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1.
J Infect Dis ; 229(3): 648-659, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-37925630

RESUMEN

BACKGROUND: Data on the effectiveness of BA.4/5 bivalent vaccine stratified by age and prior infection are lacking. METHODS: This test-negative study used data from individuals ≥5 years of age testing for SARS-CoV-2 with symptoms (15 September 2022 to 31 January 2023) at a large national retail pharmacy chain. The exposure was receipt of 2-4 wild-type doses and a BNT162b2 BA.4/5 bivalent vaccine (>2 months since last wild-type dose). The outcome was a positive SARS-CoV-2 test. Absolute (vs unvaccinated) and relative (vs 2-4 wild-type doses) vaccine effectiveness (VE) were calculated as (1 - adjusted odds ratio from logistic regression) × 100. VE was stratified by age and self-reported prior infection. RESULTS: Overall, 307 885 SARS-CoV-2 tests were included (7916 aged 5-11, 16 329 aged 12-17, and 283 640 aged ≥18 years). SARS-CoV-2 positivity was 39%; 21% were unvaccinated, 70% received 2-4 wild-type doses with no bivalent vaccine, and 9% received a BNT162b2 BA.4/5 bivalent dose. At a median of 1-2 months after BNT162b2 BA.4/5 bivalent vaccination, depending on age group, absolute VE was 22%-60% and was significantly higher among those reporting prior infection (range, 55%-79%) than not (range, no protection to 50%). Relative VE was 31%-64%. CONCLUSIONS: BNT162b2 BA.4/5 bivalent showed early additional protection against Omicron-related symptomatic COVID-19, with hybrid immunity offering greater protection.


Asunto(s)
COVID-19 , Farmacia , Humanos , Adolescente , Adulto , Preescolar , Vacuna BNT162 , Vacunas de ARNm , COVID-19/epidemiología , COVID-19/prevención & control , SARS-CoV-2/genética , Vacunas Combinadas
2.
Artículo en Inglés | MEDLINE | ID: mdl-38691660

RESUMEN

SNPs in the FAM13A locus are amongst the most commonly reported risk alleles associated with chronic obstructive pulmonary disease (COPD) and other respiratory diseases, however the physiological role of FAM13A is unclear. In humans, two major protein isoforms are expressed at the FAM13A locus: 'long' and 'short', but their functions remain unknown, partly due to a lack of isoform conservation in mice. We performed in-depth characterisation of organotypic primary human airway epithelial cell subsets and show that multiciliated cells predominantly express the FAM13A long isoform containing a putative N-terminal Rho GTPase activating protein (RhoGAP) domain. Using purified proteins, we directly demonstrate RhoGAP activity of this domain. In Xenopus laevis, which conserve the long isoform, Fam13a-deficiency impaired cilia-dependent embryo motility. In human primary epithelial cells, long isoform deficiency did not affect multiciliogenesis but reduced cilia co-ordination in mucociliary transport assays. This is the first demonstration that FAM13A isoforms are differentially expressed within the airway epithelium, with implications for the assessment and interpretation of SNP effects on FAM13A expression levels. We also show that the long FAM13A isoform co-ordinates cilia-driven movement, suggesting that FAM13A risk alleles may affect susceptibility to respiratory diseases through deficiencies in mucociliary clearance. This article is open access and distributed under the terms of the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/).

3.
Plant Cell Rep ; 43(2): 49, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38302760

RESUMEN

KEY MESSAGE: Paenibacillus lentimorbus reprograms auxin signaling and metabolic pathways for modulating root system architecture to mitigate nutrient deficiency in maize crops. The arable land across the world is having deficiency and disproportionate nutrients, limiting crop productivity. In this study, the potential of plant growth-promoting rhizobacteria (PGPR) viz., Pseudomonas putida, Paenibacillus lentimorbus, and their consortium was explored for growth promotion in maize (Zea mays) under nutrient-deficient conditions. PGPR inoculation improved the overall health of plants under nutrient-deficient conditions. The PGPR inoculation significantly improved the root system architecture and also induced changes in root cortical aerenchyma. Based on plant growth and physiological parameters inoculation with P. lentimorbus performed better as compared to P. putida, consortium, and uninoculated control. Furthermore, expression of auxin signaling (rum1, rul1, lrp1, rtcs, rtcl) and root hair development (rth)-related genes modulated the root development process to improve nutrient acquisition and tolerance to nutrient-deficient conditions in P. lentimorbus inoculated maize plants. Further, GC-MS analysis indicated the involvement of metabolites including carbohydrates and organic acids due to the interaction between maize roots and P. lentimorbus under nutrient-deficient conditions. These findings affirm that P. lentimorbus enhance overall plant growth by modulating the root system of maize to provide better tolerance to nutrient-deficient condition.


