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1.
Int J Biol Macromol ; 280(Pt 1): 135596, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39276894

RESUMO

Lytic polysaccharide monooxygenases (LPMOs) are copper-dependent enzymes that oxidize polysaccharides, leading to their cleavage. LPMOs are classified into eight CAZy families (AA9-11, AA13-17), with the functionality of AA16 being poorly characterized. This study presents biochemical and structural data for an AA16 LPMO (PnAA16) from the marine sponge symbiont Peniophora sp. Phylogenetic analysis revealed that PnAA16 clusters separately from previously characterized AA16s. However, the structural modelling of PnAA16 showed the characteristic immunoglobulin-like fold of LPMOs, with a conserved his-brace motif coordinating a copper ion. The copper-bound PnAA16 showed greater thermal stability than its apo-form, highlighting copper's role in enzyme stability. Functionally, PnAA16 demonstrated oxidase activity, producing 5 µM H2O2 after 30 min, but showed 20 times lower peroxidase activity (0.27 U/g) compared to a fungal AA9. Specific activity assays indicated that PnAA16 acts only on cellohexaose, generating native celloligosaccharides (C3 to C5) and oxidized products with regioselective oxidation at C1 and C4 positions. Finally, PnAA16 boosted the activity of a cellulolytic cocktail for cellulose saccharification in the presence of ascorbic acid, hydrogen peroxide, or both. In conclusion, the present work provides insights into the AA16 family, expanding the understanding of their structural and functional relationships and biotechnological potential.

2.
Eur Heart J Imaging Methods Pract ; 2(2): qyae067, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-39224865

RESUMO

Aims: Rheumatic mitral stenosis (MS) frequently leads to impaired left atrial (LA) function because of pressure overload, highlighting the underlying atrial pathology. Two-dimensional speckle tracking echocardiography (2D-STE) offers early detection of LA dysfunction, potentially improving risk assessment in patients with MS. This study aims to evaluate the predictive value of LA function assessed by 2D-STE for clinical outcomes in patients with MS. Methods and results: Between 2011 and 2021, patients with MS underwent LA function assessment using 2D-STE, with focus on the reservoir phase (LASr). Atrial fibrillation (AF) development constituted the primary outcome, with death or valve replacement as the secondary outcome. Conditional inference trees were employed for analysis, validated through sample splitting. The study included 493 patients with MS (mean valve area 1.1 ± 0.4 cm2, 84% female). At baseline, 166 patients (34%) had AF, with 62 patients (19%) developing AF during follow-up. LASr emerged as the primary predictor for new-onset AF, with a threshold of 17.9%. Over a mean 3.8-year follow-up, 125 patients (25%) underwent mitral valve replacement, and 32 patients (6.5%) died. A decision tree analysis identified key predictors such as age, LASr, severity of tricuspid regurgitation (TR), net atrioventricular compliance (C n), and early percutaneous mitral valvuloplasty, especially in patients aged ≤49 years, where LASr, with a threshold of 12.8%, significantly predicted adverse outcomes. Conclusion: LASr emerged as a significant predictor of cardiovascular events in this MS cohort, validated through a decision tree analysis. Patients were stratified into low- or high-risk categories for adverse outcomes, taking into account LASr, age, TR severity, and C n.

3.
Genet Mol Biol ; 47(3): e20230107, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39133695

RESUMO

Genetic, epigenetic and environmental factors play an important role in the genesis of Type 2 Diabetes Mellitus (T2D). In the genetic context, one of the strategies used to investigate possible associations with diabetes is the search for Single Nucleotide Polymorphisms (SNPs), involving the comparison of alelle frequencies, the phenotypic variations and other relevant factors, such as environmental influences and lifestyle choices, Thus, the aim of this study was to find the relationship of risk variants for T2D in SNPs (rs4994) in the ADRB3 gene; (rs1799854) in the ABCC8 gene; (rs7901695 and rs12255372) in the TCF7L2 gene; and (rs8050136) in the FTO gene in a sample of the population of the municipality of Santarém (PA), Brazilian Amazon, in the northern region of Brazil. ABCC8 (rs1799854 C>T) showed a statistically significant association with T2D. Each chosen gene and SNP has been previously implicated in T2D risk according to existing scientific literature, owing to their roles in glucose regulation and body fat.

