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G Wang

Publications and source records attributed to G Wang.

At least 703 records · Page 39Linked to original sources
PubMed1995

PCR amplification of animal DNA with human X-Y amelogenin primers used in gender determination.

The X-Y homologous-gene amelogenin has been described for use as a PCR sex typing test for humans. Previous studies have revealed that appropriate primers yield a 106 and 112 bp fragment from the human X and Y chromosome respectively. Our studies have found that a PCR product is also obtained from DNA isolated from a number of common animals. This animal PCR product is very close in size to that of the human female PCR derived product and may be confused as human under routine agarose gel electrophoresis. In this report we detail the variety of animals examined and a method that can maximize the usefulness of this system.

Amelogenin↗
PubMed1995

[Immunohistochemical study of epidermal growth factor in liver of mice infected with schistosoma japonicum].

In this immunohistochemical study we examined the expression and localization of the epidermal growth factor in liver of mice infected with schistosoma japonicum during regulatory phase of immunology and early phase of hepatic fibrosis. EGF immunostaining is localized along sinusoids and within cytoplasm of centrilobular area and around ova granuloma at 6,8 weeks of infection. Proliferation of Ito cells and collagen deposition in Disse space were found by electron microscope. The data led us to conclude that the ova depositing in liver could excite the release of EGF and cytokines, then promote proliferation of Ito cells and overgrowth of extracellular matrix (ECM) under the endothelium, resulting in hepatic fibrosis.

Animals↗
PubMed1995

[Primary non-Hodgkin's malignant lymphoma of bone in 5 patients].

The authors report here 5 cases of primary non-Hodgkin's malignant lymphoma of bone. All bones of the body can be involved, but the commonly inflicted ones are pelvis and femur. This kind of lymphoma possesses no special clinical features and X-ray manifestation, so it is very difficult to be diagnosed and easily misdiagnosed. The diagnosis can be made with the following 5 items: (1) local significance; (2) X-ray manifestation; (3) bone origination; (4) the no proof of originating from other tissues; and (5) pathological examination. This kind of lymphoma is mainly treated with radiotherapy, and adjuvant surgical treatment and chemotherapy are sometimes given.

Adult↗
PubMed1995

Biological effects of carbon ions with medium energy on plant seeds.

The biological effects of 46.6 MeV/u 12C6+ ions on four kinds of plant seeds were studied at the Heavy Ion Research Facility in Lanzhou (HIRFL), Institute of Modern Physics (IMP), Academia Sinica. The results show that germination of the seeds is inhibited by exposure to ions. In root tip cells of irradiated seeds, a great variety of chromosomal aberrations were observed. Sensitivities in terms of inhibition of germination and induction of chromosomal aberrations in the four species are correlated.

Carbon↗
PubMed1995

[Production and characterization of monoclonal antibody against aflatoxin B1].

Two hybridoma cell lines 1B5 and 2F1 capable of secreting specific monoclonal antibodies (McAbs) against aflatoxin B1 (AFT B1) were obtained. BALB/c mice were immunized by intrasplenic injection of AFT B1-human serum albumin conjugate (AFT B1-HSA) containing 9 AFT B1 residue per molecule. Spleen cells of BALB/c mouse with high serum antibody titer were fused with SP 2/0 myeloma cells in the presence of polyethylene glycol. Hybridoma cell lines were selected by using an indirect ELISA with AFT B1-keyhole limpet haemocyanin as coating antigen and grown as ascite tumour cells in BALB/c mice which previously had received an intraperitoneal injection with Freund's incomplete adjuvant. The McAbs were found to have strong reaction with AFT B1-bovine serum albumin conjugate (AFT B1-BSA) and no reaction with HSA or BSA. The reactivity of the McAbs with AFT analogs was determined by an indirect inhibition ELISA and the concentrations (ng/ml) required to inhibit 50 binding of McAb to AFT B1-BSA conjugate solid phase were AFT B1 4.0ng/ml, B2 36.9ng/ml, G1 23.3ng/ml and G2 403.3ng/ml for 1B5 McAb, and AFT B1 2.4ng/ml, B2 2.6ng/ml, G1 2.8ng/ml and G2 4.7ng/ml for 2F1 McAb.

Aflatoxin B1↗
PubMed1995

[Complications in multiple systems resulting from acute cerebrovascular diseases].

One hundred and eighty five patients died of acute cerebrovascular diseases with complications in multiple systems were studied. Statistical analyses showed that there were no organ and system failure (NOSF) in 47 cases, single organ and system failure (SOSF) in 47 and multiple organ and system failure (MOSF) in 91. Out of 90 (50%) cases who had cerebral herniation, 39 cases were complicated with SOSF and 53 cases with MOSF. Among the patients with acute brain diseases, 25% of them (46) died of SOSF (4%, 8 cases) and MOSF (21%, 38) without herniation. Incidence of failure of organ and system was higher with stomach, metabolism and lung than with heart, kidney and blood. It took on the average 24 and 12.5 hours for the first organ and system to fail and 4 days and 24 hours for the second organ in patients with intracranial hemorrhage and cerebral infarction. Occurrence of organ and system failure was closely related to sex, previous diseases and damage of brain stem, but not to the size and number of the lesion. It is suggested that cerebrogenic organ and system failure (COSF) or cerebrogenic multiple organ and system failure (CMOSF) be referred to functional failure of more than two organs or system not including brain itself as a result of acute brain diseases.

