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21.
BACKGROUND: Telomerase preserves telomeres' function and structure preventing cellular senescence. Its activity is reduced in peripheral blood mononuclear cells (PBMC) of haemodialysis (HD) patients. The purpose of this study is to investigate the potential correlation between increased oxidative stress/inflammation and telomerase activity in PBMC of HD patients. METHODS: Telomerase activity was measured by PCR-ELISA in PBMC isolated from a group of 42 HD patients and 39 subjects with estimated glomerular filtration rate >or=80 mL/min (control group). Serum oxidized low-density lipoprotein (ox-LDL), tumour necrosis factor-alpha (TNF-alpha) and interleukin-10 (IL-10) were also measured in both groups by ELISA. RESULTS: Ox-LDL was negatively correlated to percentage telomerase activity in PBMC (r = -0.506, P = 0.000 in the whole group of 81 HD and normal subjects and r = -0.559, P < 0.001 in HD patients). TNF was also inversely associated with percentage telomerase activity in the whole group studied (r = -0.492, P = 0.000) while IL-10 was not. In stepwise multiple linear regression, taking into consideration the most important characteristics of the HD patients and control group, the only significant predictors for percentage telomerase activity in PBMC were ox-LDL and TNF (beta = -0.421, t = -4.083, P = 0.000 and beta = -0.381, t = -3.691, P = 0.000, respectively) while examining separately HD patients, the predictors for the same parameter were ox-LDL and HD duration (beta = -0.671, t = -4.709, P = 0.000 and beta = -0.349, t = -2.447, P = 0.023, respectively). CONCLUSION: Ox-LDL serum level is inversely correlated to telomerase activity in PBMC of HD patients. Our study proposes a new consequence of increased oxidative stress in HD patients: the premature cellular senescence potentially related to atherosclerosis through LDL oxidation.  相似文献   
22.
Purpose: Presentation of the results of Tc-99m-sestamibi imaging in the pre-operative localization of parathyroid adenomas and the intra-operative localization of those lesions using a gamma detector (prospective study). Patients & methods: Eighteen consecutive patients aged 27-75 years with primary hyperparathyroidism (PHPT) underwent Tc-99m-sestamibi scanning 1-2 hours before the operation and the presence of a single adenoma was recognized. All our patients underwent bilateral neck exploration based on pre-operative scanning and intra-operative gamma detector guidance and the adenoma was detected in the positions shown by both methods.

Results: In 16 patients we found a single adenoma localized in the same position shown by pre-operative scanning, while the intra-operative method accurately revealed all abnormal glands. In one of the two patients where an inaccurate pre-operative localization technique had been carried out, we performed thyroid lobectomy (the adenoma proved to be intrathyroidal), while the other one had an adenoma which was not close to the site indicated by the pre-operative scintigraphy. Serum calcium reverted to normal within a few days postoperatively.

