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Dara M Cannon Masanori Ichise Denise Rollis Jacqueline M Klaver Shilpa K Gandhi Dennis S Charney Husseini K Manji Wayne C Drevets 《Neuropsychopharmacology》2007,62(8):870-877
BACKGROUND: Altered serotonergic function is thought to play a role in the pathophysiology of major depressive episodes based upon evidence from neuroimaging, pharmacological, postmortem and genetic studies. It remains unclear, however, whether depressed samples that differ with respect to having shown a unipolar versus a bipolar illness course also would show distinct patterns of abnormalities within the serotonergic system. The current study compared serotonin transporter (5-HTT) binding between unipolar-depressives (MDD), bipolar-depressives (BD) and healthy-controls (HC) to assess whether the abnormalities in 5-HTT binding recently found in depressed subjects with BD extend to depressed subjects with MDD. METHODS: The 5-HTT binding-potential (BP) measured using positron emission tomography (PET) and [(11)C]DASB was compared between unmedicated, depressed subjects with MDD (n = 18) or BD (n = 18) and HC (n = 34). RESULTS: Relative to the healthy group both MDD and BD groups showed significantly increased 5-HTT BP in the thalamus (24%, 14%, respectively), insula (15%) and striatum (12%). The unipolar-depressives had elevated 5-HTT BP relative to both BD and HC groups in the vicinity of the periaqueductal gray (PAG, 20%, 22%, respectively). The bipolar-depressives had reduced 5-HTT BP relative to both HC and MDD groups in the vicinity of the pontine raphe nuclei. Depression-severity correlated negatively with 5-HTT BP in the thalamus in MDD-subjects. CONCLUSIONS: The depressed phases of MDD and BD both were associated with elevated 5-HTT binding in the insula, thalamus and striatum, but showed distinct abnormalities in the brainstem. The latter findings conceivably could underlie differences in the patterns of illness symptoms and pharmacological sensitivity observed between MDD and BD. 相似文献
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Aim: This study was conducted to investigate the mechanism of acidic pH‐induced contraction (APIC) with regard to Ca2+ handling using isometric tension recording experiments. Results: Decreasing extracellular pH from 7.4 to 6.5 produced a marked and sustained contraction of spontaneously hypertensive rat (SHR) aorta, that was 128.7 ± 2.0% of the 64.8 mm KCl‐induced contraction. Verapamil, an inhibitor of voltage‐dependent Ca2+ channels (VDCC) significantly inhibited the APIC. In Ca2+‐deficient solution, sustained contraction induced by acidic pH was abolished completely, while a transient contraction was still observed suggesting the release of Ca2+ from intracellular site. Ryanodine (1 μm ), a ryanodine receptor blocker, and 10 μm cyclopiazonic acid (CPA; a sarco/endoplasmic reticulum Ca2+ ATPase inhibitor) abolished the transient contraction induced by acidosis. In normal Ca2+‐containing solution, ryanodine significantly decreased the rate of rise as well as maximum level of APIC. Interestingly, ryanodine and CPA showed an additive inhibitory effect with verapamil and the combined treatment of ryanodine or CPA with verapamil nearly abolished the APIC. Conclusions: It is concluded that acidic pH induces Ca2+ release from ryanodine/CPA‐sensitive store of sarcoplasmic reticulum in SHR aorta. This Ca2+ plays an important role in the facilitation of the rate of rise of APIC, as well as contributing to the sustained contraction via a mechanism which is independent of Ca2+ influx through VDCC. 相似文献
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Kaur Pervinder Makkar Amanpreet Kaur Paawan Shilpa 《Bulletin of environmental contamination and toxicology》2018,100(1):167-175
Bulletin of Environmental Contamination and Toxicology - This study shows the effect of soil type and temperature on the adsorption and desorption behaviour of pendimethalin using a batch... 相似文献
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Shilpa Rao Anita Mahadevan Tanmoy Maiti Manish Ranjan Shivayogi Durgad Shwetha Arimappamagan Arivazhagan Jitender Saini 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2016,124(12):1072-1077
Hypophysitis includes three histopathologically distinct entities – granulomatous, lymphocytic and xanthomatous forms. Etiopathogenesis and the immunological differences among these is not well characterized. This study aims to explore the immunopathogenesis of granulomatous and lymphocytic forms of hypophysitis. Demographic, clinical, endocrine function and radiological features of 33 histologically confirmed cases of hypophysitis were reviewed. Immunophenotyping of inflammatory component was performed in 13/33 cases. Visual disturbances (46%), headache (36%), polyuria/polydipsia (6%), menstrual disturbance (6%) and galactorrhoea (6%) were the frequent presenting symptoms. Endocrine abnormalities were noted in 11/18 cases evaluated (61%). Hypothyroidism was the most common endocrine abnormality (33.33%) followed by hyperprolactinaemia (22%) and hypocortisolism (16.66%). On neuroimaging, sellar mass with variable contrast enhancement was observed. On histology, granulomatous hypophysitis (GH) was more common (84.84%) than lymphocytic hypophysitis (LH) (15.15%). In GH, the infiltrate had almost equal proportions of CD3+ T cells and CD68+ histiocytes. Cytotoxic T cells (CD8+) predominated [CD4:CD8 < 1]. CD20+ B cell component ranged from <5% to 50%. Fibrosis, necrosis and giant cells accompanied GH. LH in contrast, had CD4+ T‐helper cell predominance [CD4: CD8 > 1]. CD68+ histiocytes constituted <20% and CD20+ B cells, 5–40% of the infiltrates. In conclusion, GH revealed cytotoxic T cell and histiocyte rich infiltrate in contrast to CD4+ T‐cell predominance in LH suggesting that the two forms have distinct immunological mechanisms in evolution, an autoimmune process in LH and type IV hypersensitivity response in GH. 相似文献
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Background Since the first cardiac catheterization in 1929, the procedure has continually evolved with advances in understanding, capabilities, and ease of operation. Though historically performed by cut down of the brachial artery, cardiologists soon learned that transfemoral access was both easier to perform and more efficacious with regard to patient outcome. In the last 20 years, the transradial approach has been adopted, and is being utilized with increasing frequency.
Methods We conducted a survey of literature published concerning safety, efficacy, cost-effectiveness, and global uptake of transradial catheterization with specific attention to how transradial interventions compare with transfemoral interventions.
Results This review of literature indicates that when performed by an experienced interventionalist, radial catheterization is as effective as femoral catheterization and has additional benefits of shorter length of hospital stay and reduced patient costs. Transradial access is superior to transfemoral access in some, but not all, clinical scenarios; in addition, it is an effective alternative for catheterization in patients contraindicated for transfemoral procedures. Adoption of radial access in the United States is at a faster rate than previously expected, though rate of use varies drastically worldwide.
Conclusion The transradial approach is an excellent option for carrying out cardiovascular interventions, and will be adopted by more cardiologists in the upcoming years. 相似文献