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1.
Chemosphere ; 270: 129541, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33429234

RESUMO

Several technologies have been employed to treat greywater (GW) for domestic use. Aerobic biological treatment has achieved high efficiency, the main cost being the necessary source of oxygen (O2). This study explores the effects of lumen air pressure (LAP) on reactor performance and microbial community succession in an O2-based membrane biofilm reactor (O2-MBfR) treating GW. At high LAP (≥0.8 psi), the dissolved oxygen (DO) concentration inside the reactor was higher than 0.38 ± 0.02 mg/L, leading to removal efficiencies of 90%, 98%, and 80%, of total chemical oxygen demand, total linear alkylbenzene sulfonate (LAS), and total nitrogen, respectively. Lower LAP (<0.8 psi) led to a decrease in DO inside the system, and a less effective GW treatment. Low O2 pressure decreased organic biodegradation and ammoniation, and caused LAS accumulation in the biofilm, leading to the solubilization of extracellular polymeric substances and cell lysis. Comprehensive consideration of reactor performance and energy input, DO inside the MBfR at 0.38 ± 0.02 mg/L could be selected as the optimized condition for GW treatment. Microbial community analyses results also revealed that improved LAP was favorable for the enrichment of LAS-biodegradation related genus (Pseudomonas, Parvibaculum, Magnetospirillum, Clostridium, Zoogloea, Dechloromonas and Mycobacterium), nitrifiers (Nitrosomonas and Sphingomonas) and facultative microorganisms (Dechloromonas, Flavobacterium, Pseudomonas, Aeromonas and Zoogloea) that can carry out denitrification under relatively high DO conditions (>0.38 mg/L), but led to the reduction of the relative abundance of heterotrophs (Acidovorax, Thermomonas, Brevundimonas and Enterobacter) that are more sensitive towards high DO conditions.


Assuntos
Oxigênio , Eliminação de Resíduos Líquidos , Pressão do Ar , Biofilmes , Reatores Biológicos , Desnitrificação , Nitrogênio
2.
Anaesthesia ; 76(1): 27-35, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32776518

RESUMO

It is recognised that high-flow nasal therapy can prevent desaturation during airway management. Studies in spontaneously breathing patients show an almost linear relationship between flow rate and positive airway pressure in the nasopharynx. Positive airway pressure has been suggested as one of the possible mechanisms explaining how high-flow nasal therapy works. However, data on pressures generated by high-flow nasal therapy in apnoeic adults under general anaesthesia are absent. This randomised controlled crossover trial investigated airway pressures generated by different flow rates during high-flow nasal therapy in anaesthetised and paralysed apnoeic patients, comparing pressures with closed and open mouths. Following induction of anaesthesia and neuromuscular blockade, a continuous jaw thrust was used to enable airway patency. Airway pressure was measured in the right main bronchus, the middle of the trachea and the pharynx, using a fibreoptically-placed catheter connected to a pressure transducer. Each measurement was randomised with respect to closed or open mouth and different flow rates. Twenty patients undergoing elective surgery were included (mean (SD) age 38 (18) years, BMI 25.0 (3.3) kg.m-2 , nine women, ASA physical status 1 (35%), 2 (55%), 3 (10%). While closed mouths and increasing flow rates demonstrated non-linear increases in pressure, the pressure increase was negligible with an open mouth. Airway pressures remained below 10 cmH2 O even with closed mouths and flow rates up to 80 l.min-1 ; they were not influenced by catheter position. This study shows an increase in airway pressures with closed mouths that depends on flow rate. The generated pressure is negligible with an open mouth. These data question positive airway pressure as an important mechanism for maintenance of oxygenation during apnoea.


