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71.
Die Anaesthesiologie - Die Anlage einer Magensonde im OP oder auf einer Intensivstation (ITS) stellt eine alltäglich durchgeführte Prozedur dar. Obwohl die Sonde häufig durch...  相似文献   
72.

Purpose

Modulation of the immune system by the CNS may involve serotonergic regulation via the brain serotonin transporters (SERT). This regulation may be disturbed in patients with CNS disorders including multiple sclerosis (MS). Central serotonergic mechanisms have not been investigated in MS by in vivo imaging. The objective of the study was to assess the availability of SERT in antidepressant-naive patients with MS by means of PET.

Methods

Included in this study were 23 patients with MS and 22 matched healthy volunteers who were investigated with PET and the SERT-selective marker [11C]DASB, and distribution volume ratios were determined. Clinical assessment of the patients included the expanded disability status scale, the MS fatigue scale Würzburger Erschöpfungsinventar bei MS (WEIMuS) and the Beck Depression Inventory (BDI). The PET data were analysed with both volume-of-interest and voxel-based analyses to determine regional SERT availability.

Results

Patients had lower SERT availability in the cingulate cortex, the thalamus and the insula, and increased availability in the orbitofrontal cortex. Patients with relapsing/remitting MS tended to have lower SERT in the hippocampus, whereas patients with primary progressive disease showed increased SERT availability in prefrontal regions. There was a positive correlation between SERT availability in the insula and both depression and fatigue scores (r?=?0.56 vs. BDI, p?=?0.02; r?=?0.49 vs. WEIMuS, p?=?0.05).

Conclusion

Serotonergic neurotransmission in MS patients is altered in limbic and paralimbic regions as well as in the frontal cortex that this appears to contribute to psychiatric symptoms of MS.  相似文献   
73.
BACKGROUND: Cytolytic induction therapy with anti-thymocyte globulin (ATG) should induce effective immunosuppression, with a low rate of rejection in the initial phase after heart transplantation. Induction therapy with ATG allows post-operative renal recovery without the negative effects of highly nephrotoxic cyclosporine levels. An increased rate of infection is a common problem, however, and has been associated with "over-immunosuppression" early after transplantation. Therefore, we investigated whether reduced T-cell-adapted ATG induction therapy could be performed without increasing the risk of graft loss by rejection and whether reductions in infection rates and costs are possible. METHODS: Between March 1999 and December 2002, T-cell-adapted ATG induction therapy with ATG (Sangstat) (1.5 mg/kg) was given to 62 heart transplant recipients (study group) starting on post-operative Days 1 to 6. T-lymphocyte sub-populations were screened daily using flow cytometry. If total lymphocytes were <100/microl (reference 1,300 to 2,300/microl), T-helper lymphocytes (CD4+) <50/microl (reference >500/microl) and T-suppressor cells (CD8+) <50/microl (reference >300/microl), then no ATG was given. Further immunosuppression was continued with triple therapy consisting of methylprednisolone, azathioprine and cyclosporine. An historic group of heart transplant recipients given a full-dose ATG regimen for 8 days served as controls. These recipients were treated with ATG (Merieux 1.5 mg/kg) until reaching monoclonal cyclosporine levels of >300 mg/dl. Additional immunosuppressive treatment did not differ. Patients in both groups received systemic antibiotics (Imipenem) peri-operatively. Results of routine endomyocardial biopsies and rates of infections were examined. RESULTS: Study group patients were older (52 +/- 10 vs 49 +/- 14 years). In the study group, mean cumulative ATG dose was reduced significantly to 596 +/- 220 mg (p < 0.05) for 3.9 +/- 1.6 days compared with 1,159 +/- 376 mg for 6.9 +/- 1.1 days in the control group. The rate of cytomegalovirus (CMV) seroconversion was 23% in the study group compared with 13% in the control group. Rate of deep sternal infections was lower in the study group (1.6% vs 3.2%). The mean rejection rate in the first 3 months was 0.4 +/- 0.7 for the study patients (185 biopsies) vs 1.1 +/- 1.7 for controls (237 biopsies). All biopsies with ISHLT Grade >2 were treated successfully with 1,000 mg of methylprednisolone intravenously for 3 days. Both groups showed a similar 1-year survival rate (study 88%, control 89%). CONCLUSIONS: T-cell-adapted ATG induction therapy can be a helpful tool for individualized immunosuppression. It is not associated with an increased rate of rejection. Lower doses of immunosuppression help to minimize the rates of infection. In addition, cytolytic induction therapy combined with reduced ATG results in significant cost reduction.  相似文献   
74.
75.

