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1.
Nat Commun ; 15(1): 3975, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38729930

RESUMO

Oxidoreductases have evolved tyrosine/tryptophan pathways that channel highly oxidizing holes away from the active site to avoid damage. Here we dissect such a pathway in a bacterial LPMO, member of a widespread family of C-H bond activating enzymes with outstanding industrial potential. We show that a strictly conserved tryptophan is critical for radical formation and hole transference and that holes traverse the protein to reach a tyrosine-histidine pair in the protein's surface. Real-time monitoring of radical formation reveals a clear correlation between the efficiency of hole transference and enzyme performance under oxidative stress. Residues involved in this pathway vary considerably between natural LPMOs, which could reflect adaptation to different ecological niches. Importantly, we show that enzyme activity is increased in a variant with slower radical transference, providing experimental evidence for a previously postulated trade-off between activity and redox robustness.


Assuntos
Proteínas de Bactérias , Oxigenases de Função Mista , Oxirredução , Oxigenases de Função Mista/metabolismo , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/química , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Domínio Catalítico , Triptofano/metabolismo , Polissacarídeos/metabolismo , Mutação , Estresse Oxidativo , Tirosina/metabolismo , Modelos Moleculares , Histidina/metabolismo , Histidina/genética
2.
Polymers (Basel) ; 16(9)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38732711

RESUMO

This study investigates the effect of scaffold architecture on bone regeneration, focusing on 3D-printed polylactic acid-bioceramic calcium phosphate (PLA-bioCaP) composite scaffolds in rabbit femoral condyle critical defects. We explored two distinct scaffold designs to assess their influence on bone healing and scaffold performance. Structures with alternate (0°/90°) and helical (0°/45°/90°/135°/180°) laydown patterns were manufactured with a 3D printer using a fused deposition modeling technique. The scaffolds were meticulously characterized for pore size, strut thickness, porosity, pore accessibility, and mechanical properties. The in vivo efficacy of these scaffolds was evaluated using a femoral condyle critical defect model in eight skeletally mature New Zealand White rabbits. Then, the results were analyzed micro-tomographically, histologically, and histomorphometrically. Our findings indicate that both scaffold architectures are biocompatible and support bone formation. The helical scaffolds, characterized by larger pore sizes and higher porosity, demonstrated significantly greater bone regeneration than the alternate structures. However, their lower mechanical strength presented limitations for use in load-bearing sites.

3.
Gerontology ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38574485

RESUMO

INTRODUCTION: Concurrent training has been shown to be a beneficial approach to improve overall health status in older adults. However, little is known about the adaptations of this type of training in the long term (i.e., after cessation of exercise), even less in older people affected by frailty syndrome.Therefore, this study aimed i) to assess the effects of a 6-week concurrent training program composed of power-oriented resistance training (RT) and fast walking interval training (FWIT) on physical function, muscle power, disability in activities of daily living and frailty in pre-frail and frail older people, and ii) to assess the effects of a 6-month detraining period on these outcomes. METHODS: A total of 59 pre-frail and frail older adults (>75 years old; Frailty Phenotype >1) were allocated into intervention (INT; n=32; 81.8 years; 21 women) or control (CON; n=27; 82.5 years; 19 women) groups. Primary outcomes of this study were Short Physical Performance Battery (SPPB), relative sit-to-stand (STS) power, Barthel index, Lawton scale and Frailty Phenotype. Assessments were performed at baseline (PRE), after the concurrent training programme (POST) and after 6 months of follow-up (DET) in both groups. Mixed model repeated measures ANOVA with Bonferroni's post hoc tests was used. RESULTS: Immediately after the intervention (∆= POST-PRE), INT improved SPPB (∆=3.0 points; p<0.001), relative STS power (∆=0.87 W·kg-1; p<0.001) and reduced their frailty levels (∆=-1.42 criteria; p<0.001), while no changes were observed in CON. After 6 months of detraining (∆= DET-PRE), INT showed higher SPPB (∆=2.2 points; p<0.001), higher relative STS power (∆=0.73 W·kg-1; p<0.001) and lower frailty (∆=-1.24 criteria; p<0.001) values than those reported at baseline, which were significantly different than those reported by CON. Both, Barthel index and Lawton scale values were not modified during the study in either group. CONCLUSIONS: The 6-week concurrent training program improved physical function, muscle power and reduced frailty in pre-frail and frail older people and these improvements were maintained above baseline levels after 6 months of detraining. However, due to the individual variability found, future studies of long-term responders vs. non-responders in frail populations are required.

