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R Wei

Publications and source records attributed to R Wei.

At least 37 records · Page 2Linked to original sources
PubMed1998

A novel method for DEAE-dextran mediated transfection of adherent primary cultured human macrophages.

Primary cultured human macrophages are difficult to transfect. We have developed a DEAE-dextran DNA transfection method that mediates the reproducible transfection of primary cultured adherent human macrophages. Three factors essential for successful transfection were identified: DEAE-dextran concentration, the quantity of DNA per transfection and the incubation time of the macrophages with the transfection medium. Maximum levels of luciferase expression were attained within 24 h and maintained for at least 56 h after transfection. While serum in the transfection medium attenuated transfection, the treatment of the macrophages with chloroquine, DMSO, or glycerol did not enhance transfection within this system. A CMV enhancer/promoter mediated substantially greater luciferase expression in the macrophages than either HIV or RSV LTRs. DEAE-dextran facilitated superior transfection compared to either cationic liposome and calcium phosphate methods, and was more practical compared to electroporation for multiple transfections. This transfection protocol provides a simple, inexpensive, reproducible method for the evaluation of gene expression in primary cultured adherent human macrophages.

Adult↗
PubMed1998

REMI mutagenesis and identification of pathogenic mutants in blast fungus (Magnaporthe grisea).

Blast fungus' mutant, which is very difficult to obtain, is the key substance in the study of the relation between pathogen and plant. Rice-Aichi-ashahi was used as the host and plasmid pBF101 or pCSN43 as foreign DNA fragment, and REMI mutagenesis was applied to tag the pathogenic sequence in rice blast fungus M.grisea. Three mutants (R2H65, R2H69 and R2B1565) related to pathogenicity were recovered from several hundreds of transformants. R2H69 and R2H65 produced merely strange conidia which could not form appressorium or yield abnormals, and pathogenicity test further confirmed that they were unable to cause disease. R2B1565 possesses the same phenotypes as those of the wild type except that the ability of causing disease was much reduced.

DNA Restriction Enzymes↗
PubMed1998

[A study on diagnosis of ocular adnexal lymphoid hyperplasia by polymerase chain reaction amplified IgH CDR-III sequence].

OBJECTIVE: To study the diagnosis and classification of ocular adnexal lymphoid hyperplasia and investigate its cell origin by using some molecular biological techniques. METHODS: 29 cases (31 eyes) of ocular adnexal lymphoid hyperplasia were examined for immunoglobulin heavy-chain (IgH) gene rearrangements by means of polymerase chain reaction (PCR) to amplify the complementarity determining region III (CDR-III) with formalin-fixed and paraffin-embedded tissue combining with histopathologic examination and immunophenotypic analysis. RESULTS: 17 eyes of malignant lymphoma and 5 eyes of reactive lymphoid hyperplasia demonstrated clear single band of the rearranged gene for the IgH chain between 100 bp. to 120 bp. The bilateral ocular adnexal lymphoma occurring simultaneously in 4 eyes (two individuals) exhibited identical band. 1 eye of malignant lymphoma, 8 eyes of atypical lymphoid hyperplasias and 6 eyes of reactive lymphoid hyperplasia showed no band or a smear band. CONCLUSIONS: The results show that this method can determine the clonality of the lymphoid hyperplasias. It may be as well in the examination of small monoclonal B cell populations for which immunophenotypical analysis is difficult. The method is an objective, accurate and useful approach for the diagnosis of ocular adnexal lymphoid hyperplasias.

Complementarity Determining Regions↗
PubMed1998

[The observation of proliferative cell nuclear antigen and AgNORs in ocular adnexal lymphoid hyperplasia].

PURPOSE: To investigate the expression of proliferative cell nuclear antigen and Nuclear Organizer Region in ocular adnexal lymphoid hyperplasia and its histopathologic classification. METHOD: Using anti-proliferative cell nuclear antigen monoclonal antibody (PC10) and AgNORs method, the proliferative cell in 34 cases of ocular adnexal lymphoid neoplasms (benign lymphoid lesion, BLL, 14 cases; atypical lymphoid hyperplasias, AH, 9 cases; malignant lymphomas, ML, 11 cases) were detected in formalin fixed and paraffin-embeded tissue. RESULTS: A significant difference between BLL and AH, BLL and ML was observed (PCNA P < 0.001, P < 0.001; AgNORs P < 0.01, P < 0.001); similar result was observed between AH and ML in PCNA index (P < 0.01). But there was not a significant difference in AgNORs count (P > 0.05). The linear regression coefficient between PCNA index and AgNORs number was excellent (0.8693). CONCLUSION: The two methods may be helpful to distinguish ocular adnexal lymphoid reactive hyperplasia and malignant lymphoma.

