A prion is a protein that can fold in multiple, structurally distinct ways, at least one of which is transmissible to other prion proteins. It is this form of replication that leads to disease that is similar to viral infection. The word prion, coined in 1982 by Stanley B. Prusiner, is short for “proteinaceous infectious particle” derived from the words protein and infection, in reference to a prion's ability to self-propagate and transmit its conformation to other prions. While several yeast proteins have been identified as having prionogenic properties, the first prion protein was discovered in mammals and is referred to as the major prion protein (PrP). This infectious agent causes mammalian transmissible spongiform encephalopathies, including bovine spongiform encephalopathy (BSE, also known as "mad cow disease") and scrapie in sheep. In humans, PrP causes Creutzfeldt-Jakob Disease (CJD), variant Creutzfeldt-Jakob Disease (vCJD), Gerstmann–Sträussler–Scheinker syndrome, Fatal Familial Insomnia and kuru.
Protein is a vital element for the molecules in our cells. Prion disease starts off very slow in the blood, but once it has reached peak levels it creates symptoms quickly and will spread rapidly through the brain.
A prion is a protein that can fold in multiple, structurally distinct ways, at least one of which is transmissible to other prion proteins. It is this form of replication that leads to disease that is similar to viral infection. The word prion, coined in 1982 by Stanley B. Prusiner, is short for “proteinaceous infectious particle” derived from the words protein and infection, in reference to a prion's ability to self-propagate and transmit its conformation to other prions. While several yeast proteins have been identified as having prionogenic properties, the first prion protein was discovered in mammals and is referred to as the major prion protein (PrP). This infectious agent causes mammalian transmissible spongiform encephalopathies, including bovine spongiform encephalopathy (BSE, also known as "mad cow disease") and scrapie in sheep. In humans, PrP causes Creutzfeldt-Jakob Disease (CJD), variant Creutzfeldt-Jakob Disease (vCJD), Gerstmann–Sträussler–Scheinker syndrome, Fatal Familial Insomnia and kuru.
Protein is a vital element for the molecules in our cells. Prion disease starts off very slow in the blood, but once it has reached peak levels it creates symptoms quickly and will spread rapidly through the brain.
Prions: structure diseases associated with and clinical picuture.pptxKhalidJahir1
a lecture that describes what are prions, what diseases they cause, and how they cause disease, incubation period and symptoms and signs of the disease they cause.
PRIONS-structure, multiplication, diseases.pptxRASHMI M G
PRIONS are infectious agents composed primarily of sialoglycoprotein.
This protein is called prion protein (PrP)
They contain no nucleic acid.
They cause a variety of neurodegenerative diseases in humans and animals.
According to STANLEY PRUSINER,
Prions- ‘which means proteinaceous and infectious (-on by analogy to virion) that lacks nucleic acid’.
It refers to a previously undescribed form of infection due to protein misfolding . While the infectious agent was named prion, and the specific protein that make the prion was named PrP i.e. ‘protease resistant protein’.
PRIONS proteins in the form of fibres which also occur as fold rods.
The normal protein found in a variety of tissues is referred to as PrPC (C refers to cellular or common PrP), whereas the misfolded form of PrPC is called PrPSc which is responsible for the formation of amyloid plaques that results in neurodegeneration.
PrPSc is the infectious form of PrPC, (Sc refers to scrapie, a prion disease occurring in sheep) .
PrPc is a Alpha helical while PrPSc is a beta pleated sheet
PrPc do not contain beta sheet.
PrPc protein can adopt 2 distinct different stable conformations.
All known prions induce the formation of an amyloid fold in which the protein polymerizes into an aggregate consisting of tightly packed beta sheets.
This altered structure is extremely stable and accumulates in the infected tissue causing cell death and tissue damage resulting in death of animals.
It is supposed that the diseased form of PRION (PrPSc) originated spontaneously or transmitted through ingestion of food/feed directly interacts with the normal endogenous form PrPC and enables to rearrange its structure.
As a result of interaction the normal form PrPC is converted to abnormal form (PrPSc) .
