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1.
Heliyon ; 10(16): e35911, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39253153

RESUMEN

The recent emergence of innovative learning spaces, Future Classroom Lab (FCL), provides educators the use of physical learning spaces (to research, interact, exchange, develop, create, and present) and diverse technological tools to work according to active methodologies. Learners become more active in the learning process with the introduction of innovative learning environments that enable the application of interdisciplinary STEAM methodology and foster the development of 21st century competences. This study aims to uncover the probable link between application active and gamified STEAM educational interventions in the FCL and Pre-Service Teachers' (PSTs) affective domain. The findings obtained showed statistically significant variations and, therefore, positive effects on the PSTs' affective domain (self-efficacy, attitude, and emotion) after performing the intervention. The sample consisted of a total of 54 PSTs enrolled in the second year of Primary Education. Limited studies regarding the affective domain in the FCL were found, which restricted the comparison with prior research. This study has several implications, such as the introduction of innovative educational proposals to PSTs at the university level and, consequently, the implementation of similar interventions in elementary schools. This research intended to reveal how the different variables work as a support system for students' learning process in mathematics and science disciplines.

2.
Contemp Clin Trials ; 146: 107690, 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39265780

RESUMEN

INTRODUCTION: Ukraine has high HIV prevalence, concentrated among people who inject drugs (PWID), mostly of opioids. Maintenance on opioid agonist therapies (OAT) is the most effective evidence-based treatment for opioid use disorder. As PWID experience high morbidity and mortality from preventable and treatable non-communicable diseases, international agencies recommend integrating OAT into primary care centers (PCC). METHODS: A randomized, type-2 hybrid implementation trial was carried out to compare outcomes of OAT integration in PCC to OAT delivery at specialty treatment centers (STC) - standard-of-care. Tele-education supporting PCC providers in managing OAT, HIV, tuberculosis and non-communicable diseases along with pay-for-performance incentives were used to facilitate implementation. Consenting patients underwent 1:2 randomization to either STC or PCC. Quality health indicators (QHIs), a composite percentage of recommended primary and specialty services accessed by patients (blood/urine tests, cancer screenings, etc.), were defined as efficacy outcomes and were assessed by participant self-report at baseline and every 6 months over 24 months and electronic chart reviews after the completion of the follow-up. The primary outcome is defined as the difference in composite QHI scores at 24 months, in which a repeated measures likelihood-based mixed model with missing at random assumptions will be used. Providers at PCC completed surveys at baseline, 12 and 24 months to assess implementation outcomes including changes in stigma and attitudes towards OAT and PWID. PRELIMINARY RESULTS: Among the 1459 participants allocated to STC (N = 509) or PCC (N = 950), there were no differences in clinical and demographic characteristics. Self-reported prevalences were available for HIV (42 %), HCV (57 %), and prior tuberculosis (17 %). Study retention at 6, 12, 18, and 24 months was as 91 %, 85 %, 80 %, and 74 %, respectively. CONCLUSION: PWID have a high prevalence of medical comorbidities and integrating OAT into primary care settings has the potential to improve the health of PWID. Findings from this study can help guide implementation of integrated care in Ukraine and throughout similar low-resource, high-burden countries in the Eastern European and Central Asian region.

4.
Tree Physiol ; 44(9)2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39163264

RESUMEN

Understanding covariation patterns of drought resistance, post-drought recovery and phenotypic plasticity, and their variability at the intra-population level are crucial for predicting forest vulnerability to increasing aridity. This knowledge is particularly urgent at the trailing range edge since, in these areas, tree species are proximal to their ecological niche boundaries. While this proximity increases their susceptibility, these populations are recognized as valuable genetic reservoirs against environmental stressors. The conservation of this genetic variability is critical for the adaptive capacity of the species in the current context of climate change. Here we examined intra-population patterns of stem basal growth, gas exchange and other leaf functional traits in response to an experimental drought in seedlings of 16 open-pollinated families within a marginal population of European beech (Fagus sylvatica L.) from its southern range edge. We found a high degree of intra-population variation in leaf functional traits, photosynthetic performance, growth patterns and phenotypic plasticity in response to water availability. Low phenotypic plasticity was associated with higher resistance to drought. Both drought resistance and post-drought recovery of photosynthetic performance varied between maternal lines. However, drought resistance and post-drought recovery exhibited independent variation. We also found intra-population variation in stomatal sensitivity to soil drying, but it was not associated with either drought resistance or post-drought recovery. We conclude that an inverse relationship between phenotypic plasticity and drought resistance is not necessarily a sign of maladaptive plasticity, but rather it may reflect stability of functional performance and hence adaptation to withstand drought. The independent variation found between drought resistance and post-drought recovery should facilitate to some extent microevolution and adaption to increasing aridity. The observed variability in stomatal sensitivity to soil drying was consistent with previous findings at other scales (e.g., inter-specific variation, inter-population variation) that challenge the iso-anisohydric concept as a reliable surrogate of drought tolerance.


