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1.
Leukemia ; 37(9): 1879-1886, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37507425

RESUMO

Dysregulated hyperinflammatory response is key in the pathogenesis in patients with severe COVID-19 leading to acute respiratory distress syndrome and multiorgan failure. Whilst immunosuppression has been proven to be effective, potential biological targets and optimal timing of treatment are still conflicting. We sought to evaluate efficacy and safety of the Janus Kinase 1/2 inhibitor ruxolitinib, employing the previously developed COVID-19 Inflammation Score (CIS) in a prospective multicenter open label phase II trial (NCT04338958). Primary objective was reversal of hyperinflammation (CIS reduction of ≥25% at day 7 in ≥20% of patients). In 184 patients with a CIS of ≥10 (median 12) ruxolitinib was commenced at an initial dose of 10 mg twice daily and applied over a median of 14 days (range, 2-31). On day 7, median CIS declined to 6 (range, 1-13); 71% of patients (CI 64-77%) achieved a ≥25% CIS reduction accompanied by a reduction of markers of inflammation. Median cumulative dose was 272.5 mg/d. Treatment was well tolerated without any grade 3-5 adverse events related to ruxolitinib. Forty-four patients (23.9%) died, all without reported association to study drug. In conclusion, ruxolitinib proved to be safe and effective in a cohort of COVID-19 patients with defined hyperinflammation.


Assuntos
COVID-19 , Inibidores de Janus Quinases , Humanos , Estudos Prospectivos , Nitrilas , Inibidores de Janus Quinases/efeitos adversos , Inflamação/tratamento farmacológico , Resultado do Tratamento , Janus Quinase 1
2.
Med Klin Intensivmed Notfmed ; 116(2): 138-145, 2021 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-33112981

RESUMO

BACKGROUND: Patients with severe COVID-19 develop hyperferritinemic inflammation, a rare sepsis-like immune dysregulation syndrome. METHODS: Stratified treatment decisions in a cross-location telemedical interdisciplinary case conference were assessed in this retrospective cohort study. A standardized treatment algorithm including continuous positive airway pressure and noninvasive ventilation was implemented. A locally developed COVID inflammation score (CIS) defined patients at risk for severe disease. Patients with life-threatening inflammation were offered off-label treatment with the immune modulator ruxolitinib. RESULTS: Between 4 March 2020 and 26 June 2020 COVID-19 patients (n = 196) were treated. Median patient age (70 years) and comorbidity were high in interstudy comparison. Mortality in all patients was 17.3%. However, advance care planning statements and physician directives limited treatment intensity in 50% of the deceased patients. CIS monitoring of ruxolitinib-treated high-risk patients (n = 20) on days 5, 7, and15 resulted in suppression of inflammation by 42% (15-70), 54% (15-77) and 60% (15-80). Here, mortality was 20% (4/20). Adjusted for patients with a maximum care directive including ICU, total mortality was 8.7% (17/196). CONCLUSION: Severe COVID-19 pneumonia with hyperferritinemic inflammation is related to macrophage activation syndrome-like sepsis. An interdisciplinary intensive care teleconference as a quality tool for ICUs is proposed to detect patients with rare sepsis-like syndromes.


Assuntos
COVID-19 , SARS-CoV-2 , Idoso , Cuidados Críticos , Humanos , Inflamação , Estudos Retrospectivos
4.
Eur J Obstet Gynecol Reprod Biol ; 254: 315-320, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33045502

