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1.
Physiol Genomics ; 55(9): 381-391, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37458461

RESUMO

This study investigated the effects of different multiple low doses of streptozotocin (STZ), namely 35 and 55 mg/kg, on the onset and progression of diabetes in mice. Both doses are commonly used in research, and although both induced a loss of beta cell mass, they had distinct effects on whole glucose tolerance, beta cell function, and gene transcription. Mice treated with 55 mg/kg became rapidly glucose intolerant, whereas those treated with 35 mg/kg had a slower onset and remained glucose tolerant for up to a week before becoming equally glucose intolerant as the 55 mg/kg group. Beta cell mass loss was similar between the two groups, but the 35 mg/kg-treated mice had improved glucose-stimulated insulin secretion in gold-standard hyperglycemic clamp studies. Transcriptomic analysis revealed that the 55 mg/kg dose caused disruptions in nearly five times as many genes as the 35 mg/kg dose in isolated pancreatic islets. Pathways that were downregulated in both doses were more downregulated in the 55 mg/kg-treated mice, whereas pathways that were upregulated in both doses were more upregulated in the 35 mg/kg-treated mice. Moreover, we observed a differential downregulation in the 55 mg/kg-treated islets of beta cell characteristic pathways, such as exocytosis or hormone secretion. On the other hand, apoptosis was differentially upregulated in 35 mg/kg-treated islets, suggesting different transcriptional mechanisms in the onset of STZ-induced damage in the islets. This study demonstrates that the two STZ doses induce distinctly mechanistic progressions for the loss of functional beta cell mass.


Assuntos
Diabetes Mellitus Experimental , Células Secretoras de Insulina , Ilhotas Pancreáticas , Camundongos , Animais , Estreptozocina/efeitos adversos , Estreptozocina/metabolismo , Ilhotas Pancreáticas/metabolismo , Células Secretoras de Insulina/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Glucose/metabolismo , Insulina/metabolismo , Glicemia/metabolismo
2.
Int J Mol Sci ; 24(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37685947

RESUMO

Pickering emulsions (PEs) differ from conventional emulsions in the use of solid colloidal particles as stabilizing agents instead of traditional amphiphilic molecules. Nanostructured biopolymers (NBs) emerge as a promising alternative for PE stabilization owing to their remarkable biocompatibility, abundant availability, and low cost. To explore this potential, a study is herein presented, in which cellulose nanocrystals (CNCs), both type I and type II allomorphs, and chitin nanocrystals (ChNCs) were used for stabilizing oil-in-water PEs prepared by the use of ultrasound. Sunflower oil was selected as the oil phase as it offers the advantages of being edible, renewable, and inexpensive. By utilizing ζ-potential, static light diffraction, and visual observations, we determined the optimal oil/water ratio for each type of NB to obtain stable emulsions after 14 days. The optimized PEs were used to form bacterial nanocellulose composites through emulsion templating. To our knowledge, this study represents a pioneering work in exploiting oil-in-water PEs for this approach. Additionally, it entails the first utilization of nonmercerized type II CNCs as stabilizers for PEs, while also establishing a direct comparison among the most relevant NBs. The resulting composites exhibited a unique morphology, composed of larger pores compared to standard bacterial nanocellulose aerogels. These findings highlight the notable potential of NBs as stabilizers for PEs and their ability to generate green nanocomposites with tailored properties.


Assuntos
Nanocompostos , Nanopartículas , Celulose , Emulsões , Biopolímeros
3.
Int J Mol Sci ; 24(19)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37833895

