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Biomedical subjects

X Zhu

Publications and source records attributed to X Zhu.

At least 649 records · Page 36Linked to original sources
PubMed1995

[Clinical analysis of 102 patients with congenital inner ear malformation].

Hearing loss and CT findings of 200 ears from 102 cases with congenital malformation of inner ear were included in our study. Hearing loss was typically bilateral severe, or total deafness. 75 percent of them were found deaf within one-year-old. In addition, 47 patients' (46%) mothers were noted to have caught a cold in first trimester of pregnancy. Temporal bone abnormalties were described as five types: 1. Michel malformation, 2. Mondini malformation, 3. enlargement of the vestibular aqueducts, 4. developmental deformity of cochlear aqueduct, 5. developmental deformity of internal acoustic meatus. Most cases showed malformations of vestibule or vestibular aqueducts.

Child↗
PubMed1995

[The treatment of gastric carcinoma in III stage].

From 1975 to 1989, we treated 238 cases of gastric carcinoma in III stage, 90.7% of these were followed up. The total 5-year survival rate was 45.4%, 10-year survival 33.7%. The 5-year survival rate and 10-year survival rate (56.3% and 47.5%) in the extensive radical treatment group (102 cases, selective R3 or R3) was much higher than that of routine radical treatment group (114 cases R2). The 5-year survival rate and 10-year survival rate in the group with auxillary post-operational chemotherapy were much higher than those of the group without chemotherapy. The post-operative survival rate in the group with chemotherapy plus Chinese medicine was much higher than that of the group with chemotherapy alone. The peritoneal metastatic rate of the group with peritoneal flushing plus chemotherapy (18.7% and 20.6%) was much longer than that of the group without peritoneal flushing and/or chemotherapy (31.9%). We consider that the best treatment of gastric carcinoma in III stage is the sufficient removal of gastric lymph nodes for the prevention of metastasis through peritoneal and circulatory route.

Adult↗
PubMed1995

[The trend of the gallstone disease in China over the past decade].

The present study is the second national survey on 3911 srugically treated cases of gallstones which was collected from 33 hospitals of 5 provinces and 2 main cities of China and aims at reevaluating and comparing the trend of the gallstone disease in China since the first national survey was completed 10 years ago. The results showed that cholelithiasis remained one of the commonest surgical diseases and accounted for 11.5% of overall hospitalized patients during the same period of time and it occurred mostly in females of over 50 years of age, with a female-male ratio of 2.57 Vs 1.80% of the patients with single positioned gallstones had their stones in gallbladder and was mainly cholesterol stone in nature while pigmented bile duct stones was found only in 10% of the patients, which made the gallbladder Vs bile duct stone ratio and the cholesterol Vs pigment stone ratio a significant difference as 7.36 : 1 and 3.4 : 1 respectively when compared with the results of 1.5 : 1 and 3.4 : 1 from the first national survey, 10 years ago. A significantly decreased incidence of biliary ascariasis and biliary bacterial infection rate as well as the dietary changes from low protein, fat high vegetable to the opposite were directly relevant to the above alterations on the location and the type of the gallstones.

Adolescent↗
PubMed1995

[An observation on nucleating activity of monoconjugated bilirubin (MCB) in model bile system].

Recently, the increasing data suggest that the pathogenesis of cholesterol gallstones may be related to the imbalance between pro- and anti-mucleating factors in bile. Our previous results have shown that monoconjugated bilirubin (MCB) possessed certain pro-nucleating activity and might play an important role in the formation of gallstones. The present study was made to observe the effect of MCB on nucleating activity by using our previous established methods of purification and preparation of MCB in model system of supersaturated bile according to Kibe's method with cholesterol saturation index of 1.2, total lipid concentration of 10g/dl, and bile salt phospholipid ratio of 2.3. Nucleation time (NT) was observed in 3 experimental groups with six samples each and 2 different contents of lyophilized MCB was added to above model bile rendered a final MCB concentration of (1) 173 microM; (MCB 1 group) (2) 340 microM; (MCB-2 group) and (3) no MCB in the as control group. The results were NT 3.33 +/- 0.52, 2.17 +/- 0.41 and 5.83 +/- 0.75 days in groups. 1, 2 and 3 respectively with the P value < 0.05 when compared between the 2 groups. The nucleating activity (NA) value was 0.5712 and 0.3722 in groups 1 and 2, which revealed that the NA elevated in parallele with the dose of MCB added in model bile. Our findings suggust that MCB has a strong pro-nucleating activity in model supersaturated biles, and MCB may participate in the formation of cholesterol gallstones throngh its special pro-nucleating activity.

