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1.
ChemSusChem ; : e202401659, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237459

RESUMO

Sustainable hydrogen production is focused on anion exchange membrane (AEM) water electrolyzers (AEMWEs), which still require more development to achieve high performance and durability. Here, we propose a novel class of porous organic polymers (POPs) as durable solid-ionomers for AEMWEs, which was prepared by reacting the 4-methylpiperidone with trifunctional or a mixture of trifunctional:difunctional aromatic monomers (in a 2:3 mol ratio). The resulting POP ionomers exhibited exceptional electrochemical properties and remarkable alkaline stability. Particularly noteworthy are the corresponding AEMWEs, which showed an outstanding current density of 13.4 A cm-2 at 2.0 V under 80°C in 1 M KOH solution, which is the highest performance reported in the particulate-ionomers AEMWE state of the art. Moreover, they demonstrated durability at a current density of 0.5 A cm-2 for over 500 hours with a voltage decay rate of 120 µV h-1. This work offers valuable perspectives on the designing of robust and high-performance solid-state ionomers through low-cost electrophilic aromatic substitution reactions for high-performance energy conversion devices.

2.
Macromolecules ; 57(16): 8187-8201, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39219805

RESUMO

A series of polyimides (PIs) was synthesized from 6FDA and two o-OH substituted diamines having bulky pendant phenyl, Ph, and trifluoromethyl, CF3, groups as precursors for thermally rearranged polybenzoxazole, TR-PBO, membranes. One diamine had two pendant Ph substituents; in the other, the substituents were Ph and CF3. Applying azeotropic and chemical cyclizations allowed the obtention of four o-hydroxy (o-OH) or/and o-acetoxy (o-OAc) substituted PIs depending on the imidization method. The PIs were labeled as 3Ph-OH, 4Ph-OH, or 3Ph-OAc and 4PH-OAc, respectively. Thermal rearrangements of all four precursors were investigated in the interval from 350 to 450 °C. The conversions to TR-PBO increased with temperature, and almost quantitative conversions were obtained at temperatures close to 450 °C, although o-OH substituted PIs reached conversions slightly higher than those of o-OAc PIs at a given temperature. The TR-polymers' fractional free volume (FFV) also increased with conversion but was higher for the o-OAc substituted precursors. Despite the high TR-PBO conversions, self-supported uniform TR membranes with reasonable mechanical properties were obtained, except for 4Ph-OH. Gas separation behavior of the membranes significantly improved after the thermal treatment, and the final CO2/CH4 permselectivities lay between the 1991 and 2008 Robeson upper bounds. Particularly, TR-membranes derived from o-OAc precursors and with pendant CF3 group demonstrated better gas transport properties with values of P (CO2) = 1121 barrer and αCO2/CH4 = 29 for 3Ph-OAc derived membrane, which positioned it beyond the 2008 upper limit.

3.
Artigo em Inglês | MEDLINE | ID: mdl-39320115

RESUMO

Microporous glassy polymer membranes suffer from physical aging, which adversely affects their performance in the short time frame. We show that the aging propensity of a model microporous polymer, poly(1-trimethylsilyl-1-propyne) (PTMSP), can be effectively mitigated by blending with as little as 5 wt % porous polymer network (PPN) composed of triptycene and isatin. The aging behavior of these materials was monitored via N2 pure gas permeability measurements over the course of 3 weeks, showing a 14% decline in PTMSP blended with 5 wt % PPN vs a 41% decline in neat PTMSP. Noteworthy, PPNs are 2 orders of magnitude cheaper than the porous aromatic frameworks previously used to control PTMSP aging. A variety of experimental and computational techniques, such as Positron Annihilation Lifetime Spectroscopy (PALS), free volume measurements, cross-polarization/magic angle spinning (CP/MAS) 13C NMR, transport measurements and molecular dynamics (MD) simulations were used to uncover the molecular mechanisms leading to enhanced aging resistance. We show that partial PTMSP chain adsorption into the PPN porosity reduces the PTMSP local segmental mobility, leading to improved aging resistance. Permeability coefficients were broken into their elementary sorption and diffusion contributions, to elucidate the mechanism by which the reduced PTMSP local segmental mobility affects selectivity in gas separation applications. Finally, we demonstrate that in these systems, where both chemical and physical interactions take place, transport coefficients must be corrected for thermodynamic nonidealities to avoid erroneous interpretation of the results.