Asunto(s)
Sequías , Fagus , Fenotipo , Fagus/fisiología , Fagus/genética , Hojas de la Planta/fisiología , Adaptación Fisiológica , Fotosíntesis/fisiología , Cambio Climático , Resistencia a la Sequía
6.
CMAJ ; 196(28): E965-E972, 2024 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-39187289

RESUMEN

BACKGROUND: Public funding of cataract surgery provided in private, for-profit surgical centres increased to help mitigate surgical backlogs during the COVID-19 pandemic in Ontario, Canada. We sought to compare the socioeconomic status of patients who underwent cataract surgery in not-for-profit public hospitals with those who underwent this surgery in private for-profit surgical centres and to evaluate whether differences in access by socioeconomic status decreased after the infusion of public funding for private, for-profit centres. METHODS: We conducted a population-based study of all cataract operations in Ontario, Canada, between January 2017 and March 2022. We analyzed differences in socioeconomic status among patients who accessed surgery at not-for-profit public hospitals versus those who accessed it at private for-profit surgical centres before and during the period of expanded public funding for private for-profit centres. RESULTS: Overall, 935 729 cataract surgeries occurred during the study period. Within private for-profit surgical centres, the rate of cataract surgeries rose 22.0% during the funding change period for patients in the highest socioeconomic status quintile, whereas, for patients in the lowest socioeconomic status quintile, the rate fell 8.5%. In contrast, within public hospitals, the rate of surgery decreased similarly among patients of all quintiles of socioeconomic status. During the funding change period, 92 809 fewer cataract operations were performed than expected. This trend was associated with socioeconomic status, particularly within private for-profit surgical centres, where patients with the highest socioeconomic status were the only group to have an increase in cataract operations. INTERPRETATION: After increased public funding for private, for-profit surgical centres, patient socioeconomic status was associated with access to cataract surgery in these centres, but not in public hospitals. Addressing the factors underlying this incongruity is vital to ensure access to surgery and maintain public confidence in the cataract surgery system.


Asunto(s)
Extracción de Catarata , Accesibilidad a los Servicios de Salud , Clase Social , Humanos , Extracción de Catarata/economía , Extracción de Catarata/estadística & datos numéricos , Ontario , Accesibilidad a los Servicios de Salud/economía , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Masculino , Anciano , Femenino , Persona de Mediana Edad , Financiación Gubernamental/estadística & datos numéricos , Hospitales Públicos/economía , COVID-19/epidemiología , Hospitales con Fines de Lucro/economía , Hospitales con Fines de Lucro/estadística & datos numéricos , SARS-CoV-2 , Anciano de 80 o más Años
7.
Exp Gerontol ; 194: 112511, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38964430

RESUMEN

BACKGROUND: Physical activity has shown beneficial effects for a good state of muscles in aging, but the specific activities of daily living that could be protective remains unclear. This study aimed to analyse the associations of different pattern-recognition-measured daily activities with sarcopenia and sarcopenic obesity in a sample of older adults. METHODS: 200 community-dwelling older adults wore the Intelligent Device for Energy Expenditure and Activity for two consecutive days. Twelve major daily activities recorded were merged in to three common intensity categories: sedentary behaviour (SB), light physical activity (LPA) and moderate-to-vigorous physical activity (MVPA). For physical performance measurements included, hand grip dynamometer and chair-stand tests were used. Skeletal muscle mass and fat mass were estimated by bioelectrical impedance analysis. Associations of daily activities with the study variables were examined using linear regression models. RESULTS: There were no significant associations between total time spent in SB, LPA, or MVPA and sarcopenia. Sarcopenic obesity showed a negative association with total time spent in MVPA [ß (95%CI): -0.29 (-0.41, -0.17)]. Walk at a brisk pace was significatively associated with lower limb physical performance, muscle mass and fat mass % [ß (95%CI): 1.15 (0.40, 1.91); 1.45 (0.68, 2.22) and -2.63 (-4.12, -1.14) respectively]. Other MVPA activities were also significatively associated with the same sarcopenic obesity components [ß (95%CI): 4.65 (0.55, 8.75); 8.59 (4.51, 12.67) and -13.98 (-21.96, -5.99) respectively]. CONCLUSION: Time spent in daily activities of moderate-to-vigorous intensity is negatively associated with sarcopenic obesity but not with sarcopenia.


