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Query: UMLS:C1175175 (
SARS
)
19,188
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Transmission electron microscopy has had a profound impact on our knowledge and understanding of viruses and bacteria. The 1000-fold improvement in resolution provided by electron microscopy (EM) has allowed visualization of viruses, the existence of which had previously only been suspected as the causative agents of transmissible infectious disease. Viruses are grouped into families based on their morphology. Viruses from different families look different and these morphological variances are the basis for identification of viruses by EM. Electron microscopy initially came to prominence in diagnostic microbiology in the late 1960s when it was used in the rapid diagnosis of smallpox, by differentiating, on a morphological basis, poxviruses from the less problematic herpesviruses in skin lesions. Subsequently, the technique was employed in the diagnosis of other viral infections, such as hepatitis B and parvovirus
B19
. Electron microscopy has led to the discovery of many new viruses, most notably the various viruses associated with gastroenteritis, for which it remained the principal diagnostic method until fairly recent times. Development of molecular techniques, which offer greater sensitivity and often the capacity to easily process large numbers of samples, has replaced EM in many areas of diagnostic virology. Hence the role of EM in clinical virology is evolving with less emphasis on diagnosis and more on research, although this is likely only to be undertaken in specialist centres. However, EM still offers tremendous advantages to the microbiologist, both in the speed of diagnosis and the potential for detecting, by a single test, any viral pathogen or even multiple pathogens present within a sample. There is continuing use of EM for the investigation of new and emerging agents, such as
SARS
and human monkeypox virus. Furthermore, EM forms a vital part of the national emergency response programme of many countries and will provide a frontline diagnostic service in the event of a bioterrorism incident, particularly in the scenario of a deliberate release of smallpox virus. In the field of bacteriology, EM is of little use diagnostically, although some bacterial pathogens can be identified in biopsy material processed for EM examination. Electron microscopy has been used, however, to elucidate the structure and function of many bacterial features, such as flagellae, fimbriae and spores and in the study of bacteriophages. The combined use of EM and gold-labelled antibodies provides a powerful tool for the ultrastructural localisation of bacterial and viral antigens.
...
PMID:Application of transmission electron microscopy to the clinical study of viral and bacterial infections: present and future. 1636 Nov 3
Viral infections can cause many glomerular diseases. The diagnostic criteria for virus-related nephropathy include detailed clinical and laboratory data, and tissue molecular analysis. Several mechanisms are involved in the pathogenesis of virus-related nephropathy, including tropism of the virus in the kidney, induction of abnormal immune complexes, direct cytopathogenic effects, and multiorgan failure. Hepatitis B virus is associated with membranous nephropathy and mesangiocapillary glomerulonephritis in endemic areas. Hepatitis C virus causes various forms of glomerulonephritis, including cryoglobulinemia-mediated glomerulonephritis. Infection with HIV is associated with a collapsing focal segmental glomerulosclerosis, a distinctive disease that affects mainly Africans and African Americans. In the course of HIV infection, other types of immune complex glomerulonephritis can occur, most frequently in whites. Recent reports indicate a role for parvovirus
B19
in 'idiopathic' collapsing focal segmental glomerulosclerosis. Both hantaviruses, and coronaviruses associated with
severe acute respiratory syndrome
, can lead to acute renal failure. Renal biopsy followed by appropriate serological and molecular testing is essential for defining virus-related glomerular lesions and guiding prognostic and therapeutic evaluation.
...
