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1.
Philos Trans A Math Phys Eng Sci ; 382(2275): 20240057, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38910393

RESUMEN

The Variational Monte Carlo (VMC) method has recently seen important advances through the use of neural network quantum states. While more and more sophisticated ansatze have been designed to tackle a wide variety of quantum many-body problems, modest progress has been made on the associated optimization algorithms. In this work, we revisit the Kronecker-Factored Approximate Curvature (KFAC), an optimizer that has been used extensively in a variety of simulations. We suggest improvements in the scaling and the direction of this optimizer and find that they substantially increase its performance at a negligible additional cost. We also reformulate the VMC approach in a game theory framework, to propose a novel optimizer based on decision geometry. We find that on a practical test case for continuous systems, this new optimizer consistently outperforms any of the KFAC improvements in terms of stability, accuracy and speed of convergence. Beyond VMC, the versatility of this approach suggests that decision geometry could provide a solid foundation for accelerating a broad class of machine learning algorithms. This article is part of the theme issue 'The liminal position of Nuclear Physics: from hadrons to neutron stars'.

2.
Public Health ; 230: 12-20, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38479163

RESUMEN

OBJECTIVE: This article aims to estimate the differences in environmental impact (greenhouse gas [GHG] emissions, land use, energy used, acidification and potential eutrophication) after one year of promoting a Mediterranean diet (MD). METHODS: Baseline and 1-year follow-up data from 5800 participants in the PREDIMED-Plus study were used. Each participant's food intake was estimated using validated semi-quantitative food frequency questionnaires, and the adherence to MD using the Dietary Score. The influence of diet on environmental impact was assessed through the EAT-Lancet Commission tables. The influence of diet on environmental impact was assessed through the EAT-Lancet Commission tables. The association between MD adherence and its environmental impact was calculated using adjusted multivariate linear regression models. RESULTS: After one year of intervention, the kcal/day consumed was significantly reduced (-125,1 kcal/day), adherence to a MD pattern was improved (+0,9) and the environmental impact due to the diet was significantly reduced (GHG: -361 g/CO2-eq; Acidification:-11,5 g SO2-eq; Eutrophication:-4,7 g PO4-eq; Energy use:-842,7 kJ; and Land use:-2,2 m2). Higher adherence to MD (high vs. low) was significantly associated with lower environmental impact both at baseline and one year follow-up. Meat products had the greatest environmental impact in all the factors analysed, both at baseline and at one-year follow-up, in spite of the reduction observed in their consumption. CONCLUSIONS: A program promoting a MD, after one year of intervention, significantly reduced the environmental impact in all the factors analysed. Meat products had the greatest environmental impact in all the dimensions analysed.


Asunto(s)
Dieta Mediterránea , Gases de Efecto Invernadero , Humanos , Dieta , Ambiente , Recolección de Datos
3.
Langenbecks Arch Surg ; 408(1): 206, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37221304

RESUMEN

PURPOSE: Surgery of primary thyroid lymphoma (PTL) has been mostly limited to diagnostic work-up. This study aimed to further study its potential role. METHODS: This was a retrospective study from a multi-institutional registry of PTL patients. Clinical, diagnostic work-up (fine needle aspiration, FNA; core needle biopsy, CoreNB), contribution of surgery (open surgical biopsy, OpenSB; thyroidectomy), histology subtype, and outcome data were evaluated. RESULTS: Some 54 patients were studied. Diagnostic work-up included FNA in 47 patients, CoreNB in 11, and OpenSB in 21. CoreNB yielded the best sensitivity (90.9%). Thyroidectomy was performed in 14 patients with other diagnosis (incidental PTL), in 4 for diagnosis and in 4 for elective treatment of PTL. Incidental PTL was associated with not performed FNA nor CoreNB (OR 52.5; P = 0.008), mucosa-associated lymphoid tissue (MALT) subtype (OR 24.3; P = 0.012), and Hashimoto's thyroiditis (OR 11.1; P = 0.032). Lymphoma-related death (10 cases) mostly occurred within the first year after diagnosis and was associated with diffuse large B-cell (DLBC) subtype (OR 10.3; P = 0.018) and older patients (OR 1.08 for every 1-year increase; P = 0.010). There was a trend towards lower mortality rate in patients receiving thyroidectomy (2/22 versus 8/32, P = 0.172). CONCLUSION: Incidental PTL accounts for most of thyroid surgery cases and are associated with incomplete diagnostic work-up, Hashimoto's thyroiditis and MALT subtype. CoreNB appears to be the best tool for diagnosis. Most of PTL deaths occurred during the first year after diagnosis and mostly related to systemic treatment. Age and DLBC subtype are poor prognostic factors.


