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1.
Chemosphere ; 266: 129017, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33261842

RESUMO

This work describes a novel application of atmospheric pressure gas chromatography time-of-flight mass spectrometry (APGC-TOF-MS) combined with solid-phase microextraction (SPME) for the simultaneous analysis of hydrocarbons and naphthenic acids (NAs) species in raw and ozone-treated oil sands process water (OSPW). SPME method using polydimethylsiloxane (PDMS)-coated fibers was validated using gas chromatography with flame ionization detector (GC-FID) to ensure the SPME extractions were operated appropriately. The ionization pathways of the hydrocarbon species in OSPW in the APGC source were verified by analyzing a mixture of eight polyaromatic hydrocarbons which were ionized primarily via charge transfer to produce [M+] while NAs in OSPW were found to be ionized through protonation to generate [MH+] in the wet APGC source. SPME/APGC-TOF-MS analysis demonstrated a different composition profile in OSPW #1, with 74.5% of hydrocarbon species, 23.4% of O2-NAs, and 2.1% of the oxidized NA species at extraction pH 2.0 compared with that obtained by UPLC-TOF-MS analysis (36.9% of O2-NAs, 26.8% of O3-NAs, 24.9% of O4-NAs, 9.1% of O5-NAs, 2.3% of O6-NAs). Moreover, the peak areas of the total NAs and the total peak areas of NAs + hydrocarbons measured by SPME/APGC-TOF-MS correlated excellently with the total NA concentration determined by UPLC-TOF-MS (R2 = 0.90) and the concentrations of the total acid-extractable organics determined by SPME/GC-FID (R2 = 0.98), respectively. APGC-TOF-MS integrated with the SPME techniques could extend the range of target compounds and be a promising alternative to evaluate and characterize NAs and hydrocarbon in different water types.


Assuntos
Campos de Petróleo e Gás , Poluentes Químicos da Água , Pressão Atmosférica , Ácidos Carboxílicos/análise , Cromatografia Gasosa-Espectrometria de Massas , Água , Poluentes Químicos da Água/análise
2.
Food Chem ; 336: 127635, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32763734

RESUMO

A one-step, highly-efficiency, and low-cost cold atmospheric pressure plasma (CAPP)-based method for obtaining safe-to-consume beetroot juice (BRJ) with enhanced nutritional quality is presented. Three reaction-discharge systems with different CAPPs were studied to check how the composition and physicochemical properties changed during CAPP treatment of BRJ. To identify reactive species occur in gas phase of applied CAPP for BRJ treatment, optical emission spectrometry was used. Finally, the cytotoxicity of so-obtained BRJ to human epithelial colorectal adenocarcinoma (Caco-2) and human non-malignant intestine microvascular endothelial cells (HIMEC) was assessed. Based on the performed analyses it was found that controlled CAPP treatment of BRJ changes the fraction pattern of elements in addition to increase the content of phenolic compound presents in BRJ. Furthermore, the defined CAPP treatment of BRJ inhibits proliferation of Caco-2 cell lines, exhibiting non-cytotoxic effect for HIMEC non-malignant endothelial cells. As a result, safe-to-consume BRJ of improved nutritional quality was produced.


Assuntos
Beta vulgaris/química , Indústria de Processamento de Alimentos/métodos , Sucos de Frutas e Vegetais , Gases em Plasma , Antioxidantes/química , Pressão Atmosférica , Células CACO-2 , Carboidratos/análise , Células Endoteliais/efeitos dos fármacos , Sucos de Frutas e Vegetais/análise , Sucos de Frutas e Vegetais/toxicidade , Humanos , Metais/análise , Valor Nutritivo , Fenóis/análise , Testes de Toxicidade
3.
Food Chem ; 340: 127926, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32919357

RESUMO

This paper provides a method for the quantification of sterols in different types of calf feedstuffs based on soy, sunflower, hay, calf feed and a mixture of all of them. The free fraction and the total sterolic fraction, after saponification and acidic hydrolysis of the samples, are extracted by solvent and the sterols are identified/quantified by reversed phase HPLC coupled to tandem mass spectrometry by atmospheric pressure chemical ionization. After the recovery evaluation, the method is validated in terms of linearity (coefficient of determination R2), repeatability (coefficient of variation RSD), limit of detection and quantification. In most of the cases, the most representative phytosterol is ß-sitosterol, followed by campesterol or stigmasterol and by other minor sterols such as fucosterol, and Δ-5-avenasterol. In addition, also cholesterol and ergosterol, if present, are evaluated in all the samples. As far as we know, very little information is available on the investigated feeds, which are commonly used on farms. The results of this survey were compared to other studies, if present in literature, showing good agreement. The proposed method resulted to be simple, fast and suitable for application to other sterols, feedstuffs and derived foods. The knowledge of the sterolic content and composition is getting more and more important, both in terms of comprehension of the vegetal biochemistry and as basis for sterolomic studies.


