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At least 19 recordsLinked to original sources
PubMed1977

Enteric pathogens in infants and children in Shiraz, Iran: A study of their incidences and infectious drug resistance.

Gastroenteritis is a serious problem among young children in Shiraz Iran and often requires antibiotic therapy as it is commonly superimposed on other debilitating clinical conditions. Stool specimens from over four hundred cases of gastroenteritis among children up to six years of age were examined for the presence of bacterial pathogens and the pattern of drug sensitivity for each pathogenic genus was determined. The presence of infectious drug resistance factors among these isolates was also established.

Ampicillin↗
PubMed1978

[Studies on the viability of pathogenic amebae of the genus Naegleria in water of different sources (author's transl)].

Water specimens taken from the public water supply (A), a swimming-pool (B), and an inland lake (C) were infected with pathogenic amebae of the genus Naegleria (strain TY/Richmond). The specimens were stored at various temperatures for different periods. The water was then filtered and examined for naegleriae by animal inoculation. The results summarized in table 1 indicate that pathogenic naegleriae are viable at least for some weeks in warm tap and natural waters. Water from indoor swimming-pools however, may be a less suitable medium for the viability of pathogenic naegleriae.

Amoeba↗
PubMedDate not supplied

[Ecological and epidemiological relationships between Sporothrix schenckii, a fungus pathogenic for man and the Ceratocystis genus].

Sporothrix schenckii is a pathogenic fungus for man and animal. Its perfect form is not yet known. Many studies have been made to compare this fungus to ascomycetes belonging to the genus Ceratocystis. This paper summarizes some important data about the ecology and the epidemiology of the fungal complex Sporothrix-Ceratocystis. Previous results obtained by several groups of workers are strongly in favor of a relationship between the two genera. The epidemiological studies carried out in different areas have shown that Sporothrix schenckii and Ceratocystis stenoceras are frequently isolated from the same fragments of plants such as pine or eucalyptus. According to the time and areas, it appears that there is or there is not a relation between the presence of the fungus on the plants or in the soil and the disease. The former case is well illustrated by the epidemic of the Transvaal between 1940 and 1944. Sporothrix schenckii has been found to be present either in endemic areas like Guatemala (around the Ayarza Lake) or in Alsace, or in Corse where no case has been reported for a long time. In France, except for the curious epidemic observed between the years 1903 and 1912, no or very rare cases have been observed although Sporothrix schenckii is abundant in the soil and injuries with contaminated materials are probably extremely frequent. The presence or even the abundance of the fungus in nature is not enough to explain the development of the disease. Some not well known factors are necessary. So as for all disease, the immunological reaction of the host is important and the defects of these mechanisms must be suspected.

Ascomycota↗
PubMed1979

Pathogenic species of the genus Haemophilus and Streptococcus pneumoniae produce immunoglobulin A1 protease.

Thirty-seven strains of the genus Haemophilus and five strains of Streptococcus pneumoniae were examined for their ability to produce extracellular enzyme that cleaves immunoglobulin molecules. All strains of H. influenzae, H. aegyptius, and S. pneumoniae elaborated enzyme that selectively cleaved human immunoglobulin A1 (IgA1) myeloma proteins but was inactive against a variety of other proteins including human IgA2, IgG, and IgM, porcine and bovine secretory IgA, human and bovine serum albumins, and ovalbumin. Although susceptible, human secretory IgA remained largely undigested. Two strains of H. pleuropneumoniae isolated from fatally infected pigs cleaved porcine secretory IgA, but had no effect on human IgA proteins. None of 16 strains that belonged to nonpathogenic Haemophilus species produced IgA protease. Analyses of the cleavage products of human IgA1 and secretory IgA proteins by immunochemical methods, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and analytical ultracentrifugation revealed that Fab and Fc fragments were produced. Since the production of IgA1 protease by Neisseria meningitidis has been reported previously, our finding that H. influenzae and S. pneumoniae produce an IgA1 protease indicates that this is a property of all three major etiological agents of bacterial meningitis. This suggests that IgA1 protease production may be an important factor in the pathogenesis of this disease.

Haemophilus↗
PubMed2026

Characterization of the oral microbiota and antimicrobial resistance genes in shelter dogs in Japan.

