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1.
J Clin Gastroenterol ; 57(4): 325-334, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36753461

RESUMO

BACKGROUND AIMS: Preventative care plays an important role in maintaining health in patients with inflammatory bowel disease (IBD). We aimed to assess the overall quality, strength, and transparency of conflicts among guidelines on preventative care in IBD. METHODS: A systematic literature search was performed in multiple databases to identify all guidelines pertaining to preventative care in IBD in April 2021. All guidelines were reviewed for the transparency of conflicts of interest and funding, recommendation quality and strength, external guideline review, patient voice inclusion, and plan for update-as per Institute of Medicine standards. In addition, recommendations and their quality were compared between societies. RESULTS: Fifteen distinct societies and a total of 89 recommendations were included. Not all guidelines provided recommendations on the key aspects of preventative care in IBD-such as vaccinations, cancer prevention, stress reduction, and diet/exercise. Sixty-seven percent of guidelines reported on conflicts of interest, 20% underwent external review, and 27% included patient representation. In all, 6.7%, 21.3%, and 71.9% of recommendations were based on high, moderate, and low-quality evidence, respectively. Twenty-seven percent, 23.6%, and 49.4% of recommendations were strong, weak/conditional, and did not provide a strength, respectively. The proportion of high-quality evidence ( P =0.28) and strong recommendations ( P =0.41) did not significantly differ across societies. CONCLUSIONS: Many guidelines do not provide recommendations on key aspects of preventative care in IBD. As over 70% of recommendations are based on low-quality evidence, further studies on preventative care in IBD are warranted to improve the overall quality of evidence.


Assuntos
Doenças Inflamatórias Intestinais , Humanos , Doenças Inflamatórias Intestinais/terapia , Exercício Físico
2.
J Cardiothorac Vasc Anesth ; 37(9): 1677-1682, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37330331

RESUMO

OBJECTIVE: The primary aim of the authors' study was to evaluate the capacity of the portal vein pulsatility index (PVP) to detect fluid unresponsiveness in patients admitted to intensive care. DESIGN: This was a retrospective, diagnostic accuracy study SETTING: At a tertiary medical-surgical intensive care unit in Buenos Aires, Argentina. PARTICIPANTS: Patients were included during usual care in the intensive care unit, who were evaluated by ultrasonography for the flow of the portal vein, calculating their PVP prior to fluid expansion. INTERVENTIONS: Patients who exhibited an increase of <15% in left ventricle outflow tract velocity-time integral after receiving 500 mL of Ringer Lactate were considered non-responders to fluids. MEASUREMENTS AND MAIN RESULTS: The authors included a total of 63 patients between January 2022 and October 2022. The area under the receiver operating characteristic curve for PVP to predict fluid unresponsiveness was 0.708 (95% CI 0.580 to 0.816). A value of the PVP >32% predicted fluid unresponsiveness with a sensitivity of 30.8% (95% CI 17% to 47.6%) and specificity of 100% (95% CI 85.8 to 100). The positive predictive value was 100%, and the negative predictive value was 47.1% (95% CI 41.9% to 52.3%). CONCLUSIONS: Although PVP has limited value as the sole indicator for fluid management decisions, it can be used as a stopping rule or combined with other diagnostic tests to improve the accuracy of fluid responsiveness assessment.


Assuntos
Unidades de Terapia Intensiva , Veia Porta , Humanos , Veia Porta/diagnóstico por imagem , Estudos Retrospectivos , Valor Preditivo dos Testes , Curva ROC , Hidratação
3.
Gerodontology ; 40(4): 518-522, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37971285

RESUMO

BACKGROUND: Psoriasis is a common cutaneous disease; however, information about psoriasis-related oral mucosal lesions is scarce in the literature. CASE DESCRIPTION: We report a case of a 73-year-old male patient with cutaneous and oral palatal alterations. An incisional biopsy of these lesions revealed psoriasis. CONCLUSION: The current case highlights the importance of a systematic examination of the oral cavity in psoriasis patients for the appropriate diagnosis and management on the control of these lesions.