RESUMO

Vitamin D is an environmental factor related to multiple sclerosis that plays a significant role in immune regulation. TGF-ß is a superfamily of cytokines with an important dual effect on the immune system. TGF-ß inhibits the Th1 response while facilitating the preservation of regulatory T cells (FOXP3+) in an immunoregulatory capacity. However, when IL-6 is present, it stimulates the Th17 response. Our aim was to analyze the regulatory effect of vitamin D on the in vivo TGF-ß signaling pathway in patients with relapsing-remitting multiple sclerosis (RRMS). A total of 21 patients with vitamin D levels < 30 ng/mL were recruited and supplemented with oral vitamin D. All patients were receiving disease-modifying therapy, with the majority being on natalizumab. Expression of SMAD7, ERK1, ZMIZ1, BMP2, BMPRII, BMP4, and BMP5 was measured in CD4+ lymphocytes isolated from peripheral blood at baseline and one and six months after supplementation. SMAD7 was overexpressed at six months with respect to baseline and month one. ERK1 was overexpressed at six months with respect to month one of treatment. No significant differences in expression were observed for the remaining genes. No direct correlation was found with serum vitamin D levels. BMPRII expression changed differentially in non-natalizumab- versus natalizumab-treated patients. Changes were observed in the expression of ERK1, BMP2, and BMP5 based on disease activity measured using the Rio-Score, BMP2 in patients who had relapses, and BMP5 in those whose EDSS worsened. Our results suggest indirect regulation of vitamin D in TGF-ß pathway genes in patients with RRMS.


Assuntos
Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Humanos , Vitamina D/metabolismo , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/genética , Natalizumab , Vitaminas/farmacologia , Vitaminas/uso terapêutico , Fator de Crescimento Transformador beta/genética
4.
Mikrochim Acta ; 189(2): 62, 2022 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-35031873

RESUMO

Two cellulose nanocrystals/single-walled carbon nanotube (CNC/SW) hybrids, using two cellulose polymorphs, were evaluated as electrochemical transducers: CNC type I (CNC-I/SW) and CNC type II (CNC-II/SW). They were synthesized and fully characterized, and their analytical performance as electrochemical sensors was carefully studied. In comparison with SWCNT-based and screen-printed carbon electrodes, CNC/SW sensors showed superior electroanalytical performance in terms of sensitivity and selectivity, not only in the detection of small metabolites (uric acid, dopamine, and tyrosine) but also in the detection of complex glycoproteins (alpha-1-acid glycoprotein (AGP)). More importantly, CNC-II/SW exhibited 20 times higher sensitivity than CNC-I/SW for AGP determination, yielding a LOD of 7 mg L-1.These results demonstrate the critical role played by nanocellulose polymorphism in the electrochemical performance of CNC/SW hybrid materials, opening new directions in the electrochemical sensing of these complex molecules. In general, these high-active-surface hybrids smartly exploited the preserved non-oxidized SW conductivity with the high aqueous dispersibility of the CNC, avoiding the use of organic solvents or the incorporation of toxic surfactants during their processing, making the CNC/SW hybrids promising nanomaterials for electrochemical detection following greener approaches.


Assuntos
Celulose/química , Técnicas Eletroquímicas/métodos , Nanotubos de Carbono/química , Estrutura Molecular , Nanocompostos/química
5.
Angew Chem Int Ed Engl ; 61(9): e202113286, 2022 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-34730273

RESUMO

Nanomaterials offer exciting properties and functionalities. However, their production and processing frequently involve complex methods, cumbersome equipment, harsh conditions, and hazardous media. The capability of organisms to accomplish this using mild conditions offers a sustainable, biocompatible, and environmentally friendly alternative. Different nanomaterials such as metal nanoparticles, quantum dots, silica nanostructures, and nanocellulose are being synthesized increasingly through living entities. In addition, the bionanofabrication potential enables also the in situ processing of nanomaterials inside biomatrices with unprecedented outcomes. In this Minireview we present a critical state-of-the-art vision of current nanofabrication approaches mediated by living entities (ranging from unicellular to higher organisms), in order to expand this knowledge and scrutinize future prospects. An efficient interfacial interaction at the nanoscale by green means is within reach through this approach.


