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1.
Plant J ; 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38963754

RESUMEN

DNA glycosylases initiate the base excision repair (BER) pathway by catalyzing the removal of damaged or mismatched bases from DNA. The Arabidopsis DNA glycosylase methyl-CpG-binding domain protein 4 like (MBD4L) is a nuclear enzyme triggering BER in response to the genotoxic agents 5-fluorouracil and 5-bromouracil. To date, the involvement of MBD4L in plant physiological processes has not been analyzed. To address this, we studied the enzyme functions in seeds. We found that imbibition induced the MBD4L gene expression by generating two alternative transcripts, MBD4L.3 and MBD4L.4. Gene activation was stronger in aged than in non-aged seeds. Seeds from mbd4l-1 mutants displayed germination failures when maintained under control or ageing conditions, while 35S:MBD4L.3/mbd4l-1 and 35S:MBD4L.4/mbd4l-1 seeds reversed these phenotypes. Seed nuclear DNA repair, assessed by comet assays, was exacerbated in an MBD4L-dependent manner at 24 h post-imbibition. Under this condition, the BER genes ARP, APE1L, and LIG1 showed higher expression in 35S:MBD4L.3/mbd4l-1 and 35S:MBD4L.4/mbd4l-1 than in mbd4l-1 seeds, suggesting that these components could coordinate with MBD4L to repair damaged DNA bases in seeds. Interestingly, the ATM, ATR, BRCA1, RAD51, and WEE1 genes associated with the DNA damage response (DDR) pathway were activated in mbd4l-1, but not in 35S:MBD4L.3/mbd4l-1 or 35S:MBD4L.4/mbd4l-1 seeds. These results indicate that MBD4L is a key enzyme of a BER cascade that operates during seed imbibition, whose deficiency would cause genomic damage detected by DDR, generating a delay or reduction in germination.

2.
Plant J ; 115(6): 1633-1646, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37278489

RESUMEN

DNA glycosylases remove mispaired or modified bases from DNA initiating the base excision repair (BER) pathway. The DNA glycosylase MBD4 (methyl-CpG-binding domain protein 4) has been functionally characterized in mammals, but not yet in plants, where it is called MBD4-like (MBD4L). Mammalian MBD4 and Arabidopsis recombinant MBD4L excise U and T mispaired with G, as well as 5-fluorouracil (5-FU) and 5-bromouracil (5-BrU) in vitro. Here, we investigate the ability of Arabidopsis MBD4L to remove some of these substrates from the nuclear genome in vivo in coordination with uracil DNA glycosylase (AtUNG). We found that mbd4l mutants are hypersensitive to 5-FU and 5-BrU, as they displayed smaller size, less root growth, and higher cell death than control plants in both media. Using comet assays, we determined BER-associated DNA fragmentation in isolated nuclei and observed reduced DNA breaks in mbd4l plants under both conditions, but particularly with 5-BrU. The use of ung and ung x mbd4l mutants in these assays indicated that both MBD4L and AtUNG trigger nuclear DNA fragmentation in response to 5-FU. Consistently, we here report the nuclear localization of AtUNG based on the expression of AtUNG-GFP/RFP constructs in transgenic plants. Interestingly, MBD4L and AtUNG are transcriptionally coordinated but display not completely overlapping functions. MBD4L-deficient plants showed reduced expression of BER genes and enhanced expression of DNA damage response (DDR) gene markers. Overall, our findings indicate that Arabidopsis MBD4L is critical for maintaining nuclear genome integrity and preventing cell death under genotoxic stress conditions.


Asunto(s)
Arabidopsis , Animales , Arabidopsis/genética , Arabidopsis/metabolismo , ADN/metabolismo , Daño del ADN , Reparación del ADN/genética , Fluorouracilo/metabolismo , Mamíferos/genética , Mamíferos/metabolismo , Uracil-ADN Glicosidasa/genética , Uracil-ADN Glicosidasa/metabolismo
3.
J Chem Phys ; 158(24)2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37358222

RESUMEN

A new approach for generating Gaussian basis sets is reported and tested for atoms from H to Ne. The basis sets thus calculated, named SIGMA basis sets, range from DZ to QZ sizes and have the same composition per shell as Dunning basis sets but with different treatment of the contractions. The standard SIGMA basis sets and their augmented versions have proven to be very suitable for providing good results in atomic and molecular calculations. The performance of the new basis sets is analyzed in terms of total, correlation, and atomization energies, equilibrium distances, and vibrational frequencies in several molecules, and the results are compared at several computational levels with those obtained with the corresponding Dunning and other basis sets.