Antigens, Nuclear↗
PubMed1997

Alcohol dehydrogenase-catalyzed reduction of protein carbonyl derivatives.

A simple method for measuring protein carbonyl derivatives is described. The assay is based on the catalytic reduction of protein carbonyl derivatives by NADH-dependent alcohol dehydrogenase at pH 7.5. Bovine serum albumin, oxidized by a system that generates highly reactive hydroxyl radicals via a Fenton-type reaction, is reacted with NADH in the presence of the enzyme. The carbonyl derivatives are quantitated on the basis of absorbance changes at 340 nm using millimolar absorptivity of 6.2 mM-1 cm-1. The method correlates well with a method that utilizes 2,4-dinitrophenylhydrazine.

Alcohol Dehydrogenase↗
PubMed1997

Random amplified polymorphic DNA markers in crosses between inbred lines of Rhode Island red and White Leghorn chickens.

Reciprocal crosses and backcrosses were conducted between inbred Rhode Island Red and White Leghorn chickens differentiated for egg production and egg quality traits. Random amplified polymorphic DNA (RAPD) markers distinguishing inbred lines were detected. Twenty-two polymorphic bands were found from screening 120 single 10-mer random primers of which two were consistent with sex-linked markers. Of 90 pairwise two-point linkage analyses completed for the autosomal markers, four close linkages (8.2 cM to 14.9 cM) were significantly different from zero.

Animals↗
PubMed1997

[Automated perimetry analysis of optic nerve compression caused by orbital tumors and tumor-like lesions].

OBJECTIVE: In order to evaluate the relationship between the orbital neoplasms and the resulting visual field damage. METHOD: 22 cases of orbital tumors and tumor-like lesions were examined with automated perimetry. RESULTS: Visual field alterations varied from arcuate, inferior altitudinal, ceeocentral scotomas, to temporal hemianopsia and diffuse defect. The surgical removal of the tumor or steroid administration was followed by partial or full perimetric recovery. CONCLUSIONS: Visual field alteration reflects the severity of the optic nerve damage. The impairment is reversible. Apical masses may cause severe optic neuropathy. Axonal and vascular factors are involved in the main pathological mechanisms of the disease.

Adult↗
PubMed1996

Conditioned medium from activated microglia promotes cholinergic differentiation in the basal forebrain in vitro.

In earlier studies we found that treatment with interferon-gamma (IFN-gamma) produced an 8- to 11-fold increase in choline acetyltransferase (ChAT) in cultured cells taken from Embryonic Day 16 (E16) septal nuclei with adjacent basal forebrain (SN/BF). Since younger cultures responded even more profoundly to IFN treatment, we have tested the possibility that the action of IFN (or its intermediate; see below) is to prompt the cholinergic differentiation of neuronal precursors. SN/BF cultures of various ages were labeled with a retrovirus engineered to express beta-galactosidase (Lac-Z), and ChAT-positive descendants of the retrovirally labeled precursors were counted. IFN-gamma treatment of cultures caused as much as an 8.8-fold increase in the proportion of ChAT-positive cells present in Lac-Z-positive clones, suggesting that IFN promoted cholinergic differentiation in precursor populations. By contrast, bFGF increased clone size but did not change the proportion of ChAT-positive cells. NGF affected neither. Only ameboid microglia present in the cultures responded to IFN with characteristic nuclear translocation of the signal transducing molecule p91, suggesting that a microglial-derived molecule may mediate the action of IFN. Consistent with this hypothesis, conditioned media from cultures of enriched, activated microglia also increased ChAT activity in a dose-dependent fashion. Conditioned media from an unstimulated macrophage/monocyte cell line (RAW 264.7) also proved extremely efficacious in raising ChAT activity. In addition, conditioned media from both activated microglia and RAW 264.7 cells increased the proportion of ChAT-positive cells in retrovirally labeled clones to the same extent as IFN itself, suggesting the possibility that they contain the molecule(s) that mediates the action of IFN. Preliminary characterization of this molecule suggests that it is a very stable and large protein. Together these data suggest that a molecule promoting cholinergic differentiation is produced by activated microglia and other macrophage-like cells. The identity of this molecule and its precise role in normal development await its further purification.

