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1.
Mol Ther ; 29(6): 2041-2052, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-33609732

RESUMO

Oligonucleotide therapies offer precision treatments for a variety of neurological diseases, including epilepsy, but their deployment is hampered by the blood-brain barrier (BBB). Previous studies showed that intracerebroventricular injection of an antisense oligonucleotide (antagomir) targeting microRNA-134 (Ant-134) reduced evoked and spontaneous seizures in animal models of epilepsy. In this study, we used assays of serum protein and tracer extravasation to determine that BBB disruption occurring after status epilepticus in mice was sufficient to permit passage of systemically injected Ant-134 into the brain parenchyma. Intraperitoneal and intravenous injection of Ant-134 reached the hippocampus and blocked seizure-induced upregulation of miR-134. A single intraperitoneal injection of Ant-134 at 2 h after status epilepticus in mice resulted in potent suppression of spontaneous recurrent seizures, reaching a 99.5% reduction during recordings at 3 months. The duration of spontaneous seizures, when they occurred, was also reduced in Ant-134-treated mice. In vivo knockdown of LIM kinase-1 (Limk-1) increased seizure frequency in Ant-134-treated mice, implicating de-repression of Limk-1 in the antagomir mechanism. These studies indicate that systemic delivery of Ant-134 reaches the brain and produces long-lasting seizure-suppressive effects after systemic injection in mice when timed with BBB disruption and may be a clinically viable approach for this and other disease-modifying microRNA therapies.


Assuntos
Antagomirs/genética , Barreira Hematoencefálica/metabolismo , Epilepsia/genética , Epilepsia/terapia , Animais , Antagomirs/administração & dosagem , Barreira Hematoencefálica/patologia , Gerenciamento Clínico , Modelos Animais de Doenças , Suscetibilidade a Doenças , Regulação da Expressão Gênica , Inativação Gênica , Técnicas de Transferência de Genes , Predisposição Genética para Doença , Terapia Genética , Camundongos , MicroRNAs/genética , Interferência de RNA , Resultado do Tratamento
2.
Trop Anim Health Prod ; 54(6): 382, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36378348

RESUMO

Two experiments were conducted to evaluate the effect of supplementation with two sources of non-protein nitrogen at different feeding times on the performance, ingestive behavior, and rumen metabolism of growing Nellore bulls during the dry season. Exp. 1: One hundred and twenty Nellore bulls, weighing 206 ± 39 kg of initial body weight (BW) and 12 months of age, were divided into 20 paddocks, and they were used in randomized block design in a 2 × 2 factorial arrangement to evaluate performance and ingestive behavior. Exp. 2: 12 rumen cannulated animals with 509 ± 59 BW, divided into 4 paddocks, were used in a triple Latin square 4 × 4 in a 2 × 2 factorial arrangement to evaluate metabolism. The factors were 2 non-protein nitrogen sources (urea or slow-release urea) and 2 feeding times (07:00 or 13:00 at 4 g/kg BW of supplement). There was no influence of non-protein sources, supplementation time, or their interaction on the grazing time or the trough time during daytime, nighttime, or total (P ≥ 0.16). There were no interactions or factor effects on ADG (P ≥ 0.45) or final body weight (P ≥ 0.39). There was an interaction between supplementation time and collection time (P < 0.01) on ruminal pH. Animals supplemented in the morning had greater total SCFA at 18 h after supplementation (P = 0.03). The supplementation time and the non-protein nitrogen sources did not alter the ingestive behavior or animal performance of young Nellore cattle.