Companion animals can serve as reservoirs of antimicrobial resistance genes and zoonotic microorganisms, yet information on shelter dogs remains limited. This study characterized the oral microbiota and screened for antimicrobial resistance genes in shelter dogs in Japan. Oral swabs were collected from 81 dogs, microbial genomic DNA was extracted, bacterial communities were profiled by 16S rRNA gene amplicon sequencing, and antimicrobial resistance genes were screened by PCR. We detected genes conferring resistance to several antimicrobial classes, including β-lactams, tetracyclines, macrolide-lincosamide-streptogramin B, phenicols, and sulfonamides. cfxA was detected in all 81 samples, followed by sul1 (66/81), tet(M) and sul2 (65/81), floR (39/81), mecA (17/81), and erm(B) (15/81). We identified potentially pathogenic genera including Capnocytophaga, Pasteurella, Fusobacterium, Campylobacter and Corynebacterium. Microbiome analysis revealed that at the phylum level, Pseudomonadota and Bacteroidota were the most dominant, while Porphyromonas, Frederiksenia and Moraxella were the most prevalent genera. Our findings highlight that (i) the oral microbiota of shelter dogs broadly resembles that reported in companion dogs and (ii) shelter dogs represent an overlooked reservoir of clinically relevant antimicrobial resistance genes and potentially zoonotic bacteria. Therefore, it is necessary to include shelter animals in antimicrobial resistance surveillance programs to capture any potential gaps in the antimicrobial resistance prevalence in companion animals and prevent dissemination of resistant bacteria to humans following adoption of shelter dogs and cats.

antimicrobial resistance gene↗
PubMed1975

Virulence of genus Staphylococcus. III. Studies on the pathogenicity to mice.

Six representative strains of staphylococci were selected on the basis of DNase activity and inoculated into the mice to study the correlation of the presence of this enzyme to the virulence of the staphylococci. Two strains of staphylococci among them produced DNase but not the free coagulase, and one of these two strains had an obvious virulence against the mice. The results of experiments suggest that there are at least certain strains which may be designated as Staphylococcus aureus among these DNase-producing staphylococci producing no free coagulase. This is an additional evidence that this enzyme activity should be adopted as a criterion to distinguish from the other S. aureus which has lost the free coagulase activity. In this sense, the staphylococci producing neither free coagulase nor DNase are after all Staphylococcus epidermidis, regardless of their ability to ferment mannitol or not.

Animals↗
PubMed1978

IgA protease production as a characteristic distinguishing pathogenic from harmless neisseriaceae.

IgA proteases are extracellular enzymes of bacteria that have human immunoglobulin A of the IgA1 subclass as their only known substrate. The identification of this enzyme in neisseria prompted us to determine whether IgA protease production correlates with pathogenicity within this genus. Multiple clinical isolates of Neisseria gonorrhoeae, N. meningitidis and eight species of non-pathogenic neisseria that commonly colonize the normal human nasopharynx were examined for IgA protease activity. All N. gonorrhoeae and N. meningitidis strains were enzyme positive; all non-pathogenic strains were negative. Among meningococci, the enzyme occurred in strains carried harmlessly in the nasopharynx as well as those isolated from systemic infections. Because mucosal immune defense is largely mediated by antibodies of the IgA isotype, the finding that IgA protease activity is linked specifically to the pathogenic neisseria suggests that the enzyme may be involved in the pathogenesis of neisserial infection.

Gonorrhea↗
PubMedDate not supplied

[Dissociative phases and pathogenicity of different species of the Bacillus genus].

The previously postulated hypothesis, according to which different species of the genus Bacillus show strictly similar morphological and biological properties when the same variants are considered, has been confirmed by the present research. The "S" (smooth) variants of the five studied species (B. anthracis, B. subtilis, B. cereus, B. megaterium, B. mesentericus) are all lethal, at the experimented dose, for mice, whereas the "R" (rough, "star-shaped" colonies) variant of the same strains of the same species are all not pathogenic for the same animals. Likewise the "S" variants of three species tested in guinea pigs showed to be pathogenic; particularly B. anthracis and B. subtilis were lethal, whereas B. cereus caused a black eschar like that one described in the cutaneous anthrax. The "RS" variant ("medusae head" surface colonies) is not pathogenic for mice and guinea pigs (even B. anthracis) if the tested strains are cultivated for years in ordinary solid nutrient media; the same morphological variants are strongly pathogenic (also B. subtilis), when the strains are recently isolated from infected animals. The similarity between the same "S" variants of different species is proved also by the protection given by anti-anthrax serum to animals infected by B. subtilis.