Assuntos
Manuseio das Vias Aéreas/métodos , Apneia/terapia , Pressão Positiva Contínua nas Vias Aéreas/métodos , Nasofaringe , Adulto , Pressão do Ar , Anestesia , Estudos Cross-Over , Procedimentos Cirúrgicos Eletivos , Feminino , Tecnologia de Fibra Óptica , Humanos , Masculino , Pessoa de Meia-Idade , Boca , Bloqueio Neuromuscular , Transdutores de Pressão , Resultado do Tratamento , Adulto Jovem
3.
Minerva Anestesiol ; 87(2): 193-198, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33325217

RESUMO

BACKGROUND: The aim was to describe the incidence and risk factors of barotrauma in patients with the Coronavirus disease 2019 (COVID-19) on invasive mechanical ventilation, during the outbreak in our region (Lombardy, Italy). METHODS: The study was an electronic survey open from March 27th to May 2nd, 2020. Patients with COVID-19 who developed barotrauma while on invasive mechanical ventilation from 61 hospitals of the COVID-19 Lombardy Intensive Care Unit network were involved. RESULTS: The response rate was 38/61 (62%). The incidence of barotrauma was 145/2041 (7.1%; 95%-CI: 6.1-8.3%). Only a few cases occurred with ventilatory settings that may be considered non-protective such as a plateau airway pressure >35 cmH2O (2/113 [2%]), a driving airway pressure >15 cmH2O (30/113 [27%]), or a tidal volume >8 mL/kg of ideal body weight and a plateau airway pressure >30 cmH2O (12/134 [9%]). CONCLUSIONS: Within the limits of a survey, patients with COVID-19 might be at high risk for barotrauma during invasive (and allegedly lung-protective) mechanical ventilation.


Assuntos
Barotrauma/epidemiologia , Respiração Artificial/efeitos adversos , Adulto , Pressão do Ar , Barotrauma/diagnóstico por imagem , Barotrauma/etiologia , /terapia , Cuidados Críticos , Feminino , Humanos , Incidência , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , /terapia , Fatores de Risco , Volume de Ventilação Pulmonar , Tomografia Computadorizada por Raios X
4.
A A Pract ; 14(14): e01371, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33350677

RESUMO

Respiratory failure in coronavirus disease 2019 (COVID-19) patients with prolonged endotracheal intubation may require a tracheostomy and percutaneous endoscopic gastrostomy (PEG) tube placement to facilitate recovery. Both techniques are considered high-risk aerosol-generating procedures and present a heightened risk of exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) for operating room personnel. We designed, simulated, and implemented a portable, continuous negative pressure, operative field barrier system using standard equipment available in hospitals to enhance health care provider safety during high-risk aerosol-generating procedures.


Assuntos
/complicações , Endoscopia Gastrointestinal/métodos , Gastrostomia/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Traqueostomia/métodos , Aerossóis , Pressão do Ar , Nutrição Enteral , Filtração , Humanos , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Masculino , Pessoa de Meia-Idade , Salas Cirúrgicas , Isolamento de Pacientes
5.
Medicine (Baltimore) ; 99(45): e23007, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33157945

RESUMO

To examine the effects of temperature on the daily cases of hand, foot, and mouth disease (HFMD).Data on the daily cases of HFMD in Lanzhou from 2008 to 2015 were obtained, and meteorological data from the same period were collected. A distributed lag nonlinear model was fitted to reveal the relationship between the daily mean temperature and the daily cases of HFMD.From 2008 to 2015, 25,644 cases were reported, of which children under 5 years of age accounted for 78.68% of cases. The highest peak of HFMD cases was usually reported between April to July each year. An inverse V-shaped relationship was observed between daily mean temperature and HFMD cases; a temperature of 18°C was associated with a maximum risk of HFMD. The relative risk (RR) was 1.57 (95% confidence interval: 1.23-1.23), and boys and children aged 3 to 5 years were populations with the highest risk. The cumulative risks of high temperature (20.2°C and 25.2°C) in the total, age-specific, and gender-specific groups peaked on lag 14 days; RR was higher in girls than in boys and in children aged 1 to 2 years than in other age groups. However, the effects of low temperature (-5.3°C, 2.0°C, and 12.8°C) were not significant for both gender-specific and age-specific patients.High temperature may increase the risk of HFMD, and boys and children aged 3 to 5 years were at higher risks on lag 0 day; however, the cumulative risks in girls and children aged 1 to 2 years increased with the increasing number of lag days.


