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We report results from an analysis aimed at detecting the trispectrum of the kinematic Sunyaev-Zel'dovich (kSZ) effect by combining data from the South Pole Telescope (SPT) and Herschel-SPIRE experiments over a 100 deg^{2} field. The SPT observations combine data from the previous and current surveys, namely SPTpol and SPT-3G, to achieve depths of 4.5, 3, and 16 µK-arcmin in bands centered at 95, 150, and 220 GHz. For SPIRE, we include data from the 600 and 857 GHz bands. We reconstruct the velocity-induced large-scale correlation of the small-scale kSZ signal with a quadratic estimator that uses two cosmic microwave background (CMB) temperature maps, constructed by optimally combining data from all the frequency bands. We reject the null hypothesis of a zero trispectrum at 10.3σ level. However, the measured trispectrum contains contributions from both the kSZ and other undesired components, such as CMB lensing and astrophysical foregrounds, with kSZ being sub-dominant. We use the agora simulations to estimate the expected signal from CMB lensing and astrophysical foregrounds. After accounting for the contributions from CMB lensing and foreground signals, we do not detect an excess kSZ-only trispectrum and use this nondetection to set constraints on reionization. By applying a prior based on observations of the Gunn-Peterson trough, we obtain an upper limit on the duration of reionization of Δz_{re,50}<4.5 (95% confidence level). We find these constraints are fairly robust to foregrounds assumptions. This trispectrum measurement is independent of, but consistent with, Planck's optical depth measurement. This result is the first constraint on the epoch of reionization using the non-Gaussian nature of the kSZ signal.
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We report the first detection of gravitational lensing due to galaxy clusters using only the polarization of the cosmic microwave background (CMB). The lensing signal is obtained using a new estimator that extracts the lensing dipole signature from stacked images formed by rotating the cluster-centered Stokes QU map cutouts along the direction of the locally measured background CMB polarization gradient. Using data from the SPTpol 500 deg^{2} survey at the locations of roughly 18 000 clusters with richness λ≥10 from the Dark Energy Survey (DES) Year-3 full galaxy cluster catalog, we detect lensing at 4.8σ. The mean stacked mass of the selected sample is found to be (1.43±0.40)×10^{14}M_{â} which is in good agreement with optical weak lensing based estimates using DES data and CMB-lensing based estimates using SPTpol temperature data. This measurement is a key first step for cluster cosmology with future low-noise CMB surveys, like CMB-S4, for which CMB polarization will be the primary channel for cluster lensing measurements.
Assuntos
Hemorragia Gastrointestinal , Perfuração Intestinal , Humanos , Colite/complicações , Colite/diagnóstico , Colite/etiologia , Colonoscopia , Impacção Fecal/complicações , Impacção Fecal/diagnóstico por imagem , Hemorragia Gastrointestinal/etiologia , Perfuração Intestinal/etiologia , Perfuração Intestinal/cirurgia , Perfuração Intestinal/diagnóstico por imagem , Tomografia Computadorizada por Raios XRESUMO
We report the results of a joint analysis of data from BICEP2/Keck Array and Planck. BICEP2 and Keck Array have observed the same approximately 400 deg^{2} patch of sky centered on RA 0 h, Dec. -57.5°. The combined maps reach a depth of 57 nK deg in Stokes Q and U in a band centered at 150 GHz. Planck has observed the full sky in polarization at seven frequencies from 30 to 353 GHz, but much less deeply in any given region (1.2 µK deg in Q and U at 143 GHz). We detect 150×353 cross-correlation in B modes at high significance. We fit the single- and cross-frequency power spectra at frequencies ≥150 GHz to a lensed-ΛCDM model that includes dust and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r), using a prior on the frequency spectral behavior of polarized dust emission from previous Planck analysis of other regions of the sky. We find strong evidence for dust and no statistically significant evidence for tensor modes. We probe various model variations and extensions, including adding a synchrotron component in combination with lower frequency data, and find that these make little difference to the r constraint. Finally, we present an alternative analysis which is similar to a map-based cleaning of the dust contribution, and show that this gives similar constraints. The final result is expressed as a likelihood curve for r, and yields an upper limit r_{0.05}<0.12 at 95% confidence. Marginalizing over dust and r, lensing B modes are detected at 7.0σ significance.
