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2.
Neurology ; 103(5): e209778, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39151103

RESUMO

BACKGROUND AND OBJECTIVES: Stroke mortality is more common in low-income and middle-income nations such as Mexico. Prognosis data typically rely on short-term hospital follow-ups, revealing high mortality rates due to systemic complications and early recurrence. We aim to explore stroke's long-term impact by examining all-cause and cause-specific mortality. METHODS: We analyzed data from the Mexico City Prospective Study (1998-2004) with known mortality outcomes until December 2022. Baseline variables were compared between participants who had stroke and nonstroke participants. Cox proportional hazard regression assessed each variable's contribution to overall mortality. Subsequent analysis within the stroke subgroup aimed to identify unique risk factors of mortality, using Cox regression models adjusted for age, sex, and time since stroke. RESULTS: Among 145,537 eligible participants, 1,492 (1.0%) had a history of stroke. Participants who had stroke were older (57.58 vs 50.16, p < 0.001); had lower mean weekly income ($108.24 vs $176.14, p < 0.001); had higher alcohol intake and smoking frequency; and had more frequent comorbidities such as hypertension (48.9 vs 19.3%, p < 0.001), diabetes (23.4 vs 12.9%, p < 0.001), and ischemic heart disease (5.4 vs 1.0%, p < 0.001). They had a significantly increased risk of death from any cause (hazard ratio [HR] 2.59, 95% CI 2.37-2.83, p < 0.001). Deceased participants with stroke were more likely to be male, with a higher prevalence of diabetes, hypertension, and abnormal waist-hip index. Stroke increased the risk of death from cardiac (HR 3.56, 95% CI 3.02-4.19, p < 0.001), renal (HR 2.05, 95% CI 1.58-2.66, p < 0.001), and pulmonary (HR 2.29, 95% CI 1.79-2.92, p < 0.001) causes. DISCUSSION: This study confirms stroke's association with higher mortality rates, especially from cardiac, renal, and pulmonary causes in Mexico. It underscores the elevated prevalence of cardiovascular comorbidities and adverse socioeconomic profiles among participants who had stroke and those who died with a history of stroke.


Assuntos
Acidente Vascular Cerebral , Humanos , México/epidemiologia , Masculino , Feminino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/epidemiologia , Idoso , Estudos Prospectivos , Fatores de Risco , Causas de Morte , Adulto , Modelos de Riscos Proporcionais , Comorbidade
3.
Cell Mol Life Sci ; 81(1): 329, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090270

RESUMO

Decidualisation of the endometrium is a key event in early pregnancy, which enables embryo implantation. Importantly, the molecular processes impairing decidualisation in obese mothers are yet to be characterised. We hypothesise that impaired decidualisation in obese mice is mediated by the upregulation of leptin modulators, the suppressor of cytokine signalling 3 (SOCS3) and the protein tyrosine phosphatase non-receptor type 2 (PTPN2), together with the disruption of progesterone (P4)-signal transducer and activator of transcription (STAT3) signalling. After feeding mice with chow diet (CD) or high-fat diet (HFD) for 16 weeks, we confirmed the downregulation of P4 and oestradiol (E2) steroid receptors in decidua from embryonic day (E) 6.5 and decreased proliferation of stromal cells from HFD. In vitro decidualised mouse endometrial stromal cells (MESCs) and E6.5 deciduas from the HFD showed decreased expression of decidualisation markers, followed by the upregulation of SOCS3 and PTPN2 and decreased phosphorylation of STAT3. In vivo and in vitro leptin treatment of mice and MESCs mimicked the results observed in the obese model. The downregulation of Socs3 and Ptpn2 after siRNA transfection of MESCs from HFD mice restored the expression level of decidualisation markers. Finally, DIO mice placentas from E18.5 showed decreased labyrinth development and vascularisation and fetal growth restricted embryos. The present study revealed major defects in decidualisation in obese mice, characterised by altered uterine response to E2 and P4 steroid signalling. Importantly, altered hormonal response was associated with increased expression of leptin signalling modulators SOCS3 and PTPN2. Elevated levels of SOCS3 and PTPN2 were shown to molecularly affect decidualisation in obese mice, potentially disrupting the STAT3-PR regulatory molecular hub.


