Magnesium sulphate and perinatal mortality and morbidity in very-low-birthweight infants born between 24 and 32 weeks of gestation in Japan.

OBJECTIVE: Maternal exposure to magnesium sulphate has a neuroprotective effect in premature infants. This study aimed to examine this neuroprotective effect and the dose-response relationship in very-low-birthweight infants born between 24 and 32 weeks of gestation. STUDY DESIGN: A retrospective cohort study compared the rates of mortality and brain damage between three groups: no magnesium sulphate, low-dose (<50g) magnesium sulphate and high-dose (≥50g) magnesium sulphate. RESULTS: Japanese maternal and neonatal databases were linked using six key parameters from 2003 to 2007. Of 298,514 deliveries, 9101 were very-low-birthweight infants. Among these, full matching was possible for 5562 infants. Of the fully-matched infants, 3763 were born between 24 and 32 weeks of gestation, and 1813 (48%) were followed-up beyond 18 months. A multivariate analysis of the data, including gestational age, sex, fetal growth restriction, antenatal steroids and low pH (<7.1), showed that the low-dose group had no beneficial effects in terms of a reduction in mortality or incidence of brain damage (cerebral palsy or mental retardation). The high-dose group showed a significantly higher mortality rate [odds ratio (OR) 1.9, 95% confidence interval (CI) 1.2-2.9]. A stratified subgroup analysis of infants born between 28 and 32 weeks of gestation showed that survivors in the low-dose group had significantly lower rates of cerebral palsy (OR 0.4, 95% CI 0.2-0.98) and brain damage (OR 0.2, 95% CI 0.1-0.9), while the high-dose group did not show any significant changes. CONCLUSION: This study found that antepartum exposure to magnesium sulphate did not reduce the infant mortality rate or influence neurological outcomes. However, among infants born between 28 and 32 weeks of gestation, rates of cerebral palsy and brain damage were found to be significantly lower among survivors in the low-dose group.

Self-trapping of strong electromagnetic beams in relativistic plasmas.

Interaction of an intense electromagnetic (em) beam with a relativistic electron-positron (e-p) plasma is investigated. It is shown that the thermal pressure brings about a fundamental change in the dynamics-localized, high amplitude, em field structures, not accessible to a cold (but relativistic) plasma, can now be formed under well-defined conditions. The possibilities of trapping em beams in self-guiding regimes to form stable two-dimensional solitonic structures in a pure e-p plasma are worked out.

Role of endothelium in regulation of smooth muscle membrane potential and tone in the rabbit middle cerebral artery.

1. The characteristic features of the endothelium-mediated regulation of the electrical and mechanical activity of the smooth muscle cells of cerebral arteries were studied by measuring membrane potential and isometric force in endothelium-intact and -denuded strips taken from the rabbit middle cerebral artery (MCA). 2. In endothelium-intact strips, histamine (His, 3-10 microM) and high K+ (20-80 mM) concentration-dependently produced a transient contraction followed by a sustained contraction. Noradrenaline (10 microM), 5-hydroxytryptamine (10 microM) and 9,11-epithio-11, 12-methano-thromboxane A2 (10 nM) each produced only a small contraction (less than 5% of the maximum K+-induced contraction). 3. N(G)-nitro-L-arginine (L-NOARG, 100 microM), but not indomethacin (10 microM), greatly enhanced the phasic and the tonic contractions induced by His (1-10 microM) in endothelium-intact, but not in endothelium-denuded strips, suggesting that spontaneous or basal release of nitric oxide (NO) from endothelial cells potently attenuates the His-induced contractions. Acetylcholine (ACh, 0.3-3 microM) caused concentration-dependent relaxation (maximum relaxation by 89.7 +/- 7.5%, n=4, P<0.05) when applied to endothelium-intact strips precontracted with His. L-NOARG had little effect on this ACh-induced relaxation (n=4; P<0.05). Apamin (0.1 microM), but not glibenclamide (3 microM), abolished the relaxation induced by ACh (0.3-3 microM) in L-NOARG-treated strips (n=4, P<0.05). 4. In endothelium-intact tissues, His (3 microM) depolarized the smooth muscle membrane potential (by 4.4 +/- 1.8 mV, n = 12, P < 0.05) whereas ACh (3 microM) caused membrane hyperpolarization (-20.9 +/- 3.0 mV, n = 25, P< 0.05). The ACh-induced membrane hypepolarization persisted after application of L-NOARG (-23.5 +/- 5.9 mV, n=8, P<0.05) or glibenclamide (-20.6 +/- 5.4 mV, n=5, P<0.05) but was greatly diminished by apamin (reduced to - 5.8 +/- 3.2 mV, n = 3, P< 0.05). 5. Sodium nitroprusside (0.1-10 microM) did not hyperpolarize the smooth muscle cell membrane potential (0.2 +/- 0.3 mV, n=4, P>0.05) but it greatly attenuated the His-induced contraction in endothelium-denuded strips (n-4, P<0.05). 6. These results suggest that, under the present experimental conditions: (i) spontaneous or basal release of NO from endothelial cells exerts a significant negative effect on agonist-induced contractions in rabbit MCA, and (ii) ACh primarily activates the release of endothelium-derived hyperpolarizing factor (EDHF) in rabbit MCA.

