Lyssavirus
Rhabdoviridae Infections
Chiroptera
Viverridae
Rabies virus
Rabies
Rhabdoviridae
Kyrgyzstan
RNA 3' Polyadenylation Signals
Bites and Stings
Australian bat lyssavirus infection in a captive juvenile black flying fox. (1/89)
The newly emerging Australian bat lyssavirus causes rabieslike disease in bats and humans. A captive juvenile black flying fox exhibited progressive neurologic signs, including sudden aggression, vocalization, dysphagia, and paresis over 9 days and then died. At necropsy, lyssavirus infection was diagnosed by fluorescent antibody test, immunoperoxidase staining, polymerase chain reaction, and virus isolation. Eight human contacts received postexposure vaccination. (+info)Lyssavirus glycoproteins expressing immunologically potent foreign B cell and cytotoxic T lymphocyte epitopes as prototypes for multivalent vaccines. (2/89)
Truncated and chimeric lyssavirus glycoprotein (G) genes were used to carry and express non-lyssavirus B and T cell epitopes for DNA-based immunization of mice, with the aim of developing a multivalent vaccine prototype. Truncated G (GPVIII) was composed of the C-terminal half (aa 253-503) of the Pasteur rabies virus (PV: genotype 1) G containing antigenic site III and the transmembrane and cytoplasmic domains. The chimeric G (GEBL1-PV) was composed of the N-terminal half (aa 1-250) of the European bat lyssavirus 1 (genotype 5) G containing antigenic site II linked to GPVIII. Antigenic sites II and III are involved in the induction of virus-neutralizing antibodies. The B cell epitope was the C3 neutralization epitope of the poliovirus type 1 capsid VP1 protein. The T cell epitope was the H2d MHC I-restricted epitope of the nucleoprotein of lymphocytic choriomeningitis virus (LCMV) involved in the induction of both cytotoxic T cell (CTL) production and protection against LCMV. Truncated G carrying foreign epitopes induced weak antibody production against rabies and polio viruses and provided weak protection against LCMV. In contrast, the chimeric plasmid containing various combinations of B and CTL epitopes elicited simultaneous immunological responses against both parental lyssaviruses and poliovirus and provided good protection against LCMV. The level of humoral and cellular immune responses depended on the order of the foreign epitopes inserted. Our results demonstrate that chimeric lyssavirus glycoproteins can be used not only to broaden the spectrum of protection against lyssaviruses, but also to express foreign B and CTL epitopes. The potential usefulness of chimeric lyssavirus glycoproteins for the development of multivalent vaccines against animal diseases and zoonoses, including rabies, is discussed. (+info)A panel of monoclonal antibodies targeting the rabies virus phosphoprotein identifies a highly variable epitope of value for sensitive strain discrimination. (3/89)
A recombinant rabies virus phosphoprotein fusion product (GST-P) was used to generate a series of monoclonal antibodies (MAbs) with anti-P reactivity. Competitive binding assays classified 27 of these MAbs into four groups (I to IV), and 24 of them were deemed to recognize linear epitopes, as judged by their reaction in immunoblots. The linear epitope recognized in each case was mapped by using two series of N- and C-terminally deleted recombinant phosphoproteins. Assessment of the reactivities of representative MAbs to a variety of lyssavirus isolates by an indirect fluorescent antibody test indicated that group I MAbs, which recognized a highly conserved N-terminal epitope, were broadly cross-reactive with all lyssaviruses assayed, while group III MAbs, which reacted with a site overlapping that of group I MAbs, exhibited variable reactivities and group IV MAbs reacted with most isolates of genotypes 1, 6, and 7 only. In contrast, group II MAbs, which recognized an epitope located within a highly divergent central portion of the protein, were exquisitely strain specific. These anti-P MAbs are potentially useful tools for lyssavirus identification and discrimination. (+info)Potential exposure to Australian bat lyssavirus, Queensland, 1996-1999. (4/89)
Two human deaths caused by Australian bat lyssavirus (ABL) infection have been reported since 1996. Information was obtained from 205 persons (mostly adults from south Brisbane and the South Coast of Queensland), who reported potential ABL exposure to the Brisbane Southside Public Health Unit from November 1,1996, to January 31, 1999. Volunteer animal handlers accounted for 39% of potential exposures, their family members for 12%, professional animal handlers for 14%, community members who intentionally handled bats for 31%, and community members with contacts initiated by bats for 4%. The prevalence of Lyssavirus detected by fluorescent antibody test in 366 sick, injured, or orphaned bats from the area was 6%. Sequelae of exposure, including the requirement for expensive postexposure prophylaxis, may be reduced by educating bat handlers and the public of the risks involved in handling Australian bats. (+info)Cytoplasmic dynein LC8 interacts with lyssavirus phosphoprotein. (5/89)
