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1.
Trends Biochem Sci ; 49(4): 280-282, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38233283

RESUMEN

Recent advances in cryo-electron microscopy (Cryo-EM) have revolutionized our understanding of the complement C5a/C3a receptors that are crucial in inflammation. A recent report by Yadav et al. has elucidated the activation, ligand binding, selectivity, and signaling bias of these receptors, thereby enhancing structure-guided drug discovery. This paves the way for more effective anti-inflammatory therapies that target these receptors with unprecedented precision.


Asunto(s)
Anafilatoxinas , Complemento C5a , Anafilatoxinas/química , Anafilatoxinas/metabolismo , Complemento C5a/metabolismo , Complemento C3a/metabolismo , Microscopía por Crioelectrón , Receptores de Complemento/metabolismo
2.
Adv Exp Med Biol ; 3234: 73-88, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38507201

RESUMEN

The specific kinetics and thermodynamics of protein-protein interactions underlie the molecular mechanisms of cellular functions; hence the characterization of these interaction parameters is central to the quantitative understanding of physiological and pathological processes. Many methods have been developed to study protein-protein interactions, which differ in various features including the interaction detection principle, the sensitivity, whether the method operates in vivo, in vitro, or in silico, the temperature control, the use of labels, immobilization, the amount of sample required, the number of measurements that can be accomplished simultaneously, or the cost. Bio-Layer Interferometry (BLI) is a label-free biophysical method to measure the kinetics of protein-protein interactions. Label-free interaction assays are a broad family of methods that do not require protein modifications (other than immobilization) or labels such as fusions with fluorescent proteins or transactivating domains or chemical modifications like biotinylation or reaction with radionuclides. Besides BLI, other label-free techniques that are widely used for determining protein-protein interactions include surface plasmon resonance (SPR), thermophoresis, and isothermal titration calorimetry (ITC), among others.


Asunto(s)
Proteínas , Resonancia por Plasmón de Superficie , Unión Proteica , Termodinámica , Proteínas/química , Interferometría/métodos , Cinética
3.
Adv Exp Med Biol ; 3234: 125-140, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38507204

RESUMEN

X-ray crystallography has for most of the last century been the standard technique to determine the high-resolution structure of biological macromolecules, including multi-subunit protein-protein and protein-nucleic acids as large as the ribosome and viruses. As such, the successful application of X-ray crystallography to many biological problems revolutionized biology and biomedicine by solving the structures of small molecules and vitamins, peptides and proteins, DNA and RNA molecules, and many complexes-affording a detailed knowledge of the structures that clarified biological and chemical mechanisms, conformational changes, interactions, catalysis and the biological processes underlying DNA replication, translation, and protein synthesis. Now reaching well into the first quarter of the twenty-first century, X-ray crystallography shares the structural biology stage with cryo-electron microscopy and other innovative structure determination methods, as relevant and central to our understanding of biological function and structure as ever. In this chapter, we provide an overview of modern X-ray crystallography and how it interfaces with other mainstream structural biology techniques, with an emphasis on macromolecular complexes.


Asunto(s)
Biología Molecular , Proteínas , Cristalografía por Rayos X , Microscopía por Crioelectrón/métodos , Proteínas/química , Sustancias Macromoleculares/química
4.
Pharmacol Res ; 197: 106948, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37806602

