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1.
Braz. j. biol ; 83: e249424, 2023. graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1345538

RESUMO

Abstract Hypoxia is a prominent feature of head and neck cancer. However, the oxygen element characteristics of proteins and how they adapt to hypoxia microenvironments of head and neck cancer are still unknown. Human genome sequences and proteins expressed data of head and neck cancer were retrieved from pathology atlas of Human Protein Atlas project. Then compared the oxygen and carbon element contents between proteomes of head and neck cancer and normal oral mucosa-squamous epithelial cells, genome locations, pathways, and functional dissection associated with head and neck cancer were also studied. A total of 902 differentially expressed proteins were observed where the average oxygen content is higher than that of the lowly expressed proteins in head and neck cancer proteins. Further, the average oxygen content of the up regulated proteins was 2.54% higher than other. None of their coding genes were distributed on the Y chromosome. The up regulated proteins were enriched in endocytosis, apoptosis and regulation of actin cytoskeleton. The increased oxygen contents of the highly expressed and the up regulated proteins might be caused by frequent activity of cytoskeleton and adapted to the rapid growth and fast division of the head and neck cancer cells. The oxygen usage bias and key proteins may help us to understand the mechanisms behind head and neck cancer in targeted therapy, which lays a foundation for the application of stoichioproteomics in targeted therapy and provides promise for potential treatments for head and neck cancer.


Resumo A hipóxia é uma característica proeminente do câncer de cabeça e pescoço. No entanto, as características do elemento oxigênio das proteínas e como elas se adaptam aos microambientes de hipóxia do câncer de cabeça e pescoço ainda são desconhecidas. Sequências do genoma humano e dados expressos de proteínas de câncer de cabeça e pescoço foram recuperados do atlas de patologia do projeto Human Protein Atlas. Em seguida, comparou o conteúdo do elemento de oxigênio e carbono entre proteomas de câncer de cabeça e pescoço, e células epiteliais escamosas da mucosa oral normal, localizações do genoma, vias e dissecção funcional associada ao câncer de cabeça e pescoço também foram estudadas. Um total de 902 proteínas expressas diferencialmente foi observado onde o conteúdo médio de oxigênio é maior do que as proteínas expressas de forma humilde em proteínas de câncer de cabeça e pescoço. Além disso, o conteúdo médio de oxigênio das proteínas reguladas positivamente foi 2,54% maior do que das outras. Nenhum de seus genes codificadores foi distribuído no cromossomo Y. As proteínas reguladas positivamente foram enriquecidas em endocitose, apoptose e regulação do citoesqueleto de actina. O conteúdo aumentado de oxigênio das proteínas altamente expressas e reguladas pode ser causado pela atividade frequente do citoesqueleto e adaptado ao rápido crescimento e divisão das células cancerosas de cabeça e pescoço. O viés do uso de oxigênio e as proteínas-chave podem nos ajudar a entender os mecanismos por trás do câncer de cabeça e pescoço na terapia direcionada, o que estabelece uma base para a aplicação da estequioproteômica na terapia direcionada e oferece uma promessa para potenciais tratamentos para o câncer de cabeça e pescoço.


Assuntos
Humanos , Neoplasias de Cabeça e Pescoço/genética , Oxigênio , Carbono , Proteoma/genética , Microambiente Tumoral
2.
Front Cell Infect Microbiol ; 12: 870852, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35521220

RESUMO

Babesia bigemina is a tick-borne apicomplexan hemoprotozoan responsible for bovine babesiosis. The current drugs used for bovine babesiosis treatment have several drawbacks, including toxicity, the lack of effectiveness to clear the parasite, and potential to develop resistance. Identifying compounds that target essential and unique parasite metabolic pathways is a rational approach toward finding alternative drug treatments. Based on the genome sequence and transcriptomics analysis, it can be inferred that anaerobic glycolysis is the dominant adenosine triphosphate (ATP) supply for Babesia, and lactate dehydrogenase (LDH) is one of the essential enzymes in this pathway. Furthermore, the Babesia LDH sequence is distinct from its bovine homologue and thus a potential chemotherapeutic target that would result in decreasing the ATP supply to the parasite but not to the host. Gossypol is a known efficient specific inhibitor of LDH in the sensu stricto B. bovis and the sensu lato B. microti, among other related parasites, but no such data are currently available in the sensu stricto B. bigemina parasites. Hereby, we show that the LDH amino acid sequence is highly conserved among sensu stricto but not in sensu lato Babesia spp. A predictive structural analysis of B. bigemina LDH showed the conservation of the key amino acids involved in the binding to gossypol compared to B. bovis. Gossypol has a significant (P < 0.0001) inhibitory effect on the in vitro growth of B. bigemina, with IC50 of 43.97 mM after 72 h of treatment. The maximum IC (IC98) was observed at 60 mM gossypol. However, a significant effect on the viability of cattle PBMC was observed when the cells were cultured with 60 mM (IC98) gossypol compared with DMSO-exposed control cells. Interestingly, B. bigemina cultured at 3% oxygen expresses significantly higher levels of LDH and is more resistant to gossypol than the parasites maintained at ambient conditions containing ~20% oxygen. Altogether, the results suggest the potential of gossypol as an effective drug against B. bigemina infection, but the risk of host toxicity at therapeutic doses should be further evaluated in in vivo studies.


