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The objective of the study was to report our institutional experience in the management of children and newborns with refractory septic shock who required venoarterial extracorporeal membrane oxygenation (VA ECMO) treatment, and to identify patient-and infection-related factors associated with mortality. This is a retrospective case series in an intensive care unit of a tertiary pediatric center. Inclusion criteria were patients ≤ 18 years old who underwent a VA ECMO due to a refractory septic shock due to circulatory collapse. Patient conditions and support immediately before ECMO, analytical and hemodynamic parameter evolution during ECMO, and post-canulation outcome data were collected. Twenty-one patients were included, 13 of them (65%) male. Nine were pediatric and 12 were newborns. Median septic shock duration prior to ECMO was 29.5 h (IQR, 20-46). Eleven patients (52.4%) suffered cardiac arrest (CA). Neonatal patients had worse Sepsis Organ Failure Assessment (SOFA) score, Oxygenation Index and PaO2/FiO2 ratio, blood gas analysis, lactate levels, and left ventricular ejection fraction compared to pediatric patients. Survival was 33.3% among pediatric patients (60% if we exclude pneumococcal cases) and 50% among newborns. Hours of sepsis evolution and mean airway pressure (MAP) prior to ECMO were significantly higher in the non-survivor group. CA was not a predictor of mortality. Streptococcus pneumoniae infection was a mortality risk factor. There was an improvement in survival during the second period, from 14.3 to 57.2%, related to shorter sepsis evolution before ECMO placement, better candidate selection, and greater ECMO support once the patient was placed. CONCLUSION: Patients with refractory septic shock should be transferred precociously to a referral ECMO center. However, therapy should be used with caution in patients with vasoplegic pattern shock or S. pneumoniae sepsis. What is Known: ⢠Children with refractory septic shock have significant mortality rates, and although ECMO is recommended, overall survival is low. ⢠There are no studies regarding characteristics of infections as predictors of pediatric survival in ECMO. What is New: ⢠Septic children should be transferred precociously to referral ECMO centers during the first hours if patients do not respond to conventional therapy. ⢠Treatment should be used with caution in patients with vasoplegic pattern shock or S. pneumoniae sepsis.
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Oxigenação por Membrana Extracorpórea/métodos , Choque Séptico/terapia , Adolescente , Criança , Pré-Escolar , Cuidados Críticos/métodos , Feminino , Humanos , Lactente , Recém-Nascido , Modelos Logísticos , Masculino , Estudos Retrospectivos , Choque Séptico/complicações , Choque Séptico/mortalidade , Resultado do TratamentoRESUMO
Nowadays, the modulation of gene expression by nucleic acids has become a routine tool in biomedical research for target validation and it is also used to develop new therapeutic approaches. Recently, we developed the so-called polypurine reverse Hoogsteen hairpins (PPRHs) that show high stability and a low immunogenic profile and we demonstrated their efficacy both in vitro and in vivo. In this work, we explored different characteristics of PPRHs to improve their usage as a tool for gene silencing. We studied the role of PPRH length in the range from 20 to 30 nucleotides. We also proved their higher affinity of binding and efficacy on cell viability compared to nonmodified TFOs. To overcome possible off-target effects, we tested wild-type PPRHs, which proved to be capable of binding to their target sequence with more affinity, displaying a higher stability of binding and a higher effect in terms of cell viability. Moreover, we developed a brand new molecule called Wedge-PPRH with the ability to lock the ds-DNA into the displaced structure and proved its efficacy in prostate and breast cancer cell lines.
