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3.
Cochrane Database Syst Rev ; 5: CD011368, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32356369

RESUMO

BACKGROUND: Acne is an inflammatory disorder with a high global burden. It is common in adolescents and primarily affects sebaceous gland-rich areas. The clinical benefit of the topical acne treatments azelaic acid, salicylic acid, nicotinamide, sulphur, zinc, and alpha-hydroxy acid is unclear. OBJECTIVES: To assess the effects of topical treatments (azelaic acid, salicylic acid, nicotinamide, zinc, alpha-hydroxy acid, and sulphur) for acne. SEARCH METHODS: We searched the following databases up to May 2019: the Cochrane Skin Group Specialised Register, CENTRAL, MEDLINE, Embase, and LILACS. We also searched five trials registers. SELECTION CRITERIA: Clinical randomised controlled trials of the six topical treatments compared with other topical treatments, placebo, or no treatment in people with acne. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. Key outcomes included participants' global self-assessment of acne improvement (PGA), withdrawal for any reason, minor adverse events (assessed as total number of participants who experienced at least one minor adverse event), and quality of life. MAIN RESULTS: We included 49 trials (3880 reported participants) set in clinics, hospitals, research centres, and university settings in Europe, Asia, and the USA. The vast majority of participants had mild to moderate acne, were aged between 12 to 30 years (range: 10 to 45 years), and were female. Treatment lasted over eight weeks in 59% of the studies. Study duration ranged from three months to three years. We assessed 26 studies as being at high risk of bias in at least one domain, but most domains were at low or unclear risk of bias. We grouped outcome assessment into short-term (less than or equal to 4 weeks), medium-term (from 5 to 8 weeks), and long-term treatment (more than 8 weeks). The following results were measured at the end of treatment, which was mainly long-term for the PGA outcome and mixed length (medium-term mainly) for minor adverse events. Azelaic acid In terms of treatment response (PGA), azelaic acid is probably less effective than benzoyl peroxide (risk ratio (RR) 0.82, 95% confidence interval (CI) 0.72 to 0.95; 1 study, 351 participants), but there is probably little or no difference when comparing azelaic acid to tretinoin (RR 0.94, 95% CI 0.78 to 1.14; 1 study, 289 participants) (both moderate-quality evidence). There may be little or no difference in PGA when comparing azelaic acid to clindamycin (RR 1.13, 95% CI 0.92 to 1.38; 1 study, 229 participants; low-quality evidence), but we are uncertain whether there is a difference between azelaic acid and adapalene (1 study, 55 participants; very low-quality evidence). Low-quality evidence indicates there may be no differences in rates of withdrawal for any reason when comparing azelaic acid with benzoyl peroxide (RR 0.88, 95% CI 0.60 to 1.29; 1 study, 351 participants), clindamycin (RR 1.30, 95% CI 0.48 to 3.56; 2 studies, 329 participants), or tretinoin (RR 0.66, 95% CI 0.29 to 1.47; 2 studies, 309 participants), but we are uncertain whether there is a difference between azelaic acid and adapalene (1 study, 55 participants; very low-quality evidence). In terms of total minor adverse events, we are uncertain if there is a difference between azelaic acid compared to adapalene (1 study; 55 participants) or benzoyl peroxide (1 study, 30 participants) (both very low-quality evidence). There may be no difference when comparing azelaic acid to clindamycin (RR 1.50, 95% CI 0.67 to 3.35; 1 study, 100 participants; low-quality evidence). Total minor adverse events were not reported in the comparison of azelaic acid versus tretinoin, but individual application site reactions were reported, such as scaling. Salicylic acid For PGA, there may be little or no difference between salicylic acid and tretinoin (RR 1.00, 95% CI 0.92 to 1.09; 1 study, 46 participants; low-quality evidence); we are not certain whether there is a difference between salicylic acid and pyruvic acid (1 study, 86 participants; very low-quality evidence); and PGA was not measured in the comparison of salicylic acid versus benzoyl peroxide. There may be no difference between groups in withdrawals when comparing salicylic acid and pyruvic acid (RR 0.89, 95% CI 0.53 to 1.50; 1 study, 86 participants); when salicylic acid was compared to tretinoin, neither group had withdrawals (both based on low-quality evidence (2 studies, 74 participants)). We are uncertain whether there is a difference in withdrawals between salicylic acid and benzoyl peroxide (1 study, 41 participants; very low-quality evidence). For total minor adverse events, we are uncertain if there is any difference between salicylic acid and benzoyl peroxide (1 study, 41 participants) or tretinoin (2 studies, 74 participants) (both very low-quality evidence). This outcome was not reported for salicylic acid versus pyruvic acid, but individual application site reactions were reported, such as scaling and redness. Nicotinamide Four studies evaluated nicotinamide against clindamycin or erythromycin, but none measured PGA. Low-quality evidence showed there may be no difference in withdrawals between nicotinamide and clindamycin (RR 1.12, 95% CI 0.49 to 2.60; 3 studies, 216 participants) or erythromycin (RR 1.40, 95% CI 0.46 to 4.22; 1 study, 158 participants), or in total minor adverse events between nicotinamide and clindamycin (RR 1.20, 95% CI 0.73 to 1.99; 3 studies, 216 participants; low-quality evidence). Total minor adverse events were not reported in the nicotinamide versus erythromycin comparison. Alpha-hydroxy (fruit) acid There may be no difference in PGA when comparing glycolic acid peel to salicylic-mandelic acid peel (RR 1.06, 95% CI 0.88 to 1.26; 1 study, 40 participants; low-quality evidence), and we are uncertain if there is a difference in total minor adverse events due to very low-quality evidence (1 study, 44 participants). Neither group had withdrawals (2 studies, 84 participants; low-quality evidence). AUTHORS' CONCLUSIONS: Compared to benzoyl peroxide, azelaic acid probably leads to a worse treatment response, measured using PGA. When compared to tretinoin, azelaic acid probably makes little or no difference to treatment response. For other comparisons and outcomes the quality of evidence was low or very low. Risk of bias and imprecision limit our confidence in the evidence. We encourage the comparison of more methodologically robust head-to-head trials against commonly used active drugs.


