Biomedical subjects

Ji-Hong Liu

Publications and source records attributed to Ji-Hong Liu.

34 records · Page 2Linked to original sources

PubMed2003

[The relaxation effects of tetrandrine on the corpus cavernosum tissue of rabbit in vitro].

OBJECTIVES: To study the relaxation effects of tetrandrine on the corpus cavernosum tissue of rabbit in vitro. METHODS: 1. The fluctuation of the dose-response relaxation curves for the contraction of KCl induced by tetrandrine was observed with isolated rabbit corpus cavernosum tissue. 2. Isolated strips of rabbit corpus cavernosum tissue were precontracted with 10 mumol/L phenylephrine(PE). Relaxation in response to cumulative doses of tetrandrine was determined in the absence and presence of nitric oxide synthase inhibitor (L-NNA) and soluble guanylate cyclase inhibitor (methylthioninium). RESULTS: 1. The dose-response curves of KCl were shifted to the right nonparallelly, and the maximal responses were depressed to (73.0 +/- 3.8)% and (41.5 +/- 3.4)%, respectively, in the presence of tetrandrine(10 mumol/L, 30 mumol/L). 2. On rabbit cavernosal muscle stripes precontracted with PE(10 mumol/L), increasing concentrations of tetrandrine (1 mumol/L, 10 mumol/L, 30 mumol/L and 100 mumol/L) showed dose dependent relaxation [(6.0 +/- 1.4)%, (21.3 +/- 2.2)%, (47.4 +/- 3.3)%, and (68.1 +/- 3.6)%, P < 0.01]. However, in the meantime, it was found that these relaxation effects were not affected by the presence of L-NNA and methylthioninium (P > 0.05). CONCLUSIONS: Tetrandrine was effective in relaxing rabbit corpus cavernosum tissue in vitro in a dose-dependent style. The mechanism might be related with its blocking effect on calcium channel, but not the NO-cGMP passage.

Alkaloids↗

PubMed2003

[Effects of tetramethylpyrazine on cytosolic free calcium concentration in penis corpus cavernsum smooth muscle cells in rabbits].

OBJECTIVE: To study the effects of Chinese medicine tetramethylpyrazine (TMP) on intracellular free calcium ([Ca2+]i) in cultured penis corpus cavernosum smooth muscle cell (PCSMC) in rabbits. METHODS: By using laser scanning confocal microscope (LSCM), the [Ca2+]i fluorescence signal changes was investigated in cultured PCSMC loaded with Ca2+ indicator Fluo-3/AM and divided into potassium chloride(KCl) group and norepinephrine (NE) group. Compared with verapamil (Ver), the effects of TMP was observed in different concentrations on [Ca2+]i increase induced by high potassium and NE. RESULTS: TMP had no obvious effect on resting PCSMC [Ca2+]i. It was found that 1, 10, 100 mumol/L TMP significantly inhibited [Ca2+]i increase induced by high potassium-depolarization. The peak inhibition rates were (38.6 +/- 3.0)%, (44.1 +/- 2.4)% and (53.7 +/- 4.1)% respectively. TMP could also inhibit cytosolic calcium pool release induced by 1 mumol/L NE. The peak inhibition rates were (13.9 +/- 2.7)%, (21.2 +/- 1.9)% and (29.5 +/- 3.6)% respectively. CONCLUSIONS: TMP can inhibit rabbit PCSMC [Ca2+]i significantly by suppressing voltage-dependent calcium channel and cytosolic calcium pool release. The effect, similar to Ver, signifies the important mechanism of erectile dysfunction (ED) therapy.

Animals↗

PubMed2003

[How to increase the optimal rate of secondary cytoreductive surgery in recurrent epithelial ovarian cancer].

