1,523 research outputs found

    Molecular Studies in Horses with SRY-Positive XY Sex Reversal

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    Sex determination in mammals is regulated by the sex-determining region on the Y chromosome (SRY); the presence of SRY activates the male developmental pathway and suppresses the gene network necessary for female gonad development. Mutations in sex determination genes lead to various abnormal sexual phenotypes, including sex reversal syndrome in which the genetic and phenotypic sex do not match. Sex reversal syndrome has been reported in humans, mouse, and several domestic species. In horses, SRY-negative XY sex reversal syndrome has been well described and is caused by deletions on the Y chromosome. However, the molecular causes of the SRY-positive condition in horses and other mammals are not known. This research investigated five horses affected with SRY-positive XY sex reversal syndrome. Sequencing of the coding exon region of the SRY gene in the five cases showed 99-100% alignment with the sequences of normal males. Genotyping of two closely related individuals with 46 normal male controls on an equine SNP50 Beadchip identified two statistically significant SNPs in a ~16 Mb region on the long arm of horse chromosome 3 (ECA3q). The region was analyzed using Gene Ontology (GO) and Gene Relationships Across Implicated Loci (GRAIL) to select functionally relevant candidate genes for sequencing. Further analysis of the entire horse genome was done through array comparative genomic hybridization (aCGH), which investigated possible structural rearrangements, such as copy number variants (CNVs). Deletions of olfactory receptor genes were detected on multiple chromosomes and confirmed through quantitative real-time PCR (qPCR). A homozygous deletion on ECA29 in a region containing genes of the aldo-keto reductase gene family, known to play a role in interconverting sex hormones between active forms and inactive forms, was discovered in two sex reversed animals. The findings were confirmed through qPCR and fluorescence in situ hybridization (FISH), and experiments to define the specific breakpoints of the deletion through PCR have been initiated. This research represents the first systematic search in the horse genome for mutations and CNVs related to sex determination. The findings contribute to better understanding of the molecular mechanisms of sex determination in horses and other mammals, including humans

    Dental adhesive microtensile bond strength following a biofilm-based in vitro aging model

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    Laboratory tests are routinely used to test bonding properties of dental adhesives. Various aging methods that simulate the oral environment are used to complement these tests for assessment of adhesive bond durability. However, most of these methods challenge hydrolytic and mechanical stability of the adhesive- enamel/dentin interface, and not the biostability of dental adhesives. Objective: To compare resin-dentin microtensile bond strength (Ī¼TBS) after a 15-day Streptococcus mutans (SM) or Streptococcus sobrinus (SS) bacterial exposure to the 6-month water storage (WS) ISO 11405 type 3 test. Methodology: A total of 31 molars were flattened and their exposed dentin was restored with Optibond-FL adhesive system and Z-100 dental composite. Each restored molar was sectioned and trimmed into four dumbbell-shaped specimens, and randomly distributed based on the following aging conditions: A) 6 months of WS (n=31), B) 5.5 months of WS + 15 days of a SM-biofilm challenge (n=31), C) 15 days of a SM-biofilm challenge (n=31) and D) 15 days of a SS-biofilm challenge (n=31). Ī¼TBS were determined and the failure modes were classified using light microscopy. Results: Statistical analyses showed that each type of aging condition affected Ī¼TBS (p<0.0001). For Group A (49.7Ā±15.5MPa), the mean Ī¼TBS was significantly greater than in Groups B (19.3Ā±6.3MPa), C (19.9Ā±5.9MPa) and D (23.6Ā±7.9MPa). For Group D, the mean Ī¼TBS was also significantly greater than for Groups B and C, but no difference was observed between Groups B and C. Conclusion: A Streptococcus mutans- or Streptococcus sobrinus-based biofilm challenge for 15 days resulted in a significantly lower Ī¼TBS than did the ISO 11405 recommended 6 months of water storage. This type of biofilm-based aging model seems to be a practical method for testing biostability of resin-dentin bonding

