Theoretical studies of optoelectronic,magnetization and heat transport properties of conductive metal adatoms adsorbed on edge chlorinated nanographenes

The electronic structures, magnetization and quantum transport properties of edge chlorinated nanographenes (Cl NGRs) (C1–C3) functionalized with conductive metal adatoms (Al, Au and Cu) has been investigated by means of density functional theory (DFT) with periodic boundary conditions and plane wave basis functions. The adsorption energy results depict weak chemisorption and strong physisorption for Au adsorption for C1, while C2 and C3 show strong chemisorption towards the studied metals. The role of dispersion forces has also been studied with an empirical classical model. The results show that the metal clusters avoid hollow sites on the Cl NGRs surface and favor atop and bond sites. The net magnetic moment of 0.73 μ_B is observed for the (Cl NGRs–metals) system and is in reasonable agreement with the previous calculations carried out on graphene nanoribbons. The TDDFT calculations predict that the absorption spectra for metal dimer–Cl NGRs lie in the visible region. The predictive electrical conductivity of these systems suggests that the metal adatoms play an important role in the transport properties of devices and can be used for thermoelectric applications.

The electronic structures, magnetization and quantum transport properties of edge chlorinated nanographenes functionalized with conductive metal adatoms have been investigated by means of density functional theory with plane wave basis functions.     

Stimulation of Mitochondrial Adenosine Diphosphate Uptake by Thyroid Hormones

Thyroid hormone administered in vivo increased carrier-mediated (atractyloside-sensitive) ADP uptake by rat liver mitochondria. 3 Days after a single large dose of triiodothyronine (20 mug/100 g of body weight), mitochondrial uptake of ADP measured at 6 degrees was 2.35 +/- 0.17 nmol/min per mg of protein, compared with an uptake of 1.81 +/- 0.19 nmol/min per mg of protein in mitochondria from untreated rats (P < 0.025). Cyanide (1.33 mM) had no effect on ADP uptake by mitochondria from either untreated or triiodothyronine-treated animals. Uptake of ADP by mitochondria from thyroidectomized rats treated with thyroxine for 7 days was 2.89 +/- 0.40 nmol/min per mg in mitochondria from thyrotoxic rats (20 mug of thyroxine per 100 g per day) and 1.98 +/- 0.22 nmol/min per mg in mitochondria from euthyroid rats (2 mug of thyroxine per 100 g per day) (P < 0.025). Mitochondria from both untreated and thyroid hormone-treated rats displayed a highly significant linear correlation between ADP uptake and ADP-dependent (i.e., state 3 minus state 4) oxygen consumption. There was, however, no difference in respiratory control ratios between mitochondria from euthyroid and thyrotoxic animals. Administration of dinitrophenol (2 mg/100 g) also stimulated carrier-mediated ADP uptake, but respiratory control of mitochondria from dinitrophenol-treated animals was virtually abolished. Triiodothyronine in vitro, at concentrations of 100 and 0.1 nM, appeared to inhibit rather than stimulate the uptake of mitochondrial ADP. The relationship between these observations and the clinical manifestations of thyrotoxicosis is discussed from the point of view of the possible effects of increased mitochondrial ADP transport on oxidative phosphorylation and adenosyl nucleotide metabolism.     

Developing a healthy living intervention for people with early psychosis using the Medical Research Council's guidelines on complex interventions: phase 1 of the HELPER - InterACT programme

