Prevalence and determinants of stunting among preschool and school-going children in the flood-affected areas of Pakistan / Prevalência e determinantes da baixa estatura entre crianças em idade pré escolar e em idade escolar nas áreas afetadas pelas enchentes do Paquistão

Stunting is a significant public health problem in low- and middle-income countries. This study assessed the prevalence of stunting and associated risk factors of stunting among preschool and school-going children in flood-affected areas of Pakistan. A cross-sectional study was conducted by visiting 656 households through multi-stage sampling. Respondent's anthropometric measurements, socio-demographic information and sanitation facilities were explored. A logistic regression model was used to determine determinants of stunting, controlling for all possible confounders. The overall prevalence of stunting in children was 40.5%, among children 36.1% boys and 46.3% of girls were stunted. The prevalence of stunting in under-five children was 50.7%. Female children (OR=1.35, 95% CI:0.94-2.0), children aged 13-24 months (OR=6.5, 95% CI: 3.0-13.9), mothers aged 15-24 years (OR=4.4, 95% CI: 2.6-7.2), joint family (OR=2.1, 95% CI: 1.4-3.0) did not have access to improved drinking water (OR=3.3, 95% CI: 1.9-5.9), and the toilet facility (OR=2.8, 95% CI, 1.9-4.3), while the children from district Nowshera (OR=1.7, 95% CI: 0.9-3.2) were significantly (P<0.05) associated in univariate analysis. The regression model revealed that child age, maternal age, family type, quality of water, and toilet facility, were the significant (P<0.05) factors contributing to child stunting in the flood-hit areas. Identification of key factors might be helpful for policymakers in designing comprehensive community-based programs for the reduction of stunting in flood-affected areas. In disasters such as flood, the detrimental consequences of the stunting problem could be even more on children. Evidence-based education and care must be provided to the families in the flood-affected regions to reduce the stunting problem. The determinants of stunting should [...].

A baixa estatura é um problema significativo de saúde pública em países de baixa e média renda. Este estudo avaliou a prevalência de nanismo e os fatores de risco associados de nanismo entre crianças em idade pré-escolar e em idade escolar em áreas afetadas por inundações do Paquistão. Foi realizado um estudo transversal visitando 656 domicílios por meio de amostragem em múltiplos estágios. As medidas antropométricas do entrevistado, informações sociodemográficas e instalações de saneamento foram exploradas. Um modelo de regressão logística foi usado para determinar os determinantes do nanismo, controlando todos os possíveis fatores de confusão. A prevalência geral de baixa estatura em crianças foi de 40,5%, entre as crianças 36,1% dos meninos e 46,3% das meninas com baixa estatura. A prevalência de baixa estatura em crianças menores de 5 anos foi de 50,7%. Crianças do sexo feminino (OR = 1,35, IC de 95%: 0,94-2,0), crianças de 13-24 meses (OR = 6,5, IC de 95%: 3,0-13,9), mães de 15-24 anos (OR = 4,4, IC de 95%: 2,6-7,2), família conjunta (OR = 2,1, IC 95%: 1,4-3,0) não tiveram acesso a água potável de qualidade (OR = 3,3, IC 95%: 1,9-5,9) e a banheiro (OR = 2,8, IC de 95%, 1,9-4,3), enquanto as crianças do distrito de Nowshera (OR = 1,7, IC de 95%: 0,9-3,2) foram significativamente (P < 0,05) associadas na análise univariada. O modelo de regressão revelou que a idade da criança, idade materna, tipo de família, qualidade da água e banheiro foram os fatores significativos (P < 0,05) que contribuíram para a baixa estatura infantil nas áreas afetadas pelas enchentes. A identificação de fatores-chave pode ser útil para os formuladores de políticas no planejamento de programas comunitários abrangentes para a redução da baixa estatura em áreas afetadas pelas enchentes. Em desastres como enchentes, as consequências prejudiciais do problema de baixa estatura podem [...].

