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1.
Nat Immunol ; 25(2): 282-293, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38172257

RESUMO

Preserving cells in a functional, non-senescent state is a major goal for extending human healthspans. Model organisms reveal that longevity and senescence are genetically controlled, but how genes control longevity in different mammalian tissues is unknown. Here, we report a new human genetic disease that causes cell senescence, liver and immune dysfunction, and early mortality that results from deficiency of GIMAP5, an evolutionarily conserved GTPase selectively expressed in lymphocytes and endothelial cells. We show that GIMAP5 restricts the pathological accumulation of long-chain ceramides (CERs), thereby regulating longevity. GIMAP5 controls CER abundance by interacting with protein kinase CK2 (CK2), attenuating its ability to activate CER synthases. Inhibition of CK2 and CER synthase rescues GIMAP5-deficient T cells by preventing CER overaccumulation and cell deterioration. Thus, GIMAP5 controls longevity assurance pathways crucial for immune function and healthspan in mammals.


Assuntos
Ceramidas , Proteínas de Ligação ao GTP , Animais , Humanos , Longevidade/genética , Células Endoteliais/metabolismo , Mamíferos/metabolismo
3.
BMC Pulm Med ; 23(1): 496, 2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38071285

RESUMO

BACKGROUND: Some patients with asthma demonstrate normal spirometry and remain undiagnosed without further testing. OBJECTIVE: To determine clinical predictors of asthma in symptomatic adults with normal spirometry, and to generate a tool to help clinicians decide who should undergo bronchial challenge testing (BCT). METHODS: Using random-digit dialling and population-based case-finding, we recruited adults from the community with respiratory symptoms and no previous history of diagnosed lung disease. Participants with normal pre- and post-bronchodilator spirometry subsequently underwent BCT. Asthma was diagnosed in those with symptoms and a methacholine provocative concentration (PC20) of < 8 mg/ml. Sputum and blood eosinophils, and exhaled nitric oxide were measured. Univariate analyses identified potentially predictive variables, which were then used to construct a multivariable logistic regression model to predict asthma. Model sensitivity, specificity, and area under the receiver operating curve (AUC) were calculated. RESULTS: Of 132 symptomatic individuals with normal spirometry, 34 (26%) had asthma. Of those ultimately diagnosed with asthma, 33 (97%) answered 'yes' to a question asking whether they experienced cough, chest tightness or wheezing provoked by exercise or cold air. Other univariate predictors of asthma included female sex, pre-bronchodilator FEV1 percentage predicted, and percent positive change in FEV1 post bronchodilator. A multivariable model containing these predictive variables yielded an AUC of 0.82 (95% CI: 0.72-0.91), a sensitivity of 82%, and a specificity of 66%. The model was used to construct a nomogram to advise clinicians which patients should be prioritized for BCT. CONCLUSIONS: Four readily available patient characteristics demonstrated a high sensitivity and AUC for predicting undiagnosed asthma in symptomatic adults with normal pre- and post-bronchodilator spirometry. These characteristics can potentially help clinicians to decide which individuals with normal spirometry should be investigated with bronchial challenge testing. However, further prospective validation of our decision tool is required.


Assuntos
Asma , Broncodilatadores , Adulto , Feminino , Humanos , Asma/diagnóstico , Brônquios , Testes de Provocação Brônquica , Volume Expiratório Forçado , Cloreto de Metacolina , Espirometria
4.
Cleft Palate Craniofac J ; : 10556656231214131, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37968856

RESUMO

OBJECTIVE: The purpose of this study was to investigate the contribution of MSX1 gene polymorphisms to the risk of developing NSCLP. DESIGN: Case-Control Study. SETTING: A tertiary care centre. PATIENTS/PARTICIPANTS: The sample consisted of 200 subjects (100 cases and 100 controls). INTERVENTIONS: None. MAIN OUTCOME MEASURE(S): Genotyping was performed by restriction fragment length polymorphism. Allele and genotype frequencies were calculated between patients and controls and analyzed using online Web Tools such as SISA and SNPstats. The MSX1 gene polymorphisms c. 799 GT, c.458 CA can be risk factors in the development of orofacial clefts. RESULTS: In the cases, an association was found between NSCLP and c.799 and c.458 of the MSX1 gene when compared with the control. The dominant and overdominant models, c. 799 GT, c.458 CA genotypes and c. 799 T, c.458 A alleles in the population are said to be the main risk factors to develop the NSCLP in our study population. The genotype variation of c 799 G/T and c.458 C/A are revealed to be specifically contributing to an NSCLP-type Cleft lip and Palate. It is worth noting that NSCLP females in the study population showed a stronger association with heterozygous genotypes of c.799 and c.458. However, further investigation with a larger cohort is necessary to confirm these findings. CONCLUSION: Overall the results of the study revealed that MSX1 c 799 G > T and c.458 C > A can be considered as one of the genetic risk factors in the formation of Non-Syndromic Cleft Lip and Palate in the study population.

