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1.
Cytokine ; 179: 156621, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38648682

RESUMO

Chagas disease (CD) is caused by the hemoflagellate protozoan Trypanosoma cruzi. The control of the infection depends of the innate and acquired immune response of host. Moreover, CD plays a significant role in the immune response, and, in this context, microalgae can be an interesting alternative due to its immunomodulatory and trypanocidal effects. This study aimed to evaluate, in vitro, immunomodulatory potentials of the aqueous extracts of Chlorella vulgaris and Tetradesmus obliquus. Both microalgae extracts (ME) were obtained by sonication, and the selectivity index (SI) was determined by assays of inhibitory concentration (IC50) in T. cruzi trypomastigotes cells; as well as the cytotoxic concentrations (CC50) in human peripheral mononuclear cells (PBMC). The immune response was evaluated in T. cruzi-infected PBMC using the IC50 value. ME led to inhibition of T. cruzi trypomastigotes after 24 h of treatment, in which the IC50 values were 112.1 µg/ml to C. vulgaris and 15.8 µg ml-1 to T. obliquus. On the other hand, C. vulgaris did not affect the viability of PBMCs in concentrations up to 1000 µg ml-1, while T. obliquus was non-toxic to PBMCs in concentrations up to 253.44 µg ml-1. In addition, T. obliquus displayed a higher SI against T. cruzi (SI = 16.8), when compared with C. vulgaris (SI = 8.9). C. vulgaris decreased the levels of IFN, indicating a reduction of the inflammatory process; while T. obliquus displayed an interesting immunomodulatory effect, since discretely increased the levels of TNF and stimulated the production of the anti-inflammatory cytokine IL-10. This study confirms that ME are effective against T. cruzi trypomastigotes, and may able to control the parasitemia and preventing the progress of CD while regulating the inflammatory process.


Assuntos
Doença de Chagas , Leucócitos Mononucleares , Microalgas , Trypanosoma cruzi , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/imunologia , Humanos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Doença de Chagas/imunologia , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Microalgas/química , Extratos Vegetais/farmacologia , Citocinas/metabolismo
2.
Genetica ; 152(1): 43-49, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38349466

RESUMO

Satellite DNAs (satDNAs) are highly repetitive sequences that occur in virtually all eukaryotic genomes and can undergo rapid copy number and nucleotide sequence variation among relatives. After chromosomal mapping of the satDNA JcSAT1, it was found a large accumulation at subtelomeres of Jatropha curcas (subgenus Curcas), but an absence of these monomers in J. integerrima (subgenus Jatropha). This fact suggests a dynamic scenario for this satellite repeat in Jatropha genomes. Here, we used a multitasking approach (sequence analysis, DNA blotting and chromosomal mapping) to investigate the molecular organization and chromosomal abundance and distribution of JcSAT1 in a broader group of species from the subgenus Jatropha (J. gossypiifolia, J. mollissima, J. podagrica, and J. multifida) in addition to J. curcas, with the aiming of understanding the evolution of this satDNA. Based on the analysis of BAC clone sequences of J. curcas, a large array (~ 30 kb) of 80 homogeneous monomers of JcSAT1 was identified in BAC 23J11. The monomer size was conserved (~ 358 bp) and contained a telomeric motif at the 5' end. PCR amplification coupled with a Southern blot revealed the presence of JcSAT1-like sequences in all species examined. However, a large set of genome copies was identified only in J. curcas, where a ladder-like pattern with multimers of different sizes was observed. In situ hybridization of BAC 23J11 confirmed the subtelomeric pattern for J. curcas, but showed no signals on chromosomes of species from the subgenus Jatropha. Our data indicate that JcSAT1 is a highly homogeneous satDNA that originated from a region near the telomeres and spread throughout the chromosomal subtermini, possibly due to frequent ectopic recombination between these regions. The abundance of JcSAT1 in the genome of J. curcas suggests that an amplification event occurred either at the base of the subgenus Curcas or at least in this species, although the repeat is shared by all species of the genus studied so far.