Prevalence and determinants of stunting among preschool and school-going children in the flood-affected areas of Pakistan

Abstract Stunting is a significant public health problem in low- and middle-income countries. This study assessed the prevalence of stunting and associated risk factors of stunting among preschool and school-going children in flood-affected areas of Pakistan. A cross-sectional study was conducted by visiting 656 households through multi-stage sampling. Respondents anthropometric measurements, socio-demographic information and sanitation facilities were explored. A logistic regression model was used to determine determinants of stunting, controlling for all possible confounders. The overall prevalence of stunting in children was 40.5%, among children 36.1% boys and 46.3% of girls were stunted. The prevalence of stunting in under-five children was 50.7%. Female children (OR=1.35, 95% CI:0.94-2.0), children aged 13-24 months (OR=6.5, 95% CI: 3.0-13.9), mothers aged 15-24 years (OR=4.4, 95% CI: 2.6-7.2), joint family (OR=2.1, 95% CI: 1.4-3.0) did not have access to improved drinking water (OR=3.3, 95% CI: 1.9-5.9), and the toilet facility (OR=2.8, 95% CI, 1.9-4.3), while the children from district Nowshera (OR=1.7, 95% CI: 0.9-3.2) were significantly (P 0.05) associated in univariate analysis. The regression model revealed that child age, maternal age, family type, quality of water, and toilet facility, were the significant (P 0.05) factors contributing to child stunting in the flood-hit areas. Identification of key factors might be helpful for policymakers in designing comprehensive community-based programs for the reduction of stunting in flood-affected areas. In disasters such as flood, the detrimental consequences of the stunting problem could be even more on children. Evidence-based education and care must be provided to the families in the flood-affected regions to reduce the stunting problem. The determinants of stunting should be targeted by making comprehensive policies regarding proper nutrition, livelihood, clean water, and sanitation facilities in flood-hit regions.

Resumo A baixa estatura é um problema significativo de saúde pública em países de baixa e média renda. Este estudo avaliou a prevalência de nanismo e os fatores de risco associados de nanismo entre crianças em idade pré-escolar e em idade escolar em áreas afetadas por inundações do Paquistão. Foi realizado um estudo transversal visitando 656 domicílios por meio de amostragem em múltiplos estágios. As medidas antropométricas do entrevistado, informações sociodemográficas e instalações de saneamento foram exploradas. Um modelo de regressão logística foi usado para determinar os determinantes do nanismo, controlando todos os possíveis fatores de confusão. A prevalência geral de baixa estatura em crianças foi de 40,5%, entre as crianças 36,1% dos meninos e 46,3% das meninas com baixa estatura. A prevalência de baixa estatura em crianças menores de 5 anos foi de 50,7%. Crianças do sexo feminino (OR = 1,35, IC de 95%: 0,94-2,0), crianças de 13-24 meses (OR = 6,5, IC de 95%: 3,0-13,9), mães de 15-24 anos (OR = 4,4, IC de 95%: 2,6-7,2), família conjunta (OR = 2,1, IC 95%: 1,4-3,0) não tiveram acesso a água potável de qualidade (OR = 3,3, IC 95%: 1,9-5,9) e a banheiro (OR = 2,8, IC de 95%, 1,9-4,3), enquanto as crianças do distrito de Nowshera (OR = 1,7, IC de 95%: 0,9-3,2) foram significativamente (P 0,05) associadas na análise univariada. O modelo de regressão revelou que a idade da criança, idade materna, tipo de família, qualidade da água e banheiro foram os fatores significativos (P 0,05) que contribuíram para a baixa estatura infantil nas áreas afetadas pelas enchentes. A identificação de fatores-chave pode ser útil para os formuladores de políticas no planejamento de programas comunitários abrangentes para a redução da baixa estatura em áreas afetadas pelas enchentes. Em desastres como enchentes, as consequências prejudiciais do problema de baixa estatura podem ser ainda maiores para as crianças. Educação baseada em evidências e cuidados deve ser fornecida às famílias nas regiões afetadas pelas enchentes para reduzir o problema de nanismo. Os determinantes do retardo de crescimento devem ser almejados pela formulação de políticas abrangentes sobre nutrição adequada, meios de subsistência, água potável e instalações de saneamento nas regiões afetadas pelas enchentes.

