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1.
J Natl Compr Canc Netw ; : 1-8, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38996438

RESUMEN

BACKGROUND: The overall landscape of health-related quality of life (HRQoL) has not been thoroughly investigated in adolescents and young adults (AYAs) with cancer. Data are also lacking on how well HRQoL at the time of cancer diagnosis can prognosticate long-term survival in AYA survivors. PATIENTS AND METHODS: We included 3,497 survivors of AYA cancer (age 15-39 years at diagnosis) who completed the Short-Form 12 Health Survey (SF-12) HRQoL questionnaire at diagnosis. Physical component summary (PCS) and mental component summary (MCS) scores were generated, with scores <50 representing poor HRQoL. Differences in HRQoL by patient characteristics and tumor type were investigated using violin plots and t tests/analysis of variance. The effect of HRQoL on overall survival was assessed using Kaplan-Meier plots and Cox proportional hazards models. RESULTS: Overall mean PCS and MCS scores in this racially/ethnically diverse cohort (64% White, 19% Hispanic, 10% Black, and 7% other race/ethnicity) were 43.6 and 46.7, respectively. Women with breast cancer reported the most favorable PCS (50.8), and those with cervical cancer reported the lowest MCS (42.8). Age at diagnosis was associated positively with PCS (P<.001) and inversely with MCS (P<.001). Females had higher PCS yet lower MCS than males (both P<.001). Marginalized racial and ethnic populations reported lower PCS than White patients (P<.001). Physical and mental HRQoL were prognostic and associated with increased risk of poor survival (hazard ratio, 1.95; 95% CI, 1.72-2.21 for physical HRQoL, and 1.26; 95% CI, 1.13-1.40 for mental HRQoL). CONCLUSIONS: Physical and mental HRQoL at diagnosis vary across patient characteristics in AYA cancer survivors. Poor HRQoL at diagnosis may be a prognosticator of diminished overall survival among AYA cancer survivors.

2.
Int J Mol Sci ; 25(13)2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38999960

RESUMEN

The initial adoption of penicillin as an antibiotic marked the start of exploring other compounds essential for pharmaceuticals, yet resistance to penicillins and their side effects has compromised their efficacy. The N-terminal nucleophile (Ntn) amide-hydrolases S45 family plays a key role in catalyzing amide bond hydrolysis in various compounds, including antibiotics like penicillin and cephalosporin. This study comprehensively analyzes the structural and functional traits of the bacterial N-terminal nucleophile (Ntn) amide-hydrolases S45 family, covering penicillin G acylases, cephalosporin acylases, and D-succinylase. Utilizing structural bioinformatics tools and sequence analysis, the investigation delineates structurally conserved regions (SCRs) and substrate binding site variations among these enzymes. Notably, sixteen SCRs crucial for substrate interaction are identified solely through sequence analysis, emphasizing the significance of sequence data in characterizing functionally relevant regions. These findings introduce a novel approach for identifying targets to enhance the biocatalytic properties of N-terminal nucleophile (Ntn) amide-hydrolases, while facilitating the development of more accurate three-dimensional models, particularly for enzymes lacking structural data. Overall, this research advances our understanding of structure-function relationships in bacterial N-terminal nucleophile (Ntn) amide-hydrolases, providing insights into strategies for optimizing their enzymatic capabilities.


Asunto(s)
Amidohidrolasas , Amidohidrolasas/química , Amidohidrolasas/metabolismo , Amidohidrolasas/genética , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Sitios de Unión , Relación Estructura-Actividad , Secuencia Conservada , Bacterias/enzimología , Secuencia de Aminoácidos , Modelos Moleculares , Especificidad por Sustrato
3.
Int J Mol Sci ; 25(7)2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38612895

RESUMEN

Expression of miR-21 has been found to be altered in almost all types of cancers, and it has been classified as an oncogenic microRNA. In addition, the expression of tumor suppressor gene RECK is associated with miR-21 overexpression in high-grade cervical lesions. In the present study, we analyze the role of miR-21 in RECK gene regulation in cervical cancer cells. To identify the downstream cellular target genes of upstream miR-21, we silenced endogenous miR-21 expression using siRNAs. We analyzed the expression of miR-21 and RECK, as well as functional effects on cell proliferation and migration. We found that in cervical cancer cells, there was an inverse correlation between miR-21 expression and RECK mRNA and protein expression. SiRNAs to miR-21 increased luciferase reporter activity in construct plasmids containing the RECK-3'-UTR microRNA response elements MRE21-1, MRE21-2, and MRE21-3. The role of miR-21 in cell proliferation was also analyzed, and cancer cells transfected with siRNAs exhibited a markedly reduced cell proliferation and migration. Our findings indicate that miR-21 post-transcriptionally down-regulates the expression of RECK to promote cell proliferation and cell migration inhibition in cervical cancer cell survival. Therefore, miR-21 and RECK may be potential therapeutic targets in gene therapy for cervical cancer.