Assuntos
Babesia bovis , Babesia , Babesiose , Doenças dos Bovinos , Gossipol , Trifosfato de Adenosina , Animais , Babesia bovis/genética , Babesiose/tratamento farmacológico , Babesiose/parasitologia , Bovinos , Doenças dos Bovinos/parasitologia , Gossipol/farmacologia , L-Lactato Desidrogenase/farmacologia , Leucócitos Mononucleares , Oxigênio
3.
J Nanobiotechnology ; 20(1): 217, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35524276

RESUMO

Designing new oxygenation nanomaterials by oxygen-generating or oxygen-carrying strategies in hypoxia-associated anti-tumor therapy is a high priority target yet challenge. In this work, we fabricated a nanoplatform involving Fenton-like reaction, Pd@MOF-525@HA, to relieve tumor hypoxia via oxygen-generating strategy for enhanced oxygen-dependent anti-tumor therapy. Thereinto, the porphyrinic MOF-525 can produce singlet oxygen (1O2) via light or ultrasonic irradiation for photodynamic and sonodynamic therapy. Notably, the well-dispersed Pd nanocubes within MOF-525 can convert H2O2 into O2 to mitigate the hypoxic environment for enhanced therapy outcome. Moreover, the two-photon activity and cancer cell specific targeting capability of Pd@MOF-525@HA gave rise to deeper tissue penetration and near-infrared light-induced fluorescence imaging to achieve precise guidance for cancer therapy. This work provides a feasible way in designing new oxygenation nanomaterials to relieve tumor hypoxia for enhanced cancer treatment.


Assuntos
Estruturas Metalorgânicas , Fotoquimioterapia , Linhagem Celular Tumoral , Humanos , Peróxido de Hidrogênio , Hipóxia , Estruturas Metalorgânicas/farmacologia , Oxigênio , Hipóxia Tumoral
4.
Am J Vet Res ; 83(6)2022 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-35524961

RESUMO

OBJECTIVE: To compare ketamine-butorphanol-azaperone-medetomidine (KBAM) to detomidine-etorphine-acepromazine (DEA) for field anesthesia in captive Przewalski horses (Equus przewalskii). ANIMALS: 10 adult Przewalski horses. PROCEDURES: A prospective randomized crossover trial was conducted. Each horse was immobilized once with KBAM (200 mg ketamine, 109.2 mg butorphanol, 36.4 mg azaperone, and 43.6 mg medetomidine) and once with DEA (40 mg detomidine premedication, followed 20 minutes later by 3.9 to 4.4 mg etorphine and 16 to 18 mg acepromazine). Both protocols were administered by IM remote dart injection with a washout period of 6 months between treatments. Selected cardiorespiratory variables and quality of anesthesia were recorded. Antagonists were administered IM (KBAM, 215 mg atipamezole and 50 mg naltrexone; DEA, 4 mg RX821002 and 100 mg naltrexone). RESULTS: All horses were anesthetized and recovered uneventfully. Inductions (DEA, 6.8 min; KBAM, 11.6 min; P = 0.04) and recoveries (DEA, 3.2 min; KBAM, 19.6 min; P < 0.01) were faster with DEA compared with KBAM. Quality scores for induction and recovery did not differ between protocols, but maintenance quality was poorer for DEA (P < 0.01). Clinical concerns during DEA immobilizations included apnea, severe hypoxemia (arterial partial pressure of oxygen < 60 mm Hg), muscle rigidity, and tremors. Horses treated with KBAM were moderately hypoxemic, but arterial partial pressures of oxygen were higher compared with DEA (P < 0.01). CLINICAL RELEVANCE: Captive Przewalski horses are effectively immobilized with KBAM, and this protocol results in superior muscle relaxation and less marked hypoxemia during the maintenance phase, but slower inductions and recoveries, compared with DEA.


