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1.
An Acad Bras Cienc ; 96(1): e20221048, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38597499

RESUMO

The cognitive deficit, which is like Alzheimer's disease and is associated with oxidative damage, may be induced by exposure to streptozotocin. This study aimed to evaluate if the tellurium-containing organocompound, 3j, 5'-arylchalcogeno-3-aminothymidine derivative, interferes with the effects of streptozotocin, as well as to investigate its toxicity in adult mice. Cognitive deficit was induced by two doses of streptozotocin (2.25 mg/kg/day, 48 h interval) intracerebroventricularly. After, the mice were subcutaneously treated with 3j (8.62 mg/kg/day) for 25 days. The effects were assessed by evaluating hippocampal and cortical acetylcholinesterase and behavioral tasks. 3j toxicity was investigated for 10 (0, 21.55, or 43.10 mg/kg/day) and 37 (0, 4.31, or 8.62 mg/kg/day) days by assessing biometric parameters and glucose and urea levels, and alanine aminotransferase activity in blood plasma. 3j exposure did not alter the behavioral alterations induced by streptozotocin exposure. On the other hand, 3j exposure normalized hippocampus acetylcholinesterase activity, which is enhanced by streptozotocin exposure. Toxicity evaluation showed that the administration of 3j for either 10 or 37 days did not cause harmful effects on the biometric and biochemical parameters analyzed. Therefore, 3j does not present any apparent toxicity and reverts acetylcholinesterase activity increase induced by streptozotocin in young adult mice.


Assuntos
Doença de Alzheimer , Transtornos Cognitivos , Camundongos , Animais , Acetilcolinesterase/metabolismo , Estreptozocina/toxicidade , Transtornos Cognitivos/induzido quimicamente , Transtornos Cognitivos/tratamento farmacológico , Estresse Oxidativo , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/tratamento farmacológico , Hipocampo , Modelos Animais de Doenças
2.
Soft Matter ; 18(16): 3107-3119, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35373803

RESUMO

Bone presents an intrinsic ability for self-regeneration and repair, however critical defects and large fractures require invasive and time-consuming clinical interventions. As an alternative to current therapy, bone tissue engineering (BTE) has primarily aimed to recreate the bone microenvironment by delivering key biomolecules and/or by modification of scaffolds to guide cell fate towards the osteogenic lineage or other phenotypes that may benefit the bone regeneration mechanism. Considering that bone cells communicate, in their native microenvironment, through biochemical and physical signals, most strategies fail when considering only chemical, geometrical or mechanical cues. This is not representative of the physiological conditions, where the cells are simultaneously in contact and stimulated by several cues. Therefore, this review explores the synergistic effect of biochemical/physical cues in regulating cellular events, namely cell adhesion, proliferation, osteogenic differentiation, and mineralization, highlighting the importance of the combined modifications for the development of innovative bone regenerative therapies.


Assuntos
Osteogênese , Alicerces Teciduais , Regeneração Óssea , Diferenciação Celular , Sinais (Psicologia) , Osteogênese/genética , Engenharia Tecidual , Alicerces Teciduais/química
3.
Acta Paediatr ; 110(3): 1056-1065, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32780463

RESUMO

AIM: This study evaluated medication poisoning in paediatric patients through a systematic review and a retrospective documentary analysis in a Brazilian toxicological centre. METHODS: The data were systematically collected on PubMed, Scopus and SciELO databases following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. We included epidemiologic and prevalence studies that were published in English or Portuguese from 2013 to 2017 and covered paediatric patients. The retrospective incidence study was carried out in a Brazilian toxicological centre and was a documentary analysis of paediatric medication poisoning cases from 2005 to 2015. RESULTS: The systematic review comprised 13 papers covering 895 206 poisoning cases from six different countries. The main agents of intoxication were analgesics and antihistamines. The eight papers that explored the reasons for the poisonings showed that 93% of those 762 863 cases were accidental. The Brazilian toxicological centre recorded 443 paediatric patients poisoned by medication such as benzodiazepines, analgesics and antibiotics and found that 63.2% were accidental. However, it agreed with the global findings in many other aspects. CONCLUSION: The systematic review showed a sustained number of paediatric medication toxicity cases worldwide and the key findings were broadly reflected by the retrospective study carried out in the Brazilian toxicological centre.


