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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
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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
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MicroRNA‐125b modulates inflammatory chemokine CCL4 expression in immune cells and its reduction causes CCL4 increase with age
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Chemokines play a pivotal role in regulating the immune response through a tightly controlled expression. Elevated levels of inflammatory chemokines commonly occur with aging but the mechanism underlying this age‐associated change is not fully understood. Here, we report the role of microRNA‐125b (miR‐125b) in regulating inflammatory CC chemokine 4 (CCL4) expression in human immune cells and its altered expression with aging. We first analyzed the mRNA level of CCL4 in eight different types of immune cells including CD4 and CD8 T‐cell subsets (naïve, central and effector memory), B cells and monocytes in blood from both young (≤42 years) and old (≥70 years) adults. We observed that monocytes and naïve CD8 T cells expressed higher levels of CCL4 and exhibited an age‐related increase in CCL4. We then found the level of miR‐125b was inversely correlated with the level of CCL4 in these cells, and the level of miR‐125b was reduced in monocytes and naïve CD8 T cells of the old compared to the young adults. Knock‐down of miR‐125b by shRNA in monocytes and naïve CD8 T cells led to an increase of CCL4 protein, whereas enhanced miR‐125b expression by transfection in naïve CD8 T cells resulted in a reduction of the CCL4 mRNA and protein in response to stimulation. Finally, we demonstrated that miR‐125b action requires the ‘seed’ sequence in 3′UTR of CCL4. Together these findings demonstrated that miR‐125b is a negative regulator of CCL4 and its reduction is partially responsible for the age‐related increase of CCL4. 相似文献