Assuntos
Nitrogênio , Rúmen , Animais , Bovinos , Masculino , Ração Animal/análise , Peso Corporal , Dieta/veterinária , Suplementos Nutricionais/análise , Digestão , Nitrogênio/metabolismo , Rúmen/metabolismo , Estações do Ano , Ureia/metabolismo
3.
Am J Ind Med ; 64(11): 952-959, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34379326

RESUMO

BACKGROUND: In low- and middle-income countries, such as Brazil, studies on the causes of death in asbestos-exposed workers are scarce. METHODS: A cohort study was performed involving 988 males who had worked in the asbestos-cement industry in the state of São Paulo, with a total of 12,217 person-years of observation between 1995 and 2016. The standardized mortality ratio (SMR) stratified by age was calculated as the ratio between the observed rate and the expected rate in the state of São Paulo. RESULTS: Increased SMRs were observed for overall mortality (SMR 1.1, 95% confidence interval [CI], 0.98-1.23) and mortality due to pleural malignant neoplasms (MN) (SMR, 69.4; 95% CI, 22.55-162.1), asbestosis (SMR, 975.7; 95% CI, 396.4-2031), peritoneal MN (SMR, 5.0; 95% CI, 0.13-27.78), laryngeal MN (SMR, 1.4; 95% CI, 0.30-4.20), and pulmonary MN (SMR, 1.5; 95% CI, 0.82-2.64). CONCLUSION: The present study highlights the damage caused by asbestos exposure and reinforces the existing evidence of a causal association between exposure and increased mortality due to pleural MN, pulmonary MN, and asbestosis.


Assuntos
Amianto , Doenças Profissionais , Exposição Ocupacional , Neoplasias Pleurais , Brasil/epidemiologia , Causas de Morte , Estudos de Coortes , Humanos , Masculino , Exposição Ocupacional/efeitos adversos
4.
J Dairy Sci ; 104(11): 11634-11645, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34454761

RESUMO

The objective of this study was to evaluate the effects of feed additives on intake and digestibility of nutrients, milk yield and composition, feeding behavior, and physiological parameters of dairy cows during the hot season. Forty Holstein cows were assigned to a randomized block design experiment with a 2 × 2 factorial treatment arrangement to evaluate (1) control diet without inclusion of additives; (2) monensin (MON), 20 mg/kg diet dry matter sodium monensin (Rumensin; Elanco); (3) Milk Sacc+ (MS+), inclusion of 40 g/cow per d of Milk Sacc+ (a blend of live yeast and organic minerals, Alltech); and (4) combination of MON and MS+. The average temperature-humidity index throughout the experimental period was 73 ± 2.84 (standard deviation). The experiment lasted 11 wk, including 2 preliminary weeks for covariate adjustments. Cows fed MS+ increased dry matter intake (% body weight), milk yield, 3.5% fat-corrected milk, and solids yield, and cows fed MON had greater milk urea nitrogen content in comparison with counterparts. Feeding MS+ increased the intake of feed particles with size between 8 and 19 mm and decreased the intake of particles shorter than 4 mm compared with other treatments. Rumination time (min/d) and chewing time (min/kg of neutral detergent fiber) were lower for cows fed MS+. Physiologic parameters (i.e., heart and respiratory rates, and body temperature) were not affected by the treatments. Overall, the use of monensin did not differ from control, and Milk Sacc+ improved performance of cows.


Assuntos
Monensin , Saccharomyces cerevisiae , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Digestão , Feminino , Lactação , Leite , Minerais , Monensin/farmacologia , Rúmen , Estações do Ano
5.
Histopathology ; 77(2): 186-197, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32443177