Assuntos
Bactérias/química , Bombyx/química , Nanoestruturas/química , Animais
6.
Neurol Sci ; 41(9): 2569-2574, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32248320

RESUMO

BACKGROUND: Plasma exchange (PLEX) is a therapeutic option in the treatment of acute attacks of Demyelinating Diseases of the Central Nervous System (DDCNS). Factors related with PLEX response are not well established. METHODS: Descriptive and retrospective study. We included patients treated with PLEX for acute attacks of DDCNS between 2008 and 2017. We recorded demographics, clinical and treatment-related data, and Expanded Disability Status Scale (EDSS) score at admission, at discharge, and at 6 months. RESULTS: We included 64 patients. Forty-eight (75%) were female with a mean age of 48.28 ± 11.5 years. Half of our patients were diagnosed with multiple sclerosis. Clinical improvement was achieved in 51.6% at discharge and 62.5% at 6 months. The logistic regression model showed that EDSS score > 3 at admission (p = 0.04) and early clinical improvement with PLEX (p = 0.00) were predictors of good response to PLEX at discharge and at 6 months, respectively. No serious adverse effects were identified. CONCLUSIONS: PLEX is a safe and effective treatment for acute attacks of DDCNS. EDSS score at admission and early clinical improvement with PLEX were factors associated with good response to PLEX.


Assuntos
Esclerose Múltipla , Neuromielite Óptica , Adulto , Sistema Nervoso Central , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/terapia , Neuromielite Óptica/terapia , Troca Plasmática , Estudos Retrospectivos
7.
Int J Mol Sci ; 21(2)2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31968593

RESUMO

The Th17 immune response plays a key role in autoimmune diseases such as multiple sclerosis (MS) and inflammatory bowel disease (IBD). Expression of Th17-related genes in inflamed tissues has been reported in autoimmune diseases. However, values are frequently obtained using invasive methods. We aimed to identify biomarkers of MS in an accessible sample, such as blood, by quantifying the relative expression of 91 Th17-related genes in CD4+ T lymphocytes from patients with MS during a relapse or during a remitting phase. We also compared our findings with those of healthy controls. After confirmation in a validation cohort, expression of SMAD7 and S1PR1 mRNAs was decreased in remitting disease (-2.3-fold and -1.3-fold, respectively) and relapsing disease (-2.2-fold and -1.3-fold, respectively). No differential expression was observed for other SMAD7-related genes, namely, SMAD2, SMAD3, and SMAD4. Under-regulation of SMAD7 and S1PR1 was also observed in another autoimmune disease, Crohn's disease (CD) (-4.6-fold, -1.6-fold, respectively), suggesting the presence of common markers for autoimmune diseases. In addition, expression of TNF, SMAD2, SMAD3, and SMAD4 were also decreased in CD (-2.2-fold, -1.4-fold, -1.6-fold, and -1.6-fold, respectively). Our study suggests that expression of SMAD7 and S1PR1 mRNA in blood samples are markers for MS and CD, and TNF, SMAD2, SMAD3, and SMAD4 for CD. These genes could prove useful as markers of autoimmune diseases, thus obviating the need for invasive methods.


Assuntos
Biomarcadores/análise , Doença de Crohn/imunologia , Esclerose Múltipla/imunologia , Transdução de Sinais , Receptores de Esfingosina-1-Fosfato/genética , Linfócitos T CD4-Positivos , Humanos , Proteína Smad2/genética , Proteína Smad3/genética , Proteína Smad4/genética , Proteína Smad7/genética , Células Th17/imunologia , Fator de Crescimento Transformador beta/genética
8.
Rev Med Chil ; 148(5): 697-701, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-33399764

RESUMO

Hyperthyroidism can induce elevation in several liver function tests including aminotransferases, alkaline phosphatases and, less frequently, serum bilirubin. These alterations are usually mild and asymptomatic. We report a 26 year-old male presenting with palpitations, progressive jaundice, choluria and generalized itching. Laboratory tests were compatible with hyperthyroidism and a mild elevation of bilirubin, alkaline phosphatases and gamma glutamyl transpeptidase. A liver biopsy showed portal hepatitis with canalicular cholestasis. The patient was treated temporarily with glucocorticoids, cholestyramine and betablockade. Thereafter, he was treated with radioactive iodine, after which serum bilirubin decreased steadily until normalization in ten weeks.


