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1.
Protein Expr Purif ; 225: 106584, 2025 Jan.
Article in English | MEDLINE | ID: mdl-39178976

ABSTRACT

Lipases comprise the third most commercialized group of enzymes worldwide and those of microbial origin are sought for their multiple advantages. Agro-industrial waste can be an alternative culture medium for producing lipases, reducing production costs and the improper disposal of waste frying oil (WFO). This study aimed to produce yeast lipases through submerged fermentation (SF) using domestic edible oil waste as inducer and alternative culture medium. The optimal culture conditions, most effective inducer, and purification method for a new lipase from Moesziomyces aphidis BRT57 were identified. Yeast was cultured in medium containing green coconut pulp and WFO waste for 72 h. The maximum production of lipases in SF occurred in a culture medium containing WFO and yeast extract at 48 and 72 h of incubation, with enzyme activities of 8.88 and 11.39 U mL-1, respectively. The lipase was isolated through ultrafiltration followed by size exclusion chromatography, achieving a 50.46 % recovery rate. To the best of our knowledge, this is the first study to report the production and purification of lipases from M. aphidis, demonstrating the value of frying oil as inducer and alternative medium for SF, contributing to the production of fatty acids for biodiesel from food waste.


Subject(s)
Cocos , Lipase , Lipase/isolation & purification , Lipase/chemistry , Lipase/biosynthesis , Lipase/metabolism , Cocos/chemistry , Plant Oils/chemistry , Fermentation , Fungal Proteins/isolation & purification , Fungal Proteins/chemistry , Fungal Proteins/biosynthesis , Fungal Proteins/genetics
2.
Future Microbiol ; : 1-12, 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39101446

ABSTRACT

Aim: Evaluate the anticandidal effect of Croton heliotropiifolius Kunth essential oil and its interaction with azoles and N-acetylcysteine (NAC) against planktonic cells and biofilms. Materials & methods: Broth microdilution and checkerboard methods were used to evaluate the individual and combined activity with fluconazole and itraconazole (ITRA). The antibiofilm effect of the oil was assessed in 96-well plates alone and combined with ITRA and NAC, and cytotoxicity determined by MTT. Results: The oil inhibited all Candida species growth. The activity was enhanced when associated with ITRA and NAC for planktonic cells and biofilms in formation. The effective concentrations were lower than the toxic ones to V79 cells. Conclusion: C. heliotropiifolius Kunth essential oil is an anticandidal alternative, and can be associated with ITRA and NAC.


Candida is a type of fungus that can cause disease in people. In recent years, the number of available drugs to treat this disease have declined. It is important to search for new drugs. Plants are often used to improve health, so we tested the essential oil of a plant called Croton heliotropiifolius to see if it could kill the fungus. We found that the essential oil could kill the fungus, and could be used with other drugs to improve their effects.

3.
Protein Expr Purif ; 222: 106534, 2024 Oct.
Article in English | MEDLINE | ID: mdl-38897399

ABSTRACT

Tribolium castaneum, also known as the red flour beetle, is a polyphagous pest that seriously damages agricultural products, including stored and processed grains. Researchers have aimed to discover alternative pest control mechanisms that are less harmful to the ecosystem than those currently used. We conduct the purification and characterization of a protease inhibitor from C. plumieri seeds and an in vitro evaluation of its insecticidal potential against the insect pest T. castaneum. The trypsin inhibitor was isolated from C. plumieri seeds in a single-step DEAE-Sepharose column chromatography and had a molecular mass of 50 kDA. When analyzed for interaction with different proteolytic enzymes, the inhibitor exhibited specificity against trypsin and no activity against other serine proteases such as chymotrypsin and elastase-2. The isolated inhibitor was able to inhibit digestive enzymes of T. castaneum from extracts of the intestine of this insect. Therefore, we conclude that the new protease inhibitor, specific in tryptic inhibition, of protein nature from the seeds of C. plumieri was effective in inhibiting the digestive enzymes of T. castaneum and is a promising candidate in the ecological control of pests.