Using a yeast two-hybrid human brain cDNA library screen, the cytoplasmic dynein light chain (LC8), a 10-kDa protein, was found to interact strongly with the phosphoprotein (P) of two lyssaviruses: rabies virus (genotype 1) and Mokola virus (genotype 3). The high degree of sequence divergence between these P proteins (only 46% amino acid identity) favors the hypothesis that this interaction is a common property shared by all lyssaviruses. The P protein-dynein LC8 interaction was confirmed by colocalization with laser confocal microscopy in infected cells and by coimmunoprecipitation. The dynein-interacting P protein domain was mapped to the 186 amino acid residues of the N-terminal half of the protein. Dynein LC8 is a component of both cytoplasmic dynein and myosin V, which are involved in a wide range of intracellular motile events, such as microtubule minus-end directed organelle transport in axon "retrograde transport" and actin-based vesicle transport, respectively. Our results provide support for a model of viral nucleocapsid axoplasmic transport. Furthermore, the role of LC8 in cellular mechanisms other than transport, e.g., inhibition of neuronal nitric oxide synthase, suggests that the P protein interactions could be involved in physiopathological mechanisms of rabies virus-induced pathogenesis. (+info)Production and neurotropism of lentivirus vectors pseudotyped with lyssavirus envelope glycoproteins. (6/89)
We investigated the production efficiency and the gene transfer capacity in the central nervous system of HIV-1-based vectors pseudotyped with either the G protein of the Mokola lyssaviruses (MK-G), a neurotropic virus causing rabies disease, or the vesiculo-stomatitis G protein (VSV-G). Both envelopes induced syncitia in cell cultures. They were incorporated into vector particles and mature virions were observed by electron microscopy. Vector production was two- to sixfold more efficient with VSV-G than with MK-G. For equivalent amounts of physical particles, vector titration was 5- to 25-fold higher with VSV-G than with MK-G pseudotypes on cultured cells, and in vivo gene expression in mouse brain was more intense. Thus, VSV-G pseudotypes were produced more efficiently and were more infectious than MK-G pseudotypes. Tropism for brain cells was analyzed by intrastriatal injections in rats. Both pseudotypes preferentially transduced neurons (70-90% of transduced cells). Retrograde axonal transport was investigated by instilling vector suspensions in the rat nasal cavity. Both pseudotypes were efficiently transported to olfactive neuron bodies. Thus, although coating HIV-1 particles with rabdhovirus envelope glycoproteins enables them to enter neuronal cells efficiently, pseudotyping is not sufficient to confer the powerful neurotropism of lyssaviruses to lentivirus vectors. (+info)Host switching in Lyssavirus history from the Chiroptera to the Carnivora orders. (7/89)
Lyssaviruses are unsegmented RNA viruses causing rabies. Their vectors belong to the Carnivora and Chiroptera orders. We studied 36 carnivoran and 17 chiropteran lyssaviruses representing the main genotypes and variants. We compared their genes encoding the surface glycoprotein, which is responsible for receptor recognition and membrane fusion. The glycoprotein is the main protecting antigen and bears virulence determinants. Point mutation is the main force in lyssavirus evolution, as Sawyer's test and phylogenetic analysis showed no evidence of recombination. Tests of neutrality indicated a neutral model of evolution, also supported by globally high ratios of synonymous substitutions (d(S)) to nonsynonymous substitutions (d(N)) (>7). Relative-rate tests suggested similar rates of evolution for all lyssavirus lineages. Therefore, the absence of recombination and similar evolutionary rates make phylogeny-based conclusions reliable. Phylogenetic reconstruction strongly supported the hypothesis that host switching occurred in the history of lyssaviruses. Indeed, lyssaviruses evolved in chiropters long before the emergence of carnivoran rabies, very likely following spillovers from bats. Using dated isolates, the average rate of evolution was estimated to be roughly 4.3 x 10(-4) d(S)/site/year. Consequently, the emergence of carnivoran rabies from chiropteran lyssaviruses was determined to have occurred 888 to 1,459 years ago. Glycoprotein segments accumulating more d(N) than d(S) were distinctly detected in carnivoran and chiropteran lyssaviruses. They may have contributed to the adaptation of the virus to the two distinct mammal orders. In carnivoran lyssaviruses they overlapped the main antigenic sites, II and III, whereas in chiropteran lyssaviruses they were located in regions of unknown functions. (+info)Functional interaction map of lyssavirus phosphoprotein: identification of the minimal transcription domains. (8/89)