Assuntos
Colestase , Doença de Graves , Hipertireoidismo , Adulto , Colestase/diagnóstico , Colestase/etiologia , Doença de Graves/complicações , Humanos , Hipertireoidismo/complicações , Masculino
9.
Mo Med ; 117(4): 383-387, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32848278

RESUMO

Malignant colon and rectal disorders must be identified and treated. Timing and indication for diagnostic and screening colonoscopy are extremely important. A high index of suspicion to exclude malignancy is imperative. This paper will focus on the screening for and treatment of colorectal and anal cancers.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/tendências , Programas de Rastreamento/métodos , Atenção Primária à Saúde/métodos , Colonoscopia/métodos , Detecção Precoce de Câncer/métodos , Detecção Precoce de Câncer/estatística & dados numéricos , Humanos , Programas de Rastreamento/estatística & dados numéricos , Programas de Rastreamento/tendências , Atenção Primária à Saúde/tendências
10.
Mo Med ; 117(2): 154-158, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32308242

RESUMO

Anorectal conditions are one of the most common problems evaluated by primary care physicians. Most patients present with rectal pain, rectal bleeding, or purulent drainage per rectum. Colorectal conditions have overlapping symptoms. Thorough history and careful anorectal examination can differentiate common anorectal conditions like hemorrhoids, anorectal abscesses, anal fistula, anal fissure, and anal condyloma. Most of these conditions can be diagnosed and treated without imaging.


Assuntos
Doenças do Ânus/diagnóstico , Cirurgia Colorretal , Fissura Anal/diagnóstico , Hemorroidas/diagnóstico , Doenças do Ânus/cirurgia , Diagnóstico Diferencial , Fissura Anal/cirurgia , Hemorroidas/cirurgia , Humanos , Atenção Primária à Saúde
11.
12.
Biomacromolecules ; 20(8): 3147-3160, 2019 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-31251612

RESUMO

Nanocellulose is increasingly being investigated as a paradigm of a sustainable nanomaterial because of its extraordinary physical and chemical properties, together with its renewable nature and worldwide abundance. The rich structural diversity of cellulose materials is represented by different crystalline allomorphs, from which types I and II stand out. While type I is naturally and ubiquitously present, type II is man-made and requires harsh and caustic synthesis conditions such as the so-called mercerization process. Here, we provide an optimal scenario to obtain either type-I or II nanocrystalline cellulose (NCC) by a mercerization-free method consisting only of the acid hydrolysis commonly used to produce nanocellulose from microcellulose. The possibility of having nonmercerized type-II NCC acquires a great relevance since this nanostructure shows particularly appealing properties. Moreover, an entangled and wrapped system arises when used as a dispersing agent for single-walled carbon nanotubes (SWCNTs), significantly different from that of type I. The biological testing of each NCC type and their respective SWCNT-NCC dispersions in human intestinal (Caco-2) cells reveals a general innocuous behavior in both cancer and normal stages of differentiation; however, the type-II-based SWCNT-NCC dispersions display cytotoxicity for cancer cells while enhancing mitochondrial metabolism of normal cells.


Assuntos
Materiais Biocompatíveis/química , Diferenciação Celular , Sobrevivência Celular , Celulose/química , Nanopartículas/química , Nanotubos de Carbono/química , Células CACO-2 , Humanos
13.
Phys Chem Chem Phys ; 21(7): 4063-4071, 2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30714592

RESUMO

The effect of doping on the electronic properties in bulk single-walled carbon nanotube (SWCNT) samples is studied for the first time using a new in situ Raman spectroelectrochemical method, and further verified by DFT calculations and photoresponse. We use p-/n-doped SWCNTs prepared by diazonium reactions as a versatile chemical strategy to control the SWCNT behavior. The measured and calculated data testify an acceptor effect of 4-aminobenzenesulfonic acid (p-doping), and a donor effect (n-doping) in the case of benzyl alcohol. In addition, pristine and covalently functionalized SWCNTs were used for the preparation of photoactive film electrodes. The photocathodic current in the photoelectrochemical cell is consistently modulated by the doping group. These results validate the in situ Raman spectroelectrochemistry as a unique tool box for predicting the electronic properties of functionalized SWCNTs in the form of thin films and their operational functionality in thin film devices for future optoelectronic applications.