RESUMO

AIMS: Brazil ranks high in the number of coronavirus disease 19 (COVID-19) cases and the COVID-19 mortality rate. In this context, autopsies are important to confirm the disease, determine associated conditions, and study the pathophysiology of this novel disease. The aim of this study was to assess the systemic involvement of COVID-19. In order to follow biosafety recommendations, we used ultrasound-guided minimally invasive autopsy (MIA-US), and we present the results of 10 initial autopsies. METHODS AND RESULTS: We used MIA-US for tissue sampling of the lungs, liver, heart, kidneys, spleen, brain, skin, skeletal muscle and testis for histology, and reverse transcription polymerase chain reaction to detect severe acute respiratory syndrome coronavirus 2 RNA. All patients showed exudative/proliferative diffuse alveolar damage. There were intense pleomorphic cytopathic effects on the respiratory epithelium, including airway and alveolar cells. Fibrinous thrombi in alveolar arterioles were present in eight patients, and all patients showed a high density of alveolar megakaryocytes. Small thrombi were less frequently observed in the glomeruli, spleen, heart, dermis, testis, and liver sinusoids. The main systemic findings were associated with comorbidities, age, and sepsis, in addition to possible tissue damage due to the viral infection, such as myositis, dermatitis, myocarditis, and orchitis. CONCLUSIONS: MIA-US is safe and effective for the study of severe COVID-19. Our findings show that COVID-19 is a systemic disease causing major events in the lungs and with involvement of various organs and tissues. Pulmonary changes result from severe epithelial injury and microthrombotic vascular phenomena. These findings indicate that both epithelial and vascular injury should be addressed in therapeutic approaches.


Assuntos
Autopsia/métodos , COVID-19/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Ultrassonografia
6.
J Org Chem ; 83(21): 13604-13611, 2018 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-30284445

RESUMO

We describe the synthesis of α-alkynyl-ß-substituted cyclic ketones and analogue chromanones via one-pot Michael addition/hypervalent iodine-based α-alkynylation. Cu(I)-catalyzed Michael addition using either alkyl-aluminum or Grignard reagents, followed by diastereoselective electrophilic alkynylation of the resulting enolate by 1-ethynyl-1λ3,2-benziodoxol-3(1H)-one (EBX) resulted in the α-alkynyl-ß-substituted cyclic ketones or chromanones within 34-89% yield (16 examples). The reaction was successfully upscaled to the 5 mmol scale, and further functionalization of a model alkynylated ketone was demonstrated.

7.
J Org Chem ; 82(22): 11787-11791, 2017 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-28817768

RESUMO

The synthesis of homopropargylic alcohols under metal-free and mild condition is described. This transformation is based on a one-pot procedure involving sequential α-alkynylation of acyclic aldehydes using hypervalent iodine reagents and borohydride reduction. The chemistry exhibits broad substrate scope and good scalability, providing a convenient route for the α-alkynylation of aldehydes along with the formation of a quaternary carbon center. The applicability of the method is demonstrated by the gram-scale synthesis of the key synthetic precursor of botulinum toxin inhibitors.

9.
J Org Chem ; 81(5): 2174-81, 2016 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-26866897

RESUMO

The iodine(III)-mediated asymmetric oxidative rearrangement of 1,2-dihydronaphthalenes was investigated to prepare optically active 1-substituted indanes. The chiral hypervalent iodine species is generated in situ from a chiral aryl iodide, prepared in 94% yield in one step. This metal-free protocol was applied to different cyclic alkenes, substituted with oxygen, with nitrogen, or at position 1 with aryl or methyl. Indanes can be isolated as an acetal or alcohol in up to 78% ee.

10.
Int J Legal Med ; 130(4): 1089-1099, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27221535

RESUMO

INTRODUCTION: Radiological techniques such as non-enhanced post-mortem computed tomography (PMCT) play an increasingly important role in death investigations, especially in cases of non-medicolegal context of death, where the consent of the next of kin is required to perform autopsy. Such consent is often difficult to obtain for deceased children, and radiological methods may be an acceptable alternative. The aim of our study was to evaluate the performance of PMCT explorations compared to medicolegal conventional autopsies in children and its potential usefulness in non-medicolegal situations. METHODS: We retrospectively reviewed a group of 26 children aged 0-12 years who died of different causes, which were investigated by both conventional autopsy and PMCT. We compared the findings extracted from radiological and autopsy reports. All findings were grouped according to their importance with respect to cause of death and to the anatomical structure they covered: organs, vascular system, soft tissue, and skeletal system. RESULTS: A significantly larger number of findings were detected by autopsy compared to PMCT. Autopsy proved to be superior to PMCT, notably at detecting organ, soft tissue, and vascular findings, while PMCT was superior at detecting bone findings. However, no statistically significant differences were found between the methods concerning the essential findings used to define the cause of death. CONCLUSIONS: In children, PMCT was less sensitive than conventional autopsy for detecting general findings. However, most essential findings were detected by both methods. PMCT was superior to autopsy for the detection of bone lesions in children. ADVANCES IN KNOWLEDGE: Up to today, very rare literature exists concerning PMCT in children, especially in a forensic setting. This article investigates the advantages and limitations of PMCT compared to autopsy in a unique study group and discusses possibilities for future developments.


