Integrin-mediated activation of mitogen-activated protein kinase is independent of the activation of protein kinase C epsilon during the spreading of HeLa cells on a gelatin substratum

Spreading of HeLa cells on a gelatin substratum is initiated by the activation of protein kinase C epsilon (PKC epsilon) upon contact of the cells with the matrix. In this study, we examined the functional role of PKC epsilon in the activation of mitogen-activated protein kinase (MAP kinase) and its relationship to cell spreading. MAP kinase isoforms, Erk-1 and -2, are activated upon attachment of HeLa cells to gelatin. Inhibition of PKC with calphostin C blocked cell spreading without any effect on MAP kinase activation. In contrast, inhibition of MAP kinase kinase blocked adhesion-induced MAP kinase activation, but showed no effect on either translocation of PKC epsilon or cell spreading. Thus, activation of PKC epsilon that occurs upon HeLa cell attachment to gelatin is related to cell spreading but not to the activation of MAP kinase, and MAP kinase is activated upon HeLa cell attachment in the absence of cell spreading.

Endothelial alterations and senile calcific aortic stenosis: an electron microscopic observation

Calcific degeneration of aortic valves were investigated in 10 patients with senile calcific aortic stenosis by means of high resolution scanning electron microscopy (HR-SEM) and transmission electron microscopy (TEM). All the specimens obtained during aortic valve surgery HR-SEM and TEM examinations consistently showed various degrees of pathological alterations and calcification involving surface endothelium, underlying basement membranes and deeper layers of interweaving networks of collagen fiber bundles in the pars fibrosa of the valve tissues. Calcific deposits in the valve tissues always occurred in the vicinity of the endothelial defects and in the subendothelial structures just beneath the defective endothelium. The amount of calcific deposits in the valve tissues increased in proportion to the severity of endothelial damage and gradually decreased from the defective endothelial surface to the deeper layer of collagen tissue. In addition, apoptotic cell death, particularly of the fibrocytes in the valve tissue, was closely related to the severity of endothelial injury. Cellular fragments derived from the apoptotic cells were always associated with calcium deposits. Based on the above findings, our results provide evidence that the alteration of endothelial integrity plays a contributory role in calcific degeneration in the aortic valve leading to the development of senile calcific aortic stenosis.

Interaction between obesity and genetic polymorphisms in the apolipoprotein CIII gene and lipoprotein lipase gene on the risk of hypertriglyceridemia in Chinese

To understand the effects of the interaction between genetic polymorphisms and obesity on the risk of hypertriglyceridemia (HTG), two polymorphisms, an SstI polymorphism on the apolipoprotein CIII gene and a HindIII polymorphism on the lipoprotein lipase gene, were analyzed in 339 Chinese subjects with (82 cases in the HTG group) or without HTG (257 cases in the control group). Our data revealed that the frequencies of obesity, the SstI minor allele (S2), and the HindIII major allele (H+) in the HTG group were significantly higher than in the control group. Subgroup analysis revealed that the association between these two polymorphisms and HTG occurred predominantly in nonobese subjects and in subjects with the less hypertriglyceridemic genotype of another polymorphism. Multivariate logistic regression analysis showed that all three risk factors (obesity, S2-containing chromosome, and H+ homozygosity) were associated with HTG, and an interaction was found between obesity and H+ homozygosity for the occurrence of HTG. The risk of HTG increased significantly with combinations of risk factors. Subjects can be divided into low or high risk groups for HTG using such combinations. These results provide evidence of interaction between obesity and the HindIII polymorphism of the lipoprotein lipase gene on the risk of HTG.

Skeletal status of men with early and late ankylosing spondylitis

PURPOSE

To assess the influence of extent of disease on the skeletal status of men with ankylosing spondylitis (AS).

PATIENTS AND METHODS

Fourteen men with AS were studied at entry and again after 15 months. Bone mineral density (BMD) was assessed by single photon absorptiometry (SPA), dual energy x-ray absorptiometry (DXA), and quantitative computed tomography (QCT). Calciotropic hormones and bone turnover were also assessed, and biopsies of iliac crest and skin were taken after tetracycline double-labeling from 10 subjects. Clinical evaluation and Health Assessment Questionnaires were used to assess functional status.

