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Biomedical subjects

Z Hu

Publications and source records attributed to Z Hu.

At least 343 records · Page 19Linked to original sources
PubMed1993

Diagnosis of active Paragonimus westermani infections with a monoclonal antibody-based antigen detection assay.

We evaluated the performance of Dot-enzyme-linked immunosorbent assays designed to detect species- and stage-specific antigens of Paragonimus westermani in sera with monoclonal antibodies as serodiagnostic tests for active paragonimiasis. Sera from all donors with parasitologically confirmed infections with P. westermani contained adult worm antigens, as did a high proportion of sera from persons suspected to be infected with this parasite. A smaller proportion of these sera also contained metacercarial stage-specific antigens. Sera from donors with other helminth infections, with confirmed pulmonary tuberculosis, or from healthy Chinese donors were nonreactive in the assay. Treatment of experimentally infected animals with praziquantel triggered a marked but transient increase in serum levels of adult P. westermani antigens, which then gradually disappeared within the next two months. The results of our studies indicate that the antigen-detection assay we have developed is a highly specific and sensitive diagnostic test for active infections with P. westermani.

Acute Disease↗
PubMed1993

Activation of hepatic stem cell compartment in the rat: role of transforming growth factor alpha, hepatocyte growth factor, and acidic fibroblast growth factor in early proliferation.

We have demonstrated previously a pronounced increase in the expression of hepatocyte growth factor (HGF) (Z. Hu, R. P. Evarts, K. Fujio, E. R. Marsden, and S. S. Thorgeirsson, Am. J. Pathol., 142: 1823-1830, 1993), transforming growth factor alpha (TGF-alpha) (R. P. Evarts, H. Nakatsukasa, E. R. Marsden, Z. Hu, and S. S. Thorgeirsson, Mol. Carcinog., 5: 25-31, 1992), and acidic fibroblast growth factor (aFGF) (E. R. Marsden, Z. Hu, K. Fujio, H. Nakatsukasa, S. S. Thorgeirsson, and R. P. Evarts, Lab. Invest., 67: 427-433, 1992) that coincided with the proliferation and differentiation of putative hepatic stem cells and perisinusoidal stellate (Ito) cells. Here, we examine the earliest stages of stem cell activation in rat liver using an experimental model involving treatment with acetylaminofluorene and partial hepatectomy (R. P. Evarts, P. Nagy, E. Marsden, and S. S. Thorgeirsson, Carcinogenesis (Lond.), 8: 1737-1740, 1987). Histochemical identification of stem cell progeny and Ito cells was accomplished by OV6 and desmin antibodies, respectively. Expression of the 2.1-kilobase alpha-fetoprotein transcripts and the concomitant DNA synthesis ([3H]thymidine label) were used as indicators for the activation of the stem cell compartment. Expression of HGF, TGF-alpha, and aFGF was analyzed at the time of partial hepatectomy and 4, 12, 24, 48, 72, and 92 h after the operation. [3H]-Thymidine-labeled OV6- and desmin-positive cells were present in the portal space and in the Glisson capsule 4 h after partial hepatectomy.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

[Fundus fluorescein angiographic findings of sympathetic ophthalmia].

Eight cases of sympathetic ophthalmia diagnosed by histopathologic examinations of the enucleated exciting eyes were collected and the fundus fluorescein angiographic (FFA) findings of the sympathized eyes in acute stages were analyzed. The manifestations of the FFA were divided into three types. We suggest that if one eye has a history of trauma and the other eye loses visual acuity rapidly accompanied with uveitis signs after certain incubation period, the fundus fluorescein angiography should be examined to achieve a clinically objective diagnostic basis so that the patients are treated in time.

Adult↗
PubMed1993

Study on application of the silicone oil in the reattachment of complicated retinal detachment.

Sixty eyes with complicated retinal detachment were treated by vitrectomy combined with silicone oil tamponade (27 eyes of PVR grade D, 15 eyes of giant retinal tears with posterior flat folded-over, 13 eyes of posterior or macular hole, 5 eyes of traumatic PVR). After 3-24 months follow-up, the study showed retinal anatomic reattachment in 48 eyes in which the visual acuity of 32 eyes was 0.05 or better. The authors consider that vitrectomy and peeling make the silicone oil tamponade perfect the vitreous surgery and improve the successful rate. The theory of silicone oil tamponade, the indications, advantages and disadvantages of silicone oil tamponade are discussed in this paper.

