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1.
Transfus Apher Sci ; 63(5): 103983, 2024 Aug 02.
Article in English | MEDLINE | ID: mdl-39098276

ABSTRACT

Adequate stem cell harvesting is required for autologous hematopoietic transplantation. In deficient mobilizer patients, the collection of stem cells can be challenging because of the impossibility of achieving satisfactory CD34 cell counts with GCSF + - chemotherapy. Plerixafor is a potent and expensive drug that promotes the release of stem cells from the medullary niche to the peripheral blood and allows satisfactory harvests. We performed a retrospective analysis of 370 patients with myeloma and lymphoma harvested at our institution. 99 % of patients achieved satisfactory apheresis using Plerixafor in 45 %. Satisfactory harvests were obtained in patients mobilized with GCSF or plerixafor. In patients who used plerixafor, it was necessary to perform fewer apheresis procedures (P = 0.05). In multivariate analysis, the only factor that predicted the need for plerixafor was the presence of less than 30,000 CD34 / ul on the day of apheresis (OR 0.3. p < 0.001). Since we adopted the plerixafor protocol guided by CD34 counts, the number of patients with harvest failure has decreased. In conclusion, the rational and standardized use of plerixafor favors satisfactory harvest in patients who require autologous transplantation in South-American patients.

2.
Development ; 144(20): 3698-3705, 2017 10 15.
Article in English | MEDLINE | ID: mdl-28870990

ABSTRACT

The advent of stem cell-derived retinal organoids has brought forth unprecedented opportunities for developmental and physiological studies, while presenting new therapeutic promise for retinal degenerative diseases. From a translational perspective, organoid systems provide exciting new prospects for drug discovery, offering the possibility to perform compound screening in a three-dimensional (3D) human tissue context that resembles the native histoarchitecture and to some extent recapitulates cellular interactions. However, inherent variability issues and a general lack of robust quantitative technologies for analyzing organoids on a large scale pose severe limitations for their use in translational applications. To address this need, we have developed a screening platform that enables accurate quantification of fluorescent reporters in complex human iPSC-derived retinal organoids. This platform incorporates a fluorescence microplate reader that allows xyz-dimensional detection and fine-tuned wavelength selection. We have established optimal parameters for fluorescent reporter signal detection, devised methods to compensate for organoid size variability, evaluated performance and sensitivity parameters, and validated this technology for functional applications.


Subject(s)
Genetic Techniques , Induced Pluripotent Stem Cells/cytology , Organoids/physiology , Retina/physiology , Cell Culture Techniques , Cell Differentiation , Cell Line , Fluorescent Dyes , Genes, Reporter , Humans , Microscopy, Fluorescence , Oxidative Stress , Stem Cell Transplantation , Transgenes , Translational Research, Biomedical
3.
Chem Senses ; 45(7): 493-502, 2020 10 09.
Article in English | MEDLINE | ID: mdl-32556127

ABSTRACT

The chemical senses of taste and smell play a vital role in conveying information about ourselves and our environment. Tastes and smells can warn against danger and also contribute to the daily enjoyment of food, friends and family, and our surroundings. Over 12% of the US population is estimated to experience taste and smell (chemosensory) dysfunction. Yet, despite this high prevalence, long-term, effective treatments for these disorders have been largely elusive. Clinical successes in other sensory systems, including hearing and vision, have led to new hope for developments in the treatment of chemosensory disorders. To accelerate cures, we convened the "Identifying Treatments for Taste and Smell Disorders" conference, bringing together basic and translational sensory scientists, health care professionals, and patients to identify gaps in our current understanding of chemosensory dysfunction and next steps in a broad-based research strategy. Their suggestions for high-yield next steps were focused in 3 areas: increasing awareness and research capacity (e.g., patient advocacy), developing and enhancing clinical measures of taste and smell, and supporting new avenues of research into cellular and therapeutic approaches (e.g., developing human chemosensory cell lines, stem cells, and gene therapy approaches). These long-term strategies led to specific suggestions for immediate research priorities that focus on expanding our understanding of specific responses of chemosensory cells and developing valuable assays to identify and document cell development, regeneration, and function. Addressing these high-priority areas should accelerate the development of novel and effective treatments for taste and smell disorders.


