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In many cases of traumatic brain injury (TBI), conspicuous abnormalities, such as scalp wounds and intracranial hemorrhages, abate over time. However, many unnoticeable symptoms, including cognitive, emotional, and behavioral dysfunction, often last from several weeks to years after trauma, even for mild injuries. Moreover, the cause of such persistence of symptoms has not been examined extensively. Recent studies have implicated the dysregulation of the molecular system in the injured brain, necessitating an in-depth analysis of the proteome and signaling pathways that mediate the consequences of TBI. Thus, in this study, the brain proteomes of two TBI models were examined by quantitative proteomics during the recovery period to determine the molecular mechanisms of TBI. Our results show that the proteomes in both TBI models undergo distinct changes. A bioinformatics analysis demonstrated robust activation and inhibition of signaling pathways and core proteins that mediate biological processes after brain injury. These findings can help determine the molecular mechanisms that underlie the persistent effects of TBI and identify novel targets for drug interventions.
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Lesões Encefálicas Traumáticas , Lesões Encefálicas , Animais , Roedores/metabolismo , Proteômica/métodos , Proteoma/genética , Proteoma/metabolismo , Lesões Encefálicas Traumáticas/metabolismo , Lesões Encefálicas/metabolismoRESUMO
Vacuum-UV (185 nm, VUV) is widely applied to polish reverse osmosis permeate (ROP), such as the production of electronics-grade ultrapure water. In this study, the VUV oxidation of acetaldehyde, a common carbonyl in ROP, was found to be influenced by anions even at low concentrations. Interestingly, the influencing extent and mechanism varied depending on the anions. Bicarbonate minimally affected the VUV-photon absorption and â¢OH consumption, but at 5000 µg-C·L-1, it decreased the degradation of acetaldehyde by 58.7% possibly by scavenging organic radicals or other radical chain reactions. Nitrate strongly competed for VUV-photon absorption and â¢OH scavenging through the formation of nitrite, and at 500 µg-N·L-1, it decreased the removal rate of acetaldehyde degradation by 71.2% and the mineralization rate of dissolved organic carbon by 53.4%. Chloride competed for VUV-photon absorption and also generated reactive chlorine species, which did not affect acetaldehyde degradation but influenced the formation of organic byproducts. The radical chain reactions or activation of anions under VUV irradiation could compensate for the decrease in oxidation performance and need further investigation. In real ROPs, the VUV oxidation of acetaldehyde remained efficient, but mineralization was hindered due to nitrate and chloride anions. This study deepens the understanding of the photochemistry and feasibility of VUV in water with low concentrations of anions.
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Low-pressure mercury lamps with high-purity quartz can emit both vacuum-UV (VUV, 185 nm) and UV (254 nm) and are commercially available and promising for eliminating recalcitrant organic pollutants. The feasibility of VUV/UV as a chemical-free oxidation process was verified and quantitatively assessed by the concept of H2O2 equivalence (EQH2O2), at which UV/H2O2 showed the same performance as VUV/UV for the degradation of trace organic contaminants (TOrCs). Although VUV showed superior H2O activation and oxidation performance, its performance highly varied as a function of light path length (Lp) in water, while that of UV/H2O2 proportionally decreased with decreasing H2O2 dose regardless of Lp. On increasing Lp from 1.0 to 3.0 cm, the EQH2O2 of VUV/UV decreased from 0.81 to 0.22 mM H2O2. Chloride and nitrate hardly influenced UV/H2O2, but they dramatically inhibited VUV/UV. The competitive absorbance of VUV by chloride and nitrate was verified as the main reason. The inhibitory effect was partially compensated by â¢OH formation from the propagation reactions of chloride or nitrate VUV photolysis, which was verified by kinetic modeling in Kintecus. In water with an Lp of 2.0 cm, the EQH2O2 of VUV/UV decreased from 0.43 to 0.17 mM (60.8% decrease) on increasing the chloride concentration from 0 to 15 mM and to 0.20 mM (53.5% decrease) at 4 mM nitrate. The results of this study provide a comprehensive understanding of VUV/UV oxidation in comparison to UV/H2O2, which underscores the suitability and efficiency of chemical-free oxidation with VUV/UV.