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Inativação Gênica , Sequências Repetidas Invertidas/genética , Biofarmácia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/terapia , Linhagem Celular Tumoral , Sobrevivência Celular , DNA/química , DNA/genética , Desenho de Fármacos , Feminino , Engenharia Genética , Humanos , Proteínas Inibidoras de Apoptose/genética , Masculino , Conformação de Ácido Nucleico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/terapia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Survivina , Telomerase/genéticaRESUMO
PURPOSE: To evaluate the effect of cocoa flavonoids in breast cancer cells at the molecular level, a functional genomic analysis was performed using a polyphenolic cocoa extract (PCE) in MCF-7 and SKBR3 cell lines. METHODS: The expression profile of 84 genes included in the Stress & Toxicity PathwayFinder™ PCR Array was analyzed after PCE incubation for 24 h. mRNA and protein levels were analyzed by RT-PCR and western blot, respectively. Gel shift assays were used to evaluate DNA-protein complexes. Protein complexes were identified by co-immunoprecipitation. Cell viability was evaluated by MTT assays. RESULTS: Upon PCE incubation, 7 genes were overexpressed and 1 underexpressed in MCF-7 cells, whereas 9 genes were overexpressed in SKBR3 cells. Among the differentially expressed genes in both cell lines, cytochrome P450, family 1, subfamily A, polypeptide 1 (CYP1A1) was chosen for further study. CYP1A1 mRNA and protein levels and enzymatic activity increased upon PCE incubation. CYP1A1 transcriptional activation by PCE was mediated through AhR binding to XRE elements within the CYP1A1 promoter in MCF-7 cells. A protein complex including AhR and ERα was detected. The combination of PCE with tamoxifen caused a synergistic cytotoxicity in both cell lines and was due to an increase in apoptosis in MCF-7 cells. CONCLUSIONS: The interaction between ERα and AhR upon incubation with PCE leads to CYP1A1 induction in breast cancer cells. The synergy between PCE and non-cytotoxic tamoxifen concentrations opens the possibility for a combination therapy based on polyphenols from cocoa that increased tamoxifen efficacy.
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Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/enzimologia , Cacau/química , Citocromo P-450 CYP1A1/biossíntese , Flavonoides/farmacologia , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/química , Antioxidantes/química , Antioxidantes/farmacologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citocromo P-450 CYP1A1/genética , Sinergismo Farmacológico , Indução Enzimática/efeitos dos fármacos , Receptor alfa de Estrogênio/metabolismo , Feminino , Flavonoides/análise , Perfilação da Expressão Gênica , Humanos , Extratos Vegetais/química , RNA Mensageiro/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Elementos de Resposta/efeitos dos fármacos , Sementes/química , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Tamoxifeno/farmacologiaRESUMO
INTRODUCTION: Postoperative exercise improves arteriovenous fistula maturation for hemodialysis. However, scarce evidence exists about hand grip device on fistula maturation process. OBJECTIVE: To evaluate the efficacy of a hand grip training program on arteriovenous fistula maturation in population with Chronic Kidney Disease 5-5D. METHODOLOGY: Prospective study (15 months). Patients were randomized to handgrip (HG) or control group (CG) postoperatively. HG performed a training program using a hand grip device. CG received conventional care. Upper limb muscle strength (ULMS), Duplex ultrasonography, and clinical arteriovenous fistula maturation were assessed at 4 and 8 weeks postoperatively. RESULTS: At 8 weeks after fistula creation, upper limb muscle strength was increased only in the handgrip group (from 18 ± 6 to 23 ± 9 kg, p = 0.023). Clinical maturation was significantly greater in handgrip group versus control group, both at 4 weeks after intervention (62% vs 23%, p = 0.004) and at 8 weeks (65% vs 27%, p = 0.004). Similarly, the Doppler ultrasonography maturation rates were significantly greater in the HG, both at 4 weeks (HG: 84% vs CG: 47%; p = 0.004) and at 8 weeks (HG: 89% vs CG: 50%; p = 0.002). CONCLUSIONS: The hand grip is a useful and safety training device to improve the arteriovenous fistula maturation. This device results a new therapeutic option for maturation in arteriovenous fistula, particularly in distal arteriovenous fistula. Further studies are required to support these results.
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INTRODUCTION: Arteriovenous fistula (AVF) is the gold standard for vascular access (VA) for end-stage chronic kidney disease (CKD) patients. Post-operative exercises may help to improve maturation. Nevertheless, scarce scientific evidence has been reported about their utility to date. Our objective was to assess the effect of a post-operative isometric exercise programme on native VA maturation in patients with stage 5-5D CKD. METHODS: We performed a 24-month prospective study. After surgery, patients were randomized to the isometric exercise group (EG) or control group (CG). An isometric exercise protocolled programme was performed in the EG. The CG received usual care. Demographic data, muscle strength using a hand-grip (HG) dynamometer, main Doppler ultrasound (DUS) measurements, clinical and DUS maturation and VA complications were assessed at 4 and 8 weeks post-operatively. RESULTS: For 60 sixty patients (30 in the EG), demographic data and HG and DUS measurements at baseline were similar. A significant increase in HG was observed only in the EG at the end of the study (20.7 ± 8.1 versus 25.1 ± 10.3 kg, P = 0.001). The EG obtained the highest clinical maturation at 4 (CG 33.3% versus EG 70%, P = 0.009) and 8 weeks (CG 33.3% versus EG 76.7%, P = 0.002). Similarly, DUS maturation was better in the EG at 4 (CG 40% versus EG 80%, P = 0.003) and 8 weeks (CG 43.3% versus EG 83.3%, P = 0.003) and remained so in the EG for both distal and proximal VA territories for all these periods. CONCLUSIONS: The upper limb isometric exercise protocolled programme improved clinical and DUS maturation in our patients in both the distal and proximal VA territories. Further studies are required to support these results.