Subject(s)
Olfaction Disorders/therapy , Taste Disorders/therapy , Congresses as Topic , Genetic Therapy , Humans , Olfaction Disorders/pathology , Regenerative Medicine , Small Molecule Libraries/therapeutic use , Stem Cell Transplantation , Stem Cells/cytology , Stem Cells/metabolism , Taste Disorders/pathology
5.
J Viral Hepat ; 25(11): 1280-1286, 2018 11.
Article in English | MEDLINE | ID: mdl-29851225

ABSTRACT

Chronic hepatitis C treatment with direct acting antiviral (DAA) therapy during incarceration is an attractive option, due to its short duration and to the possibility of directly observed treatment or supervision. The aim of this study is to compare the effectiveness and rates of discontinuation of DAA treatment in prisoners and nonprisoners. We studied all patients treated in the 10 prisons of Catalonia and at 3 public hospitals in the Barcelona area between 1 January 2015 and 30 April 2016. We analysed sustained viral response (SVR) and rates of discontinuation through intention-to-treat and modified-intention-to-treat analyses, the latter excluding discontinuations due to release from prison. One hundred and eighty-eight inmates and 862 noninmates were included. Prisoners were significantly younger than nonprisoners, with higher proportions of men, drug users, HIV infection, genotypes 1a and 3 and more treatment with psychiatric drugs. Overall, 98.4% of patients completed treatment. The discontinuation rate was low, but higher in inmates (3.7% vs 1.2% noninmates; P = .003) and in community patients >65 years old (2.8% vs 1.2% in under 65 seconds; P = .008). Among the inmates, 7 (42.8%) discontinuations were due to release. SVR was 93.1% in inmates vs 96.5% in noninmates (P = .08) by intention-to-treat and 95.1% vs 96.5% (P = .37) by modified intention-to-treat. Virologic failure rates were similar (3.8% vs 3% in noninmates; P = .60). SVR, virologic failure and discontinuation rates were similar in inmates and noninmates. Currently, prisons are considered a priority for the implementation of DAA. Improved coordination between penitentiary and community health systems would help to ensure therapeutic continuity in released prisoners.


Subject(s)
Antiviral Agents/therapeutic use , Hepatitis C, Chronic/drug therapy , Medication Adherence/statistics & numerical data , Prisoners/statistics & numerical data , Adult , Aged , Aged, 80 and over , Antiviral Agents/pharmacology , Female , Genotype , Hepacivirus/drug effects , Hepacivirus/genetics , Hepatitis C, Chronic/epidemiology , Hepatitis C, Chronic/virology , Humans , Intention to Treat Analysis , Male , Middle Aged , Retrospective Studies , Risk Factors , Spain/epidemiology , Treatment Outcome , Viral Load/drug effects , Young Adult
6.
Opt Lett ; 42(6): 1145-1148, 2017 Mar 15.
Article in English | MEDLINE | ID: mdl-28295069

ABSTRACT

In this Letter, we describe a very general procedure to obtain a causal fit of the permittivity of materials from experimental data with very few parameters. Unlike other closed forms proposed in the literature, the uniqueness of this approach lies in its independence on the material or frequency range at stake. Many illustrative numerical examples are given, and the accuracy of the fitting is compared to other expressions in the literature.

