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At least 739 records · Page 41Linked to original sources
PubMed2006

Lowering standards of clinical waste management: do the hazardous waste regulations conflict with the CDC's universal/standard precautions?

Clinical waste is a costly and troublesome commodity. Comprising the detritus of medical care, the foremost hazard is the risk of infection from micro-organisms present in these wastes. Infection commonly occurs through penetrating injury, the so-called 'sharps' or 'needlestick' injury, although contamination of non-intact skin or splashes to the eye may transmit infection. Bloodborne viruses (hepatitis B, hepatitis C, human immunodeficiency virus) are the most serious threat, although respiratory, soft tissue and enteric infections are not unknown. The European Hazardous Waste Directive, that harmonizes the categorization and control of wastes, permits downregulation of clinical wastes where the risk of infection may be low. Although strengthened by the requirement for risk assessment in waste classification, UK regulatory guidance promoting classification of some clinical wastes as non-hazardous completely ignores the Centers for Disease Control and Prevention's Universal Precautions for the prevention of transmission of human immunodeficiency virus, hepatitis B virus and other bloodborne pathogens in healthcare settings, which seek to prevent bloodborne virus infection in healthcare workers and others, and the more extensive Standard Precautions that extend these principles to the prevention of healthcare-associated infections and the environmental spread of nosocomial pathogens. By creating a potent cost driver encouraging downregulation of some clinical wastes, UK legislation based on the European Hazardous Waste Directive conflicts with the CDC's Universal/Standard Precautions.

Animals↗
PubMed1999

Detection of avian leukosis virus in albumen of chicken eggs using reverse transcription polymerase chain reaction.

A reverse transcriptase polymerase chain (RT-PCR) assay was developed to detect avian leukosis retrovirus (ALV) in egg albumen. Eggs of Single Comb White Leghorns were from a commercial breeder (stock F) and from a pathogen-free flock (stock N). RT-PCR was undertaken on isolated RNA from 20 unfertilized egg samples using seven sets of primers that correspond to the ALV gp85 envelope glycoprotein which determines the ALV subgroup classification. An ELISA assay for ALV gs antigen of egg albumen was positive for all stock F birds tested and negative for all stock N birds. Virus isolation was undertaken by inoculating egg albumen, feather pulp, or blood from five stock F chickens onto cultures of chicken embryo fibroblasts (C/E). IFA analysis of the inoculated C/E cultures indicated that all stock F birds tested contained infectious ALV. For the virus-positive stock F chickens, RT-PCR analyses using primers designed to detect all ALV subgroups detected ALV in 15/15 (100%) egg albumen samples, while primers designed to detect subgroup A ALV were positive for 12/15 (80%) egg albumen samples. RT-PCR products were not detected from five egg albumen samples from five stock N chickens by any primer sets. Direct sequencing using primers specific for subgroup A ALV verified the viral subgroup in the RT-PCR amplification products. The combined use of RT-PCR and direct sequencing of the RT-PCR product provides a new approach for identifying ALV-infected poultry.

Albumins↗
PubMed2001

Emerging infectious pathogens of wildlife.

The first part of this paper surveys emerging pathogens of wildlife recorded on the ProMED Web site for a 2-year period between 1998 and 2000. The majority of pathogens recorded as causing disease outbreaks in wildlife were viral in origin. Anthropogenic activities caused the outbreaks in a significant majority of cases. The second part of the paper develops some matrix models for quantifying the basic reproductive number, R(0), for a variety of potential types of emergent pathogen that cause outbreaks in wildlife. These analyses emphasize the sensitivity of R(0) to heterogeneities created by either the spatial structure of the host population, or the ability of the pathogens to utilize multiple host species. At each stage we illustrate how the approach provides insight into the initial dynamics of emergent pathogens such as canine parvovirus, Lyme disease, and West Nile virus in the United States.

Animal Diseases↗
PubMed2006

A first global analysis of plasmid encoded proteins in the ACLAME database.

Many plasmids are mobile genetic elements (MGEs) and, as other members of that group of DNA entities, their genomes display a mosaic and combinatorial structure, making their classification extremely difficult. As other MGEs, plasmids play a major role in horizontal transfer of genetic materials and genome reorganization. Yet, the full impact of such phenomenon on major properties of the host cell, such as pathogenicity, the ability to use new carbon sources or resistance to antibiotics, remains to be fully assessed. More and more complete plasmid genome sequences are available. However, in the absence of standards for storing plasmid sequence data and annotating genes and gene products on sequenced plasmid genomes, the resulting information remains rather limited. Using 503 sequenced plasmids organized in the ACLAME database, we discuss how, by structuring information on the genomes, their host and the proteins they code for, one can gain access to either global or more detailed analysis of the plasmid sequence information, as illustrated by a network representation of the relationships between plasmids.

