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1.
Chemistry ; 30(4): e202303718, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-37955413

RESUMO

On one hand electron or hole doping of quantum spin liquid (QSL) may unlock high-temperature superconductivity and on the other hand it can disrupt the spin liquidity, giving rise to a magnetically ordered ground state. Recently, a 2D MOF, Cu3 (HHTP)2 (HHTP - 2,3,6,7,10,11-hexahydroxytriphenylene), containing Cu(II) S= 1 / 2 ${{ 1/2 }}$ frustrated spins in the Kagome lattice is emerging as a promising QSL candidate. Herein, we present an elegant in situ redox-chemistry strategy of anchoring Cu3 (HHTP)2 crystallites onto diamagnetic reduced graphene oxide (rGO) sheets, resulting in the formation of electron-doped Cu3 (HHTP)2 -rGO composite which exhibited a characteristic semiconducting behavior (5 K to 300 K) with high electrical conductivity of 70 S ⋅ m-1 and a carrier density of ~1.1×1018  cm-3 at 300 K. Remarkably, no magnetic transition in the Cu3 (HHTP)2 -rGO composite was observed down to 1.5 K endorsing the robust spin liquidity of the 2D MOF Cu3 (HHTP)2 . Specific heat capacity measurements led to the estimation of the residual entropy values of 28 % and 34 % of the theoretically expected value for the pristine Cu3 (HHTP)2 and Cu3 (HHTP)2 -rGO composite, establishing the presence of strong quantum fluctuations down to 1.5 K (two times smaller than the value of the exchange interaction J).

2.
Inorg Chem ; 63(8): 3675-3681, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38362775

RESUMO

Two-dimensional metal-organic frameworks (2D MOFs) are emerging as a new class of multifunctional materials for diversified applications, although magnetic properties have not been widely explored. The metal ions and organic ligands in some of the 2D MOFs are arranged in the well-known Kagome lattice, leading to geometric spin frustration. Hence, such systems could be the potential candidates to exhibit an exotic quantum spin liquid (QSL) state, as was observed in Cu3(HHTP)2 (HHTP = hexahydroxytriphenylene), with no magnetic transition down to 38 mK. Hereto, we have investigated the spin intertwining in a bimetallic 2D MOF system, M3(HHTP)2 (M = Cu/Zn), arising from the localized (d-electron) and delocalized (π-electron) S = 1/2 spins from the Cu(II) ions and the HHTP radicals, respectively. The origin of the spin frustration (down to 5K) was critically examined by varying the metal composition in bimetallic systems, CuxZn3-x(HHTP)2 (x = 1, 1.5, 2), containing both S = 1/2 and S = 0 spins. Additionally, to gain a deeper understanding, we studied the spin interaction in the pristine Zn3(HHTP)2 system containing only S = 0 Zn(II) ions. In view of the quantitative estimate of the localized and delocalized spins, the d-π spin correlation appears essential in understanding the unusual magnetic and/or other physical properties of such hybrid organic-inorganic 2D crystalline solids.

3.
Mol Carcinog ; 59(3): 323-332, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31943365

RESUMO

Approximately, 30 000 men die from prostate cancer (PCa) every year in the United States, mainly due to the metastasis. Thus, the key events associated with PCa metastasis are under rigorous investigation, with recent studies showing that preparation of pre-metastatic niches (PMN) in distant organs is an important step. However, the molecular basis for PMN preparation is still unclear. Hypoxia in primary tumors promotes aggressiveness; however, its precise role in metastasis is not clear. We recently reported that exosomes secreted by PCa cells under hypoxia promote stemness and invasiveness in naïve PCa cells; however, whether these extracellular vesicles also influence PMN remains unknown. In the present study, we isolated exosomes from human PCa PC3 cells under normoxic (21% O2 , exosomes secreted under normoxic condition [ExoNormoxic ]) and hypoxic (1% O2 , exosomes secreted under hypoxic condition [ExoHypoxic ]) conditions, and characterized their effect (10 µg exosomes, intraperitoneal (IP) treatment every 48 hours for 4 weeks) on key biomarkers associated with PMN in nude mice. Whole animal fluorescence imaging showed that ExoHypoxic treatment promotes matrix metalloproteinases (MMPs) activity in several putative metastatic sites. Histological studies confirmed that ExoHypoxic treatment enhanced the level of MMP2, MMP9, and extracellular matrix proteins (fibronectin and collagen) as well as increased the number of CD11b+ cells at selective PMN sites. Furthermore, proteomic profiling of exosomes by liquid chromatography/mass spectrometry identified cargo proteins in ExoNormoxic and ExoHypoxic as well as distinct canonical pathways targeted by them. These results suggest that exosomes secreted by PCa cells under hypoxia plausibly remodel distant PMN, and thus, could be a potential target to control metastatic PCa.