7.
J Intern Med ; 280(2): 209-20, 2016 08.
Article in English | MEDLINE | ID: mdl-26864622

ABSTRACT

Obesity, which affects 600 million adults worldwide, is a major risk factor for type 2 diabetes (T2D) and insulin resistance. Current therapies for these metabolic disorders include weight management by lifestyle intervention or bariatric surgery and pharmacological treatment with the aim of regulating blood glucose. Probably because of their short-term effectiveness, these therapies have not been able to stop the rapidly rising prevalence of T2D over the past decades, highlighting an urgent need to develop new therapeutic strategies. The role of immune cells, such as macrophages, in insulin resistance has been extensively studied. Major advances have been made to elucidate the role of adipose tissue macrophages in these pathogeneses. Recently, anti-inflammatory drugs have been suggested as an alternative treatment for T2D, and clinical trials of these agents are currently ongoing. In addition, results of previous clinical trials using antibodies against inflammatory cytokines, which showed modest effects, are now being rigorously re-evaluated. However, it is still unclear how liver macrophages [termed Kupffer cells (KCs)], which constitute the major source of macrophages in the body, contribute to the development of insulin resistance. In this review, we will discuss the present understanding of the role of liver immune cells in the development of insulin resistance. We will particularly focus on KCs, which could represent an attractive target for the treatment of metabolic diseases.


Subject(s)
Insulin Resistance/immunology , Kupffer Cells/immunology , Liver/immunology , Animals , Diabetes Mellitus, Type 2/immunology , Hepatitis/immunology , Hepatocytes/immunology , Humans , Obesity/immunology
8.
Ginecol Obstet Mex ; 84(8): 475-83, 2016 08.
Article in Spanish | MEDLINE | ID: mdl-29424508

ABSTRACT

Background: The prevalence of cervicovaginal infections during pregnancy has been associated with adverse perinatal outcomes however, the actual approach used for diagnosis is not effective. The aim of this study was to compare the diagnosis of vaginal infections in pregnant women using clinical, molecular diagnostic and traditional microbiological culture in a pilot study, to determine the prevalence and association with the development of preterm labor. Materials and methods: We performed a nested cross-sectional study composed by 54 women in a cohort of pregnant women in Mexico City. Cervicovaginal infections were evaluated by clinical methods, microbiology culture and a commercially available molecular biology test. Results: Prevalence of cervicovaginal infections during pregnancy was estimated between 28% and 50% according to methodologies. Considering the clinical diagnosis of preterm labor as the gold standard, all diagnostic tests were poor as predictors of preterm labor. Conclusion: Traditional approaches to establish the significance of cervicovaginal infection in pregnancy are exhausted, so be sought new ways to understand this complex relationship. Meanwhile it is recommended to continue to use traditional methods to identify infections during pregnancy in both knowledge of new methods aimed at understanding these relationships are sophisticated.


Subject(s)
Molecular Diagnostic Techniques/methods , Pregnancy Complications, Infectious/diagnosis , Uterine Cervical Diseases/diagnosis , Vaginal Diseases/diagnosis , Adolescent , Adult , Cohort Studies , Cross-Sectional Studies , Female , Humans , Mexico , Obstetric Labor, Premature/epidemiology , Pilot Projects , Pregnancy , Pregnancy Complications, Infectious/microbiology , Pregnancy Outcome , Uterine Cervical Diseases/microbiology , Vaginal Diseases/microbiology , Young Adult
9.
Ginecol Obstet Mex ; 84(8): 514-22, 2016 08.
Article in Spanish | MEDLINE | ID: mdl-29424513