BackgroundYoung people with early psychosis often gain a significant amount of weight after the initiation of anti-psychotic treatment. Despite the current policy guidance to develop and evaluate ‘healthy living’ interventions for people with psychosis there remains a paucity of research. Our aim was to develop an acceptable, feasible, culturally sensitive and potentially effective ‘healthy living’ intervention, specifically for young people with early psychosis.MethodsUsing the Medical Research Council guidelines for developing and evaluating complex interventions we conducted a number of studies to devise a ‘healthy living’ intervention. We used a ‘top down’ (published evidence), bottom up (stakeholder perspectives) approach, which included updating a systematic review, identifying a theoretical basis for the intervention, exploring the perspectives of service users and health professionals, and identifying key cultural issues. The results of these studies were synthesised to determine the content and delivery of the intervention.ResultsThe intervention developed comprised eight individual sessions to be delivered by a support time recovery worker over a 12 month period with emphasis on individualised action plans to facilitate participatory exercise and changes in diet. To optimise engagement, choice and self management a booklet and website were developed to provide participants with educational advice, healthy eating recipes and other materials.ConclusionUsing the Medical Research Council guidelines we have developed a potentially effective, feasible and acceptable ‘healthy living’ intervention for people with psychosis using early intervention services in the UK.     

Riboflavin instability is a key factor underlying the requirement of a gut microbiota for mosquito development

We previously determined that several diets used to rear Aedes aegypti and other mosquito species support the development of larvae with a gut microbiota but do not support the development of axenic larvae. In contrast, axenic larvae have been shown to develop when fed other diets. To understand the mechanisms underlying this dichotomy, we developed a defined diet that could be manipulated in concert with microbiota composition and environmental conditions. Initial studies showed that axenic larvae could not grow under standard rearing conditions (27 °C, 16-h light: 8-h dark photoperiod) when fed a defined diet but could develop when maintained in darkness. Downstream assays identified riboflavin decay to lumichrome as the key factor that prevented axenic larvae from growing under standard conditions, while gut community members like Escherichia coli rescued development by being able to synthesize riboflavin. Earlier results showed that conventional and gnotobiotic but not axenic larvae exhibit midgut hypoxia under standard rearing conditions, which correlated with activation of several pathways with essential growth functions. In this study, axenic larvae in darkness also exhibited midgut hypoxia and activation of growth signaling but rapidly shifted to midgut normoxia and arrested growth in light, which indicated that gut hypoxia was not due to aerobic respiration by the gut microbiota but did depend on riboflavin that only resident microbes could provide under standard conditions. Overall, our results identify riboflavin provisioning as an essential function for the gut microbiota under most conditions A. aegypti larvae experience in the laboratory and field.

