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391.
392.
Clodronate inhibits adrenocortical cell proliferation and P450c21 activity   总被引:1,自引:0,他引:1  
Bisphosphonates (BPs), specific inhibitors of osteoclasts, are well established in the management of skeletal metastases in breast cancer. Recent studies have suggested that these compounds may also directly influence tumor cell proliferation. As adrenocortical cancer frequently leads to bone metastases, we investigated the effects of clodronate (CLO) in the human adrenocortical cancer cell line NCI-H295 and in primary cultures of bovine adrenocortical cells. Both the non-amino BP CLO and the amino BP pamidronate (PAM) exhibited a dose-dependent antiproliferative effect in both cell types (cell viability in NCI-H295 cells: 100 microM CLO: 98+/-8%; 500 microM CLO 76+/-6%; 1000 microM CLO 53+/-2; 10 microM PAM 96+/-3%; 50 microM PAM 46+/-6%; 100 microM PAM 11+/-1% vs untreated control cells: 100+/-10%; P<0.01). FACS analysis in NCI-H295 cells treated with either CLO or PAM demonstrated both apoptotic and necrotic cell death. However, while during PAM treatment cell number and hormone secretion decreased in parallel, we observed specific impairment of steroidogenesis in the presence of CLO with a dose-dependent increase in the 17-OH-progesterone/cortisol ratio (100 microM CLO 134+/-30%; 500 microM CLO 284+/-10%; 1000 microM CLO 545+/-130% vs 100+/-20% in control cells; P<0.01). Further analysis in ACTH-stimulated bovine adrenal cells using stable isotope dilution/gas chromatography-mass spectrometry demonstrated CLO-induced inhibition of adrenal 21-hydroxylase (P450c21) activity leading to a dose-dependent increase in the 17-OH-progesterone/11-deoxycortisol ratio. In conclusion, we demonstrate a dose-dependent antiproliferative effect of CLO and PAM in adrenocortical cells. In addition, for the first time, we describe a suppressive effect of CLO on steroidogenesis via inhibition of adrenal 21-hydroxylase (P450c21) activity.  相似文献   
393.
Background: To evaluate gastric compared with small bowel feeding on nutrition and clinical outcomes in critically ill, neurologically injured patients. Materials and Methods: International, prospective observational studies involving 353 intensive care units (ICUs) were included. Eligible patients were critically ill, mechanically ventilated with neurological diagnoses who remained in the ICU and received enteral nutrition (EN) exclusively for at least 3 days. Sites provided data, including patient characteristics, nutrition practices, and 60‐day outcomes. Patients receiving gastric or small bowel feeding were compared. Covariates including age, sex, body mass index, and Acute Physiology and Chronic Health Evaluation II score were used in the adjusted analyses. Results: Of the 1691 patients who met our inclusion criteria, 1407 (94.1%) received gastric feeding and 88 (5.9%) received small bowel feeding. Adequacy of calories from EN was highest in the gastric group (60.2% and 52.3%, respectively, unadjusted analysis; P = .001), but this was not significant in the adjusted model (P = .428). The likelihood of EN interruptions due to gastrointestinal (GI) complications was higher for the gastric group (19.6% vs 4.7%, unadjusted model; P = .015). There were no significant differences in the rate of discontinuation of mechanical ventilation (hazard ratio [HR], 0.86; 95% confidence interval [CI], 0.66–1.12; P = .270) or the rate of being discharged alive from the ICU (HR, 0.94; 95% CI, 0.72–1.23; P = .641) and hospital (HR, 1.16; 95% CI, 0.87–1.55; P = .307) after adjusting for confounders. Conclusions: Despite a higher likelihood of EN interruptions due to GI complications, gastric feeding may be associated with better nutrition adequacy, but neither route is associated with better clinical outcomes.  相似文献   
394.