Assuntos
Benzodiazepinas , Intoxicação , Analgésicos , Brasil , Criança , Humanos , Incidência , Intoxicação/epidemiologia , Estudos Retrospectivos
4.
Bioorg Med Chem ; 28(9): 115423, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32205047

RESUMO

Approximately 90% of bladder carcinomas are of the urothelial carcinoma type, which are characterized by high rates of recurrence and predisposition to progress to invasive tumors, representing one of the most costly neoplasms for health systems. Intravesical chemotherapy is a standard for the treatment of non-invasive bladder cancer. However, chemotherapy is usually aggressive and cytotoxic, which increases the death rates caused by cancer. Heterocyclic compounds which exhibit favorable pharmacokinetic and pharmacodynamic properties may enhance drug affinity for a target protein by targeting the treatment. Thus, this work presents the synthesis, characterization, and in vitro biological evaluation of new antioxidant (inhibition of lipid peroxidation, scavenging of free radical DPPH, and thiol peroxidase-like activity) and antiproliferative chalcogenobiotin derivatives and tests them against bladder carcinoma 5637 cells. A prominent response was obtained for the selected compounds, with tellurium biotin derivatives displaying effective antioxidant and antiproliferative activity. The effective compounds also demonstrated no toxicity in in vitro or in vivo studies.


Assuntos
Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Calcogênios/farmacologia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Bexiga Urinária/efeitos dos fármacos , Antineoplásicos/síntese química , Antineoplásicos/química , Antioxidantes/síntese química , Antioxidantes/química , Compostos de Bifenilo/antagonistas & inibidores , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Calcogênios/síntese química , Calcogênios/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Estrutura Molecular , Picratos/antagonistas & inibidores , Relação Estrutura-Atividade , Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/patologia
5.
Cell Biochem Funct ; 32(5): 420-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24619859

RESUMO

This study evaluated the effects of HgCl2 on renal parameters in nonlactating and lactating rats and their pups, as well as the preventive role of ZnCl2 . Rats received 27 mg kg(-1) ZnCl2 for five consecutive days and 5 mg kg(-1) HgCl2 for five subsequent days (s.c.). A decrease in δ-aminolevulinic acid dehydratase (δ-ALA-D) activity in the blood and an increase in urine protein content in renal weight as well as in blood and urine Hg levels were observed in lactating and nonlactating rats from Sal-Hg and Zn-Hg groups. ZnCl2 prevented partially the δ-ALA-D inhibition and the proteinuria in nonlactating rats. Renal Hg levels were increased in all HgCl2 groups, and the ZnCl2 exposure potentiated this effect in lactating rats. Nonlactating rats exposed to HgCl2 exhibited an increase in plasma urea and creatinine levels, δ-ALA-D activity inhibition and histopathological alterations (necrosis, atrophic tubules and collagen deposition) in the kidneys. ZnCl2 exposure prevented the biochemical alterations. Hg-exposed pups showed lower body and renal weight and an increase in the renal Hg levels. In conclusion, mercury-induced nephrotoxicity differs considerably between lactating and nonlactating rats. Moreover, prior exposure with ZnCl2 may provide protection to individuals who get exposed to mercury occupationally or accidentally.


Assuntos
Cloretos/farmacologia , Rim/efeitos dos fármacos , Cloreto de Mercúrio/toxicidade , Compostos de Zinco/farmacologia , Animais , Nitrogênio da Ureia Sanguínea , Peso Corporal/efeitos dos fármacos , Creatinina/sangue , Feminino , Rim/metabolismo , Rim/patologia , Lactação , Mercúrio/sangue , Sintase do Porfobilinogênio/metabolismo , Proteínas/análise , Ratos , Ratos Wistar , Zinco/sangue
6.
Biomolecules ; 14(4)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38672489

