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Biomedical subjects

W Zhou

Publications and source records attributed to W Zhou.

At least 271 records · Page 15Linked to original sources
PubMed1997

Gestational weight gain as a predictor of birth and placenta weight according to pre-pregnancy body mass index.

OBJECTIVE: To study the association between gestational weight gain and different birth weight indicators considering the pre-pregnancy body mass index. It was hypothesized that a high body mass index (BMI) would modify the effect of gestational weight gain and support the advice of keeping gestational weight gain at a moderate level in case of obesity. STUDY DESIGN: A follow-up study of consecutively recruited women in two well defined geographical areas in Denmark. The recruitment lasted from 1984 to 1987 and 11,850 pregnant women and newborns were included in the study. The remaining analyses were restricted to non-diabetic women who gave birth between weeks 37 and 42 of gestation for whom weight gain was reported-altogether 7,122 women. RESULTS: Birth and placenta weight were associated with gestational weight gain but with lower regression coefficients at higher BMI. The proportion of newborns with a birth weight of 4,500 grams or more increased with increasing gestational weight gain, especially in women with a BMI above 26. CONCLUSION: The potential benefit of a high gestational weight gain in obese patients should be balanced by the higher risk of giving birth to babies with a birth weight of more than 4,500 grams and the risk of exaggerating a pre-existing state of obesity.

Adult↗
PubMed1997

Evidence for increased synthesis of complement C4 in the renal epithelium of rats with passive Heymann nephritis.

Passive Heymann nephritis (PHN) is a complement-dependent model of immune complex glomerulonephritis. This study investigated the contribution of local complement synthesis by studying gene expression of the classical pathway component C4 in relation to the site of the tissue injury and the development of proteinuria induced by the pathogenic antibody (sheep anti-GP330). This study, using in situ hybridization, found that C4 mRNA expression was increased in the glomerular epithelium and the proximal renal tubular epithelium in a distribution similar to that of the targeted GP330 antigen. The total cortical C4 mRNA expression assessed by semiquantitative polymerase chain reaction (PCR) increased in a time-dependent manner (P < 0.05), coincident with the onset and progression of proteinuria, and peaking 11 to 14 days after the induction of the disease. These data suggest a link, in place and time, between local complement gene expression and glomerular barrier dysfunction induced by anti-GP330. It is postulated that increased epithelial synthesis of C4 stimulated by the engagement of GP330 enhances the formation of the membrane attack complex of complement through its classical pathway, and, hence, the formation of complement-mediated injury.

Animals↗
PubMed1997

[The ampullar endolymhatic potential in the guinea pigs].

The purpose of this paper is to understand the physiologic feature of the ampullar endolymphatic potential (AEP) in the guinea pigs (n = 35). The high input impedence microelectrode amplifier was used. The effects of asphyxia, furosemide and ischemia on the AEP were observed. The AEP was 4.55 +/- 1.35 mV, (n = 35) in normal. The potential decreased to 2.8 +/- 0.8 mV from the original level in two minutes of asphyxia. When the respirator was turned on the AEP started to rise abruptly after a latency. In all instances there was an overshoot above the preasphyxia level. When furosemide was administered i.v. at 100 mg/kg, no effects were seen in the AEP. After obstruction of the ascending aorta to cause ischemia, the AEP continued to decline until it reached a minimum of -19.4 +/- 1.7 mV in 52.5 +/- 9.6 minutes and slowly returned to zero line in about 150 minutes. There was no obovious effect after furosemide injection. The results suggest that AEP may deffer from as the positive potential in cochlea. It is produced in the specialized cells (dark cells) of the ampullar and has special electro-physiologic characteristics.

Action Potentials↗
PubMed1997

[Effect of furosemide on the ampullar endolymphatic potential and endolymphatic Ca2+ activity].

The ampullar endolymphatic potential (AEP) and the endolymphatic Ca2+ activity were measured with double-barred Ca2+ selective microelectrodes in the experimental hydrops of guinea pigs. They showed 3.16 +/- 0.42 mV (n = 9) and (4.10 +/- 1.22) x 10(-4) M, respectively. The AEP decreased significantly at about 6 min after intravenous administration of 10 mg/kg furosemide. Its minimal value was 3.04 +/- 0.53 mV at about 40 min. But there was no significant difference between that and the value before injection. The Ca2+ activity increased significantly and reached (7.10 +/- 1.32) x 10(-4) M at about 60 min. The changes indicate that Ca2+ may play an important role in the mechanism of the furosemide test.