Asunto(s)
Linfoma , Neoplasias de la Tiroides , Tiroiditis , Humanos , Estudios Retrospectivos
4.
Actas Dermosifiliogr ; 114(10): 850-857, 2023.
Artículo en Inglés, Español | MEDLINE | ID: mdl-37482291

RESUMEN

BACKGROUND AND OBJECTIVES: There are no clinical guidelines on the management of dysplastic nevus (DN). The aims of this study were to determine the percentage of dermatologists in the center-Spain section of the Spanish Academy of Dermatology and Venereology (AEDV) who would manage a histologically confirmed DN with a watch-and-wait approach or with wider surgical margins and to investigate whether their attitudes would vary depending on whether or not the patient had a personal and/or family history of melanoma. MATERIAL AND METHODS: We collected data from an anonymous survey sent to 738 dermatologists between June 15 and July 31, 2022. The independent variables were degree of dysplasia (low vs. high), margin status (positive vs. negative), and a personal or family history of melanoma (yes vs. no in both cases). The dependent variables were attitude towards management (watch-and-wait vs. re-excision with a surgical margin of 1 to 4mm or re-excision with a surgical margin of 5 to 10mm). RESULTS: We obtained 86 responses to the questionnaire. When pathology indicated a low-grade DN, 60.5% of dermatologists stated they would obtain a surgical margin of 1 to 4mm if the first margins were positive, and 97.7% would watch and wait if the report described negative margins. For high-grade DNs, 1.2% of dermatologists would watch and wait to manage DN with positive margins; 68.8% would use this approach for negative margins. A family or personal history of melanoma had no influence on most of the dermatologists' attitudes. CONCLUSIONS: Management strategies for DN among dermatologists from the center-Spain section of the AEDV varied, particularly when faced with low-grade DN with positive margins and high-grade DN with negative margins. A family or personal history of melanoma did not influence clinical attitudes in most cases.


Asunto(s)
Dermatología , Síndrome del Nevo Displásico , Melanoma , Neoplasias Cutáneas , Venereología , Humanos , Síndrome del Nevo Displásico/cirugía , Síndrome del Nevo Displásico/patología , Márgenes de Escisión , España , Dermatólogos , Melanoma/cirugía , Melanoma/patología , Encuestas y Cuestionarios , Neoplasias Cutáneas/cirugía , Neoplasias Cutáneas/patología
5.
Langenbecks Arch Surg ; 407(8): 3631-3642, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36251077

RESUMEN

PURPOSE: Familial papillary thyroid microcarcinoma (FPTMC) can present a more aggressive behavior than the sporadic microcarcinoma. However, few studies have analyzed this situation. The objective is to analyze the recurrence rate of FPTMC and the prognostic factors which determine that recurrence in Spain. METHODS: Spanish multicenter longitudinal analytical observational study was conducted. Patients with FPTMC received treatment with curative intent and presented cure criteria 6 months after treatment. Recurrence rate and disease-free survival (DFS) were analyzed. Two groups were analyzed: group A (no tumor recurrence) vs. group B (tumor recurrence). RESULTS: Ninety-four patients were analyzed. During a mean follow-up of 73.3 ± 59.3 months, 13 recurrences of FPTMC (13.83%) were detected and mean DFS was 207.9 ± 11.5 months. There were multifocality in 56%, bilateral thyroid involvement in 30%, and vascular invasion in 7.5%; that is to say, they are tumors with histological factors of poor prognosis in a high percentage of cases. The main risk factors for recurrence obtained in the multivariate analysis were the tumor size (OR: 2.574, 95% CI 1.210-5.473; p = 0.014) and the assessment of the risk of recurrence of the American Thyroid Association (ATA), both intermediate risk versus low risk (OR: 125, 95% CI 10.638-1000; p < 0.001) and high risk versus low risk (OR: 45.454, 95% CI 5.405-333.333; p < 0.001). CONCLUSION: FPTMC has a recurrence rate higher than sporadic cases. Poor prognosis is mainly associated with the tumor size and the risk of recurrence of the ATA.