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INTRODUCTION: The number of elderly patients undergoing hemodialysis is steadily increasing. The choice and management of vascular access (VA) in these patients are difficult, and the role of postoperative isometric exercises on native VA maturation in the elderly population is not clearly established. OBJECTIVES: To assess the effect of postoperative isometric exercises on native VA maturation in patients older than 75 years with advanced chronic kidney disease. METHODOLOGY: This was a randomized single-center study over a 24-month period. Postoperative isometric exercises were performed in the exercise group (EG), while the control group (CG) received usual care. Demographic data, muscle strength (using handgrip [HG] dynamometer), Doppler ultrasound (DUS), incidence of VA complications, and clinical and DUS maturation were assessed at 4 and 8 weeks. RESULTS: A total of 27 patients were included (EG: 14, CG: 13). The mean age of the patients was 79.9 ± 2.8 years; 74.1% were men, and 59.2% had radiocephalic VA. Demographic data, HG, and DUS measurements were similar at baseline. DUS measurements significantly increased in both groups at the end of the study. A significant increase in HG (19.1 ± 7.8 kg vs. 22.9 ± 9.7 kg, P = 0.001) and the highest clinical (CG vs. EG: 46.2% vs. 78.6%; P = 0.049) and DUS maturation (CG vs. EG: 30.8% vs. 71.4%; P = 0.041) were observed in the EG at 8 weeks. Globally, medical or surgical VA complications were lower in the EG and mainly included significant stenosis (CG vs. EG: 23.1% vs. 7.1%), although no significant differences were observed. CONCLUSIONS: Once a native VA is indicated in elderly patients, postoperative isometric exercise should be considered in order to improve the odds of achieving a mature functional arteriovenous fistula. Further studies are required to support our findings in this population.
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Derivação Arteriovenosa Cirúrgica , Força da Mão , Idoso , Exercício Físico , Feminino , Humanos , Masculino , Diálise Renal , UltrassonografiaRESUMO
Ewing sarcoma is characterized by pathognomonic translocations, most frequently fusing EWSR1 with FLI1. An estimated 30% of Ewing sarcoma tumors also display genetic alterations in STAG2, TP53, or CDKN2A (SPC). Numerous attempts to develop relevant Ewing sarcoma models from primary human cells have been unsuccessful in faithfully recapitulating the phenotypic, transcriptomic, and epigenetic features of Ewing sarcoma. In this study, by engineering the t(11;22)(q24;q12) translocation together with a combination of SPC mutations, we generated a wide collection of immortalized cells (EWIma cells) tolerating EWSR1-FLI1 expression from primary mesenchymal stem cells (MSC) derived from a patient with Ewing sarcoma. Within this model, SPC alterations strongly favored Ewing sarcoma oncogenicity. Xenograft experiments with independent EWIma cells induced tumors and metastases in mice, which displayed bona fide features of Ewing sarcoma. EWIma cells presented balanced but also more complex translocation profiles mimicking chromoplexy, which is frequently observed in Ewing sarcoma and other cancers. Collectively, these results demonstrate that bone marrow-derived MSCs are a source of origin for Ewing sarcoma and also provide original experimental models to investigate Ewing sarcomagenesis. SIGNIFICANCE: These findings demonstrate that Ewing sarcoma can originate from human bone-marrow-derived mesenchymal stem cells and that recurrent mutations support EWSR1-FLI1 translocation-mediated transformation.