Asunto(s)
Actividades Cotidianas , Ejercicio Físico , Obesidad , Sarcopenia , Conducta Sedentaria , Humanos , Sarcopenia/fisiopatología , Femenino , Masculino , Anciano , Obesidad/fisiopatología , Obesidad/complicaciones , Ejercicio Físico/fisiología , Anciano de 80 o más Años , Músculo Esquelético/fisiopatología , Fuerza de la Mano , Metabolismo Energético , Vida Independiente
9.
Free Radic Biol Med ; 223: 369-383, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39059513

RESUMEN

Basic Helix-Loop-Helix (bHLH) transcription factors TFEB/TFE3 and HLH-30 are key regulators of autophagy induction and lysosomal biogenesis in mammals and C. elegans, respectively. While much is known about the regulation of TFEB/TFE3, how HLH-30 subcellular dynamics and transactivation are modulated are yet poorly understood. Thus, elucidating the regulation of C. elegans HLH-30 will provide evolutionary insight into the mechanisms governing the function of bHLH transcription factor family. We report here that HLH-30 is retained in the cytoplasm mainly through its conserved Ser201 residue and that HLH-30 physically interacts with the 14-3-3 protein FTT-2 in this location. The FoxO transcription factor DAF-16 is not required for HLH-30 nuclear translocation upon stress, despite that both proteins partner to form a complex that coordinately regulates several organismal responses. Similar as described for DAF-16, the importin IMB-2 assists HLH-30 nuclear translocation, but constitutive HLH-30 nuclear localization is not sufficient to trigger its distinctive transcriptional response. Furthermore, we identify FTT-2 as the target of diethyl maleate (DEM), a GSH depletor that causes a transient nuclear translocation of HLH-30. Together, our work demonstrates that the regulation of TFEB/TFE3 and HLH-30 family members is evolutionarily conserved and that, in addition to a direct redox regulation through its conserved single cysteine residue, HLH-30 can also be indirectly regulated by a redox-dependent mechanism, probably through FTT-2 oxidation.


Asunto(s)
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Oxidación-Reducción , Animales , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Núcleo Celular/metabolismo , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción Forkhead/metabolismo , Factores de Transcripción Forkhead/genética , Proteínas 14-3-3/metabolismo , Proteínas 14-3-3/genética , Autofagia , Transporte de Proteínas , Citoplasma/metabolismo
10.
Sci Rep ; 14(1): 16203, 2024 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-39003322

RESUMEN

Pancreatic ductal adenocarcinoma represents one of the solid tumors showing the worst prognosis worldwide, with a high recurrence rate after adjuvant or neoadjuvant therapy. Circulating tumor DNA analysis raised as a promising non-invasive tool to characterize tumor genomics and to assess treatment response. In this study, surgical tumor tissue and sequential blood samples were analyzed by next-generation sequencing and were correlated with clinical and pathological characteristics. Thirty resectable/borderline pancreatic ductal adenocarcinoma patients treated at the Hospital Universitario de Navarra were included. Circulating tumoral DNA sequencing identified pathogenic variants in KRAS and TP53, and in other cancer-associated genes. Pathogenic variants at diagnosis were detected in patients with a poorer outcome, and were correlated with response to neoadjuvant therapy in borderline pancreatic ductal adneocarcinoma patients. Higher variant allele frequency at diagnosis was associated with worse prognosis, and thesum of variant allele frequency was greater in samples at progression. Our results build on the potential value of circulating tumor DNA for non-metastatic pancreatic ductal adenocarcinoma patients, by complementing tissue genetic information and as a non-invasive tool for treatment decision. Confirmatory studies are needed to corroborate these findings.