Asunto(s)
Bacillus , Paenibacillus , Zea mays , Zea mays/genética , Redes y Vías Metabólicas , Nutrientes , Ácidos Indolacéticos/metabolismo , Raíces de Plantas/metabolismo
4.
BMC Womens Health ; 24(1): 119, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38355501

RESUMEN

BACKGROUND: Birth preparedness and complication readiness (BPCR) is an essential component of safe motherhood programs. This study aims to systematically identify and synthesize available evidence on birth preparedness and complication readiness among pregnant and recently delivered women in India. METHODS: The study followed PRISMA guidelines and used databases such as PubMed, Cochrane Library, and ProQuest. Joanna Briggs Institute [JBI] Tool was used for critical appraisal of studies. The meta-analysis was conducted using Comprehensive Meta-Analysis [CMA] tool and R studio software. Statistical heterogeneity was evaluated using visual inspection of the forest plot, Cochran's Q test, and the I2 statistic results. Funnel plot and Egger's tests were applied to explore the possibility of the publication bias in the studies [PROSPERO: CRD42023396109]. RESULT: Thirty-five cross-sectional studies reported knowledge on one or more components of birth preparedness [BP], whilst knowledge on complication readiness [CR] or danger signs was reported in 34 included studies. Utilizing the random effect model, the pooled result showed that only about half of the women [49%; 95% CI: 44%, 53%] were aware on BPCR components. This result ranged between 15% [95% CI: 12%, 19%] to 79% [95% CI: 72%, 84%] in Maharashtra and Karnataka respectively [I2 = 94%, p = < 0.01]. High heterogeneity [> 90%] is observed across all components [p < 0.01]. The result of subgroup analysis indicated no significant difference in the proportion on BPCR among pregnant women [50%; 95% CI: 45%, 55%] and recently delivered women [54%; 95% CI: 46%, 62%]. However, the southern region of India indicates relatively better [56%; 95% CI: 45%, 67%] prevalence. CONCLUSION: Our study highlights the low prevalence of BPCR in India and the factors associated with it. Scaling up cost-effective interventions like BPCR that have a positive overall effect is necessary. Authors strongly suggests that birth preparedness and complication readiness should be given utmost importance to reduce maternal morbidity and mortality to achieve the Sustainable Development Goals. Consideration should be given to fortifying existing resources, such as frontline workers and primary healthcare, as a strategic approach to augmenting the effectiveness of awareness initiatives.


Asunto(s)
Complicaciones del Embarazo , Atención Prenatal , Femenino , Humanos , Embarazo , Estudios Transversales , Parto Obstétrico , Conocimientos, Actitudes y Práctica en Salud , India , Complicaciones del Embarazo/epidemiología
5.
Mol Psychiatry ; 27(2): 819-830, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34112971

RESUMEN

Copy Number Variation (CNV) at the 1q21.1 locus is associated with a range of neurodevelopmental and psychiatric disorders in humans, including abnormalities in head size and motor deficits. Yet, the functional consequences of these CNVs (both deletion and duplication) on neuronal development remain unknown. To determine the impact of CNV at the 1q21.1 locus on neuronal development, we generated induced pluripotent stem cells from individuals harbouring 1q21.1 deletion or duplication and differentiated them into functional cortical neurons. We show that neurons with 1q21.1 deletion or duplication display reciprocal phenotype with respect to proliferation, differentiation potential, neuronal maturation, synaptic density and functional activity. Deletion of the 1q21.1 locus was also associated with an increased expression of lower cortical layer markers. This difference was conserved in the mouse model of 1q21.1 deletion, which displayed altered corticogenesis. Importantly, we show that neurons with 1q21.1 deletion and duplication are associated with differential expression of calcium channels and demonstrate that physiological deficits in neurons with 1q21.1 deletion or duplication can be pharmacologically modulated by targeting Ca2+ channel activity. These findings provide biological insight into the neuropathological mechanism underlying 1q21.1 associated brain disorder and indicate a potential target for therapeutic interventions.