4.
J Chem Phys ; 158(1): 014104, 2023 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-36610956

RESUMEN

The Hellmann-Feynman (HF) theorem provides a way to compute forces directly from the electron density, enabling efficient force calculations for large systems through machine learning (ML) models for the electron density. The main issue holding back the general acceptance of the HF approach for atom-centered basis sets is the well-known Pulay force which, if naively discarded, typically constitutes an error upward of 10 eV/Å in forces. In this work, we demonstrate that if a suitably augmented Gaussian basis set is used for density functional calculations, the Pulay force can be suppressed, and HF forces can be computed as accurately as analytical forces with state-of-the-art basis sets, allowing geometry optimization and molecular dynamics to be reliably performed with HF forces. Our results pave a clear path forward for the accurate and efficient simulation of large systems using ML densities and the HF theorem.

5.
Int Orthop ; 47(2): 447-456, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35849162

RESUMEN

PURPOSE: Over 4.83 million spine surgery procedures are performed annually around the world. With the considerable caseload and the precision needed to achieve optimal spinal instrumentation, technical progress has helped to improve the technique's safety and accuracy with the development of peri-operative assistance tools. Contrary to other surgical applications already part of the standard of care, the development of robotics in spine surgery is still a novelty and is not widely available nor used. Robotics, especially when coupled with other guidance modalities such as navigation, seems to be a promising tool in our quest for accuracy, improving patient outcomes and reducing surgical complications. Robotics in spine surgery may also be for the surgeon a way to progress in terms of ergonomics, but also to respond to a growing concern among surgical teams to reduce radiation exposure. METHOD: We present in this recent systematic review of the literature realized according to the PRISMA guidelines the place of robotics in spine surgery, reviewing the comparison to standard techniques, the current and future indications, the learning curve, the impact on radiation exposure, and the cost-effectiveness. RESULTS: Seventy-six relevant original studies were identified and analyzed for the review. CONCLUSION: Robotics has proved to be a safe help for spine surgery, both for the patient with a decrease of operating time and increase in pedicular screw accuracy, and for the surgical team with a decrease of radiation exposure. Medico-economic studies demonstrated that despite a high buying cost, the purchase of a robot dedicated for spine surgery is cost-effective resulting in lesser revision, lower infection, reduced length of stay, and shorter surgical procedure.


Asunto(s)
Tornillos Pediculares , Robótica , Fusión Vertebral , Cirujanos , Cirugía Asistida por Computador , Humanos , Tornillos Óseos , Procedimientos Neuroquirúrgicos , Robótica/métodos , Fusión Vertebral/métodos , Columna Vertebral/cirugía , Cirugía Asistida por Computador/métodos
6.
Eur Respir J ; 58(3)2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33574074

RESUMEN

BACKGROUND: Lung ultrasound is feasible for assessing lung injury caused by coronavirus disease 2019 (COVID-19). However, the prognostic meaning and time-line changes of lung injury assessed by lung ultrasound in COVID-19 hospitalised patients are unknown. METHODS: Prospective cohort study designed to analyse prognostic value of lung ultrasound in COVID-19 patients by using a quantitative scale (lung ultrasound Zaragoza (LUZ)-score) during the first 72 h after admission. The primary end-point was in-hospital death and/or admission to the intensive care unit. Total length of hospital stay, increase of oxygen flow and escalation of medical treatment during the first 72 h were secondary end-points. RESULTS: 130 patients were included in the final analysis; mean±sd age was 56.7±13.5 years. Median (interquartile range) time from the beginning of symptoms to admission was 6 (4-9) days. Lung injury assessed by LUZ-score did not differ during the first 72 h (21 (16-26) points at admission versus 20 (16-27) points at 72 h; p=0.183). In univariable logistic regression analysis, estimated arterial oxygen tension/inspiratory oxygen fraction ratio (PAFI) (hazard ratio 0.99, 95% CI 0.98-0.99; p=0.027) and LUZ-score >22 points (5.45, 1.42-20.90; p=0.013) were predictors for the primary end-point. CONCLUSIONS: LUZ-score is an easy, simple and fast point-of-care ultrasound tool to identify patients with severe lung injury due to COVID-19, upon admission. Baseline score is predictive of severity along the whole period of hospitalisation. The score facilitates early implementation or intensification of treatment for COVID-19 infection. LUZ-score may be combined with clinical variables (as estimated by PAFI) to further refine risk stratification.


