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1.
Eur J Neurosci ; 57(1): 163-177, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36251568

RESUMEN

Freezing of gait (FOG) is a debilitating motor symptom of Parkinson's disease (PD). Although PD dopaminergic medication (L-DOPA) seems to generally reduce FOG severity, its effect on neural mechanisms of FOG remains to be determined. The purpose of this study was to quantify the effect of L-DOPA on brain resting-state functional connectivity in individuals with FOG. Functional magnetic resonance imaging was acquired at rest in 30 individuals living with PD (15 freezers) in the ON- and OFF- medication state. A seed-to-voxel analysis was performed with seeds in the bilateral basal ganglia nuclei, the thalamus and the mesencephalic locomotor region. In freezers, medication-state contrasts revealed numerous changes in resting-state functional connectivity, not modulated by L-DOPA in non-freezers. In freezers, L-DOPA increased the functional connectivity between the seeds and regions including the posterior parietal, the posterior cingulate, the motor and the medial prefrontal cortices. Comparisons with non-freezers revealed that L-DOPA generally normalizes brain functional connectivity to non-freezers levels but can also increase functional connectivity, possibly compensating for dysfunctional networks in freezers. Our findings suggest that L-DOPA could contribute to a better sensorimotor, attentional, response inhibition and limbic processing to prevent FOG when triggers are encountered but could also contribute to FOG by interfering with the processing capacity of the striatum. This study shows that levodopa taken to control PD symptoms induces changes in functional connectivity at rest, in freezers only. Increases (green) in functional connectivity of GPe, GPi, putamen and thalamus with cognitive, sensorimotor and limbic cortical regions of the Interference model (blue) was observed. Our results suggest that levodopa can normalize connections similar to non-freezers or increases connectivity to compensate for dysfunctional networks.


Asunto(s)
Trastornos Neurológicos de la Marcha , Enfermedad de Parkinson , Humanos , Levodopa/farmacología , Levodopa/uso terapéutico , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/patología , Trastornos Neurológicos de la Marcha/tratamiento farmacológico , Trastornos Neurológicos de la Marcha/etiología , Encéfalo , Marcha , Imagen por Resonancia Magnética
2.
Dev Dyn ; 251(11): 1848-1861, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35766167

RESUMEN

BACKGROUND: Temporary pools are variable environments with seasonal drought/flood phases. Annual killifish have adapted to life in temporary pools by producing embryos that undergo diapause to traverse the dry phase. To fill existing knowledge gaps about embryo diapause regulation and evolution in annual killifishes, we test the effect of maternal age, incubation temperature, and incubation medium on diapause induction and length in Millerichthys robustus, the only North American fish species that has evolved an annual life history. RESULTS: All embryos at extreme temperatures follow a defined developmental pathway: skipping diapause at 30°C, and entering diapause at 18°C, both regardless of maternal age, and incubation medium. However, maternal age, and incubation medium influenced whether diapause is entered, and time arrested in diapause for embryos incubated at 25°C. At 25°C, five-week-old, and 52-week-old females produced more embryos that entered diapause than 26-week-old females. Also, embryos incubated in aqueous medium skipped diapause more frequently at this intermediate temperature. CONCLUSIONS: Millerichthys developmental dynamics associated with maternal age under intermediate range of temperatures are likely adapted to the particular patterns of flood/drought in North American temporary pools. Millerichthys also exhibits developmental patterns largely comparable with other annual fishes, probably due to common seasonal patterns in temporary pools.


Asunto(s)
Ciprinodontiformes , Diapausa , Fundulidae , Animales , Femenino , Edad Materna , Señales (Psicología) , Diapausa/fisiología , Ciprinodontiformes/fisiología , América del Norte , Embrión no Mamífero
3.
Educ Inf Technol (Dordr) ; 28(6): 6695-6726, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36465416