ABSTRACT

Background: In Mexico, the prevalence of caesarean section is 40.9% in the health sector, the techniques used are the traditional Pfannenstiel-Kerr and Kerr-half infraumbilical and little experience with this new technique Misgav-Ladach modified. Objetive: To compare pregnancy outcomes (surgical and fetal extraction time, bleeding, postoperative pain, surgical wound infection, maternal and fetal death) caesarean section techniques modified Misgav-Ladach, Pfannenstiel-Kerr and infraumbilical. Material and method: Clinical trial in primiparous women with term pregnancy treated at the Medical Unit of High Specialty 23 of the Mexican Social Security Institute, Monterrey, Nuevo Leon, Mexico. Misgav-Ladach caesarean Caesarean modified and Kerr, the latter subdivided into two groups: infraumbilical Pfannenstiel incision and incision half-Kerr two groups patients were randomized. Results: 137 gilts were studied, with term pregnancy and BMI between 19 and 24.9 kg / m2. Caesarean modified Misgav-Ladach 68 patients and 69 classical Kerr (35 Pfannenstiel-Kerr and 34 infraumbilical) was performed. The surgical time in minutes was lower with modified Misgav-Ladach: 27.8 ± 8.0, Pfannenstiel-Kerr recorded 51.7 ± 12.1 and 12.0 ± infraumbilical media48.3 (p = 0.000). The time in seconds fetal extraction was lower in modified Misgav-Ladach: 96.2 ± 68.3, 474.9 ± Pfannenstiel-Kerr 294.1 and 423.2 ± 398.6 infraumbilical (p = 0.000). The trasoperatory milliliters bleeding was lower with modified Misgav-Ladach: 298.5 ± 57.3, 354.3 ± Pfannenstiel-Kerr 98.0 and 355.9 ± 110.6 infraumbilical (p = 0.001). Postoperative pain assessed with the visual analog scale in the first 24 hours was lower with modified Misgav-Ladach: 4.4 ± 1.9, 5.7 ± Pfannenstiel-Kerr and IK 2.1 6.1 ± 2.0 (p = 0.000). The start of the oral route and ambulation Nwas soon comparing modified Misgav-Ladach against Pfannenstiel-Kerr and Kerr-infraumbilical (p = 0.000). The prevalence of fever was 5.9% with modified Misgav-Ladach, 5.9% Pfannenstiel-Kerr and 32.4% withinfraumbilical-Kerr (p = 001). The discharge in hours was modified Misgav-Ladach ± 45.8 to 12.1 h, Pfannenstiel-Kerr 49.3 ± 12.3 h and 58.5 infraumbilical-Kerr ± 21.5 h (p = .000). In this study no maternal or fetal deaths were observed. Conclusion: Surgical time, bleeding, postoperative pain, better postoperative recovery and shorter hospital stays and less infection were significantly lower than with conventional techniques of caesarean Nsection or infraumbilical-Kerr technique.


Subject(s)
Cesarean Section/methods , Pain, Postoperative/epidemiology , Pregnancy Outcome , Surgical Wound Infection/epidemiology , Adult , Body Mass Index , Female , Humans , Length of Stay , Mexico , Operative Time , Pain Measurement , Pregnancy , Young Adult
10.
J Eur Acad Dermatol Venereol ; 28(5): 633-40, 2014 May.
Article in English | MEDLINE | ID: mdl-23556501

ABSTRACT

BACKGROUND: Dermatomycoses are superficial fungal infections of the skin, hair and nails that affect more than 20-25% of the people worldwide. These infections can be caused by yeasts, dermatophytes and non-dermatophyte filamentous fungi (NDFF) and are considered a public health problem. Despite this, few studies have investigated the prevalence and antifungal susceptibility of causative agents of dermatomycoses in the developing world. OBJECTIVES: The aims of this study were to identify and determine the antifungal susceptibility profile of yeast and filamentous fungi isolated from dermatomycoses in Uberaba, Minas Gerais, Brazil. METHODS: Specimens were obtained from patients with clinically diagnosed and laboratory confirmed dermatomycosis between July 2009 and July 2011. Fungal identification was based on classical methods and antifungal susceptibility testing was performed by broth microdilution method. RESULTS: Of the 216 fungal isolates, 116 (53.8%) were yeasts, 70 (32.4%) dermatophytes and 30 (13.8%) NDFF. Onychomycosis was the most common clinical condition. Candida parapsilosis (24.1%) and Trichophyton rubrum (17.1%) were the fungi most frequently isolated. Voriconazole, ketoconazole and itraconazole were the most potent antifungal agents against yeast, whereas terbinafine, voriconazole and itraconazole had a high in vitro activity against dermatophytes. Overall, the antifungal agents had little or no activity against NDFF and the highest minimum inhibitory concentrations were those against Fusarium spp. CONCLUSION: Yeasts, particularly C. parapsilosis, play an important role as causative agents of dermatomycosis in our region. Our results suggest that the antifungal susceptibility testing coupled with proper identification of the fungi may be useful to assist clinicians in determining the appropriate therapy for dermatomycoses.


