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81.
Aromatic hydrocarbon (AH) effects are mediated by binding of the AH receptor and its heterodimeric partner aromatic hydrocarbon nuclear translocator to specific response elements on DNA (AHREs). CYP1A2 expression is induced by AHs, yet AHREs have been identified in CYP1A2 genes of only two species and their functional role assessed only in the human gene. There have been few analyses of CYP1A2 gene regulation in nonhepatic cells. To gain further insight into CYP1A2 regulation, we cloned the initial 1.2 kilobases (kb) of the guinea pig CYP1A2 gene 5'-flanking region and characterized CYP1A2 expression in guinea pig colon adenocarcinoma cells (GPC16). Two putative AHRE sites were identified (-830 and -575 bp). They are considerably more proximal than the functional AHRE found in the human CYP1A2 gene (-2.5 kb). GPC16 cells expressed CYP1A2 after treatment with AH, enabling characterization of the putative AHRE sites in a homologous cell line. Double-stranded oligonucleotide probes, corresponding to each putative AHRE, bound in an AH-induced and specific manner to nuclear proteins prepared from GPC16 cells. In transfection analyses, only the distal site mediated AH-induced reporter gene activity. Mutation of this site suppressed AH-induced activity, supporting the concept that it is involved in AH-mediated induction of CYP1A2. However, the low level of AH-induction by the wild type suggests that other factors modulate AH-response by the CYP1A2 gene.  相似文献   
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Purpose. In women with breast cancer, knowledge of the local/regional extent of the tumor is essential for staging, treatment planning, monitoring response to therapy, and follow-up. Positron emission tomography (PET) is an important imaging test which can detect tumor at multiple sites in women with breast cancer. We compared the ability of PET to provide a comprehensive view of the local/regional extent of tumor in women with stage I, II and stage III, IV breast cancer. Materials and methods. Forty-six women with breast cancer underwent PET using 18F-FDG. 18FDG uptake in the breast primary tumor, associated skin, axillary and internal mammary lymph nodes, and the contralateral breast was determined qualitatively, and correlated with histologic, clinical and radiographic findings. Results. Twenty-four patients were premenopausal and 22 were postmenopausal, with the following distribution according to clinical stage: stage I – 2 patients, stage II – 16, stage III – 16, stage IV – 12 patients. Among stage I, II patients, the sensitivity for detection of the primary tumor was 83.3%, and for detection of axillary lymph node metastases was 42.9%. 18FDG-PET was negative for the breast skin, contralateral breast, and internal mammary lymph nodes in all stage I, II patients, in agreement with clinical and radiographic findings. Among 28 stage III, IV patients, the sensitivity of 18FDG-PET for detection of the primary tumor was 90.5%, and for detection of axillary lymph node metastases 83.3%. Fourteen patients had clinically advanced changes in the skin, and the sensitivity of PET for detection of skin changes was 76.9%. 18FDG-PET was positive in the internal mammary lymph nodes in 25.0%, and negative in the contralateral breast in all patients with stage III, IV breast cancer. 18FDG-PET was studied in 10 patients following neoadjuvant chemotherapy, and showed a strong correlation with clinical response, and with clinical and pathological findings post-treatment at multiple local/regional sites. Conclusion. 18FDG-PET can provide a comprehensive image of local/regional tumor in women with breast cancer. 18FDG-PET may play a greater role in women with stage III, IV breast cancer because of increased sensitivity and the increased involvement of multiple local/regional sites with tumor.  相似文献   
