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1.
Biomolecules ; 10(8)2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32764519

RESUMO

Lupane-type pentacyclic triterpenes such as betulin and betulinic acid play an important role in the search for new therapies that would be effective in controlling viral infections. The aim of this study was the synthesis and evaluation of in vitro anti-HIV-1 activity for phosphate derivatives of 3-carboxyacylbetulin 3-5 as well as an in silico study of new compounds as potential ligands of the C-terminal domain of the HIV-1 capsid-spacer peptide 1 (CA-CTD-SP1) as a molecular target of HIV-1 maturation inhibitors. In vitro studies showed that 28-diethoxyphosphoryl-3-O-(3',3'-dimethylsuccinyl)betulin (compound 3), the phosphate analog of bevirimat (betulinic acid derivative, HIV-1 maturation inhibitor), has IC50 (half maximal inhibitory concentration) equal to 0.02 µM. Compound 3 inhibits viral replication at a level comparable to bevirimat and is also more selective (selectivity indices = 1250 and 967, respectively). Molecular docking was used to examine the probable interaction between the phosphate derivatives of 3-carboxyacylbetulin and C-terminal domain (CTD) of the HIV-1 capsid (CA)-spacer peptide 1 (SP1) fragment of Gag protein, designated as CTD-SP1. Compared with interactions between bevirimat (BVM) and the protein, an increased number of strong interactions between ligand 3 and the protein, generated by the phosphate group, were observed. These compounds might have the potential to also inhibit SARS-CoV2 proteins, in as far as the intrinsically imprecise docking scores suggest.


Assuntos
Fármacos Anti-HIV/síntese química , Simulação de Acoplamento Molecular , Triterpenos/química , Produtos do Gene gag do Vírus da Imunodeficiência Humana/metabolismo , Fármacos Anti-HIV/farmacologia , Sítios de Ligação , Fosfatos/química , Ligação Proteica , Succinatos/química , Succinatos/farmacologia , Triterpenos/farmacologia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/química
2.
Science ; 369(6502): 450-455, 2020 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-32703879

RESUMO

The guanosine triphosphatase (GTPase) Rab32 coordinates a cell-intrinsic host defense mechanism that restricts the replication of intravacuolar pathogens such as Salmonella Here, we show that this mechanism requires aconitate decarboxylase 1 (IRG1), which synthesizes itaconate, a metabolite with antimicrobial activity. We find that Rab32 interacts with IRG1 on Salmonella infection and facilitates the delivery of itaconate to the Salmonella-containing vacuole. Mice defective in IRG1 rescued the virulence defect of a S. enterica serovar Typhimurium mutant specifically defective in its ability to counter the Rab32 defense mechanism. These studies provide a link between a metabolite produced in the mitochondria after stimulation of innate immune receptors and a cell-autonomous defense mechanism that restricts the replication of an intracellular bacterial pathogen.


Assuntos
Hidroliases/imunologia , Infecções por Salmonella/imunologia , Salmonella enterica , Salmonella typhimurium , Proteínas rab de Ligação ao GTP/imunologia , Animais , Linhagem Celular , Interações Hospedeiro-Patógeno , Humanos , Hidroliases/metabolismo , Camundongos , Infecções por Salmonella/metabolismo , Infecções por Salmonella/microbiologia , Succinatos , Virulência , Proteínas rab de Ligação ao GTP/metabolismo
3.
Lancet ; 396(10244): 129-142, 2020 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-32653056

RESUMO

Stroke is a major cause of death and disability globally. Diagnosis depends on clinical features and brain imaging to differentiate between ischaemic stroke and intracerebral haemorrhage. Non-contrast CT can exclude haemorrhage, but the addition of CT perfusion imaging and angiography allows a positive diagnosis of ischaemic stroke versus mimics and can identify a large vessel occlusion target for endovascular thrombectomy. Management of ischaemic stroke has greatly advanced, with rapid reperfusion by use of intravenous thrombolysis and endovascular thrombectomy shown to reduce disability. These therapies can now be applied in selected patients who present late to medical care if there is imaging evidence of salvageable brain tissue. Both haemostatic agents and surgical interventions are investigational for intracerebral haemorrhage. Prevention of recurrent stroke requires an understanding of the mechanism of stroke to target interventions, such as carotid endarterectomy, anticoagulation for atrial fibrillation, and patent foramen ovale closure. However, interventions such as lowering blood pressure, smoking cessation, and lifestyle optimisation are common to all stroke subtypes.