Assuntos
Exossomos/metabolismo , Metaloproteinases da Matriz/metabolismo , Neoplasias da Próstata/metabolismo , Animais , Ativação Enzimática , Exossomos/patologia , Humanos , Masculino , Camundongos Nus , Metástase Neoplásica/patologia , Células PC-3 , Próstata/citologia , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/patologia , Hipóxia Tumoral
4.
Inorg Chem ; 59(9): 6214-6219, 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32302106

RESUMO

Study on magnetism in two-dimensional (2D) spin-lattices is advancing rapidly. In this work, phase-pure botallackite (Bo) (Cu2(OH)3Br), a quasi-2D S = 1/2 anisotropic triangular spin-lattice is stabilized over 2D reduced graphene oxide (rGO) nanosheets via simple oxidation-reduction reaction chemistry. In comparison to polycrystalline Bo, such an anchoring resulted in the oriented growth of Bo crystallites in the Bo-rGO system. The Bo-rGO nanocomposite was found to be magnetically active with a Néel transition at ∼8.9 K, crossing over to possible XY anisotropy at ∼5 K-as revealed by complementary dc and ac susceptibility measurements-an unprecedented observation in the field assigned to an interfacial effect. This work demonstrates the potential usage of nonmagnetic 2D functionalized graphene to significantly modulate the magnetic properties of 2D spin-lattices.

5.
N Engl J Med ; 375(24): 2359-2368, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27771985

RESUMO

BACKGROUND: We previously reported that there was no significant difference at 30 days or at 1 year in the rate of the composite outcome of death, stroke, myocardial infarction, or renal failure between patients who underwent coronary-artery bypass grafting (CABG) performed with a beating-heart technique (off-pump) and those who underwent CABG performed with cardiopulmonary bypass (on-pump). We now report the results at 5 years (the end of the trial). METHODS: A total of 4752 patients (from 19 countries) who had coronary artery disease were randomly assigned to undergo off-pump or on-pump CABG. For this report, we analyzed a composite outcome of death, stroke, myocardial infarction, renal failure, or repeat coronary revascularization (either CABG or percutaneous coronary intervention). The mean follow-up period was 4.8 years. RESULTS: There were no significant differences between the off-pump group and the on-pump group in the rate of the composite outcome (23.1% and 23.6%, respectively; hazard ratio with off-pump CABG, 0.98; 95% confidence interval [CI], 0.87 to 1.10; P=0.72) or in the rates of the components of the outcome, including repeat coronary revascularization, which was performed in 2.8% of the patients in the off-pump group and in 2.3% of the patients in the on-pump group (hazard ratio, 1.21; 95% CI, 0.85 to 1.73; P=0.29). The secondary outcome for the overall period of the trial - the mean cost in U.S. dollars per patient - also did not differ significantly between the off-pump group and the on-pump group ($15,107 and $14,992, respectively; between-group difference, $115; 95% CI, -$697 to $927). There were no significant between-group differences in quality-of-life measures. CONCLUSIONS: In our trial, the rate of the composite outcome of death, stroke, myocardial infarction, renal failure, or repeat revascularization at 5 years of follow-up was similar among patients who underwent off-pump CABG and those who underwent on-pump CABG. (Funded by the Canadian Institutes of Health Research; CORONARY ClinicalTrials.gov number, NCT00463294 .).


Assuntos
Ponte de Artéria Coronária sem Circulação Extracorpórea , Ponte de Artéria Coronária/métodos , Idoso , Ponte de Artéria Coronária/economia , Doença da Artéria Coronariana/mortalidade , Doença da Artéria Coronariana/cirurgia , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Complicações Pós-Operatórias/epidemiologia , Modelos de Riscos Proporcionais , Qualidade de Vida , Insuficiência Renal/etiologia , Reoperação/estatística & dados numéricos , Acidente Vascular Cerebral/etiologia
6.
Mol Carcinog ; 58(7): 1260-1271, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30912211

