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PubMed2003

Bacterial agents used for bioterrorism.

BACKGROUND: Bacterial pathogens and their products are potential agents of biological terrorism and biological warfare. These agents can be deployed through simple aerosol delivery systems and thereby cause widespread disease and death. METHODS: This report is a review of bacterial species that have been employed for development of biological terrorism, relying on a system for classification of their threat developed by the Centers for Disease Control. RESULTS: Physicians must understand how to recognize early signs and symptoms caused by bacterial agents. Clinical findings often seen on presentation are emphasized along with a summary of therapeutic approaches. CONCLUSIONS: Initiation of immediate therapy and supportive care provides the best chance for survival from these potentially lethal and devastating infections. A high index of suspicion must be maintained, especially in the setting of a sudden influx of cases with what are often relatively nonspecific symptoms.

Animals↗
PubMed1986

Virulence characteristics of Aeromonas spp. in relation to source and biotype.

The significance of Aeromonas spp. as potential water-borne enteric pathogens in Tasmania, Australia, an area with a mild climate and comparatively low year-round water temperatures, was investigated in view of the reported marked peak of Aeromonas-associated gastroenteritis in the summer and the apparent influence of temperature on levels of potentially pathogenic species in water supplies. Biochemical characteristics and virulence-associated properties--exotoxin production (hemolysin, enterotoxin), ability to grow at 43 degrees C, and possession of pili--were determined for 105 Tasmanian isolates of Aeromonas spp.; 43 isolates were from clinical specimens (greater than 75% diarrhea associated) and 62 were from water. Current classification schemes were evaluated for these isolates. A. sobria comprised 35% of the clinical isolates and 16% of the water isolates, A. hydrophila comprised 56 and 79%, and A. caviae comprised 9 and 5%. A total of 42% of the clinical isolates and 15% of the environmental isolates were enterotoxigenic (by the suckling mouse assay); these levels were significantly lower than those found in warmer environments. The majority (74%) of enterotoxigenic isolates were A. sobria. Enterotoxin-producing isolates possessed three or more of the following properties. They were Voges-Proskauer positive, did not hydrolyze arabinose, were positive for lysine decarboxylase, were able to grow at 43 degrees C, and produced large amounts of hemolysin (titer, greater than 128). Thus, the biochemical scheme proposed by Burke et al. (V. Burke, J. Robinson, H.M. Atkinson, and M. Gracey, J. Clin. Microbiol. 15:48-52, 1982) for identifying enterotoxigenic isolates appears to have widespread applicability. Environmental enterotoxigenic isolates possessed numerous pili, but these appeared to be lost once infection was established, as a similar isolates from patients with diarrhea were poorly piliated.

Aeromonas↗
PubMed2000

Reprocessing anesthesia instruments and devices.

Reprocessing anesthesia instruments and devices can often present a challenge for anesthesia providers because anesthesia devices have become more complex, cross-contamination with disease-forming pathogens can occur, and the importance of appropriate reprocessing may not be fully understood. Based on accepted practice recommendations, regulations, and research, reprocessing must be performed by skilled individuals who understand asepsis, cleaning, disinfection, and sterilization principles. This article describes the art of reprocessing and includes highlighted information on recommended practices, Spaulding's classifications, personal protective attire, precleaning, leak testing of flexible endoscopes, device disassembly, cleaning supplies and solutions, cleaning methods, rinsing, reassembly of the device, inspection, disinfection, and sterilization.

Cross Infection↗
PubMedDate not supplied

[InterPro as a new tool for whole genome analysis. A comparative analysis of Mycobacterium tuberculosis, Bacillus subtilis and Escherichia coli as a case study].

