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91.
The outcome of ischemic acute renal failure (IARF) is better in young than adult rats. Insulin-like growth factor I (IGF-I) treatment may increase mortality of adult rats with IARF, probably because of an exaggerated inflammatory response. We report the response to IGF-I therapy in young rats with IARF. Male rats, aged 28+/-1 days, with IARF were given subcutaneous IGF-I, 50 microg/100 g at 0, 8, and 16 h after reperfusion (IGF) or were untreated (ARF). Sham-operated rats were used as controls. At 2 and 7 days after ischemia, serum urea nitrogen and histological damage score, cell proliferation, apoptosis, neutrophil infiltration, and IGF-I receptor mRNA in kidneys were analyzed. The degree of renal failure, mortality rate, histological damage, cell proliferation, and neutrophil infiltration were not different between IGF-I and ARF rats. Hence, short-term IGF-I treatment did not modify the course of IARF in young rats.  相似文献   
92.

Background

The need for axillary lymph node dissection (ALND) in breast cancer patients with sentinel lymph node (SLN) micrometastases remains controversial. The aims of the study were to evaluate the locoregional failure and outcome of breast cancer patients with sentinel node micrometastases who did not undergo completion ALND.

Methods

Between November 2000 and December 2006, SLN biopsy was successfully performed in 1178 patients with invasive breast carcinoma. Only patients with macrometastasis (>2 mm) underwent ALND, while patients with negative SLN or micrometastases did not undergo further treatment of the axilla, by either surgery or radiotherapy. Regarding adjuvant therapy decision, patients with SLN-micrometastases (pN1mi) were considered as node-positive patients.

Results

Of 1,178 patients, 59 (5%) had micrometastases. Of those with micrometastases, 14 (24%) underwent ALND because the intraoperative study of the SLN yielded a positive result. With a median follow-up of 60 (range, 8–94) months, none of the patients with SLN micrometastases in whom ALND was omitted developed an axillary recurrence, while one patient in whom ALND was performed developed infraclavicular lymph node recurrence. One patient, who declined postoperative breast irradiation, developed breast recurrence and distant metastasis.

