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A comparison is presented on picophytoplankton populations in the equatorial upwelling and the western warm pool of the Pacific Ocean. The low-chlorophyll/high-nutrient conditions of the upwelling encouraged all groups of picophytoplankton except Prochlorococcus, while the western warm pool showed higher populations of Prochlorococcus and significantly lower populations of other picophytoplankton.

Clobazam is a benzodiazepine with anti-anxiety and anticonvulsant properties marketed in several countries. Norclobazam, a metabolite of clobazam, has similar pharmacological activity but weaker sedative and tranquilizing effect. The two drugs were detected by GC-MS and determined by HPLC-DAD in the samples from a postmortem case. The femoral blood concentrations of clobazam and norclobazam were 0.72 and 36 μg/mL, respectively. The concentration of the active norclobazam was very high. The sum of both clobazam and norclobazam blood concentration (36.72 μg/mL) was clearly toxic, but was not necessarily fatal. Other associated drugs concentrations were within their therapeutic ranges. Interactions due to drug association were discussed., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

NONOates are chemical compounds that are stable as solids but generate nitric oxide (NO) in aqueous solutions. When nebulized or instilled intratracheally, NONOates can attenuate pulmonary hypertension in adult animals with lung injury. To assess the effect of a nebulized NONOate, DPTA/NO, on group B Streptococcus (GBS)-induced pulmonary hypertension in newborn piglets, we studied 20 anesthetized and mechanically ventilated piglets (4-10 d). They were randomly assigned to receive nebulized placebo solution or DPTA/NO (100 mg) 15 min after sustained pulmonary hypertension. Pulmonary artery and wedge, systemic, and right atrial pressures; cardiac output; and arterial blood gases were obtained at baseline and every 15 min during 120 min of continuous GBS infusion (6 x 10(8) CFU/min). Methemoglobin levels were measured at baseline and 60 min. A significant decrease in pulmonary artery pressure, pulmonary vascular resistance (PVR), systemic arterial pressure, and systemic vascular resistance (SVR) was observed after DPTA/NO nebulization (p <0.001). Whereas the increase in PVR/SVR observed after GBS infusion was sustained for 120 min in the placebo group, this ratio decreased after DPTA/NO nebulization and remained significantly lower throughout the study period (p <0.01). Cardiac output, arterial blood gases, and methemoglobin values did not differ between groups. These data demonstrate that the pulmonary hypertension induced by GBS infusion is markedly attenuated by DPTA/NO nebulization. The lower PVR/SVR observed in the treated group indicates that the vasodilatory effect of NONOate is more pronounced in the pulmonary than systemic vasculature. Therefore, NONOates may have clinical application in the management of pulmonary hypertension secondary to sepsis in neonates.

It has been suggested that one of the mechanisms of action of cyclosporin is by abrogation of major histocompatibility complex class II expression. We have tested this hypothesis by following the expression of DR7, a polymorphic determinant of the class II DR locus in cardiac biopsies from 12 heart or heart-lung recipients who were themselves DR7 negative but whose donors were DR7 positive. All patients received cyclosporine and azathioprine immunosuppression. Immunoperoxidase and immunofluorescent techniques were used. The DR7 determinant was found on interstitial structures on donor heart at all times studied, including at 2 years after transplantation. Double immunofluorescent labeling of donor heart before transplantation revealed that more than 60% of the DR7 was on endothelial cells. At later times the proportion of DR7 on endothelial cells increased, but even at 1 year some DR7 was found on interstitial structures not of endothelial origin. The significance of these findings to mechanisms of long-term immunosuppression is discussed.

Expression of beta human chorionic gonadotropin (beta hCG) by bladder tumours has been shown to be associated with increased metastases and resistance to treatment with radiotherapy and chemotherapy. Preliminary results from typing frozen tumours using monoclonal antibodies against HLA determinants show reduced or lost expression of one or more antigens in two thirds of patients studied with a trend for more malignant behaviour and inability to generate tumour infiltrating lymphocyte expression using Interleukin-2 in those patients whose tumours demonstrate loss. In this series beta hCG expression was only seen in a subgroup of those demonstrating loss of HLA antigen expression. Studies of beta hCG secreting bladder cancer cell lines showed that it was possible to induce class II HLA antigen expression with gamma Interferon, and that this treatment but not alpha Interferon reduced beta hCG production by the cell line.