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1.
J Emerg Med ; 67(1): e80-e88, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38806349

RESUMO

BACKGROUND: Emergency physicians and trainees provide the initial care for critically ill patients. In times of emergency department boarding, this care may extend beyond the first few hours. To meet the needs of this population, a standardized novel critical care curriculum targeting third- and fourth-year medical students was developed. OBJECTIVES: We hypothesized that the institution of such a curriculum is feasible and will provide an increased understanding of the underlying critical care principles within this learner population. METHODS: We developed a 2-month-long critical care curriculum (February-April) and carried out the course twice from 2022-2023. Our pilot study deployed this curriculum to medical students interested in critical care through the American Academy of Emergency Medicine/Resident and Student Association. The primary outcome included was the overall composite score comparison of the pre- and post-course evaluations, with a higher score indicating that the student improved their comprehension. Secondary outcomes included the individual factors of the pre- and post-course surveys. RESULTS: Fifty-one trainees completed the pilot course, including 11/51 (21.6%) third-year medical students and 40/51 (78.4%) fourth-year medical students. Overall, 39 had "no experience" in critical care and 12 indicated that they had "previous experience." The students' baseline pre-course from the pooled 2022 and 2023 Introduction to Critical Care in Emergency Medicine (ICCEM) curriculum data was 3 (interquartile range 4-3) and their post-course score was 9 (interquartile range 9-9), p-value 0.015 for the 51/54 students who completed the course. CONCLUSIONS: The novel curriculum was found to be effective during its implementation in third- and fourth-year medical students. As such, it indicated that a critical care fundamentals course improves confidence in these topics for students with and without prior experience. Further work is necessary to understand the generalizability and knowledge retention of the proposed pilot curriculum.


Assuntos
Cuidados Críticos , Currículo , Medicina de Emergência , Estudantes de Medicina , Humanos , Currículo/tendências , Currículo/normas , Medicina de Emergência/educação , Cuidados Críticos/métodos , Projetos Piloto , Estudantes de Medicina/estatística & dados numéricos , Feminino , Masculino , Inquéritos e Questionários , Adulto , Educação de Graduação em Medicina/métodos , Educação de Graduação em Medicina/normas , Avaliação Educacional/métodos
2.
J Mol Evol ; 91(2): 204-213, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36651965

RESUMO

Interferon induced with helicase C domain-containing protein 1 (IFIH1) gene encodes a cytoplasmic RNA helicase otherwise known as melanoma differentiation-associated 5 (MDA5), a RIG-1-like RNA helicase that recognizes viral RNA and is involved in innate immunity through recognition of viral RNA. Upon binding to double-stranded (ds) RNA, MDA5 forms a filamentous assembly along the length of dsRNA and utilizes molecular signatures to discriminate self, versus non-self on the basis of dsRNA length and methylation. Its missense variant rs35667974 is protective for type 1 diabetes, psoriasis, and psoriatic arthritis, but is also found to be associated with an increased risk for ankylosing spondylitis, Crohn's disease, and ulcerative colitis. To gain insight into the complex role of this variant we performed a structural analysis of MDA5 in complex with dsRNA using molecular dynamics simulations. Our data suggest that while the Ile923Val mutation of the rs35667974 variant does not affect binding to native dsRNA significantly, it displays a destabilizing effect in the presence of 2'-O uridine methylation. Thus, the presence of 2'-O-methylation at the dsRNA introduces a sensing signature that leads to selective reduction of the overall MDA catalytic activity. This study represents an evaluation of the role of the shared rs35667974 variant of autoimmune locus IFIH1, reported to lead to selectively reduced catalytic activity of the modified MDA5 phenotype and, as a consequence, reduced negative feedback on cytokine and chemokine signaling and selectively protection against autoimmunity.


