牡芍合剂对骨折术后疼痛模型大鼠脊髓水平中P物质、亮氨酸脑啡肽和血管紧张素Ⅱ影响的时效性

目的研究牡芍合剂对骨折术后疼痛模型大鼠脊髓水平中P物质（Sbtance P，SP），亮氨酸脑啡肽（Leuth ine enkephalin，LEK）、血管紧张素Ⅱ（AngiotensinⅡ，AngⅡ）影响的时间依赖性，探讨牡芍合剂术后应用的最佳时间。方法：选取体重250g^-300gSPF级雄性WISTAR大鼠随机分为：正常对照组、模型组、牡芍合剂治疗组和曲马多对照组，采用Brennan术后痛模型，术后对照组、治疗组立即给药，给药后分别于1小时、24小时和48小时处死动物取脊髓，采用放射免疫学方法检测脊髓中SP、LEK、AngⅡ的含量。结果与空白组相比，其它三组大鼠脊髓中SP、LEK、AngⅡ的含量均有明显升高，与模型组相比，治疗组和对照组的SP和AngⅡ的含量有明显降低而LEK的含量明显升高，治疗组与对照组相比，各项指标没有明显差异。结论牡芍合剂能显著使大鼠脊髓中LEK含量升高，同时使SP，AII含量下降，由此初步认为，牡芍合剂可能通过激活内源性的镇痛机制而发挥作用。     

Cellular neurothekoma in an 11-year-old child

INTRODUCTION: Neurothekoma is a rare benign tumor which must be distinguished from certain malignant tumors such as fibrohistiocyte tumors or plexiform cell tumors, neurotropic melanomas and clear-cell sarcoma. CASE REPORT: An 11-year-old girl consulted for a recurrent subcutaneous tumor of the chin which had been operated 4 months earlier. The resection was incomplete. A wider revision resection successfully stopped recurrence. The histology study established the diagnosis of neurothekoma due to the presence of mitosis atypia, cellular nodules, and extension to the hypodermis. Immunohistochemistry confirmed the diagnosis. DISCUSSION: Neurothekoma is a benign tumor observed in young women, mainly on the face. It occurs as a dermal cohesive mass without infiltration of the epidermis. The typical immunohistochemical pattern enables differential diagnosis with myxoid neurothekoma, melanocytic and nervous system tumors. Surgical resection is indicated.     

Folic acid improves endothelial function in children and adolescents with type 1 diabetes

OBJECTIVE: To evaluate the effect of folate supplementation on endothelial function in children and adolescents with type 1 diabetes. STUDY DESIGN: Thirty-six subjects with type 1 diabetes age 13.6+/-2.6 years completed a randomized, double-blind, placebo-controlled crossover trial. Each subject received 8 weeks of oral folic acid (5 mg/d) and 8 weeks of placebo, with an 8-week washout period. Before and after each intervention, we assessed endothelial function by using brachial artery responses to flow (flow-mediated dilatation [FMD]) and glyceryl trinitrate, von Willebrand factor, glucose, hemoglobin A1c, total plasma homocyst(e)ine (tHcy), vitamin B(12), serum folate, and red cell folate (RCF). RESULTS: Folic acid increased FMD by 2.58 (3.1-5.7) % (95% confidence interval, 1.28-3.88), whereas placebo did not change FMD (-0.42%; 95% confidence interval, -1.67 to 0.83; P<.001). Folic acid increased serum folate by 14 nmol/L (6.2 ng/mL, P<.001) and RCF by 467.2 nmol/L (206 ng/mL, P<.001). Change in FMD was related to change in serum folate (r=0.46, P=.005) and RCF (r=0.39, P=.02). Glyceryl trinitrate responses, von Willebrand factor, tHcy, and hemoglobin A1c were not affected by the intervention. CONCLUSIONS: Short-term high-dose folic acid improves endothelial function in children and adolescents with type 1 diabetes and normal folate status independently of tHcy.     

