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71.
Baris Turkbey Sheng Xu Jochen Kruecker Julia Locklin Yuxi Pang Marcelino Bernardo Maria J. Merino Bradford J. Wood Peter L. Choyke Peter A. Pinto 《BJU international》2011,107(1):53-57
Study Type – Diagnostic (exploratory cohort)Level of Evidence 2b What’s known on the subject? and What does the study add? Currently, systematic prostate biopsies are obtained with minimal information about their actual location. This study demonstrates that a electromagnetically tracked ultrasound probe can be used to guide biopsies into specific areas of the prostate. By registering the ultrasound to an MRI scan of the prostate, obtained prior to biopsy, it is possible to accurately map the location of biopsies. Thus, if a patient requires a repeat biopsy, or there is a question about whether a specific area of the prostate was sampled, this system can be used to more accurately guide biopsies in the future. OBJECTIVE To develop a system that documents the location of transrectal ultrasonography (TRUS)‐guided prostate biopsies by fusing them to MRI scans obtained prior to biopsy, as the actual location of prostate biopsies is rarely known. PATIENTS AND METHODS Fifty patients (median age 61) with a median prostate‐specific antigen (PSA) of 5.8 ng/ml underwent 3T endorectal coil MRI prior to biopsy. 3D TRUS images were obtained just prior to standard TRUS‐guided 12‐core sextant biopsies wherein an electromagnetic positioning device was attached to the needle guide and TRUS probe in order to track the position of each needle pass. The 3D‐TRUS image documenting the location of each biopsy was fused electronically to the T2‐weighted MRI. Each biopsy needle track was marked on the TRUS images and these were then transposed onto the MRI. Each biopsy site was classified pathologically as positive or negative for cancer and the Gleason score was determined. RESULTS The location of all (n= 605) needle biopsy tracks was successfully documented on the T2‐weighted (T2W) MRI. Among 50 patients, 20 had 56 positive cores. At the sites of biopsy, T2W signal was considered ‘positive’ for cancer (i.e. low in signal intensity) in 34 of 56 sites. CONCLUSION It is feasible to document the location of TRUS‐guided prostate biopsies on pre‐procedure MRI by fusing the pre‐procedure TRUS to an endorectal coil MRI using electromagnetic needle tracking. This procedure may be useful in documenting the location of prior biopsies, improving quality control and thereby avoiding under‐sampling of the prostate as well as directing subsequent biopsies to regions of the prostate not previously sampled. 相似文献
72.
目的探讨直肠癌远端移形黏膜COX-2及BCL-2蛋白的表达情况,判断直肠癌远端移形黏膜是否为癌前病变。方法应用高铁二胺-阿辛蓝染色检测54例直肠癌远端2cm处黏膜.将远端黏膜分为移形黏膜(TM)组及非移形黏膜(NTM)组,通过免疫组织化学染色检测TM中COX-2和BCL-2蛋白的表达.比较TM与NTM、肿瘤组织以及正常黏膜组织(20例直肠良性息肉旁肠黏膜组织)内BCL-2以及COX-2的表达的差异。结果54例直肠癌远端2cm黏膜处组织中有19例存在TM.35例为NTM。COX-2蛋白在肿瘤组织、TM、NTM、正常组织中的阳性率分别为81.5%(44/54)、21.1%(4/19)、17.1%(6/35)、10.0%(2/20);BCL-2蛋白在上述4种组织中的阳性率分别为77.8%(42/54)、21.1%(4/19)、22.9%(8/35)、5.0%(1/20)。TM内的COX-2及BCL.2蛋白的表达与肿瘤组织相比,差异有统计学意义[(0.737±0.895)比(3.519±1.998);(0.632±0.955)比(2.833±1.756),均P〈0.01];与NTM、正常肠黏膜组织相比,差异无统计学意义(均P〉0.05)。结论直肠癌远端TM内的COX-2和BCL-2蛋白的表达无特异性.TM是癌前病变的证据不足。 相似文献
73.