Subject(s)
Tribolium , Trypsin Inhibitors , Animals , Trypsin Inhibitors/pharmacology , Trypsin Inhibitors/chemistry , Trypsin Inhibitors/isolation & purification , Tribolium/enzymology , Tribolium/drug effects , Insect Proteins/chemistry , Insect Proteins/isolation & purification , Insect Proteins/antagonists & inhibitors , Seeds/chemistry , Insecticides/pharmacology , Insecticides/chemistry , Insecticides/isolation & purification , Plant Proteins/pharmacology , Plant Proteins/isolation & purification , Plant Proteins/chemistry
4.
J Toxicol Environ Health A ; 87(3): 91-107, 2024 02.
Article in English | MEDLINE | ID: mdl-37927232

ABSTRACT

Croton heliotropiifolius Kunth, popularly known as "velame," is a shrub that resides in northeastern Brazil. The essential oil of C. heliotropiifolius contains high concentrations of volatile compounds in the leaves and is widely used in folk medicine for many purposes as an antiseptic, analgesic, sedative, and anti-inflammatory agent. Due to the apparent limited amount of information, the aim of this study was to determine the cytotoxic potential of essential oil extracted from leaves of C. heliotropiifolius, utilizing different human cancer cell lines (HL-60, leukemia; HCT-116, colon; MDA-MB435, melanoma; SF295, glioblastoma) and comparison to murine fibroblast L929 cell line. The chemical characterization of the essential oil revealed the presence of large amounts of monoterpenes and sesquiterpenes, the majority of which were aristolene (22.43%), germacrene D (11.38%), ɣ-terpinene (10.85%), and limonene (10.21%). The essential oil exerted significant cytotoxicity on all cancer cells, with low activity on murine L929 fibroblasts, independent of disruption of cell membranes evidenced by absence of hemolytic activity. The cytotoxicity identified was associated with oxidative stress, which culminated in mitochondrial respiration dysfunction and direct or indirect DNA damage (strand breaks and oxidative damage), triggering cell death via apoptosis. Our findings suggest that extracts of essential oil of C. Heliotropiifolius may be considered as agents to be used therapeutically in treatment of certain cancers.


Subject(s)
Antineoplastic Agents , Croton , Oils, Volatile , Sesquiterpenes , Humans , Animals , Mice , Oils, Volatile/pharmacology , Croton/chemistry , Cell Line, Tumor , Sesquiterpenes/analysis , Plant Leaves/chemistry
5.
Prep Biochem Biotechnol ; 54(7): 910-917, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38156982

ABSTRACT

Proteases are the main enzymes traded worldwide-comprising 60% of the total enzyme market-and are fundamental to the degradation and processing of proteins and peptides. Due to their high commercial demand and biological importance, there is a search for alternative sources of these enzymes. Crotalaria stipularia is highlighted for its agroecological applications, including organic fertilizers, nematode combat, and revegetation of areas contaminated with toxic substances. Considering the pronounced biotechnological functionality of the studied species and the necessity to discover alternative sources of proteases, we investigated the extraction, purification, and characterization of a protease from seeds of the C. stipularia plant. Protease isolation was achieved by three-phase partitioning and single-step molecular exclusion chromatography in Sephacryl S-100, with a final recovery of 47% of tryptic activity. The molecular mass of the isolated enzyme was 40 kDa, demonstrating optimal activities at pH 8.0 and 50 °C. Enzymatic characterization demonstrated that the protease can hydrolyze the specific trypsin substrate, BApNA. This trypsin-like protease had a Km, Vmax, Kcat, and catalytic efficiency constant of 0.01775 mg/mL, 0.1082 mM/min, 3.86 s-1, and 217.46, respectively.


Subject(s)
Crotalaria , Seeds , Crotalaria/chemistry , Seeds/chemistry , Seeds/enzymology , Hydrogen-Ion Concentration , Trypsin/metabolism , Trypsin/chemistry , Kinetics , Substrate Specificity , Temperature , Molecular Weight
6.
Nat Prod Res ; : 1-6, 2023 Dec 06.
Article in English | MEDLINE | ID: mdl-38054811

ABSTRACT

Herpes simplex virus type 2 (HSV-2) is the most common agent of sexually transmitted infections around the world. Currently, no vaccine is available, and acyclovir is the reference compound in treatment HSV-2 infections. However, the emergence of resistant strains has reduced the efficacy in treatment. Several studies have shown marine seaweed biological activities, but there are no studies yet about the activity anti-HSV-2 of two its secundary metabolites, atomaric acid (1) and marine dolastane (2), isolated from Stypopodium zonale and Canistrocarpus cervicornis respectively. Therefore, we evaluated the anti-HSV-2 activity of compounds 1 and 2. Both compounds showed anti-HSV-2 activity with low cytotoxicity and compound 1 inactivated 90% of the viral particles at 50 µM. Both compounds inhibited the penetration and results in silico indicated the compound 1 as possible therapy alternative anti -HSV-2.