Assuntos
Mucosa Bucal , Psoríase , Masculino , Humanos , Idoso , Mucosa Bucal/patologia , Psoríase/complicações , Psoríase/diagnóstico , Psoríase/patologia , Diagnóstico Diferencial , Biópsia
4.
FEMS Yeast Res ; 21(1)2022 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-36047961

RESUMO

ERG6 gene encodes C-24 methyltransferase, one of the specific enzymes that differ in mammalian and yeast sterol biosynthesis. To explore the function of CgErg6p in the yeast pathogen Candida glabrata, we have constructed the Cgerg6Δ deletion mutant. We found that C. glabrata cells lacking CgErg6p exhibit reduced susceptibility to both antifungal azoles and polyenes. The reduced content of ergosterol in the Cgerg6 deletion mutant was accompanied by increased expression of genes encoding the last steps of the ergosterol biosynthetic pathway. The absence of CgErg6p leads to plasma membrane hyperpolarization and decrease in its fluidity compared to the parental C. glabrata strain. The absence of sterols containing C-24 alkyls influenced the susceptibility of Cgerg6Δ mutant cells to alkali metal cations and several other metabolic inhibitors. Our results thus show that sterols lacking C-24 alkyls are not sufficient substitutes for maintaining yeast plasma membrane function. The absence of CgErg6p influences also the cell wall integrity and calcineurin signaling in C. glabrata.


Assuntos
Antifúngicos , Candida glabrata , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Azóis/farmacologia , Calcineurina/metabolismo , Candida glabrata/genética , Candida glabrata/metabolismo , Membrana Celular/metabolismo , Parede Celular/metabolismo , Farmacorresistência Fúngica/genética , Ergosterol , Metiltransferases/genética , Metiltransferases/metabolismo , Testes de Sensibilidade Microbiana , Polienos/metabolismo , Polienos/farmacologia , Esteróis/metabolismo
5.
Pediatr Dermatol ; 38(5): 1247-1250, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34409648

RESUMO

Generalized verrucosis is a clinical manifestation of human papillomavirus infection. Patients with generalized verrucosis present with over 20 verrucae distributed over various anatomical sites. The disorder occurs in association with several genetic syndromes with immunodeficiency, including GATA2 deficiency. We report a 12-year-old boy with GATA2 deficiency and generalized verrucosis that worsened after cyclosporine use following bone marrow transplant. Systemic treatment with acitretin and topical application of trichloroacetic acid, likely along with immune reconstitution, led to complete remission.


Assuntos
Deficiência de GATA2 , Verrugas , Acitretina/uso terapêutico , Criança , Fator de Transcrição GATA2 , Humanos , Masculino , Papillomaviridae , Ácido Tricloroacético , Verrugas/tratamento farmacológico
6.
Cell Physiol Biochem ; 54(5): 994-1012, 2020 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-33006449

RESUMO

BACKGROUND/AIMS: Down syndrome associated disorders are caused by a complex genetic context where trisomy 21 is a central component in relation to other changes involving epigenetic regulators and signaling molecules. This unique genetic context is responsible for the predisposition of people with Down syndrome to acute leukemia. Although, the research in this field has discovered some important pathogenic keys, the exact mechanism of this predisposition is not known. METHODS: In this study we applied functional enrichment analysis to evaluate the interactions between genes localized on chromosome 21, genes already identify as having a key role in acute leukemia of Down syndrome, miRNAs and signaling pathways implicated in cancer and cell development and found that miR-155 has a high impact in genes present on chromosome 21. Forward, we performed next generation sequencing on DNA samples from a cohort of patients diagnosed with acute leukemia of Down syndrome and in vitro functional assay using a CMK-86 cell line, transfected with either mimic or inhibitor of the microRNA-155-5p. RESULTS: Our results show that the epigenetic alteration of the TNF superfamily receptors in Down syndrome, which can be correlated to microRNA-155-5p aberrant activity, may play an important role in cell signaling and thus be linked to acute myeloid leukemia. CONCLUSION: Some genes, already shown to be mutated in AML-DS, are potential targets for miR-155. Our results show that the epigenetic alteration of the TNF superfamily receptors in Down syndrome may play an important role in cell signaling and thus be linked to acute myeloid leukemia.