Asunto(s)
MicroARNs , Neoplasias del Cuello Uterino , Femenino , Humanos , Neoplasias del Cuello Uterino/genética , Transducción de Señal , Proliferación Celular/genética , Movimiento Celular/genética , ARN Interferente Pequeño , MicroARNs/genética , Agitación Psicomotora , ARN Bicatenario , Proteínas Ligadas a GPI/genética
4.
Planta ; 258(1): 20, 2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37326881

RESUMEN

MAIN CONCLUSION: SA and H2O2, in single and mixed elicitation stimulate specialized metabolism and activate oxidative stress in C. tenuiflora plants. Single elicitation with salicylic acid (SA at 75 µM) and, hydrogen peroxide (at 150 µM), and mixed elicitation (75 µM SA + 150 µM H2O2) were evaluated on specialized metabolism in Castilleja tenuiflora Benth. plants. Total phenolic content (TPC), phenylalanine ammonia-lyase (PAL) activity, antioxidant enzymes and specialized metabolite profiles, as well as the expression levels of eight genes involved in phenolic (Cte-TyrDC, Cte-GOT2, Cte-ADD, Cte-AO3, Cte-PAL1, Cte-CHS1) and terpene pathways (Cte-DXS1 and Cte-G10H) and their correlation with major metabolite (verbascoside and aucubin) concentrations were investigated. TPC content (three-fold) and PAL activity (11.5-fold) increased with mixed elicitation, as well as catalase and peroxidase activity (11.3-fold and 10.8-fold, respectively), compared to single elicitation. Phenylethanoid accumulation was greatest under mixed elicitation, followed by SA and H2O2. Lignan accumulation was differential, depending on the plant part and the elicitor. Flavonoids only appeared after mixed elicitation. The high concentration of verbascoside under mixed elicitation was related to a high gene expression. Single elicitation induced iridoid accumulation in specific parts (H2O2 in aerial parts and SA in roots), whereas under mixed elicitation, it accumulated in both parts. A high concentration of aucubin in the aerial part was related to a high expression level of genes of the terpene pathway Cte-DXS1 and Cte-G10H, and in the root with Cte-G10H, while Cte-DXS1 was downregulated in this tissue in all treatments. Mixed elicitation with SA and H2O2 represents an interesting tool to increase the production of specialized metabolites in plants.


Asunto(s)
Peróxido de Hidrógeno , Orobanchaceae , Peróxido de Hidrógeno/metabolismo , Ácido Salicílico/metabolismo , Iridoides , Fenoles/metabolismo , Antioxidantes/metabolismo , Orobanchaceae/metabolismo
5.
BMC Med Educ ; 23(1): 975, 2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38115060

RESUMEN

BACKGROUND: The dentist should have a thorough knowledge of the science, protocols and procedures for dental shade selection in order to mimic dental tissue with restorative materials, respecting the individual needs and attitudes of each patient and providing them with a pleasant and esthetically acceptable appearance. The present study evaluated the knowledge and attitudes of dental interns from two Peruvian universities about dental shade selection and its relationship with sociodemographic factors. METHODS: The present cross-sectional and analytical study was carried out on Peruvian dental interns from the Universidad Nacional Federico Villarreal and the Universidad Privada de San Juan Bautista during May to June 2022. Two validated questionnaires on knowledge and attitudes about dental shade selection were used. A Poisson regression model with robust variance using the adjusted prevalence ratio (APR) was used to assess the influence of the variables: age group, sex, place of origin and type of university, considering a significance level of p<0.05. RESULTS: The results showed that 40.8% (95% CI: 34.0% - 47.6%) of the interns presented unfavorable attitudes while 90.1% (95% CI: 86.0% - 94.2%) presented insufficient knowledge. It was also found that dental interns under 29 years of age were 32% less likely to have unfavorable attitudes (APR = 0.68, 95% CI 0.48 - 0.96) and 11% more likely to have insufficient knowledge (APR = 1.11, 95% CI 1.01 - 1.24) about tooth shade selection compared to dental interns aged 29 years and older. Finally, women were 55% more likely to have unfavorable attitudes about tooth shade selection compared to men (APR = 1.55; 95% CI: 1.08 - 2.22). CONCLUSION: The majority of dental interns presented insufficient knowledge and less than half had unfavorable attitudes about dental shade selection. In addition, being a student under 29 years of age was a risk factor for presenting insufficient knowledge and at the same time constituted a protective factor for presenting unfavorable attitudes. Likewise, being a female student was a risk factor for presenting unfavorable attitudes about dental shade selection.