Assuntos
Ração Animal/análise , Fitosteróis/análise , Animais , Pressão Atmosférica , Bovinos , Colesterol/análogos & derivados , Cromatografia Líquida de Alta Pressão/métodos , Ergosterol/análise , Helianthus , Sitosteroides/análise , Soja/química , Estigmasterol/análogos & derivados , Estigmasterol/análise , Espectrometria de Massas em Tandem
4.
Chemosphere ; 263: 127963, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297024

RESUMO

In this work, the performance of the atmospheric pressure chemical ionization (APCI) and photoionization (APPI) was assessed to develop a new selective and sensitive gas chromatography-high resolution mass spectrometry (GC-HRMS) method for the determination of polychlorinated naphthalenes (PCNs) in sediment samples. The capability of both APCI and APPI sources for the ionization of PCNs was investigated, showing the formation of the molecular ion and the [M‒Cl+O]‒ ion in positive and negative ion modes, respectively. Positive ion APCI provided high responses using high corona ion current, while the use of high vapour pressure dopant-solvents, such as toluene in positive mode and diethyl ether in the negative mode, was required to achieve high ionization efficiencies in APPI. The performance of the two API sources in the PCN determination by GC-HRMS were compared and the best results were achieved using the GC-APPI(+)-HRMS (Orbitrap) system. The GC-APPI(+)-HRMS (Orbitrap) method was applied to the characterization of Halowax mixtures and the analysis of marine sediments collected near to the coastal area of Barcelona (NE, Spain), demonstrating a great detection capability with low method limits of detection (0.2-1.6 pg g-1 dry weight), good precision (RSD <15%) and trueness (relative error <13%). Total PCN concentrations ranged from 0.35 to 5.0 ng g-1 dry weight and the presence of related compounds, such as polychlorinated biphenyls (PCBs), was also detected by combining positive and negative ion modes, providing complementary information to better monitor of all PCN congener groups. The results presented here show the feasibility of the GC-APPI-HRMS method for the suitable determination of PCNs.


Assuntos
Pressão Atmosférica , Naftalenos , Cromatografia Gasosa-Espectrometria de Massas , Sedimentos Geológicos , Naftalenos/análise , Espanha
5.
J Vis Exp ; (165)2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-33191935

RESUMO

In recent years, non-thermal atmospheric pressure plasmas have been used extensively for surface treatments, in particular, due to their potential in biological applications. However, the scientific results often suffer from reproducibility problems due to unreliable plasma conditions as well as complex treatment procedures. To address this issue and provide a stable and reproducible plasma source, the COST-Jet reference source was developed. In this work, we propose a detailed protocol to perform reliable and reproducible surface treatments using the COST reference microplasma jet (COST-Jet). Common issues and pitfalls are discussed, as well as the peculiarities of the COST-Jet compared to other devices and its advantageous remote character. A detailed description of both solid and liquid surface treatment is provided. The described methods are versatile and can be adapted for other types of atmospheric pressure plasma devices.


Assuntos
Pressão Atmosférica , Gases em Plasma/química , Eletricidade , Imageamento Tridimensional , Reprodutibilidade dos Testes , Amido/química , Propriedades de Superfície , Água/química
6.
Anticancer Res ; 40(11): 6205-6212, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33109557

RESUMO

BACKGROUND/AIM: Mammary carcinoma (MC) remains one of the leading causes of morbidity and mortality in the female population worldwide. Cold physical plasma at atmospheric pressure (CAP) has an antioncogenic effect on tumor cells, and its anticancer properties may complement or even extend existing treatment options. In the present study, the efficacy of CAP was characterized on an MC in vitro cell culture system. MATERIALS AND METHODS: MC cells (MCF-7, MDA-MB-231) were directly treated with CAP or incubated with CAP-treated cell culture medium. Cell growth, cell mobility and apoptosis were subsequently analyzed. RESULTS: A single treatment of MC cells with CAP and CAP treated medium led to a treatment-time dependent reduction of cell growth. Furthermore, CAP exposure led to a loss of cellular motility and induced apoptosis. CONCLUSION: Due to its anticancer properties, CAP treatment is an innovative and promising physical approach to expand and complement the treatment options for MC. In particular, a combination of CAP application with surgical and/or chemotherapeutic interventions might significantly improve the therapeutic outcomes.