BACKGROUND & OBJECTIVE: Optimal secondary cytoreduction is of prognostic importance for recurrent epithelial ovarian cancer. To increase the optimal rate of secondary cytoreductive surgery in these patients is helpful for improving the prognosis of recurrent epithelial ovarian cancer patients. In this retrospective study, we investigated how to increase the optimal rate of secondary cytoreductive surgery in recurrent epithelial ovarian cancer patients. METHODS: The clinical data of 54 patients with recurrent epithelial ovarian cancer were analyzed retrospectively, who received secondary cytoreductive surgery during March 1 1997 to March 31 2003 in Cancer Center, Sun Yat-sen University. Nineteen patients had tumors only in pelvis, and 35 patients both in pelvis and abdomen. Single tumor was found in 16 patients and multiple tumors in 38 patients. Thirty-eight patients had ascites and 16 patients no ascites. Preoperative chemotherapy was given to 20 cases, and responses were observed in 12 patients and no response in 8. Multivariate logistic regression was carried out to investigate the relationship of residual diseases of secondary cytoreduction with age, time to recurrence, recurrent sites, ascites, and preoperative salvage chemotherapy. RESULTS: Optimal surgical cytoreduction was obtained in 81.5% (44/54) of the patients, with no macroscopic residual diseases in 53.7% (29/54) and residual diseases <or=2 cm in 27.8% (15/54). Logistic regression showed that recurrent sites and ascites were the significant factors for residual diseases after secondary cytoreductive surrey (both P <or= 0.05). Optimal cytoreduction was obtained in 100% (12/12) of the patients whose salvage chemotherapy before secondary cytoreduction was effective and in 37.5% (3/8) cases whose chemotherapy before secondary cytoreduction was ineffective (P<or=0.05, Chi(2) test). Complicated surgical procedures involving gastrointestinal tract, urinary tract, liver or spleen were carried out in 40.7% (22/54) of the patients. Post-operation complications occurred in 16.6% (9/54) and post-operation death rate was 1.9% (1/54). CONCLUSION: It could be helpful for obtaining optimal secondary cytoreduction and avoiding helpless laparotomy to select patients properly according to the border of recurrent tumor, recurrent site, with or without ascites and the response of salvage chemotherapy before secondary cytoreduction and to do careful preoperative preparations.

Adult↗

PubMed2003

[Analysis of risk factors for epithelial ovarian cancer recurrence].

BACKGROUND & OBJECTIVE: Advanced ovarian cancer shows a high recurrence and poor survival rate. It is important to identify the risk factors for the recurrence of ovarian cancer, due to the lack of reliable methods for the detection of early disease. This study was designed to explore the risk factors for the recurrence of epithelial ovarian cancer. METHODS: Factors that might be related to the recurrence of 109 epithelial ovarian cancer patients including age, pathological type, FIGO stage, operation type, chemotherapy regimen, neoadjuvant chemotherapy, postoperative chemotherapy cycles, first operation status, and size of residual tumor were analyzed by logistic regression model using SPSS 10.0 statistical software. RESULTS: Of 109 patients with ovarian cancer, 36 (33%) relapsed after a combination of surgery and chemotherapy, and the median recurrence-free interval was 19 months. The 5-year survival rates were 62.7% and 43.3% for the 109 patients and the recurrent patients, respectively. The survival rates of pelvic recurrence (50.1%) and extra-pelvic recurrence (36.1%) were not statistically different. Univariate analysis showed that the risk of recurrence in mucous adenocarcinoma or FIGO stage I patients were lower than that of other pathology type or FIGO stage (beta=-1.565 and -1.799,P=0.0120 and 0.026 ) while it was higher in the patients given above 8 cycles chemotherapy than those given 1-4 or 6-8 cycles(beta=-3.591 and -1.500,P< 0.001 and =0.038). Multivariate analysis showed that histological type, FIGO stage and postoperative chemotherapy cycles had remarkable influence on the relapse of epithelial ovarian cancer independently(RR=3.473, 4.713, and 6.140, respectively, P< 0.05). CONCLUSION: Histological type, FIGO stage, and postoperative chemotherapy cycles influence the recurrence of epithelial ovarian cancer. Since FIGO stage is a remarkable risk factor for the recurrence, early diagnosis should be the key point to decrease it. Reasonable chemotherapy plan is essential for the therapy of ovarian cancer, but excessive chemotherapy is not good for effectiveness.

Adolescent↗

PubMed2003

[Tumor infiltrating dendritic cells and Mucin1 gene expression in benign prostatic hyperplasia and prostate cancer].

OBJECTIVE: To study the expression of Mucin1 gene and tumor infiltrating dendritic cells(TIDC) in the tissues of benign prostatic hyperplasia (BPH) and prostate cancer. METHODS: Mucin1 and TIDC were detected in 20 specimens of BPH and 30 specimens of prostate cancer by immunohistochemistry SP method. RESULTS: MUC1 expressed in both prostate cancer and BPH. The staining patterns were significantly associated with tumor pathological grade (P < 0.001). The number of TIDC was negatively correlated with tumor pathological grade, the higher the grade, the smaller the number of TIDC (P < 0.001). CONCLUSIONS: The expression pattern of MUC1 and the number of TIDC could be considered as useful markers to evaluate the malignant degree and prognosis of prostate cancer. The decrease of TIDC plays an important role in tumor immune evasion and immune tolerance. Highly expressed MUC1 could lead to the failure of hormonal treatment for prostate cancer, and contribute much to tumor infiltration and metastasis.

