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1.
Nature ; 619(7969): 363-370, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37407814

RESUMO

In mammalian cells, the decision to proliferate is thought to be irreversibly made at the restriction point of the cell cycle1,2, when mitogen signalling engages a positive feedback loop between cyclin A2/cyclin-dependent kinase 2 (CDK2) and the retinoblastoma protein3-5. Contrary to this textbook model, here we show that the decision to proliferate is actually fully reversible. Instead, we find that all cycling cells will exit the cell cycle in the absence of mitogens unless they make it to mitosis and divide first. This temporal competition between two fates, mitosis and cell cycle exit, arises because cyclin A2/CDK2 activity depends upon CDK4/6 activity throughout the cell cycle, not just in G1 phase. Without mitogens, mitosis is only observed when the half-life of cyclin A2 protein is long enough to sustain CDK2 activity throughout G2/M. Thus, cells are dependent on mitogens and CDK4/6 activity to maintain CDK2 activity and retinoblastoma protein phosphorylation throughout interphase. Consequently, even a 2-h delay in a cell's progression towards mitosis can induce cell cycle exit if mitogen signalling is lost. Our results uncover the molecular mechanism underlying the restriction point phenomenon, reveal an unexpected role for CDK4/6 activity in S and G2 phases and explain the behaviour of all cells following loss of mitogen signalling.


Assuntos
Ciclo Celular , Quinase 4 Dependente de Ciclina , Quinase 6 Dependente de Ciclina , Fase G2 , Fase S , Animais , Ciclina A2/metabolismo , Quinase 2 Dependente de Ciclina/metabolismo , Quinase 4 Dependente de Ciclina/deficiência , Quinase 4 Dependente de Ciclina/metabolismo , Mitógenos/deficiência , Mitógenos/metabolismo , Mitose , Fosforilação , Proteína do Retinoblastoma/química , Proteína do Retinoblastoma/metabolismo , Quinase 6 Dependente de Ciclina/deficiência , Quinase 6 Dependente de Ciclina/metabolismo , Fase G1
2.
PLoS Genet ; 20(5): e1011236, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38722825

RESUMO

Patients with ER-negative breast cancer have the worst prognosis of all breast cancer subtypes, often experiencing rapid recurrence or progression to metastatic disease shortly after diagnosis. Given that metastasis is the primary cause of mortality in most solid tumors, understanding metastatic biology is crucial for effective intervention. Using a mouse systems genetics approach, we previously identified 12 genes associated with metastatic susceptibility. Here, we extend those studies to identify Resf1, a poorly characterized gene, as a novel metastasis susceptibility gene in ER- breast cancer. Resf1 is a large, unstructured protein with an evolutionarily conserved intron-exon structure, but with poor amino acid conservation. CRISPR or gene trap mouse models crossed to the Polyoma Middle-T antigen genetically engineered mouse model (MMTV-PyMT) demonstrated that reduction of Resf1 resulted in a significant increase in tumor growth, a shortened overall survival time, and increased incidence and number of lung metastases, consistent with patient data. Furthermore, an analysis of matched tail and primary tissues revealed loss of the wildtype copy in tumor tissue, consistent with Resf1 being a tumor suppressor. Mechanistic analysis revealed a potential role of Resf1 in transcriptional control through association with compound G4 quadruplexes in expressed sequences, particularly those associated with ribosomal biogenesis. These results suggest that loss of Resf1 enhances tumor progression in ER- breast cancer through multiple alterations in both transcriptional and translational control.


Assuntos
Proteínas Repressoras , Neoplasias de Mama Triplo Negativas , Animais , Feminino , Humanos , Camundongos , Linhagem Celular Tumoral , Quadruplex G , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/patologia , Metástase Neoplásica , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
4.
Small ; : e2400679, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488771

RESUMO

Chalcogel represents a unique class of meso- to macroporous nanomaterials that offer applications in energy and environmental pursuits. Here, the synthesis of an ion-exchangeable amorphous chalcogel using a nominal composition of K2 CoMo2 S10 (KCMS) at room temperature is reported. Synchrotron X-ray pair distribution function (PDF), X-ray absorption near-edge structure (XANES), and extended X-ray absorption fine structure (EXAFS) reveal a plausible local structure of KCMS gel consisting of Mo5+ 2 and Mo4+ 3 clusters in the vicinity of di/polysulfides which are covalently linked by Co2+ ions. The ionically bound K+ ions remain in the percolating pores of the Co-Mo-S covalent network. XANES of Co K-edge shows multiple electronic transitions, including quadrupole (1s→3d), shakedown (1s→4p + MLCT), and dipole allowed 1s→4p transitions. Remarkably, despite a lack of regular channels as in some crystalline solids, the amorphous KCMS gel shows ion-exchange properties with UO2 2+ ions. Additionally, it also presents surface sorption via [S∙∙∙∙UO2 2+ ] covalent interactions. Overall, this study underscores the synthesis of quaternary chalcogels incorporating alkali metals and their potential to advance separation science for cations and oxo-cationic species by integrating a synergy of surface sorption and ion-exchange.

