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Biomedical subjects

J Hu

Publications and source records attributed to J Hu.

At least 379 records · Page 21Linked to original sources
PubMed1998

Interferon-gamma inhibits the steroidogenic acute regulatory protein messenger ribonucleic acid expression and protein levels in primary cultures of rat Leydig cells.

Interferon-gamma (IFNgamma) is an immunomodulating cytokine that has profound effects on reproductive function. IFNgamma inhibits steroidogenesis both in vivo and in vitro. The mechanism by which IFNgamma inhibits Leydig cell steroidogenesis remains unclear. In the present study, we evaluated the effect of IFNgamma on the expression and regulation of the steroidogenic acute regulatory protein (StAR) gene in primary cultures of rat Leydig cells. StAR facilitates the efficient production of steroid hormone by regulating the translocation of cholesterol from the outer to the inner mitochondrial membrane, the site of the cytochrome P450 side-chain cleavage (P450scc) enzyme system that converts cholesterol to pregnenolone. IFNgamma inhibited hCG-induced StAR messenger RNA (mRNA) levels in a dose-dependent manner. The addition of IFNgamma in a concentration of 500 U/ml decreased hCG-induced 3.8- and 1.7-kilobase StAR mRNA by 78% and 70%, respectively. IFNgamma also reduced hCG-stimulated P450scc mRNA levels by 69%. The inhibitory effects of IFNgamma on StAR mRNA levels were confirmed by ribonuclease protection assay. As early as 12 h after the addition of IFNgamma, hCG-induced StAR mRNA levels decreased by more than 44%. To evaluate the effects of IFNgamma on StAR protein levels, Western blot analyses were performed. hCG in a concentration of 10 ng/ml increased StAR protein by 5.6-fold. Treatment of Leydig cells with IFNgamma (500 U/ml) decreased hCG-induced StAR protein by 44%. In contrast, interleukin-1 and murine tumor necrosis factor-alpha reduced hCG-induced P450scc mRNA expression without inhibiting StAR mRNA or protein levels. In conclusion, IFNgamma inhibits Leydig cell steroidogenesis by down-regulating StAR gene expression and protein production.

Animals↗
PubMed1998

Expression and regulation of interferon-gamma-inducible protein 10 gene in rat Leydig cells.

In the present study, we report the cloning of a gene that is differentially expressed in normal adult rat Leydig cells and whose expression is inhibited by hCG but is induced by interferon-gamma (IFNgamma). DNA sequence analysis identified this gene as rat IFNgamma-inducible protein 10 (IP-10), a member of the -C-X-C- chemokine superfamily of proinflammatory cytokines. High levels of IP-10 messenger RNA (mRNA) were constitutively expressed in freshly isolated and primary cultured Leydig cells. hCG inhibited this expression in a dose-dependent manner. The addition of 1 ng/ml hCG inhibited IP-10 mRNA levels more than 80%. Conversely, IP-10 mRNA levels were markedly increased in response to murine interleukin-1alpha, murine tumor necrosis factor-alpha, and murine IFNgamma by 3.3-, 10-, and 26-fold, respectively. Concomitant addition of murine interleukin-1alpha, murine tumor necrosis factor-alpha, and murine IFNgamma synergistically increased IP-10 mRNA levels by 58-fold. Furthermore, in addition to one previously described rat IP-10 mRNA transcript (1.5 kb), another larger transcript (2.7 kb) was identified by Northern blot in rat Leydig cells. After screening a rat testis complementary DNA library, we obtained a partial structural gene and an intron sequence, which possibly originated from the larger transcript of rat IP-10 mRNA. Histochemical and immunocytochemical staining revealed that purified cells were positive for 3beta-hydroxysteroid dehydrogenase and IP-10, confirming that IP-10 is indeed present in Leydig cells. IP-10 antisense oligonucleotides enhanced basal and hCG-induced testosterone formation. This suggests that endogenous IP-10 has an inhibitory effect on Leydig cell steroidogenesis. In conclusion, IP-10 is expressed in rat Leydig cells and may have paracrine and autocrine effects on testicular function.