5.
Semin Cancer Biol ; 69: 349-364, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32088362

RESUMO

Lung cancer is the second most common cancer and the leading cause of death in both men and women in the world. Lung cancer is heterogeneous in nature and diagnosis is often at an advanced stage as it develops silently in the lung and is frequently associated with high mortality rates. Despite the advances made in understanding the biology of lung cancer, progress in early diagnosis, cancer therapy modalities and considering the mechanisms of drug resistance, the prognosis and outcome still remains low for many patients. Nanotechnology is one of the fastest growing areas of research that can solve many biological problems such as cancer. A growing number of therapies based on using nanoparticles (NPs) have successfully entered the clinic to treat pain, cancer, and infectious diseases. Recent progress in nanotechnology has been encouraging and directed to developing novel nanoparticles that can be one step ahead of the cancer reducing the possibility of multi-drug resistance. Nanomedicine using NPs is continuingly impacting cancer diagnosis and treatment. Chemotherapy is often associated with limited targeting to the tumor, side effects and low solubility that leads to insufficient drug reaching the tumor. Overcoming these drawbacks of chemotherapy by equipping NPs with theranostic capability which is leading to the development of novel strategies. This review provides a synopsis of current progress in theranostic applications for lung cancer diagnosis and therapy using NPs including liposome, polymeric NPs, quantum dots, gold NPs, dendrimers, carbon nanotubes and magnetic NPs.


Assuntos
Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamento farmacológico , Nanomedicina , Nanopartículas/administração & dosagem , Animais , Humanos , Nanopartículas/química
6.
Molecules ; 27(17)2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36080424

RESUMO

Heavy metals and metalloids like cadmium, arsenic, mercury, and lead are frequently found in the soil, water, food, and atmosphere; trace amounts can cause serious health issues to the human organism. These toxic trace elements (TTE) affect almost all the organs, mainly the heart, kidney, liver, lungs, and the nervous system, through increased free radical formation, DNA damage, lipid peroxidation, and protein sulfhydryl depletion. This work aims to advance our understanding of the mechanisms behind lipid accumulation via increased free fatty acid levels in circulation due to TTEs. The increased lipid level in the myocardium worsens the heart function. This dysregulation of the lipid metabolism leads to damage in the structure of the myocardium, inclusive fibrosis in cardiac tissue, myocyte apoptosis, and decreased contractility due to mitochondrial dysfunction. Additionally, it is discussed herein how exposure to cadmium decreases the heart rate, contractile tension, the conductivity of the atrioventricular node, and coronary flow rate. Arsenic may induce atherosclerosis by increasing platelet aggregation and reducing fibrinolysis, as exposure interferes with apolipoprotein (Apo) levels, resulting in the rise of the Apo-B/Apo-A1 ratio and an elevated risk of acute cardiovascular events. Concerning mercury and lead, these toxicants can cause hypertension, myocardial infarction, and carotid atherosclerosis, in association with the generation of free radicals and oxidative stress. This review offers a complete overview of the critical factors and biomarkers of lipid and TTE-induced cardiotoxicity useful for developing future protective interventions.


Assuntos
Arsênio , Mercúrio , Metais Pesados , Oligoelementos , Arsênio/toxicidade , Cádmio/toxicidade , Humanos , Lipídeos , Mercúrio/toxicidade , Metais Pesados/química , Oligoelementos/toxicidade
7.
Echocardiography ; 38(2): 189-196, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33336441