Asunto(s)
Carcinoma Papilar , Neoplasias de la Tiroides , Humanos , Carcinoma Papilar/genética , Carcinoma Papilar/patología , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/cirugía , Supervivencia sin Enfermedad , Pronóstico , Estudios Retrospectivos , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/patología
6.
J Endocrinol Invest ; 44(6): 1327-1330, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32909176

RESUMEN

INTRODUCTION: The prognosis of MEN 1 patients is not only determined by pancreatic disease; it is also related to other uncommon tumors. The objective of this study is to analyze the tumors associated with MEN 1 outside the classic triad and to investigate their relationship with mortality. MATERIALS AND METHODS: One hundred and five MEN 1 patients were studied in a tertiary referral hospital (1980-2019). RESULTS: With a follow-up of 11 ± 4 years, seven patients died (8%), four as a consequence MEN syndrome. Thirty-three percent had adrenal gland tumors. One patient died of adrenal cancer. Eight percent presented with a neuroendocrine thoracic neoplasm, and one patient died. Another patient died due to cutaneous T-cell lymphoma. A further patient died because of a gastrinoma with liver metastasis. CONCLUSIONS: To conclude, 75% of MEN-related deaths were the result of an uncommon pathology, and we, therefore, recommend that these tumors should be taken into account in the screening and follow-up of these patients.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales , Gastrinoma , Linfoma Cutáneo de Células T , Neoplasia Endocrina Múltiple Tipo 1 , Tumores Neuroendocrinos , Neoplasias Torácicas , Neoplasias de las Glándulas Suprarrenales/mortalidad , Neoplasias de las Glándulas Suprarrenales/patología , Causas de Muerte , Estudios de Cohortes , Detección Precoz del Cáncer/métodos , Detección Precoz del Cáncer/normas , Femenino , Estudios de Seguimiento , Gastrinoma/mortalidad , Gastrinoma/patología , Humanos , Linfoma Cutáneo de Células T/mortalidad , Linfoma Cutáneo de Células T/patología , Masculino , Persona de Mediana Edad , Neoplasia Endocrina Múltiple Tipo 1/diagnóstico , Neoplasia Endocrina Múltiple Tipo 1/mortalidad , Neoplasia Endocrina Múltiple Tipo 1/patología , Estadificación de Neoplasias , Tumores Neuroendocrinos/mortalidad , Tumores Neuroendocrinos/patología , Pronóstico , España/epidemiología , Neoplasias Torácicas/mortalidad , Neoplasias Torácicas/patología
7.
Lupus ; 28(3): 396-405, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30760090

RESUMEN

BACKGROUND: Antibodies to M-type phospholipase A2 receptor (a-PLA2R) have been identified in most patients with idiopathic membranous nephropathy, but the prevalence in membranous lupus nephritis (MLN) is still unclear. The objective of this study was to assess the prevalence of a-PLA2R antibodies in a large cohort of patients with lupus nephritis. METHODS: a-PLA2R antibodies were measured by ELISA in serum from patients with systemic lupus erythematosus ( n = 190), of whom 37 had a biopsy-proven MLN. Positive samples were confirmed by commercial ELISA kit, Western blot and immunohistochemistry in renal tissue. RESULTS: A total of 10 from 190 patients (5.3%) with systemic lupus erythematosus had circulating a-PLA2R measured by in-house ELISA assay. The antibodies were detected in 7 patients with MLN (18.9%) and 3 patients with non-renal lupus disease (3.2%). PLA2R staining was detected in the kidney biopsy of 5 of the 7 (71.4%) patients with MLN. a-PLA2R levels were associated with active disease but not proteinuria levels. Presence of a-PLA2R antibodies at baseline was associated with worse remission rates and longer time to remission compared to those patients serologically negative. CONCLUSIONS: a-PLA2R antibodies can be detected with low prevalence in MLN patients, but their detection is associated with a worse renal prognosis.