Assuntos
Decídua , Retardo do Crescimento Fetal , Leptina , Placenta , Transdução de Sinais , Animais , Feminino , Camundongos , Gravidez , Decídua/metabolismo , Decídua/patologia , Dieta Hiperlipídica/efeitos adversos , Retardo do Crescimento Fetal/metabolismo , Retardo do Crescimento Fetal/patologia , Leptina/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/metabolismo , Obesidade/patologia , Placenta/metabolismo , Progesterona/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 2/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 2/genética , Fator de Transcrição STAT3/metabolismo , Células Estromais/metabolismo , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Proteína 3 Supressora da Sinalização de Citocinas/genética
4.
Water Res ; 263: 122156, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39121561

RESUMO

Sulfidogenesis is a promising technology for the selective recovery of chalcophile bulk metals (e.g. Cu, Zn, and Co) from metal-contaminated waters such as acid mine drainage (AMD) and metallurgy waste streams. The use of elemental sulfur (S0) instead of sulfate (SO42-) as electron acceptor reduces electron donor requirements four-fold, lowering process costs, and expanding the range of operating conditions to a more acidic pH. We previously reported autotrophic S0 reduction using an industrial mesophilic granular sludge as inoculum under thermoacidophilic conditions. Here, we examined the effect of pH on the S0 reduction performance of the same inoculum, in a gas-lift reactor run at 30°C under neutral (pH 6.9) and acidic (pH 3.8) conditions, continuously fed with mineral media and H2 and CO2. Steady-state volumetric sulfide production rates (VSPR) dropped 2.5-fold upon transition to acidic pH, from 1.79 ± 0.18 g S2-·L-1·d-1 to 0.71 ± 0.07 g S2-·L-1·d-1. Microbial community composition was analyzed using 16S rRNA gene amplicon sequencing. At neutral pH (6.9), the high relative abundance of the S0-reducing genus Sulfurospirillum, previously known only for heterotrophic members, combined with the presence of Acetobacterium and detection of acetate, suggests an important role for heterotrophic S0 reduction facilitated by acetogenesis. Conversely, at acidic pH (3.9), S0 reduction appeared autotrophic, as indicated by the high relative abundance of Desulfurella.

5.
BMC Prim Care ; 25(1): 282, 2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39097714

RESUMO

BACKGROUND: Due to the significant increase in the prevalence of food-related diseases, the value that physicians place on nutritional advice may have implications for patient treatment. The objective of this study was to evaluate the perception of the importance of nutritional intervention among physicians in the Universidad San Francisco de Quito's (USFQ) healthcare system. METHODS: This cross-sectional study employed a telephone survey administered to a subset of all medical doctors (MDs) working in the healthcare system clinics of USFQ between 2021 and 2022. Study participants were recruited through voluntary response sample from a complete list of 253 MD. The single time questionnaire consisted of a 22-item validated survey in which attitudes, self-perceived capacity, and knowledge about nutrition ofmedical doctors were evaluated. Data was analyzed using descriptive statistics, two-sided t test, bivariate associations and linear and logistic regressions. RESULTS: 136 MDs completed the survey yielding a response rate of 54%. Our analysis grouped participants into clinical (CE) and non-clinical specialties, hereafter referred to as surgical MDs. While a higher percentage of physicians in CE are confident in their ability to provide examples of recommended food portions based on national or international guidelines, 1 in 10 do not know how to use and interpret BMI or waist circumference, and around 1 in 3 do not know how many calories there are in one gram of fat, protein, or carbohydrates, and their basic metabolic functions. Almost all survey participants believe MDs can have an impact on the eating behavior of a patient if time is used to discuss the problem, however, almost half of survey participants believe nutrition counseling is not an effective use of time. CONCLUSION: It is important to explore the perceptions and self-confidence of physicians around nutrition related issues. Our results demonstrated that nearly 1 in 4 surgical MDs do not feel capable of recognizing nutritional risk in patients, which highlights the essentiality of physicians having an updated understanding of basic nutrition principles. Future research should examine how commonly MDs refer patients to nutritionists/dietitians, as well as strategies for improving physician knowledge on basic nutrition concepts.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Humanos , Estudos Transversais , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Médicos/psicologia , Atitude do Pessoal de Saúde , Inquéritos e Questionários , São Francisco , Cirurgiões/psicologia , Competência Clínica
6.
ISME J ; 18(1)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-39030685