5.
J Tissue Viability ; 33(2): 318-323, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38360494

RESUMO

AIM: The aim of the study was to describe types and frequencies of skin care interventions and products provided in institutional long-term care. MATERIALS AND METHODS: Baseline data from a cluster randomized controlled trial conducted in nursing homes in Berlin, Germany was collected before randomization. Numbers, proportions and frequencies of washing, showering and bathing, and the application of leave-on products were calculated. Product labels were iteratively and inductively categorized into overarching terms and concepts. RESULTS: A total of n = 314 residents participated in the study. In the majority, washing of the whole body was done once daily, and showering was performed once per week or more rarely. The majority received leave-on products daily on the face and once per week on the whole body. Most of the skin care interventions were delivered by nurses. There was marked heterogeneity in terms of product names, whereas the product names reveal little about the ingredients or composition. CONCLUSION: Personal hygiene and cleansing interventions are major parts of clinical practice in long-term care. Daily washing is a standard practice at the moment. In contrast, leave-on products are used infrequently. To what extent the provided care promotes skin integrity is unclear. Due to the heterogeneity and partly misleading labels of skin care products, informed decision making is difficult to implement at present. GOV IDENTIFIER: NCT03824886.


Assuntos
Assistência de Longa Duração , Higiene da Pele , Humanos , Estudos Transversais , Higiene da Pele/métodos , Higiene da Pele/normas , Higiene da Pele/estatística & dados numéricos , Feminino , Assistência de Longa Duração/métodos , Assistência de Longa Duração/normas , Assistência de Longa Duração/estatística & dados numéricos , Masculino , Alemanha , Idoso de 80 Anos ou mais , Idoso , Casas de Saúde/estatística & dados numéricos , Casas de Saúde/normas , Casas de Saúde/organização & administração
6.
BMC Pediatr ; 23(1): 155, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-37009866

RESUMO

BACKGROUND: Universal screening for neonatal hyperbilirubinemia risk assessment is recommended by the American Academy of Pediatrics to reduce related morbidity. In Bangladesh and in many low- and middle-income countries, there is no screening for neonatal hyperbilirubinemia. Furthermore, neonatal hyperbilirubinemia may not be recognized as a medically significant condition by caregivers and community members. We aimed to evaluate the acceptability and operational feasibility of community health worker (CHW)-led, home-based, non-invasive neonatal hyperbilirubinemia screening using a transcutaneous bilimeter in Shakhipur, a rural subdistrict in Bangladesh. METHODS: We employed a two-step process. In the formative phase, we conducted eight focus group discussions with parents and grandparents of infants and eight key informant interviews with public and private healthcare providers and managers to explore their current knowledge, perceptions, practices, and challenges regarding identification and management of neonatal hyperbilirubinemia. Next, we piloted a prenatal sensitization intervention and home-based screening by CHWs using transcutaneous bilimeters and evaluated the acceptability and operational feasibility of this approach through focus group discussions and key informant interviews with parents, grandparents and CHWs. RESULTS: Formative findings identified misconceptions regarding neonatal hyperbilirubinemia causes and health risks among caregivers in rural Bangladesh. CHWs were comfortable with adoption, maintenance and use of the device in routine home visits. Transcutaneous bilimeter-based screening was also widely accepted by caregivers and family members due to its noninvasive technique and immediate display of findings at home. Prenatal sensitization of caregivers and family members helped to create a supportive environment in the family and empowered mothers as primary caregivers. CONCLUSION: Adopting household neonatal hyperbilirubinemia screening in the postnatal period by CHWs using a transcutaneous bilimeter is an acceptable approach by both CHWs and families and may increase rates of screening to prevent morbidity and mortality.


