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1.
Biol Reprod ; 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38832705

RESUMEN

Following blastocyst hatching, ungulate embryos undergo a prolonged preimplantation period termed conceptus elongation. Conceptus elongation constitutes a highly susceptible period for embryonic loss and the embryonic requirements during this process are largely unknown, but multiple lipid compounds have been identified in the fluid nourishing the elongating conceptuses. Peroxisome proliferator-activated receptors (PPARs) mediate the signaling actions of prostaglandins and other lipids and, between them, PPARG has been pointed out to play a relevant role on conceptus elongation by a functional study that depleted PPARG in both uterus and conceptus. The objective of this study has been to determine if embryonic PPARG is required for bovine embryo development. To that aim, we have generated bovine PPARG KO embryos in vitro by two independent gene ablation strategies and assess their developmental ability. In vitro development to Day (D) 8 blastocyst was unaffected by PPARG ablation, as total, inner cell mass and trophectoderm cell numbers were similar between WT and KO D8 embryos. In vitro post-hatching development to D12 was also comparable between different genotypes, as embryo diameter, epiblast cell number, and embryonic disc formation and hypoblast migration rates were unaffected by the ablation. The development to tubular stages equivalent to E14 was assessed in vivo, following a heterologous embryo transfer experiment, observing that the development of extra-embryonic membranes and of the embryonic disc was not altered by PPARG ablation. In conclusion, PPARG ablation did not impaired bovine embryo development up to tubular stages.

2.
Updates Surg ; 76(3): 989-997, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38570423

RESUMEN

Ligation of the intersphincteric fistula tract has been recently employed as definitive treatment of anal fistulas. However, it carries a potential risk of continence impairment, fistula recurrence, and repeated operations. This study aimed to assess postoperative outcomes related to this procedure and evaluate the potential influence of preoperative and intraoperative features. Patients who underwent LIFT procedure between June 2012 and September 2021 were retrospectively analyzed. Patients were divided according to whether they developed fistula recurrence and on the history of a surgery prior to the LIFT. Preoperative features, postoperative outcomes, and risk factors adverse outcomes were analyzed. Forty-eight patients were included, of which 25 received primary LIFT, being the high transsphincteric fistula pattern the most frequent (62.5%). The median follow-up was 13.3 months, with a recurrence rate of 20.8%, of which the majority presented an intersphincteric fistula pattern (50%); and continence impairment rate of 16.7%. A higher prevalence of diabetes (p = 0.026) and a trend towards a higher prevalence of patients with a history of high transsphincteric fistula (0.052) were observed in the group with fistula recurrence. The history of diabetes and the operation time with a cut-off value ≥ 69 min showed a trend as a risk factors for developing fistula recurrence (0.06) and postoperative continence impairment (0.07), respectively. The LIFT procedure seems to be safe in terms of morbidity, with a reasonable incidence of recurrences, showing better results when it is primarily performed. Preoperative characteristics should be considered as they may impact outcomes.


Asunto(s)
Incontinencia Fecal , Complicaciones Posoperatorias , Fístula Rectal , Recurrencia , Humanos , Factores de Riesgo , Estudios Retrospectivos , Masculino , Femenino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Fístula Rectal/cirugía , Resultado del Tratamiento , Incontinencia Fecal/etiología , Incontinencia Fecal/epidemiología , Adulto , Ligadura/métodos , Anciano , Estudios de Seguimiento , Canal Anal/cirugía , Tempo Operativo , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos
3.
J Biomed Inform ; 145: 104475, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37595770