RESULTS

Of the 14 participants, 7 had sacroiliitis alone without radiologic evidence of spinal involvement (early disease) and 7 had sacroiliitis with extensive vertebral calcifications and immobilization (late disease). QCT baseline lumbar spine BMD was very low in both groups compared with normative standards (Z score = -3.08 +/- 1.83, P < 0.0001) and did not change significantly over 15 months. This low BMD was more marked in late disease than in early disease subjects (P < 0.01). DXA BMD at the lumbar spine was lower than predicted in early disease subjects (Z score = -1.08 +/- 0.67, P = 0.005) but not in the late disease group. DXA BMD was also low at the all three hip sites (Z score = -0.96 +/- 0.86, P < 0.01). Significant differences between late disease group and normative values were apparent at all hip sites. Values in early disease subjects, however, did not differ from age-predicted norms. Bone mineral status did not change significantly over the 15-month period of observation. Circulating parathyroid hormone (PTH) and vitamin D metabolites were normal in both groups as were creatinine clearance and urinary excretion of calcium and hydroxyproline. Osteocalcin levels were normal in all but the two youngest subjects in the early disease group. Histomorphometry of the iliac crest showed no consistent change in bone turnover. Bone volume and trabecular width were low in many cases. Cancellous bone volume correlated with lumbar spine BMD by QCT (r = 0.69, P = 0.026) but not with DXA. Although beneficial changes occurred in exercise tolerance and pain over time, anthropometric measurements did not improve.

CONCLUSION

BMD is low in both the axial and peripheral skeleton in men with AS and is independent of spinal immobilization. Anterioposterior lumbar spine DXA in late AS is less useful than QCT in determining the degree of osteopenia in late AS. Bone mineral deficits in AS do not reflect measurable metabolic derangement or hypogonadism. Although bone histomorphometry suggests both trabecular thinning and loss of structural elements as mechanisms involved in low bone volume, the exact cause of osteopenia in AS remains to be determined.

Fibrin(ogen)-related antigens in rabbits experimentally infected with rabbit haemorrhagic disease virus

We investigated fibrin(ogen)-related antigens in liver tissues of rabbits infected with rabbit haemorrhagic disease (RHD) virus. Fibrin(ogen)-related antigens were detected in the sinusoids of liver at six hours post infection (pi). At 18 hours pi, the antigens were clearly detected in the hepatocytes infiltrated with heterophils rather than in the sinusoid. In the rabbits that spontaneously died (30 hours pi), fibrin(ogen)-related antigens were detected in both degenerating and some intact hepatocytes. They were also expressed in the necrotic foci of hepatocytes infiltrated by heterophils. By immunoprecipitation fibrin(ogen)-related antigens were extracted from the infected liver homogenates and analysed by sodium dodecyl sulphate polyacrylamide gel electrophoresis and Western blot analysis. There was an increase in fibrinogen and A alpha polypeptide chains in the liver homogenates from rabbits sacrificed at 18 and 24 hours pi, including those that died. Disseminated intravascular coagulation developed after progress of degeneration and necrosis of hepatocytes in RHD. It is assumed that the resultant consumption of fibrinogen triggers replenishment of fibrinogen by hepatocytes.

Angiotensinogen and angiotensin-I converting enzyme gene polymorphisms and the risk of coronary artery disease in Chinese