Asunto(s)
COVID-19 , Sistemas de Atención de Punto , Adulto , Anciano , Mortalidad Hospitalaria , Humanos , Pulmón/diagnóstico por imagen , Persona de Mediana Edad , Estudios Prospectivos , Medición de Riesgo , SARS-CoV-2
7.
Am J Physiol Renal Physiol ; 318(5): F1188-F1198, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-32249611

RESUMEN

Caloric restriction (CR) is known to have multiple beneficial effects on health and longevity. To study the effect of CR on phosphorus metabolism and vascular calcification (VC), rats were fed normal or restricted calories (67% of normal). The phosphorus content of the diets was adjusted to provide equal phosphorus intake independent of the calories ingested. After 50 days of CR, rats had negative phosphorus balance, lower plasma phosphorus, glucose, triglycerides, and leptin, and higher adiponectin than rats fed normal calories. Uremia was induced by 5/6 nephrectomy (Nx). After Nx, rats were treated with calcitriol (80 ng/kg ip every other day) and high-phosphorus diets (1.2% and 1.8%). No differences in aortic calcium content were observed between rats that ate normal or restricted calories before Nx in either rats that received 1.2% phosphorus (11.5 ± 1.7 vs. 10.9 ± 2.1 mg/g tissue) or in rats that received 1.8% phosphorus (12.5 ± 2.3 vs. 12.0 ± 2.9 mg/g of tissue). However, mortality was significantly increased in rats subjected to CR before Nx in both the 1.2% phosphorus groups (75% vs. 25%, P = 0.019) and 1.8% phosphorus groups (100% vs. 45%, P < 0.001). After calcitriol administration was stopped and phosphorus intake was normalized, VC regressed rapidly, but no significant differences in aortic calcium were detected between rats that ate normal or restricted calories during the regression phase (5.7 ± 2.7 and 5.2 ± 1.5 mg/g tissue). In conclusion, CR did not prevent or ameliorate VC and increased mortality in uremic rats.


Asunto(s)
Aorta/metabolismo , Enfermedades de la Aorta/prevención & control , Restricción Calórica , Riñón/metabolismo , Fósforo Dietético/metabolismo , Uremia/dietoterapia , Calcificación Vascular/prevención & control , Animales , Aorta/patología , Enfermedades de la Aorta/etiología , Enfermedades de la Aorta/metabolismo , Enfermedades de la Aorta/patología , Calcitriol , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Metabolismo Energético , Femenino , Factores de Crecimiento de Fibroblastos/sangre , Glucuronidasa/metabolismo , Riñón/patología , Proteínas Klotho , Nefrectomía , Ratas Wistar , Factores de Tiempo , Uremia/etiología , Uremia/metabolismo , Calcificación Vascular/etiología , Calcificación Vascular/metabolismo , Calcificación Vascular/patología
8.
Kidney Int ; 95(5): 1064-1078, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30878213

RESUMEN

Calcimimetics decrease parathyroid hormone (PTH) secretion in patients with secondary hyperparathyroidism. The decrease in PTH should cause a reduction in bone turnover; however, the direct effect of calcimimetics on bone cells, which express the calcium-sensing receptor (CaSR), has not been defined. In this study, we evaluated the direct bone effects of CaSR activation by a calcimimetic (AMG 641) in vitro and in vivo. To create a PTH "clamp," total parathyroidectomy was performed in rats with and without uremia induced by 5/6 nephrectomy, followed by a continuous subcutaneous infusion of PTH. Animals were then treated with either the calcimimetic or vehicle. Calcimimetic administration increased osteoblast number and osteoid volume in normal rats under a PTH clamp. In uremic rats, the elevated PTH concentration led to reduced bone volume and increased bone turnover, and calcimimetic administration decreased plasma PTH. In uremic rats exposed to PTH at 6-fold the usual replacement dose, calcimimetic administration increased osteoblast number, osteoid surface, and bone formation. A 9-fold higher dose of PTH caused an increase in bone turnover that was not altered by the administration of calcimimetic. In an osteosarcoma cell line, the calcimimetic induced Erk1/2 phosphorylation and the expression of osteoblast genes. The addition of a calcilytic resulted in the opposite effect. Moreover, the calcimimetic promoted the osteogenic differentiation and mineralization of human bone marrow mesenchymal stem cells in vitro. Thus, calcimimetic administration has a direct anabolic effect on bone that counteracts the decrease in PTH levels.


