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91.
92.
Soil-transmitted helminth (STH) infections are endemic in Indonesia. However, prevalence data for many parts of the country are incomplete. The aim of this study was to determine human STH prevalence and knowledge and practices relating to STH risk behaviour, to provide a current view of the status of STH infection in rural communities in Central Java. A cross-sectional survey of 16 villages was conducted in Semarang, Central Java in 2015. Demographic and household data together with information about knowledge and practices relating to STH and hygiene were elicited through face-to-face interviews. Stool samples were collected and examined using the flotation method. Children (aged 2–12 years) also had their haemoglobin (Hb) levels, height and weight data collected, and BMI estimated. Data were analysed using univariate logistic regression analysis. A total of 6,466 individuals with a mean age of 33.5 years (range: 2–93) from 2,195 households were interviewed. The overall prevalence of STH was 33.8% with Ascaris lumbricoides (roundworm) the predominant nematode identified (prevalence = 26.0%). Hookworm and Trichuris trichiura (whipworm) were found in 7.9% and 1.8% of participants, respectively. Females were at increased odds of infection with A. lumbricoides (adjusted OR 1.14, 95% CI [1.02–1.29], p = 0.02). Adults in age groups 51–60 and over 60 years had the highest odds of being infected with hookworm (adjusted OR 3.01, 95% CI [1.84–4.91], p<0.001 and adjusted OR 3.79, 95% CI [2.30–6.26], p<0.001, respectively) compared to 6–12 year olds. Farmers also had higher odds of being infected with hookworm (adjusted OR 2.36, 95% CI [1.17–4.76], p = 0.02) compared to other occupation categories. Poverty (OR 2.14, 95% CI [1.77–2.58], p<0.001), overcrowding (OR 1.35, 95% CI [1.27–1.44], p<0.001), goat ownership (OR 1.61, 95% CI [1.10–2.41], p = 0.02) and the presence of dry floor space in the home (OR 0.73, 95% CI [0.58–0.91], p = 0.01) were all household factors significantly associated with an increased odds of infection. Infection with STH was not significantly associated with the gastrointestinal illness (p>0.05), BMI or Hb levels; however, one third of all 2–12 year olds surveyed were found to be anaemic (i.e. Hb concentrations below 110g/l or 115g/l for children under 5 and 5 years or older, respectively), with a greater proportion of school-age children at risk. Knowledge and behaviour related to hygiene and gastrointestinal diseases varied widely and were generally not associated with STH infection. The study revealed that STH infection remains endemic in Central Java despite ongoing deworming programs. Current control efforts would benefit from being re-evaluated to determine a more effective way forward.  相似文献   
93.
Human cytomegalovirus (HCMV) exerts anti-apoptotic effect during early stage of infection, which provides HCMV time for propagation. We investigated pathways mediating the resistance to H(2)O(2)-induced cell death - a self-defense mechanism to remove infected cells. We found that human aortic endothelial cells (HAECs) infected with VHL/E strain of HCMV during first 3 days were resistant to H(2)O(2) (0-2 mM) induced apoptosis. This anti-apoptotic effect may be mediated by the upregulation of Bcl-2, an anti-apoptotic protein through the activation pro-survival pathway extracellular signal regulated kinase (ERK). Through this mechanism, HCMV is able to propagate and causes endothelial dysfunction, hence vascular disease.  相似文献   
94.