Animals↗
PubMed1976

Electron capture gas chromatographic detection of acethylmethylcarbinol produced by neisseria gonorrhoeae.

Acetylmethylcarbinol (acetoin) production by Neisseria gonorrhoeae and other Neisseria species was established by gas-liquid chromatography and by mass spectrometric data. Sixty-nine isolates of Neisseria were tested by incubating them in a chemically defined fluid medium. The medium was extracted with organic solvents and derivatized with heptafluorobutryic anhydride for gas chromatography and mass spectrometry. Cultures of 58 of the same strains were tested with the conventional Voges-Proskauer reagents, and results were compared with those of gas-liquid chromatography. When glucose was used as an energy source, N. gonorrhoeae, some N. meningitidis, and N. lactamica produced enough acetoin in 16 h to be detectable by either method, whereas other Neisseria species produce amounts detectable only by gas chromatography. The conventional acetylmethylcarbinol test with the chemically defined medium and maltose as an energy source might be used to develop methods that would differentiate certain members of the genus, including the pathogenic species.

Butanones↗
PubMed2025

Genome-scale CRISPR screen identifies TMEM198 driving double membrane vesicle formation in swine alphacoronavirus and murine betacoronavirus infected cells.

COVID-19 pandemic caused by the SARS-CoV-2 which is well-publicized cross-species transmissibility. SARS-CoV-2 belongs to genus Betacoronavirus, several pathogenic alphacoronaviruses have shown similar patterns of emergence. Much less attention paid to host factors required for alphacoronavirus replication compared to those of betacoronaviruses. Here, we utilized a genome-wide CRISPR-Cas9-based screen to identify TMEM198 as a critical host protein for double-membrane vesicle (DMVs) formation during the replication of swine alphacoronavirus. Gene deletion of TMEM198 led to a reduction in the levels of viral infection in cells, whereas the ectopic expression of TMEM198 correspondingly resulted in an increase in infection levels. At the mechanistic level, TMEM198 directly binds to the C-terminal of nonstructural protein 3 (nsp3c) and nonstructural protein 4 (nsp4) to participate in the formation of DMVs. The first 35 amino acids at the N-terminal of TMEM198 are critical for the formation of DMVs and viral replication. Moreover, mice with a gene deletion of TMEM198 exhibit reduced susceptibility to the Betacoronavirus MHV. These results identify the function of TMEM198 in the formation of DMVs during the replication of swine alphacoronavirus and murine betacoronavirus.

Animals↗
PubMed1979

The origin and species of yeasts in commercial preparations of bovine semen.

Whereas yeasts were not normally isolated from raw semen samples 13% of commercial frozen semen samples and 71% of preputial washings contained yeasts. Nine genera and 25 species of yeasts have been identified from these two sources. Yeasts originating in the preputial cavity were generally saprobic members of the genera Candida, Cryptococcus, Rhodotorula, Saccharomyces, Torulopsis and Trichosporon. Those originating as contaminants during processing were more likely to be opportunistic pathogens of the genus Candida. Conception was not necessarily affected by the presence of large numbers of Candida krusei or C. macedoniensis in the uterus.

Animals↗
PubMed1976

Prophylaxis against anaerobic sepsis in bowel surgery.

Sixty-two patients were admitted to a prospective randomized controlled trial to investigate the influence of a prophylactic antibiotic, lincomycin, on anaerobic sepsis following bowel surgery. The incidence of postoperative sepsis was reduced from 45 to 18 per cent (P less than 0-025). Wound infections were reduced from 38 to 12 percent (P less than 0-05). Intra-abdominal or pelvic abscess occurred in 1 of the treated group compared with 3 controls. Septicaemia occurred after operation in 1 patient receiving lincomycin and in 3 of the controls; in 2 of the latter, pure growths of bacteroides were isolated from the blood cultures and 1 of these patients died. Although lincomycin had no influence on the number of patients who developed aerobic postoperative infections, there was a significant reduction in the incidence of sepsis due to bacteroides, which occurred in 10 of the control group compared with 1 in the lincomycin group (P less than 0-005). No patients developed complications attributable to lincomycin, such as pseudomembranous colitis. These data indicate that the genus Bacteroides are important pathogenic organisms and are responsible for postoperative morbidity. Furthermore, anaerobic sepsis can be reduced by appropriate prophylactic antibiotics.