Asunto(s)
Variaciones en el Número de Copia de ADN , Células Madre Pluripotentes Inducidas , Anomalías Múltiples , Animales , Deleción Cromosómica , Cromosomas Humanos Par 1 , Variaciones en el Número de Copia de ADN/genética , Humanos , Megalencefalia , Ratones , Neuronas , Fenotipo
6.
J Eur Acad Dermatol Venereol ; 37(12): 2601-2607, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37620285

RESUMEN

BACKGROUND: Kligman's trio (KT), combining hydroquinone, retinoic acid and corticosteroid, is considered as the gold standard treatment of melasma. Its efficacy has never been matched before, but it is tempered by frequent adverse effects. OBJECTIVE: To assess the efficacy and tolerance of a New Trio (NT) combination with isobutylamido-thiazolyl-resorcinol, retinoic acid and cortosteroid compared to KT. METHODS: We conducted a 24-week monocentric trial, randomized, double-blind, controlled versus KT, with 40 melasma patients. NT and KT were applied for 12 weeks and associated with the same sunscreen applied for 24 weeks. The primary endpoint was the modified Melasma Area Severity Index (mMASI) at 12 weeks. Patient quality of life was investigated using MelasQoL. RESULTS: After 12 weeks, KT and NT groups both demonstrated a significant improvement in mMASI, respectively -2.84 (SE 0.69, p < 0.0002) and -4.33 (SE 0.71, p < 0.0001). The mean difference between the two groups was -1.49 (IC 95% -3.52 to 0.54, p = 0.14). MelasQoL improvement was -6.66 (SE 3.29, p = 0.0515) with KT and -12.57 (SE 3.29, p = 0.0006) with NT. CONCLUSION: The NT combination appears to be an effective treatment option for treating melasma and could be considered as a well-tolerated alternative to KT.


Asunto(s)
Melanosis , Calidad de Vida , Humanos , Estudios Prospectivos , Tretinoina/efectos adversos , Resultado del Tratamiento , Emolientes , Melanosis/tratamiento farmacológico , Hidroquinonas/efectos adversos
7.
Int J Biometeorol ; 66(8): 1505-1513, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35554684

RESUMEN

Many populations experience high seasonal temperatures. Pregnant women are considered vulnerable to extreme heat because ambient heat exposure has been linked to pregnancy complications including preterm birth and low birthweight. The physiological mechanisms that underpin these associations are poorly understood. We reviewed the existing research evidence to clarify the mechanisms that lead to adverse pregnancy outcomes in order to inform public health actions. A multi-disciplinary expert group met to review the existing evidence base and formulate a consensus regarding the physiological mechanisms that mediate the effect of high ambient temperature on pregnancy. A literature search was conducted in advance of the meeting to identify existing hypotheses and develop a series of questions and themes for discussion. Numerous hypotheses have been generated based on animal models and limited observational studies. There is growing evidence that pregnant women are able to appropriately thermoregulate; however, when exposed to extreme heat, there are a number of processes that may occur which could harm the mother or fetus including a reduction in placental blood flow, dehydration, and an inflammatory response that may trigger preterm birth. There is a lack of substantial evidence regarding the processes that cause heat exposure to harm pregnant women. Research is urgently needed to identify what causes the adverse outcomes in pregnancy related to high ambient temperatures so that the impact of climate change on pregnant women can be mitigated.


Asunto(s)
Nacimiento Prematuro , Femenino , Procesos de Grupo , Calor , Humanos , Recién Nacido , Placenta , Embarazo
8.
Stem Cells ; 38(5): 683-697, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32012382