RESUMO

BACKGROUND: Diastolic dysfunction (DD) and pulmonary hypertension (PH) are common causes of mortality for sickle cell disease (SCD) patients in developed countries. We hypothesized that left and right atrial strain (LAS-Ɛ, RAS-rƐ) are decreased in SCD adolescents, and that worsening values correlate with laboratory markers of disease severity. METHODS: Prospective cohort study of patients with HbSS genotype of SCD was compared with healthy controls. LAS and RAS were measured from 4- and 2-chamber views by a blinded reader. Peak strain and strain rate values were obtained for atrial contraction (ac), reservoir (res), and conduit (con) phases. Mitral/tricuspid Doppler velocities, left atrial volume, right atrial area were obtained. Laboratory variables were obtained from the electronic record with the three prior values being averaged. Differences in variables were assessed with Wilcoxon rank sum test, and correlations assessed with Spearman's coefficient. RESULTS: There were 33 SCD patients compared to 35 healthy controls of similar age, gender, and size. SCD patients had increased left atrial volume and right atrial area. For LAS, Ɛres was significantly lower in SCD patients. For RAS, RƐcon was significantly lower. Neither measurement correlated with clinical markers. The majority of SCD patients had relatively normal atrial strain values. Those with markedly lower values had similar atrial size. CONCLUSIONS: A sub-set of SCD patients have markedly low Ɛres and rƐcon. No correlation with clinical markers was identified. Larger, longitudinal studies may determine utility of atrial strain as a screening tool in this at-risk population.


Assuntos
Anemia Falciforme , Disfunção Ventricular Esquerda , Adolescente , Anemia Falciforme/complicações , Anemia Falciforme/diagnóstico por imagem , Função do Átrio Esquerdo , Criança , Dilatação , Átrios do Coração/diagnóstico por imagem , Humanos , Estudos Prospectivos
8.
JAMA ; 325(15): 1513-1523, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33877274

RESUMO

Importance: Although effective agents are available to prevent painful vaso-occlusive episodes of sickle cell disease (SCD), there are no disease-modifying therapies for ongoing painful vaso-occlusive episodes; treatment remains supportive. A previous phase 3 trial of poloxamer 188 reported shortened duration of painful vaso-occlusive episodes in SCD, particularly in children and participants treated with hydroxyurea. Objective: To reassess the efficacy of poloxamer 188 for vaso-occlusive episodes. Design, Setting, and Participants: Phase 3, randomized, double-blind, placebo-controlled, multicenter, international trial conducted from May 2013 to February 2016 that included 66 hospitals in 12 countries and 60 cities; 388 individuals with SCD (hemoglobin SS, SC, S-ß0 thalassemia, or S-ß+ thalassemia disease) aged 4 to 65 years with acute moderate to severe pain typical of painful vaso-occlusive episodes requiring hospitalization were included. Interventions: A 1-hour 100-mg/kg loading dose of poloxamer 188 intravenously followed by a 12-hour to 48-hour 30-mg/kg/h continuous infusion (n = 194) or placebo (n = 194). Main Outcomes and Measures: Time in hours from randomization to the last dose of parenteral opioids among all participants and among those younger than 16 years as a separate subgroup. Results: Of 437 participants assessed for eligibility, 388 were randomized (mean age, 15.2 years; 176 [45.4%] female), the primary outcome was available for 384 (99.0%), 15-day follow-up contacts were available for 357 (92.0%), and 30-day follow-up contacts were available for 368 (94.8%). There was no significant difference between the groups for the mean time to last dose of parenteral opioids (81.8 h for the poloxamer 188 group vs 77.8 h for the placebo group; difference, 4.0 h [95% CI, -7.8 to 15.7]; geometric mean ratio, 1.2 [95% CI, 1.0-1.5]; P = .09). Based on a significant interaction of age and treatment (P = .01), there was a treatment difference in time from randomization to last administration of parenteral opioids for participants younger than 16 years (88.7 h in the poloxamer 188 group vs 71.9 h in the placebo group; difference, 16.8 h [95% CI, 1.7-32.0]; geometric mean ratio, 1.4 [95% CI, 1.1-1.8]; P = .008). Adverse events that were more common in the poloxamer 188 group than the placebo group included hyperbilirubinemia (12.7% vs 5.2%); those more common in the placebo group included hypoxia (12.0% vs 5.3%). Conclusions and Relevance: Among children and adults with SCD, poloxamer 188 did not significantly shorten time to last dose of parenteral opioids during vaso-occlusive episodes. These findings do not support the use of poloxamer 188 for vaso-occlusive episodes. Trial Registration: ClinicalTrials.gov Identifier: NCT01737814.