Antigens, Neoplasm↗

PubMed2003

[Animal models for erectile dysfunction researches].

Knowledge about the physiology, pathophysiology and pharmacology of human erection is mostly obtained through researches on animals and animal models. However each animal or animal model has its own advantages and limitations and no single animal model completely satisfies all studies. The credibility of the research results primarily lies on the rational selection of animal models. So it is very important to recognize the characteristics of every animal and animal model and select appropriate models for studies. This article is meant for a review: the characteristics of the animals widely used for erectile dysfunction researches, the selection of appropriate animals for researches, and the methods and mechanisms of making the animal models of the clinically ever-present kinds of erectile dysfunction.

Animals↗

PubMed2003

[Advances in studies of Chinese herbs for improving relaxability of corporal smooth muscle].

Erectile dysfunction (ED) is a commonly and frequently encountered disease among middle-aged and old males. The traditional Chinese medicine has a long history of medical treatment for ED has been focusing too much on clinical experience researches, without obtaining sufficient evidence for the curative effect of related traditional medicines. Recently, with important breakthroughs the researches on the molecular biochemical mechanisms of erection, sildenafil(Viagra), a phosphodiesterase type 5 (PDE5) inhibitor, has been developed, and exciting progress achieved in the treatment of ED with Chinese herbal medicine and the presentation of the pharmacological mechanism. This article presents an overview on recent advances in the studies of ED treatment with traditional Chinese medicine.

Animals↗

PubMed2003

[Experience of treating Peyronie's disease by plaque thinning with carbide burs and improved Nesbit technique].

OBJECTIVE: To investigate the efficacy of plaque thinning with carbide burs and improved Nesbit technique in the treatment of Peyronie's disease. METHODS: Follow-up studies were made on 11 patients with Peyronie's disease treated by plaque thinning with carbide burs and the improved Nesbit technique. RESULTS: Satisfactory results were achieved in all the cases. Nine cases without ED could now complete sexual intercourse. Of the 8 cases with penile curvature, only 2 failed to be completely corrected. And of the 5 cases with erectile pain, only 2 still had slight intermittent pain during erection. However, neither the incompletely corrected curvature nor the slight intermittent pain affected the patients' sexual life. CONCLUSIONS: Plaque thinning with carbide burs and improved Nesbit technique for the treatment of Peyronie's disease have many advantages, such as easy manipulation, good short-term results, few complications, and rare recurrence, while its long-term results are not yet clear.

Adult↗

PubMed2003

[The effect of calcium channel blocker on human sperm].

Calcium ion exists extensively in cells as the second messenger, and calcium channel blocker (CCB) is widely used to treat cardiac, skeletal muscular diseases. With the advances in the investigation of human sperm calcium channel, CCB has been proved to affect not only the shape, activation and acrosome reaction, but also the function of human sperm, which may afford a new approach to male contraception.

Calcium Channel Blockers↗

PubMed2002

Influence of several uropathogenic microorganisms on human sperm motility parameters in vitro.

AIM: The effects of certain uropathogenic microorganisms (Neisseria gonorrhoeae, Staphylococcus aureus, Staphylococcus epidermidis and Mycobacterium tuberculosis) on human sperm motility characteristics were studied in vitro. METHODS: In 10 healthy fertile men, ejaculates were aseptically obtained by masturbation and with a swim-up technique, a sperm suspension of high motility and purity was obtained. Several uropathogenic bacteria were obtained from outpatients with genitourinary tract infections. The sperm suspension was incubated with the pathogens at a bacteria: sperm ratio of 50:1 at 37deg. The sperm mobility parameters were estimated with a computer-assisted sperm analyzer (CASA) provided with a multiple-exposure photography system (Madi Corp., Zhejiang, China). Measurements were carried out at 0, 2 and 4 hours of incubation. RESULTS: Staphylococcus aureus significantly decreased the sperm motility and viability, but Staphylococcus epidermidis, Mycobacterium tuberculosis and Neisseria gonorrhoeae did not. CONCLUSION: Staphylococcus aureus has an inhibitory effect on human sperm motility in vitro.

Gonorrhea↗

PubMed2002

Detection of Epstein-Barr virus in human colorectal cancer by in situ hybridazition.