Assuntos
Síndrome de Down/complicações , Epigênese Genética , Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda/patologia , Reação Leucemoide/patologia , MicroRNAs/genética , Receptores do Fator de Necrose Tumoral/genética , Diferenciação Celular , Estudos de Coortes , Síndrome de Down/etiologia , Síndrome de Down/genética , Síndrome de Down/metabolismo , Síndrome de Down/patologia , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Leucemia Mieloide Aguda/etiologia , Leucemia Mieloide Aguda/metabolismo , Reação Leucemoide/etiologia , Reação Leucemoide/metabolismo , Masculino , Receptores do Fator de Necrose Tumoral/metabolismo
7.
Breast Cancer Res ; 20(1): 60, 2018 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-29921289

RESUMO

BACKGROUND: Endocrine resistance in estrogen receptor-positive (ER+) breast cancer is a major clinical problem and is associated with accelerated cancer cell growth, increased motility and acquisition of mesenchymal characteristics. However, the specific molecules and pathways involved in these altered features remain to be detailed, and may be promising therapeutic targets to overcome endocrine resistance. METHODS: In the present study, we evaluated altered expression of epithelial-mesenchymal transition (EMT) regulators in ER+ breast cancer cell models of tamoxifen or fulvestrant resistance, by gene expression profiling. We investigated the specific role of increased SNAI2 expression in fulvestrant-resistant cells by gene knockdown and treatment with a SNAIL-p53 binding inhibitor, and evaluated the effect on cell growth, migration and expression of EMT markers. Furthermore, we evaluated SNAI2 expression by immunohistochemical analysis in metastatic samples from two cohorts of patients with breast cancer treated with endocrine therapy in the advanced setting. RESULTS: SNAI2 was found to be significantly upregulated in all endocrine-resistant cells compared to parental cell lines, while no changes were observed in the expression of other EMT-associated transcription factors. SNAI2 knockdown with specific small interfering RNA (siRNA) converted the mesenchymal-like fulvestrant-resistant cells into an epithelial-like phenotype and reduced cell motility. Furthermore, inhibition of SNAI2 with specific siRNA or a SNAIL-p53 binding inhibitor reduced growth of cells resistant to fulvestrant treatment. Clinical evaluation of SNAI2 expression in two independent cohorts of patients with ER+ metastatic breast cancer treated with endocrine therapy in the advanced setting (N = 86 and N = 67) showed that high SNAI2 expression in the metastasis correlated significantly with shorter progression-free survival on endocrine treatment (p = 0.0003 and p = 0.004). CONCLUSIONS: Our results suggest that SNAI2 is a key regulator of the aggressive phenotype observed in endocrine-resistant breast cancer cells, an independent prognostic biomarker in ER+ advanced breast cancer treated with endocrine therapy, and may be a promising therapeutic target in combination with endocrine therapies in ER+ metastatic breast cancer exhibiting high SNAI2 levels.


Assuntos
Antineoplásicos Hormonais/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Fatores de Transcrição da Família Snail/genética , Adulto , Idoso , Antineoplásicos Hormonais/efeitos adversos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Receptor alfa de Estrogênio/genética , Feminino , Fulvestranto/administração & dosagem , Fulvestranto/efeitos adversos , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Células MCF-7 , Pessoa de Meia-Idade , Metástase Neoplásica
8.
Biochem Biophys Res Commun ; 498(2): 305-312, 2018 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-28911864

RESUMO

Sensor histidine kinases (SHKs) are an integral component of the molecular machinery that permits bacteria to adapt to widely changing environmental conditions. CpxA, an extensively studied SHK, is a multidomain homodimeric protein with each subunit consisting of a periplasmic sensor domain, a transmembrane domain, a signal-transducing HAMP domain, a dimerization and histidine phospho-acceptor sub-domain (DHp) and a catalytic and ATP-binding subdomain (CA). The key activation event involves the rearrangement of the HAMP-DHp helical core and translation of the CA towards the acceptor histidine, which presumably results in an autokinase-competent complex. In the present work we integrate coarse-grained, all-atom, and hybrid QM-MM computer simulations to probe the large-scale conformational reorganization that takes place from the inactive to the autokinase-competent state (conformational step), and evaluate its relation to the autokinase reaction itself (chemical step). Our results highlight a tight coupling between conformational and chemical steps, underscoring the advantage of CA walking along the DHp core, to favor a reactive tautomeric state of the phospho-acceptor histidine. The results not only represent an example of multiscale modelling, but also show how protein dynamics can promote catalysis.