Assuntos
Anestesia , Ketamina , Acepromazina/farmacologia , Anestesia/veterinária , Animais , Azaperona/farmacologia , Butorfanol/farmacologia , Etorfina/farmacologia , Frequência Cardíaca , Cavalos , Hipnóticos e Sedativos/farmacologia , Hipóxia/tratamento farmacológico , Hipóxia/veterinária , Imidazóis , Imobilização/métodos , Imobilização/veterinária , Ketamina/farmacologia , Medetomidina/farmacologia , Naltrexona/farmacologia , Oxigênio/farmacologia , Estudos Prospectivos
5.
Am J Vet Res ; 83(6)2022 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-35524965

RESUMO

OBJECTIVE: To determine the minimum alveolar concentration (MAC) of isoflurane in donkeys and characterize recovery from anesthesia. ANIMALS: 7 healthy castrated male adult donkeys. PROCEDURES: Anesthesia was induced with propofol and maintained under mechanical ventilation with 1.3% isoflurane end-tidal concentration (ETiso). The MAC of isoflurane was determined after a 60-minute propofol washout period using the bracketing method. A continuous noxious electrical stimulation was applied to the oral mucosa for 1 minute or until the donkey moved. The ETiso was increased or decreased by 10% depending on the response, and MAC was defined as the average of 2 ETiso values allowing and preventing movement in response to stimulation. Arterial blood gases were measured during anesthesia and the recovery period. Unassisted recovery was timed, and a quality score was assigned from 1 (very poor) to 5 (excellent). RESULTS: The mean dose of propofol required for induction was 3.0 ± 0.6 mg/kg. The MAC of isoflurane was 1.44 ± 0.13%. One donkey was excluded from the study because it was still responsive when stimulated at ETiso of 2.8%. Immediately after extubation, the median (range) partial pressure of oxygen in the arterial blood was 63 (minimum to maximum, 46 to 72) mm Hg and 3 donkeys were hypoxemic (partial pressure of arterial oxygen < 60 mm Hg). The median time to standing was 13 (7 to 38) minutes, while the recovery score was 3 (2 to 5). CLINICAL RELEVANCE: The MAC of isoflurane in donkeys is similar to that reported in other species. Oxygen support should be provided to donkeys during recovery from isoflurane anesthesia to prevent hypoxemia.


Assuntos
Anestesia , Anestésicos Inalatórios , Isoflurano , Propofol , Anestesia/veterinária , Anestésicos Inalatórios/farmacologia , Animais , Equidae , Isoflurano/farmacologia , Masculino , Oxigênio , Alvéolos Pulmonares
6.
Phys Biol ; 19(4)2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35526174

RESUMO

The spot patterns on bananas are a striking case of biological pattern formation and-as a qualitative ripeness indicator-linked to 50 million tons of wasted food per year. Ripening bananas develop these senescent spots as phenolic compounds are enzymatically oxidized and cellular integrity is lost. We characterize the dynamics of the spot expansion and their nucleation rates based on time-lapse movies. Spots nucleate for about 2 days yielding a typical density of 8 spots/cm2. The expansion is initially diffusion controlled and the effective diffusion coefficient decreases with nucleation time from 1.3 to 0.4 mm2d-1. During and after expansion, the browning fronts maintain a steep and constant intensity gradient. We quantitatively reproduce these features by a reaction-diffusion model that considers the local oxygen concentration and browning degree of the peel. All model parameters are based on measurements and front stalling is explained by decreasing oxygen levels in the nucleation sites.


Assuntos
Musa , Apoptose , Frutas/metabolismo , Musa/metabolismo , Oxirredução , Oxigênio/metabolismo
7.
PLoS One ; 17(5): e0267513, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35522648