RESUMO

Climate change-driven sea level rise threatens freshwater ecosystems and elicits salinity stress in microbiomes. Methane emissions in these systems are largely mitigated by methane-oxidizing microorganisms. Here, we characterized the physiological and metabolic response of freshwater methanotrophic archaea to salt stress. In our microcosm experiments, inhibition of methanotrophic archaea started at 1%. However, during gradual increase of salt up to 3% in a reactor over 12 weeks, the culture continued to oxidize methane. Using gene expression profiles and metabolomics, we identified a pathway for salt-stress response that produces the osmolyte of anaerobic methanotrophic archaea: N(ε)-acetyl-ß-L-lysine. An extensive phylogenomic analysis on N(ε)-acetyl-ß-L-lysine-producing enzymes revealed that they are widespread across both bacteria and archaea, indicating a potential horizontal gene transfer and a link to BORG extrachromosomal elements. Physicochemical analysis of bioreactor biomass further indicated the presence of sialic acids and the consumption of intracellular polyhydroxyalkanoates in anaerobic methanotrophs during salt stress.


Assuntos
Archaea , Água Doce , Metano , Osmorregulação , Filogenia , Estresse Salino , Metano/metabolismo , Água Doce/microbiologia , Anaerobiose , Archaea/metabolismo , Archaea/genética , Archaea/classificação , Oxirredução
7.
Curr Opin Biotechnol ; 88: 103164, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38964081

RESUMO

The sulfur cycle is a complex biogeochemical cycle characterized by the high variability in the oxidation states of sulfur. While sulfur is essential for life processes, certain sulfur compounds, such as hydrogen sulfide, are toxic to all life forms. Micro-organisms facilitate the sulfur cycle, playing a prominent role even in extreme environments, such as soda lakes, acid mine drainage sites, hot springs, and other harsh habitats. The activity of these micro-organisms presents unique opportunities for mitigating sulfur-based pollution and enhancing the recovery of sulfur and metals. This review highlights the application of sulfur-oxidizing and -reducing micro-organisms in environmental biotechnology through three illustrative examples. Additionally, it discusses the challenges, recent trends, and prospects associated with these applications.


Assuntos
Biotecnologia , Enxofre , Biotecnologia/métodos , Enxofre/metabolismo , Oxirredução , Bactérias/metabolismo , Biodegradação Ambiental
8.
Sci Rep ; 14(1): 17702, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39085257

RESUMO

Hydrogen sulfide (H2S) in environments with temperatures below 100 °C is generally assumed to be of microbial origin, while abiotic H2S production is typically restricted to higher temperatures (T). In this study, we report an abiotic process for sulfidogenesis through the reduction of elemental sulfur (S0) by hydrogen (H2), mediated by pyrite (FeS2). The process was investigated in detail at pH 4 and 80 °C, but experimental conditions ranged between 40 and 80 °C and pH 4-6. The experiments were conducted with H2 as reducing molecule, and µm-sized spherical (but not framboidal) pyrite particles that formed in situ from the H2S, S0 and Fe2+ present in the experiments. Fe monosulfides, likely mackinawite, were identified as potential pyrite precursors. The absence of H2 production in controls, combined with geochemical modelling, suggests that pyrite formation occurred through the polysulfide pathway, which is unexpected under acidic conditions. Most spherical aggregates of authigenic pyrite were composed of nanometric, acicular crystals oriented in diverse directions, displaying varying degrees of organization. Although it was initially hypothesized that the catalytic properties were related to the surface structure, commercially sourced, milled pyrite particles (< 50 µm) mediated H2S production at comparable rates. This suggests that the catalytic properties of pyrite depend on particle size rather than surface structure, requiring pyrite surfaces to act as electron shuttles between S0 and H2.

9.
PLoS One ; 19(6): e0296913, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38870173

RESUMO

Surgical oncology often requires the use of contrast-enhanced cross-sectional imaging preoperatively to characterize solitary tumours and identify sentinel lymph nodes. Intraoperative optical guidance can effectively aid tissue-sparing tumour excision and locate sentinel lymph nodes. Nanotrast-CF800 (CF800) is a novel dual-modality contrast agent, which co-encapsulates iohexol and indocyanine green (ICG) within a liposomal nanoparticle. It was developed for preoperative and intraoperative imaging of solitary tumours and sentinel lymph node mapping and its efficacy has been demonstrated in preclinical animal models (Zheng et al. 2015). The objective of this study is to evaluate the safety profile of CF800 following intravenous administration in healthy dogs. Six research dogs were randomized into two groups. Group 1 received a low dose (1 mL/kg) and group 2 received a high dose (5 mL/kg). Dogs were placed under general anesthesia and a continuous rate infusion of CF800 was administered based on group allocation. Physiologic parameters including heart rate, respiratory rate, direct arterial blood pressure, cardiac output, and temperature were measured at set time points. Plasma concentrations of iohexol, ICG, and histamine were measured at set time points. Dogs underwent whole body computed tomography scans pre-injection, 2-, and 7-days post-injection (p.i.). Contrast enhancement was measured in select organ systems and great vessels at each time point. There were no significant changes in physiologic parameters following IV infusion of CF800 in all dogs. Plasma iohexol and ICG concentrations peaked at 1 day p.i., while histamine concentrations peaked at 30 minutes p.i. Significant contrast enhancement was noted within the liver, heart, aorta, and caudal vena cava on day 2 p.i., which was significantly different compared to baseline. Prolonged contrast retention within the liver was identified. Intravenous administration of CF800 was safe to use in healthy dogs with no significant systemic adverse effects.


