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41.
Methods:Data on 11 robot-assisted laparoscopic partial nephrectomies performed by using our technique from February 2015 through June 2015 were retrospectively analyzed. The robotic platform used was DaVinci Xi (Intuitive Surgical, Inc., Sunnyvale, California, USA) with a 3-arm setup. The AirSeal system (SurgiQuest, Milford, Connecticut, USA) was used as a port allowing simultaneous introduction of 2 instruments for the bedside surgeon, obviating the need for an additional (fourth) robotic arm. A long suction-and-irrigation device and atraumatic grasping forceps were used. Both instruments were introduced through the trocar of the AirSeal system, making simultaneous introduction and use possible. We preferred the long suction-and-irrigation device, because it minimizes collision of the instruments.Results:Mean age and BMI of the patients were 55 ±14.6 y and 29.18 ± 6.85, respectively. Seven tumors were on the right side and 4 were on the left. The mean size of the tumors was 32.45 mm (± 11.31). Surgical time was 132.2 minutes (±37.17), with an estimated blood loss and ischemia time of 103.63 mL (±65.92) and 16.72 minutes (±9.52), respectively. One patient had postoperative bleeding that was resolved without transfusion. The median hospitalization period was 3.9 d (±0.53). Loss of intra-abdominal pressure was not observed, and pressure was stable at 10 mm Hg.Conclusion:The AirSeal System and its valveless trocar eliminated the need for an additional port placement in our series. The technique is feasible, safe, and reproducible; therefore, it may be implemented in selected cases of robot-assisted partial nephrectomies.  相似文献   
42.
The aim of the study was to determine the effect of β-glucan on the cytotoxicity and genotoxicity of polypectomized patient's fecal water (FW). Polypectomized volunteers (n = 69) were randomly assigned to consume bread with or without β-glucan, for 3 months. FW was collected at the beginning (t = 0), the 30th and 90th day and 2 wk after the intervention. Cytotoxicity and genotoxicity were estimated on Caco-2 cells, using trypan blue exclusion test and comet assay, respectively. Gastrointestinal symptoms were recorded and subjects kept a 3-day food diary at baseline and after completion. Trypan blue exclusion test revealed cell survival of approximately 87% after incubation with FW. The FW samples showed 49% genotoxicity at the baseline. Genotoxicity in the intervention group decreased during the trial reaching statistical significance on the 90th day compared to control. An increase was noticed 2 wk after the trial, but it still remained significantly lower compared to control. Group-specific analysis for β-glucan also revealed significant decrease in the genotoxicity on the 90th day compared to baseline. β-glucan ingestion in polypectomized patients significantly decreased the genotoxicity of their FW. Our findings suggest that β-glucan consumption could possibly provide protection against colon cancer development.  相似文献   
43.
Several tools to facilitate the risk assessment and management of manufactured nanomaterials (MN) have been developed. Most of them require input data on physicochemical properties, toxicity and scenario-specific exposure information. However, such data are yet not readily available, and tools that can handle data gaps in a structured way to ensure transparent risk analysis for industrial and regulatory decision making are needed. This paper proposes such a quantitative risk prioritisation tool, based on a multi-criteria decision analysis algorithm, which combines advanced exposure and dose-response modelling to calculate margins of exposure (MoE) for a number of MN in order to rank their occupational risks. We demonstrated the tool in a number of workplace exposure scenarios (ES) involving the production and handling of nanoscale titanium dioxide, zinc oxide (ZnO), silver and multi-walled carbon nanotubes. The results of this application demonstrated that bag/bin filling, manual un/loading and dumping of large amounts of dry powders led to high emissions, which resulted in high risk associated with these ES. The ZnO MN revealed considerable hazard potential in vivo, which significantly influenced the risk prioritisation results. In order to study how variations in the input data affect our results, we performed probabilistic Monte Carlo sensitivity/uncertainty analysis, which demonstrated that the performance of the proposed model is stable against changes in the exposure and hazard input variables.  相似文献   
44.
We describe the case of a 31-year-old man who experienced an acute myocardial infarction 16 years after undergoing radiation and vinca alkaloid therapy for Hodgkin's disease. Even though coronary artery disease is a well-established complication after mediastinal radiation therapy, this adult patient had normal coronary angiographic results, with no traditional risk factors for coronary artery disease, and no hematologic or other abnormality associated with hypercoagulability.  相似文献   
45.
Objective Mechanically ventilated patients in the intensive care unit cannot cooperate to perform the Valsalva maneuver during echocardiography for detection of patent foramen ovale. We evaluated the effectiveness of the end-inspiratory occlusion maneuver to enhance detection of patent foramen ovale in this patient population. Design Prospective interventional study. Setting The 40-bed intensive care unit of a university hospital. Patients and participants Twenty five sedated and mechanically ventilated intensive care unit patients referred by their attending physician for bedside transesophageal echocardiography and agitated saline contrast study for detection of patent foramen ovale. Intervention Agitated saline contrast study with end-inspiratory occlusion maneuver. Measurements and results All patients underwent a complete transesophageal echocardiographic study without any complications. Reduction in right atrial cross-sectional area (from 15.80 ± 6.08 cm2 to 12.40 ± 4.63 cm2; p < 0.001) and interatrial septum deviation during the maneuver were recorded in all patients. Microbubbles imaged in the left atrium within three cardiac cycles after injection of agitated saline diagnosed patent foramen ovale in three patients. When end-inspiratory occlusion maneuver was added, patent foramen ovale was diagnosed in seven patients (McNemar χ2 = 9.33, p = 0.0023). Conclusions The end-inspiratory occlusion maneuver enhances the sensitivity of transesophageal echocardiography with agitated saline contrast study for diagnosing intermittent patent foramen ovale in critically ill mechanically ventilated patients. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
46.