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Transformação Celular Neoplásica , Suscetibilidade a Doenças , Células-Tronco Mesenquimais/metabolismo , Sarcoma de Ewing/etiologia , Sarcoma de Ewing/metabolismo , Animais , Biomarcadores , Sistemas CRISPR-Cas , Células Cultivadas , Biologia Computacional/métodos , Modelos Animais de Doenças , Edição de Genes , Perfilação da Expressão Gênica , Rearranjo Gênico , Marcação de Genes , Xenoenxertos , Humanos , Imunofenotipagem , Hibridização in Situ Fluorescente , Células-Tronco Mesenquimais/patologia , Camundongos , Mutação , Sarcoma de Ewing/patologia , Translocação GenéticaRESUMO
BACKGROUND: The epidemiological situation generated by COVID-19 has highlighted the importance of applying non-pharmacological measures in the management of the epidemic. Mass screening of the asymptomatic general population has been established as a priority strategy by carrying out diagnostic tests to detect possible cases, isolate contacts, cut transmission chains and thus limit the spread of the virus. OBJECTIVE: To evaluate the economic impact of mass COVID-19 screenings of an asymptomatic population during the first and second wave of the epidemic in Catalonia, Spain. METHODOLOGY: Cost-Benefit Analysis based on the estimated total costs of mass screening versus health gains and associated health costs avoided. RESULTS: Excluding the value of monetized health, the Benefit-Cost ratio was estimated at 0.45, a low value that would seem to advise against mass screening policies. However, if monetized health is included, the ratio is close to 1.20, reversing the interpretation. In other words, the monetization of health is the critical element that tips the scales in favour of the desirability of screening. Results show that the interventions with the highest return are those that maximize the percentage of positives detected. CONCLUSION: Efficient management of resources for the policy of mass screening in asymptomatic populations can generate high social returns. The positivity rate critically determines its desirability. Likewise, precocity in the detection of cases will cut more transmissions in the chain of contagion and increase the economic return of these interventions. Maximizing the value of resources depends on screening strategies being accompanied by contact-tracing and specific in their focus, targeting, for example, high-risk subpopulations with the highest rate of expected positives.
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COVID-19 , Busca de Comunicante , Análise Custo-Benefício , Humanos , SARS-CoV-2 , Espanha/epidemiologiaRESUMO
Monogenic disorders are often the result of single point mutations in specific genes, leading to the production of non-functional proteins. Different blood disorders such as ß-thalassemia, sickle cell disease, hereditary spherocytosis, Fanconi anemia, and Hemophilia A and B are usually caused by point mutations. Gene editing tools including TALENs, ZFNs, or CRISPR/Cas platforms have been developed to correct mutations responsible for different diseases. However, alternative molecular tools such as triplex-forming oligonucleotides and their derivatives (e.g., peptide nucleic acids), not relying on nuclease activity, have also demonstrated their ability to correct mutations in the DNA. Here, we review the Repair-PolyPurine Reverse Hoogsteen hairpins (PPRHs) technology, which can represent an alternative gene editing tool within this field. Repair-PPRHs are non-modified single-stranded DNA molecules formed by two polypurine mirror repeat sequences linked by a five-thymidine bridge, followed by an extended sequence at one end of the molecule which is homologous to the DNA sequence to be repaired but containing the corrected nucleotide. The two polypurine arms of the PPRH are bound by intramolecular reverse-Hoogsteen bonds between the purines, thus forming a hairpin structure. This hairpin core binds to polypyrimidine tracts located relatively near the target mutation in the dsDNA in a sequence-specific manner by Watson-Crick bonds, thus producing a triplex structure which stimulates recombination. This technology has been successfully employed to repair a collection of mutants of the dhfr and aprt genes within their endogenous loci in mammalian cells and could be suitable for the correction of mutations responsible for blood disorders.
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Considering their current burden and epidemiological projections, nowadays Parkinson's disease and the COVID-19 pandemic are two key health problems. There is evidence of the pathogenic role of neurotropic viruses in neurodegenerative diseases and coronaviruses are neurotropic, with some of them selectively targeting the basal ganglia. Moreover, some authors demonstrated the longevity of these viruses in the affected cells of the nervous system for long periods. Coronavirus was detected in brain autopsies and SARS-CoV-2 has been isolated from the CSF of affected patients. The marked inflammatory response in some particular patients with COVID-19 with a consequent increase of pro-inflammatory cytokines is considered a prognostic factor. Immunologic changes are observed in patients with Parkinson's disease, possibly having a role in its pathogenesis. A dynamic pro-inflammatory state accompanies α-synuclein accumulation and the development and progression of neurodegeneration. Also, some viral infectious diseases might have a role as triggers, generating a cross autoimmune reaction against α-synuclein. In the past Coronaviruses have been related to Parkinson's disease, however, until now the causal role of these viruses is unknown. In this paper, our focus is to assess the potential relationship between SARS-CoV-2 infection and Parkinson's disease.
