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991.
The influence of early feeding on the risk of atopic diseases has been studied in full-term newborns, not in very low birth weight infants (VLBW). The study evaluated effect of early feeding of VLBW infants with either cow's milk-based formula (CMF) or extensively hydrolyzed milk formula (HF) on incidence of atopic diseases and markers of atopy at 5-7 years of age. This was a follow-up of the randomized, double-blind study evaluating the influence of different enteral feeding protocols on the early morbidity of VLBW infants. In the original study 80 children were randomly allocated into 2 groups receiving during first month of life HF (experimental group) or CMF (control group). At the age of 5-7 years, 62 children among 74 available (84%) with mean birthweight 1124g were evaluated according to standardized ISAAC (International Study of Asthma and Allergies in Childhood) protocol. Total IgE level, specific IgE, lymphocyte CD4+CCR4+/CD4+CXCR3+ ratio and skin prick tests (SPT) were done. Prevalence of obvious allergic diseases was not significantly different between the studied groups (HF: 12/33; CMF: 6/29; RR [relative risk] HF vs CMF: 1.76; 95%CI [confidence interval]: 0.76–4.09). Comparison of atopic status across groups revealed similar rate of positive markers of atopy: IgE (RR: 2.57 95%CI: 0.91–8,08), SPT (RR: 5.13; 95%CI: 0.93–31.6), lymphocyte CD4+CCR4+/CD4+CXCR3+ ratio (OR: 2.32; 95%CI: 0.78–7.53) in the both studied groups. Based on the carried out follow-up study we were unable to confirm the usefulness of hydrolyzed formula in prevention of allergy in an unselected cohort of very low birth weight infants.  相似文献   
992.
PURPOSE: The aim of the present study was to optimize and simplify photodynamic therapy using a new liposomal formulation of the photosensitizer meta-(tetrahydroxyphenyl)chlorin [m-THPC (Foscan); liposomal m-THPC (Fospeg)] and to reduce systemic reactions to the photosensitizer. EXPERIMENTAL DESIGN: To examine the pharmacokinetics of liposomal m-THPC, we determined tissue and plasma variables in feline patients with spontaneous squamous cell carcinoma. In vivo fluorescence intensity measurements of tumor and skin were done with a fiber spectrophotometer after i.v. injection of m-THPC or liposomal m-THPC in 10 cats. Blood samples, drawn at several time points after photosensitizer administration, were analyzed by high-performance liquid chromatography. RESULTS: None of the liposomal m-THPC-treated cats showed side effects during or after drug injection. Fluorescence intensities, fluorescence ratios (tumor fluorescence divided by skin fluorescence), and bioavailability in the tumor were 2 to 4 times higher with liposomal m-THPC compared with m-THPC. Liposomal m-THPC concentration in the tumor increased constantly to reach a maximum at 4 hours after injection. Plasma concentration and bioavailability were approximately 3 times higher with liposomal m-THPC compared with m-THPC measured at the time points of highest plasma concentration. The distribution half-life was shorter with liposomal m-THPC, resulting in maximal tumor accumulation up to 5.5 times earlier. Maximal tumor accumulation and maximal fluorescence ratio with liposomal m-THPC occurred at the same time point, indicating maximal selectivity. In both groups, all cats responded to therapy. CONCLUSIONS: Liposomal m-THPC was well tolerated by all cats and seems to have superior pharmacokinetic properties compared with m-THPC. The efficacy of the drug warrants further study.  相似文献   
993.
Objectives: (1) To compare a diagnostic yield of cardiac event recorders with that of 48‐hour Holler monitoring, (2) to determine the etiologies of palpitations, and (3) to assess an optimal duration of using an event recorder by a patient. Background: Palpitation is a common symptom which accounts for 16% of total complaints reported by patients in general medical settings. An ambulatory Holter ECG monitoring or an event recorder can be used to establish the cause of palpitations. Methods: (1)The study group consisted of 33 consecutive patients (24 females, 9 males, mean age 50 ± 32 years) with undiagnosed attacks of palpitations, occurring at least once per month. Each patient was randomly allocated to use either an event monitor or 48‐hour Holler monitoring. The patient kept the event monitor for 4 weeks. After the first monitor was returned, the patient was given the other device. Results: Holter monitoring determined the etiology of palpitations in 11 (33%) patients, and the event recorder in 21 (64%) patients (P = 0.0138). In the whole study group, the etiology of palpitations was disclosed in 23 (70%) patients. The diagnosis was possible