4.
Commun Biol ; 7(1): 704, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38851817

RESUMO

Aspergillus fumigatus represents a public health problem due to the high mortality rate in immunosuppressed patients and the emergence of antifungal-resistant isolates. Protein acetylation is a crucial post-translational modification that controls gene expression and biological processes. The strategic manipulation of enzymes involved in protein acetylation has emerged as a promising therapeutic approach for addressing fungal infections. Sirtuins, NAD+-dependent lysine deacetylases, regulate protein acetylation and gene expression in eukaryotes. However, their role in the human pathogenic fungus A. fumigatus remains unclear. This study constructs six single knockout strains of A. fumigatus and a strain lacking all predicted sirtuins (SIRTKO). The mutant strains are viable under laboratory conditions, indicating that sirtuins are not essential genes. Phenotypic assays suggest sirtuins' involvement in cell wall integrity, secondary metabolite production, thermotolerance, and virulence. Deletion of sirE attenuates virulence in murine and Galleria mellonella infection models. The absence of SirE alters the acetylation status of proteins, including histones and non-histones, and triggers significant changes in the expression of genes associated with secondary metabolism, cell wall biosynthesis, and virulence factors. These findings encourage testing sirtuin inhibitors as potential therapeutic strategies to combat A. fumigatus infections or in combination therapy with available antifungals.


Assuntos
Aspergilose , Aspergillus fumigatus , Sirtuínas , Aspergillus fumigatus/patogenicidade , Aspergillus fumigatus/genética , Aspergillus fumigatus/enzimologia , Sirtuínas/genética , Sirtuínas/metabolismo , Virulência , Animais , Camundongos , Aspergilose/microbiologia , Aspergilose/tratamento farmacológico , Acetilação , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Mariposas/microbiologia
5.
J Fungi (Basel) ; 10(6)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38921393

RESUMO

Trichoderma erinaceum is a filamentous fungus that was isolated from decaying sugarcane straw at a Brazilian ethanol biorefinery. This fungus shows potential as a source of plant cell wall-degrading enzymes (PCWDEs). In this study, we conducted a comprehensive multiomics investigation of T. erinaceum to gain insights into its enzymatic capabilities and genetic makeup. Firstly, we performed genome sequencing and assembly, which resulted in the identification of 10,942 genes in the T. erinaceum genome. We then conducted transcriptomics and secretome analyses to map the gene expression patterns and identify the enzymes produced by T. erinaceum in the presence of different substrates such as glucose, microcrystalline cellulose, pretreated sugarcane straw, and pretreated energy cane bagasse. Our analyses revealed that T. erinaceum highly expresses genes directly related to lignocellulose degradation when grown on pretreated energy cane and sugarcane substrates. Furthermore, our secretome analysis identified 35 carbohydrate-active enzymes, primarily PCWDEs. To further explore the enzymatic capabilities of T. erinaceum, we selected a ß-glucosidase from the secretome data for recombinant production in a fungal strain. The recombinant enzyme demonstrated superior performance in degrading cellobiose and laminaribiose compared to a well-known enzyme derived from Trichoderma reesei. Overall, this comprehensive study provides valuable insights into both the genetic patterns of T. erinaceum and its potential for lignocellulose degradation and enzyme production. The obtained genomic data can serve as an important resource for future genetic engineering efforts aimed at optimizing enzyme production from this fungus.

6.
J Peripher Nerv Syst ; 29(1): 97-106, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38375759

RESUMO

BACKGROUND AND AIMS: The genetic epidemiology of inherited neuropathies in children remains largely unknown. In this study, we specifically investigated the genetic profile of a Brazilian cohort of pediatric patients with pure or complex axonal neuropathies, a crucial knowledge in the near future for establishing treatment priorities and perspectives for this group of patients. METHODS: Fifty-three pediatric patients who were assessed prior to reaching the age of 20, and who had clinical diagnoses of axonal hereditary neuropathy or presented with axonal neuropathy as the primary clinical feature, were included in the study. The recruitment of these cases took place from January 1, 2018, to December 31, 2020. The diagnosis was based on clinical and electrophysiological data. A molecular assessment was made using target-gene panel or whole-exome sequencing. Subsequently, segregation analysis was performed on available family members, and all candidate variants found were confirmed through Sanger. RESULTS: A molecular diagnosis was reached in 68% of the patients (n = 36/53), considering only pathogenic and probably pathogenic variants. Variants in MFN2 (n = 15) and GJB1 (n = 3) accounted for half of the genetically confirmed patients (50%; n = 18/36). The other 18 genetically diagnosed patients had variants in several less common genes. INTERPRETATION: Apart from MFN2 and GJB1 genes, universally recognized as a frequent cause of axonal neuropathies in most studied population, our Brazilian cohort of children with axonal neuropathies showed an important genetic heterogeneity, probably reflecting the multi ethnicity of the Brazilian population. Diagnostic, counseling, and future interventions should consider this characteristic.