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Twenty-four individually housed Holstein bulls (456 ± 6.9 kg of body weight and 292 ± 1.4 d of age) were enrolled in a complete randomized experiment involving four dietary treatments to evaluate the potential effect of mash particle size of diets in finishing beef diets on behavior, digestibility, and macro- and microscopic changes of the digestive tract. The four treatments were all ingredients sieved at 2 mm (HM2), all ingredients sieved at 3 mm (HM3), all ingredients, but corn, sieved at 2 mm and corn at 10 mm (HM210), and all ingredients, but corn, sieved a 3 mm and corn at 10 mm (HM310). For the HM210 and HM310 mashes, corn ground at 10 mm was mixed with the remaining concentrate ingredients ground at 2 or 3 mm, respectively. Concentrate (36% corn, 19% barley, 15% corn gluten feed, 8.4% wheat; 14% crude protein, 3.28 Mcal of ME/kg) consumption was recorded daily and straw consumption weekly. To register behavior, animals were filmed for 24 h on a weekly basis. At day 49 of study nutrient digestibility was estimated. Bulls were slaughtered after 56 d of exposure to treatments. Digestive tract and hepatic lesions were recorded, and tissue samples from the digestive tract collected. Geometric mean particle size was 0.61 ± 0.041, 0.76 ± 0.041, 0.62 ± 0.041, 0.73 ± 0.041 mm, and percentage of particles between 0.5 and 1 mm were 68 ± 2.9, 46 ± 1.7, 46 ± 5.0, and 39 ± 3.3 g/100 g for HM2, HM210, HM3, and HM310, respectively. Performance, total tract digestibility, or digestive tract integrity did not differ when ingredients were ground at 2 or 3 mm. Grinding corn with a hammer mill sieve size of 10 mm reduced feed efficiency and decreased total tract apparent dry matter, and organic matter digestibility compared with treatments from which all ingredients were ground at 2 or 3 mm. Straw intake was greatest and starch digestibility was least in the HM210 treatment. Last, only minor differences among treatments in rumen wall color, rumen papillae fusion, and histological conformation were observed. In summary, to improve feed efficiency, grinding corn at 10 mm is not recommended. In the present study, grinding procedure did not have a great effect on behavior and/or digestive tract health; however, under commercial conditions (group housing), grinding procedures that cause small mean particle sizes or particle size heterogeneity may increase the risk to suffer digestive tract lesions.
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INTRODUCTION AND OBJECTIVES: Vascular access is essential to perform an adequate hemodialysis. Needle cannulation in vascular access is usually painful. There is little scientific evidence on the analgesic effect of thermotherapy. The aim of this study was to evaluate the analgesic effect of thermotherapy on vascular access cannulation. METHODS: We performed a 2-week single center prospective study. Demographic data and vascular access location were collected. The main outcome was pain perceived in vascular access cannulation measured by the visual analog scale. We performed two phases of study: phase I was performed with usual cannulation procedure, and in phase II, we applied local thermotherapy for 15 min (hot packs: 60 s, 600 W). Also, main hemodynamic data, local, and vascular access-related complications were recorded. RESULTS: A total of 34 patients were enrolled, with a mean age of 67.3 ± 16.4 years and 49.1 ± 66.3 months on hemodialysis. Main cardiovascular risk factors are hypertension (81.8%) and diabetes mellitus (39.4%). Most common vascular access is left radiocephalic fistula (45.5%). Mean weekly/patient cannulation is 6.03 ± 0.2. Mean visual analog scale is 3.8 ± 2.4. At the end of the study, thermotherapy on the vascular access revealed a significant decrease in visual analog scale (3.9 ± 2.4 vs 2.6 ± 2.0, p = 0.002), without hemodynamic changes pre- and post-intervention, nor changes in analgesic or antihypertensive treatment. One patient had a mild surface erythema. No further complications related to vascular access were observed. CONCLUSION: (1) Thermotherapy on the vascular access reduced the pain caused by needle cannulation in our patients, without complications related to vascular access. (2) We will consider its clinical application in those painful vascular access cannulations at our hemodialysis unit. (3) Further studies are required to assess other potential beneficial effects added to thermotherapy in vascular access cannulation procedure.