Assuntos
Doença de Mão, Pé e Boca/epidemiologia , Temperatura , Adolescente , Pressão do Ar , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Incidência , Lactente , Masculino , Estações do Ano , Tempo (Meteorologia)
12.
Am J Physiol Regul Integr Comp Physiol ; 319(1): R114-R122, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32432914

RESUMO

Exercise-heat acclimation (EHA) induces adaptations that improve tolerance to heat exposure. Whether adaptations from EHA can also alter responses to hypobaric hypoxia (HH) conditions remains unclear. This study assessed whether EHA can alter time-trial performance and/or incidence of acute mountain sickness (AMS) during HH exposure. Thirteen sea-level (SL) resident men [SL peak oxygen consumption (V̇o2peak) 3.19 ± 0.43 L/min] completed steady-state exercise, followed by a 15-min cycle time trial and assessment of AMS before (HH1; 3,500 m) and after (HH2) an 8-day EHA protocol [120 min; 5 km/h; 2% incline; 40°C and 40% relative humidity (RH)]. EHA induced lower heart rate (HR) and core temperature and plasma volume expansion. Time-trial performance was not different between HH1 and HH2 after 2 h (106.3 ± 23.8 vs. 101.4 ± 23.0 kJ, P = 0.71) or 24 h (107.3 ± 23.4 vs. 106.3 ± 20.8 kJ, P > 0.9). From HH1 to HH2, HR and oxygen saturation, at the end of steady-state exercise and time-trial tests at 2 h and 24 h, were not different (P > 0.05). Three of 13 volunteers developed AMS during HH1 but not during HH2, whereas a fourth volunteer only developed AMS during HH2. Heat shock protein 70 was not different from HH1 to HH2 at SL [1.9 ± 0.7 vs. 1.8 ± 0.6 normalized integrated intensities (NII), P = 0.97] or after 23 h (1.8 ± 0.4 vs. 1.7 ± 0.5 NII, P = 0.78) at HH. Our results indicate that this EHA protocol had little to no effect-neither beneficial nor detrimental-on exercise performance in HH. EHA may reduce AMS in those who initially developed AMS; however, studies at higher elevations, having higher incidence rates, are needed to confirm our findings.


Assuntos
Aclimatação , Pressão do Ar , Exercício Físico/fisiologia , Temperatura Alta , Hipóxia/fisiopatologia , Adolescente , Altitude , Doença da Altitude/fisiopatologia , Limiar Anaeróbio , Proteínas de Choque Térmico HSP70/metabolismo , Frequência Cardíaca , Humanos , Umidade , Masculino , Desempenho Físico Funcional , Mecânica Respiratória , Adulto Jovem
14.
Am J Respir Crit Care Med ; 201(9): 1086-1098, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32097569