Assuntos
Anemia Falciforme/tratamento farmacológico , Dor/tratamento farmacológico , Poloxâmero/uso terapêutico , Vasodilatadores/uso terapêutico , Adolescente , Adulto , Analgésicos Opioides/uso terapêutico , Anemia Falciforme/complicações , Criança , Método Duplo-Cego , Feminino , Humanos , Masculino , Dor/etiologia , Placebos/efeitos adversos , Placebos/uso terapêutico , Poloxâmero/efeitos adversos , Vasodilatadores/efeitos adversos , Adulto Jovem
9.
J Environ Manage ; 297: 113347, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34314963

RESUMO

In the current scenario, the word waste management holds much importance in every individual's life. Pollution and the generation of vast waste quantities with no proper waste management process have become one of humanity's biggest threats. This review article provides a complete review of the innovative technologies currently employed to handle and dispose of the waste successfully. This work aims to include the different solid, liquid, gaseous, and radioactive waste management processes. The novel and improved plasma gasification concepts, transmutation, incineration, bio-refineries, microbial fuel cells (MFC) have been thoroughly explained. In addition, some new techniques like Mr. Trash Wheel and the Smart bin approach provide much hope of adequately managing waste. The work's novelty lies in adopting several successful methods of various countries for waste disposal and management. To incorporate or improve India'sIndia's same techniques and processes, we have to tackle the ever-increasing waste disposal problems and find economic and eco-friendly ways of waste management.


Assuntos
Eliminação de Resíduos , Gerenciamento de Resíduos , Incineração , Resíduos Sólidos , Tecnologia
10.
Optom Vis Sci ; 97(8): 648-653, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32833408

RESUMO

SIGNIFICANCE: The performance of resistance exercise has evidenced to induce abrupt intraocular pressure (IOP) changes, which has been linked to the onset and progression of glaucoma. We found that four different isometric resistance exercises lead to an instantaneous and progressive IOP elevation, with these changes being independent of the type of exercise. PURPOSE: The impact of physical exercise on IOP has demonstrated to be dependent on exercise type and intesity, as well as individuals' characteristics. In this study, we aimed to explore the influence of the load, exercise type, and participant's sex on the IOP behavior during a 2-minute isometric effort. METHODS: Twenty-eight physically active collegiate students performed 2 minutes of isometric exercise in the military press, biceps curl, leg extension, and calf raise exercises against two different loads (high load and low load). Intraocular pressure was measured by rebound tonometry before, during (semicontinuos assessment [24 measurements]), and after 10 seconds of recovery in each of the eight (four exercises × two loads) conditions. RESULTS: We found a statistically significant effect of load (P < .001, np = 0.906), with greater IOP values when performing the isometric exercises against heavier loads. There was a positive IOP rise during the execution of isometric exercise in the high-load condition, returning to baseline levels after 10 seconds of passive recovery. The exercise type and participant's sex did not reveal statistically significant differences (P = .33 and P = .56, respectively). CONCLUSIONS: Our data evidenced an instanteneous and progressive IOP rise during the execution of isometric exercise leading to muscular failure, regardless of the exercise type and participant's sex. After exercise, IOP rapidly retuned to baseline levels (within 10 seconds). The inclusion of glaucoma patients in future studies is guarranteed.


Assuntos
Exercício Físico/fisiologia , Pressão Intraocular/fisiologia , Adulto , Feminino , Humanos , Masculino , Tonometria Ocular , Adulto Jovem
11.
Circ Res ; 120(4): 701-712, 2017 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-27872050

RESUMO

RATIONALE: Studies have demonstrated that exosomes can repair cardiac tissue post-myocardial infarction and recapitulate the benefits of cellular therapy. OBJECTIVE: We evaluated the role of donor age and hypoxia of human pediatric cardiac progenitor cell (CPC)-derived exosomes in a rat model of ischemia-reperfusion injury. METHODS AND RESULTS: Human CPCs from the right atrial appendages from children of different ages undergoing cardiac surgery for congenital heart defects were isolated and cultured under hypoxic or normoxic conditions. Exosomes were isolated from the culture-conditioned media and delivered to athymic rats after ischemia-reperfusion injury. Echocardiography at day 3 post-myocardial infarction suggested statistically improved function in neonatal hypoxic and neonatal normoxic groups compared with saline-treated controls. At 28 days post-myocardial infarction, exosomes derived from neonatal normoxia, neonatal hypoxia, infant hypoxia, and child hypoxia significantly improved cardiac function compared with those from saline-treated controls. Staining showed decreased fibrosis and improved angiogenesis in hypoxic groups compared with controls. Finally, using sequencing data, a computational model was generated to link microRNA levels to specific outcomes. CONCLUSIONS: CPC exosomes derived from neonates improved cardiac function independent of culture oxygen levels, whereas CPC exosomes from older children were not reparative unless subjected to hypoxic conditions. Cardiac functional improvements were associated with increased angiogenesis, reduced fibrosis, and improved hypertrophy, resulting in improved cardiac function; however, mechanisms for normoxic neonatal CPC exosomes improved function independent of those mechanisms. This is the first study of its kind demonstrating that donor age and oxygen content in the microenvironment significantly alter the efficacy of human CPC-derived exosomes.