Subject(s)
Antifungal Agents/therapeutic use , Dermatomycoses/drug therapy , Fungi/drug effects , Antifungal Agents/pharmacology , Dermatomycoses/microbiology , Fungi/classification , Humans , Microbial Sensitivity Tests
11.
Front Cell Neurosci ; 18: 1340448, 2024.
Article in English | MEDLINE | ID: mdl-38323188

ABSTRACT

Alzheimer's disease (AD), characterized by memory loss and cognitive decline, affects nearly 50 million people worldwide. Amyloid beta (Aß) plaques and intracellular neurofibrillary tangles (NFTs) of phosphorylated Tau protein (pTau) are key histopathological features of the disease in the brain, and recent advances have also identified AD histopathology in the retina. Thus, the retina represents a central nervous system (CNS) tissue highly amenable to non-invasive diagnostic imaging that shows promise as a biomarker for early AD. Given the devastating effects of AD on patients, their families, and society, new treatment modalities that can significantly alter the disease course are urgently needed. In this study, we have developed and characterized a novel human retinal organoid (RO) model derived from induced pluripotent stem cells (iPSCs) from patients with familial AD due to mutations in the amyloid precursor protein gene (APP). Using immunofluorescence and histological staining, we evaluated the cellular composition and AD histopathological features of AD-ROs compared to control ROs from healthy individuals. We found that AD-ROs largely resemble their healthy control counterparts in cellular composition but display increased levels of Aß and pTau. We also present proof of principle of an assay to quantify amyloid levels in whole ROs. This in vitro model of the human AD retina constitutes a new tool for drug screening, biomarker discovery, and pathophysiological studies.

12.
HIV Med ; 14 Suppl 3: 33-7, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24033901

ABSTRACT

OBJECTIVES: The aim of the study was to compare prospectively indicator-condition (IC)-guided testing versus testing of those with non-indicator conditions (NICs) in four primary care centres (PCCs) in Barcelona, Spain. METHODS: From October 2009 to February 2011, patients aged from 18 to 65 years old who attended a PCC for a new herpes zoster infection, seborrhoeic eczema, mononucleosis syndrome or leucopenia/thrombopenia were included in the IC group, and one in every 10 randomly selected patients consulting for other reasons were included in the NIC group. A proportion of patients in each group were offered an HIV test; those who agreed to be tested were given a rapid finger-stick HIV test (€6 per test). Epidemiological and clinical data were collected and analysed. RESULTS: During the study period, 775 patients attended with one of the four selected ICs, while 66,043 patients presented with an NIC. HIV screening was offered to 89 patients with ICs (offer rate 11.5%), of whom 85 agreed to and completed testing (94.4 and 100% acceptance and completion rates, respectively). In the NIC group, an HIV test was offered to 344 persons (offer rate 5.2%), of whom 313 accepted (90.9%) and 304 completed (97.1%) testing. HIV tests were positive in four persons [prevalence 4.7%; 95% confidence interval (CI) 1.3-11.6%] in the IC group and in one person in the NIC group (prevalence 0.3%; 95% CI 0.01-1.82%; P < 0.009). If every eligible person had taken an HIV test, we would have spent €4650 in the IC group and €396,258 in the NIC group, and an estimated 36 (95% CI 25-49) and 198 persons (95% CI 171-227), respectively, would have been diagnosed with HIV infection. The estimated cost per new HIV diagnosis would have been €129 (95% CI €107-153) in the IC group and €2001 (95% CI €1913-2088) in the NIC group. CONCLUSIONS: Although the number of patients included in the study was small and the results should be treated with caution, IC-guided HIV testing, based on four selected ICs, in PCCs seems to be a more feasible and less expensive strategy to improve diagnosis of HIV infection in Spain than a nontargeted HIV testing strategy.