RESUMEN

The most recent and promising therapeutic strategies for inflammatory bowel disease (IBD) have engaged biologics targeting single effector components involved in major steps of the immune-inflammatory processes, such as tumor necrosis factor, interleukins or integrins. Nevertheless, these molecules have not yet met expectations regarding efficacy and safety, resulting in a significant percentage of refractory or relapsing patients. Thus, novel treatment options are urgently needed. The minor isoform of the complement inhibitor C4b-binding protein, C4BP(ß-), has been shown to confer a robust anti-inflammatory and immunomodulatory phenotype over inflammatory myeloid cells. Here we show that C4BP(ß-)-mediated immunomodulation can significantly attenuate the histopathological traits and preserve the intestinal epithelial integrity in dextran sulfate sodium (DSS)-induced murine colitis. C4BP(ß-) downregulated inflammatory transcripts, notably those related to neutrophil activity, mitigated circulating inflammatory effector cytokines and chemokines such as CXCL13, key in generating ectopic lymphoid structures, and, overall, prevented inflammatory immune cell infiltration in the colon of colitic mice. PRP6-HO7, a recombinant curtailed analogue with only immunomodulatory activity, achieved a similar outcome as C4BP(ß-), indicating that the therapeutic effect is not due to the complement inhibitory activity. Furthermore, both C4BP(ß-) and PRP6-HO7 significantly reduced, with comparable efficacy, the intrinsic and TLR-induced inflammatory markers in myeloid cells from both ulcerative colitis and Crohn's disease patients, regardless of their medication. Thus, the pleiotropic anti-inflammatory and immunomodulatory activity of PRP6-HO7, able to "reprogram" myeloid cells from the complex inflammatory bowel environment and to restore immune homeostasis, might constitute a promising therapeutic option for IBD.


Asunto(s)
Colitis , Enfermedades Inflamatorias del Intestino , Animales , Humanos , Ratones , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Inmunomodulación , Inflamación , Enfermedades Inflamatorias del Intestino/inducido químicamente , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Células Mieloides
5.
Ann Hematol ; 101(10): 2263-2270, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35997804

RESUMEN

Failure of second-generation tyrosine kinase inhibitors (2GTKI) is a challenging situation in patients with chronic myeloid leukemia (CML). Asciminib, recently approved by the US Federal Drug Administration, has demonstrated in clinical trials a good efficacy and safety profile after failure of 2GTKI. However, no study has specifically addressed response rates to asciminib in ponatinib pretreated patients (PPT). Here, we present data on responses to asciminib from 52 patients in clinical practice, 20 of them (38%) with prior ponatinib exposure. We analyzed retrospectively responses and toxicities under asciminib and compared results between PPT and non-PPT patients.After a median follow-up of 30 months, 34 patients (65%) switched to asciminib due to intolerance and 18 (35%) due to resistance to prior TKIs. Forty-six patients (88%) had received at least 3 prior TKIs. Regarding responses, complete cytogenetic response was achieved or maintained in 74% and 53% for non-PPT and PPT patients, respectively. Deeper responses such as major molecular response and molecular response 4.5 were achieved in 65% and 19% in non-PPT versus 32% and 11% in PPT, respectively. Two patients (4%) harbored the T315I mutation, both PPT.In terms of toxicities, non-PPT displayed 22% grade 3-4 TEAE versus 20% in PPT. Four patients (20% of PPT) suffered from cross-intolerance with asciminib as they did under ponatinib.Our data supports asciminib as a promising alternative in resistant and intolerant non-PPT patients, as well as in intolerant PPT patients; the resistant PPT subset remains as a challenging group in need of further therapeutic options.


Asunto(s)
Antineoplásicos , Leucemia Mielógena Crónica BCR-ABL Positiva , Piridazinas , Antineoplásicos/efectos adversos , Resistencia a Antineoplásicos , Proteínas de Fusión bcr-abl/genética , Humanos , Imidazoles , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Niacinamida/análogos & derivados , Inhibidores de Proteínas Quinasas/efectos adversos , Pirazoles , Piridazinas/efectos adversos , Estudios Retrospectivos
6.
Semin Cell Dev Biol ; 85: 98-109, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29221973

RESUMEN

The surveillance and pathogen fighting functions of the complement system have evolved to protect mammals from life-threatening infections. In turn, pathogens have developed complex molecular mechanisms to subvert, divert and evade the effector functions of the complement. The study of complement immunoevasion by pathogens sheds light on their infection drivers, knowledge that is essential to implement therapies. At the same time, complement evasion also acts as a discovery ground that reveals important aspects of how complement works under physiological conditions. In recent years, complex interrelationships between infection insults and the onset of autoimmune and complement dysregulation diseases have led to propose that encounters with pathogens can act as triggering factors for disease. The correct management of these diseases involves the recognition of their triggering factors and the development and administration of complement-associated molecular therapies. Even more recently, unsuspected proteins from pathogens have been shown to possess moonlighting functions as virulence factors, raising the possibility that behind the first line of virulence factors there be many more pathogen proteins playing secondary, helping and supporting roles for the pathogen to successfully establish infections. In an era where antibiotics have a progressively reduced effect on the management and control of infectious diseases worldwide, knowledge on the mechanisms of pathogenic invasion and evasion look more necessary and pressing than ever.


