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OBJECTIVE: Vitiligo is a multifactorial polygenic disorder with a complex pathogenesis. It is related to both genetic and no genetic factors. The role of genetics is currently studied with several analytical approaches, such as genetic linkage, candidate gene association studies, genome-wide association studies (GWAS), deep DNA re-sequencing and gene expression studies. To date, there are no genetic traits directly related to vitiligo pathogenesis. PATIENTS AND METHODS: 43 cases of vitiligo patients and 30 healthy donors recruited as control, were screened by assaying the biochemical molecules involved in the self-cells cytotoxicity (haptoglobin and homocysteine) and candidate genes involved in the regulatory process of the re-methylation cycles and transsulfuration. Candidate genes and their polymorphisms screened are methylene-tetrahydrofolate-reductase (MTHFR) C677T and A1298C; cystathionine-beta-synthase enzyme (CBS) I278T and Ins68bp; and methionine-synthase-reductase (MTRR) A66G. RESULTS: A peculiar genetic profile in vitiligo patients are defined: 11.6% of vitiligo patients shown polymorphic variant MTHFR 677TT vs. 3.3% of healthy donor MTHFR 677CC profile (p=0.0017); 14.0% of vitiligo patients shown CBS polymorphic variant 278TT vs. 3.3% of healthy donor 278II profile (p=0.0012); and 11.6% of vitiligo patients shown MTRR 66GG vs. 3.3% of healthy donor MTRR 677AA profile (p>0.0001). CONCLUSIONS: This is the first study reporting the correlation between the polymorphic status of MTHFR C677T, CBS I278T, and MTRR A66G and vitiligo. The genetic screening of these polymorphisms could be useful for early detection of the inheritance risk factor in a subject carrying relatives with vitiligo. Although these data could suggest a kind of dysregulation, genetically based, of thiols production mechanisms. Based on these results, we have not been able to get hypothesis about the putative pathogenesis of vitiligo, and the precise cause remains unclear.

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Myocardial infarction is the leading cause of morbidity and mortality in developed countries. It causes a left ventricular dysfunction, mainly due to the loss of functional tissue, resulting in heart failure. New therapies are being developed, using a tissue engineering approach, with the ultimate goal of restoring cardiac function by regenerating and repairing the damaged myocardium. In the present study we investigated the behaviour of a specific population of c-kit positive human cardiac stem cells, called Multipotent Adult Stem Cells (MASCs), grown within three-dimensional collagen scaffolds (3D), to establish whether they could be used in post-infarction cardiac regeneration. We also evaluated the expression levels of the Granulocyte Macrophage-Colony Stimulating Factor Receptor (GM-CSFR) and endoglin, a component of the Transforming Growth Factor beta (TGF-ß) receptor complex. Finally, we also evaluated the expression of the α2ß1integrin. MASCs cultured within 3D collagen matrices are able to proliferate and migrate even in the absence of chemotactic agents and express high levels of factors involved in cell proliferation and migration, such as GM-CSFRα chain and integrins. They therefore represent a promising approach to tissue engineering aimed to restore cardiac function. Our results also suggest a role of GM-CSF in cell proliferation, while TGF-ß does not seem to be relevant.

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The sex steroid hormone 17ß-estradiol (E2) upregulates the levels of neuroglobin (NGB), a new neuroprotectant globin, to elicit its neuroprotective effect against H(2)O(2)-induced apoptosis. Several mechanisms could be proposed to justify the NGB involvement in E2 prevention of stress-induced apoptotic cell death. Here, we evaluate the ability of E2 to modulate the intracellular NGB localization and the NGB interaction with mitochondrial cytochrome c following the H(2)O(2)-induced toxicity. Present results demonstrate that NGB is expressed in the nuclei, mitochondria, and cytosol of human neuroblastoma SK-N-BE cells. E2, but not H(2)O(2) treatment of SK-N-BE cells, reallocates NGB mainly at the mitochondria and contemporarily reduces the number of apoptotic nuclei and the levels of cleaved caspase-3. Remarkably, the E2 treatment strongly increases NGB-cytochrome c association into mitochondria and reduces the levels of cytochrome c into the cytosol of SK-N-BE cells. Although both estrogen receptors (ERα and ERß) are expressed in the nucleus, mitochondria, and cytosol of SK-N-BE cells, this E2 effect specifically requires the mitochondrial ERß activity. As a whole, these data demonstrate that the interception of the intrinsic apoptotic pathway into mitochondria (i.e., the prevention of cytochrome c release) is one of the pivotal mechanisms underlying E2-dependent NGB neuroprotection against H(2)O(2) toxicity.