RESUMO

Adipose tissue plays a central role in energy substrate homeostasis and is a key regulator of lipid flow throughout these processes. As hypoxia affects lipid metabolism in adipose tissue, we aimed to investigate the effects of high-altitude chronic hypoxia on lipid metabolism in the adipose tissue of rats using a lipidomic analysis approach. Visceral adipose tissues from rats housed in a high-altitude hypoxia environment representing 4,300 m with 14.07% oxygen (hypoxia group) and from rats housed in a low-altitude normoxia environment representing 41 m with 20.95% oxygen (normoxia group) for 8 weeks were analyzed using an ultra-performance liquid chromatography-Orbitrap mass spectrometry system. After 8 weeks, the body weight and visceral adipose tissue weight of the hypoxia group were significantly decreased compared to those of the normoxia group (p < 0.05). The area and diameter of visceral adipose cells in the hypoxia group were significantly smaller than those of visceral adipose cells in the normoxia group (p < 0.05). The results of lipidomic analysis showed a total of 21 lipid classes and 819 lipid species. The total lipid concentration of the hypoxia group was lower than that in the normoxia group (p < 0.05). Concentrations of diacylglycerols and triacylglycerols in the hypoxia group were significantly lower than those in the normoxia group (p < 0.05). Using univariate and multivariate analyses, we identified 74 lipids that were significantly altered between the normoxia and hypoxia groups. These results demonstrate that high-altitude chronic hypoxia changes the metabolism of visceral adipose glycerides, which may potentially modulate other metabolic processes.


Assuntos
Doença da Altitude , Tecido Adiposo/metabolismo , Altitude , Animais , Hipóxia/metabolismo , Gordura Intra-Abdominal/metabolismo , Metabolismo dos Lipídeos , Lipidômica , Oxigênio/metabolismo , Ratos , Triglicerídeos/metabolismo
8.
Yonsei Med J ; 63(5): 422-429, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35512744

RESUMO

PURPOSE: We previously developed learning models for predicting the need for intensive care and oxygen among patients with coronavirus disease (COVID-19). Here, we aimed to prospectively validate the accuracy of these models. MATERIALS AND METHODS: Probabilities of the need for intensive care [intensive care unit (ICU) score] and oxygen (oxygen score) were calculated from information provided by hospitalized COVID-19 patients (n=44) via a web-based application. The performance of baseline scores to predict 30-day outcomes was assessed. RESULTS: Among 44 patients, 5 and 15 patients needed intensive care and oxygen, respectively. The area under the curve of ICU score and oxygen score to predict 30-day outcomes were 0.774 [95% confidence interval (CI): 0.614-0.934] and 0.728 (95% CI: 0.559-0.898), respectively. The ICU scores of patients needing intensive care increased daily by 0.71 points (95% CI: 0.20-1.22) after hospitalization and by 0.85 points (95% CI: 0.36-1.35) after symptom onset, which were significantly different from those in individuals not needing intensive care (p=0.002 and <0.001, respectively). Trends in daily oxygen scores overall were not markedly different; however, when the scores were evaluated within <7 days after symptom onset, the patients needing oxygen showed a higher daily increase in oxygen scores [1.81 (95% CI: 0.48-3.14) vs. -0.28 (95% CI: 1.00-0.43), p=0.007]. CONCLUSION: Our machine learning models showed good performance for predicting the outcomes of COVID-19 patients and could thus be useful for patient triage and monitoring.


Assuntos
COVID-19 , Hospitalização , Humanos , Unidades de Terapia Intensiva , Aprendizado de Máquina , Oxigênio , Projetos Piloto , Estudos Prospectivos , Estudos Retrospectivos
9.
Nat Commun ; 13(1): 2474, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513374

RESUMO

The endoperoxides of ß-carotene (ßCar-EPOs) are regarded as main products of the chemical deactivation of 1O2 by ß-carotene, one of the most important antioxidants, following a concerted singlet-singlet reaction. Here we challenge this view by showing that ßCar-EPOs are formed in the absence of 1O2 in a non-concerted triplet-triplet reaction: 3O2 + 3ß-carotene → ßCar-EPOs, in which 3ß-carotene manifests a strong biradical character. Thus, the reactivity of ß-carotene towards oxygen is governed by its excited triplet state. ßCar-EPOs, while being stable in the dark, are photochemically labile, and are a rare example of nonaromatic endoperoxides that release 1O2, again not in a concerted reaction. Their light-induced breakdown triggers an avalanche of free radicals, which accounts for the pro-oxidant activity of ß-carotene and the puzzling swap from its anti- to pro-oxidant features. Furthermore, we show that ßCar-EPOs, and carotenoids in general, weakly sensitize 1O2. These findings underlie the key role of the triplet state in determining the chemical and photophysical features of ß-carotene. They shake up the prevailing models of carotenoid photophysics, the anti-oxidant functioning of ß-carotene, and the role of 1O2 in chemical signaling in biological photosynthetic systems. ßCar-EPOs and their degradation products are not markers of 1O2 and oxidative stress but of the overproduction of extremely hazardous chlorophyll triplets in photosystems. Hence, the chemical signaling of overexcitation of the photosynthetic apparatus is based on a 3chlorophyll-3ß-carotene relay, rather than on extremely short-lived 1O2.