Assuntos
Doenças Autoimunes , RNA Helicases DEAD-box , Humanos , Helicase IFIH1 Induzida por Interferon/genética , Helicase IFIH1 Induzida por Interferon/metabolismo , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/química , RNA Helicases DEAD-box/metabolismo , Doenças Autoimunes/genética , RNA Viral/genética , RNA de Cadeia Dupla/genética , Polimorfismo Genético , Epigênese Genética/genética
3.
Scand J Clin Lab Invest ; 83(2): 69-73, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36662122

RESUMO

Methylene tetrahydrofolate reductase (MTHFR) is a key enzyme of homocysteine metabolism participating in the folate cycle. The aim of this study was to investigate the association of MTHFR C677T and MTHFR A1298C gene polymorphisms with serum folate, cobalamin (Cbl) and homocysteine (Hcy) concentrations in healthy Greek adults. The MTHFR C677T and A1298C gene polymorphisms were genotyped in 383 healthy Greek adults (199 men and 184 women) using polymerase chain reaction and reverse hybridization. Serum folate, Cbl and total Hcy (tHcy) levels were determined using immunoassays methods. Among the 383 individuals, 73 (19.1%) were normal (CC), 202 (52.7%) were heterozygous (CT) and 108 (28.2%) were homozygous (TT) regarding the MTHFR C677T gene polymorphism, while 263 (68.7%) were normal (AA), 105 (27.4%) were heterozygous (AC) and 15 (3.9%) were homozygous (CC) regarding the MTHFR A1298C gene polymorphism. The overall C and T allele frequency for the MTHFR C677T gene polymorphism was 45.4% and 54.6%, respectively, while the overall A and C allele frequency for the MTHFR A1298C gene polymorphism was 82.3% and 17.6%, respectively. The MTHFR C677T and not the A1298C gene polymorphism had a significantly influence on serum folate and tHcy levels. The individuals with 677TT genotype had significantly lower serum folate and significantly higher serum tHcy levels than individuals with 677 CC or CT genotypes. Serum folate and tHcy levels are influenced by the existence of the MTHFR C677T gene polymorphism (mainly 677TT genotype). Individuals with low serum folate levels and/or high serum tHcy levels should be further investigated for a possible existence of MTHFR C677T and not A1298C gene polymorphisms, with aim to determine the suitable treatment.


Assuntos
Ácido Fólico , Homocisteína , Metilenotetra-Hidrofolato Redutase (NADPH2) , Vitamina B 12 , Adulto , Feminino , Humanos , Masculino , Ácido Fólico/sangue , Genótipo , Grécia , Homocisteína/sangue , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo Genético , Vitamina B 12/sangue
4.
Dig Dis Sci ; 66(6): 1780-1790, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32691382

RESUMO

Budd-Chiari syndrome (BCS) is an uncommon condition, caused by obstruction to hepatic venous outflow. It is largely underdiagnosed, and a high index of suspicion is required for any patient with unexplained portal hypertension. The understanding of its etiology and pathology is improving with advances in diagnostic techniques. Recent studies reported an identifiable etiology in > 80% of cases. Myeloproliferative neoplasm (MPN) is the most common etiology, and genetic studies help in diagnosing latent MPN. Better cross-sectional imaging helps delineate the site of obstruction accurately. The majority of BCS patients are now treated by endovascular intervention and anticoagulation which have improved survival in this disease. Angioplasty of hepatic veins/inferior vena cava remains under-utilized at present. While surgical porto-systemic shunts are no longer done for BCS, liver transplantation is reserved for select indications. Some of the unresolved issues in the current management of BCS are also discussed in this review.


Assuntos
Síndrome de Budd-Chiari/diagnóstico por imagem , Síndrome de Budd-Chiari/terapia , Gerenciamento Clínico , Angioplastia/tendências , Síndrome de Budd-Chiari/fisiopatologia , Procedimentos Endovasculares/tendências , Humanos , Transplante de Fígado/tendências , Terapia Trombolítica/tendências
5.
Nucleic Acids Res ; 47(11): 5573-5586, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31169889

RESUMO

Regulation of RNA polymerase II (RNAPII)-mediated transcription controls cellular phenotypes such as cancer. Phosphatase and tensin homologue deleted on chromosome ten (PTEN), one of the most commonly altered tumor suppressors in cancer, affects transcription via its role in antagonizing the PI3K/AKT signaling pathway. Using co-immunoprecipitations and proximal ligation assays we provide evidence that PTEN interacts with AFF4, RNAPII, CDK9, cyclin T1, XPB and CDK7. Using ChIP-seq, we show that PTEN co-localizes with RNAPII and binds to chromatin in promoter and putative enhancer regions identified by histone modifications. Furthermore, we show that loss of PTEN affects RNAPII occupancy in gene bodies and further correlates with gene expression changes. Interestingly, PTEN binds to promoters and negatively regulates the expression of genes involved in transcription including AFF4 and POL2RA, which encodes a subunit of RNAPII. Loss of PTEN also increased cells' sensitivity to transcription inhibition via small molecules, which could provide a strategy to target PTEN-deficient cancers. Overall, our work describes a previously unappreciated role of nuclear PTEN, which by interacting with the transcription machinery in the context of chromatin exerts an additional layer of regulatory control on RNAPII-mediated transcription.