using Holler ECG monitoring in only 2 (9%) patients, whereas the event recorder revealed the underlying mechanism of palpitations in 12 (52%) patients (P = 0.0007). In nine (39%) patients both methods were able to disclose the eliology of palpitations. The findings of 117 recordings obtained using an event recorder during palpitations were atrial fibrillation in 10 (9%), narrow QRS tachycardia in 4 (3%), frequent supraventricular eclopy in 17 (15%), frequent ventricular eclopy in 6 (5%), and episodes of palpitations sinus rhythm were recorded in the remaining 80 (68%). Of patients who experienced episodes of palpitations while using an event recorder, the earliest recording was obtained on the first day of the study, and the latest on the 18 day of using the event recorder. Conclusions: (1) The cardiac event recorders yield more diagnoses than 48‐hour Holter monitoring in patients with palpitations occurring at least once per month, (2) in this group of patients the event recorder provided a diagnostic ECG recording during the first 18 days of using the device, and (3) in the majority (57%) of patients a normal sinus rhythm was recorded during episodes of palpitations. A.N.E. 2000;5(4):315–321  相似文献   
994.
We evaluated C825T polymorphism of the G-protein beta3 subunit gene in syncopal patients in regard to tilting results and the diagnostic point score (PS). In a multivariate analysis, only PS > or = -2 was associated with positive passive tilting (P < 0.05). The relationship between tilting results and this polymorphism needs further study.  相似文献   
995.
BACKGROUND AND AIMS: Gender and age effect on brain morphology have been extensively investigated. However, the great variety in methods applied to morphology partly explain the conflicting results of linear patterns of tissue changes and lateral asymmetry in men and women. The aim of the present study was to assess the effect of age, gender and laterality on the volumes of gray matter (GM) and white matter (WM) in a large group of healthy adults by means of voxel-based morphometry. This technique, based on observer-independent algorithms, automatically segments the 3 types of tissue and computes the amount of tissue in each single voxel. METHODS: Subjects were 229 healthy subjects of 40 years of age or older, who underwent magnetic resonance (MR) for reasons other than cognitive impairment. MR images were reoriented following the AC-PC line and, after removing the voxels below the cerebellum, were processed by Statistical Parametric Mapping (SPM99). GM and WM volumes were normalized for intracranial volume. RESULTS: Women had more fractional GM and WM volumes than men. Age was negatively correlated with both fractional GM and WM, and a gender x age interaction effect was found for WM, men having greater WM loss with advancing age. Pairwise differences between left and right GM were negative (greater GM in right hemisphere) in men, and positive (greater GM in left hemisphere) in women (-0.56+/-4.2 vs 0.99+/-4.8; p=0.019). CONCLUSIONS: These results support side-specific accelerated WM loss in men, and may help our better understanding of changes in regional brain structures associated with pathological aging.  相似文献   
996.
Background: Clinical studies have explored the relationship between toothbrushing and development of gingival recession (GR), but relevant GR data for the multidirectional power toothbrush (PT) are lacking. The aim of this study is to evaluate the effect of brushing with either a multidirectional PT or American Dental Association reference manual toothbrush (MT) on mid‐buccal preexisting GR (PreGR) during 12 months. Methods: This was a 12‐month prospective, single‐masked, parallel‐group, randomized, controlled clinical study. Healthy participants without periodontitis with at least two teeth showing PreGR ≥2 mm were randomized to a group brushing with either an MT or PT. The primary outcome parameter was change at sites with PreGR ≥2 mm. All clinically based GR measurements were performed by one calibrated examiner at baseline, 6, and 12 months. Secondary outcomes were changes of GR at all mid‐buccal sites (with or without PreGR), changes in percentage of GR sites demonstrating a change of ≥1 mm, and changes in probing depths. Results: A total of 107 participants completed the study (PT: 55, MT: 52). During the 12‐month study period the mean recession at sites with PreGR ≥2 mm decreased significantly from 2.2 to 2.1 mm in both groups (P <0.05). The extent of GR parameters did not differ between MT and PT groups at any time point. GR evaluated clinically and on stone casts was well correlated. Conclusion: Neither the PT nor MT led to an increase in PreGR during 12 months of daily use.  相似文献   
997.