Assuntos
Acne Vulgar/tratamento farmacológico , Fármacos Dermatológicos/uso terapêutico , Adapaleno/efeitos adversos , Adapaleno/uso terapêutico , Adolescente , Adulto , Antibacterianos/uso terapêutico , Peróxido de Benzoíla/uso terapêutico , Viés , Criança , Clindamicina/efeitos adversos , Clindamicina/uso terapêutico , Fármacos Dermatológicos/efeitos adversos , Ácidos Dicarboxílicos/efeitos adversos , Ácidos Dicarboxílicos/uso terapêutico , Eritromicina/efeitos adversos , Eritromicina/uso terapêutico , Feminino , Glicolatos/uso terapêutico , Humanos , Ceratolíticos/uso terapêutico , Masculino , Ácidos Mandélicos/uso terapêutico , Niacinamida/efeitos adversos , Niacinamida/uso terapêutico , Pacientes Desistentes do Tratamento/estatística & dados numéricos , Ácido Pirúvico/efeitos adversos , Ácido Pirúvico/uso terapêutico , Qualidade de Vida , Ácido Salicílico/uso terapêutico , Enxofre/uso terapêutico , Tretinoína/uso terapêutico , Adulto Jovem , Zinco/uso terapêutico
4.
J Biosci Bioeng ; 130(1): 71-75, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32238321

RESUMO

Lignosulfonate is a by-product of the cooking process by sulfite pulping for paper manufacturing. The treatment of wood chips by various salts of sulfurous acid solubilizes lignin to produce a cellulose-rich wood pulp. Developing a technique for the conversion of lignosulfonate by-product to high value materials has an important industrial utility. Sphingobium sp. strain SYK-6, which was isolated from pulping wastewater, is one of the best enzymatically or genetically characterized bacteria for degrading lignin-derived aromatics. We have previously established a system for the production of 2-pyrone-4,6-dicarboxylic acid (PDC), a novel platform chemical that can produce a variety of bio-based polymers, by introducing of ligA, ligB, and ligC genes from SYK-6 into a mutant strain of Pseudomonas putida PpY1100. In this study, extracts from lignosulfonates, which were desulphonated and depolymerized by alkaline oxidation, were evaluated as substrates for microbiological conversion to PDC by the transgenic bacteria.