Effects of polyvalent alcohol solutions as dentine primers.

OBJECTIVES: The purpose of this study was to examine the bonding effect of polyvalent alcohols as dentine primers without a methacrylate group, which may cause contact dermatitis. METHODS: The efficacy of polyvalent alcohols as dentine primers was estimated by measuring the wall-to-wall polymerization contraction gap width of a light-activated resin composite filled in a cylindrical dentine cavity in an extracted human tooth. A dentine cavity was cleaned with ethylenediaminetetraacetic acid (EDTA) and primed with an aqueous solution of either ethylene glycol, glycerol, erythritol, xylitol or sorbitol at concentrations of between 25 and 75 wt%. A light-cured resin composite was filled after the application of a commercial dual-cured bonding agent. RESULTS: Contraction gap formation was completely prevented only in the group in which the dentine cavity had been primed with an aqueous solution of 62.5% wt% ethylene glycol. Furthermore, in the measurement of a tensile bond strength to a flat dentine surface, high tensile bond strength (17.5 +/- 4.4 MPa) was observed in the group that was primed with 62.5% ethylene glycol solution. CONCLUSION: These results suggest that it is not necessary to dissolve methacrylates in a dentine primer when the primer is dried with a blast of compressed air before application of a polymerizable, suitable bonding agent. It is concluded that a dentine primer composed of polyvalent alcohol solutions without a methacrylate group which may cause contact dermatitis, is effective as a dentine primer, affects the dentine surface, and promotes the efficacy of the dentine bonding system.

Duration of cleaning and priming of dentine and contraction gap formation.

OBJECTIVES: The effects of the duration of cleaning and priming on the marginal adaptation of a light-activated resin composite in a cylindrical dentine cavity were examined by measuring the width of the wall-to-wall polymerization contraction gap. METHODS: The dentine cavity was cleaned with ethylene diamine tetra-acetic acid (EDTA) and primed 35 vol% hydroxyethyl methacrylate (HEMA) or glyceryl methacrylate (GM) solution for up to 60 s. The cavity was filled with a light-cured resin composite after the application of a dual-cured dentine bonding agent. RESULTS: The formation of a contraction gap by the composite appeared to be prevented completely, regardless of the duration of priming with GM solution, when the cavity was cleaned with EDTA for 60 s. When cleaning was limited to just 30 s, GM priming had to be prolonged to 60 s to obtain complete marginal integrity. A significantly wide contraction gap was observed without EDTA cleaning, even when the cavity wall was primed with GM solution for 60 s. CONCLUSION: GM solution was a better dentine primer than HEMA solution, since HEMA priming did not prevent gap formation under any of the conditions tested.

[Emergency coronary artery bypass grafting with warm blood cardioplegia for a patient with acute myocardial infarction and severe left ventricular dysfunction].

Emergency coronary artery bypass grafting was performed in a 61 year old man who developed acute severe cardiac and respiratory dysfunction after myocardial infarction. At operation cardiac arrest was obtained by warm blood cardioplegia in antegrade intermittent fashion. The left anterior descending artery, diagonal branch, and right coronary artery were revascularized by saphenous vein (SVG). After declamping the aorta, spontaneous heart beating was obtained and postoperative course was uneventful. Postoperative examination showed patent all SVGs and improved cardiac function. Although the delivery of the warm blood cardioplegia was controversial, our recent study revealed that the intermittent antegrade delivery of warm blood cardioplegia showed no ischemic changes of the heart during the procedure.

