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Prevalence of Serpulina species in relation to diarrhea and feed medication in pig-rearing herds in Sweden.

OBJECTIVE: To determine prevalence of various pheno- and genotypes of Serpulina sp in young pigs in relation to diarrhea and feed medication in Swedish pig-rearing herds. DESIGN: Isolation of spirochetes. Phenotypical and genotypical classification. SAMPLE POPULATION: Young pigs (n = 358) in 19 pigrearing herds. PROCEDURE: Serpulina isolates were classified according to a biochemical scheme based on hemolysis, indole production, hippurate hydrolysis, and alpha-galactosidase, alpha-glucosidase, and beta-glucosidase activities. The 16S rRNA sequences for 10 of the field strains and 2 type strains of Serpulina spp were aligned and compared. Minimum inhibitory concentrations of olaquindox for 9 of the strains were determined. RESULTS: Weakly beta-hemolytic intestinal spirochetes (WBHIS) were isolated from 17 of the herds and 65% of the samples. More than 1 phenotype of WBHIS was found in 12 of the 19 herds. S hyodysenteriae was not isolated in any of the herds. Hippurate-positive WBHIS were isolated in 6 of 7 herds affected by diarrhea, but in only 1 of 8 herds without diarrhea. Hippurate-positive strains were closely related to the pathogenic strain P43 if judged from sequence comparisons. Strains with the same biochemical profile isolated within a herd had identical sequences, but when isolated from different herds, sequence differences were observed. The prevalence of WBHIS was reduced in herds medicated with olaquindox. Investigated field strains had minimum inhibitory concentration values < or = 1 microgram/ml for olaquindox. CONCLUSION: The presence of WBHIS, with the ability to hydrolyze hippurate, was related to diarrhea in pig herds. CLINICAL RELEVANCE: Potentially pathogenic WBHIS can be distinguished from nonpathogenic strains by the hippurate hydrolysis test.

Animal Feed↗

Toys in a pediatric hospital: are they a bacterial source?

BACKGROUND: In children's hospitals, children are commonly provided with toys. Measures to guarantee the safety of these toys are usually not taken. This study was conducted to determine whether toys were contaminated with potentially pathogenic bacteria when they arrived in the hospital, and whether they were contaminated in the hospital. METHODS: The study was conducted during a 3-month period. Children who were hospitalized for at least 3 days were chosen as study subjects. Once these children were identified, cultures from their toys were obtained within the first 48 hours of admission. After this first culture, toys were cleaned with 4% chlorhexidine and water and were immediately re-cultured. Following cultures were collected on days 5 to 7, 10 to 15, and every week thereafter until the owner-patient was discharged. Specimens were collected in a standardized manner with moistened swabs and placed in transport media. They were later inoculated onto trypticase soy agar with 5% sheep blood and brain heart infusion agar, incubated at 37 degrees C for 48 hours and examined for colony growth at 24 to 48 hours. RESULTS: Seventy children's toys were included in this study. Patients' median age was 26 months (range: 1 day to 9 years). Respiratory infections (43%) and diarrhea (26%) were the most common causes of hospitalization. Fifty-three (76%) toys were made of plastic, 8 (11%) metallic, and 9 (13%) other materials. Twenty-nine (41%) were brought from home, 38 (55%) were purchased from roving vendors, and 3 (4%) were purchased from toy stores. All first cultures were positive for at least 1 pathogenic microorganism: 55 (78%) coagulase-negative Staphylococcus (CNS); 26 (37%) Bacillus spp; 13 (18%) Staphylococcus aureus; 8 (11%) alpha-hemolytic Streptococcus; 5 (9%), Pseudomonas spp; 2 (3%) Stenotrophomonas maltophilia, and 6 (11%) other gram-negative organisms. After toys were cleaned, subsequent cultures showed significant decreases in bacterial growth rates (P <.05). Because some patients were discharged, additional cultures were obtained for only 31 toys. CONCLUSIONS: Toys entering a hospital can be contaminated with potentially dangerous bacteria and may provide unnecessary risks for nosocomial infection. Effective measures must be implemented to prevent the spread of infections via toys.

Bacteria↗

Pathogenic profiles and molecular signatures of antinuclear autoantibodies rescued from NZM2410 lupus mice.