Assuntos
Encéfalo/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/prevenção & controle , Administração Intravenosa , Idoso , Idoso de 80 Anos ou mais , Amilose/uso terapêutico , Anticoagulantes/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/prevenção & controle , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/fisiopatologia , Isquemia Encefálica/cirurgia , Hemorragia Cerebral/complicações , Hemorragia Cerebral/tratamento farmacológico , Hemorragia Cerebral/fisiopatologia , Hemorragia Cerebral/cirurgia , Angiografia por Tomografia Computadorizada/métodos , Intervenção Médica Precoce/métodos , Endarterectomia das Carótidas/métodos , Procedimentos Endovasculares/métodos , Forame Oval Patente/cirurgia , Humanos , Pessoa de Meia-Idade , Seleção de Pacientes , Imagem de Perfusão/métodos , Polímeros/uso terapêutico , Recidiva , Acidente Vascular Cerebral/epidemiologia , Succinatos/uso terapêutico , Trombectomia/métodos , Terapia Trombolítica/métodos , Tomografia Computadorizada por Raios X/métodos
4.
Khirurgiia (Mosk) ; (6): 76-81, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32573536

RESUMO

OBJECTIVE: To evaluate the effectiveness of preparing a wound for plastic closure of autoskin using a negative pressure apparatus and Reamberin. MATERIAL AND METHODS: . The results of preoperative preparation of 24 patients with chronic wounds of various etiologies were analyzed. Depending on the treatment regimen, the patients were divided into groups: the main one (n=18), the patients of which were divided into subgroups: in IA (n=9) they used NPWT therapy for 5 days, in IB (n=9) it was combined with Reamberin infusions (1.5% intravenously at a rate of 40-60 drops/min, 500 ml, once a day for 5 days). Patients of the comparison group (II, n=6) received standard preparation. In the dynamics of therapy, a morpho-histological study of wound biopsies was carried out with the determination of the area of fibroblasts, the area of the nucleus of fibroblasts, the number of vessels and the determination of their diameter. After autodermoplasty, the survival of the skin flap was determined. RESULTS: It was found that the combined use of NPWT therapy and Reamberin significantly increases the effectiveness of therapy: the greatest effect on fibroblastogenesis was exerted by the inclusion of NPWT therapy in the regimen - an increase of 1.5 times compared with the results of the traditional regimen. The vascularization of the wound surface (increase in the area and diameter of blood vessels) was best influenced by the combined preparation (NPWT-therapy and Reamberin) preparations - an increase of 3.4 times in comparison with the comparison group, which affected the dynamics of the survival of the skin flap: it was 1.3 times higher than in the comparison group (p<0.01). CONCLUSIONS: The results obtained, along with good tolerability of the drug, allows us to recommend the inclusion of Reamberin in the scheme of preoperative preparation of patients with this pathology.


Assuntos
Antioxidantes/administração & dosagem , Meglumina/análogos & derivados , Tratamento de Ferimentos com Pressão Negativa , Transplante de Pele , Succinatos/administração & dosagem , Ferimentos e Lesões/tratamento farmacológico , Ferimentos e Lesões/cirurgia , Doença Crônica , Humanos , Infusões Intravenosas , Meglumina/administração & dosagem , Cuidados Pré-Operatórios , Transplante Autólogo , Cicatrização , Ferimentos e Lesões/etiologia , Ferimentos e Lesões/terapia
5.
Stomatologiia (Mosk) ; 99(2): 45-49, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32441075

RESUMO

THE AIM OF THE STUDY: Was to assess the stability of antioxidative activity of the active compound 2-ethyl-6-methylpiridine-3-ol succinate of toothpastes of the «Mexidol dent¼ line. MATERIALS AND METHODS: The study involved toothpastes of «MEXIDOL dent¼ line: MEXIDOL dent Aktiv MEXIDOL dent Complex, MEXIDOL dent Sensitive, MEXIDOL dent Fito, MEXIDOL dent Teens, MEXIDOL dent Professional White. Features of 2-ethyl-6-methylpiridine-3-ol succinate («MEXIDOL¼) determined the choice of potentiometric titration method for the assessment of the stability of antioxidative activity. RESULTS AND CONCLUSION: The study confirmed the stability of antioxidative activity of the active compound 2-ethyl-6-methylpiridine-3-ol succinate of toothpastes of the «Mexidol dent¼ line during shelf life.