14.
BMC Public Health ; 19(1): 909, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31286946

RESUMO

It has been highlighted that the original article [1] contained a mistake in the 'Results' section, specifically in the percentages of female subjects and those with diagnosis of RRMS. Please note that this mistake has only been present in the 'Results' section, the Abstract and Table 1 remain unchanged. This article shows the incorrect and correct version of the percentages.

15.
BMC Public Health ; 19(1): 609, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31109317

RESUMO

BACKGROUND: In multiple sclerosis (MS), half of affected people are unemployed within 10 years of diagnosis. The aim of this study was to assess the economic impact of MS in adult subjects with relapsing-remitting MS (RRMS) and primary progressive MS (PPMS). METHODS: A multicenter, non-interventional, cross-sectional study was conducted. The Expanded Disability Status Scale (EDSS) and the 23-item Multiple Sclerosis Work Difficulties Questionnaire (MSWDQ-23) were used to assess disability and work performance, respectively. Only indirect costs were considered using the human capital method, including work costs. Professional support costs and informal caregivers' costs were also estimated. RESULTS: A total of 199 subjects were studied (mean age: 43.9 ± 10.5 years, 60.8% female, 86.4% with RRMS). Median EDSS score was 2.0 (interquartile range: 1.0-3.5) and median MSWDQ-23 total score was 31.5 (15.2, 50.0). The number of employed subjects decreased after MS diagnosis from 70.6 to 47.2%, and the number of retired people increased (23.6%). Mean age of retirement was 43.6 ± 10.5 years. Ten percent of the population had sick leaves (absenteeism was seen in 90.9% of the student population and 30.9% of the employed population). Professional support in their daily life activities was needed in 28.1% of subjects. Costs for sick leave, work absenteeism, premature retirement and premature work disability/pensioner were €416.6 ± 2030.2, €763.4 ± 3161.8, €5810.1 ± 13,159.0 and €1816.8 ± 9630.7, respectively. Costs for professional support and informal caregiving activities were €1026.93 ± 4622.0 and €1328.72, respectively. CONCLUSIONS: MS is responsible for a substantial economic burden due to indirect and informal care costs, even in a population with low physical disability.


Assuntos
Efeitos Psicossociais da Doença , Pessoas com Deficiência/estatística & dados numéricos , Esclerose Múltipla/economia , Absenteísmo , Adulto , Estudos Transversais , Emprego/economia , Emprego/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pensões/estatística & dados numéricos , Aposentadoria/economia , Aposentadoria/estatística & dados numéricos , Licença Médica/economia , Licença Médica/estatística & dados numéricos , Espanha , Inquéritos e Questionários
16.
J Ultrasound Med ; 36(11): 2299-2307, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28543974

RESUMO

OBJECTIVES: Follow-up of patients with low-risk differentiated thyroid cancer treated with total thyroidectomy and radioiodine requires neck sonography and thyroglobulin (Tg). The need to stimulate Tg is controversial. The goal of this study was to compare the diagnostic performances of sonography plus suppressed or stimulated Tg in low-risk thyroid cancer. METHODS: After total thyroidectomy and radioiodine, patients with low-risk thyroid cancer were retrospectively identified as having structural or biochemical persistence/recurrence. We compared the diagnostic performance of suppressed and stimulated Tg to detect persistence/recurrence. RESULTS: We included 148 patients with low-risk thyroid cancer who were followed for a median of 3.7 years. Persistence/recurrence was found in 8 patients (5.4%; 5 structural disease and 3 biochemical disease). Thyroglobulin was not stimulated in 72 patients (group 1) and stimulated in 76 (group 2). In group 1, 5 patients (6.9%) had structural neck persistence/recurrence (3 with suppressed Tg ≥ 1 ng/mL and 2 with suppressed Tg < 1 ng/mL). Four patients underwent surgery, and 1 was surveilled. All 5 patients had suppressed Tg lower than 1 ng/mL at the end of follow-up. In group 2, stimulated Tg did not identify additional cases of structural persistence/recurrence but classified 3 patients (3.9%) as having biochemical persistence/recurrence. One patient received a second dose of radioiodine, and the other 2 were surveilled; all were without disease at the end of follow-up. Suppressed and stimulated Tg had negative predictive values for persistence/recurrence of 97% and 100%, respectively. CONCLUSIONS: In low-risk thyroid cancer treated with total thyroidectomy and radioiodine, sonography and suppressed or stimulated Tg have similar negative predictive values for persistence/recurrence. Importantly, the coexistence of negative sonographic findings and suppressed Tg lower than 1 ng/mL makes the addition of stimulated Tg unlikely to identify clinically important disease.