Asunto(s)
Compuestos de Bifenilo/administración & dosificación , Remodelación Ósea/efectos de los fármacos , Calcimiméticos/administración & dosificación , Hiperparatiroidismo Secundario/tratamiento farmacológico , Fallo Renal Crónico/complicaciones , Fenetilaminas/administración & dosificación , Animales , Modelos Animales de Enfermedad , Humanos , Hiperparatiroidismo Secundario/sangre , Hiperparatiroidismo Secundario/etiología , Masculino , Osteoblastos/efectos de los fármacos , Hormona Paratiroidea/administración & dosificación , Hormona Paratiroidea/sangre , Hormona Paratiroidea/metabolismo , Ratas , Ratas Wistar , Receptores Sensibles al Calcio/metabolismo
10.
Eur Radiol ; 28(7): 2934-2941, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29387922

RESUMEN

OBJECTIVES: To review the diagnostic accuracy of ultrasound-guided core-needle biopsy (CNB) in the diagnosis of salivary gland tumours (SGT). METHODS: Retrospective, institutional review board approved, analysis of the CNB of SGT performed at our centre in 8 years. We used an automatic 18-G spring-loaded device. The final diagnosis was based on surgery in the cases that were operated on, and on clinical evolution and biopsy findings in the rest. RESULTS: Four hundred and nine biopsies were performed in 381 patients (ages, 2-97 years; mean, 55.9). There were two minor complications. Biopsy was diagnostic in 98.3%. There were eight false negatives. The diagnostic values for malignancy were: sensitivity 89.6%, specificity 100%, positive predictive value (PPV) 100% and negative predictive value (NPV) 98%. For the detection of neoplasms were: sensitivity 98.7%, specificity 99%, PPV 99.7% and VPN 96.1%. CONCLUSIONS: Accuracy of CNB in SGT is very high, with a very high sensitivity and an absolutely reliable diagnosis of malignancy. Complication rate is very low. It should be considered the technique of choice when a STG is detected. Normal tissue results warrant repeating biopsy. KEY POINTS: • Ultrasound-guided core-biopsy is the technique of choice in salivary glands nodules • Sensitivity, specificity for detecting neoplasms (which should be resected) are around 99% • Diagnosis of malignancy in core-biopsy is absolutely reliable • A CNB result of "normal tissue", however, warrants repeating the biopsy • Complication rate is very low.


Asunto(s)
Neoplasias de las Glándulas Salivales/diagnóstico por imagen , Neoplasias de las Glándulas Salivales/patología , Ultrasonografía Intervencional/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biopsia con Aguja Gruesa/métodos , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Humanos , Biopsia Guiada por Imagen/métodos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Glándulas Salivales/diagnóstico por imagen , Glándulas Salivales/patología , Sensibilidad y Especificidad , Adulto Joven
11.
Kidney Int ; 92(5): 1084-1099, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28760336

RESUMEN

Although magnesium has been shown to prevent vascular calcification in vitro, controlled in vivo studies in uremic animal models are limited. To determine whether dietary magnesium supplementation protects against the development of vascular calcification, 5/6 nephrectomized Wistar rats were fed diets with different magnesium content increasing from 0.1 to 1.1%. In one study we analyzed bone specimens from rats fed 0.1%, 0.3%, and 0.6% magnesium diets, and in another study we evaluated the effect of intraperitoneal magnesium on vascular calcification in 5/6 nephrectomized rats. The effects of magnesium on established vascular calcification were also evaluated in uremic rats fed on diets with either normal (0.1%) or moderately increased magnesium (0.6%) content. The increase in dietary magnesium resulted in a marked reduction in vascular calcification, together with improved mineral metabolism and renal function. Moderately elevated dietary magnesium (0.3%), but not high dietary magnesium (0.6%), improved bone homeostasis as compared to basal dietary magnesium (0.1%). Results of our study also suggested that the protective effect of magnesium on vascular calcification was not limited to its action as an intestinal phosphate binder since magnesium administered intraperitoneally also decreased vascular calcification. Oral magnesium supplementation also reduced blood pressure in uremic rats, and in vitro medium magnesium decreased BMP-2 and p65-NF-κB in TNF-α-treated human umbilical vein endothelial cells. Finally, in uremic rats with established vascular calcification, increasing dietary magnesium from 0.1% magnesium to 0.6% reduced the mortality rate from 52% to 28%, which was associated with reduced vascular calcification. Thus, increasing dietary magnesium reduced both vascular calcification and mortality in uremic rats.


