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61.
Human skeletal evidence for the emergence of chronic infectious disease in northern Vietnam is examined. The sample includes the remains of 192 individuals representing the Mid-Holocene and Bronze to Iron Ages. The objective is to see if the transition from sedentary, foraging, coastally oriented economies to centralized chiefdoms with attendant development and intensification of agriculture, trade, metal technologies, warfare, and population increase was accompanied by an emergence of and/or increase in infectious disease. It was found that skeletal evidence for infectious disease was absent in the Mid-Holocene, while over 10% of the Metal period sample exhibited lesions consistent with either infectious disease or immune system disorders. Factors potentially contributing to the emergence of infectious disease in northern Vietnam in the Metal period include: increased contact with bacterial or fungal pathogens either directly or by way of vertebrate and/or arthropod vectors; higher levels of debilitation and/or decreased levels of immunocompetence in the Metal period; and evolution of pathogens present in Mid-Holocene human hosts into more virulent forms in the Metal period. The first two factors may be related to historically and archaeologically documented major demographic (Han colonizing efforts) and economic (agricultural intensification) changes in the region during the Metal period. 相似文献
62.
Staphylococcus epidermidis polysaccharide intercellular adhesin production significantly increases during tricarboxylic acid cycle stress 总被引:1,自引:0,他引:1
Vuong C Kidder JB Jacobson ER Otto M Proctor RA Somerville GA 《Journal of bacteriology》2005,187(9):2967-2973
Staphylococcal polysaccharide intercellular adhesin (PIA) is important for the development of a mature biofilm. PIA production is increased during growth in a nutrient-replete or iron-limited medium and under conditions of low oxygen availability. Additionally, stress-inducing stimuli such as heat, ethanol, and high concentrations of salt increase the production of PIA. These same environmental conditions are known to repress tricarboxylic acid (TCA) cycle activity, leading us to hypothesize that altering TCA cycle activity would affect PIA production. Culturing Staphylococcus epidermidis with a low concentration of the TCA cycle inhibitor fluorocitrate dramatically increased PIA production without impairing glucose catabolism, the growth rate, or the growth yields. These data lead us to speculate that one mechanism by which staphylococci perceive external environmental change is through alterations in TCA cycle activity leading to changes in the intracellular levels of biosynthetic intermediates, ATP, or the redox status of the cell. These changes in the metabolic status of the bacteria result in the attenuation or augmentation of PIA production. 相似文献
63.
Jutiviboonsuk A Zhang H Tan GT Ma C Van Hung N Manh Cuong N Bunyapraphatsara N Soejarto DD Fong HH 《Phytochemistry》2005,66(23):2745-2751
Bioassay directed-fractionation led to isolation of 12 compounds from the roots of Bursera tonkinensis Guillaum (Burseraceae), including burselignan, bursephenylpropane, and burseneolignan. Of the 12 compounds, only 4'-demethyldesoxypodophyllotoxin exhibited significant cytotoxic activities against KB, Col2 and LNCaP cell lines. 相似文献
64.
Cuong Q Nguyen Hongen Yin Byung Ha Lee Wendy C Carcamo John A Chiorini Ammon B Peck 《Arthritis research & therapy》2010,12(6):R220
Introduction
Sj?gren's syndrome (SS) involves a chronic, progressive inflammation primarily of the salivary and lacrimal glands leading to decreased levels of saliva and tears resulting in dry mouth and dry eye diseases. Seminal findings regarding TH17 cell populations that secrete predominantly interleukin (IL)-17A have been shown to play an important role in an increasing number of autoimmune diseases, including SS. In the present study, we investigated the function of IL-17A on the development and onset of SS. 相似文献65.
Dong Tu Nguyen Binh Minh Nguyen Huy Hoang Tran Tuan Cuong Ngo Thanh Huong Le Hoai Thu Nguyen M. John Albert Mamoru Iwami & Masahiko Ehara 《FEMS microbiology letters》2008,284(2):225-230
The genome of the filamentous phage of Vibrio cholerae fs2 was found to contain rst C and rst B1 (truncated) genes downstream of ORF500. att -fs2-dir and att- fs2-rev sequences homologous to that of att -CTXφ were found between orf 500 and rst C of the fs2 genome. This prompted us to search for the integration site of fs2 in the genomes of V. cholerae O1 and O139. The genome of fs2 was found to integrate downstream of att RS of the CTXφ phage, which integrated into chromosome I of V. cholerae O1 and O139. When infected with fs2, a fimbriate strain of V. cholerae O1 appeared to reduce fimbrial production in an adult rabbit ileal loop assay. 相似文献
66.