4.
Nat Immunol ; 25(9): 1593-1606, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39112630

RESUMO

The thymus is essential for establishing adaptive immunity yet undergoes age-related involution that leads to compromised immune responsiveness. The thymus is also extremely sensitive to acute insult and although capable of regeneration, this capacity declines with age for unknown reasons. We applied single-cell and spatial transcriptomics, lineage-tracing and advanced imaging to define age-related changes in nonhematopoietic stromal cells and discovered the emergence of two atypical thymic epithelial cell (TEC) states. These age-associated TECs (aaTECs) formed high-density peri-medullary epithelial clusters that were devoid of thymocytes; an accretion of nonproductive thymic tissue that worsened with age, exhibited features of epithelial-to-mesenchymal transition and was associated with downregulation of FOXN1. Interaction analysis revealed that the emergence of aaTECs drew tonic signals from other functional TEC populations at baseline acting as a sink for TEC growth factors. Following acute injury, aaTECs expanded substantially, further perturbing trophic regeneration pathways and correlating with defective repair of the involuted thymus. These findings therefore define a unique feature of thymic involution linked to immune aging and could have implications for developing immune-boosting therapies in older individuals.


Assuntos
Envelhecimento , Células Epiteliais , Fatores de Transcrição Forkhead , Regeneração , Timo , Timo/imunologia , Animais , Células Epiteliais/imunologia , Regeneração/imunologia , Camundongos , Envelhecimento/imunologia , Fatores de Transcrição Forkhead/metabolismo , Fatores de Transcrição Forkhead/genética , Transição Epitelial-Mesenquimal/imunologia , Camundongos Endogâmicos C57BL , Masculino , Timócitos/imunologia , Timócitos/metabolismo , Feminino , Análise de Célula Única
5.
PLoS One ; 19(7): e0307307, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39024223

RESUMO

Tuberculosis (TB) is an infectious, chronic, and progressive disease occurring globally. Human TB is caused mainly by Mycobacterium tuberculosis (M. tuberculosis), while the main causative agent of bovine TB is Mycobacterium bovis (M. bovis). The latter is one of the most important cattle pathogens and is considered the main cause of zoonotic TB worldwide. The mechanisms responsible for tissue damage (necrosis) during post-primary TB remain elusive. Recently, IL-17A was reported to be important for protection against M. tuberculosis infection, but it is also related to the production of an intense inflammatory response associated with necrosis. We used two M. bovis isolates with different levels of virulence and high IL-17A production to study this important cytokine's contrasting functions in a BALB/c mouse model of pulmonary TB. In the first part of the study, the gene expression kinetics and cellular sources of IL-17A were determined by real time PCR and immunohistochemistry respectively. Non-infected lungs showed low production of IL-17A, particularly by the bronchial epithelium, while lungs infected with the low-virulence 534 strain showed high IL-17A expression on Day 3 post-infection, followed by a decrease in expression in the early stage of the infection and another increase during late infection, on Day 60, when very low bacillary burdens were found. In contrast, infection with the highly virulent strain 04-303 induced a peak of IL-17A expression on Day 14 of infection, 1 week before extensive pulmonary necrosis was seen, being lymphocytes and macrophages the most important sources. In the second part of the study, the contribution of IL-17A to immune protection and pulmonary necrosis was evaluated by suppressing IL-17A via the administration of specific blocking antibodies. Infection with M. bovis strain 534 and treatment with IL-17A neutralizing antibodies did not affect mouse survival but produced a significant increase in bacillary load and a non-significant decrease in inflammatory infiltrate and granuloma area. In contrast, mice infected with the highly virulent 04-303 strain and treated with IL-17A blocking antibodies showed a significant decrease in survival, an increase in bacillary loads on Day 24 post-infection, and significantly more and earlier necrosis. Our results suggest that high expression of IL-17A is more related to protection than necrosis in a mouse model of pulmonary TB induced by M. bovis strains.


Assuntos
Interleucina-17 , Camundongos Endogâmicos BALB C , Mycobacterium bovis , Tuberculose Pulmonar , Interleucina-17/metabolismo , Interleucina-17/imunologia , Animais , Mycobacterium bovis/patogenicidade , Mycobacterium bovis/imunologia , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/microbiologia , Tuberculose Pulmonar/patologia , Camundongos , Virulência , Pulmão/microbiologia , Pulmão/patologia , Pulmão/imunologia , Feminino , Bovinos
6.
Calcif Tissue Int ; 115(4): 382-392, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39066926