Assuntos
Picolinas , Cremes Dentais , Adolescente , Antioxidantes , Humanos , Succinatos
6.
Artigo em Inglês | MEDLINE | ID: mdl-32361631

RESUMO

Accumulation of Immune Responsive Gene 1(IRG1) in macrophage induced by lipopolysaccharide (LPS) and interferon gamma (IFN-γ) leads to production of itaconate by decarboxylation of cis-aconitate. The biology associated with IRG1 and itaconate is not fully understood. A rapid and sensitive method for measurement of itaconate will benefit the study of IRG1 biology. Multiple HPLC and derivatization methods were tested. An ion pairing LC-MS/MS method using tributylamine/formic acid as ion pairing agents and a HypercarbTM guard column we proposed demonstrated better peak shape and better sensitivity for itaconate. The current protocol allows baseline separation of itaconate, citraconate, and cis-aconitate without derivatization and direct analysis of analytes in 80% methanol/water solution to avoid the dry-down step. It provides the limit of quantitation (LOQ) of 30 pg itaconate on column with a 4.5-minute run time. This method is validated for measurement of itaconate and cis-aconitate in RAW264.7 cell extract and cell media in a 96-well plate format. We applied this method to successfully measure the increase of itaconate and the decrease of cis-aconitate in RAW cell extract and cell media after LPS/IFN-γ treatment.


Assuntos
Ácido Aconítico/análise , Extratos Celulares/análise , Succinatos/análise , Espectrometria de Massas em Tandem/métodos , Animais , Técnicas Biossensoriais , Butilaminas/química , Cromatografia Líquida de Alta Pressão , Formiatos/química , Hidroxilaminas/química , Interferon gama/química , Limite de Detecção , Lipopolissacarídeos/química , Macrófagos/química , Camundongos , Células RAW 264.7 , Sensibilidade e Especificidade
7.
Bioresour Technol ; 308: 123319, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32278999

RESUMO

The ability to produce second-generation itaconic acid by Aspergillus terreus, and the inhibitory effects of hydrolysis by-products on the fermentation were evaluated by cultivation in a synthetic medium containing components usually present in a real hydrolysate broth from lignocellulosic biomasses. The results showed that A. terreus NRRL 1960 can produce itaconic acid and consume xylose completely, but the conversion is less than the fermentation using only glucose. In addition, compared to fermentation of glucose, or even xylose, the mix of both sugars resulted in a lower itaconic acid yield. In the inhibitory test, the final itaconic acid titer was reduced by acetic acid, furfural, and 5-hydroxymethylfurfural concentrations of, respectively, 188, 175, and 700 mg L-1. However, the presence of any amount of acetic acid proved to be detrimental to itaconic acid production. This research sheds some light on doubts about the biorefinery implementation of itaconic acid production.


Assuntos
Aspergillus , Succinatos , Biomassa , Fermentação
8.
BMC Bioinformatics ; 21(Suppl 3): 63, 2020 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-32321437

RESUMO

BACKGROUND: Protein succinylation has recently emerged as an important and common post-translation modification (PTM) that occurs on lysine residues. Succinylation is notable both in its size (e.g., at 100 Da, it is one of the larger chemical PTMs) and in its ability to modify the net charge of the modified lysine residue from + 1 to - 1 at physiological pH. The gross local changes that occur in proteins upon succinylation have been shown to correspond with changes in gene activity and to be perturbed by defects in the citric acid cycle. These observations, together with the fact that succinate is generated as a metabolic intermediate during cellular respiration, have led to suggestions that protein succinylation may play a role in the interaction between cellular metabolism and important cellular functions. For instance, succinylation likely represents an important aspect of genomic regulation and repair and may have important consequences in the etiology of a number of disease states. In this study, we developed DeepSuccinylSite, a novel prediction tool that uses deep learning methodology along with embedding to identify succinylation sites in proteins based on their primary structure. RESULTS: Using an independent test set of experimentally identified succinylation sites, our method achieved efficiency scores of 79%, 68.7% and 0.48 for sensitivity, specificity and MCC respectively, with an area under the receiver operator characteristic (ROC) curve of 0.8. In side-by-side comparisons with previously described succinylation predictors, DeepSuccinylSite represents a significant improvement in overall accuracy for prediction of succinylation sites. CONCLUSION: Together, these results suggest that our method represents a robust and complementary technique for advanced exploration of protein succinylation.