Assuntos
Cromatina/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , RNA Polimerase II/metabolismo , Transcrição Gênica , Animais , Linhagem Celular , Células Cultivadas , Cromatina/genética , Células HEK293 , Células HeLa , Humanos , Camundongos Endogâmicos C57BL , Camundongos Knockout , PTEN Fosfo-Hidrolase/genética , Regiões Promotoras Genéticas/genética , Ligação Proteica , RNA Polimerase II/genética , Transdução de Sinais/genética , Fatores de Elongação da Transcrição/genética , Fatores de Elongação da Transcrição/metabolismo
6.
BMC Vet Res ; 16(1): 225, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32605619

RESUMO

BACKGROUND: Retinal diseases are common in dogs. Some hereditary retinal dystrophies in dogs are important not only because they lead to vision loss but also because they show strong similarities to the orthologous human conditions. Advances in in vivo non-invasive retinal imaging allow the capture of retinal cross-section images that parallel low power microscopic examination of histological sections. Spectral domain - optical coherence tomography (SD-OCT) allows the measurement of retinal layer thicknesses and gives the opportunity for repeat examination to investigate changes in thicknesses in health (such as changes with maturation and age) and disease (following the course of retinal degenerative conditions). The purpose of this study was to use SD-OCT to measure retinal layer thicknesses in the dog during retinal maturation and over the first year of life. SD-OCT was performed on normal beagle cross dogs from 4 weeks of age to 52 weeks of age. To assess changes in layer thickness with age, measurements were taken from fixed regions in each of the 4 quadrants and the area centralis (the region important for most detailed vision). Additionally, changes in retinal layer thickness along vertical and horizontal planes passing through the optic nerve head were assessed. RESULTS: In the four quadrants an initial thinning of retinal layers occurred over the first 12 to 15 weeks of life after which there was little change in thickness. However, in the area centralis there was a thickening of the photoreceptor layer over this time period which was mostly due to a lengthening of the photoreceptor inner/outer segment layer. The retina thinned with greater distances from the optic nerve head in both vertical and horizontal planes with the dorsal retina being thicker than the ventral retina. Most of the change in thickness with distance from the optic nerve head was due to difference in thickness of the inner retinal layers. The outer retinal layers remained more constant in thickness, particularly in the horizontal plane and dorsal to the optic nerve head. CONCLUSIONS: These measurements will provide normative data for future studies.


Assuntos
Cães/anatomia & histologia , Retina/diagnóstico por imagem , Tomografia de Coerência Óptica/veterinária , Animais , Feminino , Masculino , Retina/crescimento & desenvolvimento , Tomografia de Coerência Óptica/métodos
7.
Dysphagia ; 34(6): 939-941, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31363845

RESUMO

We report a case of an uncommon type of dysphagia, due to esophagus compression by an aberrant right subclavian artery. This condition, known as dysphagia lusoria, was first recorded in 1787 by London physician David Bayford.


Assuntos
Transtornos de Deglutição/etiologia , Artéria Subclávia/anormalidades , Idoso , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/diagnóstico por imagem , Transtornos de Deglutição/patologia , Esôfago/diagnóstico por imagem , Esôfago/patologia , Feminino , Humanos , Artéria Subclávia/patologia , Tomografia Computadorizada por Raios X
8.
Biochemistry ; 57(5): 753-763, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29257674