InterPro was developed as a new integrated documentation resource for protein families, domains and functional sites to rationalize the complementary efforts of the PROSITE, PRINTS, Pfam and ProDom database projects and has applications in computational functional classification of newly determined sequences lacking biochemical characterization and in comparative genome analysis. InterPro contains over 3500 entries, with more than 1000000 hits in SWISS-PROT and TrEMBL. The database is accessible for text- and sequence-based searches at http://www.ebi.ac.uk/interpro/. InterPro was used for whole proteome analysis of the pathogenic microorganism, Mycobacterium tuberculosis, and comparison with the predicted protein coding sequences of the complete genomes of Bacillus subtilis and Escherichia coli. 64.8% of the M. tuberculosis proteins in the proteome matched InterPro entries, and these could be classified according to function. The comparison with B. subtilis and E. coli provided information on the most common protein families and domains, and the most highly represented families in each organism. InterPro thus provides a useful tool for global views of whole proteomes and their compositions.

Bacillus subtilis↗
PubMed1983

Observations on the chemical composition of Trichothecium roseum link determined by X-ray microanalysis and by laser microscopy.

In order to increase our understanding of pathogenic fungi for humans, small pieces extracted from Trichothecium roseum Link were studied, on the one hand, by X-ray microanalysis and, on the other hand, by laser microscopy. The application of these techniques in medical Mycology provides further evidence that they can be used to characterize some elements of Mendeleev's classification.

Electron Probe Microanalysis↗
PubMed1996

[Etiopathogenesis and classification of dilated cardiomyopathy].

Dilated cardiomyopathy is a diffuse disease of the myocardium, with systolic dysfunction and ventricular enlargement which is clinically expressed as heart failure and sudden death. A variety of etiologies, including myocardial diseases produced by specific local or systemic disorders can cause this syndrome. The etiological diagnosis is very difficult in the clinical setting. Because the progression of the disease is potentially reversible, discovering the cause, if possible, seems very interesting. The basic pathogenic mechanisms are not well known. The different etiopathogenic hypotheses, viral, immunological, genetic, and toxic are not incompatible and may even be complementary. Research through immunogenetical and molecular biology techniques is the key to understanding the basic mechanisms. The usefulness of genetic therapy is under investigation.

Acute Disease↗
PubMed1980

Persistence and spread of a chloramphenicol resistance-mediating plasmid in antigenic types of Escherichia coli, pathogenic for piglets.

All chloramphenicol-resistant Escherichia coli strains isolated from piglets in the State veterinary Serum Laboratory, Copenhagen, in 1974-1975 harbored plasmids of IncFII group with largely the same resistance markers. Two strains from 1978 carried plasmids with similar characters. Restriction enzyme analysis of DNA from these plasmids with restriction endonucleases EcoRI, BglII, and PstI shows that the Cm plasmids are extremely closely related; but the patterns obtained (particularly from PstI digests) enable the classification of the plasmids into groups. These bear a strong relation to time and place of isolation so that plasmids isolated on the same farm belong to the same group even when their host strains are of different antigenic types. It is concluded that these plasmids have evolved from a single plasmid.

Animals↗
PubMedDate not supplied

Photoallergic reaction. Classification and pathogenesis.

In the present article, an attempt was made to classify photoallergic reactions. Theoretically, they can be divided into four types, based on the origin of photoallergens and on the type of allergy. The photoallergen may be endogenous or exogenous in origin and photoallergic reaction may be immediate or delayed in nature. Lichen planus-like photosensitivity reaction was classified as another type of photoallergy because clinical features are distinct from the other four types. Pathogenic mechanisms were also discussed in each type of reaction, reviewing experimental evidences and speculative concepts of my own and other investigators.

Animals↗
PubMed2004

Review of statistical data about severe burn patients treated during 2001 and evidence of septic cases in Albania.

The objective of this study is to review the incidence of severe burns and the complications of burns sepsis in Albanians. The data are from clinical records of the patients hospitalised in the intensive care unit (ICU) of the Service of Burns, "Mother Teresa" University Hospital Center (UHC), Tirana, Albania during 2001. For the identification of sepsis in burned patients the classification of the American College of Chest Physicians/Society Critical Care Medicine (ACCP/SCCM) was used. All the cases were evaluated according to the clinical, diagnostic and laboratory data. The study presents some epidemiological data about the causative agent, the extent of burn, the depth of burn and the subjects injured. The study also identifies the pathogens responsible for the development of sepsis among patients. Such data was used to establish compound therapies focused on two or three antibiotics for each subject in order to treat sepsis and its possible complications. As a most important part of the treatment regime it is essential to identify patients at risk of sepsis, and to apply compound therapy with antibiotics in order to resist and treat this sepsis, which is the main cause of high mortality among our severely burned patients.