PMID:Viral nephropathy. 1693 38
Two main types of safety procedures must be applied to biological products, including plasma derivatives: (i) preventive procedures and (ii) elimination procedures. Prevention includes epidemiological control of donor populations; checks on each donor's health condition; analysis of each donation for the main pathogens using serological methods; additional analysis of all plasma for human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis A virus (HAV) and the
B19
virus, using nucleic acid amplification techniques (NAT). A 60 days or longer inventory hold of all plasma donations is applied, to allow additional time to discard previous donations from potential seroconverting or otherwise rejectable donors. Elimination procedures minimize the low residual risk of transmitting pathogens, including unknown or previously undetected ones. Since the introduction 20 years ago of solvent-detergent treatment, very effective against enveloped viruses (HIV, HBV, HCV, West Nile virus,
SARS
, avian influenza virus etc), there have been no known cases of transmission of this type of pathogens by products manufactured according to this procedure. Other inactivation procedures such as pasteurization, dry-heat or nanofiltration may prove equally effective. In addition, dry-heat treatment and nanofiltration are capable of effectively eliminating non-enveloped viruses (HAV,
B19
virus). Recent studies show that the
B19
virus is much more sensitive to heat (in lyophilized state or by pasteurization) and acid pH than previously thought. Although there is no evidence for the transmission of classic transmissible spongiform encephalopathies (TSEs) through blood or blood-products transfusion, four possible cases have been reported in the United Kingdom involving transmission by non-leukoreduced blood components of the agent that causes variant Creutzfeldt-Jakob Disease (vCJD), a disease linked to the outbreak of bovine spongiform encephalopathy (BSE) which took place in that country. However, there are no cases of human TSE (classic or variant) transmission by plasma-derived products. Analytical methods capable of detecting the vCJD agent in patients' brains (where high titres are found) and other tissues (such as the spleen, appendix and lymph nodes, where much lower concentrations are found) are unable to detect the agent in blood or plasma from patients with vCJD, even in the clinical phase of the disease. Experiments by Grifols and other groups show that the capacity of the production processes to eliminate vCJD agent models is many orders of magnitude greater than the maximum expected load of the agent. In this regard, the efficacy of precipitation, affinity chromatography, depth filtration and nanofiltration are particularly notable.
...
PMID:Safety procedures of coagulation factors. 1807 96
The introduction of blood donor screening by virus nucleic acid amplification technology (NAT) in the mid to late 1990s was driven by the so-called AIDS and hepatitis C virus (HCV) epidemic, with thousands of recipients of infected blood products and components. Plasma fractionators were the first to introduce NAT testing besides pathogen reduction procedures, to reduce the virus transmission risk through their products. To achieve a similar safety standard, NAT was then also introduced for labile blood components. German transfusion centres were the first to start in-house NAT testing of their donations in pools of up to 96 samples for HCV, hepatitis B virus (HBV), and human immunodeficiency virus-1 (HIV-1). Years later the diagnostics industry provided commercial HCV and HIV-1 and later HBV NAT tests on automated platforms. NAT tests for HIV-2, hepatitis A virus, and Parvovirus
B19
followed, again driven by transfusion centres with their in-house tests. When
severe acute respiratory syndrome
corona virus (SARS-CoV) and West Nile Virus emerged it was the NAT that enabled the manufacturers and transfusion centres to instantly introduce sensitive and specific screening tests. Subsequent automation including sample preparation has significantly reduced the costs and complexity of the procedure and made it affordable to middle income countries as well. Currently more than 60 million donations per year are NAT tested worldwide and the remaining residual risk of virus transmission by blood components and products could be reduced to almost zero. Automation rendered possible the reduction of pool size in conjunction with increased throughput and sensitivity. Thus, antibody and antigen testing may be dispensable in the long run, particularly in the combination of NAT testing with pathogen reduction. There are new technologies on the horizon like digital droplet PCR, next-generation sequencing, lab-on-a-chip, and digital antigen assays, which are comparably sensitive. However, each of these has limitations, either in throughput, costs, automation, time to result, specificity, or the need for NAT as an integral part of the technology. Thus, NAT is still the shortest and most efficient means to the result. Donor screening NAT also contributed significantly to our knowledge on how fast viruses replicate, and on the respective diagnostic window. In conjunction with animal and patient studies, we have learned more about the minimal infectious dose and the epidemics in the donor population.
...