Asunto(s)
Factores Sociodemográficos , Estudiantes de Odontología , Masculino , Humanos , Femenino , Adulto , Color , Estudios Transversales , Perú
6.
Int J Mol Sci ; 24(18)2023 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-37762475

RESUMEN

Stressed organisms identify intracellular molecules released from damaged cells due to trauma or pathogen infection as components of the innate immune response. These molecules called DAMPs (Damage-Associated Molecular Patterns) are extracellular ATP, sugars, and extracellular DNA, among others. Animals and plants can recognize their own DNA applied externally (self-exDNA) as a DAMP with a high degree of specificity. However, little is known about the microalgae responses to damage when exposed to DAMPs and specifically to self-exDNAs. Here we compared the response of the oilseed microalgae Neochloris oleoabundans to self-exDNA, with the stress responses elicited by nonself-exDNA, methyl jasmonate (MeJA) and sodium bicarbonate (NaHCO3). We analyzed the peroxidase enzyme activity related to the production of reactive oxygen species (ROS), as well as the production of polyphenols, lipids, triacylglycerols, and phytohormones. After 5 min of addition, self-exDNA induced peroxidase enzyme activity higher than the other elicitors. Polyphenols and lipids were increased by self-exDNA at 48 and 24 h, respectively. Triacylglycerols were increased with all elicitors from addition and up to 48 h, except with nonself-exDNA. Regarding phytohormones, self-exDNA and MeJA increased gibberellic acid, isopentenyladenine, and benzylaminopurine at 24 h. Results show that Neochloris oleoabundans have self-exDNA specific responses.


Asunto(s)
Chlorophyceae , Microalgas , Animales , Reguladores del Crecimiento de las Plantas , Peroxidasa , Alarminas , Colorantes , ADN , Oxilipinas , Peroxidasas
7.
Int J Mol Sci ; 25(1)2023 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-38203628

RESUMEN

Psittacanthus calyculatus parasitizes mesquite trees through a specialized structure called a haustorium, which, in the intrusive process, can cause cellular damage in the host tree and release DAMPs, such as ATP, sugars, RNA, and DNA. These are highly conserved molecules that primarily function as signals that trigger and activate the defense responses. In the present study, we generate extracellular DNA (exDNA) from mesquite (P. laevigata) tree leaves (self-exDNA) and P. calyculatus (non-self exDNA) mistletoe as DAMP sources to examine mesquite trees' capacity to identify specific self or non-self exDNA. We determined that mesquite trees perceive self- and non-self exDNA with the synthesis of O2•-, H2O2, flavonoids, ROS-enzymes system, MAPKs activation, spatial concentrations of JA, SA, ABA, and CKs, and auxins. Our data indicate that self and non-self exDNA application differs in oxidative burst, JA signaling, MAPK gene expression, and scavenger systems. This is the first study to examine the molecular biochemistry effects in a host tree using exDNA sources derived from a mistletoe.


Asunto(s)
Muérdago , Prosopis , Alarminas , ADN , Peróxido de Hidrógeno , Árboles
8.
Ann Hum Biol ; 49(7-8): 291-298, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36350847

RESUMEN

BACKGROUND: Plasminogen activator inhibitor 1 (PAI-1) and resistin are associated with dysfunctional adipose tissue (AT)-related metabolic complications. The role of dietary eicosapentaenoic (EPA) and docosahexaenoic (DHA) fatty acids in this relationship is unknown. AIM: To investigate the association of EPA and DHA with PAI-1 and resistin, as well as the role of this association on the glucose metabolism of apparently healthy subjects. SUBJECTS AND METHODS: Thirty-six healthy individuals were included. Validated food frequency questionnaires were used to analyse dietary habits. Inflammatory and glucose metabolism markers were quantified. Subcutaneous AT samples were obtained, and adipocyte number, area, and macrophage content were assessed. RESULTS: In 36 subjects aged 56 ± 8 years and with a body mass index of 26 ± 4 kg/m2, logEPA, and logDHA showed significant association with logresistin and a marginal association with PAI-1. Adipocyte number, area, and lognumber of macrophages per adipocyte significantly correlated with PAI-1 but not with logresistin. Although logEPA and logDHA were independently associated with loginsulin, loginsulin resistance, and C-Peptide, the addition of logresistin, but not of PAI-1, into the multivariable model, abolished the associations. CONCLUSIONS: EPA and DHA could modulate glucose metabolism across AT functional states. Our data indicate that this association is independent of other metabolic risk factors.


