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1.
Crit Care Med ; 52(7): 1054-1064, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38537225

RESUMO

OBJECTIVES: Hypophosphatemia occurs frequently. Enteral, rather than IV, phosphate replacement may reduce fluid replacement, cost, and waste. DESIGN: Prospective, randomized, parallel group, noninferiority clinical trial. SETTING: Single center, 42-bed state trauma, medical and surgical ICUs, from April 20, 2022, to July 1, 2022. PATIENTS: Patients with serum phosphate concentration between 0.3 and 0.75 mmol/L. INTERVENTIONS: We randomized patients to either enteral or IV phosphate replacement using electronic medical record-embedded program. MEASUREMENT AND MAIN RESULTS: Our primary outcome was serum phosphate at 24 hours with a noninferiority margin of 0.2 mmol/L. Secondary outcomes included cost savings and environmental waste reduction and additional IV fluid administered. The modified intention-to-treat cohort comprised 131 patients. Baseline phosphate concentrations were similar between the two groups. At 24 hours, mean ( sd ) serum phosphate concentration were enteral 0.89 mmol/L (0.24 mmol/L) and IV 0.82 mmol/L (0.28 mmol/L). This difference was noninferior at the margin of 0.2 mmol/L (difference, 0.07 mmol/L; 95% CI, -0.02 to 0.17 mmol/L). When assigned IV replacement, patients received 408 mL (372 mL) of solvent IV fluid. Compared with IV replacement, the mean cost per patient was ten-fold less with enteral replacement ($3.7 [$4.0] vs. IV: $37.7 [$31.4]; difference = $34.0 [95% CI, $26.3-$41.7]) and weight of waste was less (7.7 g [8.3 g] vs. 217 g [169 g]; difference = 209 g [95% CI, 168-250 g]). C O2 emissions were 60-fold less for comparable phosphate replacement (enteral: 2 g producing 14.2 g and 20 mmol of potassium dihydrogen phosphate producing 843 g of C O2 equivalents). CONCLUSIONS: Enteral phosphate replacement in ICU is noninferior to IV replacement at a margin of 0.2 mmol/L but leads to a substantial reduction in cost and waste.


Assuntos
Estado Terminal , Hipofosfatemia , Fosfatos , Humanos , Hipofosfatemia/economia , Masculino , Feminino , Pessoa de Meia-Idade , Estado Terminal/terapia , Estado Terminal/economia , Fosfatos/sangue , Estudos Prospectivos , Idoso , Nutrição Enteral/economia , Nutrição Enteral/métodos , Hidratação/métodos , Hidratação/economia , Adulto , Custos de Cuidados de Saúde/estatística & dados numéricos , Unidades de Terapia Intensiva
2.
Bull Math Biol ; 85(7): 58, 2023 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-37243841

RESUMO

In this paper, we investigate the disruption of the glucose homeostasis at the whole-body level by the presence of cancer disease. Of particular interest are the potentially different responses of patients with or without hyperglycemia (including diabetes mellitus) to the cancer challenge, and how tumor growth, in turn, responds to hyperglycemia and its medical management. We propose a mathematical model that describes the competition between cancer cells and glucose-dependent healthy cells for a shared glucose resource. We also include the metabolic reprogramming of healthy cells by cancer-cell-initiated mechanism to reflect the interplay between the two cell populations. We parametrize this model and carry out numerical simulations of various scenarios, with growth of tumor mass and loss of healthy body mass as endpoints. We report sets of cancer characteristics that show plausible disease histories. We investigate parameters that change cancer cells' aggressiveness, and we exhibit differing responses in diabetic and non-diabetic, in the absence or presence of glycemic control. Our model predictions are in line with observations of weight loss in cancer patients and the increased growth (or earlier onset) of tumor in diabetic individuals. The model will also aid future studies on countermeasures such as the reduction of circulating glucose in cancer patients.


Assuntos
Diabetes Mellitus Tipo 2 , Diabetes Mellitus , Hiperglicemia , Resistência à Insulina , Neoplasias , Humanos , Glicemia/metabolismo , Insulina/metabolismo , Conceitos Matemáticos , Modelos Biológicos , Hiperglicemia/metabolismo , Hiperglicemia/patologia , Glucose/metabolismo , Modelos Teóricos , Homeostase
3.
Environ Res ; 214(Pt 3): 113995, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35932830

