1,131 research outputs found
How useful is the assessment of lymphatic vascular density in oral carcinoma prognosis?
Abstract
Background
Lymphatic vessels are major routes for metastasis in head and neck squamous cell carcinoma (HNSCC), but lymphatic endothelial cells (LECs) are difficult to recognize in tumor histological sections. D2-40 stains podoplanin, a molecule expressed in LECs, however, the potential prognostic usefulness of this molecule is not completely understood in HNSCC. We aimed to investigate the value of assessing peritumoral and intratumoral lymphatic vessel density (LVD) as prognostic marker for HNSCC.
Methods
Thirty-one cases of HNSCC were stained for D2-40 and CD31. LVD and blood vessel density (BVD) were assessed by counting positive reactions in 10 hotspot areas at Ă200 magnification.
Results
D2-40 was specific for lymphatic vessels and did not stain blood vascular endothelial cells. LECs showed more tortuous and disorganized structure in intratumoral lymphatic vessels than in peritumoral ones. No statistical differences were observed between peritumoral-LVD and intratumoral-LVD or between peritumoral-BVD and intratumoral-BVD. Tumor D2-40 staining was positively associated with lymphatic vessel invasion (p = 0.011).
Conclusion
LVD is a powerful marker for HNSCC prognosis. We found significant differences in peritumoral and intratumoral D2-40 immunoreactivity, which could have important implications in future therapeutic strategies and outcome evaluation
Structure of Metaphase Chromosomes: A Role for Effects of Macromolecular Crowding
In metaphase chromosomes, chromatin is compacted to a concentration of several hundred mg/ml by mechanisms which remain elusive. Effects mediated by the ionic environment are considered most frequently because mono- and di-valent cations cause polynucleosome chains to form compact âŒ30-nm diameter fibres in vitro, but this conformation is not detected in chromosomes in situ. A further unconsidered factor is predicted to influence the compaction of chromosomes, namely the forces which arise from crowding by macromolecules in the surrounding cytoplasm whose measured concentration is 100â200 mg/ml. To mimic these conditions, chromosomes were released from mitotic CHO cells in solutions containing an inert volume-occupying macromolecule (8 kDa polyethylene glycol, 10.5 kDa dextran, or 70 kDa Ficoll) in 100 ”M K-Hepes buffer, with contaminating cations at only low micromolar concentrations. Optical and electron microscopy showed that these chromosomes conserved their characteristic structure and compaction, and their volume varied inversely with the concentration of a crowding macromolecule. They showed a canonical nucleosomal structure and contained the characteristic proteins topoisomerase IIα and the condensin subunit SMC2. These observations, together with evidence that the cytoplasm is crowded in vivo, suggest that macromolecular crowding effects should be considered a significant and perhaps major factor in compacting chromosomes. This model may explain why âŒ30-nm fibres characteristic of cation-mediated compaction are not seen in chromosomes in situ. Considering that crowding by cytoplasmic macromolecules maintains the compaction of bacterial chromosomes and has been proposed to form the liquid crystalline chromosomes of dinoflagellates, a crowded environment may be an essential characteristic of all genomes
Adverse Events Related to the Use of Central Venous Catheters in Hospitalized Newborns
This study identifies the adverse events related to the use of central venous catheters (CVC) in newborns admitted to a neonatal care unit. This is a quantitative, descriptive and retrospective study. The population consisted of 167 newborns admitted in the neonatal unit of the Hospital de ClĂnicas at Porto Alegre, RS, Brazil which used CVCs inserted through percutaneous puncture (PICC) and surgical insertion, totaling 241 catheters. There was a higher prevalence of mechanical adverse events in the PICC line insertions, with a preponderance of catheter occlusions (19.44%) and ruptures (8.8%). The surgically inserted CVCs had a higher prevalence of catheter-related infectious adverse events with the most common being clinical sepsis (16%). This study suggests that the correct insertion technique should be used and a specialized team should monitor the CVCs to ensure safety and prevent adverse events.El objetivo de este estudio fue identificar los eventos adversos relacionados con el uso de catĂ©teres venosos centrales (CVC), en reciĂ©n nacidos internados en una unidad neonatal. Se trata de investigaciĂłn cuantitativa, descriptiva, retrospectiva. La poblaciĂłn fue constituida por 167 neonatos internados en la unidad neonatal del Hospital de ClĂnicas de Porto Alegre que utilizaron CVCs, inseridos por punciĂłn percutĂĄnea (PICC) e