Prevalence and determinants of stunting among preschool and school-going children in the flood-affected areas of Pakistan / Prevalência e determinantes da baixa estatura entre crianças em idade pré-escolar e em idade escolar nas áreas afetadas pelas enchentes do Paquistão

Stunting is a significant public health problem in low- and middle-income countries. This study assessed the prevalence of stunting and associated risk factors of stunting among preschool and school-going children in flood-affected areas of Pakistan. A cross-sectional study was conducted by visiting 656 households through multi-stage sampling. Respondent's anthropometric measurements, socio-demographic information and sanitation facilities were explored. A logistic regression model was used to determine determinants of stunting, controlling for all possible confounders. The overall prevalence of stunting in children was 40.5%, among children 36.1% boys and 46.3% of girls were stunted. The prevalence of stunting in under-five children was 50.7%. Female children (OR=1.35, 95% CI:0.94-2.0), children aged 13-24 months (OR=6.5, 95% CI: 3.0-13.9), mothers aged 15-24 years (OR=4.4, 95% CI: 2.6-7.2), joint family (OR=2.1, 95% CI: 1.4-3.0) did not have access to improved drinking water (OR=3.3, 95% CI: 1.9-5.9), and the toilet facility (OR=2.8, 95% CI, 1.9-4.3), while the children from district Nowshera (OR=1.7, 95% CI: 0.9-3.2) were significantly (P<0.05) associated in univariate analysis. The regression model revealed that child age, maternal age, family type, quality of water, and toilet facility, were the significant (P<0.05) factors contributing to child stunting in the flood-hit areas. Identification of key factors might be helpful for policymakers in designing comprehensive community-based programs for the reduction of stunting in flood-affected areas. In disasters such as flood, the detrimental consequences of the stunting problem could be even more on children. Evidence-based education and care must be provided to the families in the flood-affected regions to reduce the stunting problem. The determinants of stunting should be targeted by making comprehensive policies regarding proper nutrition, livelihood, clean water, and sanitation facilities in flood-hit regions.

A baixa estatura é um problema significativo de saúde pública em países de baixa e média renda. Este estudo avaliou a prevalência de nanismo e os fatores de risco associados de nanismo entre crianças em idade pré-escolar e em idade escolar em áreas afetadas por inundações do Paquistão. Foi realizado um estudo transversal visitando 656 domicílios por meio de amostragem em múltiplos estágios. As medidas antropométricas do entrevistado, informações sociodemográficas e instalações de saneamento foram exploradas. Um modelo de regressão logística foi usado para determinar os determinantes do nanismo, controlando todos os possíveis fatores de confusão. A prevalência geral de baixa estatura em crianças foi de 40,5%, entre as crianças 36,1% dos meninos e 46,3% das meninas com baixa estatura. A prevalência de baixa estatura em crianças menores de 5 anos foi de 50,7%. Crianças do sexo feminino (OR = 1,35, IC de 95%: 0,94-2,0), crianças de 13-24 meses (OR = 6,5, IC de 95%: 3,0-13,9), mães de 15-24 anos (OR = 4,4, IC de 95%: 2,6-7,2), família conjunta (OR = 2,1, IC 95%: 1,4-3,0) não tiveram acesso a água potável de qualidade (OR = 3,3, IC 95%: 1,9-5,9) e a banheiro (OR = 2,8, IC de 95%, 1,9-4,3), enquanto as crianças do distrito de Nowshera (OR = 1,7, IC de 95%: 0,9-3,2) foram significativamente (P < 0,05) associadas na análise univariada. O modelo de regressão revelou que a idade da criança, idade materna, tipo de família, qualidade da água e banheiro foram os fatores significativos (P < 0,05) que contribuíram para a baixa estatura infantil nas áreas afetadas pelas enchentes. A identificação de fatores-chave pode ser útil para os formuladores de políticas no planejamento de programas comunitários abrangentes para a redução da baixa estatura em áreas afetadas pelas enchentes. Em desastres como enchentes, as consequências prejudiciais do problema de baixa estatura podem ser ainda maiores para as crianças. Educação baseada em evidências e cuidados deve ser fornecida às famílias nas regiões afetadas pelas enchentes para reduzir o problema de nanismo. Os determinantes do retardo de crescimento devem ser almejados pela formulação de políticas abrangentes sobre nutrição adequada, meios de subsistência, água potável e instalações de saneamento nas regiões afetadas pelas enchentes.