Assuntos
Agentes Comunitários de Saúde , Hiperbilirrubinemia Neonatal , Lactente , Recém-Nascido , Feminino , Gravidez , Humanos , Criança , Bangladesh , Estudos de Viabilidade , Hiperbilirrubinemia Neonatal/diagnóstico , Triagem Neonatal/métodos , Mães
7.
Skin Pharmacol Physiol ; 36(2): 51-66, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36750047

RESUMO

BACKGROUND: Skin care is a basic, daily activity performed by formal and informal caregivers from birth until end of life. Skin care activities are influenced by different factors, e.g., culture, knowledge, industrial developments and marketing activities. Therefore, various preferences, traditions, and behaviors exist worldwide including skin care of neonates and infants. The objective of this scoping review was to obtain an overview about the evidence of skin care activities in neonates and infants. Studies from 2010 were eligible if the population was (skin) healthy neonates and infants; if the concept was skin care interventions; and if the context was at home, in a community setting, in a pediatric outpatient service, or in a hospital. We searched for the literature via OVID in MEDLINE and Embase, in the Cochrane Library, in trial registries and for gray literature. SUMMARY: We identified 42 studies since 2010, which examined four main skin care interventions: bathing, wiping, washing, and topical application of leave-on products. Details of interventions were often not reported, and if they were, they were not comparable. The four skin care interventions focused on 13 different care goals, mainly prevention of skin diseases, maintaining skin barrier function, and improving (skin) health. We evaluated effects of skin care interventions using 57 different outcome domains; 39 of 57 were skin-related and 18 were not. Mostly, laboratory or instrumental measurements were used. KEY MESSAGES: Our scoping review identified four skin care interventions with a broad heterogeneity of product categories and application details. Studies in skin care interventions should include all relevant information about product category and application details to ensure comparability of study results. This would be helpful in developing recommendations for formal and informal caregivers. We identified 13 skin care goals. "Maintaining healthy skin/skin barrier function/skin barrier integrity," "prevention of atopic dermatitis," "cleansing," and "improving skin barrier function" were most often allocated to skin care interventions. There is substantial variability regarding outcome domains in skin care research. Our results support the need of developing core outcome sets in the field of skin care in healthy skin, especially in this age-group of neonates and infants.


Assuntos
Higiene da Pele , Pele , Recém-Nascido , Humanos , Lactente , Criança , Higiene da Pele/métodos
8.
Geriatr Nurs ; 54: 331-340, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37950968

RESUMO

OBJECTIVES: To identify possible factors associated with different severities of xerosis cutis and to describe possible associations between (skin) care dependency and application of moisturizers. DESIGN: Cross-sectional study using baseline data from a cluster-randomized controlled trial. Demographic and health characteristics, skin physiological measurements, functional abilities and application of moisturizers were compared between the participants with mild and severe dry skin. Frequency of moisturization were also compared based on the participants' skin care dependency. RESULTS: The more distal the body area, the more severe xerosis were observed. There were no or minor differences between the groups, except for the stratum corneum hydration and skin surface pH. Participants with severe xerosis received moisturizers less often. Skin care dependent residents received moisturizers frequently. CONCLUSION: There is under-application regarding xerosis cutis treatment in long-term care. Skin care provided by nurses, in adequate frequencies, might be helpful compared to skin care performed by the residents themselves.


Assuntos
Assistência de Longa Duração , Higiene da Pele , Idoso , Humanos , Atividades Cotidianas , Estudos Transversais , Prevalência , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
Bioinformatics ; 36(19): 4869-4875, 2020 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-32614400

RESUMO

MOTIVATION: Promoter is a short region of DNA which is responsible for initiating transcription of specific genes. Development of computational tools for automatic identification of promoters is in high demand. According to the difference of functions, promoters can be of different types. Promoters may have both intra- and interclass variation and similarity in terms of consensus sequences. Accurate classification of various types of sigma promoters still remains a challenge. RESULTS: We present iPromoter-BnCNN for identification and accurate classification of six types of promoters-σ24,σ28,σ32,σ38,σ54,σ70. It is a CNN-based classifier which combines local features related to monomer nucleotide sequence, trimer nucleotide sequence, dimer structural properties and trimer structural properties through the use of parallel branching. We conducted experiments on a benchmark dataset and compared with six state-of-the-art tools to show our supremacy on 5-fold cross-validation. Moreover, we tested our classifier on an independent test dataset. AVAILABILITY AND IMPLEMENTATION: Our proposed tool iPromoter-BnCNN web server is freely available at http://103.109.52.8/iPromoter-BnCNN. The runnable source code can be found https://colab.research.google.com/drive/1yWWh7BXhsm8U4PODgPqlQRy23QGjF2DZ. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Fator sigma , Software , DNA , Regiões Promotoras Genéticas , Análise de Sequência de DNA
10.
FASEB J ; 34(9): 12805-12819, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32772419