Assuntos
Euphorbiaceae , Jatropha , Jatropha/genética , Euphorbiaceae/genética , DNA Satélite/genética , Filogenia , Heterocromatina , Telômero/genética
3.
Neurochem Res ; 48(8): 2424-2435, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36995561

RESUMO

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by inattention, hyperactivity, and impulsivity symptoms. Neuroimaging studies have revealed a delayed cortical and subcortical development pattern in children diagnosed with ADHD. This study followed up on the development in vitro of frontal cortical neurons from Spontaneously hypertensive rats (SHR), an ADHD rat model, and Wistar-Kyoto rats (WKY), control strain, over their time in culture, and in response to BDNF treatment at two different days in vitro (DIV). These neurons were also evaluated for synaptic proteins, brain-derived neurotrophic factor (BDNF), and related protein levels. Frontal cortical neurons from the ADHD rat model exhibited shorter dendrites and less dendritic branching over their time in culture. While pro- and mature BDNF levels were not altered, the cAMP-response element-binding (CREB) decreased at 1 DIV and SNAP-25 decreased at 5 DIV. Different from control cultures, exogenous BDNF promoted less dendritic branching in neurons from the ADHD model. Our data revealed that neurons from the ADHD model showed decreased levels of an important transcription factor at the beginning of their development, and their delayed outgrowth and maturation had consequences in the levels of SNAP-25 and may be associated with less response to BDNF. These findings provide an alternative tool for studies on synaptic dysfunctions in ADHD. They may also offer a valuable tool for investigating drug effects and new treatment opportunities.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Fator Neurotrófico Derivado do Encéfalo , Ratos , Animais , Ratos Endogâmicos SHR , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Ratos Endogâmicos WKY , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtorno do Deficit de Atenção com Hiperatividade/metabolismo , Neurônios/metabolismo , Modelos Animais de Doenças
4.
Int J Mol Sci ; 24(3)2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36768789

RESUMO

Dopamine directly acts in the liver and white adipose tissue (WAT) to regulate insulin signaling, glucose uptake, and catabolic activity. Given that dopamine is secreted by the gut and regulates insulin secretion in the pancreas, we aimed to determine its regulation by nutritional cues and its role in regulating glucagon-like peptide 1 (GLP-1) action in WAT. Solutions with different nutrients were administered to Wistar rats and postprandial dopamine levels showed elevations following a mixed meal and glucose intake. In high-fat diet-fed diabetic Goto-Kakizaki rats, sleeve gastrectomy upregulated dopaminergic machinery, showing the role of the gut in dopamine signaling in WAT. Bromocriptine treatment in the same model increased GLP-1R in WAT, showing the role of dopamine in regulating GLP-1R. By contrast, treatment with the GLP-1 receptor agonist Liraglutide had no impact on dopamine receptors. GLP-1 and dopamine crosstalk was shown in rat WAT explants, since dopamine upregulated GLP-1-induced AMPK activity in mesenteric WAT in the presence of the D2R and D3R inhibitor Domperidone. In human WAT, dopamine receptor 1 (D1DR) and GLP-1R expression were correlated. Our results point out a dietary and gut regulation of plasma dopamine, acting in the WAT to regulate GLP-1 action. Together with the known dopamine action in the pancreas, such results may identify new therapeutic opportunities to improve metabolic control in metabolic disorders.


Assuntos
Glucagon , Glucose , Animais , Humanos , Ratos , Tecido Adiposo Branco/metabolismo , Dieta Hiperlipídica , Dopamina , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Glucose/metabolismo , Insulina/metabolismo , Ratos Wistar
5.
J Craniofac Surg ; 33(7): e728-e733, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35275875

RESUMO

BACKGROUND: An attractive smile depends on the proper proportion and arrangement of lip, teeth gingiva scaffold. The ideal smile is the exposure of the entire length of maxillary teeth with 1 mm gingiva. A gingival display exceeding 3 mm is unpleasant and termed ''gummy smile (GS).'' Lip repositioning is a simple surgical procedure intended to minimize the gingival display by removing a strip of mucosa and shortening the vestibular depth. Botulinum toxin injecting overactive muscles with measured quantities results in a reduction of muscle activity, relaxing the lip muscles and decreasing upward pull on the lip. There are some contraindications: patients with short lips and gingival exposures less than 3 mm. PURPOSE: This case report describes the successful management of GS of a young man. CASE REPORT: The procedures were performed and these techniques resulted in shortened vestibule and restricted the muscle pull of the elevator muscles of the lip, reducing gingival display when the patient smiles. Surgical lip repositioning can be a minimally invasive alternative to orthognathic surgery. Botulinum Toxin injections can be a useful adjunct to enhance the esthetics and improve patient satisfaction, being a more conservative and immediate nonsurgical treatment modality available. CONCLUSIONS: In this way, the clinical case report demonstrated that lip repositioning surgery combined to botulinum toxin injections promising outcomes in the GS correction. The effect showed a marked reduction in gingival display at the 4-years follow-up.