Animals↗
PubMed1997

[Experimental study of myocardial myoglobin depletion induced by early myocardial infarction and coronary artery spasm].

In this study, the model of early myocardial infarction (EMI) was produced by legation of left anterior descending artery in rat. The artery spasm (CAS) was produced by external jugular vein injection of vasopressin (VP). Myocardium of apex and adjoining slice was used to make paraffin sections, then HE and LSAB-Mb staining were performed. Results showed: In 25 min after myocardial infarction, stretch-shape Mb depletion was observed in subendocardial myocardium of aortic ventricle's frontal wall. As the time of EMI prolonged, stretch-shape Mb depletion extended to epicardial layer. In CAS group, multiply, spotty Mb depletion was detected. There were more Mb depletion zones in right heart than that in left heart. The Mb depletion zones surrounded the CA or were like grape-clusters along the branches of one large CA. Thus, myocardial Mb depletion induced by EMI and CAS had different morphologic peculiarity. LSAB-Mb method could be hoped for the use of supplying objectively morphologic evidence to myocardial ischemia induced by CAS.

Animals↗
PubMed1997

[The use of microwave for immunohistochemical technology in forensic pathology].

A microwave oven (MWO) of National brand was applied for Labeled Streptavidin Biotin immunohistochemical staining (LSAB method) on autopsy materials of 20 cases to detect 10 kinds of antigen of heart and brain: The keys to manipulate MWO as follows: (1) Recovery of antigen: submerge sections in 0.01M citrate buffer (pH 6.0), turn MWO to the position of DEF (210W) for 10 min, reaching temperature 92 degrees C-98 degrees C. (2) add normal serum, first antibody, second biotinylated antibody and streptavidin complex, then turn MWO to the position of LOW (70W) for 5 min, reaching temperature 20 degrees C-37 degrees C. Other steps were the same as the standards. Results showed: MWO can recover the destroyed or covered antigen, improve positive staining degree, reduce background's stain and shorten staining time.

Antigens↗
PubMed1997

[Correlations between retinal fluorescein angiography and blood viscosity and other factors in patients with primary open angle glaucoma].

OBJECTIVE: To investigate the correlations between retinal fluorescein angiography and blood viscosity and other factors in patients with primary open angle glaucoma (POAG). METHODS: Multiple stepwise regression analysis was made to approach the correlation between each of the following blood vessel filling times: the arm-choroid (A-CT), arm-retinal artery (A-AT), and retinal artery-venous (A-VT) of the fundus fluorescein angiography (FFA) in 122 eyes with POAG and each of the following related factors in hemorheology: whole blood apparent viscosity at low, medium and high shear rates, plasma viscosity and hematocrit. Also, the same analysis was applied to investigate the correlation between each of the A-AT, A-VT of the FFA in 70 eyes with POAG and each of the following factors: systolic blood pressure, diastolic blood pressure, age and the whole blood apparent viscosity at low shear rate. RESULTS: The whole blood apparent viscosity at low shear rate was closely related to A-CT and A-AT, while hematocrit was closely related to A-VT of the FFA. The whole blood apparent viscosity at low shear rate and age, especially whole blood apparent viscosity, was closely related to A-AT, A-VT of the FFA. CONCLUSION: The blood viscosity can affect the filling times of the FFA in POAG.

Blood Viscosity↗
PubMed1997

[A comparative study of visual field defects between primary open-angle and low tension glaucoma].

OBJECTIVE: To investigate the characteristics of early visual field defects in primary opene-angle glaucoma (POAG) and low tension glaucoma (LTG). METHOD: The visual fields of 41 eyes with early POAG and 15 eyes with LTG were quantitatively measured with QZS-2 automated perimetry (full threshold program). RESULTS: Most of the early glaucomatous visual field defects in POAG and LTG presented the decrease of localized light sensitivity, and a few indicated the decrease of diffuse type. The defect occurred entirely in the central field and in a small number of eyes it was complicated by the peripheral field defect, especially in the nasal field. The differences of the mean light sensitivity and short-term fluctuation in the central field were statistically significant between the early POAG or LTG and the normal control group (all P < 0.05). In the comparisons of the visual field defect and retinal nerve fiber layer defect between early POAG and LTG groups, the results indicated that the types of damage and distribution of the areas involved were not different. CONCLUSION: The characteristics of early visual field defects in POAG and LTG are the same.