Specific binding of aspartic protease and enterocytes promotes Trichinella spiralis invasion of murine intestinal epithelium cells

@#Trichinella spiralis is an important foodborne zoonotic parasite and it is necessary to develop vaccine to prevent T. spiralis infection in food animals. T. spiralis aspartic protease-2 (TsASP2) has been demonstrated to play a crucial role in larval invasion of intestinal epithelium cells (IECs). The purpose of this study was to assess the interaction between TsASP2 and IECs and to investigate the immune protection elicited by vaccination with rTsASP2. The results showed that the enzymatic activity of native aspartic protease was detected in crude proteins of all T. spiralis development stages other than NBL stage, the highest activity was observed in the IIL stage. The results of Western blot showed that TsASP2 protein was expressed at ML, IIL and AW but not NBL, and the TsASP2 expression level at IIL stage was significantly higher than those of other three worm stages (P < 0.05). The specific binding between rTsASP2 and IECs was observed by immunofluorescence test (IFT) and confocal microscopy, and the binding site was localized at the IEC membrane and this binding ability was inhibited by aspartic protease specific inhibitor pepstain A. The results of ELISA showed that the binding ability was protein dose-dependent. Vaccination with rTsASP2 triggered a mixed Th1/Th2 humoral and mucosal immune responses, as demonstrated by the elevation levels of Th1/Th2 cytokines (IFN-γ and IL-4) secreted by the spleen and mesenteric lymph nodes (MLNs) of immunized mice. The mice vaccinated with rTsASP2 exhibited a 54.17% reduction in enteral adult worms and a 54.58% reduction in muscle larvae after T. spiralis challenge. The results demonstrated that TsASP2 might be a potential molecular target for anti-Trichinella vaccines.

MicroRNA-340-5p modulates cisplatin resistance by targeting LPAATβ in osteosarcoma

MicroRNAs (miRNAs) play an important role in drug resistance and modulate the efficiency of chemotherapy. A recent study indicated that miR-340 functions as a tumor suppressor in various types of cancer. However, the role of miR-340 in chemotherapy has not been reported yet. In this study, we found that miR-340 enhanced cisplatin (CDDP)-induced cell death. Induction of miR-340-5p expression decreased the IC50 of CDDP and increased the apoptosis of CDDP-resistant MG-63 and Saos-2 cells. Moreover, miR-340-5p decreased the accumulation of MRP1 and MDR1. We further explored the mechanism underlying the promoting effects of miR-340-5p on CDDP-induced cell death. We identified a potential target of miR-340 in the 3′ untranslated region of lysophosphatidic acid acyltransferase (LPAATβ) using the online program Targetscan (http://www.microrna.org). Luciferase reporter assays showed that miR-340 binds to the 3′UTR of LPAATβ. Enforced expression of miR-340-5p decreased the accumulation of LPAATβ in both MG-63 and Saos-2 cells. Silencing LPAATβ decreased the IC50 of CDDP and increased the apoptosis of CDDP-resistant MG-63 and Saos-2 cells, which is consistent with the effect of miR-340-5p on CDDP-induced cell death. Moreover, induced expression of LPAATβ compromised the effects of miR-340-5p on CDDP-induced cell death and accumulation of MRP1 and MDR1. Taken together, our data indicated that miR-340-5p enhanced the sensitivity to CDDP by targeting LPAATβ.

Effects of perinatal exposure to nonylphenol on delivery outcomes of pregnant rats and inflammatory hepatic injury in newborn rats

