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1.
An Acad Bras Cienc ; 96(suppl 1): e20230382, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422345

RESUMO

Plasmodium falciparum is known to cause severe malaria, current treatment consists in artemisinin-based combination therapy, but resistance can lead to treatment failure. Knowledge concerning P. falciparum essential proteins can be used for searching new antimalarials, among these a potential candidate is shikimate dehydrogenase (SDH), an enzyme part of the shikimate pathway which is responsible for producing endogenous aromatic amino acids. SDH from P. falciparum (PfSDH) is unexplored by the scientific community, therefore, this study aims to establish the first protocol for active PfSDH expression. Putative PfSDH nucleotide sequence was used to construct an optimized expression vector pET28a+PfSDH inserted in E. coli BL21(DE3). As a result, optimal expression conditions were acquired by varying IPTG and temperature through time. Western Blot analysis was applied to verify appropriate PfSDH expression, solubilization and purification started with lysis followed by two-steps IMAC purification. Enzyme activity was measured spectrophotometrically by NADPH oxidation, optimal PfSDH expression occur at 0.1 mM IPTG for 48 hours growing at 37 °C and shaking at 200 rpm, recombinant PfSDH obtained after purification was soluble, pure and its physiological catalysis was confirmed. Thus, this study describes the first protocol for heterologous expression of PfSDH in soluble and active form.


Assuntos
Oxirredutases do Álcool , Escherichia coli , Plasmodium falciparum , Plasmodium falciparum/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Escherichia coli/genética , Isopropiltiogalactosídeo/metabolismo
2.
Drug Chem Toxicol ; : 1-8, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38984405

RESUMO

Mancozeb is a fungicide of the dithiocarbamate functional group, and it is widely used in agriculture to control various fungal diseases. Thus, studies detailing its toxicological characteristics are necessary, as the population may be exposed through the consumption of food or water contaminated with mancozeb. The aim of this study was to evaluate the cytotoxic, genotoxic, and mutagenic potentials of this dithiocarbamate using the Allium cepa L. test system as well as its cytotoxicity in erythrocytes of female rats (Rattus norvegicus). The meristematic roots of A. cepa bulbs were exposed to various concentrations of mancozeb (62.5, 125, 250, and 500 mg/L) for 24, 48, and 72 h to determine cytotoxicity by evaluating the mitotic index (MI), chromosomal aberrations (CA), and nuclear anomalies (NA) for genotoxicity analysis and micronuclei (MN) for mutagenicity analysis. Distilled water and copper sulfate (0.0006 mg/L) were used as the negative control (NC) and positive control (PC), respectively. The MI and the sum of CA and NA of all the mancozeb concentrations showed a significant difference (p ≤ 0.05) in relation to the NC, indicating possible cytotoxicity and genotoxicity induced by mancozeb. Additionally, MN significantly increased with mancozeb concentration from 250 mg/L to 500 mg/L in 24 h when compared to NC. In another study model, mancozeb showed to be cytolytic at concentrations starting from 125 mg/L. Therefore, these results indicate that mancozeb causes cytogenetic alterations and mutagenicity at lower concentrations than those used in agriculture, which emphasizes the need for more care when managing this fungicide.

3.
Drug Chem Toxicol ; 45(5): 2003-2013, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33685320

RESUMO

The diminazene aceturate (C14H15N7.2C4H7NO3) is a chemotherapeutic agent with more than six decades of use, however more studies regarding its toxicity still need to be performed. Thus, the present study determined the acute toxicity (14 days) of diminazene acetate (DIZE) in male and female swiss mice by changes in body mass, food consumption, biochemical and hematological parameters, locomotor activity and motor coordination. DIZE was administered at a single dose (1000 and 2000 mg/kg) orally. In addition, in vitro antioxidant capacity, hemolytic activity, toxicity in Artemia salina and in silico evaluation were also performed. The results obtained include several signs of toxicity (hypoactivity, loss of the straightening reflex and tachycardia), reduction of behavioral activity (locomotor activity and motor coordination) and significant changes (p < 0.05) in biochemical and hematological parameters. According to the in silico study, the DIZE can be classified based on the mean lethal dose (LD50) in category 4 (300 mg/kg < LD50 ≤ 2000 mg/kg, ProTox-II) or 3 (50 mg/kg < LD50 ≤ 300 mg/kg, AdmetSAR 1.0). Additionally, DIZE (30.3-969.9 nM) was not toxic to A. salina in the first 48 hours of treatment and was not cytotoxic to rat red blood cells after induced hemolysis. In vitro results indicated low antioxidant capacity against DPPH• and ABTS•+ radicals. Therefore, DIZE induces several adverse effects with influence on the central nervous system, changes in hematological and biochemical parameters and even mortality at the highest dose. However, absence of toxicity was observed in A. salina and rats red blood cells.


