Limb blood flow in treated hyperlipoproteinaemic patients with peripheral vascular disease. A preliminary report

Fourteen patients with hyperlipoproteinaemia and peripheral vascular disease have been investigated to determine the effect on limb blood flow of hypolipidaemic therapy. Satisfactory lowering of serum lipoprotein levels was achieved in the treated group. There was a significant deterioration in peak reactive blood flow measurements in the placebo group compared with the treated group. Treatment of hyperlipoproteinaemia may, therefore, be of value in preventing the progression of peripheral atherosclerosis.     

Fluoride retention in human enamel after a single phosphoric acid and mixed phosphoric acid/SnF2 application in vitro

This paper presents evidence that the Snyder/Pope Visual Memory Technique utilizing the Bender-Gestalt Test is a useful predictor of reading ability for first grade children. Subjects were administered the Bender Visual Memory Technique, the Bender-Gestalt Test, and the Digit Span subtest of the WISC-R at the beginning of first grade. The same children were administered the Reading subtest of the Wide Range Achievement Test at the end of first grade. Category scores of the Visual Memory Technique were correlated with the reading achievement results. One category, Rcc (an error-free recall of an error-free original drawing), correlated significantly with later reading ability (r = .43, p = .01). The Digit Span and reading achievement relationship was not found to be significant. Short-term visual recall is probably highly related to the reading task at Grade 1 and should be assessed when children begin to learn to read. Diagnosticians are encouraged to use the technique with attention to the precision category, Recall correct from correct.     

雄蚕丝与普通蚕丝吸放湿性能对比研究

分析比较雄蚕丝与普通蚕丝吸放湿性能。测定在标准条件下雄蚕丝的吸湿、放湿回潮率,绘制出吸湿放湿曲线,并与普通蚕丝进行比较。根据吸湿放湿曲线,推导出标准状态下两种蚕丝的吸放湿速率回归方程。结果表明：雄蚕丝与普通蚕丝达到吸湿放湿平衡的时间及吸湿放湿曲线基本相似,吸湿过程中两种蚕丝达到平衡回潮率的时间几乎相同,但雄蚕丝吸湿能力低于普通蚕丝,而在放湿过程中雄蚕丝达到平衡的时间要低于普通蚕丝。     

Widespread integration and survival of adult-derived neural progenitor cells in the developing optic retina

Adult rat hippocampus-derived neural progenitor cells (AHPC) show considerable adaptability following grafting to several brain regions. To evaluate the plasticity of AHPCs within the optic retina, retrovirally engineered AHPCs were grafted into the vitreous cavity of the adult and newborn rat eye. Within the adult eye, AHPCs formed a uniform nondisruptive lamina in intimate contact with the inner limiting membrane. Within 4 weeks of grafting to the developing eye, the AHPCs were well integrated into the retina and adopted the morphologies and positions of Müller, amacrine, bipolar, horizontal, photoreceptor, and astroglial cells. Although the cells expressed neuronal or glial markers, none acquired end-stage markers unique to retinal neurons. This suggests that the adult-derived stem cells can adapt to a wide variety of heterologous environments and express some but not all features of retinal cells when exposed to the cues present late in retinal development.     

Arp2/3 complex from Acanthamoeba binds profilin and cross-links actin filaments

The Arp2/3 complex was first purified from Acanthamoeba castellanii by profilin affinity chromatography. The mechanism of interaction with profilin was unknown but was hypothesized to be mediated by either Arp2 or Arp3. Here we show that the Arp2 subunit of the complex can be chemically cross-linked to the actin-binding site of profilin. By analytical ultracentrifugation, rhodamine-labeled profilin binds Arp2/3 complex with a Kd of 7 microM, an affinity intermediate between the low affinity of profilin for barbed ends of actin filaments and its high affinity for actin monomers. These data suggest the barbed end of Arp2 is exposed, but Arp2 and Arp3 are not packed together in the complex exactly like two actin monomers in a filament. Arp2/3 complex also cross-links actin filaments into small bundles and isotropic networks, which are mechanically stiffer than solutions of actin filaments alone. Arp2/3 complex is concentrated at the leading edge of motile Acanthamoeba, and its localization is distinct from that of alpha-actinin, another filament cross-linking protein. Based on localization and actin filament nucleation and cross-linking activities, we propose a role for Arp2/3 in determining the structure of the actin filament network at the leading edge of motile cells.