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摘要: style="FONT-FAMILY: ; FONT-SIZE: 10pt" ?="">Helicobacter pylori style="FONT-FAMILY: ; FONT-SIZE: 10pt" ?=""> performs the unique action of assimilating exogenous non-esterified cholesterol into its cell membrane. This bacterium aggressively incorporates non-esterified cholesterol into the membrane, induces its glucosylation, and uses both non-esterified cholesterol and glucosylated cholesterols as membrane lipid compositions. The reason for this assimilation of non-esterified cholesterol into the cell membrane of H. pylori has eluded investigators for many years. Recent hypotheses posit that the sterol-uptake and sterol-glucosylation contribute to the survival of H. pylori cells in different ways. The incorporation of the non-esterified cholesterol into the cell membrane fortifies the resistance of H. pylori against the antibacterial actions of phosphatidylcholines, antibiotics, and bile salts. In parallel, the glucosylation of the non-esterified cholesterol incorporated into the cell membrane serves H. pylori in two ways. First, it helps the bacterium evade host immune responses, such as phagocytosis by macrophages and activation of antigen-specific T cells. Second, it detoxifies sterols fatal to the bacterium via a novel action of sterol glucosylation recently described in another report from our group. The reluctance of H. pylori to absorb esterified cholesterol remains unexplained. A recent study by our group has demonstrated that the phosphatidylethanolamine (PE) in the outer membrane of H. pylori serves as a steroid-binding lipid the incorporation of non-esterified cholesterol into the membrane. We have also discovered that the myristic acid (C14:0) molecule attached to the PE of this bacterium plays an important role in the selective binding of non-esterified cholesterol but not esterified cholesterol....
摘要:The antibiotic batumin, produced by Pseudomonas batumici, has been shown to be highly active against 123 type and reference strains and clinical isolates of 30 Staphylococcus species (including MRSA and small colony variants—(SSCVs) of S. aureus, S. epidermidis and S. haemolyticus). Batumin activity against these bacteria did not depend on the species, origin or resistance to other antibiotics and its MIC was 0.0625 - 0.5 mg/ml. Batumin influence on biofilm formation was studied in clinical isolates of S. aureus, S. epidermidis and S. intermedius. Addition of batumin at a concentration of half of the MIC in the broth, i.e. 0.125 μg/ml, decreased the biofilm of 16 out of 20 S. aureus strains to varying degrees. Batumin was more effective against Staphylococcus strains with strong biofilm formation. Using atomic-force microscopy, it could be shown that batumin reduced the number of S. aureus ATCC 25923 adherent cells more than fourfold. The adherent cells of staphylococci were visualized as monolayers of separate islets. A detailed study of the surface of bacterial cells treated with batumin allowed to establish significant reduction of their roughness values. Observed values were typical for planktonic S. aureus cells. The obtained data explain one of the mechanisms of the antimicrobial activity of batumin, which is based оn preventing the formation of S. aureus biofilm. As such, batumin could be considered as an agent offering opportunities for the treatment of staphylococcal biofilm-associated infections....
摘要: align="justify"> style="font-family:Verdana;font-size:12px;">This review presents several types of metabolites produced by the most common fungal pathogens and their roles in fungal pathogenesis. Toxic metabolites from toxigenic fungi include compounds such as aflatoxins, trichothecenes, ochratoxins, fumonisins, zearalenone and ergot alkaloids, which display hepatotoxicity, nephrotoxicity, neurotoxicity and genotoxicity. The ability of fungi to produce and elaborate hydrolytic enzymes is associated with virulence of several pathogenic fungi. The biogenesis of siderophores is investigated as it is a mechanism of iron acquisition. In particular, these metabolites act as iron chelators and storage compounds to support pathogenic fungi to survive in mammalian hosts whose iron homeostasis is strictly regulated and prevent the formation of free radicals which are formed by free iron. Melanins clearly promote infectivity in a number of species of fungal pathogens. They interfere with oxidative metabolism of phagocytosis making the fungus relatively resistant to phagocyte attack. Several metabolies such as pullulan, mannitol, β-(1,3)-glucan, hem-binding proteins, estrogen-binding proteins, farnesol, agglutinin-like sequence proteins, glucuronoxylomannan and others also have advantages in fungal pathogenicity. The identification of fungal metabolites involved in pathogenesis, and recognition of mechanisms of pathogenesis may lead to development of new efficient anti-fungal therapies. />
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摘要:En route to its intestinal target cells Salmonella enterica passes different host niches and encounters various environmental cues. These are expected to promote Salmonella in the decision of changing its extracellular life style to intracellular. We find that prior incubation of bacteria in the presence of signals which are characteristic for the small intestine affects invasion in a model system: Salmonella grown at high osmotic pressure in the presence of bile or in amino acid rich medium, infect host cells most efficiently. Hence, Salmonella enterica modulates its infectivity in response to these stimuli which consequently determines the success of infection. Our results close the current gap between signal and actual behavior and may serve as a basis for further investigations for example if Salmonella has an adaptive prediction of environmental changes....