Background

Lipid core expansion is partly responsible for the conversion of a stable atherosclerotic lesion to a rupture-prone plaque. Intraplaque hemorrhage contributes to the accumulation of cholesterol within unstable plaques. In the present study, we investigated, using a rabbit model of atherosclerosis, the extent to which diet-induced increases in cholesterol content of erythrocyte membranes (CEM) contribute to lipid core expansion and the modulatory effect of rosuvastatin use.

Methods and results

Rabbits fed with atherogenic diet (0.75% cholesterol) for 5 months exhibited advanced atherosclerotic lesions (mean plaque area, 0.39 ± 0.03 mm2), and lipid core size was associated with the concentration–time integral (CTI) of CEM levels (r = 0.567, P = 0.004) independent of other established predictors of lipid core size. Further experiments were performed by feeding rabbits atherogenic diet (1% cholesterol) for 3 months, followed by either normal diet or normal diet plus rosuvastatin for the next 3 months. Although no differences were observed in total plaque area between both groups, administration of rosuvastatin was associated with significantly smaller lipid cores, fewer macrophages within the lipid core, less microvessels as well as with lower CTI of CEM levels compared to normal diet alone. Moreover, intraplaque erythrocyte membranes covered a smaller lipid core area in rabbits under rosuvastatin plus normal diet as opposed to rabbits under diet alone.