RESUMO

Rationale: Monitoring and controlling respiratory drive and effort may help to minimize lung and diaphragm injury. Airway occlusion pressure (P0.1) is a noninvasive measure of respiratory drive.Objectives: To determine 1) the validity of "ventilator" P0.1 (P0.1vent) displayed on the screen as a measure of drive, 2) the ability of P0.1 to detect potentially injurious levels of effort, and 3) how P0.1vent displayed by different ventilators compares to a "reference" P0.1 (P0.1ref) measured from airway pressure recording during an occlusion.Methods: Analysis of three studies in patients, one in healthy subjects, under assisted ventilation, and a bench study with six ventilators. P0.1vent was validated against measures of drive (electrical activity of the diaphragm and muscular pressure over time) and P0.1ref. Performance of P0.1ref and P0.1vent to detect predefined potentially injurious effort was tested using derivation and validation datasets using esophageal pressure-time product as the reference standard.Measurements and Main Results: P0.1vent correlated well with measures of drive and with the esophageal pressure-time product (within-subjects R2 = 0.8). P0.1ref >3.5 cm H2O was 80% sensitive and 77% specific for detecting high effort (≥200 cm H2O ⋅ s ⋅ min-1); P0.1ref ≤1.0 cm H2O was 100% sensitive and 92% specific for low effort (≤50 cm H2O ⋅ s ⋅ min-1). The area under the receiver operating characteristics curve for P0.1vent to detect potentially high and low effort were 0.81 and 0.92, respectively. Bench experiments showed a low mean bias for P0.1vent compared with P0.1ref for most ventilators but precision varied; in patients, precision was lower. Ventilators estimating P0.1vent without occlusions could underestimate P0.1ref.Conclusions: P0.1 is a reliable bedside tool to assess respiratory drive and detect potentially injurious inspiratory effort.


Assuntos
Pressão do Ar , Monitoramento Biológico/normas , Inalação/fisiologia , Respiração com Pressão Positiva/normas , Guias de Prática Clínica como Assunto , Respiração Artificial/normas , Trabalho Respiratório/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
15.
Sci Rep ; 10(1): 1837, 2020 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-32020000

RESUMO

Liposomes or biological vesicles can be created from cholesterol, phospholipid, and water. Their stability is affected by their phospholipid composition which can influence disease treatment and drug delivery efficacy. In this study, the effect of phospholipid type on the formation and stability of liposomes using coarse-grained molecular dynamics simulations is investigated. For this purpose, the simulation study of the DSPC (1,2-distearoyl-sn-glycero-3-phosphocholine) and DPSM (Egg sphingomyelin) lipids were considered. All simulations were carried out using the Gromacs software and Martini force field 2.2. Energy minimization (3000 steps) model, equilibrium at constant volume to adjust the temperature at 400 Kelvin and equilibrium at constant pressure to adjust the pressure, at atmospheric pressure (1 bar) have been validated. Microsecond simulations, as well as formation analysis including density, radial distribution function, and solvent accessible surface area, demonstrated spherical nanodisc structures for the DPSM and DSPC liposomes. The results revealed that due to the cylindrical geometric structure and small-size head group, the DSPC lipid maintained its perfectly spherical structure. However, the DPSM lipid showed a conical geometric structure with larger head group than other lipids, which allows the liposome to form a micelle structure. Although the DSPC and DPSM lipids used in the laboratory tests exhibit liposome and micelle behaviors, the simulation results revealed their nanodisc structures. Energy analysis including overall energy, Van der Waals interaction energy, and electrostatic interaction energy showed that DPSM liposome is more stable than DSPC liposome.


Assuntos
Lipossomos/metabolismo , Fosfatidilcolinas/metabolismo , Esfingomielinas/metabolismo , Pressão do Ar , Metabolismo Energético , Nanoestruturas , Eletricidade Estática , Temperatura
16.
BMC Oral Health ; 20(1): 30, 2020 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-32000753