Assuntos
Antiparasitários , Diminazena , Enzima de Conversão de Angiotensina 2 , Animais , Antioxidantes , Antiparasitários/uso terapêutico , Diminazena/análogos & derivados , Diminazena/toxicidade , Feminino , Masculino , Camundongos , Peptidil Dipeptidase A , Ratos , Ratos Wistar
4.
Antimicrob Agents Chemother ; 64(11)2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-32816737

RESUMO

Praziquantel is currently the only drug available to treat schistosomiasis, a disease of enormous public health significance caused by a blood fluke of the genus Schistosoma Diminazene, a drug approved by the FDA, has been successfully used to treat diseases caused by blood protozoan parasites. In this study, we evaluated the antiparasitic properties of diminazene against Schistosoma mansoniex vivo and in mice harboring either chronic or early S. mansoni infections. In vitro, we monitored phenotypic and tegumental changes as well as the effects of the drug on pairing and egg production. In mice infected with either adult (chronic infection) or immature (early infection) worms, diminazene was administered intraperitoneally (10 to 100 mg/kg of body weight) or by oral gavage (100 to 400 mg/kg), and we studied the influence of the drug on worm burden and egg production. Liver and spleen pathologies and serum aminotransferase levels were also analyzed. In vitro, 50% effective concentrations (EC50) and EC90 revealed that diminazene is able to kill both immature and adult parasites, and its effect was time and concentration dependent. In addition, confocal laser scanning microscopy showed morphological alterations in the teguments of schistosomes. In an animal model, the influence of the drug on worm burden, egg production, hepatomegaly, and splenomegaly depended on the dosing regimen applied and the route of administration. Diminazene also caused a significant reduction in aminotransferase levels. Comparatively, diminazene treatment was more effective in chronic infection than in early infection. In tandem, our study revealed that diminazene possesses anthelmintic properties and inhibits liver injury caused by Schistosoma eggs.


Assuntos
Parasitos , Esquistossomose mansoni , Esquistossomose , Animais , Diminazena/análogos & derivados , Diminazena/farmacologia , Camundongos , Schistosoma mansoni , Esquistossomose mansoni/tratamento farmacológico
5.
AJR Am J Roentgenol ; 212(2): 467-474, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30476460

RESUMO

OBJECTIVE: The purpose of this study was to assess the feasibility of performing abdominopelvic aortoiliac CT angiography (CTA) with 16.0 g of iodine contrast medium acquired with low-energy (40 and 50 keV) virtual monochromatic (VMC) images with rapid-kilovoltage-switching dual-energy CT. SUBJECTS AND METHODS: A total of 52 adults with abdominal aortoiliac aneurysm and prior 120-kVp single-energy CTA (SECTA) with 33 g iodine (standard dose) underwent follow-up dual-energy CTA (DECTA) with a 52% reduced iodine dose. Subjects were randomly assigned to a contrast medium protocol for DECTA examinations: one group (n = 26) received 16.2 g (270 mg I/mL) and the other (n = 26) received 16.0 g (320 mg I/mL). Two readers independently assessed SECTA and VMC DECTA datasets for image quality using a 5-point scale. Aortoiliac intravascular attenuation was measured, and ANOVA was used to compare measurements between VMC DECTA and SECTA images. In a subset of patients with DECTA after endovascular aortic repair, endoleak detection was evaluated on VMC images. Volume CT dose index, dose-length product, and size-specific dose estimate were compared between DECTA and SECTA. RESULTS: All DECTA examinations (n = 52) were rated diagnostic with image quality scores comparable to those of 120-kVp single-energy CTA (40 keV, 4.2-4.4; 50 keV, 4.6-4.8; SECTA, 4.4-4.5). Intravascular attenuation was uniform in all reduced-iodine DECTA examinations and was significantly higher on 40- and 50-keV images than on standard-iodine-dose SECTA images (720 ± 125 HU and 482 ± 82 HU vs 303 ± 65 HU) (p < 0.01). There was no difference in intravascular attenuation between the 16.2-g and the 16.0-g doses (p = 0.82). Sensitivity and specificity for endoleak detection were 78.9-94.7% and 100%. Total dose-length product was lower for DECTA (788 ± 166 mGy · cm) than for SECTA (1114 ± 468 mGy · cm). CONCLUSION: Low-energy VMC DECTA images (40 and 50 keV) acquired with two contrast protocols at approximately 50% reduced iodine dose (16.0 and 16.2 g) provide adequate intravascular attenuation and diagnostic quality for aortoiliac evaluation.