RESUMO

OBJECTIVE: To assess the association between ketonuria and hyperemesis gravidarum (HG) disease severity. STUDY DESIGN: We included pregnant women hospitalised for HG who participated in the Maternal and Offspring outcomes after Treatment of HyperEmesis by Refeeding (MOTHER) trial and women who were eligible, chose not to be randomised and agreed to participate in the observational cohort. Between October 2013 and March 2016, in 19 hospitals in the Netherlands, women hospitalised for HG were approached for study participation. The presence of ketonuria was not required for study entry. Ketonuria was measured at hospital admission with a dipstick, which distinguishes 5 categories: negative and 1+ through 4 + . The outcome measures were multiple measures of HG disease severity at different time points: 1) At hospital admission (study entry): severity of nausea and vomiting, quality of life and weight change compared to pre-pregnancy weight, 2) One week after hospital admission: severity of nausea and vomiting, quality of life and weight change compared to admission, 3) Duration of index hospital admission and readmission for HG at any time point RESULTS: 215 women where included. Ketonuria was not associated with severity of nausea and vomiting, quality of life or weight loss at hospital admission, nor was the degree of ketonuria at admission associated with any of the outcomes 1 week after hospital admission. The degree of ketonuria was also not associated with the number of readmissions. However, women with a higher degree of ketonuria had a statistically significant longer duration of hospital stay (per 1+ ketonuria, difference: 0.27 days, 95 % CI: 0.05 to 0.48). CONCLUSIONS: There was no association between the degree of ketonuria at admission and severity of symptoms, quality of life, maternal weight loss, or number of readmissions, suggesting that ketonuria provides no information about disease severity or disease course. Despite this, women with a higher degree of ketonuria at admission were hospitalised for longer. This could suggest that health care professionals base length of hospital stay on the degree of ketonuria. Based on the lack of association between ketonuria and disease severity, we suggest it has no additional value in the clinical management of HG.


Assuntos
Hiperêmese Gravídica , Cetose , Feminino , Humanos , Hiperêmese Gravídica/terapia , Países Baixos , Gravidez , Qualidade de Vida , Índice de Gravidade de Doença
5.
Leukemia ; 34(7): 1805-1815, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32518419

RESUMO

A subgroup of patients with severe COVID-19 suffers from progression to acute respiratory distress syndrome and multiorgan failure. These patients present with progressive hyperinflammation governed by proinflammatory cytokines. An interdisciplinary COVID-19 work flow was established to detect patients with imminent or full blown hyperinflammation. Using a newly developed COVID-19 Inflammation Score (CIS), patients were prospectively stratified for targeted inhibition of cytokine signalling by the Janus Kinase 1/2 inhibitor ruxolitinib (Rux). Patients were treated with efficacy/toxicity guided step up dosing up to 14 days. Retrospective analysis of CIS reduction and clinical outcome was performed. Out of 105 patients treated between March 30th and April 15th, 2020, 14 patients with a CIS ≥ 10 out of 16 points received Rux over a median of 9 days with a median cumulative dose of 135 mg. A total of 12/14 patients achieved significant reduction of CIS by ≥25% on day 7 with sustained clinical improvement in 11/14 patients without short term red flag warnings of Rux-induced toxicity. Rux treatment for COVID-19 in patients with hyperinflammation is shown to be safe with signals of efficacy in this pilot case series for CRS-intervention to prevent or overcome multiorgan failure. A multicenter phase-II clinical trial has been initiated (NCT04338958).


Assuntos
Anti-Inflamatórios/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Síndrome da Liberação de Citocina/tratamento farmacológico , Janus Quinase 1/antagonistas & inibidores , Janus Quinase 2/antagonistas & inibidores , Pneumonia Viral/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Pirazóis/uso terapêutico , Síndrome Respiratória Aguda Grave/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , COVID-19 , Ensaios Clínicos como Assunto , Infecções por Coronavirus/enzimologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Síndrome da Liberação de Citocina/enzimologia , Síndrome da Liberação de Citocina/imunologia , Síndrome da Liberação de Citocina/virologia , Citocinas/antagonistas & inibidores , Citocinas/genética , Citocinas/imunologia , Esquema de Medicação , Feminino , Regulação da Expressão Gênica , Humanos , Imunidade Inata/efeitos dos fármacos , Inflamação , Janus Quinase 1/genética , Janus Quinase 1/imunologia , Janus Quinase 2/genética , Janus Quinase 2/imunologia , Masculino , Pessoa de Meia-Idade , Nitrilas , Pandemias , Segurança do Paciente , Pneumonia Viral/enzimologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Pirimidinas , Estudos Retrospectivos , SARS-CoV-2 , Síndrome Respiratória Aguda Grave/enzimologia , Síndrome Respiratória Aguda Grave/imunologia , Síndrome Respiratória Aguda Grave/virologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/virologia , Resultado do Tratamento
6.
BJOG ; 124(3): 453-461, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-26969198