Supernodulating soybean (Glycine max L. Merr.) mutant SS2-2 and its wild-type counterpart, Sinpaldalkong 2, were examined for the microstructural events associated with nodule formation and development. SS2-2 produced a substantially higher percentage of curled root hairs than the wild type, especially at 14 days after inoculation with Bradyrhizobium japonicum. In addition, there was new evidence that in SS2-2, B. japonicum also entered through fissures created by the emerging adventitious root primordia. Early steps of nodule ontogeny were faster in SS2-2, and continued development of initiated nodules was more frequent and occurred at a higher frequency than in the wild type. These data suggest that the early expression of autoregulation is facilitated by decreasing the speed of cortical cell development, leading to the subsequent termination of less-developed nodules. The nodules of SS2-2 developed into spherical nodules like those formed on the wild type. In both the wild type and supernodulating mutant, vascular bundles bifurcate from root stele and branch off in the nodule cortex to surround the central infected zone. These findings indicate that SS2-2 has complete endosymbiosis and forms completely developed nodule vascular bundles like the wild type, but that the speed of nodule ontogeny differs between the wild type and SS2-2. Thus, SS2-2 has a novel symbiotic phenotype with regard to nodule organogenesis.  相似文献   
95.
ABSTRACT: BACKGROUND: Sabang Municipality, in Aceh Province, Indonesia, plans to initiate a malaria elimination programme in 2013. A baseline survey of the distribution of malaria in the municipality was conducted to lay the foundations for an evidence-based programme and to assess the island's readiness to begin the elimination process. METHODS: The entire population of the municipality was screened for malaria infection and G6PD deficiency. Specimens collected included blood slides, blots and tubes for selected households. Results and Discussion Samples were collected from 16,229 residents. Microscopic examination of the blood smears revealed 12 malaria infections; 10 with Plasmodium falciparum and 2 with Plasmodium vivax. To confirm the parasite prevalence, polymerase chain reaction (PCR) diagnosis was performed on the entire positive cases by microscopy and randomized 10% of the microscopically negative blood samples. PCR revealed an additional 11 subjects with malaria; one P. falciparum infection from the village of Paya Keunekai, and nine P. vivax infections and one mixed P. falciparum/P. vivax infection from the village of Batee Shok. The overall slide positivity rate was 0.074% (CI 95%: 0.070 - 0.078) and PCR corrected prevalence 0,590% (CI 95%: 0.582 - 0.597). Analysis of 937 blood samples for G6PD deficiency revealed two subjects (0.2%) of deficient G6PD. Analysis of several genes of the parasite, such as Pfdhfr, Pfdhps, Pfmdr1, Pfcrt, Pfmsp1, Pfmsp2, Pvdhfr, Pvdhps, Pvmdr1 and host gene, such as G6PD gene revealed that both P. falciparum and P. vivax carried the mutation associated with chloroquine resistance. CONCLUSION: Malariometric and host genetic analysis indicated that there is a low prevalence of both malaria and G6PD deficiency in the population of Sabang Municipality. Nevertheless, malaria cases were clustered in three rural villages and efforts for malaria elimination in Sabang should be particularly focused on those three villages.  相似文献   
96.
The use of triploid fish may be of interest in research, e.g. study of how this condition affects the size and activity of cells. In addition, triploid fish are sterile and production of triploids in fish species that are marketed after reaching sexual maturity may be of economic interest. In the present study, the effects of triploidy on the activity of several components of the innate immune system of turbot (Psetta maxima L) were determined. Triploid turbot had bigger cells (erythrocytes and neutrophils) but the number of blood erythrocytes, leucocytes and thrombocytes was lower than in diploid fish. The differential cell count was similar in both types of fish. The respiratory burst and the phagocytic activities were higher in neutrophils of triploid turbot. However, because the number of neutrophils was higher in diploids, the total respiratory burst activity and the phagocytosis per microliter of blood was similar in both types of fish. No differences were found in serum complement, lysozyme or bactericidal activities. The results indicate that the activities of the humoral components of the innate immune system tested are similar in diploid and triploid fish and that the lower leucocyte number found in triploids is compensated for by higher cell activity.  相似文献   
97.