RESUMO

Colorectal cancer (CRC) is a leading cause of death worldwide. Conventional therapies are available with varying effectiveness. Acetate, a short-chain fatty acid produced by human intestinal bacteria, triggers mitochondria-mediated apoptosis preferentially in CRC but not in normal colonocytes, which has spurred an interest in its use for CRC prevention/therapy. We previously uncovered that acetate-induced mitochondrial-mediated apoptosis in CRC cells is significantly enhanced by the inhibition of the lysosomal protease cathepsin D (CatD), which indicates both mitochondria and the lysosome are involved in the regulation of acetate-induced apoptosis. Herein, we sought to determine whether mitochondrial function affects CatD apoptotic function. We found that enhancement of acetate-induced apoptosis by CatD inhibition depends on oligomycin A-sensitive respiration. Mechanistically, the potentiating effect is associated with an increase in cellular and mitochondrial superoxide anion accumulation and mitochondrial mass. Our results provide novel clues into the regulation of CatD function and the effect of tumor heterogeneity in the outcome of combined treatment using acetate and CatD inhibitors.


Assuntos
Apoptose , Catepsina D , Neoplasias Colorretais , Mitocôndrias , Oligomicinas , Humanos , Acetatos/farmacologia , Apoptose/efeitos dos fármacos , Catepsina D/metabolismo , Catepsina D/antagonistas & inibidores , Linhagem Celular Tumoral , Respiração Celular/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Neoplasias Colorretais/tratamento farmacológico , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Oligomicinas/farmacologia
7.
Plasmid ; 70(3): 412-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23831558

RESUMO

The goal of this study was to determine and compare the complete genome sequences of three new broad-host-range conjugative plasmids. Plasmids pMLUA1, pMLUA3 and pMLUA4 were previously recovered from estuarine water by exogenous plasmid isolation and ranged in size from ∼55 to 59 kb. Comparative genomics showed that their backbone region was identical to the prototype pKJK5 and other IncP1-ε plasmids captured from soils. The accessory region was inserted between the tra region and parA, and presented the typical IncP-1ε ISPa17 and Tn402-like transposon modules. Nevertheless, new class 1 integrons were identified (In794, carrying aadA5 and In795, carrying qacF5-aadA5), as well as a composite transposon IS26-msr(E)-mph(E)-IS26 carrying genes that confer resistance to macrolides. A new insertion sequence, termed ISUnCu17, was also identified on pMLUA3. The architecture of the accessory regions implies the occurrence of multiple insertions and deletions. These data support the notion that IncP-1 plasmids from the ε subgroup are proficient in the capture of diverse genetic elements, including antibiotic resistance genes, and thus may contribute to the co-selection of several resistance determinants. This study constitutes the first report of completely sequenced IncP-1ε plasmids from water environments, and enhances our understanding of the geographic distribution and genetic diversity of these replicons.


Assuntos
Elementos de DNA Transponíveis , Genômica , Fases de Leitura Aberta , Plasmídeos/química , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Estuários , Variação Genética , Testes de Sensibilidade Microbiana , Filogenia , Plasmídeos/classificação , Análise de Sequência de DNA
8.
Bioengineering (Basel) ; 10(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37370597

RESUMO

Chronic skin wounds, namely diabetic/non-diabetic ulcers and post-surgical wounds, present key obstacles to achieve anatomic and functional regeneration within approximately 3 months [...].

9.
Front Biosci (Elite Ed) ; 15(4): 23, 2023 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-38163934

RESUMO

Oral diseases affect over three billion people worldwide, making it one of the most common infections. Recent studies show that one approach to reducing the risk of chronic infections, such as caries, gingivitis, periodontitis, and halitosis, is to control the ecology of the oral microbiome instead of completely removing both the harmful and beneficial microorganisms. This is based on the knowledge that oral diseases are not caused by a single pathogen but rather by a shift in the homeostasis of the entire microbiota, a process known as dysbiosis. Consequently, it is of the utmost importance to implement strategies that are able to prevent and control oral dysbiosis to avoid serious complications, including heart, lung, and other systemic diseases. Conventional treatments include the use of antibiotics, which further disrupt the equilibrium in the oral microbiota, together with the mechanical removal of the decayed cavity area following its formation. Therefore, it is imperative to implement alternative strategies with the potential to overcome the disadvantages of the current therapy, namely, the use of broad-spectrum antibiotics. In this sense, probiotics and postbiotics have received particular attention since they can modulate the oral microbiota and decrease the dysbiotic rate in the oral cavity. However, their mechanisms of action need to be addressed to clarify and drive their possible applications as preventive strategies. In this sense, this review provides an overview of the potential of probiotics and postbiotics, focusing on their antimicrobial and antibiofilm activities as well as their ability to modulate the inflammatory response. Finally, it also showcases the main advantages and disadvantages of orodispersible films-a promising delivery mechanism for both probiotics and postbiotics to target oral dysbiosis.