摘要:Emergence of multidrug-resistant tuberculosis (MDR-TB) urgently demands for simple, rapid and inexpensive methods of its detection for the effective treatment of drug resistant tuberculosis, particularly in low-income countries. A total of 113 clinical isolates of M. tuberculosis were tested for four first line antitubercular drugs by nitrate reductase assay (NRA) and were compared with standard proportion method to evaluate NRA efficacy. Results were available in 7 - 14 days by NRA as compared to proportion method which generally takes 4 - 6 weeks. The sensitivity and specificity of NRA were 98.1% and 100% for isoniazid, 95.1% and 98.6% for rifampicin, 91.4% and 94.9% for streptomycin, and 78.6% and 97.9% for ethambutol, respectively. Agreement between NRA and proportion method were 99.1%, 97.3%, 93.8%, 95.6% for isoniazid, rifampicin, streptomycin and ethambutol, respectively. NRA is easier, inexpensive and reliable method for susceptibility testing of Mycobacterum tuberculosis for isoniazid and rifampicin, the two most im- portant drugs for the treatment of tuberculosis. The reduction in susceptibility testing time, and higher sensitivity and specificity of NRA method is of fundamental importance in detecting MDR-TB....
摘要: align="justify"> The aim of this study was to detect the expression of 4 clinically-important efflux pumps in the Resistance-Nodulation-Cell Division (RND) family including MexAB-OprM, MexXY, MexCD-OprJ and MexEF-OprN in Pseudomonas aeruginosa using a combination of resistance-phenotypic markers and multiplex RT-PCR (mRT-PCR). The antibiotic substrates specific for each Mex systems were used as phenotypic markers including carbenicillin, MexAB-OprM, erythromycin, MexCD-OprJ, norfloxacin and imipenem, MexEF-OprN and gentamicin, MexXY-OprM. The methods were validated with reference strains with known genotypes of the Mex systems and the potential applicability in clinical practice was tested with clinical isolates. The results for the reference strains support that the combination of resistance phenotype and mRT-PCR is a potential-attractive method for diagnosis of efflux-mediated resistance in P. aeruginosa. Further development to make it more practical for clinical use and study in a larger number of clinical isolates is required.
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摘要:Food animals are important reservoirs of infectious pathogens. The use of antimicrobial drugs in food animals is a major source of selection of drug resistant pathogens. This study investigated a total of 1000 faecal samples of livestock and poultry between January 2012 and March 2013 to determine the prevalence rate of Salmonella species and their antimicrobial resistance profiles. Faecal samples of chicken, pig, cattle, goat and sheep (200 samples of each) were pre-enriched in Tetrathionate broth and Rappapport Vassiliadis R10 broth. The broth culture was subcultured on XLD agar and incubated. The isolates were identified by standard biochemical tests and confirmed by AP1 20E test kit. Antimicrobial susceptibility was performed by disk diffusion method. The result showed that the prevalence of Salmonella spp. in all the samples was 21.8%. Chicken faeces had the highest prevalence rate of 52.5% followed by pig faeces (40%), cattle (10%), goat (4.5%) and sheep (2%). The isolates have resistance profile ranging from 1 to 9 antimicrobial drugs. Tetracycline had the highest resistance (81%) of all the isolates followed by Streptomycin (68%). Gentamycin had the lowest resistance profile of 14%. We conclude that Salmonella species have high prevalence rate in chicken and pig, but less in cattle, goat and sheep, and that most of the isolates are resistant to most commonly used antibiotics. Effort is needed to adopt measures to control the spread of multidrug resistant pathogens to humans. Care must be taken in the use of antibiotics in farm animals to reduce the selection of multidrug resistant strains....