    Gender Differences in Self-Reported Symptoms of Depression among Patients with Acute Coronary Syndrome

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    This study examined the prevalence of self-reported depressive symptoms and the self reported somatic depressive symptoms as measured by the Beck Depression Inventory-II (BDI-II) among patients hospitalized for acute coronary syndrome (ACS), and explored the impact of gender on both. A convenience sample of 789 adults (248 women and 541 men) was recruited for the study during hospital admission for ACS and participants were screened for self-reported depressive symptoms. BDI-II scores of ā‰„14 indicate a moderate level of depressive symptoms and this cut-off score was used to categorize patients into depressed and non-depressed groups. Pearson chi-square tests for independence (categorical variables) and t tests for independent samples (continuous variables) were used for gender comparisons. Results showed that depressive symptoms during ACS episodes were different between women and men. Women reported greater overall depressive symptoms (BDI-II mean = 11.89, S.D. = 9.68) than men (BDI-II mean = 9.00, S.D. = 7.93) (P < 0.000). Significantly more women (7.66%) were identified positive for somatic depressive symptoms (sleep and appetite disturbances and fatigue) than men (2.22%) (P = 0.0003). Findings support that there are gender differences in depressive symptoms experienced by patients hospitalized for ACS. Somatic symptoms of depression may be important indicators of depression especially among female ACS patients

    A solid-state switch containing an electrochemically switchable bistable poly[n]rotaxane

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    Electrochemically switchable bistable main-chain poly[n]rotaxanes have been synthesised using a threading-followed-by-stoppering approach and were incorporated into solid-state, molecular switch tunnel junction devices. In contrast to single-station poly[n]rotaxanes of similar structure, the bistable polymers do not fold into compact conformations held together by donorā€“acceptor interactions between alternating stacked p-electron rich and p-electron deficient aromatic systems. Films of the poly[n]rotaxane were incorporated into the devices by spin-coating, and their thickness was easily controlled. The switching functionality was characterised both (1) in solution by cyclic voltammetry and (2) in devices containing either two metal electrodes or one metal and one silicon electrode. Devices with one silicon electrode displayed hysteretic responses with applied voltage, allowing the devices to be switched between two conductance states, whereas devices containing two metal electrodes did not exhibit switching behaviour. The electrochemically switchable bistable poly[n]rotaxanes offer significant advantages in synthetic efficiency and ease of device fabrication as compared to bistable small-molecule [2]rotaxanes

    Hybrid silicon evanescent approach to optical interconnects

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    We discuss the recently developed hybrid silicon evanescent platform (HSEP), and its application as a promising candidate for optical interconnects in silicon. A number of key discrete components and a wafer-scale integration process are reviewed. The motivation behind this work is to realize silicon-based photonic integrated circuits possessing unique advantages of IIIā€“V materials and silicon-on-insulator waveguides simultaneously through a complementary metal-oxide semiconductor fabrication process. Electrically pumped hybrid silicon distributed feedback and distributed Bragg reflector lasers with integrated hybrid silicon photodetectors are demonstrated coupled to SOI waveguides, serving as the reliable on-chip single-frequency light sources. For the external signal processing, Machā€“Zehnder interferometer modulators are demonstrated, showing a resistance-capacitance-limited, 3Ā dB electrical bandwidth up to 8 GHz and a modulation efficiency of 1.5Ā VĀ mm. The successful implementation of quantum well intermixing technique opens up the possibility to realize multiple IIIā€“V bandgaps in this platform. Sampled grating DBR devices integrated with electroabsorption modulators (EAM) are fabricated, where the bandgaps in gain, mirror, and EAM regions are 1520, 1440 and 1480Ā nm, respectively. The high-temperature operation characteristics of the HSEP are studied experimentally and theoretically. An overall characteristic temperature (T 0) of 51Ā°C, an above threshold characteristic temperature (T 1) of 100Ā°C, and a thermal impedance (Z T ) of 41.8Ā°C/W, which agrees with the theoretical prediction of 43.5Ā°C/W, are extracted from the Fabryā€“Perot devices. Scaling this platform to larger dimensions is demonstrated up to 150Ā mm wafer diameter. A vertical outgassing channel design is developed to accomplish high-quality IIIā€“V epitaxial transfer to silicon in a timely and dimension-independent fashion

