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1.
Phys Rev Lett ; 129(8): 084501, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36053709

RESUMO

We analyze shape oscillations of sessile water drops with fully mobile contact lines (CL) aboard the International Space Station. The unique microgravity environment enables the study of centimeter-sized droplets with associated inertial-capillary motions. Plane-normal substrate vibrations induce resonance behaviors quantified by frequency scans from which the natural frequencies and mode shapes are identified for nine different hydrophobic surfaces. Experimental observations agree well with, and validate, a recent spectral prediction of mobile CL sessile drop oscillations. The experimental findings help elucidate terrestrial droplet inertial spreading, a poorly understood phenomenon pervasive in many processes.


Assuntos
Vibração , Água , Água/química
2.
Ann Oncol ; 28(8): 1957-1963, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28475678

RESUMO

BACKGROUND: Multiple pilot studies, including one in colorectal cancer patients, suggest that creatine, an amino acid derivative, augments muscle, improves strength, and thereby could palliate the cancer anorexia/weight loss syndrome. PATIENTS AND METHODS: In this randomized, double-blind, placebo-controlled trial, incurable patients with this syndrome were assigned creatine (20 g/day load×5 days followed by 2 g/day orally) versus identical placebo. Patients were weighed once a week for 1 month and then monthly. Patients were also assessed over 1 month for appetite and quality of life (validated questionnaires), fist grip strength, body composition (bioelectrical impedance), and adverse events. The primary endpoint was 10% or greater weight gain from baseline during the first month. RESULTS: Within this combined cohort of 263 evaluable patients (134 received creatine and 129 placebo), only 3 gained ≥10% of their baseline weight by 1 month: two creatine-treated and the other placebo-exposed (P = 1.00). Questionnaire data on appetite, quality of life, and activities of daily living showed no statistically significant differences between groups. Similarly, no statistically significant differences between groups were observed for fist-grip strength or body composition. Rates and severity of adverse events were comparable between groups. Finally, a median survival of 230 and 239 days were observed in the creatine and placebo groups, respectively (P = 0.70). CONCLUSION: Creatine, as prescribed in this trial, had no effect on the cancer anorexia/weight loss syndrome.


Assuntos
Anorexia/tratamento farmacológico , Creatina/uso terapêutico , Neoplasias/complicações , Redução de Peso/efeitos dos fármacos , Idoso , Anorexia/etiologia , Creatina/farmacologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placebos
3.
Ann Oncol ; 27(2): 339-44, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26578722

RESUMO

BACKGROUND: Carboplatin (C) and paclitaxel (P) are standard treatments for carcinoma of unknown primary (CUP). Everolimus, an mTOR inhibitor, exhibits activity in diverse cancer types. We did a phase II trial combining everolimus with CP for CUP. We also evaluated whether a gene expression profiling (GEP) test that predicts tissue of origin (TOO) could identify responsive patients. PATIENTS AND METHODS: A tumor biopsy was required for central confirmation of CUP and GEP. Patients with metastatic, untreated CUP received everolimus (30 mg weekly) with P (200 mg/m(2)) and C (area under the curve 6) every 3 weeks. The primary end point was response rate (RR), with 22% needed for success. The GEP test categorized patients into two groups: those having a TOO where CP is versus is not considered standard therapy. RESULTS: Of 45 assessable patients, the RR was 36% (95% confidence interval 22% to 51%), which met criteria for success. Grade ≥3 toxicities were predominantly hematologic (80%). Adequate tissue for GEP was available in 38 patients and predicted 10 different TOOs. Patients with a TOO where platinum/taxane is a standard (n = 19) tended to have higher RR (53% versus 26%) and significantly longer PFS (6.4 versus 3.5 months) and OS (17.8 versus 8.3 months, P = 0.005), compared with patients (n = 19) with a TOO where platinum/taxane is not standard. CONCLUSIONS: Everolimus combined with CP demonstrated promising antitumor activity and an acceptable side-effect profile. A tumor biomarker identifying TOO may be useful to select CUP patients for specific antitumor regimens. CLINICALTRIALSGOV: NCT00936702.


