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Dynamic changes in the expression of transcription factors (TFs) can influence the specification of distinct CD8+ T cell fates, but the observation of equivalent expression of TFs among differentially fated precursor cells suggests additional underlying mechanisms. Here we profiled the genome-wide histone modifications, open chromatin and gene expression of naive, terminal-effector, memory-precursor and memory CD8+ T cell populations induced during the in vivo response to bacterial infection. Integration of these data suggested that the expression and binding of TFs contributed to the establishment of subset-specific enhancers during differentiation. We developed a new bioinformatics method using the PageRank algorithm to reveal key TFs that influence the generation of effector and memory populations. The TFs YY1 and Nr3c1, both constitutively expressed during CD8+ T cell differentiation, regulated the formation of terminal-effector cell fates and memory-precursor cell fates, respectively. Our data define the epigenetic landscape of differentiation intermediates and facilitate the identification of TFs with previously unappreciated roles in CD8+ T cell differentiation.
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Linfocitos T CD8-positivos/fisiología , Epigénesis Genética , Listeriosis/inmunología , Receptores de Glucocorticoides/metabolismo , Subgrupos de Linfocitos T/fisiología , Factor de Transcripción YY1/metabolismo , Animales , Linfocitos T CD8-positivos/microbiología , Diferenciación Celular/genética , Biología Computacional , Elementos de Facilitación Genéticos/genética , Perfilación de la Expresión Génica , Histonas/metabolismo , Memoria Inmunológica/genética , Ratones , Ratones Endogámicos C57BL , Receptores de Glucocorticoides/genética , Subgrupos de Linfocitos T/microbiología , Factor de Transcripción YY1/genéticaRESUMEN
In response to acute infection, naive CD8+ T cells expand, differentiate into effector cells, and then contract to a long-lived pool of memory cells after pathogen clearance. During chronic infections or in tumors, CD8+ T cells acquire an "exhausted" phenotype. Here we present genome-wide comparisons of chromatin accessibility and gene expression from endogenous CD8+ T cells responding to acute and chronic viral infection using ATAC-seq and RNA-seq techniques. Acquisition of effector, memory, or exhausted phenotypes was associated with stable changes in chromatin accessibility away from the naive T cell state. Regions differentially accessible between functional subsets in vivo were enriched for binding sites of transcription factors known to regulate these subsets, including E2A, BATF, IRF4, T-bet, and TCF1. Exhaustion-specific accessible regions were enriched for consensus binding sites for NFAT and Nr4a family members, indicating that chronic stimulation confers a unique accessibility profile on exhausted cells.
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Linfocitos T CD8-positivos/inmunología , Ensamble y Desensamble de Cromatina/inmunología , Expresión Génica/inmunología , Memoria Inmunológica/inmunología , Activación de Linfocitos/inmunología , Animales , Infecciones por Arenaviridae/inmunología , Cromatina , Modelos Animales de Enfermedad , Perfilación de la Expresión Génica , Virus de la Coriomeningitis Linfocítica , Ratones , Ratones Endogámicos C57BL , Ratones TransgénicosRESUMEN
CTL differentiation is controlled by the crosstalk of various transcription factors and epigenetic modulators. Uncovering this process is fundamental to improving immunotherapy and designing novel therapeutic approaches. In this study, we show that polycomb repressive complex 1 subunit chromobox (Cbx)4 favors effector CTL differentiation in a murine model. Cbx4 deficiency in CTLs induced a transcriptional signature of memory cells and increased the memory CTL population during acute viral infection. It has previously been shown that besides binding to H3K27me3 through its chromodomain, Cbx4 functions as a small ubiquitin-like modifier (SUMO) E3 ligase in a SUMO-interacting motifs (SIM)-dependent way. Overexpression of Cbx4 mutants in distinct domains showed that this protein regulates CTL differentiation primarily in an SIM-dependent way and partially through its chromodomain. Our data suggest a novel role of a polycomb group protein Cbx4 controlling CTL differentiation and indicated SUMOylation as a key molecular mechanism connected to chromatin modification in this process.