RESUMO

Around 80% of nonmelanoma skin cancers (NMSCs) are basal cell carcinoma (BCC), still studies evaluating the efficacy of chemopreventive agents during early stage/s of BCC development are lacking. Accordingly, utilizing the well-established patched (Ptch)+/- mouse model of ultraviolet B (UVB) radiation-induced BCC formation, we excised skin samples from UVB exposed Ptch+/- and Ptch+/+ mice before tumor formation to study the promotion/progression of BCC and to determine the efficacy and target/s of silibinin, a well-known skin cancer chemopreventive agent. UVB exposure for 1 month increased the number of mast cells in Ptch+/- mice by ~48% (P < 0.05), which was completely inhibited by silibinin. Polymerase chain reaction profiler array analysis of skin samples showed strong molecular differences between Ptch+/+ and Ptch+/- mice which were either unexposed or UVB irradiated+/- silibinin treatment. Most notably, silibinin treatment significant decreased the expression of BMP-2, Bbc3, PUMA, and Ccnd1 in Ptch+/- mice irradiated with silibinin + UVB. Additional studies showed that silibinin targets UVB-induced expression of bone morphogenetic protein 2 (BMP-2) in Ptch+/- mouse skin. Last, our studies found that silibinin strongly attenuates UVB-induced BMP-2 expression and DNA damage in Ptch+/- mouse skin ex vivo only after single UVB exposure. Together, our results suggest a possible role of mast cell recruitment and BMP-2 activation in the early stages of BCC development; these are strongly inhibited by silibinin suggesting its possible chemopreventive efficacy against BCC formation in long-term UVB exposure regimen.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proteína Morfogenética Óssea 2/biossíntese , Carcinoma Basocelular/tratamento farmacológico , Mastócitos/efeitos da radiação , Receptor Patched-1/genética , Silibina/farmacologia , Neoplasias Cutâneas/tratamento farmacológico , Raios Ultravioleta/efeitos adversos , Animais , Proteínas Reguladoras de Apoptose/biossíntese , Carcinoma Basocelular/patologia , Quimioprevenção , Ciclina D1/biossíntese , Dano ao DNA/efeitos dos fármacos , Modelos Animais de Doenças , Mastócitos/patologia , Camundongos , Camundongos Transgênicos , Transdução de Sinais , Pele/patologia , Neoplasias Cutâneas/patologia , Proteínas Supressoras de Tumor/biossíntese
7.
J Foot Ankle Surg ; 58(3): 502-507, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30685424

RESUMO

Displaced intra-articular calcaneal fractures can be difficult to treat. Open surgical techniques are associated with wound complications, whereas nonoperative management leads to arthrosis. In the present study, 23 displaced intra-articular calcaneal fractures in 19 patients were treated with closed reduction and percutaneous Kirschner wire fixation. Sanders and Essex-Lopresti classification systems were used. We studied anatomical (Gissane and Bohler angles and width of calcaneus) and functional (Maryland Foot Score and American Orthopaedic Foot and Ankle Society Ankle-Hindfoot Score) outcomes after 6, 18, and 26 months. Mechanism of injury, fluoroscopy use, time since injury, time delay to surgery, method of reduction, and number of Kirschner wires used were recorded. The mean participant age was 29.5 (17 to 46) years, mean delay to surgery was 7 (2 to 12) days, mean length of surgery was 61 (range 20 to 175) minutes, and mean fluoroscopy time was 115 (range 20 to 254) seconds. All patients were followed for a minimum of 26 months, and the mean duration of follow-up was 32.4 (26 to 36) months. There were 18 (78.26%) joint depression and 5 (21.74%) tongue-type fractures, whereas there were 2 (8.69%) Sanders type II, 13 (56.52%) Sanders type III, and 8 (34.78%) Sanders type IV fractures. The mean Maryland Foot Score and American Orthopaedic Foot and Ankle Society Ankle-Hindfoot Score at 6 months were 86.7 (81 to 92) and 84.2 (75 to 93), whereas at 26 months, the scores were 87.7 (82 to 93) and 85.1 (75 to 94), respectively. No pin site infections, cases of sural nerve dysfunction, or revision/additional surgery was experienced, and 17 (86.6%) patients were able to return to their original occupation at the end of 26 months.


Assuntos
Fios Ortopédicos , Calcâneo/lesões , Calcâneo/cirurgia , Fixação Interna de Fraturas/métodos , Fraturas Intra-Articulares/cirurgia , Adolescente , Adulto , Calcâneo/diagnóstico por imagem , Redução Fechada , Feminino , Fluoroscopia , Seguimentos , Humanos , Fraturas Intra-Articulares/classificação , Fraturas Intra-Articulares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados da Assistência ao Paciente , Estudos Prospectivos , Retorno ao Trabalho , Adulto Jovem
8.
Breast Cancer Res ; 20(1): 10, 2018 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-29402289