Assuntos
Lignina/metabolismo , Extratos Vegetais/metabolismo , Pseudomonas putida/metabolismo , Pironas/metabolismo , Sphingomonadaceae/metabolismo , Celulose/metabolismo , Ácidos Dicarboxílicos/metabolismo , Pseudomonas putida/genética , Sphingomonadaceae/genética , Resíduos/análise
6.
PLoS One ; 15(4): e0231765, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32298384

RESUMO

Non-invasive biomarkers will enable widespread screening and early diagnosis of Alzheimer's disease (AD). We hypothesized that the considerable loss of brain tissue in AD will result in detection of brain lipid components in urine, and that these will change in concert with CSF and brain biomarkers of AD. We examined urine dicarboxylic acids (DCA) of carbon length 3-10 to reflect products of oxidative damage and energy generation or balance that may account for changes in brain function in AD. Mean C4-C5 DCAs were lower and mean C7-C10 DCAs were higher in the urine from AD compared to cognitively healthy (CH) individuals. Moreover, mean C4-C5 DCAs were lower and mean C7-C9 were higher in urine from CH individuals with abnormal compared to normal CSF amyloid and Tau levels; i.e., the apparent urine changes in AD also appeared to be present in CH individuals that have CSF risk factors of early AD pathology. In examining the relationship between urine DCAs and AD biomarkers, we found short chain DCAs positively correlated with CSF Aß42, while C7-C10 DCAs negatively correlated with CSF Aß42 and positively correlated with CSF Tau levels. Furthermore, we found a negative correlation of C7-C10 DCAs with hippocampal volume (p < 0.01), which was not found in the occipital volume. Urine measures of DCAs have an 82% ability to predict cognitively healthy participants with normal CSF amyloid/Tau. These data suggest that urine measures of increased lipoxidation and dysfunctional energy balance reflect early AD pathology from brain and CSF biomarkers. Measures of urine DCAs may contribute to personalized healthcare by indicating AD pathology and may be utilized to explore population wellness or monitor the efficacy of therapies in clinical trials.


Assuntos
Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Ácidos Dicarboxílicos/urina , Hipocampo/patologia , Proteínas tau/líquido cefalorraquidiano , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Doenças Assintomáticas , Biomarcadores/líquido cefalorraquidiano , Biomarcadores/urina , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/diagnóstico por imagem , Ácidos Dicarboxílicos/química , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Imagem por Ressonância Magnética , Masculino , Análise Multivariada , Fatores de Risco
9.
Sci Total Environ ; 720: 137449, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32135284

RESUMO

The synergetic effects of benzene-1,4-dicarboxylic acid (BDC) linker structure and the metal cluster of MOFs on adsorption mechanisms of carbamazepine, ciprofloxacin and mefenamic acid were investigated in single and mixed solutions. A 1D flexible framework MIL-53(Al), 3D rigid framework UiO-66(Zr) and 3D flexible framework MIL-88B(Fe) were applied as adsorbents. The breathing effect of MIL-53(Al) caused by its flexible structure can enhance intraparticle diffusion for all pharmaceuticals and perform a critical role in excellent adsorption performances. The 3D rigid BDC structure of UiO-66(Zr) caused a steric effect that reflected low or negligible adsorption. Unless concerning accessibility through the internal structure of the MOFs, the binding strengths calculated by the DFT study were in the following order: MIL-88B(Fe) > MIL-53(Al) > UiO-66(Zr). The Fe cluster in MIL-88B(Fe) seems to have the highest affinity for the carboxylic group of pharmaceuticals compared with Al and Zr; however, the lower porosity of MIL-88B(Fe) might limit the adsorption capacity. Moreover, in mixed solutions, the higher acidity of mefenamic acid can enhance competitive performance in interactions with the metal cation cluster of each MOF. Together with the breathing effect, H-bonding and π-π interaction were shown to be the alternative interactions of synergetic adsorption mechanisms.


