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101.

Introduction

The aim of our study is to establish a reliable neonatal rat model by formula feeding only for evaluation of early surgical intervention on the course of experimental necrotizing enterocolitis (NEC).

Material and methods

Newborn Sprague–Dawley rats were divided into 50 breast-fed (group 1) and 38 formula fed (Similac/Esbilac, group 2) animals. The pups were sacrificed on the 4th, 5th, and 6th day of life and the terminal intestine examined for macroscopic and histologic changes as well as cytokine expression.

Results

The histological mucosal damage was significantly higher of group 2 compared to group 1. The area of the vital mucosa of group 2 was significantly (58.57%, p < 0.001) lower compared to group 1 (75.12%). The mRNA expression of the inflammatory cytokines IL-6, IL-8 and COX-2 was significantly 2-, 5- and 10-fold increased in group 2 compared to group 1.

Discussion

Formula fed newborn rats displayed an inflammatory enterocolitis similar to human NEC. Our study demonstrates a significant loss of mucosa in animals with NEC having increased expression levels of IL-6, IL-8 and COX-2. Mucosal loss appears to be a distinct feature of experimental NEC and has to be correlated with the human disease.  相似文献   
102.
BACKGROUND: Interstitial brachytherapy with I-125 seeds can be used for successful treatment of early stage prostate cancer. There is presented the technique of permanent transperineal implantation of I-125 seeds with intraoperative treatment planning which is suited for the treatment of prostate cancer up to the clinical stage of T2a. MATERIAL AND METHODS: Some weeks before the implantation of the seeds the prostate volume is determined using transrectal ultrasound (TRUS) so as to estimate the required number of I-125 seeds. At the outset of the treatment the prostate is stabilized by two perineally inserted needles. Subsequently there is carried out an ultrasound guided treatment planning that allows to optimize the distribution of the seeds within the prostate. In interstitial brachytherapy we use RAPID STRANDS((R)), i. e. the I-125 seeds are embedded in vicryl suture at distances of 1 cm. During implantation of the I-125 seeds the transversal placement of the applicator needles is controlled by TRUS and the cranio-caudal placement of the applicator needles is controlled using the fluoroscopic unit as well as TRUS. About 4 weeks after the implantation of the seeds there is carried out a postoperative computation of the dose distribution of the implant using CT imaging. RESULTS: The procedure possesses the advantage that ultrasound imaging, treatment planning and seed implantation are carried out with the prostate remaining in an unaltered position. During implantation the combined imaging of TRUS and fluoroscopy allows a safe placement of the seeds with in the prostate. CONCLUSION: The methods for the calculation of the actually attained dose distribution must still be optimized, because the postoperative examination of the individual results has so far been possible only with difficulties resulting from methodological inconveniences.  相似文献   
103.

Purpose

Salvage radiotherapy (SRT) is applied routinely in patients with a biochemical relapse after radical prostatectomy (RP). Although the detection threshold for relapse after RP has steadily been lowered, only about 30 % of the SRT patients achieve a durable response. We have previously shown the association between a PSA decrease below detectable levels after SRT and biochemical progression-free survival (BPFS). After recalculating our data according to a more recent definition of biochemical failure after SRT, we now show the significance of the post-RP PSA nadir.

Materials and methods

Among 159 prostate cancer patients without hormonal treatment after RP, SRT was given to 72 patients with persistently detectable PSA after RP and to 87 whose PSA increased out of an undetectable range. The median pre-SRT PSA was 0.29 ng/ml for the former group and 0.34 ng/ml for the latter group. A radiation dose of 66.6 Gy was applied to the prostate bed.

Results

The overall median follow-up time was 41.7 months. The probability for BPFS after this period was 52.8 % in 72 patients with persistently detectable PSA after RP and 65.4 % in 87 patients who had a post-RP PSA nadir below detection limit. Univariate and multivariate analyses showed no significant difference in BPFS of both patient groups (p > 0.05).