RESUMO

BACKGROUND: High mammographic density is associated with both risk of cancers being missed at mammography, and increased risk of developing breast cancer. Stratification of breast cancer prevention and screening requires mammographic density measures predictive of cancer. This study compares five mammographic density measures to determine the association with subsequent diagnosis of breast cancer and the presence of breast cancer at screening. METHODS: Women participating in the "Predicting Risk Of Cancer At Screening" (PROCAS) study, a study of cancer risk, completed questionnaires to provide personal information to enable computation of the Tyrer-Cuzick risk score. Mammographic density was assessed by visual analogue scale (VAS), thresholding (Cumulus) and fully-automated methods (Densitas, Quantra, Volpara) in contralateral breasts of 366 women with unilateral breast cancer (cases) detected at screening on entry to the study (Cumulus 311/366) and in 338 women with cancer detected subsequently. Three controls per case were matched using age, body mass index category, hormone replacement therapy use and menopausal status. Odds ratios (OR) between the highest and lowest quintile, based on the density distribution in controls, for each density measure were estimated by conditional logistic regression, adjusting for classic risk factors. RESULTS: The strongest predictor of screen-detected cancer at study entry was VAS, OR 4.37 (95% CI 2.72-7.03) in the highest vs lowest quintile of percent density after adjustment for classical risk factors. Volpara, Densitas and Cumulus gave ORs for the highest vs lowest quintile of 2.42 (95% CI 1.56-3.78), 2.17 (95% CI 1.41-3.33) and 2.12 (95% CI 1.30-3.45), respectively. Quantra was not significantly associated with breast cancer (OR 1.02, 95% CI 0.67-1.54). Similar results were found for subsequent cancers, with ORs of 4.48 (95% CI 2.79-7.18), 2.87 (95% CI 1.77-4.64) and 2.34 (95% CI 1.50-3.68) in highest vs lowest quintiles of VAS, Volpara and Densitas, respectively. Quantra gave an OR in the highest vs lowest quintile of 1.32 (95% CI 0.85-2.05). CONCLUSIONS: Visual density assessment demonstrated a strong relationship with cancer, despite known inter-observer variability; however, it is impractical for population-based screening. Percentage density measured by Volpara and Densitas also had a strong association with breast cancer risk, amongst the automated measures evaluated, providing practical automated methods for risk stratification.


Assuntos
Densidade da Mama , Neoplasias da Mama/diagnóstico , Mama/diagnóstico por imagem , Detecção Precoce de Câncer , Adulto , Idoso , Índice de Massa Corporal , Mama/patologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Feminino , Terapia de Reposição Hormonal , Humanos , Modelos Logísticos , Mamografia/classificação , Pessoa de Meia-Idade , Fatores de Risco
9.
Inorg Chem ; 57(24): 15044-15047, 2018 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-30511846

RESUMO

Herein, we have synthesized at room-temperature two-dimensional nanosheets of a MOF comprised of cobalt(II) ion with benzenedicarboxylic acid  ligand, which exhibited unusual magnetic properties. Direct-current magnetic susceptibility revealed an antiferromagnetic (AFM) transition at 26 K (Néel temperature,  TN) followed by a canting of the spin moments along with the concomitant appearance of a sigmoidal-shaped magnetization versus field ( M- H) curve at 15 K. Such a canted AFM ordering led to nonzero remnant magnetization with a remarkably high coercive field of ∼10 kOe at 5 K. Metamagnetism was further substantiated by the alternating-current magnetic susceptibility measurements.

10.
BMC Public Health ; 18(1): 178, 2018 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-29370783

RESUMO

BACKGROUND: The differences between breast cancer risk factors in white British/Irish and Asian women attending screening in the UK are not well documented. METHODS: Between 2009-15 ethnicity and traditional breast cancer risk factors were self-identified by a screening cohort from Greater Manchester, with follow up to 2016. Risk factors and incidence rates were compared using age-standardised statistics (European standard population). RESULTS: Eight hundred and seventy-nine Asian women and 51,779 unaffected white British/Irish women aged 46-73 years were recruited. Asian women were at lower predicted breast cancer risk from hormonal and reproductive risk factors than white British/Irish women (mean 10 year risk 2.6% vs 3.1%, difference 0.4%, 95%CI 0.3-0.5%). White British/Irish women were more likely to have had a younger age at menarche, be overweight or obese, taller, used hormone replacement therapy and not to have had children.. However, despite being less overweight Asian women had gained more weight from age 20 years and were less likely to undertake moderate physical activity. Asian women also had a slightly higher mammographic density. Asian age-standardised incidence was 3.2 (95%CI 1.6-5.2, 18 cancers) per thousand women/year vs 4.5 (95%CI 4.2-4.8, 1076 cancers) for white British/Irish women. CONCLUSIONS: Asian women attending screening in Greater Manchester are likely to have a lower risk of breast cancer than white British/Irish women, but they undertake less physical activity and have more adult weight gain.


Assuntos
Povo Asiático/estatística & dados numéricos , Neoplasias da Mama/etnologia , Detecção Precoce de Câncer/estatística & dados numéricos , População Branca/estatística & dados numéricos , Idoso , Neoplasias da Mama/diagnóstico , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Reino Unido/epidemiologia
11.
Proc Natl Acad Sci U S A ; 112(28): 8555-60, 2015 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-26124106

RESUMO

Human identification by fingerprints is based on the fundamental premise that ridge patterns from distinct fingers are different (uniqueness) and a fingerprint pattern does not change over time (persistence). Although the uniqueness of fingerprints has been investigated by developing statistical models to estimate the probability of error in comparing two random samples of fingerprints, the persistence of fingerprints has remained a general belief based on only a few case studies. In this study, fingerprint match (similarity) scores are analyzed by multilevel statistical models with covariates such as time interval between two fingerprints in comparison, subject's age, and fingerprint image quality. Longitudinal fingerprint records of 15,597 subjects are sampled from an operational fingerprint database such that each individual has at least five 10-print records over a minimum time span of 5 y. In regard to the persistence of fingerprints, the longitudinal analysis on a single (right index) finger demonstrates that (i) genuine match scores tend to significantly decrease when time interval between two fingerprints in comparison increases, whereas the change in impostor match scores is negligible; and (ii) fingerprint recognition accuracy at operational settings, nevertheless, tends to be stable as the time interval increases up to 12 y, the maximum time span in the dataset. However, the uncertainty of temporal stability of fingerprint recognition accuracy becomes substantially large if either of the two fingerprints being compared is of poor quality. The conclusions drawn from 10-finger fusion analysis coincide with the conclusions from single-finger analysis.