Asunto(s)
Proteínas del Sistema Complemento/inmunología , Interacciones Huésped-Patógeno/inmunología , Enfermedad , Humanos
7.
Neurobiol Learn Mem ; 179: 107409, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33609738

RESUMEN

Ghrelin (Gr) is an orexigenic peptide that acts via its specific receptor, GHSR-1a distributed throughout the brain, being mainly enriched in pituitary, cortex and hippocampus (Hp) modulating a variety of brain functions. Behavioral, electrophysiological and biochemical evidence indicated that Gr modulates the excitability and the synaptic plasticity in Hp. The present experiments were designed in order to extend the knowledge about the Gr effect upon structural synaptic plasticity since morphological and quantitative changes in spine density after Gr administration were analyzed "in vitro" and "in vivo". The results show that Gr administered to hippocampal cultures or stereotactically injected in vivo to Thy-1 mice increases the density of dendritic spines (DS) being the mushroom type highly increased in secondary and tertiary extensions. Spines classified as thin type were increased particularly in primary extensions. Furthermore, we show that Gr enhances selectively the expression of BDNF-mRNA species.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/efectos de los fármacos , Ghrelina/farmacología , Hipocampo/efectos de los fármacos , Plasticidad Neuronal/efectos de los fármacos , Células Piramidales/efectos de los fármacos , ARN Mensajero/efectos de los fármacos , Animales , Factor Neurotrófico Derivado del Encéfalo/genética , Espinas Dendríticas/efectos de los fármacos , Espinas Dendríticas/patología , Hipocampo/citología , Hipocampo/metabolismo , Microscopía Confocal , Neuronas/citología , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Células Piramidales/metabolismo , Células Piramidales/patología , ARN Mensajero/metabolismo , Ratas
8.
Rheumatol Int ; 41(10): 1869-1874, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32642830

RESUMEN

Alkaptonuria is a rare autosomal-recessive disorder that produces accumulation of homogentisic acid in body fluids. The accumulation in collagen tissues, mainly in the joint cartilage, produces ochronotic arthropathy. We report two clinical cases of one brother and sister with alkaptonuria and ochronotic arthropathy diagnosed in old age. In the first case, the patient is diagnosed by musculoskeletal involvement with long-term low back pain with other associated manifestations that made this pathology suspected. In the second case, the patient comes due to osteoporosis and other associated fractures and with the family history and the rest of the clinic, the appropriate complementary tests were performed and the diagnosis is established. It is unknown if there is consanguinity in these patients between parents or ancestors. It is an infrequent pathology that is often diagnosed intraoperatively. Despite the poor efficacy of medical treatment, it would be advisable to make an early diagnosis to avoid accumulation of the pigment and accelerated joint destruction and deposition in other locations. Owing to its prevalence, it is difficult to find a significant number of patients to search for new treatments that are intended to correct the enzyme deficit and not only to modify the elimination.


Asunto(s)
Alcaptonuria/diagnóstico , Ocronosis/diagnóstico , Anciano , Cartílago Articular/patología , Femenino , Humanos , Artropatías/diagnóstico por imagen , Artropatías/fisiopatología , Dolor de la Región Lumbar/etiología , Masculino , Osteoporosis/complicaciones , Hermanos
9.
Int J Mol Sci ; 22(20)2021 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-34681942