RESUMEN

The role of miRNAs in determining human neural stem cell (NSC) fate remains elusive despite their high expression in the developing nervous system. In this study, we investigate the role of miR-137, a brain-enriched miRNA, in determining the fate of human induced pluripotent stem cells-derived NSCs (hiNSCs). We show that ectopic expression of miR-137 in hiNSCs reduces proliferation and accelerates neuronal differentiation and migration. TargetScan and MicroT-CDS predict myocyte enhancer factor-2A (MEF2A), a transcription factor that regulates peroxisome proliferator-activated receptor-gamma coactivator (PGC1α) transcription, as a target of miR-137. Using a reporter assay, we validate MEF2A as a downstream target of miR-137. Our results indicate that reduced levels of MEF2A reduce the transcription of PGC1α, which in turn impacts mitochondrial dynamics. Notably, miR-137 accelerates mitochondrial biogenesis in a PGC1α independent manner by upregulating nuclear factor erythroid 2 (NFE2)-related factor 2 (NRF2) and transcription factor A of mitochondria (TFAM). In addition, miR-137 modulates mitochondrial dynamics by inducing mitochondrial fusion and fission events, resulting in increased mitochondrial content and activation of oxidative phosphorylation (OXPHOS) and oxygen consumption rate. Pluripotency transcription factors OCT4 and SOX2 are known to have binding sites in the promoter region of miR-137 gene. Ectopic expression of miR-137 elevates the expression levels of OCT4 and SOX2 in hiNSCs which establishes a feed-forward self-regulatory loop between miR-137 and OCT4/SOX2. Our study provides novel molecular insights into NSC fate determination by miR-137.


Asunto(s)
MicroARNs/metabolismo , Dinámicas Mitocondriales/fisiología , Células-Madre Neurales/metabolismo , Diferenciación Celular/fisiología , Regulación hacia Abajo , Humanos , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/metabolismo , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/metabolismo , MicroARNs/genética , Células-Madre Neurales/citología , Factor 3 de Transcripción de Unión a Octámeros/genética , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Biogénesis de Organelos , Factores de Transcripción SOXB1/genética , Factores de Transcripción SOXB1/metabolismo
9.
J Nutr ; 151(9): 2622-2635, 2021 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-34113994

RESUMEN

BACKGROUND: Low vitamin D status is a global public health issue that vitamin D food fortification and biofortification may help to alleviate. OBJECTIVES: We investigated the effect of vitamin D food fortification and biofortification on circulating 25-hydroxyvitamin D (25(OH)D) concentrations. We expanded the scope of earlier reviews to include adults and children, to evaluate effects by vitamin D vitamer, and investigate linear and nonlinear dose-response relations. METHODS: We conducted a systematic review and meta-analysis. We searched CINAHL, MEDLINE, PubMed, Embase, the Cochrane Library, and gray and unpublished literature sites for randomized controlled trials, including people of all ages, with the criteria: absence of illness affecting vitamin D absorption, duration ≥4 wk, equivalent placebo food control, dose quantification, dose ≥5 µg/d, baseline and endpoint or absolute change in 25(OH)D concentrations reported, random allocation, and participant blinding. Quality was assessed using the Jadad Scale. RESULTS: Data from 34 publications (2398 adults: 1345 intervention, 1053 controls; 1532 children: 970 intervention, 562 controls) were included. Random-effects meta-analysis of all studies combined (mean dose 16.2 µg/d) indicated a pooled treatment effect of 21.2 nmol/L (95% CI: 16.2, 26.2), with a greater effect for studies using cholecalciferol than ergocalciferol. Heterogeneity was high (I2  > 75%). Metaregression analyses for all studies combined suggested positive effect differences for baseline circulating 25(OH)D concentrations <50 nmol/L, dose ≥10 µg/d and a negative effect difference when the intervention arm included a calcium dose ≥500 mg/d greater than the control arm. Dose-response rates were found to be nonlinear (Wald test for nonlinearity P < 0.001). For all studies combined, a threshold occurred at ∼26 nmol/L for a dose of ∼21 µg/d. CONCLUSIONS: These results support use of vitamin D food fortification to improve circulating 25(OH)D circulations in populations. This work was registered with PROSPERO as CRD42020145497.


Asunto(s)
Biofortificación , Deficiencia de Vitamina D , Adulto , Niño , Suplementos Dietéticos , Alimentos Fortificados , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Vitamina D/análogos & derivados , Deficiencia de Vitamina D/tratamiento farmacológico , Deficiencia de Vitamina D/prevención & control
10.
Int J Behav Med ; 28(6): 820-826, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33649888

RESUMEN

BACKGROUND: The strategies patients use to cope with chronic pain are key determinants of pain-related treatment outcomes and are often targeted in psychosocial interventions for chronic pain. However, improvements in coping often fade after intervention completion. Here, we test whether previously reported improvements in coping following two novel mind-body and activity interventions are maintained 3 months after completion. METHODS: Eighty-two patients with heterogeneous chronic pain were randomized to two identical mind-body and activity interventions, one with the addition of a Fitbit device (GetActive-Fitbit) and one without it (GetActive; n = 41 each). Participants completed measures of pain-catastrophizing, kinesiophobia, mindfulness, adaptive coping, and pain-resilience at baseline, post-intervention, and at 3-month follow-up. RESULTS: At follow-up, participants in both groups exhibited sustained improvements in all five coping measures compared to baseline (significant in both groups for all measures except for p = .05 in kinesiophobia in GetActive and p = .07 in pain resilience in GetActive-Fitbit). CONCLUSIONS: Overall, GetActive and GetcActive-Fitbit are promising interventions to sustainably improve coping with chronic pain. TRIAL REGISTRATION: This trial is registered under ClinicalTrials.gov identifier NCT03412916.