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Cardiopulmonary complications remain a leading cause of morbidity and mortality in sickle cell disease (SCD). The overall goals of this study were to evaluate the relationship between left ventricular hypertrophy (LVH) and laboratory markers of hemolysis and determine the association between LVH and SCD-specific therapies (hydroxyurea and chronic red cell transfusion). Data from the DISPLACE (Dissemination and Implementation of Stroke Prevention Looking at the Care Environment) study cohort was used. LVH was defined based on the left ventricular mass indexed to the body surface area as left ventricular mass index >103.0 g/m2 for males and >84.2 g/m2 for females. There were 1,409 children included in the analysis and 20.3% had LVH. Results of multivariable analysis of LVH showed baseline hemoglobin levels were associated with the lower odds of having LVH (odds ratio [OR]: 0.71, 95% confidence interval [CI]: 0.60– 0.84). The odds of LVH increases for every 1-year increase in age (OR: 1.07, 95% CI: 1.02-1.13). Similarly, the odds of LVH were lower among males than females (OR: 0.59, 95% CI: 0.38-0.93). The odds of LVH were higher among those on hydroxyurea compared to no therapy (OR: 1.83, 95% CI: 1.41–2.37). Overall results of the study showed that LVH occurs early in children with SCD and the risk increases with increasing age and with lower hemoglobin. Further, we found higher use of hydroxyurea among those with LVH, suggesting that the need for hydroxyurea conveys a risk of cardiovascular remodeling.  相似文献   
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ObjectiveThis study aimed to examine the effects of low-quality employment trajectories on severe common mental disorders (CMD) according to Swedish and foreign background.MethodsIn this longitudinal study based on Swedish population registries (N=2 703 687), low- and high-quality employment trajectories were the main exposures observed across five years (2005–2009), with severe CMD as outcome variable (2010–2017). Adjusted hazard ratios (HR) were calculated by means of Cox regression models and stratified according to Swedish and foreign background [first-generation (i) EU migrants, (ii) non-EU migrants, (iii) second-generation migrants, (iv) Swedish-born of Swedish background] and sex. The reference group was Swedish-born of Swedish background in a constant high-quality employment trajectory.ResultsSecond-generation migrants had an increased risk of CMD compared to Swedish-born of Swedish background when following low-quality employment trajectories [eg, male in constant low-quality HR 1.54, 95% confidence interval (CI) 1.41–1.68]. Female migrant workers, especially first-generation from non-EU countries in low-quality employment trajectories (eg, constant low-quality HR 1.66, 95% CI 1.46–1.88), had a higher risk of CMD compared to female Swedish-born of Swedish background. The risk for CMD according to employment trajectories showed little differences between first- and second-generation migrants.ConclusionLow-quality employment trajectories appear to be determinants of risk for CMD in association with Swedish or foreign background of origin and sex. Our study shows a higher risk for severe CMD in second-generation and non-EU migrant compared to Swedish-born of Swedish background in constant low-quality employment. Further qualitative research is recommended to understand the mechanism behind the differential mental health impact of low-quality employment trajectories according to foreign background.  相似文献   
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Women with polycystic ovary syndrome (PCOS) frequently experience decreased sexual arousal, desire, and sexual satisfaction. While the hypothalamus is known to regulate sexual behavior, the specific neuronal pathways affected in patients with PCOS are not known. To dissect the underlying neural circuitry, we capitalized on a robust preclinical animal model that reliably recapitulates all cardinal PCOS features. We discovered that female mice prenatally treated with anti-Müllerian hormone (PAMH) display impaired sexual behavior and sexual partner preference over the reproductive age. Blunted female sexual behavior was associated with increased sexual rejection and independent of sex steroid hormone status. Structurally, sexual dysfunction was associated with a substantial loss of neuronal nitric oxide synthase (nNOS)-expressing neurons in the ventromedial nucleus of the hypothalamus (VMH) and other areas of hypothalamic nuclei involved in social behaviors. Using in vivo chemogenetic manipulation, we show that nNOSVMH neurons are required for the display of normal sexual behavior in female mice and that pharmacological replenishment of nitric oxide restores normal sexual performance in PAMH mice. Our data provide a framework to investigate facets of hypothalamic nNOS neuron biology with implications for sexual disturbances in PCOS.