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Neuroglobin (Ngb), so named after its initial discovery in brain neurones, has received great attention as a result of its neuroprotective effects both in vitro and in vivo. Recently, we demonstrated that, in neurones, Ngb is a 17ß-oestradiol (E(2) ) inducible protein that is pivotal for hormone-induced anti-apoptotic effects against H(2) O(2) toxicity. The involvement of Ngb in other brain cell populations, as well as in other neuroprotective effects of E(2) , is completely unknown at present. We demonstrate Ngb immunoreactivity in reactive astrocytes located in the proximity of a penetrating cortical injury in vivo and the involvement of Ngb in the E(2) -mediated anti-inflammatory effect in primary cortical astrocytes. Upon binding to oestrogen receptor (ER)ß, E(2) enhances Ngb levels in a dose-dependent manner. Although with a lesser degree than E(2) , the pro-inflammatory stimulation with lipopolysaccharide (LPS) also induces the increase of Ngb protein levels via nuclear factor-(NF)κB signal(s). Moreover, a negative cross-talk between ER subtypes and NFκB signal(s) has been demonstrated. In particular, ERα-activated signals prevent the NFκB-mediated Ngb increase, whereas LPS impairs the ERß-induced up-regulation of Ngb. Therefore, the co-expression of both ERα and ERß is pivotal for mediating E(2) -induced Ngb expression in the presence of NFκB-activated signals. Interestingly, Ngb silencing prevents the effect of E(2) on the expression of inflammatory markers (i.e. interleukin 6 and interferon γ-inducible protein 10). Ngb can be regarded as a key mediator of the different protective effects of E(2) in the brain, including protection against oxidative stress and the control of inflammation, both of which are at the root of several neurodegenerative diseases.

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OBJECTIVE: To compare the chromosomal types of Mycobacterium avium strains infecting HIV-negative and AIDS patients in Greece. METHODS: In total, 41 Mycobacterium avium isolates, 23 from AIDS and 18 from HIV-negative patients, were compared by pulsed-field gel electrophoresis of genomic DNA after XbaI digestion. The majority (87%) of AIDS isolates were from disseminated infection, while the majority (61%) of HIV-negative isolates were from children with cervical lymphadenitis. RESULTS: Pulsed-field gel electrophoresis classified strains whose electrophoretic patterns were at least 85% similar into three clusters, A (four isolates), B (12 isolates), and C (15), while 10 isolates remained outside of these clusters. There was no statistically significant correlation of any PFGE cluster with a specific patient group. Within each patient group, no significant correlation of PFGE type with time, place of residence or, in the case of AIDS patients, hospital attended was observed. CONCLUSIONS: Genotypic similarities between isolates responsible for disseminated infection in AIDS patients and lymphadenitis in HIV-negative children suggest that related strains, possibly from an environmental source, cause both types of infections.

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Aim of the present study was to evaluate the effect of cefamandole, cefuroxime and cefoxitin on the level of gastrointestinal (GI) colonization by Candida albicans in humans. Twenty-eight adult patients received one of these three cephalosporins for 10 days, as treatment of infection, and were studied prospectively. Quantitative stool cultures for yeasts were performed immediately before, at the end, and 1 week after discontinuation of treatment. All three antibiotics caused an increase of the yeast concentration in the fecal flora. The increase caused by cefoxitin was the highest (2.5 log10 CFU/g of stool). Our results suggest that the cephalosporins tested cause minor increases of the colonization of the GI tract by C. albicans.

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Mycobacterium gordonae was isolated as a light growth from bronchoalveolar aspirates from nine patients over 12 months. All patients were in one hospital, and had been bronchoscoped for suspected malignancy. None of the patients had symptoms or radiographic findings of mycobacterial infection. The isolates were characterized by biochemical tests and molecular hybridization. Random amplified polymorphic DNA analysis (RAPD) was used to test whether the strains had a common origin. All the isolates generated four to eight fragments, and almost all presented distinct RAPD patterns. Antimicrobial resistance patterns to six agents confirmed that the isolates were unrelated. Thus epidemiologically unrelated strains of M. gordonae can exist as contaminants in the same department over a relatively short time frame. RAPD analysis is easy to perform, gives rapid results, and can be used for epidemiological analysis of M. gordonae isolates.

