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991.
The introduction of molecular‐targeted therapy has made dramatical changes to treatment for metastatic renal cell carcinoma. Currently, there are four vascular endothelial growth factor receptor‐tyrosine kinase inhibitors and two mammalian target of rapamycin inhibitors in Japan. For the appropriate clinical use of these molecular‐targeted drugs, the identification of prognostic and/or predictive factors in patients who received these drugs is required. Although molecular biological and genetic factors that determine the prognosis of patients with metastatic renal cell carcinoma have been reported, most of these factors are problematic in that the number of patients analyzed was small. In contrast, clinicopathological prognostic factors, including the practice of cytoreductive nephrectomy, pathological findings, metastatic sites and metastasectomy, and abnormal inflammatory response, have been identified by analyzing a relatively large number of patients. Several prognostic classification models that were developed by combining these clinicopathological factors are widely used in not only clinical trials, but also routine clinical practice. However, the quality of these prognostic models is considered to be insufficient regarding prognostic prediction of metastatic renal cell carcinoma patients and, thus, requires further improvements. Recently, basic and clinical studies have been extensively carried out for the identification of promising informative markers and for understanding molecular mechanisms of resistance to molecular‐targeted drugs in metastatic renal cell carcinoma patients. The present review considers ongoing translational research efforts on clinicopathological, molecular biological, and genetic prognostic and/or predictive factors for metastatic renal cell carcinoma patients in the era of molecular‐targeted therapy, and discusses the clinical implications of these findings.  相似文献   
992.
993.

Background

Dabigatran etexilate, a new oral anticoagulant, was recently approved as an efficacious alternative to warfarin for the prevention of first and recurrent stroke in patients with nonvalvular atrial fibrillation. Limited data are available for dabigatran use in patients with a creatinine clearance rate (CrCL) of 15-30 mL/min. Furthermore, current guidelines do not recommend frequent blood monitoring after dabigatran use. We report herein a patient with severe renal dysfunction who exhibited profound coagulopathy after 2 days of dabigatran use.

Case Report

An 87-year-old woman was admitted for altered mental status and left-side weakness. She was diagnosed with right middle cerebral artery infarction. The baseline assessment revealed a serum creatinine concentration of 1.29 mg/dL and a CrCL of 27.2 mL/min. Dabigatran therapy was started 5 weeks after admission at a dosage of 110 mg twice daily. After 2 days of dabigatran use, the patient developed multiple bruises and evidence of upper-gastrointestinal bleeding. Laboratory tests demonstrated a severe coagulopathy, with a prothrombin time of 85.9 sec, an international normalized ratio of 11.36, an activated partial thromboplastin time of 119.2 sec, and a thrombin time of 230.8 sec. Serial assessment of the patient''s renal function revealed substantial fluctuation of the CrCL (range, 17.9-26.5 mL/min).