Adult↗
PubMed1997

[Sequence of HLA-DQA1 promoter region in the Han people].

Polymorphism of HLA-DQA1 promoter region (QAP) in the Han people has been identified. The results revealed a number of differences, some of which are in the critical class II boxes, and generally conserved in HLA-DQA1 promoter region. The major differences occurred in the X box, Y box and S box. Within the X box, the Hans carry a A at position -111, instead of a G, and a G or a A can be present at position -98. Within the S box, the Hans carry a G at position -131. Within the Y box, position -71 is a A rather than a G. Some single base substitutions have been detected from IDDM patients at the 5'-flanking region of the S box and between X box and Y box. Particularly, the insertion of CCA bases has been identified at the position between -157 and -158 in a IDDM patient. These data suggest that the polymorphism of HLA-DQA1 promoter region may play a role in susceptibility to IDDM.

Adult↗
PubMed1997

[Study on the association of HLA-DR4 with IDDM susceptibility in a Chinese population].

HLA-DR4 and its subtypes were studied by PCP/SSP, PCR/SSOP, and PCR/RFLP methods in 81 patients with IDDM and 106 normal controls in the Han's nationality Chinese population. The results showed no difference in frequencies of DR4 between the IDDM group and the controls (21.0% vs 17.9%), but DRB1*0405, as a subtype Dw15, was significantly associated with IDDM susceptibility (58.8% vs 21.1%, RR = 2.67, P < 0.05). In a family with 2 IDDM patients, it has been found the haplotype DRB1*0405-DQB1*0302 was to be cosegregated with IDDM. It was suggested that DW15 subtype might be associated with IDDM in Chinese because of linkage disequilibrium with DQw8 (DQB1*0302). As an additional evidence, the findings above mentioned may account for the different association of different DR4 subtypes with IDDM in various ethnic groups.

Adolescent↗
PubMed1997

Quantitative real time measurement of iris configuration in human eyes.

PURPOSE: To evaluate intraobserver and interobserver reproducibility of real time measurement of iris morphology in living human eyes. METHODS: Based on the platform of software (Autocad, version 12), we developed an ultrasound biomicroscopy (UBM) image assistant measuring system. By using the system, we can perform the iris configuration quantitative measurement in living eyes. The measuring parameters including: iris rest length, radius of iris curvature, and the thickness in different parts of iris. Ten anterior segment images of one normal individual were obtained by a single operator to evaluate the intraobserver reproducibility of image capture, and ten times measurement of one image were performed by a single operator to assess the reproducibility of image measurement. The measurement of three independent observers were compared to investigate interobserver reproducibility in quantitative measurement. Intraobserver and interobserver reproducibility of measurement were assessed by calculating the coefficient of variation for each individual observer and by using the F test to detect a difference among observers. The iris configuration of 96 subjects (192 eyes) were measured. RESULTS: Intraobserver reproducibility was ranged from 0.9-4.9% in all measured parameters. Interobserver reproducibility for some of measured parameters varied considerably and was affected by subjective interpretative of visualized anatomic landmarks. The preliminary measured parameters in Chinese Show that iris rest length is 3.699 +/- 0.397 mm, radius of iris curvature is 9.101 +/- 1.408 mm, the average thickness of iris is 0.406 +/- 0.042 mm. CONCLUSION: The intraobserver reproducibility and the measured accuracy can fit the requisition of the ocular biometry and of the ocular physiology, pathophysiology, and pharmacology study. The method supply a new assistance for UBM image measurement.

Adult↗
PubMed1997

[Expression of hepatitis B virus S genes in Ad5 vector].

The hepatitis B virus (HBV) S gene, PreS2 + S genes and the late phase expression cassette (MTI) + HBV S genes were separately cloned into Ad5 vector downstream of E3 promoter (pAd5 deltaE3 provided by Wyeth Co.). The above constructed plasmids and Ad5 DNA EcoR I A fragment were cotransfected into 293 cells. The progeny adenoviruses named rAd5S, rAd5MS, rAd5S2S were harvested for analysis. The recombinants were isolated and analyzed by PCR, using two primers specific to the HBV S genes. The expressed products were detected by ELISA and RIA. The recombinant containing MIT + HBV S genes (rAd5MS) was identified to be ELISA positive, whereas the other two recombinants (rAd5S, rAd5S2S) were negative to ELISA, but positive to RIA. The results indicated that adenovirus E3 early promoter could express the inserted foreign genes, and MIT worked well in the E3 region of Ad5 and could increase the expression capacity of the recombinants. The conditions for foreign gene expression and genetic stability of the recombinant viruses were studied in detail. There was no wild Ad5 discovered during the cotransfection experiments. The present study provides some experiences for studying adenovirus recombination.