RESUMEN

Digital technologies have brought changes to the nature and scope of education and led education systems worldwide to adopt strategies and policies for ICT integration. The latter brought about issues regarding the quality of teaching and learning with ICTs, especially concerning the understanding, adaptation, and design of the education systems in accordance with current technological trends. These issues were emphasized during the recent COVID-19 pandemic that accelerated the use of digital technologies in education, generating questions regarding digitalization in schools. Specifically, many schools demonstrated a lack of experience and low digital capacity, which resulted in widening gaps, inequalities, and learning losses. Such results have engendered the need for schools to learn and build upon the experience to enhance their digital capacity and preparedness, increase their digitalization levels, and achieve a successful digital transformation. Given that the integration of digital technologies is a complex and continuous process that impacts different actors within the school ecosystem, there is a need to show how these impacts are interconnected and identify the factors that can encourage an effective and efficient change in the school environments. For this purpose, we conducted a non-systematic literature review. The results of the literature review were organized thematically based on the evidence presented about the impact of digital technology on education and the factors that affect the schools' digital capacity and digital transformation. The findings suggest that ICT integration in schools impacts more than just students' performance; it affects several other school-related aspects and stakeholders, too. Furthermore, various factors affect the impact of digital technologies on education. These factors are interconnected and play a vital role in the digital transformation process. The study results shed light on how ICTs can positively contribute to the digital transformation of schools and which factors should be considered for schools to achieve effective and efficient change.

4.
Hum Reprod ; 36(6): 1611-1620, 2021 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-33846715

RESUMEN

STUDY QUESTION: Does the application of reference ranges for sex steroids and the modified Ferriman-Gallwey (mFG) scale established in the community from which the study sample was drawn, combined with the most conservative polycystic ovary morphology (PCOM) criteria to the recognised diagnostic criteria for polycystic ovary syndrome (PCOS) improve the certainty of diagnosis of PCOS in non-healthcare-seeking women? SUMMARY ANSWER: Despite application of the stringent definitions of the elements used to diagnose PCOS in a non-healthcare seeking community-based sample, the risk of diagnostic uncertainty remains. WHAT IS KNOWN ALREADY: There is heterogeneity in prevalence estimates for PCOS due, in part, to lack of standardisation of the elements comprising the recognised National Institutes of Health (NIH), Rotterdam and Androgen Excess Society (AE-PCOS) diagnostic criteria. The AE-PCOS Society proposed refinements to the definitions of biochemical androgen excess and PCOM that can now be incorporated into these sets of diagnostic criteria to estimate PCOS prevalence. STUDY DESIGN, SIZE, DURATION: An Australian cross-sectional study of 168 non-healthcare-seeking women. PARTICIPANTS/MATERIALS, SETTING, METHODS: The 168 included women were aged 18-39 years, euthyroid and normoprolactinemic, not recently pregnant, breast feeding or using systemic hormones. Each provided menstrual history and assessment of the mFG, had measurement of sex steroids by liquid chromatography, tandem mass spectrometry, and a pelvic ultrasound. The presence of PCOS was determined using modified (m) NIH, Rotterdam, and AE-PCOS criteria according to AE-PCOS Society recommendations. MAIN RESULTS AND THE ROLE OF CHANCE: Overall, 10.1% of the included participants met the mNIH PCOS criteria, which requires the presence of menstrual dysfunction, while 18.5% met the mRotterdam and 17.5% the AE-PCOS criteria, with the latter requiring hyperandrogenism. Eight of the 27 participants with menstrual dysfunction, 10 of 31 women with PCOM, and 39 of 68 women with hyperandrogenism had no other feature of PCOS. Of the 19 participants with hyperandrogenaemia, 10 met the mNIH criteria (52.5%) and 14 met both the mRotterdam and AE-PCOS criteria (78.9%). Women who had the combination of hyperandrogenism and PCOM explained the greatest discrepancy between the mNIH and the other criteria. LIMITATIONS, REASONS FOR CAUTION: Clinical androgenisation relied on participant self-assessment, which has been shown to be valid when compared with clinician assessment. The sample size was a function of both the strict inclusion criteria and the requirements of non-healthcare-seeking women having a blood draw and pelvic ultrasound which may have introduced a selection bias. WIDER IMPLICATIONS OF THE FINDINGS: Despite applying stringent cut-offs for serum androgens, the mFG scale and the ovarian follicle count, these criteria remain arbitrary. Accordingly, healthy women may be captured by these criteria, and misidentified as having PCOS, while women with the condition may be missed. Consequently, PCOS remains a diagnosis to be made with care. STUDY FUNDING/COMPETING INTEREST(S): The study was supported by the Grollo-Ruzzene Foundation. Dr S.R.D. is an NHMRC Senior Principal Research Fellow (Grant no. 1135843). S.R.D. has been paid for developing and delivering educational presentations for Besins Healthcare, BioFemme and Pfizer Australia, has been on Advisory Boards for Theramex, Abbott Laboratories, Mayne Pharmaceuticals and Roche and a consultant to Lawley Pharmaceuticals and Que Oncology and has received has received institutional grant funding for Que Oncology research; there are no other relationships or activities that could appear to have influenced the submitted work. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Síndrome del Ovario Poliquístico , Adolescente , Adulto , Australia , Estudios Transversales , Femenino , Humanos , Síndrome del Ovario Poliquístico/diagnóstico , Síndrome del Ovario Poliquístico/epidemiología , Embarazo , Prevalencia , Valores de Referencia , Adulto Joven
5.
Plant Cell Environ ; 41(2): 395-405, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29194664