4.
Eur J Appl Physiol ; 124(2): 623-632, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37688638

RESUMO

OBJECTIVES: To analyse the force-velocity relationship changes in response to two different training programmes differing in the set configuration (cluster vs. traditional), and their impact on physical function and frailty in pre-frail and frail older adults. METHODS: 43 pre-frail and frail (Frailty Phenotype ≥ 1 criteria) older adults (81.4 ± 5.1 years) participated in this study. Participants were assigned to cluster (CT; n = 10; 10-s intra-set rest), traditional (TT; n = 13; no intra-set rest) or control (CON; n = 20) groups. Force-velocity relationship (F0, V0 and Pmax), physical function (Short Physical Performance Battery, SPPB) and frailty (Frailty Phenotype, FP) were assessed at baseline and after the training programme. RESULTS: Both CT and TT groups showed similar improvements in Pmax after training (CT = + 36.7 ± 34.2 W; TT = + 33.8 ± 44.6 W; both p < 0.01). V0 was improved by both CT (+ 0.08 ± 0.06 m s-1; p < 0.01), and TT (+ 0.07 ± 0.15 m s-1, p > 0.05). F0 remained unchanged in CT (+ 68.6 ± 224.2 N, p > 0.05) but increased in TT (+ 125.4 ± 226.8 N, p < 0.05). Finally, SPPB improved in both training conditions (CT = + 2.3 ± 1.3 points; TT = + 3.0 ± 1.2 points; both p < 0.05) and in the CON group (+ 0.9 ± 1.4 points, p < 0.05). CT and TT reduced their FP (CT = - 1.1 criteria; TT = - 1.6 criteria; both p < 0.01), while no changes were observed in the CON group (- 0.2 criteria, p = 0.38). CONCLUSIONS: Both training methods were equally effective for improving Pmax, physical function and reducing frailty in pre-frail and frail older people. TT may be effective for improving both force and velocity parameters, while CT may be effective for improving velocity parameters alone, although further research is required to confirm these findings.


Assuntos
Fragilidade , Treinamento Intervalado de Alta Intensidade , Treinamento Resistido , Humanos , Idoso , Idoso Fragilizado
5.
J Neurol Sci ; 455: 122787, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37979414

RESUMO

The USA spends more in healthcare per capita than any other country in the world, but ranks last among high-income industrialized nations in major markers of healthcare effectiveness such as life expectancy, maternal mortality, neonatal mortality, and infant mortality. Unlike other high-income industrialized nations, the USA does not have a national agency that systematically evaluates the cost-effectiveness of health care interventions and negotiates their price accordingly. This manuscript aims to introduce the rationale, terminology, advantages, and limitations of cost-effectiveness analysis. Cost-effectiveness analysis compares health interventions and evaluates their incremental value and their incremental cost compared with already existing healthcare interventions. Cost-effectiveness analysis integrates the best available evidence with patients' preferences to inform clinical decision making. Patients with neurological conditions are facing increasing challenges to access healthcare and prescription drugs. Cost-effectiveness analysis may help improve access to the most effective healthcare interventions and prescription drugs while containing healthcare costs.


Assuntos
Análise de Custo-Efetividade , Neurologia , Lactente , Recém-Nascido , Humanos , Análise Custo-Benefício , Custos de Cuidados de Saúde
6.
Semin Pediatr Neurol ; 47: 101079, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37919036

RESUMO

COGNITIVE AND BEHAVIORAL COMORBIDITIES: AN UNWANTED EFFECT OF ANTIEPILEPTIC DRUGS IN CHILDREN: Adriana Ulate-Campos, Iván Sánchez Fernández Seminars in Pediatric Neurology Volume 24, Issue 4, November 2017, Pages 320-330 Epilepsy is one of the most common neurological disorders and, despite optimally chosen and dosed antiepileptic drugs (AEDs), approximately 20%-30% of patients will continue to have seizures. Behavior and cognition are negatively impacted by seizures, but AEDs are also a major contributor to behavioral and cognitive deficits. However, the cognitive and behavioral effect of AEDs in children is insufficiently emphasized in the literature. This review summarizes the cognitive and behavioral effects of AEDs in the pediatric population with the objective of helping pediatricians and pediatric neurologists to select the AEDs with the best profile for their individual patient's needs.