Asunto(s)
Dolor Crónico , Atención Plena , Adaptación Psicológica , Catastrofización , Dolor Crónico/terapia , Humanos , Resultado del Tratamiento
11.
J Biol Chem ; 294(34): 12610-12621, 2019 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-31315929

RESUMEN

Microtubule-associated protein 1 light chain 3 α (LC3)/GABA type A receptor-associated protein (GABARAP) comprises a family of ubiquitin-like proteins involved in (macro)autophagy, an important intracellular degradation pathway that delivers cytoplasmic material to lysosomes via double-membrane vesicles called autophagosomes. The only currently known cellular molecules covalently modified by LC3/GABARAP are membrane phospholipids such as phosphatidylethanolamine in the autophagosome membrane. Autophagy-related 4 cysteine peptidase (ATG4) proteases process inactive pro-LC3/GABARAP before lipidation, and the same proteases can also deconjugate LC3/GABARAP from lipids. To determine whether LC3/GABARAP has other molecular targets, here we generated a pre-processed LC3B mutant (Q116P) that is resistant to ATG4-mediated deconjugation. Upon expression in human cells and when assessed by immunoblotting under reducing and denaturing conditions, deconjugation-resistant LC3B accumulated in multiple forms and at much higher molecular weights than free LC3B. We observed a similar accumulation when pre-processed versions of all mammalian LC3/GABARAP isoforms were expressed in ATG4-deficient cell lines, suggesting that LC3/GABARAP can attach also to other larger molecules. We identified ATG3, the E2-like enzyme involved in LC3/GABARAP lipidation, as one target of conjugation with multiple copies of LC3/GABARAP. We show that LC3B-ATG3 conjugates are distinct from the LC3B-ATG3 thioester intermediate formed before lipidation, and we biochemically demonstrate that ATG4B can cleave LC3B-ATG3 conjugates. Finally, we determined ATG3 residue Lys-243 as an LC3B modification site. Overall, we provide the first cellular evidence that mammalian LC3/GABARAP post-translationally modifies proteins akin to ubiquitination ("LC3ylation"), with ATG4 proteases acting like deubiquitinating enzymes to counteract this modification ("deLC3ylation").


Asunto(s)
Proteínas Reguladoras de la Apoptosis/metabolismo , Proteínas Relacionadas con la Autofagia/metabolismo , Autofagia , Cisteína Endopeptidasas/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Ubiquitinas/metabolismo , Células HeLa , Humanos , Peso Molecular , Mutación/genética , Especificidad por Sustrato
12.
Int J Mol Sci ; 22(1)2020 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-33396714

RESUMEN

One of the major challenges in the treatment of cancer are differential responses of patients to existing standard of care anti-cancer drugs. These differential responses may, in part, be due to a diverse range of genomic, epigenomic, proteomic, and metabolic alterations among individuals suffering from the same type of cancer. Precision medicine is an emerging approach in cancer therapeutics that takes into account specific molecular alterations, environmental factors as well as lifestyle of individual patients. This approach allows clinicians and researchers to select or predict treatments that would most likely benefit the patient based on their individual tumor characteristics. One class of precision medicine tools are predictive, in vitro drug-response assays designed to test the sensitivity of patient tumor cells to existing or novel therapies. These assays have the potential to rapidly identify the most effective treatments for cancer patients and thus hold great promise in the field of precision medicine. In this review, we have highlighted several drug-response assays developed in ovarian cancer and discussed the current challenges and future prospects of these assays in the clinical management of this disease.


