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1.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Akteure der öffentlichen Gesundheit (Public Health) tragen wesentlich zu Gesundheitsschutz, -förderung und...  相似文献   
2.

Background

Available models for predicting lymph node invasion (LNI) in prostate cancer (PCa) patients undergoing radical prostatectomy (RP) might not be applicable to men diagnosed via magnetic resonance imaging (MRI)-targeted biopsies.

Objective

To assess the accuracy of available tools to predict LNI and to develop a novel model for men diagnosed via MRI-targeted biopsies.

Design, setting, and participants

A total of 497 patients diagnosed via MRI-targeted biopsies and treated with RP and extended pelvic lymph node dissection (ePLND) at five institutions were retrospectively identified.

Outcome measurements and statistical analyses

Three available models predicting LNI were evaluated using the area under the receiver operating characteristic curve (AUC), calibration plots, and decision curve analyses. A nomogram predicting LNI was developed and internally validated.

Results and limitations

Overall, 62 patients (12.5%) had LNI. The median number of nodes removed was 15. The AUC for the Briganti 2012, Briganti 2017, and MSKCC nomograms was 82%, 82%, and 81%, respectively, and their calibration characteristics were suboptimal. A model including PSA, clinical stage and maximum diameter of the index lesion on multiparametric MRI (mpMRI), grade group on targeted biopsy, and the presence of clinically significant PCa on concomitant systematic biopsy had an AUC of 86% and represented the basis for a coefficient-based nomogram. This tool exhibited a higher AUC and higher net benefit compared to available models developed using standard biopsies. Using a cutoff of 7%, 244 ePLNDs (57%) would be spared and a lower number of LNIs would be missed compared to available nomograms (1.6% vs 4.6% vs 4.5% vs 4.2% for the new nomogram vs Briganti 2012 vs Briganti 2017 vs MSKCC).

Conclusions

Available models predicting LNI are characterized by suboptimal accuracy and clinical net benefit for patients diagnosed via MRI-targeted biopsies. A novel nomogram including mpMRI and MRI-targeted biopsy data should be used to identify candidates for ePLND in this setting.

