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Y. M. Somorin* and S. A. Bankole
Abstract: The presence of fungal contaminants in Ofada and Abakaliki rice varieties under storage in Lagos and Ogun States, Nigeria were examined. The fungal species isolated from the Ofada rice were Actinomycetes spp., Aspergillus flavus, Aspergillus niger, Aspergillus tamarii, Cladosporium sphaerospermum, Fusarium compacticum, Fusarium oxysporum, Fusarium proliferatum, Penicillium oxalicum, Rhizopus nigricans, Rhizopus oryzae and Saccharomyces cerevisiae. The Abakaliki rice was contaminated with A. flavus, A. niger, A. tamarii, F. compacticum, F. oxysporum, F. proliferatum, Penicillium citrinu, P. oxalicum, R. nigricans, R. oryzae and S. cerevisiae. A. niger (80%) was the predominant fungal species while Actinomycetes spp. (6.7%) was the least isolated. Some of these fungi are known to produce mycotoxins which have several health and economic implications. The presence of such species as seen in this study may show a potential risk of mycotoxin contamination in Ofada and Abakaliki rice varieties.[...] Read More.
Keywords: Fungi, contaminants, Ofada, Abakaliki, rice, mycotoxin, mycoflora.
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E. A. Ophori* and E. C. Wemabu
Abstract: The study was aimed at determining the bacterial agents of the upper respiratory tract infection (URTI) and the susceptibility of isolates to propolis. Propolis extract was obtained by 70% ethanol and serial dilutions of 0.25, 0.5, 1, 2, 4, 8 and 10 µg/ml prepared. A total of 250 throat swabs were obtained from patients (age between 15 - 30 years) which were diagnosed with upper respiratory tract infection attending the central hospital, Benin City. Samples were collected between February and December, 2008 from 142 (56.8%) males and 108 (43.2%) females, inoculated on blood agar, eosin methylene blue agar and chocolate agar and incubated at 37°C for 24 - 48 h aerobically except for chocolate agar which was incubated microaerophically. The isolates were characterized by standard microbiological procedures. Of the 250 samples, 160 (64%) had positive cultures with Haemophilus influenzae having the highest prevalence (20.8%), followed by Klebsiella pneumoniae (19.2%), Streptococcus pneumoniae (12.0%), Moraxella catarrhalis (10%), Streptococcus pyogenes (2%). The highest rate of isolates was from the age group of 15 - 18 years (91). This was significantly higher than other groups p > 0.05. M. catarrhalis and S. pyogenes were not isolated in age group 23 – 26. propolis antimicrobial activity revealed that all isolates were sensitive to propolis at all concentrations with K. pneumoniae and S. pneumonia having zones of inhibition of 32 and 30 mm respectively. The findings suggest that propolis is a very effective antimicrobial agent for the treatment and management of URTI caused by bacterial species.[...] Read More.
Keywords: Upper respiratory tract infection, minimum inhibitory concentration, propolis, bacteria, antimicrobial activity.
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文章
Naoual Jamaly, Abdelaziz Benjouad, Roberta Comunian, Elisabetta Daga and Mohammed Bouksaim*
Abstract: Twenty three Enterococcus durans isolates collected from Moroccan dairy products were identified by species-specific PCR and their technologically relevant biochemical properties were studied. According to biochemical activities, the majority of the strains displayed weak acidification and autolysis activities in milk. In contrast, they showed high extracellular proteolytic activity. All isolates produced exopolysaccharides and most of them could metabolize citrate and tolerate a high concentration of nisin. Absence of vancomycin resistance and haemolytic activity may suggest the use of these isolates as adjunct starters in food fermentations process.[...] Read More.
Keywords: Enterococcus durans, Moroccan dairy products, species-specific PCR (Polymerase chain reaction), biochemical properties, adjunct starter cultures.