Assuntos
Aprendizado Profundo , Processamento de Proteína Pós-Traducional , Proteínas/metabolismo , Succinatos/metabolismo , Sítios de Ligação , Ciclo do Ácido Cítrico , Lisina/metabolismo , Proteínas/química
9.
Zh Nevrol Psikhiatr Im S S Korsakova ; 120(3. Vyp. 2): 49-53, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32307430

RESUMO

AIM: To evaluate the efficacy of including cytoflavin in rehabilitation measures in the early recovery period of patients with ischemic stroke. MATERIAL AND METHODS: Results of rehabilitation measures of 100 patients (50 women and 50 men, aged 18 to 85 years) in the early recovery period of ischemic stroke were analyzed. Psychological testing included NIHSS, MMSE, Rankin scale, Rivermead mobility index, exercise tolerance test. Depending on the rehabilitation scheme, patients were divided into the main group (n=50), who received a verticalization course and cytoflavin (intravenously, drip 20.0 ml in 250.0 ml 5% glucose for 14 days). The control group (n=50) included patients who received standard treatment. RESULTS AND CONCLUSION: Inclusion of cytoflavin in the rehabilitation scheme for patients with ischemic stroke increased the effectiveness of treatment, which was manifested by a decrease in the severity of neurological disorders assessed with NIHSS by 17.6% in the main group versus 10.8% in the control group (p<0.05) and recovery of cognitive functions assessed with MMSE by 5.8% versus 1.6%, respectively (p<0.05). In addition, there was a positive dynamics in the restoration of blood pressure (by 37.1% in the main group versus 30.6% in the control group (p<0.05)).


Assuntos
Isquemia Encefálica/terapia , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea/efeitos dos fármacos , Isquemia Encefálica/metabolismo , Cognição/efeitos dos fármacos , Combinação de Medicamentos , Feminino , Mononucleotídeo de Flavina/administração & dosagem , Mononucleotídeo de Flavina/farmacologia , Mononucleotídeo de Flavina/uso terapêutico , Humanos , Inosina Difosfato/administração & dosagem , Inosina Difosfato/farmacologia , Inosina Difosfato/uso terapêutico , Masculino , Pessoa de Meia-Idade , Niacinamida/administração & dosagem , Niacinamida/farmacologia , Niacinamida/uso terapêutico , Acidente Vascular Cerebral/metabolismo , Succinatos/administração & dosagem , Succinatos/farmacologia , Succinatos/uso terapêutico , Resultado do Tratamento , Adulto Jovem
10.
Proc Natl Acad Sci U S A ; 117(19): 10286-10293, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32341150

RESUMO

HIV-1 maturation involves conversion of the immature Gag polyprotein lattice, which lines the inner surface of the viral membrane, to the mature capsid protein (CA) lattice, which encloses the viral RNA. Maturation inhibitors such as bevirimat (BVM) bind within six-helix bundles, formed by a segment that spans the junction between the CA and spacer peptide 1 (SP1) subunits of Gag, and interfere with cleavage between CA and SP1 catalyzed by the HIV-1 protease (PR). We report solid-state NMR (ssNMR) measurements on spherical virus-like particles (VLPs), facilitated by segmental isotopic labeling, that provide information about effects of BVM on the structure and dynamics of CA-SP1 junction helices in the immature lattice. Although BVM strongly blocks PR-catalyzed CA-SP1 cleavage in VLPs and blocks conversion of VLPs to tubular CA assemblies, 15N and 13C ssNMR chemical shifts of segmentally labeled VLPs with and without BVM are very similar, indicating that interaction with BVM does not alter the six-helix bundle structure appreciably. Only the 15N chemical shift of A280 (the first residue of SP1) changes significantly, consistent with BVM binding to an internal ring of hydrophobic side chains of L279 residues. Measurements of transverse 15N spin relaxation rates reveal a reduction in the amplitudes and/or timescales of backbone N-H bond motions, corresponding to a rigidification of the six-helix bundles. Overall, our data show that inhibition of HIV-1 maturation by BVM involves changes in structure and dynamics that are surprisingly subtle, but still sufficient to produce a large effect on CA-SP1 cleavage.