PURPOSE

We aimed to describe the frequency of adverse events after computed tomography (CT) fluoroscopy-guided irreversible electroporation (IRE) of malignant hepatic tumors and their risk factors.

METHODS

We retrospectively analyzed 85 IRE ablation procedures of 114 malignant liver tumors (52 primary and 62 secondary) not suitable for resection or thermal ablation in 56 patients (42 men and 14 women; median age, 61 years) with regard to mortality and treatment-related complications. Complications were evaluated according to the standardized grading system of the Society of Interventional Radiology. Factors influencing the occurrence of major and minor complications were investigated.

RESULTS

No IRE-related death occurred. Major complications occurred in 7.1% of IRE procedures (6/85), while minor complications occurred in 18.8% (16/85). The most frequent major complication was postablative abscess (4.7%, 4/85) which affected patients with bilioenteric anastomosis significantly more often than patients without this condition (43% vs. 1.3%, P = 0.010). Bilioenteric anastomosis was additionally identified as a risk factor for major complications in general (P = 0.002). Minor complications mainly consisted of hemorrhage and portal vein branch thrombosis.

CONCLUSION

The current study suggests that CT fluoroscopy-guided IRE ablation of malignant liver tumors may be a relatively low-risk procedure. However, patients with bilioenteric anastomosis seem to have an increased risk of postablative abscess formation.About 70% of hepatic metastases are nonresectable because of their anatomic location, the presence of comorbidities, or limited hepatic functional reserve (1). In these patients and in case of nonresectable primary liver tumors, percutaneous thermal ablation procedures, such as radiofrequency (RF) and microwave ablation, have become effective tools for treating hepatic malignancies (24). However, the effectiveness of RF and microwave treatment may be limited, either because of thermal damage to temperature-sensitive structures located in close proximity to the target tissue (5) or because of incomplete ablation of tumors adjacent to major hepatic vessels due to a phenomenon commonly termed “heat-sink effect” (610) which describes the loss of the applied thermal energy through the blood flow in those major vessels, whereby the effective energy application remains inadequate to ablate the target lesion.Irreversible electroporation (IRE) is a theoretically nonthermal ablation technique that delivers a series of high-voltage millisecond electrical pulses to the surrounding tissue, thus leading to irreversible disruption of the integrity of cell membranes and subsequent cell death by apoptosis (1114). IRE may overcome the problems raised with thermal ablation: previous animal studies reported that bile ducts, blood vessels, nerves, and connective tissues are affected by IRE; however, regeneration is possible to some extent due to preservation of the tissue architecture (12, 13, 1519). Moreover the feasibility of inducing cell death up to a vessel wall without any perivascular sparing was shown with IRE (12, 13, 18). The safety of IRE in the treatment of humans has been described (20). First reports have described potential complications after IRE, such as hemorrhage requiring blood transfusion (1.2%, two of 167 ablation procedures), portal vein thrombosis (3.2%, one of 31 ablation procedures), injury to bile ducts (1.8%, three of 167 ablation procedures), and infection (3.6%, six of 167 ablation procedures) (21, 22). However, few data are available for evaluating the potential risk factors associated with the occurrence of post-IRE complications.The purpose of this study was to review the frequency of mortality and morbidity after computed tomography (CT) fluoroscopy-guided liver IRE conducted at a single center and assess the factors influencing the occurrence of major complications.  相似文献   
76.
Alcoholic liver disease (ALD) is the second most common indication for liver transplantation (LT). The utility of fixed intervals of abstinence prior to listing is still a matter of discussion. Furthermore, post‐LT long‐term observation is challenging, and biomarkers as carbohydrate‐deficient transferrin (CDT) may help to identify alcohol relapse. We retrospectively analyzed data from patients receiving LT for ALD from 1996 to 2012. A defined period of alcohol abstinence prior to listing was not a precondition, and abstinence was evaluated using structured psychological interviews. A total of 382 patients received LT for ALD as main (n = 290) or secondary (n = 92) indication; median follow‐up was 73 months (0–213). One‐ and five‐year patient survival and graft survival rates were 82% and 69%, and 80% and 67%, respectively. A total of 62 patients (16%) experienced alcohol relapse. Alcohol relapse did not have a statistically significant effect on patient survival (P = 0.10). Post‐transplant CDT measurements showed a sensitivity and specificity of 84% and 85%, respectively. In conclusion, this large single‐center analysis showed good post‐transplant long‐term results in patients with ALD when applying structured psychological interviews before listing. Relapse rates were lower than those reported in the literature despite using a strict definition of alcohol relapse. Furthermore, post‐LT CDT measurement proved to be a useful supplementary tool for detecting alcohol relapse.  相似文献   
77.