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Derivação Arteriovenosa Cirúrgica , Implante de Prótese Vascular , Cateterismo , Hipertermia Induzida , Dor/prevenção & controle , Diálise Renal , Idoso , Idoso de 80 Anos ou mais , Cateterismo/efeitos adversos , Cateterismo/instrumentação , Feminino , Hemodinâmica , Humanos , Hipertermia Induzida/efeitos adversos , Hipertermia Induzida/instrumentação , Masculino , Pessoa de Meia-Idade , Agulhas , Dor/diagnóstico , Dor/etiologia , Medição da Dor , Estudos Prospectivos , Fluxo Sanguíneo Regional , Fatores de Tempo , Resultado do TratamentoRESUMO
OBJECTIVES: To assess the kinetics of procalcitonin (PCT) and C-reactive protein (CRP) in pediatric patients who required extracorporeal membrane oxygenation (ECMO) and to analyze its relationship with morbidity and mortality. PATIENTS AND METHODS: Prospective observational study including pediatric patients who required ECMO. Both PCT and CRP were sequentially drawn before ECMO (P0) and until 72 hours after ECMO. RESULTS: A total of 40 patients were recruited. Two cohorts were established based on the value of the P0 PCT (>10 ng/mL). Comparing the kinetics of PCT and CRP in these cohorts, the described curves were the expected for each clinical situation. The cutoff for P0 PCT to predict multiple organ dysfunction syndrome was 2.55 ng/mL (sensibility 83%, specificity 100%). Both PCT and CRP did not predict risk of neurologic sequelae or mortality in any group. CONCLUSIONS: Procalcitonin does not seem to be modified by ECMO and could be a good biomarker of evolution.
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AIM: To evaluate the effectiveness and safety of ertapenem in patients hospitalized at home. PATIENTS & METHODS: Retrospective analysis of data from Spanish Outpatient Parenteral Antimicrobial Therapy (OPAT) registry. RESULTS: Data from 1428 patients (median age 70 years; 5.4% institutionalized) and 1547 infectious processes (24% self-administration) were analyzed. Clinical cure or improvement was achieved in 93.8% of cases. Rate of related readmissions was 4.2%, of clinically important complications -3.9%, and of adverse drug reactions -3.2%. High comorbidity burden, contagion in nursing home and certain types of infection were associated with worse prognosis. Self-administration was effective and safe, except in case of nursing home-acquired infections. CONCLUSION: Ertapenem OPAT was effective and safe. Caregivers in nursing homes should be better trained in OPAT-related procedures.
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Antibacterianos/administração & dosagem , Infecções Bacterianas/tratamento farmacológico , Ertapenem/administração & dosagem , Serviços Hospitalares de Assistência Domiciliar/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/efeitos adversos , Estudos de Coortes , Ertapenem/efeitos adversos , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Casas de Saúde/estatística & dados numéricos , Pacientes Ambulatoriais/estatística & dados numéricos , Sistema de Registros , Estudos Retrospectivos , Autoadministração/estatística & dados numéricosRESUMO
Polypurine reverse-Hoogsteen (PPRH) oligonucleotides are non-modified DNA molecules composed of two mirror-symmetrical polypurine stretches linked by a five-thymidine loop. They can fold into reverse-Hoogsteen hairpins and bind to their polypyrimidine target sequence by Watson-Crick bonds forming a three-stranded structure. They have been successfully used to knockdown gene expression and to repair single-point mutations in cells. In this work, we provide an in vitro characterization (UV and fluorescence spectroscopy, gel electrophoresis and nuclease assays) of the structure and stability of two repair-PPRH oligonucleotides and of the complexes they form with their single-stranded targets. We show that one PPRH oligonucleotide forms a hairpin, while the other folds, in potassium, into a guanine-quadruplex (G4). However, the hairpin-prone oligonucleotide does not form a triplex with its single-stranded target, while the G4-prone oligonucleotide converts from a G4 into a reverse-Hoogsteen hairpin forming a triplex with its target sequence. Our work proves, in particular, that folding of a PPRH oligonucleotide into a G4 does not necessarily impair sequence-specific DNA recognition by triplex formation. It also illustrates an original example of DNA structural conversion of a G4 into a reverse-Hoogsteen hairpin driven by triplex formation; this kind of conversion might occur at particular loci of genomic DNA.
