Gender difference in daily time and space use among Bangladeshi villagers under arsenic hazard: application of the compact spot-check method

The compact spot-check method was applied to elucidate the daily time and space use patterns of 121 adults from a Bangladeshi village in which the authors had previously found more skin manifestations due to arsenic poisoning in males than females. The analysis of 2178 spot-check data, which were obtained over a net period of 2 days, highlighted that farming and cash-earning activities were almost exclusively conducted by males. This is probably due to the Muslim Bangladeshi norm for females to be 'sedentary' in or around their own dwellings. Discussion focuses on the advantages of the compact spot-check method and the possibility that males' larger energy expenditure and longer exposure to sunlight are responsible for their severer skin manifestations.     

A highly effective and stable bispecific diabody for cancer immunotherapy: cure of xenografted tumors by bispecific diabody and T-LAK cells

Purpose In the field of cancer immunotherapy research, the targeting of effector cells with specific antibodies is a very promising approach. Recent advances in genetic engineering have made it possible to prepare immunoglobulin fragments consisting of variable domains using bacterial expression systems.Methods We have produced an anti-epidermal growth-factor receptor (EGFR) × anti-CD3 bispecific diabody (Ex3 diabody) in an Escherichia coli (E. coli) expression system with refolding method. The Ex3 diabody targets lymphokine-activated killer cells with a T-cell phenotype (T-LAK cells) to EGFR positive bile duct carcinoma cells with dramatic enhancement of cytotoxicity in vitro. This specific killing of EGFR-positive cells was completely inhibited by parental mAb IgGs directed to EGFR and the CD3 antigen.Results When T-LAK cells were cultured with EGFR-positive tumor cells in the presence of Ex3 diabody, they produced much higher levels of IFN-, GM-CSF, and TNF- than in its absence, this being a possible mechanism underlying specific antitumor activity. The Ex3 diabody showed good stability when tested at 37°C for 48 h, and also markedly inhibited tumor growth of bile duct carcinoma xenografts in severe combined immunodeficient (SCID) mice. When Ex3 diabody (20 g/mouse) was administrated intravenously, together with T-LAK cells and interleukin-2 (IL-2), complete cure of tumors were observed in three of six mice, and the other three showed marked retardation of tumor growth.Conclusion The Ex3 diabody can be considered a highly promising reagent for study of specific targeting immunotherapy against bile duct and other EGFR-positive carcinomas.     

Acetaldehyde alters Ca2+-release channel gating and muscle contraction in a dose-dependent manner

We studied whether acetaldehyde, which is produced by alcohol consumption, impacts ryanodine receptor (RyR) activity and muscle force. Exposure to 50–200 µM acetaldehyde enhanced channel activity of frog RyR and rabbit RyR1 incorporated into lipid bilayers. An increase in acetaldehyde to 1 mM modified channel activity in a time-dependent manner, with a brief activation and then inhibition. Application of 200 µM acetaldehyde to frog fibers increased twitch tension. The maximum rate of rise of tetanus tension was accelerated to 1.5 and 1.74 times the control rate on exposure of fibers to 50 and 200 µM acetaldehyde, respectively. Fluorescence monitoring with fluo 3 demonstrated that 200–400 µM acetaldehyde induced Ca²⁺ release from the sarcoplasmic reticulum (SR) in frog muscles. Acetaldehyde at 1 mM inhibited twitch tension by 12%, with an increased relaxation time after a small, transient twitch potentiation. These results suggest that moderate concentrations of acetaldehyde can elicit Ca²⁺ release from the SR by increasing the open probability of the RyR channel, resulting in increased tension. However, the effects of acetaldehyde at clinical doses (1–30 µM) are unlikely to mediate alcohol-induced acute muscle dysfunction. ryanodine receptor; single-channel current; fluo 3 fluorescence; calcium ion release; calcium ion uptake     

Effects of five-membered ring amino acid incorporation into peptides for coiled coil formation

A five-membered ring amino acid (Ac₅c), the peptides of which exhibit a preference for helical secondary structures, was introduced into peptides for the purpose of designing coiled coil peptides with high binding affinities. We prepared five types of peptides containing Ac₅c with different numbers or at different positions. The incorporation of Ac₅c into peptides enhanced their α-helicities; however, in contrast to our expectations, it did not result in stable coiled coil formation. The structures of side chains in hydrophobic amino acids, not α-helicities appeared to be important for stable hydrophobic interactions between peptides. Although we were unable to develop coiled coil peptides with high binding affinities, the present results will be useful for designing novel coiled coil peptides.     

Tumor‐Targeting Salmonella typhimurium A1‐R Promotes Tumoricidal CD8+ T Cell Tumor Infiltration and Arrests Growth and Metastasis in a Syngeneic Pancreatic‐Cancer Orthotopic Mouse Model

