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61.
Wozakowska-Kapłon B  Opolski G  Janion M  Kosior D 《Kardiologia polska》2004,61(12):513-21; discussion 522
BACKGROUND: Plasma concentration of atrial natriuretic peptide (ANP) is elevated in patients with atrial fibrillation (AF) and in patients with chronic heart failure (CHF).Aim. To assess ANP level in patients with permanent AF and advanced CHF. METHODS: The study group consisted of 41 patients (27 males, mean age 62+/-8 years) with AF of a mean duration of 8.8 months. Twenty six (63%) patients were in NYHA class II, and 15 (37%) - in NYHA class III or IV. All patients underwent clinical and echocardiographic evaluation as well as ANP plasma concentration assessment. Multiple regression analysis was used to identify factors which determine ANP plasma concentration. RESULTS: Mean ANP plasma concentration was 52.4+/-22.7 pg/ml in the whole study group; 38.6+/-10.8 pg/ml in NYHA class II patients and 74.9+/-18.7 pg/ml in NYHA class III-IV subjects (p<0.0001). Among echocardiographic parameters, patients with NYHA class III or IV had significantly lower left ventricular ejection fraction and greater left atrial volume than patients with NYHA class II (32% versus 56%, p<0.0001 and 101.0+/-23.8 cm(3) versus 83.4+/-16.1 cm(3), p<0.006, respectively). Multiple regression analysis revealed a significant negative correlation between AF duration and ANP level (p=0.0013) in a group of patients with NYHA class III or IV and identified AF duration as an independent predictor of ANP plasma concentration in this group of patients. CONCLUSIONS: ANP plasma concentration in patients with persistent AF and advanced CHF is determined by AF duration - the longer the AF duration the lower the ANP level.  相似文献   
62.
Endoscopy being a diagnostic tool, allows also a nonsurgical treatment of upper gastrointestinal tract neoplasms, even at their advanced stage. Argon plasma coagulation (APC) is a contact-free method of monopolar coagulation, based primarily on the effects of high frequency electrical current flow in the ionized argon. The study used in 14 patients, aged 56-85 years, with advanced carcinoma of oesophagus and/or cardia. Carcinoma was diagnosed upon the results of endoscopic and microscopic examinations. The following parameters were included in the analysis: electrical current power, number of treatment sessions, stage of dysphagia, oesophagus passage, localization and type of a tumor. The analysis revealed that APC is a highly effective as well as safe method of palliative treatment of advanced oesophageal and/or cardiac cancers. Moreover, it was noted that APC is more effective in adenocarcinomas than in squamous cell carcinomas.  相似文献   
63.
BACKGROUND/AIMS: The pathogenesis of pancreatic fibrosis is unknown. Pathogenic analyses take into account the effect of oxidant stress and the increase in free radicals leading to degranulation of mast cells, which may cause inflammation and activate fibrosis. Activated pancreatic stellate cells produce abnormal components of intercellular substance and are responsible for pancreatic fibrogenesis. The aim of the study was to determine the correlation between the presence and state of mast cells and pancreatic stellate cells activation in chronic pancreatitis with varied intensity fibrosis. METHODOLOGY: We studied 27 patients with chronic pancreatitis of varied fibrosis intensity. Immunohistochemical reactions for mast cells (anti-human mast cell tryptase) and ultrastructural analyses of mast cells and pancreatic stellate cells were performed. The number of degranulated mast cells in the ultrastructural picture and the number of pancreatic stellate cells stained positive for vimentin and alpha-smooth muscle actin were counted. RESULTS: A significant increase was revealed in the number of degranulated mast cells--to 35.6% in chronic pancreatitis I degree fibrosis, 68.3% in II degree, 75.1% in III degree and IV degree (control 10.2%) and a parallel increase in the number of activated pancreatic stellate cells (stained positive for alpha-smooth muscle actin) to 328 +/- 29/mm2 in I degree fibrosis, to 978 +/- 67/mm2 in II degree and 2355 +/- 331/mm2 in III degree and IV degree (control 38.8 +/- 9/mm2). CONCLUSIONS: The increase in the number of activated pancreatic stellate cells parallel to the increase in degranulated mast cells in more pronounced pancreatic fibrosis suggests that mast cell-released chemical mediators are involved in pancreatic stellate cells activation.  相似文献   
64.
Transepithelial water flow across the renal proximal tubule is mediated predominantly by aquaporin-1 (AQP1). Along this nephron segment, luminal delivery and transepithelial reabsorption are directly coupled, a phenomenon called glomerulotubular balance. We hypothesized that the surface expression of AQP1 is regulated by fluid shear stress, contributing to this effect. Consistent with this finding, we found that the abundance of AQP1 in brush border apical and basolateral membranes was augmented >2-fold by increasing luminal perfusion rates in isolated, microperfused proximal tubules for 15 minutes. Mouse kidneys with diminished endocytosis caused by a conditional deletion of megalin or the chloride channel ClC-5 had constitutively enhanced AQP1 abundance in the proximal tubule brush border membrane. In AQP1-transfected, cultured proximal tubule cells, fluid shear stress or the addition of cyclic nucleotides enhanced AQP1 surface expression and concomitantly diminished its ubiquitination. These effects were also associated with an elevated osmotic water permeability. In sum, we have shown that luminal surface expression of AQP1 in the proximal tubule brush border membrane is regulated in response to flow. Cellular trafficking, endocytosis, an intact endosomal compartment, and controlled protein stability are the likely prerequisites for AQP1 activation by enhanced tubular fluid shear stress, serving to maintain glomerulotubular balance.  相似文献   
65.
AIM: To determine whether ischemic preconditioning (IP) affects the development of edematous cerulein-induced pancreatitis and to assess the role of cyclooxygenase-1 (COX-1), COX-2, and heat shock protein 70 (HSP 70) in this process, METHODS: In male Wistar rats, IP was performed by clamping of celiac artery (twice for 5 min at 5-min intervals). Thirty minutes after IP or sham operation, acute pancreatitis was induced by cerulein. Activity of COX-1 or COX-2 was inhibited by resveratrol or rofecoxib, respectively (10 mg/kg). RESULTS: IP significantly reduced pancreatic damage in cerulein-induced pancreatitis as demonstrated by the improvement of pancreas histology, reduction in serum lipase and poly-C ribonuclease activity, and serum concentration of pro-inflammatory interleukin (IL)-lp. Also, IP attenuated the pancreatitis-evoked fall in pancreatic blood flow and pancreatic DNA synthesis. Serum level of anti-inflammatory IL-10 was not affected by IP. Cerulein-induced pancreatitis and IP increased the content of HSP 70 in the pancreas. Maximal increase in HSP 70 was observed when IP was combined with cerulein-induced pancreatitis. Inhibition of COXs, especially COX-2, reduced the protective effect of IP in edematous pancreatitis. CONCLUSION: Our results indicate that IP reduces pancreatic damage in cerulein-induced pancreatitis and this effect, at least in part, depends on the activity of COXs and pancreatic production of HSP 70.  相似文献   
66.