Assuntos
Ácidos Dicarboxílicos/química , Adsorção , Benzeno , Carbamazepina , Estruturas Metalorgânicas
10.
Sci Total Environ ; 711: 134822, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31818591

RESUMO

Phthalates are anti-androgenic chemicals and may cause long-lasting adverse effects on growing fetuses. Understanding their exposure profile during pregnancy, therefore, is of public health importance. Because both behavioral and physiological changes of pregnant women are expected to be substantial, the amount of phthalate exposure is expected to vary significantly over the course of pregnancy. Temporal trend of phthalate exposure during pregnancy, however, is largely unknown, especially in Asian women. The purpose of this study is to investigate the urinary concentrations of metabolites for major phthalates and alternative plasticizers over the course of pregnancy among Korean (n = 81) and Thai women (n = 102). Twenty-four metabolites from 15 plasticizers, such as dimethyl phthalate (DMP), diethyl phthalate (DEP), di-isobutyl phthalate (DiBP), di-n-butyl phthalate (DnBP), benzyl butyl phthalate (BBzP), di(2-ethylhexyl) phthalate (DEHP), dioctyl phthalate (DnOP), diisononyl phthalate (DiNP), diisodecyl phthalate (DiDP), di(2-ethylhexyl) terephthalate (DEHTP), and di-(iso-nonyl)-cyclohexane-1,2-dicarboxylate (DINCH), were measured in urine samples collected in each trimester from pregnant women. While the levels of several phthalate metabolites were significantly different by trimester among Korean women, those of Thai women were relatively consistent. Urinary metabolites of DEP and DnOP were higher in Thai pregnant women compared to Korean pregnant women. The detection frequencies of the DINCH metabolite were 67.4% and 44.9% among Korean and Thai pregnant women, respectively. However, the ratio of DINCH to DEHP metabolites was significantly higher in Thai women. According to risk assessment, 11.9% of Korean and 5.3% of Thai women were considered at risk due to phthalate exposure, and DEHP, DnBP and DiBP were identified as major risk drivers. Considering the vulnerability of growing fetuses, further studies are warranted to identify major sources of exposure to these plasticizers during pregnancy.


Assuntos
Ácidos Cicloexanocarboxílicos/urina , Ácidos Dicarboxílicos/urina , Ácidos Ftálicos/urina , Exposição Ambiental , Poluentes Ambientais , Feminino , Humanos , Gravidez , República da Coreia , Tailândia
11.
Food Chem ; 310: 125980, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31838371

RESUMO

Cyanidin-3-O-glucoside (C3G) is principal anthocyanin in Chinese bayberry wine and its degradation is main problem with respect to wine color. Effect of five organic acids existing in bayberry wine on C3G oxidation mediated by iron was investigated in model wine. Fe(II) oxidation was found to follow a decreasing order in oxalate > citrate > tartrate > malate model wine whereas it hardly occurred in succinate model wine. The C3G oxidation mediated by iron followed an increasing order in citrate > oxalate > succinate > malate > tartrate model wine. More degradation products were observed in succinate, malate and tartrate model wine than in citrate and oxalate model wine. C3G degradation mediated by Fe(III) was faster than that mediated by Fe(II) in oxalate, succinate, malate, and tartrate model wine, but not in citrate model wine. C3G oxidation mediated by iron is probably not main mechanism of anthocyanin degradation in bayberry wine.


Assuntos
Antocianinas/metabolismo , Ácidos Dicarboxílicos/química , Glucosídeos/metabolismo , Ferro/metabolismo , Myrica , Vinho , Antocianinas/química , Cor , Ácidos Dicarboxílicos/metabolismo , Glucosídeos/química , Ferro/química , Malatos/química , Myrica/química , Myrica/metabolismo , Oxirredução , Ácido Succínico/química , Ácido Succínico/metabolismo , Tartaratos/química , Vinho/análise
12.
Biochim Biophys Acta Proteins Proteom ; 1868(1): 140293, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676448