Assuntos
Microbiota , Periodontite , Humanos , Disbiose/prevenção & controle , Microbiota/fisiologia , Antibacterianos/uso terapêutico
10.
Front Neurol ; 14: 1196585, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37396775

RESUMO

Background: Anodal transcranial direct current stimulation (tDCS) over the primary motor cortex and cerebellum is gaining prominence in the literature due to its potential to favor learning and motor performance. If administered during motor training, tDCS is capable of increasing the effect of training. Considering the motor impairment presented by children with Autism Spectrum Disorders (ASD), atDCS applied during motor training may contribute to the rehabilitation of these children. However, it is necessary to examine and compare the effects of atDCS over the motor cortex and the cerebellum on the motor skills of children with ASD. This information may benefit future clinical indications of tDCS for rehabilitation of children with ASD. The aim of the proposed study is to determine whether anodal tDCS over the primary motor cortex and cerebellum can enhance the effects of gait training and postural control on motor skills, mobility, functional balance, cortical excitability, cognitive aspects and behavioral aspects in children with ASD. Our hypothesis is the active tDCS combined with motor training will enhance the performance of the participants in comparison to sham tDCS. Methods and design: A randomized, sham-controlled, double-blind clinical trial will be conducted involving 30 children with ASD that will be recruited to receive ten sessions of sham or ten sessions of active anodal tDCS (1 mA, 20 min) over the primary motor cortex or cerebellun combined with motor training. The participants will be assessed before as well as one, four and eight weeks after the interventions. The primary outcome will be gross and fine motor skills. The secondary outcomes will be mobility, functional balance, motor cortical excitability, cognitive aspects and behavioral aspects. Discussion: Although abnormalities in gait and balance are not primary characteristics of ASD, such abnormalities compromise independence and global functioning during the execution of routine activities of childhood. If demonstrated that anodal tDCS administered over areas of the brain involved in motor control, such as the primary motor cortex and cerebellum, can enhance the effects of gait and balance training in only ten sessions in two consecutive weeks, the clinical applicability of this stimulation modality will be expanded as well as more scientifically founded.Clinical trial registration February 16, 2023 (https://ensaiosclinicos.gov.br/rg/RBR-3bskhwf).

11.
Antonie Van Leeuwenhoek ; 101(4): 819-35, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22258199

RESUMO

Bacterioneuston may play a key role in water-air exchange of gases and in processing organic matter and pollutants that accumulate at the sea-surface microlayer (SML). However, the phylogenetic diversity of bacterioneuston has been poorly characterized. We analyzed 24 samples each from the SML and underlying water (UW) at three sites in the Ria de Aveiro estuary, Portugal. Cultivation and culture-independent techniques were used to compare bacterioneuston and bacterioplankton. Culturable heterotrophic bacteria were enriched in the SML. The culturable community was dominated by Psychrobacter and Acinetobacter. The presence of high numbers of Psychrobacter was a notable result. Differences were confined to a few genera overrepresented in UW samples (Kocuria, Agrococcus and Vibrio). 16S rDNA DGGE profiles were highly stable in terms of number and position of bands between sampling sites and dates but cluster analysis revealed a slight tendency for grouping according to sampled layer. SML-specific DGGE bands affiliated with Actinobacteria, Cyanobacteria, Gammaproteobacteria and Bacteroidetes. Low similarity between nucleotide sequences of DGGE-bands and previously reported sequences suggest the occurrence of SML-specific populations. Enrichment of SML for Pseudomonas and Aeromonas was questioned and the diversity of both communities was analyzed. Consistent differences between SML and UW aeromonads communities were not identified. In terms of Pseudomonas, a culturable operational taxonomic unit was consistently overrepresented within SML samples. Taken together, our results indicate that the similarity between SML and UW communities depends on spatial and temporal factors.