Adolescent↗
PubMed2001

Management of osteoarthritis.

PURPOSE: To review the classification, epidemiology, pathophysiology, differential diagnosis, and medical management of osteoarthritis. DATA SOURCES: Selected studies, review articles, rheumatology primers, and clinical practice guidelines. CONCLUSIONS: Osteoarthritis is the most common form of arthritis and the second most common cause of long-term disability among adults in the United States. It is a heterogeneous condition causing pathogenic changes that are presumably irreversible; it should not be considered part of "normal aging." IMPLICATIONS FOR PRACTICE: Medical management of OA includes various treatment modalities and should be based on the distribution and severity of joint involvement, as well as the presence of comorbid conditions. Treatment goals include decreasing stress on involved joints, limiting physical disability, maintaining or improving function, reducing pain, and avoiding drug toxicity.

Diagnosis, Differential↗
PubMed2001

Leptospira strains kept at the National Centre for Leptospirosis in Rome, Italy.

Since the National Centre for Leptospirosis (Department of Bacteriology and Medical Mycology, Istituto Superiore di Sanità, Rome) was established in 1956 by B. Babudieri, efforts have been devoted to identifying new Leptospira isolates and maintaining a collection of strains that today comprises 670 strains, 550 of which have been totally or partially classified, and 120 are still under study. This collection includes 23 serogroups and 156 serovars of pathogenic leptospires, and 32 serogroups and 54 serovars of saprophytic leptospires. The conventional serogroup and serovar identification, mainly based on antigenic relatedness, is tedious and time-consuming, requiring the maintenance of a comprehensive collection of serovar reference strains and the preparation of the corresponding rabbit antisera. Although considerable difficulties are encountered in the classification of leptospires at the serogroup and serovar level, this classification system is essential to obtain information on the epidemiology of leptospirosis in the different geographical areas. Serovar identification has become faster with the introduction of pulsed-field gel electrophoresis (PFGE) of large DNA fragments obtained after digestion of leptospiral DNAs with rare-cutting restriction enzymes. This technique has been successfully utilized to discriminate between closely related serovars of the Leptospira interrogans complex. We have recently used PFGE to characterize several Italian leptospiral isolates, confirming that PFGE analysis combined with microscopic agglutination test (MAT) with monoclonal and polyclonal antibodies can be used as an accurate and reliable method to compare and classify leptospires.

Animals↗
PubMed1994

[A study of nosocomial infections by the comparison of methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa].

The objective of this study was to investigate nosocomial infections by the comparison of methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa. We made a serological classification of 262 strains of Pseudomonas aeruginosa between 1983 and 1991. Group E strains were prevalent in 1987 and group F strains after 1990. Both these groups strains were resistant to several antibiotics, and were scarcely detected from the appendix contents in appendicitis that originated outside the hospital. Therefore we presumed these were nosocomial pathogens. With the countermeasures to nosocomial infections from 1987 on the isolation rate of enterotoxin type B and C MRSA strains decreased. Following this MRSA change, almost group E strains disappeared in Pseudomonas aeruginosa. Whereas type AC MRSA began to isolated abruptly from 1990, and the isolation of group F strains increased simultaneously. Type B and C strains still remained high sensitivity to minocycline. Type AC which have already gotten resistance to minocycline took the place of type B and C and prevalented. Similarly group F in Pseudomonas aeruginosa took the place of group E as soon as the former acquired resistance to carbapenem.

Cross Infection↗
PubMed2026

Performance of the IR Biotyper, Nanopore, and Illumina sequencing to discriminate Escherichia coli strains originating from poultry.

