兔眼前房压强在体连续测量方法的研究

为了解眼睛房水压强变化规律,进一步建立闭角型青光眼模型和对疾病的治疗及视功能康复提供参考,探讨一种在体连续测量正常兔眼前房压强的方法。将正常成年新西兰白兔麻醉后,先用静脉留置针(20G)自角膜缘外行前房穿刺术,然后通过套管将Millar导管植入兔眼的前房,兔眼的前房压强信号经过Powerlab系统进行滤波、放大和模数转换后,通过Chart软件进行实时显示。结果表明:用该方法测得的正常兔眼24 h前房压强的变化范围为(1.31±0.21—2.74±0.83)KPa。前房压强的分布凌晨较低(0~5点),然后逐渐升高(5~10点),到中午或下午(11—17点)时达到最高峰,晚上又逐渐下降(18~23点)。结果证明本实验在体连续测量兔眼前房压强的方法是可行的。     

Strain-specific development of the mossy fiber system in organotypic cultures of the mouse hippocampus

The postnatal development of the hippocampus of the inbred mice strains BALB/c, C57BL/6, and DBA/2 was studied in organotypic explant cultures using the roller-tube technique. In vivo, mice exhibit strain-specific mossy fiber distribution patterns. As a main result we found, that after cultivation of 3-4 weeks, similar strain-specific patterns became apparent in vitro, as visualized by a modified Timm staining. From this experiment we can conclude that a postnatal extrinsic influence cannot be the cause of the strain-specific hippocampal features.     

The cauliflower mosaic virus translational transactivator interacts with the 60S ribosomal subunit protein L18 of Arabidopsis thaliana

The cauliflower mosaic virus (CaMV) open reading frame VI product (P6) is involved in several aspects of the infectious cycle. P6 specifically controls the synthesis of other CaMV proteins by transactivating their expression from the polycistronic 35S RNA. By far-Western assays, we have demonstrated that P6 interacts with proteins from both healthy and CaMV-infected leaves of Arabidopsis thaliana. These proteins are found in ribosome-enriched extracts, suggesting that they participate in the translation process. One of these proteins, identified by microsequencing, corresponds to the 60S ribosomal subunit protein L18 (RPL18). Its cDNA was cloned and expressed in Escherichia coli, and the resulting RPL18 protein was shown to interact with the minimal region required for translational transactivation, designated the miniTAV domain of P6.     

膀胱移行细胞癌中PTEN的表达分析

目的研究PTEN在膀胱移行细胞癌（TCC）中的表达。方法应用免疫组织化学染色方法观察52例TCC标本PTEN的表达情况。结果TCC组中PTEN的阳性表达率为71.2%,而10例正常膀胱粘膜组织PTEN表达均为阳性。PTEN表达与膀胱肿瘤病理分级、临床分期密切相关。结论PTEN的异常表达在TCC的发生、发展过程中起重要作用。该指标的检测有助于预后判断。     

Glucose Ingestion Attenuates Interleukin-6 Release from Contracting Skeletal Muscle in Humans

To examine whether glucose ingestion during exercise affects the release of interleukin-6 (IL-6) from the contracting limb, seven men performed 120 min of semi-recumbent cycling on two occasions while ingesting either 250 ml of a 6.4 % carbohydrate (GLU trial) or sweet placebo (CON trial) beverage at the onset of, and at 15 min intervals throughout, exercise. Muscle biopsies obtained before and immediately after exercise were analysed for glycogen and IL-6 mRNA expression. Blood samples were simultaneously obtained from a brachial artery and a femoral vein prior to and during exercise and leg blood flow was measured by thermodilution in the femoral vein. Net leg IL-6 release, and net leg glucose and free fatty acid (FFA) uptake, were calculated from these measurements. The arterial IL-6 concentration was lower (   P < 0.05  ) after 120 min of exercise in GLU, but neither intramuscular glycogen nor IL-6 mRNA were different when comparing GLU with CON. However, net leg IL-6 release was attenuated (   P < 0.05  ) in GLU compared with CON. This corresponded with an enhanced (   P < 0.05  ) glucose uptake and a reduced (   P < 0.05  ) FFA uptake in GLU. These results demonstrate that glucose ingestion during exercise attenuates leg IL-6 release but does not decrease intramuscular expression of IL-6 mRNA.     

Relationship of human adenoviruses 12, 18, and 31 as determined by hemagglutination inhibition.