Asunto(s)
Ácidos Grasos Omega-3 , Inhibidor 1 de Activador Plasminogénico , Humanos , Inhibidor 1 de Activador Plasminogénico/metabolismo , Resistina/metabolismo , Ácido Eicosapentaenoico/metabolismo , Ácido Eicosapentaenoico/farmacología , Autoinforme , Voluntarios Sanos , Ácidos Docosahexaenoicos/metabolismo , Ácidos Docosahexaenoicos/farmacología , Ácidos Grasos Omega-3/metabolismo , Ácidos Grasos Omega-3/farmacología , Tejido Adiposo/metabolismo , Glucosa/metabolismo
9.
Biochem J ; 477(18): 3599-3612, 2020 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-32869839

RESUMEN

Among the major challenges in the development of biopharmaceuticals are structural heterogeneity and aggregation. The development of a successful therapeutic monoclonal antibody (mAb) requires both a highly active and also stable molecule. Whilst a range of experimental (biophysical) approaches exist to track changes in stability of proteins, routine prediction of stability remains challenging. The fluorescence red edge excitation shift (REES) phenomenon is sensitive to a range of changes in protein structure. Based on recent work, we have found that quantifying the REES effect is extremely sensitive to changes in protein conformational state and dynamics. Given the extreme sensitivity, potentially this tool could provide a 'fingerprint' of the structure and stability of a protein. Such a tool would be useful in the discovery and development of biopharamceuticals and so we have explored our hypothesis with a panel of therapeutic mAbs. We demonstrate that the quantified REES data show remarkable sensitivity, being able to discern between structurally identical antibodies and showing sensitivity to unfolding and aggregation. The approach works across a broad concentration range (µg-mg/ml) and is highly consistent. We show that the approach can be applied alongside traditional characterisation testing within the context of a forced degradation study (FDS). Most importantly, we demonstrate the approach is able to predict the stability of mAbs both in the short (hours), medium (days) and long-term (months). The quantified REES data will find immediate use in the biopharmaceutical industry in quality assurance, formulation and development. The approach benefits from low technical complexity, is rapid and uses instrumentation which exists in most biochemistry laboratories without modification.


Asunto(s)
Anticuerpos Monoclonales/química , Conformación Proteica , Estabilidad Proteica , Espectrometría de Fluorescencia
10.
Biol Blood Marrow Transplant ; 26(6): e135-e137, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32070723

RESUMEN

Telehealth involves the use of telecommunication and information technology for the delivery of clinical care and may be a mechanism to alleviate the burden of visits faced by patients undergoing hematopoietic cell transplantation (HCT). Few studies have evaluated the feasibility and acceptability of telehealth visits in the care of HCT patients. We conducted 27 telehealth visits with 25 patients undergoing HCT using a videoconferencing system that allows for real-time, 2-way interactions and administered satisfaction surveys to patients and providers. Of the 25 patients included in the study, 20 (80%) and 5 (20%) were undergoing autologous and allogeneic HCT, respectively. The telehealth visits were distributed as follows: 3 inpatient visits upon admission for HCT; 11 inpatient visits between 2 and 14 days post-HCT; 4 inpatient visits prior to discharge after HCT; 8 outpatient, post-HCT follow-up visits; and 1 handoff to a community oncologist. Out of a total of 54 provider assessments, 7 providers (13%) were unable to complete some part of the physical examination, but no provider reported being unable to manage patients' symptoms through telehealth. Eighty-one percent of patients were either satisfied or very satisfied with the telemedicine session. Overall satisfaction was higher among patients than providers (mean scores 4.12 versus 2.64; scale 1 to 5, with 1 = very poor to 5 = excellent). Technological barriers resulting in delays and suboptimal physical examination were largely responsible for provider dissatisfaction. The use of telehealth to deliver comprehensive follow-up care to HCT patients is feasible across different HCT types but is dependent upon quality of data streaming and videoconferencing technologies.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Telemedicina , Humanos , Proyectos Piloto , Encuestas y Cuestionarios , Comunicación por Videoconferencia
11.
Rev Chil Pediatr ; 90(4): 411-421, 2019 Aug.
Artículo en Inglés, Español | MEDLINE | ID: mdl-31859714