Assuntos
Autopsia/métodos , Patologia Legal/métodos , Tomografia Computadorizada Multidetectores , Causas de Morte , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos
11.
Respir Res ; 16: 18, 2015 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-25848680

RESUMO

BACKGROUND: Diesel exhaust particles (DEPs) are deposited into the respiratory tract and are thought to be a risk factor for the development of diseases of the respiratory system. In healthy individuals, the timing and mechanisms of respiratory tract injuries caused by chronic exposure to air pollution remain to be clarified. METHODS: We evaluated the effects of chronic exposure to DEP at doses below those found in a typical bus corridor in Sao Paulo (150 µg/m3). Male BALB/c mice were divided into mice receiving a nasal instillation: saline (saline; n = 30) and 30 µg/10 µL of DEP (DEP; n = 30). Nasal instillations were performed five days a week, over a period of 90 days. Bronchoalveolar lavage (BAL) was performed, and the concentrations of interleukin (IL)-4, IL-10, IL-13 and interferon-gamma (INF-γ) were determined by ELISA-immunoassay. Assessment of respiratory mechanics was performed. The gene expression of Muc5ac in lung was evaluated by RT-PCR. The presence of IL-13, MAC2+ macrophages, CD3+, CD4+, CD8+ T cells and CD20+ B cells in tissues was analysed by immunohistochemistry. Bronchial thickness and the collagen/elastic fibers density were evaluated by morphometry. We measured the mean linear intercept (Lm), a measure of alveolar distension, and the mean airspace diameter (D0) and statistical distribution (D2). RESULTS: DEP decreased IFN-γ levels in BAL (p = 0.03), but did not significantly alter IL-4, IL-10 and IL-13 levels. MAC2+ macrophage, CD4+ T cell and CD20+ B cell numbers were not altered; however, numbers of CD3+ T cells (p ≤ 0.001) and CD8+ T cells (p ≤ 0.001) increased in the parenchyma. Although IL-13 (p = 0.008) expression decreased in the bronchiolar epithelium, Muc5ac gene expression was not altered in the lung of DEP-exposed animals. Although respiratory mechanics, elastic and collagen density were not modified, the mean linear intercept (Lm) was increased in the DEP-exposed animals (p ≤ 0.001), and the index D2 was statistically different (p = 0.038) from the control animals. CONCLUSION: Our data suggest that nasal instillation of low doses of DEP over a period of 90 days results in alveolar enlargement in the pulmonary parenchyma of healthy mice.


Assuntos
Poluentes Atmosféricos/toxicidade , Pneumonia/induzido quimicamente , Alvéolos Pulmonares/efeitos dos fármacos , Emissões de Veículos/toxicidade , Animais , Brasil , Líquido da Lavagem Broncoalveolar/imunologia , Colágeno/metabolismo , Citocinas/imunologia , Citocinas/metabolismo , Tecido Elástico/metabolismo , Mediadores da Inflamação/metabolismo , Subpopulações de Linfócitos/efeitos dos fármacos , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Mucina-5AC/genética , Mucina-5AC/metabolismo , Pneumonia/imunologia , Pneumonia/metabolismo , Pneumonia/patologia , Pneumonia/fisiopatologia , Alvéolos Pulmonares/imunologia , Alvéolos Pulmonares/metabolismo , Alvéolos Pulmonares/patologia , Alvéolos Pulmonares/fisiopatologia , RNA Mensageiro/metabolismo , Mecânica Respiratória/efeitos dos fármacos , Fatores de Tempo
12.
Malar J ; 14: 508, 2015 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-26682750