RESUMO

Increased endothelial permeability leads to excessive exudation of plasma proteins and leukocytes in the interstitium, which characterizes several vascular diseases including acute lung injury. The myosin light chain kinase long (MYLK-L) isoform is canonically known to regulate the endothelial permeability by phosphorylating myosin light chain (MLC-P). Compared to the short MYLK isoform, MYLK-L contains an additional stretch of ~919 amino acid at the N-terminus of unknown function. We show that thapsigargin and thrombin-induced SOCE was markedly reduced in Mylk-L-/- endothelial cells (EC) or MYLK-L-depleted human EC. These agonists also failed to increase endothelial permeability in MYLK-L-depleted EC and Mylk-L-/- lungs, thus demonstrating the novel role of MYLK-L-induced SOCE in increasing vascular permeability. MYLK-L augmented SOCE by increasing endoplasmic reticulum (ER)-plasma membrane (PM) junctions and STIM1 translocation to these junctions. Transduction of N-MYLK domain (amino acids 1-919 devoid of catalytic activity) into Mylk-L-/- EC rescued SOCE to the level seen in control EC in a STIM1-dependent manner. N-MYLK-induced SOCE augmented endothelial permeability without MLC-P via an actin-binding motif, DVRGLL. Liposomal-mediated delivery of N-MYLK mutant but not ∆DVRGLL-N-MYLK mutant in Mylk-L-/- mice rescued vascular permeability increase in response to endotoxin, indicating that targeting of DVRGLL motif within MYLK-L may limit SOCE-induced vascular hyperpermeability.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Permeabilidade Capilar , Membrana Celular/enzimologia , Retículo Endoplasmático/enzimologia , Quinase de Cadeia Leve de Miosina/metabolismo , Lesão Pulmonar Aguda/metabolismo , Animais , Células Endoteliais da Veia Umbilical Humana , Humanos , Isoenzimas/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas de Neoplasias/metabolismo , Molécula 1 de Interação Estromal/metabolismo
11.
Am J Physiol Gastrointest Liver Physiol ; 316(1): G1-G14, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30307745

RESUMO

Most kidney stones (KS) are composed of calcium oxalate and small increases in urine oxalate enhance the stone risk. Obesity is a risk factor for KS, and urinary oxalate excretion increases with increased body size. We previously established the obese ob/ob ( ob) mice as a model (3.3-fold higher urine oxalate) to define the pathogenesis of obesity-associated hyperoxaluria (OAH). The purpose of this study was to test the hypothesis that the obesity-associated enhanced small intestinal paracellular permeability contributes to OAH by increasing passive paracellular intestinal oxalate absorption. ob Mice have significantly higher jejunal (1.6-fold) and ileal (1.4-fold) paracellular oxalate absorption ex vivo and significantly higher (5-fold) urine [13C]oxalate following oral gavage with [13C]oxalate, indicating increased intestinal oxalate absorption in vivo. The observation of higher oxalate absorption in vivo compared with ex vivo suggests the possibility of increased paracellular permeability along the entire gut. Indeed, ob mice have significantly higher fractions of the administered sucrose (1.7-fold), lactulose (4.4-fold), and sucralose (3.1-fold) excreted in the urine, reflecting increased gastric, small intestinal, and colonic paracellular permeability, respectively. The ob mice have significantly reduced gastrointestinal occludin, zonula occludens-1, and claudins-1 and -3 mRNA and total protein expression. Proinflammatory cytokines and oxidative stress, which are elevated in obesity, significantly enhanced paracellular intestinal oxalate absorption in vitro and ex vivo. We conclude that obese mice have significantly higher intestinal oxalate absorption and enhanced gastrointestinal paracellular permeability in vivo, which would likely contribute to the pathogenesis of OAH, since there is a transepithelial oxalate concentration gradient to drive paracellular intestinal oxalate absorption. NEW & NOTEWORTHY This study shows that the obese ob/ob mice have significantly increased gastrointestinal paracellular oxalate absorption and remarkably enhanced paracellular permeability along the entire gut in vivo, which are likely mediated by the obesity-associated increased systemic and intestinal inflammation and oxidative stress. A transepithelial oxalate concentration gradient driving gastrointestinal paracellular oxalate absorption exists, and therefore, our novel findings likely contribute to the hyperoxaluria observed in the ob/ob mice and hence to the pathogenesis of obesity-associated hyperoxaluria.