Brain Stem↗
PubMed1995

[Palatoplasty of speech disorders and acoustical characteristics].

Some cleft palate patients suffer from disorders of articulation despite early surgical repair of the cleft and improvement in velopharyngeal function. Some of these articulation disorders involve abnormal palatolingual contact. Fifty-one subjects were investigated acoustically as well as management ranged from 8 years to 36 years with a mean age of 20 years and 1 month. Their speech disorders were analyzed and classified into the follows: Chinese glottal stop, pharyngeal stop, pharyngeal fricative, nasality, palatal articulation and lateral articulation. There were more than two kinds of disorder speech in one case.

Adolescent↗
PubMed1995

[Familial exudative vitreoretinopathy].

Familial exudative vitreoretinopathy (FEVR) is an autosomal dominant inherited disease. The developmental abnormality of retinal vessels is the basis of various lesions in FEVR. 11 affected members (21 eyes) from 5 families with FEVR were studied. The emphasis was placed on describing the changes of fundus and fundus fluorescein angiography of the disease. Argon laser photocoagulation was performed on 8 patients (14 eyes) and they were followed for 5 approximately 14 months. The diagnosis, differential diagnosis, complications and treatment of FEVR were discussed with some materials in this paper.

Adolescent↗
PubMed1994

Comparison and frequency of ventricular arrhythmias after defibrillator implantation by thoracotomy versus nonthoracotomy approaches.

Postoperative exacerbation of ventricular arrhythmias has been reported in some patients treated with thoracotomy implantable cardioverter-defibrillators (ICDs). This phenomenon, which may be related to epicardial patch electrodes, may be less frequent after nonthoracotomy ICD implantation. In this nonrandomized study, postoperative arrhythmias in thoracotomy approaches (n = 52) were compared with those in nonthoracotomy approaches (n = 59). Preoperatively, all patients were clinically stable receiving an antiarrhythmic regimen chosen by serial drug testing. Nine of 52 patients in the thoracotomy group developed sustained ventricular tachycardia postoperatively while receiving the same antiarrhythmic regimen chosen preoperatively, and 1 patient eventually died. Two additional patients developed frequent and prolonged episodes of nonsustained ventricular tachycardia requiring changes in the antiarrhythmic regimen. In the nonthoracotomy group, only 3 of 59 patients developed sustained ventricular tachycardia and 1 developed frequent nonsustained ventricular tachycardia. Thus, only 4 of 59 patients in the nonthoracotomy group developed clinically significant ventricular arrhythmia during the postoperative period compared with 11 of 52 patients in the thoracotomy group (p < 0.05). Surgical mortality was 6% in the thoracotomy group, and 0% in the nonthoracotomy group. In the remaining clinically stable patients, a marked (sevenfold) increase in asymptomatic ventricular arrhythmias was noted in 15 of 39 patients in the thoracotomy group, and in 3 of 55 patients in the nonthoracotomy group (p < 0.05). Thus, postoperative exacerbation of ventricular arrhythmia, sometimes noted with thoracotomy approaches, is very rare with nonthoracotomy approaches.

Aged↗
PubMed1994

Characterization of cis-regulating elements and trans-activating factors of the rat cardiac troponin T gene.

To study the transcriptional regulation of the rat cardiac troponin T (cTnT) gene, chimeric genes composed of the upstream region (-757 to +193 base pairs (bp) relative to the transcription initiation site) of the cTnT gene and the bacterial chloramphenicol acetyltransferase (CAT) gene were constructed and transfected into primary cultures of neonatal cardiomyocytes and cardiac fibroblasts. Deletion analysis showed that a 41-bp fragment (-249 to -209 bp) containing the MEF-2-like motif is an essential element for minimal cardiac-specific expression of the rat cTnT gene. The proximal promoter (-208 to -1 bp) contains two consensus CArG boxes, one M-CAT motif, one AP2 site, and one TATA box. The construct (cTNT-208) composed of the CAT reporter gene driven by this proximal promoter did not show cardiac muscle-specific expression. Ligation of consensus MEF-2-like sequence into the upstream of this chimera only partially increased its ability to express in cardiomyocytes. These results suggest that the spacing among MEF-2-like motif and proximal promoter and/or the flanking sequences of the MEF-2-like motif are important in determining cardiac muscle-specific expression. By footprint analysis with a DNA fragment (-303 to +6 bp), we identified three novel regions (called A, B, and C) protected by protein extract from rat hearts, in addition to the known motifs such as MEF-2, M-CAT, and CArG. Gel retardation with the probe (-235 to -141 bp), containing the MEF-2-like motif, one of the CArG boxes, and the C region, or the 41-bp probe (-249 to -209 bp), containing the MEF-2-like motif, revealed different DNA-protein complexes formed by heart, skeletal muscle, and liver extracts. By using DNA affinity purification, DNA-binding proteins with apparent molecular masses of 22-26 kDa were identified from rat heart extract but not from skeletal and liver extracts, suggesting the involvement of cardiac-specific proteins in regulating the cTnT gene expression.