7.
Injury ; 54 Suppl 6: 110777, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38143129

ABSTRACT

The treatment of severe musculoskeletal injuries, such as loss of bone tissue and consolidation disorders, requires bone transplantation, and the success of this bone reconstruction depends on the grafts transplant's osteogenic, osteoconductive, and osteoinductive properties. Although the gold standard is autograft, it is limited by availability, morbidity, and infection risk. Despite their low capacity for osteoinduction and osteogenesis, decellularized bone allografts have been used in the search for alternative therapeutic strategies to improve bone regeneration. Considering that bone marrow stromal cells (BMSCs) are responsible for the maintenance of bone turnover throughout life, we believe that associating BMSCs with allograft could produce a material that is biologically similar to autologous bone graft. For this reason, this study evaluated the osteogenic potential of bone allograft cellularized with BMSCs. First, BMSC was characterized and allograft decellularization was confirmed by histology, scanning electron microscopy, and DNA quantification. Subsequently, the BMSCs and allografts were associated and evaluated for adhesion, proliferation, and in vitro and in vivo osteogenic potential. We demonstrated that, after 2 hours, BMSCs had already adhered to the surface of allografts and remained viable for 14 days. In vitro osteogenic assays indicated increased osteogenic potential of allografts compared with beta-tricalcium phosphate (ß-TCP). In vivo transplantation assays in immunodeficient mice confirmed the allograft's potential to induce bone formation, with significantly better results than ß-TCP. Finally, our results indicate that allograft can provide structural support for BMSC adhesion, offering a favorable microenvironment for cell survival and differentiation and inducing new bone formation. Taken together, our data indicate that this rapid methodology for cellularization of allograft with BMSCs might be a new therapeutic alternative in regenerative medicine and bone bioengineering.


Subject(s)
Bone Regeneration , Mesenchymal Stem Cells , Humans , Mice , Animals , Calcium Phosphates/pharmacology , Osteogenesis , Cell Differentiation , Allografts , Bone Marrow Cells
8.
Microbiol Spectr ; : e0117523, 2023 Aug 21.
Article in English | MEDLINE | ID: mdl-37607068

ABSTRACT

People with cystic fibrosis (pwCF) experience a range of persistent gastrointestinal symptoms throughout life. There is evidence indicating interaction between the microbiota and gut pathophysiology in CF. However, there is a paucity of knowledge on the potential effects of CF transmembrane conductance regulator (CFTR) modulator therapies on the gut microbiome. In a pilot study, we investigated the impact of Tezacaftor/Ivacaftor dual combination CFTR modulator therapy on the gut microbiota and metabolomic functioning in pwCF. Fecal samples from 12 pwCF taken at baseline and following placebo or Tezacaftor/Ivacaftor administration were subjected to microbiota sequencing and to targeted metabolomics to assess the short-chain fatty acid (SCFA) composition. Ten healthy matched controls were included as a comparison. Inflammatory calprotectin levels and patient symptoms were also investigated. No significant differences were observed in overall gut microbiota characteristics between any of the study stages, extended also across intestinal inflammation, gut symptoms, and SCFA-targeted metabolomics. However, microbiota and SCFA metabolomic compositions, in pwCF, were significantly different from controls in all study treatment stages. CFTR modulator therapy with Tezacaftor/Ivacaftor had negligible effects on both the gut microbiota and SCFA composition across the course of the study and did not alter toward compositions observed in healthy controls. Future longitudinal CFTR modulator studies will investigate more effective CFTR modulators and should use prolonged sampling periods, to determine whether longer-term changes occur in the CF gut microbiome. IMPORTANCE People with cystic fibrosis (pwCF) experience persistent gastrointestinal (GI) symptoms throughout life. The research question "how can we relieve gastrointestinal symptoms, such as stomach pain, bloating, and nausea?" remains a top priority for clinical research in CF. While CF transmembrane conductance regulator (CFTR) modulator therapies are understood to correct underlying issues of CF disease and increasing the numbers of pwCF are now receiving some form of CFTR modulator treatment. It is not known how these therapies affect the gut microbiome or GI system. In this pilot study, we investigated, for the first time, effects of the dual combination CFTR modulator medicine, Tezacaftor/Ivacaftor. We found it had negligible effects on patient GI symptoms, intestinal inflammation, or gut microbiome composition and functioning. Our findings are important as they fill important knowledge gaps on the relative effectiveness of these widely used treatments. We are now investigating triple combination CFTR modulators with prolonged sampling periods.