Assuntos
Dermatoglifia , Antropologia Forense , Humanos , Estudos Longitudinais , Modelos Estatísticos , Probabilidade
12.
Carcinogenesis ; 38(1): 40-50, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27729375

RESUMO

Non-melanoma skin cancers (NMSC) are a growing problem given that solar ultraviolet B (UVB) radiation exposure is increasing most likely due to depletion of the atmospheric ozone layer and lack of adequate sun protection. Better preventive methods are urgently required to reduce UV-caused photodamage and NMSC incidence. Earlier, we have reported that silibinin treatment activates p53 and reduces photodamage and NMSC, both in vitro and in vivo; but whether silibinin exerts its protective effects primarily through p53 remains unknown. To address this question, we generated p53 heterozygous (p53+/-) and p53 knockout (p53-/-) mice on SKH-1 hairless mouse background, and assessed silibinin efficacy in both short- and long-term UVB exposure experiments. In the chronic UVB-exposed skin tumorigenesis study, compared to p53+/+ mice, p53+/- mice developed skin tumors earlier and had higher tumor number, multiplicity and volume. Silibinin topical treatment significantly reduced the tumor number, multiplicity and volume in p53+/+ mice but silibinin' protective efficacy was significantly compromised in p53+/- mice. Additionally, silibinin treatment failed to inhibit precursor skin cancer lesions in p53-/- mice but improved the survival of the mice. In short-term studies, silibinin application accelerated the removal of UVB-induced DNA damage in p53+/+ mice while its efficacy was partially compromised in p53-/- mice. Interestingly, silibinin treatment also inhibited the UVB-induced inflammatory markers in skin tissue. These results further confirmed that absence of the p53 allele predisposes mice to photodamage and photocarcinogenesis, and established that silibinin mediates its protection against UVB-induced photodamage, inflammation and photocarcinogenesis partly through p53 activation.


Assuntos
Transformação Celular Neoplásica/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Inflamação/prevenção & controle , Silimarina/farmacologia , Neoplasias Cutâneas/prevenção & controle , Proteína Supressora de Tumor p53/fisiologia , Raios Ultravioleta/efeitos adversos , Animais , Antioxidantes/farmacologia , Transformação Celular Neoplásica/patologia , Transformação Celular Neoplásica/efeitos da radiação , Dano ao DNA/efeitos da radiação , Feminino , Inflamação/etiologia , Inflamação/patologia , Masculino , Camundongos , Camundongos Pelados , Camundongos Endogâmicos C57BL , Camundongos Knockout , Silibina , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/patologia
13.
Mol Carcinog ; 56(3): 833-848, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27533043

RESUMO

Hypoxia is associated with aggressive phenotype and poor prognosis in prostate cancer (PCa) patients suggesting that PCa growth and progression could be controlled via targeting hypoxia-induced signaling and biological effects. Here, we analyzed silibinin (a natural flavonoid) efficacy to target cell growth, angiogenesis, and metabolic changes in human PCa, LNCaP, and 22Rv1 cells under hypoxic condition. Silibinin treatment inhibited the proliferation, clonogenicity, and endothelial cells tube formation by hypoxic (1% O2 ) PCa cells. Interestingly, hypoxia promoted a lipogenic phenotype in PCa cells via activating acetyl-Co A carboxylase (ACC) and fatty acid synthase (FASN) that was inhibited by silibinin treatment. Importantly, silibinin treatment strongly decreased hypoxia-induced HIF-1α expression in PCa cells together with a strong reduction in hypoxia-induced NADPH oxidase (NOX) activity. HIF-1α overexpression in LNCaP cells significantly increased the lipid accumulation and NOX activity; however, silibinin treatment reduced HIF-1α expression, lipid levels, clonogenicity, and NOX activity even in HIF-1α overexpressing LNCaP cells. In vivo, silibinin feeding (200 mg/kg body weight) to male nude mice with 22Rv1 tumors, specifically inhibited tumor vascularity (measured by dynamic contrast-enhanced MRI) resulting in tumor growth inhibition without directly inducing necrosis (as revealed by diffusion-weighted MRI). Silibinin feeding did not significantly affect tumor glucose uptake measured by FDG-PET; however, reduced the lipid synthesis measured by quantitative 1 H-NMR metabolomics. IHC analyses of tumor tissues confirmed that silibinin feeding decreased proliferation and angiogenesis as well as reduced HIF-1α, FASN, and ACC levels. Together, these findings further support silibinin usefulness against PCa through inhibiting hypoxia-induced signaling. © 2016 Wiley Periodicals, Inc.