Adolescent↗
PubMed1993

Expression of hepatocyte growth factor and c-met genes during hepatic differentiation and liver development in the rat.

Hepatocyte growth factor (HGF) is a potent mitogen for mature hepatocytes in vitro. The receptor for HGF has recently been characterized as the product of the proto-oncogene c-met. We have examined the possible involvement of HGF in hepatic growth and differentiation in the rat. The experimental systems used were acetylaminofluorene treatment combined with partial hepatectomy to induce proliferation and differentiation of oval cells in adult liver and the pre- and postnatal liver. In the acetylaminofluorene model, Northern blot analysis showed that level of HGF transcripts increased one day after partial hepatectomy, reached a peak by day 6, were maintained at that level until day 13, and then declined, reaching normal level at 20 days. The expression of c-met also increased gradually, reached a peak around 9 to 13 days after partial hepatectomy, at which time oval cell proliferation was most prominent. In the developing liver, an elevated level of HGF transcripts was found between 4 and 21 days after birth. The expression of c-met also slightly increased at the same time. In situ hybridization showed that the transcripts for HGF were localized in desmin-positive Ito cells, whereas the transcripts for c-met were strongly expressed by oval cells. We have shown earlier that Ito cells and oval cells proliferate simultaneously and exist in close proximity in the acetylaminofluorene model and that Ito cells are a primary source of growth factors such as transforming growth factor-alpha and acidic fibroblast growth factors. The data presented here suggest that HGF is, in combination with other growth factors, involved in the proliferation and differentiation of oval cells via a paracrine mechanism.

2-Acetylaminofluorene↗
PubMed1992

Genomic typing of hepatitis C viruses present in China.

Hepatitis C virus (HCV) genomic clones were obtained from the serum of Chinese HCV carriers using a polymerase chain reaction-based approach. Consensus sequences were derived from (1) the structural region (nt 1-1543) for one carrier, (2) the hypervariable region V (nt 1156-1233) from four carriers and (3) region V3 from four carriers. Region V3, located in the nonstructural domain NS5 (nt 7066-7137), has been previously shown to be a particularly good marker for the genomic typing of HCV isolates [Inchauspe et al., Proc. Natl. Acad. Sci. USA 88 (1991) 10292-10296]. Comparison of these sequences with sequences from geographically distinct HCV isolates indicates that Chinese HCV strains are closely related to, though distinguishable from, Japanese prototype strains. One amino acid motif, GGAA, located in region V, was found to be conserved only among Chinese isolates. This may define a new subgroup among HCV isolates.

Alanine Transaminase↗
PubMed1992

Expression of transforming growth factor-alpha in regenerating liver and during hepatic differentiation.

Both the level of expression and cellular distribution of transcripts for transforming growth factor-alpha (TGF-alpha) were studied in adult rat liver after partial hepatectomy and during hepatic differentiation in fetal, neonatal, and adult livers by northern blot analysis and in situ hybridization. A marked increase in the expression of TGF-alpha was observed in neonatal livers and in adult livers after partial hepatectomy and during hepatic regeneration following modification of the Solt-Farber protocol. Quantitation of silver grains after in situ hybridization with a TGF-alpha riboprobe revealed a sixfold to eightfold increase in fetal and neonatal hepatocytes. Moreover, the expression of TGF-alpha in the liver 3 wk after birth was still fourfold higher than that of the adult quiescent liver. Both proliferating oval cells and basophilic foci of hepatocytes generated by modification of the Solt-Farber protocol were positive for TGF-alpha transcripts. The level of TGF-alpha transcripts was sixfold higher in the basophilic foci than in the surrounding liver. High concentrations of TGF-alpha transcripts were observed in the oval cells that lined pseudoducts and in the transitional cells proliferating within the ducts. The combination of in situ hybridization and immunocytochemistry using cell-specific antibodies revealed the presence of TGF-alpha transcripts in both oval cells and in perisinusoidal stellate cells. The observation that TGF-alpha transcripts were found both in primitive liver epithelial cells and perisinusoidal stellate cells suggests that this growth factor, in addition to its mitogenic action, may also have other important functions in the liver.

Animals↗
PubMed1992

Prolonged activation of alpha 1 adrenoceptors induces down-regulation of protein kinase C in vascular smooth muscle.