RESUMO

To explore how sex hormone fluctuations may affect bone metabolism, this study aimed to examine P1NP and ß-CTX-1 concentrations across the menstrual and oral contraceptive (OC) cycle phases in response to running. 17ß-oestradiol, progesterone, P1NP and ß-CTX-1 were analysed pre- and post-exercise in eight eumenorrheic females in the early-follicular, late-follicular, and mid-luteal phases, while 8 OC users were evaluated during the withdrawal and active pill-taking phases. The running protocol consisted of 8 × 3min treadmill runs at 85% of maximal aerobic speed. 17ß-oestradiol concentrations (pg·ml-1) were lower in early-follicular (47.22 ± 39.75) compared to late-follicular (304.95 ± 235.85;p = < 0.001) and mid-luteal phase (165.56 ± 80.6;p = 0.003) and higher in withdrawal (46.51 ± 44.09) compared to active pill-taking phase (10.88 ± 11.24;p < 0.001). Progesterone (ng·ml-1) was higher in mid-luteal (13.214 ± 4.926) compared to early-follicular (0.521 ± 0.365; p < 0.001) and late-follicular phase (1.677 ± 2.586;p < 0.001). In eumenorrheic females, P1NP concentrations (ng·ml-1) were higher in late-follicular (69.97 ± 17.84) compared to early-follicular (60.96 ± 16.64;p = 0.006;) and mid-luteal phase (59.122 ± 11.77;p = 0.002). ß-CTX-1 concentrations (ng·ml-1) were lower in mid-luteal (0.376 ± 0.098) compared to late-follicular (0.496 ± 0.166; p = 0.001) and early-follicular phase (0.452 ± 0.148; p = 0.039). OC users showed higher post-exercise P1NP concentrations in withdrawal phase (61.75 ± 8.32) compared to post-exercise in active pill-taking phase (45.45 ± 6;p < 0.001). Comparing hormonal profiles, post-exercise P1NP concentrations were higher in early-follicular (66.91 ± 16.26;p < 0.001), late-follicular (80.66 ± 16.35;p < 0.001) and mid-luteal phases (64.57 ± 9.68;p = 0.002) to active pill-taking phase. These findings underscore the importance of studying exercising females with different ovarian hormone profiles, as changes in sex hormone concentrations affect bone metabolism in response to running, showing a higher post-exercise P1NP concentrations in all menstrual cycle phases compared with active pill-taking phase of the OC cycle.


Assuntos
Biomarcadores , Anticoncepcionais Orais , Ciclo Menstrual , Corrida , Humanos , Feminino , Ciclo Menstrual/fisiologia , Corrida/fisiologia , Adulto , Anticoncepcionais Orais/administração & dosagem , Adulto Jovem , Biomarcadores/sangue , Biomarcadores/análise , Progesterona/sangue , Estradiol/sangue , Remodelação Óssea/fisiologia , Remodelação Óssea/efeitos dos fármacos , Osso e Ossos/metabolismo , Osso e Ossos/efeitos dos fármacos
7.
Int J Pediatr Otorhinolaryngol ; 182: 112011, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38865866

RESUMO

OBJECTIVE: To determine whether implementation of an education-based intervention can sustainably improve upstream and downstream outcomes in intubated patients in a pediatric intensive care unit (PICU) in a low-resource country. DESIGN: Quality improvement study comparing airway-related morbidity in two previously studied patient cohorts pre-intervention (Epoch 1) and immediately post-intervention (Epoch 2) with a third cohort thirty-six months post-intervention (Epoch 3). SETTING: PICU of the largest public children's hospital in El Salvador. PATIENTS: 147 patients under 18 years requiring intubation and mechanical ventilation (MV) met inclusion criteria in the long-term follow-up period and were consecutively sampled without exclusion (Epoch 3) (compared to 98 previously studied patients in the short-term follow-up period (Epoch 2)). INTERVENTION: A low-cost, education-based intervention to close knowledge gaps, improve communication among PICU doctors, nurses, and respiratory therapists, and optimize patient outcomes. MEASUREMENTS AND MAIN RESULTS: The primary outcome measure was change in unplanned extubation (UE) between Epochs 2 and 3. Other outcomes included use of cuffed endotracheal tubes (ETT), rate of elective ETT change and days of MV. The 17 % decrease in UE previously reported for Epoch 2 was sustained in Epoch 3. There was a statistically significant increase in use of cuffed ETT from 35.7 % in Epoch 2-55.1 % in Epoch 3 (p = 0.003, z-score -2.99). There was also a statistically significant mean difference in rate of elective ETT change per 100 MV days from Epoch 2 to Epoch 3 of 1.7 (p = 0.007; 95 % CI 0.15-0.84). There was no change in MV days from Epoch 2 to Epoch 3 (p-value 0.764; 95 % CI -1.48-2.02). Beyond these quantifiable results, many unanticipated practice changes were observed three years after the initial intervention. CONCLUSIONS: Sustained improvement in upstream and downstream outcomes (UE, cuffed ETT use, elective ETT change) for intubated patients in a low-resource PICU were observed three years after a low-cost, low-touch, education-based intervention.


Assuntos
Unidades de Terapia Intensiva Pediátrica , Intubação Intratraqueal , Melhoria de Qualidade , Respiração Artificial , Humanos , Masculino , Feminino , Pré-Escolar , Criança , Lactente , Extubação , Adolescente , Seguimentos
8.
Front Public Health ; 12: 1411681, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38932785