Assuntos
Transtornos Cognitivos , Epilepsia , Humanos , Criança , Anticonvulsivantes/efeitos adversos , Epilepsia/tratamento farmacológico , Epilepsia/psicologia , Convulsões/tratamento farmacológico , Comorbidade
7.
Genet Sel Evol ; 55(1): 74, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37880572

RESUMO

BACKGROUND: In spite of the availability of single nucleotide polymorphism (SNP) array data, differentiation between observed homozygosity and that caused by mating between relatives (autozygosity) introduces major difficulties. Homozygosity estimators show large variation due to different causes, namely, Mendelian sampling, population structure, and differences among chromosomes. Therefore, the ascertainment of how inbreeding is reflected in the genome is still an issue. The aim of this research was to study the usefulness of genomic information for the assessment of genetic diversity in the highly endangered Gochu Asturcelta pig breed. Pedigree depth varied from 0 (founders) to 4 equivalent discrete generations (t). Four homozygosity parameters (runs of homozygosity, FROH; heterozygosity-rich regions, FHRR; Li and Horvitz's, FLH; and Yang and colleague's FYAN) were computed for each individual, adjusted for the variability in the base population (BP; six individuals) and further jackknifed over autosomes. Individual increases in homozygosity (depending on t) and increases in pairwise homozygosity (i.e., increase in the parents' mean) were computed for each individual in the pedigree, and effective population size (Ne) was computed for five subpopulations (cohorts). Genealogical parameters (individual inbreeding, individual increase in inbreeding, and Ne) were used for comparisons. RESULTS: The mean F was 0.120 ± 0.074 and the mean BP-adjusted homozygosity ranged from 0.099 ± 0.081 (FLH) to 0.152 ± 0.075 (FYAN). After jackknifing, the mean values were slightly lower. The increase in pairwise homozygosity tended to be twofold higher than the corresponding individual increase in homozygosity values. When compared with genealogical estimates, estimates of Ne obtained using FYAN tended to have low root-mean-squared errors. However, Ne estimates based on increases in pairwise homozygosity using both FROH and FHRR estimates of genomic inbreeding had lower root-mean-squared errors. CONCLUSIONS: Parameters characterizing homozygosity may not accurately depict losses of variability in small populations in which breeding policy prohibits matings between close relatives. After BP adjustment, the performance of FROH and FHRR was highly consistent. Assuming that an increase in homozygosity depends only on pedigree depth can lead to underestimating it in populations with shallow pedigrees. An increase in pairwise homozygosity computed from either FROH or FHRR is a promising approach for characterizing autozygosity.


Assuntos
Endogamia , Polimorfismo de Nucleotídeo Único , Humanos , Suínos , Animais , Linhagem , Homozigoto , Genoma , Genótipo
8.
Seizure ; 112: 128-138, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37832279

RESUMO

OBJECTIVE: To describe the evolution in use and cost of antiseizure medications (ASM) in the United States of America (USA). METHODS: Retrospective descriptive study using the IBM MarketScan Commercial Database (data of privately-insured patients) for the years 2006 to 2021. We identified patients with epilepsy who were on ASM. We adjusted cost for inflation with the Gross Domestic Product Implicit Price Deflator. RESULTS: We evaluated 347,158 patients (46.9 % males; median (p25-p75) age: 33 (17-49) years; 28 % with pediatric-onset epilepsy and 72 % with adult-onset epilepsy) with a total of 1,385,382 person-years and 588,285,065 ASM prescription days. The most commonly prescribed (as percentage of prescription days) ASMs in 2006 were valproate (18 %) and lamotrigine (17 %) in pediatric-onset epilepsy and phenytoin (21 %) and carbamazepine (17 %) in adult-onset epilepsy, but starting in the 2010s, levetiracetam and lamotrigine became the most commonly prescribed ASMs in both pediatric-onset (in 2021, levetiracetam 25 %, lamotrigine 16 %) and adult-onset (in 2021, levetiracetam 27 %, lamotrigine 20 %) epilepsy. The proportion of generic ASM use increased 3.6-fold: from 23 % of prescription days in 2006 to 83 % of prescription days in 2021. The median (p25-p75) average wholesale price (AWP) per person-year increased by 102 % from $2,684 ($990-$5,509) in 2006 to $5,417 ($2,858-$12,310) in 2021. The increases were greater in absolute terms for brand-name ASMs by 419 %: $3,109 ($1,564-$5,068 in 2006 and $16,149 ($12,950-$23,377) in 2021 than for generic ASMs by 462 %: $699 ($457-$1,678) in 2006 and $3,931 ($2,618-$6,081) in 2021. The costs directly borne by the patient (copay, coinsurance, deductibles, and pharmacy processing fees) increased by 69 % for brand-name ASMs from $393 ($246-$570) in 2006 to $665 ($335-$1,308) in 2021, but decreased by 37 % for generic ASMs from $147 ($98-$213) in 2006 to $92 ($51-$141) in 2021. CONCLUSIONS: The median cost of ASMs per person-year approximately doubled from 2006 to 2021. The increase in use of generic ASMs probably helped buffer the growing costs of ASMs. However, generic ASMs already represent 83 % of prescription days in 2021, with limited room to further contain costs by just increasing the proportion of generics.


