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1.
J Asthma ; : 1-10, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38865204

RESUMO

OBJECTIVE: Down-regulation of bronchial epithelial E-cadherin is an important of feature of severe asthma, including steroid-insensitive asthma. Yet, the mechanisms involved in E-cadherin disruption are not fully understood. This study was aimed to investigate the role of glucose transporter 1 (GLUT1) in dysregulation of E-cadherin in toluene diisocyanate (TDI)-induced steroid-insensitive asthma. METHODS: A murine model of steroid-insensitive asthma was established by TDI sensitization and aerosol inhalation. Selective GLUT1 antagonists WZB117 and BAY876 were given to BALB/c mice after airway challenge. In vitro, primary human bronchial epithelial cells (HBECs) cultured in an airway-liquid interface (ALI) were exposed to TDI. RESULTS: TDI exposure markedly up-regulated GLUT1 in murine lungs and HBECs. Pharmacological inhibition of GLUT1 with BAY876 decreased airway hyperresponsiveness, neutrophil and eosinophil accumulation, as well as type 2 inflammation in vivo. Besides, the TDI-induced down-regulated expression of full-length E-cadherin was also partly recovered, accompanied by inhibited secretion of soluble E-cadherin (sE-cadherin). WZB117 also exhibited mild therapeutic effects, though not significant. In vitro, treatment with GLUT1 inhibitor relieved the TDI-induced disruption of E-cadherin in HBECs. CONCLUSIONS: Taken together, our data demonstrated that GLUT1 modulates bronchial epithelial E-cadherin dysfunction production in TDI-induced steroid-insensitive asthma.

2.
J Sci Food Agric ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38545920

RESUMO

BACKGROUND: This study investigated per- and polyfluoroalkyl substances (PFASs) in 53 fruit and vegetable samples collected from a local wholesale and retail market in Sydney and a local supermarket in Newcastle. As there is limited information about PFAS levels in vegetables on the market, this study aimed to fill this gap and assess potential risks for humans through consumption of these vegetables. METHODS: QuEChERS extraction - a solid-phase extraction method, a portmanteau word formed from 'quick, easy, cheap, effective, rugged and safe' - followed by enhanced matrix removal-lipid cleaning and liquid chromatography-tandem mass spectrometry analysis were used to detect 30 PFASs in vegetables. RESULTS: PFOA was detected in 7 out of the 53 samples, with concentrations of 0.038-1.996 ng g-1 fresh weight; PFOS was detected in 2 samples only, with concentrations ranging from 0.132 to 0.911 ng g-1 fresh weight. PFHxS was not detected in any sample in this study. PFOA and PFOS concentrations measured in vegetables in this study constituted daily intake of 2.03 ng kg-1 body weight (BW) and 1.98 ng kg-1 BW, respectively, according to recommended daily vegetable intake and BW data from the Australian Bureau of Statistics. The most sensitive population group is girls of 4-8 years of age. These estimated exposure levels represent up to 1.3% of the tolerable daily intake for PFOA (160 ng kg-1 BW) and 9.9% for PFOS (20 ng kg-1 BW) according to Food Standards Australia New Zealand. Consumption of the vegetables from the study locations poses a marginal risk to human health. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

3.
Surg Clin North Am ; 104(2): 437-449, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38453312

RESUMO

This article delves into the role of minimally invasive surgeries in trauma, specifically laparoscopy and video-assisted thoracic surgery (VATS). It discusses the benefits of laparoscopy over traditional laparotomy, including its accuracy in detecting peritoneal violation and intraperitoneal injuries caused by penetrating trauma. The article also explores the use of laparoscopy as an adjunct to nonoperative management of abdominal injuries and in cases of blunt trauma with unclear abdominal injuries. Furthermore, it highlights the benefits of VATS in diagnosing and treating thoracic injuries, such as traumatic diaphragmatic injuries, retained hematomas, and persistent pneumothorax.