Assuntos
Radioisótopos do Iodo/uso terapêutico , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/diagnóstico por imagem , Tireoglobulina/sangue , Neoplasias da Glândula Tireoide/terapia , Ultrassonografia/métodos , Adulto , Braquiterapia/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Pescoço/diagnóstico por imagem , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/sangue , Tireoidectomia
17.
Bioprocess Biosyst Eng ; 40(7): 1123-1132, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28488139

RESUMO

Lipases are versatile catalysts with many applications and can be produced by solid-state fermentation (SSF) using agro-industrial wastes. The aim of this work was to maximize the production of Aspergillus ibericus lipase under SSF of olive pomace (OP) and wheat bran (WB), evaluating the effect on lipase production of C/N ratio, lipids, phenols, content of sugars of substrates and nitrogen source addition. Moreover, the implementation of the SSF process in a packed-bed bioreactor and the improvement of lipase extraction conditions were assessed. Low C/N ratios and high content of lipids led to maximum lipase production. Optimum SSF conditions were achieved with a C/N mass ratio of 25.2 and 10.2% (w/w) lipids in substrate, by the mixture of OP:WB (1:1) and supplemented with 1.33% (w/w) (NH4)2SO4. Studies in a packed-bed bioreactor showed that the lower aeration rates tested prevented substrate dehydration, improving lipase production. In this work, the important role of Triton X-100 on lipase extraction from the fermented solid substrate has been shown. A final lipase activity of 223 ± 5 U g-1 (dry basis) was obtained after 7 days of fermentation.


Assuntos
Fermentação , Reatores Biológicos , Microbiologia Industrial , Lipase , Olea
18.
N Engl J Med ; 368(7): 623-32, 2013 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-23406027

RESUMO

BACKGROUND: Metastatic thyroid cancers that are refractory to radioiodine (iodine-131) are associated with a poor prognosis. In mouse models of thyroid cancer, selective mitogen-activated protein kinase (MAPK) pathway antagonists increase the expression of the sodium-iodide symporter and uptake of iodine. Their effects in humans are not known. METHODS: We conducted a study to determine whether the MAPK kinase (MEK) 1 and MEK2 inhibitor selumetinib (AZD6244, ARRY-142886) could reverse refractoriness to radioiodine in patients with metastatic thyroid cancer. After stimulation with thyrotropin alfa, dosimetry with iodine-124 positron-emission tomography (PET) was performed before and 4 weeks after treatment with selumetinib (75 mg twice daily). If the second iodine-124 PET study indicated that a dose of iodine-131 of 2000 cGy or more could be delivered to the metastatic lesion or lesions, therapeutic radioiodine was administered while the patient was receiving selumetinib. RESULTS: Of 24 patients screened for the study, 20 could be evaluated. The median age was 61 years (range, 44 to 77), and 11 patients were men. Nine patients had tumors with BRAF mutations, and 5 patients had tumors with mutations of NRAS. Selumetinib increased the uptake of iodine-124 in 12 of the 20 patients (4 of 9 patients with BRAF mutations and 5 of 5 patients with NRAS mutations). Eight of these 12 patients reached the dosimetry threshold for radioiodine therapy, including all 5 patients with NRAS mutations. Of the 8 patients treated with radioiodine, 5 had confirmed partial responses and 3 had stable disease; all patients had decreases in serum thyroglobulin levels (mean reduction, 89%). No toxic effects of grade 3 or higher attributable by the investigators to selumetinib were observed. One patient received a diagnosis of myelodysplastic syndrome more than 51 weeks after radioiodine treatment, with progression to acute leukemia. CONCLUSIONS: Selumetinib produces clinically meaningful increases in iodine uptake and retention in a subgroup of patients with thyroid cancer that is refractory to radioiodine; the effectiveness may be greater in patients with RAS-mutant disease. (Funded by the American Thyroid Association and others; ClinicalTrials.gov number, NCT00970359.).