Conclusions

Breast cancer patients with SLN micrometastases in whom ALND was omitted had a very low locoregional failure rate. This study supports the theory that ALND might be avoided in these patients, providing that adjuvant systemic treatment equal to treatment provided to treat node-positive disease is administered. However, longer follow-up and results of additional prospective studies are needed.  相似文献   
93.
To obtain a new model of chronic portal hypertension in the rat, two classical methods to produce portal hypertension, partial portal vein ligation and the oral administration of thioacetamide (TAA), have been combined. Male Wistar rats were divided into four groups: 1 (control; n?=?10), 2 [triple partial portal vein ligation (TPVL); n?=?9], 3 (TAA; n?=?11), and 4 (TPVL plus TAA; n?=?9). After 3 months, portal pressure, types of portosystemic collateral circulation, laboratory hepatic function tests (aspartate aminotransferase, alanine aminotransferase, bilirubin, alkaline phosphatase, and gamma-glutamyl transpeptidase) and liver histology were studied. The animals belonging to group 2 (TPVL) developed extrahepatic portosystemic collateral circulation, associated with mesenteric venous vasculopathy without hepatic destructurization or portal hypertension. Animals from group 3 (TAA) developed cirrhosis and portal hypertension but not extrahepatic portosystemic collateral circulation, or mesenteric venous vasculopathy. Finally, the animals from group 4 (TPVL?+?TAA) developed cirrhosis, portal hypertension, portosystemic collateral circulation, and mesenteric venous vasculopathy. The association of TPVL and TAA can be used to obtain a model of chronic portal hypertension in the rat that includes all the alterations that patients with hepatic cirrhosis usually have. This could, therefore, prove to be a useful tool to study the pathophysiological mechanisms involved in these alterations.  相似文献   
94.
Hyponatremia is a significant complication of treatment with serotonin selective reuptake inhibitors (SSRI). We describe a case of a 53-year-old woman that was started on fluoxetine 20 mg/day for depression. Nine days later, the patient started with weakness, nausea, progressing to confusion, inappetence and vomit. Three hours later she became unresponsive and had a generalized seizure. She was brought to our emergency service. On admission, the patient was normovolemic, without focal motor deficits, but had mild generalized muscle rigidity and Babinski's sign bilaterally. Serum sodium was 105 mmol/L, serum osmolality, 220 mmol/L, and urinary osmolality, 400 mmol/L. The other laboratory exams, chest X-ray, cerebrospinal fluid and cranium tomography were normal. She was found to have fluoxetine-induced SIADH and it was discontinued. We started the hyponatremia correction and, in 5 days, the mental status of the patient gradually returned to a normal baseline, paralleling the resolution of her hyponatremia, without recurrence. Hyponatremia and SIADH should be considered if a patient experiences deterioration in his or her clinical condition while taking SSRI. The use of SSRI antidepressants should be remembered in the differential diagnosis of drug-induced hyponatremia.  相似文献   
95.
96.
Recent genome-wide association studies identified single-nucleotide polymorphisms (SNPs) in the gene encoding the pore-forming subunit of the voltage-gated K+ channel (KCNQ1) as a risk factor for type 2 diabetes. Tacrolimus (Tac) increased the risk of new-onset diabetes after transplantation (NODAT). The aim of this study was to analyze the association between KCNQ1 variants and the risk for NODAT in kidney-transplanted patients who received Tac as primary immunosuppressor. We genotyped three common KCNQ1 SNPs in 145 Spanish patients who received a cadaveric kidney graft and developed NODAT in the first-year post-transplant (the NODAT group), and 260 patients who remained non-diabetics (non-NODAT). In addition, we searched for DNA variants in the whole KCNQ1 coding exons in these patients. SNP rs2237895 (genotype CC) was associated with an increased risk for NODAT in our population (p = 0.008; OR = 1.83, 95% CI = 1.14-2.93), independently of other risk factors as body mass index, recipient age, or tacrolimus dosage. Other KCNQ1 variants were not associated with NODAT in our patients. Our work supported a role for KCNQ1 gene variants as determinants of the risk of developing NODAT among Tac-treated patients.  相似文献   
97.
This prospective, comparative trial investigated the impact on mean change in height standard deviation score (SDS), acute rejection rate, and renal function of early steroid withdrawal in 96 recipients with 5 years of follow-up. Recipients under basiliximab induction and steroid withdrawal (SW: TAC/MMF; n = 55) were compared with a matched steroid control group (SC: TAC/MMF/STEROID, n = 41). SW received steroids until Day 6, SC decreased to 10 mg/m(2) within 2 months post-transplant. Five years after SW, the longitudinal growth (SDS) gain was 1.4 ± 0.4 vs. 1.1 ± 0.3 for SC group (p < 0.02). Height benefits in prepubertal and pubertal status in both groups were demonstrated in the delta growth trends (mixed model; p < 0.01). Biopsy-proven acute rejection in SW was 11% and 17.5%, SC (p: ns). Mean eGFR (ml/min/1.73 m(2)) at 5 years post-transplant was SW 80.6 ± 27.8 vs. 82.6 ± 25.1 for SC (p: ns). The death-censored graft survival rate at 1 and 5 years was 99 and 90% for SW; 98 and 96% for SC (p = ns). PTLD incidence in SW 3.3 vs. 2.5% in SC (p: ns). Five years post-transplant, early steroid withdrawal showed positive impacts on growth, stable renal function without increased acute rejection risk, and PTLD incidence.  相似文献   
