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1.
Krishna S. Iyer 《Platelets》2020,31(4):474-482
Abstract

Platelets are small, anucleated effector cells that play an important role in linking the hemostatic and inflammatory processes in the body. Platelet function is known to be altered under various inflammatory conditions including aging. A gain in platelet function during aging can increase the risk of thrombotic events, such as stroke and acute myocardial infarction. Anti-platelet therapy is designed to reduce risk of serious cerebrovascular and cardiovascular events, but the adverse consequences of therapy, such as risk for bleeding increases with aging as well. Age-associated comorbidities such as obesity, diabetes, and hyperlipidemia also contribute to increased platelet activity and thus can enhance the risk of thrombosis. Therefore, identification of unique mechanisms of platelet dysfunction in aging and in age-associated comorbidities is warranted to design novel antiplatelet drugs. This review outlines some of the current areas of research on aging-related mechanisms of platelet hyperactivity and addresses the clinical urgency for designing anti-platelet therapies toward novel molecular targets in the aging population.  相似文献   
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Thermal ablation of liver tumors near large blood vessels is affected by the cooling effect of blood flow, leading to incomplete ablation. Hence, we conducted a comparative investigation of heat sink effect in monopolar (MP) and bipolar (BP) radiofrequency ablation (RFA), and microwave (MW) ablation devices.With a perfused calf liver, the ablative performances (volume, mass, density, dimensions), with and without heat sink, were measured. Heat sink was present when the ablative tip of the probes were 8.0 mm close to a major hepatic vein and absent when >30 mm away. Temperatures (T1 and T2) on either side of the hepatic vein near the tip of the probes, heating probe temperature (T3), outlet perfusate temperature (T4), and ablation time were monitored.With or without heat sink, BP radiofrequency ablated a larger volume and mass, compared with MP RFA or MW ablation, with latter device producing the highest density of tissue ablated. MW ablation produced an ellipsoidal shape while radiofrequency devices produced spheres.Percentage heat sink effect in Bipolar radiofrequency : Mono-polar radiofrequency : Microwave was (Volume) 33:41:22; (mass) 23:56:34; (density) 9.0:26:18; and (relative elipscity) 5.8:12.9:1.3, indicating that BP and MW devices were less affected.Percentage heat sink effect on time (minutes) to reach maximum temperature (W) = 13.28:9.2:29.8; time at maximum temperature (X) is 87:66:16.66; temperature difference (Y) between the thermal probes (T3) and the temperature (T1 + T2)/2 on either side of the hepatic vessel was 100:87:20; and temperature difference between the (T1 + T2)/2 and temperature of outlet circulating solution (T4), Z was 20.33:30.23:37.5.MW and BP radiofrequencies were less affected by heat sink while MP RFA was the most affected. With a single ablation, BP radiofrequency ablated a larger volume and mass regardless of heat sink.  相似文献   
3.
A local pedicled vascularized bone flap can prevent the morbidity and cost of free bone flap surgery in small segmental bone defects or long cartilaginous defects of the head and neck. Such flaps can also be useful in patients who are high risk for surgery. The periosteal vascularity of the mandible can be used to design islanded facial artery-based bone flaps, which can be utilized to that extent. Two patients with a small segmental mandibulectomy defect and one patient with a long cricotracheal resection defect underwent reconstruction using three different designs of islanded facial artery osteomyomucosal/osseous flap (iFOMM). The patients had a minimum follow-up period of 18 months. All flaps were successful, with satisfactory healing and without any functional deficit or disease at last follow-up.  相似文献   
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Objective

Hypertonic saline (HTS) has potent immune and vascular effects. We assessed recipient pretreatment with HTS on allograft function in a porcine model of heart transplantation and hypothesized that HTS infusion would limit endothelial and left ventricular (LV) dysfunction following transplantation.

Methods

Heart transplants were performed after 6 hours of cold ischemic storage. Recipient pigs were randomized to treatment with or without HTS (7.5% NaCl) before cardiopulmonary bypass (CPB). Using a myograft apparatus, coronary artery endothelial-dependent (Edep) and -independent (Eind) relaxation was assessed. LV performance was determined using pressure-volume loop analysis. Pulmonary interleukin (IL)-2, IL-6, and tumor necrosis factor (TNF)-α expression was measured.

Results

Weaning from CPB and LV performance after transplantation were improved in HTS-treated animals. Successful weaning from CPB was greater in the HTS-treated hearts (8 of 8 vs 2 of 8; P < .05). Mean LV functional recovery was improved in the HTS-treated animals, as assessed by preload recruitable stroke work (65 ± 10% vs 27 ± 10%; P < .001) and end-systolic elastance (55 ± 7% vs 37 ± 4%; P < .001). Treatment with HTS resulted in improved Edep (mean maximum elastance [Emax], 56 ± 5% vs 37 ± 7%; P < .001) and Eind (mean Emax%, 77 ± 6% vs 52 ± 4%; P < .001) vasorelaxation compared with control. Pulmonary expression of IL-2, IL-6, and TNF-α increased following transplantation, whereas HTS therapy attenuated IL production (P < .001). Transplantation increased plasma TNF-α levels and LV TNF-α expression, whereas HTS prevented this up-regulation (P < .001).

Conclusions

Recipient HTS pretreatment preserves allograft vasomotor and LV function, and HTS therapy limits CPB-induced injury. HTS may be a novel recipient intervention to prevent graft dysfunction.  相似文献   
7.
目的:观察中西医结合治疗排卵障碍性不孕症的疗效。方法:82例按随机数字表法分为对照组和观察组各41例。两组均给予常规西药治疗,观察组加用腹针温阳法治疗。结果:受孕成功率观察组84.44%,对照组71.11%,两组比较差异有统计学意义(P<0.05)。观察组优质卵泡直径小于对照组(P<0.05),优质卵泡数量以及子宫内膜厚度均高于对照组(P<0.05)。两组卵巢动脉血流PI、RI、PSV与EDV指标均优于治疗前(P<0.05),且观察组各项指标均优于对照组(P<0.05)。结论:中西医结合治疗排卵障碍性不孕症可改善卵泡发育以及卵巢动脉血流指标,提高受孕率。  相似文献   
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Endoscopic clips have been used mainly for control of gastrointestinal (GI) bleeding and occasionally for closure of GI perforations. However, closure of spontaneous esophageal perforation (Boerhaave's syndrome) by clipping has not been reported. We described successful non-surgical closure of spontaneous esophageal perforation by endoscopic clipping in a patient with bilateral pyopneumothorax and septicemia.  相似文献   
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