9.
J Biomed Mater Res B Appl Biomater ; 110(11): 2521-2532, 2022 11.
Article in English | MEDLINE | ID: mdl-35779044

ABSTRACT

Prior to clinical use, the corrosion resistance of new prosthesis system must be verified. The fretting-corrosion mechanisms of total hip arthroplasty (THA) implants generate metal debris and ions that can increase the incidence of adverse tissue reactions. For cemented stems, there are at least two interfaces that can be damaged by fretting-corrosion: stem-head and stem-cement. This investigation aimed to evaluate, through in vitro and in silico analyses, fretting-corrosion at the stem-head and stem-cement interfaces, to determine which surface is most affected in pre-clinical testing and identify the causes associated with the observed behavior. Unimodular stems and femoral heads of three different groups were evaluated, defined according to the head/stem material as group I (SS/SS), group II (CoCr/SS), and group III (CoCr/CoCr). Seven pairs of stems and heads per group were tested: three pairs were subjected to material characterization, three pairs to in vitro fretting-corrosion testing, and one pair to geometric modeling in the in silico analysis. The absolute area of the stem body degraded was more than three times higher compared with the trunnion, for all groups. These results were corroborated by the in silico analysis results, which revealed that the average micromotion at the stem-cement interface (9.65-15.66 µm) was higher than that at the stem-head interface (0.55-1.08 µm). In conclusion, the degradation of the stem-cement interface is predominant in the pre-clinical set, indicating the need to consider the fretting-corrosion at the stem-cement interface during pre-clinical implant evaluations.


Subject(s)
Arthroplasty, Replacement, Hip , Hip Prosthesis , Arthroplasty, Replacement, Hip/methods , Bone Cements , Computer Simulation , Corrosion , Dental Materials , Glass Ionomer Cements , Humans , Prosthesis Design , Prosthesis Failure
10.
Rejuvenation Res ; 25(4): 173-180, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35607849

ABSTRACT

Muscle weakness is associated with negative outcomes, in addition to being related to the pathogenesis of frailty and functional disability in the older individuals. Muscle strength and functionality are considered biomarkers of aging. Progressive resistance training (PRT) is a type of training that has been the subject of studies as it presents itself as a therapeutic option to fight the reduction of muscle strength and functionality in older individuals. However, few studies have assessed the clinically relevant gains in the levels of muscle strength and functionality of older individuals after PRT, in addition to the need of testing new PRT approaches, including individualization and periodization in training programs. Therefore, this article aims to assess the effect of an individual and periodized PRT protocol on handgrip strength (HS) and functionality in older individuals. Thus, the study sample included 69 older individuals, divided into 2 groups: case (n = 41) and control (n = 28). The case group participated in a PRT protocol for 12 weeks, with two weekly sessions. When compared to the control group, which received only health education, the individuals in the case group had a greater magnitude of improvement in all variables related to the assessed functionality (Timed up and go test, gait speed, and HS), proving the applicability of the assessed protocol to improve strength and functionality in the older individuals of a community.


Subject(s)
Resistance Training , Aged , Hand Strength , Humans , Muscle Strength/physiology , Postural Balance , Resistance Training/methods , Time and Motion Studies
11.
Motriz (Online) ; 28: e10220020021, 2022. tab, graf
Article in English | LILACS | ID: biblio-1386377

ABSTRACT

Abstract Aim: To evaluate the chronic effects of resistance training on resting blood pressure, handgrip strength, gait speed, and Timed Up and Go test (TUG) in normotensive and hypertensive elderly individuals. Methods: Experimental study based on TREND. Hypertensive patients were diagnosed by an independent doctor. Before and after 12 weeks of progressive resistance training, we evaluated blood pressure, heart rate, body composition, Timed Up and Go test, gait speed, and handgrip strength. Results: Sample consisted of 41 participants divided into two groups (normotensive n = 28; hypertensive n = 13). We observed significant values in the reduction of blood pressure levels only in the group of hypertensive participants. In functionality outcomes, we observed significant values in all tests and both groups. Outcomes contemplate effect sizes ranging from small to moderate. Conclusion: Progressive resistance training lowers resting blood pressure levels, increases handgrip strength, and improves physical functional performance. Although the normotensive group did not show a reduction in blood pressure levels, an improvement was observed in the functional physical tests.