RESUMO

Background: This work describes a sustainable and replicable initiative to optimize multi-disciplinary care and uptake of clinical best practices for patients in a pediatric intensive care unit in Low/Middle Income Countries and to understand the various factors that may play a role in the reduction in child mortality seen after implementation of the Quality Improvement Initiative. Methods: This was a longitudinal assessment of a quality improvement program with the primary outcome of intubated pediatric patient mortality. The program was assessed 36 months following implementation of the quality improvement intervention using a t-test with linear regression to control for co-variates. An Impact Pathway model was developed to describe potential pathways for improvement, and context was added with an exploratory analysis of adoption of the intervention and locally initiated interventions. Results: 147 patients were included in the sustainability cohort. Comparing the initial post-implementation cohort to the sustainability cohort, the overall PICU unexpected extubations per 100 days mechanical ventilation decreased significantly from baseline (6.98) to the first year post intervention (3.52; p < 0.008) but plateaued without further significant decrease in the final cohort (3.0; p = 0.73), whereas the mortality decreased from 22.4 (std 0.42) to 9.5% (std 0.29): p value: 0.002 (confidence intervals: 0.05;0.21). The regression model that examined age, sex, diagnosis and severity of illness (via aggregate Pediatric Risk of Mortality (PRISM) scores between epochs) yielded an adjusted R-squared (adjusting for the number of predictors) value of 0.046, indicating that approximately 4.6% of the variance in mortality was explained by the predictors included in the model. The overall significance of the regression model was supported by an F-statistic of 3.198 (p = 0.00828). age, weight, diagnosis, and severity of illness. 15 new and locally driven quality practices were observed in the PICU compared to the initial post-implementation time period. The Impact Pathway model suggested multiple unique potential pathways connecting the improved patient outcomes with the intervention components. Conclusion: Sustained improvements were seen in the care of intubated pediatric patients. While some of this improvement may be attributable to the intervention, it appears likely that the change is multifactorial, as evidenced by a significant number of new quality improvement projects initiated by the local clinical team. Although currently limited by available data, the use of Driver Diagram and Impact Pathway models demonstrates several proposed causal pathways and holds potential for further elucidating the complex dynamics underlying such improvements.


Assuntos
Unidades de Terapia Intensiva Pediátrica , Melhoria de Qualidade , Humanos , Masculino , Feminino , Pré-Escolar , Lactente , Criança , Estudos Longitudinais , Países em Desenvolvimento , Mortalidade da Criança , Respiração Artificial/estatística & dados numéricos
9.
PLoS Negl Trop Dis ; 18(6): e0012256, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38870209

RESUMO

The Aedes aegypti cadherin-like protein (Aae-Cad) and the membrane-bound alkaline phosphatase (Aae-mALP) are membrane proteins identified as putative receptors for the larvicidal Cry toxins produced by Bacillus thuringiensis subsp. israelensis bacteria. Cry toxins are the most used toxins in the control of different agricultural pest and mosquitos. Despite the relevance of Aae-Cad and Aae-mALP as possible toxin-receptors in mosquitoes, previous efforts to establish a clear functional connection among them and Cry toxins activity have been relatively limited. In this study, we used CRISPR-Cas9 to generate knockout (KO) mutations of Aae-Cad and Aae-mALP. The Aae-mALP KO was successfully generated, in contrast to the Aae-Cad KO which was obtained only in females. The female-linked genotype was due to the proximity of aae-cad gene to the sex-determining loci (M:m). Both A. aegypti KO mutant populations were viable and their insect-development was not affected, although a tendency on lower egg hatching rate was observed. Bioassays were performed to assess the effects of these KO mutations on the susceptibility of A. aegypti to Cry toxins, showing that the Aae-Cad female KO or Aae-mALP KO mutations did not significantly alter the susceptibility of A. aegypti larvae to the mosquitocidal Cry toxins, including Cry11Aa, Cry11Ba, Cry4Ba, and Cry4Aa. These findings suggest that besides the potential participation of Aae-Cad and Aae-mALP as Cry toxin receptors in A. aegypti, additional midgut membrane proteins are involved in the mode of action of these insecticidal toxins.


Assuntos
Aedes , Fosfatase Alcalina , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias , Sistemas CRISPR-Cas , Caderinas , Endotoxinas , Proteínas Hemolisinas , Animais , Aedes/genética , Aedes/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Fosfatase Alcalina/genética , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Endotoxinas/genética , Endotoxinas/metabolismo , Feminino , Caderinas/genética , Caderinas/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Resistência a Inseticidas/genética , Técnicas de Inativação de Genes , Larva/genética , Larva/crescimento & desenvolvimento , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Masculino , Inseticidas/farmacologia
10.
Sci Rep ; 14(1): 14668, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918484

RESUMO

A growing dependence on real-time positioning apps for navigation, safety, and location-based services necessitates a deep understanding of latency challenges within cloud-based Global Navigation Satellite System (GNSS) solutions. This study analyses a GNSS real-time positioning app on smartphones that utilizes cloud computing for positioning data delivery. The study investigates and quantifies diverse latency contributors throughout the system architecture, including GNSS signal acquisition, data transmission, cloud processing, and result dissemination. Controlled experiments and real-world scenarios are employed to assess the influence of network conditions, device capabilities, and cloud server load on overall positioning latency. Findings highlight system bottlenecks and their relative contributions to latency. Additionally, practical recommendations are presented for developers and cloud service providers to mitigate these challenges and guarantee an optimal user experience for real-time positioning applications. This study not only elucidates the complex interplay of factors affecting GNSS app latency, but also paves the way for future advancements in cloud-based positioning solutions, ensuring the accuracy and timeliness critical for safety-critical and emerging applications.