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DNA/química , Quadruplex G , Oligonucleotídeos/genética , Motivos de Aminoácidos/genética , Sequência de Bases , DNA/genética , Reparo do DNA , Proteínas do Olho/genética , Genoma , Proteínas de Homeodomínio/genética , Proteínas do Tecido Nervoso/genética , Conformação de Ácido Nucleico , Mutação Puntual/genética , Espectrometria de Fluorescência , Proteína Homeobox SIX3RESUMO
Correction of point mutations that lead to aberrant transcripts, often with pathological consequences, has been the focus of considerable research. In this work, repair-PPRHs are shown to be a new powerful tool for gene correction. A repair-PPRH consists of a PolyPurine Reverse Hoogsteen hairpin core bearing an extension sequence at one end, homologous to the DNA strand to be repaired but containing the wild type nucleotide instead of the mutation. Previously, we had corrected a single-point mutation with repair-PPRHs using a mutated version of a dihydrofolate reductase (dhfr) minigene. To further evaluate the utility of these molecules, different repair-PPRHs were designed to correct insertions, deletions, substitutions and a double substitution present in a collection of mutants at the endogenous locus of the dhfr gene, the product of which is the target of the chemotherapeutic agent methotrexate. We also describe an approach to use when the point mutation is far away from the homopyrimidine target domain. This strategy consists in designing Long-Distance- and Short-Distance-Repair-PPRHs where the PPRH core is bound to the repair tail by a five-thymidine linker. Surviving colonies in a DHFR selective medium, lacking glycine and sources of purines and thymidine, were analyzed by DNA sequencing, and by mRNA, protein and enzymatic measurements, confirming that all the dhfr mutants had been corrected. These results show that repair-PPRHs can be effective tools to accomplish a permanent correction of point mutations in the DNA sequence of mutant mammalian cells.
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Sequência de Bases , Reparo do DNA , Sequências Repetidas Invertidas , Mutação Puntual , Deleção de Sequência , Tetra-Hidrofolato Desidrogenase/genética , Animais , Células CHO , Cricetulus , Éxons , Expressão Gênica , Loci Gênicos , Terapia Genética/métodos , Íntrons , Mutagênese Insercional , Oligodesoxirribonucleotídeos/química , Oligodesoxirribonucleotídeos/genética , Tetra-Hidrofolato Desidrogenase/metabolismo , TransfecçãoRESUMO
We studied the ability of polypurine reverse Hoogsteen hairpins (PPRHs) to silence a variety of relevant cancer-related genes in several human cell lines. PPRHs are hairpins formed by two antiparallel polypurine strands bound by intramolecular Hoogsteen bonds linked by a pentathymidine loop. These hairpins are able to bind to their target DNA sequence through Watson-Crick bonds producing specific silencing of gene expression. We designed PPRHs against the following genes: BCL2, TOP1, mTOR, MDM2, and MYC and tested them for mRNA levels, cytotoxicity, and apoptosis in prostate, pancreas, colon, and breast cancer cell lines. Even though all PPRHs were effective, the most remarkable results were obtained with those against BCL2 and mammalian target of rapamycin (mTOR) in decreasing cell survival and mRNA levels and increasing apoptosis in prostate, colon, and pancreatic cancer cells. In the case of TOP1, MDM2, and MYC, their corresponding PPRHs produced a strong effect in decreasing cell viability and mRNA levels and increasing apoptosis in breast cancer cells. Thus, we confirm that the PPRH technology is broadly useful to silence the expression of cancer-related genes as demonstrated using target genes involved in metabolism (DHFR), proliferation (mTOR), DNA topology (TOP1), lifespan and senescence (telomerase), apoptosis (survivin, BCL2), transcription factors (MYC), and proto-oncogenes (MDM2).
Assuntos
Inativação Gênica , Genes Neoplásicos , Sequências Repetidas Invertidas , Poli T/genética , RNA Mensageiro/antagonistas & inibidores , Apoptose/genética , Pareamento de Bases , Linhagem Celular Tumoral , Sobrevivência Celular , DNA Topoisomerases Tipo I/genética , DNA Topoisomerases Tipo I/metabolismo , Feminino , Humanos , Masculino , Poli T/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismoRESUMO
OBJECTIVE: To assess the comprehension among cleaning workers of the hazard pictograms as defined by the Globally Harmonized System (GHS) of the United Nations, concerning the classification, labeling and packaging of substances and mixtures. METHODS: A sample of 118 workers was surveyed on their perception of the GHS hazard pictograms. Comprehensibility was measured by the percentage of correct answers and the degree to which they reflected International Organization for Standardization and American National Standards Institute standards for minimum level of comprehension. The influence of different variables to predict comprehension capacity was assessed using a logistic regression model. RESULTS: Three groups of pictograms could be distinguished which were statistically differentiated by their comprehensibility. Pictograms reflecting "acute toxicity" and "flammable", were described correctly by 94% and 95% of the surveyed population, respectively. For pictograms reflecting "systemic toxicity", "corrosive", "warning", "environment" and "explosive" the frequency of correct answers ranged from 48% to 64%, whereas those for pictograms "oxidizing" and "compressed gas" were interpreted correctly by only 7% of respondents. Prognostic factors for poor comprehension included: not being familiar with the pictograms, not having received training on safe use of chemical products, being an immigrant and being 54 years of age or older. CONCLUSIONS: Only two pictograms exceeded minimum standards for comprehension. Training, a tool proven to be effective to improve the correct interpretation of danger symbols, should be encouraged, especially in those groups with greater comprehension difficulties.
