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151.
Hesham M. Al-Mekhlafi Mohamed T. Al-Maktari Rohana Jani Abdulhamid Ahmed Tengku Shahrul Anuar Norhayati Moktar Mohammed A. K. Mahdy Yvonne A. L. Lim Rohela Mahmud Johari Surin 《PLoS neglected tropical diseases》2013,7(10)
Background
Giardia duodenalis infection and malnutrition are still considered as public health problems in many developing countries especially among children in rural communities. This study was carried out among Aboriginal (Orang Asli) primary schoolchildren in rural peninsular Malaysia to investigate the burden and the effects of Giardia infection on growth (weight and height) of the children.Methods/Findings
Weight and height of 374 children aged 7–12 years were assessed before and after treatment of Giardia infection. The children were screened for Giardia parasite using trichrome staining technique. Demographic and socioeconomic data were collected via face-to-face interviews using a pre-tested questionnaire. Overall, 22.2% (83/374) of the children were found to be infected with Giardia. Nutritional status of children was assessed and the results showed that the mean weight and height were 23.9 kg (95% CI = 23.3, 24.5) and 126.6 cm (95% CI = 125.6, 127.5), respectively. Overall, the prevalence of severe underweight, stunting and wasting were 28.3%, 23.8% and 21.0%, respectively. Multiple linear regression analyses showed sex, Giardia infection and household monthly income as the significant determinants of weight while sex and level of mother''s education were the significant determinants of height. Weight and height were assessed at 3 and 6 months after treatment of Giardia infection. It was found that Giardia infection has a significant association with the weight of children but not with height.Conclusions/Significance
This study reveals high prevalence of Giardia infection and malnutrition among Aboriginal children in rural Malaysia and clearly highlights an urgent need to identify integrated measures to control these health problems in the rural communities. Essentially, proper attention should be given to the control of Giardia infection in Aboriginal communities as this constitutes one of the strategies to improve the nutritional status of Aboriginal children. 相似文献152.
153.
Su-Jin Park Hyun-Sook Bae Young-Sik Cho Soon-Ryun Lim Seung-Ae Kang Joo-Cheol Park 《Journal of molecular histology》2013,44(1):65-73
Bone remodeling, the selective deposition and resorption of bone, is an important cause of tooth eruption. During tooth eruption, reduced enamel epithelia of the enamel organ interact with follicle cells to recruit osteoclasts for bone remodeling. However, little is known about the relationship between cellular activity of reduced enamel epithelium and bone resorption during tooth eruption. The purpose of this study was to investigate the effect of apoptosis in reduced enamel epithelium on osteoclastogenesis and its implications for bone resorption. We have analyzed erupting mandibular molars in mice by TdT-mediated dUTP-biotin nick end labeling assay, tartrate-resistant acid phosphatase (TRAP) staining, and immunohistochemistry. TRAP-positive cells were detected in the osteoclasts near both the buccal and lingual sides of tooth socket at postnatal day 0 (PN0). They significantly increased until PN3 and decreased thereafter as the tooth erupted. Interestingly, apoptosis was barely detected in the reduced enamel epithelium at PN3 but clearly at PN7. A few apoptotic cells were also investigated within the dental follicle surrounding developing tooth at PN7 and PN10. We observed apoptotic osteoblast-lineage cells along the inner margin of alveolar bone facing the buccal cusp and at the base of the bony crypt at PN3 decreasing until PN10. In contrast, expression levels of bone sialoprotein increased at PN10 compared to levels at PN3. These results suggest that apoptosis of reduced enamel epithelium resulted in a reduction of osteoclast activity and of bone resorption mediated by dental follicle during tooth eruption. 相似文献
154.
Sona Rajakumari Jun Wu Jeff Ishibashi Hee-Woong Lim An-Hoa Giang Kyoung-Jae Won Randall R. Reed Patrick Seale 《Cell metabolism》2013,17(4):562-574
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155.
156.
Sung‐Hae Park Jongchul Lim Young Soo Kwon In Young Song Jong Min Choi Seulki Song Taiho Park 《Liver Transplantation》2013,3(2):184-192
Nanoporous network polymer nanocomposites with tunable pore size for size‐dependent selective ion transport are successfully prepared via the surface‐induced cross‐linking polymerization of methyl methacrylate (MMA) and 1,6‐hexanediol diacrylate (HDDA) on the surfaces of nanocrystalline TiO2 particles. The morphologies of the porous network polymer layer and nanopores were investigated by transmission electron microscopy (TEM), field emission scanning electron microscopy (FE‐SEM), and Brunauer–Emmett–Teller (BET) experiments. The porous layer size‐selectively screened the ions that contacted the nanocrystalline TiO2 particles, as demonstrated by ion conductivity measurements, electrochemical impedance spectroscopy (EIS), and transient absorption spectroscopy (TAS). 相似文献
157.
