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H Zhou

Publications and source records attributed to H Zhou.

679 records · Page 38Linked to original sources
PubMedDate not supplied

Classification, follow-up and recurrence of hepatic cystic echinococcosis using ultrasound images.

Ultrasound image and morphological structure of hepatic cystic echinococcosis (CE) were analysed in 277 human cases (385 hepatic hydatid cysts). These included 65 CE cases from community surveys carried out between 1995 and 2000 in 3 countries (China, Mongolia and Jordan) and 212 cases from a clinical hospital survey from Xinjiang, China. A new simplified WHO ultrasound classification for human CE was assessed, and considered useful. It is proposed that type, size and number in particular need to be included in the ultrasound classification of hepatic CE. For comparative purposes 6 categories of type were classified in the study as Type 0 to Type 5 (T0-T5): T0, univesicular without pathognomonic signs; T1, univesicular with pathognomonic signs; T2, cysts with sagging or floating laminated membrane; T3, cysts containing daughter cysts; T4, solid mass or mixed cysts; and T5, cysts with partial or full calcifications. This differs from the WHO classification wherein Type T3 cysts (daughter cysts present) are considered a pathological stage to occur in general prior to the sagging or floating membrane (T2) stage. Recurrent hydatid cysts in the liver were also studied based on morphological structures observed directly from surgical intervention. Case follow-up over 1-5 years since endocystectomy in the community surveys indicated 10% (2/10) recurrence of cysts in the residual surgical cavity. Recurrent CE included 2 (2/4) cases after percutaneous treatment.

China↗
PubMedDate not supplied

Diagnosis of schistosomiasis japonica in Chinese schoolchildren by administration of a questionnaire.

This paper describes a rapid, simple, cost-effective questionnaire for screening school-aged children at risk for Asian schistosomiasis in China. Five hundred and thirty-two children, aged 8-14 years, were selected from 3 schools in an area moderately endemic for Schistosoma japonicum in Hunan province. The questionnaire, comprising 15 multiple-choice questions, was administered by teachers in order to collect both ethnographic and epidemiological data relevant to current S. japonicum infections. This was followed by Kato-Katz thick smear stool examinations, miracidium hatching tests, and soluble egg antigen-enzyme linked immunosorbent assays in order to validate the efficacy of the questionnaire approach. The results from a combination of all 3 procedures indicated that the overall schistosomiasis prevalence in the 3 schools was 29.9% (138/472). Six risk factors (episodes of diarrhoea, frequency of water contact, school grade attained, weakness, past history of S. japonicum infection(s), and whether a subject had been previously treated for schistosomiasis) in the questionnaire were determined by logistic regression to be highly statistically significant predictors of individual current infection. The sensitivity (93.7%), specificity (91.9%) and low cost (c. US$ 0.6/true positive case) associated with the 6 variables model make the questionnaire approach a very useful diagnostic tool for screening marshland and lake communities at high risk for schistosomiasis in China before selective treatment with praziquantel or diagnostic follow-up. An even simpler 3 variables 'yes/no' model was derived from the questionnaire and found to be nearly as good at predicting individual infection (sensitivity 86.2% and specificity exceeding 97.6%) and extremely simple to use. If validated in other ecological settings in China the questionnaire, modified or as presented here, could be adopted by the national schistosomiasis control programme.

Adolescent↗
PubMedDate not supplied

Pharmacokinetic profile of cisapride 20 mg after once- and twice-daily dosing.

Cisapride is a substituted piperidinyl benzamide. It is chemically related to metoclopramide but lacks the antidopaminergic properties of metoclopramide that affect the central nervous system and cause extrapyramidal side effects. Cisapride is indicated for the symptomatic treatment of patients with nocturnal heartburn due to gastroesophageal reflux disease. Based on extensive assessment of the drug's pharmacokinetic profile, the currently approved initial oral dosing regimen for cisapride is 10 mg QID. However, the pharmacokinetics of cisapride after oral administration of 20 mg BID have not been investigated. We present here findings from an open-label trial assessing the pharmacokinetics of cisapride 20-mg tablets after a single dose and at steady state (BID dosing). The results indicate that 20-mg BID and 10-mg QID regimens produce similar steady-state concentrations.

Adult↗
PubMedDate not supplied

Development of the neuromuscular junction: genetic analysis in mice.

Formation of the skeletal neuromuscular junction is a multi-step process that requires communication between the nerve and muscle. Studies in many laboratories have led to identification of factors that seem likely to mediate these interactions. 'Knock-out' mice have now been generated with mutations in several genes that encode candidate transsynaptic messengers and components of their effector mechanisms. Using these mice, it is possible to test hypotheses about the control of synaptogenesis. Here, we review our studies on neuromuscular development in mutant mice lacking agrin alpha CGRP, rapsyn, MuSK, dystrophin, dystrobrevin, utrophin, laminin alpha 5, laminin beta 2, collagen alpha 3 (IV), the acetylcholine receptor epsilon subunit, the collagenous tail of acetylcholinesterase, fibroblast growth factor-5, the neural cell adhesion molecule, and tenascin-C.

