Ganglioside expression in tissues of mice lacking beta2-microglobulin

This study presents a comparative analysis of gangliosides from lymphoid (spleen and thymus) and other (brain, liver, lungs and muscle) tissues of C57BL/6 mice lacking the gene for beta2-microglobulin (beta2M), a constitutive component of the MHC class I molecule. Ganglioside fractions in the tissues of mice homozygous (beta2M-/-) and heterozygous (beta2M-/+) for the gene deletion were determined by high performance thin-layer chromatography (HPTLC), followed by immunostaining with specific polyclonal antibodies. Ubiquitous gangliosides GM3(Neu5Ac) and GM3(Neu5Gc) were the dominant gangliosides in the lungs of the control beta2M-/+ mice, whereas the homozygous knockout mice had substantially decreased expression of these structures. The lungs of the beta2M-/- mice also had reduced expression of T-lymphocyte-specific GM1b-type gangliosides (GM1b and GalNAc-GM1b). beta2M-deficient mice also had more GM1a and GD1a gangliosides in the liver, and several neolacto-series gangliosides were increased in the brain and lungs. This study provides in vivo evidence that the beta2M molecule can influence the acquisition of a distinct ganglioside assembly in different mouse organs, implicating its non-immunological functions.     

Major phospholipids and phosphatidylcholine synthesis in adult Schistosoma mansoni

The major phospholipids present in the phospholipid extract of Schistosoma mansoni were phosphatidylcholine (28%), phosphatidylethanolamine (25%), phosphatidylserine (15%) and phosphatidylglycerol (8%). The synthesis of phosphatidylcholine in S. mansoni adults occurred by the choline to phosphatidylcholine or Kennedy pathway. Incorporation of CDPcholine and choline into the phosphatidylcholine of worm slices appeared linear over time with no demonstrable sex differences in choline incorporation. A slight difference in the incorporation of CDPcholine by separate sexes was evident. Methylation of phosphatidylethanolamine to phosphatidylcholine could not be demonstrated.     

Gait speed is more challenging than cognitive load on the stride-to-stride variability in individuals with anterior cruciate ligament deficiency

Background

Several investigations have studied gait variability of individuals with anterior cruciate ligament (ACL) deficiency; however, the effect of dual-tasking on the gait variability of these individuals remained unclear. The aim of the present study was to determine the effect of gait speed and dual-tasking on knee flexion–extension variability in subjects with and without ACL deficiency.

Polyamines in Trichomonas vaginalis

Trichomonas vaginalis was grown in a modified Bushby's medium and putrescine, spermidine and spermine levels were determined in extracts from 24- and 48-h cultures and also in the culture media. All three polyamines were present in T. vaginalis extracts; the putrescine level and putrescine/spermidine ratio were much higher than those reported for other protozoa or for mammalian tissues. There were no significant differences between 24-h and 48-h amine levels per mg protein in these extracts, but amine levels per cell were higher at 24 than at 48 h. The spent culture media had a much higher putrescine content than corresponding uninoculated media and it was concluded that T. vaginalis secreted putrescine into the culture medium.     

Forebrain and lower brainstem participation in facilitatory and inhibitory regulation of the display of lordosis in female rats

Neural transection of the dorsal extrahypothalamic descending afferents by means of an L-shaped Halász knife at the anterior commissure (anterior roof deafferentation. ARD) markedly potentiated the display of lordosis and soliciting behaviors. Bilateral lesions of the ventromedial hypothalamus (VMH) attenuated lordotic activity in the ARD sham females but not in the ARD females. In contrast, the lesions in the pontine central gray concurrently with ARD effectively inhibited the display of lordosis but not soliciting behaviors. These results suggest that the VMH may not be a primary focus of the dorsal extrahypothalamic inhibitory influence on lordosis. The influence of this inhibitory system seems to be dominant in regulating the expression of lordosis behavior, compared to that of the hypothalamic lordosis facilitating system. Furthermore, the dorsal extrahypothalamic inhibitors influence which could be removed by ARD must be modified by the neural mechanism in the lower brain stem in which the pontine central gray may be actively involved.     

人工培植牛黄中主要成分的薄层色谱扫描法

天然牛黄为名贵中药材,但货源紧缺供不应求,为此拟利用人工培植方法获得天然牛黄以利扩大药源。本文对十七个人工培植牛黄主成分进行定量分析,并与天然牛黄及人工合成牛黄作对比,从成分上探讨了人工培植牛黄的质量。     

主诉腰痛女性患者骨密度和骨质疏松患病率分析

目的研究主诉腰痛女性患者腰椎和髋部骨密度(BMD)测量的临床意义及骨质疏松(OP)患病率。方法采用扇形束双能X线骨密度仪(DEXA)测量主诉为腰痛的女性患者的腰椎和髋部BMD,并与对照组的BMD比较,同时比较其相应骨质疏松(OP)患病率。结果临床主诉以腰痛为主的女性病人腰椎及髋部BMD比以关节痛或全身痛为主诉者的低,(P＜0.05);主诉腰痛者各骨骼部位的OP检出率明显高于关节痛或全身痛者,且均与正常对照组有显著性差异(P＜0.05)。结论骨质疏松是女性腰痛病人就诊的主要原因之一,腰痛患者OP患病率较高;腰椎BMD测定是诊断骨质疏松症的重要手段。     

用腰椎X—线片半定量诊断骨质疏松的研究

目的验证JOA X-线骨质疏松诊断标准的可靠性.方法47名女性病人(年龄65.3±7.2岁)行腰椎常规X-线检查和第三腰椎正、侧位DEXA骨密度测量.用t检验验证X-线骨质疏松等级间骨密度的差异性,用Spearman相关性分析法检验X-线骨质疏松等级与骨密度值的相关性.结果X-线骨质疏松等级间骨密度具有显著性差异(P＜0.01),X-线骨质疏松等级与第三腰椎侧位骨密度值之间相关性最高(r=0.714).结论通过腰椎X-线片按照JOA标准划分骨质疏松等级,可以作为粗略检查腰椎骨质疏松的方法.     

益母草中阿魏酸的色谱鉴别

目的：鉴别益母草中是否含阿魏酸,方法：采用薄层色谱法和高效液相色谱法鉴别不同提取溶煤制备的样品,结果：从益母草中能检出阿魏酸。结论：益母草中可能含游离的阿魏酸,以5％Na2CO3溶液替代药典中的甲醇提取,方法简化,稳定性高,重现性好。