Obesity is a major chronic disease affecting the U.S. population. Bariatric surgery has consistently shown greater weight loss and improved outcomes compared with conservative therapy. However, complications after bariatric surgery can be catastrophic, resulting in short bowel syndrome with a potential risk of intestinal failure, ultimately resulting in the need for a small bowel transplant. A total of 6 patients became dependent on home parenteral nutrition (HPN) after undergoing bariatric surgery at an outside facility. Four of the 6 patients required evaluation for small bowel transplant; 2 of the 6 patients were successfully managed with parenteral nutrition and did not require further small bowel transplant evaluation. Catheter‐related bloodstream infection, a serious complication of HPN, occurred in 3 patients despite extensive patient education on catheter care and use of ethanol lock. Two patients underwent successful small bowel transplantation, 1 died before transplant could be performed, and 1 was listed for a multivisceral transplantation. Surgical procedures to treat morbid obesity are common and growing in popularity but are not without risk of serious complications, including intestinal failure and HPN dependency. Despite methods to prevent complications, failure of HPN may lead to the need for transplant evaluation. In selected cases, the best therapeutic treatment may be a small bowel transplant to resolve irreversible, post–bariatric surgery intestinal failure.  相似文献   
395.
Derivatives of etomidate were evaluated as inhibitors of adrenal steroid 11beta-hydroxylations. Stereoselective coupling by Mitsunobu produced chirally pure analogues to study the effect of configuration, modification of the ester, and substitution in the phenyl ring, with the aim to probe specific sites for introducing a radionuclide. Iodophenyl metomidate (IMTO) labeled with iodine-131 served as radioligand for structure-affinity relationship studies. We have characterized the kinetic parameters of specific (131)I-IMTO binding on rat adrenal membranes and used the displacement of (131)I-IMTO binding to evaluate functionalized MTO analogues. Our results indicated that (1) ( R)-configuration is essential for high affinity, (2) highest potency resides in the ethyl, 2-propyl, and 2-fluoroethyl esters, and (3) substitution of the phenyl ring is well tolerated. The clinically used inhibitors metyrapone and ketoconazole inhibited (131)I-IMTO binding with low affinity. Incubation of selected analogues with human adrenocortical NCI-h295 cells demonstrated a high correlation with the inhibitory effect on cortisol secretion.  相似文献   
396.
Adrenocortical carcinoma (ACC) has a dismal prognosis in advanced stages. Despite treatment with the adrenal toxicant mitotane and/or aggressive chemotherapy, tumor control is often short-lived. Here, we examine trofosfamide as a salvage treatment of ACC in an observational cohort study within the German ACC registry. Response defined as progression-free survival (PFS) at first tumor evaluation was assessed by RECIST 1.1 or clinically, and PFS and overall survival (OS) were estimated by the Kaplan-Meier method. Twenty-seven patients (11 males; median age 46.9 years) progressing after mitotane and three (median, range 0–5) other systemic treatments were evaluated for safety. Trofosfamide (150 mg/day) was administered as monotherapy (n?=?13) or in combination with mitotane (n?=?14). Overall tolerability was good with only mild adverse events. Six patients did not meet criteria for response assessment. Of the 21 patients, 8 patients had clinically progressive disease (3 deaths from ACC); among the 13 patients evaluable by RECIST 1.1, best response to treatment was stable disease (SD, n?=?3) or progressive disease (n?=?10). Hence, predefined response criteria were met in 3/21 patients (14 %). Median PFS was 84 days (95 % confidence interval 74–95) and median OS survival 198 days (95 % CI 89–307). One prolonged disease stabilization (best response by RECIST 1.1 ?26 %) was observed for 479 days. In conclusion, trofosfamide is overall well tolerated but disease stabilization is rather rare. Accordingly, it may be used in selected cases of ACC not amenable to other treatment options such as clinical trials.  相似文献   
397.
Piro  LD; Carrera  CJ; Beutler  E; Carson  DA 《Blood》1988,72(3):1069-1073
2-Chlorodeoxyadenosine, a new lymphocyte-selective, anti-neoplastic drug was administered to 18 patients with advanced chronic lymphocytic leukemia of B-cell origin. All patients were resistant to conventional treatment. A total of 44 courses of 2-chlorodeoxyadenosine were completed with minimal toxicity. An overall response rate of 55% was achieved with four of 18 patients demonstrating partial response and six of 18 patients experiencing clinical improvement. Only minor bone marrow suppression occurred during administration of the drug, indicating a high degree of lymphocyte selectivity. Reduction of lymphocyte infiltration in bone marrow occurred in treated patients including one patient who experienced normalization of the bone marrow. Three of four patients with concurrent autoimmune hemolytic anemia experienced resolution of hemolysis, as indicated by elimination of transfusion requirement, fall in reticulocyte count, elevation of hemoglobin, and ability to taper prednisone without recurrence of hemolysis. Duration of responses ranged from 2 to 15 months without maintenance therapy.  相似文献   
398.
