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311.
Shin‐ya Ohba T.T. Trang Huynh Hitoshi Kawada Loan Luu Le Huu Tran Ngoc San Le Hoang Yukiko Higa Masahiro Takagi 《Journal of vector ecology》2011,36(1):170-174
Residents of Vietnam living in areas with water shortages and/or poor tap water maintain water storage containers, such as jars, in and around their domiciles in order to store water used in daily life. Although these water jars are known to be important breeding sources of the Aedes mosquito, use of chemical larvicides in such containers is legally prohibited in Vietnam. In this study, we identified the dominant mosquito insect predators in water jars in and around residences located in Tan Chanh, Long An, southern Vietnam. Of 3,646 Heteroptera collected from such jars, Corixidae (Micronecta spp.) and Veliidae (Microvelia spp.) were revealed to be the dominant predators. Polymerase chain reaction (PCR) analysis revealed that 40% of Micronecta and 12% of Veliidae had Aedes aegypti‐positive reactions, indicating that these two dominant Heteroptera are important predators of Ae. aegypti. Our results suggest that aquatic Heteroptera may be an important mosquito control agent in addition to the currently used copepods. 相似文献
312.
Doanh PN Dung do T Thach DT Horii Y Shinohara A Nawa Y 《Parasitology international》2011,60(4):534-537
Parasitological and sero-epidemiological surveys for human paragonimiasis were conducted in three provinces of Viet Nam. A total of 590 participants from two known endemic areas of human paragonimiasis (Sinho district of Laichau province and Lucyen district of Yenbai province) and from Dakrong district of Quangtri province where we recently found crab hosts heavily infected with Paragonimus westermani metacercariae. By multiple dot-ELISA screening, 28 (12.7%) out of 220 participants in Sinho district of Laichau province and 4 (3.3%) out of 120 participants in Lucyen district of Yenbai province were proven to be antibody-positive against the Paragonimus antigen. None of the 250 sera of the residents in Dakrong, Quangtri province, gave sero-positivity. Among a total of 32 sero-positive patients Paragonimus eggs were found in 6 cases. ITS2 sequences were successfully determined from a single Paragonimus egg from each patient. The results of homology search by BLAST and alignment clearly confirmed that Paragonimus eggs collected from 6 patients were all of Paragonimus heterotremus. The pathogenicity of P. westermani for human paragonimiasis in Viet Nam is still questionable and needs to be explored in the future. 相似文献
313.
314.
Ngo TH Tran TB Tran TT Nguyen VD Campbell J Pham HA Huynh HT Nguyen VV Bryant JE Tran TH Farrar J Schultsz C 《PloS one》2011,6(3):e17943
Streptococcus suis is a pathogen of major economic significance to the swine industry and is increasingly recognized as an emerging zoonotic agent in Asia. In Vietnam, S. suis is the leading cause of bacterial meningitis in adult humans. Zoonotic transmission is most frequently associated with serotype 2 strains and occupational exposure to pigs or consumption of infected pork. To gain insight into the role of pigs for human consumption as a reservoir for zoonotic infection in southern Vietnam, we determined the prevalence and diversity of S. suis carriage in healthy slaughterhouse pigs. Nasopharyngeal tonsils were sampled from pigs at slaughterhouses serving six provinces in southern Vietnam and Ho Chi Minh City area from September 2006 to November 2007. Samples were screened by bacterial culture. Isolates of S. suis were serotyped and characterized by multi locus sequence typing (MLST) and pulse field gel electrophoresis (PFGE). Antibiotic susceptibility profiles and associated genetic resistance determinants, and the presence of putative virulence factors were determined. 41% (222/542) of pigs carried S. suis of one or multiple serotypes. 8% (45/542) carried S. suis serotype 2 which was the most common serotype found (45/317 strains, 14%). 80% of serotype 2 strains belonged to the MLST clonal complex 1,which was previously associated with meningitis cases in Vietnam and outbreaks of severe disease in China in 1998 and 2005. These strains clustered with representative strains isolated from patients with meningitis in PFGE analysis, and showed similar antimicrobial resistance and virulence factor profiles. Slaughterhouse pigs are a major reservoir of S. suis serotype 2 capable of causing human infection in southern Vietnam. Strict hygiene at processing facilities, and health education programs addressing food safety and proper handling of pork should be encouraged. 相似文献
315.
