145 research outputs found

    Effect of Base-Pairing Partner on the Thermodynamic Stability of the Diastereomeric Spiroiminodihydantoin Lesion

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    Oxidation of guanine by reactive oxygen species and high valent metals produces damaging DNA base lesions like 8-oxo-7,8-dihydroguanine (8-oxoG). 8-oxoG can be further oxidized to form the spiroiminodihydantoin (Sp) lesion, which is even more mutagenic. DNA polymerases preferentially incorporate purines opposite the Sp lesion, and DNA glycosylases excise the Sp lesion from the duplex, although the rate of repair is different for the two Sp diastereomers. To further understand the biological processing of the Sp lesion, differential scanning calorimetry (DSC) studies were performed on a series of 15-mer DNA duplexes. The thermal and thermodynamic stability of each of the Sp diastereomers paired to the four standard DNA bases was investigated. It was found that, regardless of the base-pairing partner, the Sp lesion was always highly destabilizing in terms of DNA melting temperature, enthalpic stability, and overall duplex free energy. We found no significant differences between the two Sp diastereomers, but changing the base pairing partner of the Sp lesion produced slight differences in stability. Specifically, duplexes with Sp:C pairings were always the most destabilized, whereas pairing the Sp lesion with a purine base modestly increased stability. Overall, these results suggest that although the stability of the Sp diastereomers cannot explain the differences in the rates of repair by DNA glycosylases, the most stable base pairing partners do correspond with the nucleotide preference of DNA polymerases

    Fertility, Living Arrangements, Care and Mobility

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    There are four main interconnecting themes around which the contributions in this book are based. This introductory chapter aims to establish the broad context for the chapters that follow by discussing each of the themes. It does so by setting these themes within the overarching demographic challenge of the twenty-first century – demographic ageing. Each chapter is introduced in the context of the specific theme to which it primarily relates and there is a summary of the data sets used by the contributors to illustrate the wide range of cross-sectional and longitudinal data analysed

    Chronic Activation of Corticotropin-Releasing Factor Type 2 Receptors Reveals a Key Role for 5-HT1A Receptor Responsiveness in Mediating Behavioral and Serotonergic Responses to Stressful Challenge

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    BackgroundThe corticotropin-releasing factor type 2 receptor (CRFR2) is suggested to play an important role in aiding recovery from acute stress, but any chronic effects of CRFR2 activation are unknown. CRFR2 in the midbrain raphé nuclei modulate serotonergic activity of this key source of serotonin (5-HT) forebrain innervation.MethodsTransgenic mice overexpressing the highly specific CRFR2 ligand urocortin 3 (UCN3OE) were analyzed for stress-related behaviors and hypothalamic-pituitary-adrenal axis responses. Responses to 5-HT receptor agonist challenge were assessed by local cerebral glucose utilization, while 5-HT and 5-hydroxyindoleacetic acid content were quantified in limbic brain regions.ResultsMice overexpressing urocortin 3 exhibited increased stress-related behaviors under basal conditions and impaired retention of spatial memory compared with control mice. Following acute stress, unlike control mice, they exhibited no further increase in these stress-related behaviors and showed an attenuated adrenocorticotropic hormone response. 5-HT and 5-hydroxyindoleacetic acid content of limbic nuclei were differentially regulated by stress in UCN3OE mice as compared with control mice. Responses to 5-HT type 1A receptor challenge were significantly and specifically reduced in UCN3OE mice. The distribution pattern of local cerebral glucose utilization and 5-HT type 1A receptor messenger RNA expression levels suggested this effect was mediated in the raphé nuclei.ConclusionsChronic activation of CRFR2 promotes an anxiety-like state, yet with attenuated behavioral and hypothalamic-pituitary-adrenal axis responses to stress. This is reminiscent of stress-related atypical psychiatric syndromes such as posttraumatic stress disorder, chronic fatigue, and chronic pain states. This new understanding indicates CRFR2 antagonism as a potential novel therapeutic target for such disorders

    BENO KOTRULJEVIĆ - UTEMELJITELJ HRVATSKE EKONOMSKE MISLI

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    Beno Kotruljević, bogati dubrovački trgovac iz prve polovine 15. stoljeća, utemeljitelj je hrvatske gospodarske misli i jedan od pionira ranog merkantilizma. Pored Juja Križanića je najznačajnije ime hrvatske ekonomske literature. Nastojeći dokazati značaj trgovine kao gospodarske djelatnosti, opisao je trgovačku praksu svog vremena i dao vlastita promišljanja o nekim bitnim pitanjima vezanim za trgovinu. U odnosu na raniju kanonističko-skolastičku gospodarsku misao, učinio je teorijske pomake u problematici trgovine, kamate, kredita i cijena. Iako je njegov rad "O trgovini i savršenom trgovcu" dosta istražen, uvijek je moguće naći u njemu nove doprinose. Ovaj rad pokušava otkriti nove spoznaje o istaknutom Dubrovčaninu

    Maternal Weight Loss during Exclusive Breastfeeding Is Associated with Reduced Weight and Length Gain in Daughters of HIV-Infected Malawian Women