Assuntos
Exossomos/fisiologia , MicroRNAs/fisiologia , Miócitos Cardíacos/fisiologia , Traumatismo por Reperfusão/terapia , Células-Tronco/fisiologia , Fatores Etários , Animais , Hipóxia Celular/fisiologia , Células Cultivadas , Criança , Pré-Escolar , Compreensão , Método Duplo-Cego , Exossomos/transplante , Humanos , Lactente , Recém-Nascido , MicroRNAs/administração & dosagem , Miócitos Cardíacos/transplante , Distribuição Aleatória , Ratos , Ratos Nus , Traumatismo por Reperfusão/fisiopatologia , Transplante de Células-Tronco/métodos
12.
Xenobiotica ; 49(4): 415-421, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29642738

RESUMO

Development of prodrug of 9-hydroxyrisperidone (paliperidone) long-acting intramuscular injection has enabled delivery over four-week time period with improved compliance. The key aim of this work was to establish a reliable preclinical model which may potentially serve as a screening tool for judging the pharmacokinetics of paliperidone formulation(s) prior to human clinical work. Sparse sampling composite study was used in rats, (Wistar/Sprague-Dawley (SD; n = 10)) and a serial blood sampling study design was used in rabbits (n = 4). Animals received intramuscular injection of paliperidone palmitate in the thigh muscle at dose of 16 (rats) and 4.5 mg/kg (rabbits). Samples were drawn in rats (retro-orbital sinus) and rabbits (central ear artery) and were analysed for paliperidone using liquid chromatography-mass spectrometry/ mass spectrometry (LC-MS/MS) assay. The plasma data was subjected to pharmacokinetic analysis. Following intramuscular injection of depot formulation in Wistar/SD rats and rabbits, absorption of paliperidone was slow and gradual with median value of time to reach maximum concentration (Tmax) occurring on day 7. The exposures (i.e. area under the curve (AUC; 0-28) days) were 18,597, 21,865 and 18,120 ng.h/mL, in Wistar, SD and rabbits, respectively. The clearance was slow and supported long half-life (8-10 days). Either one of the two models can serve as a research tool for establishing pharmacokinetics of paliperidone formulation(s).


Assuntos
Avaliação Pré-Clínica de Medicamentos , Músculo Esquelético/metabolismo , Palmitato de Paliperidona/farmacocinética , Animais , Relação Dose-Resposta a Droga , Masculino , Músculo Esquelético/efeitos dos fármacos , Palmitato de Paliperidona/administração & dosagem , Palmitato de Paliperidona/sangue , Palmitato de Paliperidona/química , Coelhos , Ratos Sprague-Dawley
13.
Andrologia ; 51(9): e13377, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31361042

RESUMO

The SRY gene is considered as the key player in the male sexual differentiation and developmental pathway. SRY gene mutations account for ~15% of 46,XY disorders of sexual development patients, and majority of them resides within the HMG domain of the protein. In this study, we report a novel missense mutation within the HMG domain of SRY gene, and an A-to-T transition causes E89V amino acid substitution in a 15-year-old female patient with 46,XY karyotype and complete gonadal dysgenesis. Moreover, three-dimensional analysis of protein-DNA complex showed that the replacement of highly hydrophilic glutamic acid residue with a hydrophobic residue like valine would have an impact on the structure of protein. In conclusion, we identified a novel SRY mutation in a 46,XY female patient with complete gonadal dysgenesis, and based on the protein modelling, we propose that the identified mutation could impair normal function of the SRY protein.