Bacteria↗
PubMed2004

Novel approaches and cutting edge immunotherapies in multiple sclerosis.

MS is a chronic inflammatory disease of the central nervous system (CNS). MS is a predominantly CD4+ T cell mediated autoimmune disorder. Recent studies have challenged this existing paradigm by supporting the role of other immune cells and factors (even non-immune) including CNS antigen-driven clonally expanded B cells, autoantibodies, complement and mediators of the innate immune responses in MS lesions. Further expansion of this global CNS dysfunction includes oligodendroglial cell (OGC) loss, attenuated remyelination, axonopathy, and gliosis. The recognition of new "players" directing effector and regulatory functions and further insight into reparative mechanisms occurring at various stages of the disease within a given individual will influence ongoing and future therapeutic trials. The following discussion will encompass evolving concepts in the pathogenesis of MS with a focus on novel immunotherapies. These new approaches reflect targeting of a multifaceted spectrum of immune activity. The immunotherapies will be characterized by their intervening role of specific and/or multiple pathogenic steps including initiation, peripheral activation, molecular co-stimulation and immune effector responses during early, transitional and late phases of disease. Emerging strategies for the enhancement of neuroprotection and reparative mechanisms will also be reviewed. Classification of novel approaches will include the following main types of immunotherapies: (1) targeting of myelin specific T cells: antigen-specific therapies (2) targeting of B cell and autoantibody responses (3) targeting of immunologic steps of disease pathology (4) targeting of reparative stages of disease: neurotrophic and neuroprotective, (5) global therapies: broad-based polydirectional strategies.

Animals↗
PubMed1997

[Nosocomial infections: back to the future].

The increasing rate of nosocomial infections seems to be related to the wider use of invasive procedures. Evaluation of the patient risk factors for infection, use of SIRS classification and knowledge of the setting care should be utilized for the diagnostic approach. The empiric antibiotic therapy should take in account the site of the infection (bacteremia, pneumonia, urinary tract infection etc.) and the presumed pathogen; knowledge of the local epidemiology is a pre-requisite for the antibiotics choice. Among gram-positive microorganisms, methicillin-resistant staphylococci and vancomycin-resistant enterococci are responsible of difficult to treat infections; penicillin-resistant pneumococci, largely present in some european countries, might become an emerging pathogen also in Italy. The knowledge and ability of infectious diseases specialist encompasses clinical, microbiological and epidemiological fields to play a key role in the prevention and management of nosocomial infections.

English Abstract↗
PubMed2004

Bio-ALIRT biosurveillance detection algorithm evaluation.

INTRODUCTION: Early detection of disease outbreaks by a medical biosurveillance system relies on two major components: 1) the contribution of early and reliable data sources and 2) the sensitivity, specificity, and timeliness of biosurveillance detection algorithms. This paper describes an effort to assess leading detection algorithms by arranging a common challenge problem and providing a common data set. OBJECTIVES: The objectives of this study were to determine whether automated detection algorithms can reliably and quickly identify the onset of natural disease outbreaks that are surrogates for possible terrorist pathogen releases, and do so at acceptable false-alert rates (e.g., once every 2-6 weeks). METHODS: Historic de-identified data were obtained from five metropolitan areas over 23 months; these data included International Classification of Diseases, Ninth Revision (ICD-9) codes related to respiratory and gastrointestinal illness syndromes. An outbreak detection group identified and labeled two natural disease outbreaks in these data and provided them to analysts for training of detection algorithms. All outbreaks in the remaining test data were identified but not revealed to the detection groups until after their analyses. The algorithms established a probability of outbreak for each day's counts. The probability of outbreak was assessed as an "actual" alert for different false-alert rates. RESULTS: The best algorithms were able to detect all of the outbreaks at false-alert rates of one every 2-6 weeks. They were often able to detect for the same day human investigators had identified as the true start of the outbreak. CONCLUSIONS: Because minimal data exists for an actual biologic attack, determining how quickly an algorithm might detect such an attack is difficult. However, application of these algorithms in combination with other data-analysis methods to historic outbreak data indicates that biosurveillance techniques for analyzing syndrome counts can rapidly detect seasonal respiratory and gastrointestinal illness outbreaks. Further research is needed to assess the value of electronic data sources for predictive detection. In addition, simulations need to be developed and implemented to better characterize the size and type of biologic attack that can be detected by current methods by challenging them under different projected operational conditions.

