酸敏感离子通道与脑梗死

急性脑梗死约占全部脑卒中的70%,病死率和致残率高,且极易复发。但目前针对急性脑梗死在时间窗内溶栓、抗凝等治疗手段不能从根本上切实有效地修复受损脑组织,且伴有出血等风险。寻找脑梗死形成发展的原因并予以治疗迫在眉睫。酸中毒是引起缺血性脑损伤的重要机制。大量实验研究表明,酸中毒能加重神经元的缺血性损伤,且其梗死面积与酸中毒的程度直接相关。但缺血产生的酸中毒如何引起神经元损伤的确切机制尚不明确。最近研究发现酸中毒能激活一种在中枢及周围神经中广泛存在的膜通道,即酸敏感离子通道,它对Ca2+通透,能引起细胞内Ca2+超载,同时能激活胞内酶引起细胞内蛋白质、脂类及核酸的降解,加重缺血后脑损伤。本文就酸敏感离子通道1a与脑梗死做一综述。     

Structure and function of the head in flabelligerid polychaetes

The functional anatomy of the head of Flabelliderma commensalis is described and compared to other flabelligerid polychaetes. Prostomial parts include the dorsal lip, the palps, two pairs of nuchal organs, four eyes and the prostomial lobe and ridge. The eyes are inverse pigment cup types with the medial portions of the sensory cells expanded to form a clear lens-like body. Peristomial parts include the median and ventral lips, the branchial membrane and the branchiae. The derivation of the nephridiopore is unknown. The spiraled branchiae of Coppingeria and the gill books of Diplocirrus are newly described variations in branchial structure. The head is retractable in some species and the anterior setigers are modified to form a protective setal cage. Two methods are employed for feeding: one for host fecal pellets and the other for detrital materials. Chemoreception, respiration, feeding and cleaning rely on a complex pattern of ciliary currents.     

黑龙江省三江平原丹顶鹤的数量分布

在地面调查的基础上,我们使用Y-11轻型飞机对黑龙江省三江平原地区的丹顶鹤的数量分布近行了调查,调查时飞行高度80米,航速140公里/小时,续航里程共3748公里。调查结果表明,丹顶鹤在三江平原主要分布在8个地区,其中嘟噜河下游、洪河自然保护区、七星河流域和兴凯湖低地是主要繁殖地,总数量共309只。     

Modulatory role of substance P on gonadotropin and prolactin secretion in the rabbit.

Substance P (SP) is present in large quantities in the brainstem and hypophysiotropic areas of the brain, but its roles in gonadotropin and prolactin secretion are controversial. The aim of this study was to measure luteinizing hormone (LH), follicle-stimulating hormone (FSH), and prolactin (PRL) release from the pituitary after either intracerebroventricular (ICV) injection or infusion of SP or its C- and N-terminal fragments in intact (INT) and ovariectomized (OVX) conscious rabbits. A single injection of SP into the 3rd cerebral ventricle (3CVT) in INT and OVX rabbits augmented plasma LH concentrations, especially when SP was applied during the initial phase of an LH peak. Injection of SP during the declining phase of LH release was not effective. Injection of SP into the 3CVT was followed by increased plasma PRL concentrations in OVX but not in INT rabbits. Both SP 1-11 and SP 1-7 failed to alter LH, FSH, and PRL secretion when the peptides were slowly infused into the 3CVT, although ICV infusion of SP 6-11 did cause a delayed increase in LH release. The results support a stimulatory role of SP on LH and prolactin release. The results further indicate that although the stimulatory effect of SP on LH is ovarian steroid-independent, in the absence of ovarian steroids, SP is stimulatory only during the rising phase of an LH pulse. A dual role of SP-ergic transmission in modulating LH secretion is discussed.     