CONTEXT: Adrenocortical carcinoma (ACC) is a rare malignancy with poor prognosis. In advanced disease, mitotane given as monotherapy or combined either with etoposide, doxorubicin, and cisplatin or with streptozotocin is the recommended first-line therapy. However, many patients have progressive disease despite treatment with these regimens. OBJECTIVE: Our objective was to evaluate the efficacy of the epidermal growth factor receptor inhibitor erlotinib plus gemcitabine as salvage therapy in ACC patients with very advanced ACC. DESIGN/SETTING: The study consisted of case series collected from different centers (primary care and referral centers) in Germany in 2006-2007. PATIENTS AND INTERVENTION: Patients registered with the German ACC Registry with progressive ACC after two to four previous systemic therapies were offered treatment with erlotinib and gemcitabine. Oral erlotinib (100 mg/d) was administered on a daily basis and gemcitabine (800 mg/m(2)) iv every 14 d. MAIN OUTCOME MEASURE: We evaluated tumor response according to response evaluation criteria in solid tumors (RECIST) criteria after 12 wk of treatment. RESULTS: Ten patients have been treated with erlotinib and gemcitabine. Only one in 10 patients experienced a minor response (progression-free survival 8 months), whereas eight patients had progressive disease at the first staging. One patient had to stop therapy after the first administration of gemcitabine due to cerebral seizure. Nine of 10 patients had died after a median of 5.5 months after treatment initiation. In addition to the seizure, one patient experienced severe pneumonia (grade III), and in one, gemcitabine administration had been delayed due to prolonged neutropenia. All other adverse events were mild (grade I-II). CONCLUSIONS: Salvage chemotherapy using erlotinib plus gemcitabine has very limited to no activity in patients with very advanced ACC.  相似文献   
399.
BACKGROUND: Alloimmunization to red cell antigens is a significant risk in chronically transfused patients with sickle cell disease. Antigen matching, by decreasing the likelihood of alloantibody development, may significantly facilitate long-term management while decreasing morbidity. STUDY DESIGN AND METHODS: The transfusion records of 86 patients who underwent chronic transfusion for sickle cell disease at a tertiary-care medical center were reviewed retrospectively to determine the efficacy of an antigen-matching program in the prevention of alloimmunization to clinically significant red cell antigens. Recipients were phenotyped and given units matched for the K, C, E, S, and Fya or Fyb antigens. RESULTS: None (0%) of the 40 patients who received antigen-matched transfusions showed any evidence of alloimmunization, while 16 (34.8%) of the 46 patients who received both antigen-matched and non-antigen-matched transfusions developed clinically significant alloantibodies. The cost was 1.8 to 1.5 times that for a standard transfusion protocol. CONCLUSION: On the basis of this experience, it is recommended that transfusion centers engaged in the management of chronically transfused sickle cell anemia patients consider providing antigen-matched units for such patients. This is recommended not only because it prevents alloimmunization but also because such a program provides additional clinical benefits to the patient that may outweigh the higher costs of the process.  相似文献   
400.
Abstract. Healthy infants and children were found to excrete bile alcohol glucuronides in urine. Following isolation and hydrolysis, the bile alcohols were estimated by capillary gas-liquid chromatography. The daily urinary excretion of the major compound, 27-nor-5 β -cholestane-3α,7α,12α,24ξ,25ξ-pentol (a C26 bile alcohol), ranged from 0·1 to 1·1 μmol/24 h per m2 body surface area for healthy infants and children. Two groups of patients with α1-antitrypsin deficiency (phenotype PiZ) were also studied during infancy and childhood, and biochemical liver function tests and liver morphology were compared to the excretion of bile alcohols. The highest excretion of the C26 bile alcohol in urine was found in patients with α1-antitrypsin deficiency and juvenile cirrhosis (2·1–8·4 μmol 24 h-1 m-2) regardless of preceding neonatal cholestasis. Patients with α1-antitrypsin deficiency, neonatal cholestasis and subsequent fibrosis or normal liver morphology excreted bile alcohols within the normal range. The C26 bile alochol constituted an average of 36% of the total bile alcohols in forty-three urine samples. This percentage was about the same in the three groups studied. The findings suggest that determination of urinary bile alcohols may be a valuable non-invasive diagnostic tool for patients with or at risk of developing liver cirrhosis.  相似文献   
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