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101.
Ahmed Abd El Wahab Saleh Eman Mahmoud Amin Asmaa Adel Elfallah Ahmed Mohamed Hamed 《Andrologia》2020,52(11):e13773
Among various health issues, infertility has been always considered as one of the major health problems. Idiopathic infertility is still a matter of debate since the underlying mechanisms stay obscure. Idiopathic infertility is related to expanded chance of metabolic syndrome components, obesity and increased risk of cardiovascular diseases. This study aimed to assess insulin resistance and serum levels of irisin as one of the adipokines in patients with idiopathic infertility. This study included 50 male patients aged 25–50 years old suffering from idiopathic infertility, together with 50 healthy individuals of matched age as controls. Patients showed significantly increased homeostasis model assessment for insulin resistance values than controls. For irisin results, idiopathic infertility patients had significantly decreased values than controls indicating the potential effect of irisin in development of insulin resistance in idiopathic infertility patients. 相似文献
102.
103.
Diaa-Eldin A. Mansour Nagat M. K. Abdel-Gawad Adel Z. El Dein Hanaa M. Ahmed Mohamed M. F. Darwish Matti Lehtonen 《Materials》2021,14(1)
Polymer nanocomposites used in underground cables have been of great interest to researchers over the past 10 years. Their preparation and the dispersion of the nanoparticles through the polymer host matrix are the key factors leading to their enhanced dielectric properties. Their important dielectric properties are breakdown strength, permittivity, conductivity, dielectric loss, space charge accumulation, tracking, and erosion, and partial discharge. An overview of recent advances in polymer nanocomposites based on LDPE, HDPE, XLPE, and PVC is presented, focusing on their preparation and electrical properties. 相似文献
104.
Karle CA Bauer A Weretka S Zitron E Abushi A Kreye VA Schoels W 《Basic research in cardiology》2002,97(1):17-25
Chromanol 293B and dofetilide are inhibitors of IKs and IKr, i.e., of the slow and the rapid component of the delayed rectifier potassium current. The specificity of these drugs was
tested by investigating their effects on the delayed rectifier potassium current in vascular smooth muscle, regulating the
tone of blood vessels. Using depolarizing step protocols with asymmetrical potassium concentrations (135/4.5 mM K+ in pipette/bath), voltage-dependent K+ currents (IKv) of enzymatically dispersed guinea pig portal vein cells were studied in the whole-cell patch-clamp technique. Peak currents
were obtained within 20 ms (at +50 mV) after activation. During a 10 s test pulse to +60 mV, these currents exhibited a relatively
fast inactivation with time constants of 384 ms (τfast) and 4505 ms (τslow). Dofetilide was totally ineffective in modulating currents; in contrast, after application of chromanol 293B, a steady-state
block of IKv developed within 135 s. The block was concentration-dependent with an IC50 of 7.4 μM. Chromanol did not produce any shift in the normalized steady-state activation and inactivation curves and the
recovery from inactivation was not significantly changed. Chromanol 293B similarly inhibited delayed rectifier K+ channels whether in their closed or open state, and produced an “apparent” acceleration of inactivation, i.e., the drug accelerated
the faster time constant of inactivation during a 10 s test pulse from 384 ms (control) to 149 ms (100 μM chromanol). In recent
studies, chromanol was described as a specific blocker of slowly activating delayed rectifier potassium channels (IKs) in cardiomyocytes. The results of this study, however, extend the inhibitory spectrum of the drug and demonstrate block
of closed and open state delayed rectifier K+ currents in portal vein vascular smooth muscle. Such a block could possibly contribute to the generation of portal hypertension.
Received: 2 March 2001, Returned for 1. revision: 22 March 2001, 1. Revision received: 9 May 2001, Returned for 2. revision:
16 May 2001, 2. Revision received: 3 August 2001, Accepted: 20 August 2001 相似文献
105.