Bile↗
PubMed1995

[Clinical application of expanded thin skin flap].

Fifteen patients were treated with the expanded thin skin flaps with the large area defects of soft tissue resulting from scar, pigmented nevus, hemangioma, chronic ulcer and neurofibroma. The operative procedure includes tissue expansion and defatted flap transplantation. All flaps that preserved only a thickness of 3 mm adipose tissue or superficial fascia beneath the subdermal vascular network survived with the primary healing of 12 cases and the delay healing of 3 cases in the maximal ratio of length to width 4.3:1. The details of clinical experience and primary experiment were presented.

Adolescent↗
PubMed1995

[Expression of insulin-like growth factor-I gene in normal and diabetic rat eye].

The expression of insulin-like growth factor I (IGF-I) gene was studied in both normal and diabetic rat eyes via in situ hybridization. The results revealed the regional expression of IGF-I gene in the rat eyes. The expression of IGF-I mRNA in the internal nuclear layer and ganglion cell layer is strong, in choroid, retinal pigment epithelium and external nuclear layer is moderate, in sclera is weak in degree and no such mRNA is detected in the cornea. The abundance of IGF-I mRNA in diabetic eye tissues is significantly (P < 0.05 or P < or = 0.01) higher than that in normal eye. These findings suggest that (1) functionally, the eye ball be considered to be an "IGF-I paracrine-autocrine system", and (2) the high expression of IGF-I indicate its initiation of diabetic retinopathy and its promotion of the progression of the lesion.

Animals↗
PubMed1995

Epidermal growth factor ligand-independent, unregulated, cell-transforming potential of a naturally occurring human mutant EGFRvIII gene.

The type III deletion-mutant gene for the epidermal growth factor receptor (EGFRvIII) is frequently expressed in glioblastomas and in breast and non-small cell lung carcinomas. To understand its contribution to the malignant phenotype in humans, we transfected NR6 cells with the mammalian vector pH beta APr-1-neo containing cDNA for either EGFRvIII or wild-type EGFR. Western blot analyses showed that NR6 transfected with wild-type EGFR (NR6W) contained a normal-sized protein (170 kilodaltons); cells transfected with EGFRvIII (NR6M) contained a truncated protein (145 kilodaltons). NR6W cells demonstrated a saturation binding curve with 125I-labeled EGF (affinity, 1.8 x 10(8); r2 = 0.96). NR6M cells, however, showed a low but consistent level of 125I-labeled EGF binding (affinity, 4 x 10(7); r2 = 0.99) compared with NR6, which lacked binding. The population doubling time was shorter for NR6M (0.64 days) than for NR6W (1.1 days) and NR6V (2.27 days). Soft agar focus formation assay by NR6M was 4- to 5-fold higher than that by NR6W. In nude mice, NR6M (1 x 10(7) cells), without exogenous ligand, formed tumors within 12 days; no tumors were observed over 90 days in mice receiving identical doses of NR6W, NR6V, or NR6 cells. EGF stimulated autophosphorylation of receptor in NR6W (4- to 9-fold) but caused only slight (1.8- to 1.9-fold) to no enhancement in NR6M. Further, there was no difference in constitutive tyrosine kinase activity between NR6M and NR6W. Our results clearly indicate that EGFRvIII functions as an oncoprotein, but its intrinsic tyrosine kinase activity may not be responsible for its biological function.

3T3 Cells↗
PubMed1994

Effects of 15-deoxyspergualin in vitro and in vivo on cytokine gene expression.