Assuntos
Bactérias/classificação , Bactérias/isolamento & purificação , Biota , Microbiologia da Água , Bactérias/genética , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Eletroforese em Gel de Gradiente Desnaturante , Dados de Sequência Molecular , Filogenia , Portugal , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Poluentes Químicos da Água/metabolismo
12.
BMC Pediatr ; 12: 53, 2012 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-22591446

RESUMO

BACKGROUND: The use of botulinum toxin A (BT-A) for the treatment of lower limb spasticity is common in children with cerebral palsy (CP). Following the administration of BT-A, physical therapy plays a fundamental role in potentiating the functionality of the child. The balance deficit found in children with CP is mainly caused by muscle imbalance (spastic agonist and weak antagonist). Neuromuscular electrical stimulation (NMES) is a promising therapeutic modality for muscle strengthening in this population. The aim of the present study is to describe a protocol for a study aimed at analyzing the effects of NMES on dorsiflexors combined with physical therapy on static and functional balance in children with CP submitted to BT- A. METHODS/DESIGN: Protocol for a prospective, randomized, controlled trial with a blinded evaluator. Eligible participants will be children with cerebral palsy (Levels I, II and III of the Gross Motor Function Classification System) between five and 12 years of age, with independent gait with or without a gait-assistance device. All participants will receive BT-A in the lower limbs (triceps surae). The children will then be randomly allocated for either treatment with motor physical therapy combined with NMES on the tibialis anterior or motor physical therapy alone. The participants will be evaluated on three occasions: 1) one week prior to the administration of BT-A; 2) one week after the administration of BT-A; and 3) four months after the administration of BT-A (end of intervention). Spasticity will be assessed by the Modified Ashworth Scale and Modified Tardieu Scale. Static balance will be assessed using the Medicapteurs Fusyo pressure platform and functional balance will be assessed using the Berg Balance Scale. DISCUSSION: The aim of this protocol study is to describe the methodology of a randomized, controlled, clinical trial comparing the effect of motor physical therapy combined with NMES on the tibialis anterior muscle or motor physical therapy alone on static and functional balance in children with CP submitted to BT-A in the lower limbs. This study describes the background, hypotheses, methodology of the procedures and measurement of the results. TRIAL REGISTRATION: RBR5qzs8h.


Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Paralisia Cerebral/terapia , Terapia por Estimulação Elétrica , Fármacos Neuromusculares/uso terapêutico , Equilíbrio Postural , Tornozelo , Paralisia Cerebral/fisiopatologia , Criança , Pré-Escolar , Protocolos Clínicos , Terapia Combinada , Terapia por Exercício , Humanos , Músculo Esquelético/fisiologia , Estudos Prospectivos , Método Simples-Cego , Resultado do Tratamento
13.
Tissue Eng Part B Rev ; 28(2): 379-392, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-33683146

RESUMO

The repair process of bone fractures is a complex biological mechanism requiring the recruitment and in situ functionality of stem/stromal cells from the bone marrow (BM). BM mesenchymal stem/stromal cells have been widely explored in multiple bone tissue engineering applications, whereas the use of hematopoietic stem cells (HSCs) has been poorly investigated in this context. A reasonable explanation is the fact that the role of HSCs and their combined effect with other elements of the hematopoietic niches in the bone-healing process is still elusive. Therefore, in this review we intend to highlight the influence of HSCs in the bone repair process, mainly through the promotion of osteogenesis and angiogenesis at the bone injury site. For that, we briefly describe the main biological characteristics of HSCs, as well as their hematopoietic niches, while reviewing the biomimetic engineered BM niche models. Moreover, we also highlighted the role of HSCs in translational in vivo transplantation or implantation as promoters of bone tissue repair. Impact statement The ability of bone to natural self-heal depends on the size and stabilization level of the tissue fracture, and it is impaired in several pathophysiological conditions. Considering that the available treatment options have demonstrated limited regenerative performance, the hematopoietic stem cells (HSCs) co-cultured in different tissue engineering strategies have emerged as a powerful tool to promote effective bone regeneration and healing. Here, we reviewed the most important biomimetic bone-marrow hematopoietic niches and showed the regenerative potential of these cells, both in vitro and in translational in vivo transplantation/implantation approaches. This knowledge encourages the development of new HSC-related bone regenerative therapies.