Animals↗
PubMed1998

Upregulation of human chorionic gonadotrophin-induced steroidogenic acute regulatory protein by insulin-like growth factor-I in rat Leydig cells.

Insulin-like growth factor-I (IGF-I) plays an essential role in reproductive function. Leydig cells express specific IGF-I receptors, and IGF-I enhances human chorionic gonadorphin (hCG)-induced testosterone formation. In the present study, we evaluate the effect of IGF-I on the gene expression and protein levels of steroidogenic acute regulatory protein (StAR), the rate-limiting step in steroidogenesis. StAR mRNA is expressed in rat Leydig cells as two major transcripts of 3.8 and 1.7 kb. StAR mRNA levels (both 3.8 and 1.7 kb) were markedly induced about 20-fold by hCG (10 ng/mL). Concomitant addition of IGF-I (50 or 100 ng/mL) and hCG (10 ng/mL) resulted in significant increases in StAR and cytochrome P450 side-chain cleavage (P450scc) mRNA levels, whereas lower doses of IGF-I (1 or 10 ng/ mL) had small effects. Synergistic effects of IGF-I and hCG on StAR mRNA levels were confirmed by ribonuclease protection assay (RPA). IGF-I (100 ng/mL) enhanced hCG- and 20 OH-cholesterol + hCG-induced testosterone formation, whereas the conversions of pregnenolone, 17-OH pregnenolone, dehydroepiandrosterone, and androstenedione to testosterone were not affected. This suggests that the major effect of IGF-I is at the steps of StAR and P450scc, whereas other steroidogenic enzymes are not affected. To evaluate whether increased StAR mRNA levels induced by IGF-I and hCG are associated with increased StAR protein levels, we carried out Western blot analyses. Basal StAR protein levels were low after 24 h in culture. hCG (10 ng/mL) increased StAR protein by 4.5-fold. In the presence of IGF-I (100 ng/mL), hCG-induced StAR protein levels were further increased. In conclusion, our present study demonstrated that IGF-I enhances Leydig cell steroidogenesis by upregulating hCG-induced StAR gene expression and protein production.

Animals↗
PubMed1998

[Experimental study of the effect of danshen on the viability of burned skin].

In order to investigate the influence of Danshen on the viability of skin from II degree burned and the effect of Danshen on the wound healing, 20 rabbits having a wound from second degree burn were divided into two groups randomly. The experimental group was treated with Danshen and the control was treated with normal saline. Then succinate dehydrogenase, SDH activity, malonyl dialdehyde, MDA concentration, water content and morphological change of wound tissue were observed dynamically. The results showed that the levels of SDH activity in the experimental group were significantly higher than that of the control group (P < 0.05), the MDA concentration and water content of the former were lower than that of the latter (P < 0.05) and the morphological examination showed that the wound healing process of former were better than that of the latter. The conclusion was Danshen had a beneficial effect on the viability of the burned skin and this effect was due to its protecting the residual epithelial cells of the burned skin.

Animals↗
PubMed1998

Acupuncture treatment of migraine in Germany.

1. The fact that 25% of the German population have the problem of headache, or migraine is uniquely characteristic of Germany. The administration of analgesics which used to be their local treatment for the problem can neither give a radical cure nor avoid certain side effects. 2. It can be seen from the therapeutic result of a 80% effective rate in 89 cases of migraine that acupuncture treatment is an effective therapy for "German migraine" without any side effects. 3. Since 10% of the migraine cases were related to the improper sleeping posture, due attention should be paid and appropriate measures be taken to prevent occurrence of headache. 4. While receiving acupuncture treatment, the cases of migraine related to menstruation should also try to regulate their emmeniopathy. 5. It seems somewhat difficult for acupuncture treatment to give good effects in those with migraine related to psychological pressures and in those given long-term administration of contraceptives. This needs to be further studied.