RESUMEN

BACKGROUND AND OBJECTIVE: Valvular heart disease (VHD) is associated with elevated mortality rates. Although transthoracic echocardiography (TTE) is the gold standard detection tool, phonocardiography (PCG) could be an alternative as it is a cost-effective and noninvasive method for cardiac auscultation. Many researchers have dedicated their efforts to improving the decision-making process and developing robust and precise approaches to assist physicians in providing reliable diagnoses of VHD. METHODS: This research proposes a novel approach for the detection of anomalous valvular heart sounds from PCG signals. The proposed approach combines orthogonal non-negative matrix factorization (ONMF) and convolutional neural network (CNN) architectures in a three-stage cascade. The aim of the proposal is to improve the learning process by identifying the optimal ONMF temporal or spectral patterns for accurate detection. In the first stage, the time-frequency representation of the input PCG signal is computed. Next, band-pass filtering is performed to locate the spectral range that is most relevant for the presence of such cardiac abnormalities. In the second stage, the temporal and spectral cardiac structures are extracted using the ONMF approach. These structures are utilized in the third stage and fed into the CNN architecture to detect abnormal heart sounds. RESULTS: Several state-of-the-art CNN architectures, such as LeNet5, AlexNet, ResNet50, VGG16 and GoogLeNet, have been evaluated to determine the effectiveness of using ONMF temporal features for VHD detection. The results reveal that the integration of ONMF temporal features with a CNN classifier significantly improve VHD detection. Specifically, the proposed approach achieves an accuracy improvement of approximately 45% when ONMF spectral features are used and 35% when time-frequency features from the short-time Fourier transform (STFT) spectrogram are used. Additionally, feeding ONMF temporal features into low-complexity CNN architectures yields competitive results comparable to those obtained with complex architectures. CONCLUSIONS: The temporal structure factorized by ONMF plays a critical role in distinguishing between normal heart sounds and abnormal heart sounds since the repeatability of normal heart cycles is disrupted by the presence of cardiac abnormalities. Consequently, the results highlight the importance of appropriate input data representation in the learning process of CNN models in the biomedical field of valvular heart sound detection.


Asunto(s)
Enfermedades de las Válvulas Cardíacas , Fonocardiografía , Humanos , Algoritmos , Enfermedades de las Válvulas Cardíacas/diagnóstico por imagen , Redes Neurales de la Computación , Fonocardiografía/métodos
4.
J Clin Virol ; 165: 105501, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37379781

RESUMEN

INTRODUCTION: Graft survival is mainly determined by rejections and infectious complications in transplant recipients. Torque Teno Virus (TTV), a nonpathogenic and ubiquitous single-stranded DNA virus, has been proposed as a biomarker of the immune status in transplant patients. This study aimed to determine the correlation between a Home-Brew TTV PCR and R-GENE®PCR; the TTV viral load kinetics in renal transplant recipients and the association with graft rejection. MATERIALS AND METHODS: Prospective cohort study on 107 adult renal transplant recipients. TTV viral load was determined in 746 plasma samples collected before and after renal transplantation by a Home-Brew PCR and a commercial PCR (R-GENE®PCR). Associations of TTV viral load with graft rejections were analyzed. RESULTS: Agreement of both PCR assays was 93.2% and Pearson correlation coefficient was r: 0.902 (95%CI: 0.8881-0.9149, p < 0.0001). TTV viral load kinetics showed an initial gradual increase reaching a peak at 3 months. This highest value was followed by a slight decrease, reaching a plateau significantly higher than the initial baseline at 6 months (p < 0.0001). Between (181-270) days post-transplantation, TTV median viral load in patients with graft rejection was significantly lower, 3.59 Log10 copies/mL (by Home-Brew PCR) and 3.10 Log10 copies/mL (by R-GENE®PCR) compared to patients without graft rejection (6.14 and 5.96 Log10 copies/mL, respectively). CONCLUSIONS: Significantly lower TTV viral load was observed in patients with renal rejection occurring at a median of 243 days post-transplantation. Given the dynamic behavior of TTV viral load post-transplantation, cut-off values for risk stratification to predict rejection might be determined in relation to the post-transplant period.


Asunto(s)
Infecciones por Virus ADN , Trasplante de Riñón , Torque teno virus , Adulto , Humanos , Trasplante de Riñón/efectos adversos , Torque teno virus/genética , Rechazo de Injerto , Cinética , Carga Viral , Estudios Prospectivos , ADN Viral/genética
5.
Comput Methods Programs Biomed ; 221: 106909, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35649297