Diet crucially affects the health of all animals (1). Most animals have a gut microbiota that can also affect host health both positively and negatively (2–6). However, understanding of the mechanisms underlying the effects of the gut microbiota remains a major challenge. This is because animals often consume complex or variable diets, and harbor large, multimember microbial communities that can result in many interactions that hinder identification of the factors responsible for particular host responses (2, 6–11). Metaanalyses and multiomic approaches can provide inferential insights on how diet–microbe or microbe–microbe interactions affect hosts (11–18), but functional support can be difficult to generate if proposed mechanisms cannot be studied experimentally (2, 14). Thus, study systems where hosts can be reared on defined diets with or without a microbiota of known composition can significantly advance mechanistic insights by providing the means to control and manipulate dietary, microbial, and environmental variables that potentially affect a given host response (19–21).Mosquitoes are best known as insects that blood feed on humans and other vertebrates. Only adult-stage female mosquitoes blood feed, which is required for egg formation by most species (22). Blood feeding has also led to several mosquitoes evolving into vectors that can transmit disease-causing microbes between hosts (22). In contrast, the juvenile stages of all mosquitoes are aquatic, with most species feeding on detritivorous diets (22–24). Larvae hatch from eggs with no gut microbiota but quickly acquire relatively low-diversity communities from the environment by feeding (25). Most gut community members are aerobic or facultatively anaerobic bacteria in four phyla (Actinobacteria, Bacteroidetes, Firmicutes, Proteobacteria), although other microbes, such as fungi and apicomplexans, have also been identified (25–39). Gut community composition also commonly varies within and between species as a function of where larvae develop, diet, and other variables (28–30, 32, 34, 40–42).Aedes aegypti has a worldwide distribution in tropical and subtropical regions, and is the primary vector of the agents that cause yellow fever, dengue fever, and lymphatic filariasis in humans (43). Preferentially living in urban habitats, females lay eggs in water-holding containers with microbial communities, and larvae molt through four instars before pupating and emerging as adults (30, 35, 41, 43). Conventionally reared cultures with a gut microbiota are usually maintained in the laboratory under conditions that mimic natural habitats with rearing temperatures of 25 to 28 °C and a 12- to 16-h light: 8- to 12-h dark photoperiod (44–46). Most insects that require microbial partners for survival live on nutrient-poor diets where microbes provision nutrients that cannot be synthesized or produced in sufficient abundance by the host (3). Mosquito larvae can experience resource limitations in the field (23–25), but in the laboratory are reared on undefined, nutrient-rich diets, such as rodent chow, fish food flakes, or mixtures of materials like liver powder, fish meal, and yeast extract (44–46). Nonetheless, our previous studies indicated that axenic A. aegypti as well as other species consume but fail to grow beyond the first instar when fed several diets that support the development of nonsterile, conventionally reared larvae (30, 47–49). Escherichia coli and several other bacteria identified as gut community members could colonize the gut (producing monoxenic, gnotobiotic larvae) and rescue development, but feeding axenic larvae dead bacteria could not (30, 35, 47). The presence of a gut microbiota in conventional and gnotobiotic but not axenic larvae was also associated with midgut hypoxia and activation of several signaling pathways with growth functions (50, 51). Finally, our own previous results using a strain of E. coli susceptible to ampicillin (50), and more recently a method for clearing an auxotrophic strain of E. coli from gnotobiotic larvae (52), both showed that the proportion of individuals that develop into adults correlates with the duration that larvae have living bacteria in their gut.Altogether, the preceding results suggested that A. aegypti and several other mosquitoes require a gut microbiota for development. In contrast, another recent study showed that axenic A. aegypti larvae develop into adults, albeit more slowly than larvae with a gut microbiota, when fed diets comprised of autoclaved bovine liver powder (LP) and brewer’s yeast (Saccharomyces cerevisiae) extract (YE) or autoclaved LP, YE, and E. coli (EC) embedded in agar (53). This latter finding suggests the undefined dietary components used provide factors larvae require for development into adults, whereas a gut microbiota was also required to provide these factors under the conditions in which our own previous studies were conducted. The goal of this study was to identify what these factors are. Toward this end, we first assessed the growth of axenic A. aegypti when fed diets containing autoclaved LP, YE, and EC under different conditions. We then used this information to develop a defined diet that allowed us to systematically manipulate nutrient, microbial, and environmental variables. We report that the instability of riboflavin is a key factor underlying why A. aegypti larvae require a gut microbiota under most conditions experienced in the laboratory and field.     

Telomeric fusion as a mechanism for the loss of 1p in meningioma

Characteristic cytogenetic aberrations are found in the various histopathological designations of meningioma. These aberrations range from the loss of 22q in histologically benign tumors to complex hypodiploid karyotypes in atypical and malignant tumors. This progression is characterized by increasing chromosome loss and instability, with a critical step being the loss of 1p. We report a detailed cytogenetic investigation of chromosome aberrations in a series of 88 meningiomas using Giemsa banding and multicolor spectral karyotyping (SKY). Clonal chromosome aberrations were identified in 46 (52%) tumors by G banding. Thirty-five tumors showing complex chromosome aberrations not fully characterized by G banding were subsequently reanalyzed by SKY. The SKY technique refined the G-band findings in 18 (51%) of the tumors on which it was applied. The most common features of cytogenetic progression in the complex karyotypes were chromosome arm-specific losses relating to the formation of deletions and dicentric chromosomes involving 1p. Part or all of 1p was lost in 19 tumors. Five tumors showed evidence for the loss of 1p in a progressive step-wise series of telomeric fusions involving the formation of unstable intermediates. Five recurring dicentric chromosomes were identified, including dic (1;11)(p11;p11), dic(1;12)(p12 approximately p13;p11), dic(1;22)(p11;q12 approximately q13), dic(7;19)(p11;p11), and dic(19;22)(p11 approximately p13;q11 approximately q13). These findings provide evidence that telomeric fusions play a role in the formation of clonal deletions, dicentrics, and unbalanced translocations of 1p. The loss of 1p has possible diagnostic and prognostic implications in the management of meningioma.     

