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For the past 10 years the alfa-hydroxyacids and the bovine collagen injection have been used for peeling and the correction of multiple skin diseases. Until now, such progressive achievement has occurred in separate parallels just like the indications that have been held distinct. However, the studies carried out in order to clarify the mechanical action of the two substances have shown a common and fundamental denominator: the stimulation of synthesis of the new collagen in the patient's skin. On the basis of these results and the existence of common clinical indications of the use of glycolic acid and collagen, the authors have worked out a protocol involving a combined and contemporary application in progressive steps. They developed the rationales of such protocol and analyzed the results of its application on a number of carefully selected patients for a clinical comparison and on a sample of rats for a histological comparison. They have concluded that the contemporary use of glycolic acid and bovine collagen is a simple and safe method whose synergy action leads to more intense and long-lasting effects than the ones observed in the isolated application of the two substances. The authors have also obtained interesting and significant histological results.  相似文献   
3.
Results of a recent study have demonstrated that exposure to multiple ethanol concentrations and repeated ethanol deprivation periods in Indiana ethanol-preferring (P) rats resulted in the development of an alcohol deprivation effect (ADE; the temporary increase in voluntary ethanol intake after a period of deprivation from ethanol) characterized by consumption of intoxicating amounts of ethanol. The current study was designed to possibly extend these results to Sardinian alcohol-preferring (sP) rats, generated with the same selective program previously used for P rats. To this aim, ethanol-naive sP rats were exposed initially to the home cage four-bottle choice [10%, 20%, and 30% (vol./vol.) ethanol solutions and water] for eight consecutive weeks. Subsequently, rats were divided into two groups: The first group had continuous access to the four-bottle regimen (nondeprived rats), and the second group was exposed to five cycles of 14-day periods of deprivation from ethanol and 14-day periods of reexposure to the four-bottle regimen. An ADE developed after each deprivation period. However, the extra intake of ethanol was limited to the first hour of each reaccess period. Magnitude of ADE did not change with repeated periods of deprivation. However, a shift in preference toward the two highest concentrations of ethanol solutions was evident from the first reexposure to ethanol and was maintained throughout the study. These results provide further evidence on the heterogeneity of ethanol-drinking behavior among rat lines selectively bred for high ethanol preference and consumption.  相似文献   
4.
Proper management of Helicobacter pylori infection in clinical practice--when supported by evidence-based data--is expected to produce substantial cost-efficacy advantages. This consideration has prompted the Cervia Working Group to organise a meeting of experts to update the National Guidelines on the diagnosis and treatment of H. pylori infection in Italy. Recommendations in the new European Guidelines were considered in the National setting, here in the light of factors such as the incidence of gastric cancer and gastric lymphoma, the accessibility to different diagnostic tools, the prevalence of bacterial resistance against antibiotics, and the availability of different drugs. The main revisions in respect to the previous guidelines include H. pylori eradication in non-ulcer dyspepsia patients and in non-steroidal, anti-inflammatory drug users, as well as in patients with idiopathic thrombocytopenic purpura and iron deficiency anaemia. The stool antigen test is now accepted as a valid test for confirmation of H. pylori eradication following therapy. New therapeutic approaches have been recommended for both first- (sequential therapy) and second-line (levofloxacin-based) treatment in our country.  相似文献   
5.
Idebenone (45 mg twice daily) was administered to 7 patients with moderate renal impairment (creatinine clearance 21-40 ml/min) for 10 days. Standard pharmacokinetic parameters were computed on day 1 (single administration) and on day 10. On day 1 the mean of the maximum plasma concentration values (C(max)) was 364 ng/ml (standard deviation (S.D.) 100); time to C(max) (t(max)) was in the range of 1-2 h for 6 patients and 12 h for the remaining patient: the mean was 3 h (S.D. 3.99); the mean area under the plasma concentration vs. time curve (AUC) was 3005 ng h/ml (S.D. 1152). On day 10 the mean C(max) was 531 ng/ml (S.D. 355.3), the mean t(max) was 0.07 h (S.D. 0.19), the mean AUC was 3167 ng/ml (S.D. 2944) and the mean elimination half-life (t(1/2)) was 4.9 h (S.D. 1.1). Idebenone metabolites (QS-4, QS-6 and QS-10) showed a kinetic profile similar to the parent compound, with pharmacokinetic parameters comparable to idebenone for QS-4 and lower than idebenone for QS-6 and QS-10. Idebenone was metabolized and easily excreted and no accumulation was observed for the compound and its metabolites. No significant modification of the biohumoral indexes and vital signs and no adverse reactions were observed.  相似文献   
6.
The characterization of Mycobacterium tuberculosis antigens inducing CD4(+) T-cell responses could critically contribute to the development of subunit vaccines for M. tuberculosis. Here we performed computational analysis by using T-cell epitope prediction software (known as TEPITOPE) to predict promiscuous HLA-DR ligands in the products of the mce genes of M. tuberculosis. The analysis of the proliferative responses of CD4(+) T cells from patients with pulmonary tuberculosis to selected peptides displaying promiscuous binding to HLA-DR in vitro led us to the identification of a peptide that induced proliferation of CD4(+) cells from 50% of the tested subjects. This study demonstrates that a systematic computational approach can be used to identify T-cell epitopes in proteins expressed by an intracellular pathogen.  相似文献   
7.