11.
Int J Biol Macromol ; 270(Pt 2): 132393, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38761898

RESUMO

Light chain amyloidosis is a conformational disease caused by the abnormal proliferation and deposition of antibody light chains as amyloid fibers in organs and tissues. The effect of Cu(II) binding to the model recombinant protein 6aJL2-R24G was previously characterized in our group, and we found an acceleration of the aggregation kinetics of the protein. In this study, in order to confirm the Cu(II) binding sites, histidine variants of 6aJL2-R24G were prepared and the effects of their interaction with Cu(II) were analyzed by circular dichroism, fluorescence spectroscopy, isothermal calorimetry titrations, and molecular dynamics simulations. Confirming our earlier work, we found that His8 and His99 are the highest affinity Cu(II) binding sites, and that Cu(II) binding to both sites is a cooperative event.


Assuntos
Cobre , Histidina , Ligação Proteica , Cobre/metabolismo , Cobre/química , Histidina/química , Histidina/metabolismo , Humanos , Sítios de Ligação , Simulação de Dinâmica Molecular , Cadeias Leves de Imunoglobulina/metabolismo , Cadeias Leves de Imunoglobulina/genética , Cadeias Leves de Imunoglobulina/química , Amiloidose de Cadeia Leve de Imunoglobulina/metabolismo , Amiloidose de Cadeia Leve de Imunoglobulina/genética , Amiloidose/metabolismo , Amiloidose/genética , Cinética
12.
Heliyon ; 10(9): e30212, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38694129

RESUMO

Chondrosarcoma (CS) is a malignant bone tumor arising from cartilage-producing cells. The conventional subtype of CS typically develops within a dense cartilaginous matrix, creating an environment deficient in oxygen and nutrients, necessitating metabolic adaptation to ensure proliferation under stress conditions. Although ketone bodies (KBs) are oxidized by extrahepatic tissue cells such as the heart and brain, specific cancer cells, including CS cells, can undergo ketolysis. In this study, we found that KBs catabolism is activated in CS cells under nutrition-deprivation conditions. Interestingly, cytosolic ß-hydroxybutyrate dehydrogenase 2 (BDH2), rather than mitochondrial BDH1, is expressed in these cells, indicating a specific metabolic adaptation for ketolysis in this bone tumor. The addition of the KB, ß-Hydroxybutyrate (ß-HB) in serum-starved CS cells re-induced the expression of BDH2, along with the key ketolytic enzyme 3-oxoacid CoA-transferase 1 (OXCT1) and monocarboxylate transporter-1 (MCT1). Additionally, internal ß-HB production was quantified in supplied and starved cells, suggesting that CS cells are also capable of ketogenesis alongside ketolysis. These findings unveil a novel metabolic adaptation wherein nutrition-deprived CS cells utilize KBs for energy supply and proliferation.

13.
Polymers (Basel) ; 16(10)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38794590

RESUMO

A good integration of the polymer materials that form a mixed-matrix membrane (MMM) for gas separation is essential to reaching interesting permselective properties. In this work, a porous polymer network (PPN), obtained by combining triptycene and trifluoroacetophenone, has been used as a filler, which was blended with two o-hydroxypolyamides (HPAs) that act as polymer matrices. These polymer matrices have been thermally treated to induce a thermal rearrangement (TR) of the HPAs to polybenzoxazoles (ß-TR-PBOs) through a solid-state reaction. For its structural study, various techniques have been proposed that allow us to undertake a morphological investigation into the integration of these materials. To access the internal structure of the MMMs, three different methods were used: a polishing process for the material surface, the partial dissolution of the polymer matrix, or argon plasma etching. The argon plasma technique has not only revealed its potential to visualize the internal structure of these materials; it has also been proven to allow for the transformation of their permselective properties. Force modulation and phase contrast in lift-mode techniques, along with the topographic images obtained via the tapping mode using a scanning probe microscope (SPM), have allowed us to study the distribution of the filler particles and the interaction of the polymer and the filler. The morphological information obtained via SPM, along with that of other more commonly used techniques (SEM, TGA, DSC, FTIR, WASX, gas adsorption, and permeability measurements), has allowed us to postulate the most probable structural configuration in this type of system.