OBJECTIVE: To investigate the relationship between Epstein-Barr virus (EBV) and the pathogenesis of human colorectal cancer. METHODS: The small-molecule RNA fragments of EBV was examined by in situ hybridization in colorectal cancer specimens obtained from 130 patients. RESULTS: EBV was found in the 6 of 130 colorectal cancer cases. EBV positivity was more prevalent in male patients (4/6), and the tumor tissues of the 4 EBV-positive cases were featured by obvious stromal infiltration by the lymphocytes (4/6). CONCLUSION: EBV infection might be related to the pathogenesis of some colorectal adenocarcinomas in China, and intensive lymphocyte infiltration in the stroma of the tumor tissues can be an important pathological indication of EBV infection in colorectal tumors.

Adult↗

PubMed2002

[Biological characteristics of rabbit corporal smooth muscle cells cultured in vitro].

OBJECTIVES: To study the biological characteristics of rabbit corporal smooth muscle cells (SMC) cultured in vitro. METHODS: In vitro tissue culture technique, morphological observation, cell counting, mitosis index and adhesion rate evaluation were applied to study the biological features of the SMC. RESULTS: 1. SMC were spindle-shaped and parallel along their longitudinal axis, showing obvious orientation. 2. The attachment and the proliferation of SMC in vitro were rapid. SMC cultured in vitro can grow and maintain their steady characteristics provided appropriate passage rate and culture condition. CONCLUSIONS: The SMC cultured in vitro are proved to be used to evaluate and investigate the effect of some medicine on penile erection.

Animals↗

PubMed2002

[Intercellular gap junctions in corporal smooth muscle].

The contractility of corporal smooth muscle plays a critical role in human penile erectile process. Understanding the initiation, maintenance and modulation of corporal smooth muscle tone is a prequisite to improve understanding, diagnosis and treatment of erectile dysfunction. Despite this fact, indentification of both the precise mechanistic basis by which various agents exert their effects on individual corporal smooth muscle cells, moreover, the process by which these signals are spread among the diverse array of parenchymal cells in the paired corporal, remain somewhat of a physiological enigma. Therefore, this article aims at: 1. to review current knowledge of the regulation of corporal smooth muscle tone at the cellular and molecular level; 2. to review various methods used in the study of gap junction channel.

Animals↗

PubMed2002

[Influence of protein kinase C on motility and acrosome reaction of sperm].

Protein kinase C (PKC) is localized in the equatorial segment and the principal piece of the tail of spermatozoa. Activator of PKC results in increasing flagellar motility of sperm that is blocked by PKC inhibitors such as staurosporine. A good correlation (r = 0.9, P < 0.001) is found between the content of PKC in sperm and sperm motility. Zona pellucida (ZP) stimulates the spermatozoa binding the acrosome reaction resulting in the release of hydrolytic enzymes and in the exposure of new membrane domains. ZP binding to receptors in the plasma membrane can regulate adenyl cyclase (AC) leading to elevation of cAMP and protein kinase A (PKA) activation. The PKA activates a voltage-dependent Ca2+ channel in the outer acrosomal membrane which releases Ca2+ from the interior of the acrosome to the cytosol. Activation of the PLC resulted from the rise in Ca2+ hydrolyze phosphatidyl inositol bisphosphate. The product activate PCK to open a voltage-dependent Ca2+ channel (L) in the plasma membrane, leading to the second (II) Ca2+ higher increase which result in membrane fusion and acrosome reaction. It is proposed that PKC would be involved in the regulation of motility and acrosome reaction of sperm.

Acrosome Reaction↗

PubMed2002

[Influence of dibutyryl cyclic adenosine monophosphate on motility of sperm].

OBJECTIVES: To investigate the influence of cAMP/PKA signal transduction on human sperm motility, and to study the effect of dibutyryl cyclic adenosine monophosphate dibutyryl cyclic adenosine monophosphate (dbcAMP) on human sperm motility in vitro. METHODS: Sperm aseptically obtained by masturbation and prepared by swim-up technique from 10 healthy fertile men were incubated with different concentrations of dbcAMP. Measurement of mobility were carried out at 20, 30, and 60 min in all specimens. RESULTS: The sperm treated with dbcAMP showed a significant increase in sperm progressive motility and the percentage of motile cells. The effect seemed enhanced with the increasing of dbcAMP concentration. VSL and VCL were not affected by dbcAMP. CONCLUSIONS: dbcAMP can activate the mobility of human sperm in vitro.

Adult↗

PubMed2002

[Influence of male genital bacterial infection on sperm function].

Male infertility is related to urogenital tract bacterial infection. The significance of bacteriosperimia for male infertility has been paid attention in recent years. Asymptomatic bacteriosperm may play an important role. However, litter is known about the adverse influence of some uropathogenic bacteria on sperm function. The article reviewed some uropathogenic bacteria in male urogential tract and several pathomechanisms of effect bacteria on sperm function.

Bacteria↗