inserciĂłn quirĂșrgica, totalizando 241 catĂ©teres. En los PICCs hubo mayor incidencia de eventos adversos mecĂĄnicos, predominando la oclusiĂłn (19,44%) y la ruptura del catĂ©ter (8,8%). Los CVCs por inserciĂłn quirĂșrgica presentaron la mayor incidencia de los eventos adversos infecciosos relacionados al catĂ©ter, siendo el mĂĄs frecuente la sepsis clĂnica (16%). El estudio sugiere que, para mayor seguridad del uso de CVCs, es importante que sea utilizada la tĂ©cnica correcta de inserciĂłn del catĂ©ter y realizado el acompañamiento de los CVCs por un equipo especializado y atento a la prevenciĂłn de eventos adversos.O objetivo deste estudo foi identificar os eventos adversos relacionados ao uso de cateteres venosos centrais (CVC), em recĂ©m-nascidos internados em unidade neonatal. Trata-se de pesquisa quantitativa, descritiva, retrospectiva. A população foi constituĂda por 167 neonatos internados na unidade neonatal do Hospital de ClĂnicas de Porto Alegre que utilizaram CVCs, inseridos por punção percutĂąnea (PICC) e inserção cirĂșrgica, totalizando 241 cateteres. Nos PICCs houve maior prevalĂȘncia de eventos adversos mecĂąnicos, predominando a oclusĂŁo (19,44%) e a ruptura do cateter (8,8%). Os CVCs por inserção cirĂșrgica apresentaram maior prevalĂȘncia dos eventos adversos infecciosos relacionados ao cateter, sendo o mais frequente a sepse clĂnica (16%). O estudo sugere que, para maior segurança do uso de CVCs, Ă© importante que seja utilizada a tĂ©cnica correta de inserção do cateter e realizado o acompanhamento dos CVCs por equipe especializada e atenta para a prevenção de eventos adversos
Functional Polymorphisms in IL13 Are Protective against High Schistosoma mansoni Infection Intensity in a Brazilian Population
IL-13 is a signature cytokine of the helper T cell type 2 (TH2) pathway which underlies host defense to helminthic infection and activates production of IgE in both parasitized populations and in urban settings after allergen exposure.Two functional polymorphisms in IL13, rs1800925 (or c.1-1111C>T) and rs20541 (or R130Q) were previously found to be associated with Schistosoma hematobium infection intensity. They have not been thoroughly explored in S. mansoni-endemic populations, however, and were selected along with 5 tagging SNPs for genotyping in 812 individuals in 318 nuclear families from a schistosomiasis-endemic area of Conde, Bahia, in Brazil. Regression models using GEE to account for family membership and family-based quantitative transmission disequilibrium tests (QTDT) were used to evaluate associations with total serum IgE (tIgE) levels and S. mansoni fecal egg counts adjusted for non-genetic covariates. We identified a protective effect for the T allele at rs20541 (Pâ=â0.005) against high S. mansoni egg counts, corroborated by QTDT (Pâ=â0.014). Our findings also suggested evidence for protective effects for the T allele at rs1800925 and A allele at rs2066960 after GEE analysis only (Pâ=â0.050, 0.0002).The two functional variants in IL13 are protective against high S. mansoni egg counts. These markers showed no evidence of association with tIgE levels, unlike tIgE levels previously studied in non-parasitized or atopic study populations
Search for rare quark-annihilation decays, B --> Ds(*) Phi
We report on searches for B- --> Ds- Phi and B- --> Ds*- Phi. In the context
of the Standard Model, these decays are expected to be highly suppressed since
they proceed through annihilation of the b and u-bar quarks in the B- meson.
Our results are based on 234 million Upsilon(4S) --> B Bbar decays collected
with the BABAR detector at SLAC. We find no evidence for these decays, and we
set Bayesian 90% confidence level upper limits on the branching fractions BF(B-
--> Ds- Phi) Ds*- Phi)<1.2x10^(-5). These results
are consistent with Standard Model expectations.Comment: 8 pages, 3 postscript figues, submitted to Phys. Rev. D (Rapid
Communications
Observation of associated near-side and away-side long-range correlations in âsNN=5.02ââTeV proton-lead collisions with the ATLAS detector
Two-particle correlations in relative azimuthal angle (ÎÏ) and pseudorapidity (Îη) are measured in âsNN=5.02ââTeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1ââÎŒb-1 of data as a function of transverse momentum (pT) and the transverse energy (ÎŁETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Îη|<5) ânear-sideâ (ÎÏâŒ0) correlation that grows rapidly with increasing ÎŁETPb. A long-range âaway-sideâ (ÎÏâŒÏ) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ÎŁETPb, is found to match the near-side correlation in magnitude, shape (in Îη and ÎÏ) and ÎŁETPb dependence. The resultant ÎÏ correlation is approximately symmetric about Ï/2, and is consistent with a dominant cosâĄ2ÎÏ modulation for all ÎŁETPb ranges and particle pT
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