Assuntos
Trato Gastrointestinal/metabolismo , Hiperoxalúria/fisiopatologia , Mucosa Intestinal/metabolismo , Obesidade/metabolismo , Animais , Inflamação/metabolismo , Absorção Intestinal/fisiologia , Intestino Delgado/metabolismo , Jejuno/metabolismo , Camundongos Endogâmicos C57BL , Permeabilidade
12.
Arterioscler Thromb Vasc Biol ; 38(9): 2028-2040, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29976771

RESUMO

Objective- We investigated the hypothesis that HDL (high-density lipoprotein) dysfunction in Scarb1-/- mice negatively affects cardiac function both in the absence and in the presence of pressure overload. Second, we evaluated whether normalization of HDL metabolism in Scarb1-/- mice by hepatocyte-specific SR-BI (scavenger receptor class B, type I) expression after E1E3E4-deleted adenoviral AdSR-BI (E1E3E4-deleted adenoviral vector expressing SR-BI protein in hepatocytes) transfer abrogates the effects of total body SR-BI deficiency on cardiac structure and function. Approach and Results- Transverse aortic constriction (TAC) or sham operation was performed at the age of 14 weeks, 2 weeks after saline injection or after gene transfer with AdSR-BI or with the control vector Adnull. Mortality rate in Scarb1-/- TAC mice was significantly increased compared with wild-type TAC mice during 8 weeks of follow-up (hazard ratio, 2.02; 95% CI, 1.14-3.61). Hepatocyte-specific SR-BI gene transfer performed 2 weeks before induction of pressure overload by TAC potently reduced mortality in Scarb1-/- mice (hazard ratio, 0.329; 95% CI, 0.180-0.600). Hepatocyte-specific SR-BI expression abrogated increased cardiac hypertrophy and lung congestion and counteracted increased myocardial apoptosis and interstitial and perivascular fibrosis in Scarb1-/- TAC mice. Scarb1-/- sham mice were, notwithstanding the absence of detectable structural heart disease, characterized by systolic and diastolic dysfunction and hypotension, which were completely counteracted by AdSR-BI transfer. Furthermore, AdSR-BI transfer abrogated increased end-diastolic pressure and diastolic dysfunction in Scarb1-/- TAC mice. Increased oxidative stress and reduced antioxidant defense systems in Scarb1-/- mice were rescued by AdSR-BI transfer. Conclusions- The detrimental effects of SR-BI deficiency on cardiac structure and function are nullified by hepatocyte-specific SR-BI transfer, which restores HDL metabolism.


Assuntos
Cardiomegalia/terapia , Técnicas de Transferência de Genes , Hepatócitos/metabolismo , Receptores Depuradores Classe B/genética , Animais , Apoptose , Pressão Sanguínea , Cardiomegalia/sangue , Cardiomegalia/genética , Cardiomegalia/fisiopatologia , Células Cultivadas , HDL-Colesterol/sangue , Feminino , Fibrose , Expressão Gênica , Camundongos Knockout , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Estresse Oxidativo
13.
Am J Physiol Cell Physiol ; 315(5): C687-C698, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30020825

RESUMO

Most kidney stones (KS) are composed of calcium oxalate, and small increases in urine oxalate affect the stone risk. Intestinal oxalate secretion mediated by anion exchanger SLC26A6 (PAT1) plays a crucial role in limiting net absorption of ingested oxalate, thereby preventing hyperoxaluria and related KS, reflecting the importance of understanding regulation of intestinal oxalate transport. We previously showed that ATP and UTP inhibit oxalate transport by human intestinal Caco2-BBE cells (C2). Since ATP is rapidly degraded to adenosine (ADO), we examined whether intestinal oxalate transport is regulated by ADO. We measured [14C]oxalate uptake in the presence of an outward Cl gradient as an assay of Cl-oxalate exchange activity, ≥49% of which is PAT1-mediated in C2 cells. We found that ADO significantly inhibited oxalate transport by C2 cells, an effect completely blocked by the nonselective ADO receptor antagonist 8- p-sulfophenyltheophylline. ADO also significantly inhibited oxalate efflux by C2 cells, which is important since PAT1 mediates oxalate efflux in vivo. Using pharmacological antagonists and A2B adenosine receptor (A2B AR) siRNA knockdown studies, we observed that ADO inhibits oxalate transport through the A2B AR, phospholipase C, and PKC. ADO inhibits oxalate transport by reducing PAT1 surface expression as shown by biotinylation studies. We conclude that ADO inhibits oxalate transport by lowering PAT1 surface expression in C2 cells through signaling pathways including the A2B AR, PKC, and phospholipase C. Given higher ADO levels and overexpression of the A2B AR in inflammatory bowel disease (IBD), our findings have potential relevance to pathophysiology of IBD-associated hyperoxaluria and related KS.


