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31.
The objectives of this study are to report the findings in prostatic needle biopsies positive for cancer seen in our practice with regard to the frequency of cancer detected at various sites, the cancer volume, Gleason grade, presence of perineural invasion, and others; to correlate cancer volume with Gleason grade, perineural invasion, and serum prostate-specific antigen (PSA) levels; and to correlate Gleason grade with serum PSA levels. The study was conducted at The Section of Histopathology, Department of Pathology and Microbiology, Aga Khan University Hospital, Karachi, Pakistan. All consecutive needle biopsies received from January 1, 2011 to June 30, 2012, which were positive for prostatic adenocarcinoma, were included in the study. Statistical analysis was carried out using SPSS 19.0 software package (SPSS Hong Kong Headquarters, Quarry Bay, Hong Kong). A total of 97 needle biopsies positive for carcinoma in this period were included. Prostate-specific antigen levels were available in 60.8% cases and ranged from 5.0 to 1747 ng/mL. Tumor was bilaterally present in 54.6% cases. Tumor positivity in right apex, mid, and base was 52.6%, 54.6%, and 51.5%, respectively. Tumor positivity in left apex, mid, and base was 55.7%, 63.9%, and 59.8%, respectively. Average tumor volume in right apex, mid, and base was 51.2%, 50.6%, and 49.9%, respectively. Average tumor volume in left apex, mid, and base was 49.8%, 49.1%, and 51.6%, respectively. Gleason score was 6 in 52.6% cases and 7 in 28.9% cases. Perineural invasion was positive in 46.4% cases. High-grade prostatic intraepithelial neoplasia was seen in 4 (4.1%) of 97 cases. On statistical analysis, no significant correlation was found between tumor volume and serum PSA levels. However, significant correlation was found between tumor volume and Gleason grade and between tumor volume and presence of perineural invasion. No significant correlation was found between Gleason grade and serum PSA level. To our knowledge, these are the first reported findings in prostatic needle biopsies from Pakistan. Most prostatic carcinomas in our country are still diagnosed on transurethral resection specimens, and needle biopsies are quite uncommon. Findings in needle biopsies will help in predicting adverse prognostic factors on radical prostatectomies and in planning surgery accordingly.  相似文献   
32.
Monitoring antimalarial drugs is necessary for clinical assays, human health, and routine quality control practices in pharmaceutical industries. Herein, we present the development of sensor coatings based on molecularly imprinted polymers (MIPs) combined with quartz crystal microbalance (QCM) for sensitive and selective gravimetric detection of an antimalarial drug: artemether. The MIP coatings are synthesized by using artemether as the template in a poly(methacrylic acid-co-ethylene glycol dimethacrylate) matrix. Artemether-MIP and the non-imprinted polymer (NIP) control or reference layers are deposited on 10 MHz dual-electrode QCM by spin coating (187 ± 9 nm layer thickness after optimization). The coatings are characterized by FTIR spectroscopy and atomic force microscopy that reveal marked differences among the MIP and NIP. The MIP-QCM sensor exhibits high sensitivity (0.51 Hz ppm−1) with sub-10 ppm detection and quantification limits. The MIP-QCM sensor also exhibits a 6-fold higher sensitivity compared to the NIP-QCM, and a dynamic working range of 30–100 ppm. The response time of MIP-QCM devices for a single cycle of analyte adsorption, signal saturation, and MIP regeneration is less than 2.5 min. The sensor also demonstrates selectivity factors of artemether-MIP of 2.2 and 4.1 compared to artemisinin and lumefantrine, respectively. Reversibility tests reveal less than 5% variation in sensor responses over three cycles of measurements at each tested concentration. The MIP-QCM showed lower detection limits than conventional HPLC-UV, and faster response time compared to HPLC-UV and liquid chromatography-mass spectrometry (LC-MS).

Chemical structures of the antimalarial drugs: artemisinin, artemether (a methyl ether derivative of artemisinin), and lumefantrine.  相似文献   
33.