Subject(s)
Humans , Aged , Aged, 80 and over , Exercise/physiology , Hand Strength/physiology , Physical Functional Performance , Health Services for the Aged , Hypertension/physiopathology
12.
Front Physiol ; 12: 619054, 2021.
Article in English | MEDLINE | ID: mdl-33776788

ABSTRACT

INTRODUCTION: The purpose of this study was to: (i) investigate the effect of six months of resistance training (RT) on body composition, muscle strength, hematological patterns, and redox profile in maintenance hemodialysis (HD) patients, and; (ii) evaluate the effects of baseline concentrations of hemoglobin on the RT response. METHODS: One hundred fifty-seven subjects with chronic kidney disease (CKD) were randomly allocated into two groups: Control [CTL, (n = 76)] and RT (n = 81). A first visit was required for anamnesis and anthropometric measurements. Venous blood samples were collected at baseline and after twenty-four weeks of training in all patients for the analysis of clinical and redox balance markers. The RT program spanned six months and consisted of three sets of 8-12 repetitions with a rating of perceived exertion between 5 and 8 for three weekly sessions. Each exercise session was performed in twelve resistance exercises and it least for approximately 40 min. RESULTS: The main results demonstrated that RT decreased waist circumference by 3%, and decreased thiobarbituric reactive species (TBARS) by 28%. Moreover, RT increased handgrip strength by 28.4%, fat-free mass by 4.1%, hemoglobin by 5%, iron by 33.4%, glutathione by 121%, and Trolox equivalent antioxidant capacity by 14.2% (p < 0.05). Low hemoglobin concentrations impaired the effect of RT on fat-free mass gain. CONCLUSION: Six months of RT in HD patients improved clinical parameters, such as hemoglobin, iron, body composition, and redox balance, while low hemoglobin concentration impaired exercise-benefits on fat-free mass in patients with CKD. These findings can contribute to a better clinical application of RT in the maintenance of hemodialysis patients.

13.
Rev. bras. cir. plást ; 34(1): 151-155, jan.-mar. 2019. ilus
Article in English, Portuguese | LILACS | ID: biblio-994623

ABSTRACT

O lentigo maligno (LM) é uma forma de melanoma in situ que mais comumente se apresenta como uma mácula de crescimento lentamente progressivo, pigmentada, na face de idosos com pele danificada pelo sol. Esse melanoma in situ tem um risco (30% a 50%) de progressão para lentigo maligno melanoma. A excisão cirúrgica completa da lesão requer margens de pelo menos 10mm, mesmo para lesões in situ. Porém, quando o crescimento de LM ocorre em áreas de implicações estéticas ou funcionais (face, pescoço, solas), a excisão é frequentemente reduzida para preservar estruturas anatômicas importantes e por razões cosméticas. Além disso, as margens periféricas podem ser clinicamente mal definidas e nem sempre pigmentadas, com extensão subestimada e risco de ressecção insuficiente. A "técnica de espaguete", descrita por Gaudy Marqueste, é uma cirurgia estratégica baseada na amostragem de uma faixa de tecido "spaghettilike" para determinar as margens da lesão antes da remoção do tumor. Após a confirmação anatomopatológica de margens livres de neoplasia, a lesão principal central é ressecada, permitindo a reconstrução do defeito no mesmo procedimento, sendo uma alternativa à cirurgia micrográfica de Mohs.(AU)


Lentigo maligna (LM) is a melanoma in situ that commonly presents as a macula with progressive and irregularly pigmented growth, especially in the face of elderly people with sun-damaged skin. This melanoma in situ has a risk (30-50%) of progression to lentigo maligna melanoma. Complete surgical excision of the lesion requires margins of at least 10 mm, even for lesions in situ. However, when the growth of LM occurs in areas of aesthetic or functional implications (face, neck, and soles), the excision is often reduced to preserve important anatomic structures and for cosmetic purposes. Moreover, the peripheral margins may be clinically ill-defined and not always pigmented, and thus, such cases are associated with underestimated extension and risk of insufficient resection. The "spaghetti" technique, described by Gaudy Marqueste, is a strategic surgical approach based on sampling of a range of "spaghetti-like" strips to determine the margins of the lesion prior to removal of the tumor. After the pathological confirmation of neoplasia-free margins, the main central lesion is resected, allowing reconstruction of the defect in the same procedure, as an alternative to Mohs micrographic surgery. (AU)