OBJETIVO: Valorar la comprensión de los pictogramas de peligro del Sistema Globalmente Armonizado (SGA) de las Naciones Unidas referente a la clasificación, envasado y etiquetado de sustancias y mezclas químicas en trabajadores del sector de la limpieza. MÉTODOS: Se encuestó a una muestra de 118 trabajadores sobre su percepción de los pictogramas de riesgo químico del SGA. Se valoró la comprensibilidad de los pictogramas mediante el porcentaje de aciertos y su adecuación a los estándares de comprensión mínima de la Organización International de Normalización y del Instituto Nacional Estadounidense de Estándares. Se valoró la influencia de distintas variables en la capacidad de comprensión mediante un modelo de regresión logística. RESULTADOS: Se observaron tres grupos de pictogramas estadísticamente diferenciados según su comprensibilidad: los pictogramas "toxicidad aguda" y "inflamable" fueron descritos correctamente por 94 y 95% de los trabajadores encuestados respectivamente, los pictogramas "toxicidad sistémica", "corrosivo", "atención", "medio ambiente" y "explosivo", presentaron frecuencias de acierto del 48 al 64%, mientras que los pictogramas "comburente" y "gases a presión" fueron correctamente interpretados por un 7% de los encuestados. Los factores pronósticos para una peor comprensión fueron no estar familiarizado con los pictogramas, no haber recibido formación en prevención sobre el uso de productos químicos, ser inmigrante y tener más de 54 años de edad. CONCLUSIONES: Solo dos pictogramas superaron los estándares mínimos de comprensión en la muestra estudiada. La formación, un instrumento que ha probado su eficacia para mejorar la interpretación correcta de los símbolos de peligro, debería fomentarse, especialmente en aquellos colectivos con mayor dificultad de comprensión.
RESUMO
BACKGROUND: Haemodialysis (HD) patients are characterised by muscle wasting, decreased physical function and poor quality of life. The objective was to analyse the effect of an intradialysis NMES training programme in muscular strength, functional capacity and quality of life in our HD patients. MATERIAL: HD patients were assigned to NMES (ESG) or control group (CG) in a 12-week single-centre prospective study. Transversal quadriceps muscular area, maximum length quadriceps strength (MLQS), handgrip, sit-to-stand-to-sit 10 test (STS10), "6-min walking test" (6MWT); EuroQol-5D health-related quality of life (EQ-5D) questionnaire, subjective global assessment (SGA) and NMES symptoms questionnaires (SQ) were completed. RESULTS: Thirty-eight patients (54 % men). Mean age 69.7 years. 32.1 months on HD, 23 ESG and 15 in CG. In contrast with CG, ESG significantly (*p < 0.05) improved MLQS* (10.2 6.7 vs. 13.1 8.1 kg), STS10* (41 18.7 vs. 37.2 23.9 s), 6MWT* (12 %, 280.5 vs. 312.4 m) and EQ-5D score* (52.7 vs. 65.5) at the end of the study. However, lower SQ score* (8.5 vs. 5.8 sympt./patient) in ESG was observed, mainly due to muscular pain* (2.2 vs. 1.2), cramps* (1.6 vs. 1.2), numbness* (1.7 vs. 1.1) or stinging* (1.5 vs. 1.1). In ESG, 44 and 72 % referred better wellness sensation and physical condition in SGA, respectively. CONCLUSIONS: Intradialytic NMES of both quadriceps improved muscular strength, functional capacity and quality of life in our HD patients. With the obtained results, NMES constitutes a novel therapeutic alternative to improve the deteriorated physical condition and quality of life of these patients.