    Synthesis of a series of novel 3,9-disubstituted phenanthrenes as analogues of known <i>N</i>-methyl-D-aspartate receptor allosteric modulators

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    9-Substituted phenanthrene-3-carboxylic acids have been reported to have allosteric modulatory activity at the NMDA receptor. This receptor is activated by the excitatory neurotransmitter L-glutamate and has been implicated in a range of neurological disorders such as schizophrenia, epilepsy and chronic pain and neurodegenerative disorders such as Alzheimerā€™s disease. Herein, the convenient synthesis of a wide range of novel 3,9-disubstituted phenanthrene derivatives starting from a few common intermediates is described. These new phenanthrene derivatives will help to clarify the structural requirements for allosteric modulation of the NMDA receptor

    Aspirin and other non-steroidal anti-inflammatory drugs and depression, anxiety, and stress-related disorders following a cancer diagnosis: a nationwide register-based cohort study

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    Publisher's version (Ćŗtgefin grein)Background: Cancer patients have a highly increased risk of psychiatric disorders following diagnosis, compared with cancer-free individuals. Inflammation is involved in the development of both cancer and psychiatric disorders. The role of non-steroidal anti-inflammatory drugs (NSAIDs) in the subsequent risk of psychiatric disorders after cancer diagnosis is however unknown. Methods: We performed a cohort study of all patients diagnosed with a first primary malignancy between July 2006 and December 2013 in Sweden. Cox proportional hazards models were used to assess the association of NSAID use during the year before cancer diagnosis with the risk of depression, anxiety, and stress-related disorders during the first year after cancer diagnosis. Results: Among 316,904 patients identified, 5613 patients received a diagnosis of depression, anxiety, or stress-related disorders during the year after cancer diagnosis. Compared with no use of NSAIDs, the use of aspirin alone was associated with a lower rate of depression, anxiety, and stress-related disorders (hazard ratio [HR], 0.88; 95% confidence interval [CI], 0.81 to 0.97), whereas the use of non-aspirin NSAIDs alone was associated with a higher rate (HR, 1.24; 95% CI, 1.15 to 1.32), after adjustment for sociodemographic factors, comorbidity, indications for NSAID use, and cancer characteristics. The association of aspirin with reduced rate of depression, anxiety, and stress-related disorders was strongest for current use (HR, 0.84; 95% CI, 0.75 to 0.93), low-dose use (HR, 0.88; 95% CI, 0.80 to 0.98), long-term use (HR, 0.84; 95% CI, 0.76 to 0.94), and among patients with cardiovascular disease (HR, 0.81; 95% CI, 0.68 to 0.95) or breast cancer (HR, 0.74; 95% CI, 0.56 to 0.98). Conclusion: Pre-diagnostic use of aspirin was associated with a decreased risk of depression, anxiety, and stress-related disorders during the first year following cancer diagnosis.This study was supported by grants awarded to FF by Swedish Cancer Society (No. CAN 2017/322) and the Swedish Research Council for Health, Working Life and Welfare (No. 2017-00531), to KH by China Scholarship Council (No. 201806240005), to ES by National Health and Medical Research Council (GNT1147498) and National Breast Cancer Foundation (IIRS-20 to 025), and to AW by the National Breast Cancer Foundation (PF-15 to 014). The researchers were independent of the funding agencies. The funding bodies have no role in the design of the study or collection, analysis, and interpretation of data or in writing the manuscript. Open access funding provided by Karolinska Institute.Peer Reviewe
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