RESUMEN

OBJECTIVE: To evaluate the impact of a community program aimed at improving the children mal nutrition in a rural community of the State of Chiapas, Mexico, 2013. MATERIAL AND METHOD: Des criptive study of the evaluation program from a secondary database of nutritional data registry of 113 children under five years of age in a rural area of Mexico. The intervention and the survey were carried out during 2013. Baseline and 4-month measurements were recorded. The World Health Organization (WHO) Anthro software was used to calculate nutritional status indicators. According to WHO guidelines, the following data were estimated: weight for age (W/A), height for age (H/A), weight for height (W/H), and Body mass index for age (BMI/A). Position and dispersion measures were calculated; Student's T-test, Kruskal-Wallis, and MacNemar test were used for paired data and linear regression. RESULTS: Between the beginning and the end, the median of the Z W/H went from -0.7 (p25 -1.24, p75 -0.01) to -0.62 (p25 -1.09, p75 -0.15). The prevalence of low weight decreased from 5.31% (CI 2.38-11.44) to 4.42% (CI 1.83-10.32) (Z BMI/A). The appropriate weight according to Z score W/H increased from 78.76% (CI 70.12-85.43) to 84.96% (76.98-90.51). In the subgroup with low initial weight, the mean of Z BMI/A and Z W/H increased 0.4 (p = 0.003). The change in the mean of Z W/H was 0.02 points in the subgroup that received the direct transfer program and of -0.3 in which it did not (p = 0.020). CONCLUSIONS: It is concluded that the community program during the four months of implementation contributed to improve some anthropometric indicators, although no apparent effects were found in indicators related to chronic malnutrition.


Asunto(s)
Trastornos de la Nutrición del Niño/terapia , Servicios de Salud Comunitaria/organización & administración , Estado Nutricional , Población Rural , Antropometría , Estatura , Índice de Masa Corporal , Peso Corporal , Trastornos de la Nutrición del Niño/epidemiología , Preescolar , Femenino , Humanos , Lactante , Estudios Longitudinales , Masculino , México , Prevalencia
12.
Entropy (Basel) ; 20(1)2018 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-33265130

RESUMEN

We calculate the transverse velocity fluctuations correlation function of a linear and homogeneous viscoelastic liquid by using a generalized Langevin equation (GLE) approach. We consider a long-ranged (power-law) viscoelastic memory and a noise with a long-range (power-law) auto-correlation. We first evaluate the transverse velocity fluctuations correlation function for conventional time derivatives C ^ N F ( k → , t ) and then introduce time fractional derivatives in their equations of motion and calculate the corresponding fractional correlation function. We find that the magnitude of the fractional correlation C ^ F ( k → , t ) is always lower than the non-fractional one and decays more rapidly. The relationship between the fractional loss modulus G F ″ ( ω ) and C ^ F ( k → , t ) is also calculated analytically. The difference between the values of G ″ ( ω ) for two specific viscoelastic fluids is quantified. Our model calculation shows that the fractional effects on this measurable quantity may be three times as large as compared with its non-fractional value. The fact that the dynamic shear modulus is related to the light scattering spectrum suggests that the measurement of this property might be used as a suitable test to assess the effects of temporal fractional derivatives on a measurable property. Finally, we summarize the main results of our approach and emphasize that the eventual validity of our model calculations can only come from experimentation.

13.
J Biol Chem ; 290(4): 2334-50, 2015 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-25488663

RESUMEN

The solution structure of complement C3b is crucial for the understanding of complement activation and regulation. C3b is generated by the removal of C3a from C3. Hydrolysis of the C3 thioester produces C3u, an analog of C3b. C3b cleavage results in C3c and C3d (thioester-containing domain; TED). To resolve functional questions in relation to C3b and C3u, analytical ultracentrifugation and x-ray and neutron scattering studies were used with C3, C3b, C3u, C3c, and C3d, using the wild-type allotype with Arg(102). In 50 mm NaCl buffer, atomistic scattering modeling showed that both C3b and C3u adopted a compact structure, similar to the C3b crystal structure in which its TED and macroglobulin 1 (MG1) domains were connected through the Arg(102)-Glu(1032) salt bridge. In physiological 137 mm NaCl, scattering modeling showed that C3b and C3u were both extended in structure, with the TED and MG1 domains now separated by up to 6 nm. The importance of the Arg(102)-Glu(1032) salt bridge was determined using surface plasmon resonance to monitor the binding of wild-type C3d(E1032) and mutant C3d(A1032) to immobilized C3c. The mutant did not bind, whereas the wild-type form did. The high conformational variability of TED in C3b in physiological buffer showed that C3b is more reactive than previously thought. Because the Arg(102)-Glu(1032) salt bridge is essential for the C3b-Factor H complex during the regulatory control of C3b, the known clinical associations of the major C3S (Arg(102)) and disease-linked C3F (Gly(102)) allotypes of C3b were experimentally explained for the first time.