UNLABELLED: Escherichia coli is a highly diverse bacterial species that includes avian pathogenic E. coli (APEC), one of the most prevalent causative agents of disease in poultry worldwide. Rapid and accurate discrimination of E. coli strains is essential for outbreak management, antimicrobial resistance surveillance, and vaccine development. In this study, we compared the performance of Fourier Transform Infrared (FTIR) spectroscopy using the IR Biotyper system with Nanopore and Illumina whole-genome sequencing (WGS) for typing 200 E. coli isolates, originating from four poultry rearing farms in the Netherlands. From each farm, we sampled 10 one-day-old meat type rearing chicks, and from every chick, we isolated 5 E. coli strains. FTIR clustering showed strong concordance with WGS-based classifications, particularly serotyping and core-genome similarity determined by PopPUNK analysis (Adjusted Rand Index 0.75-0.92). While Nanopore and Illumina sequencing provided the highest genetic resolution, FTIR offered a faster (max 6 vs 12-28 days for 200 isolates) and more cost-effective alternative for assessing clonality. Across all methods, multiple strains were detected per farm, whereas most birds carried a single dominant E. coli strain. Our findings demonstrate that FTIR provides a reliable and scalable phenotypic method for rapid strain discrimination in E. coli, complementing WGS in diagnostic, surveillance, and epidemiological settings where speed and throughput are critical. IMPORTANCE: Escherichia coli is a major pathogen in poultry and a potential zoonotic risk for humans. Rapid and accurate discrimination of avian pathogenic E. coli (APEC) strains is critical for outbreak management, antimicrobial resistance surveillance, and the design of effective autogenous vaccines. In this study, we compared Fourier Transform Infrared (FTIR) spectroscopy with Nanopore and Illumina whole-genome sequencing for strain typing of E. coli isolates originating from poultry. The results show that FTIR provides comparable clustering accuracy to genomic approaches at a fraction of the time and costs. This work demonstrates that FTIR can serve as a practical, high-throughput alternative for routine monitoring of E. coli in veterinary diagnostics and food safety of poultry meat, enabling faster decision-making and more targeted interventions across the poultry production chain.

Animals↗
PubMed2006

Common virulence factors and genetic relationships between O18:K1:H7 Escherichia coli isolates of human and avian origin.

Extraintestinal pathogenic (ExPEC) Escherichia coli strains of serotype O18:K1:H7 are mainly responsible for neonatal meningitis and sepsis in humans and belong to a limited number of closely related clones. The same serotype is also frequently isolated from the extraintestinal lesions of colibacillosis in poultry, but it is not well known to what extent human and avian strains of this particular serotype are related. Twenty-two ExPEC isolates of human origin and 33 isolates of avian origin were compared on the basis of their virulence determinants, lethality for chicks, pulsed-field gel electrophoresis (PFGE) patterns, and classification in the main phylogenetic groups. Both avian and human isolates were lethal for chicks and harbored similar virulence genotypes. A major virulence pattern, identified in 75% of the isolates, was characterized by the presence of F1 variant fimbriae; S fimbriae; IbeA; the aerobactin system; and genomic fragments A9, A12, D1, D7, D10, and D11 and by the absence of P fimbriae, F1C fimbriae, Afa adhesin, and CNF1. All but one of the avian and human isolates also belonged to major phylogenetic group B2. However, various subclonal populations could be distinguished by PFGE in relation to animal species and geographical origin. These results demonstrate that very closely related clones can be recovered from extraintestinal infections in humans and chickens and suggest that avian pathogenic E. coli isolates of serotype O18:K1:H7 are potential human pathogens.

Animals↗
PubMed1990

Characterization and reclassification of yeasts used for biological control of postharvest diseases of fruits and vegetables.

In previous studies workers have shown that three yeast strains (strains US-7, 82, and 101) have biological control activity against various postharvest fungal pathogens of fruits and vegetables, including Penicillium rots of apples and citrus and Botrytis rot of apples. In these reports the researchers have described these strains as Debaryomyces hansenii (anamorph, Candida famata) or Candida sp. strains. In this study we performed additional physiological, DNA reassociation, and mannan characterization tests that clearly established a new taxonomic classification for these strains, Candida guilliermondii. We also propose amendment of the physiological test profile in the taxonomic description of C. guilliermondii.

Journal Article↗
PubMed2026

Genetic diversity and recombination of NA-PRRSV field strains in Vietnam: Implications for vaccine efficacy.

