Stellar archeology: a cosmological view of dwarf galaxies

The origin of dwarf spheroidal galaxies (dSphs) is investigated in a global cosmological context by simultaneously following the evolution of the Milky Way Galaxy and its dwarf satellites. This approach enable to study the formation of dSphs in their proper birth environment and to reconstruct their own merging histories. The proposed picture simultaneously accounts for several dSph and Milky Way properties, including the Metallicity Distribution Functions of metal-poor stars. The observed features are interpreted in terms of physical processes acting at high redshifts.Comment: 8 pages, 5 figures; "Dwarf Galaxies: Keys to Galaxy Formation and Evolution" JENAM 2010 Symposium S

POLAR registry (Promus eluting stent registry in Latin America ):1 year follow-up results

BACKGROUND: Drug-eluting stents have been used since 2002 in different patient populations aiming to achieve high success rates with low clinical and angiographic restenosis rates. With the late thrombosis adverse events associated to the first generation sirolimus and paclitaxel-eluting stents, second-generation everolimus and zotarolimus-eluting stents has been recently developed. METHODS: The POLAR registry is a prospective, non-randomized, multicenter study, which included 988 patients, totaling 1,362 lesions treated with the everolimus-eluting stent Promus®. In order to represent the clinical practice, almost all subtypes of patients and lesions were included in this registry. Clinical follow-up was planned to be performed 1, 6, 12 and 24 months after the procedure. RESULTS: Most patients were male (69.8%), with mean age of 64.9 ± 9.4 years, 35.2% were diabetics and 55% had been treated for acute coronary syndrome. Vessel diameter was 2.95 ± 0.43 mm and lesion extension was 20.5 ± 5.6 mm. A total of 1.14 ± 0.38 stent/patient were implanted and the procedural success rate was 96.6%. Major adverse cardiac events occurred in 4.5% of patients, and stent thrombosis was observed in 5 patients (0.5%) after a clinical follow-up of 12 months. CONCLUSIONS: The present registry suggests that everolimus-eluting stents are safe and effective in daily clinical practice patients, with a low rate of major adverse cardiac events at the end of the first year of follow-up.INTRODUÇÃO: Desde 2002, os stents farmacológicos são utilizados em diversas populações de pacientes objetivando alcançar elevados índices de sucesso, com baixas taxas de reestenose angiográfica e clínica. Com os resultados adversos em relação à trombose tardia associados aos stents farmacológicos de primeira geração eluidores de sirolimus e paclitaxel, surgiram recentemente os stents farmacológicos de segunda geração eluidores de zotarolimus e everolimus. MÉTODOS: O registro POLAR é um registro prospectivo, não-randomizado, multicêntrico, que incluiu 988 pacientes totalizando 1.362 lesões tratadas com o stent Promus®. Objetivando representar a prática clínica, praticamente todos os subtipos de pacientes e lesões foram incluídos neste registro. O seguimento clínico foi planejado para ser realizado 1 mês, 6 meses, 12 meses e 24 meses após o procedimento. RESULTADOS: A maioria dos pacientes era do sexo masculino (69,8%), com média de idade de 64,9 ± 9,4 anos, 35,2% eram diabéticos e 55% tinham sido tratados na vigência de síndrome coronária aguda. O diâmetro do vaso foi de 2,95 ± 0,43 mm e a extensão da lesão, de 20,5 ± 5,6 mm. Foi implantado 1,14 ± 0,38 stent/paciente e o sucesso do procedimento foi alcançado em 96,6% dos casos. Eventos cardíacos adversos maiores ocorreram em 4,1% dos pacientes, e trombose de stent esteve presente em 5 pacientes (0,5%) após o seguimento clínico de 12 meses. CONCLUSÕES: O presente registro sugere que os stents farmacológicos eluidores de everolimus são seguros e eficazes em pacientes da prática clínica diária, com baixas taxas de eventos cardíacos adversos maiores ao término do primeiro ano de seguimento.Universidade Federal de São Paulo (UNIFESP)Instituto Dante Pazzanese de CardiologiaStatus CorHospital Israelita Albert EinsteinENCORE Hospital Lúcio RebeloReal e Benemérita Associação Portuguesa de BeneficênciaHospital Cardiológico CostantiniHemodinâmica Meridional Intercath MeridionalInstituto de Cardiologia do Espírito SantoFundação Universitária de Cardiologia Instituto de Cardiologia do Rio Grande do SulUNIFESPSciEL