Assuntos
Toxinas Botulínicas , Sorriso , Estética Dentária , Gengiva/cirurgia , Humanos , Lábio/cirurgia , Masculino
6.
Prep Biochem Biotechnol ; 52(9): 1069-1077, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35130473

RESUMO

Trichosporon yeasts are widely employed to produce lipids, lipases, and aspartic peptidases, but there are no previous studies on collagenase production. This work aimed to select the best collagenase producing Amazonian Trichosporon strains. Moreover, a 23-full factorial design (FFD) and a 22-central composite design combined with Response Surface Methodology were applied to optimize production and find the best conditions for hydrolysis of type I bovine collagen. Most of the studied strains had some collagenolytic activity, but the selected one achieved the highest value (44.02 U) and a biomass concentration of 2.31 g/L. The best collagenase production conditions were 160 rpm of agitation, pH 5.5 and a substrate concentration of 4.0 g/L. The former experimental design showed that substrate concentration was the only statistically significant factor on both biomass concentration and collagenase activity, while the latter showed simultaneous effects of substrate concentration and pH on collagenolytic activity, which peaked at pH 5.5-6.4 and substrate concentration of 3.0-3.4 g/L. An additional 2³-FFD was finally used to optimize the conditions collagen hydrolysis, and pH 6, 25 °C and a substrate concentration of 7.5 (g/L) ensured the highest hydrolysis degree. This study is the first that describes optimized conditions of collagenase production by Trichosporon strains.


Assuntos
Trichosporon , Animais , Abelhas , Bovinos , Colágeno , Colagenases , Lipídeos , Pólen
7.
Molecules ; 26(11)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199487

RESUMO

Phenolic compounds are thought to be important to prevent neurodegenerative diseases (ND). Parkinson's Disease (PD) is a neurodegenerative disorder known for its typical motor features, the deposition of α-synuclein (αsyn)-positive inclusions in the brain, and for concomitant cellular pathologies that include oxidative stress and neuroinflammation. Neuroprotective activity of fisetin, a dietary flavonoid, was evaluated against main hallmarks of PD in relevant cellular models. At physiologically relevant concentrations, fisetin protected SH-SY5Y cells against oxidative stress overtaken by tert-butyl hydroperoxide (t-BHP) and against methyl-4-phenylpyridinuim (MPP+)-induced toxicity in dopaminergic neurons, the differentiated Lund human Mesencephalic (LUHMES) cells. In this cellular model, fisetin promotes the increase of the levels of dopamine transporter. Remarkably, fisetin reduced the percentage of cells containing αsyn inclusions as well as their size and subcellular localization in a yeast model of αsyn aggregation. Overall, our data show that fisetin exerts modulatory activities toward common cellular pathologies present in PD; remarkably, it modulates αsyn aggregation, supporting the idea that diets rich in this compound may prove beneficial.


Assuntos
Butiratos/efeitos adversos , Flavonóis/farmacologia , Doença de Parkinson/metabolismo , Piperidinas/efeitos adversos , alfa-Sinucleína/metabolismo , Linhagem Celular , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Humanos , Modelos Biológicos , Estresse Oxidativo , Doença de Parkinson/tratamento farmacológico , Agregados Proteicos/efeitos dos fármacos , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , terc-Butil Hidroperóxido/metabolismo
8.
Prep Biochem Biotechnol ; 51(3): 289-299, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32907464