Small-molecule XIAP inhibitors derepress downstream effector caspases and induce apoptosis of acute myeloid leukemia cells 总被引:16,自引:0,他引:16
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Carter BZ Gronda M Wang Z Welsh K Pinilla C Andreeff M Schober WD Nefzi A Pond GR Mawji IA Houghten RA Ostresh J Brandwein J Minden MD Schuh AC Wells RA Messner H Chun K Reed JC Schimmer AD 《Blood》2005,105(10):4043-4050
We tested the effects of small-molecule XIAP antagonists based on a polyphenylurea pharmacophore on cultured acute myelogenous leukemia (AML) cell lines and primary patient samples. X-linked inhibitor of apoptosis protein (XIAP) antagonist N-[(5R)-6-[(anilinocarbonyl)amino]-5-((anilinocarbonyl){[(2R)-1-(4-cyclohexylbutyl)pyrrolidin-2-yl]methyl}amino)hexyl]-N-methyl-N'-phenylurea (1396-12), but not a structurally related control compound, induced apoptosis of primary leukemia samples with a lethal dose (LD50) of less than 10 microM in 16 of 27 (60%) samples. In contrast, XIAP antagonist 1396-12 was not lethal to the normal hematopoietic cells in short-term cytotoxicity assays. Response of primary AML specimens to XIAP inhibitor correlated with XIAP protein levels, with higher levels of XIAP associated with sensitivity. The XIAP antagonist 1396-12 induced activation of downstream caspases 3 and 7 prior to the activation of upstream caspase 8 and caspase 9. Apoptosis induction was also independent of B-cell lymphoma protein-2 (Bcl-2) or caspase 8, indicative of a downstream effect on apoptotic pathways. Thus, polyphenylurea-based XIAP antagonsists directly induce apoptosis of leukemia cells and AML patient samples at low micromolar concentrations through a mechanism of action distinct from conventional chemotherapeutic agents. 相似文献
106.
Nasser Mohammad Taha Hany Taha Asklany Adel Hamdy Mahmoud Laila Hammoda Heba Rady Attallah Adel Mohammad Kamel Mohammad AbdelKader AbdelWahab 《The Egyptian Heart Journal》2018,70(3):167-171
Background
Obstructive coronary artery disease (OCAD) and coronary slow flow (CSF) are frequent angiographic findings for patients that have chest pain and require frequent hospital admission. The retina provides a window for detecting changes in microvasculature relating to the development of cardiovascular diseases such as arterial hypertension or coronary heart disease.Objectives
To assess the coronary and ocular circulations in patients with CSF and those with obstructive coronary artery disease.Methods
A prospective study was conducted over 3.5?years, included a total of 105 subjects classified to 4 groups: Group I (OCAD): Included 30 patients with obstructive coronary artery disease, group II (CSF): Included 30 patients with coronary slow-flow, group III (Control 1): Included 30 healthy control persons and group IV (Control 2): Included 15 patients indicated for coronary angiography that proved normal. All participants were subjected to coronary angiography (except control group 1), ophthalmic artery Doppler for measuring Pulsatility index (PI) and resistivity index (RI) and Fluorescence angiography of retinal vessels.Results
Patients with CSF showed slow flow retinal circulation (microcirculation) evidenced by prolonged fluorescein angiography (Arm-retina time [ART] & Arterio-venous Transit time [AVTT]). Ophthalmic artery Doppler measurements (RI & PI) were significantly delayed in OCAD and CSF patients. There was significant positive correlation between TIMI frame count in all subjects and ART, AVTT, PI, RI and Body Mass Index. Using ART cutoff value of >16?s predicted CSF with sensitivity and specificity of 100%, meanwhile AVTT of >2?s predicted CSF with a sensitivity 96.7% and specificity of 93.3.Conclusion
Both delayed arm-retina time and retinal arterio-venous transit times can accurately predict coronary slow-flow. 相似文献107.
Jamal Ahmadzadeh Behnam Mansorian Mohammad Mirza-Aghazadeh Attari Ira Mohebbi Raha Naz-Avar Karaim Moghadam Seyyed Adel Khoshbou Ghareh-bagh 《Diabetes & Metabolic Syndrome: Clinical Research & Reviews》2018,12(1):17-21
Aims
Some studies have demonstrated that metabolic syndrome is associated with hematological parameters. The present study explores the relationship between hematological parameters and numbers of metabolic syndrome conditions in Iranian men.Methods
This cross-sectional study included 11,114 participants who were professional drivers of commercial motor vehicles, and were enrolled in the Iranian Health Surveys between 2014 and 2016. Diagnosis of metabolic syndrome was made according to International Diabetes Federation criteria. Clinical data, including anthropometric measurements and serum parameters, were collected. Odds ratios for hematological parameters and metabolic syndrome were calculated using binary logistic regression models.Results
We found that hemoglobin; platelet, and white blood cell counts increased with increasing numbers of metabolic syndrome components (p < 0.05 for all). The odds ratio of metabolic syndrome significantly increased across successive quartiles of platelet (1.00, 1.25, 1.29, and 1.51) and white blood cell counts (1.00, 1.51, 1.79, and 2.11) with the lowest quartile as the referent group. Similar associations for hemoglobin and hematocrit in the top quartile were also observed. We did not observe any significant difference in the mean of neutrophil count, mean platelet volume (MPV), red cell distribution width, or platelet distribution width among participants with or without metabolic syndrome.Conclusions
Our findings indicate that high levels of major hematological parameters such as hemoglobin, hematocrit, as well as platelet and white blood cell counts could be novel indicators for the development of metabolic syndrome. 相似文献108.