RESUMO

Air pollution is becoming a distinctly growing concern and the most pressing universal problem as a result of increased energy consumption, with the multiplication of the human population and industrial enterprises, resulting in the generation of hazardous pollutants. Among these, carbon monoxide, nitrogen oxides, Volatile organic compounds, Semi volatile organic compounds, and other inorganic gases not only have an adverse impact on human health both outdoors and indoors, but have also substantially altered the global climate, resulting in several calamities around the world. Thus, the purification of air is a crucial matter to deal with. Photocatalytic oxidation is one of the most recent and promising technologies, and it has been the subject of numerous studies over the past two decades. Hence, the photocatalyst is the most reassuring aspirant due to its adequate bandgap and exquisite stability. The process of photocatalysis has provided many benefits to the atmosphere by removing pollutants. In this review, our work focuses on four main themes. Firstly, we briefly elaborated on the general mechanism of air pollutant degradation, followed by an overview of the typical TiO2 photocatalyst, which is the most researched photocatalyst for photocatalytic destruction of gaseous VOCs. The influence of operating parameters influencing the process of photocatalytic oxidation (such as mass transfer, light source and intensity, pollutant concentration, and relative humidity) was then summarized. Afterwards, the progress and drawbacks of some typical photoreactors (including monolithic reactors, microreactors, optical fiber reactors, and packed bed reactors) were described and differentiated. Lastly, the most noteworthy coverage is dedicated to different types of modification strategies aimed at ameliorating the performance of photocatalysts for degradation of air pollutants, which were proposed and addressed. In addition, the review winds up with a brief deliberation for more exploration into air purification photocatalysis.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Ambientais , Compostos Orgânicos Voláteis , Poluição do Ar/prevenção & controle , Catálise , Gases , Humanos , Metais , Titânio
4.
J Fish Dis ; 45(8): 1165-1171, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35598069

RESUMO

White grub metacercariae were found in the livers and kidneys of diseased specimens of an introduced channel catfish, Ictalurus punctatus (Rafinesque), in Vietnam. Based on morphological features and 28S rDNA sequence analysis, the isolated metacercariae were identified as Dollfustrema bagarii (Digenea: Bucephalidae) Moravec & Sey. Histopathological examination shows that encysted metacercariae can change the tissue structure of the infected organs and is often accompanied by haemorrhaging and the presence of eosinophilic granular cell infiltration. Degenerative changes were also observed.


Assuntos
Doenças dos Peixes , Ictaluridae , Trematódeos , Infecções por Trematódeos , Animais , Aquicultura , Metacercárias/genética , Trematódeos/genética , Infecções por Trematódeos/veterinária , Vietnã
5.
Antimicrob Agents Chemother ; 65(12): e0027621, 2021 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-34570647

RESUMO

The rise in Plasmodium falciparum resistance to dihydroartemisinin-piperaquine in Vietnam justifies the need to evaluate alternative artemisinin-based combination therapies. Between July 2018 and October 2019, a single-arm trial of pyronaridine-artesunate (Pyramax, PA) was conducted in Dak Nong province, Vietnam. PA (3-day course) was administered to adults and children infected with P. falciparum. PA was well tolerated by the participants. The proportion of patients with Day 42 PCR-corrected adequate clinical and parasitological response was 95.2% (95% confidence interval [CI], 82.3 to 98.8, n = 40/42) for treating falciparum malaria. The median parasite clearance half-life was 6.7 h (range, 2.6 to 11.9) and the median parasite clearance time was 72 h (range, 12 to 132) with 44.9% (22/49) of patients having positive blood films at 72 h. The two patients that recrudesced had comparable Day 7 blood pyronaridine concentrations (39.5 and 39.0 ng/ml) to the 40 patients who did not recrudesce (median 43.4 ng/ml, 95% CI, 35.1 to 54.9). Ring-stage and piperaquine survival assays revealed that of the 29 P. falciparum isolates collected from the patients before PA treatment, 22 (75.9%) had reduced susceptibility to artemisinins and 17 (58.6%) were resistant to piperaquine. Genotyping confirmed that 92.0% (46/50) of falciparum patients were infected with parasites bearing the Pfkelch13 C580Y mutation associated with artemisinin resistance. Of these, 56.0% (28/50) of the isolates also had multiple copies of the plasmepsin 2/3 genes responsible for piperaquine resistance. Overall, PA was effective in treating P. falciparum in the Central Highlands of Vietnam. (This study has been registered at AustralianClinicalTrials.gov.au under trial ID ACTRN12618001429246.).