98.
Heterotopic pancreas is a rare congenital disorder characterized by the presence of normal pancreatic tissue located outside the pancreas. The most common locations include the duodenum, stomach, and jejunum. Most cases of heterotopic pancreas are asymptomatic. However, the development of clinical symptoms depends on the size, location and pathological changes similar to those observed in case of the normal pancreas. The Authors presented a case of multiple stomach heterotopic pancreatic lesions in an adult male patient. The atypical clinical presentation including non-specific endoscopic and CT images were responsible for the misdiagnosis before surgery. The patient underwent surgery. The tumor located in the posterior wall of the body of the stomach was excised by wedge resection. The postoperative course proved uneventful. Proper diagnosis was established on the basis of the histopathological examination of the resected tumor: heterotopic pancreas-multiple lesions, type II, according to Heinrich. The presented case report demonstrated that heterotopic pancreas should always be considered in the differential diagnosis of gastric tumors.  相似文献   
99.
BACKGROUND: Haemodynamic impairments after pneumonectomy are rare complications and present in different forms. Due to a low awareness of these potential complications their diagnosis is difficult and often established late. The most important forms are: firstly reopening of a previously closed foramen ovale (PFO) caused by a combination of changed anatomic position of the left atrium and elevated pulmonary artery pressure leading to a significant right-left shunt; secondly diaphragmatic relaxation can lead to a dislocation of the liver into the right hemithorax, compressing the right atrium with subsequent inflow obstruction. METHODS: We retrospectively analysed our patient cohort from 1997 to 2006 for occurrence of haemodynamic complications requiring surgical intervention after pneumonectomy. RESULTS: Five hundred and forty-six pneumonectomies were performed in our centre during the observation period. Five patients (1 female, 4 male, age 59+/-9 years) with haemodynamic complications were identified. Two of those patients were referred with haemodynamic complications after pneumonectomy was performed in a peripheral centre. All patients had undergone right pneumonectomy for NSCLC (n=4) or atypical carcinoid (n=1). Two patients were readmitted 3 months and 2 years postoperatively due to increasing platypnoea and orthodeoxia. After closure of the reopened foramen ovale, which was found as the underlying pathological mechanism, respiratory symptoms were resolved. One patient required reintubation 2h postoperatively; after surgical closure of a PFO the respiratory situation significantly improved. One patient was readmitted due to right atrial inflow obstruction 17 months after right pneumonectomy. Underlying cause was a severe diaphragmatic relaxation with compression of the atrium by the liver. After diaphragmatic plication all symptoms resolved. However 1 year thereafter reoperation for recurrence of diaphragmatic elevation was required. One patient was readmitted 3 months after pneumonectomy and partial atrial resection for cyanosis and dyspnoea. Diagnostics revealed a PFO and a massive raise of the right diaphragm with compression of the right atrium. After surgical correction of the contorted foramen ovale and diaphragmatic plication, symptoms vanished. CONCLUSION: Haemodynamic alterations due to a reopened foramen ovale or right atrial inflow obstruction are rare, however they are severe complications after pneumonectomy. They occur at variable points in time after pneumonectomy. Diagnostic efforts are often made at a late stage due to a low awareness of the problem. Closure of the PFO either surgical or interventional and/or plication of the elevated diaphragm are mandatory. In our experience these complications occur only after right pneumonectomy.  相似文献   
100.
BACKGROUND: Antagonists of growth hormone-releasing hormone (GHRH) could extend the duration of response of androgen sensitive prostate cancers to androgen deprivation. METHODS: We investigated the effect of new GHRH antagonists MZ-J-7-118 and MZ-J-7-138 and luteinizing hormone-releasing hormone (LHRH) antagonist Cetrorelix or castration on androgen sensitive MDA-PCa-2b and LuCaP-35 prostate cancer models xenografted into nude mice. Animals bearing androgen-independent LuCaP-35V prostatic cancer model were also treated with MZ-J-7-118. RESULTS: Receptors for LHRH and GHRH were present in MDA-PCA-2b, LuCaP-35, and LuCaP-35V tumors. GHRH antagonists increased the inhibitory effect of surgical castration and LHRH antagonists on androgen sensitive MDA-PCa-2b and LuCaP-35 tumors. The time to relapse of androgen-dependent LuCaP-35 tumors was extended by GHRH antagonists. Growth of androgen-independent LuCaP-35V xenografts was also significantly inhibited by MZ-J-7-118. In MDA-PCa-2b tumors treatment with MZ-J-7-118 caused a significant decrease of VEGF and Cetrorelix or its combination with MZ-J-7-118 reduced EGF. The B(max) of EGF receptors was significantly reduced by Cetrorelix, MZ-J-7-118 and their combination. CONCLUSIONS: Our findings suggest that the use of a combination of antagonists of GHRH and LHRH could improve the therapy for androgen sensitive prostate cancer. Antagonists of GHRH could be also considered for treatment of androgen-independent prostate cancers.  相似文献   
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