RESUMEN

Endoglin (Eng, CD105) is a type I membrane glycoprotein that functions in endothelial cells as an auxiliary receptor for transforming growth factor ß (TGF-ß)/bone morphogenetic protein (BMP) family members and as an integrin ligand, modulating the vascular pathophysiology. Besides the membrane-bound endoglin, there is a soluble form of endoglin (sEng) that can be generated by the action of the matrix metalloproteinase (MMP)-14 or -12 on the juxtamembrane region of its ectodomain. High levels of sEng have been reported in patients with preeclampsia, hypercholesterolemia, atherosclerosis and cancer. In addition, sEng is a marker of cardiovascular damage in patients with hypertension and diabetes, plays a pathogenic role in preeclampsia, and inhibits angiogenesis and tumor proliferation, migration, and invasion in cancer. However, the mechanisms of action of sEng have not yet been elucidated, and new tools and experimental approaches are necessary to advance in this field. To this end, we aimed to obtain a fluorescent form of sEng as a new tool for biological imaging. Thus, we cloned the extracellular domain of endoglin in the pEGFP-N1 plasmid to generate a fusion protein with green fluorescent protein (GFP), giving rise to pEGFP-N1/Eng.EC. The recombinant fusion protein was characterized by transient and stable transfections in CHO-K1 cells using fluorescence microscopy, SDS-PAGE, immunodetection, and ELISA techniques. Upon transfection with pEGFP-N1/Eng.EC, fluorescence was readily detected in cells, indicating that the GFP contained in the recombinant protein was properly folded into the cytosol. Furthermore, as evidenced by Western blot analysis, the secreted fusion protein yielded the expected molecular mass and displayed a specific fluorescent signal. The fusion protein was also able to bind to BMP9 and BMP10 in vitro. Therefore, the construct described here could be used as a tool for functional in vitro studies of the extracellular domain of endoglin.


Asunto(s)
Proteínas Morfogenéticas Óseas/metabolismo , Endoglina/metabolismo , Proteínas Fluorescentes Verdes/metabolismo , Factor 2 de Diferenciación de Crecimiento/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Animales , Células CHO , Cricetulus , Endoglina/genética , Proteínas Fluorescentes Verdes/genética , Humanos , Proteínas Recombinantes de Fusión/genética
10.
J Appl Microbiol ; 128(5): 1248-1260, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31566847

RESUMEN

Lactic acid bacteria (LAB) are widely distributed in nature and, due to their beneficial effects on the host, are used as probiotics. This review describes the applications of LAB in animal production systems such as beekeeping, poultry, swine and bovine production, particularly as probiotics used to improve health, enhance growth and reproductive performance. Given the importance of honeybees in nature and the beekeeping industry as a producer of healthy food worldwide, the focus of this review is on the coexistence of LAB with honeybees, their food and environment. The main LAB species isolated from the beehive and their potential technological use are described. Evidence is provided that 43 LAB bacteria species have been isolated from beehives, of which 20 showed inhibition against 28 species of human and animal pathogens, some of which are resistant to antibiotics. Additionally, the presence of LAB in the beehive and their relationship with antibacterial properties of honey and pollen is discussed. Finally, we describe the use of lactic bacteria from bee colonies and their antimicrobial effect against foodborne pathogens and human health. This review broadens knowledge by highlighting the importance of honeybee colonies as suppliers of LAB and functional food.


Asunto(s)
Abejas/microbiología , Lactobacillales/aislamiento & purificación , Lactobacillales/metabolismo , Animales , Antibacterianos/metabolismo , Antibacterianos/farmacología , Industria de Alimentos , Alimentos Funcionales , Miel , Humanos , Lactobacillales/clasificación , Polen , Probióticos
11.
Neurol Sci ; 41(8): 2207-2213, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32172402