Acupuncture Analgesia↗
PubMed1998

Clinical observation on 25 cases of hormone dependent bronchial asthma treated by acupuncture.

The clinical observation revealed that the asthmatic symptoms in most of the patients began to be improved after several acupuncture treatments with the dosage of the drug gradually reduced. Generally, the dose of cortisone per os was decreased by 2 mg every 10 days, while that of aerosol was controlled by the patients themselves according to the condition of the disease. The symptoms in most of the patients were markedly improved after 15 treatments, but the treatment should be continued for another 10 times to consolidate the curative effect. Thus, each asthmatic patient needs to receive approximately 30 sessions of acupuncture treatment, lasting about 3 months. Thereafter, in order to prevent its relapse, the treatment should be administered 10 times each year in the summer season. It is worthy to be mentioned that, in this series, there was a female patient who suffered from anaphylactic asthma induced by dog's hair. She received 10 sessions of acupuncture treatment with no any improvement. In this case, the acupuncture treatment should not be given any longer. There were another two children patients aged 5 and 7 years respectively, for them the above method of acupuncture treatment was difficult to be used. Therefore, the auricular pressing method combined with cupping was adopted instead. The auricular points selected were Shenmen, Lung, Large Intestine, sensitive point, Pingchuan, Subcortex, and Kidney. 5 points were used each time, and pressed with the seeds of Vaccaria which were changed every 3 days. The patients were asked to press each of the points themselves 3 times a day (each time by 20 pressings). And Dazhui (Du 14), Feishu (UB 13), Pishu (UB 20) and Shenshu (UB 23) were cupped for 5 min. each time. The auricular pressing and cupping therapies may also be added for adult patients to strengthen the curative effect. The 25 cases of hormone dependent bronchial asthma were treated by acupuncture, yielding a markedly effective rate of 56% with a total effective rate of 96%, indicating that good therapeutic results can also be expected in the western countries for those cases who have already been treated with hormones.

Acupuncture Therapy↗
PubMed1998

[Open heart surgery without cross clamping aorta].

Open heart surgery without cross clamping aorta under normothermic or hypothermic cardiopulmonary bypass was performed in 167 patients in which there were more than ten kinds of cardiac diseases. The characteristics of the procedure included only vena cava blocked and aorta unclamped with beating heart or artificial evoked ventricular fibrillation. It diminished myocardial ischemia and reperfusion injuries maximally. There were no low cardiac output syndrome, severe arrhythmia and complications of brain except two patients died postoperatively. The operative mortality rate was 1.1% (2/167). The advantages, disadvantages and safety of this method are discussed briefly in this paper.

Adolescent↗
PubMed1998

[Influence of ischemic preconditioning of heart on ischemia/reperfusion injury of rabbit lung].

The influence of ischemic preconditioning of heart on ischemia-reperfusion injury of 16 Japanese big-ear-rabbit lungs were studied. The results showed: 1. Experimental group had a significant reduction in wet/dry weight ratio; 2. It had a significant increase in PaO2. 3. It had a minimal intraalveolar neutrophil infiltration in comparison with the control group. These data suggestes that the ischemic preconditioning of heart can lighten the ischemia-reperfusion injury of rabbit lungs.

Animals↗
PubMed1998

[CCD-diode array spectrophotometry used for simultaneous determination of cadmium and lead].

A new spectrophotometric setup for simultaneous determination of lead and cadmium has been developed. It is composed of charge coupled device (array detector), multichromatic instrument and computer. The optimum chromogenic conditions of meso-tetra (4-trimethylammoniumphenyl) porphine (TAPP) with cadmium and lead were studied and reported in this paper. The linear ranges of Pb and Cd were 0-0.50 microgram/ml and 0-0.20 microgram/ml respectively. The detection limits were 0.001 microgram/ml for both Pb and Cd. The proposed method has been successfully applied to the simultaneous determination of cadmium and lead in the synthetic samples and the soaking solutions of ceramics and enamel. The recoveries of spiked samples ranged from 84.4%-118.6% and the average recovery was 100.8% with RSD of 1.0%-9.1%. The proposed method is more sensitive, more accurate and faster than the traditional one, it can be used to simultaneously determine multiple elements.