Assuntos
Antineoplásicos/administração & dosagem , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Lipogênese/efeitos dos fármacos , Metabolômica/métodos , Neovascularização Patológica/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Silimarina/administração & dosagem , Animais , Antineoplásicos/farmacologia , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Técnicas In Vitro , Masculino , Camundongos , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Transdução de Sinais/efeitos dos fármacos , Silibina , Silimarina/farmacologia , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Phys Rev Lett ; 119(6): 067201, 2017 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-28949630

RESUMO

We present and analyze Raman spectra of the Mott insulator Ca_{2}RuO_{4}, whose quasi-two-dimensional antiferromagnetic order has been described as a condensate of low-lying spin-orbit excitons with angular momentum J_{eff}=1. In the A_{g} polarization geometry, the amplitude (Higgs) mode of the spin-orbit condensate is directly probed in the scalar channel, thus avoiding infrared-singular magnon contributions. In the B_{1g} geometry, we observe a single-magnon peak as well as two-magnon and two-Higgs excitations. Model calculations using exact diagonalization quantitatively agree with the observations. Together with recent neutron scattering data, our study provides strong evidence for excitonic magnetism in Ca_{2}RuO_{4} and points out new perspectives for research on the Higgs mode in two dimensions.

15.
Carcinogenesis ; 37(6): 589-599, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27207648

RESUMO

Tumor microenvironment plays an essential role in prostate carcinogenesis and offers novel opportunities to prevent and treat prostate cancer (PCA). Here, we investigated the ability of cancer-associated fibroblasts (CAFs) to promote PCA progression, and silibinin efficacy to target this response. We collected conditioned media from CAFs treated with vehicle or silibinin, and labeled as control conditioned media (CCM) or silibinin-treatment conditioned media (SBCM), respectively. Next, we characterized the effect of CCM and SBCM treatment in several PCA cell lines (RWPE-1, WPE-1 NA-22, WPE-1 NB-14 and PC3). Result showed that compared with SBCM, CCM significantly reduces E-cadherin expression and increases invasiveness and clonogenicity in PCA cells. Further molecular studies identified monocyte chemotactic protein-1 (MCP-1) as the key component of CCM that promotes PCA invasiveness, whereas silibinin treatment strongly reduced MCP-1 expression in CAFs by inhibiting the DNA-binding activity of MCP-1 transcriptional regulators-nuclear factor-kappaB and AP-1. In vivo, silibinin feeding (200mg/kg body weight) strongly reduced TRAMPC1 allografts growth (by 68%) in syngeneic C57Bl/6 mice. TRAMPC1 tumor analysis showed that silibinin reduced MCP-1 and CAFs' biomarkers (fibroblast activation protein, α-smooth muscle actin, transforming growth factor beta 2, vimentin etc.) and significantly modulated the recruitment of immune cells in the tumor microenvironment. Similar inhibitory effects of silibinin on MCP-1 and immune cells recruitment were also observed in TRAMP PCA tissues with reported silibinin efficacy. Overall, our data suggest that silibinin can target CAF-mediated invasiveness in PCA by inhibiting MCP-1 secretion. This, in turn, was associated with a reduction in immune cell recruitment in vivo along with a marked reduction in tumor growth.


Assuntos
Quimiocina CCL2/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Silimarina/farmacologia , Microambiente Tumoral/efeitos dos fármacos , Animais , Antígenos CD , Antineoplásicos Fitogênicos/farmacologia , Caderinas/metabolismo , Linhagem Celular Tumoral , Quimiocina CCL2/genética , Meios de Cultivo Condicionados/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Humanos , Masculino , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Neoplasias da Próstata/imunologia , Silibina , Fator de Transcrição AP-1/metabolismo , Microambiente Tumoral/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
16.
N Engl J Med ; 368(13): 1179-88, 2013 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-23477676