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Complejo Represivo Polycomb 1 , Ubiquitina-Proteína Ligasas , Animales , Ratones , Linfocitos T CD8-positivos/metabolismo , Diferenciación Celular , Complejo Represivo Polycomb 1/genética , Complejo Represivo Polycomb 1/metabolismo , Proteínas del Grupo Polycomb/genética , Proteínas del Grupo Polycomb/metabolismo , Ubiquitina-Proteína Ligasas/metabolismoRESUMEN
Mitochondria and endoplasmic reticulum (ER) contact sites (MERCs) are protein- and lipid-enriched hubs that mediate interorganellar communication by contributing to the dynamic transfer of Ca2+, lipid, and other metabolites between these organelles. Defective MERCs are associated with cellular oxidative stress, neurodegenerative disease, and cardiac and skeletal muscle pathology via mechanisms that are poorly understood. We previously demonstrated that skeletal muscle-specific knockdown (KD) of the mitochondrial fusion mediator optic atrophy 1 (OPA1) induced ER stress and correlated with an induction of Mitofusin-2, a known MERC protein. In the present study, we tested the hypothesis that Opa1 downregulation in skeletal muscle cells alters MERC formation by evaluating multiple myocyte systems, including from mice and Drosophila, and in primary myotubes. Our results revealed that OPA1 deficiency induced tighter and more frequent MERCs in concert with a greater abundance of MERC proteins involved in calcium exchange. Additionally, loss of OPA1 increased the expression of activating transcription factor 4 (ATF4), an integrated stress response (ISR) pathway effector. Reducing Atf4 expression prevented the OPA1-loss-induced tightening of MERC structures. OPA1 reduction was associated with decreased mitochondrial and sarcoplasmic reticulum, a specialized form of ER, calcium, which was reversed following ATF4 repression. These data suggest that mitochondrial stress, induced by OPA1 deficiency, regulates skeletal muscle MERC formation in an ATF4-dependent manner.
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Factor de Transcripción Activador 4 , Enfermedades Neurodegenerativas , Animales , Ratones , Factor de Transcripción Activador 4/genética , Factor de Transcripción Activador 4/metabolismo , Calcio/metabolismo , Retículo Endoplásmico/metabolismo , Estrés del Retículo Endoplásmico/genética , Lípidos , Mitocondrias/metabolismo , Músculo Esquelético/metabolismo , Enfermedades Neurodegenerativas/patología , Masculino , Ratones Endogámicos C57BL , Células Cultivadas , GTP Fosfohidrolasas/metabolismoRESUMEN
The hormone erythroferrone (ERFE) is produced by erythroid cells in response to hemorrhage, hypoxia, or other erythropoietic stimuli, and it suppresses the hepatic production of the iron-regulatory hormone hepcidin, thereby mobilizing iron for erythropoiesis. Suppression of hepcidin by ERFE is believed to be mediated by interference with paracrine bone morphogenetic protein (BMP) signaling that regulates hepcidin transcription in hepatocytes. In anemias with ineffective erythropoiesis, ERFE is pathologically overproduced, but its contribution to the clinical manifestations of these anemias is not well understood. We generated 3 lines of transgenic mice with graded erythroid overexpression of ERFE and found that they developed dose-dependent iron overload, impaired hepatic BMP signaling, and relative hepcidin deficiency. These findings add to the evidence that ERFE is a mediator of iron overload in conditions in which ERFE is overproduced, including anemias with ineffective erythropoiesis. At the highest levels of ERFE overexpression, the mice manifested decreased perinatal survival, impaired growth, small hypofunctional kidneys, decreased gonadal fat depots, and neurobehavioral abnormalities, all consistent with impaired organ-specific BMP signaling during development. Neutralizing excessive ERFE in congenital anemias with ineffective erythropoiesis may not only prevent iron overload but may have additional benefits for growth and development.
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Citocinas/metabolismo , Discapacidades del Desarrollo/metabolismo , Células Eritroides/metabolismo , Sobrecarga de Hierro/metabolismo , Proteínas Musculares/metabolismo , Animales , Proteínas Morfogenéticas Óseas/metabolismo , Citocinas/genética , Discapacidades del Desarrollo/etiología , Discapacidades del Desarrollo/genética , Células Eritroides/citología , Femenino , Hepcidinas/metabolismo , Sobrecarga de Hierro/etiología , Sobrecarga de Hierro/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Proteínas Musculares/genética , Transducción de Señal , Regulación hacia ArribaRESUMEN
During persistent antigen stimulation, CD8(+) T cells show a gradual decrease in effector function, referred to as exhaustion, which impairs responses in the setting of tumors and infections. Here we demonstrate that the transcription factor NFAT controls the program of T cell exhaustion. When expressed in cells, an engineered form of NFAT1 unable to interact with AP-1 transcription factors diminished T cell receptor (TCR) signaling, increased the expression of inhibitory cell surface receptors, and interfered with the ability of CD8(+) T cells to protect against Listeria infection and attenuate tumor growth in vivo. We defined the genomic regions occupied by endogenous and engineered NFAT1 in primary CD8(+) T cells and showed that genes directly induced by the engineered NFAT1 overlapped with genes expressed in exhausted CD8(+) T cells in vivo. Our data show that NFAT promotes T cell anergy and exhaustion by binding at sites that do not require cooperation with AP-1.