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Lan Liu*, Xuesong Peng, Lijuan Chu, Qian Liu, Juan Xiong, Chunmei Jing, Yongwu Xia and Yu Shi
Abstract: Living donor liver transplantation (LDLT), which was first demonstrated in 1989, has now been widely used to cure many late-stage hepatic diseases and has achieved huge success, especially in the pediatric field. However, accumulated studies indicate that early-stage infection after LDLT is the main cause leading to its failure and the death of the patient. Here, we retrospectively analyzed 25 cases (from 2006 to 2009) of infections of children in our hospital, underwent LDLT and their correlated factors. To identify the factors most closely related to early stage infection, we categorized early stage infection levels as either mild, moderate or severe and we compared their related risk factors, including total length of stay in hospital (TLSH), length of stay in the intensive care unit (LSI), duration of catheterization (DC), length of pre-/post-operative antimicrobial agent application, length of immuno-suppressant agent application (LISA) and underlying diseases postoperatively. The results revealed the following. (i) Of 25 patients, 24 recipients were infected to various extents: 6 cases of mild infection, 14 cases of moderate infection and 4 cases of severe infection (one patient died). (ii) TLSH, LSI and durations of preoperative (DPAA) and postoperative (DPOAA) antimicrobial agent application were statistically different between the severe and moderate infection groups (P = 0.03 (TLSH), 0.004 (LSI), 0.003 (LAPP), 0.005 (DPOAA). (iii) Between the severe and mild infection groups, the TLSH (P = 0.016), LSI (P = 0.015), DAPP (P = 0.007) and DPOAA (P = 0.001) were also significantly different. (iv) In the case of LISA, only methylprednisolone (P = 0.01) and the calcineurin inhibitor ciclosporin A (P = 0.009) showed statistically significant differences between the moderate and mild infection groups. (v) Biliary atresia is the predominant underlying liver disease. (vi) In contrast to previous findings, there was no significant difference in DC among the three infection groups. (vii) Of all the 25 patients, 24 survive till now and the only one died was diagnosed as portal vein thrombosis (PVT) combined with high white blood count (>30 x 109/l) in venous blood. DPAA, DPOAA and biliary atresia are the risk factors most closely related to infection during liver transplantation in children, an observation worthy of future investigation. To avoid long term DPAA and long term DPOAA induced early severe infection, nosocomial infection control and drug resistant bacteria monitoring are worthy to be concerned after LDLT in children.[...] Read More.
Keywords: Living donor liver transplantation, risk factor, children.
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S. A. A. Al-Rashed, F. D. A. Bakar, M. Said, O. Hassan, A. Rabu, R. M. Illias and A. M. A. Murad*
Abstract: An endochitinase, Cht2, from Trichoderma virens UKM1 was expressed in the methylotrophic yeast Pichia pastoris, and its biochemical properties were characterized. Both the cht2 gene and its cDNA have been cloned and sequenced, the endochitinase gene cht2 encodes 321 amino acids from an open reading frame comprised of an 1169 bp nucleotide sequence separated by three introns. Cht2 is predicted to be an extracellular enzyme due to the presence of a signal peptide of 20 amino acids. Cht2 cDNA was cloned into the pPICZaC expression vector under the regulation of a methanol-inducing promoter and transformed into P. pastoris X33. Expression in P. pastoris showed that the recombinant Cht2 was secreted into the culture medium with a protein size of approximately 35 kDa when induced with 0.5% methanol. Biochemical characterization of the partially purified enzyme showed a specific enzyme activity of 1.34 U/mg towards colloidal chitin at a pH of 6.0 and at a temperature of 35°C. The enzyme showed optimal activity at this pH and temperature and also showed higher affinity toward colloidal chitin in comparison to glycol chitin. It is stable in the pH range of 5.0 - 7.0 and in the temperature range of 30 - 55°C, where it retained more than 70% of its residual activity.[...] Read More.
Keywords: Endochitinase, Trichoderma virens, recombinant, characterization.
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S. E. Baidoo, S. C. K. Tay and H. H. Abruquah*
Abstract: Intestinal helminths are among the most common and widespread of human infections, contributing to poor nutritional status, anaemia and impaired growth. Anaemia and iron deficiency in pregnancy is a major public health problem in developing countries, but their causes are not always known. The objective of this study was to assess the prevalence and severity of anaemia and iron deficiency and their association with helminths, among pregnant women in the Ashanti region of Ghana. A cohort study was carried out in the Sekyere east district of the Ashanti region of Ghana. 108 pregnant women were followed until 5-10 weeks postpartum, during the period of December 2005 - November 2006. Haemoglobin and total serum iron concentrations were evaluated in venous blood samples and helminths infections were evaluated in stool samples in each trimester using standard methods. Of the 108 pregnant women, 54.9% were found to be anaemic. The highest prevalence of anaemia and low iron stores (57.4 and 32.4%, respectively) were found in the second trimester. Only 17.6% had evidence of helminths infection, with Necator americanus (hookworm) being the commonest (13.9%). There was a significant association between hookworm infection and low iron stores. The study concluded that hookworm infection is a strong predictor of iron status. These findings reinforce the need to provide anthelminthic therapy to infected women before conception as public health strategy in reducing the prevalence of hookworm infection in addition to providing nutritional and iron supplements to effectively control anaemia in pregnancy.[...] Read More.
Keywords: Intestinal helminth, anaemia, paragravids, primigravids.
