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91.

Introduction

The therapy of esophageal perforation is still challenging. The aim of this study was to assess the etiology, specific treatment, and outcome of esophageal disruption in order to generate an optimal therapeutic approach to improve patient’s outcome.

Methods

We reviewed the cases of 120 consecutive patients with esophageal perforation treated within 10 years.

Results

Iatrogenic perforation was the most frequent cause of esophageal perforation (58.3 %); Boerhaave’s syndrome was detected in 15 cases (6.8 %). Surgery was performed in 66 patients (55 %), 17 (14 %) patients received conservative treatment and 37 (31 %) patients underwent endoscopic stenting after tumorous perforation. Statistically significant impact on mean survival had Boerhaave’s syndrome (p?=?0.005), initial sepsis (p?=?0.002), pleural effusion/empyema (p?=?0.001), mediastinitis (p?=?0.003), peritonitis (p?=?0.001), and redo-surgery (p?=?0.000). Overall mortality rate was 11.7 %, in the esophagectomy group 17 % and in the patients with Boerhaave’s syndrome 33.3 %.

Conclusions

An approach considering etiology and extent of perforation, diagnostic delay, and septic status is required to improve patient’s outcome. Primary repair is feasible in patients without intrinsic esophageal disease and evidence of sepsis. The greater the diagnostic delay, the more the destruction of the esophageal wall especially in the case of septic esophageal disease, thus the stronger the argument for esophagectomy if anatomically and/or oncologically possible.  相似文献   
92.

Background

Heterotopic ossification (HO) is a common complication following orthopedic and trauma surgery, which may have substantial negative effects on the postoperative outcome. Angiogenesis appears to play a critical role in heterotopic ossification. One of the involved signaling molecules is platelet-derived growth factor (PDGF) which may be inhibited by imatinib.

Questions/Purposes

Our goal was to prevent HO by pharmacologically interfering with the molecular signaling pathways involved in the developmental process. We hypothesized that by administering a proven inhibitor of PDGF expression, heterotopic bone formation may be prevented.

Methods

The effect of imatinib on HO formation was studied in a murine model which reliably produces islets of HO within the soft tissue following Achilles tenotomy. The control group underwent Achilles tenotomy only. The imatinib group received imatinib mesylate. After trial completion, the limbs were harvested and scanned by micro-CT. Heterotopic bone volume was then identified and quantified.

Results

The mean volume of heterotopic bone formed in the control group was 0.976mm3 compared to 0.221 mm3 in the imatinib group. The volume of HO in the treatment group was reduced by 85% compared to the control group.

Conclusions

The administration of imatinib was associated with a significantly reduced volume of HO. This may be due to the inhibitory effect of imatinib on the PDGF signaling pathway during development of HO.

Clinical Relevance

The successful reduction of HO formation following imatinib administration has led to further insight concerning the pathogenesis of HO which in the future may lead to new clinical approaches towards the prevention of HO.

Electronic supplementary material

The online version of this article (doi:10.1007/s11420-013-9335-y) contains supplementary material, which is available to authorized users.  相似文献   
93.
94.
Histopathological analysis can provide important information in long‐term experiments with total artificial heart (TAH). Recently, a new type of blood pump, the helical flow total artificial heart (HF‐TAH) was developed. This study aimed to investigate the changes in selected vital organs in animal experiments with implanted HF‐TAH. Samples from lung, liver, and kidneys from two female goats (No. 1301 and No. 1304) with implanted HF‐TAH were analyzed. Tissue samples were fixed in 10% formaldehyde and 4 µm thick transverse sections were stained with hematoxylin‐eosin (HE). Additional staining was done for detection of connective tissue (Masson‐Goldner stain) and for detection of iron (hemosiderin) deposits (Perls stain). Sections were scanned at 100× and 500× magnification with a light microscope. Experiment no. 1301 survived 100 days (cause of termination was heavy damage of the right pump); experimental goat no.1304 survived 68 days and was sacrificed due to severe right hydrodynamic bearing malfunction. Histopathological analysis of liver samples proved signs of chronic venostasis with limited focal necrotic zones. Dilated tubules, proteinaceous material in tubular lumen, and hemosiderin deposits were detected in kidney samples. Contamination of the organs by embolized micro‐particles was suspected at the autopsy after discovery of visible damage (scratches) of the pump impeller surface (made from titanium alloy) in both experiments. Sporadic deposits of foreign micro‐particles (presumably titanium) were observed in most of the analyzed parenchymal organs. However, the described deposits were not in direct connection with inflammatory reactions in the analyzed tissues. Histopathological analysis showed the presence of minimal contamination of the lung, kidney, and liver tissue samples by foreign material (titanium very likely). The analysis showed only limited pathological changes, especially in liver and kidneys, which might be attributed to the influence of artificial perfusion often observed in chronic TAH experiments.  相似文献   
95.
B cells play an important role in the immune responses which affect the outcomes of kidney allografts. Dynamic changes of B‐cell compartments in clinical kidney transplantation are still poorly understood. B‐cell subsets were prospectively monitored using flow cytometry for 1 year in 98 kidney transplant recipients. Data were correlated with immunosuppression and clinical outcomes. An increase in the total population of B lymphocytes was observed during the first week after transplantation. The level of IgMhighCD38highCD24high transitional B cells reduced significantly up until the third month, with partial repopulation in the first year. Lower numbers of transitional B cells in the third month were associated with higher risk of graft rejection. IgM+IgD+CD27? naive B cells did not change within follow‐up. IgM+CD27+ nonswitched memory B cells and IgM?CD27+ switched memory B cells increased on post‐operative day 7. IgM?CD38highCD27high plasmablasts showed similar kinetics during the first post‐transplant year, similar to transitional B cells. In conclusion, sensitized kidney transplant recipients as well as those with either acute or chronic rejection within the first post‐transplant year exhibited lower levels of transitional B cells. Therefore, these data further support the hypothesis that transitional B cells have a protective role in kidney transplantation.  相似文献   
96.
Patients with acute leukemias of undifferentiated lineage (AUL) generally have guarded prognosis. Here, we describe the first reported pediatric patient with AUL refractory to high‐dose chemotherapy who achieved clinical remission with ALL maintenance therapy and 5‐azacitidine. His induction remission was followed by consolidation with reduced toxicity haploidentical hematopoietic stem cell transplant (HSCT). At 9 months post‐HSCT, the patient is alive and in remission. This combination therapy of remission induction with ALL maintenance therapy and 5‐azacitidine and consolidation with reduced toxicity haploidentical HSCT is novel and promising for patients who lack conventional donors and are not candidates for myeloablative therapy.  相似文献   
97.
Intraneuronal alpha-synuclein (alphaSYN) inclusions constitute the hallmark lesions of a number of neurodegenerative diseases, including Parkinson's disease and dementia with Lewy bodies. In a transgenic mouse model expressing mutant [A30P]alphaSYN under control of the pan-neuronal Thy1 promoter, motor impairment became significant beyond 17 months of age. Cognitive performance was measured in the Morris water maze and upon fear conditioning. At 4 months of age, transgenic mice performed like controls. However, performance in these tasks was significantly impaired in (Thy1)-h[A30P]alphaSYN mice at 12 months of age. After completion of the cognition tests, mice were sacrificed and the regional distribution of neuropathology was examined. In contrast to 4 months old animals, 12 months old transgenic mice showed alpha-synucleinopathy in several brain regions, including the central nucleus of the amygdala, which is involved in cognitive behavior of mice, and is susceptible to alphaSYN pathology in human patients. Thus, age-dependent fibrillization of alphaSYN in specific cortical regions concomitant with cognitive decline may reflect dementia with Lewy bodies in a transgenic mouse model.  相似文献   
98.