H.‐Y. Chiou Y.‐L. Huang M.‐C. Deng C.‐Y. Chang C.‐R. Jeng P.‐S. Tsai C. Yang V. F. Pang H.‐W. Chang 《Transboundary and Emerging Diseases》2017,64(1):157-166
New variants of porcine epidemic diarrhoea virus (PEDV), which emerged in Taiwan in late 2013, have caused a high morbidity and mortality in neonatal piglets. To investigate the molecular characteristics of the spike (S) gene of the emerging Taiwan PEDV strains for a better understanding of the genetic diversity and relationship among the Taiwan new variants and the global PEDVs, full‐length S genes of PEDVs from nine 1–7 day‐old piglets from three pig farms in the central and southern Taiwan were sequenced and analysed. The result of phylogenetic analysis of the S gene showed that all the Taiwan PEDV strains were closely related to the non‐S INDEL strains from US, Canada and China, suggesting a common ancestor for these strains. As compared with the historic PEDVs and CV777‐based vaccine strains, the nine Taiwan PEDV variants shared almost the same genetic signatures as the global non‐S INDEL strains, including a series of insertions, deletions and mutations in the amino terminal as well as identical mutations in the neutralizing epitopes of the S gene. The high similarity of the S protein among the Taiwan and the globally emerged non‐S INDEL PEDV strains suggests that the Taiwan new variants may share similar pathogenesis and immunogenicity as the global outbreak variants. The development of a novel vaccine based on the Taiwan or the global non‐S INDEL strains may be contributive to the control of the current global porcine epidemic diarrhoea outbreaks. 相似文献
74.
Analysis of loss of heterozygosity on chromosomes 10q, 11, and 16 in medulloblastomas 总被引:2,自引:0,他引:2
OBJECT: The loss of genetic material from specific chromosome loci is a common feature in the oncogenesis of tumors and is often indicative of the presence of important tumor suppressor genes at these loci. Recent molecular genetic analyses have demonstrated frequent loss of chromosomes 10q, 11, and 16 in medulloblastomas. The aim of this study was to localize the targeted deletion regions on the three aforementioned chromosomes in medulloblastomas. METHODS: Loss of heterozygosity (LOH) was examined on chromosomes 10q, 11, and 16 in a series of 22 primary and two recurrent medulloblastomas by using polymerase chain reaction-based microsatellite analysis. The DNA extracted from the tumors and corresponding normal blood samples were amplified independently in the presence of radioactively labeled microsatellite primers, resolved by denaturing gel electrophoresis and processed for autoradiography. The DNA obtained from control blood samples that displayed allelic heterozygosity at a given microsatellite locus were considered informative. Loss of heterozygosity was inferred when the allelic signal intensity of the tumor sample was reduced by at least 40%, relative to that of the constitutional control. The LOH analysis demonstrated that deletions of chromosomes 10q, 11p, and 16q are recurrent genetic events in the development of medulloblastomas. Three subchromosomal regions of loss have been identified and are localized to the deleted in malignant brain tumors 1 [DMBT1] gene site on chromosomes 10q25, 11p13-11p15.1, and 16q24.1-24.3. CONCLUSIONS: These results indicate that DMBT1 is closely associated with the oncogenesis of medulloblastomas and highlight regions of loss on chromosomes 11p and 16q for further fine mapping and cloning of candidate tumor suppressor genes that are important for the genesis of medulloblastoma. 相似文献
75.
Suzuki H Suzuki Y Aizawa M Yamanaka T Kihara M Pang H Horikoshi S Tomino Y 《Kidney international》2007,72(3):319-327
IgA nephropathy is the most common form of progressive glomerulonephritis although the pathophysiology of this nephropathy is unclear. The ddY mouse is a spontaneous animal model with variable incidence and extent of glomerular injury mimicking human IgA nephropathy. Here, we transplanted bone marrow cells from 20-week-old ddY mice with beginning or quiescent IgA nephropathy into irradiated similar ddY mice, C57Bl/6 (Th1 prone) mice, or BALB/c (Th2 prone) mice. Serum IgA/IgG complex and Th1/Th2 polarization of spleen cells was determined by enzyme-linked immunosorbent assay and confirmed by fluorescent cytometric analysis. The ddY mice with commencing IgA nephropathy demonstrated strong polarization toward Th1, while those with quiescent disease were Th2 polarized. Serum levels of IgA/IgG2a immune complex significantly correlated with the severity of the glomerular lesions. Bone marrow taken from mice with commencing IgA nephropathy conferred IgA nephropathy with Th1 polarization in recipient-quiescent mice, while transplantation from the quiescent mice ablated glomerular injury and mesangial IgA/IgG deposition in those commencing IgA disease. However, adoptive transfer of CD4(+) T cells from those whose disease began failed to induce any IgA deposition or renal injury. Our study suggests that bone marrow cells, presuming IgA producing cells, may initiate this disease. Th1 cells may be involved in the pathophysiology of the disease after glomerular IgA deposition. 相似文献
76.