Cytogenetical studies in five Atlantic Anguilliformes fishes

The order Anguilliformes comprises 15 families, 141 genera and 791 fish species. Eight families had at least one karyotyped species, with a prevalence of 2n = 38 chromosomes and high fundamental numbers (FN). The only exception to this pattern is the family Muraenidae, in which the eight species analyzed presented 2n = 42 chromosomes. Despite of the large number of Anguilliformes species, karyotypic reports are available for only a few representatives. In the present work, a species of Ophichthidae, Myrichthys ocellatus (2n = 38; 8m+14sm+10st+6a; FN = 70) and four species of Muraenidae, Enchelycore nigricans (2n = 42; 6m+8sm+12st+16a; FN = 68), Gymnothorax miliaris (2n = 42; 14m+18sm+10st; FN = 84), G. vicinus (2n = 42; 8m+6sm+28a; FN = 56) and Muraena pavonina (2n = 42; 6m+4sm+32a; FN = 52), collected along the Northeastern coast of Brazil and around the St Peter and St Paul Archipelago were analyzed. Typical large metacentric chromosomes were observed in all species. Conspicuous polymorphic heterochromatic regions were observed at the centromeres of most chromosomes and at single ribosomal sites. The data obtained for Ophichthidae corroborate the hypothesis of a karyotypic diversification mainly due to pericentric inversions and Robertsonian rearrangements, while the identification of constant chromosome numbers in Muraenidae (2n = 42) suggests a karyotype diversification through pericentric inversions and heterochromatin processes

Multicentric phase II trial of gemcitabine plus epirubicin plus paclitaxel as first-line chemotherapy in metastatic breast cancer

In this phase II, multicentre trial, patients with metastatic breast cancer (MBC) were treated with a combination of gemcitabine, epirubicin and paclitaxel (GET). The primary objective of this study was to determine the tolerability and activity in terms of complete responce (CR) and overall response rate of the GET combination in this patient population. Patients with no prior treatment for MBC, and at least one bidimensionally measurable lesion received gemcitabine 1000 mg m(-2) intravenously (i.v.) over 30 min on days 1 and 4, followed by epirubicin i.v. at 90 mg m(-2) on day 1, and paclitaxel 175 mg m(-2) over 3 h on day 1, every 21 days, up to eight courses. From May 1999 to June 2000, 48 patients were enrolled from seven Italian institutions. A total of 297 chemotherapy courses were administered with a median of six cycles patient(-1) (range 1-8). Seven patients (15%) obtained CR and 27 patients (56%) had partial responce, for an overall response rate of 71% (95%; CI: 58.3-83.7). After a median follow-up of 23.7 months (range 7.0-34.4), median progression-free survival was 10.5 months (95%; CI: 9.2-11.7), and median overall survival 25.9 months. The main haematological toxicity consisted of grade 3 or 4 neutropenia that occurred in 62% of cycles (22% grade 4 and 40% grade 3). The GET combination is active and well tolerated as first-line chemotherapy for MBC

Giant breast tumors: Surgical management of phyllodes tumors, potential for reconstructive surgery and a review of literature

<p>Abstract</p> <p>Background</p> <p>Phyllodes tumors are biphasic fibroepithelial neoplasms of the breast. While the surgical management of these relatively uncommon tumors has been addressed in the literature, few reports have commented on the surgical approach to tumors greater than ten centimeters in diameter – the giant phyllodes tumor.</p> <p>Case presentation</p> <p>We report two cases of giant breast tumors and discuss the techniques utilized for pre-operative diagnosis, tumor removal, and breast reconstruction. A review of the literature on the surgical management of phyllodes tumors was performed.</p> <p>Conclusion</p> <p>Management of the giant phyllodes tumor presents the surgeon with unique challenges. The majority of these tumors can be managed by simple mastectomy. Axillary lymph node metastasis is rare, and dissection should be limited to patients with pathologic evidence of tumor in the lymph nodes.</p

DNA methylation patterns in bladder cancer and washing cell sediments: a perspective for tumor recurrence detection