Conclusion: Patients with true-positive scans for single parathyroid adenoma could be eligible for minimally invasive operations since the abnormal gland is easily identified by the above-mentioned methods.  相似文献   
23.
ALZA and Crescendo are developing E-TRANS fentanyl, an electrotransport system (ETS) delivery offentanyl that allows self-titration of the drug by the patient, for the potential management of acute pain. The product was previously being developed in collaboration with Janssen, but by February 2000, Janssen was no longer involved in its development. In January 1998, Janssen, ALZA and Crescendo had plans to develop the product for the potential treatment of chronic pain in addition to the acute pain indication; however, no further development for this indication has been reported since that date. ETS is able to deliver drugs that normally would not diffuse across the skin. A small electric current passes through the patient's skin, between the two electrodes on the patch. Charged drug molecules are attracted to the electrode of the opposite polarity to their own. Manipulating the charge on drug molecules is relatively easy in most instances, so the technology should be applicable to the majority of drugs that do not lend themselves to passive diffusion. ETS technology is also potentially useful in delivering rapid boluses of drug on demand. In February 2000, Merrill Lynch predicted E-TRANS fentanyl sales at US $30 million in 2002, rising to US $131 million in 2004. Analysts at SG Cowen predicted in March 2001, that E-TRANS fentanyl would be rolled out during 2003 and that sales would reach US $40 to 50 million in 2004. In April 2001, Merrill Lynch predicted earliest launch in 2003.  相似文献   
24.
The aim of this uncontrolled, prospective, clinical study was to investigate the efficacy and safety of molgramostim administration in patients with severe sepsis. The subjects were 20 critically ill, mechanically ventilated patients with severe sepsis in a university intensive care unit (ICU). Molgramostim 300 microg s.c. was given every 12 h for 3 d. Treatment for severe sepsis was also administered as medically indicated. No adverse events (clinical or serum chemistry) were considered as drug related. Temperature (p = 0.334) and PaO2/FiO2 index (arterial oxygen tension/inspiratory oxygen fraction) (p = 0.178) were not significantly changed. Total leukocyte and neutrophil count increased significantly (p < 0.001) during drug administration. Simplified Acute Physiology Score II (SAPS II) was not significantly increased (p = 0.955), but there was a statistically significant decrease (p = 0.006) in Sepsis-related Organ Failure Assessment (SOFA) score. Death probability was not statistically different compared with mortality rate on day 28 and overall mortality (p = 0.238 and 0.700, respectively). There were statistically significant decreases (p < 0.01) in serum tumor necrosis factor-alpha (TNF-alpha), TNF-RII and interleukin-2 (IL-2), and an increase in TNF-RI levels between study entry and day 3. Mean ICU stay was 40.2 +/- 7.7 d. In conclusion, molgramostim administration may not affect serum chemistry and PaO2/FiO2 index, may decrease SOFA score but does not produce significant clinical benefit in terms of patients' outcome compared with death probability. It may also influence TNF-alpha, TNF-RI and TNF-RII serum complex levels. These changes may be attributed to the natural clinical course of sepsis or therapy applied.  相似文献   
25.
A case of acute granulomatous appendicitis due to Strongyloides stercoralis infection in an HIV-positive patient is described. To our knowledge this is the first case presented in the literature.  相似文献   
26.
Abstract:  The aim of the study was to assess the possible associations between allergies and type 1 diabetes mellitus (DM1), stratified by social class. We studied 127 children with DM1 with a median age of 10.8 yr and 150 controls of comparable age and sex distribution. The parents completed questionnaires on their education and occupation and on their children's history of allergic symptoms, breast-feeding, viral infections, and measles–mumps–rubella (MMR) vaccination. Lower family's social class was more frequently encountered among the DM1 families than in the controls (OR = 0.56, 95% CI: 0.35–0.92). The occurrence of any allergic symptoms among children with DM1 (35.45%) was not significantly different from the controls (38.78%), neither in the total group (OR = 0.87, 95% CI: 0.52–1.45) nor in the stratified analysis by social class. Similar findings were observed regarding the different types of allergic symptoms. In the univariate analysis, breast-feeding, the experience of viral infections, and MMR vaccination were found to be protective of DM1 presentation in both upper and lower social classes. In the multiple logistic regression analysis, the experience of more than 2 infections/yr (OR = 0.12, 95% CI: 0.04–0.34), the origin from middle and upper social classes (OR = 0.42, 95% CI: 0.22–0.80) and breast-feeding (OR = 0.58, 95% CI: 0.31–1.07) were protective of DM1 occurrence. In children with DM1, the presence of allergic symptoms was not associated with the development of DM1. Among the environmental factors, the origin from middle or upper social classes, breast-feeding, the experience of viral infections, and MMR vaccination were found to have a protective effect on DM1 presentation.  相似文献   
27.

Background

Tissue genomic heterogeneity (t-HET) in patients with epithelial ovarian cancer (OVCA) is related to tissue plasticity, i.e., flexibility to adapt to adverse molecular environments. Here, we interrogated the presence and clinical relevance of OVCA t-HET.

Methods

We applied high-depth (>2000×) sequencing on 297 paraffin tissue samples (fallopian tubes, ovaries, intra-abdominal metastases) from 71 treatment-naïve patients who subsequently received first-line platinum-based chemotherapy. Based on tissue mutation patterns, we distinguished tissue genotypes into: no mutation (33/297 samples; 11.1%), stable (173; 58.2%) and unstable (91; 30.7%). We profiled genotypes per patient and assessed t-HET in 69 patients. Predicted pathogenic mutations refer to germline and/or tissues.