Assuntos
Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carboplatina/uso terapêutico , Everolimo/uso terapêutico , Neoplasias Primárias Desconhecidas/tratamento farmacológico , Neoplasias Primárias Desconhecidas/genética , Paclitaxel/uso terapêutico , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Primárias Desconhecidas/patologia , Estudos Prospectivos , Resultado do Tratamento
4.
J Appl Microbiol ; 116(2): 447-63, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24127653

RESUMO

AIMS: To determine the magnitude of microbial risks from waterborne viruses and bacteria in Bwaise III in Kampala (Uganda), a typical slum in Sub-Saharan Africa. METHODS AND RESULTS: A quantitative microbial risk assessment (QMRA) was carried out to determine the magnitude of microbial risks from waterborne pathogens through various exposure pathways in Bwaise III in Kampala (Uganda). This was based on the concentration of Escherichia coli O157:H7, Salmonella spp., rotavirus (RV) and human adenoviruses F and G (HAdV) in spring water, tap water, surface water, grey water and contaminated soil samples. The total disease burden was 680 disability-adjusted life years (DALYs) per 1000 persons per year. The highest disease burden contribution was caused by exposure to surface water open drainage channels (39%) followed by exposure to grey water in tertiary drains (24%), storage containers (22%), unprotected springs (8%), contaminated soil (7%) and tap water (0.02%). The highest percentage of the mean estimated infections was caused by E. coli O157:H7 (41%) followed by HAdV (32%), RV (20%) and Salmonella spp. (7%). In addition, the highest infection risk was 1 caused by HAdV in surface water at the slum outlet, while the lowest infection risk was 2.71 × 10(-6) caused by E. coli O157:H7 in tap water. CONCLUSIONS: The results show that the slum environment is polluted, and the disease burden from each of the exposure routes in Bwaise III slum, with the exception of tap water, was much higher than the WHO reference level of tolerable risk of 1 × 10(-6) DALYs per person per year. SIGNIFICANCE AND IMPACT OF THE STUDY: The findings of this study provide guidance to governments, local authorities and nongovernment organizations in making decisions on measures to reduce infection risk and the disease burden by 10(2) to 10(5) depending on the source of exposure to achieve the desired health impacts. The infection risk may be reduced by sustainable management of human excreta and grey water, coupled with risk communication during hygiene awareness campaigns at household and community level. The data also provide a basis to make strategic investments to improve sanitary conditions in urban slums.


Assuntos
Adenovírus Humanos/crescimento & desenvolvimento , Escherichia coli O157/crescimento & desenvolvimento , Rotavirus/crescimento & desenvolvimento , Salmonella/crescimento & desenvolvimento , Microbiologia da Água , Bactérias , Efeitos Psicossociais da Doença , Escherichia coli , Humanos , Áreas de Pobreza , Anos de Vida Ajustados por Qualidade de Vida , Medição de Risco , Saneamento/métodos , Saneamento/normas , Microbiologia do Solo , Uganda , População Urbana , Vírus
5.
Acta Anaesthesiol Scand ; 58(1): 114-22, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24341695

RESUMO

BACKGROUND: Aim of this experimental study was to compare haemodynamic effects and outcome with early administration of amiodarone and adrenaline vs. adrenaline alone in pigs with prolonged ventricular fibrillation (VF). METHODS: After 8 min of untreated VF arrest, bolus doses were administered of adrenaline (0.02 mg/kg) and either amiodarone (5 mg/kg) or saline (n = 8 per group) after randomisation. Cardiopulmonary resuscitation (CPR) was commenced immediately after drug administration, and defibrillation was attempted 2 min later. CPR was resumed for another 2 min after each defibrillation attempt, and the same dose of adrenaline was given every 4th minute during CPR. Haemodynamic monitoring and mechanical ventilation continued for 6 h after return of spontaneous circulation (ROSC), and the pigs were euthanised at 48 h. Researchers were blinded for drug groups throughout the study. RESULTS: There was no difference in rates of ROSC and 48-h survival with amiodarone vs. saline (5/8 vs. 7/8 and 0/8 vs. 3/8, respectively). Diastolic aortic pressure and coronary perfusion pressure were significantly lower with amiodarone during CPR and 1 min after ROSC (P < 0.05). The number of electric shocks required for terminating VF, time to ROSC and adrenaline dose were significantly higher with amiodarone (P < 0.01). The incidence of post-resuscitation tachyarrhythmias tended to be higher in the saline group (P = 0.081). CONCLUSION: Early administration of amiodarone did not improve ROSC or 48-h survival rates, and was associated with worse haemodynamics in this swine model of cardiac arrest.