Asunto(s)
Huesos/metabolismo , Suplementos Dietéticos , Magnesio/administración & dosificación , Fosfatos/metabolismo , Uremia/complicaciones , Calcificación Vascular/dietoterapia , Animales , Quelantes/administración & dosificación , Modelos Animales de Enfermedad , Células Endoteliales de la Vena Umbilical Humana , Humanos , Magnesio/sangre , Masculino , Nefrectomía , Ratas , Ratas Wistar , Uremia/sangre , Uremia/dietoterapia , Calcificación Vascular/sangre , Calcificación Vascular/mortalidad
12.
BMC Nephrol ; 18(1): 374, 2017 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-29281993

RESUMEN

BACKGROUND: High fat diets are implicated in the pathogenesis of metabolic syndrome, obesity and renal disease. Previous studies have revealed that high fat diets promote vascular calcification in uremic rats. Moreover, vitamin E has been shown to prevent uremic calcifications in genetically obese Zucker rats fed standard diet. The objective of this study was to investigate the influence of vitamin E supplementation on the development of extraskeletal calcifications in non-obese (wild type) uremic rats fed high fat diets. METHODS: Wistar rats (n = 32) were preconditioned by feeding either a normal (NF) or high fat (HF) diet for 45 days and subsequently were subjected to 5/6 nephrectomy (Nx). Just before performing the first Nx step, a blood sample (Pre-Nx) was obtained. After Nx rats were switched to a diet with 0.9% phosphorus and supplemented with calcitriol. Also, after Nx, half of the rats from each group (NF and HF) were treated with vitamin E (VitE) in the diet (30,000 mg/kg) and the other half were maintained on basic VitE requirements (27 mg/kg). Thus, rats were allotted to four experimental groups: Nx-NF (n = 8), Nx-NF-VitE (n = 8), Nx-HF (n = 8) and Nx-HF-VitE (n = 8). At the time of sacrifice (day 66), blood and tissue samples were obtained. RESULTS: Feeding a HF diet for 45 days did not increase body weight but elicited hyperglycemia, hypertriglyceridemia, an increase in plasma fibroblast growth factor 23 and a reduction in plasma calcitriol concentrations. After Nx, rats fed HF diet showed substantial extraskeletal calcification with aortic calcium content that was higher than in rats fed NF diet. Supplementation with VitE significantly (p < 0.05) reduced aortic (from 38.4 ± 8.8 to 16.5 ± 1.4 mg/g), gastric (from 5.6 ± 2.7 to 1.2 ± 0.4 mg/g) and pulmonary (from 1.8 ± 0.3 to 0.3 ± 0.2 mg/g) calcium content in rats on HF diets. CONCLUSIONS: Uremic rats fed HF diets developed more severe extraosseous calcifications than their normocaloric-fed counterparts and dietary VitE supplementation protected against uremic calcifications in rats fed HF diets. Thus, eating energy-rich foods should be discouraged in patients with renal disease and their deleterious effect may be ameliorated with adequate antioxidant supply.


Asunto(s)
Dieta Alta en Grasa/efectos adversos , Uremia/tratamiento farmacológico , Calcificación Vascular/prevención & control , Vitamina E/uso terapéutico , Animales , Antioxidantes/uso terapéutico , Ratas , Ratas Wistar , Uremia/etiología , Uremia/patología , Calcificación Vascular/etiología , Calcificación Vascular/patología
13.
Am J Med Genet A ; 170(3): 734-42, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26640227

RESUMEN

Autosomal-dominant brachydactyly type E is a congenital limb malformation characterized by small hands and feet as a result of shortened metacarpals and metatarsals. Alterations that predict haploinsufficiency of PTHLH, the gene coding for parathyroid hormone related protein (PTHrP), have been identified as a cause of this disorder in seven families. Here, we report three patients affected with brachydactyly type E, caused by PTHLH mutations expected to result in haploinsufficiency, and discuss our data compared to published reports.


Asunto(s)
Braquidactilia/diagnóstico , Braquidactilia/genética , Mutación , Proteína Relacionada con la Hormona Paratiroidea/genética , Adulto , Huesos/diagnóstico por imagen , Huesos/patología , Niño , Femenino , Sitios Genéticos , Humanos , Linaje , Fenotipo , Sitios de Empalme de ARN , Eliminación de Secuencia
14.
Am J Physiol Renal Physiol ; 309(7): F638-47, 2015 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-26246512