Algorithms↗
PubMed1991

[Medico-biological aspects of the problem of preventing the harmful action of pesticides].

The main principles in the prevention of pesticide health hazards are a comprehensive toxicological evaluation of new compounds to be introduced into practice and adequate hygienic regulations allowing for all sorts of pesticides' pathogenic action and various sources of their supply from the environment. In acute, subacute and chronic experiments pesticides are examined for toxicity, adverse effects on reproductive function and embryogenesis, mutagenic, carcinogenic and allergenic potential. The hygienic classification is based on the limiting criterion of the greatest damage. Safe levels are derived from the tolerance thresholds resting on persistence and changes of the shifts found, from investigations of borderline health conditions, assessment of homeostasis, hepatic immune and monooxygenase systems involved in metabolism of lipid-soluble pesticides. Animal experiments findings extrapolated to clinical conditions help to predict probable long-term responses. The directions of the research into prevention of pesticides-induced health hazards are outlined.

Animals↗
PubMedDate not supplied

Sequence analysis demonstrates the conservation of fimH and variability of fimA throughout avian pathogenic Escherichia coli (APEC).

In this study we sequenced and analysed the fimH and fimA genes of 24 avian pathogenic Escherichia coli (APEC) isolates, in order to investigate their possible conserved nature. Additional parameters (serotype, presence of aerobactin receptor, expression of F1 pili and virulence for chickens) were investigated to look for correlations with the obtained sequences. The sequence analysis demonstrated that FimH is highly conserved among all investigated APEC strains (>99% homology), whereas the major subunit FimA is less conserved, presenting 6 variable regions distributed along the protein. A hydrophilicity analysis suggested several variable domains of FimA to be potential epitopes. We were able to classify the investigated strains into three main groups, on the basis of the amino-acid sequences of the variable regions. This grouping was consistent throughout all variable regions and was independent of serotype, leading to an improved classification of the F1 pili. No correlation was found between the fimH and fimA sequences and the following parameters: avian species, organ of isolation, serotype, presence of aerobactin receptor and virulence for chickens. This study elucidated the molecular structure and the degree of conservation of FimH and FimA among various avian pathogenic E. coli strains.

Adhesins, Escherichia coli↗
PubMed2006

Identification of cell wall-associated proteins from Phytophthora ramorum.

The oomycete genus Phytophthora comprises a large group of fungal-like plant pathogens. Two Phytophthora genomes recently have been sequenced; one of them is the genome of Phytophthora ramorum, the causal agent of sudden oak death. During plant infection, extracellular proteins, either soluble secreted proteins or proteins associated with the cell wall, play important roles in the interaction with host plants. Cell walls of P. ramorum contain 1 to 1.5% proteins, the remainder almost exclusively being accounted for by glucan polymers. Here, we present an inventory of cell-wall-associated proteins based on mass spectrometric sequence analysis of tryptic peptides obtained by proteolytic digestion of sodium dodecyl sulfate-treated mycelial cell walls. In total, 17 proteins were identified, all of which are authentic secretory proteins. Functional classification based on homology searches revealed six putative mucins or mucin-like proteins, five putative glycoside hydrolases, two transglutaminases, one annexin-like protein, the elicitin protein RAM5, one protein of unknown function, and one Kazal-type protease inhibitor. We propose that the cell wall proteins thus identified are important for pathogenicity.

Algal Proteins↗
PubMed2006

Polyphasic classification of Alternaria isolated from hazelnut and walnut fruit in Europe.

Brown apical necrosis of English walnut and grey necrosis of hazelnut are destructive fruit diseases caused by a complex of opportunistic fungi including several small-spored catenulate Alternaria taxa. Thirty Alternaria isolates recovered from walnut and hazelnut fruit that were pathogenic on their respective host were compared along with type or representative isolates of A. alternata, A. tenuissima, A. arborescens, and A. infectoria using morphological and molecular criteria. Morphological examination using standardized procedures separated the walnut and hazelnut isolates into three morphological groups: the A. alternata group, the A. tenuissima group, and the A. arborescens group based upon common characteristics of the conidium and the sporulation apparatus. To evaluate genetic relationships among these groups, AFLP markers, inter simple sequence repeat (ISSR) markers, and histone gene sequence data were compared. Based upon AFLP data, the A. alternata and A. tenuissima groups comprised a single lineage, and the A. arborescens group comprised a separate lineage. ISSR data supported the grouping by AFLP data except for three isolates of the A. alternata group that clustered with the A. arborescens group. Base substitution of the H4 gene supported the discrimination of the A. arborescens group from the A. alternata and A. tenuissima groups. Tests of hypotheses based upon groupings derived from the various data sets supported the discrimination of the A. arborescens group but did not support the discrimination of the A. alternata group from the A. tenuissima group.