Patient summary

We developed the first nomogram to predict lymph node invasion (LNI) in prostate cancer patients diagnosed via magnetic resonance imaging-targeted biopsy undergoing radical prostatectomy. Adoption of this model to identify candidates for extended pelvic lymph node dissection could avoid up to 60% of these procedures at the cost of missing only 1.6% patients with LNI.  相似文献   
3.
Six patients who injured their wrists had radiographs documenting a dorsal, 5- to 10-mm oblong fragment of bone immediately proximal to the base of the fourth and/or fifth metacarpal bones. The fragment was seen on the pronation oblique and/or lateral projections, but not on the posteroanterior projection. The radiographic appearance of the fragment was remarkably similar in all cases. In the one patient in which it was performed, pluridirectional tomography demonstrated that the fragment originated from the dorsal surface of the hamate. Five of the six patients also had associated posterior dislocation of the fourth and/or fifth metacarpals. We conclude that this fragment represents a coronal fracture through the body of the hamate resulting from posterior dislocation or subluxation of the fourth and/or fifth metacarpal.  相似文献   
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Growth of malignant tumors is dependent on sufficient blood supply. Thus, inhibition of tumor angiogenesis is emerging as a promising target in the treatment of malignancies. Human angiostatin (hANG) is one of the most potent inhibitors of endothelial cell proliferation, angiogenesis, and tumor growth in vivo. However, its mechanisms operating in vivo are not well understood. METHODS: To obtain more information about functional changes in the angiogenic process, we established Morris hepatoma (MH3924A) cell lines expressing hANG (hANG-MH3924A). The effects of hANG expression on proliferation and apoptosis of human umbilical vein endothelial cells (HUVECs) were measured in coculture experiments in vitro. To evaluate changes in tumor perfusion and blood volume, H2 15O and 68Ga-DOTA-albumin (DOTA is 1,4,7,10-tetraazacyclododecane-N,N',N',N'-tetraacetic acid) were used for PET studies in vivo. Additionally, immunohistologic quantification of vascularization, apoptosis, and proliferation as well as gene array analyses were performed. RESULTS: Our in vitro experiments demonstrate reduced proliferation and increased apoptosis in HUVECs when being cocultured with hANG-MH3924A. In support, tumor growth of hANG-MH3924A is diminished by 95% in vivo. However, tumor perfusion and blood volume are increased in hANG-MH3924A corresponding to an increased microvessel density. Furthermore, hANG-transfected tumors show changes in expression of genes related to apoptosis, stress, signal transduction, and metabolism. CONCLUSION: hANG expression leads to inhibition of tumor growth, increased apoptosis, and changes in the expression of multiple genes involved in stress reactions, signal transduction, and apoptosis, which indicates a multifactorial reaction of tumors. An enhanced microvessel density is seen as part of these reactions and is associated with increased perfusion as measured by PET.  相似文献   
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The influence of metabolic control (HbA1c), noradrenaline (NA) and insulin-like growth factors (IGF-I and IGF-II) on renal function and size was investigated in 11 insulin-dependent diabetes mellitus patients aged 11–17 years. Renal function was evaluated in terms of glomerular filtration rate (GFR) and effective renal plasma flow (ERPF). Renal size was determined as renal parenchymal volume (RPV) by ultrasonography. The patients' HbA1c values ranged from 8.2% to 12.9% (normal range 5.5–8.5%) and their GFR and ERPF were higher than normal. Their IGF-II values were higher, and NA and IGF-I levels were lower than those of healthy controls. Inverse correlations between NA and GFR (r=–0.66) and NA and ERPF (r=–0.63) were found. No correlation was found between serum IGF-I and renal functional parameters. The IGF-II values correlated with GFR and HbA1c (r=0.63,r=0.70 respectively). There were linear correlations between RPV and GFR, RPV and ERPF, HbA1c and GFR, and ERPF and RPV. Decreased NA concentrations and increased IGF-II values appear to be factors contributing to renal hyperfunction in these patients.  相似文献   
9.
目的评价β-受体阻滞剂治疗老年冠心病慢性心力衰竭的疗效及安全性。方法105例老年冠心病慢性心力衰竭患者按就诊顺序随机分为两组,美托洛尔组52例在常规抗心力衰竭治疗基础上加用美托洛尔12.5~25mg,2/d;对照组53例采用常规抗心力衰竭治疗,未用美托洛尔。定期来诊随访,观察临床表现,监测治疗前后心率、血压、心功能参数变化。结果美托洛尔组显效率53.8%,总有效率88.5%;对照组显效率30.2%,总有效率67.9%,两者比较有显著性差异(P〈0.05)。美托洛尔组患者心率减慢、血压降低较对照组明显,超声心动图复查显示治疗6个月后左室舒张末期内径缩小,左室射血分数增高较对照组显著。结论美托洛尔为老年冠心病慢性心力衰竭提供一种较为安全有效的药物治疗手段。  相似文献   
10.
BACKGROUND AND PURPOSE: Following preoperative radiotherapy prior to ablative surgery of squamous epithelial cell carcinomas of the head and neck region, wound-healing disorders occur. Previous experimental studies showed altered expression of transforming growth factor-(TGF-)beta isoforms following surgery in irradiated graft beds. Altered levels of TGF-beta(1) are reported to promote fibrosis and to suppress vascularization during wound healing, whereas expression of TGF-beta receptor-III (TGF-betaR-III) is associated with vascularization. The aim of the study was to analyze the influence of anti-TGF-beta(1) treatment on TGF-betaR-III-associated vascularization in the transition area between irradiated graft bed and graft. MATERIAL AND METHODS: Wistar rats (male, weight 300-500 g) underwent preoperative irradiation of the head and neck region with 40 Gy (four fractions of 10 Gy each; n = 16 animals). A free myocutaneous gracilis flap taken from the groin was then transplanted to the neck in all rats. The time interval between operation and transplantation was 4 weeks. Eight animals received 1 micro g anti-TGF-beta(1) into the graft bed by intradermal injection on days 1-7 after surgery. On days 3, 7, 14, 28, 56, and 120, skin samples were taken from the transition area between transplant and graft bed and from the graft bed itself. Immunohistochemistry was performed using the ABC-POX method to analyze the TGF-betaR-III and E-selectin expression. Histomorphometry was performed to analyze the percentage and the area of positively stained vessels. RESULTS: A significantly higher expression of TGF-betaR-III was seen in the irradiated and anti-TGF-beta(1)-treated graft bed in comparison to the group receiving preoperative irradiation followed by transplantation alone. The percentage of TGF-betaR-III positively staining capillaries from the total amount of capillaries in the anti-TGF-beta(1)-treated graft bed was higher than in the group irradiated only. The total area of capillaries was also higher in the TGF-beta(1)-treated group. CONCLUSION: Neutralizing of TGF-beta(1) activity in irradiated tissue undergoing surgery leads to a higher expression of TGF-betaR-III and increased vascularization. TGF-betaR-III seems to be associated with newly formed blood vessels during neovascularization in wound healing.  相似文献   
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