摘要: style="FONT-FAMILY: ; FONT-SIZE: 10pt" ?="">The semen quality of 479 men in infertile marriages, who attended the infertility clinic of OOUTH, Sagamu between May 2004 and April 2009 were analyzed. The semen samples were physically examined, microscopically analyzed and aerobically cultured. The result showed that out of 51.5% oligospermic cases recorded, 39.8% could be classified severe. Cryptozoospermia were diagnosed in 72 (15%) cases. Bacteriospermia and Necrozoospermia were found in 149 and 6 cases respectively. The predominant organism isolated was Staphylococcus aureus (50.32%) while Neisseria gonorrhoea was isolated in only 2 cases. Highest infection of 62.4% was noticed among the group with 1 style="FONT-FAMILY: ; FONT-SIZE: 10pt" ?="">% style="FONT-FAMILY: ; FONT-SIZE: 10pt" ?="">- style="FONT-FAMILY: ; FONT-SIZE: 10pt" ?=""> style="FONT-FAMILY: ; FONT-SIZE: 10pt" ?="">19% motility. From the studied population, 8.8% were azoospermic. The commonest morphological defects were pin and ragged heads (48%). style="FONT-FAMILY: ; FONT-SIZE: 10pt" ?="">It is therefore obvious that the style="FONT-FAMILY: ; FONT-SIZE: 10pt" ?="">assessment of semen quality remains one of the important steps in infertil style="FONT-FAMILY: ; FONT-SIZE: 10pt" ?="">ity interventions....
摘要:Urinary tract infections remain the most common bacterial infection in human population. They are also one of the most frequently occurring nosocomial infections, representing about 40% of all nosocomial bacterial infections world widely and associated with important medical and financial implications. This retrospective study aimed to establish the bacterial profile of UTIs in Benin. Therefore, reported data were collected from 2003 to 2012 at Menontin's Hospital in Cotonou and subjected to analyses. At the end of the study, fourteen different bacteria species were found to be associated with UTI cases in Benin. Escherichia coli was the most prevalent followed by Staphylococcus aureus. Results of the current study are helpful to the health care community of Benin in establishing the appropriate antibiotherapy for UTI patients' treatment with respect organisms into circulation....
摘要:Various kinds of organisms, including viruses, bacteria, trematodes and fungi are known carcinogens that cause cancer. Infectious identification related to cancer may lead to better treatment for both the prevention and targeting of cancer therapy. Although nearly 20% of all cancers are caused by an infection of a microbe, the amount of evidence and information regarding the mechanisms associated with oncogenesis varies dramatically from one organism to the next. This review cannot be exhaustive because we are not aware of all infections worldwide in addition to their potential mechanisms for oncogenesis. More research is required for all of the species mentioned in this review....
摘要:Methanol extracts of the dried leaves and seeds of Amaranthus viridis were collected and used for phytochemicals and antibacterial analysis. By detecting the MIC and zone inhibition, the antibacterial activity was determined against different bacterial and fungal strains. The extract yields from the leaves and seeds ranged 5.5-6.1 and 2.42%-3.72% w/w, respectively. Phytochemical investigation of this plant determines that tanins (6.07%-5.96%), saponins (53%-32%), alkaloids (13.14% - 11.42%), protiens (16.76%-24.51%) and glycosides (63.2%-32.3%) were rich in leaves. The extracts also contained appreciable levels of total phenolic contents (2.81-3.61 GAE, g/100 g), total flavanoid contents (18.4-5.42 QE, g/100 g) and DPPH free radical scavenging activity, showing IC50 (83.45-75.95 μg/mL) along with reducing power was calculated. The MIC of extracts ranged 178 - 645 μg/mL. The results of this study suggest the possibility of using the methanolic extracts in treating the diseases caused by the test organisms.