Assuntos
Argônio/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Gases em Plasma/uso terapêutico , Argônio/farmacologia , Pressão Atmosférica , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Cinética , Gases em Plasma/farmacologia
7.
Sci Rep ; 10(1): 18290, 2020 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-33106561

RESUMO

To protect Mars from microbial contamination, research on growth of microorganisms found in spacecraft assembly clean rooms under simulated Martian conditions is required. This study investigated the effects of low atmospheric pressure on the growth of chemoorganotrophic spacecraft bacteria and whether the addition of Mars relevant anaerobic electron acceptors might enhance growth. The 125 bacteria screened here were recovered from actual Mars spacecraft. Growth at 7 hPa, 0 °C, and a CO2-enriched anoxic atmosphere (called low-PTA conditions) was tested on five TSA-based media supplemented with anaerobic electron acceptors. None of the 125 spacecraft bacteria showed active growth under the tested low-PTA conditions and amended media. In contrast, a decrease in viability was observed in most cases. Growth curves of two hypopiezotolerant strains, Serratia liquefaciens and Trichococcus pasteurii, were performed to quantify the effects of the added anaerobic electron acceptors. Slight variations in growth rates were determined for both bacteria. However, the final cell densities were similar for all media tested, indicating no general preference for any specific anaerobic electron acceptor. By demonstrating that a broad diversity of chemoorganotrophic and culturable spacecraft bacteria do not grow under the tested conditions, we conclude that there may be low risk of growth of chemoorganotrophic bacteria typically recovered from Mars spacecraft during planetary protection bioburden screenings.


Assuntos
Carnobacteriaceae/crescimento & desenvolvimento , Meios de Cultura/química , Serratia liquefaciens/crescimento & desenvolvimento , Anaerobiose , Pressão Atmosférica , Elétrons , Meio Ambiente Extraterreno , Marte , Viabilidade Microbiana , Simulação de Ambiente Espacial , Astronave
8.
Diabetes Metab Syndr ; 14(6): 1735-1742, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32919321

RESUMO

BACKGROUND AND AIMS: Meteorological parameters play a major role in the transmission of infectious diseases such as COVID-19. In this study, we aim to analyze the correlation between meteorological parameters and COVID-19 pandemic in the financial capital of India, Mumbai. METHODS: In this research, we collected data from April 27 till July 25, 2020 (90 days). A Spearman rank correlation test along with two-tailed p test and an Artificial Neural Network (ANN) technique have been used to predict the associations of COVID-19 with meteorological parameters. RESULTS: A significant correlation of COVID-19 was found with temperature (Tmin), dew point (DPmax), relative humidity (RHmax, RHavg, RHmin) and surface pressure (Pmax, Pavg, Pmin). The parameters which showed significant correlation were then taken for the modeling and prediction of COVID-19 infections using Artificial Neural Network technique. CONCLUSIONS: It was found that the relative humidity and pressure parameters had the most influencing effect out of all other significant parameters (obtained from Spearman's method) on the active number of COVID-19 cases. The finding in this study might be useful for the public, local authorities, and the Ministry of Health, Govt. of India to combat COVID-19.


Assuntos
/epidemiologia , Conceitos Meteorológicos , Pressão Atmosférica , Humanos , Umidade , Índia/epidemiologia , Redes Neurais de Computação , Temperatura , Vento
9.
PLoS One ; 15(9): e0239194, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32966320