Assuntos
Epilepsia , Fenitoína , Adulto , Masculino , Criança , Humanos , Feminino , Lamotrigina , Levetiracetam , Estudos Retrospectivos , Medicamentos Genéricos/uso terapêutico , Epilepsia/tratamento farmacológico , Epilepsia/epidemiologia , Anticonvulsivantes/uso terapêutico
9.
Theriogenology ; 212: 157-171, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37729817

RESUMO

Reproductive failure is one of the main performance constraints in ruminant livestock. Transmissible agents such as Toxoplasma gondii and Neospora caninum are commonly involved in the occurrence of abortion in ruminants, but little is known about the mechanisms involved. While in vivo models are optimal for the study of abortion pathogenesis, they have a high economic cost and come with ethical concerns. Unfortunately, alternative in vitro models fail to replicate the complex in vivo placental structure. To overcome the limitations of currently available models, we developed an ex vivo model based on the cultivation of fresh and cryopreserved sheep placental explants, enabling the biobanking of tissues. Reproducible and simple markers of tissue integrity (histology, RNA concentrations), viability (resazurin reduction), and functionality (synthesis of steroid hormones) were also investigated, allowing a clear quality assessment of the model. This work shows that, similar to fresh explants, tissues cryopreserved in ethylene glycol using slow freezing rates maintain not only their structure and function but also their receptivity to T. gondii and N. caninum infection. In addition, the findings demonstrate that explant lifespan is mainly limited by the culture method, with protocols requiring improvements to extend it beyond 2 days. These findings suggest that cryopreserved tissues can be exploited to study the initial host‒pathogen interactions taking place in the placenta, thus deepening the knowledge of the specific mechanisms that trigger reproductive failure in sheep. Importantly, this work paves the way for the development of similar models in related species and contributes to the reduction of experimental animal use in the future.

10.
Genomics ; 115(5): 110700, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37598732

RESUMO

The recent advent of long-read sequencing technologies, such as Pacific Biosciences (PacBio) and Oxford Nanopore technology (ONT), has led to substantial accuracy and computational cost improvements. However, de novo whole-genome assembly still presents significant challenges related to the computational cost and the quality of the results. Accordingly, sequencing accuracy and throughput continue to improve, and many tools are constantly emerging. Therefore, selecting the correct sequencing platform, the proper sequencing depth and the assembly tools are necessary to perform high-quality assembly. This paper evaluates the primary assembly reconstruction from recent hybrid and non-hybrid pipelines on different genomes. We find that using PacBio high-fidelity long-read (HiFi) plays an essential role in haplotype construction with respect to ONT reads. However, we observe a substantial improvement in the correctness of the assembly from high-fidelity ONT datasets and combining it with HiFi or short-reads.


Assuntos
Genoma , Sequenciamento de Nucleotídeos em Larga Escala , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de DNA/métodos
11.
J Am Chem Soc ; 145(34): 18888-18903, 2023 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-37584157