RESUMO

The cell wall peptidoglycan is recognized as a primary target of the innate immune system, and usually its disintegration results in bacterial lysis. Bacillus cereus, a close relative of the highly virulent Bacillus anthracis, contains 10 polysaccharide deacetylases. Among these, the peptidoglycan N-acetylglucosamine deacetylase Bc1974 is the highest homologue to the Bacillus anthracis Ba1977 that is required for full virulence and is involved in resistance to the host's lysozyme. These metalloenzymes belong to the carbohydrate esterase family 4 (CE4) and are attractive targets for the development of new anti-infective agents. Herein we report the first X-ray crystal structures of the NodB domain of Bc1974, the conserved catalytic core of CE4s, in the unliganded form and in complex with four known metalloenzyme inhibitors and two amino acid hydroxamates that target the active site metal. These structures revealed the presence of two conformational states of a catalytic loop known as motif-4 (MT4), which were not observed previously for peptidoglycan deacetylases, but were recently shown in the structure of a Vibrio clolerae chitin deacetylase. By employing molecular docking of a substrate model, we describe a catalytic mechanism that probably involves initial binding of the substrate in a receptive, more open state of MT4 and optimal catalytic activity in the closed state of MT4, consistent with the previous observations. The ligand-bound structures presented here, in addition to the five Bc1974 inhibitors identified, provide a valuable basis for the design of antibacterial agents that target the peptidoglycan deacetylase Ba1977.


Assuntos
Amidoidrolases/química , Bacillus cereus/enzimologia , Proteínas de Bactérias/química , Amidoidrolases/antagonistas & inibidores , Antibacterianos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Catálise , Cristalografia por Raios X , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Ligação de Hidrogênio , Ligantes , Modelos Moleculares , Simulação de Acoplamento Molecular , Ligação Proteica , Conformação Proteica , Domínios Proteicos , Proteínas Recombinantes/química , Relação Estrutura-Atividade , Zinco/química
9.
Br J Dermatol ; 177(6): 1552-1561, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28600818

RESUMO

BACKGROUND: Phase III studies showed that some patients maintained response for ≥ 6 months following ustekinumab discontinuation. OBJECTIVES: To assess clinical responses with extended ustekinumab maintenance dosing intervals. METHODS: Adults with moderate-to-severe plaque psoriasis received ustekinumab at weeks 0, 4 and 16 during open-label treatment. Patients achieving a week-28 Physician's Global Assessment (PGA) score of cleared/minimal (PGA = 0/1) were randomized 1 : 4 to group 1 [approved every 12 weeks (q12 wk) maintenance] or group 2 (q12-24 wk; response-based dosing determined by time to loss of PGA = 0/1). Key end points included the number of visits with PGA = 0/1 (primary end point) and ≥ 75% improvement in Psoriasis Area and Severity Index (PASI 75) between weeks 88 and 112, and PGA/PASI responses between weeks 28 and 112. RESULTS: Overall, 378 patients achieved PGA = 0/1 at week 28 and were randomized to group 1 (n = 76) or group 2 (n = 302). Patients in group 1 had numerically greater mean numbers of visits with PGA = 0/1 than group 2 and also with PASI 75 from week 88 to 112. A higher proportion of patients in group 1 (55%) than group 2 (39%) had PGA = 0/1 at all seven visits from week 88 to 112. Maintenance of response was observed with dose-interval extension beyond q12 wk in a subset of patients. Extending the dosing interval did not affect antibody development or safety. CONCLUSIONS: Efficacy was better maintained among week-28 PGA responders randomized to continue q12 wk ustekinumab vs. extending maintenance dosing based on clinical response, although some patients maintained high levels of efficacy with up to q24 wk dosing.


Assuntos
Fármacos Dermatológicos/administração & dosagem , Psoríase/tratamento farmacológico , Ustekinumab/administração & dosagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
10.
Molecules ; 22(5)2017 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-28452944