Conclusions

The present case emphasizes the need for frequent checking of renal function and assessment using coagulation assays after commencing dabigatran therapy in patients with moderate-to-severe renal impairment.  相似文献   
994.
Chronic renal failure (CRF) is associated with oxidative stress that promotes production of reactive oxygen species (ROS). Melatonin, the chief secretory product of the pineal gland, was recently found to be a potent free radical scavenger and antioxidant. The aim of this study was to examine the role of melatonin in protecting the aorta, heart, corpus cavernosum, lung, diaphragm, and kidney tissues against oxidative damage in a rat model of CRF, which was induced by five of six nephrectomy. Male Wistar albino rats were randomly assigned to either the CRF group or the sham-operated control group, which had received saline or melatonin (10 mg/kg, i.p.) for 4 wk. CRF was evaluated by serum blood urea nitrogen (BUN) level and creatinine measurements. Aorta and corporeal tissues were used for contractility studies, or stored along with heart, lung, diaphragm, and kidney tissues for the measurement of malondialdehyde (MDA, an index of lipid peroxidation), protein carbonylation (PC, an index for protein oxidation), and glutathione (GSH) levels (a key antioxidant). Plasma MDA, PC, and GSH levels and erythrocytic superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities were studied to evaluate the changes of antioxidant status in CRF. In the CRF group, the contraction and the relaxation of aorta and corpus cavernosum samples decreased significantly compared with controls (P < 0.05-0.001). Melatonin treatment of the CRF group restored these responses. In the CRF group, there were significant increases in tissue MDA and PC levels in all tissues with marked reductions in GSH levels compared with controls (P < 0.05-0.001). In the plasma, while MDA and PC levels increased, GSH, SOD, CAT, and GSH-Px activities were reduced. Melatonin treatment reversed these effects as well. In this study, the increase in MDA and PC levels and the concomitant decrease in GSH levels of tissues and plasma and also SOD, CAT, GSH-Px activities of plasma demonstrate the role of oxidative mechanisms in CRF-induced tissue damage, and melatonin, via its free radical scavenging and antioxidant properties, ameliorates oxidative organ injury. CRF-induced dysfunction of the aorta and corpus cavernosum of rats was reversed by melatonin treatment. Thus, supplementing CRF patients with adjuvant therapy of melatonin may have some benefit.  相似文献   
995.
The present study was designed to explore if maternal subtotal (5/6) nephrectomy affects the development of fetal rat kidneys using morphometric methods and examining whether there are any apoptotic changes in the fetal kidney. To generate 5/6 nephrectomized model rats, animals underwent 2/3 left nephrectomy on gestation day (GD) 5 and total right nephrectomy on GD 12. The fetal kidneys were examined on GDs 16 and 22. A significant decrease in fetal body weight resulting from maternal 5/6 nephrectomy was observed on GD 16, and a significant decrease in fetal renal weight and fetal body weight caused by maternal nephrectomy was observed on GD 22. Maternal 5/6 nephrectomy induced a significant increase in glomerular number, proximal tubular length, and total proximal tubular volume of fetuses on GD 22. Maternal 5/6 nephrectomy resulted in an increase in the number of apoptotic cells in the metanephric mesenchyme of the kidney on GD 16, and in the collecting tubules on GD 22. These findings suggest that maternal 5/6 nephrectomy stimulates the development of the fetal kidney while suppressing fetal growth.  相似文献   
996.
Summary The influence of different protein intake on renal function was studied in 16 Type 1 (insulin-dependent) diabetic patients, aged 15–23 years, with onset of diabetes before puberty and with a duration of diabetes between 5 and 20 years. The glomerular filtration rate, renal plasma flow, albumin excretion rate, and blood pressure were examined in a cross-over randomised order after 10 days on isocaloric diets with either 10% (i.e. 0.9±0.06 g·kg–1·day–1) or 20% (1.9±0.1 g·kg–1·day–1) of the calories as protein, the latter being equal to the recommended diet. Dietary compliance was evaluated using fractional phosphate excretion and overnight urea excretion. Glomerular filtration rate was lower after the low-protein diet compared to the usual protein diet (p<0.001). Patients with glomerular filtration rate above +2 SD of the normal mean on the usual protein diet (n=6) exhibited the steepest fall in glomerular filtration rate with a mean decrease of 20ml/min compared to 7 ml/min in those with initially normal glomerular filtration (p=0.01). Filtration fraction tended to decrease on low protein diet, more so in initially hyperfiltering patients (p=0.09). Renal plasma flow remained unchanged. In patients with elevated glomerular filtration rate on usual protein diet, albumin excretion rate and systolic, but not diastolic blood pressure, were decreased on low protein diet (p=0.03 and p=0.01, respectively) but not in initially normal-filtering patients. Mean blood glucose and serum fructosamine were unchanged on both diets. In conclusion, low protein diet decreases glomerular filtration rate independently of glycaemic control in young Type 1 diabetic patients and more so in hyperfiltering patients. This decline in glomerular filtration rate is accompanied by a decrease in albumin excretion rate and systolic blood pressure in hyper-filtering patients.  相似文献   
997.
Gallbladder involvement in patients with renal cell carcinoma (RCC) is extremely rare. We present a report of a 61-year-old man with a synchronous RCC metastasis to the gallbladder presenting as an intraluminal polypoid mass simulating primary gallbladder carcinoma. Enhanced abdominal computed tomography demonstrated a well-enhanced polypoid lesion in the gallbladder. Intraoperative rapid pathological examination of the gallbladder tumor showed clear cell-type cancerous cells. Microscopically, tumor cells of both the resected kidney and gallbladder had round uniform nuclei, clear cytoplasm, and well-defined cytoplasmic borders, forming alveolar patterns. Immunohistochemically, the tumor cells were negative for cytokeratin 7 (CK7) and carcinoembryonic antigen (CEA), which is usually positive in primary clear cell carcinoma of the gallbladder. Therefore, the final diagnosis was RCC with a synchronous gallbladder metastasis.  相似文献   