Subject(s)
Humans , Male , Middle Aged , Skin Neoplasms , Hutchinson's Melanotic Freckle/physiopathology , Plastic Surgery Procedures/methods , Nasal Surgical Procedures/methods , Melanocytes/pathology , Melanoma/complications , Melanoma/diagnosis , Plastic Surgery Procedures/methods , Melanoma/surgery
14.
J Psychiatr Res ; 107: 57-67, 2018 12.
Article in English | MEDLINE | ID: mdl-30326340

ABSTRACT

Major depressed patients show increased bacterial translocation with elevated plasma levels of lipopolysaccharide (LPS), which may trigger immune-inflammatory and neuro-oxidative responses. Recently, an animal model based on chronic LPS administration was developed which was associated with long-lasting depressive-like and neuro-oxidative alterations in female mice. The aim of the current study was to investigate behavioral, neuroimmune and neuroprogressive alterations in female mice 6 weeks after LPS chronic exposure. Female mice received increasing doses of LPS during 5 days at one-month intervals repeated for 4 consecutive months. Six weeks after the last LPS-exposure, we assessed behavioral despair and anhedonia, microglial activation, alterations in tryptophan, 5-HT, kynurenine, quinolinic acid (QUIN) levels and spermidine/spermine N1-acetyltransferase (SAT1) expression in the hippocampus, both with and without fluoxetine administration. Our results show that six weeks post-LPS, mice present behavioral despair and anhedonia in association with increased IBA1 expression (a microglia activation marker), NF-kB p65 and IL-1ß levels, indoleamine 2,3-dioxygenase (IDO1) mRNA expression, kynurenine, QUIN levels and QUIN/tryptophan ratio, and lowered tryptophan, 5-HT levels and SAT1 mRNA expression. Fluoxetine reversed the behavioral and neuroimmune alterations but had no effect in the reversal of IDO1 increased expression, QUIN levels and QUIN/tryptophan ratio. In conclusion, our results support the validity of the chronic LPS model of major depression and additionally shows its translational relevance with respect to neuroimmune and neuroprogressive pathways.


Subject(s)
Behavior, Animal/drug effects , Depressive Disorder, Major/chemically induced , Depressive Disorder, Major/drug therapy , Depressive Disorder, Major/immunology , Fluoxetine/pharmacology , Lipopolysaccharides/pharmacology , Selective Serotonin Reuptake Inhibitors/pharmacology , Serotonin/metabolism , Tryptophan/drug effects , Animals , Disease Models, Animal , Female , Fluoxetine/administration & dosage , Lipopolysaccharides/administration & dosage , Mice , Selective Serotonin Reuptake Inhibitors/administration & dosage
15.
Bioresour Technol ; 270: 263-269, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30223157

ABSTRACT

A halotolerant endoglucanase with a molecular mass of 39 kDa was obtained from the solid fermentation of sugarcane bagasse by the fungus Botrytis ricini URM 5627 and isolated using only two purification processes: fractionation with ammonium sulphate and size-exclusion chromatography resulting in an activity of 1289.83 U/mL. After the isolation, biochemical characterizations were performed, giving a temperature of 50 °C and optimum pH of 5. The enzyme was stable at 39-60 °C for 60 min and at a pH of 4-6. The enzymatic activity increased in the presence of Na+, Mn2+, Mg2+ and Zn2+ and decreased in the presence of Ca2+, Cu2+, and Fe2+. The endoglucanase revealed a halotolerant profile since its activity increased proportionally to an increase in NaCl concentration. The maximum activity was reached at 2 M NaCl with a 75% increase in activity. The enzyme had a Km of 0.1299 ±â€¯0.0096 mg/mL and a Vmax of 0.097 ±â€¯0.00121 mol/min/mL. During application in saccharification tests, the enzyme was able to hydrolyse sugarcane bagasse, rice husk, and wheat bran, with the highest production of reducers/fermentable sugars within 24 h of saccharification for wheat bran (137.21 mg/g). Therefore, these properties combined make this isolated enzyme a potential candidate for biotechnological and industrial applications.