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Linfocitos T CD8-positivos/inmunología , Anergia Clonal/genética , Factores de Transcripción NFATC/fisiología , Proteínas Recombinantes/farmacología , Factor de Transcripción AP-1/metabolismo , Animales , Células Cultivadas , Anergia Clonal/efectos de los fármacos , Regulación de la Expresión Génica/genética , Listeria monocytogenes/inmunología , Listeriosis/inmunología , Listeriosis/microbiología , Activación de Linfocitos/inmunología , Ratones , Ratones Transgénicos , Factores de Transcripción NFATC/genética , Neoplasias/inmunología , Regiones Promotoras Genéticas/genética , Receptores de Antígenos de Linfocitos T/inmunología , Proteínas Recombinantes/genéticaRESUMEN
AIMS: We developed three new analogs of the antimicrobial peptide (AMP) Citropin 1.1: DAN-1-13, AJP-1-1, and HHX-2-28, and tested their potential antimicrobial and antibiofilm activities against Staphylococcus aureus and S. pseudintermedius. Potential cytotoxic or hemolytic effects were determined using cultured human keratinocytes and erythrocytes to determine their safety. METHODS AND RESULTS: To assess the antimicrobial activity of each compound, minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) were determined against methicillin-resistant and methicillin-susceptible strains of S. aureus and S. pseudintermedius. Activity against newly formed and mature biofilms was determined in two clinical isolates using spectrophotometry and scanning electron microscopy (SEM). All three compounds exhibited antimicrobial and bactericidal activity against all studied S. aureus and S. pseudintermedius strains, with MICs ranging from 4-32 µg ml-1 and MBCs ranging from 8-128 µg ml-1. Subinhibitory concentrations of all compounds also showed ant-biofilm activity in the two tested isolates. All compounds exhibited limited cytotoxic and hemolytic activity. CONCLUSIONS: Novel analogs of Citropin 1.1 exhibit antimicrobial and bactericidal activities against S. aureus and S. pseudintermedius isolates and inhibit the biofilm formation of these bacteria.
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Antibacterianos , Biopelículas , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus , Staphylococcus , Biopelículas/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Humanos , Antibacterianos/farmacología , Staphylococcus/efectos de los fármacos , Péptidos Antimicrobianos/farmacología , Péptidos Antimicrobianos/química , Eritrocitos/efectos de los fármacos , Queratinocitos/efectos de los fármacosRESUMEN
The hip capsule and capsular ligaments play crucial roles in providing hip stability and mobility. Their role in hip pathologies is being increasingly recognized, underscoring the need for thorough imaging evaluation, which is better performed through MRI-arthrography. Various diseases affect the hip capsule directly or indirectly. Improper mechanical loading, as seen in conditions such as femoroacetabular impingement or chondrolabral pathology, can induce capsule thickening, whereas thinning and laxity of the capsule are characteristics of microinstability. Inflammatory conditions, including adhesive capsulitis of the hip, crystal deposition disease, polymyalgia rheumatica, and infections, also lead to capsular changes. Traumatic events, particularly posterior hip dislocations, cause capsule ligament disruption and may lead to hip macroinstability. Friction syndromes can lead to capsular edema due to impingement of the adjacent capsule. Hip arthroscopy can result in various postoperative findings ranging from fibrotic adhesions to focal or extensive capsule discontinuation. Although the significance of hip capsule thickness and morphology in the pathogenesis of hip diseases remains unclear, radiologists must recognize capsule alterations on imaging evaluation. These insights can aid clinicians in accurately diagnosing and effectively managing patients with hip conditions.