Assuntos
Meios de Contraste , Verde de Indocianina , Iohexol , Nanopartículas , Neoplasias , Animais , Cães , Nanopartículas/química , Meios de Contraste/administração & dosagem , Iohexol/administração & dosagem , Verde de Indocianina/química , Verde de Indocianina/administração & dosagem , Neoplasias/cirurgia , Neoplasias/diagnóstico por imagem , Cirurgia Assistida por Computador/métodos , Feminino , Masculino
10.
Curr Heart Fail Rep ; 21(4): 367-378, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38861129

RESUMO

PURPOSE OF REVIEW: Limited research has been conducted on sex disparities in heart transplant (HT). The aim of this review is to analyse the available evidence on the influence of sex and gender-related determinants in the entire HT process, as well as to identify areas for further investigation. RECENT FINDINGS: Although women make up half of the population affected by heart failure and related mortality, they account for less than a third of HT recipients. Reasons for this inequality include differences in disease course, psychosocial factors, concerns about allosensitisation, and selection or referral bias in female patients. Women are more often listed for HT due to non-ischaemic cardiomyopathy and have a lower burden of cardiovascular risk factors. Although long-term prognosis appears to be similar for both sexes, there are significant disparities in post-HT morbidity and causes of mortality (noting a higher incidence of rejection in women and of malignancy and cardiac allograft vasculopathy in men). Additional research is required to gain a better understanding of the reasons behind gender disparities in eligibility and outcomes following HT. This would enable the fair allocation of resources and enhance patient care.


Assuntos
Disparidades em Assistência à Saúde , Insuficiência Cardíaca , Transplante de Coração , Humanos , Transplante de Coração/estatística & dados numéricos , Fatores Sexuais , Insuficiência Cardíaca/epidemiologia , Feminino , Masculino , Fatores de Risco , Prognóstico
11.
Cell Mol Life Sci ; 81(1): 246, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819479

RESUMO

The glycosylphosphatidylinositol (GPI) biosynthetic pathway in the endoplasmic reticulum (ER) is crucial for generating GPI-anchored proteins (GPI-APs), which are translocated to the cell surface and play a vital role in cell signaling and adhesion. This study focuses on two integral components of the GPI pathway, the PIGL and PIGF proteins, and their significance in trophoblast biology. We show that GPI pathway mutations impact on placental development impairing the differentiation of the syncytiotrophoblast (SynT), and especially the SynT-II layer, which is essential for the establishment of the definitive nutrient exchange area within the placental labyrinth. CRISPR/Cas9 knockout of Pigl and Pigf in mouse trophoblast stem cells (mTSCs) confirms the role of these GPI enzymes in syncytiotrophoblast differentiation. Mechanistically, impaired GPI-AP generation induces an excessive unfolded protein response (UPR) in the ER in mTSCs growing in stem cell conditions, akin to what is observed in human preeclampsia. Upon differentiation, the impairment of the GPI pathway hinders the induction of WNT signaling for early SynT-II development. Remarkably, the transcriptomic profile of Pigl- and Pigf-deficient cells separates human patient placental samples into preeclampsia and control groups, suggesting an involvement of Pigl and Pigf in establishing a preeclamptic gene signature. Our study unveils the pivotal role of GPI biosynthesis in early placentation and uncovers a new preeclampsia gene expression profile associated with mutations in the GPI biosynthesis pathway, providing novel molecular insights into placental development with implications for enhanced patient stratification and timely interventions.