The homozygous deletion allele (DD) of the angiotensin-I converting enzyme (ACE) gene and the T235 homozygote of the angiotensinogen (AGT) gene have been reported to be correlated with an increased prevalence of coronary artery disease (CAD) and myocardial infarction (MI). The importance of the DD genotype and T235 homozygote as genetic risk factors for CAD in Chinese remains uncertain. This study included 426 patients who underwent coronary angiography and 180 healthy subjects without clinical evidence of CAD. Coronary angiography identified 268 patients with CAD (CAD group) and 158 patients without CAD. The healthy subjects and patients without angiographic evidence of CAD constituted the control group. Three polymorphisms were studied: an insertion/deletion (I/D) polymorphism of the ACE gene and the T174 M and M235T polymorphisms of the AGT gene. No association was found between any of the three studied polymorphisms and the risk of CAD or MI in Chinese using univariate or multivariate analysis. In multivariate analysis, the relative risks were 1.20 (95% confidence interval = 0.91-1.61, P = 0.20) for the DD genotype, 1.05 (95% CI = 0.82-1.35, P = 0.69) for the T174 homozygote, and 1.19 (95% CI = 0.91-1.55, P = 0.20) for the T235 homozygote. Similarly, no significant difference was found in the frequencies of the DD genotype and the T174 and T235 homozygotes between the control group, the CAD group, the non-MI group, and the MI group when analyzed according to sex, age, or degree of risk. Our data suggest that neither the DD genotype of the ACE I/D polymorphism nor the T174 and T235 homozygotes of the AGT gene confer significant risk for CAD or MI in Chinese.

Detection of nucleic acids of porcine reproductive and respiratory syndrome virus in the lungs of naturally infected piglets as determined by in-situ hybridization

Replication of porcine reproductive and respiratory syndrome virus (PRRSV) was studied in formalin-fixed paraffin wax-embedded lung tissues from seven naturally infected piglets by in-situ hybridization with a non-radioactive digoxigenin-labelled probe. A 433 base pair cDNA probe for the viral RNA encoding the nucleocapsid proteins of a Korean PRRSV isolate was generated by the polymerase chain reaction. All seven piglets infected with PRRSV showed a distinct, positive signal, scattered throughout the alveolar septa and spaces. Positive cells typically exhibited dark brown staining deposits in the cytoplasm without background staining. In-situ hybridization demonstrated that PRRSV replicated primarily in interstitial and alveolar macrophages, and occasionally in type 2 pneumocytes. The bronchial or bronchiolar epithelium did not exhibit a hybridization signal for PRRSV nucleic acids. The anterior and middle lobes of the lung were more reliable than the caudal or accessory lobes for the detection of PRRSV nucleic acids. The in-situ hybridization technique used was rapid, specific and sensitive, and may prove useful for the diagnosis of PRRSV infection in routinely fixed and processed tissues.

Substrate transport and cocaine binding of human dopamine transporter is reduced by substitution of carboxyl tail with that of bovine dopamine transporter

A chimeric dopamine transporter (DAT) cDNA encoding mutant human DAT (hDAT) protein in which the intracellular carboxyl-terminal tail is replaced by that of the bovine dopamine transporter (bDAT) was constructed. The chimeric hDAT cDNA was expressed in COS-7 cells, and [3H]dopamine and [3H]MPP+ uptake and [3H]CFT binding capacities were assessed. Substrate transport and ligand binding of bDAT were reduced by 32-43% as a result of substitution of the carboxyl tail in hDAT, suggesting that the functional characteristics of bDAT arise from differences in the carboxyl tail between human and bovine DAT. Thus, it appears that the sequences encoded within the carboxyl terminal of DAT would be one of the important determinants for its functions.

Thrombectomy for left ventricular protruding thrombi in a patient with dilated cardiomyopathy

Left ventricular thrombus is one source of cardiogenic embolism. The protruding, mobile type is the highest risk subgroup but is rarely encountered. Thrombectomy is one choice of therapy, and variously recommended based primarily on the experience with myocardial infarction. We report a rare case of successful left ventricular thrombectomy for two protruding, mobile thrombi in a patient with idiopathic dilated cardiomyopathy in order to prevent repeat embolization.

Continuous antegrade warm blood cardioplegia attenuates augmented coronary endothelium-dependent contraction after cardiac global ischemia and reperfusion

BACKGROUND

Experiments were designed to evaluate the effect of warm blood cardioplegia on endothelium-dependent contraction of the coronary endothelium after cardiac global ischemia and reperfusion.

METHOD

Dogs (n = 12 in each group) were exposed to extracorporeal circulation with the body temperature at 37 degrees C (group 1) or 28 degrees C (groups 2 and 3). The ascending aorta was crossclamped for 120 minutes while continuous infusion of warm blood cardioplegec solution (group 1) or intermittent infusion of cold (4 degrees C) crystalloid cardioplegic solution (group 2) was performed via the coronary arteries through the aortic root. Cardioplegic solution was not used in group 3 animals. The heart was then allowed to function for 60 minutes of reperfusion. Reperfused (groups 1, 2, and 3) and control (group 4) coronary arteries were then harvested for study.