It is assumed that an unidentified cellular protein (protein X) helps the conversion of PrPC to PrPSc by bringing a molecule of each of the two together into a complex.
Main reason for the cause of prions is ‘cannibalism’ i.e. eating of one human by another human.
2 types of cannibalism – endocannibalism (eating humans from the same community) and exocannibalism ( eating humans from other communities).
The tribal ground up the brain into a pale grey soup, heated it and ate it.
Therefore, ingestion of brain tissue of dead relatives for religious reasons was likely the route of transmission.
In cattles
-BOVINE SPONGIFORM ENCEPHALOPATHY
(mad cow disease).
2. In humans
-ALZHEIMER’S DISEASE
DOWN’S SYNDROME
FATAL FAMILIAL INSOMNIA
KURU LEPROSY
Misfolded proteins which catalyses the refolding of the native protein into the misfolded pathogenic forms are called as Prions. They are responsible for fatal neurodegenerative diseases. Some of the neurodegenerative diseases such as Scrapie, BSE, CWD of animals and Kuru, CJD, Fatal familial insomnia of human beings are included in the presentation.
Prions: structure diseases associated with and clinical picuture.pptxKhalidJahir1
a lecture that describes what are prions, what diseases they cause, and how they cause disease, incubation period and symptoms and signs of the disease they cause.
PRIONS-structure, multiplication, diseases.pptxRASHMI M G
PRIONS are infectious agents composed primarily of sialoglycoprotein.
This protein is called prion protein (PrP)
They contain no nucleic acid.
They cause a variety of neurodegenerative diseases in humans and animals.
According to STANLEY PRUSINER,
Prions- ‘which means proteinaceous and infectious (-on by analogy to virion) that lacks nucleic acid’.
It refers to a previously undescribed form of infection due to protein misfolding . While the infectious agent was named prion, and the specific protein that make the prion was named PrP i.e. ‘protease resistant protein’.
PRIONS proteins in the form of fibres which also occur as fold rods.
The normal protein found in a variety of tissues is referred to as PrPC (C refers to cellular or common PrP), whereas the misfolded form of PrPC is called PrPSc which is responsible for the formation of amyloid plaques that results in neurodegeneration.
PrPSc is the infectious form of PrPC, (Sc refers to scrapie, a prion disease occurring in sheep) .
PrPc is a Alpha helical while PrPSc is a beta pleated sheet
PrPc do not contain beta sheet.
PrPc protein can adopt 2 distinct different stable conformations.
All known prions induce the formation of an amyloid fold in which the protein polymerizes into an aggregate consisting of tightly packed beta sheets.
This altered structure is extremely stable and accumulates in the infected tissue causing cell death and tissue damage resulting in death of animals.
It is supposed that the diseased form of PRION (PrPSc) originated spontaneously or transmitted through ingestion of food/feed directly interacts with the normal endogenous form PrPC and enables to rearrange its structure.
As a result of interaction the normal form PrPC is converted to abnormal form (PrPSc) .
It is assumed that an unidentified cellular protein (protein X) helps the conversion of PrPC to PrPSc by bringing a molecule of each of the two together into a complex.
Main reason for the cause of prions is ‘cannibalism’ i.e. eating of one human by another human.
2 types of cannibalism – endocannibalism (eating humans from the same community) and exocannibalism ( eating humans from other communities).
The tribal ground up the brain into a pale grey soup, heated it and ate it.
Therefore, ingestion of brain tissue of dead relatives for religious reasons was likely the route of transmission.
In cattles
-BOVINE SPONGIFORM ENCEPHALOPATHY
(mad cow disease).
2. In humans
-ALZHEIMER’S DISEASE
DOWN’S SYNDROME
FATAL FAMILIAL INSOMNIA
KURU LEPROSY
Misfolded proteins which catalyses the refolding of the native protein into the misfolded pathogenic forms are called as Prions. They are responsible for fatal neurodegenerative diseases. Some of the neurodegenerative diseases such as Scrapie, BSE, CWD of animals and Kuru, CJD, Fatal familial insomnia of human beings are included in the presentation.