Assuntos
Proteínas do Capsídeo/química , HIV-1/efeitos dos fármacos , Fragmentos de Peptídeos/química , Succinatos/farmacologia , Triterpenos/farmacologia , Vírion/efeitos dos fármacos , Replicação Viral , Produtos do Gene gag do Vírus da Imunodeficiência Humana/metabolismo , Fármacos Anti-HIV/farmacologia , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Farmacorresistência Viral , Infecções por HIV/tratamento farmacológico , Infecções por HIV/metabolismo , Infecções por HIV/virologia , HIV-1/genética , HIV-1/metabolismo , Humanos , Modelos Moleculares , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Conformação Proteica , Vírion/genética , Vírion/metabolismo , Montagem de Vírus , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética
11.
Environ Sci Pollut Res Int ; 27(17): 20725-20735, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32246423

RESUMO

Chicoric acid (CA) is a natural antioxidant with promising hepatoprotective activity. We investigated the potential of CA to prevent methotrexate (MTX) hepatotoxicity, pointing to the role of Nrf2/HO-1 signaling and PPARγ. Rats received CA for 15 days and were then injected with MTX at day 16. Blood and tissue samples were collected for analysis at day 19. CA ameliorated liver function markers and mitigated histological alterations in MTX-induced rats. Pre-treatment with CA suppressed reactive oxygen species and lipid peroxidation and enhanced antioxidants in MTX-induced rats. Moreover, CA upregulated hepatic Nrf2, HO-1, NQO-1, and PPARγ, and attenuated inflammation. Consequently, CA inhibited apoptosis by increasing Bcl-2 expression and suppressing Bax, cytochrome c, and caspase-3 in MTX-administered rats. In conclusion, CA prevented oxidative stress, inflammation, and liver injury induced by MTX by activating Nrf2 /HO-1 signaling and PPARγ.


Assuntos
Ácidos Cafeicos , Doença Hepática Induzida por Substâncias e Drogas , Fator 2 Relacionado a NF-E2 , PPAR gama , Animais , Antioxidantes , Inflamação , Fígado , Metotrexato , Estresse Oxidativo/efeitos dos fármacos , PPAR gama/genética , Ratos , Ratos Wistar , Succinatos , Regulação para Cima/efeitos dos fármacos
12.
Artigo em Inglês | MEDLINE | ID: mdl-32223371

RESUMO

Observations made for the analysis of the oil spill dispersant tracer dioctyl sulfosuccinate (DOSS) during LC50 toxicity testing, highlighted a stability issue for this tracer compound in seawater. A liquid chromatography high-resolution quadrupole time-of-flight mass spectrometry (LC/QToF) was used to confirm monooctyl sulfosuccinate (MOSS) as the only significant DOSS breakdown product, and not the related isomer, 4-(2-ethylhexyl) 2-sulfobutanedioate. Combined analysis of DOSS and MOSS was shown to be applicable to monitoring of spill dispersants Corexit® EC9500A, Finasol OSR52, Slickgone NS, and Slickgone EW. The unassisted conversion of DOSS to MOSS occurred in all four oil spill dispersants solubilized in seawater, although differences were noted in the rate of MOSS formation. A marine microcosm study of Corexit EC9500A, the formulation most rapid to form MOSS, provided further evidence of the stoichiometric conversion of DOSS to MOSS under conditions relevant to real world dilbit spill. Results supported combined DOSS and MOSS analysis for the monitoring of spill dispersant in a marine environment, with a significant extension of sample collection time by 10 days or longer in cooler conditions. Implications of the unassisted formation of MOSS and combined DOSS:MOSS analysis are discussed in relation to improving dispersant LC50 toxicity studies.


Assuntos
Ácido Dioctil Sulfossuccínico/toxicidade , Monitoramento Ambiental/métodos , Hidrocarbonetos/toxicidade , Lipídeos/toxicidade , Tensoativos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Cromatografia Líquida , Ácido Dioctil Sulfossuccínico/análise , Hidrocarbonetos/análise , Dose Letal Mediana , Lipídeos/análise , Microbiota/efeitos dos fármacos , Compostos Orgânicos/análise , Compostos Orgânicos/toxicidade , Petróleo/análise , Poluição por Petróleo/análise , Salmão/crescimento & desenvolvimento , Água do Mar/química , Água do Mar/microbiologia , Succinatos/análise , Succinatos/toxicidade , Tensoativos/análise , Testes de Toxicidade , Poluentes Químicos da Água/análise
13.
Chemosphere ; 254: 126724, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32334248