Assuntos
Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Simulação de Dinâmica Molecular , Proteínas Quinases/química , Proteínas Quinases/metabolismo , Trifosfato de Adenosina/metabolismo , Histidina/metabolismo , Concentração de Íons de Hidrogênio , Fosforilação , Conformação Proteica , Domínios Proteicos
9.
Environ Monit Assess ; 190(2): 79, 2018 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-29330590

RESUMO

Global agricultural intensification has led to increased pesticide use (37-fold from 1960 to 2005) and soil erosion (14% since 2000). Conservation tillage, including no-till (NT), has been proposed as an alternative to conventional plow till (PT) to mitigate soil erosion, but past studies have reported mixed results on the effect of conservation tillage on pesticide loss. To explore the underlying factors of these differences, a meta-analysis was conducted using published data on pesticide concentration and load in agricultural runoff from NT and PT fields. Peer-reviewed articles (1985-2016) were compiled to build a database for analysis. Contrary to expectations, results showed greater concentration of atrazine, cyanazine, dicamba, and simazine in runoff from NT than PT fields. Further, we observed greater load of dicamba and metribuzin, but reduced load of alachlor from NT fields. Overall, the concentration and the load of pesticides were greater in runoff from NT fields, especially pesticides with high solubility and low affinity for solids. Thus, NT farming affects soil properties that control pesticide retention and interactions with soils, and ultimately their mobility in the environment. Future research is needed for a more complete understanding of pesticide-soil interactions in NT systems. This research could inform the selection of pesticides by farmers and improve the predictive power of pesticide transport models.


Assuntos
Agricultura/métodos , Praguicidas/análise , Poluentes do Solo/análise , Acetamidas , Atrazina/análise , Meio Ambiente , Monitoramento Ambiental , Solo/química , Triazinas
10.
Diabetes Metab Res Rev ; 33(3)2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27507764

RESUMO

CONTEXT: Metabolic syndrome (MetS) shares several similarities with hypercortisolism. OBJECTIVES: To evaluate hypothalamic-pituitary-adrenal (HPA) axis sensitivity to dexamethasone (DEX), NR3C1 single nucleotide polymorphisms (SNPs), and expression of glucocorticoid receptor (GR) isoforms and cytokines in peripheral immune cells of MetS patients and controls. DESIGN: Prospective study with 40 MetS patients and 40 controls was conducted at the Ribeirão Preto Medical School University Hospital. METHODS: Plasma and salivary cortisol were measured in basal conditions and after 0.25, 0.5, and 1 mg of DEX given at 2300 h. In addition, p.N363S (rs6195), p.ER22/23EK (rs6189-6190), and BclI (rs41423247) SNPs were evaluated by quantitative polymerase chain reaction allelic discrimination. Exons 3 to 9 and exon/intron boundaries of NR3C1 were sequenced. GR isoforms and cytokines (IL1B, IL2, IL4, IL6, IL8, IL10, IFNγ, TNFα) expression were assessed by quantitative polymerase chain reaction. RESULTS: Plasma and salivary cortisol (nmol/L) after 1-mg DEX were higher in MetS patients compared with controls (PF: 70.2 ± 17.3 vs 37.9 ± 2.6, P = .02, and SF: 4.9 ± 1.7 vs 2.2 ± 0.3, P < .0001). After all DEX doses, a lower number of MetS patients suppressed plasma and salivary cortisol compared with controls. The BclI genotypic frequencies (%) differed between patients (CC:56/CG:44) and controls (CC:50/CG:32.5/GG:17.5) (P = .03). The GRß was overexpressed (fold = 100.0; P = .002) and IL4 (fold = -265.0; P < .0001) was underexpressed in MetS. CONCLUSION: MetS patients exhibited decreased HPA sensitivity to glucocorticoid feedback. Moreover, the BclI polymorphism lower frequency, GRß overexpression, and IL4 underexpression might underlie the molecular mechanism of glucocorticoid resistance in MetS. Thus, HPA axis dysregulation might contribute to MetS pathogenesis.