Nucleotide sequence of the cellulase gene celF of Clostridium thermocellum

The nucleotide sequence of the celF gene of Clostridium thermocellum was determined. The open reading frame extended over 2217 bp. The encoded 739-aa polypeptide, CelF, with a M_w = 82,015, was an endoglucanase with activity against carboxymethylcellulose. The N terminus showed a typical signal peptide, and a cleavage site after Ala-27 was predicted. From residues 28 to 470, the sequence of CelF was related to the catalytic domains of type E₂ endoglucanases, with a strong homology to the endoglucanases CelZ of Clostridium stercorarium and CenB of Cellulomonas fimi. The catalytic region was followed by a 134-aa segment also present in C. stercorarium CelZ and in C. fimi CenB, and belonging to the family of non-catalytic, presumably cellulose-binding domains first identified in Bacillus subtilis endoglucanase. A 21-aa segment rich in Pro/Thr/Ser residues separated the putative cellulose-binding region from the COOH-terminal region, which contained two conserved stretches of 24 amino acids closely similar to those previously described in endoglucanases CelA, CelB, CelD, CelE, CelH and CelX, and xylanase XynZ of C. thermocellum.     

Quel avenir pour les nouvelles thérapeutiques ?

A certain number of new potential therapies for hereditary angioedema (HAE) are currently being studied. They include new inhibitors of the contact system, such as ecallantide, a kallikrein inhibitor, Icatibant, a bradykinin receptor B2 antagonist, as well as a recombinant C1-INH secreted in the milk of transgenic rabbits. Publication of the data concerning these state-of-the-art therapies could be the beginning of new therapeutic advances in the treatment of HAE and, hopefully, lead to reduction in the burden that this condition represents.     

N-乙酰-5-甲氧色胺对创伤痛的影响及作用部位分析

目的：研究N-乙酰-5-甲氧色胺对创伤痛的影响，并对其可能作用部位进行分析。方法：以大鼠截肢结合50℃热水刺激举尾作为创伤痛模型，大鼠创伤后即刻、1d、2d、3d腹腔注射不同剂量的Mel(30,60，120mg／kg）、Pt 20mg／kg、Mel Pt(10 10mg／kg)及溶媒，于创伤前及最后一次给药后20min、40min、80min、120min观察痛阈(50℃刺激举尾潜伏期)变化情况。观察创伤后3d侧脑室注射Mel(0．25、0．5、1．0mg／kg)后20min、40min、80min、120min的痛阈变化情况。结果：创伤后3d痛阈降至最低，7d恢复至正常。腹腔注射Mel(30-120mg/kg)或侧脑室注射Mel(0．25-1．0mg／kg)均剂量依赖性地增加了创伤大鼠的痛阈，且于给药后40min达高峰，持续至120min仍有效。Mel(10mg／kg)与Pt(10mg／kg)合用，能明显提高小鼠痛阈。结论：Mel对创伤痛具有良好的镇痛作用，其主要作用部位在中枢。Mel与哌替啶有明显协同镇痛效应。     

Cystathionine betasynthase and MTHFR deficiencies in adults

INTRODUCTION: Homocysteine lies at an important metabolic branch point; it may be either converted to cystathionine through the transsulfuration pathway, or methylated to form methionine. Hyperhomocysteinemia may result from hereditary defects affecting one of these reactions. STATE OF ART: Cystathionine beta synthase or 5,10-methylenetetrahydrofolate deficiency can both result in homocystinuria. Current knowledge about biochemical mechanisms leading to hyperhomocysteinemia, clinical and radiological features, pathogenesis and treatment are reviewed, focusing on late onset forms of these diseases which can be diagnosed in adulthood. CBS deficiency is characterized by lens dislocation, skeletal abnormalities, neurologic disturbances and thromboembolism. MTHFR deficiency leads to various neurological symptoms, ranging from developmental delay to encephalopathy, including motor and gait abnormalities, seizures, psychiatric manifestations and rarely strokes. The treatment of CBS deficiency depends on vitamin B6, whereas MTHFR deficiency can be efficiently treated by vitamin B12, folic acid, and betaine. PERSPECTIVES: Homocysteinemia should be measured in patients with unexplained neurological manifestations or thromboembolism.     

Homocystéinurie à révélation tardive : aspect clinique,biologique et évolutif

Homocysteinuria is a metabolic disorder with defect in genes encoding for methionine metabolism enzymes. The clinical features consist in: ophthalmic, neurological, orthopedic and vascular manifestations. It is generally diagnosed in childhood. Vascular involvements characterize adult's forms. We report one case.