RESUMO

The health challenges associated with pathogens and ectoparasites highlight the need for effective control approaches. Metal nanoparticles have been proposed as highly effective tools towards combatting different microbial organisms and parasites. The present work reports the antimicrobial and larvicidal potential of biosynthesized Ag/Ag2O nanoparticles using aqueous leaf extract of Eupatorium odoratum (EO). The constituents of the leaf extract act as both reducing and stabilizing agents. The UV-VIS spectra of the nanoparticles showed surface plasmon resonance. The particle size and shape of the nanoparticles was analysed by transmission electron microscopy (TEM). The larvicidal study was carried out using third and fourth instar Culex quinquefasciatus larvae. The mosquito larvae were exposed to varying concentrations of plant extract (EO) and the synthesized nanoparticles, and their percentage of mortality was accounted for at different time intervals of 12 h and 24 h periods of exposure. The nanoparticles were more lethal against third and fourth instars of Culex quinquefasciatus larvae at the 24 h period of exposure with lower lethal concentration values (LC50 = 95.9 ppm; LC90 = 337.5 ppm) and (LC50 = 166.4 ppm; LC90 = 438.7 ppm) compared to the plant extract (LC50 = 396.8 ppm; LC90 = 716.8 ppm and LC50 = 448.3 ppm; LC90 = 803.9 ppm, respectively). The antimicrobial properties of the nanoparticles were established against different clinically-isolated microbial strains and compared to that of the plant extract (EO) and standard antimicrobial drugs. The nanoparticles were generally more active than the plant extract against the selected microbial organisms. The Gram-negative bacterial strains Escheerichua coli and Salmonella typhi were more susceptible towards the nanoparticles compared to the Gram-positive strains and the fungal organism.


Assuntos
Antibacterianos/síntese química , Antifúngicos/síntese química , Inseticidas/síntese química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Animais , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Chromolaena/química , Culex/efeitos dos fármacos , Química Verde , Concentração Inibidora 50 , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Óxidos/química , Folhas de Planta/química , Prata/química , Compostos de Prata/química
11.
Molecules ; 22(5)2017 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-28468278

RESUMO

Synthesis of metallic and semiconductor nanoparticles through physical and chemical routes has been extensively reported. However, green synthesized metal nanoparticles are currently in the limelight due to the simplicity, cost-effectiveness and eco-friendliness of their synthesis. This study explored the use of aqueous leaf extract of Costus afer in the synthesis of silver nanoparticles (CA-AgNPs). The optical and structural properties of the resulting silver nanoparticles were studied using UV-visible spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infra-red spectrophotometer (FTIR). TEM images of the silver nanoparticles confirmed the existence of monodispersed spherical nanoparticles with a mean size of 20 nm. The FTIR spectra affirmed the presence of phytochemicals from the Costus afer leaf extract on the surface of the silver nanoparticles. The electrochemical characterization of a CA-AgNPs/multiwalled carbon nanotubes (MWCNT)-modified electrode was carried out to confirm the charge transfer properties of the nanocomposites. The comparative study showed that the CA-AgNPs/MWCNT-modified electrode demonstrated faster charge transport behaviour. The anodic current density of the electrodes in Fe(CN)6]4-/[Fe(CN)6]3- redox probe follows the order: GCE/CA-Ag/MWCNT (550 mA/cm²) > GCE/MWCNT (270 mA/cm²) > GCE (80 mA/cm²) > GCE/CA-Ag (7.93 mA/cm²). The silver nanoparticles were evaluated for their antibacterial properties against Gram negative (Escherichia coli, Klebsiella pneumonia, Pseudomonas aeruginosa) and Gram positive (Bacillus subtilis and Staphylococcus aureus) pathogens. The nanoparticles exhibited better inhibition of the bacterial strains compared to the precursors (leaf extract of Costus afer and silver nitrate). Furthermore, the ability of the nanoparticles to scavenge DPPH radicals at different concentrations was studied using the DPPH radical scavenging assay and compared to that of the leaf extract and ascorbic acid. The nanoparticles were better DPPH scavengers compared to the leaf extract and their antioxidant properties compared favorably the antioxidant results of ascorbic acid. The green approach to nanoparticles synthesis carried out in this research work is simple, non-polluting, inexpensive and non-hazardous.


Assuntos
Antibacterianos/química , Sequestradores de Radicais Livres/química , Nanopartículas Metálicas/química , Nanocompostos/química , Antibacterianos/farmacologia , Compostos de Bifenilo/química , Varredura Diferencial de Calorimetria , Costus/química , Eletroquímica , Eletrodos , Escherichia coli/efeitos dos fármacos , Sequestradores de Radicais Livres/farmacologia , Radicais Livres/química , Testes de Sensibilidade Microbiana , Nanotubos de Carbono/química , Tamanho da Partícula , Picratos/química , Extratos Vegetais/química , Folhas de Planta/química , Prata , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos
12.
Hell J Nucl Med ; 20(1): 51-56, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28315909

RESUMO

Hashimoto's thyroiditis (HT) is a chronic autoimmune thyroid disease caused by an interaction between genetic factors and environmental conditions, both of which are yet to be fully understood. The management of HT depends on its clinical manifestations, commonly including diffuse or nodular goiter with euthyroidism, subclinical hypothyroidism and permanent hypothyroidism. However, in most cases of patients with HT, lifelong levothyroxine substitution is required. The additional role of diet for the management of HT is usually overlooked. A literature search regarding the importance and the influence of iodine, selenium, vitamin D and gluten on HT was conducted. In HT careful supplementation of possible deficiencies is recommended for the dietary management of these patients. The use of a diet low in gluten among HT patients with or without celiac disease (CD) is discussed.