Diabetic neuropathy affects both sensory and autonomic peripheral nerve fibres. Vasoactive intestinal polypeptide (VIP) is present in autonomic fibres which modulate sweat secretion, while calcitonin gene-related peptide (CGRP) is localized to cutaneous sensory fibres. In this study, immunohistochemistry and image analysis were used to assess changes of VIP and CGRP, and of the pan-neuronal marker protein gene-product (PGP)-9.5, in skin biopsies of 18 patients affected by type 1 diabetes (age range 18–46 years) and from seven aged-matched controls. Patients were divided into three groups: group 1 (n=6), with diabetes for 6 months to 3 years; group 2 (n=5), with the disease for 5–10 years; and group 3 (n=7), with diabetes for more than 10 years. VIP immunoreactivity (IR) and PGP-9.5-IR were significantly reduced around sweat glands (P <0.005) in groups 2 and 3. Epidermal CGRP-IR and PGP-9.5-IR were significantly reduced in group 3 (P <0.05). Twenty-eight per cent (5/18) of all patients showed high VIP-IR around sweat glands (>95 per cent confidence limits of controls) and all of these patients had diabetes for less than 3 years. Conversely, 55 per cent (10/18) of patients had low VIP-IR (<5 per cent confidence limit of controls). The latter, compared with the former, showed a significantly longer duration of diabetes (Fisher exact test P=0·002), presence of clinical autonomic neuropathy (Fisher exact test P=0.04), and a reduced sural nerve conduction velocity (Fisher exact test P=0.04). These results suggest that quantitative immunohistochemical analysis of peptide-containing cutaneous nerves allows an objective evaluation of nerve fibre alterations at early stages of diabetes than is currently possible with neurophysiological functional tests.  相似文献   
8.
We recently set up a gamma interferon (IFN-γ) enzyme-linked immunospot assay (ELISPOT), using selected early secreted antigenic target 6 (ESAT-6) peptides, that appears specific for active tuberculosis (A-TB). However, ELISPOT is difficult to automate. Thus, the objective of this study was to determine if the same selected peptides may be used in a technique more suitable for routine work in clinical laboratories, such as whole-blood enzyme-linked immunosorbent assay (WBE). For this purpose, 27 patients with A-TB and 41 control patients were enrolled. Our WBE, using the already described selected peptides from ESAT-6 plus three new ones from culture filtrate protein 10, was performed, and data were compared with those obtained by ELISPOT. Using our selected peptides, IFN-γ production, evaluated by both WBE and ELISPOT, was significantly higher in patients with A-TB than in controls (P < 0.0001). Statistical analysis showed a good correlation between the results obtained by WBE and ELISPOT (r = 0.80, P < 0.001). To substantiate our data, we compared our WBE results with those obtained by QuantiFERON-TB Gold, a whole-blood assay based on region of difference 1 (RD1) overlapping peptides approved for TB infection diagnosis. We observed a slightly higher sensitivity with QuantiFERON-TB Gold than with our WBE (89% versus 81%); however, our test provided a better specificity result (90% versus 68%). In conclusion, results obtained by WBE based on selected RD1 peptides significantly correlate with those generated by ELISPOT. Moreover, our assay appears more specific for A-TB diagnosis than QuantiFERON-TB Gold, and thus it may represent a complementary tool for A-TB diagnosis for routine use in clinical laboratories.  相似文献   
9.
We report on a 2-year-old girl with a de novo mutation [45,XX,der(5),t(5;14) (pter;q11.2)] with corpus callosum agenesis, multiple cysts (cerebral and cardiac), subtle eye abnormalities, and at least two different skin defects, strongly indicating neuroectodermal involvement, as a neuromuscular choristoma (hamartoma) and an eccrine hamartoma. Fluorescent in situ hybridization with different single-locus probes showed that chromosome 5 has a very small deletion, confined to a region composed of repetitive sequences. By contrast, the long (q) arm of chromosome 14 seems to be much more involved in the rearrangement, with partial monosomy spanning from the centromere to the D14S72 and D14S261 loci. The extent of the deleted region of chromosome 14 is approximately 16 cM. To our knowledge, this is the smallest reported deletion involving the chromosome 14q11.2 region to be associated with a developmental disorder resulting in variable eye, skin, and brain anomalies. We suggest that a new syndrome, mimicking in some ways the MLS phenotype, is caused by a deletion in the chromosome 14q11.2 region.  相似文献   
10.
Tissue inhibitor of metalloproteinases 1 (TIMP-1) inhibits several proteinases including a disintegrin and metalloproteinase 10 (ADAM10), a major alpha-secretase that cleaves the beta-amyloid precursor protein within its amyloidogenic Abeta domain. The gene encoding TIMP-1 (TIMP 1) maps to the short arm of the X chromosome, in a region previously suggested as conferring genetic susceptibility for Alzheimer's disease (AD). To determine whether genetic variability of TIMP 1 contributes to the pathogenesis of AD, we analysed one single nucleotide polymorphism within TIMP 1 and one single nucleotide polymorphism in the 5'-untranslated region of TIMP 1 in patients with AD and control subjects from two independent and ethnically different populations. We did not observe any association between TIMP 1 genotypes and the diagnosis of AD in men or women. We also measured TIMP-1 protein levels in the cerebrospinal fluid of patients with AD, healthy control subjects, and patients with other neurological disorders. TIMP-1 levels were similar in all groups. In addition, no significant differences were observed after stratification for TIMP 1 genotypes. Our data show that neither genetic variability nor protein levels of TIMP-1 are associated with AD.  相似文献   
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