RESUMO

BACKGROUND: The anti-malarials quinine and artemisinin were isolated from traditionally used plants (Cinchona spp. and Artemisia annua, respectively). The synthetic quinoline anti-malarials (e.g. chloroquine) and semi-synthetic artemisinin derivatives (e.g. artesunate) were developed based on these natural products. Malaria is endemic to the Amazon region where Plasmodium falciparum and Plasmodium vivax drug-resistance is of concern. There is an urgent need for new anti-malarials. Traditionally used Amazonian plants may provide new treatments for drug-resistant P. vivax and P. falciparum. Herein, the in vitro and in vivo antiplasmodial activity and cytotoxicity of medicinal plant extracts were investigated. METHODS: Sixty-nine extracts from 11 plant species were prepared and screened for in vitro activity against P. falciparum K1 strain and for cytotoxicity against human fibroblasts and two melanoma cell lines. Median inhibitory concentrations (IC50) were established against chloroquine-resistant P. falciparum W2 clone using monoclonal anti-HRPII (histidine-rich protein II) antibodies in an enzyme-linked immunosorbent assay. Extracts were evaluated for toxicity against murine macrophages (IC50) and selectivity indices (SI) were determined. Three extracts were also evaluated orally in Plasmodium berghei-infected mice. RESULTS: High in vitro antiplasmodial activity (IC50 = 6.4-9.9 µg/mL) was observed for Andropogon leucostachyus aerial part methanol extracts, Croton cajucara red variety leaf chloroform extracts, Miconia nervosa leaf methanol extracts, and Xylopia amazonica leaf chloroform and branch ethanol extracts. Paullinia cupana branch chloroform extracts and Croton cajucara red variety leaf ethanol extracts were toxic to fibroblasts and or melanoma cells. Xylopia amazonica branch ethanol extracts and Zanthoxylum djalma-batistae branch chloroform extracts were toxic to macrophages (IC50 = 6.9 and 24.7 µg/mL, respectively). Andropogon leucostachyus extracts were the most selective (SI >28.2) and the most active in vivo (at doses of 250 mg/kg, 71% suppression of P. berghei parasitaemia versus untreated controls). CONCLUSIONS: Ethnobotanical or ethnopharmacological reports describe the anti-malarial use of these plants or the antiplasmodial activity of congeneric species. No antiplasmodial activity has been demonstrated previously for the extracts of these plants. Seven plants exhibit in vivo and or in vitro anti-malarial potential. Future work should aim to discover the anti-malarial substances present.


Assuntos
Antimaláricos/farmacologia , Extratos Vegetais/farmacologia , Plantas/química , Plasmodium falciparum/efeitos dos fármacos , Animais , Antimaláricos/isolamento & purificação , Antimaláricos/toxicidade , Brasil , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Humanos , Concentração Inibidora 50 , Malária/tratamento farmacológico , Camundongos Endogâmicos BALB C , Parasitemia/tratamento farmacológico , Testes de Sensibilidade Parasitária , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Plasmodium berghei/efeitos dos fármacos , Resultado do Tratamento
13.
J Toxicol Environ Health A ; 78(4): 215-25, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25674825

