[Synergism of three risk factors in hepatocellular carcinogenicity]

To evaluate potential synergistic effects of aflatoxin B1 (AFB1) hepatitis B virus (HBV) and hepatitis C virus (HCV) in the development of human primary hepatocellular carcinoma (PHC), AFB1, HBV-DNA and HCV-RNA in liver tissue sampled from the patients with PHC were detected by high performance liquid chromatography, nested polymerase chain reaction (PCR), and reverse transcription nested PCR. Positive rates of AFB1, HBV-DNA and HCV-RNA were 67.7% (21/31), 88.2% (60/68) and 13.2% (9/68), respectively. Eighteen of the 31 patients were positive for both AFB1 and HBV-DNA, and six of the 68 patients positive for both HBV-DNA and HCV-RNA. Furthermore, AFB1, HBV-DNA and HCV-RNA all were detected in four cases, while all negative in controls. It suggests that all the three factors are directly associated with human hepatic carcinoma, and play a synergistic role on hepatic carcinogenicity.

Accelerated deamination of cytosine residues in UV-induced cyclobutane pyrimidine dimers leads to CC-->TT transitions

The rate of UV-induced deamination of cytosine to uracil at a specific site in double-stranded (ds) DNA was monitored using a genetic reversion assay. M13mp2C141 ds DNA was exposed to 160 J/m2 UV (254 nm), incubated at 37 degrees C, pH 7.4, for various time intervals to allow for deamination, and treated with Escherichia coli photolyase in the presence of 365 nm light to reverse cyclobutane-type pyrimidine dimers. Upon transfection into uracil-glycosylase deficient (ung-) E. coli cells, the mutation (i.e., reversion) frequencies in the CCCC target sequence increased greatly with post-UV time of incubation at 37 degrees C, nearly doubling every day that the DNA had been held at 37 degrees C. After 8 days, the reversion frequencies had increased by two orders of magnitude upon transfection into ung- cells, relative to isogenic ung+ cells, indicating that most of the mutations arising in UV/photolyase-treated ds DNA were C-->T mutations mediated by a uracil intermediate. Sequencing of the revertants revealed that all mutations were single C-->T or tandem double CC-->TT mutations. An increasing percentage of tandem double CC-->TT mutations was found with longer post-UV incubation times, yet none occurred if the post-UV delay time step was omitted before photoreversal. After a 4-day delay between UV and photoreversal at 37 degrees C, greater than 84% of the total revertants had tandem double CC-->TT mutations. Thus, the generation of a tandem double mutation is a time-dependent process that arises in DNA after the initial UV exposure. The rate of appearance (with a pseudo-first-order rate constant ca. 10(-6) s-1) of tandem double mutations during incubation of UV-irradiated DNA is inconsistent with two random, independently occurring mutational events and suggests a concerted deamination of both residues in a tandem cytosine pyrimidine (C < > C) dimer. Considering that deamination in a C < > C dimer occurred here with a half-life of ca. 5 days, in contrast to the measured half-life of ca. 20,000 years for spontaneous (non-UV-treated) cytosine deamination for the same target, these studies show that the formation of pyrimidine dimers in DNA increases the rate of deamination by six orders of magnitude, leading to the accelerated formation of single C-->T and tandem double CC-->TT mutations.

[Effects of ding zhi pills on the scopolamine-induced impairment of passive avoidance in rats]

The Ding Zhi Pills described in "Thousand-Golden-Prescriptions" have better memory improving effect than those described in "Prescriptions People's Welfare Pharmacy". A combination of Poria, Radix Polygalae and Rhizoma Acori Graminei could enhance the pharmacologic effect of Radix Ginseng. Cinnabaris, described in "Prescriptions People's welfare Pharmacy", as one of the compositions in Ding Zhi Pills, does not improve the impairment of learning and memory, and therefore seems to have no meaning in the Ding Zhi Pills.

Potassium currents in cultured human pulmonary arterial smooth muscle cells

In this study, using whole cell and single-channel configurations of the patch-clamp technique, we characterized K+ currents (IK) in cultured human pulmonary arterial smooth muscle cells. The net whole cell outward membrane current (IKo) was activated at potentials positive to -60 mV. One component of IKo, IK(dr), was inhibited by 4-aminopyridine (4-AP) and high concentrations of tetraethylammonium (TEA) but was Ca2+ and charybdotoxin (CTX) insensitive. The other component of IKo, IK(Ca), was voltage and Ca2+ dependent and was inhibited by CTX and low concentrations of TEA. Activation of IKo in single-channel recordings was voltage dependent and demonstrated a high-conductance channel (245 +/- 2 pS) that was Ca2+ and CTX sensitive [IK(Ca)] and a low-conductance channel (109 +/- 2 pS) that was inhibited by 4-AP [IK(dr)] but was insensitive to low concentrations of TEA or to an increase in intracellular [Ca2+]. In isolated pulmonary arterial rings, TEA and 4-AP caused an additive increase in arterial tension. To our knowledge these data provide the first characterization of the IK in human pulmonary arterial smooth muscle cells and indicate that IK(Ca) and IK(dr) play an important role in maintaining pulmonary vascular tone. The data confirm previous observations in pulmonary smooth muscle cells of animal models.