Assuntos
Diferenciação Celular , Glicosilfosfatidilinositóis , Placentação , Trofoblastos , Trofoblastos/metabolismo , Trofoblastos/citologia , Feminino , Gravidez , Animais , Humanos , Camundongos , Placentação/genética , Glicosilfosfatidilinositóis/metabolismo , Glicosilfosfatidilinositóis/biossíntese , Placenta/metabolismo , Placenta/citologia , Via de Sinalização Wnt , Pré-Eclâmpsia/metabolismo , Pré-Eclâmpsia/genética , Pré-Eclâmpsia/patologia , Retículo Endoplasmático/metabolismo , Vias Biossintéticas/genética , Resposta a Proteínas não Dobradas , Sistemas CRISPR-Cas
12.
J Histochem Cytochem ; 72(5): 289-307, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38725414

RESUMO

Several types of cytotoxic insults disrupt endoplasmic reticulum (ER) homeostasis, cause ER stress, and activate the unfolded protein response (UPR). The role of ER stress and UPR activation in hypersensitivity pneumonitis (HP) has not been described. HP is an immune-mediated interstitial lung disease that develops following repeated inhalation of various antigens in susceptible and sensitized individuals. The aim of this study was to investigate the lung expression and localization of the key effectors of the UPR, BiP/GRP78, CHOP, and sXBP1 in HP patients compared with control subjects. Furthermore, we developed a mouse model of HP to determine whether ER stress and UPR pathway are induced during this pathogenesis. In human control lungs, we observed weak positive staining for BiP in some epithelial cells and macrophages, while sXBP1 and CHOP were negative. Conversely, strong BiP, sXBP1- and CHOP-positive alveolar and bronchial epithelial, and inflammatory cells were identified in HP lungs. We also found apoptosis and autophagy markers colocalization with UPR proteins in HP lungs. Similar results were obtained in lungs from an HP mouse model. Our findings suggest that the UPR pathway is associated with the pathogenesis of HP.


Assuntos
Alveolite Alérgica Extrínseca , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático , Células Epiteliais , Proteínas de Choque Térmico , Fator de Transcrição CHOP , Resposta a Proteínas não Dobradas , Proteína 1 de Ligação a X-Box , Animais , Alveolite Alérgica Extrínseca/patologia , Alveolite Alérgica Extrínseca/imunologia , Alveolite Alérgica Extrínseca/metabolismo , Humanos , Camundongos , Proteína 1 de Ligação a X-Box/metabolismo , Proteína 1 de Ligação a X-Box/genética , Proteínas de Choque Térmico/metabolismo , Fator de Transcrição CHOP/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Masculino , Pulmão/patologia , Pulmão/imunologia , Pulmão/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição de Fator Regulador X/metabolismo , Fatores de Transcrição/metabolismo , Modelos Animais de Doenças , Pessoa de Meia-Idade , Camundongos Endogâmicos C57BL , Adulto , Inflamação/patologia , Inflamação/metabolismo , Inflamação/imunologia
13.
Chemosphere ; 360: 142372, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38768783

RESUMO

The present study demonstrates, for the first time, the feasibility of a two-step process consisting of Electro-Fenton (EF) followed by microalgae to treat highly loaded real food processing wastewater along with resource recovery. In the first step, EF with a carbon felt cathode and Ti/RuO2-IrO2 anode was applied at different current densities (3.16 mA cm-2, 4.74 mA cm-2 and 6.32 mA cm-2) to decrease the amount of organic matter and turbidity and enhance biodegradability. In the second step, the EF effluents were submitted to microalgal treatment for 15 days using a mixed culture dominated by Scenedesmus sp., Chlorosarcinopsis sp., and Coelastrum sp. Results showed that current density impacted the amount of COD removed by EF, achieving the highest COD removal of 77.5% at 6.32 mA cm-2 with >95% and 74.3% of TSS and PO43- removal, respectively. With respect to microalgae, the highest COD removal of 85% was obtained by the culture in the EF effluent treated at 6.32 mA cm-2. Remarkably, not only 85% of the remaining organic matter was removed by microalgae, but also the totality of inorganic N and P compounds, as well as 65% of the Fe catalyst that was left after EF. The removal of inorganic species also demonstrates the high complementarity of both processes, since EF does not have the capacity to remove such compounds, while microalgae do not grow in the raw wastewater. Furthermore, a maximum of 0.8 g L-1 of biomass was produced after cultivation, with an accumulation of 32.2% of carbohydrates and 25.9% of lipids. The implementation of the two processes represents a promising sustainable approach for the management of industrial effluents, incorporating EF in a water and nutrient recycling system to produce biomass that could be valorized into clean fuels.