Asunto(s)
Antineoplásicos/farmacología , Evaluación Preclínica de Medicamentos/métodos , Resistencia a Antineoplásicos/efectos de los fármacos , Neoplasias Ováricas/diagnóstico , Medicina de Precisión , Animales , Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Técnicas de Cultivo de Célula , Ensayos Clínicos como Asunto , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/etiología , Guías de Práctica Clínica como Asunto , Medicina de Precisión/métodos , Esferoides Celulares , Técnicas de Cultivo de Tejidos , Resultado del Tratamiento
13.
Bioinformatics ; 33(10): 1488-1496, 2017 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-28073762

RESUMEN

MOTIVATION: Drug intercalation is an important strategy for DNA inhibition which is often employed in cancer chemotherapy. Despite its high significance, the field is characterized by limited success in identification of novel intercalator molecules and lack of automated and dedicated drug-DNA intercalation methodology. RESULTS: We report here a novel intercalation methodology (christened ' Intercalate' ) for predicting both the structures and energetics of DNA-intercalator complexes, covering the processes of DNA unwinding and (non-covalent) binding. Given a DNA sequence and intercalation site information, Intercalate generates the 3D structure of DNA, creates the intercalation site, performs docking at the intercalation site and evaluates DNA-intercalator binding energy in an automated way. The structures and energetics of the DNA-intercalator complexes produced by Intercalate methodology are seen to be in good agreement with experiment. The dedicated attempt made in developing a drug-DNA intercalation methodology (compatible with its mechanism) with high accuracy should prove useful in the discovery of potential intercalators for their use as anticancers, antibacterials or antivirals. AVAILABILITY AND IMPLEMENTATION: http://www.scfbio-iitd.res.in/intercalate/. CONTACT: anjali@scfbio-iitd.res.in or bjayaram@chemistry.iitd.ac.in. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
ADN/química , Sustancias Intercalantes/química , Simulación de Dinámica Molecular , Programas Informáticos , Termodinámica , Antibacterianos/química , Antineoplásicos/química , Antivirales/química , Sitios de Unión , Simulación del Acoplamiento Molecular , Conformación de Ácido Nucleico
14.
Exp Eye Res ; 173: 129-137, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29753729

RESUMEN

Emerging therapies have begun to evaluate the abilities of Müller glial cells (MGCs) to protect and/or regenerate neurons following retina injury. The migration of donor cells is central to many reparative strategies, where cells must achieve appropriate positioning to facilitate localized repair. Although chemical cues have been implicated in the MGC migratory responses of numerous retinopathies, MGC-based therapies have yet to explore the extent to which external biochemical stimuli can direct MGC behavior. The current study uses a microfluidics-based assay to evaluate the migration of cultured rMC-1 cells (as model MGC) in response to quantitatively-controlled microenvironments of signaling factors implicated in retinal regeneration: basic Fibroblast Growth factor (bFGF or FGF2); Fibroblast Growth factor 8 (FGF8); Vascular Endothelial Growth Factor (VEGF); and Epidermal Growth Factor (EGF). Findings indicate that rMC-1 cells exhibited minimal motility in response to FGF2, FGF8 and VEGF, but highly-directional migration in response to EGF. Further, the responses were blocked by inhibitors of EGF-R and of the MAPK signaling pathway. Significantly, microfluidics data demonstrate that changes in the EGF gradient (i.e. change in EGF concentration over distance) resulted in the directional chemotactic migration of the cells. By contrast, small increases in EGF concentration, alone, resulted in non-directional cell motility, or chemokinesis. This microfluidics-enhanced approach, incorporating the ability both to modulate and asses the responses of motile donor cells to a range of potential chemotactic stimuli, can be applied to potential donor cell populations obtained directly from human specimens, and readily expanded to incorporate drug-eluting biomaterials and combinations of desired ligands.


Asunto(s)
Quimiotaxis/fisiología , Células Ependimogliales/fisiología , Animales , Proliferación Celular/fisiología , Células Cultivadas , Microambiente Celular , Células Ependimogliales/efectos de los fármacos , Factor de Crecimiento Epidérmico/farmacología , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/metabolismo , Clorhidrato de Erlotinib/farmacología , Factor 2 de Crecimiento de Fibroblastos/farmacología , Factor 8 de Crecimiento de Fibroblastos/farmacología , Proteína Ácida Fibrilar de la Glía/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/fisiología , Técnicas Analíticas Microfluídicas , Nestina/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , ARN Mensajero/genética , Ratas , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores de Factores de Crecimiento/genética , Factor A de Crecimiento Endotelial Vascular/farmacología
15.
Biol Lett ; 13(3)2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28250208