Reverse transcriptase-polymerase chain reaction showed that interleukin 3, IL-4, IL-5, IL-6, interferon-gamma and stem cell factor mRNA expression were higher in 15-deoxyspergualin-treated spleen cells than in control spleen cells. Increased IL-2 and IFN-gamma mRNA expression were observed in 15-deoxyspergualin-treated bone marrow cells. On the other hand, increased platelet counts in BALB/c-->C3H/He bone marrow chimeras were observed from days 20 to 33 in our previous work, when they were treated with 15-deoxyspergualin from days 14 to 25. In contrast, marked leukocytopenia and anemia were simultaneously observed, although a marked leukocytosis and a rapid recovery of anemia were observed on day 33 and thereafter. To analyze effects of 15-deoxyspergualin on hematopoiesis and the immune system, we examined mRNA expression in bone marrow and spleen cells from BALB/c-->C3H/He bone marrow chimeras treated with 15-deoxyspergualin from days 14 to 25. Reverse transcriptase-polymerase chain reaction showed that IL-3, IL-4, IL-6, stem cell factor, granulocyte colony-stimulating factor, and granulocyte/macrophage colony-stimulating factor mRNA expression were higher in 15-deoxyspergualin-treated chimeras than in control chimeras, indicating that these cytokines are responsible for an enhancement of hematopoiesis. It was conceivable that IL-6 supported thrombopoiesis in concert with other cytokines. On the contrary, increased IFN-gamma, IL-2, IL-3, IL-4, and IL-10 mRNA expression may play an immunosuppressive role in vivo.

Actins↗
PubMed1994

Dominant lethal mutations in the plasma membrane H(+)-ATPase gene of Saccharomyces cerevisiae.

The plasma membrane H(+)-ATPase of Saccharomyces cerevisiae is an essential protein that is required to establish cellular membrane potential and maintain a normal internal pH. An Asp-378 to Asn substitution at the residue phosphorylated during catalysis is dominant lethal when the pma1-D378N mutation is expressed along with a wild-type plasma membrane H(+)-ATPase (PMA1) gene. Several mutations in the first two putative transmembrane domains are also dominant lethal. However, these dominant lethal mutants often appear to be innocuous, because they are frequently lost by gene conversion to the wild-type sequence during the process of introducing the mutant sequence and subsequently removing the wild-type gene. Loss of the mutation by gene conversion does not occur while introducing recessive lethal mutations. Cells carrying the wild-type PMA1 gene on the chromosome and a dominant lethal mutation under the control of a GAL1 promoter on a centromere-containing plasmid exhibit a galactose-dependent lethality. Indirect immunofluorescence staining using anti-Pma1 antibodies shows that induction of dominant lethal PMA1 mutations leads to the accumulation of a number of intensely staining cytoplasmic structures that are not coincident with the nucleus and its immediately surrounding endoplasmic reticulum. These structures also accumulate the endoplasmic reticulum protein Kar2. Expression of the dominant lethal protein also prevents transport of the wild-type ATPase to the plasma membrane.

Asparagine↗
PubMed1994

Functional characterization of two human sulphotransferase cDNAs that encode monoamine- and phenol-sulphating forms of phenol sulphotransferase: substrate kinetics, thermal-stability and inhibitor-sensitivity studies.

The present paper describes the functional characterization of two human aryl sulphotransferase (HAST) cDNAs, HAST1 and HAST3, previously isolated by us from liver and brain, respectively [Zhu, Veronese, Sansom, and McManus (1993) Biochem. Biophys. Res. Commun. 192, 671-676; Zhu, Veronese, Bernard, Sansom and McManus (1993) Biochem. Biophys. Res. Commun. 195, 120-127]. These appear to encode the two major forms of phenol sulphotransferase (PST) characterized in a number of human tissue cytosols, these being the phenolsulphating (P-PST) and monoamine-sulphating (M-PST) forms of phenol sulphotransferase. HAST1 and HAST3 cDNAs were functionally expressed in COS-7 cells and kinetically characterized using the model substrates for P-PST and M-PST, p-nitrophenol and dopamine (3,4-dihydroxyphenethylamine) respectively. COS-expressed HAST1 was shown to be enzymatically active in sulphating p-nitrophenol with high affinity (Km 0.6 microM), whereas dopamine was the preferred substrate for HAST3 (Km 9.7 microM). HAST1 could also sulphate dopamine, as could HAST3 sulphate p-nitrophenol, but the Km for these reactions were at least two orders of magnitude greater than for the preferred substrates. COS-expressed HAST1 and HAST3 displayed inhibition profiles with the ST inhibitor 2,6-dichloro-4-nitrophenol (DCNP), identical with human liver cytosolic P-PST and M-PST activities respectively. Thermal-stability studies with the expressed enzymes showed that HAST1 was considerably more thermostable (TS) than HAST3, which is consistent with P-PST being termed the TS PST and M-PST being termed the thermolabile (TL) PST. Western immunoblot analyses of the expressed PST proteins using an antibody generated to a bacterially expressed rat liver aryl/phenol ST showed that HAST1 and HAST3 migrated as single proteins with different electrophoretic mobilities (32 versus 34 kDa). This is consistent with the differences in electrophoretic mobilities observed for P-PST and M-PST in a variety of tissues reported by other workers. This report on the functional characterization of P-PST and M-PST cDNAs provides important information on the structural as well as functional relationships of human PSTs, which sulphate a vast array of exogenous and endogenous compounds.