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摘要: align="justify"> We developed and evaluated a multiplex PCR (m-PCR) for application in routine diagnostic laboratories to detect Campylobacter spp. in stool samples including C. concisus, C. jejuni, and C. coli. When this m-PCR was applied on spiked faecal samples, C. concisus, C. jejuni, and C. coli were specifically identified at 105 cells/gm of faeces. To compare the sensitivity of the m-PCR with conventional culture techniques, the same spiked stool samples were cultured on an antibiotic free Columbia blood agar using the filtration technique. The detection limit of conventional culture method was 105 cells/gm of stool for C. concisus and 106 cells/gm of stool for C. jejuni and C. coli. The m-PCR was applied to test 127 faecal samples from children with gastroenteritis and the results were compared with the conventional bacterial cultures data. By this m-PCR technique, C. jejuni was detected in 7 samples, C. coli in 2 samples, and C. concisus in 7 samples. However, the conventional culture results for these samples were 6 for C. jejuni, 2 for C. coli and only one sample was positive for C. concisus. In total, 19 samples were positive for Campylobacter spp. by m-PCR while only 9 samples were positive for Campylobacter spp. by culture. In conclusion, m-PCR is more sensitive than the culture technique to detect C. concisus and other fastidious campylobacters in faeces.
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摘要:Background: The hygiene of environmental surfaces from shopping, ATM machines, telephones and computers and miscellaneous sites play role in spreading fecal and total coliform bacteria as well as pathogenic bacteria. Objectives: This study addresses the contaminated common sites by pathogenic or potentially pathogenic bacteria in Mecca, SA. Materials and Methods: A total 648 swab samples were collected and analyzed for presence or absence of pathogenic bacteria. Results: Of the total samples 422 were negative bacterial count (71%) and 226 (29%) were positive. All collected samples (100%) of glass windows in the fish markets were bacterial counted; most dominated was Bacillus spp. (n = 97) and the highest population of species was Enterococcus faecalis (n = 40) and E. coli (n = 16). Conclusion: Some public sites were very contaminated with different types of fecal coliform group of bacteria such as shopping cart handles, inner surfaces and child seats in supermarkets, and the glass windows in the fish market. Acinetobacter haemolyticus and other hemolytic bacteria were isolated from more than site....
摘要: class="MsoNormal"> lang="EN-GB">Introduction: lang="EN-GB"> Leptospirosis is a worldwide zoonosis. It is transmitted through the urine of infected animals. Currently, there is an increase of reports in many countries. In humans, it presents an ample clinical spectrum, which goes from an asymptomatic infection up to Weil syndrome, which is generally fatal. lang="EN-GB"> lang="EN-GB">Clinical Case: lang="EN-GB"> A male, 6 years of age, who started with onset fever and jaundice, handled in private means, diagnosed as viral hepatitis “A” and was referred to an institutional hospital where hepatomegaly and splenomegaly were detected. His evolution was towards graveness and, therefore, he was referred to a third level hospital with reactive Hepatitis diagnosis and to rule out lymphoma. On ad lang="EN-GB">mission, he presented liver and kidney failure, as well as metabolic acidosis and pulmonary haemorrhage that led to death 6 hours later. Confirmatory tests for hepatitis were negative; biopsies were taken post-mortem for Leptospira di lang="EN-GB">agnosis, which were positive in liver and kidney. lang="EN-GB"> lang="EN-GB">Conclusions: lang="EN-GB">Leptospirosis is a disease that may be manifested in multiple ways. It is important the understanding of this disease by the physician to improve the diagnosis and, for gen lang="EN-GB">eral population, to avoid exposure. The examination of the epidemiological history of the patient is essential.