Assuntos
Sistema Hipotálamo-Hipofisário/patologia , Síndrome Metabólica/fisiopatologia , Sistema Hipófise-Suprarrenal/patologia , Polimorfismo de Nucleotídeo Único/genética , Receptores de Glucocorticoides/metabolismo , Adulto , Idoso , Anti-Inflamatórios/uso terapêutico , Biomarcadores/análise , Estudos de Casos e Controles , Citocinas/metabolismo , Dexametasona/uso terapêutico , Feminino , Seguimentos , Humanos , Hidrocortisona/sangue , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Masculino , Síndrome Metabólica/tratamento farmacológico , Síndrome Metabólica/metabolismo , Pessoa de Meia-Idade , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/metabolismo , Prognóstico , Estudos Prospectivos , Isoformas de Proteínas , Receptores de Glucocorticoides/genética
11.
Environ Monit Assess ; 189(4): 162, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28293813

RESUMO

Agrochemicals can be transported from agricultural fields into streams where they might have adverse effects on water quality and ecosystems. Three enrichment experiments were conducted in a central Indiana stream to quantify pesticide and nitrogen transport dynamics. In an enrichment experiment, a compound solution is added at a constant rate into a stream to increase compound background concentration. A conservative tracer (e.g., bromide) is added to determine discharge. Water and sediment samples are taken at several locations downstream to measure uptake metrics. We assessed transport of nitrate, atrazine, metolachlor, and carbaryl through direct measurement of uptake length (S w ), uptake velocity (V f ), and areal uptake (U). S w measures the distance traveled by a nutrient along the stream reach. V f measures the velocity a nutrient moves from the water column to immobilization sites. U represents the amount of nutrient immobilized in an area of streambed per unit of time. S w varied less than one order of magnitude across pesticides. The highest S w for atrazine suggests greater transport to downstream ecosystems. Across compounds, pesticide S w was longest in August relative to October and July. V f varied less than one order of magnitude across pesticides with the highest V f for metolachlor. U varied three orders of magnitude across pesticides with the highest U associate with sediment-bound carbaryl. Increasing nitrate S w suggests a lower nitrate demand of biota in this stream. Overall, pesticide transport was best predicted by compound solubility which can complement and improve models of pesticide abundance used by water quality programs and risk assessments.


Assuntos
Agricultura , Monitoramento Ambiental , Nitratos/análise , Praguicidas/análise , Rios/química , Poluentes Químicos da Água/análise , Agroquímicos , Atrazina , Ecossistema , Indiana , Nitrogênio , Qualidade da Água
12.
Biochemistry ; 55(12): 1909-17, 2016 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-26950759

RESUMO

The mitogen-activated protein kinase ERK2 is able to elicit a wide range of context-specific responses to distinct stimuli, but the mechanisms underlying this versatility remain in question. Some cellular functions of ERK2 are mediated through regulation of gene expression. In addition to phosphorylating numerous transcriptional regulators, ERK2 is known to associate with chromatin and has been shown to bind oligonucleotides directly. ERK2 is activated by the upstream kinases MEK1/2, which phosphorylate both tyrosine 185 and threonine 183. ERK2 requires phosphorylation on both sites to be fully active. Some additional ERK2 phosphorylation sites have also been reported, including threonine 188. It has been suggested that this phospho form has distinct properties. We detected some ERK2 phosphorylated on T188 in bacterial preparations of ERK2 by mass spectrometry and further demonstrate that phosphomimetic substitution of this ERK2 residue impairs its kinase activity toward well-defined substrates and also affects its DNA binding. We used electrophoretic mobility shift assays with oligonucleotides derived from the insulin gene promoter and other regions to examine effects of phosphorylation and mutations on the binding of ERK2 to DNA. We show that ERK2 can bind oligonucleotides directly. Phosphorylation and mutations alter DNA binding and support the idea that signaling functions may be influenced through an alternate phosphorylation site.


Assuntos
Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Oligonucleotídeos/genética , Oligonucleotídeos/metabolismo , Animais , Proteína Quinase 1 Ativada por Mitógeno/química , Mutação/fisiologia , Oligonucleotídeos/química , Fosforilação/fisiologia , Ligação Proteica/fisiologia , Estrutura Secundária de Proteína , Ratos
13.
Nucleic Acids Res ; 42(18): 11433-46, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25249625