RESUMO

Furan-2,5-dicarboxylic acid (FDCA) is a building block of biodegradable plastics that can be used to replace those derived from fossil carbon sources. In recent years, much interest has focused on the synthesis of FDCA from the bio-based 5-hydroxymethylfurfural (HMF) through a cascade of enzyme reactions. Aryl-alcohol oxidase (AAO) and 5-hydroxymethylfurfural oxidase (HMFO) are glucose-methanol-choline flavoenzymes that may be used to produce FDCA from HMF through three sequential oxidations, and without the assistance of auxiliary enzymes. Such a challenging process is dependent on the degree of hydration of the original aldehyde groups and of those formed, the rate-limiting step lying in the final oxidation of the intermediate 5-formyl-furancarboxylic acid (FFCA) to FDCA. While HMFO accepts FFCA as a final substrate in the HMF reaction pathway, AAO is virtually incapable of oxidizing it. Here, we have engineered AAO to perform the stepwise oxidation of HMF to FDCA through its structural alignment with HMFO and directed evolution. With a 3-fold enhanced catalytic efficiency for HMF and a 6-fold improvement in overall conversion, this evolved AAO is a promising point of departure for further engineering aimed at generating an efficient biocatalyst to synthesize FDCA from HMF.


Assuntos
Oxirredutases do Álcool/química , Ácidos Dicarboxílicos/química , Furaldeído/análogos & derivados , Furanos/química , Biocatálise , Furaldeído/química , Oxirredução , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética
13.
Molecules ; 25(1)2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31878051

RESUMO

We have synthesized and examined several complexes of lanthanides with diamides of 2,2'-bipyridyl-6,6'-dicarboxylic acid bearing various hetaryl-based side chains for the elucidation of the effect of the heterocycle on the structure and properties of the ligands. The multigram scale methods for the preparation of various N-alkyl-hetaryls and their diamides were developed. The solid state structure of 6-methyl-2-pyridylamide of 2,2'-bipyridyl-6,6'-dicarboxylic acid possesses a flat structure where the conformation is completely different from that previously observed for N-alkylated 2,2'-bipyridyl-6,6'-dicarboxamides and 2,6-pyridinedicarboxamides. The complexes of new ligands were synthesized and NMR and X-Ray studied their structure in solution and solid state. The results demonstrate that complexes possess the same structures both in solid state and in solution. Stability constants of the complexes were less when comparing with dimethyl-substituted diamides, but higher than for unsubstituted dianilide. Contrarily, the extraction ability of 2-pyridyl-diamide is significantly lower than for corresponding anilide. Specific interaction of extractant with solvent molecules, which is not available for electron-sink pyridine amides, can explain this. The luminescence of new Eu complexes was significantly higher than for all previously 2,2'-bipyridyl-6,6'-dicarboxamides and QY reaches 18%. Asymmetry ratios of Eu complexes were 25% higher when compared other complexes with 2,2'-bipyridyl-6,6'-dicarboxamides, which indicates large deviation from the inversion center.


Assuntos
Complexos de Coordenação/química , Ácidos Dicarboxílicos/química , Elementos da Série dos Lantanídeos/química , Conformação Molecular , 2,2'-Dipiridil/química , Európio/química , Ligantes , Luminescência , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Molecular , Piridinas/química
15.
JAMA ; 322(18): 1780-1788, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31714986