Value of fine‐needle aspiration biopsy in initial evaluation of floor of the mouth masses: Report of a case of low‐grade mucoepidermoid carcinoma

Low‐grade mucoepidermoid carcinoma (LG MEC) is a rare tumor which can occur in the minor salivary glands as intraoral lesion, more frequently in the palate and very rarely in the floor of the mouth. Traditionally, the diagnosis has been made on surgical resection specimens only. There is new growing evidence that these lesions can be accurately diagnosed by a fine‐needle aspiration (FNA) biopsy procedure. In this article, we report a case of LG MEC of the floor of mouth diagnosed by FNA and confirmed by subsequent surgical resection. We also provide clues for high index of suspicion for these rare lesions, both clinically and morphologically. Diagn. Cytopathol. 2010. © 2009 Wiley‐Liss, Inc.     

Hepatitis B virus BCP,precore/core,X gene mutations/genotypes and the risk of hepatocellular carcinoma in India

The study aims to characterize mutations of the HBV genome involving BCP, Precore/core and X regions and also defines HBV genotypes in patients of hepatocellular carcinoma (HCC). The study involved 150 HBV‐related HCC cases and 136 HBV‐related chronic liver disease patients without HCC as controls. HBV DNA was subjected to mutational analysis using SSCP technique, genotyping by RFLP, and direct nucleotide sequencing. HBV DNA was found in 58.7% (88/150) of the HCC cases and 74.3% (101/136) of controls. HBV mutants were observed in 44.3% of HCC cases and 43.2% of controls. HBV/D was prevalent amongst the patients and controls, followed by HBV/A. The prevalence of the TT1504 mutation in the X gene, the V1753 and T1762/A1764 mutations in the BCP region, and G1914 mutation in the core gene were significantly higher in the HCC group than in the non‐HCC group. Multivariate analyses showed that the TT1504, V1753, A1762T/G1764A, and the G1914 mutations and the patient's age, sex, and HBeAg status increased the risk of HCC development significantly. Also, patients with HCC had lower levels of serum albumin, viral load, and platelet counts but higher values of alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, bilirubin, and Alpha feto‐protein than those of controls (P < 0.001 for all comparisons). HBV/D was the predominant genotype associated with HCC cases seen in India. The presence of different types of HBV mutations, age, sex, HBeAg status, and viral load was found to increase significantly the risk of HCC development in India. J. Med. Virol. 82: 1115–1125, 2010. © 2010 Wiley‐Liss, Inc.     

Prevalence and social correlates of postnatal depression in a low income country

Summary Background: Postnatal depression is an important public health problem worldwide. Recent evidence suggests that rates may be relatively higher in developing countries. We aimed to explore the prevalence of postnatal depression and its association with social support and other risk factors in a sample of Pakistani women. Methods: Population-based survey of 149 women at 12 weeks postnatal using the Edinburgh Postnatal Depression Scale (EPDS), Multidimensional Scale of Perceived Social Support (MSPSS) and Personal Information Questionnaire (PIQ). Results: Thirty six percent women scored ≥12 on EPDS. High depression score was associated with lower social support, increased stressful life events in the preceding year and higher levels of psychological distress in the antenatal period. Conclusions: There is a high prevalence of postnatal depression in Pakistani women. Early interventions should be developed that target the antenatal period and strengthen social support networks in women at risk.