RESULTS

Perfusate hypoxia caused endothelium-dependent contraction in the arteries of all four groups that could be attenuated by NG-monomethyl-L-arginine (L-NMMA) or L-NMMA plus D-arginine, but not by L-NMMA plus L-arginine or endothelin receptor A and B antagonist PD 145065. The endothelium-dependent contraction results in groups 2 and 3 (75% +/- 4% and 80% +/- 5%, respectively) were significantly greater than those in groups 1 and 4 (15% +/- 3% and 18% +/- 5%, respectively). Scanning electron microscope studies showed that platelet adhesion and aggregation, areas of microthrombi, disruption of endothelial cells, and separation of the intercellular junction could be found in coronary segments from groups 2 and 3, but not in vessels from groups 1 and 4.

CONCLUSION

These experiments suggest that global ischemia and reperfusion enhances hypoxia-mediated endothelium-dependent contraction of the coronary endothelium and damages the ultrastructure. These kinds of changes can be prevented by continuous antegrade infusion of warm blood cardioplegic solution during global ischemia.

Telomerase activity and its clinicopathological significance in gastric cancer

In order to assess the role of telomerase in development of malignant gastric cancer, we measured the telomerase activity in gastric cancer tissues and normal tissues obtained from 95 patients by employing recently developed sensitive PCR (polymerase chain reaction)-based telomerase assay (telomeric repeat amplification protocol, TRAP). We also investigated how telomerase activity related to other clinicopathological findings including DNA ploidy and K-RAS gene point mutation. The telomerase activity was present in 85 of the 95 gastric cancer tissues, whereas we detected no telomerase activity in any normal tissue. The incidence of telomerase activity in gastric cancer tissues was not correlated to age, sex, tumour stage, histological grade, DNA ploidy or K-RAS mutation. Disease-free or overall survival of patients having tumours with detectable telomerase activity was not significantly different from that of those without telomerase activity. These findings suggest that telomerase may play a key role in the establishment and progression of the gastric cancer and further studies will be needed to elucidate the biological role of telomerase in gastric cancer.

Rhabdomyolysis, acute renal failure and hepatopathy induced by lovastatin monotherapy

Lovastatin is a popular drug for the treatment of hypercholesterolemia. Few serious complications are associated with its use although rhabdomyolysis with renal failure has been reported when lovastatin is combined with cyclosporine or other drugs following transplantation. We report the case of a patient who developed hepatopathy and rhabdomyolysis accompanied by acute renal failure after 4 weeks of lovastatin monotherapy. The pathogenesis and treatment of these complications are also discussed.

Additive effects of diltiazem and lisinopril in the treatment of elderly patients with mild-to-moderate hypertension

A multicenter, double-blind, placebo-controlled trial with multifactorial design was conducted to evaluate the safety and efficacy of the calcium-channel blocker diltiazem, in a sustained release preparation, and the angiotensin converting enzyme inhibitor, lisinopril, in the treatment of elderly Chinese patients with mild-to-moderate hypertension. In addition to the hypotensive effects of combinations of both drugs compared with monotherapy, all given once daily, the effect on quality of life was also evaluated. This study consisted of a 3 x 2 multifactorial design in which 156 women and men with a sitting diastolic pressure of between 95 mm Hg and 114 mm Hg, after a 4-week placebo washout phase, were randomized to one of six treatment groups for 12 weeks of active treatment. Monotherapy with diltiazem 120 or 240 mg produced increasing reductions of systolic and diastolic blood pressure. Compared with placebo, lisinopril 10 mg had an effect intermediate between the diltiazem doses. The combinations of diltiazem 240 mg + lisinopril 10 mg and diltiazem 120 mg + lisinopril 10 mg showed increased efficacy in reducing systolic and diastolic blood pressure compared to these drug doses used in monotherapy, but the effect of the combinations was less than predicted by an additive model. Although the total number of other adverse events reported was similar for all active treatment groups compared to placebo, lisinopril-induced cough was common with an incidence of 31% after rechallenge. Premature drug withdrawal was necessary in four of 78 patients receiving lisinopril, due to intractable cough. The combination of diltiazem 240 mg and lisinopril 10 mg was significantly more effective at reducing blood pressure than either drug alone; this additive effect did not result in a higher rate of adverse effects or impairment of quality of life. Thus, combination therapy with these agents was well tolerated and resulted in increased efficacy in these elderly patients.