Medical Technology Tackles New Health Care Demand - Research Report - March 2...pchutichetpong
M Capital Group (“MCG”) predicts that with, against, despite, and even without the global pandemic, the medical technology (MedTech) industry shows signs of continuous healthy growth, driven by smaller, faster, and cheaper devices, growing demand for home-based applications, technological innovation, strategic acquisitions, investments, and SPAC listings. MCG predicts that this should reflects itself in annual growth of over 6%, well beyond 2028.
According to Chris Mouchabhani, Managing Partner at M Capital Group, “Despite all economic scenarios that one may consider, beyond overall economic shocks, medical technology should remain one of the most promising and robust sectors over the short to medium term and well beyond 2028.”
There is a movement towards home-based care for the elderly, next generation scanning and MRI devices, wearable technology, artificial intelligence incorporation, and online connectivity. Experts also see a focus on predictive, preventive, personalized, participatory, and precision medicine, with rising levels of integration of home care and technological innovation.
The average cost of treatment has been rising across the board, creating additional financial burdens to governments, healthcare providers and insurance companies. According to MCG, cost-per-inpatient-stay in the United States alone rose on average annually by over 13% between 2014 to 2021, leading MedTech to focus research efforts on optimized medical equipment at lower price points, whilst emphasizing portability and ease of use. Namely, 46% of the 1,008 medical technology companies in the 2021 MedTech Innovator (“MTI”) database are focusing on prevention, wellness, detection, or diagnosis, signaling a clear push for preventive care to also tackle costs.
In addition, there has also been a lasting impact on consumer and medical demand for home care, supported by the pandemic. Lockdowns, closure of care facilities, and healthcare systems subjected to capacity pressure, accelerated demand away from traditional inpatient care. Now, outpatient care solutions are driving industry production, with nearly 70% of recent diagnostics start-up companies producing products in areas such as ambulatory clinics, at-home care, and self-administered diagnostics.
Empowering ACOs: Leveraging Quality Management Tools for MIPS and BeyondHealth Catalyst
Join us as we delve into the crucial realm of quality reporting for MSSP (Medicare Shared Savings Program) Accountable Care Organizations (ACOs).
In this session, we will explore how a robust quality management solution can empower your organization to meet regulatory requirements and improve processes for MIPS reporting and internal quality programs. Learn how our MeasureAble application enables compliance and fosters continuous improvement.
CRISPR-Cas9, a revolutionary gene-editing tool, holds immense potential to reshape medicine, agriculture, and our understanding of life. But like any powerful tool, it comes with ethical considerations.
Unveiling CRISPR: This naturally occurring bacterial defense system (crRNA & Cas9 protein) fights viruses. Scientists repurposed it for precise gene editing (correction, deletion, insertion) by targeting specific DNA sequences.
The Promise: CRISPR offers exciting possibilities:
Gene Therapy: Correcting genetic diseases like cystic fibrosis.
Agriculture: Engineering crops resistant to pests and harsh environments.
Research: Studying gene function to unlock new knowledge.
The Peril: Ethical concerns demand attention:
Off-target Effects: Unintended DNA edits can have unforeseen consequences.
Eugenics: Misusing CRISPR for designer babies raises social and ethical questions.
Equity: High costs could limit access to this potentially life-saving technology.
The Path Forward: Responsible development is crucial:
International Collaboration: Clear guidelines are needed for research and human trials.
Public Education: Open discussions ensure informed decisions about CRISPR.
Prioritize Safety and Ethics: Safety and ethical principles must be paramount.
CRISPR offers a powerful tool for a better future, but responsible development and addressing ethical concerns are essential. By prioritizing safety, fostering open dialogue, and ensuring equitable access, we can harness CRISPR's power for the benefit of all. (2998 characters)
The Importance of Community Nursing Care.pdfAD Healthcare
NDIS and Community 24/7 Nursing Care is a specific type of support that may be provided under the NDIS for individuals with complex medical needs who require ongoing nursing care in a community setting, such as their home or a supported accommodation facility.