RESUMO

BACKGROUND: Increased composite roughness enhances bacterial adhesion and discoloration, thus increasing the risk of gingival inflammation and secondary caries. Concerns about detrimental effects of sodium bicarbonate on surface roughness influenced the development of less abrasive powders: a glycine-based powder and an erythritol-based powder, additionally - sodium bicarbonate-based powder of reduced grain size. However, there is limited evidence on effects of these materials on the surface of dental fillings. The aim of the present study was to compare the effects of three air-polishing powders (of a reduced abrasiveness) on surface roughness of microhybrid restorative composite material. MATERIAL AND METHODS: Microhybrid light-cure resin composite samples were placed on 64 plaster cubes and light-cured through polyester strips. Surface roughness was measured using laser confocal microscope (magnification 2160x). The specimens were randomly divided into three groups (n = 20, 20 and 24) and air-polished with: sodium bicarbonate (40 µm), glycine (25 µm) and erythritol (14 µm), respectively. Then surface roughness was remeasured, keeping the same field of observation. Specialized 3D analysis software was used for data processing. Parameters according to ISO 25178: Sa, Sq, Sku, Sp, Sv, Sz, Ssk were used to describe surface roughness. RESULTS: Sa, Sq, Sp, Sv, Sz increased significantly following air polishing. Ssk was significantly higher, whereas Sku was significantly lower in sodium bicarbonate and erythritol groups than before air polishing. Comparison between the three powders revealed that Sa was significantly higher in sodium bicarbonate group than in glycine group. Sku was significantly higher in glycine and erythritol groups than in sodium bicarbonate group. CONCLUSIONS: Sodium bicarbonate has a stronger detrimental effect on composite surface than glycine or erythritol. No advantage of erythritol comparing to glycine could be found.


Assuntos
Resinas Compostas , Materiais Dentários/química , Polimento Dentário/métodos , Bicarbonato de Sódio/química , Pressão do Ar , Resinas Compostas/química , Humanos , Teste de Materiais , Pós , Propriedades de Superfície
17.
World Neurosurg ; 138: 84-88, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32001391

RESUMO

BACKGROUND: Colloid cysts are benign and rare tumors of the brain. The growth rates of these tumors are unpredictable. These cysts can increase in size and obstruct the cerebrospinal fluid pathways producing obstructive hydrocephalus. Consequently, this can manifest as acute severe headaches followed by deterioration in consciousness, or even sudden death in patients. Such remarkable episodes occurring in patients during air travel have been reported sparsely in the literature. CASE DESCRIPTION: In this report, we narrate the ordeal of a patient who had severe headache followed by loss of consciousness during his air travel. After his arrival, he was taken to a referral center where the diagnosis of a colloid cyst obstructing the cerebrospinal fluid pathway resulting in acute obstructive hydrocephalus was revealed. We analyze the physiologic effects of cabin pressure and high altitude on the intracranial pressure and present a brief review of the literature. CONCLUSIONS: Changes in cabin pressure during flight may play a role in worsening of intracranial pressure in patients with colloid cyst with marginal brain compliance.


Assuntos
Aviação , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Cistos Coloides/diagnóstico por imagem , Cistos Coloides/cirurgia , Pressão do Ar , Líquido Cefalorraquidiano , Cistos Coloides/complicações , Morte Súbita , Humanos , Hidrocefalia/etiologia , Pressão Intracraniana , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Inconsciência/etiologia
18.
Neurochirurgie ; 66(1): 9-15, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31836487

RESUMO

INTRODUCTION: Subarachnoid hemorrhage (SAH) from intracranial aneurysm rupture is an unpredictable event responsible for significant morbidity and mortality. Despite inconsistencies, some studies suggest a potential role of climate conditions in SAH onset. The purpose of this study was to determine the impact of climatic and lunar factors on onset of SAH in an oceanic climate such as that of Brittany, France. METHODS: All adults with SAH admitted to the neurosurgery department and intensive care unit of the University Hospital of Rennes (France) between January 1st, 2011 and December 31st, 2012 were included. Meteorological variables, their variations, lunar phases and tidal coefficients were compared between days with and without SAH. RESULTS: We retrospectively included 295 patients with SAH. Mean minimum temperature was significantly lower during days with SAH (7.7±4.7°C versus 8.3±4.6°C; P=0.039); temperature variation between 2 successive days was significantly greater for days with SAH (8.6±4.1°C versus 7.9±3.8°C; P<0.01). Multivariate analysis showed that a 2-day temperature drop greater than or equal to 8°C was associated with 35% increased risk of SAH (odds ratio 1.35 [1.03-1.77]). There were no significant effects of other meteorological variables, lunar phase or tidal coefficient on SAH occurrence. CONCLUSION: Low temperature and sudden temperature drop were associated with increased occurrence of SAH in Brittany, France.


