsa stained impression
smears of lymphnodes, bone marrow, spleen or brain may occasionally
show the trophozoites, which can be readily identified by their morphology.
Inoculation of tissue culture and animal :
T. gondii can also be isolated by inoculation of tissue, also can be
isolated by intraperitoneal inoculation of body fluids or ground
tissues into young laboratory mice that are free from infection. If no
death occurs, the mice are observed for about six weeks ,and tail or
heart blood is then tested for specific antibody. The diagnosis is
confirmed by demonstration of tissue cysts in the brain of inoculated
mice.
Polymerase chain reaction :Toxoplasmal DNA can be detected in the
specimens by PCR.
3/27/2023
Lecture Eight
23. 3/27/2023
Lecture Eight
Skin test results showing delayed skin hypersensitivity to Toxoplasma gondii
antigens.
Serology:
1. Sabin –Feldman dye test:
This test depends upon the appearance in 2-3 weeks of antibodies that
render the membrane of laboratory –cultured living T. gondii
impermeable to alkaline methylen blue, so that organisms are unstained
in the presence of positive serum. It is one of the first methods used to
diagnose toxoplasmosis. This highly sensitive and specific test is a
complement – mediated neutralizing antigen –antibody reaction. It is
performed in reference laboratories.
2-Latex agglutination test:
It is a simple test. It shows 94 % agreement with the dye test. The latex
particles are coated with inactivated T. gondii soluble antigen. This test
does not require heat inactivation of serum samples.
24. 3/27/2023
Lecture Eight
3 – Other tests :
The most common method of laboratory diagnosis is by serology. Several serological
tests are available. Indirect immunofluorescence, indirect haemagglutination,
complement fixation ,ELISA.
The standard test used now is ELISA, separately for IgM and IgG antibodies. The
presence of IgM antibody in the absence of IgG denotes current infection, IgM
antibody with high titre IgG suggests infection in the recent past; Negative IgM with
positive IgG indicates past infection. This is subject to individual variation.
In some cases IgM antibody may persist up to 18 months. Serial ELISA provides
better information than a single test.
Diagnosis of congenital toxoplasmosis can be established by:
•PCR: PCR of the amniotic fluid to detect the B1 gene of the parasite.
•Serology: The presence of IgM ( which dose not cross the placenta ) in the infant̕s
circulation is diagnostic but often this is not found . Specific IgG in the infant̕s
circulation may be maternal origin or due to infection. Testing of infant̕s blood at 2
monthly intervals will show whether the IgG antibody level is decreasing . At 6- 10
months the infant̕s circulation should not contain maternal IgG and therefore
persistence of IgG beyond this time is indicative of infection in the infant.
25. Amniocentesis
• Done around 16th week of pregnancy
• A long needle is inserted into the Amniotic sac and
amniotic fluid is drawn.
26. Treatment
• Combination of Pyramethamine and Sulphadiazine
or Trisulfapyramidines
• Other alternative Drugs
Spiramycin
Clindamycin
Trimethoprim – Sulphmethoxazole
In pregnancy – Spriamycin is recommended drug
3/27/2023
Lecture Eight
27. Control of Toxoplasmosis
• Avoidance of human
contact with Cat feces is
highly important measure.
• Changing of Cat litter and
safe disposal can prevent
transmission
• Pregnant women should
avoid contact with kittens
3/27/2023
Lecture Eight
28. Screening of pregnant women
• Periodic screening of pregnant
women with high risk for IgG
and IgM antibodies to
Toxoplasmosis is recommended
3/27/2023
Lecture Eight
Care of the Meat
• Avoid eating raw or
undercooked meat.
• Freezing < -200c
• Heating at 500c for 4-6
minutes destroys the cysts
and sterilizes the meat.