We consider an excitatory population of subthreshold Izhikevich neurons which exhibit noise-induced firings. By varying the coupling strength J, we investigate population synchronization between the noise-induced firings which may be used for efficient cognitive processing such as sensory perception, multisensory binding, selective attention, and memory formation. As J is increased, rich types of population synchronization (e.g., spike, burst, and fast spike synchronization) are found to occur. Transitions between population synchronization and incoherence are well described in terms of an order parameter $\mathcal{O}$ . As a final step, the coupling induces oscillator death (quenching of noise-induced spikings) because each neuron is attracted to a noisy equilibrium state. The oscillator death leads to a transition from firing to non-firing states at the population level, which may be well described in terms of the time-averaged population spike rate $\overline{R}$ . In addition to the statistical-mechanical analysis using $\mathcal{O}$ and $\overline{R}$ , each population and individual state are also characterized by using the techniques of nonlinear dynamics such as the raster plot of neural spikes, the time series of the membrane potential, and the phase portrait. We note that population synchronization of noise-induced firings may lead to emergence of synchronous brain rhythms in a noisy environment, associated with diverse cognitive functions. 相似文献
158.
Magdaline Costa Koula Sourris Sue Mei Lim Qing C. Yu Claire E. Hirst Helena C. Parkington Vanta J. Jokubaitis Anthony E. Dear Hong B. Liu Suzanne J. Micallef Kathy Koutsis Andrew G. Elefanty Edouard G. Stanley 《Stem cell research》2013,10(1):103-117
The limited availability of human vascular endothelial cells (ECs) hampers research into EC function whilst the lack of precisely defined culture conditions for this cell type presents problems for addressing basic questions surrounding EC physiology. We aimed to generate endothelial progenitors from human pluripotent stem cells to facilitate the study of human EC physiology, using a defined serum-free protocol. Human embryonic stem cells (hESC-ECs) differentiated under serum-free conditions generated CD34+KDR+ endothelial progenitor cells after 6 days that could be further expanded in the presence of vascular endothelial growth factor (VEGF). The resultant EC population expressed CD31 and TIE2/TEK, took up acetylated low-density lipoprotein (LDL) and up-regulated expression of ICAM-1, PAI-1 and ET-1 following treatment with TNFα. Immunofluorescence studies indicated that a key mediator of vascular tone, endothelial nitric oxide synthase (eNOS), was localised to a perinuclear compartment of hESC-ECs, in contrast with the pan-cellular distribution of this enzyme within human umbilical vein ECs (HUVECs). Further investigation revealed that that the serum-associated lipids, lysophosphatidic acid (LPA) and platelet activating factor (PAF), were the key molecules that affected eNOS localisation in hESC-ECs cultures. These studies illustrate the feasibility of EC generation from hESCs and the utility of these cells for investigating environmental cues that impact on EC phenotype. We have demonstrated a hitherto unrecognized role for LPA and PAF in the regulation of eNOS subcellular localization. 相似文献
159.
Kwangsoo Kim Jae Ho Jeong Daejin Lim Yeongjin Hong Misun Yun Jung-Joon Min Sahng-June Kwak Hyon E. Choy 《PloS one》2013,8(3)
During the last decade, an increasing number of papers have described the use of various genera of bacteria, including E. coli and S. typhimurium, in the treatment of cancer. This is primarily due to the facts that not only are these bacteria capable of accumulating in the tumor mass, but they can also be engineered to deliver specific therapeutic proteins directly to the tumor site. However, a major obstacle exists in that bacteria because the plasmid carrying the therapeutic gene is not needed for bacterial survival, these plasmids are often lost from the bacteria. Here, we report the development of a balanced-lethal host-vector system based on deletion of the glmS gene in E. coli and S. typhimurium. This system takes advantage of the phenotype of the GlmS− mutant, which undergoes lysis in animal systems that lack the nutrients required for proliferation of the mutant bacteria, D-glucosamine (GlcN) or N-acetyl-D-glucosamine (GlcNAc), components necessary for peptidoglycan synthesis. We demonstrate that plasmids carrying a glmS gene (GlmS+p) complemented the phenotype of the GlmS− mutant, and that GlmS+p was maintained faithfully both in vitro and in an animal system in the absence of selection pressure. This was further verified by bioluminescent signals from GlmS
+pLux carried in bacteria that accumulated in grafted tumor tissue in a mouse model. The signal was up to several hundred-fold stronger than that from the control plasmid, pLux, due to faithful maintenance of the plasmid. We believe this system will allow to package a therapeutic gene onto an expression plasmid for bacterial delivery to the tumor site without subsequent loss of plasmid expression as well as to quantify bioluminescent bacteria using in vivo imaging by providing a direct correlation between photon flux and bacterial number. 相似文献
160.
Dong Wook Han Natalia Tapia Marcos J. Araúzo-Bravo Kyung Tae Lim Kee Pyo Kim Kinarm Ko Hoon Taek Lee Hans R. Sch?ler 《PloS one》2013,8(6)
Epiblast stem cells (EpiSCs) and embryonic stem cells (ESCs) differ in their in vivo differentiation potential. While ESCs form teratomas and efficiently contribute to the development of chimeras, EpiSCs form teratomas but very rarely chimeras. In contrast to their differentiation potential, the reprogramming potential of EpiSCs has not yet been investigated. Here we demonstrate that the epiblast-derived pluripotent stem cells EpiSCs and P19 embryonal carcinoma cells (ECCs) exhibit a lower reprogramming potential than ESCs and F9 ECCs. In addition, we show that the low reprogramming ability is due to the lower levels of Sox2 in epiblast-derived stem cells. Consistent with this observation, overexpression of Sox2 enhances reprogramming efficiency. In summary, these findings suggest that a low reprogramming potential is a general feature of epiblast-derived stem cells and that the Sox2 level is a determinant of the cellular reprogramming potential. 相似文献