109.
Mohamed Waheed Basyouni Adel Mohamed Shabana Wael Mahmoud El Kilani 《The Egyptian Heart Journal》2018,70(4):295-299
Background
Atherosclerosis is progressive and diffuse pathological disorders which can simultaneously affect multiple vascular beds. Diagnosing Lower extremities peripheral arterial disease (PAD) in patients with Coronary artery disease (CAD) admitted to cardiac rehabilitation program can help to tailor exercise regimen to fit these patients, in addition, early treatment and/or intervention may help to control progression of the disease.Aim
The study is to search for the prevalence of undiagnosed PAD using ankle brachial index (ABI) in Egyptian patients with documented CAD undergoing cardiac rehabilitation program.Patients and Methods
The study included 200 patients with documented CAD scheduled for cardiac rehabilitation in Cardiology department, Ain Shams University, with exclusion of patients with known (diagnosed) PAD. All patients underwent ABI using Doppler ultrasonography. The patients were divided into two groups; Study group with positive ABI (≤?0.9) and Control group with negative ABI (>?0.9).Results
We found that the prevalence of undiagnosed PAD in those patients was 14.5% (29 patients). The incidence of PAD is increased in patients above 60 years (p?=?0.001) and in presence of hypertension/uncontrolled systolic blood pressure (p?=?0.002), Dyslipidemia (p?=?0.005), or family history of ischemic heart disease (p?=?0.035). PAD is associated also with impaired left ventricular systolic function and presence of segmental wall motion abnormalities at rest. Impaired eGFR increased the risk of development of PAD (p?=?0.016). PAD was associated more with patients presented by multivessel lesions by coronary angiography and in presence of ischemic ECG changes.Conclusion
This study shows that significant PAD is present in almost 15% of ischemic Egyptian patients. We recommend ABI to be done routinely in patients with significant CAD for exclusion or diagnosis of PAD to help in treatment and improving quality of life in addition to modification of cardiac rehabilitation program in presence of PAD according to its severity. 相似文献110.
Adel A. Youssef Sathanur R. Srinivasan Abdalla Elkasabany Wei Chen Gerald S. Berenson 《Metabolism: clinical and experimental》2001,50(12):1441-1446
Although dyslipidemia among offspring of parents with coronary heart disease (CHD) has been known, the development of this adverse relationship with respect to specific lipoprotein variables from childhood to young adulthood has not been elucidated. This aspect was examined in a young adult cohort with (n = 271) and without (n = 805) a parental history of CHD followed longitudinally since childhood by repeated surveys from 1973 to 1991. Trends in fasting lipoprotein variables by parental CHD status were assessed by Lowess smoothing curve and Generalized Estimating Equations (GEE). In multivariate analyses adjusted for race and sex, parental CHD associated positively with low-density lipoprotein cholesterol (LDL-C, P <.01) and triglycerides (P <.05) mainly at the young adulthood age, whereas a positive association was noted with very-low-density lipoprotein cholesterol (VLDL-C) during both childhood and young adulthood (P <.05). The positive association between parental CHD and LDL-C in young adulthood persisted independently of body mass index (BMI) and fasting insulin, but disappeared when fasting glucose was added to the model. With respect to triglycerides and VLDL-C, inclusion of BMI, insulin, and/or glucose eliminated the adverse association with parental CHD. These observations suggest that parental CHD is just one more explanatory variable that loses its partial contribution to lipoprotein profiles in their offspring when other strongly interrelated contributory variables such as age, body fatness, and measures of glucose homeostasis are taken into account. Information on these risk variables in conjunction with parental or family history of CHD may enhance the potential of CHD risk assessment in youth. 相似文献