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The p53 family of proteins evolved from a common ancestor into three separate genes encoding proteins that act as transcription factors with distinct cellular roles. Isoforms of each member that lack specific regions or domains are suggested to result from alternative transcription start sites, alternative splicing or alternative translation initiation, and have the potential to exponentially increase the functional repertoire of each gene. However, evidence supporting the presence of individual protein variants at functional levels is often limited and is inferred by mRNA detection using highly sensitive amplification techniques. We provide a critical appraisal of the current evidence for the origins, expression, functions and regulation of p53-family isoforms. We conclude that despite the wealth of publications, several putative isoforms remain poorly established. Future research with improved technical approaches and the generation of isoform-specific protein detection reagents is required to establish the physiological relevance of p53-family isoforms in health and disease. In addition, our analyses suggest that p53-family variants evolved partly through convergent rather than divergent evolution from the ancestral gene.
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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.
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Proteínas de Arabidopsis , Arabidopsis , DNA Glicosilases , Reparo do DNA , Germinação , Sementes , Sementes/genética , Sementes/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , DNA Glicosilases/metabolismo , DNA Glicosilases/genética , Regulação da Expressão Gênica de Plantas , Dano ao DNARESUMO
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.
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Arabidopsis , Animais , Arabidopsis/genética , Arabidopsis/metabolismo , DNA/metabolismo , Dano ao DNA , Reparo do DNA/genética , Fluoruracila/metabolismo , Mamíferos/genética , Mamíferos/metabolismo , Uracila-DNA Glicosidase/genética , Uracila-DNA Glicosidase/metabolismoRESUMO
INTRODUCTION: There are conflicting reports about the effect or rapamycin on the kidneys. Rapamycin is known to promote phosphaturia that may be associated to renal injury. METHODS: Detailed histopathological studies were performed on the kidneys of rats with normal (Control) and reduced (Nx) renal mass that were treated with rapamycin (1.3 mg/kg for 22 days) or placebo. The effect of rapamycin was also evaluated in Control and Nx rats fed different amounts of phosphorus: 0.6% P (NP), 1.2% P (HP) and 0.2% P (LP). Quantitative scores of kidney lesions were obtained for: interstitial nephritis (IN), tubular damage (TD), and nephrocalcinosis (NC). RESULTS: When compared with placebo, rapamycin administration to Nx rats resulted in significant increases in IN (4.17±0.74 vs 1.51±0.53 %) and TD (14.45±1.51 vs 8.61±1.83 %). Rapamycin also increased NC both in Control (0.86±0.23 vs 0.14±0.06 %) and Nx (0.86±0.32 vs 0.15±0.14 %) rats. In Control rats receiving rapamycin, feeding HP aggravated IN (3.25±0.48 %), TD (22.47±4.56 %) and NC (3.66±0.75 %) while feeding LP prevented development of any renal lesions. In Nx rats treated with rapamycin, HP intake also increased IN (8.95±1.94 %), TD (26.86±3.95 %) and NC (2.77±0.60 %) whereas feeding LP reduced all lesions to lower levels than in rats fed NP. Rapamycin treatment increased fractional excretion of P (FEP) and an excellent correlation between scores for renal lesions and FEP was found. CONCLUSION: Rapamycin has deleterious effects on kidney pathology causing lesions that are located mainly at tubular and tubulo-interstitial level. Rapamycin-induced kidney damage is more evident in rats that already have decreased renal function and seems to be related to the phosphaturic effect of the drug. Dietary P restriction prevents kidney damage in rats treated with rapamycin.
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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.
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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.
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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.
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Parafusos Pediculares , Robótica , Fusão Vertebral , Cirurgiões , Cirurgia Assistida por Computador , Humanos , Parafusos Ósseos , Procedimentos Neurocirúrgicos , Robótica/métodos , Fusão Vertebral/métodos , Coluna Vertebral/cirurgia , Cirurgia Assistida por Computador/métodosRESUMO
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 72â 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 72â h were secondary end-points. RESULTS: 130 patients were included in the final analysis; mean±sd age was 56.7±13.5â 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 72â h (21 (16-26) points at admission versus 20 (16-27) points at 72â 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.
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COVID-19 , Sistemas Automatizados de Assistência Junto ao Leito , Adulto , Idoso , Mortalidade Hospitalar , Humanos , Pulmão/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos Prospectivos , Medição de Risco , SARS-CoV-2RESUMO
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.