RESUMO

Diesel exhaust particles (DEP) contain organic and inorganic elements that produce damage to the respiratory epithelium. The aim of this study was to determine the mucus profile of tracheal explants exposed to either crude diesel exhaust particles (DEP) or DEP treated with nitric acid (DEP/NA), with hexane (DEP/HEX), or with methanol (DEP/MET) at concentrations of 50 and 100 µg/ml for 30 and 60 min. Tracheal explants were subjected to morphometric analyses to study acidic (AB+), neutral (PAS+), and mixed (AB+/PAS+) mucus production and vacuolization (V). Incubation with 50 µg/ml crude DEP resulted in a rise in acid mucus production, an increase in vacuolization at 30 min, and reduction in neutral mucus at 30 and 60 min. Tracheas exposed to DEP/MET at 50 µg/ml for 30 or 60 min resulted in a significant decrease in neutral mucus production and an elevation in acid mucus production. DEP/HEX increased vacuolization at both 50 and 100 µg/ml at 30 and 60 min of exposure. Treatment with 50 µg/ml for 30 or 60 min significantly elevated mixed mucus levels. These results suggest that DEP appear to be more toxic when administered in combination with HEX or MET. DEP/MET modified the mucus profile of the epithelium, while DEP/HEX altered mucus extrusion, and these responses might be due to bioavailability of individual elements in DEP fractions.


Assuntos
Mucinas/metabolismo , Traqueia/efeitos dos fármacos , Emissões de Veículos/toxicidade , Poluentes Atmosféricos/toxicidade , Animais , Hexanos/química , Técnicas In Vitro , Metanol/química , Camundongos , Camundongos Endogâmicos BALB C , Muco/metabolismo , Ácido Nítrico/química , Traqueia/metabolismo
14.
Molecules ; 20(1): 1475-94, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25599151

RESUMO

A versatile and metal-free approach for the synthesis of carbocycles and of heterocycles bearing seven- and eight-membered rings is described. The strategy is based on ring expansion of 1-vinylcycloalkanols (or the corresponding silyl or methyl ether) mediated by the hypervalent iodine reagent HTIB (PhI(OH)OTs). Reaction conditions can be easily adjusted to give ring expansion products bearing different functional groups. A route to medium-ring lactones was also developed.


Assuntos
Compostos Heterocíclicos/química , Iodo/química , Metais/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Compostos Heterocíclicos/farmacologia , Humanos , Modelos Moleculares , Compostos de Organossilício/química
15.
Malar J ; 13: 317, 2014 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-25124944

RESUMO

BACKGROUND: Carapa guianensis is a cultivable tree used by traditional health practitioners in the Amazon region to treat several diseases and particularly symptoms related to malaria. Abundant residual pressed seed material (RPSM) results as a by-product of carapa or andiroba oil production. The objective of this study was to evaluate the in vitro and in vivo anti-malarial activity and cytotoxicity of limonoids isolated from C. guaianensis RPSM. METHODS: 6α-acetoxyepoxyazadiradione (1), andirobin (2), 6α-acetoxygedunin (3) and 7-deacetoxy-7-oxogedunin (4) (all isolated from RPSM using extraction and chromatography techniques) and 6α-hydroxy-deacetylgedunin (5) (prepared from 3) were evaluated using the micro test on the multi-drug-resistant Plasmodium falciparum K1 strain. The efficacy of limonoids 3 and 4 was then evaluated orally and subcutaneously in BALB/c mice infected with chloroquine-sensitive Plasmodium berghei NK65 strain in the 4-day suppressive test. RESULTS: In vitro, limonoids 1-5 exhibited median inhibition concentrations (IC50) of 20.7-5.0 µM, respectively. In general, these limonoids were not toxic to normal cells (MRC-5 human fibroblasts). In vivo, 3 was more active than 4. At oral doses of 50 and 100 mg/kg/day, 3 suppressed parasitaemia versus untreated controls by 40 and 66%, respectively, evidencing a clear dose-response. CONCLUSION: 6α-acetoxygedunin is an abundant natural product present in C. guianensis residual seed materials that exhibits significant in vivo anti-malarial properties.