Assuntos
Aorta Abdominal/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Meios de Contraste/administração & dosagem , Artéria Ilíaca/diagnóstico por imagem , Compostos de Iodo/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Imagem Radiográfica a Partir de Emissão de Duplo Fóton
6.
Indian J Microbiol ; 59(3): 328-335, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31388210

RESUMO

Among the cultivated mushroom, the genus Pleurotus is the second largest produced worldwide and the most produced in Brazil. The application of agricultural by-products (wastes) as substrate supplement is an effective approach to generate quality food while promoting a circular economy in agriculture. The manuscript evaluates the three key aspects of this practice: (1) the response of different mushroom strains to supplementation, (2) the use of agricultural by-products with different N content, and (3) the efficacy of certain preliminary treatments applied to the supplements. To this end, production and nutritional quality of the mushroom were tested along the crop cycle. Compared to the control substrate, the yield increased by 11, 26, 30 and 42% in the first flush and by 86 and 31% in the second flush. Supplementation resulted in an increment of the fiber and protein content of mushroom and a decline of carbohydrate and lipid content of mushroom.

7.
Regul Toxicol Pharmacol ; 92: 338-346, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29258925

RESUMO

ß-caryophyllene is a food additive that is found in food plants and has broad pharmacological potential. However, little toxicological information has been reported and its use is based on the fact that this bicyclic sesquiterpene is daily consumed as a plant food in much larger quantities than as a food additive. Thus, this study evaluated acute (14-day) and repeated-dose (28 days) oral ß-caryophyllene toxicity in female Swiss mice analyzing changes in body weight, food intake, water intake, hematological and biochemical parameters, organ weight after necropsy, oxidative stress markers and histopathology of various tissues. Acute (300 and 2000 mg/kg) and repeated-dose (300 and 2000 mg/kg) toxicity studies were performed according to the Organization for Economic Cooperation and Development (OECD) guideline 423 and 407, respectively. There was absence of adverse clinical signs and mortality in any animal subjected to acute and repeated-dose toxicity study. In addition, no significant changes in body weight, food and water intake, oxidative stress biomarkers, hematological and biochemical parameters were observed when compared to control group from single-dose and repeated-dose toxicity study. Therefore, the results of this study provide an understanding of the toxicity profile of ß-caryophyllene which can be considered a compound with toxicity at doses higher than 2000 mg/kg body weight.


Assuntos
Canabinoides/efeitos adversos , Sesquiterpenos/efeitos adversos , Animais , Peso Corporal/efeitos dos fármacos , Dieta , Relação Dose-Resposta a Droga , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Aditivos Alimentares/efeitos adversos , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/efeitos adversos , Sesquiterpenos Policíclicos , Testes de Toxicidade Aguda/métodos
8.
Regul Toxicol Pharmacol ; 94: 75-82, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29339246

RESUMO

Neoflavonoids, which are classified as 4-arylcoumarin (neoflavone), 3,4-dihydro-4-arylcoumarin and neoflavene, have been the subject of a number of studies with respect to their therapeutic potential and, despite promising in vitro, ex vivo and in vivo pharmacological activities, there is a lack of studies demonstrating their toxicological properties. Therefore, this study aims to evaluate the acute (14 days) and repeated-dose (28 days) toxicity of synthetic neoflavonoid 7-acetoxy-4-aryl-3,4-dihydrocoumarin in Swiss mice through parameters related to changes in body weight, food and water intake, hematological and biochemical parameters. Toxicity studies using acute doses (300 and 2000 mg/kg) and repeated doses (250, 500 and 1000 mg/kg) orally were carried out as per Organization for Economic Co-operation and Development (OECD) guidelines 423 and 407, respectively. Based on the results of this study, treatment with 7-acetoxy-4-aryl-3,4-dihydrocoumarin was found to not cause clinical adverse symptoms and mortality in any animal used in the acute and repeated-dose toxicity study. In addition, no significant changes were observed in body weight and internal organs, food and water intake, hematological and biochemical parameters, compared to control group. Therefore, these results provide an initial understanding regarding the toxicity profile of 7-acetoxy-4-aryl-3,4-dihydrocoumarin, which can be considered a neoflavonoid with toxicity seen at doses higher than 2000 mg/kg in Swiss mice.