RESUMEN

The plant hormone salicylic acid (SA) is recognized as an effective defence against biotrophic pathogens, but its role as regulator of beneficial plant symbionts has received little attention. We studied the relationship between the SA hormone and leaf fungal endophytes on herbivore defences in symbiotic grasses. We hypothesize that the SA exposure suppresses the endophyte reducing the fungal-produced alkaloids. Because of the role that alkaloids play in anti-herbivore defences, any reduction in their production should make host plants more susceptible to herbivores. Lolium multiflorum plants symbiotic and nonsymbiotic with the endophyte Epichloë occultans were exposed to SA followed by a challenge with the aphid Rhopalosiphum padi. We measured the level of plant resistance to aphids, and the defences conferred by endophytes and host plants. Symbiotic plants had lower concentrations of SA than did the nonsymbiotic counterparts. Consistent with our prediction, the hormonal treatment reduced the concentration of loline alkaloids (i.e., N-formyllolines and N-acetylnorlolines) and consequently decreased the endophyte-conferred resistance against aphids. Our study highlights the importance of the interaction between the plant immune system and endophytes for the stability of the defensive mutualism. Our results indicate that the SA plays a critical role in regulating the endophyte-conferred resistance against herbivores.


Asunto(s)
Endófitos/metabolismo , Herbivoria , Lolium/fisiología , Reguladores del Crecimiento de las Plantas/metabolismo , Ácido Salicílico/metabolismo , Alcaloides/metabolismo , Epichloe/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Lolium/microbiología , Reguladores del Crecimiento de las Plantas/fisiología
6.
Nanotechnology ; 28(5): 055101, 2017 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-28029105

RESUMEN

Stimuli-responsive anticancer formulations can promote drug release and activation within the target tumour, facilitate cellular uptake, as well as improve the therapeutic efficacy of drugs and reduce off-target effects. In the present work, indocyanine green (ICG)-containing polyglutamate (PGA) nanoparticles were developed and characterized. Digestion of nanoparticles with cathepsin B, a matrix metalloproteinase overexpressed in the microenvironment of advanced tumours, decreased particle size and increased ICG cellular uptake. Incorporation of ICG in PGA nanoparticles provided the NIR-absorbing agent with time-dependent altered optical properties in the presence of cathepsin B. Having minimal dark toxicity, the formulation exhibited significant cytotoxicity upon NIR exposure. Combined use of the formulation with saporin, a ribosome-inactivating protein, resulted in synergistically enhanced cytotoxicity attributed to the photo-induced release of saporin from endo/lysosomes. The results suggest that this therapeutic approach can offer significant therapeutic benefit in the treatment of superficial malignancies, such as head and neck tumours.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Catepsina B/metabolismo , Sistemas de Liberación de Medicamentos/métodos , Células Epiteliales/efectos de los fármacos , Terapia Molecular Dirigida/métodos , Nanopartículas/química , Proteínas Inactivadoras de Ribosomas Tipo 1/farmacología , Antineoplásicos Fitogénicos/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Colorantes/química , Composición de Medicamentos/métodos , Liberación de Fármacos , Endosomas/efectos de los fármacos , Endosomas/metabolismo , Endosomas/efectos de la radiación , Células Epiteliales/metabolismo , Células Epiteliales/patología , Células Epiteliales/efectos de la radiación , Humanos , Verde de Indocianina/química , Rayos Infrarrojos , Cinética , Lisosomas/efectos de los fármacos , Lisosomas/metabolismo , Lisosomas/efectos de la radiación , Nanopartículas/ultraestructura , Tamaño de la Partícula , Ácido Poliglutámico/química , Proteolisis , Proteínas Inactivadoras de Ribosomas Tipo 1/química , Saporinas
7.
Diabetol Metab Syndr ; 15(1): 237, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37978555

