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41.
Candidate gene analysis of SPARCL1 gene in patients with multiple sclerosis   总被引:1,自引:0,他引:1  
Recently, proteomic analysis in cerebrospinal fluid (CSF) from patients with MS identified four proteins which are present in MS but not in normal human CSF, including SPARCL1, an extracellular matrix-associated protein member of the SPARC family. One hundred eighty-six patients with MS and 185 age-matched controls were genotyped for A/G single nucleotide polymorphism (SNP) in exon 1 (rs1049539), C/G SNP in exon 4 (rs1049544), resulting in a substitution of an aspartate with an histidine, and A/G substitution in the exon 5 (rs1130643), leading to the substitution of alanine with threonine. No significant differences in either allelic or genotypic frequency of the three SNPs were found (P>0.05), even in stratifying MS patients according to the course of the disease. Stratifying according to gender, a trend towards a decreased frequency of the C/C genotype of the rs1049544 was observed in male patients as compared with male controls (30.2% versus 44.0%; P=0.217). Despite proteomic studies in CSF from MS patients suggested an important role for SPARCL1 in the development of the disease, SPARCL1 gene does not appear to act as susceptibility factor for MS in the population investigated here. However, the frequency of the C/C genotype of rs1049544 was decreased in male patients, possibly conferring a lower risk of developing MS in male population. Further studies are needed to clarify this issue.  相似文献   
42.
The mechanisms responsible for changes in brain function during normal sleep are poorly understood. In this study, we aimed to investigate the effects of sleep on human corticospinal excitability by estimating resting motor threshold (RMT), and latency and amplitude of motor-evoked potentials (MEPs) after delivering transcranial magnetic stimulation (TMS) in ten healthy subjects. We also aimed to study short-interval intracortical inhibition (SICI) during sleep with paired-pulse TMS (pp-TMS). Ten healthy volunteers were studied. They were monitored immediately before, during and after a 3-h sleep (from 1 p.m. to 4 p.m., immediately after the mid-day meal). EEG was continuously recorded during sleep and the various sleep stages were identified off line. Every 10 min, subjects received ten single stimuli (to estimate RMT, MEP latency and amplitude) and six paired stimuli (to estimate SICI). MEP amplitude decreased and latency and RMT increased during the various sleep stages and returned to baseline values on awakening. Post hoc comparisons showed a significant difference in pp-TMS MEP amplitudes between the sleep and all the other conditions. The changes in TMS evoked variables during the different sleep stages indicate that during nonrapid eye movement sleep, cortical pyramidal neuron excitability (as measured by RMT, MEP latency and amplitude) progressively diminishes and the efficiency of the intracortical GABA-ergic network (as assessed by three pp-TMS) increases. On awakening, these sleep-induced changes in corticospinal excitability return rapidly to values observed during wakefulness.  相似文献   
43.
The proliferation marker pKi-67 ('Ki-67 antigen') is commonly used in clinical and research pathology to detect proliferating cells, as it is only expressed during cell-cycle progression. Despite the fact that this antigen has been known for nearly two decades, there is still no adequate understanding of its function. This study has therefore identified proteins that interact with pKi-67, using a yeast two-hybrid system. A mammalian two-hybrid system and immunoprecipitation studies were used to verify these interactions. Among other cell-cycle regulatory proteins, two binding partners associated with the small GTPase Ran were identified. In addition, DNA-structural and nucleolus-associated proteins binding to pKi-67 were found. Moreover, it was demonstrated that the N-terminal domain of pKi-67 is capable of self-binding to its own repeat region encoded by exon 13. Since RanBP, a protein involved in the transport of macromolecules over the nuclear lamina, was found to be a binding partner, a possible effect of pKi-67 on the localization of cell-cycle regulatory proteins was proposed. To test this hypothesis, a tetracycline-responsive gene expression system was used to induce the pKi-67 fragments previously used for the two-hybrid screens in HeLa cells. Subsequent immunostaining revealed the translocation of cyclin B1 from cytoplasm to nucleoli in response to this expression. It is suggested that pKi-67 is a Ran-associated protein with a role in the disintegration and reformation of the nucleolus and thereby in entry into and exit from the M-phase.  相似文献   
44.