Asunto(s)
Activación de Complemento , Complemento C3/metabolismo , Complemento C3b/metabolismo , Complemento C3c/metabolismo , Complemento C3d/metabolismo , Arginina/química , Cristalografía por Rayos X , Humanos , Macroglobulinas/metabolismo , Mutagénesis , Mutación , Conformación Proteica , Multimerización de Proteína , Dispersión de Radiación , Resonancia por Plasmón de Superficie , Ultracentrifugación
14.
J Biol Chem ; 288(26): 19197-210, 2013 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-23661701

RESUMEN

The sub-retinal pigment epithelial deposits that are a hallmark of age-related macular degeneration contain both C3b and millimolar levels of zinc. C3 is the central protein of complement, whereas C3u is formed by the spontaneous hydrolysis of the thioester bridge in C3. During activation, C3 is cleaved to form active C3b, then C3b is inactivated by Factor I and Factor H to form the C3c and C3d fragments. The interaction of zinc with C3 was quantified using analytical ultracentrifugation and x-ray scattering. C3, C3u, and C3b associated strongly in >100 µM zinc, whereas C3c and C3d showed weak association. With zinc, C3 forms soluble oligomers, whereas C3u and C3b precipitate. We conclude that the C3, C3u, and C3b association with zinc depended on the relative positions of C3d and C3c in each protein. Computational predictions showed that putative weak zinc binding sites with different capacities exist in all five proteins, in agreement with experiments. Factor H forms large oligomers in >10 µM zinc. In contrast to C3b or Factor H alone, the solubility of the central C3b-Factor H complex was much reduced at 60 µM zinc and even more so at >100 µM zinc. The removal of the C3b-Factor H complex by zinc explains the reduced C3u/C3b inactivation rates by zinc. Zinc-induced precipitation may contribute to the initial development of sub-retinal pigment epithelial deposits in the retina as well as reducing the progression to advanced age-related macular degeneration in higher risk patients.


Asunto(s)
Complemento C3b/metabolismo , Factor H de Complemento/metabolismo , Inflamación/metabolismo , Degeneración Macular/metabolismo , Epitelio Pigmentado de la Retina/metabolismo , Zinc/farmacología , Sitios de Unión , Simulación por Computador , Células Epiteliales/citología , Humanos , Modelos Moleculares , Unión Proteica , Conformación Proteica , Retina/metabolismo , Dispersión de Radiación , Ultracentrifugación , Rayos X , Zinc/química
15.
J Biol Chem ; 288(39): 27737-51, 2013 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-23921391

RESUMEN

The highly sulfated polysaccharides heparin and heparan sulfate (HS) play key roles in the regulation of physiological and pathophysiological processes. Despite its importance, no molecular structures of free HS have been reported up to now. By combining analytical ultracentrifugation, small angle x-ray scattering, and constrained scattering modeling recently used for heparin, we have analyzed the solution structures for eight purified HS fragments dp6-dp24 corresponding to the predominantly unsulfated GlcA-GlcNAc domains of heparan sulfate. Unlike heparin, the sedimentation coefficient s20,w of HS dp6-dp24 showed a small rotor speed dependence, where similar s20,w values of 0.82-1.26 S (absorbance optics) and 1.05-1.34 S (interference optics) were determined. The corresponding x-ray scattering measurements of HS dp6-dp24 gave radii of gyration RG values from 1.03 to 2.82 nm, cross-sectional radii of gyration RXS values from 0.31 to 0.65 nm, and maximum lengths L from 3.0 to 10.0 nm. These data showed that HS has a longer and more bent structure than heparin. Constrained scattering modeling starting from 5,000 to 12,000 conformationally randomized HS structures gave best fit dp6-dp24 molecular structures that were longer and more bent than their equivalents in heparin. Alternative fits were obtained for HS dp18 and dp24, indicating their higher bending and flexibility. We conclude that HS displays bent conformations that are significantly distinct from that for heparin. The difference is attributed to the different predominant monosaccharide sequence and reduced sulfation of HS, indicating that HS may interact differently with proteins compared with heparin.