Assuntos
Cumarínicos/toxicidade , Animais , Artemia/efeitos dos fármacos , Feminino , Masculino , Camundongos , Testes de Toxicidade Aguda , Testes de Toxicidade Subaguda
9.
Br J Haematol ; 176(4): 583-590, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28055107

RESUMO

Fenretinide, a synthetic retinoid, induces apoptotic cell death in B-cell non-Hodgkin lymphoma (B-NHL) and acts synergistically with rituximab in preclinical models. We report results from a phase I-II study of fenretinide with rituximab for B-NHLs. Eligible diagnoses included indolent B-NHL or mantle cell lymphoma. The phase I design de-escalated from fenretinide at 900 mg/m2 PO BID for days 1-5 of a 7-day cycle. The phase II portion added 375 mg/m2 IV rituximab weekly on weeks 5-9 then every 3 months. Fenretinide was continued until progression or intolerance. Thirty-two patients were treated: 7 in phase I, and 25 in phase II of the trial. No dose-limiting toxicities were observed. The phase II component utilized fenretinide 900 mg/m2 twice daily with rituximab. The most common treatment-related adverse events of grade 3 or higher were rash (n = 3) and neutropenia (n = 3). Responses were seen in 6 (24%) patients on the phase II study, with a median duration of response of 47 months (95% confidence interval, 2-56). The combination of fenretinide and rituximab was well tolerated, yielded a modest overall response rate, but with prolonged remission durations. Further study should focus on identifying the responsive subset of B-NHL.


Assuntos
Fenretinida/administração & dosagem , Linfoma de Células B/tratamento farmacológico , Linfoma de Célula do Manto/tratamento farmacológico , Rituximab/administração & dosagem , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Sinergismo Farmacológico , Exantema/induzido quimicamente , Feminino , Humanos , Linfoma de Células B/complicações , Linfoma de Célula do Manto/complicações , Masculino , Pessoa de Meia-Idade , Neutropenia/induzido quimicamente , Indução de Remissão
10.
AJR Am J Roentgenol ; 207(6): W125-W132, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27610820

RESUMO

OBJECTIVE: The purpose of this study was to compare the image quality of reduced-iodine-dose single-source dual-energy CT angiography (CTA) with that of standard-iodine-dose single-energy CTA in examinations of patients with abdominal aortic aneurysm and to assess the effect of the concentration of iodinated contrast medium on intravascular enhancement and image quality of reduced-iodine-dose CTA. SUBJECTS AND METHODS: In a prospective randomized clinical trial, 66 consecutively registered patients with abdominal aortic aneurysm who had previously undergone single-energy CTA (30-37 g I) underwent follow-up CTA at a reduced dose (21-27 g I) of iodinated contrast medium of either 270 mg I/mL (n = 33) or 320 mg I/mL (n = 33). Two readers independently evaluated virtual monochromatic imaging datasets (40-140 keV) and single-energy CTA images for image quality and noise and their preference for optimal energy virtual monochromatic imaging dataset. A value of p < 0.05 was considered statistically significant. RESULTS: All 66 dual-energy CTA examinations were rated diagnostic with mean image quality and image noise scores of 4.8 and 4.5 for reader 1 and 3.8 and 3.4 for reader 2 compared with single-energy CTA results of 4.5 and 4.2 for reader 1 and 4.5 and 4.1 for reader 2. Low-energy virtual monochromatic images (40-60 keV) from reduced-iodine-dose (28%) dual-energy CTA had significantly higher intravascular aortic attenuation (26-185%) and contrast-to-noise ratio (CNR) (20-25%) than standard-iodine-dose single-energy CTA images (p < 0.0001). No significant difference was found between patients who received 270 and those who received 320 mg I/mL with respect to intravascular aortic attenuation (p = 0.6331) or CNR (p = 0.9775). CONCLUSION: Low-energy virtual monochromatic imaging datasets from reduced-iodine (24 g I) single-source dual-energy CTA of the abdomen provide up to 185% higher attenuation and 25% higher CNR than standard-iodine-dose (33.3 g I) single-energy CTA while offering a wide range of energy settings irrespective of the concentration of IV contrast medium used.