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BACKGROUND: Important evidence has been constantly produced and needs to be converted into practice. Professional consumption of such evidence may be a barrier to its implementation. Then, effective implementation of evidence-based interventions in clinical practice leans on the understanding of how professionals value attributes when choosing between options for dental care, permitting to guide this implementation process by maximizing strengthens and minimizing barriers related to that. METHODS: This is part of a broader project investigating the potential of incorporating scientific evidence into clinical practice and public policy recommendations and guidelines, identifying strengths and barriers in such an implementation process. The present research protocol comprises a Discrete Choice Experiment (DCE) from the Brazilian oral health professionals' perspective, aiming to assess how different factors are associated with professional decision-making in dental care, including the role of scientific evidence. Different choice sets will be developed, either focusing on understanding the role of scientific evidence in the professional decision-making process or on understanding specific attributes associated with different interventions recently tested in randomized clinical trials and available as newly produced scientific evidence to be used in clinical practice. DISCUSSION: Translating research into practice usually requires time and effort. Shortening this process may be useful for faster incorporation into clinical practice and beneficial to the population. Understanding the context and professionals' decision-making preferences is crucial to designing more effective implementation and/or educational initiatives. Ultimately, we expect to design an efficient implementation strategy that overcomes threats and potential opportunities identified during the DCEs, creating a customized structure for dental professionals. TRIAL REGISTRATION: https://osf.io/bhncv .
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Práctica Clínica Basada en la Evidencia , Odontología Pediátrica , Niño , Humanos , Proyectos de Investigación , Atención Odontológica , BrasilRESUMEN
Osteocytes are the most abundant type of bone cell and play crucial roles in bone health. Osteocytes sense mechanical stress and orchestrate osteoblasts and osteoclasts to maintain bone density and strength. Beyond this, osteocytes have also emerged as key regulators of organ crosstalk, and they function as endocrine organs via their roles in secreting factors that mediate signaling within their neighboring bone cells and in distant tissues. As such, osteocyte dysfunction has been associated with the bone abnormalities seen across a spectrum of chronic kidney disease. Specifically, dysregulated osteocyte morphology and signaling have been observed in the earliest stages of chronic kidney disease and have been suggested to contribute to kidney disease progression. More important, US Food and Drug Administration-approved inhibitors of osteocytic secreted proteins, such as fibroblast growth factor 23 and sclerostin, have been used to treat bone diseases. The present mini review highlights new research that links dysfunctional osteocytes to the pathogenesis of chronic kidney disease mineral and bone disorder.
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Thrombopoietin receptor agonists (TPO-RAs) stimulate platelet production, which might restore immunological tolerance in primary immune thrombocytopenia (ITP). The iROM study investigated romiplostim's immunomodulatory effects. Thirteen patients (median age, 31 years) who previously received first-line treatment received romiplostim for 22 weeks, followed by monitoring until week 52. In addition to immunological data, secondary end-points included the sustained remission off-treatment (SROT) rate at 1 year, romiplostim dose, platelet count and bleedings. Scheduled discontinuation of romiplostim and SROT were achieved in six patients with newly diagnosed ITP, whereas the remaining seven patients relapsed. Romiplostim dose titration was lower and platelet count response was stronger in patients with SROT than in relapsed patients. In all patients, regulatory T lymphocyte (Treg) counts increased until study completion and the counts were higher in patients with SROT. Interleukin (IL)-4, IL-9 and IL-17F levels decreased significantly in all patients. FOXP3 (Treg), GATA3 (Th2) mRNA expression and transforming growth factor-ß levels increased in patients with SROT. Treatment with romiplostim modulates the immune system and possibly influences ITP prognosis. A rapid increase in platelet counts is likely important for inducing immune tolerance. Better outcomes might be achieved at an early stage of autoimmunity, but clinical studies are needed for confirmation.