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There is a geographic distribution of Mycobacterium tuberculosis strains with various rpoB gene mutations that account for rifampin resistance. We studied 17 rifampin-resistant clinical isolates from patients in Greece to identify rpoB mutations. The aim of our study was the evaluation of a commercially available line probe assay kit (INNO-LiPA Rif. TB) to detect rpoB mutations and rifampin resistance. The results obtained with the commercially available assay were compared to those obtained by automated DNA sequence analysis of amplified PCR products. Randomly amplified polymorphic DNA (RAPD) analyses of the isolates were also performed. The overall concordance of the line probe assay with phenotypic rifampin susceptibility test was 94%. Three distinct rpoB mutations in codons Ser531, His526, and Asp516 were correctly identified with the kit, but mutations in external regions and insertions were detected only by automated DNA sequence analysis. The changes in codons Ser531 and His526 accounted for the majority of rifampin resistance, as previously described for isolates from other geographic areas. The results obtained by RAPD analyses of the isolates suggested that clonally related M. tuberculosis strains can have subclones bearing distinct mutant rpoB alleles. We conclude that this line probe assay kit, which is fast and with which tests are easy to perform, can be used for the rapid detection of rifampin resistance in M. tuberculosis before the availability of results by conventional methods and for epidemiological studies but that negative results obtained by this method do not rule out rifampin resistance.

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Forty human clinical Mycobacterium avium-M. intracellulare complex strains isolated in Greece were characterized to the species level by PCR with three sets of primers specific for one or both species. M. avium predominated in both human immunodeficiency virus-positive and -negative patients, but the frequency of M. intracellulare isolation appeared to be higher in the latter.

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The antibiotic susceptibilities of 1,002 Streptococcus pneumoniae clinical isolates from patients with community-acquired pneumonia were determined over an 18-month period. Resistance rates were 14% for penicillin, 20% for erythromycin, 26% for tetracycline, and 1% for chloramphenicol. Resistance to non-beta-lactam antibiotics was associated with penicillin resistance at statistically levels.

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Pentagastrin stimulated gastric secretion was measured in 12 healthy male subjects after repeated once daily oral administration of 20 and 40 mg BY 1023/SK&F 96022--a new substituted benzimidazole derivative. Twenty milligrams inhibited acid output compared with placebo by 24% (2.5-3.5 h) and 26% (24.5-25.5 h) after the first oral intake. Inhibition increased to 56% and 50%, respectively, after the seventh oral dose. Forty milligrams inhibited acid output by a mean of 51% (2.5 to 3.5 h) and 52% (24.5-25.5) after the first oral intake. After the seventh dose mean inhibition rose to 85% and 66%, respectively. The drug was well tolerated, no drug-related changes in clinical laboratory, ECG, heart rate and blood pressure were observed. Fasting gastrin serum concentrations tended to increase with both doses, the mean values being within the normal range. AUC, Cmax and t1/2 of the drug after repeated oral intake were not significantly different when compared with a single dose at either 20 mg or 40 mg.

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Acetylsalicylic acid (ASS) is increasingly used in the prevention of cardiovascular diseases. In recent years daily ASS-doses (100 to 300 mg) have been given for this indication. Studies with still lower ASS-doses (f. i. 30 mg daily) are the focus of ongoing clinical trials. In a randomized double-blind study we have evaluated the gastroduodenal tolerability of 30 mg ASS and 300 mg ASS daily in 20 healthy volunteers using upper GI-endoscopy. Both ASS-dosages have been taken for a period of four weeks. Endoscopic controls were performed at entry and repeated after seven, 14 and 28 days of treatment. 30 mg ASS daily did not induce significant gastroduodenal damages during the whole treatment period in contrast to 300 mg ASS daily (p less than 0.05). The lesions score under 300 mg ASS on day 7 and 28 was almost identical. Our data suggest that extremely low doses of ASS are almost harmless to the human gastroduodenal mucosa. No adaptive phenomena occur during a 28 days treatment with 300 mg ASS daily.