Asunto(s)
Heparitina Sulfato/química , Cristalización , Glicósidos/química , Heparina/química , Ligandos , Modelos Moleculares , Dispersión de Radiación , Sincrotrones , Ultracentrifugación , Rayos X
16.
Neurotoxicol Teratol ; 102: 107338, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38431065

RESUMEN

BACKGROUND: Prenatal exposure to secondhand (environmental) tobacco smoke (SHS) is associated with adverse neurodevelopmental outcomes, including altered functional activation of cognitive control brain circuitry and increased attention problems in children. Exposure to SHS is more common among Black youth who are also disproportionately exposed to socioeconomic disadvantage and concomitant maternal distress. We examine the combined effects of exposure to prenatal SHS and postnatal maternal distress on the global efficiency (GE) of the brain's cingulo-opercular (CO) and fronto-parietal control (FP) networks in childhood, as well as associated attention problems. METHODS: Thirty-two children of non-smoking mothers followed in a prospective longitudinal birth cohort at the Columbia Center for Children's Environmental Health (CCCEH) completed magnetic resonance imaging (MRI) at ages 7-9 years old. GE scores were extracted from general connectivity data collected while children completed the Simon Spatial Incompatibility functional magnetic resonance imaging (fMRI) task. Prenatal SHS was measured using maternal urinary cotinine from the third trimester; postnatal maternal distress was assessed at child age 5 using the Psychiatric Epidemiology Research Interview (PERI-D). The Child Behavior Checklist (CBCL) measured Attention and Attention Deficit Hyperactivity Disorder (ADHD) problems at ages 7-9. Linear regressions examined the interaction between prenatal SHS and postnatal maternal distress on the GE of the CO or FP networks, as well as associations between exposure-related network alterations and attention problems. All models controlled for age, sex, maternal education at prenatal visit, race/ethnicity, global brain correlation, and mean head motion. RESULTS: The prenatal SHS by postnatal maternal distress interaction term associated with the GE of the CO network (ß = 0.673, Bu = 0.042, t(22) = 2.427, p = .024, D = 1.42, 95% CI [0.006, 0.079], but not the FP network (ß = 0.138, Bu = 0.006, t(22) = 0.434, p = .668, 95% CI [-0.022, 0.033]). Higher GE of the CO network was associated with more attention problems (ß = 0.472, Bu = 43.076, t(23) = 2.780, p = .011, D = 1.74, n = 31, 95% CI [11.024, 75.128], n = 31) and ADHD risk (ß = 0.436, Bu = 21.961, t(29) = 2.567, p = .018, D = 1.81, 95% CI [4.219, 39.703], n = 30). CONCLUSIONS: These preliminary findings suggest that sequential prenatal SHS exposure and postnatal maternal distress could alter the efficiency of the CO network and increase risk for downstream attention problems and ADHD. These findings are consistent with prior studies showing that prenatal SHS exposure is associated with altered function of brain regions that support cognitive control and with ADHD problems. Our model also identifies postnatal maternal distress as a significant moderator of this association. These data highlight the combined neurotoxic effects of exposure to prenatal SHS and postnatal maternal distress. Critically, such exposures are disproportionately distributed among youth from minoritized groups, pointing to potential pathways to known mental health disparities.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Efectos Tardíos de la Exposición Prenatal , Contaminación por Humo de Tabaco , Niño , Femenino , Embarazo , Adolescente , Humanos , Preescolar , Contaminación por Humo de Tabaco/efectos adversos , Estudios Prospectivos , Trastorno por Déficit de Atención con Hiperactividad/etiología , Trastorno por Déficit de Atención con Hiperactividad/psicología , Madres , Cotinina , Efectos Tardíos de la Exposición Prenatal/inducido químicamente
17.
ChemMedChem ; 19(7): e202300548, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38381042

RESUMEN

Several novel chemical series were identified that modulate glucocerebrosidase (GCase). Compounds from these series are active on glucosylceramide, unlike other known GCase modulators. We obtained GCase crystal structures with two compounds that have distinct chemotypes. Positive allosteric modulators bind to a site on GCase and induce conformational changes, but also induce an equilibrium state between monomer and dimer.