RESUMO

Lytic polysaccharide monooxygenases (LPMOs) are powerful monocopper enzymes that can activate strong C-H bonds through a mechanism that remains largely unknown. Herein, we investigated the role of a conserved glutamine/glutamate in the second coordination sphere. Mutation of the Gln in NcAA9C to Glu, Asp, or Asn showed that the nature and distance of the headgroup to the copper fine-tune LPMO functionality and copper reactivity. The presence of Glu or Asp close to the copper lowered the reduction potential and decreased the ratio between the reduction and reoxidation rates by up to 500-fold. All mutants showed increased enzyme inactivation, likely due to changes in the confinement of radical intermediates, and displayed changes in a protective hole-hopping pathway. Electron paramagnetic resonance (EPR) and X-ray absorption spectroscopic (XAS) studies gave virtually identical results for all NcAA9C variants, showing that the mutations do not directly perturb the Cu(II) ligand field. DFT calculations indicated that the higher experimental reoxidation rate observed for the Glu mutant could be reconciled if this residue is protonated. Further, for the glutamic acid form, we identified a Cu(III)-hydroxide species formed in a single step on the H2O2 splitting path. This is in contrast to the Cu(II)-hydroxide and hydroxyl intermediates, which are predicted for the WT and the unprotonated glutamate variant. These results show that this second sphere residue is a crucial determinant of the catalytic functioning of the copper-binding histidine brace and provide insights that may help in understanding LPMOs and LPMO-inspired synthetic catalysts.


Assuntos
Cobre , Oxigenases de Função Mista , Oxigenases de Função Mista/química , Cobre/química , Peróxido de Hidrogênio/metabolismo , Polissacarídeos/metabolismo , Glutamatos
12.
Animals (Basel) ; 13(14)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37508128

RESUMO

Copy number variations regions (CNVRs) can be classified either as segregating, when found in both parents, and offspring, or non-segregating. A total of 65 segregating and 31 non-segregating CNVRs identified in at least 10 individuals within a dense pedigree of the Gochu Asturcelta pig breed was subjected to enrichment and functional annotation analyses to ascertain their functional independence and importance. Enrichment analyses allowed us to annotate 1018 and 351 candidate genes within the bounds of the segregating and non-segregating CNVRs, respectively. The information retrieved suggested that the candidate genes spanned by segregating and non-segregating CNVRs were functionally independent. Functional annotation analyses allowed us to identify nine different significantly enriched functional annotation clusters (ACs) in segregating CNVR candidate genes mainly involved in immunity and regulation of the cell cycle. Up to five significantly enriched ACs, mainly involved in reproduction and meat quality, were identified in non-segregating CNVRs. The current analysis fits with previous reports suggesting that segregating CNVRs would explain performance at the population level, whereas non-segregating CNVRs could explain between-individuals differences in performance.

13.
Front Immunol ; 14: 1198609, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37520552

RESUMO

Research on bovine neosporosis has achieved relevant milestones, but the mechanisms underlying the occurrence of foetal death or protection against foetal death remain unclear. In a recent study, placentas from heifers challenged with the high-virulence isolate Nc-Spain7 exhibited focal necrosis and inflammatory infiltrates as soon as 10 days post-infection (dpi), although parasite detection was minimal. These lesions were more frequent at 20 dpi, coinciding with higher rates of parasite detection and the occurrence of foetal death in some animals. In contrast, such lesions were not observed in placentas from animals infected with the low-virulence isolate Nc-Spain1H, where the parasite was detected only in placenta from one animal at 20 dpi. This work aimed to study which mechanisms are triggered in the placentas (caruncles and cotyledons) of these pregnant heifers at early stages of infection (10 and 20 dpi) through whole-transcriptome analysis. In caruncles, infection with the high-virulence isolate provoked a strong proinflammatory response at 10 dpi. This effect was not observed in heifers infected with the low-virulence isolate, where IL-6/JAK/STAT3 signalling and TNF-alpha signalling via NF-κB pathways were down-regulated. Interestingly, the expression of E2F target genes, related to restraining the inflammatory response, was higher in these animals. At 20 dpi, more pronounced proinflammatory gene signatures were detectable in heifers infected with the high-virulence isolate, being more intense in heifers carrying dead fetuses. However, the low-virulence isolate continued without activating the proinflammatory response. In cotyledons, the response to infection with the high-virulence isolate was similar to that observed in caruncles; however, the low-virulence isolate induced mild proinflammatory signals at 20 dpi. Finally, a deconvolutional analysis of gene signatures from both placentome tissues revealed a markedly higher fraction of activated natural killers, M1 macrophages and CD8+ T cells for the high-virulence isolate. Therefore, our transcriptomic analysis supports the hypothesis that an intense immune response probably triggered by parasite multiplication could be a key contributor to abortion. Further studies are required to determine the parasite effectors that govern the distinct interactions of high- and low-virulence isolates with the host, which could help elucidate the molecular processes underlying the pathogenesis of neosporosis in cattle.