RESUMO

BACKGROUND: Previously, we reported that there was no significant difference at 30 days in the rate of a primary composite outcome of death, myocardial infarction, stroke, or new renal failure requiring dialysis between patients who underwent coronary-artery bypass grafting (CABG) performed with a beating-heart technique (off-pump) and those who underwent CABG performed with cardiopulmonary bypass (on-pump). We now report results on quality of life and cognitive function and on clinical outcomes at 1 year. METHODS: We enrolled 4752 patients with coronary artery disease who were scheduled to undergo CABG and randomly assigned them to undergo the procedure off-pump or on-pump. Patients were enrolled at 79 centers in 19 countries. We assessed quality of life and cognitive function at discharge, at 30 days, and at 1 year and clinical outcomes at 1 year. RESULTS: At 1 year, there was no significant difference in the rate of the primary composite outcome between off-pump and on-pump CABG (12.1% and 13.3%, respectively; hazard ratio with off-pump CABG, 0.91; 95% confidence interval [CI], 0.77 to 1.07; P=0.24). The rate of the primary outcome was also similar in the two groups in the period between 31 days and 1 year (hazard ratio, 0.79; 95% CI, 0.55 to 1.13; P=0.19). The rate of repeat coronary revascularization at 1 year was 1.4% in the off-pump group and 0.8% in the on-pump group (hazard ratio, 1.66; 95% CI, 0.95 to 2.89; P=0.07). There were no significant differences between the two groups at 1 year in measures of quality of life or neurocognitive function. CONCLUSIONS: At 1 year after CABG, there was no significant difference between off-pump and on-pump CABG with respect to the primary composite outcome, the rate of repeat coronary revascularization, quality of life, or neurocognitive function. (Funded by the Canadian Institutes of Health Research; CORONARY ClinicalTrials.gov number, NCT00463294.).


Assuntos
Ponte de Artéria Coronária sem Circulação Extracorpórea , Ponte de Artéria Coronária/métodos , Doença da Artéria Coronariana/cirurgia , Idoso , Doença da Artéria Coronariana/mortalidade , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Infarto do Miocárdio/etiologia , Complicações Pós-Operatórias , Modelos de Riscos Proporcionais , Qualidade de Vida , Insuficiência Renal/etiologia , Reoperação/estatística & dados numéricos , Acidente Vascular Cerebral/etiologia
17.
Chin J Traumatol ; 19(4): 229-30, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27578381

RESUMO

The outward angulation of elbow with supinated forearm is cubitus varus deformity. This deformity is often seen as sequelae of malunited supracondylar fracture of humerus in paediatric age group of 5e8 years. The deformity is usually non-progressive, but in cases of physeal injury or congenital bony bar formation in the medial condyle of humerus, the deformity is progressive and can be grotesque in appearance. Various types of osteotomies are defined for standard non-progressive cubitus varus deformity, while multiple surgeries are required for progressive deformity until skeletal maturity. In this study we described a novel surgical approach and osteotomy of distal humerus in a 5 years old boy having grotesque progressive cubitus varus deformity, achieving good surgical outcome.


Assuntos
Lesões no Cotovelo , Fraturas Mal-Unidas/complicações , Fraturas do Úmero/complicações , Úmero/cirurgia , Deformidades Articulares Adquiridas/cirurgia , Osteotomia/métodos , Pré-Escolar , Humanos , Imageamento por Ressonância Magnética , Masculino
18.
Breast Cancer Res ; 17(1): 147, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26627479

RESUMO

INTRODUCTION: The Predicting Risk of Cancer at Screening study in Manchester, UK, is a prospective study of breast cancer risk estimation. It was designed to assess whether mammographic density may help in refinement of breast cancer risk estimation using either the Gail model (Breast Cancer Risk Assessment Tool) or the Tyrer-Cuzick model (International Breast Intervention Study model). METHODS: Mammographic density was measured at entry as a percentage visual assessment, adjusted for age and body mass index. Tyrer-Cuzick and Gail 10-year risks were based on a questionnaire completed contemporaneously. Breast cancers were identified at the entry screen or shortly thereafter. The contribution of density to risk models was assessed using odds ratios (ORs) with profile likelihood confidence intervals (CIs) and area under the receiver operating characteristic curve (AUC). The calibration of predicted ORs was estimated as a percentage [(observed vs expected (O/E)] from logistic regression. RESULTS: The analysis included 50,628 women aged 47-73 years who were recruited between October 2009 and September 2013. Of these, 697 had breast cancer diagnosed after enrolment. Median follow-up was 3.2 years. Breast density [interquartile range odds ratio (IQR-OR) 1.48, 95 % CI 1.34-1.63, AUC 0.59] was a slightly stronger univariate risk factor than the Tyrer-Cuzick model [IQR-OR 1.36 (95 % CI 1.25-1.48), O/E 60 % (95 % CI 44-74), AUC 0.57] or the Gail model [IQR-OR 1.22 (95 % CI 1.12-1.33), O/E 46 % (95 % CI 26-65 %), AUC 0.55]. It continued to add information after allowing for Tyrer-Cuzick [IQR-OR 1.47 (95 % CI 1.33-1.62), combined AUC 0.61] or Gail [IQR-OR 1.45 (95 % CI 1.32-1.60), combined AUC 0.59]. CONCLUSIONS: Breast density may be usefully combined with the Tyrer-Cuzick model or the Gail model.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Glândulas Mamárias Humanas/anormalidades , Idoso , Densidade da Mama , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Melhoria de Qualidade , Curva ROC , Radiografia , Reprodutibilidade dos Testes , Medição de Risco , Reino Unido
19.
N Engl J Med ; 366(16): 1489-97, 2012 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-22449296