Assuntos
Células-Tronco Hematopoéticas , Células-Tronco Mesenquimais , Medula Óssea , Células da Medula Óssea , Regeneração Óssea , Humanos
14.
Toxics ; 10(11)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36355967

RESUMO

Pesticide exposure has deleterious effects on human health and development; however, no review has been conducted on human exposure to pesticides and the risk of congenital malformations and cancer in the same cohort. We systematically reviewed the evidence for this relationship following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Four databases, namely, PubMed, Scopus, Cochrane Library, and BVS, were searched for studies deposited till July 2020 that examined the influence of pesticide exposure on congenital malformations and cancer outcomes in the same cohort. Seven studies were systematically included in this review. Among these, four were case-control studies, two were cross-sectional studies, and one was a longitudinal cohort study. The sources of contamination were food, water, or exposure during agricultural work. A link between the occurrence of cancer, congenital malformations, and exposure to pesticides was observed in most studies.

15.
Acta Biomater ; 149: 167-178, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35811072

RESUMO

Recreating the biological complexity of living bone marrow (BM) in a single in vitro strategy has faced many challenges. Most bioengineered strategies propose the co-culture of BM cellular components entrapped in different matrices limiting their migration and self-organization capacity or in open scaffolds enabling their escaping. We propose a methodology for fabricating a "human bone marrow-in-a-liquefied-capsule" to overcome these challenges, embracing the most important BM components in a single platform. Since free dispersion of the cells within the BM is an essential feature to maintain their in vivo properties, this platform provides a liquefied environment for the encapsulated cells to move freely and self-organize. Inside liquefied capsules, an engineered endosteal niche (eEN) is co-cultured with human umbilical cord cells, including endothelial cells and hematopoietic stem and progenitor cells (HSPCs). Two different human-like BM niches were recreated under static and dynamic systems. Although the culture of the engineered BM capsules (eBMC) in these different environments did not change the structural and compositional features of the BM niches, the biophysical stimulation potentiated the cellular intercommunication and the biomolecules secretion, demonstrating an enhanced in vitro bio performance. Moreover, while the eBMC without HSPCs provided the secretion of hematopoietic supportive factors, the presence of these cells recapitulated more closely the biological complexity of the native BM niches. This functional eBMC approach is an innovative platform capable of investigating several components and interactions of BM niches and how they regulate BM homeostasis and hematopoiesis. STATEMENT OF SIGNIFICANCE: The recapitulation of the multifaceted bone marrow (BM) microenvironment under in vitro conditions has gained intensive recognition to understand the intrinsic complexity of the native BM. While conventional strategies do not recapitulate the BM osteovascular niches nor give the cellular components a free movement, we report for the first time the development of human bone marrow-in-a-liquefied-capsule to overcome such limitations. Our engineered BM capsules (eBMC) partially mimic the complex structure, composition, and spatial organization of the native osteovascular niches present in the BM. This strategy offers a platform with physiological relevance to exploit the niches' components/networks and how they regulate the hematopoiesis and the initiation/progression of various BM-related pathologies.


Assuntos
Medula Óssea , Nicho de Células-Tronco , Bioengenharia , Células da Medula Óssea , Células Endoteliais , Células-Tronco Hematopoéticas , Humanos
16.
Curr Opin Insect Sci ; 52: 100923, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35462063

RESUMO

Toxic metals, such as mercury (Hg), lead (Pb), cadmium (Cd), and copper (Cu), are widespread in the biosphere, and human activities have contributed to their continuous release into the ecosystems. Metal-induced toxicity has been extensively studied in mammals; however, the effects of these metals on insects' behavior have been explored to far lesser degree. As the main mechanism of toxicity, the cationic metals, explored in this review, have high affinity for thiol-containing molecules, disrupting the function of several proteins and low-molecular-weight thiol-containing molecules. Existing literature has corroborated that Hg, Pb, Cd, and Cu can disrupt locomotor and mating behaviors, but their effects on insects' memory and learning have yet to be fully characterized. Though field studies on metal-induced toxicity in insects are limited, results from Drosophila melanogaster as an experimental model suggest that insects living in contaminated environments can have behavioral foraging and reproductive deficits, which may cause population decline. In this review, we address the interaction between metals and endogenous thiol groups, with emphasis on alterations in insect behavior.