Subject(s)
Botrytis/enzymology , Cellulase/metabolism , Dietary Fiber , Enzyme Stability , Fermentation , Hydrogen-Ion Concentration , Hydrolysis , Saccharum/metabolism , Temperature
16.
J Environ Manage ; 183(Pt 3): 771-776, 2016 Dec 01.
Article in English | MEDLINE | ID: mdl-27652581

ABSTRACT

Because of its precision and accuracy, Pb-Fire assay is the most employed method for gold analysis in geological materials. At the second stage of the method, namely cupellation, lead is oxidized to PbO which is absorbed by the cupel, leading to metallic gold as a tiny bend at the bottom of the recipient. After cupellation, cupel becomes highly contaminated with lead, making its disposal a serious risk of environmental contamination. In the present work, a leaching process for removing lead from cupel waste is proposed, which allowed for removing 96% of PbO by weight. After a precipitation step, 92.0% of lead was recovered from leachates in the form of PbSO4. Lead in the solid wastes left by the extraction was above the limit established by Brazilian legislation and these were classified as non-hazardous. Finally, secondary effluents generated after the precipitation step presented lead content more than twenty times lower than that of leachates from cupel waste. Tons of cupel waste are annually generated from gold analysis by Pb-Fire assay. Thus, the proposed method can contribute to prevent the discharge of high amounts of lead into the environment. Also, recovery of lead can help to partially meet the industrial demand for lead compounds.


Subject(s)
Gold/analysis , Hazardous Waste , Lead/isolation & purification , Refuse Disposal/methods , Solid Waste , Brazil , Hazardous Waste/analysis , Hazardous Waste/legislation & jurisprudence , Lead/analysis , Solid Waste/analysis
17.
Int J Biol Macromol ; 91: 980-6, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27327905

ABSTRACT

Animal venoms are complex mixtures, including peptides, proteins (i.e., enzymes), and other compounds produced by animals in predation, digestion, and defense. These molecules have been investigated regarding their molecular mechanisms associated with physiological action and possible pharmacological applications. Recently, we have described the presence of a type of angiotensin converting enzyme (ACE) activity in the venom of Thalassophryne nattereri. It is a zinc-dependent peptidase with a wide range of effects. By removing dipeptide His-Leu from terminal C, the ACE converts angiotensinI (AngI) into angiotensin II (AngII) and inactivates bradykinin, there by regulating blood pressure and electrolyte homeostasis. The fractionation of T. nattereri venom in CM-Sepharose indicated a peak (CM2) with angiotensin-converting activity, converting AngI into Ang II. Electrophoresis on polyacrylamide gel (12%) revealed one band with 30kDa for CM2 similar in size to natterins, which are toxins with proteolytic activity found in T. nattereri venom. Mass spectrometry indicated that the protein sequence of the ACE purified from T. nattereri venom corresponds to natterin 1. The isolated protein has also demonstrated inhibition through captopril and EDTA and is characterized as a classic ACE. Thus, the isolated enzyme purified from T. nattereri venom is the first ACE isolated from fish venom.


Subject(s)
Batrachoidiformes/metabolism , Fish Venoms/enzymology , Peptidyl-Dipeptidase A/metabolism , Amino Acid Sequence , Animals , Cations , Chromatography, High Pressure Liquid , Chromatography, Ion Exchange , Electrophoresis, Polyacrylamide Gel , Peptidyl-Dipeptidase A/chemistry , Peptidyl-Dipeptidase A/isolation & purification , Sequence Alignment
18.
J Mech Behav Biomed Mater ; 62: 71-82, 2016 09.
Article in English | MEDLINE | ID: mdl-27179766

ABSTRACT

Modular hip prostheses are flexible to match anatomical variations and to optimize mechanical and tribological properties of each part by using different materials. However, micromotions associated with the modular components can lead to fretting corrosion and, consequently, to release of debris which can cause adverse local tissue reactions in human body. In the present study, the surface damage and residues released during in vitro fretting corrosion tests were characterized by stereomicroscope, SEM and EDS. Two models of modular hip prosthesis were studied: Model SS/Ti Cementless whose stem was made of ASTM F136 Ti-6Al-4V alloy and whose metallic head was made of ASTM F138 austenitic stainless steel, and Model SS/SS Cemented with both components made of ASTM F138 stainless steel. The fretting corrosion tests were evaluated according to the criteria of ASTM F1875 standard. Micromotions during the test caused mechanical wear and material loss in the head-taper interface, resulting in fretting-corrosion. Model SS/SS showed higher grade of corrosion. Different morphologies of debris predominated in each model studied. Small and agglomerated particles were observed in the Model SS/Ti and irregular particles in the Model SS/SS. After 10 million cycles, the Model SS/Ti was more resistant to fretting corrosion than the Model SS/SS.


