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Nitric oxide (NO), a free radical that is negatively inotropic in the heart and skeletal muscle, is produced in large amounts during sepsis by an NO synthase inducible (iNOS) by LPS and/or cytokines. The aim of this study was to examine iNOS induction in the rat diaphragm after Escherichia Coli LPS inoculation (1.6 mg/kg i.p.), and its involvement in diaphragmatic contractile dysfunction. Inducible NOS protein and activity could be detected in the diaphragm as early as 6 h after LPS inoculation. 6 and 12 h after LPS, iNOS was expressed in inflammatory cells infiltrating the perivascular spaces of the diaphragm, whereas 12 and 24 h after LPS it was expressed in skeletal muscle fibers. Inducible NOS was also expressed in the left ventricular myocardium, whereas no expression was observed in the abdominal, intercostal, and peripheral skeletal muscles. Diaphragmatic force was significantly decreased 12 and 24 h after LPS. This decrease was prevented by inhibition of iNOS induction by dexamethasone or by inhibition of iNOS activity by N(G)-methyl-L-arginine. We conclude that iNOS was induced in the diaphragm after E. Coli LPS inoculation in rats, being involved in the decreased muscular force.

We were able to detect nine methylated nucleobases (3-methyluracil, 1-, 2-, 3- and 7-methylguanine, 1-, 2-, 3- and 6-methyladenine) in RNA from rat and calf liver, baker's yeast, Torula and Euglena cells by using reversed-phase high-performance liquid chromatography and thermospray mass spectrometry. Total cellular, nuclear, cytoplasmic and poly (A)+ RNA from rat liver showed marked methylation, mainly of 1- and 3-methylguanine, and 3- and 2-methyladenine. These bases were especially abundant in nuclear RNA and, to a lesser extent, in poly (A)+ RNA. In contrast, 7-methylguanine and 6-methyladenine were poorly represented in poly (A)+ RNA.

Superconducting circuits are described by a small number of macroscopic variables and behave as simple quantum mechanical systems. They can be manufactured and integrated by extending micro-electronics techniques with suspended masks and shadow evaporation techniques. Superconducting circuits can be designed to study novel quantum phenomena and explore some of their applications. In this paper, the physics of some superconducting qubits circuits (phase and coupled charge-phase qubits) is reviewed. Other interesting applications involving quantised superconducting pumps and the current-phase relation of Josephson rhombi networks are also presented. Presently, applications of superconducting circuits to quantum computing are limited by decoherence phenomena. Prospects in material development and circuit integration to overcome these difficulties are also discussed in this review.

During human placental development trophoblast cells differentiate along either the villous cytotrophoblast (VCT) lineage to form the syncytiotrophoblast (ST) or the invasive extravillous cytotrophoblast (EVCT) lineage (1). Abnormalities in early differentiation processes are characteristic of poor placentation, which is associated with fetal growth restriction (FGR) and pre-eclampsia (PE), the major clinical complications of human pregnancy (2). A large family of homeobox gene transcription factors controls “cell-fate decisions” during development (3), but the expression profile and role of homeobox genes in the human trophoblast cell lineages is not well understood. The aim of the study was to determine homeobox gene expression in primary cultures of mononuclear VCT (2h) and EVCT (2 h) obtained from first trimester human chorionic villi of 8–12 weeks of gestation and in vitro differentiated ST (72 h) and invasive EVCT (48 h), respectively. The isolation and characterization of freshly isolated VCT, EVCT and in vitro differentiated ST and invasive EVCT were performed as described previously (1,4). The homeobox gene mRNA profile was performed using PCR arrays in a pooled sample of VCT and EVCT (n = 6 in each group) and further validated by real-time PCR. Homeobox gene expression studies revealed MSX2 mRNA levels were the highest in VCT (2 h) but undetectable in EVCT (2 h). Further comparisons of homeobox gene expression in in vitro differentiated ST to invasive EVCT showed marked increase in MSX2, DLX3, DLX4 and MEIS1 mRNA levels in ST, which are regulators of cellular differentiation in many studies. Homeobox genes HLX and HHEX, which are implicated in regulating cellular proliferation showed decreased mRNA levels in ST compared to invasive EVCT. Our results demonstrated several known placental and novel homeobox genes are differentially expressed in trophoblast cell lineages. Functional studies of these candidate genes will provide a better understanding of the molecular mechanisms of early placental development. (1) Tarrade et al. (2001) Lab Invest. 81, 1199–1211.(2) LokeYW and King A (1995) Cell Biology and Immunology, Cambridge ed.(3) J Cross et al. (2002) Recent Progress in Hormone Research 57: 221–234.(4) Handschuh et al. (2007) Placenta, 28, 175–184.