Assuntos
Antimaláricos , Artemisininas , Malária Falciparum , Quinolinas , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Artesunato , Combinação de Medicamentos , Humanos , Malária Falciparum/tratamento farmacológico , Naftiridinas , Plasmodium falciparum/genética , Quinolinas/uso terapêutico , Vietnã
6.
Mol Microbiol ; 112(2): 515-531, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31063630

RESUMO

A challenge common to all bacterial pathogens is to acquire nutrients from hostile host environments. Iron is an important cofactor required for essential cellular processes such as DNA repair, energy production and redox balance. Within a mammalian host, most iron is sequestered within heme, which in turn is predominantly bound by hemoglobin. While little is understood about the mechanisms by which bacterial hemophores attain heme from host-hemoglobin, even less is known about intracellular heme processing. Bacillus anthracis, the causative agent of anthrax, displays a remarkable ability to grow in mammalian hosts. Hypothesizing this pathogen harbors robust ways to catabolize heme, we characterize two new intracellular heme-binding proteins that are distinct from the previously described IsdG heme monooxygenase. The first of these, HmoA, binds and degrades heme, is necessary for heme detoxification and facilitates growth on heme iron sources. The second protein, HmoB, binds and degrades heme too, but is not necessary for heme utilization or virulence. The loss of both HmoA and IsdG renders B. anthracis incapable of causing anthrax disease. The additional loss of HmoB in this background increases clearance of bacilli in lungs, which is consistent with this protein being important for survival in alveolar macrophages.


Assuntos
Antraz/microbiologia , Bacillus anthracis/metabolismo , Heme/metabolismo , Antraz/metabolismo , Bacillus anthracis/enzimologia , Bacillus anthracis/genética , Bacillus anthracis/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Humanos , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Ligação Proteica
7.
Eur Respir J ; 56(3)2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32430416

RESUMO

BACKGROUND: Telemonitoring trials for early detection of acute exacerbations of chronic obstructive pulmonary disease (AECOPD) have provided mixed results. Day-to-day variations in lung function measured by the forced oscillation technique (FOT) may yield greater insight. We evaluated the clinical utility of home telemonitoring of variability in FOT measures in terms of 1) the relationship with symptoms and quality of life (QoL); and 2) the timing of variability of FOT measures and symptom changes prior to AECOPD. METHODS: Daily FOT parameters at 5 Hz (resistance (R) and reactance (X); Resmon Pro Diary, Restech Srl, Milan, Italy), daily symptoms (COPD Assessment Test (CAT)) and 4-weekly QoL data (St George's Respiratory Questionnaire (SGRQ)) were recorded over 8-9 months from chronic obstructive pulmonary disease (COPD) patients. Variability of R and X was calculated as the standard deviation (sd) over 7-day running windows and we also examined the effect of varying window size. The relationship of FOT versus CAT and SGRQ was assessed using linear mixed modelling, daily changes in FOT variability and CAT prior to AECOPD using one-way repeated measures ANOVA. RESULTS: Fifteen participants with a mean±sd age of 69±10 years and a % predicted forced expiratory volume in 1 s (FEV1) of 39±10% had a median (interquartile range (IQR)) adherence of 95.4% (79.0-98.8%). Variability of the inspiratory component of X (indicated by the standard deviation of inspiratory reactance (SDXinsp)) related to CAT and weakly to SGRQ (fixed effect estimates 1.57, 95% CI 0.65-2.49 (p=0.001) and 4.41, 95% CI -0.06 to 8.89 (p=0.05), respectively). SDXinsp changed significantly on the same day as CAT (1 day before AECOPD, both p=0.02) and earlier when using shorter running windows (3 days before AECOPD, p=0.01; accuracy=0.72 for 5-day windows). CONCLUSIONS: SDXinsp from FOT telemonitoring reflects COPD symptoms and may be a sensitive biomarker for early detection of AECOPD.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Qualidade de Vida , Volume Expiratório Forçado , Humanos , Itália , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Testes de Função Respiratória
8.
J Sleep Res ; 29(2): e12930, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31633865

RESUMO

Opioid-related deaths from respiratory depression are increasing but there is only limited information on the effect of morphine on breathing during sleep. This study aimed to detect and quantify opioid-induced cardiorespiratory pattern changes during sleep in obstructive sleep apnea (OSA) patients using novel automated methods and correlate these with conventional polysomnography (PSG) measures. Under a randomized double-blind placebo-controlled crossover design, 60 male OSA patients attended two one-night visits to the sleep laboratory, at least a week apart. Either a 40-mg controlled-release oral morphine dose or placebo was administered. Breathing during sleep was measured by standard in-laboratory PSG. We analysed the inter-breath interval (IBI) from the PSG flow channel to quantify breathing irregularity. Cardiopulmonary coupling (CPC) was analysed using the PSG electrocardiogram (ECG) channel. Following the consumption of morphine, the 60 OSA patients had fewer breaths (p = .0006), a longer inter-breath interval (p < .0001) and more irregular breathing with increased IBI coefficient of variation (CV) (p = .0015) compared to the placebo night. A higher CPC sleep quality index was found with morphine use. The change of key IBI and CPC parameters was significantly correlated with the change of key PSG sleep-disordered breathing parameters. In conclusion, 40 mg controlled-release morphine resulted in a longer breathing cycle and increased breathing irregularity but generally more stable sleep in OSA patients. The significant links between the IBI and CPC techniques and a range of PSG sleep-disordered breathing parameters may suggest a practical value as surrogate overnight cardiorespiratory measurements, because both respiratory flow and ECG can be detected by small portable devices.