Results

Among all 71 patients, 46 (64.8%) had pathogenic BRCA1 mutations and 15 (21.7%) had BRCA1/2 disruption (i.e., pathogenic mutations with position-LOH). We classified 29 patients with t-HET (42%), all with pathogenic BRCA1; t-HET was observed in 64% with such mutations (p?<?0.001). As opposed to non-t-HET, matched tissues in t-HET shared pathogenic BRCA1 (p?<?0.001) but not BRCA2 and TP53. Germline BRCA1 mutations in tissues exhibited position-LOH; heterozygous status; or, partial loss of the inherited allele accompanied by additional clonal mutations. Patients with t-HET had worse outcome (log-rank p?=?0.048 [progression-free]; p?=?0.037 [overall survival]), including 12/15 patients with disrupted BRCA1/2 and 3 BRCA1 carriers with partial germline loss in tissues.

Conclusions

Pathogenic BRCA1 mutations appear necessary but may not be sufficient for the establishment of t-HET. t-HET may be associated with worse outcome, including in patients with disrupted BRCA1/2, which is usually considered as a favourable marker. OVCA t-HET may need to be addressed for treatment decisions.  相似文献   
28.
Although the medial prefrontal cortex (mPFC) plays a critical role in cocaine addiction, the effects of chronic cocaine on mPFC neurons remain poorly understood. Here, we performed visualized current-clamp recordings to determine the effects of repeated cocaine administration on the membrane excitability of mPFC pyramidal neurons in rat brain slices. Following repeated cocaine administration (15 mg/kg/day i.p. for 5 days) with a 3-day withdrawal, alterations in membrane properties, including increased input resistance, reduced intensity of intracellular injected currents required for generation of Na(+)-dependent spikes (rheobase), and an increased number of spikes evoked by depolarizing current pulses were observed in mPFC neurons. The current-voltage relationship was also altered in cocaine-pretreated neurons showing reduced outward rectification during membrane depolarization and decreased inward rectification during membrane hyperpolarization. Application of the K(+) channel blocker Ba(2+) depolarized the resting membrane potential (RMP) and enhanced membrane potential response to injection of hyperpolarizing current pulses. However, the effects of Ba(2+) on RMP and hyperpolarized membrane potentials were significantly attenuated in cocaine-withdrawn neurons compared with saline-pretreated cells. These findings indicate that repeated cocaine administration increased the excitability of mPFC neurons after a short-term withdrawal, possibly via reducing the activity of the potassium inward rectifiers (K(ir)) and voltage-gated K(+) currents. Similar changes were also observed in cocaine-pretreated mPFC neurons after a long-term (2-3 weeks) withdrawal, revealing a persistent increase in excitability. These alterations in mPFC neuronal excitability may contribute to the development of behavioral sensitization and withdrawal effects following chronic cocaine exposure.  相似文献   
29.
30.
The purpose of this work is to provide some statistical methods for evaluating the predictive strength of radiobiological models and the validity of dose-response parameters for tumour control and normal tissue complications. This is accomplished by associating the expected complication rates, which are calculated using different models, with the clinical follow-up records. These methods are applied to 77 patients who received radiation treatment for head and neck cancer and 85 patients who were treated for arteriovenous malformation (AVM). The three-dimensional dose distribution delivered to esophagus and AVM nidus and the clinical follow-up results were available for each patient. Dose-response parameters derived by a maximum likelihood fitting were used as a reference to evaluate their compatibility with the examined treatment methodologies. The impact of the parameter uncertainties on the dose-response curves is demonstrated. The clinical utilization of the radiobiological parameters is illustrated. The radiobiological models (relative seriality and linear Poisson) and the reference parameters are validated to prove their suitability in reproducing the treatment outcome pattern of the patient material studied (through the probability of finding a worse fit, area under the ROC curve and chi2 test). The analysis was carried out for the upper 5 cm of the esophagus (proximal esophagus) where all the strictures are formed, and the total volume of AVM. The estimated confidence intervals of the dose-response curves appear to have a significant supporting role on their clinical implementation and use.  相似文献   
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