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Gravitational lensing of the cosmic microwave background generates a curl pattern in the observed polarization. This "B-mode" signal provides a measure of the projected mass distribution over the entire observable Universe and also acts as a contaminant for the measurement of primordial gravity-wave signals. In this Letter we present the first detection of gravitational lensing B modes, using first-season data from the polarization-sensitive receiver on the South Pole Telescope (SPTpol). We construct a template for the lensing B-mode signal by combining E-mode polarization measured by SPTpol with estimates of the lensing potential from a Herschel-SPIRE map of the cosmic infrared background. We compare this template to the B modes measured directly by SPTpol, finding a nonzero correlation at 7.7σ significance. The correlation has an amplitude and scale dependence consistent with theoretical expectations, is robust with respect to analysis choices, and constitutes the first measurement of a powerful cosmological observable.
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The cosmic microwave background (CMB) B-mode signal is potentially weaker than the diffuse Galactic foregrounds over most of the sky at any frequency. A common method of separating the CMB from these foregrounds is via pixel-based parametric-model fitting. There are not currently enough all-sky maps to fit anything more than the most simple models of the sky. By simulating the emission in seven representative pixels, we demonstrate that the inclusion of a 5 GHz data point allows for more complex models of low-frequency foregrounds to be fitted than at present. It is shown that the inclusion of the C-BASS data will significantly reduce the uncertainties in a number of key parameters in the modelling of both the galactic foregrounds and the CMB. The extra data allow estimates of the synchrotron spectral index to be constrained much more strongly than is presently possible, with corresponding improvements in the accuracy of the recovery of the CMB amplitude. However, we show that to place good limits on models of the synchrotron spectral curvature will require additional low-frequency data.
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Although end-stage liver disease (ESLD) is often associated with splenomegaly and thrombocytopenia, splenectomy is not necessary in liver transplantation (OLT) except in special situations. In this paper, we examined the indications for splenectomy in the era of living-donor living transplantation. Six of 46 patients underwent splenectomies. Among them, one received a cadaveric graft. Three splenectomies were performed at 6, 7, and 44 days after OLT because of a huge spleen, massive ascites, or impaired liver function. The other two patients received simultaneous splenectomy during OLT to prevent rejection of ABO-incompatible grafts with a positive anti-T-cell test; and one, for postoperative therapy of hepatitis C. All six patients had a good response to splenectomy. We concluded that splenectomy may be indicated for recipients with severe thrombocytopenia, small-for-size syndrome, ABO incompatibility with positive anti-T/B-cell tests and post-OLT therapy for hepatitis C.
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Falência Hepática/cirurgia , Transplante de Fígado/estatística & dados numéricos , Doadores Vivos , Esplenomegalia/cirurgia , Adulto , Bilirrubina/sangue , Cadáver , Feminino , Humanos , Falência Hepática/complicações , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos , Esplenomegalia/epidemiologia , Doadores de Tecidos , Resultado do TratamentoRESUMO
Natural killer (NK) cells play a crucial role in regulating immune functions. Few studies have characterized canine NK cells. We previously demonstrated that canine peripheral blood lymphocytes (PBLs) with a low surface CD5 density (CD5lo) are considered a critical NK population. Natural killer cells in most mammals do not express T-cell markers, but canine CD5lo cells express surface molecules, such as CD3 T-cell receptors. These features make canines unique models for the study of comparative immunology in NK cells. In this study, we discovered that CD5lo and CD21 double-negative (CD5lo-ne/CD2-) cells were originally low in NK cytotoxicity and their NK cytotoxicity was highly activated when co-cultured with CD5lo NK cells. The cytotoxicity was not activated when co-cultured with other cell types, such as high surface CD5 density (CD5hi) cells. The CD5lo-negative (CD5lo-ne) population comprises CD5- and CD5hi cells. CD5-cells were low in NK cytotoxicity initially or after culturing with interleukin-2 (IL-2) without CD5lo cells; however, the addition of CD5lo cells in a similar medium markedly enhanced the NK activity. By contrast, CD5hi cells were always NK inactive, irrespective of them being cultured with CD5lo cells or not. We further verified that only the CD5-CD21- cells, which were separated from CD5-CD21+ cells in the entire CD5- population, showed activated NK activity through CD5lo cell induction. This study is the first to reveal that canine NK cells enhanced NK-inert cells to become NK-cytotoxic cells. Additionally, it is concluded that in beagles, except for CD5lo cells, CD5-CD21- cells show NK activity.