Assuntos
Cádmio , Mercúrio , Animais , Drosophila melanogaster , Ecossistema , Humanos , Chumbo , Mamíferos , Compostos de Sulfidrila
17.
Toxics ; 10(11)2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36355955

RESUMO

The aim of this study was to investigate the effects of inorganic mercury (Hg2+) exposure on biochemical parameters of dams and their offspring exposed to metal in drinking water. Female Wistar rats were exposed to 0, 10, and 50 µg Hg2+/mL (as HgCl2) for 42 days corresponding to gestational (21 days) and lactational (21 days) periods. The offspring were sacrificed on postnatal days 10, 20, 30, and 40. Dams exposed to Hg2+ presented a decrease in water intake in gestation [total: F(2,19) = 15.84; p ≤ 0.0001; daily: F(2,21) = 12.71; p = 0.0002] and lactation [total: F(2,19) = 4.619; p = 0.024; daily: F(2,21) = 5.309; p = 0.0136] without alteration in food intake. Dams exposed to 50 µg Hg2+/mL had an increase in kidney total [F(2,21) = 8.081; p = 0.0025] and relative [F(2,21) = 14.11; p = 0.0001] weight without changes in biochemical markers of nephrotoxicity. Moreover, dams had an increase in hepatic [F(2,10) = 3.847; p = 0.0577] and renal [F(2,11) = 6.267; p = 0.0152] metallothionein content concomitantly with an increase in renal Hg levels after Hg2+ exposure. Regarding offspring, the exposure to Hg2+in utero and breast milk increased the relative liver [F(2,18) = 5.33; p = 0.0152] and kidney [F(2,18) = 3.819; p = 0.0415] weight only on the postnatal day 40. In conclusion, dams were able to handle the Hg2+ avoiding the classic Hg2+ toxic effects as well as protecting the offspring. We suggest that this protection is related to the hepatic and renal metallothionein content increase.

18.
Environ Pollut ; 292(Pt A): 118316, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34648837

RESUMO

The aim of this study was to evaluate the effects of Pb exposure on full-scale IQ score in pediatric subjects. Following PRISMA guidelines, the data from January 2010 to April 2020 were systematically searched and collected on electronic databases (PubMed, Scopus, and Embase). The eligibility criteria included cross-sectional, cohort, and case-control studies that were published in English, from 2010 to 2020, that analyzed the blood Pb levels of pediatric subjects (0-19 years) and possible changes in the full-scale IQ score. In this study, 2174 scientific papers were collected from three electronic databases. From those, 726 were duplicates and 1421 were excluded because they did not meet the eligibility criteria, resulting in a total of 27 papers, from which, seven were used to perform the meta-analysis. The 27 scientific papers systematically selected for this study were separated by the country where the study was realized in developed and underdeveloped/developing countries. In the underdeveloped/developing countries the blood Pb levels are higher and showed a greater variation (1.30-11.66 µgPb/dL of blood) than in countries with higher development index (0.57-4.80 µgPb/dL of blood). The full-scale IQ score are inversely proportional to the blood Pb values, and it is possible to see that in the underdeveloped/developing countries the full-scale IQ score showed lower values and greater variation (59.2-111) compared to the individuals from developed countries (91.9-114.5). In conclusion, it was observed that blood Pb levels alter the full-scale IQ score. Thus, policies for the prevention of environmental contamination and the reduction of Pb exposure must be taken, mainly, in underdeveloped/developing countries.