Two outstanding questions concerning antinuclear antibodies (ANAs) in lupus involve their pathogenic potential and their molecular signatures. To address these questions, a panel of 56 antinuclear and 47 nonnuclear binding monoclonal antibodies was rescued from four seropositive NZM2410 lupus mice. The monoclonals varied in their reactivity to nucleosomes, ssDNA, dsDNA, and glomerular substrate. A large fraction of the antibodies demonstrated apparent polyreactivity (to DNA, histones, and glomerular antigens) due to bound, DNase-1 sensitive nuclear antigenic bridges. Although nephrophilic immunoglobulin (Ig) M and IgG antibodies were the most pathogenic, the dsDNA-binding antibodies were modestly so; in contrast, antinucleosome antibodies were clearly not pathogenic. Compared with the nonnuclear antigen-binding monoclonal antibodies rescued from the same mice, ANAs exhibited increased utilization of VH5/7183 genes and highly cationic heavy chain (HC) CDR3 regions. Most intriguingly, the CDR3 regions of the ANAs exhibited alternating arginine/lysine peaks at H96, H98, and H100, with neutral troughs at H95, H97, and H99. To summarize, glomerular-binding anti-dsDNA antibodies appear to be the most pathogenic variety of lupus autoantibodies. The presence of an alternating charge pattern in their HC CDR3 regions appears to be a prominent hallmark of ANAs.

Amino Acid Sequence↗

Localization and functions of SP-A and SP-D at mucosal surfaces.

Pulmonary surfactant protein A (SP-A) and D (SP-D), members of the collectin family, are implicated in innate host defense of the lung. Collectins consist of a collagen-like domain and a carbohydrate recognition domain. SP-A and SP-D recognize and interact with glycoconjugates on the surface of microorganisms. They protect the lung by interacting with a wide variety of potential pathogens, including viruses, bacteria, and fungi. This may result in enhanced killing and/or clearance by phagocytes. Although most extensively studied in the lung, both SP-A and SP-D, or proteins closely resembling SP-A and SP-D, are found in a number of other sites in the body and therefore may play a protective role at other sites than the lung. SP-A and SP-D protein and/or mRNA have been detected at various sites of the body: the respiratory tract, the gastrointestinal tract, the middle ear, and in the peritoneal cavity. The presence of SP-A and SP-D at these mucosal surfaces, in close contact with numerous potentially harmful microorganisms, supports a role for these "lung"-collectins in innate mucosal defense. SP-A and SP-D may be important molecules in a threefold innate defense, particularly in the neonatal period between maternally acquired immunity and a fully developed adaptive immune system; the time interval between first exposure to a pathogen and generation of specific antibodies; and states of impaired immune function.

Animals↗

The TIGR gene, pathogenic mechanisms, and other recent advances in glaucoma genetics.

Important advances have been made within the past year in the area of glaucoma genetics, including the identification of the TIGR gene for adult as well as juvenile GLC1A glaucoma, a P450 gene for GLC3A congenital glaucoma, and a bicoidhomeobox transcription factor gene RIEG for developmental glaucoma. The cloning of TIGR as a candidate gene for glaucoma is based on its distinctive induction in human trabecular meshwork cells and tissues, its induction profile, and the expressed molecule's putative biologic properties. Results from several laboratories showing defects in the olfactomedin homology domain of the TIGR gene have generated particular interest concerning potential pathogenic mechanisms. Recent progress in glaucoma genetics has also included the identification of new loci in familial adult open-angle glaucoma, the identification of a locus associated with pigment dispersion syndrome, and the collection of new families for linkage analyses and clinical assessments. Taken together, these findings offer future prospects for improving diagnostic criteria, for understanding disease etiologies, and for developing improved therapeutic strategies.

Adolescent↗

Prospective randomized comparison of imipenem/cilastatin and cefotaxime for treatment of lung, soft tissue, and renal infections.