Assuntos
Traumatismos Abdominais , Laparoscopia , Traumatismos Torácicos , Ferimentos Penetrantes , Humanos , Traumatismos Torácicos/diagnóstico , Traumatismos Torácicos/cirurgia , Ferimentos Penetrantes/diagnóstico , Ferimentos Penetrantes/cirurgia , Cirurgia Torácica Vídeoassistida , Traumatismos Abdominais/diagnóstico , Traumatismos Abdominais/cirurgia
4.
Life (Basel) ; 14(1)2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38255690

RESUMO

Olfactory dysfunction is associated with conditions such as neurodegenerative diseases, diabetes, obesity, autoimmune diseases, mental illnesses, and upper-airway-related diseases. The COVID-19 pandemic necessitated the development of an examiner-independent olfactory function test. We recently developed a digital olfactory function test called Digitalscent (DIGITAL SCENT), which is a kiosk-type device with an integrated hardware system. The protocol follows conventional psychophysical olfactory function protocols, including threshold, discrimination, and identification test subsets. Eight healthy participants without olfactory dysfunction volunteered for the suitability test and completed both the YSK olfactory function and Digitalscent tests. Pearson correlations were determined between the YSK olfactory function and Digitalscent tests. Digitalscent could be implemented as a conventional olfactory function test, and all participants followed the Digitalscent test protocols. Limitations in the threshold and identification test subsets included unfamiliarity of the patients to the digital test and incompleteness in the sophisticated release of odorants. A strength of the identification test subset was the dual sensory stimulation of vision and olfaction. Digitalscent could-without facilitating viral transmission-enable early diagnosis of olfactory dysfunction during respiratory viral pandemics. Future studies with larger sample sizes are warranted to facilitate wider use of this digital olfactory function test.

5.
Biomed Rep ; 20(1): 11, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38124772

RESUMO

Changes in heart structure and function after lung resection in patients with lung cancer are challenging to manage. Therefore, a non-invasive and reliable measurement tool to gauge such changes is critical. The purpose of the present study was to compare cardiological changes before and after lung resection using tissue Doppler imaging (TDI). A total of 43 patients (19 men and 24 women) with primary non-small cell lung cancer (n=37) and metastatic cancer in the lungs (n=6) were enrolled in the study.nTDI was used to determine the thickness of the ascending aorta, the open size of the ascending valve, the anterior-oposterior diameters of the left atrium and left ventricle, and the thickness of the ventricular septum and right ventricle before and after lung resection. Left ventricular (LV) ejection fraction (EF), pulmonary valve flow rate, tricuspid annular or mitral leaflet tip early (E) peak/late (A) diastolic blood flow velocities, tricuspid regurgitation flow, the lateral mitral annulus early (e') diastolic velocity and mitral E/e' ratio were used to determine LV filling pressure. Results revealed no significant differences between male and female patients in terms of the open size of the ascending valve, the anterior-posterior diameter of the left ventricle and the mitral E/e' ratio. Significant differences were found in the width of the ascending aorta, anterior-posterior diameter of the left atrium, width of the LV septum and right ventricular (RV) diameter before and after lung resection. Finally, there were significantchanges in EF and tricuspid pressure. The results indicated that TDI was useful as a non-invasive method for assessing left and right heart function following lung resection. The LV and RV dimensions were affected, but LV filling pressure was preserved after lobectomy.

6.
Polymers (Basel) ; 15(22)2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-38006146

RESUMO

Bio-polyols (BPOs), characterized by a hydroxyl number up to around 90 mg KOH/g, narrow polydispersity index and relatively low molecular mass up to 2000 g/mol, were synthetized from partially and completely epoxidized soybean and linseed oils and caprylic acid or 3-phenyl butyric acid. These BPOs were used in the presence of toluene diisocyanate to produce polyurethane (PU) foams by using a quasi-prepolymer method involving a two-step reaction. A detailed structural investigation of the prepolymers from toluene diisocyanate and both BPOs and polypropylene glycol was conducted by SEC and solution NMR. The apparent density of the foams was in the range of 40-90 kg/m3, with higher values for foams from the aromatic acid. All the foams showed an open-cell structure with uniform and regular shape and uniform size. The specific Young's moduli and compression deflection values suggest superior mechanical properties than the reference foams. The novel synthesized polyurethanes are excellent candidates to partially replace petroleum-based materials.