Objectives

The aim of this study was to assess the bonding properties between CAD/CAM resin and three resin composite cements combined with different bonding agents using three test methods.

Materials and methods

Four hundred twenty CAD/CAM resin substrates were fabricated and divided into three test methods (shear bond strength (SBS, n?=?180), tensile bond strength (TBS, n?=?180) and work of adhesion (WA, n?=?60)), further into four pretreatment methods (VP connect (VP), visio.link (VL), Clearfil Ceramic Primer (CP) and no pretreatment (CG)) and three cements (RelyX ARC, Variolink II and Clearfil SA Cement). Each subgroup contained 15 specimens. SBS and TBS were measured after 24 h H2O/37 °C?+?5000 thermal-cycles (5/55 °C) and failure types were assessed. WA was determined for pretreated CAD/CAM resin and non-polymerized resin composite cements. Data were analysed with Mann–Whitney U, Kruskal–Wallis H, Chi2 and Spearman’s Rho tests.

Results

Within SBS and TBS tests, CGs and groups pretreated with CP (regardless of resin composite cements), and VP pretreated with Clearfil SA Cement showed no bond. However, CG combined with RelyX ARC showed a TBS of 5.6?±?1.3 MPa. In general, highest bond strength was observed for groups treated with VL. CG and groups pretreated using VL showed lower WA than the groups treated with VP or CP.

Conclusions

Measured TBS values were higher than SBS ones. In general, SBS and TBS showed similar trends for the ranges of the values for the groups. WA results were not comparable with SBS/TBS results and admitted, therefore, no conclusions on it.

Clinical relevance

For a clinical use of XHIP-CAD/CAM resin, the bond surface should be additionally pretreated with visio.link as bonding agent.
  相似文献   
998.

Background

Cardiac troponins are often elevated in patients with skeletal muscle disease who have no evidence of cardiac disease.

Objectives

The goal of this study was to characterize cardiac troponin concentrations in patients with myopathies and derive insights regarding the source of elevated troponin T measurements.

Methods

Cardiac troponin T (cTnT) and cardiac troponin I (cTnI) concentrations were determined by using high sensitivity assays in 74 patients with hereditary and acquired skeletal myopathies. Patients underwent comprehensive cardiac evaluation, including 12-lead electrocardiogram, 24-h electrocardiogram, cardiac magnetic resonance imaging, and coronary artery computed tomography. cTnT and cTnI protein expression was determined in skeletal muscle samples of 9 patients and in control tissues derived from autopsy using antibodies that are used in commercial assays. Relevant Western blot bands were subjected to liquid chromatography tandem mass spectrometry for protein identification.

Results

Levels of cTnT (median: 24 ng/l; interquartile range: 11 to 54 ng/l) were elevated (>14 ng/l) in 68.9% of patients; cTnI was elevated (>26 ng/l) in 4.1% of patients. Serum cTnT levels significantly correlated with creatine kinase and myoglobin (r = 0.679 and 0.786, respectively; both p < 0.001). Based on cTnT serial testing, 30.1% would have fulfilled current rule-in criteria for myocardial infarction. Noncoronary cardiac disease was present in 23%. Using cTnT antibodies, positive bands were found in both diseased and healthy skeletal muscle at molecular weights approximately 5 kDa below cTnT. Liquid chromatography tandem mass spectrometry identified the presence of skeletal troponin T isoforms in these bands.