Assuntos
Amiodarona/uso terapêutico , Antiarrítmicos/uso terapêutico , Reanimação Cardiopulmonar/métodos , Parada Cardíaca/tratamento farmacológico , Animais , Cardioversão Elétrica , Epinefrina/farmacologia , Feminino , Parada Cardíaca/fisiopatologia , Hemodinâmica/fisiologia , Razão de Chances , Respiração Artificial , Ressuscitação , Choque/etiologia , Choque/terapia , Suínos , Vasoconstritores/farmacologia
6.
Ann Oncol ; 24(10): 2548-2554, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23798616

RESUMO

BACKGROUND: Based on preclinical studies, the vascular endothelial pathway is an important mechanism for estrogen receptor resistance. We conducted a phase II study of fulvestrant and bevacizumab in patients with aromatase inhibitor pretreated metastatic breast cancer. PATIENTS AND METHODS: A single-stage phase II study was conducted with these objectives: 6-month progression-free survival (PFS), tumor response, toxic effect, and overall survival. Regimen: 250 mg fulvestrant days 1 and 15 (cycle 1) then day 1 (cycle 2 and beyond) and 10 mg/kg bevacizumab days 1 and 15 of each 4-week cycle. RESULTS: At interim analysis, 20 eligible patients initiated treatment, 11 were progression free and on treatment at 3 months, not meeting the protocol-specified efficacy requirements (at least 12 of 20). Accrual remained open during interim analysis with 36 patients enrolling before final study closure. Among the 33 eligible patients, the median PFS was 6.2 months [95% confidence interval (CI) 3.6-10.1 months]. Of the 18 with measurable disease, 4 (22%) patients (95% CI 6% to 48%) had a confirmed tumor response (1 complete, 3 partial). The most common grade 3/4 adverse events were hypertension 3 (9%) and headache 3 (9%). CONCLUSIONS: The fulvestrant/bevacizumab combination is safe and tolerable; however, it did not meet its statistical end point.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Estradiol/análogos & derivados , Receptores de Estrogênio/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/efeitos adversos , Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Antineoplásicos Hormonais/efeitos adversos , Antineoplásicos Hormonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Bevacizumab , Neoplasias da Mama/mortalidade , Intervalo Livre de Doença , Estradiol/efeitos adversos , Estradiol/uso terapêutico , Feminino , Fulvestranto , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Qualidade de Vida
7.
Acta Anaesthesiol Scand ; 57(5): 646-53, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23316707

RESUMO

BACKGROUND: Neuroprotection from therapeutic hypothermia increases when combined with the anaesthetic gas xenon in animal studies. A clinical feasibility study of the combined treatment has been successfully undertaken in asphyxiated human term newborns. It is unknown whether xenon alone would be sufficient for sedation during hypothermia eliminating or reducing the need for other sedative or analgesic infusions in ventilated sick infants. Minimum alveolar concentration (MAC) of xenon is unknown in any neonatal species. METHODS: Eight newborn pigs were anaesthetised with sevoflurane alone and then sevoflurane plus xenon at two temperatures. Pigs were randomised to start at either 38.5°C or 33.5°C. MAC for sevoflurane was determined using the claw clamp technique at the preset body temperature. For xenon MAC determination, a background of 0.5 MAC sevoflurane was used, and 60% xenon added to the gas mixture. The relationship between sevoflurane and xenon MAC is assumed to be additive. Xenon concentrations were changed in 5% steps until a positive clamp reaction was noted. Pigs' temperature was changed to the second target, and two MAC determinations for sevoflurane and 0.5 MAC sevoflurane plus xenon were repeated. RESULTS: MAC for sevoflurane was 4.1% [95% confidence interval (CI): 3.65-4.50] at 38.5°C and 3.05% (CI: 2.63-3.48) at 33.5°C, a significant reduction. MAC for xenon was 120% at 38.5°C and 116% at 33.5°C, not different. CONCLUSION: In newborn swine sevoflurane, MAC was temperature dependent, while xenon MAC was independent of temperature. There was large individual variability in xenon MAC, from 60% to 120%.