Assuntos
Analgésicos Opioides/efeitos adversos , Morfina/efeitos adversos , Polissonografia/métodos , Respiração/efeitos dos fármacos , Apneia Obstrutiva do Sono/fisiopatologia , Adolescente , Adulto , Idoso , Analgésicos Opioides/farmacologia , Estudos Cross-Over , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Morfina/farmacologia , Sono/efeitos dos fármacos , Adulto Jovem
9.
Int J Mol Sci ; 21(17)2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32899409

RESUMO

Scaffolds are important to tissue regeneration and engineering because they can sustain the continuous release of various cell types and provide a location where new bone-forming cells can attach and propagate. Scaffolds produced from diverse processes have been studied and analyzed in recent decades. They are structurally efficient for improving cell affinity and synthetic and mechanical strength. Carbon nanotubes are spongy nanoparticles with high strength and thermal inertness, and they have been used as filler particles in the manufacturing industry to increase the performance of scaffold particles. The regeneration of tissue and organs requires a significant level of spatial and temporal control over physiological processes, as well as experiments in actual environments. This has led to an upsurge in the use of nanoparticle-based tissue scaffolds with numerous cell types for contrast imaging and managing scaffold characteristics. In this review, we emphasize the usage of carbon nanotubes (CNTs) and CNT-polymer composites in tissue engineering and regenerative medicine and also summarize challenges and prospects for their potential applications in different areas.


Assuntos
Materiais Biocompatíveis/química , Nanopartículas/química , Nanotubos de Carbono/química , Polímeros/química , Medicina Regenerativa , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Humanos
10.
Asian-Australas J Anim Sci ; 33(10): 1683-1690, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32054190

RESUMO

OBJECTIVE: The rapid and reliable detection of the African swine fever virus (ASFV) plays an important role in emergency control and preventive measures of ASF. Some methods have been recommended by FAO/OIE to detect ASFV in clinical samples, including realtime polymerase chain reaction (PCR). However, mismatches in primer and probe binding regions may cause a false-negative result. Here, a slight modification in probe sequence has been conducted to improve the qualification of real-time PCR based on World Organization for Animal Health (OIE) protocol for accurate detection of ASFV in field samples in Vietnam. METHODS: Seven positive confirmed samples (four samples have no mismatch, and three samples contained one mutation in probe binding sites) were used to establish novel real-time PCR with slightly modified probe (Y = C or T) in comparison with original probe recommended by OIE. RESULTS: Both real-time PCRs using the OIE-recommended probe and novel modified probe can detect ASFV in clinical samples without mismatch in probe binding site. A high correlation of cycle quantification (Cq) values was observed in which Cq values obtained from both probes arranged from 22 to 25, suggesting that modified probe sequence does not impede the qualification of real-time PCR to detect ASFV in clinical samples. However, the samples with one mutation in probe binding sites were ASFV negative with OIE recommended probe but positive with our modified probe (Cq value ranked between 33.12-35.78). CONCLUSION: We demonstrated for the first time that a mismatch in probe binding regions caused a false negative result by OIE recommended real-time PCR, and a slightly modified probe is required to enhance the sensitivity and obtain an ASF accurate diagnosis in field samples in Vietnam.

11.
Brain Behav Immun ; 76: 82-96, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30419269

RESUMO

BACKGROUND: Chronic Fatigue Syndrome (CFS) is one of the most important causes of disability among adolescents while limited knowledge exists on genetic determinants underlying disease pathophysiology. METHODS: We analyzed deregulated immune-gene modules using Pathifier software on whole blood gene expression data (29 CFS patients, 18 controls). Deconvolution of immune cell subtypes based on gene expression profile was performed using CIBERSORT. Supervised consensus clustering on pathway deregulation score (PDS) was used to define CFS subgroups. Associations between PDS and immune, neuroendocrine/autonomic and clinical markers were examined. The impact of plasma norepinephrine level on clinical markers over time was assessed in a larger cohort (91 patients). RESULTS: A group of 29 immune-gene sets was shown to differ patients from controls and detect subgroups within CFS. Group 1P (high PDS, low norepinephrine, low naïve CD4+ composition) had strong association with levels of serum C-reactive protein and Transforming Growth Factor-beta. Group 2P (low PDS, high norepinephrine, high naïve CD4+ composition) had strong associations with neuroendocrine/autonomic markers. The corresponding plasma norepinephrine level delineated 91 patients into two subgroups with significant differences in fatigue score. CONCLUSION: We identified 29 immune-gene sets linked to plasma norepinephrine level that could delineate CFS subgroups. Plasma norepinephrine stratification revealed that lower levels of norepinephrine were associated with higher fatigue. Our data suggests potential involvement of neuro-immune dysregulation and genetic stratification in CFS.