Assuntos
Dieta Livre de Glúten/métodos , Suplementos Nutricionais , Glutens/uso terapêutico , Doença de Hashimoto/dietoterapia , Iodo/uso terapêutico , Selênio/uso terapêutico , Terapia Combinada/métodos , Dietoterapia , Medicina Baseada em Evidências , Doença de Hashimoto/diagnóstico , Humanos , Resultado do Tratamento , Vitamina D
14.
Eat Weight Disord ; 26(1): 405-406, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31955386
17.
Hell J Nucl Med ; 18(3): 222-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26637501

RESUMO

OBJECTIVE: The aim of this study was to investigate vitamin D status by measuring serum 25(OH)D levels in euthyroid patients with Hashimoto's thyroiditis (HT) who lived and worked on the sunny island of Crete, Greece, and to evaluate whether vitamin D3 supplementation is beneficial for the management of HT patients with vitamin D deficiency. SUBJECTS AND METHODS: We studied 218 HT patients, euthyroid Caucasian Cretan Greek citizens: 180 females and 38 males. Among these patients, 186 (85.3%) had vitamin D deficiency defined as serum 25(OH)D levels < 30 ng/mL. The mean age of all these 218 HT patients was 35.3 ± 8.5 years. The mean age of the 186 vitamin D deficient HT patients (173 females and 13 males) was 37.3 ± 5.6 years. The 186 vitamin D deficient HT patients received vitamin D3 (cholecalciferol, CF) orally, 1200-4000 IU, every day for 4 months aiming to maintain serum 25(OH)D levels ≥ 40 ng/mL. Anthropometric characteristics (height, weight, waist circumference), systolic and diastolic blood pressure, serum concentration of 25(OH)D, thyrotropin (TSH), free thyroxine (FT4), anti-thyroid peroxidase (anti-TPO), antithyroglobulin (anti-TG), calcium and phosphorus levels and thyroid and kidney sonographic findings were recorded and measured before and after CF administration. RESULTS: There was a significant negative correlation only between serum 25(OH)D levels and anti-TPO levels among all 218 HT patients. Also, anti-TPO levels were significantly higher in 186/218 vitamin D deficient HT patients compared to 32/218 HT patients with no vitamin D deficiency (364 ± 181IU/mL versus 115.8 ± 37.1IU/mL, P<0.0001). Supplementation of CF in 186 vitamin D deficient HT patients caused a significant decrease (20.3%) in serum anti-TPO levels. Although at the end of the 4 months period of the study body mass index (BMI), serum anti-TG and TSH levels decreased by 2.2%, 5.3% and 4% respectively, these differences were not significant. No changes in the sonographic findings were observed. CONCLUSION: The majority (85.3%) of the Greek Caucasian patients with HT studied who lived and worked in Crete had low serum 25(OH)D levels inversely correlated with serum anti-TPO thyroid antibodies. After 4 months of CF supplementation in the 186 HT patients with vitamin D deficiency, a significant decrease (20.3%) of serum anti-TPO levels was found. These findings suggest that vitamin D deficiency may be related to pathogenesis of HT and that its supplementation could contribute to the treatment of patients with HT.