Prenatal identification of i(Yp) by molecular cytogenetic analysis

An i(Yp) is a rare marker chromosome. We present a case of de novo 46,X,i(Yp) detected prenatally in an amniotic fluid specimen. Fluorescence in situ hybridization (FISH) studies using a panel of Y-specific biotinylated DNA probes identified the marker chromosome as i(Yp). Comparative genomic hybridization (CGH) studies further confirmed the diagnosis. Upon pregnancy termination, external examination of the fetus revealed a generally well-developed male fetus with slight facial dysmorphism and prominent rocker-bottom feet. The molecular cytogenetic data in this case proved very useful in genetic counselling and served as a good example illustrating the important role of molecular techniques for accurate identification of marker chromosomes.

Chorionic villi sampling: laboratory experience with 4,000 consecutive cases

Experience with 4,000 consecutive CVS cases shows that 1) the combination of both the direct and culture methods greatly reduces false diagnoses and maternal cell contamination; 2) the time interval between the sampling procedure and processing of villus specimens influences the quality of direct preparations; 3) maternal cell contamination (MCC) can be minimized with dissection of CVS specimens. We have compiled a large volume of confined placental mosaicism (CPM) cases to serve as a resource in interpreting mosaic cytogenetic findings. It was noted that, in up to 92% of the mosaic cases, the abnormal cell line was confined to the placenta. The frequency of true chromosomal mosaicism was 0.2%, and is not different from that for amniocentesis.

Design and clinical evaluation of impedance pulmonary arterial pressure measuring instrument with computer

Impedance pulmonary arterial pressure(PAP) measuring instrument with a microcomputer was designed and manufactured. It performs the functions of graphic analysis, logic judgment and mean pulmonary arterial pressure (PAP) measurement. Impedance information obtained by impedance PAP measuring instrument with a microcomputer was consistent with that by type HB-3COG apparatus. This new instrument has many advantages, such as reliability, saving of time and efforts as well as simplicity in operation.

[Effect of ligustrazine controlled release capsule on hemorrheology in patients with cor pulmonale]

Before and after oral administration of Ligustrazine controlled release capsule, changes of hemorrheology and TXA2/PGI2 were evaluated in 16 patients with advanced cor pulmonale. It was shown that the effects of decreasing whole blood and plasma viscosity and lowering hematocrit and fibrinogen level were noted after one course of treatment with this medication. It is suggests that anticoagulant, effect of Ligustrazine is probably related to its role of improving inbalance between TXA2 and PGI2 in patients with cor pulmonale.

Effects of sustained ligustrazine on hemorrheology in patients with chronic pulmonary heart disease

Before and after oral administration of sustained Ligustrazine, changes of hemorrheology and TXA2/PGI2 were evaluated in 16 patients with advanced chronic pulmonary heart disease. A decrease in whole blood and plasma viscosity, and reductions in hematocrit and fibrinogen were found after one course of treatment with sustained Ligustrazine. The mechanism of these effects may be related to improved modulation of imbalance of TXA2/PGI2 in patients with advanced chronic pulmonary heart disease.

[Effect of ligustrazine controlled release capsule on pulmonary hemodynamic and right ventricular systolic time intervals in patients with cor pulmonale]

Before and after oral administration of Ligustrazine controlled release capsule, pulmonary hemodynamic and right ventricular systolic time intervals, arterial blood gas and TXA2/PGI2 were studied. It was shown that decreasing of pulmonary arterial pressure and pulmonary vessel resistance, and heart rate, increasing of cardiac output, right ventricular systolic time intervals and arterial blood gas improving after one course of treatment with Ligustrazine controlled release capsule. It suggested that vasodilation caused by Ligustrazine is probably related to its vasodilating pulmonary vessela and improving imbalance between TXA2/PGI2 in patients with Cor Pulmonale.

Effects of ligustrazine controlled release capsule in chronic pulmonary heart disease

Before and after oral administration of ligustrazine controlled release capsule, pulmonary hemodynamics, right cardiac function, arterial blood gas and TXB2/6-keto-PGF1 alpha were studied in 16 patients with advanced cor pulmonale. The decrease of pulmonary arterial pressure and pulmonary vascular resistance, increase of cardiac output, improvement of right cardiac function and arterial blood gas were demonstrated after one course of treatment. The mechanism of these effects may be related to improvement of imbalance of TXB2/6-keto-PGF1 alpha. These results were in agreement with those of intravenous administration of ligustrazine, but no adverse reactions were found.