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Aorta/metabolismo , Doenças da Aorta/prevenção & controle , Restrição Calórica , Rim/metabolismo , Fósforo na Dieta/metabolismo , Uremia/dietoterapia , Calcificação Vascular/prevenção & controle , Animais , Aorta/patologia , Doenças da Aorta/etiologia , Doenças da Aorta/metabolismo , Doenças da Aorta/patologia , Calcitriol , Modelos Animais de Doenças , Progressão da Doença , Metabolismo Energético , Feminino , Fatores de Crescimento de Fibroblastos/sangue , Glucuronidase/metabolismo , Rim/patologia , Proteínas Klotho , Nefrectomia , Ratos Wistar , Fatores de Tempo , Uremia/etiologia , Uremia/metabolismo , Calcificação Vascular/etiologia , Calcificação Vascular/metabolismo , Calcificação Vascular/patologiaRESUMO
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.
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Compostos de Bifenilo/administração & dosagem , Remodelação Óssea/efeitos dos fármacos , Calcimiméticos/administração & dosagem , Hiperparatireoidismo Secundário/tratamento farmacológico , Falência Renal Crônica/complicações , Fenetilaminas/administração & dosagem , Animais , Modelos Animais de Doenças , Humanos , Hiperparatireoidismo Secundário/sangue , Hiperparatireoidismo Secundário/etiologia , Masculino , Osteoblastos/efeitos dos fármacos , Hormônio Paratireóideo/administração & dosagem , Hormônio Paratireóideo/sangue , Hormônio Paratireóideo/metabolismo , Ratos , Ratos Wistar , Receptores de Detecção de Cálcio/metabolismoAssuntos
Proteínas de Arabidopsis , Arabidopsis , DNA Glicosilases , Processamento Alternativo/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , DNA Glicosilases/genética , DNA Glicosilases/metabolismo , Reparo do DNA , Resposta ao Choque Térmico/genéticaRESUMO
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.
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Neoplasias das Glândulas Salivares/diagnóstico por imagem , Neoplasias das Glândulas Salivares/patologia , Ultrassonografia de Intervenção/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia com Agulha de Grande Calibre/métodos , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Biópsia Guiada por Imagem/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Glândulas Salivares/diagnóstico por imagem , Glândulas Salivares/patologia , Sensibilidade e Especificidade , Adulto JovemRESUMO
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.
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Osso e Ossos/metabolismo , Suplementos Nutricionais , Magnésio/administração & dosagem , Fosfatos/metabolismo , Uremia/complicações , Calcificação Vascular/dietoterapia , Animais , Quelantes/administração & dosagem , Modelos Animais de Doenças , Células Endoteliais da Veia Umbilical Humana , Humanos , Magnésio/sangue , Masculino , Nefrectomia , Ratos , Ratos Wistar , Uremia/sangue , Uremia/dietoterapia , Calcificação Vascular/sangue , Calcificação Vascular/mortalidadeRESUMO
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.
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Dieta Hiperlipídica/efeitos adversos , Uremia/tratamento farmacológico , Calcificação Vascular/prevenção & controle , Vitamina E/uso terapêutico , Animais , Antioxidantes/uso terapêutico , Ratos , Ratos Wistar , Uremia/etiologia , Uremia/patologia , Calcificação Vascular/etiologia , Calcificação Vascular/patologiaRESUMO
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.
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Braquidactilia/diagnóstico , Braquidactilia/genética , Mutação , Proteína Relacionada ao Hormônio Paratireóideo/genética , Adulto , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/patologia , Criança , Feminino , Loci Gênicos , Humanos , Linhagem , Fenótipo , Sítios de Splice de RNA , Deleção de SequênciaRESUMO
This study describes fiber-type adaptations in hindlimb muscles, the interaction of sex, and the role of hypoxia on this response in 12-wk â 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.