Asunto(s)
Autoanticuerpos/inmunología , Nefritis Lúpica/inmunología , Receptores de Fosfolipasa A2/inmunología , Adulto , Autoanticuerpos/sangre , Biomarcadores/sangre , Western Blotting , Estudios de Casos y Controles , Progresión de la Enfermedad , Ensayo de Inmunoadsorción Enzimática , Femenino , Glomerulonefritis Membranosa/diagnóstico , Humanos , Riñón/inmunología , Estudios Longitudinales , Nefritis Lúpica/clasificación , Nefritis Lúpica/diagnóstico , Masculino , Valor Predictivo de las Pruebas , Proteinuria , Receptores de Fosfolipasa A2/sangre , Estudios Retrospectivos
8.
J Fluoresc ; 29(1): 15-25, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30361861

RESUMEN

The discoloration of methylene blue in aqueous solution was studied under illumination by a fluorescent lamp, LEDs of red, green, and blue light, and a UV-A black light bulb. Overall results showed that methylene blue was discolored with and without the presence of any photoactive semiconductor. Outcomes depended on the combination substrate-light source employed. Photosensitization was assumed as the discoloration mechanism followed upon visible light irradiation. Fluorescence spectroscopy and high-performance liquid chromatography were used to investigate the possible intermediates formed in the irradiated solutions. The detailed nature of formed species was not stablished, but it was proved that the dye molecule photo-bleached and partially defragmented in several intermediates including leuco dyes, demethylated phenothiazine dyes, and probably humic substances. Since the fluorescence intermediates found were similar for most of the irradiated solutions, it was assumed that comparable reactive species were responsible for the discoloration of the molecule in solution. Results proved the misconception of discoloration experiments found in the literature when employing visible light near the absorption region of the dye.

9.
Immun Ageing ; 16: 14, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31312227

RESUMEN

BACKGROUND: Seasonal influenza virus infection is a significant cause of morbimortality in the elderly. However, there is poor vaccine efficacy in this population due to immunosenescence. We aimed to explore several homeostatic parameters in the elderly that could impact influenza vaccine responsiveness. METHODS: Subjects (> 60 years old) who were vaccinated against influenza virus were included, and the vaccine response was measured by a haemagglutination inhibition (HAI) test. At baseline, peripheral CD4 and CD8 T-cells were phenotypically characterized. Thymic function and the levels of different inflammation-related biomarkers, including Lipopolysaccharide Binding Protein (LBP) and anti-cytomegalovirus (CMV) IgG antibodies, were also measured. RESULTS: Influenza vaccine non-responders showed a tendency of higher frequency of regulatory T-cells (Tregs) before vaccination than responders (1.49 [1.08-1.85] vs. 1.12 [0.94-1.63], respectively, p = 0.061), as well as higher expression of the proliferation marker Ki67 in Tregs and different CD4 and CD8 T-cell maturational subsets. The levels of inflammation-related biomarkers correlated with the frequencies of different proliferating T-cell subsets and with thymic function (e.g., thymic function with D-dimers, r = - 0.442, p = 0.001). CONCLUSIONS: Age-related homeostatic dysregulation involving the proliferation of CD4 and CD8 T-cell subsets, including Tregs, was related to a limited responsiveness to influenza vaccination and a higher inflammatory status in a cohort of elderly people.

10.
Eur J Public Health ; 29(6): 1011-1018, 2019 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-30932155

RESUMEN

BACKGROUND: It is important for teenagers to have a favorable attitude toward organ donation and transplantation (ODT) in order to increase the number of future donors. To determine the attitude of teenagers in the South East of Spain toward ODT and to analyze the psychosocial variables related to this attitude. METHODS: The study population consisted of young teenagers in the South East of Spain. A stratified sample was selected by geographical location, sex and age (n = 4, 117). Attitude was assessed using a validated questionnaire about ODT (PCID-ODT Ríos). Statistical analysis: Student's t-test, Chi-squared test and a multivariate analysis. RESULTS: The questionnaire completion rate was 87% (n = 3572). Attitude toward ODT was favorable in 46% of cases (n = 1633) and undecided in 43% (n = 1543). Several psychosocial variables had a favorable effect on donation: believing that one has good information about ODT (Odds Ratio [OR] 1.706); discussing the subject with the family (OR 1.543) and friends (OR 1.818); carrying out pro-social activities (OR 1.642); having a favorable attitude toward cremation (OR 1.466) and autopsy (OR 1.470); and, finally, not being afraid of scars (OR 4.184). CONCLUSIONS: Teenagers in the South East of Spain are not currently inclined to support organ donation. This attitude is related to many psychosocial factors, mainly connected to not having good information about the subject, not discussing it in social circles and the fear of body mutilation. It would be appropriate to create educational interventional strategies in this group to prevent a negative impact on future donation rates.