Thirty-one moderately or severely ill hospitalized patients with proved (25 patients) or suspected (six) bacterial infections were randomly allocated to receive imipenem/cilastatin (16) or cefotaxime (15). The median age, sex, duration of therapy, underlying disease, and types of infection were similar in both groups. Nineteen patients with pneumonia, eight with soft tissue infection, and four with acute pyelonephritis were included. The pathogens isolated included Escherichia coli (six), Streptococcus pneumoniae (five), Streptococcus pyogenes (five), Haemophilus species (four), Proteus species (three), Staphylococcus aureus (three), and Serratia marcescens (two). In the imipenem/cilastatin group, 13 patients were cured of their infections and three showed improvement. In the cefotaxime group, nine were cured, three showed improvement, and three showed no improvement. Nine patients treated with imipenem/cilastatin developed phlebitis, as compared with eight treated with cefotaxime. One patient treated with cefotaxime developed diarrhea. During therapy, potential pathogens were isolated from four patients in the imipenem/cilastatin group (Candida species [two] and Pseudomonas maltophilia [two]), as compared with eight in the cefotaxime group (enterococci [two], Pseudomonas aeruginosa [two], Candida species [two], Acinetobacter anitratus [one], and Pseudomonas fluorescens [one]). There were no recognized superinfections.

Adult↗

Selection of potential probiotic lactobacilli from pig feces to be used as additives in pelleted feeding.

Thirty-five isolates from pig feces were identified as Lactobacillus reuteri (12 strains), Lactobacillus mucosae (7), Lactobacillus plantarum (6), Lactobacillus kitasatonis (3), Lactobacillus rossiae (2), Lactobacillus ultunensis (2), Lactobacillus crispatus (2), and Lactobacillus intestinalis (1) by partial sequence analysis of the 16S rRNA. All isolates were detected at 8-9 log CFU g(-1). Preliminarily, strains were selected based on resistance to heat treatments (ca. 70 degrees C for 10 s). The decrease in viability for some L. reuteri, L. mucosae, L. plantarum, L. kitasatonis, and L. rossiae strains was lower than 1 log cycle. Selected strains were further characterized for acid and bile salt resistance, and antibacterial activity. Except for L. kitasatonis, tolerance to simulated gastric and intestinal conditions was enhanced for all strains by addition of reconstituted skimmed milk. Antibacterial activity was found against Gram-positive and -negative potential pathogens. L. reuteri 8.1, 3S7, 6.2, and 1.2, L. mucosae 1.1R, L. plantarum 4.1, and L. rossiae 4.4 were freeze-dried and mixed (1%, w/w) into pig feed before pelleting. After pelleting, pig feed contained 10-9 log CFU kg(-1) of lactobacilli. L. plantarum 4.1, and L. reuteri 3S7 were selected based on their bile salt resistance, pH tolerance, antimicrobial activity and heat resistance. The findings in this study provide a strong basis for exploring the potential of porcine lactobacilli isolates to be used in pelleted feeding as probiotic additives.

Animal Feed↗

Chlamydia pneumoniae infection and acute exacerbation of chronic obstructive pulmonary disease (COPD).

The objective of the study was to investigate the possible association of Chlamydia pneumoniae (Cpn) in acute exacerbations of chronic obstructive pulmonary disease (COPD) patients. Thirty-eight acutely exacerbated COPD patients and 17 healthy smokers were enrolled in the study, as the study and control groups respectively. Nasopharyngeal swabs and paired serum samples for antibody testing of Cpn (microimmunofluorescence--MIF) were obtained from all subjects. Sputum cultures of COPD patients were also performed. No pathogenic bacteria were isolated from nasopharyngeal swabs in any subject. Serologic evidence of recent Cpn infection was observed in 13 (34%) COPD patients and in one (5%) control subject. The prevalence of Cpn IgG and IgM antibodies representing acute infection were significantly higher in COPD patients than in control subjects (P < 0.05 and P < 0.01 respectively). Prevalence of IgA antibodies and IgG pre-existing antibodies did not show any difference (P > 0.05). Microbiologic culture of the sputa yielded potentially pathogenic micro-organisms in 23 of 38 (60%) COPD patients. Alpha-haemolytic streptococcus (35%), Niesseria spp. (31%) and Candida spp. (9.5%) were most prominent micro-organisms in positive cultures. Although a high prevalence of IgG antibodies against Cpn was detected, it was the sole causative agent in only four (10%) patients. We conclude that a remarkable number of COPD patients (34%) are acutely infected with Cpn and it may either be the sole causative agent or frequently a co-agent in acute exacerbations.