RESUMO

BACKGROUND: Aircrew members are required to attend hypoxia awareness training regularly to strengthen their memory of their personal hypoxia symptoms by undergoing training inside a hypobaric chamber. The aim of this study was to examine the association between hypoxia symptoms experienced during two training sessions that were 4 years apart. METHODS: This was a crossover study to compare hypoxia symptoms and self-reported physiological effects of trapped gas between a previous training session and a current training session in an altitude chamber. The subjects were military crew members who undertook a 25,000-feet refresher training course in 2018. We used a structured questionnaire to obtain the target information before and during hypoxia exposure. Data were analyzed using SPSS software. RESULTS: A total of 341 trainees participated in this survey and completely filled out the questionnaire. Gastrointestinal tract discomfort caused by the expansion of trapped gas was the main physiological reaction during the previous and current training sessions. Frequently reported symptoms were poor concentration (30.5%), impaired cognitive function (20.5%), visual disturbances (16.4%), hot flashes (15.8%), and paresthesia (12.6%) during both exposures. However, the proportions of participants reporting poor concentration (P = 0.378) and visual disturbances (P = 0.594) were not significantly different between the recalled and current training sessions. The five most common symptoms among the subjects with less than 1,000 flight hours were poor concentration (29.8%), visual disturbance (27.3%), impaired cognitive function (14.9%), dizziness/lightheadedness (11.6%), and hot flashes (9.9%), which overlapped substantially with the symptoms reported by other subjects. The occurrence of those five most common symptoms in the group with more than 1,000 flight hours did not significantly differ between the recalled training session and the current training session. CONCLUSIONS: The most common hypoxia symptoms reported were similar between the recalled and current training sessions in an environment with a low oxygen concentration. This finding was also clearly affected by the duration of flight experience. Moreover, GI effects of the expansion of trapped gas were commonly observed at low atmospheric pressure.


Assuntos
Hipóxia , Rememoração Mental , Adulto , Medicina Aeroespacial , Altitude , Pressão Atmosférica , Estudos Cross-Over , Feminino , Humanos , Hipóxia/fisiopatologia , Hipóxia/psicologia , Masculino , Pessoa de Meia-Idade , Militares , Inquéritos e Questionários
10.
Hautarzt ; 71(11): 855-862, 2020 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-32997219

RESUMO

BACKGROUND: Besides acute wounds (through trauma or surgical interventions), chronic wounds comprise a relatively large and heterogeneous group of diseases. These include leg ulcers with venous disease greatly prevailing arterial disease, diabetic foot syndrome, and pressure ulcers. Due to a considerable treatment resistance against such therapies, new and effective, additive treatment options especially for chronic wounds are needed. Wound treatment with cold atmospheric plasma (CAP) constitutes such an innovative option. OBJECTIVES: Current research regarding the efficacy of cold plasma for healing of acute and chronic wounds is summarized. MATERIALS AND METHODS: The literature on CAP applications in wound healing has been screened and reviewed. RESULTS: With CAP, several effects that promote wound healing can be simultaneously applied in one application. On the one hand, CAP exerts a strong and broad antimicrobial activity against biofilm. On the other hand, the plasma cocktail, which consists of reactive nitrogen and oxygen species, UV, and charged particles (electrical current), mediates tissue-stimulating, blood flow-promoting, and anti-inflammatory effects. Marked germ reduction on wounds and accelerated wound healing have already been convincingly demonstrated in controlled clinical studies. CONCLUSIONS: The comprehensive CAP study landscape with structured case report summaries and randomized case-control studies allows the conclusion that CAP is safe, effective, and easy to handle for wound treatment. The utilization of CAP in addition to standard wound treatments is starting to enter routine clinical practice.


Assuntos
Pé Diabético , Úlcera da Perna , Gases em Plasma , Pressão Atmosférica , Pé Diabético/terapia , Humanos , Gases em Plasma/uso terapêutico , Cicatrização
11.
Undersea Hyperb Med ; 47(3): 405-413, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32931666

RESUMO

Objective: Given the high mortality and prolonged duration of mechanical ventilation of COVID-19 patients, we evaluated the safety and efficacy of hyperbaric oxygen for COVID-19 patients with respiratory distress. Methods: This is a single-center clinical trial of COVID-19 patients at NYU Winthrop Hospital from March 31 to April 28, 2020. Patients in this trial received hyperbaric oxygen therapy at 2.0 atmospheres of pressure in monoplace hyperbaric chambers for 90 minutes daily for a maximum of five total treatments. Controls were identified using propensity score matching among COVID-19 patients admitted during the same time period. Using competing-risks survival regression, we analyzed our primary outcome of inpatient mortality and secondary outcome of mechanical ventilation. Results: We treated 20 COVID-19 patients with hyperbaric oxygen. Ages ranged from 30 to 79 years with an oxygen requirement ranging from 2 to 15 liters on hospital days 0 to 14. Of these 20 patients, two (10%) were intubated and died, and none remain hospitalized. Among 60 propensity-matched controls based on age, sex, body mass index, coronary artery disease, troponin, D-dimer, hospital day, and oxygen requirement, 18 (30%) were intubated, 13 (22%) have died, and three (5%) remain hospitalized (with one still requiring mechanical ventilation). Assuming no further deaths among controls, we estimate that the adjusted subdistribution hazard ratios were 0.37 for inpatient mortality (p=0.14) and 0.26 for mechanical ventilation (p=0.046). Conclusion: Though limited by its study design, our results demonstrate the safety of hyperbaric oxygen among COVID-19 patients and strongly suggests the need for a well-designed, multicenter randomized control trial.