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Peróxido de Hidrogênio , Compostos Orgânicos , Oxirredução , Raios Ultravioleta , Peróxido de Hidrogênio/química , Compostos Orgânicos/química , Fotólise , Poluentes Químicos da Água/química , Nitratos/químicaRESUMO
Brominated byproducts and toxicity generation are critical issues for ozone application to wastewater containing bromide. This study demonstrated that ultraviolet/ozone (UV/O3, 100 mJ/cm2, 1 mg-O3/mg-DOC) reduced the cytotoxicity of wastewater from 14.2 mg of pentol/L produced by ozonation to 4.3 mg of pentol/L (1 mg/L bromide, pH 7.0). The genotoxicity was also reduced from 1.65 to 0.17 µg-4-NQO/L by UV/O3. Compared with that of O3 alone, adsorbable organic bromine was reduced from 25.8 to 5.3 µg/L by UV/O3, but bromate increased from 32.9 to 71.4 µg/L. The UV/O3 process enhanced the removal of pre-existing precursors (highly unsaturated and phenolic compounds and poly aromatic hydrocarbons), while new precursors were generated, yet the combined effect of UV/O3 on precursors did not result in a significant change in toxicity. Instead, UV radiation inhibited HOBr concentration through both rapid O3 decomposition to reduce HOBr production and decomposition of the formed HOBr, thus suppressing the AOBr formation. However, the hydroxyl radical-dominated pathway in UV/O3 led to a significant increase of bromate. Considering both organic bromine and bromate, the UV/O3 process effectively controlled both cytotoxicity and genotoxicity of wastewater to mammalian cells, even though an emphasis should be also placed on managing elevated bromate. Futhermore, other end points are needed to evaluate the toxicity outcomes of the UV/O3 process.
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Bromo , Águas Residuárias , Bromo/química , Bromo/toxicidade , Bromatos/química , Processos Fotoquímicos , Raios Ultravioleta , Ozônio/química , Purificação da Água/métodos , Águas Residuárias/toxicidade , Mamíferos , Animais , Células CHO , CricetulusRESUMO
To understand the alkali-metal-dependent material properties of recently discovered AV3Sb5 (A = K, Rb, and Cs), we conducted a detailed electronic structure analysis based on first-principles density functional theory calculations. Contrary to the case of A = K and Rb, the energetic positions of the low-lying Van Hove singularities are reversed in CsV3Sb5, and the characteristic higher-order Van Hove point gets closer to the Fermi level. We found that this notable difference can be attributed to the chemical effect, apart from structural differences. Due to their different orbital compositions, Van Hove points show qualitatively different responses to the structure changes. A previously unnoticed highest lying point can be lowered, locating close to or even below the other ones in response to a reasonable range of bi- and uni-axial strain. Our results can be useful in better understanding the material-dependent features reported in this family and in realizing experimental control of exotic quantum phases.
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Co-processing recycled waste during cement production, i.e., using alternative materials such as secondary raw materials or secondary raw fuels, is widely practiced in developed countries. Alternative raw materials or fuels contain high concentrations of heavy metals and other hazardous chemicals, which might lead to the potential for dangerous heavy metals and hazardous chemicals to be transferred to clinker or cement products, resulting in exposure and emissions to people or the environment. Managing input materials and predicting which inputs affect the final concentration is essential to prevent potential hazards. We used the data of six heavy metals by input raw materials and input fuels of cement manufacturers in 2016-2017. The concentrations of Pb and Cu in cement were about 10-200 times and 4 to 200 times higher than other heavy metals (Cr, As, Cd, Hg), respectively. We profiled the influence of heavy metal concentration of each input material using the principal component analysis (PCA), which analyzed the leading causes of each heavy metal. The Random Forest (RF) ensemble model predicted cement heavy metal concentrations according to input materials. In the case of Cu, Cd, and Cr, the training performance showed R square values of 0.71, 0.71, and 0.92, respectively, as a result of predicting the cement heavy metal concentration according to the heavy metal concentration of each cement input material using the RF model, which is a machine learning model. The results of this study show that the RF model can be used to predict the amount and concentration of alternative raw materials and alternative fuels by controlling the concentration of heavy metals in cement through the concentration of heavy metals in the input materials.