Assuntos
Aneurisma da Aorta Abdominal/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Iodo/administração & dosagem , Exposição à Radiação/análise , Proteção Radiológica/métodos , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Idoso , Idoso de 80 Anos ou mais , Aortografia/métodos , Meios de Contraste , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Exposição à Radiação/prevenção & controle , Intensificação de Imagem Radiográfica/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Interface Usuário-Computador
11.
Pharmacol Res ; 102: 138-57, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26470648

RESUMO

Diminazene aceturate (C14H15N7.2C4H7NO3) is an aromatic diamidine that was developed more than six decades ago and has been marketed until today for the control of trypanosomiasis. In recent years, however, this trypanocidal compound has been extensively studied with respect to its therapeutic potential and has consequently attracted much interest for the development of further research. The objective of this study was to conduct a systematic review on diminazene aceturate regarding its pharmacological properties. In this way, databases were searched for articles (ScienceDirect, Scopus, PubMed, Web of Science and SciFinder) and patents (INPI, USPTO, WIPO, DPMA, SIPO, DERWENT, CIPO and EPO). For the development of this review, 115 articles and 22 patents were selected and analyzed. It was thus possible to highlight several researches that have investigated alternatives in order to improve success in the treatment of animal trypanosomiasis, by using new drugs in associations with diminazene aceturate, as well as looking for new pharmacological applications for this compound, such as leishmanicidal, amebicidal, anti-pneumocystis, anti-rheumatoid arthritis, antihypertensive agent, and mainly as an activator of angiotensin-converting enzyme 2. Another pharmacological property still little studied is the inhibition of acid-sensitive ion channels (ASIC1a, ASIC1b, ASIC2a and ASIC3), which are related to the development of various diseases. Collectively, these studies conducted by several research groups extend the use of diminazene aceturate beyond the antitrypanosomal activity and suggest promising new applications.


Assuntos
Antiparasitários/farmacologia , Antiparasitários/uso terapêutico , Diminazena/análogos & derivados , Tripanossomíase/tratamento farmacológico , Animais , Diminazena/farmacologia , Diminazena/uso terapêutico , Humanos
12.
Curr Cardiol Rep ; 17(10): 87, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26285590

RESUMO

Peripheral artery disease (PAD) has become increasingly common in the US patient population and can be a highly symptomatic and significant source of morbidity. When PAD is suspected, the first-line screening study that is obtained is typically a noninvasive evaluation that includes the ankle brachial index (ABI). Following a positive screening study, invasive catheter digital subtraction angiography (DSA) has been historically used to image the peripheral artery system and still remains the gold standard. However, newer developments in axial imaging including computed tomography angiography (CTA) and magnetic resonance angiography (MRA) have in large part supplanted DSA for imaging the peripheral artery system in clinical practice. Benefits of CTA include rapid noninvasive acquisition, wide availability, high spatial resolution, and the ability to generate isotropic datasets on 64-detector row and higher CT scanners, thereby allowing for multiplanar 3D reformatting. Drawbacks of CTA include the exposure to both iodinated contrast and ionizing radiation, although the radiation dose exposure is lower than for DSA, and newer techniques such as using low tube voltage and rapid acquisition times allow for lower contrast doses. The presence of vascular calcification also limits the evaluation of small distal arteries using CTA, although the development of dual-energy CT techniques has significantly addressed this issue. Benefits of MRA include the avoidance of exposure to ionizing radiation and high diagnostic accuracy, while drawbacks include limited availability and increased cost along with the risk of nephrogenic systemic fibrosis that is associated with gadolinium-based contrast agents, although the latter can be mitigated by using newer non-contrast MR angiography techniques. Future technical advances in CT and MR hardware and software and MR pulse sequences will likely lead to the broader applicability and increased accuracy of noninvasive axial imaging in the evaluation of patients with peripheral artery disease.