RESUMO

Importance: Additional treatment options are needed for patients who do not achieve sufficient reduction in low-density lipoprotein cholesterol (LDL-C) level with available lipid-lowering therapies. Objective: To assess the efficacy of bempedoic acid vs placebo in patients at high cardiovascular risk receiving maximally tolerated lipid-lowering therapy. Design, Setting, and Participants: Phase 3, randomized, double-blind, placebo-controlled clinical trial conducted at 91 clinical sites in North America and Europe from November 2016 to September 2018, with a final date of follow-up of September 22, 2018. A total of 779 patients with atherosclerotic cardiovascular disease, heterozygous familial hypercholesterolemia, or both met randomization criteria, which included LDL-C level 70 mg/dL (1.8 mmol/L) or greater while receiving maximally tolerated lipid-lowering therapy. Interventions: Patients were randomized 2:1 to treatment with bempedoic acid (180 mg) (n = 522) or placebo (n = 257) once daily for 52 weeks. Main Outcomes and Measures: The primary end point was percent change from baseline in LDL-C level at week 12. Secondary measures included changes in levels of lipids, lipoproteins, and biomarkers. Results: Among 779 randomized patients (mean age, 64.3 years; 283 women [36.3%]), 740 (95.0%) completed the trial. At baseline, mean LDL-C level was 120.4 (SD, 37.9) mg/dL. Bempedoic acid lowered LDL-C levels significantly more than placebo at week 12 (-15.1% vs 2.4%, respectively; difference, -17.4% [95% CI, -21.0% to -13.9%]; P < .001). Significant reductions with bempedoic acid vs placebo were observed at week 12 for non-high-density lipoprotein cholesterol (-10.8% vs 2.3%; difference, -13.0% [95% CI, -16.3% to -9.8%]; P < .001), total cholesterol (-9.9% vs 1.3%; difference, -11.2% [95% CI, -13.6% to -8.8%]; P < .001), apolipoprotein B (-9.3% vs 3.7%; difference, -13.0% [95% CI, -16.1% to -9.9%]; P < .001), and high-sensitivity C-reactive protein (median, -18.7% vs -9.4%; difference, -8.7% [asymptotic confidence limits, -17.2% to -0.4%]; P = .04). Common adverse events included nasopharyngitis (5.2% vs 5.1% with bempedoic acid and placebo, respectively), urinary tract infection (5.0% vs 1.9%), and hyperuricemia (4.2% vs 1.9%). Conclusions and Relevance: Among patients at high risk for cardiovascular disease receiving maximally tolerated statins, the addition of bempedoic acid compared with placebo resulted in a significant lowering of LDL-C level over 12 weeks. Further research is needed to assess the durability and clinical effect as well as long-term safety. Trial Registration: ClinicalTrials.gov Identifier: NCT02991118.


Assuntos
Anticolesterolemiantes/uso terapêutico , Aterosclerose/tratamento farmacológico , Ácidos Dicarboxílicos/uso terapêutico , Ácidos Graxos/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hiperlipidemia Familiar Combinada/tratamento farmacológico , Idoso , Anticolesterolemiantes/efeitos adversos , Aterosclerose/sangue , Doenças Cardiovasculares/prevenção & controle , LDL-Colesterol/sangue , Ácidos Dicarboxílicos/efeitos adversos , Método Duplo-Cego , Quimioterapia Combinada , Ácidos Graxos/efeitos adversos , Feminino , Humanos , Hiperlipidemia Familiar Combinada/sangue , Masculino , Pessoa de Meia-Idade
16.
Nat Commun ; 10(1): 5060, 2019 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-31699986

RESUMO

Engineered enzyme cascades offer powerful tools to convert renewable resources into value-added products. Man-made catalysts give access to new-to-nature reactivities that may complement the enzyme's repertoire. Their mutual incompatibility, however, challenges their integration into concurrent chemo-enzymatic cascades. Herein we show that compartmentalization of complex enzyme cascades within E. coli whole cells enables the simultaneous use of a metathesis catalyst, thus allowing the sustainable one-pot production of cycloalkenes from oleic acid. Cycloheptene is produced from oleic acid via a concurrent enzymatic oxidative decarboxylation and ring-closing metathesis. Cyclohexene and cyclopentene are produced from oleic acid via either a six- or eight-step enzyme cascade involving hydration, oxidation, hydrolysis and decarboxylation, followed by ring-closing metathesis. Integration of an upstream hydrolase enables the usage of olive oil as the substrate for the production of cycloalkenes. This work highlights the potential of integrating organometallic catalysis with whole-cell enzyme cascades of high complexity to enable sustainable chemistry.