Assuntos
Carotenoides , beta Caroteno , Carotenoides/metabolismo , Clorofila/metabolismo , Oxigênio , Fotossíntese , Espécies Reativas de Oxigênio , beta Caroteno/metabolismo
10.
BMJ Open ; 12(5): e058901, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35501079

RESUMO

INTRODUCTION: The aim of this evaluation is to understand whether introducing stabilisation rooms equipped with pulse oximetry and oxygen systems to frontline health facilities in Ikorodu, Lagos State, alongside healthcare worker (HCW) training improves the quality of care for children with pneumonia aged 0-59 months. We will explore to what extent, how, for whom and in what contexts the intervention works. METHODS AND ANALYSIS: Quasi-experimental time-series impact evaluation with embedded mixed-methods process and economic evaluation. SETTING: seven government primary care facilities, seven private health facilities, two government secondary care facilities. TARGET POPULATION: children aged 0-59 months with clinically diagnosed pneumonia and/or suspected or confirmed COVID-19. INTERVENTION: 'stabilisation rooms' within participating primary care facilities in Ikorodu local government area, designed to allow for short-term oxygen delivery for children with hypoxaemia prior to transfer to hospital, alongside HCW training on integrated management of childhood illness, pulse oximetry and oxygen therapy, immunisation and nutrition. Secondary facilities will also receive training and equipment for oxygen and pulse oximetry to ensure minimum standard of care is available for referred children. PRIMARY OUTCOME: correct management of hypoxaemic pneumonia including administration of oxygen therapy, referral and presentation to hospital. SECONDARY OUTCOME: 14-day pneumonia case fatality rate. Evaluation period: August 2020 to September 2022. ETHICS AND DISSEMINATION: Ethical approval from University of Ibadan, Lagos State and University College London. Ongoing engagement with government and other key stakeholders during the project. Local dissemination events will be held with the State Ministry of Health at the end of the project (December 2022). We will publish the main impact results, process evaluation and economic evaluation results as open-access academic publications in international journals. TRIAL REGISTRATION NUMBER: ACTRN12621001071819; Registered on the Australian and New Zealand Clinical Trials Registry.


Assuntos
COVID-19 , Pneumonia , Austrália , Pré-Escolar , Hospitais , Humanos , Hipóxia/complicações , Lactente , Recém-Nascido , Nigéria , Oximetria , Oxigênio/uso terapêutico , Pneumonia/complicações
11.
BMJ ; 377: e068723, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35508314

RESUMO

OBJECTIVE: To estimate the effect of extracorporeal membrane oxygenation (ECMO) compared with conventional mechanical ventilation on outcomes of patients with covid-19 associated respiratory failure. DESIGN: Observational study. SETTING: 30 countries across five continents, 3 January 2020 to 29 August 2021. PARTICIPANTS: 7345 adults admitted to the intensive care unit with clinically suspected or laboratory confirmed SARS-CoV-2 infection. INTERVENTIONS: ECMO in patients with a partial pressure of arterial oxygen to fraction of inspired oxygen (PaO2/FiO2) ratio <80 mm Hg compared with conventional mechanical ventilation without ECMO. MAIN OUTCOME MEASURE: The primary outcome was hospital mortality within 60 days of admission to the intensive care unit. Adherence adjusted estimates were calculated using marginal structural models with inverse probability weighting, accounting for competing events and for baseline and time varying confounding. RESULTS: 844 of 7345 eligible patients (11.5%) received ECMO at any time point during follow-up. Adherence adjusted mortality was 26.0% (95% confidence interval 24.5% to 27.5%) for a treatment strategy that included ECMO if the PaO2/FiO2 ratio decreased <80 mm Hg compared with 33.2% (31.8% to 34.6%) had patients received conventional treatment without ECMO (risk difference -7.1%, 95% confidence interval -8.2% to -6.1%; risk ratio 0.78, 95% confidence interval 0.75 to 0.82). In secondary analyses, ECMO was most effective in patients aged <65 years and with a PaO2/FiO2 <80 mm Hg or with driving pressures >15 cmH2O during the first 10 days of mechanical ventilation. CONCLUSIONS: ECMO was associated with a reduction in mortality in selected adults with covid-19 associated respiratory failure. Age, severity of hypoxaemia, and duration and intensity of mechanical ventilation were found to be modifiers of treatment effectiveness and should be considered when deciding to initiate ECMO in patients with covid-19.