RESUMEN

BACKGROUND AND OBJECTIVE: Auscultation is the first technique applied to the early diagnose of any cardiovascular disease (CVD) in rural areas and poor-resources countries because of its low cost and non-invasiveness. However, it highly depends on the physician's expertise to recognize specific heart sounds heard through the stethoscope. The analysis of phonocardiogram (PCG) signals attempts to segment each cardiac cycle into the four cardiac states (S1, systole, S2 and diastole) in order to develop automatic systems applied to an efficient and reliable detection and classification of heartbeats. In this work, we propose an unsupervised approach, based on time-frequency characteristics shown by cardiac sounds, to detect and classify heartbeats S1 and S2. METHODS: The proposed system consists of a two-stage cascade. The first stage performs a rough heartbeat detection while the second stage refines the previous one, improving the temporal localization and also classifying the heartbeats into types S1 and S2. The first contribution is a novel approach that combines the dissimilarity matrix with the frame-level spectral divergence to locate heartbeats using the repetitiveness shown by the heart sounds and the temporal relationships between the intervals defined by the events S1/S2 and non-S1/S2 (systole and diastole). The second contribution is a verification-correction-classification process based on a sliding window that allows the preservation of the temporal structure of the cardiac cycle in order to be applied in the heart sound classification. The proposed method has been assessed using the open access databases PASCAL, CirCor DigiScope Phonocardiogram and an additional sound mixing procedure considering both Additive White Gaussian Noise (AWGN) and different kinds of clinical ambient noises from a commercial database. RESULTS: The proposed method outperforms the detection and classification performance of other recent state-of-the-art methods. Although our proposal achieves the best average accuracy for PCG signals without cardiac abnormalities, 99.4% in heartbeat detection and 97.2% in heartbeat classification, its worst average accuracy is always above 92% for PCG signals with cardiac abnormalities, signifying an improvement in heartbeat detection/classification above 10% compared to the other state-of-the-art methods evaluated. CONCLUSIONS: The proposed method provides the best detection/classification performance in realistic scenarios where the presence of cardiac anomalies as well as different types of clinical environmental noises are active in the PCG signal. Of note, the promising modelling of the temporal structures of the heart provided by the dissimilarity matrix together with the frame-level spectral divergence, as well as the removal of a significant number of spurious heart events and recovery of missing heart events, both corrected by the proposed verification-correction-classification algorithm, suggest that our proposal is a successful tool to be applied in heart segmentation.


Asunto(s)
Ruidos Cardíacos , Procesamiento de Señales Asistido por Computador , Algoritmos , Corazón , Frecuencia Cardíaca , Fonocardiografía/métodos
6.
Semin Cell Dev Biol ; 118: 24-34, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34030948

RESUMEN

The cerebral cortex is responsible for the higher-order functions of the brain such as planning, cognition, or social behaviour. It provides us with the capacity to interact with and transform our world. The substrates of cortical functions are complex neural circuits that arise during development from the dynamic remodelling and progressive specialization of immature undefined networks. Here, we review the genetic and activity-dependent mechanisms of cortical wiring focussing on the importance of their interaction. Cortical circuits emerge from an initial set of neuronal types that engage in sequential forms of embryonic and postnatal activity. Such activities further complement the cells' genetic programs, increasing neuronal diversity and modifying the electrical properties while promoting selective connectivity. After a temporal window of enhanced plasticity, the main features of mature circuits are established. Failures in these processes can lead to neurodevelopmental disorders whose treatment remains elusive. However, a deeper dissection of cortical wiring will pave the way for innovative therapies.


Asunto(s)
Corteza Cerebral/crecimiento & desarrollo , Animales , Humanos , Ratones
7.
AIDS ; 35(7): 1091-1101, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33534201

RESUMEN

OBJECTIVE: Both HIV infection and identifying as MSM have been linked to altered rectal microbiota composition, but few studies have studied sexual behavioural associations with rectal microbiota within MSM. In addition, most rectal microbiota studies in MSM have been limited geographically to Europe and North America, and replication of findings in lower and middle-income countries is lacking. DESIGN: A cross-sectional study. METHODS: We enrolled MSM from Nairobi, Kenya, and determined their HIV/sexually transmitted infection status. Rectal specimens were obtained for 16s rRNA sequencing of the rectal microbiota, and sexual behaviour was characterized using a standardized questionnaire. Microbiome differences were modelled using nonparametric statistics, Bray-Curtis ecological distance metrics and analyses of differential taxa abundance. Multivariable linear regression was used to model HIV status and recent sexual activity as predictors of alpha diversity, controlling for a range of covariates. RESULTS: Alpha diversity was consistently lower in Kenyan HIV-infected MSM (n = 80), including those on antiretroviral therapy (ART) compared with HIV-uninfected MSM. A statistical trend was observed for clustering of HIV status by Prevotella or Bacteroides dominance (P = 0.13). Several taxa were enriched in HIV-positive men, including Roseburia, Lachnospira, Streptococcus and Granulicatella. Receptive anal sex with several types of sexual partners (paying, regular, casual) was associated with lower Chao1 and Simpson diversity, independent of HIV status, while HIV infection was associated lower Chao1 (P = 0.030) but not Simpson diversity (P = 0.49). CONCLUSION: Both HIV infection and sexual behaviour were associated with rectal microflora alpha diversity, in particular richness, but not Prevotella spp. dominance, in Kenyan MSM. Associations were more robust for sexual behaviour.