New genes in the MHC that encode proteins for antigen processing

Most cells process proteins into short peptides that are displayed on the cell surface bound to class I or class II proteins encoded by the major histocompatibility complex (MHC). These protein-peptide complexes can then be recognized by the circulating lymphocytes of the immune system. Several genes found recently in the MHC encode proteins with possible roles in the supply of peptides to class I molecules. The results imply that the peptides are produced in the cytoplasm by proteasomes and are translocated into the endoplasmic reticulum by 'peptide transporters' related to the multidrug resistance proteins. While there is little biochemical evidence to validate these ideas, Robert DeMars and Thomas Spies discuss here the arguments supporting this view. New data indicate that there may also be factors for class II peptide-processing hidden in the MHC.     

四川省西部鱼类寄生粘孢子虫——1.粘体虫属六新种(粘孢子纲:双壳目)

本文报导四川省西部鱼类寄生粘孢子虫粘体虫属六新种,即异型粘体虫,新种Myxosoma disparis sp.nov.,四川粘体虫,新种Myxosoma sichuanensis sp.nov.,光唇粘体虫,新种Myxosoma acrossochilusi sp.nov.鳅粘体虫,新种Myxosoma nemachilusi sp.nov.斜囊粘体虫,新种Myxosoma obliqua sp.nov.,雅安粘体虫,新种Myxosoma yaanensis sp.nov.。     

Temporal events of gypsy moth vitellogenesis and ovarian development

Abstract The vitellogenic period of gypsy moth ovarian development starts on day 3 of the pupal stage and continues through adulthood. During this period, rapid increases occur in follicle size, protein content, and wet weight of the ovary. Patency is observed on day 3 of the pupal stage.
Pre-vitellogenic follicles are formed in the last larval stadium. Newly formed follicles detach from the germarium on day 4, and increase rapidly to 140 per ovariole at the end of the last larval stadium. The pre-vitellogenic follicles are uniformly around 50 um in diameter. No vitellogenin is incorporated into the oocytes until the pupal stage.
Polyacrylamide gel electrophosesis (PAGE) in the presence of sodium dodecylsulphate (SDS) analysis of male and female haemolymph samples and vitellogenic ovaries demonstrates the presence of two female-specific subunits of vitellogenin of 180 kD and 160 kD. These proteins are detected only in haemolymph and ovarian extracts of vitellogenic females. The molecular weight of the native protein determined by size exclusion chromatography is approximately 400–420 kD.
A highly sensitive double antibody sandwich enzyme-linked immunosorbent assay (ELISA) was developed to monitor the temporal changes in vitellogenin titre in haemolymph. Vitellogenin production starts on day 2 of the last larval stadium, reaching a maximum level by day 6 of the last larval stadium, and decreasing in the late pupal stage as vitellogenin was internalized into the oocytes. This is the first report of vitellogenin production occurring in the larval stage of a holometabolous insect. The fact that vitellogenin production and uptake occur during different stages of development in the gypsy moth, opens up some interesting questions concerning the underlying regulatory mechanisms controlling each process.     

SB subregion of the human major histocompatibility complex: gene organization, allelic polymorphism and expression in transformed cells

The SB region of the human major histocompatibility complex (MHC) has been cloned from cosmid and lambda phage libraries made from the human B-lymphoblastoid cell line Priess (DR4/4, DC4/4, SB3/4). Two alpha genes and two beta genes are encoded in the 100 kb long SB region in the order SB alpha-SB beta-SX alpha-SX beta. The SB alpha and SB beta genes encode the alpha and beta subunits of the SB subset of class II MHC molecules. Both the SX alpha and the SX beta genes are pseudogenes in the haplotype examined. From the isolated clones, the two haplotypes of the Priess cell line, SB3 and SB4, are distinguished by nucleotide sequencing and blot hybridization analyses. Restriction site polymorphisms between the SB3 and SB4 clones were observed only in relatively small regions of the SB beta and SX beta genes. A mouse macrophage cell line was transfected with one of the cosmid clones containing both SB alpha and SB beta genes. Expression of the alpha and beta genes was detected by fluorescene-activated cell sorting (FACS) and two-dimensional gel electrophoresis using SB-specific monoclonal antibodies.