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OBJECTIVE: One of the complications of CPB is the systemic inflammatory response syndrome (SIRS). Recent developments tend to minimize the biological impact of CPB in using miniaturized closed circuit with reduced priming volume and less blood-air interface. The benefit of these miniaturized closed circuits in terms of inflammatory response has been proved in coronary surgery. However, in open heart surgery, the CPB circuit is no more closed and the benefit of the miniaturized set-up could disappear. The aim of the study is to compare the SIRS between standard and miniaturized circuits in aortic surgery. METHODS: Forty patients who underwent singular aortic valve replacement were randomly assigned either to a standard CPB (group A, n=20) or to a miniaturized CPB (group B, n=20). Pertinent clinical and surgical data were collected. Hematological parameters (leukocyte and neutrophil counts) and biochemical parameters (C-reactive protein, cytokine tests) were determined pre-, on and post-CPB. RESULTS: There were an increase in leukocyte and neutrophil counts and a decline in hematocrit in both groups. In both groups, there was a raise after CPB, in C-reactive protein, IL-6, TNF-alpha, neutrophil elastase, and IL-10. However, the raises of elastase and TNF-alpha were significantly lower after the weaning of miniaturized CPB (116+/-46 ng/ml and 10+/-4 pg/ml, respectively) compared to standard CPB (265+/-120 ng/ml, P=0.01 and 18+/-7 pg/ml, P=0.03). The raise of IL-10 is also lower with miniaturized circuit (15+/-6 pg/ml) compared to standard circuit (51+/-26, P=0.004). CONCLUSIONS: This study demonstrates in aortic surgery, the lesser inflammatory response of a miniaturized CPB compared to a standard CPB. However, there is always some inflammation after CPB and a small bio-reactive free perfusion circuit is still to be found in open heart surgery.  相似文献   
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BACKGROUND: The assembly of nuclear pore complexes (NPC) and their cytoplasmic stacks, annulate lamellae (AL), promote normal nucleocytoplasmic trafficking and accompany pronuclear development within the mammalian zygote. Previous studies showed that a percentage of human oocytes fertilized in vitro failed to develop normal pronuclei and cleave within 40-48 h post insemination. We hypothesized that an aberrant recruitment of NPC proteins, nucleoporins and/or NPC preassembled into AL, might accompany human fertilization arrest. METHODS AND RESULTS: We explored NPC and AL assembly in unfertilized human oocytes, and fertilized and arrested zygotes by immunofluorescence with an NPC- and AL-specific antibody, mAb 414, and by transmission electron microscopy. Major NPC or AL assembly was not observed in the unfertilized human oocytes. Once fertilization took place, the formation of AL was observed throughout the cytoplasm and near the developing pronuclei with NPC. On the contrary, NPC assembly was disrupted in the arrested zygotes, whereas AL were clustered into large sheaths. This was accompanied by the lack of NPC incorporation into the nuclear envelopes. CONCLUSIONS: We conclude that the aberrant assembly of NPC and AL coincides with early developmental failure in humans.  相似文献   
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Superantigens related to B cell hyperplasia   总被引:1,自引:0,他引:1  
Conclusions In both mouse and humans, B cell hyperplasia is seen in many situations that involve T cell stimulation. In the mouse, some of these conditions appear to involve a SAg-induced T cell response, which can result in chronic B cell hyperplasia and development of B cell lymphomas. From our investigation of the B cell lymphomas that characteristically arise in a majority (90%) of SJL/J mice, it is clear that a vSAg which is encoded by a unique endogenous mammary tumor provirus is involved in the neoplastic process. The tumor-associated vSAg (mtv-29-LTR) stimulates a TCR V-restricted subset of T cells (V16+) to produce cytokines which the lymphoma cells use as paracrine growth factors for progressive growth. We speculate that themtv-29-encoded vSAg may be expressed on germinal center B cells, even in young SJL mice, and that the characteristic chronic B cell hyperplasia seen in this strain is driven by the cytokines produced by responding V16+ T cells. Moreover, the cytokine dependence of the SJL B cell lymphomas on IL-5 and IL-4 suggests that preferential stimulation of Th2 cells is involved. This scenario of B cell hyperplasia associated with SAg-induced Th2 cell stimulation may also be a major element in other murine models, such as chronic parent F1 GvHD and MAIDS.Mechanisms similar to those described in these mouse models may also be operative in human diseases caused by infectious microorganisms, such asH. pylori, EBV, HIV,M. arthritidis, mycobacteria, malarial parasites, and others. However, the involvement of SAgs in these conditions, and their precise role in eliciting from T cells those eytokines which promote chronic B cell hyperplasia and lymphoma development remain to be clearly defined. The possible role of T cells in similar disease mechanisms will need to be explored in the light of overwhelming evidence that certain unconventional antigens such as HSP stimulate subpopulations of these T cells. In our discussion of these diseases we have, therefore, given consideration to the possibility that the definition of SAg may have to be expanded to include such antigens.  相似文献   