Assuntos
Disgenesia Gonadal 46 XY/genética , Proteína da Região Y Determinante do Sexo/genética , Adolescente , Substituição de Aminoácidos , Análise Mutacional de DNA , Disgenesia Gonadal 46 XY/diagnóstico , Humanos , Masculino , Mutação Puntual
14.
J Sports Sci ; 37(19): 2213-2219, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31177968

RESUMO

We assessed the intraocular pressure (IOP) behaviour during a 1-minute period of isometric physical effort and the immediate 1-minute of recovery in the mid-thigh clean pull and squat exercises at three different intensities. Twenty physically active individuals performed the isometric mid-thigh clean pull and squat exercises at three intensities (0% [low-intensity], 25% [medium-intensity] and 50% [high-intensity] of the maximum isometric force). IOP was semi-continuously measured by rebound tonometry. There was a statistically significant effect of exercise intensity on IOP (p < 0.001, ƞp² = 0.416), observing that IOP increments were positively associated with exercise intensity. The mid-thigh clean pull and squat exercises did not demonstrate differences (p = 0.510), and also, no differences were observed between men and women (p = 0.683). The IOP changes during the isometric physical effort showed a positive linear behaviour in all conditions (r = 0.70 to 0.96). IOP returned to baseline levels after 8 seconds of recovery.  Our data showed a progressive and instantaneous IOP increment during isometric exercise, which was positively associated with exercise intensity. IOP changes were independent on the type of exercise and participant´s sex. After exercise, IOP rapidly (≈ 8 seconds) returned to baseline levels.


Assuntos
Exercício Físico/fisiologia , Pressão Intraocular/fisiologia , Levantamento de Peso/fisiologia , Adulto , Feminino , Humanos , Masculino , Treinamento Resistido , Fatores Sexuais , Adulto Jovem
15.
Sensors (Basel) ; 19(2)2019 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-30669382

RESUMO

In the last few years, one of the main characteristics of the current technological development is the constantly increasing need for data exchange among various types of devices, both mobile and fixed. Within this context, the direct communications between devices has the potential to create new, location-based peer-to-peer applications and services, as well as to help offload traffic from the congested traditional cellular networks. The main hurdles for this kind of Device to Device (D2D) communications are throughput, spectral efficiency, latency and fairness. Most of these hurdles can be overcome by the use of the new Social IoT (SIoT) paradigm, of things and people involved together in the network, guided autonomously by social relationships following the rules set by their owners. This paper aims to investigate the state of the art of socially-driven D2D communications. Upon an initial analysis, we perform an in-deep literature investigation of the main directions in which social ties can improve D2D communication, draw conclusions and identify the research topics left open.


Assuntos
Redes de Comunicação de Computadores , Rede Social , Inquéritos e Questionários , Algoritmos , Humanos
16.
Transfusion ; 58(3): 726-735, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29210071

RESUMO

BACKGROUND: Hyperhemolysis syndrome (HHS) is an uncommon, but life-threatening, transfusion-related complication of red blood cell transfusion. HHS has predominantly been described in patients with sickle cell disease (SCD) and is difficult to diagnose and treat. The pathogenesis of HHS, including its occurrence in only a subset of apparently susceptible individuals, is poorly understood. We undertook whole-exome sequencing (WES) of 12 SCD-HHS patients to identify shared genetic variants that might be relevant to the development of HHS. STUDY DESIGN AND METHODS: DNA from adults with SCD having at least one previous episode of HHS were subject to WES. High-quality variants were passed through a series of bioinformatics filters to identify variants that were uncommon among African populations represented in public databases. Recurrent, putative loss-of-function variants occurring in biologically plausible genes were prioritized and then genotyped in a larger, ancestry-matched cohort of non-HHS controls. RESULTS: A rare, heterozygous stop-gain variant (p.Glu210Ter) in MBL2 was significantly enriched among HHS cases (p = 0.002). This variant is predicted to result in a premature termination codon that escapes nonsense-mediated mRNA decay, potentially leading to a novel phenotype. We also observed a complex insertion-deletion variant in the final exon of KLRC3 that was enriched among cases (p = 0.0019), although neither variant was found among seven pediatric SCD-HHS patients. CONCLUSION: Our results suggest a potential role for rare genetic defects in the development of HHS among adult SCD patients. Such enriched variants may ultimately be useful for identifying high-risk individuals and informing therapeutic approaches in HHS.


Assuntos
Anemia Falciforme , Exoma , Predisposição Genética para Doença , Variação Genética , Hemólise/genética , Adolescente , Adulto , Anemia Falciforme/complicações , Anemia Falciforme/genética , Criança , Pré-Escolar , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Síndrome
17.
Bioorg Med Chem ; 26(8): 1481-1487, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29456113

RESUMO

Androgen receptor (AR) signaling is vital to the viability of all forms of prostate cancer (PCa). With the goal of investigating the effect of simultaneous inhibition and depletion of AR on viability of PCa cells, we designed, synthesized and characterized the bioactivities of bifunctional agents which incorporate the independent cancer killing properties of an antiandrogen and genistein, and the AR downregulation effect of genistein within a single molecular template. We observed that a representative conjugate, 9b, is much more cytotoxic to both LNCaP and DU145 cells relative to the antiandrogen and genistein building blocks as single agents or their combination. Moreover, conjugate 9b more effectively down regulates cellular AR protein levels relative to genistein and induces S phase cell cycle arrest. The promising bioactivities of these conjugates warrant further investigation.