Assuntos
Neospora , Gravidez , Humanos , Bovinos , Animais , Feminino , Virulência , Placenta/patologia , Perfilação da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Morte Fetal
14.
Seizure ; 111: 51-55, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37523933

RESUMO

PURPOSE: Delayed treatment in status epilepticus (SE) is independently associated with increased treatment resistance, morbidity, and mortality. We describe the prehospital management pathway and Emergency Medical Services (EMS) timeliness in children who developed refractory convulsive status epilepticus (RCSE). METHODS: Retrospective multicenter study in the United States using prospectively collected observational data from June 2011 to March 2020. We selected pediatric patients (one month-21 years) with RCSE initiated outside the hospital and transported to the hospital by EMS. RESULTS: We included 91 patients with a median (percentile25-percentile75) age of 3.0 (1.5-7.3) years. The median time from seizure onset to hospital arrival was 45 (30-67) minutes, with a median time cared for by EMS of 24 (15-36) minutes. Considering treatment by caregivers and EMS before hospital arrival, 20 (22%) patients did not receive any anti-seizure medications (ASM) and 71 (78%) received one to five doses of benzodiazepines (BZD), without non-BZD ASM. We provided the prehospital treatment flow path of these patients through caregivers and EMS including relevant time points. Patients with a history of SE were more likely to receive the first BZD in the prehospital setting compared to patients without a history of SE (adjusted HR 3.25, 95% CI 1.72-6.12, p<0.001). CONCLUSION: In this multicenter study of pediatric RCSE, prehospital treatment may be streamlined further. Patients with a history of SE were more likely to receive prehospital rescue medication.

15.
Vet Parasitol ; 320: 109981, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37450963

RESUMO

Fasciolosis is a globally widespread trematodiasis with a major economic and veterinary impact. Therefore, this disease is responsible for millions of dollars in losses to the livestock industry, and also constitutes an emerging human health problem in endemic areas. The ubiquitous nature of Fasciola hepatica, the main causative agent, is one of the key factors for the success of fasciolosis. Accordingly, this parasite is able to subsist in a wide variety of ecosystems and hosts, thanks to the development of a plethora of strategies for adaption and immune evasion. Fasciolosis comprises a growing concern due to its high prevalence rates, together with the emergence of strains of the parasite resistant to the treatment of choice (triclabendazole). These facts highlight the importance of developing novel control measures which allow for an effective protection against the disease before F. hepatica settles in a niche inaccessible to the immune system. However, knowledge about the initial phases of the infection, including the migration mechanisms of the parasite and the early innate host response, is still scarce. Recently, our group developed an in vitro host-parasite interaction model that allowed the early events to be unveiled after the first contact between the both actors. This occurs shortly upon ingestion of F. hepatica metacercariae and the emergence of the newly excysted juveniles (FhNEJ) in the host duodenum. Here, we present a transcriptomic analysis of such model using an approach based on RNA sequencing (RNA-Seq), which reveals changes in gene expression related to proteolysis and uptake of metabolites in FhNEJ. Additionally, contact with the parasite triggered changes in host intestinal cells related to pseudogenes expression and host defence mechanisms, including immune response, among others. In sum, these results provide a better understanding of the early stages of fasciolosis at molecular level, and a pool of targets that could be used in future therapeutic strategies against the disease.


Assuntos
Fasciola hepatica , Fasciolíase , Humanos , Animais , Fasciola hepatica/fisiologia , Transcriptoma , Ecossistema , Fasciolíase/veterinária , Células Epiteliais
16.
Acta Biomater ; 168: 1-21, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37454707

RESUMO

3D-printed composite scaffolds have emerged as an alternative to deal with existing limitations when facing bone reconstruction. The aim of the study was to systematically review the feasibility of using PLA/bioceramic composite scaffolds manufactured by 3D-printing technologies as bone grafting materials in preclinical in vivo studies. Electronic databases were searched using specific search terms, and thirteen manuscripts were selected after screening. The synthesis of the scaffolds was carried out using mainly extrusion-based techniques. Likewise, hydroxyapatite was the most used bioceramic for synthesizing composites with a PLA matrix. Among the selected studies, seven were conducted in rats and six in rabbits, but the high variability that exists regarding the experimental process made it difficult to compare them. Regarding the results, PLA/Bioceramic composite scaffolds have shown to be biocompatible and mechanically resistant. Preclinical studies elucidated the ability of the scaffolds to be used as bone grafts, allowing bone growing without adverse reactions. In conclusion, PLA/Bioceramics scaffolds have been demonstrated to be a promising alternative for treating bone defects. Nevertheless, more care should be taken when designing and performing in vivo trials, since the lack of standardization of the processes, which prevents the comparison of the results and reduces the quality of the information. STATEMENT OF SIGNIFICANCE: 3D-printed polylactic acid/bioceramic composite scaffolds have emerged as an alternative to deal with existing limitations when facing bone reconstruction. Since preclinical in vivo studies with animal models represent a mandatory step for clinical translation, the present manuscript analyzed and discussed not only those aspects related to the selection of the bioceramic material, the synthesis of the implants and their characterization. But provides a new approach to understand how the design and perform of clinical trials, as well as the selection of the analysis methods, may affect the obtained results, by covering authors' knowledgebase from veterinary medicine to biomaterial science. Thus, this study aims to systematically review the feasibility of using polylactic acid/bioceramic scaffolds as grafting materials in preclinical trials.