Assuntos
Biocatálise , Cicloparafinas/síntese química , Ácidos Dicarboxílicos , Escherichia coli , Ácido Oleico , Azeite de Oliva , Cicloexenos/síntese química , Ciclopentanos/síntese química , Descarboxilação , Hidrólise , Compostos Organometálicos , Oxirredução , Biologia Sintética
17.
J Chem Ecol ; 45(10): 838-848, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31677136

RESUMO

Many aquatic organisms detect and avoid damage-released cues from conspecifics, but the chemical basis of such responses, and the effects of prolonged exposure to such cues, remain poorly understood. Injured tadpoles of the cane toad (Rhinella marina) produce chemical cues that induce avoidance by conspecific tadpoles; and chronic exposure to those cues decreases rates of tadpole survival and growth, and reduces body size at metamorphosis. Such effects suggest that we might be able to use the cane toads' alarm cue for biocontrol of invasive populations in Australia. In the present study, we examined behavioral and ecological effects of compounds that are present in cane toad tadpoles and thus, might trigger avoidance of crushed conspecifics. Four chemicals (L-Arg, L-Leu-L-Leu-OH, L-Leu-L-Ile-OH and suberic acid) induced behavioral avoidance in toad tadpoles at some (but not all) dosage levels, so we then exposed toad larvae to these chemicals over the entire period of larval development. Larval survival and size at metamorphosis were decreased by chronic exposure to crushed conspecifics (consistent with earlier studies), but not by exposure to any of the four chemicals. Indeed, L-Arg increased body size at metamorphosis. We conclude that the behavioral response to crushed conspecifics by cane toad tadpoles can be elicited by a variety of chemical cues, but that consistent exposure to these individual chemical cues does not affect tadpole viability or developmental trajectory. The optimal behavioral tactic of a tadpole may be to flee if it encounters even a single chemical cue likely to have come from an injured conspecific (indicative of predation risk), whereas the continuing presence of that single chemical (but no others) provides a less reliable signal of predation risk. Our data are consistent with results from studies on fish, that suggest a role for multiple chemicals in initiating alarm responses to damage-released cues.


Assuntos
Arginina/farmacologia , Aprendizagem da Esquiva/efeitos dos fármacos , Bufo marinus/fisiologia , Caprilatos/farmacologia , Ácidos Dicarboxílicos/farmacologia , Oligopeptídeos/farmacologia , Animais , Tamanho Corporal/efeitos dos fármacos , Bufo marinus/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/fisiologia , Metamorfose Biológica/efeitos dos fármacos , Oligopeptídeos/química
18.
Drugs R D ; 19(4): 351-366, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31621054

RESUMO

INTRODUCTION: The dihydroorotate dehydrogenase (DHODH) inhibitors leflunomide and teriflunomide are immunomodulatory agents approved to treat rheumatoid arthritis (RA) and multiple sclerosis, respectively, and are actively being investigated as therapeutic agents for other immune-related diseases; however, both structurally related compounds have a number of potentially serious adverse effects. Vidofludimus, a new selective second-generation DHODH inhibitor, is chemically distinct from leflunomide/teriflunomide and appears to exhibit a distinct safety profile. OBJECTIVE: The aim of the COMPONENT study was to assess the efficacy, safety, and pharmacokinetics of vidofludimus in the treatment of patients with active RA on a background therapy of methotrexate. This report focuses solely on the safety results of the COMPONENT trial. METHODS: Patients received once-daily oral vidofludimus (N = 122) or placebo (N = 119) along with their standard of care methotrexate treatment for 13 weeks. Efficacy endpoints were assessed. Safety parameters were monitored throughout treatment and at follow-up. Plasma concentrations of vidofludimus were measured. RESULTS: The primary efficacy endpoint, American College of Rheumatology 20 (ACR20) responder rate at 13 weeks, demonstrated numerical superiority in the treatment group compared with placebo; however, it did not reach statistical significance. Nonetheless, the COMPONENT study yielded important safety and pharmacokinetic data that could provide important information regarding the use of vidofludimus in other clinical trials, not only for RA but also for other autoimmune diseases. A safety profile for vidofludimus similar to placebo was obtained in this RA patient population. This includes similar rates of the adverse events of diarrhea, alopecia, neutropenia, and elevated liver enzymes, all of which are known drug-related adverse events reported for leflunomide and teriflunomide. A potential pharmacokinetic interaction between vidofludimus and methotrexate was observed. CONCLUSIONS: Vidofludimus demonstrated a positive safety profile, making it a promising candidate for the treatment of a variety of immune-related diseases. TRIAL REGISTRATIONS: ClinicalTrials.gov identifier: NCT01010581.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Compostos de Bifenilo/uso terapêutico , Ácidos Dicarboxílicos/uso terapêutico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Fatores Imunológicos/uso terapêutico , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/antagonistas & inibidores , Administração Oral , Artrite Reumatoide/enzimologia , Artrite Reumatoide/imunologia , Compostos de Bifenilo/efeitos adversos , Compostos de Bifenilo/sangue , Ácidos Dicarboxílicos/efeitos adversos , Ácidos Dicarboxílicos/sangue , Método Duplo-Cego , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Feminino , Humanos , Fatores Imunológicos/efeitos adversos , Fatores Imunológicos/sangue , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
19.
Environ Res ; 179(Pt A): 108773, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31605871