Assuntos
Antagonistas de Androgênios/farmacologia , Antineoplásicos/farmacologia , Desenho de Fármacos , Genisteína/farmacologia , Hidantoínas/farmacologia , Antagonistas de Androgênios/síntese química , Antagonistas de Androgênios/química , Antineoplásicos/síntese química , Antineoplásicos/química , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Genisteína/síntese química , Genisteína/química , Humanos , Hidantoínas/química , Estrutura Molecular , Receptores Androgênicos/metabolismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
18.
Lancet ; 387(10019): 661-670, 2016 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-26670617

RESUMO

BACKGROUND: For children with sickle cell anaemia and high transcranial doppler (TCD) flow velocities, regular blood transfusions can effectively prevent primary stroke, but must be continued indefinitely. The efficacy of hydroxycarbamide (hydroxyurea) in this setting is unknown; we performed the TWiTCH trial to compare hydroxyurea with standard transfusions. METHODS: TWiTCH was a multicentre, phase 3, randomised, open-label, non-inferiority trial done at 26 paediatric hospitals and health centres in the USA and Canada. We enrolled children with sickle cell anaemia who were aged 4-16 years and had abnormal TCD flow velocities (≥ 200 cm/s) but no severe vasculopathy. After screening, eligible participants were randomly assigned 1:1 to continue standard transfusions (standard group) or hydroxycarbamide (alternative group). Randomisation was done at a central site, stratified by site with a block size of four, and an adaptive randomisation scheme was used to balance the covariates of baseline age and TCD velocity. The study was open-label, but TCD examinations were read centrally by observers masked to treatment assignment and previous TCD results. Participants assigned to standard treatment continued to receive monthly transfusions to maintain 30% sickle haemoglobin or lower, while those assigned to the alternative treatment started oral hydroxycarbamide at 20 mg/kg per day, which was escalated to each participant's maximum tolerated dose. The treatment period lasted 24 months from randomisation. The primary study endpoint was the 24 month TCD velocity calculated from a general linear mixed model, with the non-inferiority margin set at 15 cm/s. The primary analysis was done in the intention-to-treat population and safety was assessed in all patients who received at least one dose of assigned treatment. This study is registered with ClinicalTrials.gov, number NCT01425307. FINDINGS: Between Sept 20, 2011, and April 17, 2013, 159 patients consented and enrolled in TWiTCH. 121 participants passed screening and were then randomly assigned to treatment (61 to transfusions and 60 to hydroxycarbamide). At the first scheduled interim analysis, non-inferiority was shown and the sponsor terminated the study. Final model-based TCD velocities were 143 cm/s (95% CI 140-146) in children who received standard transfusions and 138 cm/s (135-142) in those who received hydroxycarbamide, with a difference of 4·54 (0·10-8·98). Non-inferiority (p=8·82 × 10(-16)) and post-hoc superiority (p=0·023) were met. Of 29 new neurological events adjudicated centrally by masked reviewers, no strokes were identified, but three transient ischaemic attacks occurred in each group. Magnetic resonance brain imaging and angiography (MRI and MRA) at exit showed no new cerebral infarcts in either treatment group, but worsened vasculopathy in one participant who received standard transfusions. 23 severe adverse events in nine (15%) patients were reported for hydroxycarbamide and ten serious adverse events in six (10%) patients were reported for standard transfusions. The most common serious adverse event in both groups was vaso-occlusive pain (11 events in five [8%] patients with hydroxycarbamide and three events in one [2%] patient for transfusions). INTERPRETATION: For high-risk children with sickle cell anaemia and abnormal TCD velocities who have received at least 1 year of transfusions, and have no MRA-defined severe vasculopathy, hydroxycarbamide treatment can substitute for chronic transfusions to maintain TCD velocities and help to prevent primary stroke. FUNDING: National Heart, Lung, and Blood Institute, National Institutes of Health.


