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N Stavrianeas

Publications and source records attributed to N Stavrianeas.

15 recordsLinked to original sources
PubMed2006

Diabetes may increase risk for oral cancer through the insulin receptor substrate-1 and focal adhesion kinase pathway.

In light of recent epidemiological studies that associate diabetes mellitus with increased risk for oral cancer, we investigated in diabetic (type I) and normal rats with induced oral squamous cell carcinoma whether the molecular basis for that putative association involves insulin receptor substrate-1 (IRS-1) and focal adhesion kinase (FAK). Fourteen diabetic and 12 normal rats developed cancer after 4-nitroquinoline-N-oxide treatment, while six diabetic and six normal animals were used as controls. Oral sections were studied using monoclonal antibodies against IRS-1 and FAK proteins. Expression of IRS-1 was significantly higher in diabetic than normal rats, but it decreased in diabetic animals with tumor, especially in more advanced stages. FAK expression was significantly higher in rats with cancer in comparison to the ones without it, regardless the diabetes status. These data suggest that the IRS-1/FAK pathway is altered by diabetes resulting in reduced cell adhesion and possibly increasing risk for oral cancer.

Animals↗
PubMed2005

Prevalence of resistance-associated mutations in newly diagnosed HIV-1 patients in Greece.

The prevalence of HIV-1 drug resistance mutations in naïve patients has been previously shown to differ greatly with the geographic origin. The purpose of this study was to prospectively estimate the prevalence of HIV-1 drug resistance in Greece by analyzing a representative sample of newly HIV-1 diagnosed patients, as part of the SPREAD collaborative study. Protease (PR) and partial reverse transcriptase (RT) sequences were determined from 101 newly diagnosed HIV-1 patients, in Greece, during the period September 2002--August 2003, representing one-third of the total newly diagnosed HIV-1 patients in the same time period. The prevalence of HIV-1 drug resistance was estimated according to the IAS-USA mutation table taking into account all mutations in RT and only major mutations in PR region. The overall prevalence of resistance was 9% [95% confidence interval (CI): 4.2--16.2%]. The prevalence of mutations associated with resistance to NRTIs was 5% (95% CI: 1.6--11.2%), for NNRTIs was 4% (95% CI: 1.1--9.8%), while no major resistance mutations were found in PR. No multi-class resistance was detected in the study population. The prevalence of resistant mutations in the recent seroconverters was 22%. For two individuals, there was clear evidence for transmitted resistance based on epidemiological information for a known source of HIV-1 transmission. The prevalence of the HIV-1 non-B subtypes and recombinants was 52%.

Adult↗
PubMed2003

The relevance of peripheral blood T-helper 1 and 2 cytokine pattern in the evaluation of patients with mycosis fungoides and Sézary syndrome.

BACKGROUND: There is evidence that a T-helper (Th) 2 cytokine pattern dominates in the peripheral blood as well as in tissue of patients with Sézary syndrome (SS), and that the malignant clone is of Th2 phenotype. However, there are conflicting studies on the cytokine pattern in the peripheral blood in different stages of cutaneous T-cell lymphoma (CTCL). OBJECTIVES: To examine, by means of flow cytometry (FC), the Th1/Th2 cytokine profile [cytoplasmic interferon (IFN)-gamma/interleukin (IL)-4] in peripheral blood T cells from patients with mycosis fungoides (MF) and SS, the most common forms of CTCL, and to correlate their expression with clinical stage, clonality and T-cell immunophenotype changes in order to evaluate their relevance in CTCL progression. METHODS: We investigated by FC the percentage of CD3+ T cells expressing cytoplasmic IFN-gamma and IL-4 after stimulation in blood specimens of 43 CTCL patients (32 stage I-II and 11 stage III-IV), eight of whom were erythrodermic. Next, we compared cytoplasmic IFN-gamma and IL-4 expression between patients of different stages and controls, and correlated our findings to T-cell receptor (TCR)-gamma gene rearrangement, used as a marker of clonality, and changes in T-cell immunophenotype (CD4+, CD8+, CD4+/CD7-, CD4+/CD25+) and natural killer cells. Polymerase chain reaction amplification of the TCR-gamma gene was performed in 41 blood and 26 skin specimens. We also examined the cytokine expression pattern in patients with erythrodermic MF and SS. RESULTS: A significantly higher frequency of CD3+/IL-4+ T cells was found in late (III-IV) compared with early (I-II) CTCL patients (P = 0.002) or controls (P < 0.001). There were significant positive correlations between the percentages of CD3+/IL-4+ and the percentages of CD3+/CD4+ T cells (r = 0.385, P = 0.05), CD4+/CD7- T cells (r = 0.335, P < 0.05) and CD4+/CD25+ T cells (r = 0.433, P = 0.01); there was a negative correlation between the percentages of CD3+/IL-4+ and CD3+/CD8+ T cells (r = -0.463, P = 0.005) and a positive correlation between the percentages of CD3+/IFN-gamma+ and CD3+/CD8+ T cells (r = 0.368, P = 0.02). Increased percentages of CD3+/IL-4+, CD3+/CD4+ and CD4+/CD7- T lymphocytes were associated with the presence of clonality (P = 0.025, P < 0.001 and P = 0.0031, respectively). All independent variables showed a statistically significant difference between SS and erythrodermic MF patients, or controls, apart from cytoplasmic IL-4, which was high both in erythrodermic MF and SS patients compared with controls (P = 0.003 and P = 0.008, respectively). In multiple regression logistic analysis, the probability of belonging to advanced CTCL stages was associated only with increased cytoplasmic IL-4 (P = 0.007, odds ratio 1.13, 95% confidence interval 1.033-1.229). CONCLUSIONS: Increased T-cell cytoplasmic IL-4 is more frequent in late CTCL stages, correlates with T-cell immunophenotype changes found in advanced disease and is associated with clonality. Increased cytoplasmic IL-4 is frequent both in erythrodermic MF and SS patients, in contrast to other variables found increased only in SS, suggesting that IL-4 may be an early indicator of disease progression. Moreover, our results show that increased cytoplasmic IL-4 is the sole predictor of advanced CTCL disease and confirm the relevance of FC determination of IL-4 in the routine evaluation of CTCL cases.