One of the most developed cities of India, the city of Chennai is the capital of Tamilnadu and many people from different parts of India come here to earn their bread and butter. Being a metropolitan, the city is filled with towering building and beaches but the sad part as with almost every Indian city
1. 1 Prion disease
A prion is a protein that changes its three-dimensional shape, which can cause disease. Prions
are found in the brain and are resistant to proteases. The function of prions is not fully
understood, but they are believed to play a role in intracellular signaling and cell adhesion
Prion disease represents a group of conditions that affect the nervous system in humans and
animals. In people, these conditions impair brain function, causing changes in memory,
personality, and behavior; a decline in intellectual function (dementia); and abnormal
movements, particularly difficulty with coordinating movements (ataxia). The signs and
symptoms of prion disease typically begin in adulthood and worsen with time, leading to death
within a few months to several years.
Prion diseases or transmissible spongiform encephalopathies (TSEs) are a
family of rare progressive neurodegenerative disorders that affect both
humans and animals. They are distinguished by long incubation periods,
characteristic spongiform changes associated with neuronal loss, and a
failure to induce inflammatory response.
The causative agents of TSEs are believed to be prions. The term “prions”
refers to abnormal, pathogenic agents that are transmissible and are able to
induce abnormal folding of specific normal cellular proteins called prion
proteins that are found most abundantly in the brain. The functions of these
normal prion proteins are still not completely understood. The abnormal
folding of the prion proteins leads to brain damage and the characteristic
signs and symptoms of the disease. Prion diseases are usually rapidly
progressive and always fatal.
A prion is composed of an abnormally folded protein that causes
progressive neurodegenerative conditions, with two of the most notable
being Bovine spongiform encephalopathy (BSE or mad cow disease) seen
in cattle and livestock and Creutzfeldt-Jakob disease (CJD) seen in humans.
The most likely infection route of the acquired prion diseases is via oral intake and what follows is an
accumulation and amplification of prion infectivity in lymphoid tissues associated with the gut.
Prions are self-propagating protein aggregates that act as protein-based elements of inheritance in
fungi. Unlike other infectious agents, such as bacteria, viruses, and fungi, prions do not contain
genetic materials such as DNA or RNA. The unique traits and genetic information of prions are
believed to be encoded within the conformational structure and posttranslational modifications of the
proteins
Causes
2. Between 10 and 15 percent of all cases of prion disease are caused by mutations in the PRNP gene.
Because they can run in families, these forms of prion disease are classified as familial. Familial prion
diseases, which have overlapping signs and symptoms, include familial Creutzfeldt-Jakob disease (CJD),
Gerstmann-Sträussler-Scheinker syndrome (GSS), and fatal familial insomnia (FFI)
Frequency
These disorders are very rare. Although the exact prevalence of prion disease is unknown, studies
suggest that this group of conditions affects about one person per million worldwide each year.
Approximately 350 new cases are reported annually in the United States.
Description
Prion disease represents a group of conditions that affect the nervous system in humans and animals. In
people, these conditions impair brain function, causing changes in memory, personality, and behavior; a
decline in intellectual function (dementia); and abnormal movements, particularly difficulty with
coordinating movements (ataxia). The signs and symptoms of prion disease typically begin in adulthood
and worsen with time, leading to death within a few months to several years.
Inheritance
Familial forms of prion disease are inherited in an autosomal dominant pattern, which means one copy
of the altered PRNP gene in each cell is sufficient to cause the disorder. In most cases, an affected person
inherits the altered gene from one affected parent. In some people, familial forms of prion disease are
caused by a new mutation in the gene that occurs during the formation of a parent's reproductive cells
(eggs or sperm) or in early embryonic development. Although such people do not have an affected
parent, they can pass the genetic change to their children.
The sporadic, acquired, and iatrogenic forms of prion disease, including kuru and variant Creutzfeldt-
Jakob disease, are not inherited.
Other Names for This Condition
Inherited human transmissible spongiform encephalopathies
Prion protein diseases
Prion-associated disorders
Prion-induced disorders
Transmissible dementias
Transmissible spongiform encephalopathies
TSEs
What is the mechanism of prion disease?