Assuntos
Síndrome de Fadiga Crônica/genética , Síndrome de Fadiga Crônica/imunologia , Norepinefrina/metabolismo , Adolescente , Sistema Nervoso Autônomo/fisiopatologia , Biomarcadores/sangue , Proteína C-Reativa , Linfócitos T CD4-Positivos/imunologia , Estudos de Casos e Controles , Análise por Conglomerados , Síndrome de Fadiga Crônica/metabolismo , Feminino , Expressão Gênica/genética , Redes Reguladoras de Genes/genética , Redes Reguladoras de Genes/imunologia , Humanos , Masculino , Sistemas Neurossecretores/fisiopatologia , Norepinefrina/sangue , Plasma , Transcriptoma/genética
12.
Malar J ; 18(1): 10, 2019 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-30654808

RESUMO

BACKGROUND: Reduced artemisinin susceptibility and artemisinin-based combination therapy (ACT)-resistance against Plasmodium falciparum and chloroquine (CQ)-resistant P. vivax malaria has been reported in Vietnam. Two therapeutic efficacy studies were conducted in Thuan Bac District (Ninh Thuan Province, Vietnam) in 2015 and 2016 to determine the extent of reduced artemisinin susceptibility and ACT resistant falciparum malaria, and CQ-resistant vivax malaria were present. METHODS: Twenty-seven patients with falciparum malaria were randomized to receive artesunate alone (AS ~ 4 mg/kg/day) for 4 days followed by dihydroartemisinin (DHA) (2.2 mg/kg)-piperaquine (PPQ) (18 mg/kg) daily for 3 days or artemether (AM) (1.7 mg/kg)-lumefantrine (LUM) (12 mg/kg) twice daily for 3 days. Sixteen subjects with vivax malaria received CQ (total 25 mg/kg over 3 days). The therapeutic efficacy study for treating falciparum malaria was complemented with molecular analysis for artemisinin and piperaquine resistance, and in vitro drug susceptibility testing. Patient's drug exposure following both falciparum and vivax treatment studies was determined. RESULTS: Twenty-five of 27 patients treated with the artemisinin regimens completed the 42-day follow-up period. None had parasites present on day 3 after commencing treatment with no incidence of recrudescence (100% curative rate). One patient on AS + DHA-PPQ was lost to follow-up and one patient had Plasmodium falciparum and Plasmodium vivax infection on day 0 by PCR. Of the vivax patients, 15 of 16 completed CQ treatment and two had a recurrence of vivax malaria on day 28, a failure rate of 13.3% (2/15). No mutations in the Pfkelch-13 gene for artemisinin resistance or exo-E415G gene polymorphism and amplification in plasmepsins 2 and 3 for piperaquine resistance were observed. In vitro testing of patient's falciparum parasites indicated susceptibility (low IC50 nM values) to dihydroartemisinin, lumefantrine, piperaquine and pyronaridine. Patient's drug exposure to artesunate and lumefantrine was comparable to published data, however, blood CQ concentrations were lower. CONCLUSIONS: Clinical findings, molecular analysis and in vitro testing revealed that the falciparum parasites at Phuoc Chien Commune were artemisinin susceptible. The clinical failure rate of the 15 vivax patients who completed CQ treatment was 13%. Further studies are required to determine whether CQ-resistant vivax malaria is present at the commune.


Assuntos
Antimaláricos/uso terapêutico , Cloroquina/uso terapêutico , Malária Falciparum/tratamento farmacológico , Malária Vivax/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Plasmodium vivax/efeitos dos fármacos , Adolescente , Adulto , Idoso , Antimaláricos/farmacologia , Criança , Pré-Escolar , Cloroquina/farmacologia , Resistência a Múltiplos Medicamentos/genética , Etanolaminas/farmacologia , Etanolaminas/uso terapêutico , Feminino , Fluorenos/farmacologia , Fluorenos/uso terapêutico , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Quinolinas/farmacologia , Quinolinas/uso terapêutico , Reação em Cadeia da Polimerase em Tempo Real , Vietnã/epidemiologia , Adulto Jovem
13.
Phys Chem Chem Phys ; 21(18): 9483-9494, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31016317