RESUMEN

This study describes fiber-type adaptations in hindlimb muscles, the interaction of sex, and the role of hypoxia on this response in 12-wk ⅚ nephrectomized rats (Nx). Contractile, metabolic, and morphological features of muscle fiber types were assessed in the slow-twitch soleus and the fast-twitch tibialis cranialis muscles of Nx rats, and compared with sham-operated controls. Rats of both sexes were considered in both groups. A slow-to-fast fiber-type transformation occurred in the tibialis cranialis of Nx rats, particularly in males. This adaptation was accomplished by impaired oxidative capacity and capillarity, increased glycolytic capacity, and no changes in size and nuclear density of muscle fiber types. An oxidative-to-glycolytic metabolic transformation was also found in the soleus muscle of Nx rats. However, a modest fast-to-slow fiber-type transformation, fiber hypertrophy, and nuclear proliferation were observed in soleus muscle fibers of male, but not of female, Nx rats. Serum testosterone levels decreased by 50% in male but not in female Nx rats. Hypoxia-inducible factor-1α protein level decreased by 42% in the tibialis cranialis muscle of male Nx rats. These data demonstrate that 12 wk of Nx induces a muscle-specific adaptive response in which myofibers do not change (or enlarge minimally) in size and nuclear density, but acquire markedly different contractile and metabolic characteristics, which are accompanied by capillary rarefaction. Muscle function and sex play relevant roles in these adaptations.


Asunto(s)
Miembro Posterior/citología , Miembro Posterior/fisiología , Fibras Musculares de Contracción Rápida/fisiología , Fibras Musculares de Contracción Lenta/fisiología , Nefrectomía , Animales , Peso Corporal/fisiología , Capilares/citología , Capilares/fisiología , Ingestión de Alimentos/fisiología , Femenino , Gliceraldehído-3-Fosfato Deshidrogenasas/metabolismo , Hipoxia/patología , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Pruebas de Función Renal , Masculino , Fibras Musculares de Contracción Rápida/ultraestructura , Fibras Musculares de Contracción Lenta/ultraestructura , Cadenas Pesadas de Miosina/metabolismo , Tamaño de los Órganos/fisiología , Ratas , Ratas Wistar , Caracteres Sexuales , Succinato Deshidrogenasa/metabolismo , Testosterona/metabolismo , Uremia/patología
15.
J Vet Intern Med ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38946311

RESUMEN

BACKGROUND: Little information exists about vitamin D status in bitches with mammary tumors. OBJECTIVES: To determine whether low plasma vitamin D concentrations are found in bitches with mammary tumors. ANIMALS: Eighty-five client-owned bitches with mammary tumors (n = 21 benign, n = 64 malignant) and 39 age-matched healthy bitches. METHODS: Case-control study. Plasma ionized and total calcium, phosphorus, magnesium, urea, creatinine, albumin, total proteins, alanine aminotransferase, alkaline phosphatase, parathyroid hormone (PTH), calcitriol (1,25-dihydroxyvitamin D), and 25-hydroxyvitamin D concentrations were measured in all bitches at the time of clinical diagnosis and before any treatments. Statistical analysis was performed to compare variables among groups (control, benign, and malignant). RESULTS: No significant differences were found when plasma 25-hydroxyvitamin D concentrations in bitches with malignant (148.9 [59.9] ng/mL) and benign mammary tumors (150.1 [122.3] ng/mL) were compared with control group (129.9 [54.5] ng/mL). Parathyroid hormone was significantly higher in bitches with malignant (19.9 [20.5] pg/mL), and benign mammary tumors (14.6 [14.9] pg/mL) compared with control group (7.5 [7.5] pg/mL; P < .01). Only the presence of mammary tumors (P < .01) and age (P = .04; adjusted R2 = .22) was significant in predicting PTH. CONCLUSIONS: Bitches with mammary tumors do not have low 25-hydroxyvitamin D concentrations thus vitamin D supplementation is unlikely to be useful for prevention of mammary tumors in bitches.