Assuntos
Anestésicos Inalatórios/farmacocinética , Hipotermia Induzida/métodos , Éteres Metílicos/farmacocinética , Alvéolos Pulmonares/efeitos dos fármacos , Xenônio/farmacocinética , Animais , Animais Recém-Nascidos , Sevoflurano , Suínos
8.
Verh K Acad Geneeskd Belg ; 73(1-2): 123-51, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22276399

RESUMO

Malaria is a global tropical disease causing more than 1 million deaths and 300 million clinical cases every year. It is caused by parasites from the genus Plasmodium and is transmitted by Anopheles mosquitoes. Approximately 3 billion people live in malaria-endemic regions and a majority of them are infected. In this review, we discuss the life cycle of the parasite, the complex interactions with the human host and the ensuing immune reactions and complications. The immune system plays a dual role in malaria, by providing life-saving immunity against the parasite, but also by causing often lethal complications in a number of patients. Cytokines, chemokines and proteases are key players in the immunopathological complications, and we propose immunomodulation with dexamethasone as a promising strategy for the therapy of malaria-associated acute respiratory distress syndrome.


Assuntos
Anopheles/parasitologia , Antimaláricos/uso terapêutico , Interações Hospedeiro-Parasita , Insetos Vetores/parasitologia , Malária/tratamento farmacológico , Malária/imunologia , Animais , Humanos , Plasmodium/crescimento & desenvolvimento , Plasmodium/fisiologia
9.
Science ; 208(4444): 557-63, 1980 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-17732829

RESUMO

The project "Energy and Society," sponsored by the Swedish Secretariat for Futures Studies, has studied different indigenous energy sources as alternatives to imported oil in Sweden. One alternative is nuclear energy, antoer is renewable energy. Large uncertainties are associated with both alternatives today. The main characteristics of an energy policy for the rest of the century that does not foreclose either of these options have been identified. Such a policy will have to be based on an understanding of similarities and differences between the alternatives. A nuclear and a solar energy system have been outlined as a basis for an analysis of technical, economic, and institutional issues.

10.
Science ; 219(4583): 355-61, 1983 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-17815302

RESUMO

Technology now being introduced in industry, buildings, and transportation is much more energy-efficient than today's average technology. Changes in production and consumption are tending to decrease the intensity of energy use. By applying available economic technology, it may be possible to reduce energy use in Sweden from the present 1400 petajoules per year to about 900 petajoules per year soon after the turn of the century, even with a 50 percent increase in the consumption of goods and services. Technology now being developed could reduce energy demand even further.

11.
Acta Anaesthesiol Scand ; 52(7): 914-9, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18702753

RESUMO

BACKGROUND: The importance of ventilations after cardiac arrest has been much debated recently and eliminating mouth-to-mouth ventilations for bystanders has been suggested as a means to increase bystander cardiopulmonary resuscitation (CPR). Standard basic life support (S-BLS) is not documented to be superior to continuous chest compressions (CCC). METHODS: Retrospective, observational study of all non-traumatic cardiac arrest patients older than 18 years between May 2003 and December 2006 treated by the community-run emergency medical service (EMS) in Oslo. Outcome for patients receiving S-BLS was compared with patients receiving CCC. All Utstein characteristics were registered for both patient groups as well as for patients not receiving any bystander CPR by reviewing Ambulance run sheets, Utstein forms and hospital records. Method of bystander CPR as well as dispatcher instruction was registered by first-arriving ambulance personnel. RESULTS: Six-hundred ninety-five out of 809 cardiac arrests in our EMS were included in this study. Two-hundred eighty-one (40%) received S-CPR and 145 (21%) received CCC. There were no differences in outcome between the two patient groups, with 35 (13%) discharged with a favourable outcome for the S-BLS group and 15 (10%) in the CCC group (P=0.859). Similarly, there was no difference in survival subgroup analysis of patients presenting with initial ventricular fibrillation/ventricular tachycardia after witnessed arrest, with 32 (29%) and 10 (28%) patients discharged from hospital in the S-BLS and CCC groups, respectively (P=0.972). CONCLUSIONS: Patients receiving CCC from bystanders did not have a worse outcome than patients receiving standard CPR, even with a tendency towards a higher distribution of known negative predictive features.