Background and Objectives

Several clinical studies suggest that interstitial photodynamic therapy (I‐PDT) may benefit patients with locally advanced head and neck cancer (LAHNC). For I‐PDT, the therapeutic light is delivered through optical fibers inserted into the target tumor. The complex anatomy of the head and neck requires careful planning of fiber insertions. Often the fibers' location and tumor optical properties may vary from the original plan therefore pretreatment planning needs near real‐time updating to account for any changes. The purpose of this work was to develop a finite element analysis (FEA) approach for near real‐time simulation of light propagation in LAHNC.

Methods

Our previously developed FEA for modeling light propagation in skin tissue was modified to simulate light propagation from interstitial optical fibers. The modified model was validated by comparing the calculations with measurements in a phantom mimicking tumor optical properties. We investigated the impact of mesh element size and growth rate on the computation time, and defined optimal settings for the FEA. We demonstrated how the optimized FEA can be used for simulating light propagation in two cases of LAHNC amenable to I‐PDT, as proof‐of‐concept.

Results

The modified FEA was in agreement with the measurements (P = 0.0271). The optimal maximum mesh size and growth rate were 0.005–0.02 m and 2–2.5 m/m, respectively. Using these settings the computation time for simulating light propagation in LAHNC was reduced from 25.9 to 3.7 minutes in one case, and 10.1 to 4 minutes in another case. There were minor differences (1.62%, 1.13%) between the radiant exposures calculated with either mesh in both cases.