Asunto(s)
Actitud , Obtención de Tejidos y Órganos , Adolescente , Niño , Femenino , Humanos , Masculino , Medios de Comunicación de Masas , Comunicación Persuasiva , España , Encuestas y Cuestionarios
11.
Ethn Health ; 24(4): 443-461, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-28665141

RESUMEN

INTRODUCTION: Medical students represent a new generation of medical thought, and if they have a favourable attitude towards organ donation this will greatly encourage its promotion. OBJECTIVE: To analyse the attitude of medical students in Spanish universities towards the donation of their own organs and to determine the factors affecting this attitude. MATERIAL AND METHODS: Type of study: A sociological, interdisciplinary, multicentre, and observational study in Spain. STUDY POPULATION: Students studying a degree in medicine enrolled in Spain (n = 34,000). SAMPLE SIZE: A sample of 9598 students (confidence of 99% and precision of ±1%), stratified by geographical area and academic year. Instrument of measurement: A validated questionnaire of attitude towards organ donation and transplantation (PCID-DTO RIOS) was self-administered and completed anonymously. RESULTS: The questionnaire completion rate was 95.7% (n = 9.275). 80% were in favour of donation, 2% against and 18% were undecided. The following main variables were related to a favourable attitude: being of the female sex (Odds Ratio = 1.739); being in the sixth year of the degree (OR = 2.506); knowing a donor (OR = 1.346); having spoken about the subject with one's family (OR = 2.132) and friends (OR = 1.333); having a family circle that is in favour, more specifically, having a father (OR = 1.841), mother (OR = 2.538) or partner in favour (OR = 2.192); being a blood donor (OR = 2.824); acceptance of the mutilation of the body if it were necessary (OR = 2.958); and being an atheist or an agnostic (OR = 1.766). CONCLUSIONS: Spanish medical students generally have a favourable attitude towards organ donation, although 20% are not in favour.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Estudiantes de Medicina/psicología , Obtención de Tejidos y Órganos/estadística & datos numéricos , Adulto , Femenino , Humanos , Masculino , España , Encuestas y Cuestionarios , Donantes de Tejidos/provisión & distribución
12.
Folia Biol (Praha) ; 65(5-6): 237-245, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32362307

RESUMEN

Several studies have shown that peroxynitrite (ONOO-), formed upon the reaction of •NO and O2-, is increased in many cardiovascular diseases and is detrimental to myocardial function. Proteins associated with Ca2+ homeostasis regulation in the heart may be involved in these effects. Thus, the aim of this study was to elucidate the mechanisms associated with ONOO--induced effects. We evaluated [Ca2+]i regulation, sarco/endoplasmic reticulum Ca2+- binding proteins, and phosphorylation levels of the ryanodine receptor in isolated rat myocytes. Electrical field-induced intracellular Ca2+ transients and contractions were recorded simultaneously. Myocytes superfused with 3-morpholinosydnonimine N-ethylcarbamide (SIN-1), an ONOO- donor, decreased the amplitude of Ca2+ transients and contraction in a dose-response (1-200 µM) manner. Similarly, SIN-1 increased half-time decay in a concentration-dependent manner. Co-infusion of the ONOO- donor with FeTMPyP (1 µM), an ONOO- decomposition catalyst, inhibited the effects induced by ONOO-. Impaired sarcoplasmic reticulum Ca2+ uptake caused by ONOO- (SIN-1 200 µM) was confirmed by a reduction of caffeine-evoked Ca2+ release along with prolongation of the half-time decay. Surprisingly, ONOO- induced a spontaneous Ca2+ transient that started at the beginning of the relaxation phase and was inhibited by tetracaine. Also, reduced phosphorylation at the ryanodine receptor 2 (RyR2)-Ser-2814 site was observed. In conclusion, deficient sarco/endoplasmic reticulum Ca2+-ATPase-mediated Ca2+ uptake concomitant with augmented Ca2+ release by RyR2 in myocytes may be associated with modification of myocyte Ca2+ handling by ONOO-. Thus, development of cardiac failure in diabetes, nephropathy, or hypertension may be related with elevated ONOO- in cardiac tissue.