Assuntos
Reanimação Cardiopulmonar/métodos , Reanimação Cardiopulmonar/estatística & dados numéricos , Serviços Médicos de Emergência/métodos , Parada Cardíaca/terapia , Massagem Cardíaca/métodos , Massagem Cardíaca/estatística & dados numéricos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Noruega , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
12.
Acta Anaesthesiol Scand ; 52(1): 155-7, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17999713

RESUMO

BACKGROUND: The identification of a correctly placed tube during anaesthesia routinely depends on the detection of carbon dioxide (CO2) in the expired air. RESULTS: We describe a previously unreported cause of false-positive prediction in two patients with high initial values of CO2 in expired air after oesophageal intubation. Both patients had received bystander cardiopulmonary resuscitation with mouth-to-mouth ventilation, and the CO2 from the rescuers' expired air was trapped and subsequently detected after oesophageal intubation.


Assuntos
Testes Respiratórios , Capnografia , Dióxido de Carbono/análise , Reanimação Cardiopulmonar , Esôfago , Intubação/métodos , Adulto , Idoso de 80 Anos ou mais , Expiração , Reações Falso-Positivas , Feminino , Humanos , Masculino , Futilidade Médica , Estudos Prospectivos , Estômago , Suicídio
13.
Resuscitation ; 72(3): 364-70, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17141936

RESUMO

BACKGROUND: Recent clinical studies reporting the high frequency of inadequate chest compression depth (<38 mm) during CPR, have prompted the question if adult human chest characteristics render it difficult to attain the recommended compression depth in certain patients. MATERIAL AND METHODS: Using a specially designed monitor/defibrillator equipped with a sternal pad fitted with an accelerometer and a pressure sensor, compression force and depth was measured during CPR in 91 adult out-of-hospital cardiac arrest patients. RESULTS: There was a strong non-linear relationship between the force of compression and depth achieved. Mean applied force for all patients was 30.3+/-8.2 kg and mean absolute compression depth 42+/-8 mm. For 87 of 91 patients 38 mm compression depth was obtained with less than 50 kg. Stiffer chests were compressed more forcefully than softer chests (p<0.001), but softer chests were compressed more deeply than stiffer chests (p=0.001). The force needed to reach 38 mm compression depth (F38) and mean compression force were higher for males than for females: 29.8+/-14.5 kg versus 22.5+/-10.2 kg (p<0.02), and 32.0+/-8.3 kg versus 27.0+/-7.0 kg (p<0.01), respectively. There was no significant variation in F38 or compression depth with age, but a significant 1.5 kg mean decrease in applied force for each 10 years increase in age (p<0.05). Chest stiffness decreased significantly (p<0.0001) with an increasing number of compressions performed. Average residual force during decompression was 1.7+/-1.0 kg, corresponding to an average residual depth of 3+/-2 mm. CONCLUSION: In most out-of-hospital cardiac arrest victims adequate chest compression depth can be achieved by a force<50 kg, indicating that an average sized and fit rescuer should be able to perform effective CPR in most adult patients.


Assuntos
Ambulâncias , Reanimação Cardiopulmonar/instrumentação , Parada Cardíaca/terapia , Massagem Cardíaca/instrumentação , Pacientes Ambulatoriais , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Elasticidade , Inglaterra , Desenho de Equipamento , Feminino , Parada Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Noruega , Pressão , Fatores de Risco , Suécia , Tórax/fisiopatologia , Resultado do Tratamento
14.
Sci Rep ; 7(1): 13835, 2017 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-29062028

RESUMO

Malaria is a global disease associated with considerable mortality and morbidity. An appropriately balanced immune response is crucial in determining the outcome of malarial infection. The glucocorticoid (GC) metabolising enzyme, 11ß-hydroxysteroid dehydrogenase-1 (11ß-HSD1) converts intrinsically inert GCs into active GCs. 11ß-HSD1 shapes endogenous GC action and is immunomodulatory. We investigated the role of 11ß-HSD1 in two mouse models of malaria. 11ß-HSD1 deficiency did not affect survival after malaria infection, but it increased disease severity and parasitemia in mice infected with Plasmodium chabaudi AS. In contrast, 11ß-HSD1 deficiency rather decreased parasitemia in mice infected with the reticulocyte-restricted parasite Plasmodium berghei NK65 1556Cl1. Malaria-induced antibody production and pathology were unaltered by 11ß-HSD1 deficiency though plasma levels of IL-4, IL-6 and TNF-α were slightly affected by 11ß-HSD1 deficiency, dependent on the infecting parasite. These data suggest that 11ß-HSD1 is not crucial for survival of experimental malaria, but alters its progression in a parasite strain-specific manner.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/deficiência , Malária/metabolismo , Parasitemia/metabolismo , Plasmodium chabaudi/metabolismo , Animais , Citocinas/genética , Citocinas/metabolismo , Feminino , Malária/genética , Masculino , Camundongos , Camundongos Mutantes , Parasitemia/genética , Especificidade da Espécie
15.
Resuscitation ; 68(1): 51-9, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16325328