Assuntos
Anemia Falciforme/tratamento farmacológico , Antidrepanocíticos/uso terapêutico , Transfusão de Sangue/métodos , Hidroxiureia/uso terapêutico , Adolescente , Anemia Falciforme/fisiopatologia , Velocidade do Fluxo Sanguíneo , Circulação Cerebrovascular/fisiologia , Criança , Pré-Escolar , Terapia Combinada , Substituição de Medicamentos , Feminino , Humanos , Masculino , Acidente Vascular Cerebral/etiologia , Resultado do Tratamento , Ultrassonografia Doppler Transcraniana
19.
Am J Hematol ; 92(9): E520-E528, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28589652

RESUMO

Nephropathy is a common and progressive complication of sickle cell anemia (SCA). In SCA mice, we found that hyperangiotensinemia in the absence of hypertension underlies nephropathy, and its downregulation by losartan, an angiotensin-II-receptor-1 blocker, reduced albuminuria and progression of nephropathy. Therefore, we performed a phase-2 trial of oral losartan, given for 6 months, to explore whether it reduced albuminuria in children and adults with SCA. Participants were allocated to groups defined by class of baseline urinary albumin-to-creatinine ratio (UACR): no albuminuria (NoA), microalbuminuria (MicroA), and macroalbuminuria (MacroA). The primary endpoint was a ≥25% reduction UACR from baseline. There were 32 evaluable participants (mean age 24 years; NoA = 14, MicroA = 12, MacroA = 6). The primary endpoint was met in 83% of the MacroA group (P < 0.0001) and 58% of the MicroA group (P < 0.0001). Median fold-change in UACR was -0.74 for MacroA and -0.46 for MicroA. In MacroA and MicroA, UACR classification improved in 50% but worsened in 11%. Urine osmolality and estimated glomerular filtration rate (eGFR) did not change significantly. Losartan was discontinued in three participants [leg cramps, N = 1; decline in eGFR >25% (142➝104 mL/minute/1.73 m2 ), N = 1; rise in serum creatinine >50% (0.2➝0.3 mg/dL), N = 1]. Albuminuria was associated with diastolic dysfunction and impaired functional capacity, although cardiopulmonary status was unchanged after 6 months of losartan therapy. In summary, losartan decreased urinary albumin excretion in most participants with albuminuria. Those with macroalbuminuria had the greatest benefit. This study forms the basis for a phase-3, randomized, placebo-controlled trial of losartan for the nephropathy of SCA.


Assuntos
Albuminúria , Anemia Falciforme , Losartan/administração & dosagem , Adolescente , Adulto , Fatores Etários , Albuminúria/tratamento farmacológico , Albuminúria/etiologia , Albuminúria/fisiopatologia , Albuminúria/urina , Anemia Falciforme/complicações , Anemia Falciforme/tratamento farmacológico , Anemia Falciforme/fisiopatologia , Anemia Falciforme/urina , Criança , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade
20.
Clin Transplant ; 31(6)2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28267234

RESUMO

BACKGROUND: We previously identified factors associated with a greater risk of death post-transplant. The purpose of this study was to develop a clinical tool to estimate the risk of death after transplant based on pre-transplant variables. METHODS: We utilized the Canadian CF registry to develop a nomogram that incorporates pre-transplant clinical measures to assess post-lung transplant survival. The 1-, 3-, and 5-year survival estimates were calculated using Cox proportional hazards models. RESULTS: Between 1988 and 2012, 539 adult Canadians with CF received a lung transplant with 208 deaths in the study period. Four pre-transplant factors most predictive of poor post-transplant survival were older age at transplantation, infection with B. cepacia complex, low FEV1 percent predicted, and pancreatic sufficiency. A nonlinear relationship was found between risk of death and FEV1 percent predicted, age at transplant, and BMI. We constructed a risk calculator based on our model to estimate the 1-, 3-, and 5-year probability of survival after transplant which is available online. CONCLUSIONS: Our risk calculator quantifies the risk of death associated with lung transplant using pre-transplant factors. This tool could aid clinicians and patients in the decision-making process and provide information regarding the timing of lung transplantation.


Assuntos
Fibrose Cística/cirurgia , Rejeição de Enxerto/mortalidade , Transplante de Pulmão/mortalidade , Complicações Pós-Operatórias/mortalidade , Adolescente , Adulto , Feminino , Seguimentos , Volume Expiratório Forçado , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Humanos , Transplante de Pulmão/efeitos adversos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Taxa de Sobrevida , Adulto Jovem
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