[A case of discrete type of subpulmonary stenosis].

We reported a 8-year-old girl having discrete type of subpulmonary stenosis. This patient was associated with atrial septal defect (ASD), valvular pulmonary stenosis, and persistent left superior vena cava (PLSVC). The incidence of this type of subpulmonary stenosis is less frequent than that of subaortic lesion. ASD was closed by the autologous pericardium and a transannular patch was used for enlargement of the right ventricular outflow tract followed by commissurotomy of the pulmonary valve and resection of subpulmonary discrete lesion. She was uneventful and postoperative pulsed doppler echocardiogram showed good results.

Reconstruction of the skull base using a silicone plate during transsphenoidal surgery.

Our operative experience of reconstruction of the skull base using a silicone plate during rhinoseptoplastic transsphenoidal surgery is described. A suitably shaped plate can be easily and quickly made from a large silicone block of the type that is widely used in cosmetic surgery. The plates can be distinguished on magnetic resonance images postoperatively. We consider that this technique is of use not only for repairing the sellar floor, but also for closing a wide defect of the skull base.

[Detection of African type penicillinase-producing Neisseria gonorrhoeae in Japan].

The Plasmid DNA patterns of 22 penicillinase-producing Neisseria gonorrhoeae (PPNG) strains isolated from male patients with gonococcal urethritis in 1988 at Tokyo Metropolitan Taito Hospital were determined. The 3.3 megadalton plasmid, the so called the African type plasmid, was present in 3 isolates out of 22 PPNGs, all of which occurred with a conjugative 24.5 megadalton plasmid. 4.4 megadalton plasmid was present in 19 isolates out of 22 PPNGs, 5 of which occurred with a conjugative 24.5 megadalton plasmid. The infective sources of the 3 cases of the African type PPNGs were found as 1 from philippines and 2 from prostitutes, so called Soap Land Girl in Japan. And they suggests that the African type PPNGs are already common in Japan.

Activities of dipeptidyl peptidase II and dipeptidyl peptidase IV in mice with lupus erythematosus-like syndrome and in patients with lupus erythematosus and rheumatoid arthritis.

We examined the activities of peptidases in plasma and tissues of the New Zealand Black (NZB) mouse as an animal model of human systemic lupus erythematosus, and also in serum from patients with rheumatoid arthritis and systemic lupus erythematosus. Activities of dipeptidyl peptidase II (DAP II) and post-proline cleaving enzyme (PPCE) were increased, and dipeptidyl peptidase IV (DAP IV) activity was decreased in plasma and spleen of NZB mice, as compared with the control BALB/c mice. Likewise, the activity of DAP II was increased and that of DAP IV was decreased in serum of patients with rheumatoid arthritis and systemic lupus erythematosus. These results indicate the importance of hydrolytic enzymes in the pathogenesis of autoimmune diseases.

Cases with familiar amyloid neuropathy starting of the upper limbs and having hepatic disorder.

Here we are reporting two cases consisting of a male patient and his elder sister from Kagashima in Gifu City and both suffering from polyneuropathy of dissociation type and skin amyloidosis. In the former, the presence of amyloid was demonstrated not only in the skin, but also in the stomach, liver and gums. He was also diagnosed suffering from chronic hepatitis of inactive type. He responded to DMSO and Cepharanthin. In the patients, no urinary Bence Jones protein nor blood M component was detected and the amyloid exhibited resistance to potassium permanganate treatment. The neuropathy of the patients were slightly different from that of the Portuguese type which starts on lower extremities as well as those conventionally have been reported in Japan.

[Distribution pattern of fibronectin in human lung cancer tissue].

The distribution pattern of fibronectin in human lung cancer tissues has been studied using the indirect immunoperoxidase technique. In adenocarcinoma fibronectin is observed in the basal side of cancer cells and tumor stroma. In squamous cell carcinoma, it is seen in the basal side of cancer cells, surface of cancer cells and tumor stroma. The difference between adenocarcinoma and squamous cell carcinoma in invasion and metastasis was investigated to have some relation to the distribution pattern of fibronectin.