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摘要:Antigenicity of pathogenic yeast Candida zeylanoides NBRC 10326 was found to have similar to that of Candida guilliermondii, but it was slightly different, i.e. NBRC 10326 strain cells react strongly with the factor antibodies 1, 4, and 9, and react relatively weakly with factor antibody 5. We have investigated the structural characteristic of cell wall mannan of this strain using a non-degradable method, nuclear magnetic resonance analysis. The results obtained from NMR analysis, the two-dimensional homonuclear Hartmann-Hahn, indicated that C. zeylanoides mannan contains α-1, 3-linked and β-1,2-linked oligomannosyl side chains corresponding to C. guilliermondii specific antigenic factor 9. In addition, it was found that the mannan contains β-1,2-linked oligomannosyl side chains attached to phosphate groups corresponding to anitigenic factor 5, which were not found in C. guilliermondii mannan....
摘要:Purpose: To investigate 1) the development in the incidence of ESBL-producing bacteria in hospitals and primary health care, 2) the contribution of primary health care to the incidence of ESBL-producing bacteria, and 3) the development in resistance patterns for all Escherichia coli and Klebsiella pneumoniae isolates in relation to antimicrobial consumption in hospitals and primary health care. Methods: ESBL-data were retrospectively collected from bacterial isolates from all specimens received at the Department of Clinical Microbiology from 2003 to 2011 together with the corresponding patient data. ESBL-production was detected in isolates from 1067 of 59,373 patients (1.8%) with an E. coli infection and in 263 of 8660 patients (3.0%) with a K. pneumoniae infection. Results: From 2003 to 2009, an increase in patients with an ESBL-producing isolate occurred in both hospitals and primary health care at the same time as an increased consumption of broad-spectrum antimicrobial agents was seen. Interventions to reduce prescription of cephalosporins and ciprofloxacin at the hospitals from 2010 resulted in a remarkable decrease in patients with ESBL-producing K. pneumoniae whereas a continuing increase was seen in patients with ESBL-producing E. coli both at hospitals and in primary health care. The proportion of patients with community-acquired ESBL-producing E. coli was stable with an increase of only 1.4% from 2007 to 2011. Conclusions: Reduction in prescription of broad-spectrum antimicrobial agents at the hospital level had an important impact on the incidence of ESBL-producing K. pneumoniae, but not on ESBL-producing E. coli....
摘要:Background: Staphylococcus aureus is found on all surfaces especially in public areas like hospitals and schools and on frequently touched areas like toilet and classroom door handles. Methicillin resistant Staphylococcus aureus (MRSA) is a strain of Staphylococcus aureus which is resistant to methicillin. There are two types of MRSA: Community acquired methicillin resistant Staphylococcus aureus (CA-MRSA) and hospital acquired methicillin resistant Staphylococcus aureus (HA-MRSA). MRSA in the community presents a significant reservoir that could enter into healthcare facilities and spread among patients and also a risk for immune compromised persons in the community. Methodology: The study aimed at determining the prevalence of MRSA isolated from toilet and classroom door handles as a potential source of infection to the students and the workers in selected schools in Nairobi, Kenya. The study also compared the prevalence of MRSA between boarding and non-boarding girls, boys and mixed (both girls and boys in the same school) secondary schools. Twelve secondary schools in Nairobi County were randomly selected and 306 samples from both the toilet and classroom door handles were collected using sterile swabs and transported to the laboratory. Isolation of Staphylococcus aureus was done by the use of selective media Mannitol salt agar, antibiotic susceptibility of isolates was done by disk diffusion method, and molecular detection of mecA and PVL genes were done by polymerase chain reaction (PCR). Results: The prevalence of S. aureus was 20% and 15% were MRSA positive by both Antimicrobial Susceptibility Test and PCR detection. 20% showed the presence of PVL genes, 8% showed the presence of both genes and 56% of isolates with mecA gene had PVL genes. Conclusion: The presence of MRSA in this study emphasizes the need to formulate hygiene measures to prevent possible spread of MRSA and other transmissible pathogens to students and workers in the schools....