RESUMO

OBJECTIVE: To assess the economic consequences of immediate delivery compared with expectant monitoring in women with preterm non-severe hypertensive disorders of pregnancy. DESIGN: A cost-effectiveness analysis alongside a randomised controlled trial (HYPITAT-II). SETTING: Obstetric departments of seven academic hospitals and 44 non-academic hospitals in the Netherlands. POPULATION: Women diagnosed with non-severe hypertensive disorders of pregnancy between 340/7 and 370/7  weeks of gestation, randomly allocated to either immediate delivery or expectant monitoring. METHODS: A trial-based cost-effectiveness analysis was performed from a healthcare perspective until final maternal and neonatal discharge. MAIN OUTCOME MEASURES: Health outcomes were expressed as the prevalence of respiratory distress syndrome, defined as the need for supplemental oxygen for >24 hours combined with radiographic findings typical for respiratory distress syndrome. Costs were estimated from a healthcare perspective until maternal and neonatal discharge. RESULTS: The average costs of immediate delivery (n = 352) were €10 245 versus €9563 for expectant monitoring (n = 351), with an average difference of €682 (95% confidence interval, 95% CI -€618 to €2126). This 7% difference predominantly originated from the neonatal admissions, which were €5672 in the immediate delivery arm and €3929 in the expectant monitoring arm. CONCLUSION: In women with mild hypertensive disorders between 340/7 and 370/7  weeks of gestation, immediate delivery is more costly than expectant monitoring as a result of differences in neonatal admissions. These findings support expectant monitoring, as the clinical outcomes of the trial demonstrated that expectant monitoring reduced respiratory distress syndrome for a slightly increased risk of maternal complications. TWEETABLE ABSTRACT: Expectant management in preterm hypertensive disorders is less costly compared with immediate delivery.


Assuntos
Custos de Cuidados de Saúde/estatística & dados numéricos , Hipertensão Induzida pela Gravidez/terapia , Trabalho de Parto Induzido/economia , Conduta Expectante/economia , Análise Custo-Benefício , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Trabalho de Parto Induzido/métodos , Países Baixos , Gravidez , Resultado da Gravidez , Síndrome do Desconforto Respiratório do Recém-Nascido/epidemiologia , Síndrome do Desconforto Respiratório do Recém-Nascido/etiologia , Conduta Expectante/métodos
7.
Dtsch Med Wochenschr ; 141(S 01): S57-S61, 2016 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-27760451

RESUMO

The 2015 European Guidelines on Pulmonary Hypertension did not cover only pulmonary arterial hypertension (PAH) but also some aspects of pulmonary hypertension (PH) associated with chronic lung disease. The European Guidelines point out that the drugs currently used to treat patients with PAH (prostanoids, endothelin receptor antagonists, phosphodiesterase-5 inhibitors, sGC stimulators) have not been sufficiently investigated in other forms of PH. Therefore, the European Guidelines do not recommend the use of these drugs in patients with chronic lung disease and PH. This recommendation, however, is not always in agreement with medical ethics as physicians feel sometimes inclined to treat other form of PH which may affect quality of life and survival of these patients in a similar manner. To this end, it is crucial to consider the severity of both PH and the underlying lung disease. In June 2016, a Consensus Conference organized by the PH working groups of the German Society of Cardiology (DGK), the German Society of Respiratory Medicine (DGP) and the German Society of Pediatric Cardiology (DGPK) was held in Cologne, Germany, to discuss open and controversial issues surrounding the practical implementation of the European Guidelines. Several working groups were initiated, one of which was dedicated to the diagnosis and treatment of PH in patients with chronic lung disease. The recommendations of this working group are summarized in the present paper.


Assuntos
Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/terapia , Lesão Pulmonar/complicações , Lesão Pulmonar/terapia , Guias de Prática Clínica como Assunto , Pneumologia/normas , Cardiologia/normas , Alemanha , Humanos , Hipertensão Pulmonar/diagnóstico , Lesão Pulmonar/diagnóstico
8.
Vet Rec ; 177(3): 74, 2015 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-26089352

RESUMO

In this study, morbidity in insured Nova Scotia Duck Tolling Retriever (NSDTR) dogs from Sweden was investigated and compared with all other breeds and other retriever breeds. In addition to describing common morbidities in NSDTRs, the hypotheses that NSDTRs are predisposed to lymphoma, immune-mediated rheumatic disease (IMRD) and steroid-responsive meningitis-arteritis (SRMA) were tested. Included in the study were 445,336 dogs; of which, 2890 were NSDTRs that had been covered by veterinary insurance from the Agria Insurance Company (Stockholm, Sweden) at some point during the years 1995-2006. Incidences of various health problems were calculated using the number of veterinary visits as the numerator and the exact time at risk as the denominator. Overall, morbidity was higher in NSDTRs compared with all other breeds, but similar compared with other retriever breeds. The most common causes of veterinary visits in NSDTRs were injuries, gastrointestinal disease and locomotor disorders, with NSDTRs at increased risk of these compared with all other breeds. The incidences for IMRD, SRMA and lymphoma were significantly higher in NSDTRs than in all other dog breeds and all other retriever breeds. The study describes morbidity in NSDTRs, and identifies several disorders to which the breed is predisposed.