Acute Disease↗

Mycoses caused by Candida lusitaniae.

Candida lusitaniae, a fungus with a low incidence of infection in immunocompetent people, is emerging as an opportunistic pathogen in immunocompromised hosts. This yeast is generally resistant to amphotericin B and may present therapeutic difficulties. C. lusitaniae may be misidentified as one of several other fungal species, including Candida tropicalis, Candida parapsilosis, and even Saccharomyces cerevisiae. As judged by in vitro antifungal susceptibility testing, minimal inhibitory concentrations of antifungal agents other than amphotericin B are achievable, but fungicidal levels are not. When encountered in blood or other body sites, C. lusitaniae should be carefully considered as a potential pathogen.

Aged↗

Occurrence, diversity, and pathogenicity of halophilic Vibrio spp. and non-O1 Vibrio cholerae from estuarine waters along the Italian Adriatic coast.

The occurrence, diversity, and pathogenicity of Vibrio spp. were investigated in two estuaries along the Italian Adriatic coast. Vibrio alginolyticus was the predominant species, followed by Vibrio parahaemolyticus, non-O1 Vibrio cholerae, and Vibrio vulnificus. By using a biochemical fingerprinting method, all isolates were grouped into nine phenotypes with similarity levels of 75 to 97.5%. The production of toxins capable of causing cytoskeleton-dependent changes was detected in a large number of Vibrio strains. These findings indicate a significant presence of potentially pathogenic Vibrio strains along the Adriatic coast.

Animals↗

Biliary liver flukes (Opisthorchiasis and Clonorchiasis) in immigrants in the United States: often subtle and diagnosed years after arrival.

BACKGROUND: Biliary liver flukes are extremely common parasites in some regions of the world where consumption of raw fresh-water fish is a cultural practice. Clonorchis sinensis and Opisthorchis spp. are the major biliary liver flukes associated with human disease. Some of these parasites are highly associated with cholangiocarcinoma. It was noted that several cases presenting at our center had been in the US for prolonged periods. This prompted us to retrospectively review cases of liver fluke infection diagnosed at our facility. METHODS: All cases of biliary liver fluke infection over a 6-year period were retrospectively investigated at a clinic serving international patients, to determine the prevalence and risk factors for infection in a nonendemic area. Cases were identified through review of stool ova and parasite (O&P) records maintained at Regions Hospital/HealthPartners microbiology laboratory. All O&P samples positive for Opisthorchis spp. or Clonorchis sinensis were included in the review. RESULTS: Seventeen cases were identified during the study period. Our center performed approximately 1,800 stool O&P examinations per year on approximately 1,100 individuals per year during the study period. Biliary liver flukes were uncommon, accounting for 1.3% of individuals infected with organisms considered to be potentially pathogenic. Infections were predominantly found in migrants from Laos, Cambodia and Thailand. Cases were also identified in migrants from the former Soviet Union and South America. It is of note that 25% of patients were detected after 5 years of residence in the US. Often, the only clinical clue to infection was a mild absolute eosinophilia (500 to 1000 microL). CONCLUSIONS: Although biliary liver fluke is an infrequent cause of infection in immigrants to the US, because of the potential long-term consequences of chronic infection, educational information highlighting routes of infection and the fact that asymptomatic infection is common and may eventually lead to cancer should be aimed at high-risk community members and those who have been visiting friends and relatives in endemic areas.

Adolescent↗

Site-related airborne biological hazard and seasonal variations in two wastewater treatment plants.

Results of a study conducted to assess the degree of airborne bacterial contamination generated by two wastewater treatment plants (WWTP) with different treatment systems and evaluate the dispersion of potential pathogens, have been described. Aerosols samples were collected in summer and winter with an agar impact sampler from several plant sites. External upwind and downwind controls were also examined. Total colony-forming counts of mesophilic and thermophilic bacteria, actinomycetes and streptomycetes, Gram-negatives, coliforms and sulfite-reducers were determined. Selective media were used in order to detect pathogenic bacteria. The lowest concentrations of mesophilic and thermophilic bacteria were 8 and 28 CFU/m(3) in plants A and B respectively, the highest >40,000 CFU/m(3) in both plants. Strains of Escherichia coli, Clostridium perfringens, Staphylococcus aureus and Enterococcus spp. were isolated in some sites of the two plants. Salmonella spp., Yersinia enterocolitica and Legionella spp. were never detected. The activities involving nebulization and mechanical aeration of wastewaters and the sewage inflows have proved to be of greatest potential risk. In both plants, we found a statistically significant dependence of bacterial contamination on the season for many of the analyzed parameters but a clear seasonal trend could not be observed.

