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Mycobacterium fortuitum infections of sternotomy wounds have been successfully treated with ofloxacin, a fluoroquinolone. We studied the MBCs and MICs in vitro of this antibiotic on the organism under neutral pH (7) and acidic pH (5) and found marked escalation of these values under the latter condition. This provides hints on the therapy of these infections under in vivo settings. 相似文献
93.
Early-onset colorectal cancer (EOCRC) has seen an alarming rise worldwide over the past two decades. The reason for this global trend is poorly understood. EOCRC appears to have its own unique clinical and molecular features when compared with late-onset colorectal cancer. Younger patients appear to have more distal or rectal disease, a more advanced stage of disease at presentation, and more unfavorable histological features. Identifying risk factors for EOCRC is the first step in mitigating the rising burden of this disease. Here we summarize several noteworthy biological factors and environmental exposures that are postulated to be responsible culprits. This can hopefully translate in clinical practice to the development of better risk stratification tool for identifying high-risk individuals for early colorectal cancer screening, and identifying areas needed for further research to curb this rising trend. 相似文献
94.
R C Lui M C LaRegina D R Herbold J A Stern F E Johnson 《The Journal of surgical research》1987,43(3):286-295
Many anti-cancer drugs cause infertility. Regional delivery of these agents is a potential method to avoid this problem. We investigated the protective effect of normothermic testicular circulatory arrest on gonadal toxicity during doxorubicin administration in the Sprague-Dawley rat. Four groups of eight rats each were used. Animals in group 1 received no treatment. Rats in group 2 were anesthetized and received a bolus of intravenous doxorubicin (6 mg/kg). In groups 3 and 4, normothermic circulatory isolation of the left testis was induced by cross-clamping of the spermatic cord and gubernaculum immediately before doxorubicin administration. This was maintained for 15 min after doxorubicin administration in group 3 and for 45 min in group 4. Cessation and return of testicular blood flow were confirmed by Doppler. On Day 56, all rats were killed and necropsied. Testicular toxicity was evaluated qualitatively by histology and quantitatively by measurement of testicular weight, sperm count, repopulation index, and epididymal index. The results indicated that 15 min of testicular circulatory isolation mitigated testicular toxicity to a small extent and that 45 min of circulatory isolation provided moderate protection against doxorubicin-induced testicular toxicity. 相似文献
95.
Renal vein thrombosis can occur as a complication of nephrotic syndrome. We present the case of a young man with nephrotic syndrome caused by minimal change disease who developed acute inferior vena cava and left renal vein thrombosis. He was treated initially with intravenous heparin. Because of the persistence of severe left flank pain and gross hematuria, local infusion of recombinant tissue plasminogen activator was tried, with resolution of thrombi and subsidence of symptoms. Functional preservation of the involved kidney is good, as indicated by Tc-99m DMSA scan (involved kidney, 47.4%; uninvolved kidney, 52.6%). Anticoagulation is usually recommended as the treatment of choice in renal vein thrombosis. We believe that in cases with critical presentations, such as bilateral involvement, extension into inferior vena cava, acute renal failure, pulmonary embolism or severe flank pain, thrombolytic therapy should be considered as a second-line treatment if good response is not obtained with heparin. 相似文献
96.