RESUMEN

INTRODUCTION: Stigma manifests both in prejudices and rejection from society towards patients who suffer from a specific pathology, and by patient's internalization of this discrimination, with the consequent repercussions on their state of mind and quality of life. The aim of the study was to quantify the stigma associated with migraine and analyze whether it is related to the clinical-demographic characteristics of the patients, as well as the possible impact on their daily lives. MATERIALS AND METHODS: The stigma scale for chronic illness (SSCI) and other questionnaires were administered to 56 patients with episodic migraine (EM), 18 with chronic migraine (CM), and 21 with epilepsy, as a control group. RESULTS: The mean SSCI score was higher (51.6 ± 15.0) in the CM group than in the EM (45.0 ± 13.5) and epilepsy (47.6 ± 15.5) groups, without reaching statistical significance. In addition, the score was higher in patients who were unemployed, divorced, and in those who had migraine with aura. A statistically significant correlation was found between the SSCI score and the impact of migraine on daily life, the presence of stress, anxiety and depression, and low self-esteem. CONCLUSIONS: There is a stigma around migraine in our society, which seems to be more prevalent in patients with certain socio-demographic characteristics, and that is related to stress, mood alterations, and low self-esteem. Trying to reduce stigma could contribute to improve the control of migraine and reduce the impact of the disease at a socio-economic level.


Asunto(s)
Trastornos Migrañosos , Calidad de Vida , Ansiedad , Humanos , Trastornos Migrañosos/epidemiología , Estigma Social , Encuestas y Cuestionarios
12.
Rheumatol Int ; 40(8): 1327-1332, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32533290

RESUMEN

Crystalglobulinemia is an extremely rare pathology that is associated in most cases with plasma cell dyscrasia, mainly multiple myeloma. In most cases, it may be the manifestation of incipient gammopathy or it manifests shortly after diagnosis. We report a patient with ischemic lesions of thrombotic origin in lower limbs. Subsequently, renal involvement occurs, in view of this involvement, it is suspected that the patient may have an associated vasculitis. After performing the biopsy and with the subsequent diagnosis of monoclonal gammopathy of uncertain significance, the diagnosis is made. We review the most recent bibliography of patients who have been diagnosed with crystalglobulinemia associated with plasma dyscrasia focusing in those with thrombotic vasculopathy or acute renal failure. In our case, in addition to being associated with monoclonal gammopathy of undetermined significance that is less frequent, the debut of the symptoms is years before the detection of the monoclonal peak. This could speak of patients with a low peak of monoclonal component (not detected by immunoelectrophoresis) who could have kidney and vascular damage.


Asunto(s)
Paraproteinemias/diagnóstico , Lesión Renal Aguda/etiología , Lesión Renal Aguda/cirugía , Adulto , Diagnóstico Tardío , Femenino , Humanos , Trasplante de Riñón , Gammopatía Monoclonal de Relevancia Indeterminada/diagnóstico , Mieloma Múltiple/complicaciones , Paraproteinemias/complicaciones , Paraproteinemias/fisiopatología , Microangiopatías Trombóticas/patología
13.
J Assist Reprod Genet ; 37(7): 1567-1577, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32594284

RESUMEN

PURPOSE: The state of limited resource settings that Coronavirus (COVID-19) pandemic has created globally should be taken seriously into account especially in healthcare sector. In oncofertility, patients should receive their fertility preservation treatments urgently even in limited resource settings before initiation of anticancer therapy. Therefore, it is very crucial to learn more about oncofertility practice in limited resource settings such as in developing countries that suffer often from shortage of healthcare services provided to young patients with cancer. METHODS: As an extrapolation during the global crisis of COVID-19 pandemic, we surveyed oncofertility centers from 14 developing countries (Egypt, Tunisia, Brazil, Peru, Panama, Mexico, Colombia, Guatemala, Argentina, Chile, Nigeria, South Africa, Saudi Arabia, and India). Survey questionnaire included questions on the availability and degree of utilization of fertility preservation options in case of childhood cancer, breast cancer, and blood cancer. RESULTS: All surveyed centers responded to all questions. Responses and their calculated oncofertility scores showed different domestic standards for oncofertility practice in case of childhood cancer, breast cancer, and blood cancer in the developing countries under limited resource settings. CONCLUSIONS: Medical practice in limited resource settings has become a critical topic especially after the global crisis of COVID-19 pandemic. Understanding the resources necessary to provide oncofertility treatments is important until the current COVID-19 pandemic resolves. Lessons learned will be valuable to future potential worldwide disruptions due to infectious diseases or other global crises.