The current study aimed to investigate the effects of perinatal exposure to nonylphenol (NP) on delivery outcome of pregnant rats and subsequent inflammatory hepatic injury in newborn rats. The pregnant rats were divided into 2 groups: control group (corn oil) and NP exposure group. Thirty-four pregnant rats were administered NP or corn oil by gavage from the sixth day of pregnancy to 21 days postpartum, with blood samples collected at 12 and 21 days of pregnancy and 60 days after delivery. The NP concentration was measured by HPLC, with chemiluminescence used for detection of estrogen and progesterone levels. Maternal delivery parameters were also observed. Liver and blood of the newborn rats were collected and subjected to automatic biochemical detection of liver function and blood lipid analyzer (immunoturbidimetry), and ultrastructural observation of the hepatic microstructure, with the TNF-α and IL-1β hepatic tissue levels evaluated by immunohistochemistry. Compared with the control group, the pregnant and postpartum serum NP and estradiol levels of the mother rats in the NP group were significantly increased, together with lowered progesterone level, increased number of threatened abortion and dystocia, and fewer newborn rats and lower litter weight. Serum and hepatic NP levels of the newborn rats measured 60 days after birth were significantly higher than those of the control group, as well as lower testosterone levels and increased estradiol levels. When observed under electron microscope, the hepatocyte nuclei of the control group were large and round, with evenly distributed chromatin. The chromatin of hepatocytes in the NP group presented deep staining of the nuclei, significant lipid decrease in the cytoplasm, and the majority of cells bonded with lysate. The results of immunohistochemistry showed that there was almost no TNF-α or IL-1β expression in the hepatocytes of the control group, while the number of TNF-α-, PCNA-, and IL-1β-positive cells in the NP group was increased, with higher integral optical density than the control group. Compared to the control group, the serum levels of alanine aminotransferase, aspartate aminotransferase, triglyceride and low-density lipoprotein in the newborn rats of the NP group were significantly increased. There was no significant difference in the serum level of high-density lipoprotein or cholesterol between the groups. Perinatal exposure to NP can interfere with the in vivo estrogen and progesterone levels of pregnant rats, resulting in threatened abortion, dystocia and other adverse delivery outcomes. High liver and serum NP levels of the newborn rats led to alteration of liver tissue structure and function. The NP-induced hepatotoxicity is probably mediated by inflammatory cytokines TNF-α and IL-1α.

Implantation of muscle satellite cells overexpressing myogenin improves denervated muscle atrophy in rats

This study evaluated the effect of muscle satellite cells (MSCs) overexpressing myogenin (MyoG) on denervated muscle atrophy. Rat MSCs were isolated and transfected with the MyoG-EGFP plasmid vector GV143. MyoG-transfected MSCs (MTMs) were transplanted into rat gastrocnemius muscles at 1 week after surgical denervation. Controls included injections of untransfected MSCs or the vehicle only. Muscles were harvested and analyzed at 2, 4, and 24 weeks post-transplantation. Immunofluorescence confirmed MyoG overexpression in MTMs. The muscle wet weight ratio was significantly reduced at 2 weeks after MTM injection (67.17±6.79) compared with muscles injected with MSCs (58.83±5.31) or the vehicle (53.00±7.67; t=2.37, P=0.04 and t=3.39, P=0.007, respectively). The muscle fiber cross-sectional area was also larger at 2 weeks after MTM injection (2.63×103±0.39×103) compared with MSC injection (1.99×103±0.58×103) or the vehicle only (1.57×103±0.47×103; t=2.24, P=0.049 and t=4.22, P=0.002, respectively). At 4 and 24 weeks post-injection, the muscle mass and fiber cross-sectional area were similar across all three experimental groups. Immunohistochemistry showed that the MTM group had larger MyoG-positive fibers. The MTM group (3.18±1.13) also had higher expression of MyoG mRNA than other groups (1.41±0.65 and 1.03±0.19) at 2 weeks after injection (t=2.72, P=0.04). Transplanted MTMs delayed short-term atrophy of denervated muscles. This approach can be optimized as a novel stand-alone therapy or as a bridge to surgical re-innervation of damaged muscles.

Rabbit nucleus pulposus cells facilitate differentiation of adipose‑derived stem cells into nucleus pulposus‑like cells.

OBJECTIVE: To investigate the feasibility of inducing adipose‑derived stem cells (ADSCs) to nucleus pulposus cells (NPCs). MATERIALS AND METHODS: ADSCs were isolated from rabbit while NPCs were isolated from an allogeneic rabbit. NPCs were co‑cultured with the 3rd generation ADSCs in co‑cultured system. Only NPCs were cultured in single culturing group. Through the collagen type II collagen immunohistochemistry, we observed NPCs and then identify NPC. Proteoglycan messenger RNA (mRNA) and collagen type II mRNA level were measured by real‑time polymerase chain reaction. RESULTS: In two group cells, collagen type II collagen were detected by immunohistochemistry. The amount of proteoglycan mRNA and collagen type II mRNA was both significantly higher in co‑cultured group than in single cultured group. CONCLUSIONS: In some condition, ADSCs have the potency to differentiate toward nucleus pulposus‑like cells. ADSCs are better seed cells for tissue engineering of artificial nucleus pulposus.