7.
Quant Imaging Med Surg ; 13(9): 5877-5886, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37711799

RESUMO

Background: EAS index is reported to be an adjunctive tool for risk stratification in addition to left ventricular ejection fraction (LVEF). This study aimed to verify the predictive value of EAS index among coronary artery disease (CAD) patients with different cardiac systolic function levels. Methods: A total of 477 patients with obstructive CAD were included in the exploratory analysis of a prospective cohort between October 2017 and January 2018 at Guangdong Provincial People's Hospital. EAS index, e'/(a' × s'), is a novel parameter assessed by tissue Doppler imaging (TDI) indicating combined diastolic and systolic performance. Any occurrence of major adverse cardiovascular event (MACE) was recorded, including first onset of myocardial infarction, stroke, readmission for heart failure, coronary revascularization, or cardiovascular death that occurred within 6 months of the first admission. Kaplan-Meier survival and Cox regression analyses were applied to testify the predictive value of EAS index for cardiovascular outcome. Results: A total of 415 patients (87.2%) completed the follow-up (median, 25.9 months) and experienced 101 (24.3%) MACEs, 17 (4.0%) deaths, and 139 (33.4%) composite events. Elevated EAS index was significantly associated with a higher incidence of MACE, even after adjustment for age, sex, body mass index, N-terminal pro brain natriuretic peptide, high-sensitivity troponin T, high-density lipoprotein, stenosis degree, and other TDI parameters [Model 3, hazard ratio: 1.81, 95% confidence interval (CI): 1.15-2.85]. For different levels of cardiac function, Kaplan-Meier survival analysis revealed that elevated EAS index was associated with higher MACE incidence only in patients with LVEF ≥50% (P<0.05). Conclusions: EAS index is an independent predictor of MACE in patients with obstructive CAD, which could be utilized as a tool for risk stratification in CAD patients or incorporated into a prediction model to improve efficacy.

8.
Materials (Basel) ; 16(18)2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37763534

RESUMO

In this study, polyol castor oil (CO) and toluene-2,4-diisocyanate (TDI) were selected to modify PBAT, and castor-oil-based polyurethane (COP) was produced in a PBAT matrix using melt-blending and hot-pressing technology to study the effect of network cross-linking structure on various properties of bio-based polyester PBAT, aiming to introduce CO and TDI to improve the mechanical properties of composite materials. The results showed that when the total addition of CO and TDI was 15%, and the ratio of the hydroxyl group of CO to the isocyanate group of TDI was 1:1, the mechanical properties were the best. The tensile strength of the composite was 86.19% higher than that of pure PBAT, the elongation at break was 70.09% higher than that of PBAT, and the glass transition temperature was 7.82 °C higher than that of pure PBAT. Therefore, the composite modification of PBAT by CO and TDI can effectively improve the heat resistance and mechanical properties of PBAT-based composites.

9.
J Am Dent Assoc ; 154(9): 805-813.e1, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37480926

RESUMO

BACKGROUND: Children with traumatic dental injuries (TDIs) may simultaneously sustain a traumatic brain injury (TBI). The aim of this study was to investigate the risk of concomitant TBI in children with TDIs. METHODS: Children (≤ 18 years) who sought treatment at the emergency department of a major children's hospital for TDIs from 2010 through 2019 were identified. Children with a concomitant TBI were assigned as case patients (TDI and TBI). Two control patients (TDI only) were randomly age- and sex-matched with each case patient. Associations between variables of TDI and concomitant TBI were tested using 6 logistic regression models. RESULTS: Of 2,126 children with TDIs, 119 had concomitant TBIs (case patients). The control group consisted of 238 children with TDIs only who were age- and sex-matched with case patients. Mean (SD) age of children was 8.9 (4.8) years. Twenty-seven percent of case patients were female vs 32% of control patients. There was a statistically significant direct association between total number of injured teeth and concomitant TBIs (P = .01; odds ratio, 2.42; 95% CI, 1.22 to 4.79). For every tooth injured, the odds of concomitant TBI increased by 45% (P < .001; odds ratio, 1.45; 95% CI, 1.18 to 1.79). Number of displaced teeth, presence of avulsion or intrusion, number of fractured teeth, presence of complicated tooth fracture, and presence of alveolar fracture were not significantly associated with the odds of concomitant TBI. CONCLUSIONS: The total number of injured teeth was positively associated with higher odds of concomitant TBI in this setting. PRACTICAL IMPLICATIONS: In an emergency department setting, children with various types of TDIs sustained concomitant TBIs. For every tooth injured, the odds of concomitant TBI increased by 45%. Clinicians must systematically evaluate children with any TDI to rule out the possibility of concomitant TBI.