Aged↗
PubMed1975

Herpersvirus strigis: host spectrum and distribution in infected owls.

Herpesvirus strigis, a new species of the genus Herpesvirus, is a pathogen for several species of owls in the order Srigiformes. Natural infection has been observed in the Eagle Owl (Bubo bubo L.), Long-eared Owl (Asio otus L.) and Snowy Owl (nyctea scandiaca L.) In addition the Little Owl (Athene noctua Scopolic) and Tengmalms Owl (Aegolius funereus L.) was experimentally infected. On the other hand the Tawny Owl (Strix aluco L.) and Barn Owl (Tyto albo Scopoli) proved resistant to a massive experimental infection. Of representatives from nine other orders of birds and mammals, only the Old World Kestrel (Falco tinnunculus L.) was found susceptible to this virus. Distribution of viral antigen in various organs of infected owls, as determined by immunofluorescence and by quantitative virus assay, was in accordance with the occurrence of macroscopic and microscopic lesions.

Animals↗
PubMed1979

[Immunological characteristics of the protein antigens of the family Neisseriaceae. II. The importance of an immunochemical analysis of the protein complexes for a study of taxonomy problems].

The study of antigenic interrelations in the family Neisseriaceae resulted in the isolation of 2 main immunologically separated variants of protein complexes: the first variant was characteristic of nonpathogenic and pathogenic species of the genus Neisseria as well as of 7 taxonomically undefined Neisseria species (N. lactamicus, N. cuniculi, N. ellongata, N. ovis, N. animalis, N. cinerea, N. canis) and Gemella haemolysans; the second variant was represented by the genera Branhamella and Acinetobacter. N. caviae and 3 out of 14 Neisseria strains of undefined species had no common antigens with the genera Neisseria and Branhamella. The importance of the immunotyping of protein complexes for studying the problems connected with the taxonomy of the family Neisseriaceae was considered.

Antigens, Bacterial↗
PubMed2026

Complete Genome Sequence of Atractylodes virus A, a Novel Carlavirus Infecting Atractylodes lancea.

Atractylodes lancea is an important medicinal crop, but viral diseases have become increasingly severe in recent years. Viruses in the genus Carlavirus are common plant pathogens that are primarily transmitted by aphids and can cause stunted growth and reduced yields in their host plants. In this study, a novel carlavirus, tentatively named Atractylodes virus A (AVA), was identified from A. lancea plants exhibiting virus-like symptoms. The full-length genome of AVA is 8,817 nt in length and contains six open reading frames, displaying the typical genomic organization of the genus Carlavirus. The replicase and CP exhibit 53.43% and 56.72% amino acid identity, respectively, with those of previously characterized carlaviruses, indicating that AVA represents a novel species in the genus Carlavirus. This study expands our understanding of viral diversity in A. lancea and provides a scientific foundation for the prevention and control of viral diseases as well as for resistance breeding.

Genome, Viral↗
PubMed1979

Babesia infections in man.

Only recently has it been recognized that hemotropic animal parasites of the genus babesia are also human pathogens. Similar to malaria in both symptoms and laboratory findings, acute babesiosis generally results in self-limited illness, but it can be fatal in the asplenic patient. The widely disseminated vector tick, Ixodes dammini, can transmit infection at each stage of its development, larva and nymph as well as adult.

Adult↗
PubMed1979

Characterization of two Chikungunya virus variants.

The stability of virulence and plaque size of two variants of Chikungunya virus (genus Alphavirus) were examined. Mouse pathogenicity did not coincide with infective virus levels in the brain. An increase in the average survival times of mice receiving a lethal dose of the variant which allowed prolonged survival at high doses and harvested late after infection was observed. Studies in Vero cells suggested that the number of infective virus particles produced per cell was lower with the small plaque variant, though these cells were selective for this clone. On the other hand suckling mice or antisera favoured a more virulent large plaque variant.

Animals↗