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1.
Prof. Dr. W. Graninger Dr. D. Fleischmann Dr. Laleh Aram Doz. Dr. B. Schneeweiβ Dr. F. Stockenhauber 《Infection》1992,20(1):9-11
Summary We evaluated a bioluminescence assay as a screening test for the detection of bacteriuria in pregnancy. A total of 1,000 urine specimens from a randomly selected group of pregnant women undergoing prenatal surveillance was investigated. Sequential dilution of urine specimens on CLED agar plates served as a reference method. Set against the reference group, bioluminescence screening scored a 93% sensitivity, a 78% specificity and a 99% predictive accuracy for negative results. All urine specimens were also analysed chemically for the presence of nitrite and leucocyte esterase by dip sticks. Dip sticks proved to be insufficient because of poor sensitivities of 54% and 59%, respectively. The bioluminescence assay is an effective, time- as well as labor-saving but questionably cost-effective method for the detection of bacteriuria in pregnancy.
Rascher Nachweis der Bakteriurie bei Schwangeren
Zusammenfassung In der vorliegenden Studie prüften wir die klinische Wertigkeit eines Biolumineszenz-Verfahrens zum Nachweis der Bakteriurie bei Schwangeren. Insgesamt wurden 1000 Routine-Harnproben von Schwangeren untersucht. Als Referenzmethode diente die sequentielle Verdünnung der Harnproben und Ausstreichen auf CLED-Agarplatten. Eine signifikante Bakteriurie konnte mit der Biolumineszenz-Methode mit einer Sensitivität von 93% und einer Spezifität von 78% erkannt werden. Die Voraussagewahrscheinlichkeit für negative Resultate war 99%. Gleichzeitig untersuchten wir alle Harnproben auf Vorhandensein von Nitrit und Leukozyten-Esterase mittels Teststreifen. Die Sensitivitäten lagen nur bei 54% bzw. 59%. Mit Hilfe der Biolumineszenz-Methode kann eine signifikante Bakteriurie bei Schwangeren rasch, verläßlich, aber nur bei relevanter Probenanzahl auch kostengünstig nachgewiesen werden.相似文献
2.
Luis Gerardo Ortega-Prez Jonathan Saúl Pin-Simental Oliver Rafid Magaa-Rodríguez Alejandro Lopz-Mejía Luis Alberto Ayala-Ruiz Aram Josu García-Caldern Daniel Godínez-Hernndez Patricia Rios-Chavez 《Pharmaceutical biology》2022,60(1):1384
ContextCallistemon citrinus Skeels (Myrtaceae) exhibits many biological activities.ObjectiveThis study analyzes for the first time, the toxicity, obesogenic, and antioxidant effects of C. citrinus in rats fed with a high fat-fructose diet (HFFD).Materials and methodsFour studies using male Wistar rats were conducted: (a) 7 groups (n = 3): control (corn oil) and ethanol extract of C. citrinus leaf (single oral dose at 100–4000 mg/kg) for acute toxicity; (b) 2 groups (n = 8): control (corn oil) and C. citrinus (1000 mg/kg/day) for 28 days for subacute toxicity; (c) 3 groups (n = 4) with single oral dose of lipid emulsion: control (lipid emulsion), C. citrinus and orlistat (250 and 50 mg/kg, respectively) for lipid absorption; (d) 4 groups (n = 6): control (normal diet) and 3 groups fed with HFFD: HFFD only, C. citrinus and simvastatin (oral dose 250 and 3 mg/kg, respectively) for 13 weeks. Antioxidant enzymes and biomarkers were evaluated and inhibition of pancreatic lipase was determined in vitro.ResultsToxicological studies of C. citrinus showed no differences in biochemical parameters and lethal dose (LD50) was higher than 4000 mg/kg. C. citrinus inhibited pancreatic lipase activity, with IC50 of 392.00 µg/mL, and decreased lipid absorption by 70%. Additionally, it reduced the body weight 22%, restored the activities of antioxidant enzymes, and reduced the biomarkers of oxidative stress.ConclusionsCallistemon citrinus showed an effect against oxidative stress by reducing biomarkers and induced antioxidant system, without toxic effects. 相似文献
3.