Subject(s)
HIV Infections/diagnosis , Mass Screening/economics , Mass Screening/methods , Adolescent , Adult , Aged , Female , HIV Infections/prevention & control , Humans , Male , Middle Aged , Primary Health Care , Prospective Studies , Spain/epidemiology , Young Adult
13.
Exp Eye Res ; 109: 40-50, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23370269

ABSTRACT

Primary retinal cultures constitute valuable tools not only for basic research on retinal cell development and physiology, but also for the identification of factors or drugs that promote cell survival and differentiation. In order to take full advantage of the benefits of this system it is imperative to develop efficient and reliable techniques for the manipulation of gene expression. However, achieving appropriate transfection efficiencies in these cultures has remained challenging. The purpose of this work was to develop and optimize a technique that would allow the transfection of chick retinal cells with high efficiency and reproducibility for multiple applications. We developed an ex vivo electroporation method applied to dissociated retinal cell cultures that offers a significant improvement over other currently available transfection techniques, increasing efficiency by five-fold. In this method, eyes were enucleated, devoid of RPE, and electroporated with GFP-encoding plasmids using custom-made electrodes. Electroporated retinas were then dissociated into single cells and plated in low density conditions, to be analyzed after 4 days of incubation. Parameters such as voltage and number of electric pulses, as well as plasmid concentration and developmental stage of the animal were optimized for efficiency. The characteristics of the cultures were assessed by morphology and immunocytochemistry, and cell viability was determined by ethidium homodimer staining. Cell imaging and counting was performed using an automated high-throughput system. This procedure resulted in transfection efficiencies in the order of 22-25% of cultured cells, encompassing both photoreceptors and non-photoreceptor neurons, and without affecting normal cell survival and differentiation. Finally, the feasibility of the technique for cell-autonomous studies of gene function in a biologically relevant context was tested by carrying out gain and loss-of-function experiments for the transcription factor PAX6. Electroporation of a plasmid construct expressing PAX6 resulted in a marked upregulation in the expression levels of this protein that could be measured in the whole culture as well as cell-intrinsically. This was accompanied by a significant decrease in the percentage of cells differentiating as photoreceptors among the transfected population. Conversely, electroporation of an RNAi construct targeting PAX6 resulted in a significant decrease in the levels of this protein, with a concomitant increase in the proportion of photoreceptors. Taken together these results provide strong proof-of-principle of the suitability of this technique for genetic studies in retinal cultures. The combination of the high transfection efficiency obtained by this method with automated high-throughput cell analysis supplies the scientific community with a powerful system for performing functional studies in a cell-autonomous manner.


Subject(s)
Electroporation/instrumentation , Electroporation/methods , Retina/cytology , Retina/physiology , Transfection/instrumentation , Transfection/methods , Animals , Cell Count , Chick Embryo , Chickens , Eye Proteins/genetics , Gene Expression Regulation, Developmental/genetics , Green Fluorescent Proteins/genetics , Homeodomain Proteins/genetics , PAX6 Transcription Factor , Paired Box Transcription Factors/genetics , Plasmids/genetics , Plasmids/pharmacokinetics , Primary Cell Culture/methods , Repressor Proteins/genetics
14.
Braz J Microbiol ; 44(1): 253-8, 2013.
Article in English | MEDLINE | ID: mdl-24159312

ABSTRACT

Group B Streptococcus (GBS) is the leading cause of neonatal infections. Our purpose was to characterize GBS colonization in pregnant women, current serotypes, resistance phenotypes and genes associated with virulence. In Misiones, Argentina, there are no previous data on this topic. Vaginal-rectal swabs from 3125 pregnant women were studied between 2004 and 2010. GBS strains were identified by conventional and serological methods (Phadebact Strep B Test, ETC International, Bactus AB, Sweden). Serotypes were detected using Strep-B Latex (Statens Serum Institut, Denmark). Resistance phenotypes were determined by the double-disk test. Genes were studied by PCR. Maternal colonization was 9.38%. Resistance to erythromycin was 11.6%, and the constitutive phenotype was the predominant one. Serotype Ia was the most frequent, whereas serotypes IV, VI, VII and VIII were not detected. The lmb, bca and hylB genes were detected in more than 79% of the strains. In this study, the colonization rate with GBS and the serotype distribution were compared with studies reported in other areas of the country. The high resistance to erythromycin in Misiones justifies performing antibiotic susceptibility testing. The serotype distribution, the genes encoding putative virulence factors, and the patterns of resistance phenotypes of GBS may vary in different areas. They thus need to be evaluated in each place to devise strategies for prevention.