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Twelve cerebral lesions were operated upon with various laser sources (carbon dioxide, neodymium-yttrium-argon-garnet, and argon) and with an ultrasonic aspirator utilizing the intraoperative "real-time" ultrasonography. With the last method, the tumor was imaged just as well through the intact dura mater as on the brain surface itself, allowing a precise localization of deep intracranial lesions. A sharp selectivity on the healthy tissues is, in this way, achievable to reach the tumor, which is successively removed with the laser and ultrasonic aspirator checking the surgical maneuvers on the visual control of the ultrasonograph.  相似文献   
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BackgroundThe clinical course of COVID-19 includes multiple disease phases. Data describing post-hospital discharge outcomes may provide insight into disease course. Studies describing post-hospitalization outcomes of adults following COVID-19 infection are limited to electronic medical record review, which may underestimate the incidence of outcomes.ObjectiveTo determine 30-day post-hospitalization outcomes following COVID-19 infection.DesignRetrospective cohort studySettingQuaternary referral hospital and community hospital in New York City.ParticipantsCOVID-19 infected patients discharged alive from the emergency department (ED) or hospital between March 3 and May 15, 2020.MeasurementOutcomes included return to an ED, re-hospitalization, and mortality within 30 days of hospital discharge.ResultsThirty-day follow-up data were successfully collected on 94.6% of eligible patients. Among 1344 patients, 16.5% returned to an ED, 9.8% were re-hospitalized, and 2.4% died. Among patients who returned to the ED, 50.0% (108/216) went to a different hospital from the hospital of the index presentation, and 61.1% (132/216) of those who returned were re-hospitalized. In Cox models adjusted for variables selected using the lasso method, age (HR 1.01 per year [95% CI 1.00–1.02]), diabetes (1.54 [1.06–2.23]), and the need for inpatient dialysis (3.78 [2.23–6.43]) during the index presentation were independently associated with a higher re-hospitalization rate. Older age (HR 1.08 [1.05–1.11]) and Asian race (2.89 [1.27–6.61]) were significantly associated with mortality.ConclusionsAmong patients discharged alive following their index presentation for COVID-19, risk for returning to a hospital within 30 days of discharge was substantial. These patients merit close post-discharge follow-up to optimize outcomes.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11606-021-06924-0.KEY WORDS: COVID-19, mortality, re-admission, discharge  相似文献   
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Background  

Fractures of the intertrochanteric hip are common and the treatment of unstable fractures generally requires an operative approach. In elderly patients, osteoporosis makes internal fixation problematic and frequently contributes to failed fixation and poor clinical results. We have attempted to apply the Less Invasive Stabilization System (LISS) in reverse position for the repair of intertrochanteric hip fractures in elderly patients with osteoporotic bones. A retrospective review is presented of the cases of 28 elderly patients with stable and unstable fractures of the intertrochanteric hip treated using the reverse LISS.  相似文献   
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BACKGROUND: Aim of this study was to evaluate the results of endovascular repair of abdominal aortic aneurysm (AAA) in patients considered not suitable for traditional open surgical repair because of the high anesthesiological risk. METHODS: We have retrospectively evaluated the result of the endovascular treatment of 11 patients with AAA of more than 6 cm diameter and high surgical risk due to cardiac hypokinesia and/or respiratory insufficiency. Patients were selected by a team composed of vascular surgeons and vascular radiologists who decided to implant the graft according to anatomical features of the AAA and of the iliac arteries. The treatment was performed in loco-regional anesthesia. The main end-points were: implantation success, mortality, morbidity, the absence of endoleak during the follow up that lasted two years. RESULTS: All the grafts were successfully implanted. There were no complications caused by anesthesiological manouvres. We had a minor intra-operative vascular complication and we performed three adjunctive endovascular procedures. A patient died of acute myocardial infarction, in the post operative period. Mean stay was six days. Pre-discharge scan showed 3 endoleaks (type I), two of these healed spontaneously and one sealed by percutaneous endovascular treatment. During follow-up (3-24 months) no patient died. One endoleak (type II) still persists. CONCLUSIONS The use of loco-regional anaesthesia allows us to treat high risk patients. Following strictly the criteria of patient selection, the surgical high risk seems not to influence significantly the mid term results that are almost equal to the ones obtained in low-risk patients.  相似文献   
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