Asunto(s)
Enfermedad de Gaucher , Glucosilceramidasa , Humanos , Glucosilceramidasa/química , Glucosilceramidasa/metabolismo , Glucosilceramidas , Hidrólisis , Enfermedad de Gaucher/tratamiento farmacológico
18.
JNCI Cancer Spectr ; 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39051679

RESUMEN

PURPOSE: Neighborhood socioeconomic deprivation has been linked to adverse health outcomes, yet it is unclear if neighborhood-level social determinants of health (SDOH) measures impact overall survival in adolescent and young adult (AYA) cancer patients. METHODS: This study utilized a diverse cohort of AYA cancer patients (N = 10,261) seen at MD Anderson Cancer Center. Zip codes were linked to Area Deprivation Index (ADI) values, a validated neighborhood-level SDOH measure, with higher ADI representing worse SDOH. RESULTS: ADI was significantly worse (p < .05) for Black (61.7) and Hispanic (65.3), compared to White (51.2) patients. Analysis of ADI by cancer type showed significant differences, mainly driven by worse ADI in patients with cervical cancer (62.3) than other cancers. In multivariable models including sex, age at diagnosis, cancer diagnosis, and race/ethnicity, risk of shorter survival for people residing in neighborhoods with the least favorable ADI quartile was greater than those in the most favorable ADI quartile (HR: 1.09, 95% CI: 1.00-1.19, p = .043). CONCLUSION: AYA cancer patients with the worst ADI experienced a nearly 10% increase in risk of dying compared to those with more favorable ADI and this effect was strongest among White AYA survivors. Although the magnitude of the effect of ADI on survival was moderate, the presence of a relationship between neighborhood-level SDOH and survival among patients who received care at a tertiary cancer center suggests ADI is a meaningful predictor of survival. These findings provide intriguing evidence for potential interventions aimed at supporting AYA cancer patients from disadvantaged neighborhoods.

19.
Plants (Basel) ; 13(7)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38611495

RESUMEN

Hamelia patens (Rubiaceae), known as firebush, is a source of bioactive monoterpenoid oxindole alkaloids (MOAs) derived from monoterpenoid indole alkaloids (MIAs). With the aim of understanding the regulation of the biosynthesis of these specialized metabolites, micropropagated plants were elicited with jasmonic acid (JA) and salicylic acid (SA). The MOA production and MIA biosynthetic-related gene expression were evaluated over time. The production of MOAs was increased compared to the control up to 2-fold (41.3 mg g DW-1) at 72 h in JA-elicited plants and 2.5-fold (42.4 mg g DW-1) at 120 h in plants elicited with SA. The increment concurs with the increase in the expression levels of the genes HpaLAMT, HpaTDC, HpaSTR, HpaNPF2.9, HpaTHAS1, and HpaTHAS2. Interestingly, it was found that HpaSGD was downregulated in both treatments after 24 h but in the SA treatment at 120 h only was upregulated to 8-fold compared to the control. In this work, we present the results of MOA production in H. patens and discuss how JA and SA might be regulating the central biosynthetic steps that involve HpaSGD and HpaTHAS genes.

20.
PLoS One ; 19(5): e0304092, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38787900

RESUMEN

AIM: To analyze the relationship between burnout syndrome, cognitive functions, and sBDNF (Serum Brain-derived Neurotrophic Factor) in Mexican nurses. METHOD: A descriptive cross-sectional design was used. This study target staff nurses working in hospitals in Guanajuato, México. Demographic and working condition data were collected via questionnaire. The Maslach Burnout Inventory (MBI) was used to evaluate burnout. A blood sample were collected and processed by ELISA technique to measure sBDNF. Finally, the General Cognitive Assessment (CAB) of the Cognifit© neuropsychological battery was used to evaluated cognitive functions. RESULTS: Findings showed that there are sociodemographic characteristics and working conditions associated with burnout syndrome among nurses. Furthermore, the data demonstrated a significant decrease in sBDNF levels in burnout nurses and a negative correlation between BDNF levels and burnout syndrome. Additionally, these burnout nurse also revealed significant cognitive impairment in reasoning, memory, and attention as well as total scores of CAB. Interestingly, we found a positive correlation between sBDNF levels and the cognitive deficits in burnout nurse. CONCLUSION: Reduced BDNF levels could be a biological indicator or part of the pathological process of burnout, which could affect cognitive abilities. Reduced cognitive function in nurses has relevant implications and emphasizes the need for specialized preventive strategies because nurses make clinical decisions concerning their patients, whose situations are constantly changing.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo , Agotamiento Profesional , Cognición , Humanos , Factor Neurotrófico Derivado del Encéfalo/sangre , Agotamiento Profesional/epidemiología , Agotamiento Profesional/psicología , México/epidemiología , Femenino , Adulto , Cognición/fisiología , Masculino , Estudios Transversales , Personal de Enfermería en Hospital/psicología , Personal de Enfermería en Hospital/estadística & datos numéricos , Persona de Mediana Edad , Enfermeras y Enfermeros/psicología , Encuestas y Cuestionarios , Adulto Joven
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