Purpose

Novel tracers for the diagnosis of malignant disease with PET and PET/CT are being developed as the most commonly used 18F deoxyglucose (FDG) tracer shows certain limitations. Employing radioactively labelled glutamate derivatives for specific imaging of the truncated citrate cycle potentially allows more specific tumour imaging. Radiation dosimetry of the novel tracer BAY 85-8050, a glutamate derivative, was calculated and the effective dose (ED) was compared with that of FDG.

Methods

Five healthy volunteers were included in the study. Attenuation-corrected whole-body PET/CT scans were performed from 0 to 90 min, at 120 and at 240 min after injection of 305.0?±?17.6 MBq of BAY 85-8050. Organs with moderate to high uptake at any of the imaging time points were used as source organs. Total activity in each organ at each time point was measured. Time–activity curves (TAC) were determined for the whole body and all source organs. The resulting TACs were fitted to exponential equations and accumulated activities were determined. OLINDA/EXM software was used to calculate individual organ doses and the whole-body ED from the acquired data.

Results

Uptake of the tracer was highest in the kidneys due to renal excretion of the tracer, followed by the pancreas, heart wall and osteogenic cells. The mean organ doses were: kidneys 38.4?±?11.2 μSv/MBq, pancreas 23.2?±?3.8 μSv/MBq, heart wall 17.4?±?4.1 μSv/MBq, and osteogenic cells 13.6?±?3.5 μSv/MBq. The calculated ED was 8.9?±?1.5 μSv/MBq.

Conclusion

Based on the distribution and dose estimates, the calculated radiation dose of BAY 85-8050 is 2.67?±?0.45 mSv at a patient dose of 300 MBq, which compares favourably with the radiation dose of FDG (5.7 mSv).  相似文献   
78.
79.

OBJECTIVES

To determine the technical feasibility and reproducibility of pure natural orifice transluminal endoscopic surgery (NOTES) transvaginal nephrectomy using NOTES‐specific instrumentation, with no transabdominal assistance.

MATERIALS AND METHODS

Five female farm pigs (mean weight 45 kg) had a right NOTES nephrectomy, using a single‐channel gastroscope in the first three pigs and a dual‐channel gastroscope in the remaining two. The peritoneal cavity was accessed through the posterior fornix of the vagina. Dissection was started at the lower pole of the kidney, and the ureter was retracted laterally and followed towards the hilum. An XL articulated 60 cm endo‐GIA stapler (US Surgical, Norwalk, CO, USA), inserted transvaginally via a separate vaginal incision, was used for tissue retraction and renal hilar transection. The kidney was freed, entrapped in an impermeable sac, and extracted intact transvaginally.

RESULTS

All five procedures were successful with no addition of a transabdominal laparoscopic port or open conversion. The total operative duration decreased from 200 min in the first pig to 60 min in the last (mean 113 min); the mean blood loss was <50 mL, the mean kidney length was 13.9 cm and the weight was 142 g. There were no intraoperative complications; at autopsy, there was no pelvic or bowel injury.

CONCLUSIONS

Pure NOTES transvaginal nephrectomy is feasible in the porcine model. It has the potential of a less morbid approach, providing truly scar‐less surgery. Further development of instrumentation is necessary.  相似文献   
80.
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