Stressful life events preceding the acute onset of schizophrenia: A cross-national study from the World Health Organization

This study reports on the findings from a WHO sponsored cross-national investigation of life events and schizophrenia. Data are presented from a series of 386 acutely ill schizophrenic patients selected from nine field research centers located in developing and developed countries (Aarhus, Denmark; Agra, India; Cali, Colombia; Chandigarh, India; Honolulu, USA; Ibadan, Nigeria; Nagasaki, Japan; Prague, Czechoslovakia; Rochester, USA). On a methodological level, the study demonstrates that life event methodologies originating in the developed countries can be adapted for international studies and may be used to collect reasonably reliable and comparable cross-cultural data on psychosocial factors affecting the course of schizophrenic disorders. Substantive findings replicate the results of prior studies which conclude that socioenvironmental stressors may precipitate schizophrenic attacks and such events tend to cluster in the two to three week period immediately preceding illness onset.The paper was prepared by these authors on behalf of the collaborating investigators listed on page 196.     

Microbial transformation of rifamycin B: A new extracellular oxidase fromCurvularia lunata

Summary A highly active extracellular rifamycin oxidase was isolated fromCurvularia lunata var.aeri. The enzyme has a pH optimum of 6.5 and temperature optimum of 50°C.     

The association of thymidine kinase activity and thymidine transport in Escherichia coli

We have constructed a series of mutants within the putative nucleoside-binding site of the herpes simplex type-1 virus (HSV-1) thymidine kinase (TK)-encoding gene (tk), contained within an expression vector. While most mutations within this sequence produce an inactive protein, we find no absolute requirement for the wild-type Ile166 and Ala167. The uptake of thymidine (dT) into Escherichia coli tdk-, lacking functional endogenous TK activity, is proportional to the amount of TK activity expressed from the heterologous HSV-1 tk gene. In contrast, there is no enhancement in deoxycytidine uptake into E. coli producing (HSV-1) TK. These results imply a specific role for TK in the active transport of dT into E. coli.     

Characterization of the oligosaccharide alditols from ovarian cyst mucin glycoproteins of blood group A using high pressure liquid chromatography (HPLC) and high field 1H NMR spectroscopy

A combination of reverse phase and normal phase high pressure liquid chromatography has been used to separate the reduced oligosaccharides produced by alkaline borohydride degradation of a blood group A ovarian cyst mucin glycoproteins. Fourteen compounds, ranging in size from a monosaccharide to a decasaccharide, have been isolated preparatively using a Zorbax C-18 reverse phase column eluted with water and a MicroPak AX-5 normal phase column eluted with aqueous acetonitrile. The purity of the products and their structures were determined from the fully assigned high field proton NMR spectra. The resonances of exchangeable amide protons, observed by the Redfield selective pulse sequence in H2O, were assigned by decoupling to the resonances of H2 of the 2-acetamido sugars. Nuclear Overhauser effects were used to establish the relationship of the anomeric protons and those of the aglycone. In exception to earlier proposals that nuclear Overhauser effect on irradiation of the anomeric proton should always be observed at the proton attached to the aglycone carbon, we find that for the linkage of GalNAcp(1----3)Gal, nuclear Overhauser effect on irradiation of the alpha-anomeric proton resonance is observed not at H3 but at H4 of galactose. A combination of NMR methods and enzymatic degradation was employed to determine the structures of 13 different oligosaccharides of which seven have not previously been reported. These oligosaccharides, which terminate with beta-Gal, alpha-Fuc, beta-GlcNAc, and alpha-GalNAc, account for 75% of the total glycoprotein carbohydrate, the remainder being isolated as a mixture of glycopeptides and a high molecular weight polysaccharide whose NMR spectrum implies a simple repeating subunit structure closely related to that of the oligosaccharides.     

MSI2通过下调circRNA_001214促进急性髓系白血病细胞HL60生长

Musashi-2（MSI2）是一种RNA结合蛋白质,对维持造血干细胞功能具有重要作用。研究表明,MSI2高表达能促进急性髓系白血病（acute myelocytic leukemia, AML）进展,但其作用机制尚不明确。本研究稳定沉默HL60细胞MSI2后,第1、2、3、4 d对照组的相对细胞生长率分别为1.931 ± 0.027、3.070 ± 0.073、4.017 ± 0.092和4.215 ± 0.246;敲减组分别为1.927 ± 0.035、2.564 ± 0.090、2.825 ± 0.097和3.223 ± 0.182,两组相比具有统计学差异,P<0.001;细胞凋亡明显增加(7.967% ± 0.698% vs 3.400% ± 0.322%., P<0.01);G₀/G₁期细胞比例明显增高（67.430% ± 4.390% vs. 50.360% ± 2.160%, P<0.01）;NUMB蛋白明显上调,LEF1明显下降。环状RNA（circular RNA, circRNA）芯片筛选和荧光定量PCR验证显示,MSI2沉默组circRNA_001214表达水平是对照组3.48倍。这一结果也在NALM6细胞得到证实。进一步用生物信息学分析,显示circRNA_001214最可能与miR-1273a、miR-1273e和miR 5095结合,进而影响参与细胞凋亡相关基因（CYCS、AKT1、BAX、TNFRSF10A、TNFRSF10D）、Wnt信号基因（WNT4、WNT2B、WNT7B、 DKK2、SFRP1、CSNKE1和LEF1）以及参与细胞代谢相关基因（RPE, PGAM4, PGAM1, TAT, CBS、RPE、SUCLG2、PGAM4、PGAM1和 IDNK）。总而言之,MSI2可能通过干扰circRNA_001214生成,减少靶miRNA对凋亡、Wnt信号及细胞代谢相关基因表达的影响,促进细胞生长。     

Studies on Antifungal Properties of Essential Oil of Trachyspermum ammi (L.) Sprague

The essential oil from the fruits of Trachyspermum ammi exhibited toxicity at 800 ppm against Aspergillus flavus and A. niger, the nature of toxicity being cidal. The toxicity of the oil was not affected by autoclaving, temperature treatment and storage upto 365 days. The oil killed the test fungi within 50 seconds; withstood heavy inoculum density and was inhibitory to as many as 21 fungi at its minimum inhibitory concentration. However the seeds of Arachis hypogea whentreated with oil at 5000 ppm and stored for 12 months did not show the appearance of any fungi indicating thereby the grain protectant activity of the oil. The oil was characterized by various physico chemical properties and on chemical investigation Thymol and p-cymene were isolated as antifungal principles of the oil exhibiting toxicity against the test fungi at 1000 ppm.     

Magnetic interaction of manganese with pheophytin anion-radical and chlorophyll cation-radical in reaction centers of the photosystem II

The influence of Mn on saturation curves of ESR spectra of Ph(-) and P(+)(680) at 1-200K in samples with different content of Mn has been studied. An analysis of these data and those on photoinduced changes of fluorescence yield of chlorophyll leads to the conclusion that the Mn-containing centre in Photosystem 2 is a cluster of 4 Mn atoms, two of which can be replaced by Mg(2+) or any other divalent metal. The distances between Mn Na Ph as well as between Mn and P(680) have been estimated.