Conclusion

Our findings suggest that SRT is a viable treatment option for patients with persistently detectable PSA, giving similar results as in patients whose PSA increases out of an undetectable range after RP.  相似文献   
104.
Acoustic stimulation evokes about 15 waves, the so-called auditory evoked potentials (AEP). According to their appearance in time there are three groups: early auditory evoked potentials, middle latency AEP and late latency AEP. The shorter the latency of a wave, the more precise the coordination to a definable structure in the CNS. Therefore only EAEP allow besides an evaluation of hearing threshold a differential diagnosis between peripheral, neural and central hearing disturbances. Still unclear are questions such as exact origin of waves II to V and the difference of response due to rarefaction and condensation stimuli. The test, however, is a sensitive indicator to evaluate hearing disturbances and brainstem disorders.  相似文献   
105.

Purpose

Our objective was to compare open and endovascular aortic aneurysm repair with respect to postoperative delirium.

Methods

After Institutional Ethics Review Board approval, we conducted a retrospective review of all patients who underwent abdominal and thoraco-abdominal aortic aneurysm repair surgery at Toronto General Hospital during June 2006 to December 2007. Patients were classed into either the OPEN or the endovascular (EVAR) group based on the type of surgery and were assessed for the presence of delirium after surgery. The NEECHAM Confusion Scale and the validated chart review instrument were used for diagnosis of delirium. Patients with dementia and/or abnormal levels of consciousness preoperatively were excluded.

Results

There were 256 patients included in the study, 149 (58%) in the OPEN group and 107 (42%) in the EVAR group. Patients in the EVAR group were considerably older, 74 (10) yr vs 68 (9) yr, and they had shorter duration of surgery, 150 [119, 180] min vs 200 [165, 260] min, respectively, P?<?0.0001. Postoperative delirium was present in 43 (29%) patients in the OPEN group and 14 (13%) patients in the EVAR group (95% confidence interval [CI], 22 to 36 vs 95% CI, 7 to 19, respectively; P?=?0.003). Hospital length of stay was 8.3 [6.6, 13.4] days in the OPEN group and 4.5 [3.1, 6.4] days in the EVAR group, P?<?0.0001.

Conclusions

Perioperative management of patients undergoing endovascular aortic aneurysm repair was associated with lower rates of delirium after surgery than that of patients undergoing open aortic aneurysm repair.  相似文献   
106.
107.
Reduced tolerance of steatotic livers to ischemic injury is considered to correlate with impaired microcirculation. The aim of this study was to investigate the impact of heat-shock preconditioning (HSPC) on microcirculatory failure after ischemia/reperfusion (I/R) in steatotic livers by means of intra-vital fluorescence microscopy. Obese Zucker rats were used. In the HS group, rats underwent whole-body hyperthermia followed by 60-min partial liver ischemia. In group IR, rats were exposed only to ischemia. Microcirculation parameters (sinusoidal perfusion rate, sinusoidal diameter, leukocyte-endothelial interaction) were significantly better preserved in the HS group than in the IR group. Liver enzymes, oxygenated glutathione/reduced glutathione (GSSG/GSH) ratio, and electron microscopy showed less damage in the HS group. A marked expression of heat shock protein 72 (HSP72) and heme oxygenase (HO-1) was found only in the livers of group HS. HSPC mitigated the I/R injury of steatotic livers by preventing post-ischemic failure of microcirculation. This beneficial effect was found to be associated with the induction of HSP72 and HO-1.  相似文献   
108.
BACKGROUND: High-dose chemotherapy followed by autologous blood stem cell transplantation induces remission of plasma cell dyscrasia in patients with AL amyloidosis. The impact of this treatment on the glomerular amyloid mass is still unknown. METHODS: In the present study, the quantity of the renal amyloid mass before and more than 3 years after high-dose melphalan treatment and autologous blood stem cell transplantation was assessed in two patients. At the time of the second renal biopsy, both patients were in complete remission without detectable serum and urinary monoclonal IgA-lambda and a normal percentage of plasma cells in the bone marrow. RESULTS: In both patients with biopsy-proven AL amyloidosis, urinary protein excretion decreased from 7 g/24 h to <2 g/24 h more than 3 years after autologous blood stem cell transplantation. In contrast, glomerular amyloid deposits persisted, as shown in the second biopsy. CONCLUSION: Despite complete remission of the plasma cell dyscrasia and improvement of glomerular permeability, the amount of glomerular amyloid mass did not regress.  相似文献   
109.
BACKGROUND: Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS: Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS: Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS: Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation.  相似文献   
110.
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