RESUMO

ß-Galactosidase production, partial purification and characterization by a new fungal were investigated. Partial purification was performed by aqueous two-phase system (ATPS) using polyethylene glycol (PEG) molar mass, PEG concentration, citrate concentration and pH as the independent variables. Purification factor (PF), partition coefficient (K) and yield (Y) were the responses. After identification by rDNA sequencing and classification as Cladosporium tenuissimum URM 7803, this isolate achieved a maximum cell concentration and ß-galactosidase activity of 0.48 g/L and 462.1 U/mL, respectively. ß-Galactosidase partitioned preferentially for bottom salt-rich phase likely due to hydrophobicity and volume exclusion effect caused in the top phase by the high PEG concentration and molar mass. The highest value of PF (12.94) was obtained using 24% (w/w) PEG 8000 g/mol and 15% (w/w) citrate, while that of Y (79.76%) using 20% (w/w) PEG 400 g/mol and 25% (w/w) citrate, both at pH 6. The enzyme exhibited optimum temperature in crude and ATPS extracts in the ranges 35-50 °C and 40-55 °C, respectively, and optimum pH in the range 3.0-4.5, with a fall of enzyme activity under alkaline conditions. Some metal ions and detergents inhibited, while others stimulated enzyme activity. Finally, C. tenuissimum URM 7803 ß-galactosidase showed a profile suitable for prebiotics production.


Assuntos
Cladosporium/enzimologia , Polietilenoglicóis/química , beta-Galactosidase/química , Biotecnologia , Citratos , DNA/análise , Detergentes/química , Fermentação , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Íons , Ferro/química , Lactose/química , Microscopia Eletrônica de Varredura , Filogenia , Reação em Cadeia da Polimerase , Prebióticos , Análise de Sequência de DNA , Temperatura , Água/química , beta-Galactosidase/isolamento & purificação
9.
Prep Biochem Biotechnol ; 51(2): 191-200, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32845203

RESUMO

Fibrinolytic enzymes have been considered promising for treatment and protection of healthy circulation due its ability to dissolve the fibrin in blood clots. Extractive fermentation is a not explored and efficient downstream process which segregates the desired product simultaneously in a fermentation process fast and economically. Extraction of fibrinolytic enzymes by Bacillus stearothermophilus DPUA 1729 employing conventional aqueous two-phase systems (ATPS) and extractive fermentation with ATPS was evaluated. The results of both systems were compared using a factorial design with PEG molar mass, PEG and salt concentrations as independent variables and extraction parameters as a response. In all conditions evaluated it was observed a similar partitioning of fibrinolytic enzymes through the phases, both in conventional ATPS and extractive fermentation. Salt concentration and interaction among PEG and salt concentration influenced in the partition coefficient. The fibrinolytic activity was determined by hydrolysis of fibrin in plate using the extract of one condition from extractive fermentation. The zone degradation presented a diameter of 7.03 ± 0.94 mm. In conclusion, there was no significant difference among the results obtained using conventional ATPS and extractive fermentation, however, the second one presents more advantages and can integrate production and extraction in one single step, reducing the costs.


Assuntos
Fermentação , Geobacillus stearothermophilus/metabolismo , Peptídeo Hidrolases/metabolismo , Trombose/enzimologia , Animais , Fibrinólise , Hidrólise , Testes de Sensibilidade Microbiana , Polietilenoglicóis , Ratos , Ratos Wistar , Software , Alimentos de Soja , Sulfatos , Trombose/tratamento farmacológico , Ativador de Plasminogênio Tecidual/química , Ativador de Plasminogênio Tipo Uroquinase/química , Água
10.
Prep Biochem Biotechnol ; 51(2): 164-172, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32795118

RESUMO

Lovastatin is a drug in the statin class which acts as a natural inhibitor of 3-hydroxy-3-methylglutaryl, a coenzyme reductase reported as being a potential therapeutic agent for several diseases: Alzheimer's, multiple sclerosis, osteoporosis and due to its anti-cancer properties. Aspergillus terreus is known for producing a cholesterol reducing drug. This study sets out to evaluate the production of lovastatin by Brazilian wild strains of A. terreus isolated from a biological sample and natural sources. Carbon and nitrogen sources and the best physicochemical conditions using factorial design were also evaluated. The 37 fungal were grown to produce lovastatin by submerged fermentation. A. terreus URM5579 strain was the best lovastatin producer with a level of 13.96 mg/L. Soluble starch and soybean flour were found to be the most suitable substrates for producing lovastatin (41.23 mg/L) and biomass (6.1 mg/mL). The most favorable production conditions were found in run 16 with 60 g/L soluble starch, 15 g/L soybean flour, pH 7.5, 200 rpm and maintaining the solution at 32 °C for 7 days, which led to producing 100.86 mg/L of lovastatin and 17.68 mg/mL of biomass. Using natural strains and economically viable substrates helps to optimize the production of lovastatin and promote its use.