Asunto(s)
Carcinoma Ductal Pancreático , ADN Tumoral Circulante , Neoplasias Pancreáticas , Humanos , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/sangre , ADN Tumoral Circulante/genética , ADN Tumoral Circulante/sangre , Masculino , Femenino , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/sangre , Anciano , Persona de Mediana Edad , Pronóstico , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/sangre , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Frecuencia de los Genes , Proteínas Proto-Oncogénicas p21(ras)/genética , Anciano de 80 o más Años , Proteína p53 Supresora de Tumor/genética , Mutación
11.
Clin Invest Med ; 47(2): 4-11, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38958478

RESUMEN

PURPOSE: The COVID-19 pandemic has resulted in a significant diagnostic, screening, and procedure backlog in Ontario. Engagement of key stakeholders in healthcare leadership positions is urgently needed to inform a comprehensive provincial recovery strategy. METHODS: A list of 20 policy recommendations addressing the diagnostic, screening and procedure backlog in Ontario were transformed into a national online survey. Policy recommendations were rated on a 7-point Likert scale (strongly agree to strongly disagree) and organized into those retained (≥75% strongly agree to somewhat agree), discarded (≥80% somewhat disagree to strongly disagree), and no consensus reached. Survey participants included a diverse sample of healthcare leaders with the potential to impact policy reform. RESULTS: Of 56 healthcare leaders invited to participate, there were 34 unique responses (61% response rate). Participants were from diverse clinical backgrounds, including surgical subspecialties, medicine, nursing, and healthcare administration and held institutional or provincial leadership positions. A total of 11 of 20 policy recommendations reached the threshold for consensus agreement with the remaining 9 having no consensus reached. CONCLUSION: Consensus agreement was reached among Canadian healthcare leaders on 11 policy recommendations to address the diagnostic, screening, and procedure backlog in Ontario. Recommendations included strategies to address patient information needs on expected wait times, expand health and human resource capacity, and streamline efficiencies to increase operating room output. No consensus was reached on the optimal funding strategy within the public system in Ontario or the appropriateness of implementing private funding models.


Asunto(s)
COVID-19 , Pandemias , SARS-CoV-2 , Humanos , COVID-19/epidemiología , COVID-19/diagnóstico , Ontario/epidemiología , Encuestas y Cuestionarios , Liderazgo , Tamizaje Masivo , Atención a la Salud , Masculino , Femenino , Personal de Salud
12.
J Neurooncol ; 169(3): 457-467, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38896356

RESUMEN

PURPOSE: A systematic review was conducted to investigate differences in incidence and primary origin of synchronous brain metastasis (sBM) in varying racial groups with different primary cancers. METHODS: Adhering to PRISMA 2020 guidelines a search was conducted using PubMed and Ovid databases for publications from January 2000 to January 2023, with search terms including combinations of "brain metastasis," "race," "ethnicity," and "incidence." Three independent reviewers screened for inclusion criteria encompassing studies clearly reporting primary cancer sites, patient demographics including race, and synchronous BM (sBM) incidence. RESULTS: Of 806 articles, 10 studies comprised of mainly adult patients from the United States met final inclusion for data analysis. Higher sBM incidence proportions were observed in American Indian/Alaska native patients for primary breast (p < 0.001), colorectal (p = 0.015), and esophageal cancers (p = 0.024) as well as in Asian or Pacific islanders for primary stomach (p < 0.001), thyroid (p = 0.006), and lung/bronchus cancers (p < 0.001) yet higher proportions in White patients for malignant melanoma (p < 0.001). Compared to White patients, Black patients had higher sBM incidence likelihood in breast cancer (OR = 1.27, p = 0.01) but lower likelihood in renal (OR = 0.46, p < 0.001) and esophageal cancers (OR = 0.31, p = 0.005). American Indian/Alaska native patients had a higher sBM likelihood (OR = 3.78, p = 0.004) relative to White patients in esophageal cancer. CONCLUSIONS: These findings reveal several comparative racial differences in sBM incidence arising from different primary cancer origins, underscoring a need for further research to explain these variations. Identifying the factors contributing to these disparities holds the potential to promote greater equity in oncological care according to cancer type.