Assuntos
COVID-19 , Oxigenação por Membrana Extracorpórea , Síndrome do Desconforto Respiratório , Insuficiência Respiratória , Adulto , COVID-19/terapia , Humanos , Oxigênio , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/terapia , SARS-CoV-2
12.
Artigo em Inglês | MEDLINE | ID: mdl-35502293

RESUMO

Background: Chronic obstructive pulmonary disease (COPD) often involves the cardiopulmonary dysfunction that deteriorates health-related quality of life (HRQL) and exercise capacity. Work efficiency (WE) indicates the efficiency of overall oxygen consumption (VO2) during exercise. This study investigated whether different WEs have different effects on pulmonary rehabilitation (PR). Methods: Forty-five patients with stable COPD were scheduled for PR. The PR programs consisted of twice-weekly sessions for three months. These patients were comprehensively evaluated by cardiopulmonary exercise testing and COPD assessment test (CAT) before and after PR. We compared these parameters between patients with a normal versus poor WE. Results: Twenty-one patients had a normal WE and twenty-four patients had a poor WE (<8.6 mL/min/watt). Patients with a poor WE had earlier anaerobic metabolism, a poorer oxygen pulse, lower exercise capacity, more exertional dyspnea, and a poorer HRQL than those with a normal WE. PR improved exercise capacity, HRQL, anaerobic threshold, exertional dyspnea and leg fatigue in patients with either normal or poor WE. However, significant improvement of WE, oxygen pulse, respiratory frequency (Rf) during exercise, chest tightness, activity and sleepiness by CAT were noted only in patients with a poor WE. Among the patients with a poor WE, 29% patients had WE returned to normal after PR. Conclusion: Patients with different WE had different responses to PR. PR improved exercise capacity and HRQL regardless of a normal or poor WE. However, WE, oxygen pulse, Rf during exercise, chest tightness, activity and sleepiness were only improved in patients with a poor WE.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Dispneia/diagnóstico , Dispneia/etiologia , Tolerância ao Exercício/fisiologia , Humanos , Oxigênio , Qualidade de Vida , Sonolência
13.
Braz J Biol ; 84: e250134, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35507960

RESUMO

Research work was designed to investigate the density and diversity of pelagic rotifers in a Lake near Marala Headworks. The physico-chemical parameters of water such as pH, dissolved oxygen, temperature, electrical conductivity, transparency and turbidity were evaluated. Correlation between rotifers and these parameters was also studied. Plankton sampling was done on monthly basis in order to check the population density of rotifers. In total, 18 species of rotifers were identified which belonged to 11 genera. The highest number of rotifers and their diversity was shown by genera namely Brachionus, Keratella, and Filinia. The Brachionus calyciflorus was dominant species in all the samples with mean population density (41%). Analysis of variance of physico-chemical parameters presented that the air and water temperature, electrical conductivity, transparency, dissolved oxygen and oxygen saturation were statistically significant in all the months. While pH was statistically non-significant (p≥0.05. Pearson correlation showed that oxygen and transparency were negatively correlated with rotifers density and diversity. Air and water temperature, concentration of hydrogen ions (pH), electrical conductivity and salinity showed positive relationship with density and diversity of rotifers.


Assuntos
Rotíferos , Animais , Oxigênio , Paquistão , Dinâmica Populacional , Água
14.
Arch Microbiol ; 204(6): 297, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35508818

RESUMO

The depletion of dissolved oxygen in a defined synthetic medium can be measured in real time, using a micro-well plate format, associated with a fluorescent plate reader. This technology is appropriate for investigating the effect of antibiotics on cell kinetics because there is a direct correlation between the latter and the amount of dissolved oxygen in the medium of an assay. In this study, the metabolic activity of the opportunistic human pathogen Pseudomonas aeruginosa PA01 was investigated using the OxoPlate OP96U optical sensor technology. The response of P. aeruginosa to aminoglycoside antibiotics when Ca2+and Mg2+ ions are present in the Evans defined synthetic medium was measured. The results revealed that the effect of antibiotics on P. aeruginosa is influenced by the concentration of divalent cations present in the test medium, although the efficiency of Ca2+ in supressing antibiotic activity was found to be greater than that of Mg2+. By comparison to tobramycin, the effect of amikacin is largely inhibited by the Ca2+and Mg2+concentrations. The study results underscore that the reliability of the observation of growth inhibitors is enhanced by the oxygen consumption measurements. Thus, the OxoPlate OP96U system is proven to be an accurate method to test the effectiveness of antibiotic treatments against P. aeruginosa.