Assuntos
Lesões Encefálicas Traumáticas , Humanos , Criança , Feminino , Masculino , Estudos de Casos e Controles , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/epidemiologia , Serviço Hospitalar de Emergência , Assistência Odontológica , Modelos Logísticos
10.
Clin Res Cardiol ; 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37522900

RESUMO

BACKGROUND: Color tissue Doppler imaging (TDI) M-mode can be used to measure the cardiac time intervals including the isovolumic contraction time (IVCT), the left ventricular ejection time (LVET), the isovolumic relaxation time (IVRT), and the combination of all the cardiac time intervals in the myocardial performance index (MPI) defined as [(IVCT + IVRT)/LVET]. The aim of this study was to establish normal age- and sex-based reference ranges for the cardiac time intervals. METHODS AND RESULTS: A total of 1969 participants free of cardiovascular diseases and risk factors from the general population with limited age range underwent an echocardiographic examination including TDI. The median age was 46 years (25th-75th percentile: 33-58 years), and 61.5% were females. In the entire study population, the IVCT was observed to be 40 ± 10 ms [95% prediction interval (PI) 20-59 ms], the LVET 292 ± 23 ms (95% PI 248-336 ms), the IVRT 96 ± 19 ms (95% PI 59-134 ms) and MPI 0.47 ± 0.09 (95% PI 0.29-0.65). All the cardiac time intervals differed significantly between females and males. With increasing age, the IVCT increased in females, but not in males. The LVET did not change with age in both sexes, while the IVRT increased in both sexes with increasing age. Furthermore, we developed regression equations relating the heart rate to the cardiac time intervals and age- and sex-based normal reference ranges corrected for heart rate. CONCLUSION: In this study, we established normal age- and sex-based reference ranges for the cardiac time intervals. These normal reference ranges differed significantly with sex.

11.
Environ Monit Assess ; 195(7): 807, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37278915

RESUMO

In the present study, we developed a new Swedish phosphorus diatom index (PDISE) to improve the poor fit of existing indices to match the needs of water managers to detect and mitigate eutrophication. We took advantage of a large amount of data (820 Swedish stream sites) collected in recent years. During our work, we found an unexpected bimodal response of the diatom assemblages to phosphorus. The taxa clustered either into an assemblage with a low or with a high site-specific averaged TP optimum (a calculated value comprised of the diatom taxa-specific optima). We could not find a characteristic diatom assemblage for sites with intermediate site-specific averaged TP optima. To our knowledge, this bimodal community response has not been shown earlier. The PDISE correlated more strongly than the currently used TDI to changes in TP concentrations. Thus, the PDISE should replace the TDI in the Swedish standard method. The modeled TP optima (expressed as categories) were different compared to the TDI for most of the taxa included in the index, indicating that the realized niche for these morphotaxa was different between Sweden and the UK where the TDI was developed originally. With a r2 of 0.68, the correlation of the PDISE to TP is among the highest reported for other diatom nutrient indices globally; thus, we believe that it might be worth to test it for other bioregions with similar geography and climate.