Assuntos
Doenças do Cão/epidemiologia , Doenças do Sistema Imunitário/veterinária , Seguro Saúde/estatística & dados numéricos , Animais , Cães , Feminino , Doenças do Sistema Imunitário/epidemiologia , Incidência , Masculino , Estudos Retrospectivos , Especificidade da Espécie , Suécia/epidemiologia
9.
J Hum Nutr Diet ; 28(5): 452-64, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25157608

RESUMO

BACKGROUND: Dairy intake is likely to influence dietary energy density (ED) and nutrient density (ND), which are factors representing aspects of dietary quality. Although evidence suggests dairy intake is unlikely to contribute to obesity, intake tends to decrease over adolescence, potentially as a result of concerns around weight gain. We examined associations between dairy intake, ED and ND, and investigated relationships with obesity in adolescents. METHODS: The present study comprised a cross-sectional study of 1613 14-year-olds in the Western Australian Pregnancy Cohort (Raine) Study. Adolescents completed a 212-item food frequency questionnaire. Nutrient Rich Food index 9.3 (NRF9.3) was used to estimate ND. Age-specific body mass index (BMI) and waist-height cut-offs were used to categorise obesity risk. RESULTS: Mean (SD) dairy intake was: 2.62 (1.51) servings daily; ED was 4.53 (0.83) (food and beverage) and 6.28 (1.33) (food only); ND was 373 (109). Dairy intake was inversely associated with ED and positively associated with ND. The odds of being overweight (as assessed by BMI) increased by 1.24 (95% confidence interval = 1.09-1.42) with each 100-point increase in ND, after adjustment for potential confounders and energy intake. ED measures and dairy intake were inversely associated with obesity after adjustment for confounders; associations became nonsignificant after energy adjustment. CONCLUSIONS: The NRF9.3 was originally designed to assess foods, not diets. Further research in other cohorts to determine whether similar findings exist, or investigations into alternate measures of dietary ND, may prove useful. Our findings may be the result of factors such as an excess consumption of refined but fortified foods. Although higher dairy intakes were associated with higher ND, intakes were not associated with higher obesity risk.


Assuntos
Índice de Massa Corporal , Laticínios , Ingestão de Energia , Comportamento Alimentar , Obesidade/etiologia , Adolescente , Austrália , Estudos Transversais , Dieta , Feminino , Humanos , Masculino , Aumento de Peso
11.
BJOG ; 121(8): 1005-14, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24405687

RESUMO

OBJECTIVE: To assess the effect of red blood cell (RBC) transfusion on quality of life in acutely anaemic women after postpartum haemorrhage. DESIGN: Randomised non-inferiority trial. SETTING: Thirty-seven Dutch university and general hospitals. POPULATION: Women with acute anaemia (haemoglobin 4.8-7.9 g/dl [3.0-4.9 mmol/l] 12-24 hours postpartum) without severe anaemic symptoms or severe comorbidities. METHODS: Women were allocated to RBC transfusion or non-intervention. MAIN OUTCOME MEASURES: Primary outcome was physical fatigue 3 days postpartum (Multidimensional Fatigue Inventory, scale 4-20; 20 represents maximal fatigue). Non-inferiority was demonstrated if the physical fatigue difference between study arms was maximal 1.3. Secondary outcomes were health-related quality of life and physical complications. Health-related quality of life questionnaires were completed at five time-points until 6 weeks postpartum. RESULTS: In all, 521 women were randomised to non-intervention (n = 262) or RBC transfusion (n = 259). Mean physical fatigue score at day 3 postpartum, adjusted for baseline and mode of delivery, was 0.8 lower in the RBC transfusion arm (95% confidence interval: 0.1-1.5, P = 0.02) and at 1 week postpartum was 1.06 lower (95% confidence interval: 0.3-1.8, P = 0.01). A median of two RBC units was transfused in the RBC transfusion arm. In the non-intervention arm, 33 women received RBC transfusion, mainly because of anaemic symptoms. Physical complications were comparable. CONCLUSIONS: Statistically, non-inferiority could not be demonstrated as the confidence interval crossed the non-inferiority boundary. Nevertheless, with only a small difference in physical fatigue and no differences in secondary outcomes, implementation of restrictive management seems clinically justified.