Assuntos
Doença de Charcot-Marie-Tooth , Humanos , Criança , Doença de Charcot-Marie-Tooth/genética , Brasil/epidemiologia , Mutação , Proteína beta-1 de Junções Comunicantes
7.
Blood Press Monit ; 29(2): 71-81, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300019

RESUMO

Different lifestyle changes have been employed to improve clinical hypertension. However, there is scarce evidence on the blood pressure responsiveness to resistance training (RT) in hypertensive older adults. Consequently, little is known about some participants clinically reducing blood pressure and others not. Thus, we investigate the effects and responsiveness of RT on blood pressure in hypertensive older adults. We secondarily evaluated the biochemical risk factors for cardiovascular disease and functional performance. Older participants with hypertension were randomly assigned into RT (n = 27) and control group (n = 25). Blood pressure, functional performance (timed up and go, handgrip strength, biceps curl and sit-to-stand), fasting glucose, and lipid profiles were evaluated preintervention and postintervention. The statistic was performed in a single-blind manner, the statistician did not know who was the control and RT. RT was effective in reducing systolic blood pressure (SBP) (pre 135.7 ±â€…14.7; post 124.7 ±â€…11.0; P  < 0.001) and the responses to RT stimuli varied noticeably between hypertensive older adults after 12 weeks. For example, 13 and 1 responders displayed a minimal clinical important difference for SBP attenuation (10.9 mmHg) in the RT and control groups, respectively. RT improved the functional performance of older people with hypertension, while no differences were found in biochemical parameters (triglycerides, HDL, LDL, fasting glucose) after 12 weeks. In conclusion, responses to RT stimuli varied noticeably between hypertensive individuals and RT was effective in reducing SBP.


Assuntos
Hipertensão , Treinamento Resistido , Humanos , Idoso , Pressão Sanguínea/fisiologia , Força da Mão , Método Simples-Cego , Hipertensão/terapia , Glucose
8.
J Dent ; 140: 104794, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38035453

RESUMO

OBJECTIVES: To evaluate if tooth color alteration of activated charcoal-based dentifrices may be attributed to the dye adsorption potential of charcoal (chemical action - C - slurry only) or to the association of dye adsorption with abrasion (chemo-mechanical action - CM- slurry/toothbrushing). Potential adverse effects in surface roughness, gloss, and wear were also assessed. METHODS: Bovine enamel/dentin specimens were randomly allocated into the groups according to treatments and test model (n = 15): deionized water (negative control- NC); Colgate Maximum Anticaries Protection (conventional toothpaste- positive control- PC); Colgate Luminous White Activated Charcoal (LW); Oral-B 3D White Therapy Charcoal (WT); Curaprox Black is White (BW); Dermavita Whitemax (Activated charcoal powder- WP). Specimens were exposed to the C or CM models, in 28-day staining-treatment cycling. Color change (ΔE00), whiteness index (ΔWID), percentage of alteration of surface roughness (%Raalt), and gloss (%GUalt) were calculated. Additional specimens (n = 9) were indented with a Knoop diamond and subjected to 100,000 abrasion cycles. Enamel wear was determined by calculating the decrease in indentations geometry. Data were analyzed by ANOVA/Tukey tests (α = 0.05). RESULTS: The CM-model produced lower color change (staining) than C (p = 0.0001). PC, LW, WT, BW, and WP showed similar color results for both models, differing from NC (p < 0.05).%Ra and%GU did not differ among the C-model groups (p > 0.05) and WP exhibited the highest variation (%Ra and%GU) under CM-model. Enamel wear values were lowest in the NC and PC groups, intermediate for LW, WT, BW, and highest for the WP (p < 0.05). CONCLUSION: Activated charcoal-based dentifrices have a similar ability to minimize tooth staining as the conventional toothpaste, with increased enamel wear potential in the long term (after 100,000 cycles). The activated charcoal powder damaged the enamel surface, showing a higher deleterious effect on enamel roughness, gloss, and wear. CLINICAL SIGNIFICANCE: Dentifrices containing activated charcoal do not provide superior results to minimize tooth staining compared to conventional toothpaste. Charcoal powder should be used with caution because it promotes higher superficial alterations on the enamel surface.