Air↗

Comparison of the genome of the oral pathogen Treponema denticola with other spirochete genomes.

We present the complete 2,843,201-bp genome sequence of Treponema denticola (ATCC 35405) an oral spirochete associated with periodontal disease. Analysis of the T. denticola genome reveals factors mediating coaggregation, cell signaling, stress protection, and other competitive and cooperative measures, consistent with its pathogenic nature and lifestyle within the mixed-species environment of subgingival dental plaque. Comparisons with previously sequenced spirochete genomes revealed specific factors contributing to differences and similarities in spirochete physiology as well as pathogenic potential. The T. denticola genome is considerably larger in size than the genome of the related syphilis-causing spirochete Treponema pallidum. The differences in gene content appear to be attributable to a combination of three phenomena: genome reduction, lineage-specific expansions, and horizontal gene transfer. Genes lost due to reductive evolution appear to be largely involved in metabolism and transport, whereas some of the genes that have arisen due to lineage-specific expansions are implicated in various pathogenic interactions, and genes acquired via horizontal gene transfer are largely phage-related or of unknown function.

ATP-Binding Cassette Transporters↗

Prediction of parasite infection dynamics in primate metapopulations based on attributes of forest fragmentation.

Although the effects of forest fragmentation on species and ecological processes have been the focus of considerable research in conservation biology, our capacity to predict how processes will be altered and which taxonomic or functional groups will be most affected by fragmentation is still poor. This problem is exacerbated by inherent temporal and spatial variability in fragment attributes. To improve our understanding of this interplay, we examined how various fragment attributes affect one potentially important ecological process, parasite infection dynamics, and considered how changes in this process affect host metapopulations. From August 1999 to July 2003 we surveyed red colobus (Piliocolobus tephrosceles) metapopulations inhabiting nine fragments (1.2 to 8.7 ha) in western Uganda to determine the prevalence and richness of strongyle and rhabditoid nematodes, a group of potentially pathogenic gastrointestinal parasites. We used noninvasive fecal flotation and sedimentation (n = 536) to detect parasite eggs, cysts, and larvae in colobus fecal samples. To obtain an index of infection risk, we determined environmental contamination with Oesophagostomum sp., a representative strongyle nematode, in canopy (n = 30) and ground vegetation plots (n = 30). Concurrently, physical (i.e., size, location, and topography) and biological (i.e., tree diversity, tree density, stump density, and colobine density) attributes were quantified for each fragment. Interfragment comparisons of nine potential factors demonstrated that an index of degradation and human presence (tree stump density) strongly influenced the prevalence of parasitic nematodes. Infection risk was also higher in the fragment with the highest stump density than in the fragment with the lowest stump density. These results demonstrate that host-parasite dynamics can be altered in complex ways by forest fragmentation and that intensity of extraction (e.g., stump density) best explains these changes.

Animals↗

Molecular changes in Entamoeba histolytica in response to bacteria.

Entamoeba histolytica, the protozoan parasite, is the causative agent of amoebiasis. The degree of virulence, as inferred from invasiveness, of potentially pathogenic strains may be regulated by both host and parasite factors that determine the gut environment. One such factor that plays an important role is the bacterial flora in the gut. Previous studies have clearly shown that bacterial flora is an important determinant of virulence in E. histolytica. However, the exact nature of changes induced in E. histolytica in response to bacteria and their role in virulence is not clear. In this study the levels of a number of molecules potentially important in virulence mechanisms were determined in E. histolytica cells grown with and without normal human bacterial flora, using enzyme-linked immunosorbent assay. Significant changes were observed only after the E. histolytica cells had been adapted to grow with bacterial flora for a number of generations, and not in short term culture.