Assuntos
Angiografia Coronária , Doença Arterial Periférica/diagnóstico , Angiografia Coronária/instrumentação , Angiografia Coronária/métodos , Progressão da Doença , Humanos , Imageamento por Ressonância Magnética , Doença Arterial Periférica/patologia , Guias de Prática Clínica como Assunto , Valor Preditivo dos Testes , Tomografia Computadorizada por Raios X
13.
Molecules ; 19(3): 3793-803, 2014 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-24662089

RESUMO

Schistosomiasis is a neglected tropical disease that affects hundreds of millions of people worldwide. Since the treatment of this disease currently relies on a single drug, praziquantel, new and safe schistosomicidal agents are urgently required. Nerolidol, a sesquiterpene present in the essential oils of several plants, is found in many foods and was approved by the U.S. Food and Drug Administration. In this study we analysed the in vitro antiparasitic effect of nerolidol on Schistosoma mansoni adult worms. Nerolidol at concentrations of 31.2 and 62.5 µM reduced the worm motor activity and caused the death of all male and female schistosomes, respectively. In addition, confocal laser scanning microscopy revealed morphological alterations on the tegument of worms such as disintegration, sloughing and erosion of the surface, and a correlation between viability and tegumental damage was observed. In conclusion, nerolidol may be a promising lead compound for the development of antischistosomal natural agents.


Assuntos
Esquistossomicidas/química , Esquistossomicidas/farmacologia , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Terpenos/química , Animais , Microscopia Confocal , Testes de Sensibilidade Parasitária , Schistosoma mansoni/efeitos dos fármacos
14.
ACS Omega ; 9(21): 22777-22793, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38826533

RESUMO

Malaria, caused by Plasmodium protozoa with Plasmodium falciparum as the most virulent species, continues to pose significant health challenges. Despite the availability of effective antimalarial drugs, the emergence of resistance has heightened the urgency for developing novel therapeutic compounds. In this study, we investigated the enoyl-ACP reductase enzyme of P. falciparum (PfENR) as a promising target for antimalarial drug discovery. Through a comprehensive analysis, we conducted a comparative evaluation of two lead compounds, LD1 (CID: 44405336, lead compounds 1) and LD2 (CID: 72703246, lead compounds 2), obtained from the PubChem/NCBI ligand database, to serve as reference molecules in the identification of potential derivatives using virtual screening assays. Among the newly identified candidates, Ligand 1 (LG1) and Ligand 2 (LG2) exhibited intriguing characteristics and underwent further investigation through docking and molecular dynamics simulations. Ligand 1 (LG1) demonstrated interactions similar to LD1, including hydrogen bonding with Asp218, while Ligand 2 (LG2) displayed superior binding energy comparable to LD1 and LD2, despite lacking hydrogen bonding interactions observed in the control compounds triclosan and its derivative 7-(4-chloro-2-hydroxyphenoxy)-4-methyl-2H-chromen-2-one (CHJ). Following computational validation using the MM/GBSA method to estimate binding free energy, commercially acquired LG1 and LG2 ligands were subjected to in vitro testing. Inhibition assays were performed to evaluate their potential as PfENR inhibitors alongside triclosan as a control compound. LG1 exhibited no inhibitory effects, while LG2 demonstrated inhibitory effects like triclosan. In conclusion, this study contributes valuable insights into developing novel antimalarial drugs by identifying LG2 as a potential ligand and employing a comprehensive approach integrating computational and experimental methodologies.

15.
Radiol Cardiothorac Imaging ; 6(2): e230105, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38483247

RESUMO

Immunoglobulin 4 (IgG4)-related disease is a chronic immune-mediated fibroinflammatory disorder. Involvement of the vascular system, including large- and medium-sized vessels, is increasingly recognized. The varied appearances of vascular involvement reflect the sequela of chronic inflammation and fibrosis and can include aortitis and periaortitis with resultant complications such as aneurysm formation and dissection. A diagnosis of IgG4-related large vessel involvement should be considered when there is known or suspected IgG4-related disease elsewhere. Other organs that are typically affected in IgG4-related disease include the lacrimal and salivary glands, thyroid, pancreas, biliary tree, lungs, kidneys, and meninges. Diagnosis typically requires careful correlation with clinical, imaging, serum, and pathologic findings. Patients may be managed with corticosteroid therapy or the anti-CD20 monoclonal antibody, rituximab, if needed. The varied clinical presentations and imaging features of large vessel involvement are discussed herein. Keywords: Vascular, Inflammation, Aorta, IgG4-related Vessel Involvement © RSNA, 2024.