Assuntos
Dentifrícios , Cremes Dentais , Bovinos , Animais , Carvão Vegetal , Corantes , Pós , Escovação Dentária
9.
Acta Cir Bras ; 38: e383423, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37851781

RESUMO

PURPOSE: The aim of this study was to evaluate the effect of platelet-rich fibrin (PRF) and autograft on non-critical bone repair. METHODS: Four bone defects (8.3 × 2 mm) were produced on the calvarium of 15 rabbits. The surgical defects were treated with either autograft, autograft associated to PRF, PRF alone, and sham. Animals were euthanized on the second, fourth or sixth posteoperative week. Histological analyses for presence of bone development on deffect was evaluated comparing the groups treated with autograft and without the autograft separately within the same period. Mann-Whitney's tests were used to compare the percentage of bone repair in each post-operative period for autograft × autograft + PRF groups and also for control × PRF groups (α = 5%). RESULTS: No differences were observed between the groups that received autograft and autograft associated to PRF on the second and fourth postoperative week, but areas treated with PRF demonstrated significant osteogenesis when compared to sham group on the fourth and sixth weeks. The groups that received PRF (with autograft or alone) demonstrated an enlarged bone deposition when compared to their control group. CONCLUSIONS: The use of PRF may influence bone repair and improve the bone deposition in late period of repair demonstrating osteoconductive and osteogenic properties.


Assuntos
Fibrina Rica em Plaquetas , Animais , Coelhos , Crânio/cirurgia , Osteogênese , Regeneração Óssea , Transplante Autólogo
10.
bioRxiv ; 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37808717

RESUMO

Protein acetylation is a crucial post-translational modification that controls gene expression and a variety of biological processes. Sirtuins, a prominent class of NAD + -dependent lysine deacetylases, serve as key regulators of protein acetylation and gene expression in eukaryotes. In this study, six single knockout strains of fungal pathogen Aspergillus fumigatus were constructed, in addition to a strain lacking all predicted sirtuins (SIRTKO). Phenotypic assays suggest that sirtuins are involved in cell wall integrity, secondary metabolite production, thermotolerance, and virulence. AfsirE deletion resulted in attenuation of virulence, as demonstrated in murine and Galleria infection models. The absence of AfSirE leads to altered acetylation status of proteins, including histones and non-histones, resulting in significant changes in the expression of genes associated with secondary metabolism, cell wall biosynthesis, and virulence factors. These findings encourage testing sirtuin inhibitors as potential therapeutic strategies to combat A. fumigatus infections or in combination therapy with available antifungals.

11.
Int J Mol Sci ; 24(5)2023 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-36902388

RESUMO

CCR5Δ32 and SDF1-3'A polymorphisms were investigated in a cohort of viremia controllers, without the use of therapy, along with their influence on CD4+ T lymphocytes (TLs), CD8+ TLs, and plasma viral load (VL). The samples were analyzed from 32 HIV-1-infected individuals classified as viremia controllers 1 and 2 and viremia non-controllers, from both sexes, mostly heterosexuals, paired with 300 individuals from a control group. CCR5∆32 polymorphism was identified by PCR amplification of a fragment of 189 bp for the wild-type allele and 157 bp for the allele with the ∆32 deletion. SDF1-3'A polymorphism was identified by PCR, followed by enzymatic digestion (restriction fragment length polymorphism) with the Msp I enzyme. The relative quantification of gene expression was performed by real-time PCR. The distribution of allele and genotype frequencies did not show significant differences between the groups. The gene expression of CCR5 and SDF1 was not different between the profiles of AIDS progression. There was no significant correlation between the progression markers (CD4+ TL/CD8+ TL and VL) and the CCR5∆32 polymorphism carrier status. The 3'A allele variant was associated with a marked loss of CD4+ TLs and a higher plasma VL. Neither CCR5∆32 nor SDF1-3'A was associated with viremia control or the controlling phenotype.