BackgroundWhilst there is a trend away from aggressive nonorgan sparing surgical treatments for malignant penile disease, a variety of penile preservation options exist but functional outcomes and patient reported outcomes (PROs) in this area are poorly reported to date.AimThe aim of this study is to report functional outcomes and PROs of total glans resurfacing (TGR) in a consecutive series of patients with lichen sclerosis (LS) or localized penile cancer (PC).MethodsFrom 2004 to 2018 a consecutive series of patients underwent TGR for the management of LS or localized PC in a tertiary referral network. Patient clinical records and operative notes were retrospectively reviewed. Statistical analysis was conducted with Stata 12.OutcomesUrinary and sexual outcomes were recorded utilizing both the International Index of Erectile Function (IIEF) and International Prostate Symptom Score (IPSS) validated questionnaires while PROs were extrapolated from a 5-item “ad hoc” telephone questionnaire administered at 1 year post procedure.Results37 consecutive patients were enrolled. Histology results demonstrated LS in 16 patients, with the remaining 21 having a diagnosis of PC. The most common reasons for patient presentation were local pain (32.4%), pruritus (37.8%) and bleeding (29.7%). Median follow-up was 22 (IQR 13–77) months. Median age was 62 (IQR 55–68).Neither of the questionnaires assessing urinary and sexual function showed any significant deterioration after surgery. Glans sensitivity was fully maintained in 89.2% of cases. 94.5% of patients reported to be fully satisfied with the aesthetic appearance of the penis and would consider undergoing the same procedure again if necessary. 91.9% of patients would recommend the same procedure to someone else. An overall improvement of the quality of life was reported by 86.4% of patients.Clinical ImplicationsTGR should be considered a treatment of choice for selected cases of benign or malignant penile lesionsStrengths and LimitationsOur study has some limitations, the first being its retrospective nature. Furthermore, despite being one of the largest series to date, follow-up duration is somewhat limited and a control group is lacking.ConclusionTGR represents an excellent surgical option ensuring satisfactory voiding and sexual function, as well as cosmesis for selected cases of penile lesions.M. Preto, M. Falcone, G. Blecher, et al. Functional and Patient Reported Outcomes Following Total Glans Resurfacing. J Sex Med 2021;18:1099–1103.  相似文献   
45.
Primary and recurrent cytomegalovirus (CMV) infections frequently cause CMV colitis in immunocompromised as well as inflammatory bowel disease (IBD) patients. Additionally, colitis occasionally occurs upon primary CMV infection in patients who are apparently immunocompetent. In both cases, the underlying pathophysiologic mechanisms are largely elusive - in part due to the lack of adequate access to specimens. We employed the mouse cytomegalovirus (MCMV) model to assess the association between CMV and colitis. During acute primary MCMV infection of immunocompetent mice, the gut microbial composition was affected as manifested by an altered ratio of the Firmicutes to Bacteroidetes phyla. Interestingly, these microbial changes coincided with high-titer MCMV replication in the colon, crypt hyperplasia, increased colonic pro-inflammatory cytokine levels, and a transient increase in the expression of the antimicrobial protein Regenerating islet-derived protein 3 gamma (Reg3γ). Further analyses revealed that murine and human intestinal epithelial cell lines, as well as primary intestinal crypt cells and organoids represent direct targets of CMV infection causing increased cell death. Accordingly, in vivo MCMV infection disrupted the intestinal epithelial barrier and increased apoptosis of intestinal epithelial cells. In summary, our data show that CMV transiently induces colitis in immunocompetent hosts by altering the intestinal homeostasis.  相似文献   
46.
Bony free flap reconstruction of the facial skeleton remains a challenging area of reconstructive surgery. Despite technological advances that have aided planning and execution of these procedures, surgical inaccuracy is not insignificant. One source of error that has not been wholly addressed is that attributable to a human operator. In this study, we investigate the feasibility and accuracy of performing osteotomies robotically in pre‐programmed fashion for fibula free flap mandible reconstruction as a method to reduce inaccuracies related to human error. A mandibular defect and corresponding free fibula flap reconstruction requiring six osteotomies were designed on a CAD platform. A methodology was developed to translate this virtual surgical plan data to a robot (KUKA, Augsburgs, Germany), which then executed osteotomies on three‐dimensional (3D) printed fibula flaps with the aid of dynamic stereotactic navigation. Using high‐resolution computed tomography, the osteotomized segments were compared to the virtually planned segments in order to measure linear and angular accuracy. A total of 18 robotic osteotomies were performed on three 3D printed fibulas. Compared to the virtual preoperative plan, the average linear variation of the osteotomized segments was 1.3 ± 0.4 mm, and the average angular variation was 4.2 ± 1.7°. This preclinical study demonstrates the feasibility of pre‐programmed robotic osteotomies for free fibula flap mandible reconstruction. Preliminarily, this method exhibits high degrees of linear and angular accuracy, and may be of utility in the development of techniques to further improve surgical accuracy. © 2015 Wiley Periodicals, Inc. Microsurgery 36:246–249, 2016.  相似文献   
47.
Investigators often study rats by microCT to investigate the pathogenesis and treatment of skeletal disorders in humans. However, microCT measurements provide information only on bone mineral content and not the solid matrix. CT scans are often carried out on cancellous bone, which contains a significant volume of marrow cells, stroma, water, and fat, and thus the apparent bone mineral density (BMD) does not reflect the mineral density within the matrix, where the mineral crystals are localized. Water- and fat-suppressed solid-state proton projection imaging (WASPI) was utilized in this study to image the solid matrix content (collagen, tightly bound water, and other immobile molecules) of rat femur specimens, and meet the challenges of small sample size and demanding submillimeter resolution. A method is introduced to recover the central region of k-space, which is always lost in the receiver dead time when free induction decays (FIDs) are acquired. With this approach, points near the k-space origin are sampled under a small number of radial projections at reduced gradient strength. The typical scan time for the current WASPI experiments was 2 hr. Proton solid-matrix images of rat femurs with 0.4-mm resolution and 12-mm field of view (FOV) were obtained. This method provides a noninvasive means of studying bone matrix in small animals.  相似文献   
48.