摘要: align="justify"> Natural clays have been used by man in infections of bacterial etiology, since the first historical registers. Our attention turned to a red-colored clay, known in the northeast of Brazil as barro de louça (dish clay). These clays and other natural earth materials seem interesting to us, as the blockage of the liberation of toxins or inactivation, may be related to the interruption of infection cycles in the skin and mucous membranes. The adsorptive and absorptive properties of the mineral clays are well documented in the cure process of skin and gastrointestinal diseases. Susceptibility and bacterial tropism tests were carried out. The results were analyzed and interpreted according to the conventional microbiological protocol. The bacterial strains, Staphylococcus aureus, Escherichia coli e Pseudomonas aeruginosa, did not present a susceptibility profile to an isotonic solution of clay, but there was an increase of the bacterial tropism as the concentration of the isotonic solution was increased, being the minimal observed concentration of 100 mg/mL. Our aim is to document a type of red clay from the northeast of Brazil with possible attraction properties (Tropism) to bacteria and their toxins.
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摘要:Background: The common cause of dental infections is necrosis of the pulp of a tooth, which is followed by bacterial invasion through the pulp chamber into the deeper tissues. The bacterial infections are caused by host indigenous bacteria primarily aerobic gram positive cocci, anaerobic gram negative and gram negative rods. The aim of this study is to identify the presence of different cultivating microorganisms which cause dental infections in primary and young permanent teeth manifested by as abscesses and apical parodontitis. Material and Methods: Seventy kids ages 5 - 15 years ( 36 females, 34 males) were studied prospectively (I assume this) at the University Dental Clincal Center of Kosovo, Department of Pediatric Dentistry in cooperation with Microbiological Department of Faculty of Medicine. All patients who had clinical, and radiological confirmation of thier dental infections, followed by extraction of their teeth. Once the tooth was extracted blood and pus sample from the empty alveoli were cultured. The analysis of the sample for bacteria identification was done using the automated system VITEK 2 cards (Biomeriux, France). Results: Of 70 children's with deciduous 73.5% of them had acute infection and 26.5% chronic infection. On the other hand 75% of children with permanent dentitions had chronic and 25% acute infection. In acute infections the most common aerobic bacteria was Streptococcus group with 47% (Streptococcus mitis and oralis) followed by the Actonomyces group (Actinomyces mayeri and Actinomyces odontoliticus) and anaerobic bacteria in 34%. In chronic infections streptococcus group was the prevalent aerobic group and in anaerobic infection Actinomyces mayeri and Actinomyces naeslundi was the most representative aerobes in 21% of samples. Conclusion: The dental infections in pediatric population (5 - 15 years old) are polymicrobial predominantly anaerobic bacteria over aerobic. This study paves the way for preventives measures that need to me implemented in this group of children....
摘要: align="justify"> Background: Since the isolation of HHV-6 in 1986, extensive investigation has revealed it to be ubiquitous and responsible for the majority of cases of a common febrile rash illness of infants known as roseola. Other clinical associations including seizure disorders, encephalitis and meningitis have also been stated in various publications. Objective: The aim of the study is to find out if there is any association between HHV-6 infection and the convulsions prevailing at the Child Health Department of the Korle-Bu Teaching Hospital, Accra-Ghana. Methods and Results: Children admitted into the Department of Child Health with episode of convulsions were recruited after informed consent had been sought from subjects. Cerebrospinal fluid (CSF) and Plasma were obtained from patients. PCR directed at the detection of the large tegument protein (LTP) gene in the SIE strain of the HHV-6 in Plasma and CSF from patients was done. The mean age of study subjects was 37.44 months with 53 (64.6%) being males. There was a significant relationship between the convulsions and fever (P < 0.05). Based on CSF characteristics gathered, viral infections may be the probable cause of the observed convulsions but not malaria or bacterial infections. None of the samples from the patients had evidence of HHV-6. Conclusion: The study was unable to establish HHV-6 infection in the CSF and Plasma of patients. What role if any HHV-6 has in convulsions seen in children or neurological diseases at large merits further studies. Other neurotropic viruses need to be investigated as possible causes for the convulsions.
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