Asunto(s)
Calcio/metabolismo , Retículo Endoplásmico/metabolismo , Espacio Intracelular/metabolismo , Miocitos Cardíacos/metabolismo , Ácido Peroxinitroso/metabolismo , Animales , Cafeína/farmacología , Retículo Endoplásmico/efectos de los fármacos , Masculino , Proteínas de Transporte de Membrana/metabolismo , Molsidomina/análogos & derivados , Molsidomina/farmacología , Contracción Miocárdica/efectos de los fármacos , Miocitos Cardíacos/efectos de los fármacos , Fosforilación/efectos de los fármacos , Ratas Wistar , Tetracaína/farmacología
14.
Med Vet Entomol ; 32(4): 490-496, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29884992

RESUMEN

The Mediterranean recluse spider, Loxosceles rufescens (Dufour, 1820) (Araneae: Sicariidae) is a cosmopolitan spider that has been introduced in many parts of the world. Its bite can be dangerous to humans. However, the potential distribution of this alien species, which is able to spread fairly quickly with human aid, is completely unknown. Using a combination of global and regional niche models, it is possible to analyse the spread of this species in relation to environmental conditions. This analysis found that the successful spreading of this species varies according to the region invaded. The majority of populations in Asia are stable and show niche conservatism, whereas in North America this spider is expected to be less successful in occupying niches that differ from those in its native region and that do not support its synanthropic way of living.


Asunto(s)
Ecosistema , Especies Introducidas , Modelos Biológicos , Arañas/fisiología , Animales , Asia/epidemiología , Entorno Construido , Clima , Actividades Humanas , Humanos , Región Mediterránea/epidemiología , América del Norte/epidemiología , Picaduras de Arañas/epidemiología , Picaduras de Arañas/patología , Temperatura
15.
Appl Opt ; 57(15): 4331-4336, 2018 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-29791413

RESUMEN

The simultaneous measurement of the numerical aperture (NA) and mode field diameter (MFD) of single-mode fibers was performed on several commercial fibers by means of digital image processing of the output light projected into a screen. In addition, the changes induced by core diffusion in an ultra-high (UH) NA fiber at several heat depositions from a CO2 laser source were measured. The measurement method was demonstrated to be useful to monitor the adiabaticity of this process, by taking the product of the NA and MFD to verify if it remains constant. The method provides a cheap alternative to measure these optical fiber parameters by using simple optomechanical elements and a readily available smartphone camera, and it can be easily implemented in the laboratory.

17.
J Assist Reprod Genet ; 35(2): 237-245, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28990130

RESUMEN

PURPOSE: The aim of this study is to evaluate which cryopreservation protocol, freezing before or after swim-up, optimizes cryopreservation outcomes in terms of motile sperm count, motility, morphology, and viability, and also to establish whether sperm viability could be assessed based on sperm motility. METHODS: Fifty-three fresh and 53 swim-up prepared samples were considered for the first experiment. In parallel, total motility evaluation by CASA system (computer-assisted sperm analyzer) and hypoosmotic swelling test (HOS-test) was performed in each sample to compare the viability results of both methods. In the second experiment, 21 normozoospermic semen samples and 20 semen samples from male factor patients were included. After fresh ejaculate evaluation, the semen sample of each patient was divided into two aliquots, one of them was frozen before swim-up and the other was frozen after swim-up. Motility, sperm count, morphology, and viability were evaluated after thawing. RESULTS: A linear regression model allows prediction of HOS-test viability results based on total motility: HOS = 1.38 + 0.97 · TM (R 2 = 99.10, residual mean squares = 9.51). Freezing before sperm selection leads to higher total and progressive motility, total motile sperm count, and viability rates than when sperm selection is performed before freezing (P < 0.005 in all cases). In fact, sperm selection prior to freezing reaches critical values when subfertile patients are considered. CONCLUSIONS: To conclude, total motility evaluation can predict HOS-test viability results, resulting in a more objective and less time-consuming method to assess viability. In addition, sperm freezing prior to swim-up selection must be considered in order to achieve better outcomes after thawing, especially in patients presenting poor sperm baseline.


