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A novel red phosphor Lu3(1-x)Sc2Ga3O12: xEu3+(0 ≤ x ≤ 0.3) was successfully prepared by high temperature solid state method. The Lu2.4Sc2Ga3O12: 0.2Eu3+ phosphor shows strong high internal quantum efficiency and thermal stability with values of 64.79 % and 87.0 %, respectively. Based on Lu2.4Sc2Ga3O12: 0.2Eu3+ phosphor, the partial replacement of Lu3+ ions in the host by Gd3+ / Y3+ ions changes the local crystal field environment of Eu3+ ions, resulting in wonderful changes in the luminous center, and the luminous intensity at 593 nm is increased by 3.66 and 3.54 times, respectively. The decay time of Eu3+ ions is analyzed from the perspective of dynamics, and the reasons for the enhancement of luminescence after partial replacement of Lu3+ ions are discussed in detail from two aspects of phosphor structure and crystal field effect around Eu3+ ions. In addition, with the substitution of Gd3+ / Y3+ ions, the thermal stability of the sample is 90.3 %/89.4 % with excellent low thermal quenching. The thermal quenching mechanism is described by combining Debye temperature and activation energy. The sample also has a high internal quantum efficiency IQE=79.03 % / 78.24 %. Finally, under the excitation of 365 nm chip, the phosphors of Lu2.34Sc2Ga3O12: 0.2Eu3+, 0.02Gd3+ and Lu2.34Sc2Ga3O12: 0.2Eu3+, 0.02Y3+ synthesized R-LED device has extremely high color rendering index, Ra is 78.23/77.15 and color temperature is 1640.38 K/1642.97 K. The experimental results show that the Lu2.34Sc2Ga3O12: 0.2Eu3+, 0.02Gd3+ / Y3+ phosphors prepared has a wide application prospect in w-LED devices.
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BACKGROUND: Lifelong hypertension highlights the importance of dyadic engagement in coping with the disease. Although dyadic coping is heterogeneous in patients with other diseases, little is known about it in elderly patients with hypertension. In addition, whether impaired dyadic coping is associated with frailty has yet to be elucidated. OBJECTIVES: The aim of this study was to investigate the latent profiles and characteristics of dyadic coping and the potential association between impaired dyadic coping and frailty in elderly patients with hypertension. METHODS: We recruited a total of 741 elderly patients with hypertension. Latent profile analysis was then used to identify the best-fitting model. Then, we used regression analysis to determine profile predictors and identify the association between impaired dyadic coping and frailty. RESULTS: The 5-profile model was considered to be the best-fitting model, as follows: profile 1, severely impaired dyadic coping; profile 2, mildly impaired dyadic coping; profile 3, normal dyadic coping; profile 4, better dyadic coping; and profile 5, the highest dyadic coping. In the fully adjusted model, the probability of frailty was 1.94-fold higher in the mildly impaired dyadic coping group (odds ratio, 1.94; 95% confidence interval, 1.09-3.47) and 2.66-fold higher in the severely impaired dyadic coping group (odds ratio, 2.66; 95% confidence interval, 1.11-6.39). CONCLUSIONS: We identified heterogeneity in dyadic coping and demonstrated that impaired dyadic coping was associated with frailty. Those at risk of dyadic coping impairment need to be identified early, followed by dyadic coping-based interventions to prevent or delay frailty.
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Background: Living with heart failure can severely affect the physical and mental health of patients with heart failure and their caregivers. Available dyadic self-care interventions for heart failure are scarce, especially in China. We aimed to develop and test the family FOCUS programme. Methods: This single-blind, randomised, controlled study was conducted at four hospitals in Tianjin, China. Patients with heart failure (aged at least 18 years) and their caregiver (dyads) were randomly assigned to either the intervention (n = 71) or control (n = 71) group in a 1:1 ratio. The primary outcomes of this study were patient self-care, with three specific dimensions (self-care maintenance, symptom perception, and self-care management), and caregiver contribution to self-care, mirroring these three dimensions. The outcomes were assessed at baseline (T0) and 4 (T1), 12 (T2), and 24 (T3) weeks post-discharge, respectively. This work is registered on ChiCTR, ChiCTR2100053168. Findings: Between May 20, 2022, and September 30, 2022, 142 dyads with heart failure were enrolled. The intervention group exhibited dropout rates of 6%, 8.5%, and 18.3% at 4, 12, and 24 weeks after discharge, while the control group showed 9.9%, 12.3%, and 25.4%. Compared with the control group, patients in the intervention group reported improved self-care maintenance (ß: 8.5, 95% CI: 0.7, 16.4) and management (ß: 7.2, 95% CI: 0.1, 14.3) at T1, as well as improved symptom perception at both T1 (ß: 9.7, 95% CI: 1.5, 17.9) and T2 (ß: 9.6, 95% CI: 0.6, 18.6). Furthermore, caregiver contributions to self-care maintenance, self-care management, and symptom perception (excluding T3) exhibited significant improvements at all timepoints. Interpretation: Although the significant improvements in patients' self-care were not long-lasting, this study suggested that the family FOCUS programme consistently enhanced caregivers' contributions to self-care. Future work could explore the effect of the family FOCUS programme on families with multiple chronic conditions. Funding: The National Natural Science Foundation of China.