Asunto(s)
Betacoronavirus/patogenicidad , Infecciones por Coronavirus/prevención & control , Atención a la Salud/normas , Preservación de la Fertilidad/métodos , Neoplasias/terapia , Pandemias/prevención & control , Neumonía Viral/prevención & control , Betacoronavirus/aislamiento & purificación , COVID-19 , Infecciones por Coronavirus/transmisión , Infecciones por Coronavirus/virología , Atención a la Salud/economía , Países en Desarrollo , Femenino , Preservación de la Fertilidad/economía , Preservación de la Fertilidad/estadística & datos numéricos , Humanos , Neoplasias/virología , Neumonía Viral/transmisión , Neumonía Viral/virología , SARS-CoV-2 , Encuestas y Cuestionarios
14.
Allergol Immunopathol (Madr) ; 47(3): 282-288, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30595390

RESUMEN

OBJECTIVE: To describe potential regional variations in therapies for severe asthma exacerbations in Chilean children and estimate the associated health expenditures. METHODS: Observational prospective cohort study in 14 hospitals over a one-year period. Children five years of age or older were eligible for inclusion. Days with oxygen supply and pharmacological treatments received were recorded from the clinical chart. A basic asthma hospitalization basket was defined in order to estimate the average hospitalization cost for a single patient. Six months after discharge, new visits to the Emergency Room (ER), use of systemic corticosteroids and adherence to the controller treatment were evaluated. RESULTS: 396 patients were enrolled. Patients from the public health system and from the north zone received significantly more days of oxygen, systemic corticosteroids and antibiotics. Great heterogeneity in antibiotic use among the participating hospitals was found, from 0 to 92.3% (ICC 0.34, 95% CI 0.16-0.52). The use of aminophylline, magnesium sulfate and ketamine varied from 0 to 36.4% between the different Pediatric Intensive Care Units (ICC 0.353, 95% CI 0.010-0.608). The average cost per inpatient was of $1910 USD. 290 patients (73.2%) completed the follow-up six months after discharge. 76 patients (26.2%) were not receiving any controller treatment and nearly a fourth had new ER visits and use of systemic corticosteroids due to new asthma exacerbations. CONCLUSIONS: Considerable practice variation in asthma exacerbations treatment was found among the participating hospitals, highlighting the poor outcome of many patients after hospital discharge, with an important health cost.


Asunto(s)
Corticoesteroides/uso terapéutico , Asma/epidemiología , Costo de Enfermedad , Asma/tratamiento farmacológico , Asma/economía , Niño , Chile/epidemiología , Estudios de Cohortes , Progresión de la Enfermedad , Servicios Médicos de Urgencia , Femenino , Estudios de Seguimiento , Hospitalización , Humanos , Masculino , Estudios Prospectivos , Resultado del Tratamiento
15.
Mol Phylogenet Evol ; 127: 867-877, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29958981

RESUMEN

Osgoodomys banderanus is a recognized and endemic rodent species of western Mexico, an area known for its high biodiversity and number of endemisms. Phylogeographical relationships within this taxon were analyzed based on mitochondrial (ND3, tRNA-Arginine, ND4L and partial ND4) and nuclear (GHR) nucleotide sequences. We obtained a total of 112 samples from 22 localities, covering the complete distribution of the species. Phylogenetic analyses using Maximum Likelihood and Bayesian inference confirmed that Osgoodomys is a monophyletic group. In addition, phylogenetic and phylogeographic analyses detected three major clades, which do not coincide with the recognized subspecies of O. banderanus. The genetic lineages detected are the western clade (Nayarit, Jalisco and northern Colima), the central clade (Colima, Michoacán, and northern Guerrero) and the eastern clade (central and southern Guerrero). Genetic distances among clades (5-9%) and nucleotide substitutions (30-88) among haplogroups were high, especially in the southern group. Mountain ranges such as the Transmexican Volcanic Belt and the Sierra Madre del Sur, as well as the Balsas River act as geographical barriers for Osgoodomys. Our results suggest the presence of three independent species, which need to be characterized morphologically to confirm our hypothesis.