14.
Gac Med Mex ; 160(1): 32-38, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38753549

RESUMO

BACKGROUND: Suicidal behavior in adolescents is a growing public health problem. Knowing its risk factors is key for reducing it. OBJECTIVE: To identify the relationship between two suicidal behaviors (ideation and attempt) and eight mental health problems (MHPs) in Mexican adolescents. MATERIAL AND METHODS: Through an online survey of adolescent students from 20 states, the following information was screened: symptomatology of six MHPs (affective problems/depression, behavioral problems, somatic problems, inattention and hyperactivity problems, oppositional defiant problems and anxiety problems) and suicidal behavior (suicidal ideation and suicide attempts). MHP and suicidal behavior frequencies and percentages were analyzed, and associations were sought using binary logistic regression. RESULTS: Six-thousand seven hundred sixty-six adolescents completed the survey, out of whom 61.02% were females, with ages ranging between 11 and 19 years (16.38 ± 1.33); 10% reported suicidal behavior, and between 3 and 5%, MHPs. The predictors (χ2(8) = 387.13, p < 0.001) of suicidal behavior were affective problems/depression, behavioral problems, somatic problems, oppositional defiant problems and anxiety problems. CONCLUSION: Five mental health problems increased the risk of reporting suicidal behaviors.


ANTECEDENTES: Las conductas suicidas en adolescentes son un problema de salud pública que va en aumento. Conocer sus factores de riesgo es clave para reducirlas. OBJETIVO: Identificar la relación entre dos conductas suicidas (ideación e intento) y ocho problemas de salud mental (PSM) en adolescentes mexicanos. MATERIAL Y MÉTODOS: Mediante una encuesta en línea a adolescentes escolarizados de 20 estados, se tamizó la siguiente información: sintomatología de seis PSM (problemas afectivos/depresión, problemas conductuales, problemas somáticos, problemas de inatención e hiperactividad, problemas oposicionistas desafianes y problemas de ansiedad) y conducta suicida (ideación e intentos de suicidio). Se analizaron frecuencias y porcentajes y se indagó asociación mediante regresión logística binaria. RESULTADOS: Completaron la encuesta 6766 adolescentes entre 11 y 19 años (16.38 ± 1.33), 61.02 % del sexo femenino. El 10 % reportó conducta suicida y entre 3 y 5 %, PSM. Los factores predictivos (χ2(8) = 387.13, p < 0.001) de la conducta suicida fueron problemas afectivos/depresión, problemas conductuales, problemas somáticos, problemas oposicionistas desafiantes y problemas de ansiedad. CONCLUSIÓN: Cinco problemas de salud mental incrementaron el riesgo de reportar conductas suicidas.


Assuntos
Transtornos Mentais , Ideação Suicida , Tentativa de Suicídio , Humanos , Adolescente , Feminino , México/epidemiologia , Masculino , Tentativa de Suicídio/estatística & dados numéricos , Tentativa de Suicídio/psicologia , Transtornos Mentais/epidemiologia , Criança , Adulto Jovem , Fatores de Risco , Estudos Transversais
15.
Cell Commun Signal ; 22(1): 221, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594674

RESUMO

VEGFR2 (Vascular endothelial growth factor receptor 2) is a central regulator of placental angiogenesis. The study of the VEGFR2 proteome of chorionic villi at term revealed its partners MDMX (Double minute 4 protein) and PICALM (Phosphatidylinositol-binding clathrin assembly protein). Subsequently, the oxytocin receptor (OT-R) and vasopressin V1aR receptor were detected in MDMX and PICALM immunoprecipitations. Immunogold electron microscopy showed VEGFR2 on endothelial cell (EC) nuclei, mitochondria, and Hofbauer cells (HC), tissue-resident macrophages of the placenta. MDMX, PICALM, and V1aR were located on EC plasma membranes, nuclei, and HC nuclei. Unexpectedly, PICALM and OT-R were detected on EC projections into the fetal lumen and OT-R on 20-150 nm clusters therein, prompting the hypothesis that placental exosomes transport OT-R to the fetus and across the blood-brain barrier. Insights on gestational complications were gained by univariable and multivariable regression analyses associating preeclampsia with lower MDMX protein levels in membrane extracts of chorionic villi, and lower MDMX, PICALM, OT-R, and V1aR with spontaneous vaginal deliveries compared to cesarean deliveries before the onset of labor. We found select associations between higher MDMX, PICALM, OT-R protein levels and either gravidity, diabetes, BMI, maternal age, or neonatal weight, and correlations only between PICALM-OT-R (p < 2.7 × 10-8), PICALM-V1aR (p < 0.006), and OT-R-V1aR (p < 0.001). These results offer for exploration new partnerships in metabolic networks, tissue-resident immunity, and labor, notably for HC that predominantly express MDMX.