Assuntos
Anemia/terapia , Transfusão de Eritrócitos/normas , Fadiga/terapia , Bem-Estar Materno , Hemorragia Pós-Parto/terapia , Adulto , Anemia/etiologia , Fadiga/etiologia , Feminino , Seguimentos , Hospitais Gerais , Hospitais Universitários , Humanos , Países Baixos , Guias de Prática Clínica como Assunto , Qualidade de Vida , Medição de Risco , Índice de Gravidade de Doença , Resultado do Tratamento
12.
BMJ ; 341: c7087, 2010 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-21177352

RESUMO

OBJECTIVE: To compare the effect of induction of labour with a policy of expectant monitoring for intrauterine growth restriction near term. DESIGN: Multicentre randomised equivalence trial (the Disproportionate Intrauterine Growth Intervention Trial At Term (DIGITAT)). SETTING: Eight academic and 44 non-academic hospitals in the Netherlands between November 2004 and November 2008. PARTICIPANTS: Pregnant women who had a singleton pregnancy beyond 36+0 weeks' gestation with suspected intrauterine growth restriction. INTERVENTIONS: Induction of labour or expectant monitoring. MAIN OUTCOME MEASURES: The primary outcome was a composite measure of adverse neonatal outcome, defined as death before hospital discharge, five minute Apgar score of less than 7, umbilical artery pH of less than 7.05, or admission to the intensive care unit. Operative delivery (vaginal instrumental delivery or caesarean section) was a secondary outcome. Analysis was by intention to treat, with confidence intervals calculated for the differences in percentages or means. RESULTS: 321 pregnant women were randomly allocated to induction and 329 to expectant monitoring. Induction group infants were delivered 10 days earlier (mean difference -9.9 days, 95% CI -11.3 to -8.6) and weighed 130 g less (mean difference -130 g, 95% CI -188 g to -71 g) than babies in the expectant monitoring group. A total of 17 (5.3%) infants in the induction group experienced the composite adverse neonatal outcome, compared with 20 (6.1%) in the expectant monitoring group (difference -0.8%, 95% CI -4.3% to 3.2%). Caesarean sections were performed on 45 (14.0%) mothers in the induction group and 45 (13.7%) in the expectant monitoring group (difference 0.3%, 95% CI -5.0% to 5.6%). CONCLUSIONS: In women with suspected intrauterine growth restriction at term, we found no important differences in adverse outcomes between induction of labour and expectant monitoring. Patients who are keen on non-intervention can safely choose expectant management with intensive maternal and fetal monitoring; however, it is rational to choose induction to prevent possible neonatal morbidity and stillbirth. TRIAL REGISTRATION: International Standard Randomised Controlled Trial number ISRCTN10363217.


Assuntos
Retardo do Crescimento Fetal/terapia , Trabalho de Parto Induzido , Conduta Expectante , Adulto , Feminino , Idade Gestacional , Humanos , Início do Trabalho de Parto , Tempo de Internação , Gravidez , Resultado da Gravidez , Adulto Jovem
13.
Biochimie ; 92(1): 12-20, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19835927

RESUMO

During fast growth, the rrn P1 promoters of Escherichia coli operate at their maximum strength, but below their maximum activity (V(max)), since they are not saturated with RNA polymerase. Since higher concentrations of free RNA polymerase are expected to be found in strains carrying rrn deletions, we have analyzed reported electron micrographs of rrn operons from rrn deletion strains growing at maximal rates (at 37 degrees C) in LB medium [1]. We conclude that, in a strain with four of the seven rrn operons inactivated by partial deletions, transcripts are initiated at rrn P1 promoters 1.6-fold more rapidly than in the wild-type strain and the entirety of the rrn operon is transcribed at a 1.5-fold higher average elongation rate due to shortened pauses in the 16S and 23S regions. Under this condition, traffic congestion occurs in front of a pause site in the 5' leader region of the rrn operon near the beginning of the 16S gene; the congestion extends all the way back to the promoter, impedes promoter clearance and limits the promoter activity to one initiation per 0.56 s. This corresponds to a promoter activity of 107 transcripts/min and is assumed to be close to the V(max) of rrn P1 promoters.