Asunto(s)
Arvicolinae/clasificación , Arvicolinae/genética , Ecosistema , Filogeografía , Animales , Secuencia de Bases , Teorema de Bayes , Biodiversidad , ADN Mitocondrial/genética , Variación Genética , Geografía , Haplotipos/genética , México , Filogenia , Factores de Tiempo
16.
Phys Rev Lett ; 121(3): 036402, 2018 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-30085784

RESUMEN

We study the low-frequency dynamics of periodically driven one-dimensional systems hosting Floquet topological phases. We show, both analytically and numerically, in the low frequency limit Ω→0, the topological invariants of a chirally symmetric driven system exhibit universal fluctuations. While the topological invariants in this limit nearly vanish on average over a small range of frequencies, we find that they follow a universal Gaussian distribution with a width that scales as 1/sqrt[Ω]. We explain this scaling based on a diffusive structure of the winding numbers of the Floquet-Bloch evolution operator at low frequency. We also find that the maximum quasienergy gap remains finite and scales as Ω^{2}. Thus, we argue that the adiabatic limit of a Floquet topological insulator is highly structured, with universal fluctuations persisting down to very low frequencies.

17.
Arch Biochem Biophys ; 660: 36-52, 2018 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-30342013

RESUMEN

Pain is a prevalent complex medical problem, characterized by physically debilitating and mentally destabilizing conditions. Current pain therapeutics mainly include non-steroidal anti-inflammatory drugs and narcotics (opioids), but they exhibit limitations in efficacy, unwanted side effects and the problem of drug abuse. To overcome these issues, the discovery of different molecular players within pain pathways could lead to new opportunities for therapeutic intervention. Among other strategies, peptides could be powerful pharmaceutical agents for effective opioid-free medications for pain treatment. This review is a compendium of representative non-opioid analgesic peptides acting directly or indirectly at different ion channels and receptors distributed in nociceptive pathways. They include peptides targeting Ca2+, Na+ and K+ voltage-gated ion channels, the neuronal nicotinic receptors (nAChR), transient receptor potential channels (TRP), and different non-opioid G-protein coupled receptors (GPCRs), like the calcitonin gen-related peptide (CGRP), cannabinoid, bradykinin and neurotensin receptors, among others. Peptides engineered from protein-protein interactions among pain-related receptors and regulatory proteins also led to new therapeutic approaches for pain management. Following some successful examples, already in the clinics or under clinical trials, the improved understanding of pain mechanisms, and the advances in peptide permeation and/or delivery, could afford new analgesic peptides in the near future.


Asunto(s)
Analgésicos no Narcóticos/farmacología , Animales , Humanos , Canales Iónicos/metabolismo , Terapia Molecular Dirigida , Receptores Acoplados a Proteínas G/metabolismo
18.
Clin Rehabil ; 32(9): 1220-1234, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29651873

RESUMEN

OBJECTIVE: To evaluate the evidence for the use of virtual reality to treat balance and gait impairments in multiple sclerosis rehabilitation. DESIGN: Systematic review and meta-analysis of randomized controlled trials and quasi-randomized clinical trials. METHODS: An electronic search was conducted using the following databases: MEDLINE (PubMed), Physiotherapy Evidence Database (PEDro), Cochrane Database of Systematic Reviews (CDSR) and (CINHAL). A quality assessment was performed using the PEDro scale. The data were pooled and a meta-analysis was completed. This systematic review was conducted in accordance with the (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) PRISMA guideline statement. It was registered in the PROSPERO database (CRD42016049360). RESULTS: A total of 11 studies were included. The data were pooled, allowing meta-analysis of seven outcomes of interest. A total of 466 participants clinically diagnosed with multiple sclerosis were analysed. Results showed that virtual reality balance training is more effective than no intervention for postural control improvement (standard mean difference (SMD) = -0.64; 95% confidence interval (CI) = -1.05, -0.24; P = 0.002). However, significant overall effect was not showed when compared with conventional training (SMD = -0.04; 95% CI = -0.70, 0.62; P = 0.90). Inconclusive results were also observed for gait rehabilitation. CONCLUSION: Virtual reality training could be considered at least as effective as conventional training and more effective than no intervention to treat balance and gait impairments in multiple sclerosis rehabilitation.