Assuntos
Suplementos Nutricionais , Doença de Hashimoto/sangue , Doença de Hashimoto/dietoterapia , Deficiência de Vitamina D/dietoterapia , Vitamina D/análogos & derivados , Vitamina D/administração & dosagem , Administração Oral , Adulto , Biomarcadores/sangue , Causalidade , Comorbidade , Feminino , Grécia/epidemiologia , Doença de Hashimoto/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/epidemiologia , Adulto Jovem
19.
Br J Surg ; 101(12): 1566-75, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25209438

RESUMO

BACKGROUND: Roux-en-Y gastric bypass may lead to impaired calcium uptake. Therefore, operation-specific effects of gastric bypass and vertical banded gastroplasty on bone mineral density (BMD) were examined in a randomized clinical trial. Bone resorption markers and mechanisms of decreased calcium uptake after gastric bypass were investigated using blood and endoscopic samples from two additional patient cohorts. METHODS: Total BMD and non-weight-bearing skull BMD were measured by dual-energy X-ray absorptiometry at baseline, and 1 and 6 years after gastric bypass or vertical banded gastroplasty in patients who were not receiving calcium supplements. Bone resorption markers in serum and calcium uptake mechanisms in jejunal mucosa biopsies were analysed after gastric bypass by proteomics including radioimmunoassay, gel electrophoresis and mass spectrometry. RESULTS: One year after surgery, weight loss was similar after gastric bypass and vertical banded gastroplasty. There was a moderate decrease in skull BMD after gastric bypass, but not after vertical banded gastroplasty (P < 0·001). Between 1 and 6 years after gastric bypass, skull BMD and total BMD continued to decrease (P = 0·001). C-terminal telopeptide levels in serum had increased twofold by 18 months after gastric bypass. Proteomic analysis of the jejunal mucosa revealed decreased levels of heat-shock protein 90ß, a co-activator of the vitamin D receptor, after gastric bypass. Despite increased vitamin D receptor levels, expression of the vitamin D receptor-regulated calcium transporter protein TRPV6 decreased. CONCLUSION: BMD decreases independently of weight after gastric bypass. Bone loss might be attributed to impaired calcium absorption caused by decreased activation of vitamin D-dependent calcium absorption mechanisms mediated by heat-shock protein 90ß and TRPV6.


Assuntos
Densidade Óssea/fisiologia , Cálcio/metabolismo , Intestino Delgado/metabolismo , Peso Corporal , Reabsorção Óssea/metabolismo , Canais de Cálcio/fisiologia , Feminino , Derivação Gástrica/efeitos adversos , Gastroplastia/efeitos adversos , Humanos , Absorção Intestinal/fisiologia , Masculino , Glicoproteínas de Membrana/fisiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/metabolismo , Estudos Prospectivos , Receptores de Calcitriol/fisiologia , Canais de Cátion TRPV/fisiologia
20.
Bioorg Med Chem ; 22(15): 3957-70, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25002233

RESUMO

The MDR-involved human GSTA1-1, an important isoenzyme overexpressed in several tumors leading to chemotherapeutic-resistant tumour cells, has been targeted by 2,2'-dihydroxybenzophenones and some of their carbonyl N-analogues, as its potential inhibitors. A structure-based library of the latter was built-up by a nucleophilic cleavage of suitably substituted xanthones to 2,2'-dihydroxy-benzophenones (5-9) and subsequent formation of their N-derivatives (oximes 11-13 and N-acyl hydrazones 14-16). Screening against hGSTA1-1 led to benzophenones 6 and 8, and hydrazones 14 and 16, having the highest inhibition potency (IC50 values in the range 0.18 ± 0.02 to 1.77 ± 0.10 µM). Enzyme inhibition kinetics, molecular modeling and docking studies showed that they interact primarily at the CDNB-binding catalytic site of the enzyme. In addition, the results from cytotoxicity studies with human colon adenocarcinoma cells showed low LC50 values for benzophenone 6 and its N-acyl hydrazone analogue 14 (31.4 ± 0.4 µM and 87 ± 1.9 µM, respectively), in addition to the strong enzyme inhibition profile (IC50(6)=1,77 ± 0.10 µM; IC50(14)=0.33 ± 0.05 µM). These structures may serve as leads for the design of new potent mono- and bi-functional inhibitors and pro-drugs against human GTSs.


Assuntos
Benzofenonas/química , Inibidores Enzimáticos/química , Glutationa Transferase/antagonistas & inibidores , Isoenzimas/antagonistas & inibidores , Benzofenonas/metabolismo , Benzofenonas/toxicidade , Sítios de Ligação , Domínio Catalítico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/toxicidade , Glutationa Transferase/metabolismo , Humanos , Isoenzimas/metabolismo , Cinética , Simulação de Acoplamento Molecular , Ligação Proteica , Relação Estrutura-Atividade , Termodinâmica
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