Axonal transport and tissue contents of substance P in rats with long-term streptozotocin-diabetes. Effects of the aldose reductase inhibitor ‘statil’

This study examined the axonal transport of substance P-like immunoreactivity (SPLI) and its content in dorsal root ganglion, trigeminal ganglion, stomach and ileum of non-diabetic rats and two groups of rats with streptozotocin-induced diabetes of 9 months duration. One diabetic group received the aldose reductase inhibitor ‘Statil’ throughout the period of study. To reduce morbidity all diabetic animals were given twice-weekly injections of a long-acting insulin which restricted weight loss but did not prevent regular and severe hyperglycaemia. Axonal transport of SPLI was studied by measurement of accumulation at 12 h ligatures on the left sciatic nerve. There were no differences between the 3 groups either in the calculated anterograde and retrograde mean rates of accumulation (ranges 6.0 to 7.6 and 0.38 to 0.72 mm/h respectively) or mobile fractions of SPLI (means from 0.54 to 0.58). There were, however, marked reductions in anterograde and retrograde accumulations of SPLI in the constricted nerves of the ‘untreated’ diabetics (respectively 57 and 33% of controls;P < 0.01 for both). In the ‘Statil’-treated rats these deficits were attenuated (80 and 75% of controls). Diabetes also reduced the SPLI content of unligated sciatic nerve and trigeminal ganglion (65 and 75% of controls). ‘Statil’ prevented the deficit in the ganglion, but not in the nerve. ‘Statil’ treatment prevented themyo-inositol depletion and attenuated the sorbitol and fructose accumulation seen in the sciatic nerves of the untreated diabetic animals suggesting effective inhibition of aldose reductase in this tissue. The total SPLI content of the stomach and 1-cm segments of ileum were unaltered in the diabetic animals but due to the increased weights of these tissues the SPLI content per unit weight was reduced. These changes were unaffected by ‘Statil’.     

解耦联蛋白在心肌中的表达与心力衰竭

位于心肌线粒体内膜上的解耦联蛋白 (UCPs) ,作为质子通道驱散氧化呼吸时形成的H 梯度 ,使产能转化为产热 ,从而增加呼吸 ,阻止ATP形成 ,并抑制活性氧族的产生 ,最终阻止了心肌细胞的程序性死亡。脂肪酸、寒冷、甲状腺激素、肾上腺素等能调控UCPs的浓度和活性。UCPs在心力衰竭中的作用仍然不清楚 ,有待进一步研究     

嗅神经鞘细胞移植联合应用GDNF促进大鼠脊髓损伤后功能恢复

目的 嗅神经鞘细胞（OECs）移植联合应用胶质源性神经营养因子（GDNF）恢复大鼠脊髓损伤的功能。方法 将成年大鼠分为脊髓半切洞损伤组（A组），脊髓半切洞损伤＋嗅神经鞘细胞移植组（B）和脊髓半切洞＋嗅神经鞘细胞移植＋胶质源性神经营养因子（C组）。手术后应用联合行为评分（CBS），感觉诱发电位（SEP）和运动诱发电位（MEP）检查，测定脊髓功能恢复情况。结果 3组CBS得分A组＞B组＞C组，SEP和MEP潜峰时，均A组＞B组＞C组，统计分析均差异显著性（P＜0．05）。结论 移植嗅神经鞘细胞＋胶质源性神经营养因子能促进损伤脊髓功能的恢复。     

The Effect of Ligustrazine on Peritoneal Transport in Peritoneal dialysis

In order to investigate the effect of ligustrazine (Lig)i.p.on peritoneal permeability in peritoneal dialysis and its side effects,creatinine was given intravenously and continuously to maintain the high plasma creatinine level.All the rabbits were divided into three groups:normal control group (goup A),group B treated with 0.12% Lig and group C treated with 0.24% Lig.The peritoneal dialysis of all rabbits lasted 2h.The plasma and dialysate levels of glucose,protein and creatining were observed immediate,30min,60min,90min,120min after dialysis.Creastinine dialysate/plasma ratio (D/P),protein D/P ratio,grucose D/Do at different time points after dialysis and creatinine mass transfer area coefficient (MTAC) at 120min were calculated.The structures of peritoneum were observed under optical microscope and electron microscope after continuously intraperitoneal injection of Lig for 14 days.The results showed that the 90-min and 12-min creatinine D/P ratios in the group C were higher than in the group A.The 120-min creatinine MATC in the group C was higher than in the group A.The rabbits treated with Lig did not show significant structure changes of peritoneum and signs of peritoneal irritation.It was suggested that Lig could increase mass transfer ability of peritoneum without significant side effects.     

Maturation and aging of the axonal cytoskeleton: biochemical analysis of transported tubulin.