Animals↗

Genomic analysis reveals that Pseudomonas aeruginosa virulence is combinatorial.

BACKGROUND: Pseudomonas aeruginosa is a ubiquitous environmental bacterium and an important opportunistic human pathogen. Generally, the acquisition of genes in the form of pathogenicity islands distinguishes pathogenic isolates from nonpathogens. We therefore sequenced a highly virulent strain of P. aeruginosa, PA14, and compared it with a previously sequenced (and less pathogenic) strain, PAO1, to identify novel virulence genes. RESULTS: The PA14 and PAO1 genomes are remarkably similar, although PA14 has a slightly larger genome (6.5 megabses [Mb]) than does PAO1 (6.3 Mb). We identified 58 PA14 gene clusters that are absent in PAO1 to determine which of these genes, if any, contribute to its enhanced virulence in a Caenorhabditis elegans pathogenicity model. First, we tested 18 additional diverse strains in the C. elegans model and observed a wide range of pathogenic potential; however, genotyping these strains using a custom microarray showed that the presence of PA14 genes that are absent in PAO1 did not correlate with the virulence of these strains. Second, we utilized a full-genome nonredundant mutant library of PA14 to identify five genes (absent in PAO1) required for C. elegans killing. Surprisingly, although these five genes are present in many other P. aeruginosa strains, they do not correlate with virulence in C. elegans. CONCLUSION: Genes required for pathogenicity in one strain of P. aeruginosa are neither required for nor predictive of virulence in other strains. We therefore propose that virulence in this organism is both multifactorial and combinatorial, the result of a pool of pathogenicity-related genes that interact in various combinations in different genetic backgrounds.

Base Sequence↗

Exploring the c.406&#xa0;C&#x2009;>&#x2009;T variant in TNNI3 gene: pathogenic insights into restrictive cardiomyopathy.

BACKGROUND: Restrictive cardiomyopathy (RCM) is a rare cardiac disorder characterized by diastolic dysfunction and myocardial stiffness, frequently associated with genetic variants. We aimed to explore the genetic basis of RCM in a diagnosed patient through comprehensive genetic analysis. METHODS: Whole exome sequencing (WES) was conducted on the proband, followed by Sanger sequencing for variant confirmation and familial segregation analysis. In silico tools and structural protein modeling were employed to assess the functional impact of the identified variant. RESULTS: The c.406&#xa0;C&#x2009;>&#x2009;T variant, classified as likely pathogenic, results in a truncated TNNI3 protein. Bioinformatics analysis highlighted significant structural disruptions, likely impairing sarcomere function. The patient presented with growth retardation, progressive dyspnea, and echocardiographic findings consistent with RCM. Both parents were heterozygous carriers, supporting an autosomal recessive inheritance pattern. The homozygosity of the novel variant identified in this study is a critical factor in the genotype-phenotype correlation observed in this case. CONCLUSION: This study identified the novel c.406&#xa0;C&#x2009;>&#x2009;T variant in TNNI3 as a potential pathogenic driver of RCM, emphasizing the critical role of genetic evaluations in early diagnosis and management of inherited cardiomyopathies. Further studies are warranted to explore therapeutic interventions targeting TNNI3-related pathologies.

Humans↗

A study of the microbial quality and organoleptic properties of ophthalmic preparations obtained from traditional medical practitioners in South Western Nigeria.

Twenty eight samples of traditional ophthalmic preparations were obtained from various traditional medical practitioners in the South Western states of Nigeria over a one-year period. They were examined for sterility, clarity, presence of particulate contamination and pH. All of them were found to be contaminated with bacteria to the order of 2.00 x 10(6) to 1.60 x 10(11) colony forming units/ml, with Pseudomonas species and other potential pathogens such as Staphylococcus aureus, Yersinia enterocolita, Micrococcus varians and others being isolated from these preparations. A rotifer Rotaria rotatoria, at the adult stage, was also isolated from one sample, this being an indication of gross faecal contamination. All the samples were also found to contain significant particulate contamination and pH values encountered varied over the range of 2.5-9.2. None of the samples was found to comply with official specifications and all of them may therefore be regarded as being potentially dangerous to the users.

Animals↗