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OBJECTIVE: Plasma B-group vitamins and age may affect the carotid intima-media thickness (IMT) in subjects with different 677TT genotype of the methylenetetrahydrofolate reductase (MTHFR) gene. DESIGN: A hospital-based cross-study. SETTING: Genomic and Vascular Center, Changhua Christian Hospital, Changhua, Taiwan. SUBJECTS: Five hundred and forty-one clinically healthy subjects. INTERVENTION: Fasting plasma, homocysteine (Hcy), vitamin B(6), vitamin B(12), folate and B-mode carotid ultrasound. RESULTS: MTHFR genotype, plasma concentrations of folate, vitamin B(6) and vitamin B(12) and age were significantly correlated to the plasma Hcy concentration. MTHFR 677TT carriers had higher concentrations of Hcy than did subjects with the CC and CT genotypes. Age, sex, body mass index and plasma Hcy were independent contributors to increase carotid IMT. However, with stratification by mean value of age and B-group vitamins concentrations, we found that at advanced age, lower plasma folate and vitamin B(12) were three risk factors involved in the enhancing effect of the MTHFR 677TT genotype on the increase of plasma Hcy and carotid IMT. CONCLUSION: MTHFR 677TT-related carotid atherosclerosis was only identified in healthy elderly subjects with lower level of plasma folate and vitamin B(12). SPONSORSHIP: Changhua Christian Hospital.
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Carbono-Nitrogênio Ligases/genética , Artérias Carótidas/patologia , Doenças das Artérias Carótidas/genética , Polimorfismo Genético , Túnica Íntima/patologia , Complexo Vitamínico B/sangue , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Doenças das Artérias Carótidas/sangue , Estudos Transversais , Feminino , Ácido Fólico/sangue , Genótipo , Homocisteína/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Sexuais , Vitamina B 12/sangueRESUMO
PURPOSE: The purpose of this study was to evaluate the efficacy and safety of the anterior Kugel herniorrhaphy approach when the onlay patch is omitted. METHODS: The study population comprised patients who underwent anterior Kugel herniorrhaphy without the onlay patch from 1 May 2009, to 31 June 2012. The onlay patch was omitted if the posterior wall defect did not exceed the inner Posiflex(®) ring diameter. After reviewing the clinical follow-up records and conducting telephone interviews, the postoperative results were recorded and analyzed. RESULTS: A total of 163 patients underwent 175 hernia repairs. One patient developed recurrence after undergoing our herniorrhaphy method. The most common postoperative complaints were mild soreness, indescribable discomfort, and foreign body sensations (11 patients). The mean operative time and hospital stay were 67 min and 2 days, respectively. More serious complications included one scrotal hematoma, one hydrocele, and one wound infection that resulted in epididymitis. CONCLUSIONS: The onlay patch can be omitted with low recurrence and complication rates if the posterior wall defects do not exceed the inner Posiflex(®) ring diameter.
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Hérnia Inguinal/cirurgia , Telas Cirúrgicas , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Herniorrafia , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Resultado do Tratamento , Adulto JovemRESUMO
Benzophenone is an ultraviolet (UV)-absorbing agent that has been used in industry and medicine for more than 30 years. Consumers of cosmetics and sunscreens containing UV-absorbers are exposed to benzophenones on a daily basis, owing to the widespread use of these compounds. However, the efficacy of these compounds as scavengers of oxidative stress is still not well established. In the present study, we investigate the antioxidative capacity of six sunscreen benzophenone compounds. A primary myoblast culture was mixed in vitro with 100 microM menadione. The cytotoxic effect by menadione-induced oxidative stress was monitored by the lucigenin- or luminol-amplified chemiluminescence, methylthiotetrazole (MTT) assay, and the antioxidative effects of various benzophenone compounds were evaluated. The results showed that the addition of menadione can induce oxidative stress on myoblasts by superoxide and hydrogen peroxide production, which can be eradicated by superoxide dismutase (SOD) and catalase, respectively, in a dose-dependent mode. The catalase has a protective effect on the cytotoxicity induced by menadione as measured by the MTT assay, while the SOD does not. The selected benzophenones also have a significant scavenging effect on the menadione-induced cell death on the myoblasts. The ortho-dihydroxyl structure and other hydroxy groups in the same ring have a stronger scavenging effect on the superoxide anion on myoblasts; thus, a stable penoxy radical may be formed. The mechanism of this effect remains to be clarified.