998.
BackgroundThe American College of Cardiology Interventional Council published consensus-based recommendations to help identify resuscitated cardiac arrest patients with unfavorable clinical features in whom invasive procedures are unlikely to improve survival.ObjectivesThis study sought to identify how many unfavorable features are required before prognosis is significantly worsened and which features are most impactful in predicting prognosis.MethodsUsing the INTCAR (International Cardiac Arrest Registry), the impact of each proposed “unfavorable feature” on survival to hospital discharge was individually analyzed. Logistic regression was performed to assess the association of such unfavorable features with poor outcomes.ResultsSeven unfavorable features (of 10 total) were captured in 2,508 patients successfully resuscitated after cardiac arrest (ongoing cardiopulmonary resuscitation and noncardiac etiology were exclusion criteria in our registry). Chronic kidney disease was used in lieu of end-stage renal disease. In total, 39% survived to hospital discharge. The odds ratio (OR) of survival to hospital discharge for each unfavorable feature was as follows: age >85 years OR: 0.30 (95% CI: 0.15 to 0.61), time-to-ROSC >30 min OR: 0.30 (95% CI: 0.23 to 0.39), nonshockable rhythm OR: 0.39 (95% CI: 0.29 to 0.54), no bystander cardiopulmonary resuscitation OR: 0.49 (95% CI: 0.38 to 0.64), lactate >7 mmol/l OR: 0.50 (95% CI: 0.40 to 0.63), unwitnessed arrest OR: 0.58 (95% CI: 0.44 to 0.78), pH <7.2 OR: 0.78 (95% CI: 0.63 to 0.98), and chronic kidney disease OR: 0.96 (95% CI: 0.70 to 1.33). The presence of any 3 or more unfavorable features predicted <40% survival. Presence of the 3 strongest risk factors (age >85 years, time-to-ROSC >30 min, and non-ventricular tachycardia/ventricular fibrillation) together or ≥6 unfavorable features predicted a ≤10% chance of survival to discharge.ConclusionsPatients successfully resuscitated from cardiac arrest with 6 or more unfavorable features have a poor long-term prognosis. Delaying or even forgoing invasive procedures in such patients is reasonable.  相似文献   
999.
OBJECTIVES: The incidence of gastroduodenal diseases is high in patients with chronic renal failure (CRF). However, gastric acidity in CRF has been reported to range in level from low to high. Moreover, it remains unknown whether Helicobacter pylori infection influences gastric acidity in such patients. Thus, we aimed to clarify the pathophysiological perturbation in gastric acidity and to determine the influence of H. pylori infection in CRF. DESIGN: Case-control study. SETTING: A university hospital. SUBJECTS: Twenty-seven patients with CRF and 24 control patients, presenting with either gastrointestinal symptoms, positive faecal occult blood, or anaemia (haemoglobin <10 g dL(-1)). MEASURES: The patients underwent gastroduodenal endoscopy with simultaneous determination of H. pylori infection. Gastric ammonium concentration, serum pepsinogen I and II, and basal gastrin level were measured. Thereafter, gastric acid secretion was monitored by 24-h intragastric acidity measurement with calculation of pH-3 holding time (%) (hours showing pH>3/24 h). RESULTS: In the CRF group, pH-3 holding time of H. pylori (+) subgroup was significantly greater than that of H. pylori (-) subgroup (71.2 +/- 32.4% vs. 32.8 +/- 30.0%, mean +/- SD; P=0.03). Pepsinogen I/II ratio was inversely correlated with pH-3 holding time in the control and CRF groups. Gastric ammonium concentration in CRF/H. pylori (+) subgroup (14.1 +/- 9.2 mmol L(-1)) was significantly higher than in CRF/H. pylori (-) (2.5 +/- 2.7 mmol L(-1); P=0.002) and control/H. pylori (+) subgroups (6.1 +/- 4.2 mmol L(-1); P=0.01). Serum gastrin level was significantly higher in the CRF group than in the control group (297 +/-343 pg mL(-1) vs. 116 +/- 69 pg mL(-1); P=0.02) as a whole. However, there was no significant correlation between serum creatinine and gastrin levels in the CRF group. Gastrin level in CRF/H. pylori (+) subgroup was significantly higher than in CRF/H. pylori (-), control/H. pylori (+), and control/H. pylori (-) subgroups (423 +/-398 pg mL(-1) vs. 113 +/- 79, 124 +/- 78, and 96 +/-43 pg mL(-1), respectively; P=0.01-0.03). Significant positive correlations amongst pH-3 holding time, ammonium and gastrin concentrations were found in the CRF group, but not in the control group. CONCLUSIONS: CRF without H. pylori infection primarily shows a tendency for high gastric acidity, but without hypergastrinaemia. Persistent H. pylori infection in CRF leads to decreased acidity and, consequently, to fasting hypergastrinaemia via a feedback mechanism. The hypoacidity in CRF with H. pylori infection appears to result from neutralization of acid by ammonia as well as from gastric atrophy. Thus, H. pylori infection status critically determines perturbation in gastric acidity and fasting gastrin level in CRF.  相似文献   
1000.
Henoch-Schonlein purpura (HSP) is the most common acute vasculitis in the pediatric population, with an incidence of 10-14 per 100,000. The classic presentation of this disorder includes erythematous papules followed by palpable purpura in the lower extremities, trunk, and face, arthralgia or arthritis, abdominal pain, gastrointestinal bleeding, and nephritis. While renal abnormalities in HSP are common, the classic pulmonary manifestations, such as hemorrhage and pneumonitis, are thought to be infrequent. Subclinical pulmonary manifestations, including diffusion defects and radiographic anomalies, seem to be quite frequent in patients with HSP but are not commonly reported. Other respiratory manifestations include pleural effusion and chylothorax, but these are rarely mentioned in the literature. Chylothorax was only reported once in an adult patient with HSP in whom the mechanism of formation was demonstrated to be secondary to transdiaphragmatic passage of chylous fluid from the peritoneal cavity. Here we describe an 8-year-old girl with HSP, nephrotic syndrome, and chylothorax, and we report the results of a review of the literature regarding respiratory complications in HSP. The present case is the first pediatric patient reported with HSP and chylothorax. The therapeutic measures utilized were effective in resolving her edema, ascites, and chylothorax, and we advocate the use of these measures as first-line therapy in future patients with similar complications from HSP.  相似文献   
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