Van Thu Nguyen Huyen Thanh Nguyen Quoc Cuong Nguyen Phuong Thi Bich Duong Gary West 《PloS one》2015,10(5)
ObjectivesCurrently, HIV testing and counseling (HTC) services in Vietnam are primarily funded by international sources. However, international funders are now planning to withdraw their support and the Government of Vietnam (GVN) is seeking to identify domestic funding and generate client fees to continue services. A clear understanding of the cost to sustain current HTC services is becoming increasingly important to facilitate planning that can lead to making HTC and other HIV services more affordable and sustainable in Vietnam. The objectives of this analysis were to provide a snapshot of current program costs to achieve key program outcomes including 1) testing and identifying PLHIV unaware of their HIV status and 2) successfully enrolling HIV (+) clients in care.MethodsWe reviewed expenditure data reported by 34 HTC sites in nine Vietnamese provinces over a one-year period from October 2012 to September 2013. Data on program outcomes were extracted from the HTC database of 42,390 client records. Analysis was carried out from the service providers’ perspective.ResultsThe mean expenditure for a single client provided HTC services (testing, receiving results and referral for care/treatment) was US $7.6. The unit expenditure per PLHIV identified through these services varied widely from US $22.8 to $741.5 (median: $131.8). Excluding repeat tests, the range for expenditure to newly diagnose a PLHIV was even wider (from US $30.8 to $1483.0). The mean expenditure for one successfully referred HIV client to care services was US $466.6. Personnel costs contributed most to the total cost.ConclusionsOur analysis found a wide range of expenditures by site for achieving the same outcomes. Re-designing systems to provide services at the lowest feasible cost is essential to making HIV services more affordable and treatment for prevention programs feasible in Vietnam. The analysis also found that understanding the determinants and reasons for variance in service costs by site is an important enhancement to the cascade of HIV services framework now adapted for and extensively used in Vietnam for planning and evaluation. 相似文献
67.
Jian Yan Liping Yang Mengqi Cui Xu Wang Kenji Jianzhi Chee Viet Cuong Nguyen Vipin Kumar Afriyanti Sumboja Ming Wang Pooi See Lee 《Liver Transplantation》2014,4(18)
Polyaniline (PANI), a promising conducting polymer for supercapacitor, exhibits high specific capacitance and good rate capability. However, it suffers from low cycling stability due to the breakage or scission of polymer chains and loss of contact caused by the volume change during the charge–discharge, as well as the irreversible oxidation and reduction. Here, a strategy for using aniline tetramers loaded on graphene oxide (AT‐GO) is developed to prevent chain breaking and increase the tolerance of volume change. The potential window is also controlled to reduce the irreversible reactions. In a three electrode test, AT‐GO exhibits a good cycling stability with specific capacitance remaining more than 93 to 96% after 2000 cycles. In a two electrode test, the specific capacitance remains 97.7% of its initial specific capacitance after 2000 cycles by suppressing the side reactions. AT‐GO also shows a high specific capacitance of more than 769 F g?1 at 1 A g?1 and it remains 581 F g?1 at 60 A g?1, suggesting a good rate capability. These results suggest that AT‐GO is a promising electrode material for practical applications. 相似文献
68.
Takashi Tsunoda Tran Chi Cuong Tran Duc Dong Nguyen Thi Yen Nguyen Hoang Le Tran Vu Phong Noboru Minakawa 《PloS one》2014,9(4)
Dengue occurs throughout the year in Hanoi, Vietnam, despite winter low temperatures <10°C. During July 2010 to March 2012, we surveyed monthly for Aedes larvae and pupae in 120 houses in 8 Hanoi districts. Aedes albopictus preferred discarded containers in summer and pupal density drastically decreased in winter. Aedes aegypti preferred concrete tanks and this preference increased in winter. Even in winter, the lowest water temperature found in concrete tanks was >14°C, exceeding the developmental zero point of Ae. aegypti. Although jars, drums and concrete tanks were the dominant containers previously (1994–97) in Hanoi, currently the percentage of residences with concrete tanks was still high while jars and drums were quite low. Our study showed that concrete tanks with broken lids allowing mosquitoes access were important winter refuge for Ae. aegypti. We also indicate a concern about concrete tanks serving as foci for Ae. aegypti to expand their distribution in cooler regions. 相似文献
69.
Luong Huynh Do Nguyen Nguyen Hoai Nguyen Cuong Thach 《Molecular and cellular biochemistry》2021,476(9):3329-3340
Molecular and Cellular Biochemistry - Ginseng is commonly used as an herbal medicine for improvement of life quality. It is also used as a supplemental medication with anti-cancer drugs to enhance... 相似文献
70.
Ha Nguyen Thi Thu Quan Pham Minh Cuong Pham Van Tuyen Nguyen Van Kiem Phan Van Tra Nguyen Thanh Anh Le Thi Tu Marc Litaudon Son Ninh The 《化学与生物多样性》2021,18(11):e2100396
A new racemic xanthone, garmckeanin A ( 1 ), and eight known analogs 2 – 9 were isolated from the ethyl acetate (AcOEt) extract of the Vietnamese Garcinia mckeaniana leaves. Their structures were determined by MS and NMR spectral analyses and compared with the literature. The AcOEt extract showed good cytotoxicity against cancer cell lines KB, Lu, Hep-G2 and MCF7, with IC50 values of 5.40–8.76 μg/mL, and it also possessed α-glucosidase inhibitory activity, with an IC50 value of 9.17 μg/mL. Garmckeanin A ( 1 ) exhibited inhibition of all cancer cell lines, with an IC50 value of 7.3–0.9 μM. Allanxanthone C ( 5 ) successfully controlled KB growth, with an IC50 value of 0.54 μM, higher than that of the positive control, ellipticine (IC50 1.22 μM). Norathyriol ( 8 ) was a promising α-glucosidase inhibitor, with an IC50 value of 0.07 μM, much higher than that of the positive control, acarbose (IC50 161.0 μM). The interactions of the potential α-glucosidase inhibitors with the C- and N-terminal domains of human intestinal α-glucosidase were also investigated by molecular docking study. The results indicated that bannaxanthone D ( 2 ), garcinone E ( 4 ), bannaxanthone E ( 6 ), and norathyriol ( 8 ) exhibit higher binding affinity to the C-terminal than to the N-terminal domain through essential residues in the active sites. In particular, compound 8 could be assumed to be the most potent mixed inhibitor. 相似文献