Animals↗
PubMed1994

In vivo effects of the immunosuppressant 15-deoxyspergualin on hematopoiesis in murine allogeneic bone marrow chimeras. Its thrombopoietic activity and reversal of adverse effects with granulocyte colony-stimulating factor and/or erythropoietin.

When 15-deoxyspergualin (DSG), a potent immunosuppressant, was administered into [BALB/c-->C3H/He] bone marrow chimeras from day 14 to day 25, increased thrombopoiesis was induced on day 20 to day 33, accompanied by marked leukocytopenia and anemia. The mean platelet counts in DSG-treated and control [BALB/c-->C3H/He] bone marrow chimeras on day 25 were (114.1 +/- 0.5) x 10(4)/microliter versus (58.6 +/- 2.6) x 10(4)/microliter (1.9-fold increase). Colony-forming units-megakaryocyte (CFU-Meg) were not significantly increased in DSG-treated bone marrow chimeras. Colony-forming units-granulocyte/macrophage (CFU-GM) and burst-forming units-erythroid (BFU-E) were decreased during DSG-treatment whereas CFU-Mix colony formations were rather increased, and more primitive hematopoietic progenitor cells (highly proliferative potential colony-forming units [CFU-HPP]) were not decreased in the same time period. Since CFU-GM and BFU-E colony formations were increased immediately after the cessation of DSG treatment, followed by the rebound of leukocyte counts and the recovery of hemoglobin (Hb) levels, the leukocytopenia and anemia appeared to be induced by a cytostatic effect of DSG. The adverse effect of DSG was partly reversed by the simultaneous administration of granulocyte colony-stimulating factor (G-CSF) and/or erythropoietin (EPO), suggesting the need for the administration of these cytokines in the case of bone marrow transplants treated with DSG. Furthermore, it was of note that DSG modulated hematopoiesis and stimulated the production of thrombopoietin (TPO)-like cytokine(s) as well as interleukin-3 (IL-3).

Anemia↗
PubMed1994

Appearance of a novel Ca2+ influx pathway in Sf9 insect cells following expression of the transient receptor potential-like (trpl) protein of Drosophila.

Activation of phospholipase C, elevation of free cytosolic Ca2+ concentration ([Ca2+]i) and stimulation of Ca2+ influx have been implicated in Drosophila phototransduction. Electrophysiological studies suggest that trp and trpl proteins may be important for the light-activated Ca2+ current found in Drosophila photoreceptor cells. Although these proteins exhibit homologies to voltage-gated Ca2+ and Na+ channels, their actual function in insect cells and their relation to proteins involved in mammalian cell Ca2+ signaling remains unknown. In the present study, [Ca2+]i was examined in fura-2-loaded Sf9 insect cells infected with recombinant baculovirus containing cDNA for the trpl protein. Ca2+ influx was examined by use of Ba2+, a Ca2+ surrogate that is not a substrate for Ca(2+)-pumps or carriers and by measurement of whole-cell membrane currents. The results suggest that expression of trpl is associated with appearance of a Ca2+ permeable, non-selective cation channel formed by the trpl protein.

Animals↗