Jeffrey Kimbrel Joseph Moon Aram Avila-Herrera Jose Manuel Martí James Thissen Nisha Mulakken Sarah H. Sandholtz Tyshawn Ferrell Chris Daum Sara Hall Brent Segelke Kathryn T. Arrildt Sharon Messenger Debra A. Wadford Crystal Jaing Jonathan E. Allen Monica K. Borucki 《Viruses》2022,14(12)
Genetic analysis of intra-host viral populations provides unique insight into pre-emergent mutations that may contribute to the genotype of future variants. Clinical samples positive for SARS-CoV-2 collected in California during the first months of the pandemic were sequenced to define the dynamics of mutation emergence as the virus became established in the state. Deep sequencing of 90 nasopharyngeal samples showed that many mutations associated with the establishment of SARS-CoV-2 globally were present at varying frequencies in a majority of the samples, even those collected as the virus was first detected in the US. A subset of mutations that emerged months later in consensus sequences were detected as subconsensus members of intra-host populations. Spike mutations P681H, H655Y, and V1104L were detected prior to emergence in variant genotypes, mutations were detected at multiple positions within the furin cleavage site, and pre-emergent mutations were identified in the nucleocapsid and the envelope genes. Because many of the samples had a very high depth of coverage, a bioinformatics pipeline, “Mappgene”, was established that uses both iVar and LoFreq variant calling to enable identification of very low-frequency variants. This enabled detection of a spike protein deletion present in many samples at low frequency and associated with a variant of concern. 相似文献
4.
Laleh Ehsani Rishie Seth Stephanie Bacopulos Arun Seth Adeboye O. Osunkoya 《Tumour biology》2013,34(2):787-791
The distinction between renal oncocytoma and renal cell carcinoma, especially chromophobe renal cell carcinoma and clear cell carcinoma with oncocytic features, is important due to the different biologic potentials of these tumors. RING E3 ligases have the subject of intense studies for their roles in many diseases including cancer and as potential therapeutic targets. All RING E3 ligases, including BCA2, contain a consensus protein sequence that would complex two or more zinc ions in the expressed protein. Identification of which ubiquitin ligases specifically affect distinct cellular processes is essential to the development of targeted therapeutics in these tumors. The ubiquitin–proteasome system regulates the turnover of proteins that have essential roles in the cell cycle, apoptosis, DNA damage repair, and in protein trafficking, which makes this pathway a target for oncogenic events. In this study, we investigated expression of BCA2 in renal oncocytoma and renal cell carcinoma. A total of 158 patients were included in the study. Our study has shown that 114/114 (100 %) cases of renal cell carcinoma were negative for BCA2. All 38 (100 %) cases of renal oncocytoma were positive for BCA2, and 6/6 (100 %) cases designated as oncocytic neoplasm which favor oncocytoma were also positive for BCA2. This is the first study to date evaluating the expression of BCA2 in renal oncocytoma. BCA2 could serve as a marker that may be utilized in the distinction between renal oncocytoma and its mimickers. 相似文献
5.
Abraham Khan Aram Kim Cassandra Sanossian Fritz Francois 《World journal of gastroenterology : WJG》2016,(4):1627-1638
Gastroesophageal reflux disease(GERD) is a frequently encountered disorder. Obesity is an important risk factor for GERD, and there are several pathophysiologic mechanisms linking the two conditions. For obese patients with GERD, much of the treatment effort is focused on weight loss and its consistent benefit to symptoms, while there is a relative lack of evidence regarding outcomes after novel or even standard medical therapy is offered to this population. Physicians are hesitant to recommend operative anti-reflux therapy to obese patients due to the potentially higher risks and decreased efficacy, and these patients instead are often considered for bariatric surgery. Bariatric surgical approaches are broadening, and each technique has emerging evidence regarding its effect on both the risk and outcome of GERD. Furthermore, combined antireflux and bariatric options are now being offered to obese patients with GERD. However, currently Rouxen-Y gastric bypass remains the most effective surgical treatment option in this population, due to its consistent benefits in both weight loss and GERD itself. This article aims to review the impact of both conservative and aggressive approaches of obesity treatment on GERD. 相似文献
6.
Parisa Akhlaghi Hashem Miri-Hakimabad Laleh Rafat-Motavalli 《Journal of radiation research》2015,56(4):646-655
In order to establish an organ and effective dose database for Iranian children undergoing computed tomography (CT) examinations, in the first step, two Iranian 11-year-old phantoms were constructed from image series obtained from CT and magnetic resonance imaging (MRI). Organ and effective doses for these phantoms were calculated for head, chest, abdomen–pelvis and chest–abdomen–pelvis (CAP) scans at tube voltages of 80, 100 and 120 kVp, and then they were compared with those of the University of Florida (UF) 11-year-old male phantom. Depth distributions of the organs and the mass of the surrounding tissues located in the beam path, which shield the internal organs, were determined for all phantoms. From the results, it was determined that the main organs of the UF phantom receive smaller doses than the two Iranian phantoms, except for the urinary bladder of the Iranian girl phantom. In addition, the relationship between the anatomical differences and the size of the dose delivered was also investigated and the discrepancies between the results were examined and justified. 相似文献
7.