RESUMO

Polycomb group (PcG) complexes regulate cellular identity through epigenetic programming of chromatin. Here, we show that SSX2, a germline-specific protein ectopically expressed in melanoma and other types of human cancers, is a chromatin-associated protein that antagonizes BMI1 and EZH2 PcG body formation and derepresses PcG target genes. SSX2 further negatively regulates the level of the PcG-associated histone mark H3K27me3 in melanoma cells, and there is a clear inverse correlation between SSX2/3 expression and H3K27me3 in spermatogenesis. However, SSX2 does not affect the overall composition and stability of PcG complexes, and there is no direct concordance between SSX2 and BMI1/H3K27me3 presence at regulated genes. This suggests that SSX2 antagonizes PcG function through an indirect mechanism, such as modulation of chromatin structure. SSX2 binds double-stranded DNA in a sequence non-specific manner in agreement with the observed widespread association with chromatin. Our results implicate SSX2 in regulation of chromatin structure and function.


Assuntos
Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/metabolismo , Proteínas do Grupo Polycomb/antagonistas & inibidores , Proteínas Repressoras/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Cromatina/metabolismo , DNA/química , DNA/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste , Histonas/metabolismo , Humanos , Melanoma/genética , Melanoma/metabolismo , Proteínas de Neoplasias/fisiologia , Complexo Repressor Polycomb 1/antagonistas & inibidores , Complexo Repressor Polycomb 1/química , Complexo Repressor Polycomb 1/metabolismo , Complexo Repressor Polycomb 2/antagonistas & inibidores , Complexo Repressor Polycomb 2/química , Complexo Repressor Polycomb 2/metabolismo , Proteínas Repressoras/fisiologia , Espermatogênese
14.
Proc Natl Acad Sci U S A ; 110(9): 3282-6, 2013 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-23401538

RESUMO

Capacitance measurements provide a powerful means of probing the density of states. The technique has proved particularly successful in studying 2D electron systems, revealing a number of interesting many-body effects. Here, we use large-area high-quality graphene capacitors to study behavior of the density of states in this material in zero and high magnetic fields. Clear renormalization of the linear spectrum due to electron-electron interactions is observed in zero field. Quantizing fields lead to splitting of the spin- and valley-degenerate Landau levels into quartets separated by interaction-enhanced energy gaps. These many-body states exhibit negative compressibility but the compressibility returns to positive in ultrahigh B. The reentrant behavior is attributed to a competition between field-enhanced interactions and nascent fractional states.

15.
Breast Cancer Res Treat ; 154(3): 483-94, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26585578

RESUMO

Aromatase inhibitors (AI), either alone or together with chemotherapy, have become the standard adjuvant treatment for postmenopausal, estrogen receptor-positive (ER+) breast cancer. Although AIs improve overall survival, resistance is still a major clinical problem, thus additional biomarkers predictive of outcome of ER+ breast cancer patients treated with AIs are needed. Global gene expression analysis was performed on ER+ primary breast cancers from patients treated with adjuvant AI monotherapy; half experienced recurrence (median follow-up 6.7 years). Gene expression alterations were validated by qRT-PCR, and functional studies evaluating the effect of siRNA-mediated gene knockdown on cell growth were performed. Twenty-six genes, including TFF3, DACH1, RGS5, and GHR, were shown to exhibit altered expression in tumors from patients with recurrence versus non-recurrent (fold change ≥1.5, p < 0.05), and the gene expression alterations were confirmed using qRT-PCR. Ten of these 26 genes could be linked in a network associated with cellular proliferation, growth, and development. TFF3, which encodes for trefoil factor 3 and is an estrogen-responsive oncogene shown to play a functional role in tamoxifen resistance and metastasis of ER+ breast cancer, was also shown to be upregulated in an AI-resistant cell line model, and reduction of TFF3 levels using TFF3-specific siRNAs decreased the growth of both the AI-resistant and -sensitive parental cell lines. Moreover, overexpression of TFF3 in parental AI-sensitive MCF-7/S0.5 cells resulted in reduced sensitivity to the AI exemestane, whereas TFF3 overexpression had no effect on growth in the absence of exemestane, indicating that TFF3 mediates growth and survival signals that abrogate the growth inhibitory effect of exemestane. We identified a panel of 26 genes exhibiting altered expression associated with disease recurrence in patients treated with adjuvant AI monotherapy, including TFF3, which was shown to exhibit a growth- and survival-promoting effect in the context of AI treatment.