Asunto(s)
Infecciones por VIH , Microbiota , Minorías Sexuales y de Género , Estudios Transversales , Europa (Continente) , Infecciones por VIH/complicaciones , Homosexualidad Masculina , Humanos , Kenia , Masculino , América del Norte , Prevalencia , ARN Ribosómico 16S/genética , Conducta Sexual
8.
Nat Commun ; 10(1): 4549, 2019 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-31591398

RESUMEN

Interhemispheric axons of the corpus callosum (CC) facilitate the higher order functions of the cerebral cortex. According to current views, callosal and non-callosal fates are determined early after a neuron's birth, and certain populations, such as cortical layer (L) 4 excitatory neurons of the primary somatosensory (S1) barrel, project only ipsilaterally. Using a novel axonal-retrotracing strategy and GFP-targeted visualization of Rorb+ neurons, we instead demonstrate that L4 neurons develop transient interhemispheric axons. Locally restricted L4 connectivity emerges when exuberant contralateral axons are refined in an area- and layer-specific manner during postnatal development. Surgical and genetic interventions of sensory circuits demonstrate that refinement rates depend on distinct inputs from sensory-specific thalamic nuclei. Reductions in input-dependent refinement result in mature functional interhemispheric hyperconnectivity, demonstrating the plasticity and bona fide callosal potential of L4 neurons. Thus, L4 neurons discard alternative interhemispheric circuits as instructed by thalamic input. This may ensure optimal wiring.


Asunto(s)
Axones/fisiología , Cuerpo Calloso/fisiología , Vías Nerviosas/fisiología , Neuronas/fisiología , Corteza Somatosensorial/fisiología , Animales , Animales Recién Nacidos , Axones/metabolismo , Cuerpo Calloso/citología , Cuerpo Calloso/metabolismo , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Microscopía Confocal , Neuronas/metabolismo , Células Receptoras Sensoriales/metabolismo , Células Receptoras Sensoriales/fisiología , Corteza Somatosensorial/citología , Corteza Somatosensorial/metabolismo , Tálamo/citología , Tálamo/metabolismo , Tálamo/fisiología
9.
J Intellect Disabil Res ; 63(10): 1248-1261, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31169961

RESUMEN

BACKGROUND: Although in the last decade some research has emerged on temperament in autism spectrum disorder (ASD), this research has primarily focused on the differences between children with ASD and their typically developing peers rather than the stability or change in temperament in this population. Thus, the goal of this study was to examine temperament over time in children with ASD, developmental delays (DD) and typical development (TD). Temperament differences were also compared among the three groups. METHODS: To accomplish this, parents rated children's temperament at Time 1 (T1) and Time 2 (T2) using the Carey Temperament Scales (CTS). RESULTS: Results from the study showed that at T1, parents of children with ASD rated their children as more withdrawn (i.e. approach), and emotionally negative (i.e. mood), and less distractible and adaptable than parents of children with TD and DD. Also, children with ASD were rated as more intense and children with DD as less distractible than their TD peers. Similarly, at T2, children with ASD were rated more withdrawn, and emotionally negative, and less persistent, rhythmic, adaptable and distractible than children with TD and DD. Also, children with ASD were rated as more active than their DD peers. Regarding stability, parent ratings of temperament appeared stable over time in the TD group, but ratings varied substantially in the ASD or DD groups. That is, for the ASD group, activity and approach at T1 were significantly associated with their corresponding dimensions at T2. However, for the TD group, rhythmicity, approach, intensity and mood at T1 were significantly associated with those dimensions at T2. No associations were found in the DD group. Regarding change, parents reported change in rhythmicity, persistence and threshold between T1 and T2 in the ASD group. Similarly, parents reported change in rhythmicity, approach and threshold between T1 and T2 in the DD group. Lastly, parents of TD children reported change in adaptability, persistence and distractibility between T1 and T2. CONCLUSIONS: These findings are novel in that children with ASD appear to have less stable temperament profile and different change patterns than children with TD or DD. Similar to previous research, children with ASD were described by their parents as experiencing more temperamental difficulties.