Regenerative Potential of Human Schneiderian Membrane: Progenitor Cells and Epithelial‐Mesenchymal Transition 下载免费PDF全文
A.I. Derjac‐Aramă C. Sarafoleanu C.M. Manea M.I. Nicolescu A.D. Vrapciu M.C. Rusu 《Anatomical record (Hoboken, N.J. : 2007)》2015,298(12):2132-2140
An innate osteogenic potential of the Schneiderian membrane (SM) is progressively assessed in studies ranging from non‐human species to human subjects. It has relevance for endosteal placement and osseointegration. Nestin‐expressing osteogenic progenitor cells are allegedly involved in bone formation and remodelling. Nestin phenotype was not assessed previously in human SM. We therefore aimed to fill that particular gap in the literature. Bioptic samples of human adult SM were obtained during surgery from eight adult patients, operated for non‐malignant pathologies. Immunohistochemistry on paraffin‐embedded tissue samples used primary antibodies against nestin, CD45, CD146, cytokeratin 7 (CK7), and alpha‐smooth muscle actin (α‐SMA). Nestin expression was consistently found in endothelial cells, and was scarcely encountered in pericytes, putative stromal stem/progenitor cells, as well as in glandular epithelial cells. Moreover, woven bone formation in the periosteal layer of the SM can also be regarded as evidence of the osteogenic potential of this membrane. Nestin and CD45 expression in cells of the primary bone supports the osteogenic potential of SM nestin‐expressing cells and a possible involvement of hematopoietic stem cells in maxillary sinus floor remodeling. CD146, a known inducer of epithelial‐mesenchymal transition (EMT), was expressed in epithelia, as was CK7. Isolated stromal cells were found expressing CD146, CK7 and α‐SMA, suggesting that regenerative processes happening in the SM may also involve processes of EMT which generate stem/progenitor cells. This study provides additional evidence for the regenerative potential of the Schneiderian membrane and identifies potential roles for cells of its stem niche in osteogenesis. Anat Rec, 298:2132–2140, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
8.
Management of incisional scar is intimately connected to stages of wound healing. The management of an elective surgery patient begins with a thorough informed consent process in which the patient is made aware of personal and clinical circumstances that cannot be modified, such as age, ethnicity, and previous history of hypertrophic scars. In scar prevention, the single most important modifiable factor is wound tension during the proliferative and remodeling phases, and this is determined by the choice of incision design. Traditional incisions most often follow relaxed skin tension lines, but no such lines exist in high surface tension areas. If such incisions are unavoidable, the patient must be informed of this ahead of time. The management of a surgical incision does not end when the sutures are removed. Surgical scar care should be continued for one year. Patient participation is paramount in obtaining the optimal outcome. Postoperative visits should screen for signs of scar hypertrophy and has a dual purpose of continued patient education and reinforcement of proper care. Early intervention is a key to control hyperplastic response. Hypertrophic scars that do not improve by 6 months are keloids and should be managed aggressively with intralesional steroid injections and alternate modalities.
Graphical Abstract
相似文献9.
10.
Weihua Zheng Nicholas P. Schafer Aram Davtyan Garegin A. Papoian Peter G. Wolynes 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(47):19244-19249
We investigate protein–protein association using the associative-memory, water-mediated, structure, and energy model (AWSEM), a coarse-grained protein folding model that has been optimized using energy-landscape theory. The potential was originally parameterized by enforcing a funneled nature for a database of dimeric interfaces but was later further optimized to create funneled folding landscapes for individual monomeric proteins. The ability of the model to predict interfaces was not tested previously. The present results show that simulated annealing of the model indeed is able to predict successfully the native interfaces of eight homodimers and four heterodimers, thus amounting to a flexible docking algorithm. We go on to address the relative importance of monomer geometry, flexibility, and nonnative intermonomeric contacts in the association process for the homodimers. Monomer surface geometry is found to be important in determining the binding interface, but it is insufficient. Using a uniform binding potential rather than the water-mediated potential results in sampling of misbound structures that are geometrically preferred but are nonetheless energetically disfavored by AWSEM, as well as in nature. Depending on the stability of the unbound monomers, nonnative contacts play different roles in the association process. For unstable monomers, thermodynamic states stabilized by nonnative interactions correspond to productive, on-pathway intermediates and can, therefore, catalyze binding through a fly-casting mechanism. For stable monomers, in contrast, states stabilized by nonnative interactions generally correspond to traps that impede binding. 相似文献