Assuntos
Doença Relacionada a Imunoglobulina G4 , Humanos , Doença Relacionada a Imunoglobulina G4/diagnóstico por imagem , Imunoglobulina G , Imagem Multimodal , Aorta , Inflamação
16.
Br J Haematol ; 161(2): 183-91, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23356514

RESUMO

Given the poor outcomes of relapsed aggressive lymphomas and preclinical data suggesting that ≥2·5 µmol/l concentrations of vorinostat synergize with both etoposide and platinums, we hypothesized that pulse high-dose vorinostat could safely augment the anti-tumour activity of (R)ICE [(rituximab), ifosphamide, carboplatin, etoposide] chemotherapy. We conducted a phase I dose escalation study using a schedule with oral vorinostat ranging from 400 mg/d to 700 mg bid for 5 d in combination with the standard (R)ICE regimen (days 3, 4 and 5). Twenty-nine patients [median age 56 years, median 2 prior therapies, 14 chemoresistant (of 27 evaluable), 2 prior transplants] were enrolled and treated. The maximally tolerated vorinostat dose was defined as 500 mg twice daily × 5 d. Common dose limiting toxicities included infection (n = 2), hypokalaemia (n = 2), and transaminitis (n = 2). Grade 3 related gastrointestinal toxicity was seen in 9 patients. The median vorinostat concentration on day 3 was 4·5 µmol/l (range 4·2-6·0 µmol/l) and in vitro data confirmed the augmented antitumour and histone acetylation activity at these levels. Responses were observed in 19 of 27 evaluable patients (70%) including 8 complete response/unconfirmed complete response. High-dose vorinostat can be delivered safely with (R)ICE, achieves potentially synergistic drug levels, and warrants further study, although adequate gastrointestinal prophylaxis is warranted.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Linfoma/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais Murinos/administração & dosagem , Anticorpos Monoclonais Murinos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/administração & dosagem , Carboplatina/efeitos adversos , Sinergismo Farmacológico , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Feminino , Humanos , Ácidos Hidroxâmicos/administração & dosagem , Ácidos Hidroxâmicos/efeitos adversos , Ifosfamida/administração & dosagem , Ifosfamida/efeitos adversos , Masculino , Pessoa de Meia-Idade , Rituximab , Vorinostat
17.
Blood ; 118(4): 1132-9, 2011 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-21508413

RESUMO

Nonmyeloablative allogeneic transplantation (NMAT) infrequently cures active chemoresistant, bulky, or aggressive B-cell lymphoma (B-cell non-Hodgkin lymphoma [B-NHL]). We hypothesized that 9°Y-ibritumomab tiuxetan-based NMAT would facilitate early cytoreduction in such patients promoting improved long-term disease control by the allogeneic graft. Forty high-risk B-NHL patients with persistent disease received 0.4 mCi/kg (maximum, 32 mCi/kg) 9°Y-ibritumomab tiuxetan, fludarabine, and 2 Gy total body irradiation and matched-related (15) or unrelated (25) transplantation. Baseline features included: median age, 58 years (range, 29-69 years); median prior regimens, 6 (range, 3-12); chemosensitive disease, 6 (15%); bulk > 5 cm, 17 (range, 5.2-18.6 cm, 43%); diffuse large B-cell lymphoma, 14 (35%); and comorbidity score > zero, 34 (85%). Early responses were observed in 24 (60%, 14 complete remission/complete remission unconfirmed, 10 partial response) patients, including 17 of 29 (59%) with chemotherapy-resistant disease and 10 (59%) with bulk > 5 cm. The estimated 30-month survival, progression-free survival, and nonrelapse mortality were 54.1%, 31.1%, and 15.9%, respectively. Early response, baseline platelet counts over 25 000/µL, indolent histology, and related donors were associated with improved survival. The addition of 9°Y-ibritumomab tiuxetan to NMAT is safe and yields early responses and prolonged disease control in some of the highest-risk B-NHL patients. This trial was registered at www.clinicaltrials.gov as #NCT00119392.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma de Células B/terapia , Condicionamento Pré-Transplante/métodos , Vidarabina/análogos & derivados , Adulto , Idoso , Transplante de Medula Óssea/métodos , Humanos , Pessoa de Meia-Idade , Radioimunoterapia/métodos , Transplante Homólogo , Vidarabina/administração & dosagem
18.
Pharmacol Biochem Behav ; 232: 173654, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37802395

RESUMO

In the search for anxiolytic drugs with fewer adverse effects, calcium blockers were proposed as a benzodiazepines (BZDs) alternative. In this context, the anxiolytic effect of nimodipine has been demonstrated. However, its low bioavailability and solubility could be improved by using nanostructured drug delivery systems such as liposomes. In this way, liposomal formulation containing nimodipine (NMD-Lipo) was developed. The NMD-lipo is a formulation capable of improving the kinetic characteristics of the drug, as well as the anxiolytic effect of nimodipine. In this work, the serotonergic system participation in the anxiolytic mechanism of the liposomal formulation containing nimodipine (NMD-Lipo) was investigated. A possible 5-HT1A receptor mediation on the NMD-Lipo anxiolytic effect was demonstrated by using WAY 100635 (5-HT1A receptor antagonist) since the antagonist reversed the NMD-Lipo anxiolytic effect in the light/dark test and elevated plus maze test. The results demonstrated that the NMD-Lipo administration had anxiolytic activity through 5-HT1A receptors without causing sedation or compromising the motor coordination of the tested animals.