RESUMO

BACKGROUND: The relative benefits and risks of performing coronary-artery bypass grafting (CABG) with a beating-heart technique (off-pump CABG), as compared with cardiopulmonary bypass (on-pump CABG), are not clearly established. METHODS: At 79 centers in 19 countries, we randomly assigned 4752 patients in whom CABG was planned to undergo the procedure off-pump or on-pump. The first coprimary outcome was a composite of death, nonfatal stroke, nonfatal myocardial infarction, or new renal failure requiring dialysis at 30 days after randomization. RESULTS: There was no significant difference in the rate of the primary composite outcome between off-pump and on-pump CABG (9.8% vs. 10.3%; hazard ratio for the off-pump group, 0.95; 95% confidence interval [CI], 0.79 to 1.14; P=0.59) or in any of its individual components. The use of off-pump CABG, as compared with on-pump CABG, significantly reduced the rates of blood-product transfusion (50.7% vs. 63.3%; relative risk, 0.80; 95% CI, 0.75 to 0.85; P<0.001), reoperation for perioperative bleeding (1.4% vs. 2.4%; relative risk, 0.61; 95% CI, 0.40 to 0.93; P=0.02), acute kidney injury (28.0% vs. 32.1%; relative risk, 0.87; 95% CI, 0.80 to 0.96; P=0.01), and respiratory complications (5.9% vs. 7.5%; relative risk, 0.79; 95% CI, 0.63 to 0.98; P=0.03) but increased the rate of early repeat revascularizations (0.7% vs. 0.2%; hazard ratio, 4.01; 95% CI, 1.34 to 12.0; P=0.01). CONCLUSIONS: There was no significant difference between off-pump and on-pump CABG with respect to the 30-day rate of death, myocardial infarction, stroke, or renal failure requiring dialysis. The use of off-pump CABG resulted in reduced rates of transfusion, reoperation for perioperative bleeding, respiratory complications, and acute kidney injury but also resulted in an increased risk of early revascularization. (Funded by the Canadian Institutes of Health Research; CORONARY ClinicalTrials.gov number, NCT00463294.).


Assuntos
Ponte de Artéria Coronária sem Circulação Extracorpórea , Ponte de Artéria Coronária , Doença da Artéria Coronariana/cirurgia , Idoso , Transfusão de Sangue/estatística & dados numéricos , Doença da Artéria Coronariana/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Insuficiência Renal/epidemiologia , Reoperação/estatística & dados numéricos , Método Simples-Cego , Acidente Vascular Cerebral/epidemiologia , Resultado do Tratamento
20.
Mol Carcinog ; 54(11): 1417-29, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25252179

RESUMO

Glioblastoma multiforme (GBM) is an untreatable malignancy. Existing therapeutic options are insufficient, and adversely affect functional and non-cancerous cells in the brain impairing different functions of the body. Therefore, there is an urgent need for additional preventive and therapeutic non-toxic drugs against GBM. Asiatic acid (AsA; 2,3,23-trihydroxy-12-ursen-28-oic acid, C30 H48 O5 ) is a natural small molecule widely used to treat various neurological disorders, and the present research investigates AsA's efficacy against GBM both in vitro and in vivo. Results showed that AsA treatment (10-100 µM) decreased the human GBM cell (LN18, U87MG, and U118MG) viability, with better efficacy than temozolomide at equimolar doses. Orally administered AsA (30 mg/kg/d) strongly decreased tumor volume in mice when administered immediately after ectopic U87MG xenograft implantation (54% decrease, P ≤ 0.05) or in mice with established xenografts (48% decrease, P ≤ 0.05) without any apparent toxicity. Importantly, AsA feeding (30 mg/kg/twice a day) also decreased the orthotopic U87MG xenografts growth in nude mice as measured by magnetic resonance imaging. Using LC/MS-MS methods, AsA was detected in mice plasma and brain tissue, confirming that AsA crosses blood-brain barrier. Mechanistic studies showed that AsA induces apoptotic death by modulating the protein expression of several apoptosis regulators (caspases, Bcl2 family members, and survivin) in GBM cells. Furthermore, AsA induced ER stress (increased GRP78 and Calpain, and decreased Calnexin and IRE1α expression), enhanced free intra-cellular calcium, and damaged cellular organization in GBM cells. These experimental results demonstrate that AsA is effective against GBM, and advocate further pre-clinical and clinical evaluations of AsA against GBM.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Triterpenos Pentacíclicos/farmacologia , Animais , Proteínas Reguladoras de Apoptose/genética , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Dacarbazina/análogos & derivados , Dacarbazina/farmacologia , Chaperona BiP do Retículo Endoplasmático , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/metabolismo , Humanos , Masculino , Camundongos , Camundongos Nus , Temozolomida , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
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