Alternaria↗
PubMed1988

Classification and distribution of large intestinal bacteria in nonhibernating and hibernating leopard frogs (Rana pipiens).

The large intestinal flora of the leopard frog, Rana pipiens, was examined to determine whether differences existed between the nonhibernating and hibernating states of the animal and to determine the relative concentrations and proportions of potential frog pathogens. Hibernators had a logarithmic decrease of bacteria per milligram of intestine averaging one, and significantly greater proportions of facultative bacteria and psychrophiles relative to nonhibernators. The predominant anaerobic bacteria were gram-positive Clostridium species and gram-negative Bacteroides and Fusobacterium species. The predominant facultative bacteria were enterobacteria in nonhibernators but Pseudomonas species in hibernators. Many species of Pseudomonas are pathogenic for frogs, and thus the intestinal flora in hibernators may be a potential source of infectious disease.

Anaerobiosis↗
PubMed2025

Increased yield of genetic diagnoses in inherited heart diseases using expanded genome and RNA-splicing analyses.

PURPOSE: The Australian Genomics Cardiovascular Disorders Flagship investigated genome sequencing as a first-line genetic test in 600 individuals with cardiomyopathy, primary arrhythmia syndromes, or congenital heart disease. Analysis of disease-specific virtual gene panels achieved a genetic diagnosis in 38% of participants. We sought to increase genetic diagnosis yields by analyzing lesser-evidenced disease genes, the mitochondrial genome, and by functional analysis of predicted splice-altering variants. METHODS: Genome sequences of 520 participants with cardiomyopathy or primary arrhythmia syndromes were reanalyzed in 572 cardiac genes and the mitochondrial genome. Participants with congenital heart disease were excluded. Variants predicted in silico to disrupt splicing were assessed with blood RNA and minigenes. RESULTS: A new genetic diagnosis was achieved in 4% (19/520) of participants, including deep intronic and mitochondrial genome variants. Ten participants had diagnostic variants in lesser evidenced disease genes; 9 had splicing variant pathogenicity functionally validated. Eleven participants had a newly identified variant of uncertain significance with high suspicion of pathogenicity, warranting clinical review. Our data supported the gene-disease association of 1 new cardiomyopathy gene, TBX20. CONCLUSION: Identifying new gene-disease relationships, maintaining contemporary gene panels, and integrating functional studies to refine splicing variant classifications increase genetic diagnoses for cardiomyopathies and primary arrhythmia syndromes.

Humans↗
PubMed1999

Dengue: an evaluation of dengue severity in French Polynesia based on an analysis of 403 laboratory-confirmed cases.

We conducted a retrospective study of 403 laboratory-confirmed dengue cases hospitalized in Tahiti between August 1989 and March 1997. According to standard WHO criteria, 337 of these cases were dengue fever (DF) and 64 were dengue haemorrhagic fever (DHF). Of the 10 fatal cases, 6 were DF and 4 were DHF. As an alternative, we used a correspondence analysis procedure to define dengue severity based on basic clinical and biological criteria for which we assigned a severity score, and then selected the 50 most severe cases from this analysis. Of the latter, 17 patients had been classified as DF and 33 as DHF by the WHO criteria. From this analysis, haemorrhages and decreased platelets counts associated with hepatic disorders are the main criteria associated with the severe dengue cases. Thus in our study population, the WHO classification does not account for the overall severity of dengue; hepatic failure should be considered as a specific severe form of dengue since plasma leakage, which is the pathophysiological hallmark of DHF, is only one of the pathogenic mechanisms leading to severity.

Adolescent↗
PubMed1987

Analysis of the complete nucleotide sequence of the picornavirus Theiler's murine encephalomyelitis virus indicates that it is closely related to cardioviruses.