The present study determined the effect of the tumor‐targeting strain Salmonella typhimurium A1‐R (S. typhimurium A1‐R) on CD8⁺ tumor‐infiltrating lymphocytes (TILs) in a syngeneic pancreatic‐cancer orthotopic mouse model. The effect of tumor‐targeting S. typhimurium A1‐R on CD8⁺ TILs was determined on the Pan02 murine pancreatic‐adenocarcinoma implanted orthotopically in the pancreatic tail of C57BL/6 immunocompromised mice. Three weeks after orthotopic implantation, mice were randomized as follows G1: untreated control group (n = 8); and G2: S. typhimurium A1‐R‐treatment group (n = 8, 1 × 10⁷ colony forming units [CFU]/body, iv, weekly, 3 weeks). On the 22nd day from initial treatment, all mice were sacrificed and tumors were harvested. The tumor‐volume ratio was defined as ratio of tumor volume on the 22nd day relative to the 1st day. The tumor volume ratio was significantly lower in the S. typhimurium A1‐R‐treated group (G2) (3.0 ± 2.8) than the untreated control (G1) (39.9 ± 30.7, P < 0.01). Hematoxylin and easin (H&E) staining on tumor sections was performed to evaluate tumor destruction which was classified according to the Evans grading system and found to be much greater in the S. typhimurium A1‐R‐treated mice (G2). Six mice in G1 had peritoneal dissemination, whereas no mice showed peritoneal dissemination in G2 (P < 0.01). Immunohistochemical staining with anti‐mouse CD8⁺ antibody was performed in order to detect TILs determined by calculating the average number of CD8⁺ cells in three high power fields (200×) in the treated and untreated tumors. The TIL score was significantly higher in G2 (133.5 ± 32.2) than G1 (45.1 ± 19.4, P < 0.001). The present study demonstrates that S. typhimurium A1‐R promotes CD8⁺ T cell infiltration and inhibition of tumor growth and metastasis. J. Cell. Biochem. 119: 634–639, 2018. © 2017 Wiley Periodicals, Inc.     

Life histories and soil water content preferences of sympatric exotic and native terrestrial isopods

Exotic species have negative effects on the ecosystems they enter, but often coexist with native species. Clarifying mechanisms behind the coexistence of native and exotic species is important for evaluating effects of such exotic species on native ecosystems. In Japan, at least seven terrestrial isopod species are considered exotic and some have been found with native species. The mechanisms of their coexistence have never been researched. This study examines the hypothesis that an exotic isopod species, Armadillidium vulgare, and native Mongoloniscus koreanus differ in their life histories and soil water content preferences, and that these differences facilitate their coexistence. Field observation revealed that populations of the two species were stably maintained despite large overlap in their life histories and breeding periods, although A. vulgare showed more variability in some aspects of life history than M. koreanus. Two types of choice experiments were carried out to identify their preferences for soil water content levels. The “alone” experiment, where one individual was used per experimental box, showed that the two species were different in preference for soil water content. However, the “group” experiment, where ten individuals of the two species (five of each species) were used per experimental box, suggested that A. vulgare changed its preference from when it was alone, showing preference similar to that of the M. koreanus individuals in the same box. Thus, we concluded that the two species can coexist at the study site, but that the hypothesized mechanisms for their coexistence were not proven in this study.     

Vicariant speciation due to 1.55 Ma isolation of the Ryukyu islands,Japan, based on geological and GenBank data

The Ryukyu island arc, originally a continental margin arc, separated from the Chinese continent by the rifting of the Okinawa trough, a process which began at 1.55 million years ago (Ma) and continues to the present. In addition, the Ryukyu arc was simultaneously divided into the northern Amami–Okinawa and southern Yaeyama islands by the Kerama rift valley, and consequently formed two isolated island units. The Kuroshio warm current began to flow into the Okinawa trough from the Yonaguni Strait, and flow out through the Tsushima and Tokara straits also at 1.55 Ma, and these seaways effectively acted as barriers between the Ryukyu islands and Taiwan, China and Japan. Through this geological process, vicariant speciation generated Ryukyu endemic animal species. We support this hypothesis by drawing linearized maximum likelihood (ML) phylogenetic trees of the species in four endemic insect groups (peacock butterfly, Chinese windmill butterfly, golden‐ringed dragonfly, window firefly) using GenBank sequence data. We determined the precise branching ages for these phylogenetic trees, and show simultaneous speciation at 1.55 Ma for Amami–Okinawa and Yaeyama units. The Taiwan and Tsushima straits, barriers between Taiwan and China, and Japan and Korea, respectively, did not form sufficient barriers to migration during glacial low stands, and species were intermingled. A marine embayment may have posed as a migration barrier between northern and southern China in the Quaternary or a little earlier. From our study we also estimate the precise molecular evolution rate and justify the molecular clock.     

Assessment of the reproductive parameters,laparoscopic oocyte recovery and the first embryos produced in vitro from endangered Canindé goats (Capra hircus)

The Canindé breed of goats (Capra hircus) is currently endangered. The aims of this study were to characterize the estrus behavior, ovulatory responses and progesterone profiles, and to evaluate the in vitro embryo production (IVP) in this breed. In Experiment 1, ten nulliparous and seven pluriparous females received medroxyprogesterone acetate (MAP)-containing sponges (60 mg) plus 75 μg d-cloprostenol for estrus synchronization and their reproductive parameters were evaluated. In Experiment 2, oocytes obtained by laparascopy from hormonally stimulated females (n = 15) were used for IVP. There was no difference (p > 0.05) between nulliparous and pluriparous goats in terms of estrus response (40.0% vs. 85.7%), time from progestagen sponge removal to the onset of estrus (62.0 ± 15.5 vs. 50.7 ± 19.2 h; mean ± SEM), duration of estrus (25.0 ± 16.1 vs. 30.0 ± 15.1 h), percentage of ovulating animals (60.0% vs. 85.7%), number of ovulations (1.2 ± 0.4 vs. 1.3 ± 0.8), and diameter of the preovulatory follicle (5.8 ± 0.5 vs. 6.1 ± 0.3 mm). Progesterone concentrations were also similar (p > 0.05) in both groups. During laparoscopic recovery, there were average 12.2 aspirated follicles and 9.1 oocytes per goat, resulting in a high recovery rate (74.3%, 182/245). A total of 78 embryos were produced (51.0%). The mean number of cells in the blastocysts at day 7 of in vitro culture was 170.3 ± 12.5. In conclusion, nulliparous and pluriparous Canindé goats exhibited similar reproductive profiles. It was possible to produce embryos in vitro, allowing the instigation of an embryo bank for preservation of this breed.