15.
Nanomaterials (Basel) ; 13(19)2023 Oct 06.
Article in English | MEDLINE | ID: mdl-37836355

ABSTRACT

In this work, we report the caloric effect for an electronic system of the antidot type, modeled by combining a repulsive and attractive potential (parabolic confinement). In this system, we consider the action of a perpendicular external magnetic field and the possibility of having an Aharonov-Bohm flux (AB-flux) generated by a current passing through a solenoid placed inside the forbidden zone for the electron. The energy levels are obtained analytically, and the model is known as the Bogachek and Landman model. We propose to control the caloric response of the system by varying only the AB-flux, finding that, in the absence of an external magnetic field, the maximization of the effect always occurs at the same AB-flux intensity, independently of the temperature, while fixing the external magnetic field at a non-zero value breaks this symmetry and changes the point where the caloric phenomenon is maximized and is different depending on the temperature to which the process is carried. Our calculations indicate that using an effective electron mass of GaAs heterostructures and a trap intensity of the order of 2.896 meV, the modification of the AB-flux achieves a variation in temperature of the order of 1 K. Our analysis suggests that increasing the parabolic confinement twofold increases the effect threefold, while increasing the antidot size generates the reverse effect, i.e., a strong decrease in the caloric phenomenon under study. Due to the great diversity in technological applications that have antidots in electronics, the possibility of controlling their thermal response simply by varying the intensity of the internal current inside the solenoid (i.e., the intensity of AB-flux) can be a platform of interest for experimental studies.

16.
J Phys Condens Matter ; 35(32)2023 May 15.
Article in English | MEDLINE | ID: mdl-37146619

ABSTRACT

Core-shell nanoparticles (CSNPs) are a class of functional materials that have received important attention nowadays due to their adjustable properties by a controlled tuning of the core or shell. Understanding the thermal response and structural properties of these CSNPs is relevant to carrying out an analysis regarding their synthesis and application at the nanoscale. The present work is aimed to investigate the shell thickness effect on thermal stability and melting behavior of Al@Fe CSNPs by using molecular dynamics simulations. The results are discussed considering the influence of the Fe shell on the Al nanoparticle and analyzing the effect of different shell thicknesses in Al@Fe CSNPs. In general, calorific curves show a smooth energy decline for temperatures greater than room temperature for different shell thicknesses and sizes, corresponding to the inward and outward atomic movement of Al and Fe atoms, respectively, that produce a mixed Al-Fe nanoalloy. Here, the thermal stability of the Al@Fe nanoparticle is gradually lost passing to a liquid-Al@solid-Fe configuration and reaching a mixed Al-Fe state by an exothermic mechanism. Combining quantities of the atomic diffusion and structural identification, a stepped structural transition of the system is subsequently observed, where the melting-like point was estimated. Furthermore, it is observed that the Al@Fe CSNPs with greater stability are obtained with a thick shell and a large size. The ability to control shell thickness and vary the size opens up attractive opportunities to synthesize a broad range of new materials with tunable catalytic properties.

17.
Reprod Domest Anim ; 47(3): e39-42, 2012 Jun.
Article in English | MEDLINE | ID: mdl-21988522

ABSTRACT

The development of dominant follicles requires the parallel growth of a vascular network, regulated by VEGF and its receptors VEGFR-1 and VEGFR-2. Here, we demonstrate the presence of mRNA for the soluble forms of VEGFR-1 and VEGFR-2 by RT-PCR and the respective proteins by Western blot, in bovine dominant follicles. The 3' end of the mRNA coding region and the deduced C-terminal amino acid sequence of the bovine VEGFR soluble forms were similar to those previously described in human and mice. The relative abundance of sVEGFR-1 was higher in dominant follicles of day 4, decreasing on day 6 and further on day 9 of the cycle. In contrast, sVEGFR-2 expression was low on day 4 follicles and increased as the cycle advanced, becoming greater on day 9. The changes of sVEGFR-1 and sVEGFR-2 with the age of the bovine dominant follicle indicate a physiological role in its growth and atresia.