Assuntos
Síndrome da Imunodeficiência Adquirida , Quimiocina CXCL12 , Infecções por HIV , Receptores CCR5 , Feminino , Humanos , Masculino , Síndrome da Imunodeficiência Adquirida/genética , Biomarcadores , Brasil , Quimiocina CXCL12/genética , Progressão da Doença , Frequência do Gene , HIV-1 , Receptores CCR5/genética , Viremia
12.
Acta cir. bras ; Acta cir. bras;38: e383423, 2023. graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1513541

RESUMO

Purpose: The aim of this study was to evaluate the effect of platelet-rich fibrin (PRF) and autograft on non-critical bone repair. Methods: Four bone defects (8.3 × 2 mm) were produced on the calvarium of 15 rabbits. The surgical defects were treated with either autograft, autograft associated to PRF, PRF alone, and sham. Animals were euthanized on the second, fourth or sixth posteoperative week. Histological analyses for presence of bone development on deffect was evaluated comparing the groups treated with autograft and without the autograft separately within the same period. Mann-Whitney's tests were used to compare the percentage of bone repair in each post-operative period for autograft × autograft + PRF groups and also for control × PRF groups (α = 5%). Results: No differences were observed between the groups that received autograft and autograft associated to PRF on the second and fourth postoperative week, but areas treated with PRF demonstrated significant osteogenesis when compared to sham group on the fourth and sixth weeks. The groups that received PRF (with autograft or alone) demonstrated an enlarged bone deposition when compared to their control group. Conclusions: The use of PRF may influence bone repair and improve the bone deposition in late period of repair demonstrating osteoconductive and osteogenic properties.


Assuntos
Animais , Coelhos , Osteogênese , Plaquetas , Regeneração Óssea , Fibrina
13.
J Peripher Nerv Syst ; 27(4): 316-319, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36222432

RESUMO

The distal hereditary motor neuropathies (dHMN) encompass a group of peripheral nervous system disorders characterized by progressive distal predominant weakness and wasting, usually in a length-dependent pattern. The classical neurophysiological pattern is a motor axonal neuropathy with chronic distal denervation/reinnervation on needle examination. Conduction block (CB) and temporal dispersion (TD) are electrophysiological features classically associated with acquired demyelinating neuropathies. Although they have rarely been reported in hereditary neuropathies, to date they have not been described in dHMN. We report a sporadic case of a patient with neurophysiological criteria consistent with multifocal motor neuropathy with CB (MMN) refractory to immunomodulation. WES revealed a homozygous nonsense pathogenic variant in sigma nonopioid intracellular receptor-1 gene (SIGMAR1). SIGMAR1-related disorders have been reported with distinctive features suggesting it is not a typical length-dependent neuropathy. Nevertheless, CB and TD are unexpected and as far as we have known not been described previously in such patients. This case expands the neurophysiological spectrum of this disease and alerts clinicians to this acquired demyelinating motor neuropathy mimic.


Assuntos
Doenças do Sistema Nervoso Periférico , Humanos , Condução Nervosa
14.
Stud Health Technol Inform ; 290: 145-149, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35672988

RESUMO

OBJECTIVE: This article presents a mobile application model for the treatment tracking of in-hospital wounds. METHODS: A survey of the literature on mobile apps for wound monitoring was carried out. Health professionals were interviewed and wound forms were analyzed to synthesize the application's fields and features. We designed the application model using a prototyping tool. RESULTS: The prototype features interfaces for patient evaluation, different functionalities according to the role of the health professional, a dashboard for monitoring the open admissions, selection of wound locations using a body model, treatment prescribing, tracking the wounds using photos, and generating wound reports. CONCLUSION: The adoption of this application could optimize wounds' treatment, increase patient safety, reduce material expenditures and time for professionals with rework in the dressing procedure.


Assuntos
Aplicativos Móveis , Pessoal de Saúde , Humanos , Inquéritos e Questionários
15.
Int J Palliat Nurs ; 28(5): 208-213, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35648683

RESUMO

BACKGROUND: The grieving process following perinatal loss caused by life-limiting conditions presents some particularities associated with the family's culture and the symbolic relationship with the deceased. OBJECTIVE: To reflect on the symbolic meaning attributed to mementos, particularly pictures taken immediately after birth. METHOD: Case study-a qualitative analysis of the data collected through semidirected interviews. RESULTS: Of the three women that took part in the study, one woman chose not to take a picture but opted to take home the hat with her son's name on it that was provided as a regular procedure for every birth at the maternity centre. During the interview, she questioned her decision. The two other women took pictures and still look at them affectionate. One of the women keeps the picture of her child in a shrine at home, thus attributing a symbolic religious meaning to the whole experience that alleviates her pain. CONCLUSION: The symbolic meaning attributed to pictures of the deceased can help parents process grief.