Fourth-harmonic generation at a crystalline GaAs(001) surface

We demonstrate fourth-harmonic generation from a GaAs(001) surface by using femtosecond pulses well below damage threshold. Our data reveal a strong fourfold anisotropic surface-specific polarization that is not present in second-harmonic generation and is nearly as strong as the bulk polarization.

Novel pattern of DNA methylation in Neurospora crassa transgenic for the foreign gene hph

It has previously been reported that multiple copies of the hph gene integrated into the genome of Neurospora crassa are methylated at Hpa II sites (CCGG) during the vegetative life cycle of the fungus, while hph genes integrated as single copies are not methylated. Furthermore, methylation is correlated with silencing of the gene. We report here the methylation state of cytosine residues of the major part of the promoter region of the hph gene integrated into the genome of the multiple copy strain HTA5.7 during the vegetative stage of the life cycle. Cytosine methylation is sequence dependent, but the sequence specificity is complex and is different from the sequence specificity known for mammals and plants (CpG and CpNpG). The pattern of DNA methylation reported here is very different from that measured after meiosis in Neurospora or in Ascobulus . After the sexual cycle in those two fungi all the cytosines of multiple stretches of DNA are heavily methylated. This indicates that the still unknown methyltransferase in Neurospora has a different specificity in the sexual and the vegetative stages of the life cycle or that there are different methyltransferases. The pattern of methylation reported here is also different from the pattern of cytosine methylation of transgenes of Petunia , the only pattern published until now in plants that has DNA methylation at cytosines which are not in the canonical sequences CpG and CpNpG.

Sequence variation of mitochondrial DNA control region in Koreans

The sequencing data for two mtDNA segments in control region I and II, 385 and 341 nucleotides long, respectively, for 306 unrelated Koreans are presented. In regions I and II, 139 and 58 polymorphic sites, respectively, were noted. These were distributed evenly along the control region, though the frequency of each site was variable. Nucleotide substitution rather than insertion/deletion was the prevalent pattern of variation. A total of 265 different mtDNA lineages in region I and 154 in region II were revealed. This result represents a substantial level of polymorphism in a defined population, and presents the possibility that mtDNA polymorphism could be used as an individual identification marker, especially when nuclear DNA is not available. In view of the complex pattern of variation, meticulous test-sequencing is thought to be more appropriate than RFLP analysis using restriction endonuclease or hybridization using an SSO probe. Racial differences with genealogical usage are also described.

Short-term safety and efficacy of low-dose simvastatin in elderly patients with hypertensive hypercholesterolemia and fasting hyperinsulinemia

To evaluate the short-term safety and efficacy of low-dose (10 mg) simvastatin in hypercholesterolemic, hypertensive elderly Chinese patients receiving antihypertensive treatment, a randomized, double-blind, placebo-controlled, 3-month trial was conducted. The patients had a total plasma cholesterol level of at least 250 mg/dL and had been, for at least 3 months, consuming a standard lipid-lowering diet (American Heart Association Step 1 Diet). Elderly hypertensive patients (n = 76) were randomized to receive treatment with either placebo (n = 38) or simvastatin (n = 38). The dosage consisted of 10 mg simvastatin daily during the 3-month trial. During that period, in the simvastatin group, plasma levels of total cholesterol and low-density lipoprotein cholesterol decreased significantly (27% and 33%, respectively) compared with those levels in plasma in the placebo group. The plasma levels of high-density lipoprotein cholesterol increased (7%), whereas triglyceride levels slightly decreased (8%). There were no serious side effects, and simvastatin was generally well tolerated. Fasting hyperinsulinemia also improved (-21%) after 3 months of simvastatin therapy. Results of this study confirmed that a low dose (10 mg) of simvastatin daily is a safe and effective method of reducing plasma levels of total and low-density lipoprotein cholesterol in hypercholesterolemic, hypertensive elderly patients receiving concurrent antihypertensive drug therapy, and that it has the additional potential benefit of reducing plasma levels of insulin.