Assuntos
Antimaláricos/farmacologia , Limoninas/farmacologia , Meliaceae/química , Extratos Vegetais/farmacologia , Plasmodium berghei/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos , Animais , Antimaláricos/uso terapêutico , Linhagem Celular , Feminino , Humanos , Concentração Inibidora 50 , Limoninas/uso terapêutico , Malária/tratamento farmacológico , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/uso terapêutico , Sementes/química
16.
Bioorg Med Chem Lett ; 24(12): 2631-4, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24813729

RESUMO

Ellipticine has been shown previously to exhibit excellent in vitro antiplasmodial activity and in vivo antimalarial properties that are comparable to those of the control drug chloroquine in a mouse malaria model. Ellipticine derivatives and analogs exhibit antimalarial potential however only a few have been studied to date. Herein, ellipticine and a structural analog were isolated from Aspidosperma vargasii bark. A-ring brominated and nitrated ellipticine derivatives exhibit good in vitro inhibition of Plasmodium falciparum K1 and 3D7 strains. Several of the compounds were found not to be toxic to human fetal lung fibroblasts. 9-Nitroellipticine (IC50=0.55µM) exhibits greater antiplasmodial activity than ellipticine. These results are further evidence of the antimalarial potential of ellipticine derivatives.


Assuntos
Antimaláricos/farmacologia , Elipticinas/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Animais , Antimaláricos/síntese química , Antimaláricos/química , Aspidosperma/química , Cloroquina/química , Cloroquina/farmacologia , Modelos Animais de Doenças , Elipticinas/síntese química , Elipticinas/química , Fibroblastos/efeitos dos fármacos , Humanos , Camundongos , Estrutura Molecular , Casca de Planta/química
17.
J Cutan Pathol ; 41(2): 101-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24219812

RESUMO

BACKGROUND: Hypopigmentation in hypopigmented mycosis fungoides (MF) is thought to result from the action of CD8+ cells on melanocytes. Here, we investigated the immunophenotype and melanocytic markers in hypopigmented MF lesions. METHODS: Specimens of hypopigmented lesions and normal skin from 18 patients with hypopigmented MF and specimens of non-hypopigmented lesions from 8 patients with classic/conventional MF were subjected to neoplastic immunophenotyping and melanocyte immunostaining with Melan-A, tyrosinase, stem cell factor receptor (CD117) and microphthalmia-associated transcription factor (MiTF). RESULTS: The CD8+ immunophenotype was more common in hypopigmented MF lesions (14/18) than in conventional MF lesions (1/8, p = 0.0033). There was a main effect of specimen type (hypopigmented MF lesion, hypopigmented MF normal skin, conventional MF lesion) on the number of melanocytes stained with Melan-A (median number/mm basal membrane, 1.97 vs. 4.77 vs. 5.42, respectively, p = 0.0046), tyrosinase (2.19 vs. 4.02 vs. 5.26, p = 0.0114), CD117 (4.29 vs. 7.81 vs. 5.45, p = 0.0064), and MiTF (2.75 vs. 4.43 vs. 4.98, p = 0.005). CONCLUSIONS: These results confirm previous findings of fewer melanocytes and CD117-positive melanocytes in hypopigmented MF and showed reduced MiTF identification, which is crucial for the function and survival of melanocytes. Thus cytotoxic CD8+ cell action may determine CD117/MiTF dysfunction, causing hypopigmentation.


Assuntos
Hipopigmentação , Melanócitos/patologia , Micose Fungoide , Neoplasias Cutâneas , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Hipopigmentação/metabolismo , Hipopigmentação/patologia , Masculino , Pessoa de Meia-Idade , Micose Fungoide/metabolismo , Micose Fungoide/patologia , Estudos Retrospectivos , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
18.
COPD ; 10(3): 348-56, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23537051