Assuntos
Diabetes Mellitus , Pré-Eclâmpsia , Feminino , Humanos , Recém-Nascido , Gravidez , Número de Gestações , Ocitocina/metabolismo , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Proteômica , Receptores de Ocitocina/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
16.
J Infect Dev Ctries ; 18(1): 145-151, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38377102

RESUMO

INTRODUCTION: Hepatitis B virus and human immunodeficiency virus (HBV/HIV) co-infection is a global health concern due to its significant impact on morbidity and mortality. Reports of HBV/HIV co-infections are increasing in Nigeria, but information on the disease burden in pregnant women and its implications on the fetus is scarce. This study aimed to determine the prevalence of HBV/HIV co-infection in pregnant women. In addition, the study identified the risk factors for the disease in pregnant women attending antenatal clinics in Osun State, Nigeria. METHODOLOGY: We collected plasma samples from 303 consenting pregnant women and used enzyme-linked immunosorbent assay (ELISA) to test for HBV (HBsAg) and HIV I/II antigens. We obtained demographic and risk factor data on HBV and HIV transmission using a structured questionnaire. RESULTS: Our analysis revealed a prevalence of 3.96% for HBV/HIV co-infection in pregnant women. Bivariate analysis indicated a history of blood transfusion, oral or anal sex, and multiple sexual partners may be associated with an increased likelihood of HBV/HIV co-infection in pregnant women. After adjusting for other variables in multivariate analysis, none of these risk factors were significant at the 5% level. In contrast, formal education was a potential preventive factor in this population. CONCLUSIONS: Our study provides valuable information on the disease burden of HBV/HIV co-infection in pregnant women in Osun State, Nigeria, highlighting the importance of routine screening for HBV and HIV during antenatal care and emphasizing the importance of implementing preventive measures to reduce the morbidity and mortality associated with HBV/HIV co-infection.


Assuntos
Coinfecção , Infecções por HIV , Hepatite B , Complicações Infecciosas na Gravidez , Feminino , Humanos , Gravidez , Vírus da Hepatite B , Coinfecção/epidemiologia , Gestantes , Estudos Soroepidemiológicos , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Nigéria/epidemiologia , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , HIV , Antígenos Virais , Antígenos de Superfície da Hepatite B
17.
Gac. méd. Méx ; 160(1): 36-42, ene.-feb. 2024. tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1557801

RESUMO

Resumen Antecedentes: Las conductas suicidas en adolescentes son un problema de salud pública que va en aumento. Conocer sus factores de riesgo es clave para reducirlas. Objetivo: Identificar la relación entre dos conductas suicidas (ideación e intento) y ocho problemas de salud mental (PSM) en adolescentes mexicanos. Material y métodos: Mediante una encuesta en línea a adolescentes escolarizados de 20 estados, se tamizó la siguiente información: sintomatología de seis PSM (problemas afectivos/depresión, problemas conductuales, problemas somáticos, problemas de inatención e hiperactividad, problemas oposicionistas desafianes y problemas de ansiedad) y conducta suicida (ideación e intentos de suicidio). Se analizaron frecuencias y porcentajes y se indagó asociación mediante regresión logística binaria. Resultados: Completaron la encuesta 6766 adolescentes entre 11 y 19 años (16.38 ± 1.33), 61.02 % del sexo femenino. El 10 % reportó conducta suicida y entre 3 y 5 %, PSM. Los factores predictivos (χ2(8) =387.13, p < 0.001) de la conducta suicida fueron problemas afectivos/depresión, problemas conductuales, problemas somáticos, problemas oposicionistas desafiantes y problemas de ansiedad. Conclusión: Cinco problemas de salud mental incrementaron el riesgo de reportar conductas suicidas.


Abstract Background: Suicidal behavior in adolescents is a growing public health problem. Knowing its risk factors is key for reducing it. Objective: To identify the relationship between two suicidal behaviors (ideation and attempt) and eight mental health problems (MHPs) in Mexican adolescents. Material and methods: Through an online survey of adolescent students from 20 states, the following information was screened: symptomatology of six MHPs (affective problems/depression, behavioral problems, somatic problems, inattention and hyperactivity problems, oppositional defiant problems and anxiety problems) and suicidal behavior (suicidal ideation and suicide attempts). MHP and suicidal behavior frequencies and percentages were analyzed, and associations were sought using binary logistic regression. Results: Six-thousand seven hundred sixty-six adolescents completed the survey, out of whom 61.02% were females, with ages ranging between 11 and 19 years (16.38 ± 1.33); 10% reported suicidal behavior, and between 3 and 5%, MHPs. The predictors (χ2(8) = 387.13, p < 0.001) of suicidal behavior were affective problems/depression, behavioral problems, somatic problems, oppositional defiant problems and anxiety problems. Conclusions: Five mental health problems increased the risk of reporting suicidal behaviors.

18.
Front Cell Infect Microbiol ; 13: 1321315, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38116136

RESUMO

Aim: To characterize the lung microbiome in the bronchoalveolar lavage fluid (BALF) of patients with Antisynthetase Syndrome (ASSD) according to anti-Jo1 autoantibody positivity and evaluate the correlation with differential cell count and other bacterial genera in BALF. Methods: We sequenced the 16S ribosomal RNA gene in the BALF of anti-Jo1-positive (JoP, n=6) and non-Jo1-positive (NJo, n=17) patients, and the differential cell count in BALF was evaluated. The Spearman's correlation was calculated for the quantitative variables and abundance of bacterial species. Results: The Veillonella genus showed a significant decrease (p<0.01) in JoP (2.2%) in comparison to NJo (4.1%) patients. The correlation analysis showed several high (rho ≥ ± 0.7) and significant (p < 0.05) correlations. We analyzed the results obtained for the Veillonella genera and other study variables. The JoP group showed that the abundance of Veillonella had a high negative correlation with macrophages (rho = - 0.77) and a positive correlation with eosinophils (rho = 0.77), lymphocytes (rho = 0.77), and Prevotella (rho = 1). Conclusions: The lung microbiome in ASSD patients differs and may affect cell composition, contributing to lung damage mechanisms. The presence of anti-Jo1 autoantibodies showed a low abundance of Veillonella. This genus had a strong and positive correlation with Prevotella abundance and levels of eosinophils and lymphocytes, and it showed a strong negative correlation with the percentage of macrophages.


