Inactivation of human synovial fluid phospholipase A2 by the marine natural product, manoalide

The marine natural product, manoalide (MLD), was investigated to determine if this drug inhibited purified human synovial fluid phospholipase A2 (HSF-PLA2). Utilizing classical Michaelis-Menten kinetics, apparent Km and Vmax values for HSF-PLA2 of 1.34 mM and 0.47 mumol [3H]palmitic acid released/min/mg protein were obtained using dipalmitoylphosphatidylcholine (DPPC) as the substrate, and 38.0 microM and 18.8 mumol [3H]arachidonic acid released/min/mg protein with Escherichia coli as a natural substrate. These kinetic parameters were utilized subsequently to evaluate the inhibitory effects of manoalide on HSF-PLA2. Inhibition of HSF-PLA2 by MLD was concentration and time dependent with IC50 values of 0.2 and 0.02 microM for DPPC and E. coli respectively. Dialysis studies and examination of DPPC or E. coli hydrolysis versus enzyme concentration indicate that MLD is an irreversible inhibitor of HSF-PLA2. Substrate specificity was also examined in the absence and presence of MLD using dipalmitoylphosphatidylethanolamine (DPPE) as a substrate. MLD inhibited the hydrolysis of DPPE (greater than 90% inhibition at 2 microM), and preliminary results indicate that DPPC was more readily hydrolyzed than DPPE under the substrate conditions of the assay. While the cellular source of secreted HSF-PLA2 is unknown, these studies indicate that MLD can inactivate secreted phospholipase A2 isolated from patients with inflammatory joint disease.     

Influence of Age and Sex on the Position of the Conus Medullaris and Tuffier's Line in Adults

Background: The purpose of this study was to analyze the position of the conus medullaris and Tuffier's line in the same patient population, to correlate this position with age and sex, and to determine an objective guide for the selection of a safe intervertebral space during spinal block.

Methods: Magnetic resonance imaging studies of the lumbar spine were reviewed in 690 consecutive patients. The study population consisted of patients older than 20 yr who had been referred for imaging to assess possible causes of low back pain. The position of the conus medullaris was defined as the most distal point of the cord that could be visualized on the sagittal sequence. A line perpendicular to the long axis of the cord was extended to the adjacent vertebra. In the lumbar plain films, the Tuffier's line was defined by drawing a horizontal line across the highest points of the iliac crests. Each vertebral body and intervertebral space was divided into four segments: upper, middle, and lower thirds of a vertebral body, and the intervertebral space. Each segment of a vertebral body or intervertebral space that the lines crossed was identified and recorded. The positions, stratified by decade of age, were compared using analysis of variance. The Tukey test was used for post hoc comparisons. Comparisons between sex were performed with the unpaired t test.

Results: The conus medullaris and Tuffier's line (median [range]) were positioned at L1-lower (T12-upper-L3-upper) and L4L5 (L3L4-L5S1), respectively. The distance between the conus medullaris and Tuffier's line (mean +/- SD [range]) was 12.6 +/- 1.9 [7-18] segments, which corresponded to the height of approximately three vertebral bodies and intervertebral spaces. In no case did Tuffier's line overlap with the conus medullaris. The distance in segments between the conus medullaris and Tuffier's line was shorter with increased age (P < 0.001). The position of the conus medullaris and Tuffier's line was lower in female patients than in male patients (P < 0.001) and higher in patients with sacralization than in those with lumbarization or without transitional vertebra (P < 0.001). The in-between distances were not significantly different regardless of sex or presence of transitional vertebra.     

金黄色葡萄球菌儿童株耐药性分析

目的 了解儿童中金黄色葡萄球菌所致疾病的分布及其对常用抗生素的敏感情况。方法 收集连续12个月的临床致病株，根据菌落形态、革兰染色特点和乳胶凝集实验对金黄色葡萄球菌进行初步筛选，用细菌自动鉴定系统Vitek GPI卡和GPS-101卡进行菌株鉴定和药敏试验。结果 分离到金黄色葡萄球菌145株，其中来自呼吸道感染患儿痰或咽拭子培养109株，占75．17％，来自血培养16株，占11．03％，来自脓液、阴道分泌物培养分别占6．21％和5．51％。药敏试验显示92．4l％的菌株产生β-内酰胺酶，96．55％的菌株对青霉素耐药，但耐苯唑西林的仅占6．21％。99．31％和100％的菌株分别对利福平和万古霉素敏感，对环丙沙星、阿莫西林／棒酸、头孢唑林、复方新诺明、庆大霉素和林可霉素的敏感率分别为95．86％、93．10％、92．41％、86．21％、84．83％和80．69％，37．93％的菌株对红霉素耐药。结论金黄色葡萄球菌常引起儿童呼吸道感染，对苯唑西林的耐药率低．该药仍是治疗小儿会黄色葡萄球菌感染的有效药物。     

寒冷干燥地区平时火器伤的早期处理

目的　探讨寒冷干燥地区平时火器伤伤情特点与早期救治方法。方法　对 1991年 1月— 2 0 0 2年 12月间 40例火器伤病人的临床救治进行回顾分析。结果　 2 4例枪伤中 ,2 0例一期缝合伤口 ,均一期愈合 ,另外 4例只清创未一期缝合的伤口 ,3例愈合 ,1例感染 ;4例骨折内固定均愈合良好 ,无骨髓炎发生。 16例炸伤病人局部软组织损伤及污染比枪弹伤重 ,14例一期缝合伤口中 ,10例一期愈合 ,4例感染 ,骨折内固定 2例 ,均愈合良好 ,无骨髓炎发生。结论　寒冷干燥地区火器伤早期伤道清创时限可适当延长 ,在平时火器伤的救治中 ,对软组织条件较好的创面 ,早期清创后可一期闭合伤口和骨折内固定 ,这样可减少感染和伤残 ,促进康复     

Histological comparison of implanted cadaveric and porcine dermal matrix grafts.