Conclusions

Measured cTnT concentrations were chronically elevated in the majority of patients with skeletal myopathies, whereas cTnI elevation was rare. Our data indicate that cross-reaction of the cTnT immunoassay with skeletal muscle troponin isoforms was the likely cause.  相似文献   
999.
Met provides essential signals for liver regeneration   总被引:24,自引:0,他引:24       下载免费PDF全文
Genetic analysis in mice has demonstrated a crucial role of the Met tyrosine kinase receptor and its ligand, hepatocyte growth factor/scatter factor (HGF/SF), in development of the liver, muscle, and placenta. Here, we use conditional mutagenesis in mice to analyze the function of Met during liver regeneration, using the Mx-cre transgene to introduce the mutation in the adult. After partial hepatectomy in mice carrying the Mx-cre-induced Met mutation, regeneration of the liver is impaired. Comparison of signal transduction pathways in control and mutant livers indicates that Met and other signaling receptors cooperate to fully activate particular signaling molecules, for instance, the protein kinase Akt. However, activation of the Erk1/2 kinase during liver regeneration depends exclusively on Met. Signaling crosstalk is thus an important aspect of the regulation of liver regeneration. Analysis of cell cycle progression of hepatocytes in conditional Met mutant mice indicates a defective exit from quiescence and diminished entry into S phase. Impaired liver regeneration is accompanied by compensatory physiological responses that include prolonged up-regulation of HGF/SF and IL-6 in peripheral blood. Our data demonstrate that the HGF/SF/Met signaling system is essential not only during liver development but also for the regeneration of the organ in the adult.  相似文献   
1000.
OBJECTIVE: Candida albicans frequently inhabits the gastrointestinal tract of humans leading to gastrointestinal candidiasis, especially following suppression of gastric acidity, but studies on the relation between this fungal infection and gastric pathology are limited due to lack of convenient animal models resembling Candida infection in humans. MATERIAL AND METHODS. We compared the effects of C. albicans and vehicle inoculation on gastric secretion and healing of gastric ulcers induced by acetic acid in rats treated with 1) ranitidine (30 mg kg(-1) day(-1) s.c.) and 2) aspirin (ASA) (60 mg kg(-1) day(-1) i.g.) with or without probiotic bacteria Lactobacillus acidophillus. At day 0 and at 4, 15 and 25 days after ulcer induction, the ulcer area, the gastric blood flow (GBF), the quantitative gastric cultures of Candida and the expression of mRNAs for pro-inflammatory cytokines IL-1beta and TNF-alpha and growth factors EGF and TGFalpha were assessed in the gastric mucosa. RESULTS: Gastric acid output was reduced by over 40% soon after Candida inoculation and this effect persisted during all time intervals tested. The area of ulcers in control rats significantly decreased at day 15 and the ulcers disappeared almost completely after 25 days of their induction. In contrast, the ulcers were present until day 25 in Candida-inoculated rats followed by a fall in GBF and a rise in plasma gastrin levels, these effects being significantly attenuated by the co-treatment with Lactobacillus. Candidiasis was accompanied by up-regulation of mRNA for IL-1beta, TNF-alpha, EGF and TGFalpha and a significant increment in plasma IL-1beta and TNF-alpha levels. CONCLUSIONS: 1) Persistent colonization with Candida could be achieved in rats treated with antisecretory agents or non-steroidal anti-inflammatory drugs (NSAIDs) such as ASA; 2) candidiasis reduces gastric acid secretion, while delaying ulcer healing possibly due to the impairment in GBF in the ulcer area and enhanced expression and release of IL-1beta and TNFalpha and 3) probiotic therapy could be useful in the treatment against the deleterious action of fungal infection on the healing of pre-existing gastric ulcers.  相似文献   
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