Cadmium↗
PubMed1998

[Randomized comparative study of GyneFix IN and TCu 380A intrauterine devices].

OBJECTIVE: To observe the clinical performances of the new intrauterine device (IUD)-GyneFix IN. METHODS: The present study is a randomized comparative clinical trial. 607 healthy parous women were randomly allocated into GyneFix IN group (n = 302) or TCu 380A group (n = 305). IUD was inserted during the menstrual interval by the trained investigators. Follow-up were arranged at 1, 3, 6 and 12 months after insertion. The discontinuation rates were calculated by life table method. RESULTS: At the end of the first year, there was no pregnancy occurred in GyneFix IN group. Its expulsion rate and removal rate for medical reasons were 2.67 and 1.02 per 100 women respectively. The use-related discontinuation rates was 3.66, which was significantly lower than that in the TCu 380A group (7.88, P < 0.05). The number of women with complaint of pain was also less in GyneFix IN group. CONCLUSION: The excellent performance of the new IUD which is a frameless device with high copper surface and anchoring system was confirmed by this multicentre trial. Due to lower expulsion rate and less side effect of pain, it could be recommended.

Adolescent↗
PubMed1998

[Total cavo-pulmonary connection for complex congenital heart disease].

Between April 1994 and January 1997, 10 patients with complex congenital heart disease were treated with total cavo-pulmonary connection(TCPC). They included 7 males and 3 females, aged 2-17 years(mean 10.1 years). These cases were single ventricle in 5, tricuspid atresia in 4, severe Ebstein anomaly in 1. For construction of the right atrial lateral tunnel, Gore-Tex patch was used in 9 cases and autologous right atrial wall in another, 4 of the 10 patients underwent TCPC without aortic crossclamping. There were no operative deaths. The follow-up is 2-36 months(mean 12.3 months). All of these patients did well and were in NYHA class I. The advantages, operative indication and technique of TCPC and the experience of improvement of surgical results are briefly discussed in this paper.

Adolescent↗
PubMed1998

[Construction of retrovirus vector of bcr/abl mRNA cleaving ribozyme gene and its effects on K562 cells].

OBJECTIVE: To investigate the effect of bcr/abl fusion gene on the growth of chronic myeloid leukemia(CML) cells and to explore the feasibility of ribozyme in CML gene therapy. METHODS: A hammerhead ribozyme DNA targeting the bcr/abl (b3a2) transcript was synthesized, and recombinated into retroviral vector pLXSN forming pLRZXSN recon. By lipofectin mediated DNA transfection technique, pLRZXSN was introduced into K562 cells. The effects of the ribozyme on the growth of K562 cells and apoptosis were studied by leukemic colony assay, flow cytometry (FCM), reverse transcript-polymerase chain reaction (RT-PCR), detection of DNA fragmentation and electron microscope. RESULTS: 1. The number of K562 cell colony was inhibited by 85% after the cells were transfected for 48 hours. 2. The expression of bcr/abl mRNA and the fusion protein P210 was decreased sharply in K562 cells transfected with pLRZXSN for 48 and 72 hours, respectively. 3. The characteristics of apoptosis was revealed in K562 cells transfected with pLRZXSN, i.e. sub-G1 peak, DNA fragmentation and morphological changes. CONCLUSION: The ribozyme was capable of inhibiting the proliferation of K562 cells and inducing the cell apoptosis.

Apoptosis↗
PubMed1998

[Multicentre, randomized, prospective and comparative study of ceftriaxone, cefotaxime and cefuroxime in treating mild to moderate respiratory tract infection].