Agrin↗
PubMedDate not supplied

Model-based approaches to studying fertility and contraceptive efficacy.

Statistical methods recently developed to aid in identifying environmental exposures with reproductive toxicity can also be applied to trials of interventions undertaken specifically to impair fertility, i.e. methods of contraception. Although only applicable in a trial that includes a reliable benchmark for identifying the day of ovulation, the proposed measures of contraceptive efficacy derived from such a trial offer certain interpretive advantages over the more traditional approaches of evaluating contraceptives. Extensions of the same models also allow one to evaluate efficacy under any assumed pattern of imperfect use. One can also evaluate methods based on biomarkers for the fertile phase of the cycle, such as hydration of the cervical mucus, that may prove to be enormously helpful to couples who wish to use periodic abstinence as their method. In prospective studies of fertility, couples who occasionally use a barrier method should not be excluded from the study, but can be retained, without biasing the estimates for fertility parameters.

Contraception↗
PubMedDate not supplied

Near-field mapping of the emission distribution in semiconductor microdiscs.

We have used a scanning near-field optical microscope to study the fluorescent light distribution in the near- and far-fields with two types of microdiscs, InGaP and GaN, fabricated in our laboratory. The InGaP microdisc has a radius of 2.5-5.0 microm, a thickness of 0.15-0.2 microm and a circular shape and the GaN disc has a radius of 5-8 microm with a thickness of 0.5-2 microm. Spontaneous emission enhancement in these microdiscs has been observed with emitting wavelengths of 650 and 550 nm respectively In both types of microdisc, the whispering-gallery mode (WCM) has been observed on the top surface using near-field optical and far-field microscopic methods. However, due to the different disc structures and optical confinements, the light distributions of the type types of disc are quite different. In the case of the InGaP disc, WGM is the dominant mode with a mixture of other modes. Interference-like ring intensities have been observed both inside the disc surface and outside, with a period ratio of 1:2. In addition, the propagating waves emitted from the side of the disc have been collected for the first time by using near-field optical microscopy. A theoretical calculation based on the theory of optical modes in microdisc lasers confirmed this observation. It also predicted the behaviour of the electric field distribution (transverse electric) inside and outside the disc, as well as the period of the wave propagation. In contrast, the near-field mapping of the GaN fluorescence showed not only a ring-like emission intensity along the circumference of the disc, an indication of WGM, but also an even intensity distribution inside the disc. This can be explained as the combination of the WGM with the Fabry-Perot mode of multi-reflection between the GaN layer and the substrate. The results also demonstrate the potential application of near-field optics to explore the light emission mode of a microdisc on a nanometre scale.

Journal Article↗
PubMedDate not supplied

The CEA family: a system in transitional evolution?

The CEA family consists of two structurally and functionally distinct sub-groups; the group including CEA, NCA and CGM-6 which are cell surface-bound by phosphatidyl-inositol (PI) linkages, and the group of BGP splice variants which have trans-membrane and cytoplasmic domains. Although all CEA family members mediate intercellular adhesion in vitro, the PI-linked group show Ca++ and temperature independent adhesion whereas the BGP group show rapidly reversible Ca++ and temperature dependent adhesion. From the close alignment in cDNA nucleotide sequences between family members and between repeated domains in one family member, it is apparent that the CEA family is now rapidly evolving; in fact, analogs of only the trans-membrane BGP group have been found so far in the mouse. The addition of a new group of potent adhesion molecules to complex species at some time after the rodent radiation has strong evolutional implications, which are discussed.

Animals↗
PubMedDate not supplied

Associations of interferon-gamma genotype and protein level with antibody response kinetics in chickens.

Although previous studies have demonstrated an association between interferon-gamma (IFN-gamma) promoter genotype and antibody response kinetics in chickens, the protein levels that may mediate such a gene-trait association have not been determined. The objective of this study, therefore, was to determine the correlation of circulating IFN-gamma levels with both the IFN-gammaIFN-gamma promoter polymorphisms and antibody response in order to evaluate the potential role of IFN-gamma protein in mediating genetic control of antibody response in chickens. Antibody response after Salmonella enteritidis (SE) vaccination at day 10, antibody response to sheep red blood cells (SRBCs) and killed Brucella abortus after immunizations at 19 wk and 22 wk, and serum IFN-gamma protein level were measured in an F2 population derived from inbred lines. A single nucleotide polymorphism in the IFN-gamma promoter region was associated with IFN-gamma protein expression as measured by an enzyme-linked immunosorbent assay after both primary and secondary immunizations. Higher IFN-gamma protein level was correlated with higher antibody level to SE and with increased maximum level and decreased time to reach the maximum secondary antibody response to SRBCs. These results suggest that one of the mechanisms by which promoter polymorphism of IFN-gamma affects antibody production in chickens may involve the circulating level of IFN-gamma protein.