16.
Front Plant Sci ; 15: 1380738, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38863550

RESUMEN

Nitrogen (N) and phosphorus (P) fertilizers change the morphological structure and effectiveness of P in the soil, which in turn affects crop growth, yield, and quality. However, the effects and mechanism of combined N and P application on the content of P fractions and the transformation of effective forms in alfalfa (Medicago sativa L.) production is unclear. This experiment was conducted with four levels of N: 0 (N0), 60 (N1), 120 (N2) and 180 kg·ha-1 (N3); and two levels of P (P2O5): 0 (P0) and 100 kg·ha-1 (P1). The results indicated that, under the same N level, P application significantly increased soil total N, and total P, available P, and content of various forms of inorganic P when compared to no P application, while decreasing the content of various forms of organic P and pH value. In general, under P0 conditions, soil total N content tended to increase with increasing N application, while total P, available P content, pH, inorganic P content in all forms, and organic P content in all forms showed a decreasing trend. When compared to no N application, insoluble P (Fe-P, O-P, Ca10-P) of the N application treatments was reduced 2.80 - 22.72, 2.96 - 20.42, and 5.54 - 20.11%, respectively. Under P1 conditions, soil total N and O-P tended to increase with increasing N application, while, pH, Ca2-P, Al-P, Fe-P, Ca10-P, and organic P content of each form tended to decrease. Total P, available P, and labile organic P (LOP) of N application reduced 0.34 - 8.58, 4.76 - 19.38, and 6.27 - 14.93%, respectively, when compared to no application. Nitrogen fertilization reduced the soil Ca2-P ratio, while P fertilization reduced soil Fe-P, moderately resistant organic P (MROP), and highly resistant P (HROP) ratios, and combined N and P elevated the Ca8-P to LOP ratio. The results of redundancy analysis showed that soil total N content, available P content, and pH were the key factors affecting the conversion of P fractions in the soil. Nitrogen and P reduced the proportion of soil insoluble P, promoted the activation of soil organic P, resulting in accumulation of slow-acting P in the soil, thereby improving the efficiency of soil P in alfalfa production.

17.
Pharmacol Biochem Behav ; 236: 173709, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38244863

RESUMEN

Physical activity (PA) is very beneficial for physical and mental health. This study aims to examine the resilience-inducting effect of PA in adult male Wistar rats exposed to unpredictable chronic mild stress (UCMS). Furthermore, we analyzed the influence of PA on behavioral tasks and functional brain connectivity with cytochrome c oxidase technique. The cytochrome c oxidase (CCO) is a mitochondrial enzyme involved in oxidative phosphorylation and ATP generation. For this analysis, we included five groups: Basal (n = 10, to determine the basal level of brain activity), Behav (n = 15, subjected exclusively to behavioral tests), PA (n = 10, exposed to physical activity), UCMS (n = 15, subjected to a stress protocol) and PA + UCMS (n = 15, exposed to PA prior to stress). The UCMS protocol consisted of randomly presenting several different stressors over four consecutive weeks. We evaluated several behaviors of the Behav, UCMS, and PA + UCMS groups. This assessment includes the hedonic responses using the sucrose consumption task, unconditioned anxiety with the zero maze, and coping strategies assessed with the cat odor test. The UCMS group showed an anhedonia profile and increased anxiety compared with the other groups. Although in the exposure to cat odor test, the PA + UCMS remained for the same time in the cat odor compartment as the other groups, it did not approach the odor, showing that it detected the risk. This response is more adaptive than the responses of the UCMS and Behav groups. An exploratory analysis of the cerebral connections showed an increase in CCO activity in the UCMS group compared to the other groups. This overactivity was reduced in dorsal Cornu Ammonis 3(dCA3) by prior PA. In this region, PA + UCMS showed similar activity as the groups not subjected to chronic stress. Therefore, PA can prevent the harmful effects of chronic stress on dCA3.


Asunto(s)
Citocromos c , Resiliencia Psicológica , Ratas , Animales , Masculino , Ratas Wistar , Complejo IV de Transporte de Electrones , Encéfalo , Estrés Psicológico , Depresión , Modelos Animales de Enfermedad
18.
J Clin Med ; 13(4)2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38398366

RESUMEN

BACKGROUND: Congestion is an essential issue in patients with heart failure (HF). Standard treatments do not usually achieve decongestion, and various strategies have been proposed to guide treatment, such as determination of natriuresis. After starting treatment with loop diuretics, we postulate that initial natriuresis might help treatment titration, decongestion, and improve prognosis. METHODS: It was a prospective and observational study. Patients admitted with the diagnosis of HF decompensation were eligible. An assessment of congestion was performed during the first 48 h. RESULTS: A total of 113 patients were included. A poor diuretic response was observed in 39.8%. After the first 48 h, patients with a greater diuretic response on admission (NaU > 80 mmol/L) showed fewer pulmonary b lines (12 vs. 15; p = 0.084), a lower IVC diameter (18 mm vs. 22 mm; p = 0.009), and lower IAP figures (11 mmHg vs. 13 mmHg; p = 0.041). Survival analysis tests demonstrated significant differences showing a higher proportion of all-cause mortality (ACM) and HF rehospitalization in the poor-diuretic-response group (log-rank test = 0.020). CONCLUSIONS: Up to 40% of the patients presented a poorer diuretic response at baseline, translating into worse outcomes. Patients with an optimal diuretic response showed significantly higher abdominal decongestion at 48 h and a better prognosis regarding ACM and/or HF rehospitalizations.