OBJECTIVE: The objective of this multicentre, randomized, prospective and comparative study was to evaluate and compare the efficacy and safety of 1 g intravenous ceftriaxone (active ingredient of Rocephin), 3 g intravenous cefoiaxime (active ingredient of clafron), and 2.25 g intavenous cefuroxime (active ingredient of Zinacef). METHOD: In this multicentre, randomized, prospective and comparative study, patients received 1 g of ceftriaxone intravenously once a day (group A), or 1 g of cefotaxime intravenously three times a day (group B), or 0.75 g of cefuroxime intravenously three time a day (group C). 197 patients were enrolled in the study, and in 142 (48 in group A, 46 in group B and 48 in group C) we were able to make an evaluation. RESULT: The overall efficacy (bacteriological eradication plus clinical cure or clear improvement) of ceftriaxone, cefotaxime and cefuroxime were 81%, 83%, 79% respectively (P > 0.05). The eradication rate for three groups were 80%, 78%, 75% (P > 0.05). No adverse events occured. CONCLUSION: Data obtained in our study indicate that for the majority of patients with lower respiratory tract infections, 1 g ceftriaxone, 3 g cefotaxime and 2.25 g cefuroxime are effective and safe, and 7 days therapy is enough, but the use of 1 g ceftriaxone is more convenient.

Adolescent↗
PubMed1998

[Polymorphism analysis of D6S366 STR locus].

The polymorphic STR locus D6S366 was analyzed using PCR and PAG electrophoresis and 7 alleles were detected from 200 unrelated individuals in Wuhan. The allete distribution of the locus was in accordance with Hardy-Weinberg equilibrium. The H, Dp, P, E, and PIC of the D6S366 were calculated in this paper.

Alleles↗
PubMed1998

[Study on comprehensive assessment in selection of special work personnel].

A comprehensive assessment method combining fuzzy set theory with traditional approaches is introduced. Method of index assessment and comprehensive assessment along with a fuzzy assessment model are presented. As an example, three fuzzy algorithms are used to assess 6 candidates. Calculated results show that the combination of fuzzy logic and experience of experts is feasible and can deal with unprecise information more effectively as well as the aggregation of fuzzy information and precise data. The new method described in this paper is accurate and the speed of decision-making is much improved as compared with the conventional approaches.

Aerospace Medicine↗
PubMed1998

[Morphological characteristics of fruits and seeds of Chinese Caesalpinia and its taxonomic significance].

OBJECTIVE: To set up a toxonomic approach to the morphological characteristics of fruits and seeds of Chinese Caesalpinia. METHOD: The ripe fruits collected in the field are dried in the shade, are surveyed and described and the fruit's and seed's morphological characteristics. RESULT: The interspecific differences of morphological characteristics among the fruits and seeds are obvious. The characteristics are stable. A key for their identification is given. CONCLUSION: The above approach can be used as the taxonomic criteria for species differentiation.

Caesalpinia↗
PubMed1998

[Study on the rifampicin polylactic acid microspheres for lung targeting].

In this paper, the effects of different variables on the preparation of polylactic acid microspheres (PLA-MS) were studied. The optimized preparation conditions of rifampicin polylactic acid microspheres (RFP-PLA-MS) were aquired through orthogonal test. The paddle method was used to study the drug release properties of RFP-PLA-MS. Stability of RFP-PLA-MS at different temperatures was also studied. Pharmacokinetic and tissue distribution of RFP-PLA-MS after intravenous administration were carried out in rabbits. The experiments revealed that the RFP-PLA-MS was regular in its morphology with a mean diameter of 9.00 +/- 4.08 microns. The drug loading was 16.0% and encapsulation efficiency was 31.9%. The release properties could be expressed by the following equation: Q = 20.77 + 10.12 T 1/2 (gamma = 0.9892). The RFP-PLA-MS was stable after stored at 4 degrees C and room temperature under desiccated condition for three months. RFP-PLA-MS showed a combination of lung targeting and sustained drug release in experiments on rabbits.

Animals↗