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81.
82.
Escherichia albertii is a newly emerging enteric pathogen that has been associated with sporadic infections among humans and birds. Selected coliform isolates were screened for allelic variation in 2 housekeeping genes (lysP and mdh) specific for E. albertii. The 48 strains that were identified as E. albertii were tested for 15 virulence markers and biochemical and serogical properties. All E. albertii strains were non-motile, fermented D-glucose (with gas), D-mannitol, and D-mannose, but failed to ferment lactose and other sugars. Variable positive reactions were noted for other tests. Most strains were rough or failed to agglutinate with Shigella boydii 13 antisera and E. coli antisera with few exceptions. All strains were positive for the eaeA gene, and variable numbers were positive for the cdtB, phoE, ehxA, and stx2f genes. Results illustrate the variability extent within this lineage and highlight the importance of accurately distinguishing it within the genus Escherichia and including information within commercial databases to improve their identification. 相似文献
83.
Z. Szolnoki A. Kondacs Y. Mandi A. Bodor F. Somogyvari 《Acta neurologica Scandinavica》2011,123(5):352-357
Szolnoki Z, Kondacs A, Mandi Y, Bodor A, Somogyvari F. A homozygous genetic variant of mitochondrial uncoupling protein 4 affects the occurrence of leukoaraiosis.Acta Neurol Scand: 2011: 123: 352–357.© 2010 John Wiley & Sons A/S. Objectives – We hypothesized that an appropriate balance of the mitochondrial energy production is essential in the maintenance of the glia cells in the brain. The aim of this study was to examine the roles of the rs10807344 and rs2270450 genetic variants of mitochondrial uncoupling protein 4 in the development of vascular demyelinization of the white matter of the brain, referred to as leukoaraiosis (LA). The mUCPs are presumed to be of great importance in the regulation of the mitochondrial membrane potential (MMP) and the cellular energy metabolism. Materials and methods – An analysis was performed on the clinical and genetic data on 401 LA patients without infarction and on 451 neuroimaging alteration‐free subjects. After univariate statistical approaches, logistic regression models were also used to adjust differences in significant clinical factors between the patients and controls. Results – The rs10807344 CC genotype proved to exert a protective effect on the occurrence of LA (neuroimaging alteration‐free controls: 57.7%, LA group: 44.9%, P < 0.0002; adjusted OR: 0.41, 95% CI: 0.2–0.68, P < 0.005). Conclusion – The present findings indirectly raise the possibility that a shift or imbalance in the finely regulated MMP may play a role in the development of LA. 相似文献
84.
Oxidative stress significantly contributes to cisplatin (CP)-associated cytotoxicity, and use of antioxidants could counteract such cytotoxic effects of CP. The major biochemical pathway for reactive oxygen species (ROS) formation proceeds through O2− production, which is generated by NADPH oxidase, such oxidative stress can activate p38 MAPK to intensify the cytotoxic effect of CP. We mainly aimed to study the protective effect of oxytocin (OT) on CP-induced nephrotoxicity whereas; it was previously shown to have anti-inflammatory effects in different inflammation models. Administration of OT significantly decreased the gene expression of both NADPH oxidase and P38 MAPK, nitric oxide (NO), myloperoxidase (MPO), and TBARS, furthermore it increased the renal tissue levels of antioxidants; reduced glutathione (GSH), and superoxide dismutase (SOD). Histologically, OT reduced the monocellular infiltration as well as the tubular damage in CP-induced nephrotoxicity. In conclusion OT has a powerful antioxidant effect that can alleviate the CP-induced nephrotoxicity through inhibition of NADPH oxidase and P38 MAPK resulting in improvement of kidney functions. 相似文献
85.