Summary Bone health status of the radius in individuals with chronic stroke was evaluated using peripheral quantitative computed tomography.
Bone mineral density and cortical thickness on the affected side were compromised when compared with the unaffected side.
Muscle weakness, spasticity, and disuse were identified as contributing factors to such changes.
Introduction Following a stroke, demineralization and geometric changes occur in bone as a result of disuse and residual impairments, and
these can contribute to an increased risk of fragility fractures.
Methods This study used peripheral quantitative computed tomography (pQCT) to evaluate volumetric bone mineral density and geometry
at the midshaft radius in people living with chronic stroke. Older individuals with chronic stroke were recruited. Each subject
underwent a pQCT scan of the midshaft radius at the 30% site on both upper limbs. Muscle strength, motor function, spasticity,
and chronic disuse were also evaluated. Data from 47 subjects (19 women) were assessed.
Results A significant difference was found between the two limbs for cortical bone mineral content, cortical bone mineral density,
cortical thickness, and polar stress-strain index. There was no significant side-to-side difference in total bone area. Percent
side-to-side difference in muscle strength, spasticity, and chronic disuse were significant determinants of percent side-to-side
difference in cortical bone mineral content and cortical thickness.
Conclusions The findings suggest that following chronic stroke, endosteal resorption of the midshaft radius occurred with a preservation
of total bone area. Muscle weakness, spasticity, chronic disuse significantly contributed to demineralization and geometric
changes in the radius following chronic stroke. 相似文献
77.
Cheema B Abas H Smith B O'Sullivan A Chan M Patwardhan A Kelly J Gillin A Pang G Lloyd B Singh MF 《Journal of the American Society of Nephrology : JASN》2007,18(5):1594-1601
Skeletal muscle wasting is common and insidious in patients who receive maintenance hemodialysis treatment for the management of ESRD. The objective of this study was to determine whether 12 wk of high-intensity, progressive resistance training (PRT) administered during routine hemodialysis treatment could improve skeletal muscle quantity and quality versus usual care. Forty-nine patients (62.6 +/- 14.2 yr; 0.3 to 16.7 yr on dialysis) were recruited from the outpatient hemodialysis unit of the St. George Public Hospital (Sydney, Australia). Patients were randomized to PRT + usual care (n = 24) or usual care control only (n = 25). The PRT group performed two sets of 10 exercises at a high intensity (15 to 17/20 on the Borg Scale) using free weights, three times per week for 12 wk during routine hemodialysis treatment. Primary outcomes included thigh muscle quantity (cross-sectional area [CSA]) and quality (intramuscular lipid content via attenuation) evaluated by computed tomography scan. Secondary outcomes included muscle strength, exercise capacity, body circumference measures, proinflammatory cytokine C-reactive protein, and quality of life. There was no statistically significant difference in muscle CSA change between groups. However, there were statistically significant improvements in muscle attenuation, muscle strength, mid-thigh and mid-arm circumference, body weight, and C-reactive protein in the PRT group relative to the nonexercising control group. These findings suggest that patients with ESRD can improve skeletal muscle quality and derive other health-related adaptations solely by engaging in a 12-wk high-intensity PRT regimen during routine hemodialysis treatment sessions. Longer training durations or more sensitive analysis techniques may be required to document alterations in muscle CSA. 相似文献
78.