Assuntos
Antibacterianos , Pseudomonas aeruginosa , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Cátions Bivalentes/metabolismo , Cátions Bivalentes/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Oxigênio/metabolismo , Reprodutibilidade dos Testes , Tobramicina/metabolismo , Tobramicina/farmacologia
15.
BMC Health Serv Res ; 22(1): 600, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35509043

RESUMO

INTRODUCTION: Therapeutic oxygen should be administered by competent healthcare providers who possess the required competencies of knowledge, skill, and judgment/abilities to make clinical decisions regarding the administration of oxygen. Therefore, this study aimed to assess the knowledge, attitude, and practice of health professionals towards oxygen therapy. METHODS: A multicenter institutional-based cross-sectional study was conducted among 218 health professionals. The assessment was done with a total of 31 questions. After data cleanup analysis was done with SPSS software. Descriptive, chi-square test, bivariable and multivariable analysis were done accordingly. A p-value of ≤0.05 was considered to have a significant association with the outcome variables. RESULTS: Among 218 participants, most of the participants (92.7%) were in the age range of less than 40 years old. Nurses were the most responding professions followed by physicians and midwifes. From the participants, around 54.6, 54.6, and 65.1% of respondents answered above the means score of knowledge, attitude and practice questions respectively. Getting training (AOR- 4.15, CI- 1.15-14.6), work experiences of less than 4 years (AOR- 2.54, 95%CI- (1.28-5.05), and availability of guidelines (AOR- 11.5, CI- 3.35-39.6) were significantly associated with knowledge level. Also work experience of fewer than 4 years (AOR- 3.41, 95%CI- (1.58-7.35) and presence of periodic maintenance and supply of oxygen therapy devices (AOR- 4.32, 95% CI- (1.44-12.9) were associated with practice level. Similarly, work experiences < 4 years (AOR- 8.6, 95%CI- (2.6-29) and getting training (AOR- 21.4, 95%CI-(2.7- 27.3) has a positive (direct) association with the level of attitude, and poor level of knowledge (AOR- 12.1, 95%CI (3.42-42.9) was contributed for negative attitude. CONCLUSION: This study concluded that 54.6, 54.6, and 65.1% of participants have a good level of knowledge, positive attitude, and good level of practice towards oxygen therapy respectively.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde , Adulto , Estudos Transversais , Etiópia , Hospitais , Humanos , Oxigênio , Inquéritos e Questionários
16.
Washington, D.C.; PAHO; 2022-05-19. (OPS/PHE/IMS/COVID-19/22-0006).
em Francês | PAHO-IRIS | ID: phr-56010

RESUMO

Cette publication vise à fournir un aperçu aux professionnels désireux d’initier un processus d’évaluation, de sélection de technologies et d’achat de systèmes de production d’oxygène par adsorption par inversion de pression (PSA) grâce à la collecte d’informations comparatives d’un point de vue technique, administratif et financier. Le document comporte deux parties: la première est axée sur la description de la technologie et sur les avantages et les inconvénients de son achat par le centre de santé; la seconde est axée sur les aspects clés nécessaires à la mise en œuvre par les professionnels d’une procédure de passation de marché plus efficace.


Assuntos
Oxigênio , Doença Pulmonar Obstrutiva Crônica , Adsorção , Acesso a Medicamentos Essenciais e Tecnologias em Saúde
17.
Water Environ Res ; 94(5): e10718, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35502725

RESUMO

Biochemical oxygen demand (BOD) is one of the most important variables indicating stream pollution with a severe condition of organic loading and maintaining aquatic life in ecosystems. Advanced monitoring techniques such as machine learning (ML) methods have been developed for an accurate, reliable, and cost-effective prediction of BOD. This study investigated the effectiveness of four stand-alone ML algorithms, namely, artificial neural network (ANN), support vector machine (SVM), random forest (RF), and gradient boosting machine (GBM), and six novel hybrid algorithms, namely, RF-SVM, ANN-SVM, GBM-SVM, RF-ANN, GBM-ANN, and RF-GBM, in predicting BOD of the Buriganga river system of Bangladesh. The feature importance analysis of RF algorithm indicated that chemical oxygen demand (COD), total dissolved solids (TDS), conductivity, total solids (TS), suspended solids (SS), and turbidity are the most influential parameters for predicting BOD5 . The significance of this study is the application of the novel hybrid models that resulted in higher prediction success; RF-SVM with the highest R2 value (0.908). The employed novel hybrid ML models can be particularly useful for efficient and systematic data management, water pollution control, and prevention in developing countries such as Bangladesh. PRACTITIONER POINTS: Investigated the efficiency of four stand-alone and six novel hybrid ML models for predicting BOD in a river of Bangladesh. The significance of this study is the application of the six novel hybrid models that resulted in higher prediction success. The best three prediction models were RF-SVM, ANN-SVM, and GBM-SVM with a prediction success of 91%, 89.6%, and 88.8% respectively. ML models indicated COD, conductivity, TDS, TS, SS, and turbidity as the most influential variables for predicting BOD. The novel hybrid models can be useful for developing countries for efficient systematic data management, pollution control, and prevention strategies.