Lyssaviruses, the causative agents of rabies encephalitis, are distributed in seven genotypes. The phylogenetically distant rabies virus (PV strain, genotype 1) and Mokola virus (genotype 3) were used to develop a strategy to identify functional homologous interactive domains from two proteins (P and N) which participate in the viral ribonucleoprotein (RNP) transcription-replication complex. This strategy combined two-hybrid and green fluorescent protein-reverse two-hybrid assays in Saccharomyces cerevisiae to analyze protein-protein interactions and a reverse genetic assay in mammalian cells to study the transcriptional activity of the reconstituted RNP complex. Lyssavirus P proteins contain two N-binding domains (N-BDs), a strong one encompassing amino acid (aa) 176 to the C terminus and a weak one in the 189 N-terminal aa. The N-terminal portion of P (aa 52 to 189) also contains a homomultimerization site. Here we demonstrate that N-P interactions, although weaker, are maintained between proteins of the different genotypes. A minimal transcriptional module of the P protein was obtained by fusing the first 60 N-terminal aa containing the L protein binding site to the C-terminal strong N-BD. Random mutation of the strong N-BD on P protein identified three highly conserved K residues crucial for N-P interaction. Their mutagenesis in full-length P induced a transcriptionally defective RNP. The analysis of homologous interactive domains presented here and previously reported dissections of the P protein allowed us to propose a model of the functional interaction network of the lyssavirus P protein. This model underscores the central role of P at the interface between L protein and N-RNA template. (+info)Lyssavirus is a genus of viruses in the family Rhabdoviridae, order Mononegavirales. This genus includes several species of viruses that are closely related to the rabies virus and can cause similar diseases in various mammals, including humans. The lyssaviruses are bullet-shaped viruses with a single strand of negative-sense RNA. They infect nerve cells and spread through the nervous system, causing encephalitis, which is inflammation of the brain.
The most well-known member of this genus is the rabies virus, which is responsible for the disease rabies in humans and animals worldwide. Other members of this genus include Australian bat lyssavirus (ABLV), Duvenhage virus (DUVV), European bat lyssavirus types 1 and 2 (EBLV-1 and EBLV-2), Irkut virus (IRKV), Lagos bat virus (LBV), Mokola virus (MOKV), and Shimoni bat virus (SHIBV). These viruses are primarily found in bats, but some have been known to infect other mammals as well.
Prevention of lyssavirus infection is similar to that of rabies and includes avoiding contact with bats or other potential carriers, vaccinating domestic animals against rabies, and seeking prompt medical attention if a bite or scratch from a potentially infected animal occurs. Post-exposure prophylaxis (PEP) with rabies vaccine and immunoglobulin is also recommended for individuals who have been exposed to a lyssavirus.
Rhabdoviruses are negative-sense, single-stranded RNA viruses that belong to the family Rhabdoviridae. They have a wide host range, including humans, and can cause various diseases.
Rhabdoviridae infections refer to the infectious diseases caused by rhabdoviruses. The most well-known member of this family is the rabies virus, which causes rabies, a fatal zoonotic disease that affects warm-blooded animals, including humans. Rabies is transmitted through the saliva of infected animals, usually via bites or scratches.
Other rhabdoviruses can also cause human diseases, such as:
1. Vesicular stomatitis virus (VSV): It primarily affects livestock, causing vesicular lesions in the mouth and on the feet. However, it can also infect humans, causing flu-like symptoms or a rash around the mouth and hands.
2. Chandipura virus: This rhabdovirus is associated with acute encephalitis, particularly in children. It is transmitted through mosquitoes and has been identified in several countries, including India and Nigeria.
3. Human basalotid fibroblast growth factor (bFGF) receptor-binding virus: This recently discovered rhabdovirus was found to be associated with a case of acute respiratory illness. More research is needed to understand its epidemiology, transmission, and clinical significance.
Prevention and control measures for Rhabdoviridae infections include vaccination against rabies, public education on avoiding contact with potentially infected animals, and personal protective measures such as wearing gloves when handling animals or their tissues.