RESUMEN

Mutation is the ultimate source of the genetic variation-including variation for mutation rate itself-that fuels evolution. Natural selection can raise or lower the genomic mutation rate of a population by changing the frequencies of mutation rate modifier alleles associated with beneficial and deleterious mutations. Existing theory and observations suggest that where selection is minimized, rapid systematic evolution of mutation rate either up or down is unlikely. Here, we report systematic evolution of higher and lower mutation rates in replicate hypermutable Escherichia coli populations experimentally propagated at very small effective size-a circumstance under which selection is greatly reduced. Several populations went extinct during this experiment, and these populations tended to evolve elevated mutation rates. In contrast, populations that survived to the end of the experiment tended to evolve decreased mutation rates. We discuss the relevance of our results to current ideas about the evolution, maintenance and consequences of high mutation rates.


Asunto(s)
Escherichia coli/genética , Evolución Molecular , Antibacterianos/farmacología , Farmacorresistencia Microbiana/genética , Escherichia coli/efectos de los fármacos , Aptitud Genética , Tasa de Mutación , Ácido Nalidíxico/farmacología , Selección Genética , Estreptomicina/farmacología
16.
Bioinformatics ; 31(7): 999-1006, 2015 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-25431331

RESUMEN

MOTIVATION: Recent developments of statistical techniques to infer direct evolutionary couplings between residue pairs have rendered covariation-based contact prediction a viable means for accurate 3D modelling of proteins, with no information other than the sequence required. To extend the usefulness of contact prediction, we have designed a new meta-predictor (MetaPSICOV) which combines three distinct approaches for inferring covariation signals from multiple sequence alignments, considers a broad range of other sequence-derived features and, uniquely, a range of metrics which describe both the local and global quality of the input multiple sequence alignment. Finally, we use a two-stage predictor, where the second stage filters the output of the first stage. This two-stage predictor is additionally evaluated on its ability to accurately predict the long range network of hydrogen bonds, including correctly assigning the donor and acceptor residues. RESULTS: Using the original PSICOV benchmark set of 150 protein families, MetaPSICOV achieves a mean precision of 0.54 for top-L predicted long range contacts-around 60% higher than PSICOV, and around 40% better than CCMpred. In de novo protein structure prediction using FRAGFOLD, MetaPSICOV is able to improve the TM-scores of models by a median of 0.05 compared with PSICOV. Lastly, for predicting long range hydrogen bonding, MetaPSICOV-HB achieves a precision of 0.69 for the top-L/10 hydrogen bonds compared with just 0.26 for the baseline MetaPSICOV. AVAILABILITY AND IMPLEMENTATION: MetaPSICOV is available as a freely available web server at http://bioinf.cs.ucl.ac.uk/MetaPSICOV. Raw data (predicted contact lists and 3D models) and source code can be downloaded from http://bioinf.cs.ucl.ac.uk/downloads/MetaPSICOV. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Algoritmos , Biología Computacional/métodos , Proteínas/química , Alineación de Secuencia/métodos , Análisis de Secuencia de Proteína/métodos , Programas Informáticos , Bases de Datos de Proteínas , Humanos , Enlace de Hidrógeno , Pliegue de Proteína
17.
J Nerv Ment Dis ; 204(11): 806-811, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27105457

RESUMEN

Suicide attempters differ in the degree of planning for their suicide attempts. The purpose of this study was to identify differences between individuals who make planned (≥3 hours of planning) and unplanned (<3 hours of planning) suicide attempts. Depressed suicide attempters (n = 110) were compared based on degree of planning of their most recent suicide attempt on demographic and clinical variables. Participants who made planned suicide attempts were more likely to have family history of completed suicide, more severe and frequent suicidal ideation, greater trait impulsivity, and greater suicidal intent and more severe medical consequences for both their most recent and most serious suicide attempts. These results suggest clear clinical differences based on the degree of suicide attempt planning. Severe suicidal ideation, high suicide intent, family history of suicide completion, and high levels of motor impulsivity contribute to a phenotype that is at greater risk of planned, highly lethal suicide attempts.