RESUMO

Chelants application can increase the bioavailability of metals, subsequently limiting plant growth and reducing the efficiency of phytoremediation. Plant growth-promoting rhizobacteria (PGPRs) and rhizobium have substantial potential to improve plant growth and plant tolerance to metal stress. We evaluated the effects of co-inoculation with a PGPR strain (Paenibacillus mucilaginosus) and a Cu-resistant rhizobium strain (Sinorhizobium meliloti) on the efficiency of biodegradable chelant (S,S-ethylenediaminedisuccinic acid; EDDS) assisted phytoremediation of a Cu contaminated soil using alfalfa. The highest total Cu extraction by alfalfa was observed in the EDDS-treated soil upon co-inoculation with the PGPR and rhizobium strains, which was 1.2 times higher than that without co-inoculation. Partial least squares path modeling identified plant oxidative damage and soil microbial biomass as the key variables influencing Cu uptake by alfalfa roots. Co-inoculation significantly reduced the oxidative damage to alfalfa by mitigating the accumulation of malondialdehyde and reactive oxygen species, and improving the antioxidation capacity of the plant in the presence of EDDS. EDDS application decreased microbial diversity in the rhizosphere, whereas co-inoculation increased microbial biomass carbon and nitrogen, and microbial community diversity. Increased relative abundances of Actinobacteria and Bacillus and the presence of Firmicutes taxa as potential biomarkers demonstrated that co-inoculation increased soil nutrient content, and improved plant growth. Co-inoculation with PGPR and rhizobium can be useful for altering plant-soil biochemical responses during EDDS-enhanced phytoremediation to alleviate phytotoxicity of heavy metals and improve soil biochemical activities. This study provides an effective strategy for improving phytoremediation efficiency and soil quality during chelant assisted phytoremediation of metal-contaminated soils.


Assuntos
Inoculantes Agrícolas , Biodegradação Ambiental/efeitos dos fármacos , Cobre/metabolismo , Etilenodiaminas/farmacologia , Rizosfera , Poluentes do Solo/metabolismo , Succinatos/farmacologia , Biomassa , Medicago sativa/metabolismo , Microbiota , Desenvolvimento Vegetal , Raízes de Plantas/microbiologia , Rhizobium
14.
Environ Sci Pollut Res Int ; 27(19): 23575-23585, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32297111

RESUMO

Dengue is the most important infectious disease in the world and is a severe public health problem. The chikungunya is an arbovirus, in many cases, increased, which is transmitted by the same transmitter dengue vector, Aedes aegypti. The symptoms of both diseases are similar, and infections can be lethal. Although there is no preventive vaccine against any of the two diseases, therefore, it is extremely important to control the mosquito. The eggs of A. aegypti are very resistant and hatch into larvae, which later give rise to mosquitoes in any container with water. Natural plant extracts have come from active substances with larvicidal activity against A. aegypti. However, they tend to be highly hydrophobic and need some strategy to improve its affinity for water. Because of these factors, this research aims to synthesize and characterize polymeric materials with properties suitable for the release of hydrophobic principles with larvicidal action. The synthesized polymers are poly (butylene succinate) (PBS) and PBS block copolymer with polyethylene glycol (PEG). The synthesized polymers were characterized by nuclear magnetic resonance, thermal analysis simultaneous, differential scanning calorimetry, Fourier transform infrared spectroscopy, and diffraction of X-rays analysis. The analysis results showed that the synthesized materials have chemical composition and properties suitable for use in the controlled release of actives substances. Systems were prepared using the Dendranthema grandiflora extract, which has larvicidal activity was incorporated via fusion to polymers, to evaluate its release in aqueous media. The results proved that higher amounts of PEG in the copolymer chain speed up the delivery of the larvicidal extract. Besides that, the larvicidal extract concentration required to cause death larvae of A. aegypti was achieved from the first minutes of dissolution tests, indicating that the materials developed are promising tool to fight dengue and chikungunya. This new system is a vital tool for eliminating vectors, potentially contributing to saving millions of lives worldwide.