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Púrpura Trombocitopénica Idiopática , Humanos , Adulto , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Inmunomodulación , Tolerancia Inmunológica , Proteínas Recombinantes de Fusión/farmacología , Proteínas Recombinantes de Fusión/uso terapéuticoRESUMEN
Neuropathic pain (NP) represents a complex disorder with sensory, cognitive, and emotional symptoms. The medial prefrontal cortex (mPFC) takes critical regulatory roles and may change functionally and morphologically during chronic NP. There needs to be a complete understanding of the neurophysiological and psychopharmacological bases of the NP phenomenon. This study aimed to investigate the participation of the infralimbic division (IFL) of the mPFC in chronic NP, as well as the role of the N-methyl-D-aspartic acid receptor (NMDAr) in the elaboration of chronic NP. Male Wistar rats were submitted to the von Frey and acetone tests to assess mechanical and cold allodynia after 21 days of chronic constriction injury (CCI) of the sciatic nerve or Sham-procedure ("false operated"). Electrical neurostimulation of the IFL/mPFC was performed by low-frequency stimuli (20 µA, 100 Hz) applied for 15 s by deep brain stimulation (DBS) device 21 days after CCI. Either cobalt chloride (CoCl2 at 1.0 mM/200 nL), NMDAr agonist (at 0.25, 1.0, and 2.0 nmol/200 nL) or physiological saline (200 nL) was administered into the IFL/mPFC. CoCl2 administration in the IFL cortex did not alter either mechanical or cold allodynia. DBS stimulation of the IFL cortex decreased mechanical allodynia in CCI rats. Chemical stimulation of the IFL cortex by an NMDA agonist (at 2.0 nmol) decreased mechanical allodynia. NMDA at any dose (0.25, 1.0, and 2.0 nmol) reduced the flicking/licking duration in the cold test. These findings suggest that the IFL/mPFC and the NMDAr of the neocortex are involved in attenuating chronic NP in rats.
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Hiperalgesia , Neuralgia , Ratas , Masculino , Animales , N-Metilaspartato/farmacología , Dimensión del Dolor , Ratas Wistar , Neuralgia/terapia , Receptores de N-Metil-D-Aspartato/metabolismo , Corteza Prefrontal/metabolismoRESUMEN
Naive CD8+ T cells, upon encountering their cognate Ag in vivo, clonally expand and differentiate into distinct cell fates, regulated by transcription factors and epigenetic modulators. Several models have been proposed to explain the differentiation of CTLs, although none fully recapitulate the experimental evidence. In this review article, we will summarize the latest research on the epigenetic regulation of CTL differentiation as well as provide a combined model that contemplates them.
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Diferenciación Celular/genética , Epigénesis Genética/inmunología , Memoria Inmunológica , Modelos Genéticos , Linfocitos T Citotóxicos/inmunología , Animales , Diferenciación Celular/inmunología , Heterogeneidad Genética , Humanos , Activación de Linfocitos , Factores de Transcripción/metabolismoRESUMEN
The transcriptional and epigenetic regulation of CD8+ T cell differentiation is critical for balancing pathogen eradication and long-term immunity by effector and memory CTLs, respectively. In this study, we demonstrate that the lysine demethylase 6b (Kdm6b) is essential for the proper generation and function of effector CD8+ T cells during acute infection and tumor eradication. We found that cells lacking Kdm6b (by either T cell-specific knockout mice or knockdown using short hairpin RNA strategies) show an enhanced generation of memory precursor and early effector cells upon acute viral infection in a cell-intrinsic manner. We also demonstrate that Kdm6b is indispensable for proper effector functions and tumor protection, and that memory CD8+ T cells lacking Kdm6b displayed a defective recall response. Mechanistically, we identified that Kdm6b, through induction of chromatin accessibility in key effector-associated gene loci, allows for the proper generation of effector CTLs. Our results pinpoint the essential function of Kdm6b in allowing chromatin accessibility in effector-associated genes, and identify Kdm6b as a potential target for therapeutics in diseases with dysregulated effector responses.
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Linfocitos T CD8-positivos/inmunología , Cromatina/inmunología , Histona Demetilasas con Dominio de Jumonji/inmunología , Animales , Células Cultivadas , Cromatina/genética , Ratones , Ratones Endogámicos C57BL , Ratones TransgénicosRESUMEN
To identify the prevalence of geographic tongue in patients >18 years. A systematic literature review was performed in search of population-based observational studies. Searches were performed using five main databases: Embase, LILACS, PubMed, Scopus and Web of Science; and three gray literature sources: Google Scholar, ProQuest, and OpenGrey. In addition, a manual search in the reference list and consultation with experts on the topic studied were performed. Methodological quality was assessed using the Joanna Briggs Institute's checklist for prevalence studies. Ratio meta-analyses were performed using JAMOVI. Initially, 3046 studies were identified. After a two-phase selection, 11 studies were included for quantitative synthesis. Two studies were classified as of low methodological quality, five studies as of moderate quality, and four as of high quality. Two types of prevalence were analyzed: by period and point. Three studies were included in the period prevalence meta-analysis, and the prevalence was 3% (Confidence interval [CI]: 0.4%-5.5%, n = 9813). Eight studies were included in the point-prevalence meta-analysis, and the prevalence was 3% (CI: -0.2% to 5.5%, n = 10,967). Although there are phases of exacerbation and remission in geographic tongue, prevalence and period prevalence were similar. Approximately one in 30 adults has a geographic tongue.