Polycystic ovary syndrome (PCOS) is a highly prevalent disease affecting 5 to 18% of women of reproductive age worldwide (1, 2). PCOS is diagnosed upon the presence of at least two out of three prime features: high circulating levels of androgens (hyperandrogenism), menstrual irregularities (oligo-anovulation), and polycystic-like ovarian morphology (2, 3). Beyond its implications leading to female infertility, the disease is associated with several metabolic disruptions, cardiovascular diseases, and psychosocial disorders (4). Among these neurological implications, it has become clear that approximately 30% or more of patients with PCOS experience sexual dysfunctions, with clinical studies reporting a high risk of low sexual arousal, desire, and satisfaction and impaired lubrication and orgasm (59). These symptoms allude to disturbances in brain circuits controlling sexual function in the context of PCOS.Neural circuits driving female sexual behaviors are conserved among vertebrate species operating under the influence of sex steroid hormone modulation, which is paramount for partner interaction, receptivity, and sexual performance (10, 11). Indeed, gonadal sex hormones are implicated in shaping circuit architecture in the hypothalamus during development and activating these neonatally programmed circuits over reproductive adult life in many species (1216). The hypothalamus integrates sensorial stimuli and autonomic arousal from endogenous sex drive cues (e.g., estrous phase, energy status, hormone milieu, genital stimulation) to convey this information to other brain areas and peripheral nerves (10, 17). The ventromedial nucleus of the hypothalamus (VMH) is considered the hub of specialized neurons, with intrinsic properties driving different components of sexual behavior (1821). The VMH harbors neurons expressing neuronal nitric oxide synthase (nNOS), the enzyme responsible for the production of nitric oxide (NO), a key gaseous neurotransmitter that stimulates female sexual behavior (22, 23) and communicates with other circuits within the social brain (24, 25). Despite current advances unraveling novel pathways in the female sexual brain with specific behavioral responses, there is a clear lack of knowledge on how disturbances in these circuits may participate in sexual dysfunctions affecting one-third of women with PCOS.Growing evidence indicates that androgen excess in utero induces a developmental reprogramming of the female fetal brain toward the manifestation of PCOS traits later in life (2629). Some studies have suggested that the clinical signs of hyperandrogenism have detrimental sexual effects (5), indicating a negative correlation between androgen levels and sexual function in PCOS. In recent years, it has been proposed that prenatal anti-Müllerian hormone excess may trigger gestational hyperandrogenism via the inhibition of placental aromatase (29, 30) and that women with PCOS display higher circulating levels of androgens and AMH during pregnancy as compared to healthy women (29, 31). Prenatal AMH-treated mice (PAMH) reliably recapitulate all the mouse equivalents of the PCOS Rotterdam criteria (29, 32) and are thus a preclinical model to mimic the human PCOS condition. PAMH female mice also display pronounced neuroendocrine dysfunction leading to exacerbated luteinizing hormone (LH) secretion (29), as in women with PCOS (33), denoting the presence of prenatally reprogrammed defects within the gonadotropin-releasing hormone (GnRH) neuronal network. Thus, prenatal AMH excess–mediated disruptions in the female brain may be key to understanding the pathophysiology of PCOS.Here, we investigated whether prenatal AMH excess could underpin defects in sex circuits promoting sexual dysfunction in PCOS-like female mice. We uncovered a profound decrease of nNOS and progesterone receptor (PR) expression in the VMH. These anatomical changes were also associated with significant impairment of sexual receptivity in PCOS-like female mice. Nevertheless, normal sexual function in PAMH female mice was restored to control levels upon peripheral injection of NO donor. Performing a series of acute functional manipulations in freely moving female mice, we showed that chemogenetic silencing of nNOSVMH neurons in control female mice recapitulates PCOS-like sexual dysfunctions. Taken together, we unveiled a brain pathway potentially underpinning the etiology of low sexual drive in PCOS while pointing to prospective therapeutic approaches to rescue normal sexual function in these women.  相似文献   
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In this report, we describe a national-scale monitoring of the SARS-CoV-2 (SC-2) variant dynamics in Israel, using multiple-time sampling of 13 wastewater treatment plants. We used a combination of inclusive and selective quantitative PCR assays that specifically identify variants A19/A20 or B.1.1.7 and tested each sample for the presence and relative viral RNA load of each variant. We show that between December 2020 and March 2021, a complete shift in the SC-2 variant circulation was observed, where the B.1.1.7 replaced the A19 in all examined test points. We further show that the normalized viral load (NVL) values and the average new cases per week reached a peak in January 2021 and then decreased gradually in almost all test points, in parallel with the progression of the national vaccination campaign, during February–March 2021. This study demonstrates the importance of monitoring SC-2 variant by using a combination of inclusive and selective PCR tests on a national scale through wastewater sampling, which is far more amendable for high-throughput monitoring compared with sequencing. This approach may be useful for real-time dynamics surveillance of current and future variants, such as the Omicron (BA.1, BA.2) and other variants.  相似文献   
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