Assuntos
Betacoronavirus , Infecções por Coronavirus/terapia , Oxigenação Hiperbárica/métodos , Pneumonia Viral/terapia , Pontuação de Propensão , /terapia , Adulto , Idoso , Pressão Atmosférica , Estudos de Casos e Controles , Infecções por Coronavirus/complicações , Infecções por Coronavirus/mortalidade , Feminino , Humanos , Oxigenação Hiperbárica/efeitos adversos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/complicações , Pneumonia Viral/mortalidade , Respiração Artificial/mortalidade , /mortalidade , Fatores de Risco , Segurança , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
12.
Int J Biometeorol ; 64(11): 1815-1823, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32770403

RESUMO

Many people around the world are impacted by some form of bodily pain. Outside factors, such as weather, are thought to help trigger pain, especially in those who have pain-related conditions. When it comes to human health and comfort, understanding the potential external factors that aide in triggering pain is essential. Identifying such factors makes prevention and treatment of pain more feasible. This study focused on how those who suffer from various pain-related conditions (fibromyalgia, rheumatoid arthritis, osteoarthritis, and general back pain) are impacted by different synoptic weather types (i.e., air masses). Synoptic weather types and emergency department (ED) visits for pain in select central North Carolina counties were collected over a seven-year period to determine a potential relationship. Bootstrapped confidence intervals revealed that moist tropical weather types resulted in the highest number of ED visits for each of the conditions examined, while moist polar weather types often resulted in the fewest. The barometric pressure changes associated with transitional weather types, which are often associated with fronts, did not have any significant relationships with pain.


Assuntos
Serviço Hospitalar de Emergência , Tempo (Meteorologia) , Pressão Atmosférica , Humanos , North Carolina/epidemiologia , Dor
13.
Int J Biometeorol ; 64(12): 2119-2125, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32829457

RESUMO

Benign paroxysmal positional vertigo (BPPV) is one of the most common vestibular disorders. An investigation into the factors related to BPPV could contribute to its prevention and appropriate management. We investigated the association between climatic factors and incidence of BPPV in this study. A total of 365 patients who were diagnosed with idiopathic BPPV in the emergency room of our hospital in 2015 were included. The number of patients diagnosed with BPPV per week was calculated (every week). Climatic factors, including daily average humidity, temperature, atmospheric pressure, cloud amount, sunshine amount, and daylight time, were documented daily. The weekly mean climatic value in each week was calculated. Simple correlation analysis and multivariate regression analyses were performed to identify climatic factors associated with the number of patients diagnosed with BPPV. Simple correlation analysis revealed a significant association between the humidity (r = 0.276, p = 0.048), temperature (r = 0.275, p = 0.049), and cloud amount (r = 0.293, p = 0.035) and the number of BPPV patients diagnosed per week. Multivariate regression analysis revealed that only the cloud amount was a statistically significant factor associated with the number of BPPV patients diagnosed every week. A significant positive association was discovered between the cloud amount and BPPV incidence. Cloud amount can therefore have an association with the incidence of BPPV.


Assuntos
Pressão Atmosférica , Vertigem Posicional Paroxística Benigna , Vertigem Posicional Paroxística Benigna/epidemiologia , Humanos , Incidência , Análise Multivariada , Análise de Regressão
14.
J Chromatogr A ; 1628: 461462, 2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32822992

RESUMO

Despite the extensive use of electrospray ionization (ESI) for the quantification of neuropeptides by liquid chromatography-tandem mass spectrometry (LC-MS/MS), poor ionization and transmission efficiency are described for this ionization interface. A new atmospheric pressure ionization source, named UniSpray, was recently developed and commercialized. In this study, the LC-MS performance of this new ionization interface is evaluated and compared with ESI for the quantification of seven neuropeptides. Besides comparison of signal intensities and charge state distributions, also signal-to-noise (S/N) ratios and accuracy and precision were assessed. Additionally, matrix effects of human precipitated plasma and rat microdialysate were evaluated as well as the effect of three supercharging agents on the ionization of the seven neuropeptides. UniSpray ionization resulted in signal intensities four to eight times higher at the optimal capillary/impactor voltage for all seven neuropeptides. S/N values at the other hand only increased by not more than a twofold when the UniSpray source was used. Moreover, UniSpray ionization resulted in a shift towards lower charge states for some neuropeptides. Evaluation of the matrix effects by a post-column infusion set-up resulted in different infusion profiles between ESI and UniSpray. The charge state distributions of the neuropeptides obtained with UniSpray are highly comparable with ESI. Finally, the effect of the supercharging agents on the ionization of the neuropeptides tends to be peptide-dependent with both ionization sources.