Assuntos
Diatomáceas , Rios , Monitoramento Ambiental/métodos , Fósforo/análise , Água Doce , Ecossistema
12.
Echocardiography ; 40(7): 670-678, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37261862

RESUMO

BACKGROUND: Although measures of longitudinal displacement of the tricuspid annulus measured by M-mode as tricuspid annular systolic plane excursion (TAPSE) and systolic velocity by tissue Doppler imaging (TA TDI s) are routinely used for assessment of right ventricular (RV) systolic function; these measures describe different phenomena and should not be used interchangeably. METHODS: Previously published data was used to determine the individual relationship between TAPSE and TA TDI s with increasing pulmonary artery systolic pressures (PASP). RESULTS: In this retrospective analysis, 488 patients were divided into 2 groups based on TAPSE (Group 1: <1.8 cm and Group 2: ≥1.8 cm). A robust correlation (R = .79) between TAPSE and TA TDI s noted for the entire population. However, a statistically lower correlation (R = .43) was seen between Group 1 and Group 2 (R = .65; p < .0047). With increasing pulmonary pressures, only PASP (p < .0001) and TA TDI s (p < .0001) discriminated between low and normal TAPSE/PASP values. Suggesting that a TA TDI s/PASP ratio would be most useful than TAPSE/PASP with a specificity of 80%. CONCLUSIONS: Significant differences exist between TAPSE and TA TDI s, particularly at low TAPSE values with increased PASP, were uncoupling occurs. Our data seems to suggest that TA TDI s/PASP would be most useful than TAPSE/PASP ratio. Future studies should address, if abnormalities in the material properties along the RV free wall account for these differences seen between TAPSE and TA TDI s.


Assuntos
Disfunção Ventricular Direita , Função Ventricular Direita , Humanos , Estudos Retrospectivos , Estudos Prospectivos , Sístole , Disfunção Ventricular Direita/diagnóstico por imagem
13.
Int J Cardiol ; 386: 141-148, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37178800

RESUMO

BACKGROUND: The cardiac time intervals include the isovolumic contraction time (IVCT), the left ventricular ejection time (LVET), the isovolumic relaxation time (IVRT) and the combination of all the cardiac time intervals in the myocardial performance index (MPI) (defined as [(IVCT+IVRT)/LVET)]. Whether the cardiac time intervals change over time and which clinical factors that accelerate these changes is not well-established. Additionally, whether these changes are associated with subsequent heart failure (HF), remains unknown. METHODS: We investigated participants from the general population (n = 1064) who had an echocardiographic examination including color tissue Doppler imaging performed in both the 4th and 5th Copenhagen City Heart Study. The examinations were performed 10.5 years apart. RESULTS: The IVCT, LVET, IVRT and MPI increased significantly over time. None of the investigated clinical factors were associated with increase in IVCT. Systolic blood pressure (standardized ß= - 0.09) and male sex (standardized ß= - 0.08) were associated with an accelerated decrease in LVET. Age (standardized ß=0.26), male sex (standardized ß=0.06), diastolic blood pressure (standardized ß=0.08), and smoking (standardized ß=0.08) were associated with an increase in IVRT, while HbA1c (standardized ß= - 0.06) was associated with a decrease in IVRT. Increasing IVRT over a decade was associated with an increased risk of subsequent HF in participants aged <65 years (per 10 ms increase: HR 1.33; 95%CI (1.02-1.72), p = 0.034). CONCLUSION: The cardiac time increased significantly over time. Several clinical factors accelerated these changes. An increase in IVRT was associated with an increased risk of subsequent HF in participants aged <65 years.


Assuntos
Insuficiência Cardíaca , Humanos , Masculino , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/epidemiologia , Ecocardiografia , Pressão Sanguínea
14.
EFSA J ; 21(4): e06857, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37089179

RESUMO

In 2015, EFSA established a temporary tolerable daily intake (t-TDI) for BPA of 4 µg/kg body weight (bw) per day. In 2016, the European Commission mandated EFSA to re-evaluate the risks to public health from the presence of BPA in foodstuffs and to establish a tolerable daily intake (TDI). For this re-evaluation, a pre-established protocol was used that had undergone public consultation. The CEP Panel concluded that it is Unlikely to Very Unlikely that BPA presents a genotoxic hazard through a direct mechanism. Taking into consideration the evidence from animal data and support from human observational studies, the immune system was identified as most sensitive to BPA exposure. An effect on Th17 cells in mice was identified as the critical effect; these cells are pivotal in cellular immune mechanisms and involved in the development of inflammatory conditions, including autoimmunity and lung inflammation. A reference point (RP) of 8.2 ng/kg bw per day, expressed as human equivalent dose, was identified for the critical effect. Uncertainty analysis assessed a probability of 57-73% that the lowest estimated Benchmark Dose (BMD) for other health effects was below the RP based on Th17 cells. In view of this, the CEP Panel judged that an additional uncertainty factor (UF) of 2 was needed for establishing the TDI. Applying an overall UF of 50 to the RP, a TDI of 0.2 ng BPA/kg bw per day was established. Comparison of this TDI with the dietary exposure estimates from the 2015 EFSA opinion showed that both the mean and the 95th percentile dietary exposures in all age groups exceeded the TDI by two to three orders of magnitude. Even considering the uncertainty in the exposure assessment, the exceedance being so large, the CEP Panel concluded that there is a health concern from dietary BPA exposure.