Porcine reproductive and respiratory syndrome (PRRS) causes severe reproductive losses in pregnant sows and piglets, resulting in substantial economic impact on the swine industry worldwide. However, due to the significant genetic diversity and rapid evolutionary changes of the pathogen, continuous surveillance and detailed genetic analysis of circulating strains are essential. The current study aimed to evaluate the genetic diversity of the hypervariable (HV) region of non-structural protein 2 (nsp2) among North American PRRSV strains isolated from swine farms in Vietnam. Phylogenetic analysis and multiple sequence alignment were conducted to determine subtype classification and assess genetic variability. A total of 48 field isolates were obtained, of which 12.5% belonged to classical NA-PRRSV, 16.6% to NADC30-like and 70.9% to HP-PRRSV, primarily distributed across sublineages 1.4, 5.1, 8.7 and 8.9. Amino acid comparisons found multiple insertions, deletions and substitutions at various positions within the hypervariable region of nsp2. The study revealed substantial genetic variation in the HV region of nsp2 among NA-PRRSV field strains, largely associated with recombination and immune escape. These findings highlight epidemiological risks to vaccine efficacy and underscore the need for continuous molecular surveillance to support effective PRRSV control in Vietnam.

PRRSV↗
PubMed2005

Genetic characterization of the lobster pathogen Aerococcus viridans var. homari by 16S rRNA gene sequence and RAPD.

A combination of 16S rRNA sequencing and random amplified polymorphic DNA (RAPD) analysis was used to evaluate the genetic diversity within Aerococcus viridans var. homari, the causative agent of gaffkemia in lobsters. A collection of 7 A. viridans var. homari strains and 2 avirulent A. viridans-like cocci isolated from homarid lobsters harvested from different regions on the Atlantic Coast of North America were analyzed. The isolates are separated geographically and temporally between the years 1947 and 2000. Sequencing of 16S rRNA genes confirmed the inclusion of all 9 isolates in the monophyletic A. viridans clade (99.8 to 100% similarity). RAPD analysis revealed that the 9 A. viridans var. homari isolates could be separated into 2 distinct subtypes. Subtype 1 included the 7 pathogenic lobster isolates and constituted a homogeneous group regardless of their geographical, temporal or virulence differences. Subtype 2 contained the 2 avirulent A. viridans-like cocci that had distinct RAPD patterns and clustered separately with the non-marine A. viridans. RAPD analysis represented a useful method for determining molecular subtyping for the intraspecific classification and epidemiological investigations of A. viridans var. homari.

Animals↗
PubMed1996

[Respiratory infections--pathogenesis of acute and chronic infections].

Respiratory infections in Japan have rapidly changed, because pathogenesis has also changed by the increase of compromised hosts and aged people with the development of chemotherapeutic agents and another medical progresses. Various respiratory infections have been accumulated in our clinical department and clinical investigations were done for these diseases during almost 20 years. Firstly, pneumonias in adult T cell leukemia have been very severe and these diseases have occurred with load from pathogenic orophayngeal bacteria to lower respiratory airway. With another clinical studies, these pathogenesis which firstly pathogenic bacteria attach to orophayngeal epithelial cells and would move to lower respiratory airway to infect were given very clear evidences especially for Branhamella and Pneumococcus infections with chronic respiratory infections. The exact clearance of pathogenic orophayngeal bacteria using povidon iode solution was very useful for prevention of these acute or chronic respiratory infections. Although acute bronchitis is very popular, the secondary bacterial pathogens remained to be unknown, in the world. We showed that H. influenzae, S.pneumoniae and B.catarrhalis were common major pathogens as the secondary invading bacteria of acute bronchitis in Japan, Thailand and Bangladesh. Recently, the pathogenesis of severe chronic respiratory infections such as diffuse panbronchiolitis is focused after the development of erythromycin therapy. We gave some evidences of macrolides effectiveness which these drugs inhibited IL-8 production. We described the importance of inflammatory cell classification in sputa or bronchial secretions for deep understanding of inflammatory situation in broncho-bronchiolar airway.(ABSTRACT TRUNCATED)

Acute Disease↗