Assuntos
Morte Perinatal , Feminino , Pesar , Humanos , Recém-Nascido , Núcleo Familiar , Pais , Gravidez
16.
Microbiol Spectr ; 10(3): e0212521, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-35658600

RESUMO

Lytic polysaccharide monooxygenases (LPMOs) are oxidative enzymes found in viruses, archaea, and bacteria as well as eukaryotes, such as fungi, algae and insects, actively contributing to the degradation of different polysaccharides. In Aspergillus nidulans, LPMOs from family AA9 (AnLPMO9s), along with an AA3 cellobiose dehydrogenase (AnCDH1), are cosecreted upon growth on crystalline cellulose and lignocellulosic substrates, indicating their role in the degradation of plant cell wall components. Functional analysis revealed that three target LPMO9s (AnLPMO9C, AnLPMO9F and AnLPMO9G) correspond to cellulose-active enzymes with distinct regioselectivity and activity on cellulose with different proportions of crystalline and amorphous regions. AnLPMO9s deletion and overexpression studies corroborate functional data. The abundantly secreted AnLPMO9F is a major component of the extracellular cellulolytic system, while AnLPMO9G was less abundant and constantly secreted, and acts preferentially on crystalline regions of cellulose, uniquely displaying activity on highly crystalline algae cellulose. Single or double deletion of AnLPMO9s resulted in about 25% reduction in fungal growth on sugarcane straw but not on Avicel, demonstrating the contribution of LPMO9s for the saprophytic fungal lifestyle relies on the degradation of complex lignocellulosic substrates. Although the deletion of AnCDH1 slightly reduced the cellulolytic activity, it did not affect fungal growth indicating the existence of alternative electron donors to LPMOs. Additionally, double or triple knockouts of these enzymes had no accumulative deleterious effect on the cellulolytic activity nor on fungal growth, regardless of the deleted gene. Overexpression of AnLPMO9s in a cellulose-induced secretome background confirmed the importance and applicability of AnLPMO9G to improve lignocellulose saccharification. IMPORTANCE Fungal lytic polysaccharide monooxygenases (LPMOs) are copper-dependent enzymes that boost plant biomass degradation in combination with glycoside hydrolases. Secretion of LPMO9s arsenal by Aspergillus nidulans is influenced by the substrate and time of induction. These findings along with the biochemical characterization of novel fungal LPMO9s have implications on our understanding of their concerted action, allowing rational engineering of fungal strains for biotechnological applications such as plant biomass degradation. Additionally, the role of oxidative players in fungal growth on plant biomass was evaluated by deletion and overexpression experiments using a model fungal system.


Assuntos
Aspergillus nidulans , Oxigenases de Função Mista , Aspergillus nidulans/genética , Celulose/química , Celulose/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Lignina , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Polissacarídeos , Secretoma
17.
SciELO Preprints; jun. 2022.
Preprint em Português | SciELO Preprints | ID: pps-4328

RESUMO

Introduction: Simultaneously with the development of new biomaterials, numerous surgical modalities have been proposed, with the aim of promoting adequate regeneration of bone defects, without providing fenestrations or dehiscence. Among the regenerative techniques currently accepted for this purpose, guided tissue regeneration (GTR) stands out. Objective: To evaluate the healing pattern and the histological response of the organism to the insertion of a type A gelatin-based membrane, and to compare it with a commercial membrane. Methods: Fifteen adult rabbits were selected. In the parietal region of the calvaria, flaps were performed to create a supraperiosteal pouch and implantation of 2 types of resorbable membranes: Marquette membrane and Bio-Gide® membrane. After the surgical procedure, the animals were allocated into 3 randomly selected groups (n=5) for the period of euthanasia, which occurred at 2, 4 and 6 postoperative weeks. Subsequently, the calvaria areas were removed and stained by H&E and analyzed for periosteum formation, inflammatory infiltrate in the area of membrane insertion, membrane degradation/resorption, and perimembrane fibrosis. Results: A slight inflammatory infiltration occurred around the Bio-Gide® membrane and it underwent resorption during the postoperative period with periosteum reconstruction, predominantly of a fibrous nature. The Marquette membrane also did not trigger an important inflammatory reaction. However, there was no significant resorption during the period; there was also significant formation of fibrous capsule surrounding the entire membrane area. Conclusion: The Marquette membrane produces tissue isolation reaction, minimizing periosteal formation while not providing its degradation


