短期的脱氢表雄酮治疗增加中年男性受试者的血小板cGMP产生

目的临床和人群研究提示,脱氢表雄酮和它的硫酸盐在抗动脉粥样硬化和冠心病中起保护作用。然而,这种作用的机制仍不清楚。最近报道,硫酸脱氢表雄酮通过增加一氧化氮的生成来延缓动脉粥样硬化的形成。方法24岁的男性受试者(年龄65.4±0.7岁;范围58.2~67.6岁)经盲法安慰剂对照研究,使用脱氢表雄酮(每天50 mg睡前口服)或安慰剂2个月。2个月前和2个月后评价血小板环一磷酸鸟苷(cGMP)浓度(作为一氧化氮产生的标记)和血清中硫酸脱氢表雄酮钠、脱氢表雄酮、胰岛素样生长因子1、胰岛素、葡萄糖、雌二醇、睾酮、纤溶酶原激活物抑制剂1抗原、高半胱…     

Classification, genetic predisposition and risk factors for the development of cardiomyopathies

Cardiomyopathies are an important and diverse group of heart muscle diseases in which the heart muscle itself is structural or functional abnormal. This often results in severe heart failure accompanied by arrhythmias and/or sudden death. Clinical and morphological diversity of cardiomyopathies can reflect the broad spectrum of distinct underlying molecular causes or genetic heterogeneity. In addition, modifying genes, life style and additional factors were reported to influence onset of disease, disease progression and prognosis. The individual patient's phenotype may reflect a summation and/or interaction of the underlying mutation with other genetic or environmental factors. During the last years major advances have been made in the understanding of the molecular and genetic basis of this type of disease. Nevertheless, much more progress in the identification of underlying mutations, susceptibility genes and modifier genes is important and indispensable for the development of new etiology orientated forms of therapy.     

Carbonyl iron therapy for iron deficiency anemia

To determine if elemental carbonyl iron powder is safe and effective therapy for iron deficiency anemia, 20 nonanemic and 32 anemic volunteers were studied. Single doses of 1,000 to 10,000 mg of carbonyl iron (15 to 150 times the 65 mg of iron in the usual dose of ferrous sulfate) were tolerated by nonanemic volunteers with no evidence of toxicity and only minor gastrointestinal side effects. Anemic volunteers (menstruating women who had previously donated blood) were treated with several regimens providing 1,000 to 3,000 mg of carbonyl iron daily in one to three doses for 8 to 28 days. After 12 weeks anemia was corrected in 29 of 32 patients, and serum ferritin was greater than 12 micrograms/L in 14. Hemoglobin regeneration proceeded at a rate similar to that described for therapy with oral iron salts and parenteral iron dextran. There was no evidence of hematologic, hepatic, or renal toxicity, but mild gastrointestinal side effects occurred in a majority of anemic volunteers. Carbonyl iron is an effective, inexpensive treatment for iron deficiency anemia, is accompanied by tolerable side effects and may have an advantage over therapy with iron salts by substantially reducing or eliminating the risk of iron poisoning in children.     

Citalopram and Torsades de Pointes. A case report

Inhibitors of serotonin uptake are drugs prescribed without recognised cardiovascular risk. The authors report a case of torsades de pointes following Citalopram ingestion. In this patient, the proof of reintroduction in a hospital environment resulted in prolongation of the QT interval. Screening of patients for acquired or congenital long QT intervals is therefore necessary before starting treatment with Citalopram.     

Cannulation of the noncalcified aorta generates particles of microembolic nature: an experimental study using pig aorta

BACKGROUND AND AIM OF THE STUDY: Aortic cannulation during cardiac surgery is a potential etiological factor for perioperative stroke. Cannulae may dislodge aortic-wall calcifications. In addition, the sharp edge of the cannula-tip may shear off vessel-wall tissue, which can be expelled into the lumen. This hypothesis concerning source of emboli was tested in a noncalcified aortic perfusion model. METHODS: Pig aortas were pressurized and cannulated. Washout samples were collected before and after cannulation (n = 40). Particles were deposited onto a 10-microm filter and evaluated by microscopy and digital image analysis. RESULTS: A higher incidence of particles generated by cannulation was noted as compared to before the maneuver (p < 0.001). This increase included small (<0.1 mm, p < 0.001) and intermediate-size particles (0.1-0.5 mm, p < 0.001). Particles above 0.5 mm were few and were not associated with cannulation. CONCLUSIONS: Cannulation was a source of embolic material in the noncalcified aortic model. However, these particles were less than 0.5 mm in diameter and may contribute to neurocognitive decline after cardiac surgery.     

Mechanisms involved in the regulation of bovine pulmonary vascular tone by the 5-HT1B receptor

Background and purpose:

5-HT_1B receptors may have a role in pulmonary hypertension. Their relationship with the activity of BK_Ca, a T-type voltage-operated calcium channel (VOCC) and cyclic nucleotide-mediated relaxation was examined.

Experimental approach:

Ring segments of bovine pulmonary arteries were mounted in organ baths in modified Krebs–Henseleit buffer (37^oC) under a tension of 20 mN and gassed with 95% O₂/5% CO₂. Isometric recordings were made using Chart 5 software.