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Cádmio , Metais Pesados , Humanos , Cádmio/análise , Algoritmo Florestas Aleatórias , Metais Pesados/análise , Substâncias Perigosas/análise , Aprendizado de Máquina , Monitoramento Ambiental/métodosRESUMO
Root knot nematodes cause serious damage to global agricultural production annually. Given that traditional chemical fumigant nematicides are harmful to non-target organisms and the environment, the development of biocontrol strategies has attracted significant attention in recent years. In this study, it was found that the Bacillus thuringiensis Berliner strain NBIN-863 exhibits strong fumigant nematicidal activity and has a high attraction effect on Meloidogyne incognita (Kofoid and White) Chitwood. Four volatile organic compounds (VOCs) produced by NBIN-863 were identified using solid-phase microextraction and gas chromatography-mass spectrometry. The nematicidal activity of four VOCs, namely, N-methylformamide, propenamide, 3-(methylthio)propionic acid, and phenylmalonic acid, was detected. Among these compounds, 3-(methylthio)propionic acid exhibited the highest direct contact nematicidal activity against M. incognita, with an LC50 value of 6.27 µg/mL at 24 h. In the fumigant bioassay, the mortality rate of M. incognita treated with 1 mg/mL of 3-(methylthio)propionic acid for 24 h increased to 69.93%. Furthermore, 3-(methylthio)propionic acid also exhibited an inhibitory effect on the egg-hatching of M. incognita. Using chemotaxis assays, it was determined that 3-(methylthio)propionic acid was highly attractive to M. incognita. In pot experiments, the application of 3-(methylthio)propionic acid resulted in a reduction in gall numbers, decreasing the number of galls per gram of tomato root from 97.58 to 6.97. Additionally, the root length and plant height of the treated plants showed significant increases in comparison with the control group. The current study suggests that 3-(methylthio)propionic acid is a novel nematicidal virulence factor of B. thuringiensis. Our research provides evidence for the potential use of NBIN-863 or its VOCs in biocontrol against root knot nematodes.
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Bacillus thuringiensis , Praguicidas , Propionatos , Tylenchoidea , Compostos Orgânicos Voláteis , Animais , Antinematódeos/farmacologia , Praguicidas/farmacologia , Compostos Orgânicos Voláteis/farmacologiaRESUMO
RATIONALE: The high resolving power of the Orbitrap mass spectrometer in a high-resolution accurate mass gas chromatography (HRAM-GC-MS) system provides greater selectivity and sensitivity for the identification and quantification of volatile analytes at low parts per billion (ppb) levels. Hence, it can be applied for the analysis of pharmaceutical impurities like N-nitrosodimethylamine (NDMA) in metformin hydrochloride products (METs). METHODS: Different METs extracted by a dichloromethane/aqueous system were analyzed by HRAM-GC-MS under softer electron ionization (EI) at 30 eV. The accurate masses of NDMA and its internal standard NDMA-d6 were analyzed by full scan and targeted selected ion monitoring modes under 60 000 and 30 000 full width at half maximum at m/z 200, respectively. Data acquisition and processing were managed by Xcalibur and Trace Finder software, respectively. RESULTS: Limits of detection (LOD) and quantification (LOQ) at 10 and 20 ng/g were achieved, which is below the allowed daily intake of 32 ng/g. The mass errors measured from experimental data were within ±2 ppm of the theoretical values over a period of a week. Sample analysis showed that 180 out of 212 samples (85%) were below LOD and 15 out of 212 samples (7 %) were within LOD and LOQ. Only 17 samples (8%) were found to be above LOQ, comprising one active pharmaceutical ingredient (API), five immediate-release METs and 11 extended-released METs. Amongst these, seven extended-release METs and one API exceeded the daily allowed intake, 32 ng/g. CONCLUSIONS: The validated method has been successfully applied for NDMA analysis in various forms of METs. The method is rather straightforward without an additional clean-up step. The scope can also be extended to other volatile impurities in finished pharmaceutical products.
