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101.
Andrzej Bartke 《Clinical Interventions in Aging》2008,3(4):659-665
Although advanced age or symptoms of aging are not among approved indications for growth hormone (GH) therapy, recombinant human GH (rhGH) and various GH-related products are aggressively promoted as anti-aging therapies. Well-controlled studies of the effects of rhGH treatment in endocrinologically normal elderly subjects report some improvements in body composition and a number of undesirable side effects in sharp contrast to major benefits of GH therapy in patients with GH deficiency. Controversies surrounding the potential utility of GH in treatment of a geriatric patient are fueled by increasing evidence linking GH and cancer and by remarkably increased lifespan of GH-resistant and GH-deficient mice. Conservation of cellular signaling mechanisms that influence aging in organisms ranging from worms to mammals suggests that at least some of the results obtained in mutant mice are applicable to the human. We suggest that the normal, physiological functions of GH in promoting growth, sexual maturation and fecundity involve significant costs in terms of aging and life expectancy. Natural decline in GH levels during aging likely contributes to concomitant alterations in body composition and vigor but also may be offering important protection from cancer and other age-associated diseases. 相似文献
102.
Digit ratio (2D:4D) does not correlate with daily 17β‐estradiol and progesterone concentrations in healthy women of reproductive age
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Andrzej Grzybowski Magdalena Zülsdorff Helmut Wilhelm Felix Tonagel 《Acta ophthalmologica. Supplement》2015,93(5):402-410
Toxic optic neuropathy (TON) is caused by the damage to the optic nerve through different toxins, including drugs, metals, organic solvents, methanol and carbon dioxide. A similar clinical picture may also be caused by nutritional deficits, including B vitamins, folic acid and proteins with sulphur‐containing amino acids. This review summarizes the present knowledge on disease‐causing factors, clinical presentation, diagnostics and treatment in TON. It discusses in detail known and hypothesized relations between drugs, including tuberculostatic drugs, antimicrobial agents, antiepileptic drugs, antiarrhythmic drugs, disulfiram, halogenated hydroquinolones, antimetabolites, tamoxifen and phosphodiesterase type 5 inhibitors and optic neuropathy. 相似文献
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Justyna Kalinowska-Tucik Jakub Staro Anna Krawczuk Stefan Mordalski Dawid Warszycki Grzegorz Sataa Adam S. Hogendorf Andrzej J. Bojarski 《RSC advances》2018,8(33):18672
The development of compounds with enhanced activity and selectivity by a conserved spatial orientation of the pharmacophore elements has a long history in medicinal chemistry. Rigidified compounds are an example of this concept. However, the intramolecular interactions were seldom used as a basis for conformational restraints. Here, we show the weak intramolecular interactions that contribute to the relatively well-conserved geometry of N1-arylsulfonyl indole derivatives. The structure analysis along with quantum mechanics calculations revealed a crucial impact of the sulfonyl group on the compound geometry. The weak intramolecular C–H⋯O interaction stabilizes the mutual "facing" orientation of two aromatic fragments. These findings extend the pharmacological interpretation of the sulfonyl group role from the double hydrogen bond acceptor to the conformational scaffold based on intramolecular forces. This feature has, to date, been omitted in in silico drug discovery. Our results should increase the awareness of researchers to consider the conformational preference when designing new compounds or improving computational methods.The impact of weak intramolecular C–H⋯O interactions on the conformational stability of bis-arylsulfones is discussed, suggesting different role of sulfonyl group in the ligand – 5HT6 receptor interaction. 相似文献
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BACKGROUND: Modern therapy of acute myocardial infarction (AMI) is aimed at rapid and persisting restoration of blood flow in an infarct-related artery (IRA). However, in some patients myocardial reperfusion is not achieved in spite of effective IRA recanalisation. Myocardial Blush Grade (MBG) is one of the angiographic markers useful for the detection of this phenomenon. AIM: To assess the prognostic value of MBG in patients with anterior AMI treated with primary angioplasty. METHODS: The study group consisted of 104 patients (74 males, 30 females, mean age 62+/-13 years) treated with primary angioplasty due to anterior ST-segment elevation AMI. MBG was assessed after the procedure. The mortality and major cardiovascular event (MACE) rates were analysed one and six months after AMI. RESULTS: Patients with preserved myocardial reperfusion following angioplasty (MBG 2-3, n=64 (61.5%)) had a trend towards lower one-month mortality and significantly reduced six-month mortality compared with 40 (38.5%) patients with an impaired (MBG 0-1) myocardial reperfusion (3% vs 12.5%, NS; and 6.25% vs 20%, p<0.05, respectively). The rate of MACE was significantly lower in patients with rather than without reperfusion both after one and six months of follow-up (9.4% vs 27.5%, p=0.027 and 12.5% vs 42.5%, p<0.001, respectively). Compared with patients with a high MBG score, patients with altered reperfusion more frequently had diabetes (30% vs 12.5%, p=0.04), hypertension (67.5% vs 45%, p=0.043), longer time from the onset of symptoms to balloon inflation (355.9+/-199 min vs 215.5+/-113 min, p<0.001) and lower left ventricular ejection fraction, measured 3 days after AMI (43.3%+/-8 vs 47.4%+/-9, p=0.02). CONCLUSIONS: MBG has a significant prognostic value in patients with anterior AMI treated with primary angioplasty. Diabetes, hypertension and long delay of treatment are associated with the impairment of myocardial reperfusion. 相似文献
109.
Subacute stent thrombosis following coronary angioplasty: incidence and risk factors 总被引:1,自引:0,他引:1
Lesiak M Grajek S Pyda M Skorupski W Mitkowski P Grygier M Prech M Paradowski S Cieśliński A 《Kardiologia polska》2003,59(11):408-416
BACKGROUND: Subacute stent thrombosis was a significant complication in the early years of coronary stenting, often leading to myocardial infarction, need for urgent surgery or even death. The introduction of intracoronary ultrasound enabled the identification and proper treatment of the main causes of stent thrombosis, reducing the rate of this complication to 1%. AIM: To identify risk factors of subacute stent thrombosis. METHODS: Data concerning 845 procedures with a single stent implantation in patients with stable or unstable angina, undergoing this procedure between 1998 and 2000, were analysed. RESULTS: Subacute stent thrombosis occurred in 13 (1.54%) patients. Risk factors for this complication included urgent procedures (so-called bailout stenting), improper pre-treatment with drugs ("ad hoc" procedures), dissection uncovered by stent, and poor final result of procedure (higher degree of residual stenosis). The majority of these patients developed myocardial infarction in spite of the fact that the patency of stented vessel was quickly achieved in all but one patient. CONCLUSIONS: Urgent stenting, improper drug pre-treatment and suboptimal result of the procedure are the risk factors of subacute stent thrombosis. 相似文献
110.