Asunto(s)
Neoplasias Encefálicas , Humanos , Incidencia , Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/epidemiología , Grupos Raciales/estadística & datos numéricos , Neoplasias/patología , Neoplasias/epidemiología
13.
Oper Neurosurg (Hagerstown) ; 27(3): 265-278, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38869495

RESUMEN

BACKGROUND AND OBJECTIVES: Suprasellar tumors, particularly pituitary adenomas (PAs), commonly present with visual decline, and the endoscopic endonasal transsphenoidal approach (EETA) is the primary management for optic apparatus decompression. Patients presenting with complete preoperative monocular blindness comprise a high-risk subgroup, given concern for complete blindness. This retrospective cohort study evaluates outcomes after EETA for patients with PA presenting with monocular blindness. METHODS: Retrospective analysis of all EETA cases at our institution from June 2012 to August 2023 was performed. Inclusion criteria included adults with confirmed PA and complete monocular blindness, defined as no light perception, and a relative afferent pupillary defect secondary to tumor mass effect. RESULTS: Our cohort includes 15 patients (9 males, 6 females), comprising 2.4% of the overall PA cohort screened. The mean tumor diameter was 3.8 cm, with 6 being giant PAs (>4 cm). The mean duration of preoperative monocular blindness was 568 days. Additional symptoms included contralateral visual field defects (n = 11) and headaches (n = 10). Two patients presented with subacute PA apoplexy. Gross total resection was achieved in 46% of patients, reflecting tumor size and invasiveness. Postoperatively, 2 patients experienced improvement in their effectively blind eye and 2 had improved visual fields of the contralateral eye. Those with improvements were operated within 10 days of presentation, and no patients experienced worsened vision. CONCLUSION: This is the first series of EETA outcomes in patients with higher-risk PA with monocular blindness on presentation. In these extensive lesions, vision remained stable for most without further decline and improvement from monocular blindness was observed in a small subset of patients with no light perception and relative afferent pupillary defect. Timing from vision loss to surgical intervention seemed to be associated with improvement. From a surgical perspective, caution is warranted to protect remaining vision and we conclude that EETA is safe in the management of these patients.


Asunto(s)
Adenoma , Ceguera , Neoplasias Hipofisarias , Humanos , Masculino , Neoplasias Hipofisarias/cirugía , Neoplasias Hipofisarias/complicaciones , Neoplasias Hipofisarias/diagnóstico por imagen , Femenino , Ceguera/etiología , Ceguera/cirugía , Persona de Mediana Edad , Adenoma/cirugía , Adenoma/complicaciones , Estudios Retrospectivos , Adulto , Anciano , Neuroendoscopía/métodos , Resultado del Tratamiento , Cirugía Endoscópica por Orificios Naturales/métodos
14.
AIDS Behav ; 28(8): 2755-2768, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38878137

RESUMEN

HIV stigma is a social determinant of health that can influence multiple health outcomes, including adherence to antiretroviral therapy (ART), engagement in HIV care, and viral suppression levels in people with HIV (PWH). In Peru, where the HIV epidemic is concentrated in men who have sex with men (MSM) and transgender women (TGW), stigma may play an important role in healthcare engagement. To understand the relationship between stigma and two outcome variables, ART adherence and engagement in HIV care in 400 MSM and TGW, we assessed factors from the Behavioral Model for Vulnerable Populations at two HIV clinics that tailor services for sexual and gender minorities. While some predisposing, need, and enabling resource factors were associated with optimal (≥ 90%) ART adherence or engagement in HIV care, none of the stigma subscales were correlated, suggesting that when LGBTQ-affirming care is provided to MSM/TGW, stigma may not influence HIV-related outcomes.


RESUMEN: El estigma hacia el VIH es un determinante social de la salud que puede influir en múltiples desenlaces, incluyendo la adherencia a la terapia antirretroviral (TAR), el compromiso con la atención del VIH y los niveles de supresión viral en personas viviendo con VIH (PVV). En el Perú, donde la epidemia del VIH se concentra en hombres que tienen sexo con hombres (HSH) y mujeres transgénero (MT), el estigma puede desempeñar un papel importante en el compromiso con la atención médica. Para comprender la relación entre el estigma y dos variables de resultado, la adherencia al TAR y el compromiso con la atención del VIH en 400 HSH y MT, evaluamos factores del Modelo de Comportamiento para Poblaciones Vulnerables en dos clínicas de VIH que adaptan sus servicios para minorías sexuales y de género. Si bien algunos factores predisponentes, de necesidad y de recursos habilitantes se asociaron con una adherencia óptima (≥ 90%) al TAR o al compromiso con la atención del VIH, ninguna de las sub-escalas de estigma estuvieron correlacionadas, sugiriendo que cuando se brinda atención que afirma a la comunidad LGBTQ a HSH/MT, el estigma puede no influir en los desenlaces relacionados con el VIH.


