SUMMARYAllergen-reactive T helper type-2 (Th2) cells and proinflammatory cytokines have been suggested to play an important role in the induction and maintenance of the inflammatory cascade in allergic asthma. We compared the plasma concentrations of novel proinflammatory cytokines IL-17 and IL-18, other proinflammatory cytokines IL-6 and IL-12, Th2 cytokines IL-10 and IL-13, and intracellular interferong (IFN-g) and IL-4 in Th cells of 41 allergic asthmatics and 30 sex-and age-matched health control subjects. Plasma cytokines were measured by enzyme-linked immunosorbent assay. Intracellular cytokines were quantified by flow cytometry. Plasma IL-18, IL-12, IL-10, IL-13 concentrations were significantly higher in allergic asthmatic patients than normal control subjects (IL-18: median 228´35 versus 138´72 pg/ml, P , 0´001; IL-12: 0´00 versus 0´00 pg/ml, P 0´001; IL-10: 2´51 versus 0´05 pg/ml, P , 0´034; IL-13: 119´38 versus 17´89 pg/ml, P , 0´001). Allergic asthmatic patients showed higher plasma IL-17 and IL-6 concentrations than normal controls (22´40 versus 11´86 pg/ml and 3´42 versus 0´61 pg/ml, respectively), although the differences were not statistically significant (P 0´077 and 0´053, respectively). The percentage of IFN-g-producing Th cells was significantly higher in normal control subjects than asthmatic patients (23´46 versus 5´72%, P , 0´001) but the percentage of IL-4 producing Th cells did not differ (0´72 versus 0´79%, P . 0´05). Consequently, the Th1/Th2 cell ratio was significantly higher in normal subjects than asthmatic patients (29´6 versus 8´38%, P , 0´001). We propose that allergic asthma is characterized by an elevation of both proinflammatory and Th2 cytokines. The significantly lower ratio of Th1/Th2 cells confirms a predominance of Th2 cells response in allergic asthma.

Rationale Activation of the mitochondrial ATP-sensitive potassium channel (mitoKATP) has been implicated in the mechanism of cardiac ischemic preconditioning, yet its molecular composition is unknown. Objective To use an unbiased proteomic analysis of the mitochondrial inner membrane to identify the mitochondrial K+ channel underlying mitoKATP. Methods and Results Mass spectrometric analysis was used to identify KCNJ1(ROMK) in purified bovine heart mitochondrial inner membrane and confirmed that ROMK mRNA is present in neonatal rat ventricular myocytes and adult hearts. ROMK2, a short form of the channel, is shown to contain an N-terminal mitochondrial targeting signal and a full length epitope-tagged ROMK2 colocalizes with mitochondrial ATP synthase β. The high-affinity ROMK toxin, tertiapin Q, inhibits mitoKATP activity in isolated mitochondria and in digitonin-permeabilized cells. Moreover, shRNA-mediated knockdown of ROMK inhibits the ATP-sensitive, diazoxide activated, component of mitochondrial thallium uptake. Finally, the heart-derived cell line, H9C2, is protected from cell death stimuli by stable ROMK2 overexpression, while knockdown of the native ROMK exacerbates cell death. Conclusions The findings support ROMK as the pore-forming subunit of the cytoprotective mitoKATP channel.

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Before isolation of all patients with clinically confirmed or suspected SARS, routine use of several protective devices, and training of staff in infection control, many health care workers were infected with SARS from patients with unsuspected cases.

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Respiratory disease is responsible for the highest health-care burden locally. Increased efforts in improving management and prevention of these diseases, including tobacco control, improving air quality and vaccination against influenza and pneumococci, are necessary.

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Rationale Stimulation of β3-adrenoreceptors (β3-AR) blunts contractility and improves chronic left ventricular function in hypertrophied and failing hearts in a neuronal nitric oxide synthase (nNOS) dependent manner. nNOS can be regulated by post-translational modification of stimulatory phosphorylation residue Ser1412 and inhibitory residue Ser847. However, the role of phosphorylation of these residues in cardiomyocytes and β3-AR protective signaling has yet to be explored. Objective We tested the hypothesis that β3-AR regulation of myocyte stress requires changes in nNOS activation mediated by differential nNOS phosphorylation. Methods and results Endothelin (ET-1) or norepinephrine induced hypertrophy in rat neonatal ventricular cardiomyocytes (NRVMs) was accompanied by increased β3-AR gene expression. Co-administration of the β3-AR agonist BRL-37433 (BRL) reduced cell size and reactive oxygen species (ROS) generation, while augmenting NOS activity. BRL-dependent augmentation of NOS activity and ROS suppression due to NE were blocked by inhibiting nNOS (L-VNIO). BRL augmented nNOS phosphorylation at Ser1412 and dephosphorylation at Ser847. Cells expressing constitutively dephosphorylated Ser1412A or phosphorylated Ser847D nNOS mutants displayed reduced nNOS activity and a lack of BRL modulation. BRL also failed to depress ROS from NE in cells with nNOS-Ser847D. Inhibiting Akt decreased BRL-induced nNOS-Ser1412 phosphorylation and NOS activation, whereas Gi/o blockade blocked BRL-regulation of both post-translational modifications, preventing enhancement of NOS activity and ROS reduction. BRL resulted in near complete dephosphorylation of Ser847 and a moderate rise in Ser1412 phosphorylation in mouse myocardium exposed to chronic pressure-overload. Conclusion β3-AR regulates myocardial NOS activity and ROS via activation of nNOS involving reciprocal changes in phosphorylation at two regulatory sites. These data identify a novel and potent anti-oxidant and anti-hypertrophic pathway due to nNOS post-translational modification that is coupled to β3-AR receptor stimulation.