CTLA4 enhances the osteogenic differentiation of allogeneic human mesenchymal stem cells in a model of immune activation

Allogeneic mesenchymal stem cells (allo-MSCs) have recently garnered increasing interest for their broad clinical therapy applications. Despite this, many studies have shown that allo-MSCs are associated with a high rate of graft rejection unless immunosuppressive therapy is administered to control allo-immune responses. Cytotoxic T-lymphocyte-associated protein 4 (CTLA4) is a co-inhibitory molecule expressed on T cells that mediates the inhibition of T-cell function. Here, we investigated the osteogenic differentiation potency of allo-MSCs in an activated immune system that mimics the in vivo allo-MSC grafting microenvironment and explored the immunomodulatory role of the helper T cell receptor CTLA4 in this process. We found that MSC osteogenic differentiation was inhibited in the presence of the activated immune response and that overexpression of CTLA4 in allo-MSCs suppressed the immune response and promoted osteogenic differentiation. Our results support the application of CTLA4-overexpressing allo-MSCs in bone tissue engineering.

Propofol inhibits burn injury-induced hyperpermeability through an apoptotic signal pathway in microvascular endothelial cells

Recent studies have revealed that an intrinsic apoptotic signaling cascade is involved in vascular hyperpermeability and endothelial barrier dysfunction. Propofol (2,6-diisopropylphenol) has also been reported to inhibit apoptotic signaling by regulating mitochondrial permeability transition pore (mPTP) opening and caspase-3 activation. Here, we investigated whether propofol could alleviate burn serum-induced endothelial hyperpermeability through the inhibition of the intrinsic apoptotic signaling cascade. Rat lung microvascular endothelial cells (RLMVECs) were pretreated with propofol at various concentrations, followed by stimulation with burn serum, obtained from burn-injury rats. Monolayer permeability was determined by transendothelial electrical resistance. Mitochondrial release of cytochrome C was measured by ELISA. Bax and Bcl-2 expression and mitochondrial release of second mitochondrial-derived activator of caspases (smac) were detected by Western blotting. Caspase-3 activity was assessed by fluorometric assay; mitochondrial membrane potential (Δψm) was determined with JC-1 (a potential-sensitive fluorescent dye). Intracellular ATP content was assayed using a commercial kit, and reactive oxygen species (ROS) were measured by dichlorodihydrofluorescein diacetate (DCFH-DA). Burn serum significantly increased monolayer permeability (P<0.05), and this effect could be inhibited by propofol (P<0.05). Compared with a sham treatment group, intrinsic apoptotic signaling activation - indicated by Bax overexpression, Bcl-2 downregulation, Δψm reduction, decreased intracellular ATP level, increased cytosolic cytochrome C and smac, and caspase-3 activation - was observed in the vehicle group. Propofol not only attenuated these alterations (P<0.05 for all), but also significantly decreased burn-induced ROS production (P<0.05). Propofol attenuated burn-induced RLMVEC monolayer hyperpermeability by regulating the intrinsic apoptotic signaling pathway.

Detection of acute cerebral hemorrhage in rabbits by magnetic induction

Acute cerebral hemorrhage (ACH) is an important clinical problem that is often monitored and studied with expensive devices such as computed tomography, magnetic resonance imaging, and positron emission tomography. These devices are not readily available in economically underdeveloped regions of the world, emergency departments, and emergency zones. We have developed a less expensive tool for non-contact monitoring of ACH. The system measures the magnetic induction phase shift (MIPS) between the electromagnetic signals on two coils. ACH was induced in 6 experimental rabbits and edema was induced in 4 control rabbits by stereotactic methods, and their intracranial pressure and heart rate were monitored for 1 h. Signals were continuously monitored for up to 1 h at an exciting frequency of 10.7 MHz. Autologous blood was administered to the experimental group, and saline to the control group (1 to 3 mL) by injection of 1-mL every 5 min. The results showed a significant increase in MIPS as a function of the injection volume, but the heart rate was stable. In the experimental (ACH) group, there was a statistically significant positive correlation of the intracranial pressure and MIPS. The change of MIPS was greater in the ACH group than in the control group. This high-sensitivity system could detect a 1-mL change in blood volume. The MIPS was significantly related to the intracranial pressure. This observation suggests that the method could be valuable for detecting early warning signs in emergency medicine and critical care units.