15.
Toxicol Rep ; 10: 348-356, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36923442

RESUMO

One route of human exposure to environmental chemicals is oral uptake. This is primarily true for chemicals that may leach from food packaging materials, such as bisphenols and phthalate esters. Upon ingestion, these compounds are transported along the intestinal tract, from where they can be taken up into the blood stream or distributed to mucosal sites. At mucosal sites, mucosal immune cells and in the blood stream peripheral immune cells may be exposed to these chemicals potentially modulating immune cell functions. In the present study, we investigated the impact of three common bisphenols and two phthalate esters on mucosal-associated invariant T (MAIT) cells in vitro, a frequent immune cell type in the intestinal mucosae and peripheral blood of humans. All compounds were non-cytotoxic at the chosen concentrations. MAIT cell activation was only slightly affected as seen by flow cytometric analysis. Phthalate esters did not affect MAIT cell gene expression, while bisphenol-exposure induced significant changes. Transcriptional changes occurred in ∼ 25 % of genes for BPA, ∼ 22 % for BPF and ∼ 8 % for BPS. All bisphenols down-modulated expression of CCND2, CCL20, GZMB and IRF4, indicating an effect on MAIT cell effector function. Further, BPA and BPF showed a high overlap in modulated genes involved in cellular stress response, activation signaling and effector function suggesting that BPF may not be safe substitute for BPA.

16.
Molecules ; 28(4)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36838779

RESUMO

Polyethylene glycols (PEG) and toluene diisocyanate (TDI) are often used as the main components of binders and curing agents in solid propellants, and their aging is an important issue in the storage and use of propellants. To study the aging behavior and aging mechanism of nitrate ester plasticized polyether propellant (NEPE) matrix during storage, the transition states of aging reactions of binder and curing agent were optimized at the (U)B3LYP/6-311G(d,p) level of theory, and the rate coefficients over the temperature range of 298-1000 K were calculated by CVT theory. The results showed that there were five kinds of aging reactions for binder, which included decomposition, nitration, H abstraction, oxidation, and crosslinking reactions. Among them, theenergy barriers of oxidation and H abstraction reactions were relatively low (79.3-91.2 kJ·mol-1) and the main reaction types of binder aging. The main aging reaction of curing agent was decomposition. Compared with the aging reactions of binder, the energy barriers of curing agent are higher (196.6-282.7 kJ·mol-1) and the reaction is more difficult to occur. By comparing the energy barriers and rate constants of different reactions, it is found that the aging of NEPE propellant matrix can be divided into two stages. In the first stage, the propellant matrix mainly undergoes H abstraction and oxidation reaction, and as the reaction proceeds, the products crosslink to form -O-O-, -C-C-, and -C-O-C- bonds. At this time, the long chain molecules of the propellant matrix crosslink, and the molecular weight increases. This stage corresponds to the rising stage of mechanical properties in the aging process of the propellant. In the second stage, the propellant matrix mainly undergoes decomposition and nitration, resulting in degradation, the reduction of molecular weights, and the appearance of holes and microcracks in the matrix. This stage corresponds to the decline of mechanical properties in the aging process of the propellant. The above simulation results are in good agreement with the aging experimental phenomena, revealing the microscopic mechanism of the changes in the macroscopic properties of NEPE propellant during the aging process, and providing a theoretical basis for the related research on the aging properties and anti-aging technology of NEPE propellant.