Adenoviruses 12 and 31, but not Ad18, agglutinate rat blood cells at high titer, providing suitable blood cells be available and a prolonged contact period of virus with the erythrocytes is allowed. Purified virus particles show direct, and virus-free supernatants show direct and indirect, hemagglutination, ie, enhancement of HA by heterologous antiserum. Hemagglutination inhibition with rabbit antisera shows cross-reactions between Ad12 and Ad31 with titers 4--32 times lower than with homologous antigens; Ad18 antisera react with antigens from both of the other serotypes. No cross-reactions were seen with antisera from other adenoviruses. This suggests an antigenic relationship of the three viruses of subgroup IV in their fiber antigen gamma, in addition to the known relation in the hexon (epsilon), which is apparent in cross-neutralization.     

Quantitative bone remodelling resulting from the use of porous dental implants

Histomorphometric analyses were used to quantitatively determine the patterns of bony ingrowth which resulted from the placement of porous-surfaced dental implants into the mandibles of Rhesus monkeys for up to 74 months utilizing a two-stage approach. Quantitative histopathologic evaluations were made using ground section microscopy. Implant stability resulting from bone remodelling and ingrowth occurred to varying degrees with all implants. Bone ingrowth occurred from medullary trabeculae and contact with the adjacent cortical plates. Quantitative histomorphometric analyses revealed that in only one case was the bone ingrowth into the available internal pores less than 45%. Minimal fibrous connective tissue ingrowth was observed in the implant crypts and was not thought to be due to micro-motion. The observed bone remodelling indicated a favorable prognosis for long-term implant performance.     

Aortic endothelial cell proteoheparan sulfate. II. Modulation by extracellular matrix.

The effects of extracellular matrix components on proteoheparan sulfate biosynthesis was studied for bovine aortic endothelial cells in tissue culture. When the cells were maintained on a variety of different purified components of the extracellular matrix, the cells expressed the same three species of proteoheparan sulfates as the cells cultured on tissue culture plastic (HS I, HS II, and HS III). However, the amounts of the three species recovered from the tissue culture medium were found to be dependent on the substrate on which the cells are grown as well as on other factors. In comparison with plastic, much less HS I was found in the medium of cells maintained on substrates containing diverse matrix molecules, whereas the amounts of HS II and HS III essentially remained the same. In contrast, when bovine aortic organ cultures were analyzed under pulsatile flow, marked differences in the profile of proteoheparan sulfate biosynthesis were observed: HS I was found exclusively associated with the plasma membrane of the endothelial cells; HS II was localized only to the subendothelial matrix; and HS III represented the only proteoheparan sulfate species in the medium. This distribution is consistent with polarized secretion and deposition into the subcellular matrix of HS III and retention of HS I in the plasma membrane in the organ culture situation, a biosynthetic phenotype which can only be approximated at best by maintaining the endothelial cells on a substrate other than plastic. When aortic media (devoid of endothelial cells) was placed in organ culture, no HS III could be detected, which suggested that the vascular endothelial cell is the major cell type responsible for its synthesis in organ culture. Thus, the extracellular matrix, depending upon its composition and organization, may play an important role in stabilizing cell polarity and thereby contribute to maintenance of the differentiated phenotype appropriate for the endothelial cell.     

The effect of indomethacin on cerebral blood flow and oxygen consumption in the rat at normal and increased carbon dioxide tensions

The effect of the fatty acid cyclo-oxygenase inhibitor indomethacin on cerebral blood flow (CBF) and the metabolic rate for oxygen (CMRO₂) was studied in paralyzed and artificially ventilated rats. In normocapnic animals, the drug (10 mg·kg^-1i. v.) reduced CBF to 50% of control without a measurable effect on CMRO₂. During hypercapnia (Pa_CO2 70–80 mmHg) the increase in CBF was reduced by about 80% but CMRO₂ remained unchanged. Autoradiographic evaluation of local CBF in 20 brain structures indicated that the reduction in CBF was relatively uniform throughout the brain. Dose response curves showed that an effect on CBF was evident already at an indomethacin dose of 1 mg·kg^-1 and maximal effects were obtained with 3–5 mg·kg^-1. Following i. v. injection of the drug reduction in CBF was observed already after 10 s and the full response occurred after 1–2 min. It is concluded that metabolites of arachidonic acid, possibly mainly prostacyclin, are powerful modulators of normal cerebrovascular tone, and help to mediate the CBF response to increased CO₂ tensions. However, since indomethacin does not modify the circulatory response in other conditions with increased CBF these substances do not qualify as general coupling factors controlling CBF in physiological or pathological states.