Agglutination Tests↗
PubMedDate not supplied

Multiple macroregenerative nodules in liver cirrhosis due to Budd-Chiari syndrome. Case reports and review of the literature.

Clinical, radiological, histological and immunohistochemical methods were used to define the nature of multiple rapidly growing hepatic nodules in 2 young patients with Budd-Chiari syndrome due to myeloproliferative diseases. In one patient, the arterial hyperperfusion of large nodules was demonstrated by dynamic computed tomography and angiography. The explanted livers of these patients showed multiple well-demarcated nodules up to 3 cm in diameter on the background of liver cirrhosis resulting from chronic hepatic congestion. Histologically, these nodules covered a spectrum ranging from adenoma-like lesions to nodules resembling focal nodular hyperplasia. They consisted of essentially normal hepatocytes, and variably contained fibrous septa including neoductules and large, mostly dysmorphic arteries. Sometimes, they were located close to still patent or recanalized veins. These rapidly growing hepatic nodules are best defined as macroregenerative nodules. The knowledge of this entity may help the physician to avoid misinterpretation of such nodules as carcinomas.

Adolescent↗
PubMedDate not supplied

[Orthopedic aspects of osseous echinococcosis--radiologic diagnosis, current surgery and drug therapy aspects].

PURPOSE: Skeletal manifestation of alveolar (E. multilocularis) or cystic (E. granulosus) echinococcosis is seldom, with an incidence of less than 2% of all cases. By reporting on a rare case of bony manifestation of E. granulosus, we intend to emphasize current standards in surgical and drug management of the disease. Typical radiographic and blood-chemistry findings are highlighted on a 62-year-old Arabiqu female suffering from a cystic echinococcosis with skeletal manifestation in the left ileum and lower lumbar spine. RESULTS: Radiographically typical are fine zones of osteolysis which, at a later stage, show confluence. Due to the rigid structure of cortical bone, cysts tend to grow slowly, and seldom exceed 2 cm in diameter. Only after having broken through the cortical bone, may a massive increase in size be observed. By means of serological tests, it is postoperatively possible to evaluate how successful radical surgery with removal of larvae was. Furthermore, serological tests can be used as a screening method, offering a diagnostic tool that can also utilized in detecting a recurrence. CONCLUSION: The surgical aim in the treatment of osseous echinococcosis should be in accordance to curative tumor surgery. Even after radical removal of the parasites, the WHO suggests an adjuvant chemotherapy with mebendazole or albendazole for at least two years after surgery. In cases where only a palliative treatment is possible, the antihelminthic drug administration can be continuous.

Acetabulum↗
PubMedDate not supplied

Intercommunity differences in acid aerosol (H+)/sulfate (SO4(2-) ratios.

Exposures to acid aerosols have been associated with acute and chronic health effects. Beginning in 1988, extensive monitoring of acid aerosols (H+), sulfates (SO4(2-)), and ammonia (NH3) was conducted in 24 communities in the United States and Canada in order to characterize the seasonal and daily variations of these pollutants. More recently, in 1992 and 1993, summer monitoring of the same pollutants was conducted by Harvard researchers at multiple locations in Philadelphia, Pennsylvania to examine the factors causing spatial variation in the acidity levels in the greater metropolitan Philadelphia area. Earlier, a similar study also was conducted by Harvard in a more rural community, State College, Ohio, providing data on acidity, sulfate, and ammonia levels. In addition to these studies, New York University researchers have gathered substantial data on aerosol acidity, sulfates, and NH3 levels from sites in the New York City metropolitan region, Albany, Buffalo, and the Toronto metropolitan region between 1988 and 1992. This paper examines the relationships among H+, SO4(2-), ozone, and population density using summer measurements from sites in 24 cities across the United States and Canada, as well as Philadelphia, State College, the New York City region, Buffalo, and Albany. While past studies have consistently shown that H+ and SO4(2-) are correlated over time at sites in eastern North America, the results of our analysis show that spatial variations in the ratios of mean acid-to-sulfate levels also can be predicted satisfactorily with the use of either a linear or a quadratic model, once variations in population density are addressed (R2 = 0.6). These models may be useful in retrospective epidemiological investigations of acid aerosol exposures and health effects, using widely available sulfate measurements and data on local population size.

Acid Rain↗