Rachel M. Lucia Wei-Lin Huang Khyatiben V. Pathak Marissa McGilvrey Victoria David-Dirgo Andrea Alvarez Deborah Goodman Irene Masunaka Andrew O. Odegaard Argyrios Ziogas Patrick Pirrotte Trina M. Norden-Krichmar Hannah Lui Park 《Environmental health perspectives》2022,130(4)
Background: Glyphosate is the most commonly used herbicide in the world and is purported to have a variety of health effects, including endocrine disruption and an elevated risk of several types of cancer. Blood DNA methylation has been shown to be associated with many other environmental exposures, but to our knowledge, no studies to date have examined the association between blood DNA methylation and glyphosate exposure.Objective: We conducted an epigenome-wide association study to identify DNA methylation loci associated with urinary glyphosate and its metabolite aminomethylphosphonic acid (AMPA) levels. Secondary goals were to determine the association of epigenetic age acceleration with glyphosate and AMPA and develop blood DNA methylation indices to predict urinary glyphosate and AMPA levels.Methods: For 392 postmenopausal women, white blood cell DNA methylation was measured using the Illumina Infinium MethylationEPIC BeadChip array. Glyphosate and AMPA were measured in two urine samples per participant using liquid chromatography–tandem mass spectrometry. Methylation differences at the probe and regional level associated with glyphosate and AMPA levels were assessed using a resampling-based approach. Probes and regions that had an false discovery rate in of 1,000 subsamples of the study population were considered differentially methylated. Differentially methylated sites from the probe-specific analysis were combined into a methylation index. Epigenetic age acceleration from three epigenetic clocks and an epigenetic measure of pace of aging were examined for associations with glyphosate and AMPA.Results: We identified 24 CpG sites whose methylation level was associated with urinary glyphosate concentration and two associated with AMPA. Four regions, within the promoters of the MSH4, KCNA6, ABAT, and NDUFAF2/ERCC8 genes, were associated with glyphosate levels, along with an association between ESR1 promoter hypomethylation and AMPA. The methylation index accurately predicted glyphosate levels in an internal validation cohort. AMPA, but not glyphosate, was associated with greater epigenetic age acceleration.Discussion: Glyphosate and AMPA exposure were associated with DNA methylation differences that could promote the development of cancer and other diseases. Further studies are warranted to replicate our results, determine the functional impact of glyphosate- and AMPA-associated differential DNA methylation, and further explore whether DNA methylation could serve as a biomarker of glyphosate exposure. https://doi.org/10.1289/EHP10174 相似文献
97.
Pegah Kharazmi Jiannan Zheng Harvey Lui Z. Jane Wang Tim K. Lee 《Journal of medical systems》2018,42(2):33
Vascular structures of skin are important biomarkers in diagnosis and assessment of cutaneous conditions. Presence and distribution of lesional vessels are associated with specific abnormalities. Therefore, detection and localization of cutaneous vessels provide critical information towards diagnosis and stage status of diseases. However, cutaneous vessels are highly variable in shape, size, color and architecture, which complicate the detection task. Considering the large variability of these structures, conventional vessel detection techniques lack the generalizability to detect different vessel types and require separate algorithms to be designed for each type. Furthermore, such techniques are highly dependent on precise hand-crafted features which are time-consuming and computationally inefficient. As a solution, we propose a data-driven feature learning framework based on stacked sparse auto-encoders (SSAE) for comprehensive detection of cutaneous vessels. Each training image is divided into small patches of either containing or non-containing vasculature. A multilayer SSAE is designed to learn hidden features of the data in hierarchical layers in an unsupervised manner. The high-level learned features are subsequently fed into a classifier which categorizes each patch into absence or presence of vasculature and localizes vessels within the lesion. Over a test set of 3095 patches derived from 200 images, the proposed framework demonstrated superior performance of 95.4% detection accuracy over a variety of vessel patterns; outperforming other techniques by achieving the highest positive predictive value of 94.7%. The proposed Computer-Aided Diagnosis (CAD) framework can serve as a decision support system assisting dermatologists for more accurate diagnosis, especially in teledermatology applications in remote areas. 相似文献
98.
Kjell Helenius Naho Morisaki Satoshi Kusuda Prakesh S. Shah Mikael Norman Liisa Lehtonen Brian Reichman Brian A. Darlow Akihiko Noguchi Mark Adams Dirk Bassler Stellan Håkansson Tetsuya Isayama Elettra Berti Shoo K. Lee Maximo Vento Kei Lui 《Acta paediatrica (Oslo, Norway : 1992)》2020,109(7):1338-1345
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