Assuntos
Aspergillus/metabolismo , Biotecnologia/métodos , Lovastatina/biossíntese , Biomassa , Brasil , Carbono , Colesterol/química , Cromatografia Líquida de Alta Pressão , Fermentação , Concentração de Íons de Hidrogênio , Nitrogênio , Glycine max , Espectrofotometria Ultravioleta , Amido/química , Temperatura , Fatores de Tempo
11.
Pharmacol Res ; 161: 105198, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32942016

RESUMO

Methylglyoxal was shown to impair adipose tissue capillarization and insulin sensitivity in obese models. We hypothesized that glyoxalase-1 (GLO-1) activity could be diminished in the adipose tissue of type 2 diabetic obese patients. Moreover, we assessed whether such activity could be increased by GLP-1-based therapies in order to improve adipose tissue capillarization and insulin sensitivity. GLO-1 activity was assessed in visceral adipose tissue of a cohort of obese patients. The role of GLP-1 in modulating GLO-1 was assessed in type 2 diabetic GK rats submitted to sleeve gastrectomy or Liraglutide treatment, in the adipose tissue angiogenesis assay and in the HUVEC cell line. Glyoxalase-1 activity was decreased in visceral adipose tissue of pre-diabetic and diabetic obese patients, together with other markers of adipose tissue dysfunction and correlated with increased HbA1c levels. Decreased adipose tissue GLO-1 levels in GK rats were increased by sleeve gastrectomy and Liraglutide, being associated with overexpression of angiogenic and vasoactive factors, as well as insulin receptor phosphorylation (Tyr1161). Moreover, GLP-1 increased adipose tissue capillarization and HUVEC proliferation in a glyoxalase-dependent manner. Lower adipose tissue GLO-1 activity was observed in dysmetabolic patients, being a target for GLP-1 in improving adipose tissue capillarization and insulin sensitivity.


Assuntos
Tecido Adiposo/irrigação sanguínea , Capilares/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Hipoglicemiantes/farmacologia , Incretinas/farmacologia , Resistência à Insulina , Lactoilglutationa Liase/metabolismo , Liraglutida/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Adulto , Idoso , Animais , Capilares/enzimologia , Capilares/fisiopatologia , Células Cultivadas , Diabetes Mellitus Tipo 2/enzimologia , Diabetes Mellitus Tipo 2/fisiopatologia , Modelos Animais de Doenças , Feminino , Gastrectomia , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/enzimologia , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/enzimologia , Obesidade/fisiopatologia , Obesidade/cirurgia , Ratos Wistar , Transdução de Sinais
12.
J Oral Maxillofac Surg ; 78(2): 184-189, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31604060

RESUMO

PURPOSE: One of the main challenges after extraction of unerupted third molars is pain control, and one of the treatments for pain control is low-level laser therapy (LLLT). Thus, this study aimed to assess the effectiveness of LLLT for pain control after extraction of lower third molars. MATERIALS AND METHODS: This randomized, double-blind, split-mouth study included patients who required bilateral extraction of unerupted lower third molars. Patients received LLLT on 1 side (laser group) but not on the opposite side (control group). On the experimental side, each patient received a laser application at 5 intraoral points for 30 seconds per point. This procedure was simulated on the control side. The pain control response was assessed with a modified pain visual analog scale at the following times: immediately after surgery (T0), after laser application (T1), 24 hours after surgery (T2), 48 hours after surgery (T3), and 72 hours after surgery (T4). RESULTS: Thirty-two patients, 56.25% of whom were women, underwent extraction; the average age was 22.2 years. At the times analyzed, the laser group presented better results than the control group. As for the times, there were differences in pain scores between T0 (8.03 ± 14.87) and T3 (2.66 ± 4.23), as well as T4 (3.36 ± 7.83), in the laser group and differences between T0 (19.76 ± 26.66) and T3 (7.11 ± 10.76), as well as T4 (6.26 ± 13.14), in the control group. CONCLUSION: LLLT was effective in reducing pain after surgical removal of unerupted third molars. At T3 and T4, pain reduction in relation to T0 was noted in both groups.