Assuntos
Neuropeptídeos/química , Espectrometria de Massas em Tandem , Sequência de Aminoácidos , Animais , Pressão Atmosférica , Cromatografia Líquida , Humanos , Interações Hidrofóbicas e Hidrofílicas , Peso Molecular , Ratos , Processamento de Sinais Assistido por Computador , Razão Sinal-Ruído
15.
J Glaucoma ; 29(9): 756-760, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32618804

RESUMO

PRéCIS:: Intraocular pressure (IOP) measurement differences with Goldmann applanation tonometry (GAT) and dynamic contour tonometry (DCT) are affected by atmospheric pressure inside a hyperbaric chamber. PURPOSE: To compare IOP measurements obtained with GAT and DCT in 22 normal individuals at different atmospheric pressures simulated in a hyperbaric chamber. METHODS: The IOP of both eyes of 22 healthy volunteers was measured using GAT and DCT at 4 different atmospheric pressure levels.Starting at 1 Queretaro atmospheric pressure (QATM), the IOP was measured with GAT and DCT. The atmospheric pressure was then increased to 1.1 QATM (equivalent to 1032 m above sea level), 1.2 QATM (equivalent to 315 m above sea level), and 1.25 QATM (equivalent to sea level), starting 5 minutes after reaching each level. The limits of agreement between various measurements with each tonometer were calculated using the Bland-Altman plots. RESULTS: The first 4 subjects were used to measure feasibility, consistency, variability, and the time needed for IOP to return to baseline after each atmospheric pressure increase.For the entire 44 eyes, the mean GAT IOP at 1 QATM was 12.23 mm Hg (range, 8 to 20 mm Hg; SD, 2.84) and mean DCT was 16.36 (range, 12.1 to 25.3; SD, 2.84), with a mean 4.14 mm Hg difference (range, -0.1 to 7.5 mm Hg; SD, 1.62; P<0.001).Using the second measurements of the first 4 subjects and those after 5 minutes of adaptation for the rest of the group at 1.1 QATM, mean GAT IOP was 11.05±2.68 mm Hg and mean DCT IOP was 15.60±3.02 mm Hg, for a mean difference between instruments of 4.56±1.81 mm Hg (P<0.001).At 1.2 QATM, mean GAT IOP was 11.14±2.53 mm Hg and mean DCT IOP was 15.39±2.91 mm Hg. The difference between instruments was 4.25±2.12 mm Hg (P<0.001).At 1.25 QATM, the mean GAT IOP was 12.39±3.11 mm Hg and mean DCT IOP was 14.91±2.73 mm Hg. The difference between instruments after 5 minutes of adaptation was 2.53±1.62 mm Hg (P<0.001).Generalized estimating equations for performing linear regression multivariable analysis using atmospheric pressure, expressed as altitude, and age as covariates, shows that the difference between GAT and DCT increases by 1 mm Hg per 673 m of increase of altitude above sea level. Age was not a significant predictor. CONCLUSIONS: Acute changes in atmospheric pressure induce changes in IOP measurements for both GAT and DCT and in different directions. Despite the limitation of sample size, it may be postulated that the difference of IOP measurements between the 2 tonometers increases with lower atmospheric pressures.


Assuntos
Pressão Atmosférica , Oxigenação Hiperbárica/efeitos adversos , Pressão Intraocular/fisiologia , Tonometria Ocular/instrumentação , Adulto , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Reprodutibilidade dos Testes
16.
Cuad. Hosp. Clín ; 61(1): [12], jul. 2020. ilus.
Artigo em Espanhol | LILACS, LIBOCS | ID: biblio-1118900