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Membro Posterior/citologia , Membro Posterior/fisiologia , Fibras Musculares de Contração Rápida/fisiologia , Fibras Musculares de Contração Lenta/fisiologia , Nefrectomia , Animais , Peso Corporal/fisiologia , Capilares/citologia , Capilares/fisiologia , Ingestão de Alimentos/fisiologia , Feminino , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Hipóxia/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Testes de Função Renal , Masculino , Fibras Musculares de Contração Rápida/ultraestrutura , Fibras Musculares de Contração Lenta/ultraestrutura , Cadeias Pesadas de Miosina/metabolismo , Tamanho do Órgão/fisiologia , Ratos , Ratos Wistar , Caracteres Sexuais , Succinato Desidrogenase/metabolismo , Testosterona/metabolismo , Uremia/patologiaRESUMO
The increasing contamination of soil with heavy metals poses a problem to environmental sustainability. Among these pollutants, lead is particularly concerning due to its persistence in the environment, with harmful effects on human health and ecosystems. Various strategies that combine phytoremediation techniques with soil amendments have emerged to mitigate lead contamination. In this context, biochar has gained significant attention for its potential to enhance soil quality and remediate metal-contaminated environments. This study aims to investigate the combined effect of biochar amendments on the phytoremediation of lead-contaminated shooting range soils. A series of experiments were conducted to determine the impact of the amount and distribution of biochar on lead removal from soil. Soil samples were incubated with biochar for one week, after which two types of seeds (Brassica rapa and Lolium perenne) were planted. Plant and root lengths, as well as the number of germinated seeds, were measured, and a statistical analysis was conducted to determine the influence of the amendments. After one month, the Pb concentration decreased by more than 70%. Our results demonstrate that seed germination and plant growth were significantly better in soil samples where biochar was mixed rather than applied superficially, with the optimal performance observed at a 10% wt. biochar amendment. Additionally, the combined use of biochar and phytoremediation proved highly effective in immobilizing lead and reducing its bioavailability. These findings suggest that the combination of biochar, particularly when mixed at appropriate concentrations, and Brassica rapa significantly improved lead removal efficiency.
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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.
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Doenças do Cão , Neoplasias Mamárias Animais , Hormônio Paratireóideo , Vitamina D , Animais , Cães , Feminino , Doenças do Cão/sangue , Neoplasias Mamárias Animais/sangue , Vitamina D/sangue , Vitamina D/análogos & derivados , Estudos de Casos e Controles , Hormônio Paratireóideo/sangue , Cálcio/sangue , Fósforo/sangueRESUMO
Newborns who do not reach a weight appropriate for their gestational age and sex can be classified in different ways. This article defines the concepts of small for gestational age (SGA) and intrauterine growth restriction, as well as the underlying causes of these conditions, with the goal of establishing consensus definitions for these patients, in whom treatment with growth hormone throughout childhood may be indicated and who may be at risk of developing endocrine or metabolic disorders in puberty and adulthood. Most SGA children experience spontaneous catch-up growth that is usually completed by age 2 years. In SGA children who remain short, treatment with recombinant human growth hormone is effective, increasing adult height. Small for gestational age infants with rapid catch-up growth and marked weight gain are at increased risk of premature adrenarche, early puberty, polycystic ovary syndrome (girls), insulin resistance and obesity, all of which are risk factors for type 2 diabetes and metabolic syndrome in adulthood. The SGA status can affect different areas of neurodevelopment and manifest at different stages in life; neurodevelopmental outcomes are better in SGA infants with spontaneous catch-up growth. Due to the potential risks associated with SGA, adequate characterization of these patients at birth is imperative, as it allows initiation of appropriate follow-up and early detection of abnormalities.
Assuntos
Recém-Nascido Pequeno para a Idade Gestacional , Feminino , Humanos , Recém-Nascido , Masculino , Retardo do Crescimento Fetal/diagnóstico , Seguimentos , Fatores de RiscoRESUMO
Long non-coding RNAs (lncRNAs) are involved in numerous biological processes and serve crucial regulatory functions in both animals and plants. Nevertheless, there is limited understanding of lncRNAs and their patterns of expression and roles in sharks. In the current study, we systematically identified and characterized lncRNAs in the blue shark (Prionace glauca) from four tissues (liver, spleen, muscle, and kidney) using high-throughput sequencing and bioinformatics tools. A total of 21,932 high-confidence lncRNAs were identified, with 8984 and 3067 stably and tissue-specific expressed lncRNAs, respectively. In addition, a total of 45,007 differentially expressed (DE) lncRNAs were obtained among tissues, with kidney versus muscle having the largest numbers across tissues. DE lncRNAs trans target protein-coding genes were predicted, and functional gene ontology enrichment of these genes showed GO terms such as muscle system processes, cellular/metabolic processes, and stress and immune responses, all of which correspond with the specific biological functions of each tissue analyzed. These results advance our knowledge of lncRNAs in sharks and present novel data on tissue-specific lncRNAs, providing key information to support future functional shark investigations.