Assuntos
Países em Desenvolvimento , Inteligência , Criança , Estudos de Coortes , Estudos Transversais , Poluição Ambiental , Humanos
19.
Clin Neurophysiol ; 143: 154-165, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36115809

RESUMO

OBJECTIVE: Although relatively costly and non-scalable, non-invasive neuromodulation interventions are treatment alternatives for neuropsychiatric disorders. The recent developments of highly-deployable transcranial electric stimulation (tES) systems, combined with mobile-Health technologies, could be incorporated in digital trials to overcome methodological barriers and increase equity of access. The study aims are to discuss the implementation of tES digital trials by performing a systematic scoping review and strategic process mapping, evaluate methodological aspects of tES digital trial designs, and provide Delphi-based recommendations for implementing digital trials using tES. METHODS: We convened 61 highly-productive specialists and contacted 8 tES companies to assess 71 issues related to tES digitalization readiness, and processes, barriers, advantages, and opportunities for implementing tES digital trials. Delphi-based recommendations (>60% agreement) were provided. RESULTS: The main strengths/opportunities of tES were: (i) non-pharmacological nature (92% of agreement), safety of these techniques (80%), affordability (88%), and potential scalability (78%). As for weaknesses/threats, we listed insufficient supervision (76%) and unclear regulatory status (69%). Many issues related to methodological biases did not reach consensus. Device appraisal showed moderate digitalization readiness, with high safety and potential for trial implementation, but low connectivity. CONCLUSIONS: Panelists recognized the potential of tES for scalability, generalizability, and leverage of digital trials processes; with no consensus about aspects regarding methodological biases. SIGNIFICANCE: We further propose and discuss a conceptual framework for exploiting shared aspects between mobile-Health tES technologies with digital trials methodology to drive future efforts for digitizing tES trials.


Assuntos
Telemedicina , Estimulação Transcraniana por Corrente Contínua , Consenso , Estimulação Elétrica , Humanos , Estimulação Transcraniana por Corrente Contínua/métodos
20.
BMC Pulm Med ; 11: 57, 2011 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-22151802

RESUMO

BACKGROUND: Obstructive sleep apnea (OSA) is a respiratory disease characterized by the collapse of the extrathoracic airway and has important social implications related to accidents and cardiovascular risk. The main objective of the present study was to investigate whether the drop in expiratory flow and the volume expired in 0.2 s during the application of negative expiratory pressure (NEP) are associated with the presence and severity of OSA in a population of professional interstate bus drivers who travel medium and long distances. METHODS/DESIGN: An observational, analytic study will be carried out involving adult male subjects of an interstate bus company. Those who agree to participate will undergo a detailed patient history, physical examination involving determination of blood pressure, anthropometric data, circumference measurements (hips, waist and neck), tonsils and Mallampati index. Moreover, specific questionnaires addressing sleep apnea and excessive daytime sleepiness will be administered. Data acquisition will be completely anonymous. Following the medical examination, the participants will perform a spirometry, NEP test and standard overnight polysomnography. The NEP test is performed through the administration of negative pressure at the mouth during expiration. This is a practical test performed while awake and requires little cooperation from the subject. In the absence of expiratory flow limitation, the increase in the pressure gradient between the alveoli and open upper airway caused by NEP results in an increase in expiratory flow. DISCUSSION: Despite the abundance of scientific evidence, OSA is still underdiagnosed in the general population. In addition, diagnostic procedures are expensive, and predictive criteria are still unsatisfactory. Because increased upper airway collapsibility is one of the main determinants of OSA, the response to the application of NEP could be a predictor of this disorder. With the enrollment of this study protocol, the expectation is to encounter predictive NEP values for different degrees of OSA in order to contribute toward an early diagnosis of this condition and reduce its impact and complications among commercial interstate bus drivers. TRIAL REGISTRATION: Registro Brasileiro de Ensaios Clinicos (local acronym RBEC) [Internet]: Rio de Janeiro (RJ): Instituto de Informaçao Cientifica e Tecnologica em Saude (Brazil); 2010 - Identifier RBR-7dq5xx. Cross-sectional study on efficacy of negative expiratory pressure test proposed as screening for obstructive sleep apnea syndrome among commercial interstate bus drivers; 2011 May 31 [7 pages]. Available from http://www.ensaiosclinicos.gov.br/rg/RBR-7dq5xx/.


Assuntos
Doenças Cardiovasculares/epidemiologia , Síndrome Metabólica/epidemiologia , Veículos Automotores , Apneia Obstrutiva do Sono/diagnóstico , Adulto , Estudos Transversais , Humanos , Masculino , Programas de Rastreamento , Observação , Polissonografia , Reprodutibilidade dos Testes , Projetos de Pesquisa , Apneia Obstrutiva do Sono/epidemiologia , Espirometria , Inquéritos e Questionários
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