Chiroptera is the scientific order that includes all bat species. Bats are the only mammals capable of sustained flight, and they are distributed worldwide with the exception of extremely cold environments. They vary greatly in size, from the bumblebee bat, which weighs less than a penny, to the giant golden-crowned flying fox, which has a wingspan of up to 6 feet.
Bats play a crucial role in many ecosystems as pollinators and seed dispersers for plants, and they also help control insect populations. Some bat species are nocturnal and use echolocation to navigate and find food, while others are diurnal and rely on their vision. Their diet mainly consists of insects, fruits, nectar, and pollen, although a few species feed on blood or small vertebrates.
Unfortunately, many bat populations face significant threats due to habitat loss, disease, and wind turbine collisions, leading to declining numbers and increased conservation efforts.
Viverridae is not a medical term, but a taxonomic family in the order Carnivora, which includes mammals that are primarily carnivores. This family includes various species of civets, genets, and linsangs, among others. These animals are mostly found in Africa and Asia, and they have diverse habits and diets, with some being more arboreal and insectivorous while others are terrestrial and carnivorous.
While Viverridae is not a medical term, understanding the classification of animals can be important in medicine, particularly in veterinary medicine and public health, as it helps to identify potential risks associated with different species and their interactions with humans and other animals.
Rabies is a viral disease that affects the nervous system of mammals, including humans. It's caused by the rabies virus (RV), which belongs to the family Rhabdoviridae and genus Lyssavirus. The virus has a bullet-shaped appearance under an electron microscope and is encased in a lipid envelope.
The rabies virus primarily spreads through the saliva of infected animals, usually via bites. Once inside the body, it travels along nerve fibers to the brain, where it multiplies rapidly and causes inflammation (encephalitis). The infection can lead to symptoms such as anxiety, confusion, hallucinations, seizures, paralysis, coma, and ultimately death if left untreated.
Rabies is almost always fatal once symptoms appear, but prompt post-exposure prophylaxis (PEP), which includes vaccination and sometimes rabies immunoglobulin, can prevent the disease from developing when administered after an exposure to a potentially rabid animal. Pre-exposure vaccination is also recommended for individuals at high risk of exposure, such as veterinarians and travelers visiting rabies-endemic areas.
Rabies is a viral zoonotic disease that is typically transmitted through the saliva of infected animals, usually by a bite or scratch. The virus infects the central nervous system, causing encephalopathy and ultimately leading to death in both humans and animals if not treated promptly and effectively.
The rabies virus belongs to the Rhabdoviridae family, with a negative-sense single-stranded RNA genome. It is relatively fragile and cannot survive for long outside of its host, but it can be transmitted through contact with infected tissue or nerve cells.
Initial symptoms of rabies in humans may include fever, headache, and general weakness or discomfort. As the disease progresses, more specific symptoms appear, such as insomnia, anxiety, confusion, partial paralysis, excitation, hallucinations, agitation, hypersalivation (excessive saliva production), difficulty swallowing, and hydrophobia (fear of water).
Once clinical signs of rabies appear, the disease is almost always fatal. However, prompt post-exposure prophylaxis with rabies vaccine and immunoglobulin can prevent the onset of the disease if administered promptly after exposure. Preventive vaccination is also recommended for individuals at high risk of exposure to the virus, such as veterinarians, animal handlers, and travelers to areas where rabies is endemic.
Rhabdoviridae is a family of negative-sense, single-stranded RNA viruses that include several important human and animal pathogens. The name "Rhabdoviridae" comes from the Greek word "rhabdos," meaning rod, which refers to the characteristic bullet shape of these virions.
The family Rhabdoviridae is divided into six genera: Vesiculovirus, Lyssavirus, Ephemerovirus, Novirhabdovirus, Cytorhabdovirus, and Sphericalvirus. The most well-known member of this family is the rabies virus, which belongs to the genus Lyssavirus.
Rhabdoviruses have a simple structure, consisting of an envelope surrounding a helical nucleocapsid that contains the RNA genome. The virions are typically 100-430 nm in length and 45-100 nm in diameter, with a central electron-dense core surrounded by a less dense matrix protein layer.
Rhabdoviruses infect a wide range of hosts, including mammals, birds, fish, reptiles, and insects. They typically cause acute infections characterized by fever, lethargy, and other nonspecific symptoms. In severe cases, rhabdovirus infections can lead to serious neurological disorders, such as encephalitis or meningitis, and can be fatal if left untreated.