Neuroleptic drugs alter the dopamine transporter-mediated uptake and release of dopamine: a possible mechanism for drug-induced tardive dyskinesia

A bovine dopamine transporter (bDAT) cDNA was transfected into CV-1 cells, a cell line that lacks vesicular storage and release mechanisms. Using this cell line, the effects of neuroleptic drugs on DAT-mediated uptake and release of dopamine (DA) were examined. All of the neuroleptic drugs tested, inhibited DA uptakes in DAT expressing cells, and most of them were shown to promote spontaneous release of DA at the same time. These results imply that neuroleptic drugs would cause an overflow of DA in the synaptic cleft of extrapyramidal dopaminergic neurons, which could be one of the possible mechanisms of drug-induced tardive dyskinesia.

Expression of envelope protein (E2) of bovine viral diarrhea virus in insect cells

The gene encoding the envelope glycoprotein (E2) of bovine viral diarrhea virus (BVDV) was expressed in a baculovirus. The expressed protein was detected on the surface of infected cells by immunofluorescence. Western blotting analysis showed the presence of the expressed protein of a similar molecular size to the E2 protein. The antigenicity of expressed protein were tested in guinea pigs and cattle. The immunized animals developed neutralizing antibodies against BVDV.

Enhancing effects of phenobarbital and 3-methylcholanthrene on GST-P-positive liver cell foci development in a new medium-term rat liver bioassay using D-galactosamine

The carcinogenic potential of phenobarbital (PB) and 3-methylcholanthrene (3-MC) was assayed in a new medium-term carcinogenicity bioassay using D-galactosamine (DGA) as a nonsurgical method to induce liver cell regeneration in place of partial hepatectomy (PH). Rats were initially given a single ip injection (200 mg/kg) of diethylnitrosamine (DEN) and after 2 wk on basal diet received 2 ip injections of DGA (300 mg/kg) at the end of wk 2 and 5. They were treated with one of the test compounds PB or 3-MC in the diet or fed basal diet for wk 3-8 Carcinogenic potential was assessed by comparing the numbers and areas per square centimeter of glutathione S-transferase placental form-positive (GST-P+) foci in the livers of test chemical-treated animals with those of the control animals given DEN/DGA alone. Positive estimations of carcinogenicity were obtained for PB, which is a nongenotoxic liver tumor promoter, and for 3-MC, which is a genotoxic nonliver carcinogen. Increases of liver/body weight ratios and serum total cholesterol were observed in rats treated with PB or 3-MC. Interestingly, interlobe differences were found on the development of GST-P+ liver cell foci. Our results thus confirm that the present bioassay protocol with repeated administration of DGA instead of PH may offer a new and sensitive method to screen large-numbers of environmental liver and nonliver carcinogens.

Light-induced fluorescence spectroscopy to differentiate benign and malignant uterine cervical lesions

In Taiwan, cervical cancer is the leading malignancy among women. For the early detection of cervical neoplasia, light-induced fluorescence spectroscopy was conducted ex vivo to assess the ability of this technique to differentiate cervical neoplastic tissue (20 samples) from normal or inflammatory cervical tissue (37 samples) at an excitation wavelength of 280 nm. The principal fluorescent peaks occurred within +/- 5 nm of 330 nm and 470 nm emission. At 330 nm emission, the spectrum of the normal or inflammatory tissue was significantly stronger than that of the neoplastic tissue after are normalization. However, at 470 nm emission, the spectrum of the normal or inflammatory tissue was significantly weaker than that of the neoplastic tissue. A diagnostic algorithm based on the ratio of relative intensities of 330 nm to 470 nm emission within the 5 +/- nm peak area of each sample was calculated and paired. The ratios showed that histologically neoplastic lesions could be distinguished from inflammatory samples using a 280-nm-excitation wavelength with a sensitivity, specificity and positive predictive value of 94%, 82% and 73%, respectively. The average ratio of malignant or dysplastic cervical samples was significantly greater than that of the inflammatory samples (p < 0.001). Our ex vivo study indicated that light-induced fluorescence spectroscopy may be useful in differentiating malignant or premalignant from normal or inflammatory cervical tissue.