Assuntos
Aedes , Inseticidas , Nanopartículas Metálicas , Alcenos , Animais , Larva , Mosquitos Vetores , Extratos Vegetais , Folhas de Planta , Polímeros , Succinatos
15.
Bioresour Technol ; 307: 123208, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32208342

RESUMO

Itaconic acid (IA) production by fermentation of undetoxified hydrolysate of bamboo residues by Aspergillus terreus was demonstrated. Monosaccharides were obtained by pretreatment and enzymatic hydrolysis of bamboo residues. A. terreus could not grow and synthesize IA in the hydrolysate. The buffer was confirmed to be an inhibitor, and was successfully replaced by deionized water as the suspension, to release equivalent sugar and eliminate the inhibition. Corn steep liquor significantly improved the adaptability of A. terreus to the hydrolysate at 2.0 g/L. The IA titer obtained (19.35 g/L IA) was the highest to be reported for IA production from lignocellulose without detoxification. Simultaneous saccharification and fermentation and fed-batch fermentation increased the titer to 22.43 g/L and 41.54 g/L, respectively. Meanwhile, economic assessment proved that bamboo residues were potential substrates for IA production with economic effectiveness.


Assuntos
Aspergillus , Succinatos , Fermentação
16.
J Oleo Sci ; 69(3): 219-226, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32115547

RESUMO

Microcapsules were constructed with starch sodium octenyl succinate (SSOS), ß-cyclodextrin (ß-CD), and pectin walls and peony seed oil cores. A rheological phenomenon occurred in which the emulsion initially behaved like a shear-thickening fluid and then a shear-thinning fluid within a shear range. The emulsion exhibited good stability under low amplitude stress; however, as amplitude increased the concentration of pectin played an important role in maintaining the stability of the emulsion system. The optimum embedding yield of peony seed oil (92.5%) was achieved with a ratio of 70% SSOS, 22.5% ß-CD, and 7.5% pectin. This ratio produced 4.521 µm particles with the lowest surface-oil content (2.60%) and moisture content (1.76%). The peony seed oil microcapsules were spherical with smooth surfaces and a synchronous thermogravimetric analysis showed they possessed good thermal stability. Encapsulation increased the induction period to 5-7 times that of unencapsulated peony seed oil.


Assuntos
Cápsulas , Emulsões , Paeonia/química , Óleos Vegetais/química , Óleos Vegetais/isolamento & purificação , Sementes/química , Fenômenos Químicos , Amido , Succinatos , Temperatura
17.
Chem Commun (Camb) ; 56(20): 3047-3049, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32048688

RESUMO

A series of aminocarboxylic acid analogues of aspergillomarasmine A (AMA) and ethylenediamine-N,N'-disuccinic acid (EDDS) were chemoenzymatically synthesized via the addition of various mono- and diamine substrates to fumaric acid catalyzed by the enzyme EDDS lyase. Many of these novel AMA and EDDS analogues demonstrate potent inhibition of the bacterial metallo-ß-lactamase NDM-1. Isothermal titration calorimetry assays revealed a strong correlation between the inhibitory potency of the compounds and their ability to bind zinc. Compounds 1a (AMA), 1b (AMB), 5 (EDDS), followed by 1d and 8a, demonstrate the highest synergy with meropenem resensitizing an NDM-1 producing strain of E. coli to this important carbapenem of last resort.


Assuntos
Ácido Aspártico/análogos & derivados , Complexos de Coordenação/farmacologia , Proteínas de Escherichia coli/antagonistas & inibidores , Etilenodiaminas/farmacologia , Succinatos/farmacologia , Zinco/farmacologia , Inibidores de beta-Lactamases/farmacologia , Aminoácidos/química , Aminoácidos/farmacologia , Ácido Aspártico/química , Ácido Aspártico/farmacologia , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Relação Dose-Resposta a Droga , Proteínas de Escherichia coli/metabolismo , Etilenodiaminas/química , Estrutura Molecular , Relação Estrutura-Atividade , Succinatos/química , Zinco/química , Inibidores de beta-Lactamases/síntese química , Inibidores de beta-Lactamases/química , beta-Lactamases/metabolismo
18.
Khirurgiia (Mosk) ; (2): 95-99, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32105263

RESUMO

A 51-year-old severely burned woman had hospitalized at the Clinic of Thermal Injuries of the S.M. Kirov Military Medical Academy with a diagnosis: flame burn in a surface area of 40% (11%)/II-III b degrees of head, neck, trunk, limbs. Inhalation injury of moderate severity. The infusion drug of the combined action reamberin, which has a volemic and antihypoxic effect, had added to the complex antishock therapy. The presented clinical observation demonstrates the favorable course of burn shock: stopping of burn shock 28 hours after injury.