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Benzofenonas/farmacologia , Sequestradores de Radicais Livres/farmacologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Acridinas , Animais , Sobrevivência Celular/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Humanos , Técnicas In Vitro , Medições Luminescentes , Luminol , Músculo Esquelético/citologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Protetores Solares/farmacologia , Superóxido Dismutase/farmacologia , Sais de Tetrazólio , Tiazóis , Vitamina K/toxicidadeRESUMO
The antitumor effect of green tea polyphenols has been well characterized in numerous papers. However, the mechanism of their action is still poorly defined. In this study, epigallocatechin gallate (EGCG), the main ingredient of green tea extract, was studied for its effect on the expression of glutathione S-transferases (GSTs) in rat liver to examine the mechanism of action. Liver samples were collected from Sprague-Dawley rats treated with EGCG in H(2)O by portal vein perfusion and examined for total GST activity and GST expression. The results showed that the induction of GST activity by EGCG was dose- and time-dependent. GST activity was increased about 28-fold at 12 hr after treatment. Three GST subunits (GSTA1/2, GSTM1, and GSTM2) were examined by Western blot for changes in protein level affected by EGCG (1 mg/kg weight). Only GSTM2 revealed a significant time-dependent increase, with a maximal induction of approximately 2.0-fold. The differential effect of EGCG on GST subunit expression was also verified by immunocytochemical examination and showed strong induction of the GSTM2 (but not the GSTA1/2 and GSTM1) level in liver section. This induction occurred as early as 3 hr after treatment and extended gradually outward from the hepatic veins as treatment time increased. The change in the GSTM2 protein level was accompanied by a corresponding alteration in mRNA quantity ( approximately 2.0-fold of control). Our report is the first to demonstrate a specific induction of the GSTM2 subunit by a chemopreventor and suggests a primary influence of EGCG on GSTM2 gene expression.
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Catequina/farmacologia , Glutationa Transferase/biossíntese , Fígado/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Catequina/análogos & derivados , Indução Enzimática , Expressão Gênica/efeitos dos fármacos , Glutationa Transferase/genética , Imuno-Histoquímica , Técnicas In Vitro , Isoenzimas/biossíntese , Fígado/enzimologia , Masculino , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-DawleyRESUMO
A case of complicated spontaneous esophageal perforation is presented. The control of gastroesophageal reflux by esophageal banding appears to be a crucial factor in healing. Using a modified esophageal exclusion technique without sacrifice of the esophagus proves to be both effective and lifesaving.
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Perfuração Esofágica/cirurgia , Esôfago/cirurgia , Refluxo Gastroesofágico/prevenção & controle , Cateterismo , Drenagem , Empiema/cirurgia , Perfuração Esofágica/complicações , Esôfago/diagnóstico por imagem , Humanos , Jejuno/cirurgia , Pulmão/cirurgia , Masculino , Pessoa de Meia-Idade , RadiografiaRESUMO
Finite element method (FEM) has been extensively used for evaluating interfacial status inside biomaterials. This study using FEM was designed to evaluate the thermal stress behavior of a filler-matrix interface. The results were then compared to those of a previous study obtained by a laser thermoacoustic technique (LTAT). The experimental systems (75/25 Bis-GMA/TEGDMA resin reinforced with 0, 25, 50, and 75 wt% 8-microm silanized/unsilanized BaSiO6) as used in the previous study were modeled in this study. The established finite element models were based on coefficient of thermal expansion (CTE) Mismatch Phenomenon. The mechanical properties of the silane coupling agent, such as elastic modulus and thermal expansion coefficient used in the silanized model, were assumed to have optimal heat flux transfer. A third (imaginary) material was proposed to block the transfer of thermal stress between the filler and matrix in the unsilanized model. The thermal load simulation was based on steady-state thermal analysis. The results showed that: (1) The strain energy and interfacial shearing stress calculated from FEM validate the results from the previous LTAT study. (2) Comparing the stress distribution of silanized and unsilanized FEM models, the acoustic signals in LTAT study are mainly derived from debonding of the filler-matrix interface of silanized specimens, and from the matrix area of unsilanized specimens. Based on results to date, we conclude that the finite element method may be a powerful tool for exploring thermoacoustic mechanisms of dental composites.