RESUMEN

BACKGROUND AND AIMS: There is a link between genetics with metabolic balance and adiposity homeostasis on metabolic syndrome (MetS). Polymorphism in adipokine genes such as leptin and adiponectin may play an important role in its development. This study aimed to determine the association of the individual and general components of MetS with genetic alterations in LEP (rs7799039 and rs2167270) and ADIPOQ (rs1501299 and rs2241766) genes in the Mexican population. METHODS AND RESULTS: The polymorphisms of the LEP gene rs7799039 and rs2167270, together with rs1501299 and rs2241766 polymorphisms of the ADIPOQ gene were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) on 328 individuals (n = 131 MetS). The rs7799039 under the recessive inheritance model was found to be associated with increased risk of MetS (OR = 2.16, 95% CI = 1.06-4.37), dyslipidemia (OR = 7.97, 95% CI = 2.17-29.36), low HDL (OR = 7.01, 95% CI = 1.65-29.71) and hypertension (OR = 13.02, 95% CI = 1.76-96.44); the heterozygote demonstrate a protective effect on MetS (OR = 0.48, 95% CI = 0.28-0.88) and diabetes (OR = 0.09, 95% CI = 0.02-0.53) under the over the dominant model. Haplotype analysis showed linkage disequilibrium between the SNPs of ADIPOQ rs1501299/rs2241766, and their association as risk factors for low HDL and hypertension. CONCLUSION: The association of rs7799039 with the presence of MetS, suggests a risk factor for the development of dyslipidemia, as well as its heterozygous as a protective factor for DM. There is a linkage disequilibrium between the SNPs of ADIPOQ.

8.
J Genet ; 1022023.
Artículo en Inglés | MEDLINE | ID: mdl-36988133

RESUMEN

Prostate cancer (PCa) is one of the most common types of cancer in men. The aetiology of the disease is not well established, but it has been related to one of the main pathways of regulation of prostate proliferation, mediated by androgens. The androgen receptor (AR) gene encodes the androgen-receptor protein, which functions as a transactivation factor for steroid hormones. It has been proposed that the AR gene transcription levels are mediated by short tandem repeats corresponding to the CAG sequence. However, there are conflicting results in this relationship. We evaluated the expression levels of the AR gene and identified the number of CAG repeats (CAGn) in the Mexican population, establishing the relationship between expression levels and increase in the number of CAG repeats. We evaluated the expression levels of AR in tissue samples of PCa and benign prostate disease, such as benign prostatic hyperplasia, or prostatitis, to determine the difference in their expression levels. Our results showed a statistically insignificant underexpression of 0.64-fold decrease in AR levels of PCa patients compared to benign prostate disease patients (P = 0.623) and suggest that the number of CAGn was correlated with the relative expression of the AR gene (P = 0.009) and this correlation was positive, moderate, and proportional (ρ = 0.467) and no correlation was found between CAGn with other clinical features.