Introdução: Simultaneamente ao desenvolvimento de novos biomateriais, abundantes modalidades cirúrgicas têm sido propostas, com a finalidade de promover adequada regeneração de defeitos ósseos, sem proporcionar 2 fenestrações ou deiscências. Entre as técnicas regenerativas atualmente aceitas para este propósito, destaca-se a regeneração tecidual guiada (RTG). Objetivo: Avaliar o padrão de cicatrização e a resposta histológica do organismo frente à inserção de uma membrana a base de gelatina tipo A, e compará-la com membrana comercial. Métodos: Foram selecionadas 15 coelhas adultas. Na região parietal da calvária foram realizados retalhos para criação de uma bolsa supraperiostal e implantação de 2 tipos de membranas reabsorvíveis: membrana Marquette e membrana Bio-Gide®. Após o procedimento cirúrgico os animais foram alocados em 3 grupos randomicamente selecionados (n=5) para o período de eutanásia, que ocorreu em 2, 4 e 6 semanas pós-operatórias. Posteriormente, as áreas da calvária foram removidas e coradas por H&E e analisadas para averiguar formação de periósteo, infiltrado inflamatório na área de inserção de membrana, degradação/reabsorção da membrana, e fibrose perimembranar. Resultados: Ao redor da membrana Bio-Gide® ocorreu discreta infiltração inflamatória e a membrana sofreu reabsorção ao decorrer do período pósoperatório com reconstrução de periósteo prevalentemente de caráter fibroso. A membrana Marquette também não desencadeou importante reação inflamatória. Contudo, não foi verificada reabsorção significativa durante o período, também ocorreu significante formação de cápsula fibrosa cerceando toda área membranar. Conclusão: A membrana Marquette produz reação de isolamento tecidual, minimizando a formação periostal ao mesmo tempo que não proporciona sua degradação.

18.
SciELO Preprints; jun. 2022.
Preprint em Português | SciELO Preprints | ID: pps-4224

RESUMO

Introduction: L-PRF (platelet and leukocyte-rich fibrin) is a concentrate of platelets and leukocytes in a fibrin network, obtained by autologous centrifugation collected at the time of the operation. It offers the advantages of low cost, easy preparation, simple acquisition and ability to accelerate the healing of soft and hard tissues. Objective: To evaluate the bone repair of non-critical defects in rabbit calvaria using L-PRF alone and in association with particulate autogenous bone. Method: Fifteen rabbits were used with blood collected and immediately centrifuged. Four non-critical defects measuring 8 mm in diameter were performed and filled with: 1) particulate autogenous bone; 2) particulate autogenous bone + L-PRF; 3) L-PRF only; and 4) without graft. They were sacrificed after 2, 4 and 6 weeks with the samples analyzed histologically and histomorphometrically comparing the regenerated areas. Results: At 2 weeks there was a statistical difference between groups 1 and 3; at 4 weeks there was between groups 2 and 4; and at 6 weeks between groups 1 and 4 and between 3 and 4. There was significant bone and proportional gain between 2 and 6 weeks for the L-PRF group. Conclusion: L-PRF alone had a positive and proportional effect on bone formation over the weeks.


Introdução: O L-PRF (fibrina rica em plaquetas e leucócitos) é concentrado de plaquetas e leucócitos em uma rede de fibrina, obtido pela centrifugação autóloga coletada no momento da operação. Oferece como vantagens o baixo custo, fácil preparo, de simples obtenção e com capacidade de acelerar a cicatrização de tecidos moles e duros. Objetivo: Avaliar o reparo ósseo de defeitos não críticos em calvária de coelhos utilizando o L-PRF isoladamente e em associação com osso autógeno particulado. Método: Foram utilizados 15 coelhos com sangue coletado e imediatamente centrifugado. Foram realizados 4 defeitos não críticos de 8 mm de diâmetro e tratados com preenchimento por: 1) osso autógeno particulado; 2) osso autógeno particulado + L-PRF; 3) somente L-PRF; e 4) sem enxerto. Foram sacrificados após 2, 4 e 6 semanas com as amostras analisadas histologicamente e histomorfometricamente comparando as áreas regenerada. Resultados: Com 2 semanas houve diferença estatística entre os grupos 1 e 3; com 4 semanas entre os grupos 2 e 4; e com 6 semanas entre os grupos 1 e 4 e entre 3 e 4. Houve ganho ósseo e proporcional significativo entre 2 e 6 semanas para o grupo de L-PRF. Conclusão: O L-PRF isoladamente teve efeito positivo e proporcional na formação óssea no decorrer das semanas.