Assuntos
Benzimidazóis/uso terapêutico , Radioisótopos do Iodo/uso terapêutico , MAP Quinase Quinase 1/antagonistas & inibidores , MAP Quinase Quinase 2/antagonistas & inibidores , Neoplasias da Glândula Tireoide/radioterapia , Adulto , Idoso , Benzimidazóis/farmacologia , Feminino , Humanos , Radioisótopos do Iodo/farmacocinética , Masculino , Pessoa de Meia-Idade , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Imagem Multimodal , Mutação , Metástase Neoplásica , Tomografia por Emissão de Pósitrons , Radiometria , Simportadores/efeitos dos fármacos , Simportadores/metabolismo , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Tirotropina Alfa/farmacologia , Tomografia Computadorizada por Raios X
19.
J Biol Chem ; 289(9): 5510-7, 2014 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-24398675

RESUMO

Sterol regulatory element-binding protein-1 (SREBP-1) is a key transcription factor that regulates genes in the de novo lipogenesis and glycolysis pathways. The levels of SREBP-1 are significantly elevated in obese patients and in animal models of obesity and type 2 diabetes, and a vast number of studies have implicated this transcription factor as a contributor to hepatic lipid accumulation and insulin resistance. However, its role in regulating carbohydrate metabolism is poorly understood. Here we have addressed whether SREBP-1 is needed for regulating glucose homeostasis. Using RNAi and a new generation of adenoviral vector, we have silenced hepatic SREBP-1 in normal and obese mice. In normal animals, SREBP-1 deficiency increased Pck1 and reduced glycogen deposition during fed conditions, providing evidence that SREBP-1 is necessary to regulate carbohydrate metabolism during the fed state. Knocking SREBP-1 down in db/db mice resulted in a significant reduction in triglyceride accumulation, as anticipated. However, mice remained hyperglycemic, which was associated with up-regulation of gluconeogenesis gene expression as well as decreased glycolysis and glycogen synthesis gene expression. Furthermore, glycogen synthase activity and glycogen accumulation were significantly reduced. In conclusion, silencing both isoforms of SREBP-1 leads to significant changes in carbohydrate metabolism and does not improve insulin resistance despite reducing steatosis in an animal model of obesity and type 2 diabetes.


Assuntos
Regulação da Expressão Gênica/fisiologia , Gluconeogênese/fisiologia , Glicogênio/biossíntese , Fígado/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Animais , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Técnicas de Silenciamento de Genes , Glicogênio/genética , Masculino , Camundongos , Obesidade/genética , Obesidade/metabolismo , Obesidade/patologia , Proteína de Ligação a Elemento Regulador de Esterol 1/genética
20.
Chemistry ; 21(51): 18631-41, 2015 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-26564100

RESUMO

In the vast field of functionalization routes to carbon nanoforms, the fulfillment of such critical requirements as quick and nonharsh methods, good dispersibility, introduction of reactive groups, short reaction time, and low cost can be quite challenging. Traditional thermally induced diazonium chemistry on single-walled carbon nanotubes (SWCNTs) is revisited by using commercial anilines and providing useful insight into the versatility of this approach. Functionalized SWCNTs with multiple controllable features, such as degree (and ratio) of coverage, orthogonalization, doping, and high water dispersibility, are obtained by introducing benzenesulfonic acid and benzylamine moieties. The scenario opens up an avenue to address relevant applications in which most functionalization methods could not be applied in a straightforward way.

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