Transmission of rhabdoviruses occurs through various routes, depending on the specific virus and host. For example, rabies virus is typically transmitted through the bite of an infected animal, while other rhabdoviruses may be spread through contact with contaminated bodily fluids or aerosols.
Prevention and control measures for rhabdovirus infections depend on the specific virus and host. For example, rabies vaccination is effective in preventing infection in humans and animals, while other rhabdoviruses may be controlled through quarantine measures, insect control, or antiviral therapy.
I'm sorry for any confusion, but "Kyrgyzstan" is not a medical term. It is the name of a country located in Central Asia. If you have any questions about medical terms or concepts, I would be happy to help clarify those for you.
RNA 3' polyadenylation signals are specific sequences found in the DNA that direct the addition of a string of adenine (A) nucleotides to the 3' end of RNA transcripts during the process of polyadenylation. This process is an essential step in the maturation and stabilization of messenger RNA (mRNA) in eukaryotic cells.
The canonical polyadenylation signal consists of a highly conserved AAUAAA sequence, located 10-30 nucleotides upstream of the poly(A) site, where the addition of the poly(A) tail begins. This sequence is recognized by the cleavage and polyadenylation specificity factor (CPSF), which initiates the endonucleolytic cleavage of the pre-mRNA at the poly(A) site.
Following cleavage, another protein complex, including poly(A) polymerase (PAP) and nuclear poly(A)-binding protein (PABPN1), adds approximately 200-250 adenine nucleotides to the 3' end of the RNA transcript. This poly(A) tail plays a crucial role in mRNA stability, export from the nucleus, and translation efficiency.
There are also additional weak or non-canonical polyadenylation signals that can direct polyadenylation, albeit with lower efficiency. These alternative polyadenylation sites can lead to variations in the length of the 3' untranslated region (3' UTR) and may impact mRNA stability, localization, and translation.
"Bites and stings" is a general term used to describe injuries resulting from the teeth or venomous secretions of animals. These can include:
1. Insect bites: The bite marks are usually small, punctate, and may be accompanied by symptoms such as redness, swelling, itching, and pain. Examples include mosquito, flea, bedbug, and tick bites.
2. Spider bites: Some spiders possess venomous fangs that can cause localized pain, redness, and swelling. In severe cases, systemic symptoms like muscle cramps, nausea, vomiting, and difficulty breathing may occur. The black widow and brown recluse spiders are notorious for their venomous bites.
3. Snake bites: Venomous snakes deliver toxic saliva through their fangs, which can lead to local tissue damage, swelling, pain, and potentially life-threatening systemic effects such as paralysis, bleeding disorders, and respiratory failure.
4. Mammal bites: Animal bites from mammals like dogs, cats, and wild animals can cause puncture wounds, lacerations, and crush injuries. They may also transmit infectious diseases, such as rabies.
5. Marine animal stings: Stings from jellyfish, sea urchins, stingrays, and other marine creatures can result in localized pain, redness, swelling, and systemic symptoms like difficulty breathing, muscle cramps, and altered heart rhythms. Some marine animals' venoms can cause severe allergic reactions or even death.
Treatment for bites and stings varies depending on the type and severity of the injury. It may include wound care, pain management, antibiotics to prevent infection, and in some cases, antivenom therapy to counteract the effects of venom. Seeking immediate medical attention is crucial in severe cases or when systemic symptoms are present.
Rabies vaccines are medical products that contain antigens of the rabies virus, which stimulate an immune response in individuals who receive them. The purpose of rabies vaccines is to prevent the development of rabies, a viral disease that is almost always fatal once symptoms appear.
There are two primary types of rabies vaccines available:
1. Pre-exposure prophylaxis (PrEP) vaccines: These vaccines are given to individuals who are at high risk of coming into contact with the rabies virus, such as veterinarians, animal handlers, and travelers visiting areas where rabies is common. The vaccine series typically consists of three doses given over a period of 28 days.
2. Post-exposure prophylaxis (PEP) vaccines: These vaccines are administered to individuals who have already been exposed to the rabies virus, usually through a bite or scratch from an infected animal. The vaccine series typically consists of four doses given over a period of 14 days, along with a dose of rabies immune globulin (RIG) to provide immediate protection while the immune system responds to the vaccine.
Both types of rabies vaccines are highly effective at preventing the disease, but it is essential to receive them as soon as possible after exposure or before potential exposure, as the virus can be fatal if left untreated.