Asunto(s)
Trastorno del Espectro Autista/fisiopatología , Desarrollo Infantil/fisiología , Discapacidades del Desarrollo/fisiopatología , Temperamento/fisiología , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino
10.
Int J Food Microbiol ; 292: 8-12, 2019 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-30553180

RESUMEN

The aim of this study was to detect, to quantify and to characterize MRSA in broiler meat samples with skin. Furthermore, we compared an isolation method using a second selective enrichment step (method A) with a simpler method omitting this step (method B). For quantification we used a direct plating method on selective agar plates and a "Most probable number" (MPN) technique for estimation of low numbers of MRSA. Presumptive MRSA colonies were confirmed by MALDI-TOF and by PCR. After confirmation the isolated MRSA were characterized by spa-typing and, if necessary, by multi-locus sequence typing. Method B detected more MRSA-positive samples (16.7%, n = 215) than method A (12.1%). However, method B also produced more false positive results (28.4%).The highest estimated number of MRSA in fresh broiler meat with skin was 1100 MPN/g, but in most positive samples (80.1%) the estimated numbers of MRSA were lower than 10 MPN/g. Thus, the numbers of MRSA in the samples were too low to detect using the spread plate technique. Ten different spa-types were identified. Six of these with 69% of the isolates were assigned to the clonal complex CC398 (t034; t011; t2576; t571; t5452; t1457). Spa-types t1430, t13177 and t899 can be assigned to CC9. Spa-type t304 was identified as MLST-type ST6. In conclusion, we provide quantitative data on low level contamination of fresh broiler meat with MRSA. Most isolated MRSA were from livestock associated spa-types. Omitting the second enrichment step was associated with an increase in sensitivity but lower specificity of the cultural method.


Asunto(s)
Carne/microbiología , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Piel/microbiología , Animales , Pollos , Alemania , Humanos , Ganado/microbiología , Staphylococcus aureus Resistente a Meticilina/genética , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Infecciones Estafilocócicas/microbiología
11.
Med. interna Méx ; 33(5): 690-695, sep.-oct. 2017. tab, graf
Artículo en Español | LILACS | ID: biblio-894311

RESUMEN

Resumen La miocarditis es una enfermedad inflamatoria del tejido miocárdico, la poca incidencia y la variabilidad del cuadro clínico hacen que el diagnóstico sea de exclusión. La causa es principalmente viral, aunque en los últimos años ha habido una transición en el virus causante. El tratamiento es controvertido y el pronóstico en los pacientes con miocardiopatía dilatada es ominoso. Comunicamos el caso clínico de una paciente que cursó con miocarditis secundaria a citomegalovirus en el servicio de Cardiología del Hospital Regional Puebla. Se realiza una revisión bibliográfica del tema para ayudar a establecer la causa, el tratamiento y posteriormente el pronóstico al alta hospitalaria.


Abstract Myocarditis is an inflammatory disease of the myocardium, due to the low incidence and the variability of the clinical course, the diagnosis is an exclusion one. The etiology is mainly viral, although a shift of the specific agent in recent years has taken place. Treatment is controversial and the prognosis related to dilated myocardiopathy is generally bad. We present the clinical case of a patient with myocarditis due to cytomegalovirus in the cardiology department of our Hospital. We conducted a bibliographic review of the topic to help to determine the etiology, the treatment and to be able to establish a prognosis at the discharge.

12.
Rev. pediatr. electrón ; 14(1): 13-25, 2017. img.
Artículo en Español | LILACS | ID: biblio-968887

RESUMEN

Cada año, cerca de 6 millones de niños mueren por enfermedades prevenibles o fácilmente tratadas. El 95% se produce en países subdesarrollados, siendo la neumonía la causa más prevalente muertes en menores de 5 años (18%). La hipoxemia es la causa de los decesos en estos individuos. La aplicación de O2 como medida terapéutica para tratar o prevenirla es una de las indicaciones más frecuente que debe realizar un clínico. Este escrito trata de integrar en forma muy resumida los conceptos básicos que involucran a la oxigeno terapia, cuándo aplicar O2, con que equipos y aditamentos más apropiados.


Around 6 million children died of preventable or easily treatable diseases each year. Ninety five per cent are produced in undeveloped countries, being pneumonia the leading cause of death of children of 5 years or less (18%) and hypoxemia is the cause of dead. Oxygen therapy to treat or prevent this, as a therapeutic measure, is one of the most commons indicationsthat must be performed by aclinician. The review summarized the basic concepts of oxygen administration, when and how, with which equipment, oxygen delivery devices, dangers and its precautions.