Assuntos
Adenosina/metabolismo , Sistemas de Transporte de Aminoácidos/genética , Doenças Inflamatórias Intestinais/genética , Receptor A2B de Adenosina/genética , Simportadores/genética , Adenosina/administração & dosagem , Antagonistas do Receptor A2 de Adenosina/administração & dosagem , Trifosfato de Adenosina/metabolismo , Transporte Biológico/genética , Células CACO-2 , Humanos , Hiperoxalúria/genética , Hiperoxalúria/metabolismo , Hiperoxalúria/patologia , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Cálculos Renais/genética , Cálculos Renais/metabolismo , Cálculos Renais/patologia , Oxalatos/metabolismo , Receptor A2B de Adenosina/metabolismo , Fatores de Risco , Transdução de Sinais/efeitos dos fármacos , Teofilina/administração & dosagem , Fosfolipases Tipo C/genética
14.
Kidney Int ; 93(5): 1098-1107, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29395336

RESUMO

Most kidney stones are composed of calcium oxalate, and minor changes in urine oxalate affect the stone risk. Obesity is a risk factor for kidney stones and a positive correlation of unknown etiology between increased body size, and elevated urinary oxalate excretion has been reported. Here, we used obese ob/ob (ob) mice to elucidate the pathogenesis of obesity-associated hyperoxaluria. These ob mice have significant hyperoxaluria (3.3-fold) compared with control mice, which is not due to overeating as shown by pair-feeding studies. Dietary oxalate removal greatly ameliorated this hyperoxaluria, confirming that it is largely enteric in origin. Transporter SLC26A6 (A6) plays an essential role in active transcellular intestinal oxalate secretion, and ob mice have significantly reduced jejunal A6 mRNA (- 80%) and total protein (- 62%) expression. While net oxalate secretion was observed in control jejunal tissues mounted in Ussing chambers, net absorption was seen in ob tissues, due to significantly reduced secretion. We hypothesized that the obesity-associated increase in intestinal and systemic inflammation, as reflected by elevated proinflammatory cytokines, suppresses A6-mediated intestinal oxalate secretion and contributes to obesity-associated hyperoxaluria. Indeed, proinflammatory cytokines (elevated in ob mice) significantly decreased intestinal oxalate transport in vitro by reducing A6 mRNA and total protein expression. Proinflammatory cytokines also significantly reduced active mouse jejunal oxalate secretion, converting oxalate transport from net secretion in vehicle-treated tissues to net absorption in proinflammatory cytokines-treated tissues. Thus, reduced active intestinal oxalate secretion, likely secondary to local and systemic inflammation, contributes to the pathogenesis of obesity-associated hyperoxaluria. Hence, proinflammatory cytokines represent potential therapeutic targets.


Assuntos
Hiperoxalúria/etiologia , Secreções Intestinais/metabolismo , Jejuno/metabolismo , Obesidade/complicações , Oxalatos/metabolismo , Animais , Antiporters/metabolismo , Células CACO-2 , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Humanos , Hiperoxalúria/metabolismo , Hiperoxalúria/fisiopatologia , Mediadores da Inflamação/metabolismo , Absorção Intestinal , Jejuno/fisiopatologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , Obesidade/fisiopatologia , Via Secretória , Transportadores de Sulfato/metabolismo
15.
Mol Ther ; 25(11): 2513-2525, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28822689

RESUMO

A causal role of hypercholesterolemia in non-ischemic heart failure has never been demonstrated. Adeno-associated viral serotype 8 (AAV8)-low-density lipoprotein receptor (AAV8-LDLr) gene transfer was performed in LDLr-deficient mice without and with pressure overload induced by transverse aortic constriction (TAC). AAV8-LDLr gene therapy resulted in an 82.8% (p < 0.0001) reduction of plasma cholesterol compared with controls. Mortality rate was lower (p < 0.05) in AAV8-LDLr TAC mice compared with control TAC mice (hazard ratio for mortality 0.457, 95% confidence interval [CI] 0.237-0.882) during 8 weeks of follow-up. AAV8-LDLr gene therapy attenuated cardiac hypertrophy, reduced interstitial and perivascular fibrosis, and decreased lung congestion in TAC mice. Cardiac function, quantified by invasive hemodynamic measurements and magnetic resonance imaging, was significantly improved 8 weeks after sham operation or after TAC in AAV8-LDLr mice compared with respective control groups. Myocardial protein levels of mammalian target of rapamycin and of acetyl-coenzyme A carboxylase were strikingly decreased following cholesterol lowering in mice without and with pressure overload. AAV8-LDLr therapy potently reduced cardiac glucose uptake and counteracted metabolic remodeling following pressure overload. Furthermore, oxidative stress and myocardial apoptosis were decreased following AAV8-LDLr therapy in mice with pressure overload. In conclusion, cholesterol-lowering gene therapy potently counteracts structural and metabolic remodeling, and enhances cardiac function.