Aims

The level of C-peptide can identify individuals most likely to respond to immune interventions carried out to prevent pancreatic β-cell damage.The aim of the study was to evaluate factors associated with C-peptide levels at type 1 diabetes (T1D) diagnosis.

Methods

This study included 1098 children aged 2-17 with newly recognized T1D. Data were collected from seven Polish hospitals. The following variables were analyzed: date of birth, fasting C-peptide, HbA1c, sex, weight, height, pH at diabetes onset.

Results

A correlation was observed between fasting C-peptide level and BMI-SDS (p?=?0.0001), age (p?=?0.0001), and HbA1c (p?=?0.0001). The logistic regression model revealed that fasting C-peptide ≥0.7 ng/ml at diabetes diagnosis was dependent on weight, HbA1c, pH and sex (p?<?0.0001).Overweight and obese children (n?=?124) had higher fasting C-peptide (p?=?0.0001) and lower HbA1c (p?=?0.0008) levels than other subjects. Girls had higher fasting C-peptide (p?=?0.036) and higher HbA1c (p?=?0.026) levels than boys.

Conclusion

Obese and overweight children are diagnosed with diabetes at an early stage with largely preserved C-peptide levels. Increased awareness of T1D symptoms as well as improved screening and diagnostic tools are important to preserve C-peptide levels. There are noticeable gender differences in the course of diabetes already at T1D diagnosis.  相似文献   
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69.
The present work describes synthesis, characterization, and use of a new dansyl-labelled Ag@SiO2 nanocomposite as an element of a new plasmonic platform to enhance the fluorescence intensity. Keeping in mind that typical surface plasmon resonance (SPR) characteristics of silver nanoparticles coincide well enough with the absorption of dansyl molecules, we used them to build the core of the nanocomposite. Moreover, we utilized 10 nm amino-functionalized silica shell as a separator between silver nanoparticles and the dansyl dye to prevent the dye-to-metal energy transfer. The dansyl group was incorporated into Ag@SiO2 core-shell nanostructures by the reaction of aminopropyltrimethoxysilane with dansyl chloride and we characterized the new dansyl-labelled Ag@SiO2 nanocomposite using transmission electron microscopy (TEM) and Fourier-transform infrared spectroscopy (FTIR). Additionally, water wettability measurements (WWM) were carried out to assess the hydrophobicity and hydrophilicity of the studied surface. We found that the nanocomposite deposited on a semitransparent silver mirror strongly increased the fluorescence intensity of dansyl dye (about 87-fold) compared with the control sample on the glass, proving that the system is a perfect candidate for a sensitive plasmonic platform.  相似文献   
70.
Considering the increasing age of individuals affected with heart failure (HF), a specific approach to their treatment is required, with more attention paid to geriatric conditions such as poor mobility, multiple disabilities, and cognitive impairment. Frailty is a distinct biological syndrome reflecting decreased physiologic reserve and resistance to stressors. It was shown to occur frequently in patients with heart failure, with the prevalence ranging from 15 to 74 %, depending on the studied population and the method of assessment. We reviewed literature data on the influence of frailty, skeletal abnormalities, comorbidities and geriatric condition on diagnosis, treatment, and outcomes in elderly patients with HF. Identification of frailty in patients with HF is important from the clinical point of view, as this condition exerts unfavorable effects on the course of heart failure. Frailty contributes to a higher frequency of visits to emergency departments, hospitalizations, and mortality in patients with HF. Exercise may improve mobility, and nursing support can be implemented to help the patients adhere to medications. Therefore, frail patients should be diagnosed and treated according to available guidelines, and successfully educated about their condition.  相似文献   
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