Asunto(s)
Infecciones por VIH , Homosexualidad Masculina , Cumplimiento de la Medicación , Estigma Social , Personas Transgénero , Humanos , Masculino , Perú/epidemiología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/psicología , Personas Transgénero/psicología , Personas Transgénero/estadística & datos numéricos , Femenino , Adulto , Homosexualidad Masculina/psicología , Homosexualidad Masculina/estadística & datos numéricos , Cumplimiento de la Medicación/psicología , Cumplimiento de la Medicación/estadística & datos numéricos , Fármacos Anti-VIH/uso terapéutico , Persona de Mediana Edad , Estudios Transversales , Adulto Joven , Minorías Sexuales y de Género/psicología , Minorías Sexuales y de Género/estadística & datos numéricos
16.
J Med Chem ; 67(13): 11242-11253, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38935616

RESUMEN

We report the [natMn/52Mn]Mn(II) complexes of the macrocyclic chelators PYAN [3,6,10,13-tetraaza-1,8(2,6)-dipyridinacyclotetradecaphane] and CHXPYAN [(41R,42R,101R,102R)-3,5,9,11-tetraaza-1,7(2,6)-dipyridina-4,10(1,2)-dicyclohexanacyclododecaphane]. The X-ray crystal structures of Mn-PYAN and Mn-CHXPYAN evidence distorted octahedral geometries through coordination of the nitrogen atoms of the macrocycles. Cyclic voltammetry studies evidence reversible processes due to the Mn(II)/Mn(III) pair, indicating that the complexes are resistant to oxidation. CHXPYAN forms a more thermodynamically stable and kinetically inert Mn(II) complex than PYAN. Radiochemical studies with the radioactive isotope manganese-52 (52Mn, t1/2 = 5.6 days) evidenced better radiochemical yields for CHXPYAN than for PYAN. Both [52Mn]Mn(II) complexes remained stable in mouse and human serum, so in vivo stability studies were carried out. Positron emission tomography/computed tomography scans and biodistribution assays indicated that [52Mn]Mn-PYAN has a distribution pattern similar to that of [52Mn]MnCl2, showing persistent radioactivity accumulation in the kidneys. Conversely, [52Mn]Mn-CHXPYAN remained stable in vivo, clearing quickly from the liver and kidneys.


Asunto(s)
Quelantes , Compuestos Macrocíclicos , Manganeso , Tomografía de Emisión de Positrones , Animales , Ratones , Tomografía de Emisión de Positrones/métodos , Compuestos Macrocíclicos/química , Compuestos Macrocíclicos/síntesis química , Compuestos Macrocíclicos/farmacocinética , Manganeso/química , Quelantes/química , Quelantes/síntesis química , Cristalografía por Rayos X , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Complejos de Coordinación/farmacocinética , Distribución Tisular , Modelos Moleculares , Radiofármacos/química , Radiofármacos/síntesis química , Radiofármacos/farmacocinética , Estabilidad de Medicamentos
17.
Inorg Chem ; 63(25): 11884-11896, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38861670

RESUMEN

We provide a comprehensive study of the coordination of oxocyclam with palladium(II), including presentation of a novel bifunctional analogue, p-H2N-Bn-oxocyclam, bearing an aniline pendant. The complexation of palladium(II) with oxocyclam was examined by various techniques, including NMR analysis and potentiometric titrations which revealed that the Pd(II) complex can adopt different configurations such as trans-I and trans-III. In addition, oxocyclam forms a thermodynamically stable palladium(II) complex, the stabilization being attributed to the deprotonation of the amide function. The crystal structures of [Pd(H-1oxocyclam)]+ and [Pd(oxocyclam)]2+ were obtained, revealing the structural details previously anticipated, including, in the second case, the presence of the proton on the carbonyl oxygen atom. Additionally, the study explored the redox behavior of the Pd(II)-oxocyclam complex through reduction and oxidation voltammograms at different pH values. Successful 109Pd-labeling of oxocyclam and p-H2N-Bn-oxocyclam at pH 3.5 demonstrated high labeling efficiencies, whatever the species formed. The stability of the radiocomplexes was assessed and moderate transchelation toward EDTA was observed. Overall, oxocyclam displayed favorable properties for Pd(II) coordination and radiolabeling, suggesting its potential as a chelating agent for this metal in palladium-based applications.

