Characterization of rubrene polycrystalline thin film transistors fabricated using various heat-treatment conditions

We observed the crystal structure changes of rubrene (5,6,11,12-tetraphenylnaphthacene) polycrystal thin films on SiO₂/Si(100) substrates at various heat-treatment temperatures by X-ray diffraction, and a near-field microwave microprobe technique. An amorphous rubrene thin film was initially observed at heat-treatment temperature of 35 °C. After the treatment with in-situ vacuum post-annealing at 80 °C for 22 h, the rubrene thin film was transformed from the amorphous phase into a crystalline phase of orthorhombic structure. We could obtain a higher field effect mobility of 0.047 cm²/V·s and lower threshold voltage of − 4 V for the following heat-treatment process: pre-annealing at 80 °C, cooling at 40 °C, and post-annealing at 80 °C for 22 h.     

New genetic loci that control susceptibility and symptoms of experimental allergic encephalomyelitis in inbred mice

Experimental allergic encephalomyelitis (EAE), the principal animal model of multiple sclerosis, is a genetically determined phenotype. In this study, analyses of the cumulative disease frequencies in parental, F1 hybrid, and F2 mice, derived from the EAE-susceptible SJL/J strain and the EAE-resistant B10.S/DvTe strain, confirmed that susceptibility to EAE is not inherited as a simple Mendelian trait. Whole genome scanning, using 150 informative microsatellite markers and a panel of 291 affected and 390 unaffected F2 progeny, revealed significant linkage of EAE susceptibility to marker loci on chromosomes 7 (eae4) and 17, distal to H2 (eae5). Quantitative trait loci for EAE severity, duration, and onset were identified on chromosomes 11 (eae6, and eae7), 2 (eae8), 9 (eae9), and 3 (eae10). While each locus reported in this study is important in susceptibility or disease course, interactions between marker loci were not statistically significant in models of genetic control. One locus, eae7, colocalizes to the same region of chromosome II as Orch3 and Idd4, susceptibility loci in autoimmune orchitis and insulin-dependent diabetes mellitus, respectively. Importantly, eae5 and eae7 are syntenic with human chromosomes 6p21 and 17q22, respectively, two regions of potential significance recently identified in human multiple sclerosis genome scans.     

Biochemical analysis of ++Prospero protein during asymmetric cell division: cortical Prospero is highly phosphorylated relative to nuclear Prospero

Hippocampal synapses express two distinct forms of the long-term potentiation (LTP), i.e. NMDA receptor-dependent and -independent LTPs. To understand its molecular-anatomical basis, we produced affinity-purified antibodies against the GluRepsilon1 (NR2A), GluRepsilon2 (NR2B), and GluRzeta1 (NR1) subunits of the N-methyl-D-aspartate (NMDA) receptor channel, and determined their distributions in the mouse hippocampus. Using NMDA receptor subunit-deficient mice as the specificity controls, section pretreatment with proteases (pepsin and proteinase K) was found to be very effective to detect authentic NMDA receptor subunits. As the result of modified immunohistochemistry, all three subunits were detected at the highest level in the strata oriens and radiatum of the CA1 subfield, and high levels were also seen in most other neuropil layers of the CA1 and CA3 subfields and of the dentate gyrus. However, the stratum lucidum, a mossy fibre-recipient layer of the CA3 subfield, contained low levels of the GluRepsilon1 and GluRzeta1 subunits and almost excluded the GluRepsilon2 subunit. Double immunofluorescence with the AMPA receptor GluRalpha1 (GluR1 or GluR-A) subunit further demonstrated that the GluRepsilon1 subunit was colocalized in a subset, not all, of GluRalpha1-immunopositive structures in the stratum lucidum. Therefore, the selective scarcity of these NMDA receptor subunits in the stratum lucidum suggests that a different synaptic targeting mechanism exerts within a single CA3 pyramidal neurone in vivo, which would explain contrasting significance of the NMDA receptor channel in LTP induction mechanisms between the mossy fibre-CA3 synapse and other hippocampal synapses.     

Locus heterogeneity for Waardenburg syndrome is predictive of clinical subtypes

Waardenburg syndrome (WS) is a dominantly inherited and clinically variable syndrome of deafness, pigmentary changes, and distinctive facial features. Clinically, WS type I (WS1) is differentiated from WS type II (WS2) by the high frequency of dystopia canthorum in the family. In some families, WS is caused by mutations in the PAX3 gene on chromosome 2q. We have typed microsatellite markers within and flanking PAX3 in 41 WS1 kindreds and 26 WS2 kindreds in order to estimate the proportion of families with probable mutations in PAX3 and to study the relationship between phenotypic and genotypic heterogeneity. Evaluation of heterogeneity in location scores obtained by multilocus analysis indicated that WS is linked to PAX3 in 60% of all WS families and in 100% of WS1 families. None of the WS2 families were linked. In those families in which equivocal lod scores (between -2 and +1) were found, PAX3 mutations have been identified in 5 of the 15 WS1 families but in none of the 4 WS2 families. Although preliminary studies do not suggest any association between the phenotype and the molecular pathology in 20 families with known PAX3 mutations and in four patients with chromosomal abnormalities in the vicinity of PAX3, the presence of dystopia in multiple family members is a reliable indicator for identifying families likely to have a defect in PAX3.     