RESUMO

INTRODUCCIÓN: la presión barométrica determina la presión parcial de los gases tanto en el medio ambiente como a nivel alveolar pulmonar, por lo que, para una determinada presión barométrica, la presión de oxígeno y dióxido de carbono es distinta. OBJETIVO: el objetivo del presente estudio es caracterizar los valores de gasometría arterial en residentes adultos sanos a muy alta altitud en la ciudad de El Alto. METODOLOGÍA: Estudio serie de casos, realizado durante la gestión 2019 en 22 (73%) mujeres y 8 varones (27%), con una media de edad de 36.07 años. El estudio contó con la aprobación del Comité de Ética Hospitalario. RESULTADOS: a 4150 metros sobre el nivel del mar, el pH tiende hacia la alcalosis (7.43) así como la PaO2 es menor (58.69mmHg), el valor de PaCO2 (26.14mmHg) es menor correspondiente a una ciudad con mayor altitud, el valor de bicarbonato sérico (20.14mmol/L) se encuentra disminuido en compensación a la disminución de la PaCO2 y el valor de la SatO2% (91.7%) es menor al reportado a nivel del mar. Hay que destacar que el índice PaO2/FiO2 no concuerda con el cálculo realizado según la fórmula propuesta dentro de la definición de los Criterios de Berlín. Se evidencia también que, en la muestra, si bien la correlación entre la PaO2 y la SatO2% resulta como alta, no resulta perfectamente lineal. CONCLUSIÓN: resulta imperativo precisar las características propias a la fisiología correspondientes a cada altitud, buscando aplicar parámetros propios como los de la gasometría arterial para el tratamiento de las enfermedades prevalentes en cada región, así como desarrollar investigaciones específicas a gran altura, ensayar posibilidades y documentarlas.


INTRODUCTION: barometric pressure determines the partial pressure of gases both in the environment and at the pulmonary alveolar level, so for a given barometric pressure, the pressure of oxygen and carbon dioxide is different. The objective of this paper is to characterize arterial blood gas values in healthy adult residents at very high altitude in the city of El Alto. METHODOLOGY: case series study, carried out during 2019; 22 volunteers (73%) women and 8 men (27%), mean age 36.07 years are included. The study was approved by the Hospital Bioethics Committee. RESULTS: at 4150 meter above sea level, pH tends towards alkalosis (7.43) as well as PaO2 is lower (58.69mmHg), the value of PaCO2 (26.14mmHg) is lower corresponding to a city with higher altitude, the value of serum bicarbonate (20.14mmol/L) is lower in compensation at the decrease in PaCO2 and the value of SatO2% (91.7%) is lower than that reported at sea level. The PaO2/FiO2 index does not match the calculation made according to the proposed formula within the definition of the Berlin Criteria. It is also evident that, although the correlation between PaO2 and SatO2% is high, it is not perfectly linear. CONCLUSION: it is imperative to precise the characteristics corresponding to the physiology corresponding to each altitude, looking forward to apply these parameters, such as those of arterial blood gas, in the treatment of prevalent diseases for each region, and so as develop specific studies at high altitude, also testing and reporting them.


Assuntos
Masculino , Feminino , Adulto , Pressão Atmosférica , Gasometria , Altitude , Sangue
17.
J Dairy Sci ; 103(9): 7761-7774, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32622592

RESUMO

Triglycerides (TG) not only provide energy for infants but have important physiological functions. Understanding the composition and structure of TG in human milk is conducive to the development of infant formulas. In this study, TG species in human milk from 3 provincial capitals (Zhengzhou, Wuhan, and Harbin) in different regions of China were determined through C18 HPLC electrospray ionization tandem mass spectrometry (MS). The results showed that in human milk from these 3 regions, oleoyl-palmitoyl-linoleoylglycerol (OPL; 16.55, 19.20, and 18.67%, respectively) was more abundant than oleoyl-palmitoyl-oleoylglycerol (OPO; 10.08, 10.22, and 12.03%, respectively). Subsequently, regioisomeric and enantiomeric analysis of main TG in the human milk were performed on silver ion and chiral HPLC atmospheric pressure chemical ionization mass spectrometry (APCI)-MS, respectively. The results showed that rac-OPL (above 85%), rac-OPO (above 85%), rac-palmitoyl-oleoyl-oleoylglycerol (PPO; above 90%), and rac-OLaO (above 70%) were the main regioisomers of OPL, OPO, PPO, and lauroyl-oleoyl-oleoylglycerol (LaOO), respectively. The relative ratios of enantiomer pairs of rac-OPL (rac-OPL1 and rac-OPL2) were about 37 and 63%, respectively.