Assuntos
Engenharia Tecidual , Alicerces Teciduais , Ratos , Coelhos , Animais , Engenharia Tecidual/métodos , Poliésteres/farmacologia , Impressão Tridimensional , Regeneração Óssea
17.
Vet Parasitol ; 320: 109973, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37356132

RESUMO

Bovine neosporosis is one of the major causes of reproductive failure in cattle worldwide, and differences in virulence between isolates have been widely shown. However, the molecular basis and mechanisms underlying virulence in Neospora caninum are mostly unknown. Recently, we demonstrated the involvement of NcGRA7 and NcROP40 in the virulence of N. caninum in a pregnant murine model using single knockout mutants in these genes generated by CRISR/Cas9 technology. In this study, the role of these proteins was investigated in two in vitro models using bovine target cells: trophoblast (F3 cell line) and monocyte-derived macrophages (BoMØ). The proliferation capacity of the single knockout mutant parasites was compared to the wild-type strain, the Nc-Spain7 isolate, using both cell populations. For the bovine trophoblast, no differences were observed in the growth of the defective parasites compared to the wild-type strain, neither in the proliferation kinetics nor in the competition assay. However, in naïve BoMØ, a significant decrease in the proliferation capacity of the mutant parasites was observed from 48 h pi onwards. Stimulation of BoMØ with IFN-γ showed a similar inhibition of tachyzoite growth in defective and wild-type strains in a dose-dependent manner. Finally, BoMØ infected with knockout parasites showed higher expression levels of TLR3, which is involved in pathogen recognition. These results suggest that NcGRA7 and NcROP40 may be involved in the manipulation of innate immune defense mechanisms against neosporosis and confirm the usefulness of the BoMØ model for the evaluation of N. caninum virulence mechanisms. However, the specific functions of these proteins remain unknown, opening the way for future research.


Assuntos
Coccidiose , Neospora , Gravidez , Feminino , Bovinos , Animais , Camundongos , Fatores de Virulência/metabolismo , Proteínas de Protozoários/genética , Macrófagos , Virulência , Coccidiose/parasitologia , Coccidiose/veterinária
18.
Scand J Med Sci Sports ; 33(9): 1661-1676, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37322570

RESUMO

OBJECTIVE: This study aimed to assess the residual effects of a 12-week concurrent training program (power training + high-intensity interval training) in older adults with chronic obstructive pulmonary disease (COPD). METHODS: A total of 21 older adults with COPD [intervention (INT), n = 8; control (CON), n = 13; 76.9 ± 6.8 years] were assessed at baseline and 10 months after the completion of the intervention by the short physical performance battery (SPPB), health-related quality of life (EQ-5D-5L), vastus lateralis muscle thickness (MT), peak pulmonary oxygen uptake (peak VO2 ) and peak work rate (Wpeak ), early and late isometric rate of force development (RFD), leg and chest press maximum muscle power (LPmax and CPmax ), and systemic oxidative damage and antioxidant capacity. RESULTS: Compared to baseline, after 10 months of detraining, the INT group presented increased SPPB (∆ = 1.0 point), health-related quality of life (∆ = 0.07 points), early RFD (∆ = 834 N∙s-1 ), LPmax (∆ = 62.2 W), and CPmax (∆ = 16.0 W) (all p < 0.05). In addition, a positive effect was noted in INT compared to CON regarding MT and Wpeak (both p < 0.05). No between-group differences were reported in peak VO2 , late RFD, systemic oxidative damage, and antioxidant capacity from baseline to 10 months after the completion of the intervention (all p > 0.05). CONCLUSIONS: Twelve weeks of concurrent training were enough to ensure improved physical function, health-related quality of life, early RFD and maximum muscle power and to preserve MT and Wpeak but not peak VO2 , late RFD, systemic oxidative damage and antioxidant capacity in the subsequent 10 months of detraining in older adults with COPD.


