Depression and Altitude: Cross-Sectional Community-Based Study Among Elderly High-Altitude Residents in the Himalayan Regions

Suicide rates are higher at high altitudes, and some hypothesize that hypoxia is the cause. There may be a significant correlation between rates of depression and altitude, but little data exist outside the United States. The purpose of the present study is to conduct a survey of depression among the elderly highlanders in Asia. We enrolled 114 persons aged 60 years or older (mean, 69.2 ± 6.7 years; women, 58.8 %) in Domkhar (altitude, 3800 m), Ladakh, India and 173 ethnic Tibetans (mean, 66.5 ± 6.1 years; women, 61.3 %) in Yushu (altitude, 3700 m), Qinghai Province, China. The two-item Patient Health Questionnaire (PHQ-2) and the geriatric depression scale were administered. A psychiatrist interviewed the subjects who had a positive score on the PHQ-2. The results of the interview with the residents conducted by the specialist showed that two cases (1.8 %) from Domkhar and four (2.3 %) from Qinghai had depression. Despite the high altitude, the probability of depression was low in elderly highlander in Ladakh and Qinghai. Our finding seems to indicate that cultural factors such as religious outlook and social/family relationship inhibit the development of depression.     

The structure of jujubosides A and B,the saponins isolated from the seeds of Zizyphus jujuba

Stepwise chemical and enzymatic hydrolyses of jujubosides A and B, the saponins of the seeds of Zizyphus jujuba, afforded prosapogenins I, II and III. The sequence and configuration of the sugar linkages in the saponins and the pro-sapogenins were determined from the PMR data and the application of Klyne's rule of molecular rotations and structures were assigned to jujubosides A and B.     

Development of a multiplex PCR assay for the identification of eight species members of the Thai Hyrcanus Group (Diptera: Culicidae)

The Hyrcanus Group comprises important vectors of malaria because of Plasmodium vivax Grassi and Feletti and filariasis caused by Brugia malayi Brug in many countries of South, Southeast and East Asian regions. In Thailand, eight species members (Anopheles argyropus Swellengrebel, An. crawfordi Reid, An. nigerrimus Giles, An. nitidus Harrison, Scanlon & Reid, An. paraliae Sandosham, An. peditaeniatus Leicester, An. pursati Laveran and An. sinensis Wiedemann) of the Hyrcanus Group have been recognized. Due to morphological overlap, adult females of the Hyrcanus Group in Thailand have been misidentified markedly among the eight species, particularly when using the traumatic scales of wild-caught specimens from epidemiology and control approaches. Therefore, this study first developed a simple and robust multiplex PCR assay, based on second internal transcribed spacer sequences of ribosomal DNA, for differentiating the eight species members of the Thai Hyrcanus Group.     

Three-dimensional co-culture model employing silica nonwoven fabrics to enhance cell-to-cell communication of paracrine signaling between hepatocytes and fibroblasts

The realization that soluble factors secreted by heterotypic cells play an importanta role in paracrine signaling, which facilitates intercellular communication, enabled the development of physiologically relevant co-culture models for drug screening and the engineering of tissues, such as hepatic tissues. The most crucial issues confronting the use of conventional membrane inserts in segregated co-culture models that are used to study paracrine signaling between heterotypic cells have been identified as long-term viability and retention of cell-specific functions, especially when isolated primary cells are used. Herein, we present an in vitro segregated co-culture model consisting of a well plate incubated with rat primary hepatocytes and normal human dermal fibroblasts which were segregated using a membrane insert with silica nonwoven fabric (SNF) on it. SNF, which mimics a physiological environment much more effectively than a two-dimensional (2D) one, promotes cell differentiation and resultant paracrine signaling in a manner that is not possible in a conventional 2D culture, owing to high mechanical strength generated by its inorganic materials and interconnected network structure. In segregated co-cultures, SNF clearly enhanced the functions of hepatocytes and fibroblasts, thereby showing its potential as a measure of paracrine signaling. These results may advance the understanding of the role played by paracrine signaling in cell-to-cell communication and provide novel insights into the applications of drug metabolism, tissue repair, and regeneration.     

Further structural studies of an anti-complementary acidic heteroglycan from the leaves of Artemisia princeps

Partial acid hydrolysis of the anti-complementary acidic heteroglycan, AAFIIb-3, isolated from the leaves of Artemisia princeps PAMP gave the oligosaccharides Gal-(1→6)-Gal, Gal-(1→6)-Gal-(1→6)-Gal, GalA-(1→4)-Rha, GalA-(1→2)-Rha, GlcA-(1→4)-Gal, GlcA-(1→4)-Rha, GlcA-(1→6)-Gal, and GlcA-(1→4)-Xyl. On methylation of AAFIIb-3 without de-esterification, 4-linked and 3,6-disubstituted galactan, 3-linked galactan, 4-linked galactan, and branched arabinan-rich fragments were obtained. The results of base-catalysed β-elimination indicated that AAFIIb-3 has a backbone consisting of 4-linked GalA and 2-linked Rha to which a highly branched arabino-3,6-galactan and arabino-4-galactan are linked at positions 4 of some 2-linked Rha units. Xyl-(1→4)-GalA, GlcA-(1→4)-Xyl-GalA, and →3)-Gal-(1→4)-GalA might also be joined to other 2-linked Rha at the same position. Some 6-linked and 4-linked Gal were terminated by GlcA.     

Detection of cholera toxin by a highly sensitive bead-enzyme linked immunosorbent assay.

A bead-enzyme linked immunosorbent assay (bead-ELISA) for detection and quantification of cholera toxin (CT) in broth cultures of Vibrio cholerae O1 has been developed. Under optimal buffer and pH conditions the bead-ELISA could consistently detect 40 pg/ml of CT. None of the ingredients of commonly used media for in vitro culture of V. cholerae O1 hindered the performance of the bead-ELISA. Evaluation of the sensitivity and specificity of the bead-ELISA against the commonly used reversed passive latex agglutination (RPLA) test for detection of CT was performed using a collection of 239 strains of V. cholerae O1 (including both biotypes and serotypes) which were examined by a gene probe encoding for the A1 subunit of CT. Although both the assays were highly specific, the bead-ELISA was more sensitive than the RPLA. Quantification of CT by the bead-ELISA revealed that the concentration of CT produced by the strains of V. cholerae O1 which were negative by the RPLA was lower than 1 ng/ml and therefore below the minimum detection ability of the RPLA. The bead-ELISA is a simple, specific and highly sensitive assay for routine detection of CT and is recommended for routine use in clinical microbiology laboratories.