Assuntos
Cromatografia Líquida de Alta Pressão , Leite Humano/química , Triglicerídeos/análise , Adulto , Pressão Atmosférica , Cromatografia Líquida de Alta Pressão/métodos , Feminino , Humanos , Prata , Espectrometria de Massas por Ionização por Electrospray , Estereoisomerismo
18.
BMC Surg ; 20(1): 168, 2020 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-32711489

RESUMO

BACKGROUND: Adhesive small bowel obstruction (ASBO) is one of the most common causes of postoperative morbidity. According to Boyle's law, decreased barometric pressure expands the volume of intestinal gas. We aimed to elucidate the relationship between barometric pressure and ASBO. METHODS: We divided 215 admissions of 120 patients with ASBO into three groups: the fasting group, which responded to fasting (n = 51); the decompression group, which was successfully treated with gastrointestinal decompression (n = 104); and the surgery group which required emergency or elective surgery to treat ASBO (n = 60). We compared and examined clinical backgrounds, findings on admission, and barometric pressure during the peri-onset period (29 days: from 14 days before to 14 days after the onset of ASBO). RESULTS: There were significant differences among the three groups regarding gender, history of ASBO, hospital length of stay, and barometric pressure on the onset day of ASBO. Barometric pressure on the onset day was significantly higher in the fasting group than in the decompression group (p = 0.005). During pre-onset day 5 to post-onset day 2, fluctuations in the barometric pressure in the fasting and decompression groups showed reciprocal changes with a symmetrical axis overlapping the median barometric pressure in Matsumoto City; the fluctuations tapered over time after onset. In the fasting group, the barometric pressure on the onset day was significantly higher than that on pre-onset days 14, 11, 7, 4, 3, and 2; post-onset days 3 and 10; and the median pressure in Matsumoto City. Conversely, in the decompression group, the barometric pressure on the onset day was lower than that on pre-onset days 14, 5-2; post-onset days 1, 2, 7, 8, 11, 13, and 14; and the median pressure in Matsumoto City. In the surgery group, the barometric pressure on the onset day was equivalent to those on the other days. CONCLUSIONS: ASBO with response to conservative treatment is vulnerable to barometric pressure. Additionally, ASBO that is successfully treated with fasting and decompression is associated with a different barometric pressure on the onset day and reciprocal fluctuations in the barometric pressure during the peri-onset period.


Assuntos
Pressão Atmosférica , Obstrução Intestinal , Intestino Delgado/fisiopatologia , Aderências Teciduais/complicações , Idoso , Idoso de 80 Anos ou mais , Jejum/fisiologia , Feminino , Humanos , Obstrução Intestinal/etiologia , Obstrução Intestinal/fisiopatologia , Obstrução Intestinal/cirurgia , Obstrução Intestinal/terapia , Intestino Delgado/patologia , Intestino Delgado/cirurgia , Intubação Gastrointestinal , Japão , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Aderências Teciduais/cirurgia , Resultado do Tratamento
19.
Nat Commun ; 11(1): 3280, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32612128

RESUMO

The atmospheric pressure that decreases with altitude affects lung physiology. However, these changes in physiology are not usually considered in ventilator design and testing. We argue that high altitude human populations require special attention to access the international supply of ventilators.


Assuntos
Altitude , Infecções por Coronavirus/terapia , Desenho de Equipamento , Pneumonia Viral/terapia , Ventiladores Mecânicos/provisão & distribução , Pressão Atmosférica , Betacoronavirus , Infecções por Coronavirus/fisiopatologia , Humanos , Pulmão/fisiologia , Pandemias , Pneumonia Viral/fisiopatologia
20.
J Environ Sci (China) ; 95: 23-32, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32653185

RESUMO

Reaction rate constants and products of 1-octen-3-one, 3-octen-2-one and 4-hexen-3-one with ozone were studied in a 100-L fluorinated ethylene propylene (FEP) Teflon film bag using absolute rate method at 298 ± 1 K and atmospheric pressure. The rate constants were (1.09 ± 0.12) × 10-17, (3.48 ± 0.36) × 10-17 and (5.70 ± 0.60) × 10-17 cm3/(molecule⋅sec), respectively. According to the obtained rate constants, the effects of carbonyl were discussed. The carbonyl group in ß position has a net withdrawing effect with respect to an olefinic bond, then causing the decline of rate constants. The quantum chemical calculation was used to explain the results of rate constants. The products of ozonolysis were mainly aldehydes, which have significant influence on the formation of SOA, and hence play an important role in the atmosphere. In this work, we detected the main products of reaction and proposed the reaction mechanism by combining the results of quantum chemical calculations. Atmospheric lifetime for three unsaturated ketones reacted with ozone was 36.4, 11.4 and 6.9 hr for 1-octen-3-one, 3-octen-2-one and 4-hexen-3-one, respectively.


Assuntos
Atmosfera , Ozônio , Pressão Atmosférica , Cetonas , Cinética
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