Assuntos
Nitratos , Simulação por Computador , Oxirredução
17.
Egypt Heart J ; 75(1): 12, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36780088

RESUMO

BACKGROUND: Low-level laser therapy (LLLT) is a promising noninvasive physiotherapeutic approach that has been demonstrated to improve cardiac performance. This study aimed to assess the impact of low-level laser therapy on cardiac functions and clinical status in patients with chronic left ventricular systolic heart failure who were not candidates for cardiac revascularization or resynchronization. A case series of 27 patients received a course of low-level laser physiotherapy, the clinical outcomes, echocardiographic parameters, and serum nitric oxide levels were evaluated before and after LLLT. RESULTS: Of the total patients enrolled in the study, 21 (or 77.8%) were male, with a mean age of 57.7 ± 6.89 years. NYHA classification significantly improved after low-level laser therapy, 15 patients were in class III,12 were in class IV, and no one was in class II before laser therapy while after laser therapy; 25 patients shifted to class II, two patients were in class III with P < 0.001, Six-minute walk distance test was performed, and the results showed that the mean of 6MWT was less than 200 m (148.556 ± 39.092) before the study but increased to more than 300 after laser therapy (385.074 ± 61.740), left ventricular ejection fraction before laser therapy was 26 ± 7.5 while after laser therapy it became 30 ± 8.6 but diastolic function did not change after low-level laser therapy, the mean peak TR pressure was 40.0 ± 9.0 mmHg and 33.0 ± 7.0 before and after laser therapy respectively P < 0.001. A significant change was observed in NO level from 4.1 ± 1.4 IU/ml before laser therapy to 5.2 ± 1.7 IU/ml after laser therapy P < 0.001. CONCLUSIONS: Low-level laser therapy may add benefits to improve symptoms, clinical condition, and quality of life in patients with left ventricular systolic dysfunction, further studies are necessary to evaluate the changes in cardiac functions at a longer follow-up duration.

18.
Eur J Pediatr ; 182(4): 1555-1559, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36719478

RESUMO

To investigate the development of diaphragmatic dysfunction in ventilated extremely preterm infants (EPI) using diaphragm ultrasound (DU). EPI of less than 28 weeks' gestational age who required mechanical ventilation within six hours of birth were included in this prospective, observational study. DU was performed once a day until four days of life. End-inspiratory and end-expiratory thicknesses of the diaphragm were measured, and the diaphragm thickening fraction was calculated. A total of 20 EPI were enrolled. After intubation, there was a progressive reduction in end-inspiratory thickness of the diaphragm from baseline to day 1 (P < 0.001), but not from day 1 to day 2 (P = 0.092), day 2 to day 3 (P = 1.0), or day 3 to day 4 (P = 1.0). There was also a significant reduction in the diaphragm thickening fraction from baseline to day 1 (P < 0.001), but not from day 1 to day 2 (P = 1.0), day 2 to day 3 (P = 1.0), or day 3 to day 4 (P = 1.0).    Conclusions: This study provides the first evidence of diaphragmatic dysfunction in ventilated EPI. We demonstrated a rapid progression of ventilator-induced diaphragmatic dysfunction, with a significant reduction in diaphragm thickness and thickening fraction within 24 h of ventilation. What is Known: • Over-assistance of the ventilator suppresses respiratory effort and induces diaphragm unloading, resulting in diaphragm atrophy or dysfunction. • Diaphragmatic dysfunction contributes to prolonged ventilator dependence and poor clinical outcomes. What is New: • Most extremely preterm infants develop diaphragmatic dysfunction after intubation within 24 hours. • Diaphragm thickness and contraction ability measured by ultrasound would be important indicators of worsening breathing or respiratory outcomes.