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Glositis Migratoria Benigna , Humanos , Adulto , Prevalencia , Estudios TransversalesRESUMEN
OBJECTIVE: To quantify the shear velocity and stiffness of the median nerve (MN) with shear wave elastography (SWE) at the carpal tunnel entrance and determine whether SWE is useful for diagnosing and staging carpal tunnel syndrome (CTS). MATERIALS AND METHODS: The study included 58 patients (79 wrists) with clinical and electroneuromyographic diagnoses of CTS and 55 healthy controls (63 wrists). MN shear velocity and stiffness were measured by SWE on the axial plane in both groups. The differences between CTS patients and controls and between different grades of CTS based on electrodiagnostic tests were studied using Student's t test and ANOVA with ROC analysis. RESULTS: The mean MN shear velocity and stiffness were significantly greater in CTS patients (2.5 ± 0.37 m/s and 19.4 ± 5.8 kPa) than in controls (1.91 ± 0.24 m/s and 11.1 ± 3.0 kPa) (p < 0.001) and greater in the severe CTS group (2.69 ± 0.39 m/s and 22.4 ± 7.1 kPa) than in the mild CTS group (2.37 ± 0.35 m/s and 17.3 ± 4,8 kPa). The cutoff value for the shear velocity was 2.13 m/s, with 86% and 82% sensitivity and specificity, respectively, and the cutoff value for stiffness was 13.6 kPa, with 87% and 82% sensitivity and specificity. CONCLUSION: MN shear velocity and stiffness are significantly higher in CTS patients. SWE can be used to diagnose CTS and distinguish between patients with mild and severe disease.
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Síndrome del Túnel Carpiano , Diagnóstico por Imagen de Elasticidad , Humanos , Síndrome del Túnel Carpiano/diagnóstico por imagen , Nervio Mediano/diagnóstico por imagen , Muñeca/diagnóstico por imagen , Sensibilidad y EspecificidadRESUMEN
The supplementation of dairy cows with tannins can reduce the ruminal degradation of dietary protein and urine N excretion, but high concentration in the diet can impair ruminal function, diet digestibility, feed intake, and milk yield. This study evaluated the effect of low concentrations (0, 0.14, 0.29, or 0.43% of diet in DM basis) of a tannin extract from the bark of Acacia mearnsii (TA) on milking performance, dry matter intake (DMI), digestibility, chewing behavior, ruminal fermentation, and N partition of dairy cows. Twenty Holstein cows (34.7 ± 4.8 kg/d, 590 ± 89 kg, and 78 ± 33 d in lactation) were individually fed a sequence of 4 treatments in 5, 4 × 4 Latin squares (with 21-d treatment periods, each with a 14-d adaptation period). The TA replaced citrus pulp in the total mixed ration and other feed ingredients were kept constant. Diets had 17.1% crude protein, mostly from soybean meal and alfalfa haylage. The TA had no detected effect on DMI (22.1 kg/d), milk yield (33.5 kg/d), and milk components. The proportions in milk fat of mixed origin fatty acids (16C and 17C) and the daily secretion of unsaturated fatty acids were linearly reduced and the proportion of de novo fatty acids was increased by TA. Cows fed TA had linear increase in the molar proportion of butyrate and linear reduction in propionate in ruminal fluid, whereas acetate did not differ. There was a tendency for the ratio of acetate to propionate to be linearly increased by TA. Cows fed TA had a linear reduction in the relative ruminal microbial yield, estimated by the concentrations of allantoin and creatinine in urine and body weight. The total-tract apparent digestibility of neutral detergent fiber, starch, and crude protein also did not differ. The TA induced a linear increase in meal size and duration of the first daily meal and reduced meal frequency. Rumination behavior did not differ with treatment. Cows fed 0.43% TA selected against feed particles >19 mm in the morning. There were tendencies for linear decreases in milk urea N (16.1-17.3 mg/dL), urine N (153-168 g/d and 25.5-28.7% of N intake), and plasma urea N at 6, 18, and 21 h postmorning feeding, and plasma urea N 12 h postfeeding was reduced by TA. The proportion of N intake in milk (27.1%) and feces (21.4%) did not differ with treatment. Reductions in urine N excretion and milk and plasma urea N suggest that TA reduced ruminal AA deamination, whereas lactation performance did not differ. Overall, TA up to 0.43% of DM did not affect DMI and lactation performance, while there was a tendency to reduce urine N excretion.