Elina Zueva Laila Illán Rubio Frédéric Ducongé Bertrand Tavitian 《International journal of cancer. Journal international du cancer》2011,128(4):797-804
Metastasis, the capacity of tumour cells to disseminate and grow at distant sites, is the main factor in cancer mortality. Compounds inhibiting migration and invasion of cancer cells are promising candidates for anticancer therapy strategies. We have generated nuclease‐resistant RNA ligands (aptamers) recognizing highly metastatic cells with high affinity and specificity, and inhibiting their migratory and invasive potentials. Aptamers were generated by a cell‐based subtractive SELEX technology using isogenic cell lines with similar tumorigenic potentials but opposite metastatic aggressiveness. Two aptamers, E37 and E10, bound specifically to the metastatically aggressive cell line and altered the phosphorylation of several tyrosine kinases. Fluorescent microscopy showed intracellular uptake of E37, in contrast to membrane binding of E10. Both aptamers inhibited migration of tumour cells in culture (50 and 85% inhibition with respect to control pool for E10 and E37, respectively) while only E10 inhibited cell invasion (?75% with respect to control pool). This proof‐of‐concept study demonstrates the potential of cell‐based SELEX to yield ligands that selectively recognize aggressive metastatic cells and inhibit phenotypes linked to metastatic potential. 相似文献
86.
Laila A. Mohsen Mohamed F. Amin 《The journal of maternal-fetal & neonatal medicine》2017,30(7):818-825
Objective: Evaluate two new 3D and two new 2D ultrasound formulae for fetal weight estimation against the modified Hadlock formula and compare their estimation to the actual fetal weight.Methods: Fifty pregnant females were included. Inclusion criteria: singleton pregnancy, within five days of delivery and normal or IUGR pregnancy. 3D evaluation of the fetal thigh and arm was done to calculate mid-thigh and mid-arm volumes. The actual fetal weight was recorded at delivery and compared to the estimated weights.Results: Modified Hadlock formula had higher accuracy, whereas fractional limb volume method had higher precision. Systematic errors for the modified Hadlock formula, Model 6 of fractional limb volume and the original mid-thigh soft tissue thickness methods were 2.3%, ?4.8% and 11%, respectively, whereas the random errors were 7.7%, 6.2% and 13.8%, respectively. The percentage of cases estimated within 5%, 10% and 15% of actual fetal weight were 48%, 86% and 92%, respectively, for the modified Hadlock method, whereas for the fractional limb volume method, these were 40%, 78% and 98%, respectively.Conclusion: Fractional limb volume method is a very promising method for fetal weight estimation. Its performance is not significantly different from the modified Hadlock method. 相似文献
87.
Gholam A. Peyman Muhamet Kivilcim Ana Munoz Morales John T. DellaCroce Mandi D. Conway 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2007,245(10):1461-1467
Purpose To evaluate the effect of topically administered ascorbic acid on experimentally induced corneal neovascularization in the
rat model.
Materials and methods Corneal chemical cauterization of 72 eyes in Long-Evans male rats was performed using silver nitrate/potassium nitrate sticks.
Nine groups of eight eyes were used to evaluate eight concentrations of ascorbic acid with one group of eight eyes serving
as a control. Topical instillation of 100 mg/ml non-pH-neutralized ascorbic acid was performed in one group while the remaining
seven groups were evaluated using pH-neutralized ascorbic acid in concentrations of 100 mg/ml, 50 mg/ml, 10 mg/ml, 5 mg/ml,
1 mg/ml, 500 μg/ml, and 250 μg/ml.
Results The percentage of corneal neovascularization and burn stimulus score was determined for all the eyes. The means of percent
of corneal neovascularization in ascorbic acid 100 mg/ml (non-neutralized), 100 mg/ml, 50 mg/ml, 10 mg/ml, 5 mg/ml, 1 mg/ml,
500 μg/ml, 250 μg/ml, and control group were 17.50 ± 12.80 (p = 0.001), 17.00 ± 19.30 (p = 0.001), 15.25 ± 13.26 (p = 0.001), 17.62 ± 11.89 (p = 0.001), 28.87 ± 23.08 (p = 0.001), 29.62 ± 16.91 (p = 0.001), 60.12 ± 8.50 (p = 0.04), 65.62 ± 2.26 (p = 0.185), and 68.25 ± 4.06, respectively (Tables 1 and 2). All animals had a burn score of 2+ or higher (Table 1).