RESUMO

There is a need for robust, effective predictors of the outcome from shock for out-of-hospital cardiac arrest patients. Such technology would enable the emergency responder to provide a therapy tailored to the patient's needs. Here we report our most recent findings while dwelling intentionally on the rationale behind the decisions taken during system development. Specifically, we illustrate the need for sensible data selection, fully cross-validated results and the care necessary when evaluating system performance. We analyze 878 pre-shock ECG traces, all of at least 10 s duration from 110 patients with cardiac arrest of cardiac aetiology. The continuous wavelet transform was applied to preshock segments of ECG trace. Time-frequency markers are extracted from the transform and a linear threshold derived from a training set to provide high sensitivity prediction of successful defibrillation. These systems are then evaluated on a withheld test set. All experiments are cross-validated. When compared to popular Fourier-based techniques our wavelet transform method, COP (Cardioversion Outcome Predictor), provides a 10-20% improvement in performance with values of 66 +/- 4 specificity at 95 +/- 4 sensitivity, 61 +/- 4 specificity at 97 +/- 2 sensitivity and 56 +/- 1 specificity at 98 +/- 2 sensitivity achieved for datasets limited to 3, 6, and 9 shocks per patient, respectively. Thus, the assessment of the wavelet marker was associated with a high specificity value at or above 95% sensitivity in comparison to previously reported methods. Therefore, COP could provide an optimal index for the identification of patients for whom shocking would be futile, and for whom an alternative therapy could be considered.


Assuntos
Cardioversão Elétrica , Serviços Médicos de Emergência , Parada Cardíaca/terapia , Animais , Eletrocardiografia , Análise de Fourier , Parada Cardíaca/diagnóstico , Humanos , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador , Resultado do Tratamento
16.
Resuscitation ; 69(1): 15-22, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16488070

RESUMO

A large proportion of deaths in the Western World are caused by ischaemic heart disease. Among these patients a majority die outside hospital due to sudden cardiac death. The prognosis among these patients is in general, poor. However, a significant proportion are admitted to a hospital ward alive. The proportion of patients who survive the hospital phase of an out of hospital cardiac arrest varies considerably. Several treatment strategies are applicable during the post resuscitation care phase, but the level of evidence is weak for most of them. Four treatments are recommended for selected patients based on relatively good clinical evidence: therapeutic hypothermia, beta-blockers, coronary artery bypass grafting, and an implantable cardioverter defibrillator. The patient's cerebral function might influence implementation of the latter two alternatives. There is some evidence for revascularisation treatment in patients with suspected myocardial infarction. On pathophysiological grounds, an early coronary angiogram is a reasonable alternative. Further randomised clinical trials of other post resuscitation therapies are essential.


Assuntos
Cuidados Críticos/métodos , Ressuscitação/métodos , Humanos
17.
Water Sci Technol ; 54(4): 129-37, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17037178

RESUMO

The observed acclimatisation to biodegradable toxicants in anaerobic cassava wastewater treatment is explained by modelling anaerobic cyanide degradation. A complete degradation pathway is proposed for cyanide. Cyanide degradation is modelled as enzymatic hydrolysis to formate and ammonia. Ammonia is added to the inorganic nitrogen content of the digester while formate is degraded by the hydrogenotrophic methanogens. Cyanide irreversible enzyme inhibition is modelled as an inhibition factor to acetate uptake processes. Cyanide irreversible toxicity is modelled as a decay factor to the acetate degraders. Cyanide as well as added phosphorus buffer solution were considered in the chemical equilibrium calculations of pH. The observed reversible effect after acclimatisation of sludge is modelled by a population shift between two aceticlastic methanogens that have different tolerance to cyanide toxicity. The proposed pathway is added to the IWA Anaerobic Digestion Model no.1 (ADM1). The ADM1 model with the designed extension is validated by an experiment using three lab-scale upflow anaerobic sludge bed reactors which were exposed to different cyanide loadings.


