Further evidence in support of the selective uptake and anterograde transport of [I]wheat germ agglutinin by chick retinal ganglion cells

Following intravitreal injection, affinity purified, iodinated wheat germ agglutinin ([¹²⁵I]WGA) is taken up by chick retinal ganglion cells and transported in an anterograde direction to nerve terminals in the optic tectum. The accumulation of axonally transported label in the tectum may be measured quantitatively. Using such an approach, we find that co-injection of [¹²⁵I]WGA with an excess of unlabeled WGA reduces the amount of axonally transported labeled lectin. Since co-injection of comparable levels of soybean agglutinin or Ulex Europeanus-I fails to reduce tectal labeling to a similar extent, and since native WGA at the same concentration does not appear to be toxic to retinal ganglion cells, these results support the hypothesis that the uptake and subsequent anterograde axonal transport of WGA by these cells is a selective process, dependent on a limited number of extra- or intracellular binding sites.     

HIV-associated lipodystrophy

The HIV associated lipodystrophy syndrome is characterized by fat loss from the periphery, fat accumulation in the abdominal, dorsocervical regions and breasts, and hyperlipidaemia, insulin resistance and lactic acidaemia. Although several mechanisms have been proposed to explain these abnormalities, the exact aetiology of the condition remains unclear and will likely prove to be complex. The principal clinical concerns that arise from this disorder are possible increased risks of premature atherosclerosis and cardiovascular disease. A variety of therapeutic interventions, designed to limit these risks, are under evaluation.     

恶性肿瘤中Yap和survivin表达关联研究进展

在恶性肿瘤的发生与发展过程中,肿瘤凋亡抑制因子IAP家族和对其有激活作用的Hippo通路因子起着非常重要作用,以及其重要因子YAP和Survivin在恶性肿瘤的相互作用研究被很多研究者所注目。二者关联的研究可能为临床寻找有效治疗恶性肿瘤的方案提供新的思路。     

The effect of a single low dose of trihexyphenidyl on memory functioning in the healthy elderly.

Medications with anticholinergic properties, when taken at therapeutic doses, are known to adversely affect memory functioning in young adults and the elderly. However, their impact at lower doses in geriatric persons has been less thoroughly studied. We investigated the impact of a single 2-mg dose of trihexyphenidyl on memory functioning in 20 healthy elderly subjects using a within-subjects, double-blind comparison with a placebo. Memory functioning was evaluated using subtests of the Wechsler Memory Scale. Subjects also rated the perceived impact of medication on their performance following memory testing. Results indicated that the single 2-mg dose of trihexyphenidyl produced impaired performance on measures of immediate and half-hour delayed recall of complex verbal and visual material when compared to the placebo condition. However, differences were not found on several other memory measures, including general orientation, attention-concentration, and learning of word associations. The significance of these selective memory deficits and suggestions regarding future research are discussed.     

Strain‐dependent induction of allergic rhinitis without adjuvant in mice

BACKGROUND: To date, no murine models have been reported to show the induction of both antigen-specific IgE and nasal eosinophilia, two of the major hallmarks of allergic rhinitis, after local sensitization in the absence of adjuvants, a phenomenon which reflects natural exposure. In this report, we attempted to establish a murine model representing an initiation of allergic rhinitis. METHODS: BALB/c, CBA/J, and C57BL/6 mice were sensitized intranasally to Schistosoma mansoni egg antigen (SEA) solely. After repeated sensitization, serum Ab titers, nasal eosinophilia, and cytokine production by nasal lymphocytes were determined. RESULTS: BALB/c mice produced SEA-specific IgE after repeated sensitization. High-dose sensitization to SEA induced IgE production in CBA/J mice, while C57BL/6 mice did not show the production throughout the period observed, suggesting that IgE production was regulated genetically. BALB/c mice also exhibited nasal eosinophilia after the nasal challenge. In addition, nasal lymphocytes sensitized with SEA intranasally produced significant amount of IL-5 in vitro. CONCLUSIONS: These results suggest that intranasal sensitization with SEA in the absence of adjuvants induces a Th2 immune reaction, reflecting the hallmarks of the initiation of allergic rhinitis both in vivo and in vitro, which is genetically regulated.     

Carnosine in the brain and olfactory system of amphibia and reptilia: A comparative study using immunocytochemical and biochemical methods

The pattern of distribution of carnosine-like immunoreactivity and its relation to glial fibrillary acidic protein immunoreactivity have been studied in two lizards (Gallotia galloti and Tarentola delalandii) and in two anuran amphibians (Rana esculenta and Xenopus laevis) using immunocytochemical techniques. Biochemical data obtained by paper electrophoresis show that the dipeptides carnosine and homocarnosine are both present in the brain of all the species examined. In the central nervous system of both anurans and reptilians, carnosine immunoreactivity is localized in glial cells. An important species difference is, however, seen in the olfactory system since primary olfactory neurons and their processes extending to the olfactory bulb are carnosine positive in reptiles, whereas they are not immunostained in anurans. Thus, the cellular distribution of carnosine immunoreactivity in reptilians is very similar to that observed in birds and mammals and is distinct from that seen in amphibia.