Contrast-enhanced US of hepatocellular carcinoma   总被引:7,自引:0,他引:7  
PURPOSE: To evaluate the capabilities of contrast-enhanced ultrasound (CEUS) in the characterization of hepatocarcinoma (HCC) in terms of accuracy as compared to spiral CT and diagnostic gain as compared to conventional and Doppler US. MATERIALS AND METHODS: Forty-three patients with viral hepatopathy or cirrhosis diagnosed with HCC (6 histologically and 37 cytologically proven) were retrospectively studied. Between January 2002 and May 2003, all patients were evaluated with CEUS after detection of at least one suspicious nodule on US. CEUS features of HCCs were retrospectively compared with those on conventional and Doppler US, and spiral CT. RESULTS: HCCs varied between 1.2 cm and 18 cm in diameter; 14/43 were small' (< or = 2 cm). In 18/43 patients, HCC was multifocal. Doppler US revealed 24/43 hypervascular nodules. On CEUS, 37/43 (86%) showed contrast enhancement in the arterial phase, 13/37 (35%) with negative colour and power Doppler US examination; in 6/37 (16%) contrast enhancement in the arterial phase was not visible on spiral CT. On CEUS, 6/43 hypovascular HCCs were characterized as malignant in the sinusoidal phase. On CEUS, the sinusoidal phase revealed additional nodules not visible on baseline US in 3/18 multifocal HCCs. CONCLUSIONS: CEUS diagnosis of HCC in cirrhotic liver is possible with a combination of the arterial phase, which shows tumoral hypervascularity in the microcirculation, and the sinusoidal phase, which allows to confirm the malignancy of the nodule.  相似文献   
49.
Lesions composed of Pacinian corpuscles or showing Pacinian corpuscle differentiation have usually been described in relation to benign tumours of the peripheral nervous system or reactive hyperplastic processes. On the other hand, mature Pacinian corpuscles have occasionally been detected as part of intraspinal lumbosacral lipomas, a rare developmental anomaly usually associated with spina bifida. A lesion of the cauda equina composed of numerous mature Pacinian corpuscles and nerve fascicles embedded in adipose tissue in association with spina bifida occulta is described in a 5-month-old male with a sacral red papula. Magnetic resonance imaging (MRI) revealed a cord-like mass in the region of the cauda equina, presumably connected to the subcutis. With the exception of a low lying, tethered spinal cord, there was no neurological deficit and the range of motor development was normal. In March 2005, at 17 months, surgery was carried out. A cord of yellow tissue was found running from the subcutis through the bone defect into the lumbosacral spinal canal. Intradurally, it ran parallel to the cauda equina, terminating at the conus medullaris. Fifteen months after the surgery the development of the child was normal. Only two similar cases have been reported so far. Due to their occurrence in the sacrococcygeal region and association with developmental anomalies, they have been regarded as malformations and the term Pacinioma has been suggested. Our case with clusters of Pacinian corpuscles may represent a rare variant of complex intraspinal lumbosacral lipomas, closely related to Paciniomas reported by Bale.  相似文献   
50.
目的 近年来,医学、外科类文献有向循证医学方向发展的趋势.本研究旨在检测已发表的整形外科类文章的证据水平.方法 回顾性分析<整形再造外科杂志(Plastic and Reconstructive Surgery,PRS)><整形外科年鉴(Annals of Plastic Surgery,Annals)><整形再造与美容外科杂志(Journal of Plastic,Reconstructive,and Aesthetic Surgery,JPRAS)><美国美容外科杂志(American Journal of Aesthetic Surgery,Aesthetic)>4本主要的整形外科类杂志2009年1~12月刊载论文利用证据的水平.结果 在1759篇文献中,共有726篇(41%)纳入本研究标准(排除动物实验、尸体研究、基础医学、文献复习、继续教育和信函等方面文献).将选中的文献根据其证据水平进行分级(Ⅰ~Ⅳ级;Ⅰ级,证据水平最高,如随机对照研究;Ⅳ级,证据水平最低,如病例报告).4本杂志的平均证据水平分别为:PRS=3.05,Aesthetic=3.11,JPRAS=3.35,Annals=3.31.4本杂志的平均证据水平,除了JPRAS与Aesthetic的差异无统计学意义外,余者差异均有统计学意义(P<0.05).本研究纳入标准的文献,只有2.2%的证据水平为Ⅰ级.结论 4本杂志的平均证据水平为3.2(Ⅲ级水平).为了使整形外科专业加入到高水平循证医学行列,我们应当在今后的工作中着重强调随机对照研究的应用.  相似文献   
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