Efficacy of intracytoplasmic sperm injection (ICSI) treatment in the immunological infertile patients

PROBLEM

To evaluate the efficacy of intracytoplasmic sperm injection (ICSI) treatment in the immunological infertile patients.

METHODS

The subjects were 60 cycles of 44 immunological infertile patients and these clinical data were analysed, retrospectively. They were classified into female and male immunological infertility group and were treated with conventional IVF, ICSI, and half-ICSI.

RESULTS

The fertilization rate of ICSI (60.3%) and half-ICSI (60.7%) cycles were significantly (P < 0.01) higher than conventional IVF (42.6%) cycles. In the male immunological infertility group, fertilization rate was significantly (P < 0.01) higher in ICSI (60.7%) and half-ICSI (66.7%) cycles than in conventional IVF (27.4%) cycles and clinical pregnancy rate was higher in ICSI (54.5%) and half ICSI (33.3%) than in conventional IVF (25.0%) cycles.

CONCLUSIONS

We suggest that ICSI treatment is highly effective method to improve fertilization and pregnancy rate in IVF-ET program of male immunological infertility.

Induction of apoptotic cell death in a neuroblastoma cell line by dibucaine

Dibucaine, a local anesthetic known to interact with cell membranes, induced apoptosis in SK-N-MC human neuroblastoma cells in a dose-dependent manner. Apoptosis was demonstrated by direct visualization of morphological nuclear changes using a DAPI staining technique and confirmed by the production of characteristic ladder patterns of DNA fragmentation on gel electrophoresis. At concentrations which induced apoptosis, dibucaine significantly altered membrane fluidity, indicating that fluidity may be a major target for the cytotoxic action of dibucaine. Also, dibucaine increased intracellular calcium levels more effectively in calcium-containing Krebs-Ringer buffer than in calcium-free Krebs-Ringer buffer. Removal of extracellular calcium or addition of antioxidants or protein synthesis inhibitor effectively blocked dibucaine-induced apoptosis. These results suggest that membrane damage, intracellular calcium levels, and oxygen free radicals may be involved in the apoptosis induced by dibucaine.

Impaired endothelium-dependent relaxation after cardiac global ischemia and reperfusion: role of warm blood cardioplegia

OBJECTIVES

Experiments were designed to determine whether coronary endothelial dysfunction after cardiac global ischemia and reperfusion could be prevented by warm blood cardioplegic solution.

BACKGROUND

The coronary endothelium produces endothelium-derived relaxing factor (EDRF) to prevent vasospasm and thrombosis. After ischemia and reperfusion, endothelium-dependent relaxation (EDR) is diminished as a result of G-protein dysfunction.

METHODS

Dogs were exposed to extracorporeal circulation in 37 degrees C (group 1) or 28 degrees C (groups 2 and 3). The heart was ischemic for 120 min while continuous warm blood cardioplegic solution (group 1) or intermittent cold (4 degrees C) crystalloid cardioplegic solution was not used in group 3 animals. The heart was then allowed to function for 60 min of reperfusion.

RESULTS

Endothelium-derived relaxation in response to acetylcholine, adenosine diphosphate and sodium fluoride of the coronary rings of group 1 was significantly different from that of groups 2 and 3 but was not significantly different from that of group 4. In contrast, EDR in response to the receptor-independent calcium ionophore agonist A23187 was not significantly different between the four groups. Scanning electron microscopic studies showed that platelet adhesion and aggregation, area of microthrombi, disruption of endothelial cells and separation of the intercellular junction could be found in coronary segments of groups 2 and 3 but not in vessels of groups 1 and 4.

CONCLUSIONS

These experiments suggest that cardiac global ischemia and reperfusion impair receptor-mediated release of EDRF from the coronary endothelium with G-protein dysfunction. This type of coronary endothelial dysfunction can be prevented by continuous anterograde infusion of warm blood cardioplegic solution during global ischemia.