The cortical regulation of lactogenesis and lactopoiesis

The mammary gland secretory activity, blood circulation, respiration, gas-energy exchange and feed efficiency were studied in cows of a strong (S) and weak (W) types of the nervous system. In the W cows, the lactating dominant was found to be weak, their mammary gland's secretory activity increased less obviously and was stabilised at a lower level than in the S cows.     

Haplotype and phenotype analysis of six recurrent BRCA1 mutations in 61 families: results of an international study

Central to the Mu transpositional recombination are the two chemical steps; donor DNA cleavage and strand transfer. These reactions occur within the Mu transpososome that contains two Mu DNA end segments bound to a tetramer of MuA, the transposase. To investigate which MuA monomer catalyzes which chemical reaction, we made transpososomes containing wild-type and active site mutant MuA. By pre-loading the MuA variants onto Mu end DNA fragments of different length prior to transpososome assembly, we could track the catalysis by MuA bound to each Mu end segment. The donor DNA end that underwent the chemical reaction was identified. Both the donor DNA cleavage and strand transfer were catalyzed in trans by the MuA monomers bound to the partner Mu end. This arrangement explains why the transpososome assembly is a prerequisite for the chemical steps.     

Knowledge of Home Dialysis Among Inner‐City Satellite Hemodialysis Patients

There is limited use of home renal replacement therapies in the U.S.A. One percent of dialysis patients are on home hemodialysis (HHD) and only 9% undergo peritoneal dialysis (PD). In an effort to better understand this, 161 satellite hemodialysis patients in 6 units in Brooklyn were surveyed. Forty‐eight percent of patients were women, 86% were black, 5% white, 8% Hispanic, and 1% other. Mean age was 49.4 years (range 22 – 69 years). Etiology of renal disease was hypertension (41%), diabetes mellitus (31%), polycystic kidney disease (3%), systemic lupus erythematosus (4%), and other or unknown (21%). Patients were queried about knowledge of and attitudes toward home therapies. Seventy‐nine percent of patients knew of home dialysis. The source of this information was the nephrologist (59%), the social worker (14%), a nurse (8%), other patients (4%), and other sources (15%). Only 10% of patients had ever considered HHD. Fifty‐four percent were afraid to do self‐care at home and 35% were not interested. Surprisingly, only 3% felt they had no reliable helper and 8% felt that their housing was not suitable. Similarly, 78% of patients had been spoken to about PD, but only 11% had considered it. Forty‐one percent were afraid of doing self‐care on PD, and 45% were not interested. We conclude that, although the majority of patients in six inner‐city dialysis units had heard of home dialysis, only a small number ever considered it. As many patients were afraid of doing home therapy, better education about the risks and benefits needs to be disseminated.     

Three-dimensional structure of the plant photosystem II reaction centre at 8 A resolution

Photosystem II is a multisubunit enzyme complex involved in plant photosynthesis. It uses solar energy to catalyse the breakdown of water to reducing equivalents and molecular oxygen. Native photosystem II comprises more than 25 different subunits, and has a relative molecular mass of more than 600K. Here we report the three-dimensional structure of a photosystem II subcomplex, containing the proteins D1, D2, CP47 and cytochrome b-559, determined by electron crystallography. This CP47 reaction centre, which has a relative molecular mass of 160K, can perform light-mediated energy and electron-transfer reactions but is unable to oxidize water. The complex contains 23 transmembrane alpha-helices, of which 16 have been assigned to the D1, D2 and CP47 proteins. The arrangement of these helices is remarkably similar to that of the helices in the reaction centres of purple bacteria and of plant photosystem I, indicating a common evolutionary origin for these assemblies. The map suggests that redox cofactors in the D1-D2 complex are located in positions analogous to those in the bacterial reaction centre, but the distance between the chlorophylls corresponding to the bacterial 'special pair' is significantly larger.     

Relation of stressors and depressive symptoms to clinical progression of viral illness

OBJECTIVE: The aim of this research was to determine whether and in whom stressors and depressive symptoms facilitate clinical recurrence of herpes simplex virus (HSV) and progression of HIV. METHOD: Meta-analytic techniques were used to review the relations of stressors and depressive symptoms to clinical recurrence of HSV in 16 published studies and to indicators of HIV progression in 19 published studies. The authors calculated average effect sizes, performed fixed effect and random effect inferential analyses, tested for heterogeneous findings, and identified potential moderating variables. RESULTS: Depressive symptoms were associated with a slightly increased risk of HSV recurrence and increased reports of HIV-related symptoms, whereas stressors were not. However, depressive symptoms were not associated with objective indicators of accelerated HIV progression. Stressor studies, especially those that ascertained population-specific life events, found numerical and functional decrements in circulating natural killer cell populations. The candidate moderators identified include, for HSV recurrence, age, sex, and medication status, and for HIV-related symptoms, age, race, disease stage, and co-infection with HSV. CONCLUSIONS: Depressive symptoms, but not stressors, increase the risk of HSV recurrence generally. Depressive symptoms do not appear to accelerate HIV progression ubiquitously, although they are associated with increased reporting of HIV-related symptoms. Future studies that ascertain population-specific stressors should determine whether reductions in cytotoxic lymphocytes influence HIV disease progression. Moreover, researcher should investigate the role of the identified moderators and recognize psychoimmune moderators in existing and novel study groups. These analyses could confirm that certain individuals are especially susceptible to the effects on disease progression of stressors, depressive symptoms, or both.