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Metformina , Cromatografia Gasosa-Espectrometria de Massas , Dimetilnitrosamina/análise , Espectrometria de Massas , Preparações FarmacêuticasRESUMO
The structure and "metabolism" (movement and conversion of goods and energy) of urban areas has caused cities to be identified as "super-organisms", placed between ecosystems and the biosphere, in the hierarchy of living systems. Yet most such analogies are weak, and render the super-organism model ineffective for sustainable development of cities. Via a cluster analysis of 15 shared traits of the hierarchical living system, we found that industrialized cities are more similar to eukaryotic cells than to multicellular organisms; enclosed systems, such as factories and greenhouses, paralleling organelles in eukaryotic cells. We further developed a "super-cell" industrialized city model: a "eukarcity" with citynucleus (urban area) as a regulating centre, and organaras (enclosed systems, which provide the majority of goods and services) as the functional components, and cityplasm (natural ecosystems and farmlands) as the matrix. This model may improve the vitality and sustainability of cities through planning and management.
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Ecossistema , Urbanização , CidadesRESUMO
BACKGROUND: To examine the incidence of traumatic spinal cord injury (TSCI) from all etiologies, we measured and compared the incidence of TSCI from three national or quasi-national databases in South Korea, namely, the National Health Insurance Service (NHIS), automobile insurance (AUI), and Industrial Accident Compensation Insurance (IACI). METHODS: We reviewed patients with TSCI reported in the NHIS database between 2009 and 2018, and in the AUI and IACI databases between 2014 and 2018. TSCI patients were defined as those first admitted to the hospital with a diagnosis of TSCI according to the International Classification of Diseases (10th revision) criteria. Age-adjusted incidence was calculated using direct standardization using the 2005 South Korean population or the 2000 US population as the standard population. The annual percentage changes (APC) of TSCI incidence were calculated. The Cochrane-Armitage trend test was performed according to the injured body region. RESULTS: In the NHIS database, age-adjusted TSCI incidence using the Korean standard population increased significantly from 2009 to 2018 (from 33.73 per million in 2009 to 38.14 per million in 2018, APC = 1.2%, P = 0.014). Contrarily, age-adjusted incidence in the AUI database significantly decreased from 13.88 per million in 2014 to 11.57 per million in 2018 (APC = - 5.1%, P = 0.009). In the IACI database, the age-adjusted incidence showed no significant difference, while crude incidence showed a significant increase (from 22.02 per million in 2014 to 28.92 per million in 2018, APC = 6.1%, P = 0.038). According to the age group, all the three databases showed high incidences of TSCI in those in their 60s and 70s or older. Among those in their 70s or older, the incidence of TSCI increased dramatically in the NHIS and IACI databases, while no significant trend was found in AUI database. In 2018, the number of TSCI patients was the highest among those over 70 years of age in the NHIS, whereas among those in their 50s were the highest in both AUI and IACI. The proportion of patients with cervical spinal cord injury was the most common in all these databases. CONCLUSIONS: The differences in trends in the incidence of TSCI may be due to the different etiologies and different characteristics of subjects depending on insurance type. These results imply the need for tailored medical strategies for the different injury mechanisms represented by three national insurance services in South Korea.