Subject(s)
Hip Prosthesis , Prosthesis Design , Prosthesis Failure , Alloys , Corrosion , Humans , Stainless Steel , Surface Properties , Titanium
19.
Toxicon ; 119: 92-8, 2016 Sep 01.
Article in English | MEDLINE | ID: mdl-27215174

ABSTRACT

The venom of marine animals is a rich source of compounds with remarkable selectivity and functional diversity. Scorpaena plumieri is the most venomous fish in the Brazilian fauna and is responsible for relatively frequent accidents involving anglers and bathers. In humans, its venom causes edema, erythema, ecchymoses, anxiety, nausea, vomiting, and syncope. The venom is chemically characterized by Sp-CTx, a enzyme able to generate an initial endothelium-dependent relaxation response, followed by a contraction response. This study sought to investigate the proteolytic activities regarding vasopeptides angiotensin I and II. Both the venom and the epidermal mucus presented angiotensin conversion activity for angiotensin I, as well as a capacity to form Ang 1-7 directly via Ang I and II. Captopril (10 µM) and EDTA (1 mM) were able to abolish the converting activity of the venom and the epidermal mucus, representing the first description of a converting activity in S. plumieri venom and epidermal mucus.


Subject(s)
Angiotensins/metabolism , Epidermis/chemistry , Fish Venoms/toxicity , Mucus/chemistry , Animals , Chromatography, High Pressure Liquid , Fish Venoms/chemistry , Humans
20.
Int J Parasitol ; 46(5-6): 343-50, 2016 05.
Article in English | MEDLINE | ID: mdl-26953255

ABSTRACT

Repeated treatments with praziquantel reduce schistosomiasis prevalence and morbidity, but transmission persists and populations often recover within a few years. To identify factors associated with persistence, we surveyed and treated all identified Schistosoma mansoni infections in two rural Brazilian communities (Jenipapo and Volta do Rio) in 2009, 2012 and 2013. Eggs were collected from all infected individuals and genotyped with 11 microsatellite markers to evaluate parasite differentiation and diversity. After successive rounds of community-wide treatment, prevalence decreased from 45% to 24% then 16%. Intensity of infection decreased by 57% over this period, and the number of eggs transmitted to the environment decreased by 92%. During all time periods the majority of eggs were excreted by those >15years of age. The incidence was 23% in 2012 and 15% in 2013, consistent with a decrease in transmission. There was little immigration or gene flow over a distance of 6km. On reinfection, infrapopulations were moderately differentiated indicating that pretreatment multilocus genotypes were not fully reacquired. The effective population size responded to census population decline more rapidly than differentiation. Reinfection was concentrated in the downstream portion of Jenipapo, consistent with the observed increased human fecal contamination. At this scale and in this area S. mansoni infections exist on a fragmented landscape with a highly focal pattern of transmission that may facilitate future elimination.


Subject(s)
Anthelmintics/administration & dosage , Praziquantel/administration & dosage , Schistosoma mansoni/drug effects , Schistosomiasis mansoni/drug therapy , Adolescent , Adult , Aged , Aged, 80 and over , Animals , Anthelmintics/pharmacology , Anthelmintics/therapeutic use , Brazil/epidemiology , Child , Child, Preschool , Feces/parasitology , Female , Gene Frequency , Genotyping Techniques , Humans , Incidence , Infant , Longitudinal Studies , Male , Microsatellite Repeats , Middle Aged , Parasite Egg Count , Praziquantel/pharmacology , Praziquantel/therapeutic use , Prevalence , Risk Factors , Rural Population , Schistosoma mansoni/classification , Schistosoma mansoni/genetics , Schistosomiasis mansoni/epidemiology , Schistosomiasis mansoni/transmission , Young Adult
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