Border malaria in Yunnan, China.

Yunnan Province, due its international borders with Myanmar, Vietnam and Lao PDR has a large number of imported cases of malaria, including a high proportion of Plasmodium falciparum, as a result of the mobility of the population. This movement is due to workers coming from other provinces where there is no malaria to work in the productive tropical lowlands. Chinese nationals who have gone to work in neighboring countries, border trade and refugees from Myanmar. Much of Yunnan is peopled by ethnic minorities living in remote mountainous and forested areas which are difficult to reach. However, surveillance has been strengthened by training 3,900 primary health care workers and combining the search for visiting foreigners, returning Chinese and people from other provinces with public security, customs formalities and employers. Any visitor detected by these services is obliged to have a blood slide taken. This has resulted in an earlier and more complete detection of malaria cases, reducing incidence from 19.19 to 12.12/10,000 in the border area over the last 10 years. This is despite a considerable increase in population movement and the threat of drug resistant malaria.

Genetic differentiation among three populations of Anopheles minimus of Guangxi and Yunnan Provinces in the People's Republic of China.

Electrophoretic studies were carried out on isozymes of 3 populations of Anopheles minimus collected from Guangxi and Yunnan Provinces of the People's Republic of China in 1993. Eight proteins were analyzed by 5% polyacrylamide gel electrophoresis. The most variable population, 'Yunnan-Field' (Y-F), was highly polymorphic at 14 of 20 loci (P = 0.700) with an average heterozygosity H of 0.340. P values of 0.500 and 0.700, and H values of 0.220 and 0.210 were obtained for each from 'Guangxi-Lab' (GX-L) and 'Yunnan-Lab' (Y-L), respectively, Nei's genetic distances (D) between Y-L and GX-L, Y-F and GX-L, and Y-F and Y-L were 0.1131, 0.1946 and 0.1069, respectively. These results suggest that GX-L is distant from the 2 other populations, Y-L and Y-F, and that this genetic differentiation between the 2 populations of Yunnan and Guangxi Provinces corresponds to the forms A and B, which were morphologically classified by Xu et al (unpublished).

Genetic differentiation among three populations of Anopheles minimus of Guangxi and Yunnan Provinces in the People's Republic of China.

Electrophoretic studies were carried out on isozymes of 3 populations of Anopheles minimus collected from Guangxi and Yunnan Provinces of the People's Republic of China in 1993. Eight proteins were analyzed by 5% polyacrylamide gel electrophoresis. The most variable population, Y-F, was highly polymorphic at 14 of 20 loci (P=0.700) with an average heterozygosity H of 0.340. P values of 0.500 and 0.700, and H values of 0.220 and 0.210 were obtained for each from 'Guangxi-Lab' (GX-L) and 'Yunnan-Lab' (Y-L), respectively. Nei's genetic distances (D) between Y-L and GX-L, Y-F and GX-L, and Y-F and Y-L were 0.1131, 0.1946 and 0.1069, respectively. These results suggest that GX-L is distant from the 2 other populations, Y-L and Y-F, and that this genetic differentiation between the 2 populations of Yunnan and Guangxi Provinces corresponds to the forms A and B, which were morphologically classified by Xu et al (unpublished).

Seroprevalence and risk factors of human cysticercosis in a community of Shandong, China.

A community-based seroepidemiologic survey on Taenia solium cysticercosis in humans was carried out in Shandong Province, China. Blood specimens from 2,898 residents were collected and examined for anti-cysticercus antibody. Information on demographic and potential risk factors was obtained using a standardized questionnaire. The overall seroprevalence of cysticercosis was 3.2%. Seropositivity tended to increase with age ranging from 1.8% in children under 6 years of age to 5.7% in those over 60 years old. Distance between village residence and the town of the community was negatively associated with seropositivity (Chi-square for trend test p = 0.02). Multivariate logistic regression analysis identified four risk factors for cysticercosis infection in the community: defecating indiscriminately (OR = 1.35, 95% CI 1.01-1.81), being unable to identify diseased pork (OR = 4.09, 95% CI 1.53-10.97), raising pigs (OR = 1.36, 95% CI 1.09-1.69), and more than 60 years old (OR = 1.49, 95% CI 1.10-2.02. These findings have implications for developing appropriate strategies for the control of Taenia solium cysticercosis in the community.