Assuntos
Cardiomegalia/terapia , Cardiomiopatias/terapia , Colesterol/metabolismo , Terapia Genética/métodos , Vetores Genéticos/metabolismo , Receptores de LDL/genética , Acetil-CoA C-Acetiltransferase/genética , Acetil-CoA C-Acetiltransferase/metabolismo , Animais , Aorta/cirurgia , Biomarcadores/metabolismo , Cardiomegalia/etiologia , Cardiomegalia/metabolismo , Cardiomegalia/mortalidade , Cardiomiopatias/etiologia , Cardiomiopatias/metabolismo , Cardiomiopatias/mortalidade , Constrição Patológica/complicações , Constrição Patológica/metabolismo , Constrição Patológica/patologia , Dependovirus/genética , Dependovirus/metabolismo , Feminino , Expressão Gênica , Vetores Genéticos/administração & dosagem , Vetores Genéticos/química , Testes de Função Cardíaca , Hemodinâmica , Camundongos , Camundongos Knockout , Miocárdio/metabolismo , Miocárdio/patologia , Receptores de LDL/deficiência , Análise de Sobrevida , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
16.
Sensors (Basel) ; 17(10)2017 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-29019962

RESUMO

The Pacific Islands Fisheries Science Center deploys the Modular Optical Underwater Survey System (MOUSS) to estimate the species-specific, size-structured abundance of commercially-important fish species in Hawaii and the Pacific Islands. The MOUSS is an autonomous stereo-video camera system designed for the in situ visual sampling of fish assemblages. This system is rated to 500 m and its low-light, stereo-video cameras enable identification, counting, and sizing of individuals at a range of 0.5-10 m. The modular nature of MOUSS allows for the efficient and cost-effective use of various imaging sensors, power systems, and deployment platforms. The MOUSS is in use for surveys in Hawaii, the Gulf of Mexico, and Southern California. In Hawaiian waters, the system can effectively identify individuals to a depth of 250 m using only ambient light. In this paper, we describe the MOUSS's application in fisheries research, including the design, calibration, analysis techniques, and deployment mechanism.

17.
Int J Mol Sci ; 18(9)2017 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-28930153

RESUMO

Epidemiological studies support an independent inverse association between high-density lipoprotein (HDL) cholesterol levels and heart failure incidence. The effect of selective HDL-raising adeno-associated viral serotype 8-human apolipoprotein (apo) A-I (AAV8-A-I) gene transfer on cardiac remodeling induced by transverse aortic constriction (TAC) was evaluated in C57BL/6 low-density lipoprotein receptor-deficient mice. Septal wall thickness and cardiomyocyte cross-sectional area were reduced by 16.5% (p < 0.001) and by 13.8% (p < 0.01), respectively, eight weeks after TAC in AAV8-A-I mice (n = 24) compared to control mice (n = 39). Myocardial capillary density was 1.11-fold (p < 0.05) higher and interstitial cardiac fibrosis was 45.3% (p < 0.001) lower in AAV8-A-I TAC mice than in control TAC mice. Lung weight and atrial weight were significantly increased in control TAC mice compared to control sham mice, but were not increased in AAV8-A-I TAC mice. The peak rate of isovolumetric contraction was 1.19-fold (p < 0.01) higher in AAV8-A-I TAC mice (n = 17) than in control TAC mice (n = 29). Diastolic function was also significantly enhanced in AAV8-A-I TAC mice compared to control TAC mice. Nitro-oxidative stress and apoptosis were significantly reduced in the myocardium of AAV8-A-I TAC mice compared to control TAC mice. In conclusion, selective HDL-raising human apo A-I gene transfer potently counteracts the development of pressure overload-induced cardiomyopathy.


Assuntos
Apolipoproteína A-I/metabolismo , Cardiomegalia/terapia , Cardiomiopatias/terapia , Terapia Genética/métodos , Lipoproteínas HDL/metabolismo , Animais , Apolipoproteína A-I/genética , Cardiomegalia/genética , Cardiomegalia/metabolismo , Cardiomiopatias/genética , Cardiomiopatias/metabolismo , Fibrose/genética , Fibrose/terapia , Coração/fisiopatologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miocárdio/metabolismo , Miocárdio/patologia
18.
Int J Mol Sci ; 18(7)2017 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-28718833