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Compostos de Bário/química , Resinas Compostas/química , Temperatura Alta , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Silicatos/química , Acústica , Elasticidade , Lasers , Teste de Materiais , Matemática , Microscopia Eletrônica de Varredura , Estresse MecânicoRESUMO
The finite element method (FEM) has been extensively used in evaluating the interfacial status of biomaterials. We used FEM to explore the microscopic debonding mechanism of the dentin/hybrid layer/resin adhesive interface. The stress status of the local material was used as an index to judge whether the adhesive interface would develop a debonding mechanism. To generate the local stress concentration, the thermal boundary condition was applied to the model which has the phenomenon of the coefficient of thermal expansion (CTE) mismatch. The thermal boundary condition was used to emulute a previous study conducted with a laser thermoacoustic technique (LTAT). The materials, Scotchbond MP, Optibond, and Tenure bonding systems, used in the previous experiment were also tested in this study. The results show that interfacial debonding in the finite element model occurred through the hybrid layer for both the Scotchbond MP and Tenure systems, as well as within the adhesive layer itself for the Optibond system. These findings are compatible with observations by SEM obtained by LTAT. Another transformed model was created to test the "elastic cavity wall" concept. The result also confirms the importance of the elastic cavity wall concept. These compatible results between FEM and LTAT indicate that FEM can be a very useful supplement to thermoacoustic testing.
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Materiais Biocompatíveis/química , Adesivos Dentinários/química , Dentina , Temperatura Alta , Microscopia Eletrônica de Varredura , Cimentos de Resina/química , Estresse Mecânico , Relação Estrutura-Atividade , TermodinâmicaRESUMO
Esculetin(4), umbelliferone(7-hydroxycoumarin)(3) and 7-hydroxy-4-methyl coumarin(8) are strong xanthine oxidase inhibitors (IC50 = 20.91, 43.65 and 96.70 microM respectively). Based on this observation, the structure of 7-hydroxy coumarin(3) plays a very important role in xanthine oxidase (XO) inhibition. The 6-hydroxy group present in the molecule of 7-hydroxy coumarin, e.g. esculetin(4) enhanced the activity, whereas substitution by the 6-methoxy group, e.g. scopoletin (5), reduced the inhibitory effect. Furthermore, 6-glycoside group present in the molecule of 7-hydroxy coumarin, e.g. esculin (6,7-dihydroxy coumarin 6-glucoside)(12) strongly decreased the inhibitory effect as well as scoparone(6), the fully methylated derivative of esculetin (4). In contrast to 7-hydroxy coumarin(3), however, 4-hydroxy coumarin(13) showed only a weak effect on XO inhibition. 4-Substituent present in the molecule of 7-hydroxycoumarin also reduced the activity but the degree of reduction depended on the substituents: 7-hydroxy-4-methylcoumarin (8) < 7-hydroxycoumarin-4-acetic acid (7) < 7-hydroxy-4-trifluoromethylcoumarin (9). Their percent inhibition at 100 microM was 62.47, 38.46 and 26.84% respectively. 8-substituent present in the molecule of 7-hydroxy coumarin (3), such as 7,8-dihydroxy-6-methoxycoumarin(10) and fraxin(7-hydroxy-6-methoxycoumarin 8-glucoside)(11) reduced the activity as compared with scopoletin (5). Their percent inhibition at 100 microM was 18.4 and 6.9% respectively, which indicated that the more bulky the 8-substituted in the structure, the weaker the inhibitory activity on XO. 3,4,8-Trimethyl-7-hydroxycoumarin(14) which substitution by the methyl at 3,4 & 8 in the structure of 7-hydroxycoumarin(3) also reduced the activity as compared with 7-hydroxycoumarin(3). It seems that the double bond in the structure of coumarin(1) played an important role in the activity as compared with coumarin(dihydrocoumarin)(2). The apparent inhibition constants(Ki) of esculetin(4), umbelliferone (3) and 7-hydroxy-4-methylcoumarin(8) were 2.056, 21.683 and 4.86 microM respectively and induced competitive, uncompetitive and a mixed type of inhibition of the enzyme with respect to the substrate xanthine.
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Cumarínicos/farmacologia , Xantina Oxidase/antagonistas & inibidores , Relação Estrutura-AtividadeRESUMO
Eighteen anthraquinones and related compounds were tested for their inhibitory effects on xanthine oxidase. The enzyme, xanthine oxidase catalyses the oxidation of hypoxanthine to xanthine and of xanthine to uric acid, which has a lambda max of 295nm, forming the basis for a spectrophotometric assay of the activity of xanthine oxidase. The results showed that anthrarobin and purpurin showed moderate effects on xanthine oxidase inhibition (IC50 = 68.35 and 105.13 microM; Ki = 122.38 and 130.49 microM respectively), and both of them induced mixed type (competitive-non-competitive) inhibition with respect to the substrate xanthine.