Asunto(s)
Repeticiones de Microsatélite , Hiperplasia Prostática , Neoplasias de la Próstata , Receptores Androgénicos , Humanos , Masculino , Hiperplasia Prostática/genética , Neoplasias de la Próstata/genética , Receptores Androgénicos/genética , Repeticiones de Trinucleótidos/genética
9.
Neurol Res ; 45(2): 112-117, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36184106

RESUMEN

INTRODUCTION: The discontinuation of disease-modifying therapies (DMTs) in multiple sclerosis (MS) is commonly seen in real-world settings due to several factors. AREA COVER: The aim of this study is to describe the frequency of disease activity after discontinuation of DMTs in MS patients included in the Argentinean MS and NMOSD registry. DISCUSION: Patients with relapsing remitting MS (RRMS) and active secondary progressive MS (SPMS) were included based on the following criteria: they discontinued treatment for more than 6 months, they had been treated with a DMT for ≥2 years, and they had at least 6 months of follow-up in the registry after discontinuation. Demographic and clinical data were collected. Disease activity during follow-up was defined as the presence of a clinical relapse or a new magnetic resonance (MRI) lesion (either new lesions on T2-weighted sequence and/or contrast enhancement). Bivariate analysis was applied to identify clinical and demographic factors related to disease activity. CONCLUSION: We included 377 patients (75.5% RRMS, 22.5% SPMS) who had discontinued DMTs. The mean (SD) follow-up after discontinuation was 15.7 (7.9) months. After discontinuation, the presence of relapse was detected in 18.8% and 3.5% in RRMS and SPMS, respectively; and new MRI activity in 22% and 3.5%, respectively. We found that higher risk of relapse and MRI activity was associated with younger age (p < 0.001), shorter disease duration (p < 0.001), and RRMS phenotype (p = 0.006). Males showed higher MRI activity (p 0.011). This study provides real-world data that can guide physicians when considering discontinuation of DMTs.


Asunto(s)
Esclerosis Múltiple Recurrente-Remitente , Esclerosis Múltiple , Masculino , Humanos , Esclerosis Múltiple/tratamiento farmacológico , Argentina/epidemiología , Esclerosis Múltiple Recurrente-Remitente/diagnóstico por imagen , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Esclerosis Múltiple Recurrente-Remitente/patología , Sistema de Registros , Recurrencia
10.
Cancers (Basel) ; 13(7)2021 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-33808284

RESUMEN

BACKGROUND: Quality Indicators for ovarian cancer (OC) have been developed by the European Society of Gynaecological Oncology (ESGO) and by the French National Cancer Institute (Institut National du Cancer, INCa). The aim of the study was to characterize OC care distribution in France by case-volume and to prospectively evaluate the adherence of high-volume institutions to INCa/ESGO quality indicators. METHODS: The cost-utility of radical surgery in ovarian cancer (CURSOC) trial is a prospective, multicenter, comparative and non-randomized study that includes patients with stage IIIC-IV epithelial OC treated in nine French health care tertiary institutions. Adherence to institutional quality indicators were anonymously assessed by an independent committee. OC care distribution in France were provided by the nationwide database of hospital procedures. RESULTS: More than half of patients are treated in low-volume institutions. Among the nine high-volume centers participating in the study, four (44.4%) met all institutional INCa/ESGO quality indicators. The other five (55.6%) did not fulfil one of the quality indicator criteria. CONCLUSIONS: Access to high-volume OC providers in France is restricted to a minority of patients, and yet half of the referral institutions included in this study failed to meet all recommended institutional quality indicators. It is mandatory that national authorities work both to improve OC centralization and to incorporate quality assurance programs into certified centers.

11.
Front Psychol ; 11: 1977, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32922337

RESUMEN

Pregnancy presents some interesting challenges for the philosophy of embodied cognition. Mother and fetus are generally considered to be passive during pregnancy, both individually and in their relation. In this paper, we use the enactive operational concepts of autonomy, agency, individuation, and participation to examine the relation between mother and fetus in utero. Based on biological, physiological, and phenomenological research, we explore the emergence of agentive capacities in embryo and fetus, as well as how maternal agency changes as pregnancy advances. We show that qualitatively different kinds of agency have their beginnings already in utero, and to what extent fetal and maternal movement modulate affectivity and individuation in pregnancy. We thus propose that mother and fetus are both agents who participate in pregnancy. Pregnancy then emerges as a relational developmental organization that anchors and holds its developing participants. We end the paper with reflections on ethical implications of this proposal, and suggestions for future research.

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