Assuntos
Diafragma , Lactente Extremamente Prematuro , Recém-Nascido , Lactente , Humanos , Diafragma/diagnóstico por imagem , Estudos Prospectivos , Respiração Artificial/efeitos adversos , Ventiladores Mecânicos
19.
Orthop Traumatol Surg Res ; 109(2): 103311, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35523373

RESUMO

INTRODUCTION: The Total Disability Index (TDI) questionnaire has been developed to provide a more complete assessment of low back and neck pain, as they frequently co-occur. This study aimed at validating the TDI questionnaire in French, to determine if it could be used in France. HYPOTHESIS: The TDI French version is valid, reproducible and comparable to the English version. METHODS: This multicentric study prospectively included French-speaking volunteers, both patients admitted for spine surgery in two specialized spine centers and healthy individuals. Healthy subjects were recruited among students of an engineering school and medical staff. A booklet was given to the participants containing a Lumbar and Cervical Visual Analog Scale (respectively LVAS and CVAS), and the French versions of Oswestry Disability Index (ODI), Neck Disability Index (NDI) and TDI questionnaires. Statistical analysis included Cronbach's α calculation for internal consistency assessment, correlation analysis with ODI and NDI items for convergent validity, principal component analyses and factor analysis. Discriminant validity was assessed by comparing healthy subjects and patients using Student's t tests, and floor and ceiling effects search. RESULTS: 71 participants were included, with 34 (48%) healthy volunteers and 37 (52%) patients. Mean age was 45.2±19.6 years and 57% of the cohort were males. Internal consistency was good: Cronbach's α was calculated at 0.96 (95%CI: [0.95-0.98]). For each TDI item, a high correlation was found with ODI corresponding items, between 0.81 and 0.97 (p<0.001), and good correlation with NDI items, ranging from 0.65 to 0.96 (p<0.001). TDI correlated also with LVAS and CVAS (respectively 0.70 and 0.65, p<0.001). Principal component analyses indicated good correlation between the TDI items and between each item and TDI total score. Factor analysis indicated two main factors explaining 77% of TDI variance, constituted by all TDI items. Regarding discriminative validity, healthy subjects and patients presented significantly different TDI scores (p-values ≤0.01 for each item). Barplot representations of each TDI item revealed no major floor nor ceiling effects. CONCLUSION: This study confirms the reliability, feasibility and validity of the Total Disability Index questionnaire in its French version. Its validation allows its use in France. LEVEL OF EVIDENCE: II.


Assuntos
Avaliação da Deficiência , Cervicalgia , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Feminino , Reprodutibilidade dos Testes , Nível de Saúde , Inquéritos e Questionários , Psicometria
20.
Dent Traumatol ; 39(2): 109-118, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36317716

RESUMO

BACKGROUND/AIM: Participation in sports activities is a source of dental injury. Despite recommendations for the use of mouthguards, athletes underutilize them. The aim of this study was to provide estimates of dental injuries, the mechanism of injuries and the utilization of mouthguards in high school sports. MATERIALS AND METHODS: This study was a secondary analysis of an existing dataset of a convenience sample of the National High School Sports-Related Injury Surveillance Study. Data of athletic exposures, dental injuries, mouthguard usage, and mechanism of injury from the 2005/2006 to the 2019/2020 academic years were analyzed. RESULTS: During the study period, there were 459 dental injuries in 49,987,927 athletic exposures resulting in a dental injury rate of 0.9 per 100,000 athletic exposures (AE). Slightly more than half of the traumatic dental injuries were sustained during competition (n = 256; 55.8%) and the rest (n = 200; 43.6%) were sustained during practice. The rate of dental injury in competition was 3.6 times higher than the rate in practice (RR: 3.6, 95% CI: 3.0-4.4). Dental injuries comprised 0.4% of the total 108,574 injuries sustained by athletes. Among girls' sports, field hockey had the highest rate (3.5 per 100,000 AE) and among boys' sports, basketball (2.4 per 100,000 AE) had the highest rate of dental injury. The most common mechanism of injury was contact with another player (276; 60.4%) followed by contact with apparatus (146; 31.9%). In the majority of dental injuries (308; 75.1%), the athlete was not wearing a mouthguard when the dental injury was sustained. CONCLUSIONS: Dental injuries were a small proportion of all injuries sustained by high school athletes. The majority of dental injuries were sustained when the athlete was not wearing a mouthguard.


Assuntos
Traumatismos em Atletas , Basquetebol , Traumatismos Dentários , Masculino , Feminino , Humanos , Estados Unidos , Traumatismos em Atletas/epidemiologia , Instituições Acadêmicas , Atletas , Basquetebol/lesões , Incidência
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