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文章
Maras Meltem*, Akman Yildiz, Yula Erkan and Gökmen Tülin
Abstract: In response to osmotic stress, gram positive bacteria Streptococcus agalactiae and enterobacteria Escherichia coli accumulates compatible solutes from the medium, stress response systems may enable bacteria to adapt cellular response and survival systems to a variety of stress conditions. S. agalactiae and E. coli strains have a transporter for carnitine that can respond to osmotic stress by regulating its own activity. Brain heart infusion (BHI) broth medium with 1 mM L-carnitine was the medium with the highest growth to be observed. The growth of the E. coli strain was faster than the growth of S. agalactiae strain. S. agalactiae and E. coli are known as bacteria being hard to grow at the laboratory tests for making clinical diagnosis. The medium with L-carnitine factor used in laboratory tests accelerates the bacterial growth.[...] Read More.
Keywords: Bacterial growth, carnitine, osmoprotectant, Streptococcus agalactiae, Escherichia coli.
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文章
O. E. Agbagwa* and N. Frank - Peterside
Abstract: The antibacterial effect of eight unprocessed commercial honey sold in some local markets in Nigeria were investigated. These samples were selected to examine and compare their ability to inhibit the growth of Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Proteus mirabilis. The test organisms were isolated from wound swabs of patients at the University of Port Harcourt Teaching Hospital (UPTH), Nigeria. Agar diffusion method was employed to ascertain degree of sensitivity of the isolates to different honey samples. Different honey samples showed varying degrees of antibacterial activity. Excellent antibacterial activity was observed with respect to honey from northern Nigeria with zones of inhibition of 17.0 mm. Next to it was honey from southern, eastern and western Nigeria with zones of inhibition of 15.4, 13.5 and 11.6 mm, respectively. P. aeruginosa and P. mirabilis showed less antibacterial activity and can be regarded as being resistant to the inhibitory effects of honey. Investigated honey samples began to significantly inhibit microorganisms at 80 and 100% concentrations, demonstrating that commercial honey sold locally in Nigerian markets has lesser antibacterial effects on microorganisms.[...] Read More.
Keywords: Nigeria, antibacterial activity, honey, zone of inhibition.
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文章
Okpala N. Gloria* and A. N. Moneke
Abstract: The effect of heavy metals (zinc, cadmium, chromium and lead) at concentrations 50, 100 and 500 g/ml of the heavy metal salts on glyphosate utilization by some bacterial species isolated from rice fields were studied, the addition of lead (Pb), cadmium (Cd) and zinc (Zn) to the glyphosate mineral salt medium used in growing the Acetobacter sp. significantly (P < 0.05) increased the rate of glyphosate utilization as indicated by the increase in the growth of the organism and could be attributed to easy uptake of the metal-glyphosate complex by the organism. The growth of Pseudomonas fluorescens was enhanced in the presence of zinc in the glyphosate medium, when compared to its growth in the medium without the heavy metals. This was followed by lead, cadmium and chromium, respectively.[...] Read More.
Keywords: Glyphosate herbicide, utilization, metal-glyphosate complex.
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Ebrahim Rahimi*, Hamid Reza Kazemeini, Saman Safaei, Karim Allahbakhshi, Manouchehr Momeni, Majid Riahi
Abstract: Campylobacter species are common bacterial pathogens causing gastroenteritis in humans worldwide and the consumption of poultry meats is suspected to be the leading cause of this illness. This study was therefore conducted to determine the prevalence of Campylobacter spp. from retail raw meats in Ahvaz, Iran. From July 2009 to February 2010, a total of 215 raw meat samples from chicken (n = 60), turkey (n = 50), sheep (n = 50) and goat (n = 45) were purchased from randomly selected retail outlets in Ahvaz, Iran and were evaluated for the presence of Campylobacter. Campylobacter spp. isolated from 60 of 215 meat samples (27.9%) examined. The highest prevalence of Campylobacter spp. was found in chicken meat (61.7%), followed by turkey meat (36.0%), sheep meat (6.0%) and goat meat (4.4%). The most prevalence Campylobacter species isolated from meat samples was Campylobacter jejuni (88.3%), the remaining isolates were Campylobacter coli (11.7%). All 60 Campylobacter strains identified as C. jejuni and C. coli were also positive by using polymerase chain reaction (PCR). Significantly higher prevalence rates of Campylobacter spp. (P < 0.05) were found in the meat samples taken in summer (44.1%). Furthermore, to ensure food safety, poultry meats must be properly cooked before consuming.[...] Read More.
Keywords: Campylobacter, raw meat, chicken, turkey, sheep, goat.
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