Assuntos
Antineoplásicos/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Nitrilas/uso terapêutico , Triazóis/uso terapêutico , Idoso , Androstadienos/farmacologia , Antineoplásicos/farmacologia , Inibidores da Aromatase/farmacologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Quimioterapia Adjuvante , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Feminino , Humanos , Letrozol , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Peptídeos/genética , Peptídeos/metabolismo , Proteínas RGS/genética , Proteínas RGS/metabolismo , Receptores de Estrogênio/metabolismo , Estudos Retrospectivos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Resultado do Tratamento , Fator Trefoil-3
16.
Pharmacol Res ; 100: 250-4, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26305432

RESUMO

Fyn is a non-receptor tyrosine kinase that belongs to the Src family kinases (SFKs) which under normal physiological conditions is involved in signal transduction pathways in the nervous system, as well as the development and activation of T lymphocytes. In cancer, Fyn contributes to the development and progression of several cancer types through its involvement in the control of cell growth, death, morphogenic transformation and cellular motility. Enhanced expression and/or activation of Fyn is observed in various cancers, including melanoma, glioblastoma, squamous cell carcinoma, prostate and breast cancers. Recent studies have demonstrated the importance of Fyn in the resistance or susceptibility of cancer cells to some anti-cancer treatments. We have recently shown that Fyn is upregulated in tamoxifen-resistant breast cancer cell lines and demonstrated that it plays a key role in the resistance mechanism. Further, we found that the cellular localization of Fyn within cancer cells of primary ER+ breast tumor tissue may serve as a prognostic marker. Understanding the role of Fyn in initiation and progression of cancer and its contribution to resistance against anti-cancer therapeutic agents may facilitate the development and use of novel drugs targeting Fyn for better management of malignancies.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias/genética , Neoplasias/patologia , Proteínas Proto-Oncogênicas c-fyn/genética , Antineoplásicos/uso terapêutico , Humanos , Neoplasias/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
17.
Nano Lett ; 13(11): 5242-6, 2013 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-24156357

RESUMO

Graphene placed on hexagonal-boron nitride (h-BN) experiences a superlattice (Moiré) potential, which leads to a strong reconstruction of graphene's electronic spectrum with new Dirac points emerging at sub-eV energies. Here we study the effect of such superlattices on graphene's Raman spectrum. In particular, the 2D Raman peak is found to be exquisitely sensitive to the misalignment between graphene and h-BN lattices, probably due to the presence of a strain distribution with the same periodicity of the Moiré potential. This feature can be used to identify graphene superlattices with a misalignment angle smaller than 2°.

18.
Cureus ; 16(4): e57724, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38711723

RESUMO

Introduction  The purpose of this study was to determine the prevalence of ventricular tachycardia (VT) among patients admitted with takotsubo cardiomyopathy (TCM) as well as to analyze the predictors of VT and the predictors of mortality among patients admitted with TCM. Methods Data were obtained from the National Inpatient Sample (NIS) database from January 2016 to December 2019. Patients with a primary diagnosis of TCM were selected using ICD-10 code I51.81. Subsequently, the study population was divided into patients who developed VT vs. patients who did not develop this complication. We then used multivariate logistic regression to assess the predictors of VT in our patient cohort as well as the predictors of mortality among patients admitted with TCM. Results  Of 40114 patients with TCM, 1923 developed VT (4.8%) during their hospital stay. Predictors of VT include atrial fibrillation (AF) (adjusted odds ratio (aOR): 1.592; 95% confidence interval (CI): 0.00-1.424; p=0.001), congestive heart failure (aOR: 1.451; 95% CI: 1.307-1.610; p=0.001), coagulopathy (aOR: 1.436; 95% CI: 1.150-1.793; p=0.001), and patients who self-identify in the race category as Other (aOR: 1.427; 95% CI: 1.086-1.875; p=0.011). Female sex was found to be protective against VT (aOR: 0.587; 95% CI: 0.526-0.656; p=0.001). Predictors of mortality among patients admitted with TCM include, among other factors, age (aOR: 1.014; 95% CI: 1.011-1.018; p=0.001), Asian or Pacific Islander race (aOR: 1.533; 95% CI: 1.197-1.964; p=0.001), Black race (aOR: 1.242; 95% CI: 1.062-1.452; p=0.007), VT (aOR: 1.754; 95% CI: 1.505-2.045; p=0.001), and AF (aOR: 1.441; 95% CI: 1.301-1.597; p=0.001). Some comorbidities that were protective against mortality in TCM include tobacco use disorder (aOR: 0.558; 95% CI: 0.255-0.925; p=0.028) and obstructive sleep apnea (aOR: 0.803; 95% CI: 0.651-0.990; p=0.028). The female sex was found to be protective against mortality (aOR: 0.532; 95% CI: 0.480-0.590; p=0.001).  Conclusion  In a large cohort of women admitted with TCM, we found the prevalence of VT to be 4.8%. Predictors of VT included conditions such as AF and congestive heart failure. The female sex was found to be protective against VT and protective against mortality among patients admitted with TCM.