Conclusions

Increased CEM levels, induced by high-cholesterol diet, are associated with lipid core growth. Ingestion of a potent HMG-CoA reductase inhibitor (rosuvastatin) may decrease CEM levels, and this effect may contribute to regression of the lipid core.  相似文献   
47.
Background/aims: Antimitochondrial antibodies (AMAs) are the serological hallmark of primary biliary cirrhosis (PBC). We evaluated the sensitivity and specificity of a new M2 enhanced performance enzyme-linked immunosorbent assay (ELISA) (MIT3) for the detection of IgG- and IgA-specific isotypes of AMA in PBC patients including a number of PBC patients negative for AMA by indirect immunofluorescence (IIF) as well as in patients with diverse, non-PBC disorders. We also investigated the clinical significance of IgG and IgA AMA in PBC. Methods: One hundred and three Greek PBC patients including 27 with AMA IIF-negative at the time of the investigation, 29 with autoimmune hepatitis-1 (AIH-1), 12 with primary sclerosing cholangitis (PSC), 26 with hepatitis C virus (HCV), 15 with hepatitis B virus (HBV), and 29 healthy were investigated for AMA (IgG and IgA) using the MIT3-based ELISAs (INOVA Diagnostics, San Diego, CA). The samples were also tested by conventional anti-M2 ELISA (INOVA Diagnostics, Inc.). Results: The IgG MIT3-based ELISA significantly increased AMA detection in the cohort of PBC patients, over 26% of whom were AMA IIF-negative, from 63.1% by the conventional anti-M2, and 73.7% by IIF to 79.6% by MIT3-based ELISA (p<0.001). IgA AMAs were detected in 47.6% patients. Overall, IgG/IgA AMAs were detected in 84/103 (81.6%). IgG MIT3-based ELISA detected 12/27 IIF AMA-negative samples (44.4%), while IgG/IgA MIT3-based ELISAs detected 13/27 IIF AMA-negative patients (48.1%). The specificities of MIT3-based ELISAs (IgG and IgA) were 82.8% and 89.7%, respectively, in AIH-1, 100% and 93.3%, respectively, in HBV, 100% in PSC, and 96% and 93.3%, respectively, in HCV. Patients positive for IgG AMA had significantly more severe disease as shown by worse histology and elevated biochemical markers; IgG and IgA AMA titers were associated positively with the Mayo risk score but none of the isotypes were able to predict disease outcome. Conclusions: The new IgG and IgA MIT3-based ELISAs seem to have higher specificity and sensitivity for AMA detection than IIF and the conventional anti-M2. Interestingly, these assays were able to unmask AMA presence in almost half of the AMA-negative samples by IIF. These findings may suggest the use of MIT3-based ELISAs as first-line investigation for AMA detection, particularly, when the laboratories are unfamiliar with the use and interpretation of the IIF patterns of AMA. The presence of IgG AMA seems to characterize PBC patients with more severe disease, but both IgG and IgA isotypes of AMAs were not predictive markers of disease outcome.  相似文献   
48.
Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2, broke out in December 2019 in Wuhan city of China and spread rapidly worldwide. Therefore, by March 2020, the World Health Organization declared the disease a global pandemic. Apart from the respiratory system, various other organs of the human body are also seriously affected by the virus. Liver injury in patients with a severe form of COVID-19 is estimated to be 14.8%-53.0%. Elevated levels of total bilirubin, aspartate aminotransferase and alanine aminotransferase and low levels of serum albumin and prealbumin are the main laboratory findings. Patients with pre-existing chronic liver disease and cirrhosis are much more prone to develop severe liver injury. This literature review presented the recent scientific findings regarding the pathophysiological mechanisms responsible for liver injury in critically ill patients with COVID-19, the various interactions between drugs used to treat the disease and the function of the liver and the specific tests providing the possibility of early diagnosis of severe liver injury in these patients. Moreover, it highlighted the burden that COVID-19 put on health systems worldwide and its effect on transplant programs and the care provided to critically ill patients in general and particularly to those with chronic liver disease.  相似文献   
49.
Although nonmyeloablative conditioning regimen transplantations (NMTs) induce engraftment of allogeneic stem cells with a low spectrum of toxicity, graft-versus-host disease (GVHD) remains a significant cause of morbidity and mortality. In vivo T-cell depletion, using alemtuzumab, has been shown to reduce the incidence of GVHD. However, this type of maneuver, although reducing GVHD, may have an adverse impact on disease response, because NMTs exhibit their antitumor activity by relying on a graft-versus-malignancy effect. To explore the efficacy of alemtuzumab compared with methotrexate (MTX) for GVHD prophylaxis, we have compared the results in 129 recipients of a sibling NMT enrolled in 2 prospective studies for chronic lymphoproliferative disorders. Both NMTs were based on the same combination of fludarabine and melphalan, but the United Kingdom regimen (group A) used cyclosporin A plus alemtuzumab, whereas the Spanish regimen (group B) used cyclosporin A plus MTX for GVHD prophylaxis. Patients receiving alemtuzumab had a higher incidence of cytomegalovirus (CMV) reactivation (85% versus 24%, P <.001) and a significantly lower incidence of acute GVHD (21.7% versus 45.1%, P =.006) and chronic GVHD (5% versus 66.7%, P <.001). Twenty-one percent of patients in group A and 67.5% in group B had complete or partial responses 3 months after transplantation (P <.001). Eighteen patients in group A received donor lymphocyte infusions (DLIs) to achieve disease control. At last follow-up there was no difference in disease status between the groups with 71% versus 67.5% (P =.43) of patients showing complete or partial responses in groups A and B, respectively. No significant differences were observed in event-free or overall survival between the 2 groups. In conclusion, alemtuzumab significantly reduced GVHD but its use was associated with a higher incidence of CMV reactivation. Patients receiving alemtuzumab often required DLIs to achieve similar tumor control but the incidence of GVHD was not significantly increased after DLI.  相似文献   
50.

1 Background

Radiofrequency (RF) ablation of the slow pathway (SP) in atrioventricular nodal reentry tachycardia (AVNRT) is occasionally complicated with atrioventricular block (AVB) often predicted by junctional beats (JB) with loss of ventriculo‐atrial (VA) conduction.

2 Methods

We analyzed retrospectively 153 patients undergoing ablation of SP for typical AVNRT. Patients were divided into two age groups: 127 ≤ 70 years and 26 > 70 years. We analyzed the interval between the atrial electrogram in the His‐bundle position and the distal ablation catheter [A(H)‐A(RFd)] and between the distal ablation catheter and the proximal coronary sinus catheter [A(RFd)‐A(CS)] before RF applications with and without JB. We evaluated if these intervals can be used as predictors of JB incidence and also of JB with loss of VA conduction. We also assessed if age influences the risk of loss of VA conduction.

3 Results

The A(H)‐A(RFd) and A(RFd)‐A(CS) intervals were significantly shorter in RF applications causing JB than those without JB (33 ± 11 ms vs 39 ± 9 ms, P < 0.001, 14 ± 9 ms vs 20 ± 7 ms, P < 0.001, respectively). The A(H)‐A(RFd) and A(RFd)‐A(CS) intervals were also significantly shorter in RFs causing JB with VA block than those with VA conduction (29 ± 11 ms vs 35 ± 11 ms, P < 0.001, 8 ± 8 ms vs 17 ± 8 ms, P < 0.001, respectively). Patients > 70 years had shorter intervals (36 ± 11 ms vs 29 ± 8 ms, P  =  0.012, 17 ± 8 ms vs 13 ± 7 ms, P  =  0.027, respectively), while VA block was more common in this age group.

4 Conclusions

The A(H)‐A(RFd) and A(RFd)‐A(CS) intervals can be used as markers for predicting JB occurrence as well as impending AVB. JB with loss of VA conduction occur more often in older patients possibly due to a higher position of SP.  相似文献   
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