OBJECTIVE: To identify differential protein expression in penile tissue in a rat model of erectile dysfunction (ED) at an early stage after bilateral cavernosal nerve (CN) neurectomy, using proteomic techniques. MATERIALS AND METHODS: Twelve male adult Sprague-Dawley rats were randomly divided into two equal groups, one having bilateral CN resection and one a control group. The penises were harvested 7 days after CN resection. Total protein was separated into >1250 protein spots by two-dimensional electrophoresis using pH 3-10 nonlinear immobilized pH gradient strips. Differential expression of proteins was analysed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and database searching. RESULTS: Thirty-two proteins were significantly changed in the denervated penis, of which 25 (including nine up-regulated and 16 down-regulated) with cytoskeletal functions, and pathophysiological functions related to energy metabolism and oxidative stress, were identified. Examples include transgelin, creatine kinase B, annexin-1 and galactin-7. CONCLUSIONS: The expression of several important proteins participating in pathophysiological processes of penile tissue are changed early after bilateral CN neurectomy. These changes might give new insights into the cellular and molecular mechanisms involved in neurogenic ED development, and indicate potential therapeutic targets. 相似文献
79.
Kenny P Pang Christine G Gourin David J Terris 《Otolaryngology--head and neck surgery》2007,137(4):665-668
OBJECTIVE: Our goal was to validate the WatchPAT in the diagnosis of obstructive sleep apnea. STUDY DESIGN: We conducted a prospective, blinded, nonrandomized clinical trial. METHODS: Patients with suspected obstructive sleep apnea scheduled for an overnight level I polysomnogram were offered enrollment in a study to compare the WatchPAT (Itamar Ltd, Israel) device with polysomnography. Patients wore the WatchPAT device simultaneously while undergoing polysomnography during evaluation in the sleep lab. RESULTS: Thirty-seven patients participated in the study. They had a mean age of 50.1 years (range, 31-73 years) and mean body mass index of 34.6 kg/m(2) (range, 21.2-46.8 kg/m(2)). There was high correlation between the polysomnogram and WatchPAT apnea-hypopnea index (r = 0.9288; 95% confidence interval = 0.8579-0.9650, P < 0.0001). The lowest oxygen saturation also showed high correlation (r = 0.989; 95% confidence interval = 0.9773-0.9947, P < 0.0001). The overall polysomnogram and WatchPAT sleep times revealed a correlation of r = 0.5815 (P = 0.005). CONCLUSION: The WatchPAT showed a high correlation with the polysomnogram in apnea-hypopnea index, lowest oxygen saturation, and sleep time. SIGNIFICANCE: It's use as a reliable tool in the diagnosis of Obstructive Sleep Apnea. 相似文献
80.
BACKGROUND: Epidemiological studies showed Vit E has protective effects against prostate cancer (PCa). Interestingly, different prostate cancer cells have different sensitivity to alpha-Vit E or VES treatment. The goal of this study is to determine whether cellular Vit E bioavailability and its transport proteins are important contributing factors. METHODS: alpha-Vit E and its ester form, VES, were used to treat prostate cancer LNCaP, PC3, and DU145 cells, and their growth rates were determined by MTT assay. Cellular levels of Vit E were quantified using HPLC as the index of bioavailability. The expression levels of Vit E transport proteins were determined by real-time PCR. RESULTS: Among these PCa cells, only LNCaP cells were sensitive to 20 microM alpha-Vit E treatment, while both LNCaP and PC3 cells were sensitive to 20 microM VES treatment. Coordinately, cellular levels of alpha-Vit E and VES positively correlated to their inhibitory effects. Further study found expression levels of Vit E transport proteins, including tocopherol associated protein (TAP), scavenger receptor class B type I (SR-BI), alpha-tocopherol transfer protein (TTP), and ATP binding cassette transporter A1 (ABCA1), were different in various PCa cells, which may contribute to cellular Vit E bioavailability. This notion is further supported by the findings that overexpression or knockdown of TTP could coordinately alter cellular alpha-Vit E levels in PCa cells. CONCLUSION: Antiproliferative efficacy of alpha-Vit E is correlated with its cellular bioavailability in PCa cells. Modulating the expression of the efflux or influx transporters could sensitize the growth inhibition efficacy of Vit E in prostate cancer cells. 相似文献