Changes in solubility and axonal transport of tubulin during maturation and aging have been investigated using sciatic motor fibers of rats at 4, 7, 14, 30, and 80 weeks of age. One to six weeks after injection of L-[35S]methionine into the spinal cord, labeled cytoskeletal proteins in consecutive segments of the sciatic nerve and the ventral roots were fractionated into soluble and insoluble forms by extraction in 1% Triton at low temperature. In 4-week-old rats, the two forms of tubulin were transported coordinately in a single wave with the average rate of 2 mm/day. At 7 weeks of age, two components in tubulin transport were observed to develop, possibly reflecting the maturation of the axonal cytoskeleton. The slower main component (1.5 mm/day) contained most of the insoluble form together with the neurofilament proteins and the faster component (3 mm/day) was enriched in the soluble form. Though significantly different in composition, the two components correspond to slow component a (SCa) and slow component b (SCb) originally defined in the optic system. A progressive decrease in transport rates of both SCa and SCb was observed with rats at 14, 30, and 80 weeks of age. In addition, there was a large decrease in the proportion of insoluble tubulin during the course of transport in animals older than 30 weeks. This loss of the insoluble form seems to be accounted for partly by the proteolytic degradation of the severely retarded SCa proteins. Changes in axonal transport of tubulin may thus reflect age-related changes in dynamics and turnover of the axonal cytoskeleton.     

神经活素对Pc12细胞作用的初步观察

从胎脑、颌下腺、肌肉组织中制备神经活素。其性能同脑活素一样：可促进Ｐｃ１２细胞的突起生长，提高其胞浆内乳酸脱氢酶活性，电泳显示二者有相同的三条带。提示：神经活素有可能替代脑活素应用于临床。     

胃肠道间质瘤的临床病理研究

目的：探讨胃肠道间质瘤(gastrointestinal stromal tumor，GIST)的临床病理特点。方法：对55例GIST的病例进行分析，并对其进行CD117、CD34、S-100、SMA、vimenfin、desmin、NF共7种免疫组化分析。结果：肿瘤的发生部位：胃38例(69％)，小肠10例(18％)，其他部位7例(13％)。肿瘤直径0．4—40cm(平均6．7cm)。肿瘤最大直径≥5cm、核分裂像数≥5/50 HPF及有溃疡形成3项在良性与恶性之间差异有显著意义。免疫组化的阳性表达结果为：CD117 39例(71％)、CD34 45例(82％)、S-100 19例(35％)、SMA 12例(22％)、vimentin 32例(58％)、desmin 6例(11％)、NF2／4(50％)。13例良性GIST患者全部存活，42例恶性及潜在恶性GIST中有4例发生转移，13例死亡。结论：(1)GIST好发于中老年人，无明显性别差异。(2)其主要恶性指标为：肿瘤最大径≥5cm、核分裂像≥5／50 HPF和有溃疡形成。(3)光镜下很难将平滑肌性肿瘤及神经源性肿瘤与GIST相鉴别。     

Monoclonal antibodies to canine intra-acrosomal sperm proteins recognizing acrosomal status during capacitation and acrosome reaction

Summary.  Monoclonal antibodies Ds-1 and Ds-2 specifically labelling dog sperm acrosome were prepared by immunization of mice with acetic acid extracts of dog spermatozoa. Electron microscopy and indirect immunofluorescence localized the site of Ds-1 and Ds-2 proteins inside the acrosomal vesicle. Ds-1 antibody detected 55, 76, 115, 120 and 190kDa proteins under non-reducing conditions, and 73 kDa and 54 kDa proteins after reduction (p73/Ds-1 and p54/Ds-1). 92 kDa and 40 kDa proteins recognized by Ds-2 (p92/Ds-2 and p40/Ds-2) migrated at > 200 kDa in the absence of reducing agent. In vivo , p73/Ds-1 and p54/Ds-1 are therefore likely to be present both in free and complexed form, while all of p92/Ds-2 and p40/Ds-2 form disulfide-bonded complexes. Decrease in the rate of acrosomes stained with Ds-1 and Ds-2 was correlated with the progress of capacitation resulting in the increased rate of spontaneous acrosome reactions, as suggested by a dramatic effect of A23187. Monoclonal antibody to boar acrosin (ACR-2) recognized dog sperm acrosin homologue. A higher rate of ACR-2-negative spermatozoa was observed after capacitation and A23187 treatment compared to Ds-1 and Ds-2, indicating that proteins recognized by Ds-1 and Ds-2 are localized in a specific compartment of acrosome, distinct from acrosin and possibly representing fraction of acrosomal matrix.     

Diving physiology and pathophysiology

Summary. Divers have worked at 500 m depth in the sea and have reached 700 m in simulated chamber dives. A prerequisite for this has been extensive physiological studies of the body's reactions to pressure and pressure changes. This paper reviews such physiological and pathophysiological studies with emphasis on recent developments.