Background

Long-term exposure to ambient air pollution contributes to the global burden of disease by particularly affecting cardiovascular (CV) causes of death. We investigated the association between particle number concentration (PNC), a marker for ultrafine particles, and other air pollutants and high sensitivity C-reactive protein (hs-CRP) as a potential link between air pollution and CV disease.

Methods

We cross-sectionally analysed data from the second follow up (2013 and 2014) of the German KORA baseline survey which was conducted in 1999–2001. Residential long-term exposure to PNC and various other size fractions of particulate matter (PM10 with size of <10?μm in aerodynamic diameter, PMcoarse 2.5–10?μm or PM2.5?<?2.5?μm, respectively), soot (PM2.5abs: absorbance of PM2.5), nitrogen oxides (nitrogen dioxide NO2 or oxides NOx, respectively) and ozone (O3) were estimated by land-use regression models. Associations between annual air pollution concentrations and hs-CRP were modeled in 2252 participants using linear regression models adjusted for several confounders. Potential effect-modifiers were examined by interaction terms and two-pollutant models were calculated for pollutants with Spearman inter-correlation <0.70.

Results

Single pollutant models for PNC, PM10, PMcoarse, PM2.5abs, NO2 and NOx showed positive but non-significant associations with hs-CRP. For PNC, an interquartile range (2000 particles/cm3) increase was associated with a 3.6% (95% CI: ?0.9%, 8.3%) increase in hs-CRP. A null association was found for PM2.5. Effect estimates were higher for women, non‐obese participants, for participants without diabetes and without a history of cardiovascular disease whereas ex-smokers showed lower estimates compared to smokers or non-smokers. For O3, the dose-response function suggested a non-linear relationship. In two-pollutant models, adjustment for PM2.5 strengthened the effect estimates for PNC and PM10 (6.3% increase per 2000 particles/cm3 [95% CI: 0.4%; 12.5%] and 7.3% per 16.5?μg/m3 [95% CI: 0.4%; 14.8%], respectively).

Conclusion

This study adds to a scarce but growing body of literature showing associations between long-term exposure to ultrafine particles and hs-CRP, one of the most intensely studied blood biomarkers for cardiovascular health. Our results highlight the role of ultrafine particles within the complex mixture of ambient air pollution and their inflammatory potential.  相似文献   
99.
100.
To study the effect of hip and pelvis geometry on development of the hip after Perthes disease, we determined the resultant hip force and contact hip stress distribution in a population of 135 adult hips of patients who had been treated for Perthes disease in childhood. Contra‐lateral hips with no record of disease were taken as the control population. Biomechanical parameters were determined by mathematical models for resultant hip force in one‐legged stance and for contact hip stress, which use as an input the geometrical parameters assessed from anteroposterior radiographs. The mathematical model for stress was upgraded to account for the deviation of the femoral head shape from spherical. No differences were found in resultant hip force and in peak contact hip stress between the hips that were in childhood subject to Perthes disease and the control population, but a considerable (148%) and significant (p < 0.001) difference was found in the contact hip stress gradient index, expressing an unfavorable, steep decrease of contact stress at the lateral acetabular rim. This finding indicates an increased risk of early coxarthritis in hips subject to Perthes disease. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:8–16, 2014.  相似文献   
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