RESUMO

Water desalination using positively and negatively charged single-layer nanoporous graphene membranes are investigated using molecular dynamics (MD) simulations. Pressure-driven flows are induced by the motion of specular reflection boundaries with a constant speed, resulting in a prescribed volumetric flow rate. Simulations are performed for 14.40 Å hydraulic pore diameter membrane with four different electric charges distributed on the pore edges. Salt rejection efficiencies and the resulting pressure drops are compared with the previously obtained base-line case of 9.9 Å diameter pristine nanoporous graphene membrane, which exhibits 100% salt rejection with 35.02 MPa pressure drop at the same flow rate. Among the positively charged cases, q = 9e shows 100% and 98% rejection for Na+ and Cl- ions respectively, with 35% lower pressure drop than the reference. For negatively charged pores, optimum rejection efficiencies of 94% and 93% are obtained for Na+ and Cl- ions for the q = -6e case, which requires 60.6% less pressure drop than the reference. The results indicate the high potential of using charged nanoporous graphene membranes in reverse osmosis (RO) desalination systems with enhanced performance.

14.
J Chem Phys ; 151(17): 174705, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31703484

RESUMO

Slip lengths reported from molecular dynamics (MD) simulations of water flow in graphene nanochannels show significant scatter in the literature. These discrepancies are in part due to the used water models. We demonstrate self-consistent comparisons of slip characteristics between the SPC, SPC/E, SPC/Fw, TIP3P, TIP4P, and TIP4P/2005 water models. The slip lengths are inferred using an analytical model that employs the shear viscosity of water and channel average velocities obtained from nonequilibrium MD simulations. First, viscosities for each water model are quantified using MD simulations of counterflowing, force-driven flows in periodic domains in the absence of physical walls. While the TIP4P/2005 model predicts water viscosity at the specified thermodynamic state with 1.7% error, the predictions of SPC/Fw and SPC/E models exhibit 13.9% and 23.1% deviations, respectively. Water viscosities obtained from SPC, TIP4P, and TIP3P models show larger deviations. Next, force-driven water flows in rigid (cold) and thermally vibrating (thermal) graphene nanochannels are simulated, resulting in pluglike velocity profiles. Large differences in the flow velocities are observed depending on the used water model and to a lesser extent on the choice of rigid vs thermal walls. Depending on the water model, the slip length of water on cold graphene walls varied between 34.2 nm and 62.9 nm, while the slip lengths of water on thermal graphene walls varied in the range of 38.1 nm-84.3 nm.

15.
Mycopathologia ; 184(4): 533-538, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31309400

RESUMO

BACKGROUND: A reformulated skin test for coccidioidomycosis, Spherusol®, was recently approved for use in the USA. We hypothesized that it could be useful in predicting severity of illness and outcome in various types of coccidioidomycosis. METHODS: Subjects with non-meningeal coccidioidomycosis attending a clinic in the coccidioidal endemic region were skin tested with Spherusol® and clinical data were collected at the time of testing and at follow-up. RESULTS: Twenty-seven subjects were studied, eight of whom had extrathoracic dissemination. A total of 15 subjects had positive tests, including 11 of 19 subjects with non-disseminated pulmonary disease and four with extrathoracic disseminated coccidioidomycosis. Among those with non-disseminated pulmonary disease, age ≥ 65 years, female sex, and antifungal therapy were significantly associated with a negative test on univariate but not multivariate analysis. For 23 subjects, there was a trend for those not on antifungal therapy at the time of follow-up to have a positive test but no association with coccidioidal complement-fixation titer or overall outcome. CONCLUSIONS: Not all subjects with non-disseminated pulmonary coccidioidomycosis were found to be skin test positive and half of those with extrathoracic disseminated disease manifested dermal hypersensitivity. In this small study, the results of the skin test were not clinically predictive of disease severity or outcome.


Assuntos
Coccidioidina/administração & dosagem , Coccidioidomicose/diagnóstico , Indicadores e Reagentes/administração & dosagem , Testes Cutâneos/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Coccidioidomicose/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
16.
New Phytol ; 217(2): 687-699, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29034957

RESUMO

Root-knot nematodes, Meloidogyne spp., are obligate endoparasites that maintain a biotrophic relationship with their hosts. They infect roots as microscopic vermiform second-stage juveniles, and establish specialized feeding structures called 'giant-cells', from which they withdraw water and nutrients. The nematode effector proteins secreted in planta are key elements in the molecular dialogue of parasitism. Here, we compared Illumina RNA-seq transcriptomes for M. incognita obtained at various points in the lifecycle, and identified 31 genes more strongly expressed in parasitic stages than in preparasitic juveniles. We then selected candidate effectors for functional characterization. Quantitative real-time PCR and in situ hybridizations showed that the validated differentially expressed genes are predominantly specifically expressed in oesophageal glands of the nematode. We also soaked the nematodes in siRNA to silence these genes and to determine their role in pathogenicity. The silencing of the dorsal gland specific-Minc18876 and its paralogues resulted in a significant, reproducible decrease in the number of mature females with egg masses, demonstrating a potentially important role for the small glycine- and cysteine-rich effector MiSGCR1 in early stages of plant-nematode interaction. Finally, we report that MiSGCR1 suppresses plant cell death induced by bacterial or oomycete triggers of plant defense.