Assuntos
Biodegradação Ambiental , Microalgas , Eliminação de Resíduos Líquidos , Águas Residuárias , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Manipulação de Alimentos/métodos , Poluentes Químicos da Água/análise , Ferro/química , Peróxido de Hidrogênio/química , Análise da Demanda Biológica de Oxigênio , Scenedesmus/crescimento & desenvolvimento
14.
Biomed Phys Eng Express ; 10(4)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38670074

RESUMO

Background. New applications of 3D printing have recently appeared in the fields of radiotherapy and radiology, but the knowledge of many radiological characteristics of the compounds involved is still limited. Therefore, studies are needed to improve our understanding about the transport and interaction of ionizing radiation in these materials.Purpose. The purpose of this study is to perform an analysis of the most important radiation interaction parameters in thermoplastic materials used in Fused Deposition Modeling 3D printing. Additionally, we propose improvements to bring their characteristics closer to those of water and use them as water substitutes in applications such as radiodiagnosis, external radiotherapy, and brachytherapy.Methods. We have calculated different magnitudes as mass linear attenuation, mass energy absorption coefficients, as well as stopping power and electronic density of several thermoplastic materials along with various compounds that have been used as water substitutes and in a new proposed blend. To perform these computations, we have used the XCOM and ESTAR databases from NIST and the EGSnrc code for Montecarlo simulations.Results. From the representation of the calculated interaction parameters, we have been able to establish relationships between their properties and the proportion of certain chemical elements. In addition, studying these same characteristics in different commercial solutions used as substitutes for water phantoms allows us to extrapolate improvements for these polymers.Conclusion. The radiological characteristics of the analyzed thermoplastic materials can be improved by adding some chemical elements with atomic numbers higher than oxygen and by using polyethylene in new blends.


Assuntos
Polímeros , Impressão Tridimensional , Água , Água/química , Polímeros/química , Método de Monte Carlo , Imagens de Fantasmas , Plásticos/química , Simulação por Computador , Humanos , Braquiterapia/métodos
15.
Antonie Van Leeuwenhoek ; 117(1): 47, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427176

RESUMO

Desulfofundulus kuznetsovii is a thermophilic, spore-forming sulphate-reducing bacterium in the family Peptococcaceae. In this study, we describe a newly isolated strain of D. kuznetsovii, strain TPOSR, and compare its metabolism to the type strain D. kuznetsovii 17T. Both strains grow on a large variety of alcohols, such as methanol, ethanol and propane-diols, coupled to the reduction of sulphate. Strain 17T metabolizes methanol via two routes, one involving a cobalt-dependent methyl transferase and the other using a cobalt-independent alcohol dehydrogenase. However, strain TPOSR, which shares 97% average nucleotide identity with D. kuznetsovii strain 17T, lacks several genes from the methyl transferase operon found in strain 17T. The gene encoding the catalytically active methyl transferase subunit B is missing, indicating that strain TPOSR utilizes the alcohol dehydrogenase pathway exclusively. Both strains grew with methanol during cobalt starvation, but growth was impaired. Strain 17T was more sensitive to cobalt deficiency, due to the repression of its methyl transferase system. Our findings shed light on the metabolic diversity of D. kuznetsovii and their metabolic differences of encoding one or two routes for the conversion of methanol.


Assuntos
Álcool Desidrogenase , Metanol , Peptococcaceae , Álcool Desidrogenase/genética , Álcool Desidrogenase/metabolismo , Metanol/metabolismo , Oxirredução , Transferases/metabolismo , Sulfatos/metabolismo , Cobalto , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo
16.
J Psychiatry Neurosci ; 49(2): E96-E108, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38490646