Key results:

Contractile responses to 5-HT (10 nM–300 µM) were inhibited similarly by the 5-HT_1B receptor antagonist SB216641 (100 nM) and the T-type VOCC blockers mibefradil (10 µM) and NNC550396 (10 µM) with no additive effect between SB216641 and mibefradil. Inhibition by SB216641 was prevented by the potassium channel blocker, charybdotoxin (100 nM). 5-HT_1B receptor activation and charybdotoxin produced a mibefradil-sensitive potentiation of responses to U46619. Bradykinin (0.1 nM–30 µM), sodium nitroprusside (0.01 nM–3 µM), zaprinast (1 nM–3 µM), isoprenaline (0.1 nM–10 µM) and rolipram (1 nM–3 µM) produced 50% relaxation of arteries constricted with 5-HT (1–3 µM) or U46619 (30–50 nM) in the presence of 5-HT_1B receptor activation, but full relaxation of arteries constricted with U46619, the 5-HT_2A receptor agonist 2,5 dimethoxy-4 iodoamphetamine (1 µM) or 5-HT in the presence of 5-HT_1B receptor antagonism. Enhanced relaxation of 5-HT-constricted arteries by cGMP-dependent pathways, seen in the presence of the 5-HT_1B receptor antagonist, was reversed by charybdotoxin whereas cAMP-dependent relaxation was only partly reversed by charybdotoxin.

Conclusions and implications:

5-HT_1B receptors couple to inhibition of BK_Ca, thus increasing tissue sensitivity to contractile agonists by activating a T-type VOCC and impairing cGMP-mediated relaxation. Impaired cAMP-mediated relaxation was only partly mediated by inhibition of BK_Ca.     

Prevalence of internet addiction among college students in the Indian setting: a systematic review and meta-analysis

BackgroundThe internet is an integral part of everyone’s life. College going adolescents are highly vulnerable to the misuse of the internet.AimsTo estimate the pooled prevalence of internet addiction (IA) among college students in India.MethodsLiterature databases (PubMed, Web of Science, Scopus, EMBASE, PsycINFO and Google Scholar) were searched for studies assessing IA using the Young Internet Addiction Test (Y-IAT) among adolescents from India, published in the English language up to December 2020. We included studies from 2010 to 2020 as this is the marked era of momentum in wireless internet connectivity in India. The methodological quality of each study was scored, and data were extracted from the published reports. Pooled prevalence was estimated using the fixed-effects model. Publication bias was evaluated using Egger’s test and visual inspection of the symmetry in funnel plots.ResultsFifty studies conducted in 19 states of India estimated the prevalence of IA and the overall prevalence of IA as 19.9% (95% CI: 19.3% to 20.5%) and 40.7% (95% CI: 38.7% to 42.8%) based on the Y-IAT cut-off scores of 50 and 40, respectively. The estimated prevalence of severe IA was significantly higher in the Y-IAT cut-off points of 70 than 80 (12.7% (95% CI: 11.2% to 14.3%) vs 4.6% (95% CI: 4.1% to 5.2%)). The sampling method and quality of included studies had a significant effect on the estimation of prevalence in which studies using non-probability sampling and low risk of bias (total quality score ≥7) reported lower prevalence. The overall quality of evidence was rated as ‘moderate’ based on the Grading of Recommendations Assessment, Development and Evaluation criteria.ConclusionsOur nationally representative data suggest that about 20% to 40% of college students in India are at risk for IA. There is a need for further research in the reconsideration of Y-IAT cut-off points among Indian college students.PROSPERO registration numberCRD42020219511.     

Double-blind, randomized, placebo-controlled trial of a cream containing the Stryphnodendron adstringens (Martius) Coville bark extract for suppressing terminal hair growth

Background  Excess of terminal hair can be defined as excessive hair that appears in male-like pattern in women. Some experts consider this condition as a result of an atypical relationship between levels of circulating androgens and sensitivity of androgen receptors in hair follicles to circulating androgens.
Aims  The aim of this research work was to evaluate the efficacy of a topical treatment for suppressing terminal hair growth of a cream containing 6.0% of the Stryphnodendron adstringens bark extract.
Study design and subjects  Study was randomized, double-blind and placebo-controlled. Subjects with excess of terminal hair were randomized to placebo and to the active treatment (cream with 6.0% of the extract). Evaluation was performed before and after 6 months, and subjects were photographed in each time. Clinical examination was carried out with the same physicians and in accordance with the Ferriman-Gallwey (FG) score.
Results  Benefits of the cream containing S. adstringens bark extract was observed in 60.98% ( P <  0.001) of the subjects. FG score changed from 4 to 3 in the placebo group compared to 4–2 in the active. The cream suppressed the terminal hair growth and diminished the number of terminal hair. Subjects also described the reduction of skin hyperpigmentation, folliculitis and acne. Adverse events were not verified by physicians or patients.
Conclusions  The cream with 6.0% of the S. adstringens bark extract was effective on the reduction and on the reversion of the terminal hair excess, being considered a new promissory product for such finality .     

Chondroblastoma patella presenting as a pathological fracture

A 24-year-old male presented with an inability to walk after a trivial fall. He had pain and mild swelling anterior to the right knee for the past one year. X-ray showed a transverse fracture of patella with a lytic lesion occupying most of the two halves of the patella. Fine needle aspiration cytology (FNAC) of the lytic lesion revealed a few osteoclastic giant cells and occasional osteoblasts against a hemorrhagic background. Patellectomy was performed. Histology revealed trabecular bone admixed with proliferating chondroid tissue at places admixed with myxoid and fibrous tissue with focal areas of calcification suggestive of chondroblastoma. Focal areas showed osteoclastic giant cells with areas of hemorrhage. The purpose is to present a rare tumor occurring at an unusual site which presented as pathological fracture.