PMID:History and Future of Nucleic Acid Amplification Technology Blood Donor Testing. 3119 Nov 92
Viral myocarditis has been identified as a major cause of dilated cardiomyopathy (DCM) that can lead to heart failure. Historically, Coxsackieviruses and adenoviruses have been commonly suspected in myocarditis/DCM patients in North America and Europe. However, this notion is changing as other viruses such as Parvovirus
B19
and human herpesvirus-6 are increasingly reported as causes of myocarditis in the United States, with the most recent example being the
severe acute respiratory syndrome
coronavirus 2, causing the Coronavirus Disease-19. The mouse model of Coxsackievirus B3 (CVB3)-induced myocarditis, which may involve mediation of autoimmunity, is routinely used in the study of immune pathogenesis of viral infections as triggers of DCM. In this review, we discuss the immune mechanisms underlying the development of viral myocarditis with an emphasis on autoimmunity in the development of post-infectious myocarditis induced with CVB3.
...
PMID:An overview of the immune mechanisms of viral myocarditis. 3272 Apr 61
APOBEC3 enzymes are innate immune effectors that introduce mutations into viral genomes. These enzymes are cytidine deaminases which transform cytosine into uracil. They preferentially mutate cytidine preceded by thymidine making the 5'TC motif their favored target. Viruses have evolved different strategies to evade APOBEC3 restriction. Certain viruses actively encode viral proteins antagonizing the APOBEC3s, others passively face the APOBEC3 selection pressure thanks to a depleted genome for APOBEC3-targeted motifs. Hence, the APOBEC3s left on the genome of certain viruses an evolutionary footprint. The aim of our study is the identification of these viruses having a genome shaped by the APOBEC3s. We analyzed the genome of 33,400 human viruses for the depletion of APOBEC3-favored motifs. We demonstrate that the APOBEC3 selection pressure impacts at least 22% of all currently annotated human viral species. The papillomaviridae and polyomaviridae are the most intensively footprinted families; evidencing a selection pressure acting genome-wide and on both strands. Members of the parvoviridae family are differentially targeted in term of both magnitude and localization of the footprint. Interestingly, a massive APOBEC3 footprint is present on both strands of the
B19
erythroparvovirus; making this viral genome one of the most cleaned sequences for APOBEC3-favored motifs. We also identified the endemic coronaviridae as significantly footprinted. Interestingly, no such footprint has been detected on the zoonotic MERS-CoV,
SARS
-CoV-1 and
SARS
-CoV-2 coronaviruses. In addition to viruses that are footprinted genome-wide, certain viruses are footprinted only on very short sections of their genome. That is the case for the gamma-herpesviridae and adenoviridae where the footprint is localized on the lytic origins of replication. A mild footprint can also be detected on the negative strand of the reverse transcribing HIV-1, HIV-2, HTLV-1 and HBV viruses. Together, our data illustrate the extent of the APOBEC3 selection pressure on the human viruses and identify new putatively APOBEC3-targeted viruses.
...
PMID:Footprint of the host restriction factors APOBEC3 on the genome of human viruses. 3279 3
Myocarditis is well known to be caused by viral infections such as Coxsackie virus group B, human herpes virus 6 and parvovirus
B19
. However, during the current emerging outbreak of
SARS
-CoV-2, there have been few case reports describing myocarditis as a possible presentation. In our case report we describe, early cardiac manifestations of
SARS
-CoV-2 in a UK District General Hospital. A 44-year-old Caucasian woman without any comorbidities presented with
SARS
-CoV-2 related fulminant myocarditis without initial respiratory symptoms. Patient underwent treatment with milrinone and methylprednisolone that showed reduction in myocardial inflammation and significantly improved myocardial contractility. This was then followed by a second phase of
SARS
-CoV-2 associated pneumonia and renal failure requiring ventilatory support and haemofiltration. Although, not described in the literature, we have found conjunctive use of milrinone and methylprednisolone effective in patient with
SARS
-CoV-2 fulminant myocarditis.