RESUMO

BACKGROUND: The assessment of deep brain stimulation (DBS) as a therapeutic alternative for treating Alzheimer disease (AD) is ongoing. We aimed to determine the effects of intracranial self-stimulation at the medial forebrain bundle (MFB-ICSS) on spatial memory, neurodegeneration, and serum expression of microRNAs (miRNAs) in a rat model of sporadic AD created by injection of streptozotocin. We hypothesized that MFB-ICSS would reverse the behavioural effects of streptozotocin and modulate hippocampal neuronal density and serum levels of the miRNAs. METHODS: We performed Morris water maze and light-dark transition tests. Levels of various proteins, specifically amyloid-ß precurser protein (APP), phosphorylated tau protein (pTAU), and sirtuin 1 (SIRT1), and neurodegeneration were analyzed by Western blot and Nissl staining, respectively. Serum miRNA expression was measured by reverse transcription polymerase chain reaction. RESULTS: Male rats that received streptozotocin had increased hippocampal levels of pTAU S202/T205, APP, and SIRT1 proteins; increased neurodegeneration in the CA1, dentate gyrus (DG), and dorsal tenia tecta; and worse performance in the Morris water maze task. No differences were observed in miRNAs, except for miR-181c and miR-let-7b. After MFB-ICSS, neuronal density in the CA1 and DG regions and levels of miR-181c in streptozotocin-treated and control rats were similar. Rats that received streptozotocin and underwent MFB-ICSS also showed lower levels of miR-let-7b and better spatial learning than rats that received streptozotocin without MFB-ICSS. LIMITATIONS: The reversal by MFB-ICSS of deficits induced by streptozotocin was fairly modest. CONCLUSION: Spatial memory performance, hippocampal neurodegeneration, and serum levels of miR-let-7b and miR-181c were affected by MFB-ICSS under AD-like conditions. Our results validate the MFB as a potential target for DBS and lend support to the use of specific miRNAs as promising biomarkers of the effectiveness of DBS in combatting AD-associated cognitive deficits.


Assuntos
Doença de Alzheimer , MicroRNAs , Ratos , Masculino , Animais , Ratos Wistar , Autoestimulação/fisiologia , Estreptozocina/toxicidade , Aprendizagem Espacial , Doença de Alzheimer/terapia , Sirtuína 1/farmacologia , Hipocampo , MicroRNAs/genética , Aprendizagem em Labirinto
17.
mSystems ; 9(3): e0096723, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38323850

RESUMO

The biological route of nitrate reduction has important implications for the bioavailability of nitrogen within ecosystems. Nitrate reduction via nitrite, either to ammonium (ammonification) or to nitrous oxide or dinitrogen (denitrification), determines whether nitrogen is retained within the system or lost as a gas. The acidophilic sulfate-reducing bacterium (aSRB) Acididesulfobacillus acetoxydans can perform dissimilatory nitrate reduction to ammonium (DNRA). While encoding a Nar-type nitrate reductase, A. acetoxydans lacks recognized nitrite reductase genes. In this study, A. acetoxydans was cultivated under conditions conducive to DNRA. During cultivations, we monitored the production of potential nitrogen intermediates (nitrate, nitrite, nitric oxide, hydroxylamine, and ammonium). Resting cell experiments were performed with nitrate, nitrite, and hydroxylamine to confirm their reduction to ammonium, and formed intermediates were tracked. To identify the enzymes involved in DNRA, comparative transcriptomics and proteomics were performed with A. acetoxydans growing under nitrate- and sulfate-reducing conditions. Nitrite is likely reduced to ammonia by the previously undescribed nitrite reductase activity of the NADH-linked sulfite reductase AsrABC, or by a putatively ferredoxin-dependent homolog of the nitrite reductase NirA (DEACI_1836), or both. We identified enzymes and intermediates not previously associated with DNRA and nitrosative stress in aSRB. This increases our knowledge about the metabolism of this type of bacteria and helps the interpretation of (meta)genome data from various ecosystems on their DNRA potential and the nitrogen cycle.IMPORTANCENitrogen is crucial to any ecosystem, and its bioavailability depends on microbial nitrogen-transforming reactions. Over the recent years, various new nitrogen-transforming reactions and pathways have been identified, expanding our view on the nitrogen cycle and metabolic versatility. In this study, we elucidate a novel mechanism employed by Acididesulfobacillus acetoxydans, an acidophilic sulfate-reducing bacterium, to reduce nitrate to ammonium. This finding underscores the diverse physiological nature of dissimilatory reduction to ammonium (DNRA). A. acetoxydans was isolated from acid mine drainage, an extremely acidic environment where nitrogen metabolism is poorly studied. Our findings will contribute to understanding DNRA potential and variations in extremely acidic environments.


Assuntos
Compostos de Amônio , Nitratos , Nitratos/metabolismo , Compostos de Amônio/metabolismo , Nitritos/metabolismo , Ecossistema , Desnitrificação , Bactérias/metabolismo , Hidroxilamina , Nitrito Redutases/metabolismo , Nitrogênio , Hidroxilaminas , Sulfatos
18.
Environ Microbiol ; 26(2): e16565, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38356112