Asunto(s)
Trastornos Neurológicos de la Marcha/rehabilitación , Esclerosis Múltiple/rehabilitación , Modalidades de Fisioterapia , Equilibrio Postural/fisiología , Juegos de Video , Realidad Virtual , Trastornos Neurológicos de la Marcha/fisiopatología , Humanos , Esclerosis Múltiple/fisiopatología
19.
Allergol Immunopathol (Madr) ; 46(6): 533-538, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29720350

RESUMEN

BACKGROUND: Asthma hospitalization rates in Chilean children have increased in the last 14 years, but little is known about the factors associated with this. OBJECTIVE: Describe clinical characteristics of children hospitalized for asthma exacerbation. METHODS: Observational prospective cohort study in 14 hospitals. Over a one-year period, children five years of age or older hospitalized with asthma exacerbation were eligible for inclusion. Parents completed an online questionnaire with questions on demographic information, about asthma, indoor environmental contaminant exposure, comorbidities and beliefs about disease and treatment. Disease control was assessed by the Asthma Control Test. Inhalation technique was observed using a checklist. RESULTS: 396 patients were enrolled. 168 children did not have an established diagnosis of asthma. Only 188 used at least one controller treatment at the time of hospitalization. 208 parents said they believed their child had asthma only when they had an exacerbation and 97 correctly identified inhaled corticosteroids as anti-inflammatory treatment. 342 patients used the wrong spacer and 73 correctly performed all steps of the checklist. CONCLUSIONS: Almost half of the patients were not diagnosed with asthma at the time of hospitalization despite having a medical history suggestive of the disease. In the remaining patients with an established diagnosis of asthma potentially modifiable factors like bad adherence to treatment and poor inhalation technique were found. Implementing a nationwide asthma program including continued medical education for the correct diagnosis and follow up of these patients and asthma education for patients and caregivers is needed to reduce asthma hospitalization rates in Chilean children.


Asunto(s)
Asma/epidemiología , Hospitalización/estadística & datos numéricos , Educación del Paciente como Asunto , Corticoesteroides/uso terapéutico , Asma/terapia , Cuidadores , Niño , Chile/epidemiología , Estudios de Cohortes , Progresión de la Enfermedad , Educación Médica Continua , Femenino , Humanos , Masculino , Cooperación del Paciente , Estudios Prospectivos
20.
Allergol Immunopathol (Madr) ; 46(3): 291-303, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29288048

RESUMEN

BACKGROUND: With the availability of high-quality asthma guidelines worldwide, one possible approach of developing a valid guideline, without re-working the evidence, already analysed by major guidelines, is the ADAPTE approach, as was used for the development of National Guidelines on asthma. METHODS: The guidelines development group (GDG) covered a broad range of experts from medical specialities, primary care physicians and methodologists. The core group of the GDG searched the literature for asthma guidelines 2005 onward, and analysed the 11 best guidelines with AGREE-II to select three mother guidelines. Key clinical questions were formulated covering each step of the asthma management. RESULTS: The selected mother guidelines are British Thoracic Society (BTS), GINA and GEMA 2015. Responses to the questions were formulated according to the evidence in the mother guidelines. Recommendations or suggestions were made for asthma treatment in Mexico by the core group, and adjusted during several rounds of a Delphi process, taking into account: 1. Evidence; 2. Safety; 3. Cost; 4. Patient preference - all these set against the background of the local reality. Here the detailed analysis of the evidence present in BTS/GINA/GEMA sections on prevention and diagnosis in paediatric asthma are presented for three age-groups: children with asthma ≤5 years, 6-11 years and ≥12 years. CONCLUSIONS: For the prevention and diagnosis sections, applying the AGREE-II method is useful to develop a scientifically-sustained document, adjusted to the local reality per country, as is the Mexican Guideline on Asthma.


Asunto(s)
Asma/diagnóstico , Asma/prevención & control , Niño , Preescolar , Femenino , Humanos , Masculino , México
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