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Acacia , Femenino , Bovinos , Animales , Acacia/metabolismo , Taninos/farmacología , Propionatos/metabolismo , Masticación , Fermentación , Nitrógeno/metabolismo , Alimentación Animal/análisis , Digestión , Leche/metabolismo , Dieta/veterinaria , Lactancia , Ácidos Grasos/metabolismo , Extractos Vegetales/farmacología , Rumen/metabolismoRESUMEN
BACKGROUND AND AIMS: The dysgranula parts of the posterior insular cortex (PIC) stimulation (PICS) has been investigated as a new putative cortical target for nonpharmacologic therapies in patients with chronic and neuropathic pain (NP). This work investigates the neural bases of insula neurostimulation-induced antinociception and glutamatergic neurochemical mechanisms recruited by the PICS in animals with neuropathy. MATERIALS AND METHODS: Male Wistar rats were submitted to the von Frey and acetone tests to assess mechanical and cold allodynia after 21 days of chronic constriction injury (CCI) of the sciatic nerve or Sham procedure ("false operated"). Either the Cascade Blue 3000 MW lysine-fixable dextran (CBD) or the biotinylated dextran amine 3000 MW (BDA) neural tract tracer was microinjected into the PIC. The electrical PICS was performed at a low frequency (20 µA, 100 Hz) for 15 seconds by a deep brain stimulation device. PIC N-methyl-D-aspartate (NMDA) receptors (NMDAR) blockade with the selective antagonist LY235959 (at 2, 4, and 8 nmol/200 nL) followed by PICS was investigated in rats with CCI. RESULTS: PIC sends projections to the caudal pontine reticular nucleus, alpha part of the parvicellular reticular nucleus, dorsomedial tegmental area, and secondary somatosensory cortex (S2). PICS decreased both mechanical and cold allodynia in rats with chronic NP. Blockade of NMDAR in the PIC with LY235959 at 8 nmol attenuated PICS-produced antinociception. CONCLUSION: Neuroanatomic projections from the PIC to pontine reticular nuclei and S2 may contribute to chronic NP signaling. PICS attenuates the chronic NP, and the NMDA glutamatergic system in the PIC may be involved in PICS-induced antinociception in rodents with NP conditions.
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N-Metilaspartato , Neuralgia , Humanos , Ratas , Masculino , Animales , N-Metilaspartato/uso terapéutico , Hiperalgesia/terapia , Corteza Insular , Ratas Wistar , Neuralgia/tratamiento farmacológico , Receptores de N-Metil-D-Aspartato/metabolismo , Receptores de N-Metil-D-Aspartato/uso terapéuticoRESUMEN
Eucalypts are cultivated worldwide, but little is known about their status as hosts of root-knot nematodes (RKN) (Meloidogyne spp.). Moreover, information is scarce regarding the nature of the damage caused by RKN to eucalypt seedlings and trees. To investigate these aspects, we separately inoculated Meloidogyne enterolobii, M. javanica and M. incognita in seedlings of the world's most cultivated eucalypts: Eucalyptus dunni, E. grandis, E. cloeziana, E. camaldulensis, E. saligna, Corymbia citriodora, and the hybrid E. grandis × E. urophylla. After six months of greenhouse cultivation, we assessed nematode reproduction and variables that expressed the seedlings' shoot and root growth. We observed a diverse pattern of host statuses to RKN among the eucalypts, and all three Meloidogyne species reduced (p < 0.05) the root system mass, volume and length of E. grandis, E. saligna and the hybrid E. grandis × E. urophylla. Our results reaffirm previous reports indicating that RKN can delay the growth of seedlings in nurseries, who should thus adopt appropriate sanitary measures to avoid RKN establishment and spread. Moreover, the damage caused by RKN to eucalypts after just six months of cultivation suggests that the growth of eucalypt trees may be affected over the course of several years of cultivation.