RESUMO

Acid mine drainage (AMD) waters are a severe environmental threat, due to their high metal content and low pH (pH <3). Current technologies treating AMD utilize neutrophilic sulfate-reducing microorganisms (SRMs), but acidophilic SRM could offer advantages. As AMDs are low in organics these processes require electron donor addition, which is often incompletely oxidized into organic acids (e.g., acetic acid). At low pH, acetic acid is undissociated and toxic to microorganisms. We investigated the stress response of the acetotrophic Acididesulfobacillus acetoxydans to acetic acid. A. acetoxydans was cultivated in bioreactors at pH 5.0 (optimum). For stress experiments, triplicate reactors were spiked until 7.5 mM of acetic acid and compared with (non-spiked) triplicate reactors for physiological, transcriptomic, and membrane lipid changes. After acetic acid spiking, the optical density initially dropped, followed by an adaptation phase during which growth resumed at a lower growth rate. Transcriptome analysis revealed a downregulation of genes involved in glutamate and aspartate synthesis following spiking. Membrane lipid analysis revealed a decrease in iso and anteiso fatty acid relative abundance; and an increase of acetyl-CoA as a fatty acid precursor. These adaptations allow A. acetoxydans to detoxify acetic acid, creating milder conditions for other microorganisms in AMD environments.


Assuntos
Ácido Acético , Sulfatos , Reatores Biológicos , Ácidos , Ácidos Graxos , Lipídeos de Membrana
19.
Data Brief ; 53: 110142, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38357451

RESUMO

The present database contains brain activity of subjective tinnitus sufferers at identifying their sound tinnitus. The main objective of this database is to provide spontaneous Electroencephalographic (EEG) activity at rest, and evoked EEG activity when tinnitus sufferers attempt to identify their sound tinnitus among 54 tinnitus sound examples. For the database, 37 volunteers were recruited: 15 ones without tinnitus (Control Group - CG), and 22 ones with tinnitus (Tinnitus Group - TG). For EEG recording, 30 channels were used to record two conditions: 1) basal condition, where the volunteer remained in a state of rest with the open eyes for two minutes; and 2) active condition, where the volunteer must have identified his/her sound stimulus by pressing a key. For the active condition, a sound-tinnitus library was generated in accordance with the most typical acoustic properties of tinnitus. The library consisted in ten pure tones (250 Hz, 500 Hz, 1 kHz, 2 kHz, 3 kHz, 3.5 kHz, 4 kHz, 6 kHz, 8 kHz, 10 kHz), a White Noise (WN), a Narrow Band noise-High frequencies (NBH, 4 kHz-10 kHz), a Narrow Band noise-Medium frequencies (NBM,1 kHz-4 kHz), a Narrow-Band noise Low frequencies (NBL, 250 Hz-1 kHz), ten pure tones combined with WN, ten pure tones superimposed with NBH, ten tones with NBM and ten pure tones combined with NBL. In total, 54 sound-tinnitus were applied for both groups. In the case of CG, volunteers must have identified a sound at 3.5 kHz. In addition to EEG information, a csv-file with audiometric and psychoacoustic information of volunteers is provided. For TG, this information refers to: 1) hearing level, 2) type of tinnitus, 3) tinnitus frequency, 4) tinnitus perception, 5) Hospital Anxiety and Depression Scale (HADS) and 6) Tinnitus Functional Index (TFI). For CG, the information refers to: 1) hearing level, and 2) HADS.

20.
Pediatr Neurol ; 152: 34-40, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38184986

RESUMO

BACKGROUND: Duchenne muscular dystrophy (DMD) is a genetic condition that causes muscle weakness and begins in early childhood. To treat its complications, the rehabilitation program includes physical therapy, mainly on the musculoskeletal and the respiratory complications that appear on the evolution of the disease. This study aims to explore the effects of physical therapy with or without an at-home program on motor function among children with DMD. METHODS: A randomized controlled trial was carried out for one year (one group with at-home and conventional physical therapy and another with conventional physical therapy). Motor function was measured using the Motor Function Measure (MFM) scale, the Vignos and Brooke scales, the Timed-up-and-Go test, and the six-minute walk distance test. RESULTS: Twenty-seven participants with DMD participated in this study. In the at-home and conventional physical therapy group, better motor function at the distal and global level was maintained, per the results of the MFM scale (P < 0.05). The rest of the variables did not achieve statistically significant changes. CONCLUSIONS: Our results suggest that complementing conventional treatment with at-home treatment in which the family is involved maintains better motor function, in participants with DMD.


Assuntos
Distrofia Muscular de Duchenne , Criança , Humanos , Pré-Escolar , Distrofia Muscular de Duchenne/terapia , Equilíbrio Postural , Estudos de Tempo e Movimento , Caminhada/fisiologia , Modalidades de Fisioterapia
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