Verwaest KA Vu TN Laukens K Clemens LE Nguyen HP Van Gasse B Martins JC Van Der Linden A Dommisse R 《Biochimica et biophysica acta》2011,1812(11):1371-1379
Huntington disease (HD) is a hereditary brain disease. Although the causative gene has been found, the exact mechanisms of the pathogenesis are still unknown. Recent investigations point to metabolic and energetic dysfunctions in HD neurons. Both univariate and multivariate analyses were used to compare proton nuclear magnetic resonance spectra of serum and cerebrospinal fluid (CSF) taken from presymptomatic HD transgenic rats and their wild-type littermates. N-acetylaspartate (NAA), was found to be significantly decreased in the serum of HD rats compared to wild-type littermates. Moreover, in the serum their levels of glutamine, succinic acid, glucose and lactate are significantly increased as well. An increased concentration of lactate and glucose is also found in CSF. There is a 1:1 stoichiometry coupling glucose utilization and glutamate cycling. The observed increase in the glutamine concentration, which indicates a shutdown in the neuronal-glial glutamate-glutamine cycling, results therefore in an increased glucose concentration. The elevated succinic acid concentration might be due to an inhibition of succinate dehydrogenase, an enzyme linked to the mitochondrial respiratory chain and TCA cycle. Moreover, reduced levels of NAA may reflect an impairment of mitochondrial energy production. In addition, the observed difference in lactate supports a deficiency of oxidative energy metabolism in rats transgenic for HD as well. The observed metabolic alterations seem to be more profound in serum than in CSF in presymptomatic rats. All findings suggest that even in presymptomatic rats, a defect in energy metabolism is already apparent. These results support the hypothesis of mitochondrial energy dysfunction in HD. 相似文献
316.
Peter Geissler Truong Quang Nguyen Trung My Phung Robert Wayne Van Devender Timo Hartmann Balázs Farkas Thomas Ziegler Wolfgang B?hme 《Biologia》2011,66(6):1159-1176
We review the supple skinks (Lygosoma Hardwicke & Gray, 1827) known to occur in Indochina (Cambodia, Laos and Vietnam). Here, the existence of seven species is
documented: L. angeli, L. boehmei, L. bowringii, L. corpulentum, L. haroldyoungi, L. isodactylum (type of Squamicilia Mittleman, 1952), and L. quadrupes (type of Lygosoma). Based on morphological characters, L. carinatum Darevsky & Orlova, 1996 is shown to be a synonym of L. corpulentum. Although L. bowringii is expected to turn out as a complex of cryptic species when molecular methods are applied to a broad sampling, Indochinese
representatives form a homogenous group based on morphology. Two further Lygosoma listed by Bourret (2009), viz. L. albopunctatum and L. punctatum (generotype of Riopa Gray, 1839) are distributed further west and probably fail to reach the Indochinese realm. We also provide natural history
notes and an identification key for the seven species currently recognized from Cambodia, Laos and Vietnam. 相似文献
317.
318.
S. D. Chernyavskikh M. Z. Fedorova Vo Van Thanh Do Huu Quyet 《Cell and Tissue Biology》2012,6(4):348-352
Using the method of confocal laser scanning microscopy, changes in the spatial organization of actin filaments of nuclear
erythrocytes and leukocytes in fish, frogs, and birds during migration were studied. It has been shown that, during movement,
in erythrocytes, like in leukocytes, reorganization of cytoskeleton microfilaments occurs. In the course of migration, in
amphibians and birds, red blood cells form pseudopodia filled with bundles of actin filaments arranged in parallel, whereas
no pseudopodia are formed in fish erythrocytes. The change in the structure of the actin cytoskeleton of nuclear erythrocytes,
like in leukocytes, is responsible for the capability of red blood cells to undergo reactions of migration and phagocytosis. 相似文献
319.
320.
Shen BQ Xu K Liu L Raab H Bhakta S Kenrick M Parsons-Reponte KL Tien J Yu SF Mai E Li D Tibbitts J Baudys J Saad OM Scales SJ McDonald PJ Hass PE Eigenbrot C Nguyen T Solis WA Fuji RN Flagella KM Patel D Spencer SD Khawli LA Ebens A Wong WL Vandlen R Kaur S Sliwkowski MX Scheller RH Polakis P Junutula JR 《Nature biotechnology》2012,30(2):184-189
The reactive thiol in cysteine is used for coupling maleimide linkers in the generation of antibody conjugates. To assess the impact of the conjugation site, we engineered cysteines into a therapeutic HER2/neu antibody at three sites differing in solvent accessibility and local charge. The highly solvent-accessible site rapidly lost conjugated thiol-reactive linkers in plasma owing to maleimide exchange with reactive thiols in albumin, free cysteine or glutathione. In contrast, a partially accessible site with a positively charged environment promoted hydrolysis of the succinimide ring in the linker, thereby preventing this exchange reaction. The site with partial solvent-accessibility and neutral charge displayed both properties. In a mouse mammary tumor model, the stability and therapeutic activity of the antibody conjugate were affected positively by succinimide ring hydrolysis and negatively by maleimide exchange with thiol-reactive constituents in plasma. Thus, the chemical and structural dynamics of the conjugation site can influence antibody conjugate performance by modulating the stability of the antibody-linker interface. 相似文献