Animals↗
PubMed1994

Effects of funnel web spider toxin on Ca2+ currents in neurohypophysial terminals.

Funnel web spider toxin (FTX) is reportedly a specific blocker of P-type Ca2+ channels. The effects of FTX on the Ca2+ currents of isolated neurohypophysial nerve terminals of the rat were investigated using the 'whole-cell' patch-clamp technique. Both the transient and long-lasting Ca2+ current components were maximally elicited by depolarization from a holding potential equal to the normal terminal resting potential (-90 mV). Externally applied FTX inhibited the high-voltage-threshold, transient component of the Ca2+ current in a concentration-dependent manner, with a half-maximal inhibition at a dilution of approximately 1:10000. FTX also shifted the peak current of the I-V relationship by +10 mV. The long-lasting Ca2+ current component, which is sensitive to L-type Ca2+ channel blockers, was insensitive to FTX. The transient current, which is sensitive to omega-conotoxin GVIA, was completely blocked by FTX. These results suggest that there could be a novel, inactivating Ca2+ channel in the rat neurohypophysial terminals which is affected by both N-type and P-type Ca2+ channel blockers.

Alkaloids↗
PubMed1994

Beta/A4-evoked degeneration of differentiated SH-SY5Y human neuroblastoma cells.

beta/A4 peptides are known to induce neurodegeneration in cultures of rat brain cells and rat neural cell lines (Yankner et al: Science 250:279-282, 1990; Behl et al: Biochem Biophys Res Commun 186:944-950, 1992). The current data show that these peptides induce similar neurodegeneration in SH-SY5Y neuroblastoma cells, extending characterization of beta/A4 toxicity to a human nerve cell line. Human SH-SY5Y cells respond to aggregated beta/A4 with changes in cell shape, membrane blebbing, antigenic modification, loss of attachment to the substrate, and cell death. beta/A4 peptides require aggregation for maximum toxic effects, as cellular degeneration is evoked by aggregated beta/A4 1-42 and 4-41 cysteine but not by monomeric beta/A4 1-40. Aged (pre-aggregated) beta/A4 1-40 also evoked neurodegeneration. Antigenic changes comprise upregulation of Alzheimer's-type tau epitopes, recognized by the PHF-1 and Alz-50 monoclonals. These particular changes in tau support the connectivity between this in vitro model and mechanisms leading to neurodegeneration in Alzheimer's disease. A significant feature of the SH-SY5Y response is that cells must be differentiated before they become sensitive to the degeneration evoked by beta/A4. Signaling pathways leading to beta/A4-evoked neurodegeneration thus are under experimental control, becoming complete only when proliferating cells withdraw from the cell cycle and develop a postmitotic phenotype.

Alzheimer Disease↗
PubMed1994

Direct imaging of interactions between an icosahedral virus and conjugate F(ab) fragments by cryoelectron microscopy and X-ray crystallography.

The binding properties of seven mouse monoclonal antibodies (McAbs) raised against cowpea mosaic virus (CPMV) were characterized by conventional and inhibition enzyme-linked immunosorbent assay (ELISA) technique. McAb binding to CPMV on electron microscope (EM) grids was also assayed with gold-labeled anti-mouse antibodies. Two of the seven McAbs (5B2 and 10B7) were found to bind tighter to CPMV than the others in the inhibition ELISA and the EM assay. F(ab) fragments from both of these McAbs were prepared and complexed with CPMV in solution. Electron micrographs of flash frozen (vitrified) samples of native CPMV and CPMV complexed with F(ab) fragments from McAbs 5B2 and 10B7 as well as IgGs from 5B2 were recorded and reconstructions were computed at 23 A resolution for the CPMV/F(ab) complexes and 30 A resolution for the CPMV/IgG complex. Structures of all three complexes clearly displayed the F(ab) fragments distributed with icosahedral symmetry on the surface of CPMV. The IgG bound in a monodentate fashion with only one F(ab) attached to the virus surface. F(ab) fragments from 5B2 and 10B7 bound to nearly identical positions. The refined 2.8 A X-ray structure of CPMV was used to identify the roughly 30 amino acids covered by the F(ab) fragments. The "footprint" spans a subunit interface and appears spatially similar to antigenic site 3B on poliovirus. In a previous, preliminary report of the CPMV/F(ab) 5B2 complex (Wang et al., 1992, Nature 355, 275-278) the wrong enantiomorph of the reconstruction was chosen. This was corrected and, since the F(ab) binds close to a mirror plane, the change in the footprint was minor.

Animals↗