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    Maternal weight loss during exclusive breastfeeding may influence the growth of exclusively breast-fed infants through impaired quality or quantity of breast milk. This study evaluated how maternal weight loss from 2 to 24 wk postpartum was related to infant weight and length gain in 1309 lactating HIV-infected mothers and their exclusively breast-fed infants. Malawian mother-infant pairs in the Breastfeeding, Antiretrovirals, and Nutrition Study were randomized with a 2 × 3 factorial design to a 2-arm nutritional intervention with a lipid-based nutrient supplement (LNS), meeting nutritional needs of lactation, or no LNS and a 3-arm antiretroviral (ARV) intervention (maternal, infant, or no ARV regimen). Linear regression models were used to relate maternal weight loss (weight loss vs. no weight loss) to infant weight and length gain from birth to 24 mo, stratifying by gender and controlling for maternal BMI at 2 wk (mean ± SD: 23.2 ± 3.0 kg/m2) and interacting maternal BMI with weight loss. In adjusted models, compared with daughters of women who did not lose weight, length and weight gain were lower in daughters whose mothers had a lower BMI at 2 wk postpartum coupled with the weight loss. For example, among mothers with an initial BMI of 18 kg/m2, daughters of those who lost weight gained less weight [β = −0.29 kg (95% CI: −0.53, −0.06)] and length [β = −0.88 cm (95% CI: −1.52, −0.23)] from birth to 24 wk than daughters of those who gained weight. Though effects were only observed in girls, suggesting possible gender differences in suckling and feeding behavior, these findings indicate that maternal weight loss with low energy reserves represents a risk factor for poor infant growth outcomes

    Antiretroviral Treatment Is Associated With Iron Deficiency in HIV-Infected Malawian Women That Is Mitigated With Supplementation, but Is Not Associated With Infant Iron Deficiency During 24 Weeks of Exclusive Breastfeeding

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    In resource-limited settings without safe alternatives to breastfeeding, the WHO recommends exclusive breastfeeding and antiretroviral (ARV) prophylaxis. Given the high prevalence of anemia among HIV-infected women, mothers and their infants (via fetal iron accretion) may be at risk of iron deficiency. We assessed the effects of maternal micronutrient-fortified lipid-based nutrient supplements (LNS) and maternal ARV treatment or infant ARV prophylaxis on maternal and infant iron status during exclusive breastfeeding from birth to 24 weeks

    Genomic and molecular analyses identify molecular subtypes of pancreatic cancer recurrence

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    Pancreatic cancer (PC) remains a highly lethal malignancy, and most patients with localized disease that undergo surgical resection still succumb to recurrent disease. Pattern of recurrence after pancreatectomy is heterogenous, with some studies illustrating that site of recurrence can be associated with prognosis.1 Another study suggested that tumors that develop local and distant recurrence can be regarded as a homogenous disease with similar outcomes.2 Here we investigate novel molecular determinants of recurrence pattern after pancreatectomy for PC

    Ulcerative colitis and irritable bowel patients exhibit distinct abnormalities of the gut microbiota

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    <p>Abstract</p> <p>Background</p> <p>Previous studies suggest a link between gut microbiota and the development of ulcerative colitis (UC) and irritable bowel syndrome (IBS). Our aim was to investigate any quantitative differences in faecal bacterial compositions in UC and IBS patients compared to healthy controls, and to identify individual bacterial species that contribute to these differences.</p> <p>Methods</p> <p>Faecal microbiota of 13 UC patients, 11 IBS patients and 22 healthy volunteers were analysed by PCR-Denaturing Gradient Gel Electrophoresis (DGGE) using universal and Bacteroides specific primers. The data obtained were normalized using in-house developed statistical method and interrogated by multivariate approaches. The differentiated bands were excised and identified by sequencing the V3 region of the 16S rRNA genes.</p> <p>Results</p> <p>Band profiles revealed that number of predominant faecal bacteria were significantly different between UC, IBS and control group (p < 10<sup>-4</sup>). By assessing the mean band numbers in UC (37 ± 5) and IBS (39 ± 6), compared to the controls (45 ± 3), a significant decrease in bacterial species is suggested (p = 0.01). There were no significant differences between IBS and UC. Biodiversity of the bacterial species was significantly lower in UC (μ = 2.94, σ = 0.29) and IBS patients (μ = 2.90, σ = 0.38) than controls (μ = 3.25, σ = 0.16; p = 0.01). Moreover, similarity indices revealed greater biological variability of predominant bacteria in UC and IBS compared to the controls (median Dice coefficients 76.1% (IQR 70.9 - 83.1), 73.8% (IQR 67.0 - 77.5) and 82.9% (IQR 79.1 - 86.7) respectively). DNA sequencing of discriminating bands suggest that the presence of <it>Bacteroides vulgatus, B. ovatus, B. uniformis</it>, and <it>Parabacteroides sp</it>. in healthy volunteers distinguishes them from IBS and UC patients. DGGE profiles of Bacteroides species revealed a decrease of Bacteroides community in UC relative to IBS and controls.</p> <p>Conclusion</p> <p>Molecular profiling of faecal bacteria revealed abnormalities of intestinal microbiota in UC and IBS patients, while different patterns of Bacteroides species loss in particular, were associated with UC and IBS.</p
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