Asunto(s)
Humanos , Niño , Terapia por Inhalación de Oxígeno/instrumentación , Terapia por Inhalación de Oxígeno/métodos , Hipoxia/prevención & control , Oxígeno/administración & dosificación
13.
Sci Rep ; 6: 35370, 2016 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-27734943

RESUMEN

Retinitis pigmentosa (RP), the most frequent form of inherited retinal dystrophy is characterized by progressive photoreceptor degeneration. Many genes have been implicated in RP development, but several others remain to be identified. Using a combination of homozygosity mapping, whole-exome and targeted next-generation sequencing, we found a novel homozygous nonsense mutation in SAMD11 in five individuals diagnosed with adult-onset RP from two unrelated consanguineous Spanish families. SAMD11 is ortholog to the mouse major retinal SAM domain (mr-s) protein that is implicated in CRX-mediated transcriptional regulation in the retina. Accordingly, protein-protein network analysis revealed a significant interaction of SAMD11 with CRX. Immunoblotting analysis confirmed strong expression of SAMD11 in human retina. Immunolocalization studies revealed SAMD11 was detected in the three nuclear layers of the human retina and interestingly differential expression between cone and rod photoreceptors was observed. Our study strongly implicates SAMD11 as novel cause of RP playing an important role in the pathogenesis of human degeneration of photoreceptors.


Asunto(s)
Proteínas del Ojo/metabolismo , Proteínas de Homeodominio/metabolismo , Distrofias Retinianas/genética , Retinitis Pigmentosa/genética , Transactivadores/metabolismo , Anciano , Animales , Proteínas Co-Represoras/metabolismo , Codón sin Sentido , Estudios de Cohortes , Hibridación Genómica Comparativa , Consanguinidad , Análisis Mutacional de ADN , Exoma , Femenino , Regulación de la Expresión Génica , Genes Recesivos , Homocigoto , Humanos , Masculino , Ratones , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Mapeo de Interacción de Proteínas , Retina/metabolismo , Retina/fisiopatología , Distrofias Retinianas/etiología , Distrofias Retinianas/metabolismo , Células Fotorreceptoras Retinianas Bastones/metabolismo , Retinitis Pigmentosa/etiología , Retinitis Pigmentosa/metabolismo , España , Factores de Transcripción/metabolismo
14.
J Leukoc Biol ; 100(2): 371-80, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-26856994

RESUMEN

Allergic eye disease, as in most forms of atopy, ranges in severity among individuals from immediate hypersensitivity to a severe and debilitating chronic disease. Dendritic cells play a key role in stimulating pathogenic T cells in allergen re-exposure, or secondary responses. However, molecular cues by dendritic cells underpinning allergic T cell response levels and the impact that this control has on consequent severity of allergic disease are poorly understood. Here, we show that a deficiency in thrombospondin-1, a matricellular protein known to affect immune function, has subsequent effects on downstream T cell responses during allergy, as revealed in an established mouse model of allergic eye disease. More specifically, we demonstrate that a thrombospondin-1 deficiency specific to dendritic cells leads to heightened secondary T cell responses and consequent clinical disease. Interestingly, whereas thrombospondin-1-deficient dendritic cells augmented activity of allergen-primed T cells, this increase was not recapitulated with naïve T cells in vitro. The role of dendritic cell-derived thrombospondin-1 in regulating secondary allergic T cell responses was confirmed in vivo, as local transfer of thrombospondin-1-sufficient dendritic cells to the ocular mucosa of thrombospondin-1 null hosts prevented the development of augmented secondary T cell responses and heightened allergic eye disease clinical responses. Finally, we demonstrate that topical instillation of thrombospondin-1-derived peptide reduces T cell activity and clinical progression of allergic eye disease. Taken together, this study reveals an important modulatory role of dendritic cell-derived thrombospondin-1 on secondary allergic T cell responses and suggests the possible dysregulation of dendritic cell-derived thrombospondin-1 expression as a factor in allergic eye disease severity.