Adult↗
PubMed1999

The effect of proteolytic enzymes on hair follicles of transgenic mice expressing the lac Z-protein in cells of the bulge region.

OBJECTIVE: To study the effects of proteolytic enzymes on mice hair follicles, particularly on cells of the bulge area regarded as follicle stem cells. BACKGROUND: Previous application by iontophoresis of proteolytic enzymes on guinea pig skin resulted in degenerative effects on hair follicles and the hypothesis was proposed that some of the affected cells could be stem cells. METHODS: To mark putative stem cells transgenic mice were produced carrying the lac-Z gene fused to the Upstream Regulatory Region (URR) of Human Papilloma Virus 11 (HPV11), as they express this gene specifically in the cells of the bulge area. Chymotrypsin and papain were applied on skin by iontophoresis, trypsin in the form of liposomes. RESULTS: Enzyme application, both by electrophoresis and as liposomes, led to intense degenerative effects of the hair follicle, such as detachment of the inner root sheath, cystic dilation of the hair shaft and presence of epithelial cells within the lumen. Some of these cells represent hair follicle stem cells expressing beta-galactosidase (beta-gal), having been detached from the bulge area as a result of enzyme treatment, implying impairment of their function.

Animals↗
PubMed1998

Classic Kaposi's sarcoma in two young heterosexual men.

Classic Kaposi's sarcoma is primarily a skin disease of the lower extremities affecting predominantly elderly men of Mediterranean origin. We report classic Kaposi's sarcoma first presenting in the third decade in two heterosexual, HIV-negative, males of Greek origin from Albania. Ten years after onset, the disease became aggressive with unusual clinical features that included exophytic tumors, extensive lesions on the hands as well as the legs, and prominent leg edema. One of the patients also presented lesions on the face, trunk and palate, and bubonic lymphadenopathy. In both cases, CD4 counts were normal and HLA-DR5 was positive. Treatment included radiation therapy, subcutaneous interferon (alpha-2b) and combined chemotherapy (ABV). At follow up 1 and 2 years later, both patients remain in partial remission with significant improvement in clinical disease, on maintenance interferon.

Adult↗
PubMed1997

[Cutaneous hyalinosis: 3 cases].

INTRODUCTION: The authors report three cases of "Hyalinosis cutis et mucosae"; the first and the second case concern two siblings children (brother and sister) while the third is reported on a 42-year-old woman. PRESENTATION OF CASES: The case history and the personal anamnesis, the morphology of the skin lesions, the symptoms indicating laryngeal mucous affection as well as the histopathological picture, are compatible with the "Urbach-Wiethe disease". Furthermore, in the third case, the electron microscopic findings confirm the diagnosis. DISCUSSION: The particularities of the present cases are discussed in connection with the corresponding bibliographical data.

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PubMed1984

Leishmaniasis in Greece II. Isolation and identification of the parasite causing cutaneous leishmaniasis in man.

The serological and biochemical identity of four Greek leishmanial strains isolated from cases of cutaneous leishmaniasis was determined. All four strains were identical and shown to be Leishmania tropica (formerly L. t. minor). The cases are described; two came from the Greek mainland and two from Greek islands, one of the latter being a case of leishmaniasis recidivans. The significance of the results is discussed, in particular the co-existence in Greece of strains of L. tropica and L. donovani infantum.

Adult↗
PubMedDate not supplied

Virological and immunological response to HAART therapy in a community-based cohort of HIV-1-positive individuals.

PURPOSE: To determine virological and immunological response to highly active antiretroviral therapy (HAART) and to investigate factors influencing response in a community-based setting. METHOD: Plasma HIV RNA levels and CD4 cell counts were studied in 168 unselected individuals starting HAART including indinavir or ritonavir or hard-gel saquinavir-containing regimens. RESULTS: Overall, 60% of the patients reduced their HIV RNA to below 500 Eq/mL, but half of them experienced a subsequent virologic rebound. Patients with higher baseline HIV RNA, higher baseline CD4 cell count, and simultaneous initiation of combination therapy and patients on indinavir or ritonavir regimen were more likely to have virologic response within 6 months since HAART initiation. Patients with lower baseline CD4 cell count and with lower rates of viral clearance had a higher probability of a subsequent virologic rebound. Forty percent of the patients had increased their CD4 cell counts by more than 100 cells/microL (immunologic response). The probability of immunologic response was independent of baseline HIV RNA levels and CD4 cell count; however, the more complete the virologic suppression, the higher the probability of immunologic response. Thirty percent of the patients had discordance between virologic and immunologic responses. CONCLUSION: The rate of virologic failure in this unselected group of patients was higher than that observed in randomized clinical trials, but only a minority (11%) of the patients were treatment naïve. Starting combination therapy simultaneously and initiating antiretroviral therapy before advanced HIV disease has developed predict virologic response, whereas the magnitude of viral suppression predicts mid to long immunological response.

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