Background

Enteroaggregative Escherichia coli (EAEC) is one of the most common bacterial pathogens associated with the etiology of persistent diarrhea. A characteristic feature of EAEC-pathogenesis is the induction of profound inflammatory response in the intestinal epithelium. The present study was designed to investigate the underlying mechanism of inflammatory responses induced by a novel galactose specific adhesin of T7 strain of EAEC (EAEC-T7) in human intestinal epithelial cell line (INT-407).

Methods

INT-407 cells were stimulated with the adhesin in the absence and presence of anti-adhesin (IgGAD)/d-galactose/H7/staurosporin (inhibitor of PKC)/PD098059 (inhibitor of MEK)/SB203580 (inhibitor of p38-MAPkinase)/AG490 (inhibitor of JAK (-2,-3)/STAT-3 pathway). The expression of activated Raf-1, MEK-1, ERK1/2, JNK, p38-MAPK and STAT-3 was analyzed by Western immunoblot. Release of interleukin-8 (IL-8) was measured by ELISA.

Results

The adhesin was found to induce activation of Raf-1, MEK-1, ERK1/2, p38-MAPK and STAT-3, which was reduced in the presence of IgGAD/d-galactose. The activation of Raf-1 was found to be attenuated in the presence of H7/staurosporin. The expression of phosphorylated STAT-3 was downregulated in the presence of AG490 and PD098059. Further, the adhesin induced IL-8 secretion was reduced in the presence of the inhibitors of MEK (PD098059), p38-MAPK (SB203580) and JAK (-2,-3)/STAT-3 pathway (AG490).

Conclusions

We propose that STAT-3 activation is quintessential for the galactose specific adhesin induced IL-8 secretion by INT-407 cells and must occur in concert with the activation of ERK1/2.

General significance

Our contribution regarding the galactose specific adhesin mediated signaling leads to an improved understanding of the EAEC-pathogenesis and may provide novel therapeutic approaches to combat EAEC infection.  相似文献   
98.
Vertebrate pigment cells are derived from neural crest cells and are a useful system for studying neural crest-derived traits during post-embryonic development. In zebrafish, neural crest-derived melanophores differentiate during embryogenesis to produce stripes in the early larva. Dramatic changes to the pigment pattern occur subsequently during the larva-to-adult transformation, or metamorphosis. At this time, embryonic melanophores are replaced by newly differentiating metamorphic melanophores that form the adult stripes. Mutants with normal embryonic/early larval pigment patterns but defective adult patterns identify factors required uniquely to establish, maintain or recruit the latent precursors to metamorphic melanophores. We show that one such mutant, picasso, lacks most metamorphic melanophores and results from mutations in the ErbB gene erbb3b, which encodes an EGFR-like receptor tyrosine kinase. To identify critical periods for ErbB activities, we treated fish with pharmacological ErbB inhibitors and also knocked down erbb3b by morpholino injection. These analyses reveal an embryonic critical period for ErbB signaling in promoting later pigment pattern metamorphosis, despite the normal patterning of embryonic/early larval melanophores. We further demonstrate a peak requirement during neural crest migration that correlates with early defects in neural crest pathfinding and peripheral ganglion formation. Finally, we show that erbb3b activities are both autonomous and non-autonomous to the metamorphic melanophore lineage. These data identify a very early, embryonic, requirement for erbb3b in the development of much later metamorphic melanophores, and suggest complex modes by which ErbB signals promote adult pigment pattern development.  相似文献   
99.
2‐Benzoxazolinone (BOA), a type of hydroxamic acid present in cereals and implicated in allelopathy, is now being viewed as a potential candidate for the development of natural herbicides. A study was conducted to determine the effect of BOA on mung bean (Phaseolus aureus) through a multitude of bioassays to understand its physiological and biochemical action. It was observed that BOA significantly decreased the germination of mung bean and its early growth (measured in terms of seedling length and dry weight). A typical dose–response relationship was observed with BOA treatment, and I50 values (concentrations at which 50% inhibition occurs) for germination, seedling length and seedling dry weight were calculated to be 4.3, 0.71 and 0.77 mM , respectively. There was therefore a greater inhibitory effect on seedling growth than on germination. Treated seedlings were characterised by a loss of chlorophyll and decreased respiratory activity, indicating a possible adverse effect of BOA on photosynthetic and respiratory metabolism. Mitotic activity in root‐tip cells of onion (Allium cepa) was completely arrested in response to BOA treatment, and the cells exhibited abnormality in shape and size. BOA also adversely affected rhizogenesis in hypocotyl cuttings of mung bean, indicating an impact on morphogenetic potential. It was associated with significant changes in the protein content and activities of proteases and polyphenol oxidases during the root development phase. This study concludes that BOA interfered with essential biochemical processes in mung bean. Such studies provide useful information on the biochemical and physiological modes of actions of BOA, with a view to its use as a herbicidal compound.  相似文献   
100.
Foliar spraying of Brassica carinata (cv. PC 5) with paclobutrazol (PP 333) at 5, 10 and 20 g ml-1 concentrations, reduced plant height significantly and modified the canopy structure by enhancing the number of branches (primary, secondary and tertiary) and the angle of insertion of primary branches on the main axis. The seed yield per plant also increased mainly due to increase in the number of siliquae per plant. Paclobutrazol increased total dry matter of plants and partitioning coefficients. The leaves in paclobutrazol-treated plants exhibited higher chlorophyll content, and they remained intact on plants for longer than the controls. The seeds from paclobutrazol-treated plants had higher levels of proteins, strarch and total soluble sugars but less total seed oil content.  相似文献   
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