Animals↗
PubMed1994

Interferon-gamma promotes cholinergic differentiation of embryonic septal nuclei and adjacent basal forebrain.

In cultured rat embryonic septal nuclei with adjacent basal forebrain, murine interferon-gamma (IFN gamma) produces a striking increase in choline acetyltransferase (ChAT) activity and mRNA. The effect of IFN gamma on cholinergic differentiation is more potent in E14 cultures than in older cultures. IFN gamma does not cause a change in the affinity of ChAT for choline, nor does it affect cell proliferation. Whereas IFN gamma doubles neuronal cell number, the cholinergic cell number increases more than 7-fold. Ameboid microglia respond to IFN gamma with the translocation of p91 to the nucleus. The action of IFN gamma is not mediated by NGF or bFGF. The enhancement of cholinergic expression that occurs with increased cell density may be partly attributable to an endogenous IFN gamma-like molecule, since antibodies to IFN gamma offset the effects of increased cell density.

Animals↗
PubMed1994

Fatal pulmonary embolism in spinal cord injury.

Fatal pulmonary embolism (PE) is a major cause of mortality in patients with spinal cord injury. In order to ascertain those characteristics that might predict this event, we reviewed the records of all patients with autopsy-proven massive PE admitted to a regional spinal cord care center over a 5-year period. The information analyzed included patient age, sex, race, height, weight, type of accident, prior use of tobacco, alcohol, or narcotic drugs, level of injury, presence of spasticity, surgical procedures, infections, transfusions, and type of anticoagulant prophylaxis. Forty-two concurrently hospitalized patients with spinal cord injury served as control subjects. Significant differences between cases and control subjects were observed for level of injury (fewer thoracic and lumbar injuries in cases, p = 0.04), less spasticity in cases (p = 0.01), and greater body mass index in cases (p = 0.01). There was also a trend toward more advanced age in the cases (p = 0.1) and more frequent serious infections (p = 0.08). Lastly, low molecular weight heparin had been used as thromboprophylaxis in a greater proportion of control subjects than cases (60 percent vs 22 percent, p = 0.07), suggesting that low molecular weight heparin may be more effective in preventing fatal PE than unfractionated heparin.

Adult↗
PubMed1994

Reinfection with Schistosoma japonicum after treatment with praziquantel in Poyang lake region, China.

The study on reinfection with Schistosoma japonicum after treatment was carried out in a cohort of subjects in a heavy endemic village of Poyang lake region, China. After mass treatment with praziquantel in non-transmission time, detailed observations of water contact were estimated using the mean area of skin exposed daily. One year after treatment, the prevalence of infection in study subjects was 54.48%, returning to 83% of initial prevalence. The peak prevalence occurred the 11-15 year age class, but intensity of exposure also varies with age and that age group supporting the higher prevalence of reinfection had high levels of exposure. Among groups of subjects with a similar exposure stratum, young subjects under the age of 21 years were more heavily reinfected, while no heavy reinfection was observed in adults (> or = 25 years). These observations suggest that subjects in this area slowly acquire an increasing degree of immunity to lighten the intensity of infection with S. japonicum.

Adolescent↗
PubMed1992

A synthetic early promoter from a baculovirus: roles of the TATA box and conserved start site CAGT sequence in basal levels of transcription.

Many baculovirus early genes and insect genes transcribed by RNA polymerase II have a conserved transcription start site sequence (CAGT) located downstream of a consensus TATA box. To examine the functions and interactions of these two motifs in initiating accurately positioned basal transcription, a 43-nt synthetic promoter was synthesized from the TATA box and start site sequences of the gp64 early promoter from the Orgyia pseudotsugata multicapsid nuclear polyhedrosis virus (OpMNPV). The synthetic promoter initiated accurately and was also transactivated by the baculovirus transcriptional activator, IE1. To determine the roles of sequences within the 43-nt synthetic promoter, a series of linker-scanning and spacing mutations were analyzed for transcriptional activity, start site selection, and transactivation. Linker-scanning mutations were examined in vivo by transient expression and reporter gene assays. To examine transcription start site selection, promoter constructs were used for in vitro transcription in nuclear extracts from uninfected Spodoptera frugiperda (Sf9) cells. In vivo and in vitro analyses show that the TATA box, and not the start site CAGT, is the primary element controlling start site selection. Substitution of the conserved start site CAGT sequence resulted in a reduction of both reporter gene activity and in vitro transcripts, although transcripts initiated accurately. Data from linker-scanning and spacing mutations indicate that the conserved start site CAGT sequences are not required for accurate initiation but sequences at the start site play an important role in initiation efficiency.