Assuntos
Interações Hospedeiro-Parasita , Nicotiana/parasitologia , Parasitos/fisiologia , Raízes de Plantas/parasitologia , Tylenchoidea/fisiologia , Sequência de Aminoácidos , Animais , Morte Celular , Esôfago/metabolismo , Feminino , Perfilação da Expressão Gênica , Inativação Gênica , Proteínas de Helminto/química , Proteínas de Helminto/metabolismo , Interações Hospedeiro-Parasita/genética , Masculino , Especificidade de Órgãos/genética , Parasitos/genética , Células Vegetais/metabolismo , Doenças das Plantas/genética , Doenças das Plantas/parasitologia , Pseudomonas syringae/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Nicotiana/microbiologia , Transcriptoma/genética , Tylenchoidea/genética
17.
J Chem Phys ; 149(2): 024704, 2018 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-30007380

RESUMO

Transport of saltwater through pristine and positively charged single-layer graphene nanoporous membranes is investigated using molecular dynamics simulations. Pressure-driven flows are induced by motion of specular reflecting boundaries at feed and permeate sides with constant speed. Unlike previous studies in the literature, this method induces a desired flow rate and calculates the resulting pressure difference in the reservoirs. Due to the hexagonal structure of graphene, the hydraulic diameters of nano-pores are used to correlate flow rate and pressure drop data. Simulations are performed for three different pore sizes and flow rates for the pristine and charged membrane cases. In order to create better statistical averages for salt rejection rates, ten different initial conditions of Na+ and Cl- distribution in the feed side are used for each simulation case. Using data from 180 distinct simulation cases and utilizing the Buckingham Pi theorem, we develop a functional relationship between the volumetric flow rate, pressure drop, pore diameter, and the dynamic viscosity of saltwater. A linear relationship between the volumetric flow rate and pressure drop is observed. For the same flow rate and pore size, charged membranes exhibit larger pressure drops. Graphene membranes with 9.90 Å pore diameter results in 100% salt rejection with 163.2 l/h cm2 water flux, requiring a pressure drop of 35.02 MPa.

18.
Cult Health Sex ; 20(5): 545-559, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28866956

RESUMO

Poor sexual and reproductive health outcomes among youth are reflective of the many barriers members of this group face in accessing health services. This study provides an in-depth account of the unique challenges that young people face in accessing sexual healthcare services in Vietnam. We surveyed 130 men and women aged 18-24 years at two major reproductive health sites in Ho Chi Minh City. We identified and explored seven domains: health insurance status, modern contraception use, HIV/STI testing, cervical cancer screening, unintended pregnancy, reproductive coercion and the patient-provider relationship. Attitudes towards the national health insurance system suggest that it does not facilitate access to healthcare. Despite widespread and affordable services, fears, fallacies and fixed social mores created formidable barriers for unmarried youth to access sexual and reproductive health services in Vietnam.


Assuntos
Comportamento Contraceptivo/psicologia , Acessibilidade aos Serviços de Saúde , Serviços de Saúde Reprodutiva , Comportamento Sexual , Adulto , Detecção Precoce de Câncer , Feminino , Humanos , Entrevistas como Assunto , Masculino , Gravidez , Inquéritos e Questionários , Migrantes/estatística & dados numéricos , Neoplasias do Colo do Útero/prevenção & controle , Vietnã , Adulto Jovem
19.
J Transl Med ; 15(1): 245, 2017 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-29202780