Sustained exposure of vascular smooth muscle to catecholamines results in desensitization of alpha 1-adrenoreceptor-mediated vascular smooth muscle contraction. The present study was designed to determine the effects of prolonged exposure of blood vessels to catecholamines on protein kinase C (PKC) activity. Incubation of rat aortic smooth muscle with 10 microM norepinephrine (NE) for 4 h resulted in a threefold decrease in sensitivity of the contractile response of rat aortic smooth muscle to the phorbol ester 4 beta-phorbol 12,13-dibutyrate (PDBu); this loss in sensitivity was dependent on the presence of endothelium. NE induced a 45% decrease in enzymatic activity of the soluble and particulate forms of PKC. With [3H]PDBu used to label phorbol ester receptor binding sites in the aorta, there was a 34% decrease in [3H]PDBu binding sites in NE-treated blood vessels without change in binding affinity for the ligand. To determine whether this loss in enzymatic activity and [3H]PDBu binding resulted from a decrease in the quantity of the enzyme, Western blot analyses were performed using a monoclonal antibody (MoAb) against PKC. This approach confirmed the presence of an 80-Kd immunoreactive PKC in the soluble fraction of rat aortic smooth muscle and demonstrated a 44% decrease in the amount of PKC in blood vessels after sustained exposure to catecholamines. Our results demonstrate that prolonged activation of alpha-adrenoceptors in blood vessels leads to down-regulation of PKC which may contribute to desensitization of contraction mediated by vasoconstrictors.

Animals↗
PubMed1992

Expression of acidic fibroblast growth factor in regenerating liver and during hepatic differentiation.

BACKGROUND: Acidic fibroblast growth factor belongs to a family of growth factors that show a high affinity for heparin sulfate proteoglycans. In vitro, it participates in various cellular functions including proliferation, differentiation, angiogenesis, and cell migration, but in vivo, the physiologic role of this growth factor is still not clearly defined. EXPERIMENTAL DESIGN: The level of expression and also cellular distribution of transcripts for acidic fibroblast growth factor (aFGF) were studied in adult rat liver after partial hepatectomy and during hepatic differentiation in fetal, neonatal, and adult livers by Northern analysis and in situ hybridization techniques. RESULTS: After partial hepatectomy a significant increase in the transcripts for aFGF was observed at 24 hours, whereas at 4 and 12 hours after the operation, the level of transcripts were similar to those of sham-operated animals. In the postnatal liver a high level of aFGF expression was present when the most evident transition from 2 to 3 cell thick hepatic cords to normal hepatic structure is taking place (Ogawa K, Medine A, Farber E. Br J Cancer 1979;40: 782-90). In contrast during the prenatal period, when the liver is still a hemopoietic organ and only a small number of sinusoids are present, low level of aFGF transcripts could be found. Animals treated with 2-acetylaminofluorene and partial hepatectomy (Evarts RP, Nagy P, Marsden E, Thorgeirsson SS. Carcinogenesis 1987;8:1737-40) displayed a marked increase in hepatic aFGF transcripts at the peak of proliferation of primitive liver epithelial cells (oval cells) and perisinusoidal stellate cells (Ito cells) in addition to hepatocytes. In situ hybridization combined with immunocytochemistry using oval and Ito cell specific antibodies revealed the presence of transcripts both in oval cells and Ito cells. Basophilic areas composed of small hepatocytes had a 3-fold increase in the level of transcripts as compared with the surrounding hepatocytes. CONCLUSIONS: These experiments demonstrate that the expression of aFGF is highest during the late stages of hepatic morphogenesis in newborn animals as well as during hepatic differentiation in adult liver.

Animals↗
PubMed1992

[Survey of suicidal mortality rate in several districts of Sichuan province].

A survey of the suicidal mortality rates in two cities and six districts in Sichuan province was carried out from 1980 to 1988 by the authors. The average suicidal mortality rate (ASMR) in these districts from 1980 to 1988 was 15.5/10(5), and the population and suicidal mortality rate positively correlated, r = 0.53. The ASMR in the male was 14.9/10(5), in the female 17.1/10(5), in the urban area 9.4/10(5), in the rural area 21/10(5), and the ASMR in the urban area was higher than that in the rural area (P < 0.05). The peak age of suicidal mortality was around twenty years.

Adolescent↗
PubMed1992

In vitro and in vivo biotransformation and covalent binding of benzo(a)pyrene in Gunn and RHA rats with a genetic deficiency in bilirubin uridine diphosphate-glucuronosyltransferase.