<p>Abstract</p> <p>Background</p> <p>Epigenetic alterations are a hallmark of human cancer. In this study, we aimed to investigate whether aberrant DNA methylation of cancer-associated genes is related to urinary bladder cancer recurrence.</p> <p>Methods</p> <p>A set of 4 genes, including <it>CDH1 </it>(E-cadherin), <it>SFN </it>(stratifin), <it>RARB </it>(retinoic acid receptor, beta) and <it>RASSF1A </it>(Ras association (RalGDS/AF-6) domain family 1), had their methylation patterns evaluated by MSP (Methylation-Specific Polymerase Chain Reaction) analysis in 49 fresh urinary bladder carcinoma tissues (including 14 cases paired with adjacent normal bladder epithelium, 3 squamous cell carcinomas and 2 adenocarcinomas) and 24 cell sediment samples from bladder washings of patients classified as cancer-free by cytological analysis (control group). A third set of samples included 39 archived tumor fragments and 23 matched washouts from 20 urinary bladder cancer patients in post-surgical monitoring. After genomic DNA isolation and sodium bisulfite modification, methylation patterns were determined and correlated with standard clinic-histopathological parameters.</p> <p>Results</p> <p><it>CDH1 </it>and <it>SFN </it>genes were methylated at high frequencies in bladder cancer as well as in paired normal adjacent tissue and exfoliated cells from cancer-free patients. Although no statistically significant differences were found between <it>RARB </it>and <it>RASSF1A </it>methylation and the clinical and histopathological parameters in bladder cancer, a sensitivity of 95% and a specificity of 71% were observed for <it>RARB </it>methylation (Fisher's Exact test (p < 0.0001; OR = 48.89) and, 58% and 17% (p < 0.05; OR = 0.29) for <it>RASSF1A </it>gene, respectively, in relation to the control group.</p> <p>Conclusion</p> <p>Indistinct DNA hypermethylation of <it>CDH1 </it>and <it>SFN </it>genes between tumoral and normal urinary bladder samples suggests that these epigenetic features are not suitable biomarkers for urinary bladder cancer. However, <it>RARB </it>and <it>RASSF1A </it>gene methylation appears to be an initial event in urinary bladder carcinogenesis and should be considered as defining a panel of differentially methylated genes in this neoplasia in order to maximize the diagnostic coverage of epigenetic markers, especially in studies aiming at early recurrence detection.</p

Type II Heat-Labile Enterotoxins from 50 Diverse Escherichia coli Isolates Belong Almost Exclusively to the LT-IIc Family and May Be Prophage Encoded

Some enterotoxigenic Escherichia coli (ETEC) produce a type II heat-labile enterotoxin (LT-II) that activates adenylate cyclase in susceptible cells but is not neutralized by antisera against cholera toxin or type I heat-labile enterotoxin (LT-I). LT-I variants encoded by plasmids in ETEC from humans and pigs have amino acid sequences that are ≥95% identical. In contrast, LT-II toxins are chromosomally encoded and are much more diverse. Early studies characterized LT-IIa and LT-IIb variants, but a novel LT-IIc was reported recently. Here we characterized the LT-II encoding loci from 48 additional ETEC isolates. Two encoded LT-IIa, none encoded LT-IIb, and 46 encoded highly related variants of LT-IIc. Phylogenetic analysis indicated that the predicted LT-IIc toxins encoded by these loci could be assigned to 6 subgroups. The loci corresponding to individual toxins within each subgroup had DNA sequences that were more than 99% identical. The LT-IIc subgroups appear to have arisen by multiple recombinational events between progenitor loci encoding LT-IIc1- and LT-IIc3-like variants. All loci from representative isolates encoding the LT-IIa, LT-IIb, and each subgroup of LT-IIc enterotoxins are preceded by highly-related genes that are between 80 and 93% identical to predicted phage lysozyme genes. DNA sequences immediately following the B genes differ considerably between toxin subgroups, but all are most closely related to genomic sequences found in predicted prophages. Together these data suggest that the LT-II loci are inserted into lambdoid type prophages that may or may not be infectious. These findings raise the possibility that production of LT-II enterotoxins by ETEC may be determined by phage conversion and may be activated by induction of prophage, in a manner similar to control of production of Shiga-like toxins by converting phages in isolates of enterohemmorhagic E. coli

Androgen receptor expression in male breast carcinoma: lack of clinicopathological association

Androgen receptor (AR) expression was retrospectively analysed in 47 primary male breast carcinomas (MBCs) using a monoclonal antibody on formalin-fixed, paraffin-embedded tissues. AR immunopositivity was detected in 16 out of 47 (34%) cases. No association was found with patient age, tumour stage, progesterone receptor (PGR) or p53 protein expression. Well-differentiated MBCs tended to be AR positive more often than poorly differentiated ones (P= 0.08). A negative association was found between ARs and cell proliferative activity: MIB-1 scores were higher (25.4%) in AR-negative than in AR-positive cases (21.11%; P= 0.04). A strong positive association (P= 0.0001) was found between ARs and oestrogen receptors (ERs). In univariate analysis, ARs (as well as ERs and PGRs) were not correlated with overall survival; tumour histological grade (P= 0.02), size (P= 0.01), p53 expression (P= 0.0008) and MIB-1 scores (P= 0.0003) had strong prognostic value. In multivariate survival analysis, only p53 expression (P= 0.002) and histological grade (P= 0.02) retained independent prognostic significance. In conclusion, the lack of association between AR and most clinicopathological features and survival, together with the absence of prognostic value for ER/PGR status, suggest that MBCs are biologically different from female breast carcinomas and make it questionable to use antihormonal therapy for patients with MBC. © 1999 Cancer Research Campaig