Conclusion Ascorbic acid applied in a topical solution appears to inhibit corneal neovascularization in the rat model of inflammatory
neovascularization in concentrations in a dose-dependent manner. The optimal dose-effect relation was in our model found in
concentrations between 1 mg and 500 μg/ml. At concentrations below 500 μg/ml there was no statistically significant inhibition
in the degree of corneal neovascularization compared to control.
None of the authors has any proprietary interest in any technique or product described herein. 相似文献
88.
Tincusi BM Jiménez IA Bazzocchi IL Moujir LM Mamani ZA Barroso JP Ravelo AG Hernández BV 《Planta medica》2002,68(9):808-812
Twelve known diterpenes 1 - 11 and 13, and three known sesquiterpenes 14 - 16, along with a new C(20) - C(15) terpenoid 17, with a structure based on an unprecedented skeleton in which a labdane diterpene is linked to a monocyclic sesquiterpene by an ester bridge, were isolated from the oleoresin of the Peruvian medicinal plant Copaifera paupera (Herzog) Dwyer (Leguminosae). Their structures were elucidated on the basis of spectral analysis, including homo- and heteronuclear correlation NMR experiments (COSY, ROESY, HMQC and HMBC), and by comparison with data in the literature. The leishmanicidal, antimicrobial, cytotoxic, and aldose reductase inhibitory activities were studied. Compounds 1 and 11 showed significant antimicrobial activity (MIC < 10 microg/ml) against Gram-positive bacteria, comparable with cephotaxime used as control. Compound 2 exhibited moderate cytotoxic activity against four cancer cell lines. 相似文献
89.
Background
Brucellosis affects human populations in many developing countries including the Middle East, and Latin America where it is still endemic. It has been prevalent in Jordan for years, where 7842 cases of human brucellosis were registered at the Ministry of Health during 10 year-period. This study was initiated by the recent increase in the number of human cases diagnosed in a rural area in the Northern Jordan to help assess the status of the disease in that area. For this purpose blood specimens from brucellosis suspected cases were tested by serology, culture and PCR.Methods
Peripheral blood specimens from 50 healthy control subjects and 165 seropositive patients having compatible signs and symptoms that were clinically diagnosed to have brucellosis were tested by blood culture, and by PCR. The PCR assay used genus-specific primers from the conserved region of the 16S rRNA sequence, which showed high specificity for the Brucella spp.Results
Diagnosis of Brucella was established by PCR in 120 cases (72.7%). All of them were seropositive and 20 were positive by culture. Forty-eight of 58 (82.8%) of the relapsed cases two months after completing the treatment with an increase in the previous serological titers were positive by PCR. The assay has 85.7% positive predicative value, 100% sensitivity and specificity since it correctly identified all cases that were positive by blood cultures, 95.8% by serology and none of the control group was positive.Conclusions
Results showed that PCR assay can be applied with serology for the diagnosis of brucellosis suspected cases and relapses regardless of the duration or type of the disease without relying on the blood cultures, especially in chronic cases.90.
Partanen T Johansson M Ahrens W Sala M Wesseling C Boffetta P Brenes F Font C Frentzel-Beyme R Garau I Janer G Kallas-Tarpila T Kogevinas M Loponen M Østergren L Peltomäki P Solér MD Svanström L Tempel J Neuvonen K 《Preventive medicine》2002,35(3):232-240
BACKGROUND: A simple empirically based method for assessment of the feasibility of workplace health promotion programs is described, focusing on cancer hazards (lifestyles, workplace hazards, deficient early detection). The basic components of feasibility are addressed: extent of hazards; needs of employees for hazard reduction and acceptability of WHP; and social context. METHODS: The procedure consists of six modules: guidelines on feasibility assessment; employee questionnaire; interview checklists for probing attitudes of management and partners (social context); data form; debriefing; and assessment of feasibility. Pretesting was completed in 16 workplace communities representing industry, construction, transport, telecommunications, health care, lodging and catering, teaching, and municipality jobs in five countries; a total of 1,085 subjects completed the employee questionnaire on health hazards, needs, and acceptability. RESULTS: The method demonstrated its utility in obtaining and summarizing the necessary data. Feasibility was assessed for the 16 test communities. CONCLUSION: The procedure can be customized; it has a high degree of face validity or understandability, and it is applicable in a wide variety of settings. 相似文献