Assuntos
Ecossistema , Rios , Algoritmos , Bangladesh , Aprendizado de Máquina , Oxigênio
18.
Sci Rep ; 12(1): 7446, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35523980

RESUMO

The optimal oxygen concentration is unclear for normothermic machine perfusion (NMP) of livers from donation after circulatory death (DCD). Our purposes were to investigate the effect of air-ventilated NMP on the DCD liver, analyze the underlying mechanism and select the targets to predict liver functional recovery with NMP. NMP was performed using the NMP system with either air ventilation or oxygen ventilation for 2 h in the rat liver following warm ischemia and cold-storage preservation. Proteomics and metabolomics were used to reveal the significant molecular networks. The bioinformation analysis was validated by administering peroxisome proliferator activator receptor-γ (PPARγ) antagonist and agonist via perfusion circuit in the air-ventilated NMP. Results showed that air-ventilated NMP conferred a better functional recovery and a less inflammatory response in the rat DCD liver; integrated proteomics and metabolomics analysis indicated that intrahepatic docosapentaenoic acid downregulation and upregulation of cytochrome P450 2E1 (CYP2E1) expression and activity were associated with DCD liver functional recovery with air-ventilated NMP; PPARγ antagonist worsened liver function under air-oxygenated NMP whereas PPARγ agonist played the opposite role. In conclusion, air-ventilated NMP confers a better liver function from DCD rats through the DAP-PPARγ-CYP2E1 axis; CYP2E1 activity provides a biomarker of liver functional recovery from DCD.


Assuntos
Citocromo P-450 CYP2E1 , Transplante de Fígado , Perfusão , Animais , Fígado , Transplante de Fígado/métodos , Preservação de Órgãos/métodos , Oxigênio , PPAR gama , Perfusão/métodos , Ratos
19.
Crit Care ; 26(1): 124, 2022 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-35524282

RESUMO

BACKGROUND: Some academic organizations recommended that physicians intubate patients with COVID-19 with a relatively lower threshold of oxygen usage particularly in the early phase of pandemic. We aimed to elucidate whether early intubation is associated with decreased in-hospital mortality among patients with novel coronavirus disease 2019 (COVID-19) who required intubation. METHODS: A multicenter, retrospective, observational study was conducted at 66 hospitals in Japan where patients with moderate-to-severe COVID-19 were treated between January and September 2020. Patients who were diagnosed as COVID-19 with a positive reverse-transcription polymerase chain reaction test and intubated during admission were included. Early intubation was defined as intubation conducted in the setting of ≤ 6 L/min of oxygen usage. In-hospital mortality was compared between patients with early and non-early intubation. Inverse probability weighting analyses with propensity scores were performed to adjust patient demographics, comorbidities, hemodynamic status on admission and time at intubation, medications before intubation, severity of COVID-19, and institution characteristics. Subgroup analyses were conducted on the basis of age, severity of hypoxemia at intubation, and days from admission to intubation. RESULTS: Among 412 patients eligible for the study, 110 underwent early intubation. In-hospital mortality was lower in patients with early intubation than those with non-early intubation (18 [16.4%] vs. 88 [29.1%]; odds ratio, 0.48 [95% confidence interval 0.27-0.84]; p = 0.009, and adjusted odds ratio, 0.28 [95% confidence interval 0.19-0.42]; p < 0.001). The beneficial effects of early intubation were observed regardless of age and severity of hypoxemia at time of intubation; however, early intubation was associated with lower in-hospital mortality only among patients who were intubated later than 2 days after admission. CONCLUSIONS: Early intubation in the setting of ≤ 6 L/min of oxygen usage was associated with decreased in-hospital mortality among patients with COVID-19 who required intubation. Trial Registration None.


Assuntos
COVID-19 , Mortalidade Hospitalar , Humanos , Hipóxia , Intubação Intratraqueal , Oxigênio , Estudos Retrospectivos , SARS-CoV-2
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