Subject(s)
Gene Expression Regulation/physiology , Ovarian Follicle/metabolism , Vascular Endothelial Growth Factor Receptor-1/metabolism , Vascular Endothelial Growth Factor Receptor-2/metabolism , Amino Acid Sequence , Animals , Base Sequence , Cattle , Estrous Cycle/physiology , Female , Molecular Sequence Annotation , RNA, Messenger/genetics , RNA, Messenger/metabolism , Vascular Endothelial Growth Factor Receptor-1/genetics , Vascular Endothelial Growth Factor Receptor-2/genetics
18.
J Fish Biol ; 81(5): 1686-95, 2012 Oct.
Article in English | MEDLINE | ID: mdl-23020568

ABSTRACT

The trophic interactions between the scyphozoan medusa Chrysaora plocamia and the palm ruff Seriolella violacea were investigated off northern Chile and showed that large numbers of hyperiid amphipods parasitizing the medusa may channel energy back to the fishes, which feed on the parasites. The biomass of hyperiids eaten by the fish was a function of the biomass of hyperiids parasitizing the medusa. This temporally available food supply may enhance fish recruitment. The large number of hyperiids parasitizing diverse jellyfish species represents a missing trophic link in current efforts to understand the effects of jellyfish blooms on marine food webs.


Subject(s)
Amphipoda/physiology , Food Chain , Perciformes/physiology , Scyphozoa/parasitology , Animals , Biomass , Diet
19.
Transl Res ; 250: 98-111, 2022 12.
Article in English | MEDLINE | ID: mdl-35690342

ABSTRACT

The ability to generate human retinas in vitro from pluripotent stem cells opened unprecedented opportunities for basic science and for the development of therapeutic approaches for retinal degenerative diseases. Retinal organoid models not only mimic the histoarchitecture and cellular composition of the native retina, but they can achieve a remarkable level of maturation that allows them to respond to light stimulation. However, studies evaluating the nature, magnitude, and properties of light-evoked responsivity from each cell type, in each retinal organoid layer, have been sparse. In this review we discuss the current understanding of retinal organoid function, the technologies used for functional assessment in human retinal organoids, and the challenges and opportunities that lie ahead.


Subject(s)
Organoids , Pluripotent Stem Cells , Humans , Retina/metabolism , Cell Differentiation
20.
Rev Esp Anestesiol Reanim (Engl Ed) ; 69(10): 663-673, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36241514

ABSTRACT

INTRODUCTION: Rapid sequence intubation is an airway rescue and protection technique in which different sedatives are used to perform orotracheal intubation. Etomidate, due to its pharmacokinetic and pharmacodynamic qualities, particularly hemodynamic stability, is the most widely used sedative in this scenario. However, its superiority over other sedatives is controversial. MATERIALS AND METHODS: We performed a meta-analysis using a pre-designed protocol and PRISMA guidelines to evaluate the mean difference between systolic blood pressure before and after administration of the sedative. We also analyzed the relative risks of hypotension. RESULTS: Ten studies were included. The incidence of hypotension in patients receiving etomidate ranged from 6.4% to 75.2%, and between 24.0% and 65.9% in patients receiving other sedatives. No significant differences were found in the mean difference in systolic blood pressure during pre-intubation 0.01 mm Hg (95% CI: -0.90; 0.92) or in post-intubation 0.98 mmHg (95% CI: -0.24; 2.20). The relative risk analysis showed that the risk of hypotension is equal to an RR of 1.19 (95% CI: 0.92-1.54) between those who received etomidate and those who received the other sedatives. CONCLUSIONS: The risk of hypotension after rapid intubation sequence with etomidate does not differ significantly compared to other sedatives. However, the studies included in this review were heterogeneous.


Subject(s)
Etomidate , Hypotension , Humans , Etomidate/adverse effects , Hypnotics and Sedatives/adverse effects , Rapid Sequence Induction and Intubation , Intubation, Intratracheal/methods , Hypotension/chemically induced
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