The serum level of alpha 1-acid glycoprotein (alpha 1-AGP) is significantly increased in various animal species by treatment with cytokines, glucocorticoids and phenobarbital. The mechanisms responsible for the cytokine-induced and glucocorticoid-induced increases are now well documented, but not so in the case of phenobarbital. The main purpose of this study was to assess whether phenobarbital acts on alpha 1-AGP synthesis in the liver at the transcriptional or translational level. Male Dark Agouti rats received 70 mg phenobarbital/kg daily for 7 days. The analysis of total hepatic RNA showed that a single injection of phenobarbital induced an 11-fold increase in phenobarbital-dependent cytochrome P450IIB mRNA, whereas seven injections of phenobarbital were required to induce a maximum 5.5-fold increase in alpha 1-AGP mRNA. Concurrently, the transcription rate of the alpha 1-AGP gene rose 3.5-fold. Hepatocytes isolated after the seventh injection of phenobarbital showed a threefold increased capacity to secrete alpha 1-AGP, corresponding to a 3.2-fold increased alpha 1-AGP mRNA content in the liver. In conditions in which its effect on the induction of alpha 1-AGP synthesis was maximum, phenobarbital caused a 30% reduction in liver albumin mRNA and in albumin secretion by isolated hepatocytes, resulting from a 60-70% reduction in the rate of transcription of the albumin gene measured in isolated nuclei. We conclude that the effect of phenobarbital on alpha 1-AGP and albumin gene expression occurs at the transcriptional rather than the translational level.

– In Sect. 2.2 on the thermal gradients, the spatial coordinate running along the structure should be z (and not x) according to the schematic in Fig. 1. – In Sect. 3.2.1 on the normal modes, the beam equation’s spatial coordinate should also read z (and not x) for the same reason. – In the theoretical part, the definition of both the spring constant and mass is per foot of the structure. Therefore in Sect. 3.2.2, as can be deduced from (15), the k n present in (16) and (17) and their related simplified Lorentz expressions should read 2k n . The expression for Xmax should also refer to 2k (j) n , and ω, δω should contain 2m n (instead of m (j) n ). – For the same reason, in (24) and (25) according to equation (23), one should replace kv0 (one foot’s spring constant) with 2kv0 + kv . – In the expressions of the bi ’s (the non-linear coefficients), the numerical prefactor 8 weighting 21 (non-linear reactive term) should be replaced by 2.

Human cytomegalovirus (HCMV) contributes to pathogenic processes in immuno-suppressed individuals, in fetuses and in neonates. Infection during pregnancy is known to cause miscarriages and low-birthweight newborns and we know that in this case infection of the placenta precedes transmission to the fetus. HCMV was shown to benefit from inflammatory conditions by using the cyclooxygenase-2 (Cox-2)-dependent prostaglandin pathway for transcription of the essential immediate-early gene IE2. The fact that Cox-2 activation could serve as a source of ligand for the nuclear receptor peroxisome proliferator-activated receptor gamma (PPARγ), which is known to play a pivotal role in controlling human trophoblast invasion, led us to hypothesize that HCMV could impair placentation through activation of PPARγ.

The ability of the fetal rat to respond to interleukin 1 beta (IL1 beta) by expressing alpha 1-acid glycoprotein (AGP) was investigated. Eight and 20 h after injection of 7 ng IL1 beta into 19-day fetuses, liver AGP mRNA increased by a factor of 66 and 82 respectively, while serum AGP levels increased by a factor of 3 and 5. Similar treatment of the mothers altered in the fetuses neither AGP serum levels nor the amount of liver AGP mRNA. The induction of AGP gene expression in the fetal liver in response to IL1 beta was similar to that observed in the adult liver. These results demonstrate that at day 19 the fetal rat liver has acquired a mature acute-phase system.