3. Prion diseases are a group of infectious neurodegenerative diseases with an entirely novel mechanism of
transmission, involving a protein-only infectious agent that propagates the disease by transmitting
protein conformational changes. The disease results from extensive and progressive brain degeneration.
Human Prion Diseases
• Creutzfeldt-Jakob Disease (CJD)
• Variant Creutzfeldt-Jakob Disease (vCJD)
• Gerstmann-Straussler-Scheinker Syndrome
• Fatal Familial Insomnia
• Kuru
Animal Prion Diseases
• Bovine Spongiform Encephalopathy (BSE)
• Chronic Wasting Disease (CWD)
• Scrapie
• Transmissible mink encephalopathy
• Feline spongiform encephalopathy
• Ungulate spongiform encephalopathy
immunoresponsethe
2 THE Innate immune system ;
Prion infection does not elicit any detectable specific humoral or
cellular immunoresponse, but host innate immunity appears to be
persistently activated in infected brains, possibly for clearance of
prions. Accumulated scrapie-like prion protein (PrPSc) may further
stimulate strong non-specific
• Prion diseases occur when normal prion protein, found on the surface
of many cells, becomes abnormal and clump in the brain, causing brain
damage. This abnormal accumulation of protein in the brain can cause
memory impairment, personality changes, and difficulties with
After infection, the targeting of peripherally-acquired prions to specific
immune cells in the secondary lymphoid organs (SLO), such as the lymph
4. nodes and spleen, is essential for the efficient transmission of disease to the
brain
Prion diseases are a unique group of infectious chronic neurodegenerative
disorders to which there are no cures. Although prion infections do not
stimulate adaptive immune responses in infected individuals, the actions of
certain immune cell populations can have a significant impact on disease
pathogenesis. After infection, the targeting of peripherally-acquired prions to
specific immune cells in the secondary lymphoid organs (SLO), such as the
lymph nodes and spleen, is essential for the efficient transmission of disease
to the brain. Once the prions reach the brain, interactions with other
immune cell populations can provide either host protection or accelerate the
neurodegeneration. In this review, we provide a detailed account of how
factors such as inflammation, ageing and pathogen co-infection can affect
prion disease pathogenesis and susceptibility. For example, we discuss how
changes to the abundance, function and activation status of specific immune
cell populations can affect the transmission of prion diseases by peripheral
routes. We also describe how the effects of systemic inflammation on certain
glial cell subsets in the brains of infected individuals can accelerate the
neurodegeneration. A detailed understanding of the factors that affect prion
disease transmission and pathogenesis is essential for the development of
novel intervention strategies.
prions and prion disease, immune system, inflammation, aging, co-infection,
susceptibility
the immune system deal with prions;Surprisingly, the immune system
appears to behave as a Trojan's horse rather than a protective fortification
during prion infections. Because prions seem to be essentially composed of a
protein, PrP(Sc), identical in sequence to a host encoded protein, PrP(C), the
spe efficient transmission of disease to the brain
The part of the immune system fights prions;After infection, the targeting of
peripherally-acquired prions to specific immune cells in the secondary
lymphoid organs (SLO), such as the lymph nodes and spleen, is essential for
thecific immune system displays a natural tolerance.
5. the type of cells do prions infect;Several cell types are thought to produce
PrPSc following prion infection in vivo, including neurons, astrocytes, and
lymphoreticular cells (9, 49, 53, 134).
the role of prion protein in immune system;It is up-regulated in T cell
activation and may be expressed at higher levels by specialized classes of
lymphocyte. Furthermore, antibody cross-linking of surface PrP modulates T
cell activation and leads to rearrangements of lipid raft constituents and
increased phosphorylation of signalling proteins. Prion diseases are a unique
group of infectious chronic neurodegenerative disorders to which there are
no cures. Although prion infections do not stimulate adaptive immune
responses in infected individuals, the actions of certain immune cell
populations can have a significant impact on disease pathogenesis.