Effects of Brugia malayi infection on the survival of Anopheles sinensis.

Effect of different numbers of infecting Brugia malayi on the survival of Anopheles sinensis were quantitatively studied in our laboratory. Four groups of healthy adult female mosquitos were tested. They were named G-0, G-1, G-2 and G-3, in which the numbers of microfilariae (mf) infecting per mosquito were 0, 5, 10 and 50, respectively. The experimental infection was conducted by inoculating the mf into the bodies of mosquitos through the neck membrane with a microinjector. It was observed that, in the groups from G-0 to G-3, the maximal life-span postinoculation (PI) were 21, 21, 20 and 10 days, the average life-spans PI were 7.78, 7.98, 7.05 and 3.55 days, and the survival time at 50% mortality PI were 6.72, 6.80, 6.40 and 4.00 days, respectively. Daily survival rates in the groups G-0, G-1 and G-2 declined slowly, over 25% on the 10th day PI, whereas the one in the group G-3 dropped down quickly, to zero on the same day. Linear regression analysis on the daily survival rates against the days PI showed significant differences between the groups G-0 and G-3 (0.02 > p > 0.01), but no significant differences between the groups G-0 and G-1, or between G-0 and G-2 (p > 0.5).

Epidemiological surveillance of filariasis after its control in Shandong Province, China.

Shandong Province used to be the highly endemic area of Wuchereria bancrofti. Culex pipiens pallens was the main mosquito vector. After about 30 years of large scale anti-filariasis control campaign, filariasis was controlled throughout the province in 1983. Since then, extensive cross-sectional and consecutive longtitudinal surveillances have been carried out. Parasitological and entomological data indicated that the microfilaremia rate of the human population, and the natural infection rate of mosquito vector kept declining, with many villages dropping to zero; no children under ten were infected. Serological surveillance showed that antifilarial antibody had fallen to the same level as that in non-endemic areas 10-15 years after control. In addition, patients with chronic manifestations were reduced in number. It is suggested that the achievement in filariasis control in Shandong Province is stable: the transmission of filariasis has been interrupted. However, there are still a few residual microfilaremia cases, which may bring about new infection under conditions favorable for transmission. Infectious sources may be introduced by population movements from a neighboring province where filariasis is still endemic at present. Moreover, new cases with chronic manifestations, especially chyluria, continually emerge. So systematic surveillance should be continued and proper control measures must be taken to eventually wipe the disease out of the province.

The adverse effect of marginally higher lead level on intelligence development of children: a Shanghai study.

We surveyed 128 preschool children in a lead-polluted area in Shanghai to study the relationship between blood lead level and neuropsychological functions, assessed by age-appropriate psychological tests. The geometric means of blood lead level was 21.7 + -10.8 micrograms/dl. Of 47 children aged below 30 months, there was no significant difference in BSID indices between the high and low lead subjects, although the high lead children tended to have poorer development scores than the low lead ones. On the other hand, of 81 children older than 46 months, the WPPSI IQ scores showed highly significant negative correlation with blood lead level. Step-wise regression and multiple analysis of covariance techniques were employed to find out and control the confounding factors. Even when 21 non-lead variables were considered, the IQ difference between high and low lead groups remained statistically significant. We concluded that the children, especially those older than 46 months, in the area investigated, did suffer from lead toxicity causing impairment in intelligence development. We support the view that marginally higher lead level in children should be taken seriously.

Quantitative studies on the development of inoculated Brugia malayi microfilariae in Anopheles sinensis and Culex quinquefasciatus.

Definite numbers of B. malayi mf were inoculated into An. sinensis and Cx. quinquefasciatus, and their subsequent development was observed. The relationships between the dosage and the L3 positive rate on the one hand and the average filarial maturity rate on the other were defined. At the same dosages of 4 and 10 mf/mosquito, the L3 positive rates and the average filarial maturity rates in An. sinensis were much higher than those in Cx. quinquefasciatus (p less than 0.01). It was demonstrated that the immune response to filariae of the mosquitos was the main factor resulting in these differences. The intensity of the immune response not only varied with the species, but also declined with the aging of mosquitos. The results of our experiment might be useful to studies on the dynamics of filariasis transmission and the interaction between filariae and their insect hosts.