Assuntos
Terapia com Luz de Baixa Intensidade , Dente Serotino , Adulto , Método Duplo-Cego , Feminino , Humanos , Dor , Manejo da Dor , Dor Pós-Operatória , Extração Dentária , Adulto Jovem
13.
Genet Mol Biol ; 42(4): e20190112, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32059051

RESUMO

Interspecific hybridization is required for the development of Jatropha curcas L. improved cultivars, due to its narrow genetic basis. The present study aimed to analyze the parental genomic composition of F1 and BC1F1 generations derived from interspecific crosses (J. curcas/J. integerrima and J. curcas/J. multifida) by GISH (Genomic In Situ Hybridization), and the meiotic index and pollen viability of F1 hybrids. In F1 cells from both hybrids, 11 chromosomes of each parental was observed, as expected, but chromosome rearrangement events could be detected using rDNA chromosome markers, suggesting unbalanced cells. In the BC1F1, both hybrids had 22 chromosomes, suggesting that only n = 11 gametes were viable in the next generation. However, GISH allowed the identification of three and two alien chromosomes in J. curcas//J. integerrima and J. curcas//J. multifida BC1F1 hybrids, respectively, suggesting a preferential transmission of J. curcas chromosomes for both hybrids. Pollen viability in F1 hybrids derived from J. curcas/J. integerrima crosses were higher (82-83%) than those found for J. curcas/J. multifida (68%), showing post-meiotic problems in these last hybrids, with dyads, triads, polyads, and micronuclei as post-meiosis results. The here presented cytogenetic characterization of interspecific hybrids and their backcross progenies can contribute to the selection of the best genotypes for future assisted breeding of J. curcas.

14.
World J Microbiol Biotechnol ; 36(9): 128, 2020 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-32712871

RESUMO

Bacillus thuringiensis (Bt) is one of the most promising biological control agents used commercially. Its products can contribute to reducing ecological and environmental problems associated with the use of chemical pesticides. Among the limiting factors of using Bt as bioinsecticide are the costs and ensuring its biological activity, which may vary according to the strain and culture conditions. This systematic review aimed to collect state-of-the-art information on the production of Bt endotoxins and to score the methodological feasibility of the data obtained, thus highlighting possible incoherencies. In order to consolidate recent findings and guide future studies, a total of 47 original articles from the last 10 years was analysed, with special attention being given to corroborating data, identifying inconsistencies and suggesting future adjustments so as to increase data reliability. With a maximum score of 8 points, three production parameters were classified on the following scale: preferable (score: 2), adequate (score: 1) and inadequate (score: 0), and another two parameter were classified as adequate (score: 1) or inadequate (score: 0). No article scored more than 6 out of the maximum of 8, thus reflecting the need for more detailed studies regarding Bt endotoxin production. The lack of standardization of methods and units of measurement also have made a comparison of results and an overall analysis difficult. Standards are suggested in the present study. The inclusion of bioassays and quantifying toxin via alkaline dilution are strongly recommended for studies of this nature, along with LC50 expressed in mg/L. Sixteen articles (34%) did not use either of these suggested methods, which indicates the need for further supporting studies. These findings reinforce the need for robust studies in this area, which could include the development of more affordable and effective bioinsecticides, thus increasing their competitiveness against insecticides derived from unsustainable sources.


Assuntos
Toxinas de Bacillus thuringiensis/biossíntese , Bacillus thuringiensis/metabolismo , Endotoxinas/biossíntese , Animais , Toxinas de Bacillus thuringiensis/análise , Bioensaio , Agentes de Controle Biológico , Bases de Dados Factuais , Endotoxinas/análise , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Controle Biológico de Vetores
15.
Mol Biol Rep ; 46(3): 3257-3264, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31073913

RESUMO

The aim of this work was to study the effect of the carbon source (glycerol, sucrose, glucose or a sucrose/glucose mixture) on the production of the anti LDL (-) single-chain variable fragment (scFv) by the recombinant Pichia pastoris SMD 1168 strain as well as on the cell size. The use of glucose as a carbon source in the growth phase led to a remarkable increase in cell size compared with glycerol, while the smallest cells were obtained with sucrose likely due to the occurrence of an energetic stress. The scFv concentration seemed to be related to cell number rather than to cell concentration, which in its turn showed no significant dependence on the carbon source. Yeast cells grown on sucrose had a mean diameter (0.736 ± 0.097 µm) about 35% shorter than those grown on glucose and allowed for the highest final concentration of the scFv antibody fragment (93.7 ± 0.2 mg/L). These results demonstrate that sucrose is the best carbon source for the expression of such an antibody fragment by the recombinant P. pastoris strain, which may be very useful for the diagnostic analysis of the so-called "bad cholesterol".