Adenoviridae↗
PubMed1997

[Purification and application of viral capsid antigen of Epstein-Barr virus].

The viral capsid antigen of Epstein-Barr virus was purified from sf9 cells infected with recombinant Baculoviruses and the purified protein was used to establish ELISA and immuno-strip method for detection of VCA/IgG and VCA/IgA antibodies in human sera. A sensitive, specific and cost-effective method has been developed for serological mass survey.

Antibodies, Viral↗
PubMed1997

[Fluorescence studies on the mixed solid complexes of europium-terbium-1, 10-phenanthroline-phthalate systems].

The 1, 10-phenanthroline-phthalate complexes of europium and terbium have been synthesized. Two series of mixed complexes, mechanical ground complexes (series 1) and chemical synthesized with mixed EuCl3 and TbCl3 solutions (series 2), have been also prepared. Fluorescence studies on all of the samples were performed. The results of their fluorescence spectra excited by 365nm UV-light showed that there are interactions between europium ions and terbium ions in these two kinds of mixed complexes. Their fluorescence intensities strongly changed especially for chemical synthesized mixed complexes, in which the fluorescence intensities of europium ions were greatly sensitized by terbium ions and those of terbium ions were strongly quenched by europium ions. But the peak positions of their emission bands did not shift obviously. The structure of these complexes have been characterized by FT-IR spectra. The results suggested that no free COOH groups exist and all of the nitrogen atoms of 1, 10-phenanthroline molecules coordinate to rare earth ions in all of these complexes.

English Abstract↗
PubMed1997

[Fluorescence and FT-IR spectroscopic studies on the mixed solid complexes of europium and terbium phthalate].

In this investigation, the fluorescence and FT-IR spectroscopic studies on synthesized Eu-Tb phthalate complexes and mixed solid complexes of europium and terbium phthalates were perfomed. The experimental results of the emission spectra excited by 365nm UV-light showed that the emission peak positions of Eu ( III ) [or Tb ( III )] wer shifted slightly due to the interaction between Tb ( III )and Eu ( III ) ions. However, the fluorescence intensities of one rare eath ion Eu ( III ) [or Tb (III )] were strongly influenced by the other. FT-IR spectra indicated that the coordination structures of carboxyl groups, both in mechanically mixed and synthesized solid complexes, were also changed. These results suggested that there are interactions between Eu ( III ) and Tb ( III ) ions in their mixed complexes.

English Abstract↗
PubMed1997

The plasma concentrations of lidocaine after slow versus rapid administration of an initial dose of epidural anesthesia.

We measured venous blood concentrations of lidocaine in 15 patients undergoing lower abdominal or extremity surgery after epidural injection of lidocaine. Patients were divided into either an infusion group (Group I, n = 6) or a bolus injection group (Group II, n = 9). We administered 15 ml of 2% lidocaine into the epidural space at 1 mL/min in Group I and at 1 mL/3 in Group II. Venous blood was drawn at 3, 6, 9, 12, 15, 18, 21, 30, 60, and 90 min after injection for measurement of plasma lidocaine concentrations. The peak plasma concentration (Cmax) of lidocaine in Group I was significantly less than that in Group II (P < 0.0005). We conclude that slow epidural infusion can produce a lower Cmax of lidocaine compared with that of a bolus administration and thereby decrease the potential for systemic toxicity of the local anesthetic.

Anesthesia, Epidural↗
PubMed1997

[Some YAC contig construction and long range physical mapping at human X chromosome Xp11.3-21.3].

Human X chromosome short arm Xp11.3-p21.3 is an area, where several genetic disease gene loci are located. In this work, the YAC conting construction, long range physical mapping were done for this region. Some DNA probes and STS markers were used for YAC screening. Totally 77 YACs were obtained from the YAC libraries of CEPH, ICRF and ours. The size determination, 26 pairs of microsatelite STS analysis, single copy probe hybridization, Alu-PCR finger printing and long range physical mapping were conducted with these YACs. These results allowed us to map these YACs, and finally 6 YAC contigs were obtained in Xp11.3-21.3, covering about 15.3 Mb. This work will greatly facilitate the positional cloning of disease genes or the genome sequencing in this important region.

Chromosome Mapping↗