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Seguro , Traumatismos da Medula Espinal , Idoso , Idoso de 80 Anos ou mais , Humanos , Acidentes de Trabalho , Automóveis , Incidência , República da CoreiaRESUMO
Tryptophan synthetase (TSase), which functions as a tetramer, is a typical enzyme with a substrate channel effect, and shows excellent performance in the production of non-standard amino acids, histamine, and other biological derivatives. Based on previous work, we fused a mutant CE protein (colistin of E. coli, a polypeptide with antibacterial activity) sequence with the sequence of TSase to explore whether its catalytic activity could be enhanced, and we also analyzed whether the addition of a DNA scaffold was a feasible strategy. Here, dCE (CE protein without DNase activity) protein tags were constructed and fused to the TrapA and TrapB subunits of TSase, and the whole cell was used for the catalytic reaction. The results showed that after the dCE protein tag was fused to the TrapB subunit, its whole cell catalytic activity increased by 50%. Next, the two subunits were expressed separately, and the proteins were bound in vitro to ensure equimolar combination between the two subunits. After the dCE label was fused to TrapB, the activity of TSase assembled with TrapA also improved. A series of experiments revealed that the enzyme fused with dCE9 showed higher activity than the wild-type protein. In general, the activity of assembly TSase was optimal when the temperature was 50 °C and the pH was about 9.0. After a long temperature treatment, the enzyme maintained good activity. With the addition of exogenous nucleic acid, the activity of the enzyme increased. The maximum yield was 0.58 g/L, which was almost three times that of the wild-type TSase (0.21 g/L). The recombinant TSase constructed in this study with dCE fusion had the advantages of higher heat resistance and higher activity, and confirmed the feasibility of adding a nucleic acid scaffold, providing a new idea for the improvement of structurally similar enzymes.
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Ácidos Nucleicos , Triptofano Sintase , Triptofano Sintase/química , Triptofano Sintase/genética , Triptofano Sintase/metabolismo , Escherichia coli/metabolismo , AminoácidosRESUMO
Two series of novel steroidal[17,16-d]pyrimidines derived from natural epiandrosterone and androsterone were designed and synthesized, and these compounds were screened for their potential anticancer activities. The preliminary bioassay indicated that some of these prepared compounds exhibited significantly good cytotoxic activities against human gastric cancer (SGC-7901), lung cancer (A549), and hepatocellular liver carcinoma (HepG2) cell lines compared with 5-fluorouracil (5-FU), epiandrosterone, and androsterone. Especially the respective pairs from epiandrosterone and androsterone showed significantly different inhibitory activities, and the possible configuration-activity relationships have also been summarized and discussed based on kinase assay and molecular docking, which indicated that the inhibition activities of these steroidal[17,16-d]pyrimidines might obviously be affected by the configuration of the hydroxyl group in the part of the steroidal scaffold.
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Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Androsterona/farmacologia , Pirimidinas/farmacologia , Simulação de Acoplamento Molecular , Proliferação de Células , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Esteroides/farmacologia , Fluoruracila/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Relação Estrutura-AtividadeRESUMO
OBJECTIVE: Thyrotropin (TSH) suppression therapy is a standard treatment after surgery for differentiated thyroid carcinoma (DTC). It may be associated with osteoporosis in postmenopausal women. However, there are no guidelines for bone mineral density (BMD) testing intervals to screen for osteoporosis in these patients. Therefore, we evaluated the timing of repeated BMD testing in DTC patients with TSH suppression according to baseline T-scores. DESIGN, PATIENTS, AND MEASUREMENT: We retrospectively evaluated 658 DTC patients who underwent BMD testing more than twice between January 2007 and January 2020. A 1:3 propensity score matching was conducted to compare the timing of repeated BMD tests between the DTC and non-DTC groups. We stratified the participants into four groups based on their baseline T-scores: normal (-1.00 or higher), mild osteopenia (-1.01 to -1.49), moderate osteopenia (-1.50 to -1.99), and severe osteopenia (-2.00 to -2.49). Additionally, the 10% of patients in each group that transitioned to osteoporosis were analysed. RESULTS: The estimated BMD testing interval for 10% of patients who developed osteoporosis was 85 months for patients with initially mild osteopenia, 65 months for those with moderate osteopenia, and 15 months for those with severe osteopenia in the DTC group. In the non-DTC group, the testing intervals for mild, moderate, and severe osteopenia were 98, 57, and 13 months, respectively. On multivariate analysis, baseline T-score (mild osteopenia: hazard ratio [HR] 5.91, p = .105; moderate osteopenia: HR, 25.27, p = .02; and severe osteopenia: HR, 134.82, p < .001) and duration of TSH suppression (tertile 2: HR, 2.25, p = .005; Tertile 3: 1.78, p = .033) were independent risk factors for osteoporosis in the DTC group. CONCLUSION: This study provides guidance for the timing of repeated BMD tests in women over 50 years of age with TSH suppression. The rescreening interval for BMD testing can be modified based on the baseline T-score. The appropriate BMD testing intervals in female DTC patients were similar to those in non-DTC females.