Like many polycyclic aromatic hydrocarbons in the environment, >30% of benzo(a)pyrene (BP), an environmental carcinogen and teratogen, is eliminated by glucuronidation, which competes with a toxifying pathway involving cytochrome P-450-catalyzed bioactivation of BP to a carcinogenic reactive intermediate, BP-7,8-diol-9,10-oxide. Genetic deficiencies in bilirubin UDP-glucuronosyltransferase (GT) occur in >5% of the population (Gilbert's disease, Crigler-Najjar syndromes), and this could predispose such people to the toxic effects of polycyclic aromatic hydrocarbons and other environmental chemicals that are eliminated substantially by glucuronidation. This hypothesis was evaluated in vitro and in vivo in homozygous Gunn and RHA rats, both of which are genetically deficient in GT. [7,10-14C]BP was incubated with rat liver microsomes, NADPH and uridine diphosphate-glucuronic acid. BP and its metabolites, including its glucuronide conjugates, were measured by high performance liquid chromatography with a radioisotope detector, and the covalent binding of BP to microsomal protein was measured by liquid scintillation counting. Compared with Wistar (Gunn) controls and RHA homozygous normal controls, microsomes from homozygous GT-deficient Gunn and RHA rats demonstrated 18.5 to 48.5% lower production of the glucuronide conjugate, with 2 to 3-fold greater covalent binding of BP (P < .05). Elevated BP covalent binding correlated with reduced glucuronidation in both Gunn (r = -0.705, P = .003) and RHA rats (r = 0.824, P = .001). In vivo, the covalent binding of [G-3H]BP to hepatic DNA and microsomal protein was enhanced 2-fold and 1.5-fold, respectively, in homozygous RHA GT-deficient rats, compared with RHA GT-normal controls (P < .05)(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

[A preliminary study on growing tempo of Ophisourus harti Boulenger].

Under experimental circumstances, the relationship between the growing tempo of Ophisourus harti and its age, fodder, outside temperature and humidity has surveyed. Suggestions have accordingly been made with regard to the rational utilization and protection of the resources.

Animal Feed↗
PubMed1992

[Effect of Cordyceps sinesis on T-lymphocyte subsets in chronic renal failure].

Synchronous measurements of renal function and T-cell subsets were taken in 51 cases of chronic renal failure (CRF) patients. Cordyceps sinesis 3-5 g/d was given to 28 out of these 51 patients, which was considered as follow-up group. The results were stated as follows: (1) Obvious decrease of OKT3, OKT4, OKT4/OKT8 was found in CRF (P < 0.01). (2) OKT4 and OKT4/OKT8 were proportional to plasma albumin and Hb levels (P < 0.05). (3) After administration of Cordyceps sinesis, improvement of renal function and OKT4, OKT4/OKT8 were confirmed. This study indicated that cellular immune function was decreased in CRF. Administration of Cordyceps sinesis might improve their renal function and as the same time enhance the cellular immune function in CRF.

Adult↗
PubMed1991

[Status quo and prospects of oral liquid prepared from Chinese drugs].

This paper reviews the rise of oral liquids and their preparations, control standards, pharmacological research and clinical pharmacy, etc. On the basis of investigation, an overall discussion is given in respect to product variety and sale, pharmaceutical research and development, and social benefit from new products, so as to highlight the merits of Chinese medicinal materials.

Administration, Oral↗
PubMed1991

[Bullous retinal detachment and its classification of fluorescence angiography].

Nineteen cases with (27 eyes) of bullous retinal detachment, male (24 eyes), female (3 eyes), were reported. The age of onset was from 16 to 46, mean 36.7. All of them underwent fundus fluorescence angiography (FFA). According to the results of FFA, it could be divided into two types of fluorescence angiograph changes were seen: type I, multiple pigmental epithelial damage at posterior pole, it consisted of twelve cases (16 eyes); type II, extensive pigmental epithelial damage at posterior pole, it consisted of seven cases (11 eyes). The treatments consist: medicine; medicine and photocoagulation; combined medicine, transscleral drainage and photocoagulation. Among 27 eyes, 20 had their vision improved after treatment, 4 eyes unchanged and 3 eyes decreased in vision. 22 eyes obtained their retinal reattachment (81.4%). The diagnosis, differential diagnosis, classification and treatment are discussed.

Adolescent↗