19.
Diseases ; 12(5)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38785751

RESUMO

BACKGROUND: Appendiceal neuroendocrine tumors (NETs) rank as the third most frequent neoplasm affecting the appendix, originating from enterochromaffin cells. This study aims to evaluate the influence of various prognostic factors on the mortality rates of patients diagnosed with NETs of the appendix. METHODS: Conducted retrospectively, the study involved 3346 patients, utilizing data sourced from the Surveillance, Epidemiology, and End Results (SEER) database. Our analysis centered on investigating demographic characteristics, clinical features, overall mortality (OM), and cancer-specific mortality (CSM) among the cohort. Variables showing a p-value < 0.1 in the univariate Cox regression were incorporated into the multivariate Cox regression analysis. A Hazard Ratio (HR) > 1 indicated an unfavorable prognosis. RESULTS: In the multivariate analysis, higher OM and CSM were observed in males, older age groups, tumors with distant metastasis, poorly differentiated tumors, and those who underwent chemotherapy. Non-Hispanic Black individuals showed elevated mortality rates. CONCLUSION: Delayed diagnosis may contribute to the increased mortality in this community. Improved access to healthcare and treatment is crucial for addressing these disparities. Larger prospective studies are needed to pinpoint the underlying causes of elevated mortality in non-Hispanic Black populations, and randomized controlled trials (RCTs) are warranted to evaluate therapies for advanced-stage appendix NETs.

20.
World J Clin Oncol ; 15(6): 745-754, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38946833

RESUMO

BACKGROUND: Hepatosplenic T-cell lymphoma (HSTCL) is a rare and aggressive peripheral T-cell lymphoma with historically dismal outcomes, representing less than one percent of non-Hodgkin lymphomas. Given its rarity, the true incidence of HSTCL is unknown and most data have been extrapolated through case reports. To the best of our knowledge, the largest and most up to date study addressing the epidemiology and outcomes of patients with HSTCL in the United States covered a period from 1996 to 2014, with a sample size of 122 patients. AIM: To paint the most updated epidemiological picture of HSTCL. METHODS: A total of 186 patients diagnosed with HSTCL, between 2000 and 2017, were ultimately enrolled in our study by retrieving data from the Surveillance, Epidemiology, and End Results database. We analyzed demographics, clinical characteristics, and overall mortality (OM) as well as cancer-specific mortality (CSM) of HSTCL. Variables with a P value < 0.01 in the univariate Cox regression were incorporated into the multivariate Cox model to determine the independent prognostic factors, with a hazard ratio of greater than 1 representing adverse prognostic factors. RESULTS: Male gender was the most represented. HSTCL was most common in middle-aged patients (40-59) and less common in the elderly (80+). Non-Hispanic whites (60.75%) and non-Hispanic blacks (20.97%) were the most represented racial groups. Univariate Cox proportional hazard regression analysis of factors influencing all-cause mortality showed a higher OM among non-Hispanic black patients. CSM was also higher among non-Hispanic blacks and patients with distant metastasis. Multivariate Cox proportional hazard regression analysis of factors affecting CSM revealed higher mortality in patients aged 80 or older and non-Hispanic blacks. CONCLUSION: Overall, the outlook for this rare malignancy is very grim. In this retrospective cohort study of the United States population, non-Hispanic blacks and the elderly had a higher CSM. This data highlights the need for larger prospective studies to investigate factors associated with worse prognosis in one ethnic group, such as treatment delays, which have been shown to increase mortality in this racial/ethnic group for other cancers.

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