RESUMO

BACKGROUND: Chronic fatigue syndrome (CFS) is a prevalent and disabling condition among adolescent. The disease mechanisms are unknown. Previous studies have suggested elevated plasma levels of several cytokines, but a recent meta-analysis of 38 articles found that of 77 different cytokines measured in plasma, transforming growth factor beta (TGF-ß) was the only one that was elevated in patients compared to controls in a sufficient number of articles. In the present study we therefore compared the plasma levels of the three TGF-ß isoforms in adolescent CFS patients and healthy controls. In addition, the study explored associations between TGF-ß levels, neuroendocrine markers, clinical markers and differentially expressed genes within the CFS group. METHODS: CFS patients aged 12-18 years (n = 120) were recruited nation-wide to a single referral center as part of the NorCAPITAL project (ClinicalTrials ID: NCT01040429). A broad case definition of CFS was applied, requiring 3 months of unexplained, disabling chronic/relapsing fatigue of new onset, whereas no accompanying symptoms were necessary. Healthy controls (n = 68) were recruited from local schools. The three isoforms of TGF-ß (TGF-ß1, TGF-ß2, TGF-ß3) were assayed using multiplex technology. Neuroendocrine markers encompassed plasma and urine levels of catecholamines and cortisol, as well as heart rate variability indices. Clinical markers consisted of questionnaire scores for symptoms of post-exertional malaise, inflammation, fatigue, depression and trait anxiety, as well as activity recordings. Whole blood gene expression was assessed by RNA sequencing in a subgroup of patients (n = 29) and controls (n = 18). RESULTS: Plasma levels of all three isoforms of TGF-ß were equal in the CFS patients and the healthy controls. Subgrouping according to the Fukuda and Canada 2003 criteria of CFS did not reveal differential results. Within the CFS group, all isoforms of TGF-ß were associated with plasma cortisol, urine norepinephrine and urine epinephrine, and this association pattern was related to fatigue score. Also, TGF-ß3 was related to expression of the B cell annotated genes TNFRSF13C and CXCR5. CONCLUSIONS: Plasma levels of all TGF-ß isoforms were not altered in adolescent CFS. However, the TGF-ß isoforms were associated with neuroendocrine markers, an association related to fatigue score. Furthermore, TGF-ß3 might partly mediate an association between plasma cortisol and B cell gene expression. Trial registration Clinical Trials NCT01040429.


Assuntos
Síndrome de Fadiga Crônica/sangue , Fator de Crescimento Transformador beta/sangue , Adolescente , Biomarcadores/metabolismo , Estudos de Casos e Controles , Demografia , Feminino , Humanos , Modelos Lineares , Masculino , Sistemas Neurossecretores/metabolismo , Isoformas de Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
20.
J Transl Med ; 15(1): 102, 2017 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-28494812

RESUMO

BACKGROUND: Chronic fatigue syndrome (CFS) is a prevalent and disabling condition affecting adolescents. The pathophysiology is poorly understood, but immune alterations might be an important component. This study compared whole blood gene expression in adolescent CFS patients and healthy controls, and explored associations between gene expression and neuroendocrine markers, immune markers and clinical markers within the CFS group. METHODS: CFS patients (12-18 years old) were recruited nation-wide to a single referral center as part of the NorCAPITAL project. A broad case definition of CFS was applied, requiring 3 months of unexplained, disabling chronic/relapsing fatigue of new onset, whereas no accompanying symptoms were necessary. Healthy controls having comparable distribution of gender and age were recruited from local schools. Whole blood samples were subjected to RNA sequencing. Immune markers were blood leukocyte counts, plasma cytokines, serum C-reactive protein and immunoglobulins. Neuroendocrine markers encompassed plasma and urine levels of catecholamines and cortisol, as well as heart rate variability indices. Clinical markers consisted of questionnaire scores for symptoms of post-exertional malaise, inflammation, fatigue, depression and trait anxiety, as well as activity recordings. RESULTS: A total of 29 CFS patients and 18 healthy controls were included. We identified 176 genes as differentially expressed in patients compared to controls, adjusting for age and gender factors. Gene set enrichment analyses suggested impairment of B cell differentiation and survival, as well as enhancement of innate antiviral responses and inflammation in the CFS group. A pattern of co-expression could be identified, and this pattern, as well as single gene transcripts, was significantly associated with indices of autonomic nervous activity, plasma cortisol, and blood monocyte and eosinophil counts. Also, an association with symptoms of post-exertional malaise was demonstrated. CONCLUSION: Adolescent CFS is characterized by differential gene expression pattern in whole blood suggestive of impaired B cell differentiation and survival, and enhanced innate antiviral responses and inflammation. This expression pattern is associated with neuroendocrine markers of altered HPA axis and autonomic nervous activity, and with symptoms of post-exertional malaise. Trial registration Clinical Trials NCT01040429.


Assuntos
Linfócitos B/patologia , Diferenciação Celular/genética , Síndrome de Fadiga Crônica/sangue , Síndrome de Fadiga Crônica/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Adolescente , Biomarcadores/sangue , Estudos de Casos e Controles , Sobrevivência Celular/genética , Criança , Análise por Conglomerados , Estudos Transversais , Síndrome de Fadiga Crônica/imunologia , Feminino , Humanos , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Estatística como Assunto
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