...
PMID:Fulminant myocarditis as an early presentation of SARS-CoV-2. 3292 10
Chilblain-like acral lesions have been identified in some coronavirus disease 2019 (COVID-19) patients. It has been suggested that these pseudo-chilblains could be a specific marker of
severe acute respiratory syndrome
coronavirus 2 (SARS-CoV-2) infection. Most patients with these lesions have had negative polymerase chain reactions (PCRs), but some authors believe serology tests are likely to give positive results. We designed a prospective study including all patients with pseudo-chilblains treated in outpatient department in April and May 2020 and then performed
SARS
-CoV-2 PCR and serology tests on all available patients. We evaluated 59 patients, of whom 17 had undergone PCR before the study period, all with negative results. For the present study, we performed 20 additional PCRs, serology tests in 25 patients, and a parvovirus
B19
antibody test in 15 patients. All results were negative. Our findings counter the hypothesis that serology is likely to reveal
SARS
-CoV-2 infection in patients with pseudo-chilblains. One hypothesis for our negative results is that the time period between symptom onset and antibody production is longer in these patients; another is that the lesions are caused by behavioral changes during lockdown rather than
SARS
-CoV-2 infection. We nevertheless maintain that COVID-19 should be ruled out in people presenting with chilblain-like lesions.
...
PMID:No SARS-CoV-2 antibody response in 25 patients with pseudo-chilblains. 3297 45
BACKGROUND Acute generalized exanthematous pustulosis (AGEP) is a rare exanthem characterized by the abrupt onset of numerous small, non-follicular, sterile pustules arising on an erythematous base. AGEP is often associated with medications; however, it has also been connected to various viral infections including cytomegalovirus, parvovirus
B19
, and Epstein-Barr virus. Coronavirus disease 2019 (COVID-19) has been associated with a variety of skin findings, including erythematous or patchy rash, urticaria, hives, blisters, petechiae, livedo reticularis, and even AGEP in a patient undergoing treatment with hydroxychloroquine. CASE REPORT A 78-year-old man with a past medical history of benign prostatic hyperplasia, coronary artery disease, and atrial fibrillation presented with septic shock secondary to a urinary tract infection. On day 7 of treatment with cefepime, he became febrile and developed a pustular rash and persistent hypotension without any respiratory symptoms. Subsequently, he was diagnosed with COVID-19. Skin biopsy of the rash revealed AGEP. CONCLUSIONS AGEP is an uncommon cutaneous eruption often triggered by medications and viruses. AGEP is thought to be mediated by pro-inflammatory cells and cytokines. This report describes an unusual presentation of AGEP following treatment with cefepime for a urinary tract infection in a 78-year-old man who was found to be positive for
SARS
-CoV-2 infection, but was not treated with hydroxychloroquine. Although AGEP has been described in association with some viral infections, it is more commonly a drug-associated dermatosis, commonly seen during treatment with antibiotics. As in this case, AGEP usually resolves after discontinuation of the offending antibiotic.
...
PMID:Delayed Presentation of Acute Generalized Exanthematous Pustulosis Following Treatment with Cefepime in a Patient with COVID-19 without the Use of Hydroxychloroquine. 3309 83
Pain is a common health problem all around the world. The pain symptoms are various depending on the underlying disease or the direct cause of pain itself. Viral infection could cause arthralgia or acute-onset arthritis, moreover in pandemic era of
SARS
-CoV-2 infection. The patients might experience arthritis, arthralgia, joint pain, or musculoskeletal pain. Viral infection including parvovirus
B19
, hepatitis virus, human immunodeficiency virus, arthropod-borne virus, and coronavirus could cause various types of pain. The pathogenesis of these symptoms is similar to each other despite of different causative organism. This review will discuss about pain caused by various causative organisms.
...
PMID:Pain related viral infections: a literature review. 3316 60
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