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DNOC, Ferbam and Imidan were tested in (C3H X C57BL/6) F1 mice to assess their potential testicular toxicity. Chemicals were administered i.p. and per os at different doses for 5 consecutive days. After 35 days the testicular was toxicity was evaluated by measuring the testicular weights, the sperm counts and the percentage of abnormal sperm. DNOC and Imidan failed to induce teratospermia in mice treated by both routes of administration. Conversely Ferbam induced a statistically significant increase in teratospermia only following per os administration to mice at a dose of 1000 mg/kg b.w./day. These data indicate that per os administration of Ferbam succeeded in producing active metabolites able to interfere with the differentiation process of spermatogenic cells.

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In a randomized double-blind study the gastroduodenal tolerability of 300 mg ASS daily has been evaluated in the presence of 150 mg ranitidine bid or placebo in 20 healthy volunteers using upper GI-endoscopy. The treatment period lasted 14 days. Endoscopic controls were performed at entry, and repeated at day 7 and day 14. At entry, the mean endoscopic score averaged 0.8 +/- 0.1 in the ASS/placebo-group and 1.0 +/- 0.0 in the ASS/ranitidine group. 300 mg ASS daily induced in the placebo experiments marked gastroduodenal alterations both at day 7 and day 14 (4.7 +/- 1.2 and 6.5 +/- 2.1, respectively). Concomitant administration of 150 mg ranitidine bid afforded almost full protection against 300 mg ASS daily both on day 7 and day 14 (1.9 +/- 0.6 and 2.1 +/- 0.8, respectively) (p less than 0.05). Our data suggest that coadministration of ranitidine 150 mg bid reduces almost completely gastroduodenal lesions evoked by acetylsalicylic acid 300 mg daily.

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339 patients with rheumatic diseases suffering from dyspepsia and endoscopically proven gastroduodenal lesion entered an open multicenter study with ranitidine 150 mg bid or ranitidine 300 mg administered at night in a single dose over 4 weeks. For entry the patients had to have been treated for at least 3 months with the non-steroidal anti-inflammatory drugs diclofenac, indomethacin and piroxicam. During the trial all patients were continued on NSAID. The data of 248 patients were evaluable. At entry, patients in both treatment groups had a total gastric damage score of 2.0. The duodenal lesion score was on average 1.43 in the ranitidine 150 mg bid group, and 1.8 in the 300 mg single dose ranitidine at night group. After 4 weeks of treatment the mean lesion score was significantly reduced in the stomach as well as in the duodenum with both ranitidine regimens, no differences being seen between the groups. In addition, rapid symptomatic relief was observed in both groups. After 4 weeks of treatment more than 80% of the patients were symptom-free or markedly improved.

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The protective action of an magnesium-aluminum-antacid (Mucal-Gel) against acute doses of acetylsalicylic acid (ASA) was studied in healthy subjects (n = 30) by a double-blind cross-over method. The severity of the lesion was determined by endoscopy. In the corresponding placebo experiments, severe lesions of the gastroduodenal mucosa were seen after administration of 1500 mg ASA. These lesions could be prevented only in the presence of high doses of the antacidum mixture. It is concluded from these studies that protective actions against ASA can be achieved only if the intragastric pH-level is adequately raised above 3.5 and higher.

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The gastroduodenal tolerability of tenoxicam vs diclofenac-Na was evaluated in a double-blind, parallel group study in 36 healthy male volunteers. The doses used were 20 mg tenoxicam vs 100 mg diclofenac-Na in a retard formulation daily over a period of 14 days. Gastric tolerability was assessed by using upper endoscopy. Gastroscopy was performed at base-line after the dosing period of 14 days and again after a follow-up period of 14 days without any treatment. The mucosal lesions were scored using modified Lanza criteria. In comparison to diclofenac-Na, tenoxicam was significantly better tolerated after a 14-day dosing period (mean gastric score: tenoxicam: 1.3 +/- 0.7; diclofenac-Na: 2.2 +/- 1.1 p = 0.0143). Both treatment groups had comparable scores at base-line and post-study assessments. Tenoxicam and diclofenac-Na were generally well tolerated. Only two volunteers reported intermittent lack of appetite, heartburn, and a feeling of pressure in the stomach. In summary, tenoxicam given as a 20 mg single oral morning dose over a 14-day period was significantly better tolerated than diclofenac 100 mg with regard to gastroduodenal mucosal damage.

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