Thermal conductance measurements are presented on nanostructured individual single crystalline Si suspended nanowires at low temperature. The mechanically suspended silicon nanowires with different sizes (130nm by 100nm and 130 nm by 200nm) are fabricated by e-beam lithography from Silicon On Insulator (SOI) substrate. The thermal conductance of the ballistic phonon wave guides is measured by means of an ac technique, the 3 ω method, using a niobium nitride transducer deposited on top. The geometry of the nanowire is chosen to match the order of magnitude of the dominant phonon wave length in silicon at low temperature which is of the order of 100 nm at 1K. A regular cubic law is observed at high temperature, but a deviation is measured at the lowest temperature with a saturation of thermal conductance which is attributed to the reduced geometry of the nanowire. The experimental results are in agreement with the Casimir theory taking into account the surface state (roughness) of the silicon wire. The deviation observed at low temperature is a clear signature of the consequence of the low dimentionality of the wire as well as the surface effects on the phonon transport.

In previous studies on arachidonic acid (AA) metabolism by pulmonary macrophages in vitro, we observed that the presence of serum in the culture medium influenced the profile of AA metabolites released. To further characterize this phenomenon, rat alveolar macrophages were placed in plastic tissue culture dishes and allowed to adhere in the presence or absence of 7.5% fetal bovine serum (FBS) for 1 h. Adherent cells were then maintained in medium (equilibration) with or without FBS for 3.5 h before stimulation with the calcium ionophore A23187. The release of thromboxane B2 (TXB2) (the stable metabolite of TXA2) and leukotriene B4 (LTB4) during culture was measured by radioimmunoassay and reverse-phase high pressure liquid chromatography, respectively, at the end of each culture step. Cell adhesion to the plastic substrate in FBS-free medium induced an intense stimulation of AA metabolism, with the release of both TXB2 and LTB4. Adhesion and the accompanying TXB2 release appear to be mediated by trypsin-sensitive components since trypsin-pretreated macrophages showed a dramatic reduction in both adherence and TXB2 synthesis. The presence of FBS during the attachment phase of culture reduced both adhesion and release of TXB2 and LTB4 by more than 50%. On the other hand, addition of FBS to cells that had completed adhesion in serum-free medium stimulated release of both metabolites. When challenged with calcium ionophore after 4.5 h of culture, macrophages that had adhered in FBS-free medium released a much smaller amount of TXB2 than did macrophages that had been cultured in the presence of FBS.(ABSTRACT TRUNCATED AT 250 WORDS)

DTA was carried out as a function of partial oxygen pressure on samples of nominal compositions BiSrCaCu 2 O x , Bi 1.2 SrCaCu 2 O x , Bi 2 Sr 2 Ca 2 Cu 3 O x , Bi 2 Sr 1.5 Ca 1.9 Cu 3.4 O x and Bi 4 PbSr 4 Ca 5 Cu 7 O x . Two reversible DTA peaks (endothermic on heating) were observed: a multiple peak I at 745–770°C, decreasing with increasing P (O 2 ), and a single peak II at 835–875°C, increasing in intensity and temperature with increasing P (O 2 ). Quenching at reduced P (O 2 ) showed that peak I mainly consists of the reaction Bi 2 Sr 2 Ca 1 Cu 2 O x →Bi 2 (Sr 2− x Ca x )CuO x with much lower T c . Peak II is ascribed to the incongruent melting of Bi 2 Sr 2 Ca 1 Cu 2 O x . Unlike peak I, the latter is a redox reaction involving gaseous oxygen; its enthalpy is ≈90 kJ/mol (O 2 ). In the Pb-substituted system, peak II is strong at lower P (O 2 ) and clearly split, possibly indicating the range of stabilization of Bi 2− x Pb x Sr 2 Ca 2 Cu 3 O x . Pure 110 K transitions were obtained for Bi 4 PbSr 4 Ca 5 Cu 7 O x annealed at 835°C and 0.05 atm O 2 .

We present a novel shadow evaporation technique for the realization of junctions and capacitors. The design by e-beam lithography of strongly asymmetric undercuts on a bilayer resist enables in situ fabrication of junctions and capacitors without the use of the well-known suspended bridge (Dolan 1977 Appl. Phys. Lett. 31 337-9). The absence of bridges increases the mechanical robustness of the resist mask as well as the accessible range of the junction size, from 10(-2) µm(2) to more than 10(4) µm(2). We have fabricated Al/AlO(x)/Al Josephson junctions, phase qubit and capacitors using a 100 kV e-beam writer. Although this high voltage enables a precise control of the undercut, implementation using a conventional 20 kV e-beam is also discussed. The phase qubit coherence times, extracted from spectroscopy resonance width, Rabi and Ramsey oscillation decays and energy relaxation measurements, are longer than the ones obtained in our previous samples realized by standard techniques. These results demonstrate the high quality of the junction obtained by this bridge-free technique.