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LiYGeO4 phosphors doped with Dy3+ and Eu3+ ions were synthesized using the solid phase method, and their color characteristics were adjustable. The bandgap value of LiYGeO4 calculated by diffuse reflection data is very close to the theoretical value of 3.669 eV, indicating that LiYGeO4 is an ideal candidate for doped rare earth activated ions. The analysis of the emission spectra and fluorescence attenuation curves of Dy3+ and Eu3+ co-doped LiYGeO4 phosphors revealed a clear energy transfer process: energy transfer from Dy3+ to Eu3+. Analysis of emission spectra and fluorescence attenuation curves revealed a transfer of energy from Dy3+ to Eu3+. This transfer mechanism is attributed to the dipole-dipole interactions. In addition, by constantly adjusting the doping levels of Dy3+ and Eu3+, a warm white phosphor with a color temperature of 3881 K was obtained. Finally, the emission intensity of the LiYGeO4:0.015Dy3+,0.02Eu3+ phosphor at 423 K was 86%, indicating that the phosphor has excellent thermal stability and 40% internal quantum efficiency, which proves the potential application of the LiYGeO4 phosphor in white light-emitting diodes (w-LEDs).
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A series of Ca3Al2Ge3O12: xDy3+, yEu3+ phosphors were successfully prepared by the high-temperature solid-phase method. The phase and morphology of the phosphors were studied by means of Rietveld refinement and scanning electron microscopy. The results show that the phase is pure, and the crystal structure is the Ia3Ì d space group. In the Ca3Al2Ge3O12: xDy3+ phosphors, using 380 nm excitation, phosphors showed blue (4F9/2 â 6H15/2) and yellow (4F9/2 â 6H13/2) emission peaks at 481 and 581 nm, respectively. In Ca3Al2Ge3O12: xDy3+, yEu3+ phosphors, the energy transfer was inferred by the spectrum overlap of Dy3+ and Eu3+, and the lifetime attenuation was analyzed from the perspective of dynamics; finally, the band gap structure of the phosphors was analyzed by combining diffuse reflection spectra with the first principle, and the energy transfer mechanism and luminescence mechanism were elaborated by combining theory and practice. The transition from blue white light to red light can be achieved by tuning the range of y in Ca3Al2Ge3O12: 0.015Dy3+, yEu3+. Wherein, when y = 0.07, phosphors, the chromaticity coordinate of warm white CIE is (0.3932, 0.3203), the color temperature is 3093 K, and the warm white light is synthesized. The thermal stability of the synthesized warm white phosphors is 90.1% (423 K), the thermal sensing factors are Samax = 5.51 × 10-4 K-1 (303 K) and Srmax = 0.0359% K-1 (303 K), and the actual quantum efficiency is IQE = 52.48%. These results prove that Ca3Al2Ge3O12: Dy3+, Eu3+ have good application prospects as single-component warm w-LED devices.
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PURPOSE: Patients with heart failure (HF) possess low self-care activation and motivation, leading to a deprived quality of life and adverse mental health conditions. To this end, self-determination theory emphasizes that autonomy-supportive interventions (ASI) can stimulate intrinsic motivation and improve behaviors and quality of life. Nevertheless, studies that focused on ASI for HF are inadequate. This study aims to evaluate the effects of an HF-ASIP on self-care, quality of life and mental health in HF patients. METHODS: In a two-arm randomized controlled trial, the participants are randomly allocated to the intervention (n = 41) or control (n = 41) groups. The intervention group received routine care and participated in an 8-week HF-ASIP, including individual education and consultation sessions. In contrast, the control group received only routine care. The primary outcome includes self-care management, while the secondary outcomes include self-care maintenance, quality of life, mental health, and motivation. After measuring the outcomes at baseline (T0), 4-week (T1), 8-week (T2), and 12-week (T3) follow-up, the intervention effects are assessed using the generalized equation models. RESULTS: The outcomes indicated that self-care management (T2: P = 0.001; T3: P = 0.016), self-care maintenance (T2: P = 0.003; T3: P = 0.001), depression (T2: P = 0.007; T3: P = 0.012), anxiety (T2: P = 0.001; T3: P = 0.012), MLHFQ total score (T1: P = 0.004; T2: P < 0.001; T3: P = 0.001), autonomous motivation (T2: P = .0.006; T3: P = 0.002) showed statistically difference between the groups. CONCLUSION: In summary, the 8-week HF-ASIP significantly improved the attributes of self-care, quality of life, mental health, and motivation in HF patients, suggesting the potential for practical intervention effect. TRIAL REGISTRATION: ChiCTR2100053970.