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Doenças Ósseas Metabólicas , Osteoporose , Neoplasias da Glândula Tireoide , Densidade Óssea , Doenças Ósseas Metabólicas/diagnóstico , Doenças Ósseas Metabólicas/etiologia , Feminino , Humanos , Pessoa de Meia-Idade , Osteoporose/diagnóstico , Osteoporose/etiologia , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/tratamento farmacológico , TireotropinaRESUMO
INTRODUCTION: Patients with Parkinson's disease (PD) showed an increased risk of fractures in previous studies and a high prevalence of osteoporosis is reportedly a potential contributor. We conducted a nationwide database study on the risk of fractures and the impact of osteoporosis on patients with PD compared to controls. MATERIALS AND METHODS: Using a nationwide database in South Korea, we identified incident patients with PD in 2004-2006 and selected four age- and sex-matched controls. We checked the occurrence rates of overall and hip fractures and plotted Kaplan-Meier curves and a Cox proportional hazards model to determine risk. We also conducted stratified analyses according to the presence or absence of osteoporosis. RESULTS: We identified 9126 patients with PD and 35,601 controls. Patients with PD had a greater probability of fractures throughout the study period in Kaplan-Meier curves, and an increased risk of overall (aHR 1.35, 95% CI 1.297-1.405) and hip (aHR 1.814, 95% CI 1.66-1.983) fractures in a Cox proportional hazards model. In the stratified analysis, the increased risk of overall fracture (aHR 1.333, 95% CI 1.273-1.396 and aHR 1.412, 95% CI 1.301-1.532, respectively) and hip fracture (aHR 1.773, 95% CI 1.604-1.96 and aHR 2.008, 95% CI 1.657-2.434, respectively) due to PD was similar between patients with and without osteoporosis. DISCUSSION: Patients with PD, with or without osteoporosis, are more likely to experience fractures, especially hip fractures. There seems to be no interaction between PD and osteoporosis in regard to the occurrence of fractures, and therefore no effect modification by osteoporosis.
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Fraturas do Quadril , Osteoporose , Fraturas por Osteoporose , Doença de Parkinson , Fraturas do Quadril/complicações , Fraturas do Quadril/epidemiologia , Humanos , Incidência , Osteoporose/complicações , Osteoporose/epidemiologia , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etiologia , Doença de Parkinson/complicações , Doença de Parkinson/epidemiologia , Modelos de Riscos Proporcionais , Fatores de RiscoRESUMO
BACKGROUND: The co-occurrence of diabetes and osteoporosis is common in postmenopausal women. For the treatment of postmenopausal osteoporosis, current guidelines recommend initial treatment with bisphosphonates, but it is unclear whether bisphosphonates provide a similar degree of therapeutic efficacy in patients with diabetes. This study sought to compare the efficacy of monthly oral ibandronate for retaining bone mineral density (BMD) in diabetic and non-diabetic postmenopausal women with osteoporosis. METHODS: Postmenopausal osteoporotic women with or without diabetes were enrolled in this study from three hospitals in an open-label approach from 2018 to 2020. Each group of patients received oral ibandronate 150 mg once monthly for 1 year. BMD, trabecular bone score (TBS), serum C-terminal telopeptide of type I collagen (CTx) and procollagen type 1 N-terminal propeptide (P1NP) were evaluated prospectively. Treatment-emergent adverse events and changes in glucose metabolism during drug use were also monitored. RESULTS: Among the 120 study participants, 104 (86.7%) completed the study. Following 1 year of treatment, BMD increased by 3.41% vs. 3.71% in the lumbar spine, 1.30% vs. 1.18% in the femur neck, and 1.51% vs. 1.58% in the total hip in the non-diabetes and diabetes groups, respectively. There were no significant differences in BMD changes between the groups, and the differences in CTx or P1NP changes between groups were not significant. We did not observe any significant differences in baseline TBS values or the degree of change between before and after 1 year of ibandronate treatment in either group in this study. A total of 11 adverse events (9.2%) that recovered without sequelae occurred among the 120 included patients, and there was no significant difference in the frequency of adverse events between the groups (p = 0.862). The changes in fasting glucose and glycated hemoglobin levels between before and after treatment were not significant in the diabetic group. CONCLUSIONS: Bisphosphonate therapy showed similar increases in BMD and decreases in CTx and P1NP of postmenopausal women with and without diabetes. Monthly oral ibandronate can be a safe and effective therapeutic option in postmenopausal osteoporosis patients with type 2 diabetes. TRIAL REGISTRATION: NCT number: NCT05266261, Date of registration: 04 March 2022.