Asunto(s)
Alérgenos/inmunología , Células Dendríticas/inmunología , Oftalmopatías/inmunología , Hipersensibilidad/inmunología , Linfocitos T/inmunología , Trombospondina 1/fisiología , Animales , Oftalmopatías/inducido químicamente , Oftalmopatías/metabolismo , Hipersensibilidad/metabolismo , Activación de Linfocitos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ovalbúmina/toxicidad
15.
J Gen Virol ; 96(8): 2074-2078, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25918237

RESUMEN

Influenza epidemics affect all age groups, although children, the elderly and those with underlying medical conditions are the most severely affected. Whereas co-morbidities are present in 50% of fatal cases, 25-50% of deaths are in apparently healthy individuals. This suggests underlying genetic determinants that govern infection severity. Although some viral factors that contribute to influenza disease are known, the role of host genetic factors remains undetermined. Data for small cohorts of influenza-infected patients are contradictory regarding the potential role of chemokine receptor 5 deficiency (CCR5-Δ32 mutation, a 32 bp deletion in the CCR5 gene) in the outcome of influenza virus infection. We tested 171 respiratory samples from influenza patients (2009 pandemic) for CCR5-Δ32 and evaluated its correlation with patient mortality. CCR5-Δ32 patients (17.4%) showed a higher mortality rate than WT individuals (4.7%; P = 0.021), which indicates that CCR5-Δ32 patients are at higher risk than the normal population of a fatal outcome in influenza infection.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A/fisiología , Gripe Humana/genética , Gripe Humana/mortalidad , Receptores CCR5/deficiencia , Adolescente , Adulto , Anciano , Niño , Femenino , Eliminación de Gen , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Subtipo H1N1 del Virus de la Influenza A/genética , Gripe Humana/metabolismo , Gripe Humana/virología , Masculino , Persona de Mediana Edad , Receptores CCR5/genética , Adulto Joven
16.
Cell Death Differ ; 22(7): 1158-69, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25501598

RESUMEN

The embryonic stem cell (ESC)-enriched miR-294/302 family and the somatic cell-enriched let-7 family stabilizes the self-renewing and differentiated cell fates, respectively. The mechanisms underlying these processes remain unknown. Here we show that among many pathways regulated by miR-294/302, the combinatorial suppression of epithelial-mesenchymal transition (EMT) and apoptotic pathways is sufficient in maintaining the self-renewal of ESCs. The silencing of ESC self-renewal by let-7 was accompanied by the upregulation of several EMT regulators and the induction of apoptosis. The ectopic activation of either EMT or apoptotic program is sufficient in silencing ESC self-renewal. However, only combined but not separate suppression of the two programs inhibited the silencing of ESC self-renewal by let-7 and several other differentiation-inducing miRNAs. These findings demonstrate that combined repression of the EMT and apoptotic pathways by miR-294/302 imposes a synergistic barrier to the silencing of ESC self-renewal, supporting a model whereby miRNAs regulate complicated cellular processes through synergistic repression of multiple targets or pathways.


Asunto(s)
Autorrenovación de las Células/fisiología , Células Madre Embrionarias/fisiología , Transición Epitelial-Mesenquimal/fisiología , MicroARNs/fisiología , Animales , Apoptosis , Células Madre Embrionarias/metabolismo , Ratones , Transducción de Señal
17.
J Dairy Sci ; 97(2): 598-608, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24290815

RESUMEN

Chihuahua cheese or Mennonite cheese is one of the most popular and consumed cheeses in Mexico and by the Hispanic community in the United States. According to local producers the yield of Chihuahua cheese ranges from 9 to 9.5 kg of cheese from 100 kg of milk. Cheese yield is a crucial determinant of profitability in cheese-manufacturing plants; therefore, different methods have been developed to increase it. In this work, a miniature Chihuahua-type cheese model was used to assess the effect of a phospholipase A1 (PL-A1) and exopolysaccharide (EPS)-producing bacteria (separately and in combination) on the yield, microstructure, and texture of cheese. Four different cheeses were manufactured: cheese made with PL-A1, cheese made with EPS-producing bacteria, cheese with both PL-A1 and EPS-producing bacteria, and a cheese control without PL-A1 or EPS-producing bacteria. The compositional analysis of cheese was carried out using methods of AOAC International (Washington, DC). The actual yield and moisture-adjusted yield were calculated for all cheese treatments. Texture profile analyses of cheeses were performed using a texture analyzer. Micrographs were obtained by electron scanning microscopy. Fifty panelists carried out sensorial analysis using ranking tests. Incorporation of EPS-producing bacteria in the manufacture of cheese increased the moisture content and water activity. In contrast, the addition of PL-A1 did not increase fat retention or cheese yield. The use of EPS alone improved the cheese yield by increasing water and fat retention, but also caused a negative effect on the texture and flavor of Chihuahua cheese. The use of EPS-producing bacteria in combination with PL-A1 improved the cheese yield and increased the moisture and fat content. The cheeses with the best flavor and texture were those manufactured with PL-A1 and the cheeses manufactured with the combination of PL-A1 and EPS-producing culture.