RESUMO

Studies evaluating the effects of high-saturated fat diets on cardiac function are most often confounded by diet-induced obesity and by systemic insulin resistance. We evaluated whether coconut oil, containing C12:0 and C14:0 as main fatty acids, aggravates pressure overload-induced cardiomyopathy induced by transverse aortic constriction (TAC) in C57BL/6 mice. Mortality rate after TAC was higher (p < 0.05) in 0.2% cholesterol 10% coconut oil diet-fed mice than in standard chow-fed mice (hazard ratio 2.32, 95% confidence interval 1.16 to 4.64) during eight weeks of follow-up. The effects of coconut oil on cardiac remodeling occurred in the absence of weight gain and of systemic insulin resistance. Wet lung weight was 1.76-fold (p < 0.01) higher in coconut oil mice than in standard chow mice. Myocardial capillary density (p < 0.001) was decreased, interstitial fibrosis was 1.88-fold (p < 0.001) higher, and systolic and diastolic function was worse in coconut oil mice than in standard chow mice. Myocardial glucose uptake was 1.86-fold (p < 0.001) higher in coconut oil mice and was accompanied by higher myocardial pyruvate dehydrogenase levels and higher acetyl-CoA carboxylase levels. The coconut oil diet increased oxidative stress. Myocardial triglycerides and free fatty acids were lower (p < 0.05) in coconut oil mice. In conclusion, coconut oil aggravates pressure overload-induced cardiomyopathy.


Assuntos
Cardiomiopatias/patologia , Óleo de Coco/efeitos adversos , Resistência à Insulina , Miocárdio/patologia , Obesidade/patologia , Pressão , Animais , Aorta/patologia , Peso Corporal , Capilares/patologia , Cardiomiopatias/sangue , Cardiomiopatias/complicações , Cardiomiopatias/fisiopatologia , Colesterol , Constrição Patológica , Diástole , Dieta , Feminino , Fibrose , Glucose/metabolismo , Hemodinâmica , Hipertrofia Ventricular Direita/complicações , Hipertrofia Ventricular Direita/patologia , Hipertrofia Ventricular Direita/fisiopatologia , Estimativa de Kaplan-Meier , Pulmão/patologia , Camundongos Endogâmicos C57BL , Estresse Oxidativo , Transdução de Sinais , Sístole , Fator de Crescimento Transformador beta1/metabolismo
19.
J Med Syst ; 41(4): 50, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28213882

RESUMO

Telecare Medical Information System (TMIS) supports a standard platform to the patient for getting necessary medical treatment from the doctor(s) via Internet communication. Security protection is important for medical records (data) of the patients because of very sensitive information. Besides, patient anonymity is another most important property, which must be protected. Most recently, Chiou et al. suggested an authentication protocol for TMIS by utilizing the concept of cloud environment. They claimed that their protocol is patient anonymous and well security protected. We reviewed their protocol and found that it is completely insecure against patient anonymity. Further, the same protocol is not protected against mobile device stolen attack. In order to improve security level and complexity, we design a light weight authentication protocol for the same environment. Our security analysis ensures resilience of all possible security attacks. The performance of our protocol is relatively standard in comparison with the related previous research.


Assuntos
Computação em Nuvem , Segurança Computacional/instrumentação , Confidencialidade , Troca de Informação em Saúde/normas , Telemedicina/instrumentação , Algoritmos , Humanos , Internet
20.
Tumour Biol ; 37(3): 3097-103, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26427659

RESUMO

Esophageal squamous cell carcinoma (ESCC) is the second and third most common malignancy in Iranian males and females, respectively. Treatment of ESCC is largely ineffective due to lack of detection at early stages of the disease. In recent years, miRNA, a small RNA molecule, has drawn much attention to researchers as a potential biomarker for esophageal cancer. miR-93 and miR-143 are two miRNA molecules reported to be frequently deregulated in various cancers, including prostate, stomach, cervix, and etc. The purpose of this study was to investigate the expression levels of these miRNAs and evaluate their diagnostic and therapeutic potential in esophageal squamous cell carcinoma. In this study, total RNA was extracted from 30 tumor tissues and 30 nontumor tissues of esophageal tumor margins, using RNX-plus solution. After validating the quality and quantity of total RNA, cDNAs of interest were synthesized using microRNA-specific cDNA Synthesis Kit. The expression level of miR-93 and miR-143 was evaluated using quantitative real-time PCR with miRNA-specific primers. Finally, the obtained data was analyzed by SPSS ver.20 software and paired t test was performed to observe the significance of difference between groups. The expression level of miR-93 was significantly increased and of miR-143 was significantly decreased in most of the examined tumor tissues, compared to nontumor tissues. Also, our findings did not detect correlation between mir-93 and mir-143 expressions in regard to stage and grade of the samples. These findings suggest that the deregulation of these miRNAs may play an important role in esophageal squamous cell carcinoma. Both miR-93 and miR-143 might be used as potential biomarkers in esophageal squamous cell carcinoma. However, more studies with large population of samples are necessary.


Assuntos
Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/genética , MicroRNAs/fisiologia , Idoso , Carcinoma de Células Escamosas/etiologia , Neoplasias Esofágicas/etiologia , Carcinoma de Células Escamosas do Esôfago , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade
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