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Diabetes Mellitus Tipo 2 , Difosfonatos , Ácido Ibandrônico , Osteoporose Pós-Menopausa , Densidade Óssea , Conservadores da Densidade Óssea/efeitos adversos , Conservadores da Densidade Óssea/uso terapêutico , Diabetes Mellitus Tipo 2/complicações , Difosfonatos/uso terapêutico , Feminino , Humanos , Ácido Ibandrônico/efeitos adversos , Osteoporose Pós-Menopausa/tratamento farmacológico , Estudos Prospectivos , Resultado do TratamentoRESUMO
BACKGROUND: Multiple studies have investigated the association between hyperoxaemia following cardiac arrest (CA) and unfavourable outcomes; however, they have yielded inconsistent results. Most previous studies quantified oxygen exposure without considering its timing or duration. We investigated the relationship between unfavourable outcomes and supranormal arterial oxygen tension (PaO2 ), commonly defined as PaO2 > 100 mmHg, at specific time intervals within 24 h following CA. METHODS: This retrospective observational study included 838 adult non-traumatic patients with CA. The first 24 h following CA were divided into four 6-h time intervals, and the first 6-h period was further divided into three 2-h segments. Multivariable logistic regression analyses were conducted to assess associations of the highest PaO2 and time-weighted average PaO2 (TWA-PaO2 ) values at each time interval with unfavourable outcomes at hospital discharge (cerebral performance categories 3-5). RESULTS: The highest PaO2 (p = .028) and TWA-PaO2 (p = .022) values during the 0-6-h time interval were significantly associated with unfavourable outcomes, whereas those at time intervals beyond 6 h were not. The association was the strongest at supranormal PaO2 values within the 0-2-h time interval, becoming significant at PaO2 values ≥ 150 mmHg. During the first 6 h, longer time spent at ≥150 mmHg of PaO2 was associated with an increased risk of unfavourable outcomes (p = .038). The results were consistent across several sensitivity analyses. CONCLUSION: Supranormal PaO2 during but not after the first 6 h following cardiac arrest was independently associated with unfavourable outcomes.
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Parada Cardíaca , Hiperóxia , Adulto , Humanos , Mortalidade Hospitalar , Oxigênio , Parada Cardíaca/complicações , Parada Cardíaca/terapia , Gasometria/métodos , Estudos RetrospectivosRESUMO
The output of a wavelength-swept laser (WSL) based on a fiber Fabry-Pérot tunable filter (FFP-TF) tends to shift the peak wavelength due to external temperature or heat generated by the FFP-TF itself. Therefore, when measuring the output of WSL for a long time, it is very difficult to accurately measure a signal in the temporal domain corresponding to a specific wavelength of the output of the WSL. If the wavelength variation of the WSL output can be predicted through the peak time information of the forward scan or the backward scan from the WSL, the variation of the peak wavelength can be compensated for by adjusting the offset voltage applied to the FFP-TF. This study presents a successful stabilization method for peak wavelength variation in WSLs by adjusting the offset voltage of the FFP-TF with closed-loop control. The closed-loop control is implemented by measuring the deviation in the WSL peak position in the temporal domain using the trigger signal of the function generator. The feedback repetition rate for WSL stabilization was approximately 0.2 s, confirming that the WSL output and the peak position for the fiber Bragg grating (FBG) reflection spectrum were kept constant within ±7 µs at the maximum when the stabilization loop was applied. The standard deviations of WSL output and reflection peak positions were 1.52 µs and 1.59 µs, respectively. The temporal and spectral domains have a linear relationship; the ±7 µs maximum variation of the peak position corresponded to ±0.035 nm of the maximum wavelength variation in the spectral domain. The proposed WSL system can be used as a light source for temperature or strain-dependent sensors as it compensates for the WSL wavelength variation in applications that do not require a fast scanning rate.