19.
J Am Soc Nephrol ; 23(7): 1190-7, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22581996

RESUMEN

Fibroblast growth factor (FGF) 23 inhibits calcitriol production, which could exacerbate calcium deficiency or hypocalcemia unless calcium itself modulates FGF23 in this setting. In Wistar rats with normal renal function fed a diet low in both calcium and vitamin D, the resulting hypocalcemia was associated with low FGF23 despite high parathyroid hormone (PTH) and high calcitriol levels. FGF23 correlated positively with calcium and negatively with PTH. Addition of high dietary phosphorus to this diet increased FGF23 except in rats with hypocalcemia despite high PTH levels. In parathyroidectomized rats, an increase in dietary calcium for 10 days increased serum calcium, with an associated increase in FGF23, decrease in calcitriol, and no change in phosphorus. Also in parathyroidectomized rats, FGF23 increased significantly 6 hours after administration of calcium gluconate. Taken together, these results suggest that hypocalcemia reduces the circulating concentrations of FGF23. This decrease in FGF23 could be a response to avoid a subsequent reduction in calcitriol, which could exacerbate hypocalcemia.


Asunto(s)
Calcio/deficiencia , Calcio/metabolismo , Factores de Crecimiento de Fibroblastos/sangre , Hipocalcemia/metabolismo , Animales , Calcitriol/metabolismo , Calcio/farmacología , Gluconato de Calcio/farmacología , Factores de Crecimiento de Fibroblastos/efectos de los fármacos , Masculino , Modelos Animales , Hormona Paratiroidea/metabolismo , Paratiroidectomía , Fósforo Dietético/farmacología , Ratas , Ratas Wistar , Vitamina D/metabolismo
20.
Vet Anaesth Analg ; 40(6): e40-7, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23782643

RESUMEN

OBJECTIVE: To evaluate clinical effects of romifidine and low doses of tiletamine-zolazepam (TZ) in dogs. STUDY DESIGN: Randomized "blinded" cross-over study. ANIMALS: Six healthy beagle dogs (two males, four females). METHODS: In separate preliminary experiments dogs received intravenous (IV) tiletamine-zolazepam (TZ) at 1 and 2 mg kg(-1). For the main trial, dogs received romifidine (R) followed 5 minutes later by IV at six dose regimens: R40TZ1, R60TZ1, R80TZ1 (Romifidine at 40, 60, 80 µg kg(-1) and TZ at 1 mg kg(-1)), R40TZ2, R60TZ2 and R80TZ2 (Romifidine at 40, 60, 80 µg kg(-1) and TZ at 2 mg kg(-1)). Dogs underwent endotracheal intubation, but breathed room air. Cardiorespiratory variables were measured and arterial blood analyzed. Quality of sedation, duration of anaesthesia and time to recovery (TR) were recorded. Data were analysed by anova or Friedman test as relevant. RESULTS: Endotracheal intubation was possible with all romifidine/TZ combinations but not with TZ alone. Mean times (minutes) from TZ injection to return of pedal reflex were 1-3 minutes for TZ alone, and 9-17 minutes for romifidine combinations. In the main trial (romifidine combinations) mean time (minutes) to standing increased with increasing dosage (R40TZ1 13; R80TZ2 32). Five minutes after TZ administration, when compared with baseline arterial blood pressures and arterial carbon dioxide had increased, and respiratory rate, pH and arterial oxygen tensions decreased, these changes becoming statistically significant with the higher dose rates. One dog in R60TZ2 and three dogs in R80TZ2 became hypoxaemic. CONCLUSIONS AND CLINICAL RELEVANCE: Romifidine improves the quality and lengthens the duration of anaesthesia induced by TZ. The combination provides a suitable protocol for induction of or short-term anaesthesia in healthy dogs. However, the higher doses cause cardiovascular stimulation and respiratory depression, and precautions should be taken accordingly.


Asunto(s)
Anestesia Intravenosa/veterinaria , Anestésicos Combinados , Perros , Imidazoles , Tiletamina , Zolazepam , Anestesia Intravenosa/métodos , Anestésicos , Anestésicos Disociativos , Animales , Ansiolíticos , Presión Sanguínea/efectos de los fármacos , Sedación Consciente/métodos , Sedación Consciente/veterinaria , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Masculino , Frecuencia Respiratoria/efectos de los fármacos
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