Theiler's murine encephalomyelitis viruses (TMEV) are naturally occurring enteric pathogens of mice which constitute a separate serological group within the picornavirus family. Persistent TMEV infection in mice provides a relevant experimental animal model for the human demyelinating disease multiple sclerosis. To provide information about the TMEV classification, genome organization, and protein processing map, we determined the complete nucleotide sequence of the TMEV genome and deduced the amino acid sequence of the polyprotein coding region. The RNA genome, which is typical of the picornavirus family, is 8,098 nucleotides long. The 5' untranslated region is 1,064 nucleotides long (making it the longest in the picornavirus family after the aphthoviruses) and lacks a poly(C) tract. Computer-generated comparison of the 5' and 3' noncoding regions and polyprotein revealed the highest level of nucleotide and predicted amino acid identity between the TMEV and the cardioviruses encephalomyocarditis virus (EMCV) and Mengo virus. The TMEV polyprotein, which appears to be processed like EMCV since the amino acids flanking the putative proteolytic cleavage sites have been conserved, begins with a short leader peptide followed by 11 other gene products in the standard L-4-3-4 picornavirus arrangement. Because of these similarities, we propose that the TMEV be grouped with the cardioviruses. However, since TMEV and EMCV have different biophysical properties and show no cross-neutralization, they most likely belong in a separate cardiovirus subgroup.

Amino Acid Sequence↗
PubMed2003

Advantages of using mitochondrial 16S rDNA sequences to classify clinical isolates of Acanthamoeba.

PURPOSE: This work was intended to test the classification of Acanthamoeba into genotypes based on nuclear ribosomal RNA gene (18S rDNA, Rns) sequences. Nearly all Acanthamoeba keratitis (AK) isolates are genotype RnsT4. This marked phylogenetic localization is presumably either due to an innate potential for pathogenicity or to a peculiarity of the gene sequences used. To differentiate between these possibilities, relationships among isolates have been reexamined, using a second gene. METHODS: Phylogenetic relationships among isolates of Acanthamoeba were studied, using sequences of the mitochondrial small subunit ribosomal RNA gene (16S rDNA; rns). Genotypes based on complete sequences of approximately 1540 bp were determined for 68 strains, by using multiple phylogenetic analyses. RESULTS: Each strain's mitochondria contained a single intron-free rns sequence (allele). The 68 strains had 35 different sequences. Twenty-eight strains had unique sequences, and 40 strains each shared one of the seven remaining sequences. Eleven mitochondrial rns genotypes corresponding to 11 of 12 previously described nuclear Rns genotypes were identified. Genotype rnsT4 was subdivided into eight distinct clades, with seven including Acanthamoeba keratitis (AK) isolates. CONCLUSIONS: The phylogenetic clustering of AK isolates was confirmed and thus is not specific to the nuclear gene. Rns and rns sequences are both suitable for genotyping of ACANTHAMOEBA: However, the mitochondrial sequences are shorter and more consistent in length, have a higher percentage of alignable bases for sequence comparisons, and have none of the complications caused by multiple alleles or introns, which are occasionally found in Rns. In addition, the more common occurrence of strains with identical rns sequences simplifies identification and clustering of isolates.

Acanthamoeba↗
PubMed2000

[Trichosporon--experience with species identification from human isolates].

Among 162 human isolates of Trichosporon the author isolated according to "crucial" signs (Guého et al. 1992, 1994) the following as dominant: T. mucoides (41%) and T. asahii (33%), T. inkin, T. ovoides and others as well as non-pathogenic T. pullulans were rare in their investigation. To the originally most frequently reported type T. cutaneum belonged less than 10% of the total number of isolates. The variability of physiological and biological signs did not make classification of 5% isolated Trichosporon strains possible. The disc diffusion method confirmed resistance of the tested strains to 5-fluorocytosine, and inhibition by polyene and azole antimycotics.

Humans↗
PubMed1992

Diarrhea caused by a slow-growing Enterococcus-like agent in neonatal rats.

An enteropathogenic Enterococcus-like agent was isolated from a spontaneous outbreak of diarrhea that occurred in a colony containing neonatal rats. Diarrhea was experimentally reproduced in virus-antibody-free neonatal rats inoculated with this purified "enterococcus." Gram-positive cocci were adhered to the small intestinal villi of affected animals from which the organism was reisolated. The isolate's classification in the genus Enterococcus was confirmed by genetic probe; however, because of its unique fermentation pattern, it could not be definitively speciated. Indirect immunofluorescence assays indicate that this strain of enterococcus and Enterococcus hirae, another strain pathogenic for neonatal rats, differ antigenically. Enterococci should be considered as potential etiologic agents in outbreaks of diarrhea involving neonatal rats and future efforts directed to increasing our understanding of the pathophysiology of this disease.

Animals↗