Assuntos
RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/enzimologia , Escherichia coli/genética , Regiões Promotoras Genéticas/genética , RNA Ribossômico/genética , Escherichia coli/metabolismo , Cinética , RNA Bacteriano/biossíntese , RNA Bacteriano/genética , RNA Mensageiro/genética , RNA Ribossômico/biossíntese , RNA Ribossômico/metabolismo , Deleção de Sequência
14.
J Bacteriol ; 191(11): 3740-6, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19329648

RESUMO

The value of the rRNA chain elongation rate in bacteria is an important physiological parameter, as it affects not only the rRNA promoter activity but also the free-RNA polymerase concentration and thereby the transcription of all genes. On average, rRNA chains elongate at a rate of 80 to 90 nucleotides (nt) per s, and the transcription of an entire rrn operon takes about 60 s (at 37 degrees C). Here we have analyzed a reported distribution obtained from electron micrographs of RNA polymerase molecules along rrn operons in E. coli growing at 2.5 doublings per hour (S. Quan, N. Zhang, S. French, and C. L. Squires, J. Bacteriol. 187:1632-1638, 2005). The distribution exhibits two peaks of higher polymerase density centered within the 16S and 23S rRNA genes. An evaluation of this distribution indicates that RNA polymerase transcribes the 5' leader region at speeds up to or greater than 250 nt/s. Once past the leader, transcription slows down to about 65 nt/s within the 16S gene, speeds up in the spacer region between the 16S and 23S genes, slows again to about 65 nt/s in the 23S region, and finally speeds up to a rate greater than 400 nt/s near the end of the operon. We suggest that the slowing of transcript elongation in the 16S and 23S sections is the result of transcriptional pauses, possibly caused by temporary interactions of the RNA polymerase with secondary structures in the nascent rRNA.


Assuntos
Escherichia coli/genética , RNA Bacteriano/genética , RNA Ribossômico/genética , Transcrição Gênica/genética , RNA Polimerases Dirigidas por DNA/genética , RNA Polimerases Dirigidas por DNA/metabolismo , Óperon/genética , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética
15.
Eur Respir J ; 33(4): 804-11, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19129293

RESUMO

Continuous positive airway pressure (CPAP) is an effective treatment for obstructive sleep apnoea syndrome (OSAS) but therapy adherence is often low. The hypothesis that CPAP-adherence and clinical outcomes can be improved by either using an autoadjusting-CPAP (APAP) device or an intensive support was tested. A controlled parallel group study was performed with 100 newly diagnosed OSAS patients, randomised into 4 groups (n = 25 each): standard or intensive support plus either APAP or CPAP. Intensive support included education and monthly home visits for 6 months. Clinical outcome was monitored by polysomnography at CPAP initiation and, after 3 and 9 months, compliance data were downloaded from the CPAP devices. After 9 months, intensively supported patients returned for follow-up in 88 versus 68% in the standard-support-group. Daily usage (mean+/-sem 5.7+/-0.2 for intensive support versus 4.6+/-0.4 h for standard support), percentage of days used (80.4+/-2.8 versus 57.0+/-5.9%) and proportion of individual sleep time (80.6+/-3.2 versus 64.9+/-6.2%) were also higher. There was no significant difference between APAP or CPAP, (daily usage 5.2+/-0.4 versus 5.1+/-0.3 h, percentage of days 67.9+/-5.0 versus 69.2+/-4.9%, proportion of sleep time 72.5+/-5.0% versus 72.1+/-5.2%, for APAP and CPAP) but retention rate was higher with CPAP. In summary, intensive support after continuous positive airway pressure initiation, rather than the application of autoadjusting-continuous positive airway pressure, increased therapy adherence.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas/métodos , Serviços de Assistência Domiciliar , Cooperação do Paciente , Apneia Obstrutiva do Sono/terapia , Análise de Variância , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polissonografia
16.
Biochimie ; 90(3): 493-9, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17999920