Asunto(s)
Trastorno Depresivo Mayor/psicología , Conducta Impulsiva , Ideación Suicida , Intento de Suicidio/psicología , Suicidio/psicología , Adulto , Trastorno Depresivo Mayor/terapia , Femenino , Humanos , Masculino , Intento de Suicidio/prevención & control , Adulto Joven , Prevención del Suicidio
18.
Photochem Photobiol Sci ; 14(7): 1329-36, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26066468

RESUMEN

Single component fluorescent organic polymeric nanoparticles (NPs) have been synthesized based on a star shaped 4-arm PEG containing coumarin chromophore for the concomitant employment of photodynamic therapy (PDT) and chemotherapy synergistically to wipe out tumour cells with a high efficiency. Polymeric NPs are emerging as the most promising nanoparticulates in the area of drug delivery systems due to their ability to overcome the disadvantages like premature and imprecise control over the drug release, lack of loading capacity etc. Among polymeric NPs, star shaped branched polymers have attracted great attention mainly due to their multiple functionalization properties. Hence, herein we have made use of a multi-arm PEG, functionalized with a targeting unit biotin and a coumarin fluorophore for site-specific and image guided synergic treatment of cancer cells. The anticancer drug chlorambucil is released by the coumarin chromophore in a photocontrolled manner. In addition to that, coumarin also generated singlet oxygen upon irradiation with UV/vis light (≥365 nm) with a moderate quantum yield of ∼0.37. In vitro application of thus prepared organic polymeric nanoparticles (PEG-Bio-Cou-Cbl) in the HeLa cell line shows a reduction of cell viability by up to ∼5% in the case of a combined treatment of PDT and chemotherapy whereas analogous organic polymeric NPs without the chemotherapeutic drug (PEG-Bio-Cou) result in ∼49% cell viability by means of PDT process only.


Asunto(s)
Cumarinas/química , Sistemas de Liberación de Medicamentos , Nanopartículas/química , Fotoquimioterapia , Polietilenglicoles/química , Antineoplásicos/química , Clorambucilo/química , Células HeLa , Humanos , Estructura Molecular
19.
Indian Pediatr ; 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38910366

RESUMEN

OBJECTIVE: To estimate the change in serum hepcidin levels and its correlation with change in hemoglobin (Hb) level during the initial two weeks of oral iron therapy in children with iron deficiency anemia (IDA). METHODS: A prospective observational study was carried out in children aged 2-12 years with IDA. Children with severe anemia (Hb < 7 g/ dL), those with fever, infections, history of oral iron intake or blood transfusion within the preceding three months, or intolerant to oral iron were excluded. Serum hepcidin-25 was assessed using ELISA-based kits on day 0 (pre-therapy), after 24 hours and 14 days of starting oral iron therapy. RESULTS: Out of 78 children who were screened for inclusion, we included 64 children with IDA with a mean (SD) hemoglobin of 8.81 (1.22) g/dL. The baseline mean (SD) serum hepcidin-25 levels [7.81 (4.88) ng/mL] increased significantly to 8.38 (4.96) at 24 hours and 9.51 (5.2) on day 14 of oral iron therapy (P < 0.001). 63 children showed a good response to oral iron therapy. No significant correlation was observed between baseline hepcidin levels with change in hemoglobin on day 1 (r = -0.10, P = 0.40) or day 14 (r = -0.10, P = 0.43) of therapy. CONCLUSION: Serum hepcidin levels rise significantly as early as 24 hours after starting oral iron therapy and should be explored to assess response to oral iron therapy in children with anemia.

20.
Plant Physiol Biochem ; 206: 108273, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38103339

RESUMEN

Root system architecture, encompassing lateral roots and root hairs, plays a vital in overall plant growth and stress tolerance. Reactive oxygen species (ROS) and plant hormones intricately regulate root growth and development, serving as signaling molecules that govern processes such as cell proliferation and differentiation. Manipulating the interplay between ROS and hormones has the potential to enhance nutrient absorption, stress tolerance, and agricultural productivity. In this review, we delve into how studying these processes provides insights into how plants respond to environmental changes and optimize growth patterns to better control cellular processes and stress responses in crops. We discuss various factors and complex signaling networks that may exist among ROS and phytohormones during root development. Additionally, the review highlights possible role of reactive nitrogen species (RNS) in ROS-phytohormone interactions and in shaping root system architecture according to environmental cues.


Asunto(s)
Señales (Psicología) , Reguladores del Crecimiento de las Plantas , Reguladores del Crecimiento de las Plantas/farmacología , Especies Reactivas de Oxígeno , Productos Agrícolas , Raíces de Plantas
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