Assuntos
Aneurisma Roto/epidemiologia , Clima , Aneurisma Intracraniano/epidemiologia , Adulto , Idoso , Pressão do Ar , Temperatura Baixa , Cuidados Críticos/estatística & dados numéricos , Feminino , França/epidemiologia , Humanos , Aneurisma Intracraniano/complicações , Masculino , Pessoa de Meia-Idade , Lua , Oceanos e Mares , Estudos Retrospectivos , Estações do Ano , Temperatura , Tempo (Meteorologia)
19.
Am J Emerg Med ; 38(6): 1137-1140, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31685304

RESUMO

BACKGROUND: To determine the level of inspiratory pressure minimizing the risk of gastric insufflation while providing adequate pulmonary ventilation. METHODS: In this prospective, randomized, double-blind study, patients were allocated to one of the two groups (P10, P15) defined by the inspiratory pressure applied during controlled-pressure ventilation: 10 and 15 cm H2O. Anesthesia was induced using propofol and sufentanil; no neuromuscular-blocking agent was administered. Once loss of eyelash reflex occurred, facemask ventilation was started for a 2-min period. The cross-sectional antral area was measured using ultrasonography before and after facemask ventilation. Respiratory parameters were recorded. RESULTS: Forty patients were analyzed. Mean tidal volume was about 7 ml/kg in group P10, and was >11 ml/kg in group P15 in the same period. As indicated by ultrasonography test, the antral area in P15 group was markedly incresed compared with P10 group. CONCLUSION: Inspiratory pressure of 10 cm H2O allowed for reduced occurrence of gastric insufflation with proper lung ventilation during induction of anesthesia with sufentanil and propofol in nonparalyzed and nonobese patients.


Assuntos
Anestesia Geral/métodos , Insuflação/efeitos adversos , Complicações Intraoperatórias/prevenção & controle , Máscaras Laríngeas/normas , Respiração Artificial/instrumentação , Estômago/lesões , Pressão do Ar , Estudos Transversais , Método Duplo-Cego , Feminino , Humanos , Complicações Intraoperatórias/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estômago/diagnóstico por imagem , Volume de Ventilação Pulmonar , Ultrassonografia
20.
Int Wound J ; 17(1): 124-131, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31713351

RESUMO

The primary objective was to study pressure ulcer (PU) category II-IV (including suspected deep tissue injury and unstageable PUs) cumulative incidence and PU incidence density, in a 30day observation period, associated with the use of the CuroCell S.A.M. PRO powered reactive air support surface in nursing home residents at risk for PU development. Secondary objectives were to study (a) PU category I cumulative incidence and PU incidence density and (b) user (caregivers and residents) experiences and perceptions of comfort associated with the use of the support surface under study. A multicentre cohort study was set up in 37 care units of 12 Belgian nursing homes. The sample consisted of 191 residents at risk of PU development (Braden score ≤ 17). The cumulative PU incidence was 4.7% (n = 9). The PU incidence density was 1.7/1000 observation days (9 PU/5370 days). The experience and perceptions of comfort analysis revealed that the CuroCell S.A.M. PRO powered reactive air support surface was comfortable for daily use. The mode of action and the quietness of the pump function had a positive impact on sleep quality. Patient comfort and sleep quality are essential criteria in the selection of a support surface.


Assuntos
Pressão do Ar , Leitos , Casas de Saúde/estatística & dados numéricos , Lesão por Pressão/epidemiologia , Lesão por Pressão/prevenção & controle , Medicina Preventiva/instrumentação , Medicina Preventiva/métodos , Idoso , Idoso de 80 Anos ou mais , Bélgica/epidemiologia , Estudos de Coortes , Feminino , Humanos , Incidência , Masculino
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