Assuntos
Anaerobiose , Cianetos/metabolismo , Recuperação e Remediação Ambiental , Modelos Teóricos , Poluentes da Água/metabolismo , Cianetos/toxicidade , Hidrólise , Poluentes da Água/toxicidade
18.
Biochim Biophys Acta ; 995(2): 151-9, 1989 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-2930793

RESUMO

A model of multiphasic systems, based on the assumption of zero-order partition of substrates and products into the membranes, is applied to reversible mono-substrate and bi-substrate reactions catalysed by membrane-bound enzymes. Apart from replacement of single-phase kinetic constants by apparent kinetic constants, the derived kinetic expressions are formally identical with those for corresponding single-phase systems. The model confers to the apparent kinetic constants an experimentally verifiable meaning. For full characterization of membrane-kinetic systems, experiments at various concentrations of enzyme-embedding phospholipid are required. Extrapolation to zero phospholipid concentration of each Km app then yields the corresponding true kinetic constant characteristic of the membrane-bound enzyme and also provides a technique for determination of the membrane-partition constants. The procedure implies that the phospholipid content should be assayed for full characterization of membrane-bound enzymes. If, for practical reasons, the assays have to be limited to a single enzyme concentration, correction of the apparent kinetic constants is still possible provided the phospholipid concentration and the partition constants of the reactants are known. The model has permitted prediction of a number of previous observations reflecting the multiphasic nature of the systems. The assumptions, underlying the model, and their implications are examined as well as some commonly used experimental designs for determination of the type of enzymic site.


Assuntos
Enzimas/metabolismo , Proteínas de Membrana/metabolismo , Modelos Biológicos , Sítios de Ligação , Catálise , Cinética , Lipossomos/metabolismo , Matemática , Lipídeos de Membrana/metabolismo , Fosfolipídeos/metabolismo
19.
Biochim Biophys Acta ; 1528(2-3): 61-73, 2001 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-11687291

RESUMO

Glycosylation influences the specific activities of serine proteases including tissue-type plasminogen activator and plasmin which act together in a ternary complex with fibrin. Serine proteases and matrix metalloproteinases (MMPs), including gelatinase B, participate in a protease cascade to remodel the extracellular matrix. In addition to the recognition and targeting functions of carbohydrates and the fact that they confer protease resistance on glycoproteins, oligosaccharides may extend particular protein domains of matrix remodelling enzymes and fine-control their activities within the context of the extracellular matrix. For example, the sialic acids of gelatinase B influence the catalytic activity of this enzyme in a complex with the tissue inhibitor of metalloproteinases-1 (TIMP-1).


Assuntos
Matriz Extracelular/enzimologia , Glicosilação , Metaloproteinases da Matriz/química , Serina Endopeptidases/química , Animais , Ativação Enzimática , Matriz Extracelular/química , Humanos , Metaloproteinase 9 da Matriz/química , Modelos Moleculares , Polissacarídeos/química , Conformação Proteica , Estrutura Terciária de Proteína
20.
Biochim Biophys Acta ; 1425(3): 587-98, 1998 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-9838222

RESUMO

Gelatinase B (matrix metalloproteinase-9, MMP-9) contains three N-glycosylation sites and a Ser/Thr/Pro-rich type V collagen domain with repetitive attachment sites for O-linked sugars. Recombinant mouse gelatinase B was expressed in the yeast Pichia pastoris and the N-linked oligosaccharides of the truncated glycoprotein variants were analysed by in gel enzymatic release followed by mass spectrometry and normal phase HPLC. This technology, despite of the limiting amount of material, allowed the analysis of the formula of N- and O-linked sugars of the different glycoprotein variants. The 112/99- and 88-kDa gelatinase B forms each contained an oligomannose series (Man8GlcNAc2 to Man15GlcNAc2). Analysis of the hydrazine-released sugars showed that the O-linked oligosaccharides contained alpha1-2, alpha1-3 or alpha1-6 linked mannoses. These results were confirmed by lectin blot analysis of intact and glycosidase-treated enzyme variants.


Assuntos
Colagenases/química , Oligossacarídeos/química , Acetaldeído/análogos & derivados , Animais , Cromatografia Líquida de Alta Pressão , Colagenases/biossíntese , Colagenases/genética , Glicosídeo Hidrolases , Hemopexina/química , Metaloproteinase 9 da Matriz , Camundongos , Mutação , Pichia/metabolismo , Polissacarídeos/química , Polissacarídeos/metabolismo , Proteínas Recombinantes/química , Análise de Sequência
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