Assuntos
Carbono/metabolismo , LDL-Colesterol/imunologia , Pichia/metabolismo , Tamanho Celular , Fermentação , Expressão Gênica , Glicerol , Pichia/genética , Proteínas Recombinantes/genética , Anticorpos de Cadeia Única/metabolismo
16.
Prep Biochem Biotechnol ; 49(5): 501-509, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30945982

RESUMO

A new collagenase producing a strain of Bacillus cereus, isolated from the pollen of a bee of Amazon Region (Brazil), had its enzyme characterized and the production medium composition and culture conditions enhanced. A two-level design on three factors, namely initial medium pH, the substrate (gelatin) concentration and agitation intensity, allowed identifying the first two variables as the most significant ones, while a central composite design (CCD) was subsequently used to identify their optimal levels. Statistics highlighted maximized collagenolytic activity when substrate concentration and initial medium pH were selected at their highest levels (positive effects), whereas agitation intensity at the lowest (negative effect). Triplicate runs performed under predicted optimal conditions (pH 7.8 and 1.7% gelatin concentration) yielded a collagenolytic activity (305.39 ± 5.15 U) 4.6- to 15-fold those obtained with the preliminary design. The enzyme displayed optimum activity at 45 °C and pH 7.2, was stable over wide ranges of pH values and temperatures (7.2-11.0 and 25-50 °C, respectively) and was strongly inhibited by 10 mM phenylmethylsulphonyl fluoride. The zymogram showed two prominent bands at 50 and 76 kDa. These results are a first attempt to elucidate the features of this new collagenase, its production conditions, and possible scale-up.


Assuntos
Bacillus cereus/enzimologia , Colagenases/química , Animais , Bacillus cereus/genética , Técnicas de Tipagem Bacteriana , Abelhas , Brasil , Colagenases/isolamento & purificação , Meios de Cultura , Precursores Enzimáticos/química , Precursores Enzimáticos/isolamento & purificação , Gelatina/metabolismo , Concentração de Íons de Hidrogênio , Inibidores de Metaloproteinases de Matriz/química , Pólen/microbiologia , RNA Ribossômico 16S/genética , Temperatura
17.
Biotechnol Appl Biochem ; 65(3): 381-389, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29205941

RESUMO

Viral vectors are important in medical approaches, such as disease prevention and gene therapy, and their production depends on efficient prepurification steps. In the present study, an aqueous two-phase micellar system (ATPMS) was evaluated to extract human adenovirus type 5 particles from a cell lysate. Adenovirus was cultured in human embryonic kidney 293 (HEK-293) cells to a concentration of 1.4 × 1010 particles/mL. Cells were lysed, and the system formed by direct addition of Triton X-114 in a 23 full factorial design with center points. The systems were formed with Triton X-114 at a final concentration of 1.0, 6.0, and 11.0% (w/w), cell lysate pH of 6.0, 6.5, and 7.0, and incubation temperatures at 33, 35, and 37 °C. Adenovirus particles recovered from partition phases were measured by qPCR. The best system condition was with 11.0% (w/w) of Triton X-114, a cell lysate pH of 7.0, and an incubation temperature at 33 °C, yielding 3.51 × 1010 adenovirus particles/mL, which increased the initial adenovirus particles concentration by 2.3-fold, purifying it by 2.2-fold from the cell lysate, and removing cell debris. In conclusion, these results demonstrated that the use of an aqueous two-phase micellar system in the early steps of downstream processing could improve viral particle extraction from cultured cells while integrating clarification, concentration, and prepurification steps.