Assuntos
Doenças Pulmonares Intersticiais , Miosite , Humanos , Pulmão , Autoanticorpos
19.
Plants (Basel) ; 12(22)2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-38005736

RESUMO

Anthropogenic disturbance of tropical humid forests leads to habitat loss, biodiversity decline, landscape fragmentation, altered nutrient cycling and carbon sequestration, soil erosion, pest/pathogen outbreaks, among others. Nevertheless, the impact of these alterations in multitrophic interactions, including host-pathogen and vector-pathogen dynamics, is still not well understood in wild plants. This study aimed to provide insights into the main drivers for the incidence of herbivory and plant pathogen damage, specifically, into how vegetation traits at the local and landscape scale modulate such interactions. For this purpose, in the tropical forest of Calakmul (Campeche, Mexico), we characterised the foliar damage caused by herbivores and pathogens in woody vegetation of 13 sampling sites representing a gradient of forest disturbance and fragmentation in an anthropogenic landscape from well preserved to highly disturbed and fragmented areas. We also evaluated how the incidence of such damage was modulated by the vegetation and landscape attributes. We found that the incidence of damage caused by larger, mobile, generalist herbivores, was more sensitive to changes in landscape configuration, while the incidence of damage caused by small and specialised herbivores with low dispersal capacity was more influenced by vegetation and landscape composition. In relation to pathogen symptoms, the herbivore-induced foliar damage seems to be the main factor related to their incidence, indicating the enormous importance of herbivorous insects in the modulation of disease dynamics across tropical vegetation, as they could be acting as vectors and/or facilitating the entry of pathogens by breaking the foliar tissue and the plant defensive barriers. The incidence of pathogen damage also responded to vegetation structure and landscape configuration; the incidence of anthracnose, black spot, and chlorosis, for example, were favoured in sites surrounded by smaller patches and a higher edge density, as well as those with a greater aggregation of semi-evergreen forest patches. Fungal pathogens were shown to be an important cause of foliar damage for many woody species. Our results indicate that an increasing transformation and fragmentation of the tropical forest of southern Mexico could reduce the degree of specialisation in plant-herbivore interactions and enhance the proliferation of generalist herbivores (chewers and scrapers) and of mobile leaf suckers, and consequently, the proliferation of some symptoms associated with fungal pathogens such as fungus black spots and anthracnose. The symptoms associated with viral and bacterial diseases and to nutrient deficiency, such as chlorosis, could also increase in the vegetation in fragmented landscapes with important consequences in the health and productivity of wild and cultivated plant species. This is a pioneering study evaluating the effect of disturbances on multitrophic interactions, offering key insights on the main drivers of the changes in herbivory interactions and incidence of plant pathogens in tropical forests.

20.
Polymers (Basel) ; 15(20)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37896379

RESUMO

Mixed matrix membranes (MMMs) provide the opportunity to test new porous materials in challenging applications. A series of low-cost porous organic polymer (POPs) networks, possessing tunable porosity and high CO2 uptake, has been obtained by aromatic electrophilic substitution reactions of biphenyl, 9,10-dihydro-9,10-dimethyl-9,10-ethanoanthracene (DMDHA), triptycene and 1,3,5-triphenylbenzene (135TPB) with dimethoxymethane (DMM). These materials have been characterized by FTIR, 13C NMR, WAXD, TGA, SEM, and CO2 uptake. Finally, different loadings of these POPs have been introduced into Matrimid, Pebax, and chitosan:polyvinyl alcohol blends as polymeric matrices to prepare MMMs. The CO2/CH4 separation performance of these MMMs has been evaluated by single and mixed gas permeation experiments at 4 bar and room temperature. The effect of the porosity of the porous fillers on the membrane separation behavior and the compatibility between them and the different polymer matrices on membrane design and fabrication has been studied by Maxwell model equations as a function of the gas permeability of the pure polymers, porosity, and loading of the fillers in the MMMs. Although the gas transport properties showed an increasing deviation from ideal Maxwell equation prediction with increasing porosity of the POP fillers and increasing hydrophilicity of the polymer matrices, the behavior of biopolymer-based CS:PVA MMMs approached that of Pebax-based MMMs, giving scope to not only new filler materials but also sustainable polymer choices to find a place in membrane technology.

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