OBJECTIVES: Histological comparison of human-based (AlloDerm) and porcine-based (ENDURAGen) dermal matrices regarding tissue incorporation and neovascularization as potential soft tissue augmentation materials. STUDY DESIGN: In vivo, rat model. METHODS: Subcutaneous implantation of 1-mm thick, 1 cm x 1 cm pieces of AlloDerm, ENDURAGen, and meshed ENDURAGen was performed in 24 Sprague Dawley rats. Implant materials were harvested at 4 (n = 12) and 8 weeks (n = 12). Histological quantification of soft tissue ingrowth and microvascular density was performed following hematoxylin-eosin staining and CD34 immunohistochemistry, respectively. RESULTS: AlloDerm showed significantly greater soft tissue ingrowth and microvascular density compared with both ENDURAGen and meshed ENDURAGen at 4 and 8 weeks (P < 0.001). CONCLUSIONS: Although these results may differ in human host tissues, AlloDerm seems to be a more suitable dermal matrix implant than ENDURAGen for cases in which tissue incorporation and neovascularization are sought for the optimal outcome based on this animal model.     

Anatomic and spiral computed tomographic study of the genial tubercles for genioglossus advancement.

OBJECTIVE: To measure and compare Chinese mandibular genial tubercles measured anatomically and with computed tomography (CT). STUDY DESIGN AND SETTING: Spiral CT scans were taken of 40 adult human skulls; the superior genial spines were measured using anatomic and CT methods. RESULTS: The height and width of the superior genial spines, mandible thickness, and distance from the menton to the inferior and superior margins of the superior genial spines were 5.82 +/- 0.71, 6.98 +/- 1.35, 11.95 +/- 1.59, 11.08 +/- 2.05, and 16.91 +/- 2.30 mm from anatomic measurements and 6.17 +/- 0.71, 7.01 +/- 1.13, 12.19 +/- 1.64, 10.41 +/- 1.55, and 15.73 +/- 2.12 mm using spiral CT, respectively. The anatomic and CT measurements were correlated. CONCLUSION: Spiral CT of the genial tubercles can help locate the osteotomy in genioglossus advancement. SIGNIFICANCE: This study acquired reference data on Chinese genial tubercles demonstrating that CT measurements of the genial tubercles reflect their anatomy, which should allow accurately locate the osteotomy.     

Surgical treatment of pseudosyndactyly of children with epidermolysis bullosa: a case report.

Recessive dystrophic epidermolysis bullosa (RDEB) is an uncommon and severe disorder characterised by trauma-induced blisters, intractable skin ulcers, scarring, milia, and nail dystrophy. We report the good result of both surgical release of fingers allowing spontaneous epithelisation without skin grafting and post-operative meticulous skin care without splinting, followed-up for one year.     

导数—分光光度法测定小儿胺散的含量

Sulfaguanidine (Ⅰ) and sulfadimidine (Ⅱ) in infantile co-sulfadimidine powders were determined using derivative-spectrophotometry. Ⅰ and Ⅱ were extracted with 10 ml dilute HCl, and added 0.1 mol/L HC1 to 100 ml. Ⅰ was analyzed with spectrophotometry at 220 nm. Ⅱ was analyzed with derivative-spectrophotometry at 321, 324 nm. Recoveries of Ⅰ and Ⅱ were 100.2±0.33% and 100.3±0.55% respectivly.     

Ion channel expression by white matter glia: I. Type 2 astrocytes and oligodendrocytes

White matter is a compact structure consisting primarily of neuronal axons and glial cells. As in other parts of the nervous system, the function of glial cells in white matter is poorly understood. We have explored the electrophysiological properties of two types of glial cells found predominantly in white matter: type 2 astrocytes and oligodendrocytes. Whole-cells and single-channel patch-clamp techniques were used to study these cell types in postnatal rat optic nerve cultures prepared according to the procedures of Raff et al. (Nature, 303:390-396, 1983b). Type 2 astrocytes in culture exhibit a "neuronal" channel phenotype, expressing at least six distinct ion channel types. With whole-cell recording we observed three inward currents: a voltage-sensitive sodium current qualitatively similar to that found in neurons and both transient and sustained calcium currents. In addition, type 2 astrocytes had two components of outward current: a delayed potassium current which activated at 0 mV and an inactivating calcium-dependent potassium current which activated at -30 mV. Type 2 astrocytes in culture could be induced to fire single regenerative potentials in response to injections of depolarizing current. Single-channel recording demonstrated the presence of an outwardly rectifying chloride channel in both type 2 astrocytes and oligodendrocytes, but this channel could only be observed in excised patches. Oligodendrocytes expressed only one other current: an inwardly rectifying potassium current that is mediated by 30- and 120-pS channels. Because these channels preferentially conduct potassium from outside to inside the cell, and because they are open at the resting potential of the cell, they would be appropriate for removing potassium from the extracellular space; thus it is proposed that oligodendrocytes, besides myelinating axons, play an important role in potassium regulation in white matter. The conductances present in oligodendrocytes suggest a "modulated Boyle and Conway mechanism" of potassium accumulation.