Asunto(s)
Queso/análisis , Microbiología de Alimentos , Fosfolipasas A1/análisis , Polisacáridos Bacterianos/metabolismo , Animales , Bacterias/metabolismo , Queso/microbiología , México , Leche/química , Gusto
18.
Am J Transplant ; 13(5): 1181-92, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23489547

RESUMEN

Allergic diseases rob corneal allografts of immune privilege and increase immune rejection. Corneal allograft rejection in BALB/c allergic hosts was analyzed using a short ragweed (SWR) pollen model of allergic conjunctivitis. Allergic conjunctivitis did not induce exaggerated T-cell responses to donor C57BL/6 (B6) alloantigens or stimulate cytotoxic T lymphocyte (CTL) responses. Allergic conjunctivitis did affect T regulatory cells (Tregs) that support graft survival. Exogenous IL-4, but not IL-5 or IL-13, prevented Treg suppression of CD4(+) effector T cells isolated from naïve mice. However, mice with allergic conjunctivitis developed Tregs that suppressed CD4(+) effector T-cell proliferation. In addition, IL-4 did not inhibit Treg suppression of IL-4Rα(-/-) CD4(+) T-cell responses, suggesting that IL-4 rendered effector T cells resistant to Tregs. SRW-sensitized IL-4Rα(-/-) mice displayed the same 50% graft survival as nonallergic WT mice, that was significantly less than the 100% rejection that occurred in allergic WT hosts, supporting the role of IL-4 in the abrogation of immune privilege. Moreover, exacerbation of corneal allograft rejection in allergic mice was reversed by administering anti-IL-4 antibody. Thus, allergy-induced exacerbation of corneal graft rejection is due to the production of IL-4, which renders effector T cells resistant to Treg suppression of alloimmune responses.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Conjuntivitis Alérgica/complicaciones , Trasplante de Córnea , Rechazo de Injerto/etiología , Activación de Linfocitos/inmunología , Linfocitos T Reguladores/inmunología , Animales , Conjuntivitis Alérgica/inmunología , Conjuntivitis Alérgica/metabolismo , Córnea/inmunología , Citocinas/inmunología , Citocinas/metabolismo , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Femenino , Rechazo de Injerto/inmunología , Rechazo de Injerto/patología , Ratones , Ratones Endogámicos BALB C
19.
Tetrahedron Lett ; 50(49): 6803-6806, 2009 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-26989268

RESUMEN

Extraordinary stereoselectivity, approaching 100%, has been reported in the reductions of d-benzaldehydes by B-isopinocampheyl-9-borabicyclo[3.3.1]nonane (Alpine-Borane). This is likely because of the extreme size disparity of groups on either side of the carbonyl. Here, we present a structure-reactivity study whereby the reductions of variably substituted d-benzaldehydes are explored using highly sensitive measures for enantiomeric excess and relative reactivity. These results are compared to the relative rates predicted from density functional calculations. The results indicate that 2,6-disubstitution adversely affects the stereoselectivity by means of a non-selective reduction via the dehydroboration product of Alpine-Borane, 9-borabicyclo[3.3.1]nonane.

20.
J Clin Microbiol ; 44(4): 1519-29, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16597885

RESUMEN

Here we propose the use of a 216-nucleotide fragment located in the carboxyl terminus of the E gene (E-COOH) and a pairwise-based comparison method for genotyping of dengue virus 1 (DENV-1) strains. We have applied this method to the detection and characterization of DENV-1 in serum samples from travelers returning from the tropics. The results obtained with the typing system correlate with the results obtained by comparison of the sequences of the entire E gene of the strains. The approach demonstrates utility in plotting the distribution and circulation of different genotypes of DENV-1 and also suggests the presence of two new clades of Indian strains. The integration of the method with an online database and a typing characterization tool enhances its strength. Additionally, the analysis of the complete E gene of DENV-1 strains suggested the occurrence of a nondescribed recombination event in the China GD23-95 strain. We propose the use of this methodology as a tool for real-time epidemiological surveillance of dengue virus infections and their pathogenesis.


Asunto(s)
ADN Viral/análisis , Virus del Dengue/clasificación , Dengue/virología , Genoma Viral , Epidemiología Molecular/métodos , Dengue/epidemiología , Virus del Dengue/genética , Virus del Dengue/patogenicidad , Humanos , India/epidemiología , Filogenia
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