19.
Arq. ciências saúde UNIPAR ; 26(2): 127-133, maio-ago. 2022.
Artigo em Português, Francês | LILACS | ID: biblio-1372962

RESUMO

Objetivo: caracterizar a prática clínica e identificar as barreiras relacionadas à mobilização precoce em uma Unidade de Terapia Intensiva. Método: estudo observacional analítico e prospectivo que incluiu pacientes em ventilação mecânica por mais de 24 horas. Foram coletados diariamente dados clínicos, critérios de segurança, barreiras e atividades realizadas nos atendimentos de fisioterapia. Posteriormente a amostra foi dividida de acordo com a realização de sedestação à beira do leito. Utilizou-se teste T para comparação entre grupos e para associação teste Qui-quadrado ou Exato de Fischer quando necessário. Resultados: participaram 54 indivíduos com média de idade 51,33±14,85 anos e SAPSIII médio de 63,47±13,37 pontos. A mobilização foi realizada em 1356 sessões, em sua maioria atividades passivas. Nenhuma atividade fora do leito foi realizada com pacientes em ventilação mecânica. As principais barreiras foram sedação, nível de consciência e procedimentos médicos. A não sedestação à beira do leito foi associada à ausência de critérios de segurança, que impediram a mobilização, e ocorrência de óbito. Conclusão: A mobilização foi realizada na maioria das sessões, porém poucas atividades foram realizadas fora do leito. Durante o período de ventilação mecânica nenhuma atividade foi realizada fora do leito. As barreiras mais citadas foram sedação, nível de consciência e procedimentos médicos.


Purpose: characterize the clinical practice and identify barriers related to early mobilization in an Intensive Care Unit. Method: analytical and prospective observational study that included patients on mechanical ventilation for more than 24 hours. Clinical data, safety criteria, barriers and activities performed in physical therapy consultations were collected on a daily basis. Subsequently, the sample was divided according to the performance of the patient sitting at the bedside. The T-test was used for comparison between groups and the Chi-square test or Fisher's exact test were used when necessary. Results: a total of 54 individuals participated, with a mean age of 51.33±14.85 years and mean SAPSIII of 63.47±13.37 points. Mobilization was performed in 1356 sessions, mostly passive activities. No out-of-bed activities were performed with patients on mechanical ventilation. The main barriers were sedation, level of consciousness, and medical procedures. Failure to sit at the bedside was associated with the absence of safety criteria, which prevented mobilization, and the occurrence of death. Conclusion: Mobilization was performed in most sessions, but few activities were performed outside the bed. During the period of mechanical ventilation, no activity was performed outside the bed. The barriers most frequently mentioned were sedation, level of consciousness, and medical procedures.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Conhecimentos, Atitudes e Prática em Saúde , Deambulação Precoce , Unidades de Terapia Intensiva , Respiração Artificial , Modalidades de Fisioterapia , Estado de Consciência , Morte , Limitação da Mobilidade , Sedação Profunda , Fisioterapeutas , Métodos
20.
Genet Mol Biol ; 45(2): e20210153, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35560161

RESUMO

This study was carried out to investigate the frequency of genetic variants related to body mass index (BMI) and type 2 diabetes (T2D) and evaluating the potential impact of risk alleles on susceptibility to these disorders in six indigenous peoples from Brazilian Amazon region. The majority of Fst values for pairwise population comparisons among the indigenous groups are low or moderate. The indigenous people show high values of differentiation with Africans, Europeans and Southeast Asians and moderate values with East Asian and American populations, as expected. The allelic frequencies among indigenous indicate that the majority of associations observed with T2D in continental populations can be replicated in native Amazonians. The genetic risk scores calculated for T2D in indigenous are high and similar to those calculated for Americans and East Asians, while the estimates obtained for obesity are low, probably due to the low frequencies of the risk allele of the FTO gene found in our samples. ADRB3-rs4994 and ABCC8-rs1799854 genes showed a significant association with BMI and waist circumference, and the KCNJ11-rs5219 gene with hyperglycemia. These results emphasize the importance of knowing the genetic variability underlying complex genetic diseases in indigenous peoples and the search for particular or rare variants.

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