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Broadband wavelength-swept lasers (WSLs) are widely used as light sources in biophotonics and optical fiber sensors. Herein, we present a polygonal mirror scanning wavelength filter (PMSWF)-based broadband WSL using two semiconductor optical amplifiers (SOAs) with different center wavelengths as the gain medium. The 10-dB bandwidth of the wavelength scanning range with 3.6 kHz scanning frequency was approximately 223 nm, from 1129 nm to 1352 nm. When the scanning frequency of the WSL was increased, the intensity and bandwidth decreased. The main reason for this is that the laser oscillation time becomes insufficient as the scanning frequency increases. We analyzed the intensity and bandwidth decrease according to the increase in the scanning frequency in the WSL through the concept of saturation limit frequency. In addition, optical alignment is important for realizing broadband WSLs. The optimal condition can be determined by analyzing the beam alignment according to the position of the diffraction grating and the lenses in the PMSWF. This broadband WSL is specially expected to be used as a light source in broadband distributed dynamic FBG fiber-optic sensors.
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Cholesteric liquid crystals (CLCs) can be applied to various physical and chemical sensors because their alignment structures are changed by external stimuli. Here, we propose a CLC device fabricated by vertically forming the helical axis of the CLC between the cross-sections of two optical fiber ferrules. An optical fiber temperature sensor was successfully implemented using the proposed optical fiber ferrule-based CLC device. A wideband wavelength-swept laser with a center wavelength of 1073 nm and scanning range of 220 nm was used as a light source to measure the variations in the reflection spectrum band according to the temperature change in the CLC cell. The wavelength variation of the reflection spectrum band according to the temperature applied to the CLC cell was reversible and changed linearly with a change in the temperature, and the long-wavelength edge variation rate according to the temperature change was -5.0 nm/°C. Additionally, as the temperature applied to the CLC cell increased, the reflection spectrum bandwidth gradually decreased; the reflection spectrum bandwidth varied at a rate of -1.89 nm/°C. The variations in the refractive indices with temperature were calculated from the band wavelengths of the reflection spectrum. The pitch at each temperature was calculated based on the refractive indices and it gradually decreased as the temperature increased.
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Chitosanase hydrolyzes ß-(1,4)-linked glycosidic bonds are used in chitosan chains to release oligosaccharide mixtures. Here, we cloned and expressed a cold-adapted chitosanase (CDA, Genbank: MW094131) using multi-copy expression plasmids (CDA1/2/3/4) in Pichia pastoris. We identified elevated CDA expression levels in multi-copy strains, with strain PCDA4 selected for high-density fermentation and enzyme-activity studies. The high-density fermentation approach generated a CDA yield of 20014.8 U/mL, with temperature and pH optimization experiments revealing the highest CDA activity at 20 °C and 5.0, respectively. CDA was stable at 10 °C and 20 °C. Thus, CDA could be used at low temperatures. CDA was then displayed on P. pastoris using multi-copy expression plasmids. Then, multi-copy strains were constructed and labelled as PCDA(1-3)-AGα1. Further studies showed that the expression of CDA(1-3)-AGα1 in multi-copy strains was increased, and that strain PCDA3-AGα1 was chosen for high-density fermentation and enzyme activity studies. By using a multi-copy expression and high-density fermentation approach, we observed CDA-AGα1 expression yields of 102415 U/g dry cell weight. These data showed that the displayed CDA exhibited improved thermostability and was more stable over wider temperature and pH ranges than free CDA. In addition, displayed CDA could be reused. Thus, the data showed that displaying enzymes on P. pastoris may have applications in industrial settings.