Selection of recombinant vaccinia viruses (Tian Tan strain) expressing hepatitis B virus surface antigen by using beta-galactosidase as a marker

We constructed a plasmid that contains a small piece of DNA with two vaccinia promoters running in opposite directions--a promoter from a late gene encoding an 11 K polypeptide (P11) and a promoter from an early gene encoding 25K (P25). These promoters were isolated from the Tian Tan strain of vaccinia virus and were flanked by the thymidine kinase (TK) sequence of the same virus. Genes encoding the hepatitis B virus surface antigen (HBsAg) and the Escherichia coli beta-galactosidase (LacZ) were inserted downstream of the 11 K and 25 K promoters respectively so that coexpression plasmids were constructed. Recombinant vaccinia viruses were selected directly by picking blue plaques formed under overlaying agarose medium containing X-gal. HBsAg was expressed to high level by these recombinant viruses. These recombinant viruses showed reduced virulence on rabbit skin and induced anti-HBs after intradermal inoculation of rabbits.

The acute effects of ligustrazini on hemodynamics and right cardiac function in pulmonary arterial hypertension secondary to chronic obstructive pulmonary disease

We studied 20 patients with pulmonary arterial hypertension secondary to chronic obstructive pulmonary disease (COPD) to investigate the acute effect of Ligustrazini on hemodynamics and right cardiac function. The results suggested that Ligustrazini had the effects of dilating pulmonary vessel, decreasing mean pulmonary arterial pressure and pulmonary vascular resistance, increasing cardiac output, and improving right cardiac function. The maximum effects of Ligustrazini occurred at 30 min after starting administration of the drug, but its effects disappeared 1 h after its withdrawal. From the above we are led to conclude that Ligustrazini as a vasodilator works rapidly, but its effects do not persist long.

[Evaluation of the immediate effect of ligustrazine in chronic cor pulmonale]

Twenty patients with chronic cor pulmonale were studied to assess the immediate effect of Ligustrazini on hemodynamic and right cardiac function. After intravenous administration of Ligustrazini at rest, there was statistically significant decrease in pulmonary arterial pressure, pulmonary vascular resistance and heart rate, increase in cardiac output and improvement in right cardiac function. Maximal effect was observed half an hour after treatment. But the effect disappeared after discontinuing the treatment of Ligustrazini for one hour. It is suggested that the effect of Ligustrazini appears early but does not last long.

Bethanechol supersensitivity test, rhabdosphincter electromyography and bulbocavernosus reflex latency in the diagnosis of neuropathic detrusor areflexia

A total of 57 patients with neuropathic or nonneuropathic detrusor areflexia was studied with the bethanechol supersensitivity test, electromyography of the urethral rhabdosphincter and bulbocavernosus reflex latency. The sensitivity of these tests in detecting neuropathic areflexia was 90, 87.5 and 78.1 per cent, respectively, and the specificity was 95.6, 76 and 80 per cent, respectively. When all 3 tests were performed together the combined accuracy approached 100 per cent. These combined tests are useful in the diagnosis of patients with equivocal bladder neuropathic conditions and in those with subtle neurological lesions.

Penile prosthesis surgery in the treatment of impotence in the immunosuppressed man

Thirteen male diabetic patients on immunosuppressive therapy following organ transplantation underwent implantation of 14 penile prostheses for treatment of organic impotence. Except for extended parenteral antibiotic therapy and increased steroid coverage postoperatively, the preoperative, perioperative and postoperative management in all 13 patients was similar to that of routine penile implantation procedures. No infections or erosion complications were encountered. We conclude that the penile prosthesis should be included in the armamentarium for the treatment of impotence in the immunosuppressed man.

Vesicoureteral reflux in children with myelodysplasia: natural history and results of treatment

A total of 58 children with myelodysplasia underwent radiographic and cystometric evaluation and were followed periodically for an average of 58 months. Of this group 30 (52 per cent) demonstrated vesicoureteral reflux, including 16 with low grade and 14 with high grade reflux. In 6 children low grade vesicoureteral reflux resolved with prophylactic antibacterials only, while decompressive treatment was required in 6, antireflux surgery was required in 2 and 2 were lost to followup. Despite adequate decompressive treatment 12 of the 14 children with high grade vesicoureteral reflux required an antireflux operation and 2 were lost to followup. Among those who underwent an operation there has been no recurrent reflux but 3 children have shown evidence of upper urinary tract deterioration. We describe our current approach to the treatment of vesicoureteral reflux in children with neurogenic bladder dysfunction and suggest a management protocol based on urodynamic findings.