Assuntos
Adenoviridae/isolamento & purificação , Extratos Celulares/química , Micelas , Água/química , Células Cultivadas , Vetores Genéticos/isolamento & purificação , Células HEK293 , Humanos
18.
Genet Mol Biol ; 41(2): 442-449, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29767665

RESUMO

Jatropha is an important genus of Euphorbiaceae, with species largely used for various purposes, including the manufacturing of soaps and pharmaceutical products and applications in the bioenergetic industry. Although there have been several studies focusing J. curcas in various aspects, the karyotype features of Jatropha species are poorly known. Therefore, we analyzed six Jatropha species through fluorochrome staining (CMA/DAPI), fluorescent in situ hybridization (FISH) with 5S and 45S rDNA probes and genome size estimation by flow cytometry. Our results revealed several chromosome markers by both CMA/DAPI and FISH for the analyzed species. Five Jatropha species (J. curcas, J. gossypiifolia, J. integerrima, J. multifida and J. podagrica) showed four CMA-positive (CMA+) bands associated with the 5S and 45S rDNA sites (one and two pairs, respectively). However, J. mollissima displayed six CMA+/DAPI- bands co-localized with both 5S and 45S rDNA, which showed a FISH superposition. A gradual variation in the genome sizes was observed (2C = 0.64 to 0.86 pg), although an association between evidenced heterochromatin and genome sizes was not found among species. Except for the unique banding pattern of J. mollissima and the pericentromeric heterochromatin of J. curcas and J. podagrica, our data evidenced relatively conserved karyotypes.

19.
Aten Primaria ; 50(6): 340-349, 2018.
Artigo em Espanhol | MEDLINE | ID: mdl-28867157

RESUMO

OBJECTIVE: To determine whether antithrombotic treatment (ATT) in patients with non-valvular atrial fibrillation in a health area complies with the recommendations of current clinical guidelines. DESIGN: Prospective observational study. LOCATION: Primary Health Care Centres and Cardiology Department of a Health Department of the Valencian Community, Spain. PARTICIPANTS: A total of 505 patients with nonvalvular atrial fibrillation were included in the study. MAIN MEASUREMENTS: ATT was deemed to be inappropriate in patients with a CHA2DS2-VASc score ≥1 and who were not under oral anticoagulation, in patients treated with antivitaminK drugs, and poor control of oral anticoagulation, or with antiplatelet therapy inappropriately associated with anticoagulation, and in patients on ATT with a CHA2DS2-VASc score=0. RESULTS: The median age was 77.4±10years. The ATT was considered inadequate in 58% of cases. Factors independently associated with inadequate ATT were age (OR: 1.02 [1-1.04]; P=.029), hypothyroidism (OR: 1.98 [1.14-3.43]; P=.015), ischaemic heart disease (OR: 1.3 [1.15-2.59]; P=.008) and paroxysmal non-valvular AF (OR: 2.11 [1.41-3.17]; P<.0001). CONCLUSIONS: These data underline the high prevalence of inadequate ATT in daily practice, as well its different causes.


Assuntos
Anticoagulantes/uso terapêutico , Fibrilação Atrial/complicações , Fibrinolíticos/uso terapêutico , Fidelidade a Diretrizes , Acidente Vascular Cerebral/prevenção & controle , Idoso , Fibrilação Atrial/epidemiologia , Humanos , Hipotireoidismo/complicações , Isquemia Miocárdica/complicações , Inibidores da Agregação Plaquetária/uso terapêutico , Prevalência , Estudos Prospectivos
20.
Protein Expr Purif ; 133: 8-14, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28242427

RESUMO

Collagenases are proteolytic enzymes capable of degrading both native and denatured collagen, reported to be applied in industrial, medical and biotechnological sectors. Liquid-liquid extraction using aqueous two-phase system (ATPS) is one of the most promising bioseparation techniques, which can substitute difficult solid-liquid separation processes, offering many advantages over conventional methods including low-processing time, low-cost material and low-energy consumption. The collagenase produced by Penicillium sp. UCP 1286 showed a stronger affinity for the bottom salt-rich phase, where the highest levels of collagenolytic activity were observed at the center point runs, using 15.0% (w/w) PEG 3350 g/mol and 12.5% (w/w) phosphate salt at pH 7.0 and concentration. The enzyme was characterized by thermal stability, pH tolerance and effect of inhibitors, showing optimal collagenolytic activity at 37 °C and pH 9.0 and proved to be a serine protease. ATPS showed high efficiency in the collagenase purification, confirmed by a single band in SDS/PAGE, and can in fact be applied as a quick and inexpensive alternative method.


Assuntos
Colagenases/isolamento & purificação , Proteínas Fúngicas/isolamento & purificação , Penicillium/enzimologia , Fosfatos/química , Polietilenoglicóis/química , Colagenases/química , Proteínas Fúngicas/química
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