RESUMO

In some patients with chronic asthma clinical and physiological similarities with COPD may exist, such as partial reversibility to bronchodilators and persistent expiratory airflow obstruction. However, pathological data comparing both diseases in patients of similar age and disease severity are scarce. We compared large and small airway dimensions in 12 younger (mean age 32 yrs) and 15 older (mean age 65 yrs) non-smoker adult fatal asthma patients with 14 chronic smokers with severe, fatal COPD (mean age 71 yrs). Using H&E, Movat pentachrome staining and image analysis, we quantified large airway basement membrane (BM) thickness (µm), submucosal gland area and large and small airway inner wall, smooth muscle and outer wall areas. Areas were normalized by BM perimeter (µm(2)/µm). Younger adult fatal asthma patients had thicker BM, smooth muscle, and outer wall areas in both small and large airways when compared to COPD patients. In older asthmatics there was an overlap in BM thickness and airway structure in small airways. Inner wall layer in large and small airway level and submucosal gland areas were similar among groups. In conclusion, there are airway histological structural similarities between fatal asthma and fatal COPD. Older fatal asthmatics present overlapping airway structural features with younger adult fatal asthmatics and severe COPD patients. Our data contributes to a better understanding of asthma pathology in the elderly.


Assuntos
Remodelação das Vias Aéreas , Asma/patologia , Doença Pulmonar Obstrutiva Crônica/patologia , Sistema Respiratório/patologia , Adulto , Idoso , Membrana Basal/patologia , Estudos de Casos e Controles , Morte , Humanos , Pessoa de Meia-Idade , Músculo Liso/patologia , Índice de Gravidade de Doença , Fumar/patologia
19.
Molecules ; 18(9): 11100-30, 2013 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-24025458

RESUMO

The iodine-catalyzed Prins cyclization of homoallylic alcohols and aldehydes was investigated under metal-free conditions and without additives. Anhydrous conditions and inert atmosphere are not required. The reaction of 2-(3,4-dihydronaphthalen-1-yl)propan-1-ol and 21 aldehydes (aliphatic and aromatic) in CH2Cl2 in the presence of 5 mol % of iodine gave 1,4,5,6-tetrahydro-2H-benzo[f]isochromenes in 54%-86% yield. Under similar conditions, the Prins cyclization of six alcohols containing an endocyclic double bond (primary, secondary, or tertiary) led to dihydropyrans in 52%-91% yield. The acyclic homoallylic alcohols gave 4-iodo-tetrahydropyran in 29%-41% yield in the presence of 50 mol % of iodine. This type of substrate is the main limitation of the methodology. The relative configuration of the products was assigned by NMR and X-ray analysis. The mechanism and the ratio of the products are discussed, based on DFT calculations.


Assuntos
Iodo/química , Piranos/síntese química , Álcoois/química , Aldeídos/química , Catálise , Cristalografia por Raios X , Ciclização , Modelos Químicos , Modelos Moleculares , Conformação Molecular , Teoria Quântica , Estereoisomerismo
20.
Angew Chem Int Ed Engl ; 52(49): 13067-70, 2013 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-24281890

RESUMO

Caramboxin: Patients suffering from chronic kidney disease are frequently intoxicated after ingesting star fruit. The main symptoms of this intoxication are named in the picture. Bioguided chemical procedures resulted in the discovery of caramboxin, which is a phenylalanine-like molecule that is responsible for intoxication. Functional experiments in vivo and in vitro point towards the glutamatergic ionotropic molecular actions of caramboxin, which explains its convulsant and neurodegenerative properties.


Assuntos
Injúria Renal Aguda/etiologia , Doenças Transmitidas por Alimentos/etiologia , Frutas/química , Frutas/intoxicação , Síndromes Neurotóxicas/etiologia , Neurotoxinas/intoxicação , Neurotoxinas/toxicidade , Plantas Tóxicas/química , Plantas Tóxicas/intoxicação , Injúria Renal Aguda/terapia , Animais , Produtos Biológicos , Frutas/toxicidade , Hipocampo/efeitos dos fármacos , Humanos , Ratos , Ratos Wistar , Diálise Renal
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