Conclusions

Our FEA approach can be used to model light propagation from diffused optical fibers in complex heterogeneous geometries representing LAHNC. There is a range of maximum element size (MES) and maximum element growth rate (MEGR) that can be used to minimize the computation time of the FEA to 4 minutes. Lasers Surg. Med. 47:60–67, 2015. © 2015 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.  相似文献   
34.
We report our experience in treating victims of the recent earthquake disaster in Pakistan. Our experience was based on two humanitarian missions to Islamabad: one in October 2005, 10 days after the earthquake, and the second in January 2006. The mission consisted of a team of orthopaedic surgeons and a second team of plastic surgeons. The orthopaedic team bought all the equipment for application of Ilizarov external fixators. We treated patients who had already received basic treatment in the region of the disaster and subsequently had been evacuated to Islamabad. During the first visit, we treated 12 injured limbs in 11 patients. Four of these patients were children. All cases consisted of complex multifragmentary fractures associated with severe crush injuries. All fractures involved the tibia, which were treated with Ilizarov external fixators. Nine fractures were type 3b open injuries. Eight were infected requiring debridement of infected bone and acute shortening. During a second visit, we reviewed all patients treated during our first mission. In addition, we treated 13 new patients with complex non-unions. Eight of these patients were deemed to be infected. All patients had previous treatment with monolateral fixators as well as soft tissue coverage procedures, except one patient who had had an IEF applied by another team. All these patients had revision surgery with circular frames. All patients from both groups were allowed to fully weight-bear post-operatively, after a short period of elevation to allow the flaps to take. Overall, all fractures united except one case who eventually had an amputation. Four patients had a corticotomy and lengthening, and three of them had a successful restoration of limb length. The fourth patient was the one with the eventual amputation.  相似文献   
35.
Hyperuricemia (HUA), a disease due to an elevation of body uric acid level and responsible for various diseases such as gout, cardiovascular disorders, and renal failure, is a major ground debate for the medical science these days. Considering the risk factors linked with allopathic drugs for the treatment of this disease, the debate has now become a special issue. Previously, we critically discussed the role of dietary polyphenols in the treatment of HUA. Besides dietary food plants, many researchers figure out the tremendous effects of medicinal plants‐derived phytochemicals against HUA. Keeping in mind all these aspects, we reviewed all possible managerial studies related to HUA through medicinal plants (isolated compounds). In the current review article, we comprehensively discussed various bioactive compounds, chemical structures, and structure–activity relationship with responsible key enzyme xanthine oxidase.  相似文献   
36.
BackgroundUpper gastrointestinal (UGI) bleed is a common surgical disease in sub-Saharan Africa where there is often a lack of diagnostic and interventional adjuncts such as endoscopy. This study sought to characterize the role of endoscopy in management of acute UGI bleeding.Materials and MethodsThis is a prospective observational analysis of adults presenting with an UGI bleed to a tertiary center in Lilongwe, Malawi, over two years. Patients were classified as having no endoscopy, diagnostic endoscopy, or endoscopy with variceal banding. Bivariate, survival analysis, and logistic regression analyses were used to compare intervention cohorts.Results293 patients were included with 49 patients (16.7%) receiving endoscopy with banding, 65 (22.2%) patients receiving diagnostic endoscopy only, and 179 (61.1%) receiving no endoscopy. Upon survival analysis comparing to the no endoscopy group, cox hazard modelling showed an adjusted hazard ratio over 30 days of 0.12 (95% CI 0.02, 0.88, p=0.038) for the endoscopic banding group and a hazard ratio of 0.39 (95% CI 0.13, 1.16, p=0.090) for the diagnostic endoscopy only group. Physical exam findings consistent with cirrhosis and decreasing age were independent predictors of an endoscopic diagnosis of variceal bleeding.ConclusionEsophagogastric varices are a common cause of UGI bleeding in sub-Saharan Africa and can be predicted with age and physical exam findings. Endoscopy with variceal banding has a survival benefit for patients presenting with acute UGI bleed even with relatively low utilization. Appropriately triaging patients with likely variceal bleeding and improving endoscopy capacity would likely have a significant impact on mortality.  相似文献   
37.
A child with a complicated medical history that included asplenia acquired an infection with Babesia microti in the summer of 2013 and had not travelled outside of Manitoba. Although the clinical findings were subtle, astute laboratory work helped to reach a preliminary identification of Babesia species, while reference laboratory testing confirmed the diagnosis. Blacklegged ticks (Ixodes scapularis) are known to transmit Borrelia burgdorferi and Anaplasma phagocytophilum in the province; however, the present case represents the first known instance of tick-borne B microti, both in Manitoba and in Canada. The expanding territory of the blacklegged tick increases the relevance of this emerging infection. Clinicians, laboratory medical practitioners and public health officials should be aware of B microti as a potential locally acquired infection in Canada.  相似文献   
38.
39.
We already developed an ex vivo liver‐kidney model perfused for 6 h in which the kidney acted as a homeostatic organ to improve the circuit milieu compared to liver alone. In the current study, we extended the multiorgan perfusions to 24 h to evaluate the results and eventual pitfalls manifesting with longer durations. Five livers and kidneys were harvested from female pigs and perfused over 24 h. The extracorporeal circuit included a centrifugal pump, heat exchanger, and oxygenator. The primary end point of the study was the evaluation of the organ functions as gathered from biochemical and acid‐base parameters. In the combined liver‐kidney circuit, the organs survived and maintained an acceptable homeostasis for different lengths of time, longer for the liver (up to 19–23 h of perfusions) than the kidney (9–13 h of perfusions). Furthermore, glucose and creatinine values decreased significantly over time (from the 5th and 9th hour of perfusion onward). The addition of a kidney to the perfusion circuit improved the biochemical environment by removing excess products from ongoing metabolic processes. The consequence is a more physiological milieu that could improve results from future experimental studies. However, it is likely that long perfusions require some nutritional support over the hours to maintain the organ's vitality and functionality throughout the experiments.  相似文献   
40.
The molecular basis of coronary artery disease (CAD) has been widely studied in the western world but there is no published work on the Malaysian population. This study looked at the global gene expression profiling of the peripheral blood of patients with CAD from the 3 main ethnic groups in Malaysia. Male subjects selected were based on angiographically confirmed CAD (≥50% stenosis) and normal control subjects (0% stenosis) with age range of 55.6±5.3 and 51.0±5.5years, respectively. The global gene expression of 12 angiographically documented CAD patients and 11 matched control subjects were performed. The combined group samples identified 6 up regulated differential expression (DE) genes (GHRL, LTA, CBS, HP, ITGA2B, and OLR1) and 12 down regulated DE genes (IL18R1, ITGA2B, IL18RAP, HP, OLR1, SOD2 ITGB3, IL1B, MMP9, PLA2G7, UTS2, and CBS) to be involved in CAD at the fold change of 1.3 with fault discovery rate (FDR) of 1%. Three genes, MMP9, IL1B, and SOD2 were down regulated in all the 3 ethnic groups making them potential biomarker candidates for CAD across all three ethnicities. Further verification in a cohort study is needed.  相似文献   
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