19.
Radiographics ; 32(2): 453-68, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22411942

RESUMO

The clinical manifestations of coronary artery anomalies vary in severity, with some anomalies causing severe symptoms and cardiovascular sequelae and others being benign. Cardiovascular computed tomography (CT) has emerged as the standard of reference for identification and characterization of coronary artery anomalies. Therefore, it is important for the reader of cardiovascular CT images to be thoroughly familiar with the spectrum of coronary artery anomalies. Hemodynamically significant anomalies include atresia, origin from the pulmonary artery, interarterial course, and congenital fistula. Non-hemodynamically significant anomalies include duplication; high origin; a prepulmonic, transseptal, or retroaortic course; shepherd's crook right coronary artery; and systemic termination. In general, coronary arteries with an interarterial course are associated with an increased risk of sudden cardiac death. Coronary artery anomalies that result in shunting, including congenital fistula and origin from the pulmonary artery, are also commonly symptomatic and may cause steal of blood from the myocardium. Radiologists should be familiar with each specific variant and its specific constellation of potential implications.


Assuntos
Angiografia Coronária/métodos , Anomalias dos Vasos Coronários/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Fístula Artério-Arterial/congênito , Fístula Artério-Arterial/diagnóstico por imagem , Implante de Prótese Vascular , Anomalias dos Vasos Coronários/classificação , Anomalias dos Vasos Coronários/diagnóstico , Anomalias dos Vasos Coronários/fisiopatologia , Anomalias dos Vasos Coronários/cirurgia , Feminino , Fístula/congênito , Fístula/diagnóstico por imagem , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias/diagnóstico por imagem , Hemodinâmica , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Artéria Pulmonar/anormalidades , Fístula Vascular/congênito , Fístula Vascular/diagnóstico por imagem , Adulto Jovem
20.
Adv Rheumatol ; 62(1): 40, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36333769

RESUMO

BACKGROUND: Despite the criteria already established for the classification of knee osteoarthritis (OA), a radiographic and/or clinical knee OA diagnosis usually occurs in cases of fully manifest or more advanced disease, which can make health promotion, prevention, and functional rehabilitation in more advanced stages of the disease less effective. In addition, radiographic knee OA can generate more financial costs for health services. Therefore, developing and validating screening instruments to assess the probability of development and progression of knee OA would be of great value for both clinical practice and science. OBJECTIVE: To cross-culturally adapt and investigate the measurement properties of the Knee OA Pre-screening Questionnaire Brazilian version. METHODS: A total of 250 individuals of both sexes aged between 35 and 92 years [(mean (standard deviation): 63 (11) years old; 74.1 (15.1) kg; 1.59 (0.09) m; 29.38 (5.44) kg/m2] participated in this study. The cross-cultural adaptation and analyses of the measurement properties of the KOPS Brazilian version included: (1) assessment of conceptual and item equivalence; (2) assessment of semantic equivalence; (3) assessment of operational equivalence; and (4) assessment of measurement equivalence, reliability, and validity. RESULTS: Cronbach's alpha for the internal consistency among the six components of the KOPS Brazilian version was 0.71. The test-retest 72 h apart for each component resulted in a coefficient correlation intraclass ranging from 0.74 to 1.00. The probability of an individual randomly chosen from the population having KL ≥ 1 and KOPS Brazilian version ≥ 21 points was 0.74 (area under the curve of the Receiver Operating Characteristic - AUC of ROC); furthermore, the AUC for KL ≥ 2 and the KOPS Brazilian version ≥ 23 points was 0.77. CONCLUSION: The KOPS Brazilian version is a reliable and valid instrument for early screening of knee OA in individuals aged 35 years and over in the Brazilian context.


Assuntos
Osteoartrite do Joelho , Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Criança , Brasil , Osteoartrite do Joelho/diagnóstico por imagem , Reprodutibilidade dos Testes , Comparação Transcultural , Inquéritos e Questionários
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