Baculoviridae↗
PubMed1992

Inheritance of tinted eggshell colors in white-shell stocks.

The present study was conducted to study the genetics of tinted eggshell colors in two breeds of chickens laying white-shell eggs. Reciprocal crosses were made between an inbred White Leghorn line (ES) and an inbred Ancona line (ANC). The F1 birds were intercrossed and F1 females were backcrossed to each of the original lines. Eggshell color from each resultant group was measured using a Minolta chromometer, and a value (e) representing the color intensity adjusted by hue and saturation was used as the measurement criterion. Age, hatch group, and crosses each contributed significantly to the variation seen in eggshell color. Distribution comparisons indicated that two major autosomal loci affected the trait in these lines: one gene having incomplete dominance controls the amount of pigment deposition; the second completely inhibits pigment deposition when homozygous recessive. A test of goodness of fit supported this hypothesis. Genetic components were estimated by linear models. Epistasis, dominance, and additive effects contributed significantly to this trait. No sex-linked effects were noted.

Analysis of Variance↗
PubMed1992

[Effect of radix Astragali and radix ginseng in enhancing the metabolism of human myocardial cells in vitro].

Our experiment indicated that in Radix Astragali and Radix Ginseng treated human myocardial cell cultures the level of LDH and SDH elevated in varying degrees and in Radix Ginseng treated cells the cAMP showed higher levels but in Radix Ginseng treated ones the same was not observed. This suggests that the metabolism of myocardial cells is enhanced by Radix Astragali or Radix Ginseng.

Cells, Cultured↗
PubMed1991

Theoretical analysis of H-Horn annular phased array system for heating deep-seated tumors.

This paper discusses a type of annular phased array system--H-Horn APA. The phase and amplitude control of power deposition patterns for this system are theoretically analyzed at a frequency of 200 MHz. The formulas for calculating E-field and SAR for this APA system are derived, and can be applied to other type APA systems. Models of computerized tomography (CT) scans from liver and lung regions have been used, respectively, for predicting optimization of E-field and SAR patterns in the case of the relative phase and amplitude changes. It is shown that the techniques of the phase and amplitude control of SAR patterns result in more selectively and effectively heating of tumors situated eccentrically and deeply within bodies of patients. The APA hyperthermia described in this paper shows great promise, and it looks very useful for developing clinical applications.

Humans↗
PubMed1988

Reduction of iodonitrotetrazolium violet by superoxide radicals.

p-Iodonitrotetrazolium (2-(4-iodophenyl-3-(4-nitrophenyl)- 5-phenyltetrazolium; INT) was reduced to a water-soluble product with an absorbance maxima at about 505 nm (reddish pink) by superoxide anion (O2-.) generated by xanthine/xanthine oxidase. The rate of INT reduction was linearly related to the xanthine oxidase activities, and was inhibited by superoxide dismutase. The soluble product may further be converted to an insoluble product, presumably nonionic formazan, with an absorbance maxima of 490 nm (purplish), under certain conditions, and the rate of the formazan formation depended on pH and protein concentration.

Free Radicals↗
PubMed1988

Maternal and neonatal urinary excretion of sulfate and glucuronide ritodrine conjugates.

Ritodrine is a beta 2-adrenergic agonist that is used clinically for the management of preterm labor. The beta 2 activity of ritodrine produces the relaxation of smooth muscles and is believed to act directly on the beta 2-receptors of the myometrium. Reports in the literature suggest that ritodrine is inactivated by sulfate and glucuronide conjugation, but this has not been verified in humans. Studies on animal models indicate that the sulfate conjugate is a major urinary metabolite of ritodrine. Recent investigations of maternal and neonatal urinary excretion of ritodrine indicate that 80% to 90% of the drug is in the form of conjugates. The purpose of this study was to determine the nature of these conjugates. Our study indicates that both the mother and neonate excrete glucuronide and sulfate conjugates of ritodrine. The sulfate conjugate accounts for 45% of maternal excretion and 66% of neonatal excretion; the glucuronide conjugate accounts for 38% and 23% of maternal and neonatal excretion, respectively. Significantly different metabolic profiles suggest that the neonate may be capable of forming conjugated metabolites of ritodrine.

Arylsulfatases↗