Asunto(s)
Criopreservación/métodos , Preservación de Semen/métodos , Espermatozoides/fisiología , Supervivencia Celular , Congelación , Humanos , Masculino , Estudios Prospectivos , Recuento de Espermatozoides , Motilidad Espermática , Espermatozoides/citología
18.
Int J Phytoremediation ; 20(13): 1354-1361, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30666892

RESUMEN

The remediation of contaminated dredged sediments is necessary to eliminate the risk towards human beings or the environment when there is disposal on land. A greenhouse experiment was carried out to evaluate the chemically assisted phytoextraction to clean up dredged sediment contaminated with Cr, Cu, Pb, and Zn. The ability of castor bean and chicory to absorb, translocate, and accumulate metals from sediment to root and shoot was evaluated by applying EDTA (5 mM), NTA (5 mM), and citric acid (60 mM) to sediment, before the harvest. Citric acid 60 mM was the most effective treatment in increasing Cr, Cu, and Pb in castor bean and chicory shoot. Chicory could accumulate 1730 mg Cr kg-1 in shoot, and had greater values than one for the bioaccumulation and translocation factors when citric acid was added to the sediment. But, the Cr percentages removed per harvest of chicory were 0.05% and were lower for Cu, Pb, and Zn due to low biomass obtained. Citric acid-assisted phytoextraction with chicory can be a promising short time solution to reduce Cr concentration in sediment and reach the Cr level guide for industrial land use only if suitable agronomic practices could be implemented to increase crop yield.


Asunto(s)
Cichorium intybus , Metales Pesados/análisis , Ricinus communis , Contaminantes del Suelo/análisis , Biodegradación Ambiental , Ácido Cítrico , Ácido Edético , Humanos , Ricinus
19.
J Therm Biol ; 78: 298-303, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30509651

RESUMEN

Temperature is one of the most important environmental variables for organisms, especially for ectothermic animals. In fact, ectotherms must move within a relatively narrow range of temperatures where they are able to maximize their performance. We assessed the thermal ecology of female sand spiders (Sicarius thomisoides) in Chile from separate populations along an environmental gradient and different macro habitats (coast vs. inland locations). The parameters of thermal performance curves do not vary between populations, with an average optimum temperature (T°opt) of 25.33 ±â€¯2.65 °C, and a CT min and CT max of 6.56 ±â€¯1.72 °C and 44.23 ±â€¯4.92 °C, respectively. Our results show that the thermal niche in laboratory is conserved and does not vary along an environmental gradient coinciding with the temperatures selected by female spiders in their microhabitats.


Asunto(s)
Conducta Animal , Temperatura Corporal , Ecosistema , Arañas/fisiología , Animales , Femenino
20.
Artículo en Inglés | MEDLINE | ID: mdl-28559274

RESUMEN

We explored if baseline CD4/CD8 T-cell ratio is associated with immunodiscordant response to antiretroviral therapy in HIV-infected subjects. Comparing immunodiscordant and immunoconcordant subjects matched by pretreatment CD4 counts, we observed a lower pretreatment CD4/CD8 T-cell ratio in immunodiscordant subjects. Furthermore, pretreatment CD4/CD8 T-cell ratio, but not CD4 counts, correlated with the main immunological alterations observed in immunodiscordants, including increased regulatory T-cell (Treg) frequency and T-cell turnover-related markers. Then, in a larger cohort, only baseline CD4/CD8 T-cell ratio was independently associated with immunodiscordance, after adjusting by the viral CXCR4-tropic HIV variants. Our results suggest that the CD4/CD8 T-cell ratio could be an accurate biomarker of the subjacent immunological damage triggering immunodiscordance.


Asunto(s)
Terapia Antirretroviral Altamente Activa/métodos , Relación CD4-CD8 , Linfocitos T CD8-positivos/inmunología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , Linfocitos T Reguladores/inmunología , Adulto , Fármacos Anti-VIH/uso terapéutico , Biomarcadores/metabolismo , Supervivencia Celular/efectos de los fármacos , Didanosina/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Receptores CXCR4/inmunología , Estavudina/uso terapéutico , Carga Viral , Zalcitabina/uso terapéutico , Zidovudina/uso terapéutico
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