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51.
Spastic paraplegia 46 refers to a locus mapped to chromosome 9 that accounts for a complicated autosomal-recessive form of hereditary spastic paraplegia (HSP). With next-generation sequencing in three independent families, we identified four different mutations in GBA2 (three truncating variants and one missense variant), which were found to cosegregate with the disease and were absent in controls. GBA2 encodes a microsomal nonlysosomal glucosylceramidase that catalyzes the conversion of glucosylceramide to free glucose and ceramide and the hydrolysis of bile acid 3-O-glucosides. The missense variant was also found at the homozygous state in a simplex subject in whom no residual glucocerebrosidase activity of GBA2 could be evidenced in blood cells, opening the way to a possible measurement of this enzyme activity in clinical practice. The overall phenotype was a complex HSP with mental impairment, cataract, and hypogonadism in males associated with various degrees of corpus callosum and cerebellar atrophy on brain imaging. Antisense morpholino oligonucleotides targeting the zebrafish GBA2 orthologous gene led to abnormal motor behavior and axonal shortening/branching of motoneurons that were rescued by the human wild-type mRNA but not by applying the same mRNA containing the missense mutation. This study highlights the role of ceramide metabolism in HSP pathology.  相似文献   
52.
This research provides a new way to measure error in microarray data in order to improve gene expression analysis.Microarray data contains many sources of error.In order to glean information about mRNA expression levels,the true signal must first be segregated from noise.This research focuses on the variation that can be captured at the spot level in cDNA microarray images.Variation at other levels,due to differences at the array,dye,and block levels,can be corrected for by a variety of existing normalizati...  相似文献   
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Introduction

Intraprostatic cysts are considered to be rare. Some forms may be responsible for male infertility. The authors study the various clinical aspects, with the aim of defining guidelines for the exploration and treatment of different types of intraprostatic cysts.

Materials and methods

Between 2002 and 2007, we studied 3 cases of intraprostatic cyst in 3 men aged between 32 and 39 years.

Results

The clinical presentation was primary infertility (2 cases) and pelvic pain (2 cases). Digital rectal exam revealed prostate mass in 2 cases. Spermogram results were abnormal in 2 cases. The diagnosis was confirmed by prostate ultrasound. Trans-rectal ultrasound guided needle aspiration was performed in one case with secondary recurrence. Two patients had urethroscopy showing an absence of communication between the cyst and urethral channel. Transurethral incision of the cyst was made with resection of the protruding dome. Progress was favourable in all cases with improvement of semen and dissipation of symptoms without recurrence.

Conclusion

Intraprostatic cysts are benign lesions, often of congenital origin. Imaging is an essential component of diagnosis and can sometimes guide therapeutic procedures. The treatment is not yet codified, but symptomatic and/or complicated cysts can be treated by effective and minimally invasive endoscopic methods.  相似文献   
55.

Introduction

Blunt scrotal trauma is increasingly frequent, but surgical exploration of these cases of trauma remains controversial. The objectives of this study were to assess the diagnostic value of clinical examination and ultrasound in testicular trauma and to analyse the complications of the various treatments proposed (surgical and medical treatments), in order to more clearly define the place of medical or surgical treatment in this form of trauma in young adults.

Patients and Methods

130 cases of blunt scrotal trauma were managed between 1993 and 2004. In the absence of clinical and ultrasound criteria of severity (haematocele, very large intratesticular haematoma, rupture of the tunica albuginea), medical treatment consisting of rest, anti-inflammatory drugs, and testicular support was instituted. Surgical exploration was performed when serious lesions of the testis were suspected. Scrotal ultrasound was performed in 68 patients and 46 of them underwent scrotal exploration. The sensitivity and specificity of scrotal ultrasound were determined by comparing radiological findings with definitive intraoperative findings. The immediate morbidity and long-term sequelae were analysed.

Results

The mean age of the patients was 24 years (range: 4 to 73 years). The clinical features were dominated by pain (73.8%) and scrotal swelling (89.2%). The sensitivity of testicular ultrasound was 34.7% for testicular rupture, 100% for testicular contusions, 33.3% for intratesticular hematoma and 76.9% for haematocele. Medical and surgical treatments were instituted in 29.2% and 70.7% of cases, respectively. With a mean follow-up of 8 months, chronic pain and testicular atrophy were observed in 18% and 5.5% of cases, respectively.

Conclusion

In the absence of signs of severity, medical treatment with regular surveillance remains justified. However, in the presence of doubtful clinical or ultrasound findings, surgical exploration must be performed as soon as possible  相似文献   
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超极化活化环核苷酸门控(hyperpolarization-activated cyclic-nucleotide-gated,HCN)通道参与调制心脏跳动的节律和速率。与HCN1和HCN2有所不同,慢通道HCN4可能不存在电压依赖的滞后现象。本研究采用单细胞膜片钳方法,在稳定转染hHCN4的HEK293细胞上进行电生理记录,观察hHCN4通道是否存在滞后现象,以及cAMP对其的调制作用;同时采用实时定量RT-PCR方法检测窦房结和心房组织中HCNs的表达。电压钳实验结果显示hHCN4电流(Ih)激活随着保持电位超极化的变化而向去极化方向移动。三角电位变化钳(triangular ramp)和动作电位钳的结果也显示了hHCN4的滞后现象。cAMP增加Ih电流幅度,且使电流激活向去极化方向移动,从而改变内源性hHCN4滞后行为。RT-PCR结果显示,人窦房结组织主要表达HCN4,占75%,HCN1占21%,HCN2占3%,HCN3占0.7%。以上结果提示,人窦房结组织主要表达HCN4亚型,hHCN4的Ih存在电压依赖性的滞后现象,且受cAMP调制。由此推断,hHCN4通道的滞后现象可能在窦房结起搏活动中起到了关键作用。  相似文献   
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Probiotics and Antimicrobial Proteins - Probiotics or direct-fed microbials (DFM) have proven strong potential for improving aquaculture sustainability. This study aims to evaluate the effects of...  相似文献   
60.
Efficient synthetic signal peptides for Streptomyces   总被引:1,自引:0,他引:1  
A short synthetic signal peptide (SSSP) of 26 amino acid and a long one of 35 amino acids (LSSP), having an additional ribosome binding site (RBS), were synthesized. The SSSP sequence was based on the comparison of known efficient Streptomycessignal sequences. The SSSP and the LSSP were connected to the Streptomycessp. TO1 amylase gene (amyTO1) without its signal peptide. These constructions, when cloned into Streptomycessp. TO1 and placed under the control of the ermE-up promoter of Saccharopolyspora erythrea, increased the secretion of the amylase up to six-fold when compared to the natural amyTO1 signal peptide.  相似文献   
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