RESUMO

We have previously proposed that the rate of ribosome function during balanced growth in E. coli, expressed as the rate of peptide chain elongation, is adjusted by a feedback mechanism: whenever that rate is submaximal (i.e. below 22 amino acid residues polymerized per active ribosome at 37 degrees C), the feedback signal ppGpp is generated by an activation of the ppGpp synthetase expressed from the spoT gene. The accumulation of ppGpp reduces the synthesis of additional ribosomes and thereby reduces the consumption of amino acids which, in turn, allows the remaining ribosomes to function at a higher rate. Here we have described with supporting evidence the proposed feedback loop in greater detail and provided a mathematical analysis which predicts that the SpoT ppGpp synthetase activity should be highest when the ribosomes function at their half-maximal rate. This prediction is consistent with reported observations and is independent of the particular (unknown) mechanism by which the rate of translation controls the ppGpp synthetase activity of SpoT.


Assuntos
Escherichia coli/enzimologia , Retroalimentação Fisiológica/fisiologia , Ribossomos/fisiologia , Aminoácidos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli , Regulação Bacteriana da Expressão Gênica , Nucleotídeos de Guanina/metabolismo , Ligases/metabolismo , Pirofosfatases/metabolismo
18.
Eur Respir J ; 28(4): 691-4, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17012628

RESUMO

Addition of inhaled iloprost to bosentan may have beneficial effects in patients with idiopathic pulmonary arterial hypertension (IPAH). A multicentre, open, randomised, controlled trial was performed to assess the safety and efficacy of inhaled iloprost in patients with IPAH who had already been treated with bosentan. The trial was terminated early after a futility analysis predicted failure with respect to the predetermined sample size. At that time, 40 patients were randomised to receive either bosentan alone (control group) or bosentan plus inhaled iloprost (combination group) for a 12-week period. The primary end-point, change in 6-min walking distance, was not met (mean changes +1 m and -9 m in the control and combination group, respectively). These results may have been skewed by three outliers in the iloprost group who presented with severe clinical worsening. None of the secondary end-points including functional class, peak oxygen uptake, and time to clinical worsening differed significantly between groups. The current study failed to show a positive effect of adding inhaled iloprost to bosentan in idiopathic pulmonary arterial hypertension patients. Further studies involving larger sample sizes and long-term follow-up are needed to determine the efficacy of adding inhaled iloprost to bosentan in patients with idiopathic pulmonary arterial hypertension.


Assuntos
Anti-Hipertensivos/uso terapêutico , Hipertensão Pulmonar/tratamento farmacológico , Iloprosta/uso terapêutico , Sulfonamidas/uso terapêutico , Vasodilatadores/uso terapêutico , Administração por Inalação , Adulto , Idoso , Bosentana , Quimioterapia Combinada , Teste de Esforço , Feminino , Humanos , Iloprosta/administração & dosagem , Iloprosta/efeitos adversos , Masculino , Pessoa de Meia-Idade , Vasodilatadores/administração & dosagem , Vasodilatadores/efeitos adversos
20.
Biochimie ; 85(6): 597-609, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12829377

RESUMO

Growth rate-dependent changes in the cytoplasmic concentration of free functional RNA polymerase, [R(f)], affect the activity of all bacterial genes. Since [R(f)] is not accessible to direct experimental quantitation, it can only be found indirectly from an evaluation of promoter activity data. Here, a theory has been derived to calculate [R(f)] from the concentrations of total RNA polymerase and promoters in a model system with known Michaelis-Menten constants for the polymerase-promoter interactions. The theory takes transcript lengths and elongation rates into account and predicts how [R(f)] changes with varying gene dosages. From experimental data on total concentrations of RNA polymerase and kinetic properties of different classes of promoters, the theory was developed into a mathematical model that reproduces the global transcriptional control in Escherichia coli growing at different rates. The model allows an estimation of the concentrations of free and DNA-bound RNA polymerase, as well as the partitioning of RNA polymerase into mRNA and stable RNA synthesizing fractions. According to this model, [R(f)] is about 0.4 and 1.2 microM at growth rates corresponding to 1.0 and 2.5 doublings/h, respectively. The model accurately reflects a number of further experimental observations and suggests that the free RNA polymerase concentration increases with increasing growth rate.


Assuntos
RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/enzimologia , Escherichia coli/genética , Modelos Genéticos , Transcrição Gênica/genética , DNA Bacteriano/genética , DNA Bacteriano/metabolismo , Regulação Bacteriana da Expressão Gênica , Cinética , Regiões Promotoras Genéticas/genética
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