Assuntos
Queimaduras , Meglumina/análogos & derivados , Militares , Choque , Succinatos , Queimaduras/complicações , Feminino , Hidratação , Humanos , Meglumina/uso terapêutico , Pessoa de Meia-Idade , Choque/etiologia , Choque/terapia , Succinatos/uso terapêutico
19.
PLoS One ; 15(2): e0220084, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32074105

RESUMO

Bletilla striata is an endangered traditional Chinese medicinal plant with multiple uses and a slow regeneration rate of its germplasm resources. To evaluate the callus growth kinetics and accumulation of secondary metabolites (SMs), a callus suspension culture was proven to be a valuable approach for acquiring high yields of medicinal compounds. An effective callus suspension culture for obtaining B. striata callus growth and its SMs was achieved with the in vitro induction of calluses from B. striata seeds. The callus growth kinetics and accumulation of SMs were analyzed using a mathematical model. The resulting callus growth kinetic model revealed that the growth curves of B. striata suspension-cultured calluses were sigmoidal, indicating changes in the growth of the suspension-cultured calluses. Improved Murashige and Skoog callus growth medium was the most favorable medium for B. striata callus formation, with the highest callus growth occurring during the stationary phase of the cultivation period. Callus growth acceleration started after 7 days and thereafter gradually decreased until day 24 of the cultivation period and reached its highest at day 36 period in both the dry weight and fresh weight analyses. The coelonin concentration peaked during the exponential growth stage and decreased afterward during the stationary stage of the callus suspension culture. The maximum content of coelonin (approximately 0.3323 mg/g callus dry weight) was observed on the 18th day of the cultivation cycle, while dactylorhin A and militarine reached the highest concentrations at day 24, and p-hydroxybenzyl alcohol at day 39. This investigation also laid a foundation for a multimathematical model to better describe the accumulation variation of SMs. The production of SMs showed great specificity during callus growth and development. This research provided a well-organized way to increase the accumulation and production of SMs during the scaled-up biosynthesis of calluses in B. striata callus suspension cultures.


Assuntos
Calo Ósseo/crescimento & desenvolvimento , Técnicas de Cultura de Células/métodos , Plantas Medicinais/metabolismo , Glucosídeos/análise , Cinética , Modelos Teóricos , Metabolismo Secundário , Sementes/química , Succinatos/análise
20.
Artigo em Inglês | MEDLINE | ID: mdl-31941097

RESUMO

Adding chelating agents is a critical technique of heavy metal activation for enhancing phytoextraction through the formation of soluble metal complexes which will be more readily available for extraction. The preliminary, dynamic, equilibrium activation experiments and speciation analysis of Pb, Cd and Tl in contaminated red soils were used to select six chelates with relatively good activation performance from nine chelates, and the effects of dosage and pH on the heavy metals activation were studied systematically. Results showed that the activation of Pb, Cd and Tl by chelates reached equilibrium within 2 h, and the activation process showed three stages. Under neutral conditions, chelates had better activation performance on Pb- and Cd-contaminated soils. Except for S,S-ethylenediamine disuccinic acid (S,S-EDDS) and citric acid (CA), the maximum equilibrium activation effect (MEAE) of ethylenediaminetetraacetic acid (EDTA), N,N-bis (carboxymethyl) glutamic acid (GLDA), diethylenetriaminepentaacetic acid (DTPA) and aminotriacetic acid (NTA) was over 81%. The MEAE of Tl-contaminated soil was less than 15%. The decreasing order of the dosage of chelating agents corresponding to MEAE for three types of contaminated soils was Pb-, Cd- and Tl-contaminated soil, relating to the forms of heavy metals, the stability constants of metal-chelates and the activation of non-target elements Fe in red soil. Under acidic conditions, the activation efficiencies of chelates decreased to differing degrees in Pb- and Cd-contaminated soils, whereas the activation efficiencies of chelating agents in Tl-contaminated soils were slightly enhanced.


Assuntos
Cádmio/química , Quelantes/química , Chumbo/química , Poluentes do Solo/química , Tálio/química , Biodegradação Ambiental , Ácido Cítrico/química , Ácido Edético/química , Etilenodiaminas/química , Glutamatos/química , Glicina/análogos & derivados , Glicina/química , Ácido Pentético/química , Solo/química , Succinatos/química
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