Assuntos
Treinamento Intervalado de Alta Intensidade , Músculo Esquelético , Doença Pulmonar Obstrutiva Crônica , Treinamento Resistido , Músculo Esquelético/fisiopatologia , Estresse Oxidativo , Antioxidantes/metabolismo , Doença Pulmonar Obstrutiva Crônica/terapia , Humanos , Idoso , Idoso de 80 Anos ou mais , Consumo de Oxigênio , Força Muscular , Desempenho Físico Funcional , Qualidade de Vida , Masculino , Feminino
19.
Int J Parasitol ; 53(9): 505-521, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37207972

RESUMO

Besnoitia besnoiti-infected bulls may develop severe systemic clinical signs and orchitis that may ultimately cause sterility during the acute infection. Macrophages might play a relevant role in pathogenesis of the disease and the immune response raised against B. besnoiti infection. This study aimed to dissect the early interaction between B. besnoiti tachyzoites and primary bovine monocyte-derived macrophages in vitro. First, the B. besnoiti tachyzoite lytic cycle was characterized. Next, dual transcriptomic profiling of B. besnoiti tachyzoites and macrophages was conducted at early infection (4 and 8 h p.i.) by high-throughput RNA sequencing. Macrophages inoculated with heat-killed tachyzoites (MO-hkBb) and non-infected macrophages (MO) were used as controls. Besnoitia besnoiti was able to invade and proliferate in macrophages. Upon infection, macrophage activation was demonstrated by morphological and transcriptomic changes. Infected macrophages were smaller, round and lacked filopodial structures, which might be associated with a migratory phenotype demonstrated in other apicomplexan parasites. The number of differentially expressed genes (DEGs) increased substantially during infection. In B. besnoiti-infected macrophages (MO-Bb), apoptosis and mitogen-activated protein kinase (MAPK) pathways were regulated at 4 h p.i., and apoptosis was confirmed by TUNEL assay. The Herpes simplex virus 1 infection pathway was the only significantly enriched pathway in MO-Bb at 8 h p.i. Relevant DEGs of the Herpes simplex virus 1 infection (IFNα) and the apoptosis pathways (CHOP-2) were also significantly regulated in the testicular parenchyma of naturally infected bulls. Furthermore, the parasite transcriptomic analysis revealed DEGs mainly related to host cell invasion and metabolism. These results provide a deep overview of the earliest macrophage modulation by B. besnoiti that may favour parasite survival and proliferation in a specialized phagocytic immune cell. Putative parasite effectors were also identified.


Assuntos
Doenças dos Bovinos , Coccidiose , Parasitos , Sarcocystidae , Animais , Bovinos , Masculino , Besnoitia , Coccidiose/veterinária , Coccidiose/parasitologia , Sarcocystidae/genética , Doenças dos Bovinos/parasitologia , Macrófagos , Apoptose
20.
FEBS Lett ; 597(10): 1363-1374, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37081294

RESUMO

Polysaccharide-degrading mono-copper lytic polysaccharide monooxygenases (LPMOs) are efficient peroxygenases that require electron donors (reductants) to remain in the active Cu(I) form and to generate the H2 O2 co-substrate from molecular oxygen. Here, we show how commonly used reductants affect LPMO catalysis in a pH-dependent manner. Between pH 6.0 and 8.0, reactions with ascorbic acid show little pH dependency, whereas reactions with gallic acid become much faster at increased pH. These dependencies correlate with the reductant ionization state, which affects its ability to react with molecular oxygen and generate H2 O2 . The correlation does not apply to l-cysteine because, as shown by stopped-flow kinetics, increased H2 O2 production at higher pH is counteracted by increased binding of l-cysteine to the copper active site. The findings highlight the importance of the choice of reductant and pH in LPMO reactions.


Assuntos
Cisteína , Substâncias Redutoras , Substâncias Redutoras/farmacologia , Oxirredução , Cisteína/metabolismo , Polissacarídeos/metabolismo , Oxigenases de Função Mista/química , Concentração de Íons de Hidrogênio , Oxigênio
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