RESUMO

Plasticizers are compounds added to plastics to modify their physical proprieties. The most well-known class of plasticizers, the phthalates, has been shown to possess antiandrogenic and tumor promoting activities. 1,2-Cyclohexane dicarboxylic acid diisononyl ester (DINCH) was approved for use in food contact containers in 2006 and has been used as a replacement for phthalates in toys and children products. However, we reported previously that the DINCH metabolite MINCH acts on primary rat adipocytes through the peroxisome proliferator activated receptor (PPAR)-α pathway in a manner similar to phthalates. Evidence from our studies, as well as from the current bibliography on DINCH, suggests that the liver might be one of its target organs. In the present study, we collected tissues from dams exposed subacutely and progeny at postnatal day (PND) 3 and 60 exposed in utero to DINCH (1, 10 and 100 mg/kg bw/day). Exposure to DINCH drastically affected liver gene expression in all 3 age groups tested and in particular at the dose of 1 mg/kg bw/day. The PPAR-α pathway along with other metabolic and DNA replication pathways were affected by DINCH. Modifications in PPAR-α and superoxide dismutase (SOD)-1 protein levels were observed in dams at PND21, as well as male progeny at PND3 and 60. No sign of fibrosis or direct liver toxicity was observed after 8 days of stimulus with low doses of DINCH. This study provides evidence that DINCH is not a biologically inert molecule in the rat, and in the liver its actions are mediated, at least in part, by PPAR-α.


Assuntos
Substâncias Perigosas/toxicidade , Fígado/efeitos dos fármacos , PPAR alfa/metabolismo , Plastificantes/toxicidade , Animais , Criança , Ácidos Cicloexanocarboxílicos/toxicidade , Ácidos Dicarboxílicos , Ésteres , Humanos , Masculino , Ratos , Testes de Toxicidade
20.
Int J Mol Sci ; 20(19)2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31581495

RESUMO

Chitosan/dicarboxylic acid (CS/DA) scaffold has been developed as a bone tissue engineering material. This study evaluated a CS/DA scaffold with and without seeded primary human periodontal ligament cells (hPDLCs) in its capacity to regenerate bone in calvarial defects of mice. The osteogenic differentiation of hPDLCs was analyzed by bone nodule formation and gene expression. In vivo bone regeneration was analyzed in mice calvarial defects. Eighteen mice were divided into 3 groups: one group with empty defects, one group with defects with CS/DA scaffold, and a group with defects with CS/DA scaffold and with hPDLCs. After 6 and 12 weeks, new bone formation was assessed using microcomputed tomography (Micro-CT) and histology. CS/DA scaffold significantly promoted in vitro osteoblast-related gene expression (RUNX2, OSX, COL1, ALP, and OPN) by hPDLCs. Micro-CT revealed that CS/DA scaffolds significantly promoted in vivo bone regeneration both after 6 and 12 weeks (p < 0.05). Histological examination confirmed these findings. New bone formation was observed in defects with CS/DA scaffold; being similar with and without hPDLCs. CS/DA scaffolds can be used as a bone regenerative material with good osteoinductive/osteoconductive properties.


Assuntos
Regeneração Óssea , Quitosana , Ácidos Dicarboxílicos , Ligamento Periodontal/citologia , Tecidos Suporte , Animais , Materiais Biocompatíveis/química , Diferenciação Celular , Quitosana/química , Ácidos Dicarboxílicos/química , Regulação da Expressão Gênica , Humanos , Camundongos , Modelos Animais , Osteoblastos/metabolismo , Tecidos Suporte/química
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