18.
iScience ; 27(6): 110069, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38868201

RESUMEN

Astrocyte endfeet enwrap brain vasculature, forming a boundary for perivascular glymphatic flow of fluid and solutes along and across the astrocyte endfeet into the brain parenchyma. We evaluated astrocyte sensitivity to shear stress generated by such flow, finding a set point for downstream calcium signaling that is below about 0.1 dyn/cm2. This set point is modulated by albumin levels encountered in cerebrospinal fluid (CSF) under normal conditions and following a blood-brain barrier breach or immune response. The astrocyte mechanosome responsible for the detection of shear stress includes sphingosine-1-phosphate (S1P)-mediated sensitization of the mechanosensor Piezo1. Fluid flow through perivascular channels delimited by vessel wall and astrocyte endfeet thus generates sufficient shear stress to activate astrocytes, thereby potentially controlling vasomotion and parenchymal perfusion. Moreover, S1P receptor signaling establishes a set point for Piezo1 activation that is finely tuned to coincide with CSF albumin levels and to the low shear forces resulting from glymphatic flow.

19.
EMBO J ; 43(13): 2789-2812, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38811853

RESUMEN

It has remained unknown how cells reduce cystine taken up from the extracellular space, which is a required step for further utilization of cysteine in key processes such as protein or glutathione synthesis. Here, we show that the thioredoxin-related protein of 14 kDa (TRP14, encoded by TXNDC17) is the rate-limiting enzyme for intracellular cystine reduction. When TRP14 is genetically knocked out, cysteine synthesis through the transsulfuration pathway becomes the major source of cysteine in human cells, and knockout of both pathways becomes lethal in C. elegans subjected to proteotoxic stress. TRP14 can also reduce cysteinyl moieties on proteins, rescuing their activities as here shown with cysteinylated peroxiredoxin 2. Txndc17 knockout mice were, surprisingly, protected in an acute pancreatitis model, concomitant with activation of Nrf2-driven antioxidant pathways and upregulation of transsulfuration. We conclude that TRP14 is the evolutionarily conserved enzyme principally responsible for intracellular cystine reduction in C. elegans, mice, and humans.


Asunto(s)
Caenorhabditis elegans , Cisteína , Cistina , Ratones Noqueados , Oxidación-Reducción , Proteoma , Tiorredoxinas , Animales , Humanos , Ratones , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Cisteína/metabolismo , Cistina/metabolismo , Peroxirredoxinas/metabolismo , Peroxirredoxinas/genética , Proteoma/metabolismo , Tiorredoxinas/metabolismo , Tiorredoxinas/genética
20.
Rev Esp Enferm Dig ; 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38775394

RESUMEN

Lymphoepithelioma-like carcinoma (LELC) is a histological variant that resembles nasopharyngeal lymphoepithelioma and occurs in various locations such as the salivary glands and lung. LELCs in the digestive tract are rare, accounting for only 2% of cases, being exceptional in the rectum. We present the case of an 84-year-old man with rectorrhagia, whitish malodorous discharge and constipation of one month's duration. Rectal examination identified a tumour. Colonoscopy revealed a rectal lesion that was confirmed by biopsy as malignant, and MRI showed an extensive rectal tumour. Histopathology revealed undifferentiated carcinoma with acute inflammatory infiltrate, consistent with LELC. Immunohistochemistry was positive for keratins 5/6, 18, 20, CEA and BER.EP4, while in situ hybridisation for Epstein-Barr virus (EBV) RNA was negative. The multidisciplinary decision included neoadjuvant radiotherapy and anterior rectal resection. The patient remains in complete response two years after treatment. Histologically, LELC is characterised by an acute inflammatory infiltrate interspersed with poorly differentiated neoplastic cells. The stomach is the most commonly affected region in the gastrointestinal tract, with more than 80% of gastric LELCs associated with EBV. To date, only four cases of rectal LELC have been reported, and its association with EBV was demonstrated in only one case. There are no standard treatments for rectal LELC, underscoring the need to gather more cases to understand its pathogenesis and develop effective treatment strategies.

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