Subject(s)
Heart Failure , Quality of Life , Humans , Quality of Life/psychology , Mental Health , Self Care , Anxiety/therapy , Heart Failure/therapy , Heart Failure/psychologyABSTRACT
OBJECTIVES: This research investigated the effectiveness of the caregiver-mediated online dignity therapy in enhancing dyadic health and family function. METHODS: Heart failure (HF) family dyads were recruited between May and December 2021 from a university-affiliated hospital in China. The dyads (N=70) were randomly allocated to the intervention group and the control group. We assessed patients' outcomes (hope, well-being, Family APGAR Index and quality of life (QoL)) and their family caregivers' outcomes (anxiety, depression and Family APGAR Index) at baseline (T0), 1 week (T1), 4 weeks (T2) and 8 weeks (T3) after discharge. RESULTS: For patients, the difference over time was significant in QoL (p<0.001). The interaction effects were significant for hope (p<0.001), well-being (p<0.001), Family APGAR Index (p<0.001) and QoL (p=0.007). For family caregivers, a significant difference in depression (p=0.001) was found within groups. Meanwhile, the interaction effects were significant on anxiety (p=0.002) and depression (p=0.016). CONCLUSIONS: Caregiver-mediated online dignity therapy among patients with advanced HF had potential to enhance patient outcomes (level of hope, well-being, family function and QoL) and alleviate caregiver outcomes (anxiety, depression) at 4-week and 8-week follow-up. Thus, we provided scientific evidence for palliative care for advanced HF. TRIAL REGISTRATION NUMBER: ChiCTR2100053758.
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BACKGROUND: Although a growing number of studies have demonstrated that patients' health literacy is associated with health outcomes, the exact relationship between them is not clear. AIMS AND OBJECTIVES: The aim of this study was to explore latent classes of health literacy in patients with heart failure and analyze the differences among different groups. DESIGN AND METHODS: This is a cross-sectional survey. Patients diagnosed with heart failure were selected from 3 tertiary hospitals in Tianjin, China, from March 2019 to November 2019. We measured patients' health literacy using the Health Literacy Scale for Chronic Patients. Latent class analysis was carried out based on the patients' Health Literacy Scale for Chronic Patients scores. Multinomial logistic regression was used to identify the predictive indicators of the latent classes. RESULTS: The health literacy of patients with heart failure was divided into 3 different latent classes, named "high health literacy group," "low literacy high dependence group," and "moderate literacy high willingness group." There were statistically significant differences in gender, age, smoking history, marital status, education level, household income level, and quality of life among different health literacy classes. Low education level and household income level predicted poor health literacy. CONCLUSION: There were 3 latent classes for the health literacy of patients with heart failure. Different health literacy classes exhibited their own distinctive characteristics. Patients in the "moderate literacy high willingness group" had the worst quality of life. Understanding the specific types of health literacy in patients with heart failure facilitates targeted nursing interventions to improve their quality of life.
Subject(s)
Health Literacy , Heart Failure , Humans , Quality of Life , Cross-Sectional Studies , Surveys and Questionnaires , Latent Class Analysis , Heart Failure/therapyABSTRACT
A new P123 templating system is reported for preparing KIT-6s with a large synthesis domain and controllable particle morphology by using benzyl alcohol (Bz) as a co-solvent based on the partitioned cooperative self-assembly (PCSA) principle. As a result, spherical and rod-like KIT-6 can be obtained.
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INTRODUCTION: Living with heart failure (HF), is a shared journey and arduous work for patients and their informal family caregivers. Given the key role and limited evidence of dyad illness management in improving dyad health in the context of HF, we developed a customisable, relationship focused, family online dynamic disease management programme-FOCUS programme-to improve dyad health for HF patients and their informal caregivers in China. METHODS AND ANALYSIS: Based on the Theory of Dyadic Illness Management and the Systemic Transactional Model of Stress and Coping, the family customised online FOCUS programme has five modules: (1) family participatory; (2) open communication; (3) coping effectiveness; (4) uncertainty reduction and 5) shared dyad life stories. HF family dyads will be recruited in the cardiology wards of four university-affiliated hospitals in China. The dyads (N=142) will be randomly allocated to the intervention group that will receive the family customised online FOCUS programme, and the attention control group that will not receive elements of the FOCUS programme. Dyadic coping, HF somatic perception, self-care, anxiety and depression for patients and family caregivers and all-cause mortality and hospital admission for patients will be measured at baseline, 4 weeks (after the discharge, T1), 12 weeks (after the discharge, T2) and 24 weeks (after the discharge, T3). Statistical analysis will be performed using SPSS V. 22.0 software. ETHICS AND DISSEMINATION: The study protocol was approved by the ethics committees of Tianjin Medical University (Reference number TMUHEC2019002) that covers all the centres enrolled in this study. The findings of this study will be published in scientific journals and will be presented at scientific conferences. TRIAL REGISTRATION NUMBER: ChiCTR2100053168.
Subject(s)
Caregivers , Heart Failure , Anxiety/therapy , Heart Failure/therapy , Humans , Quality of Life , Randomized Controlled Trials as Topic , Self Care/methodsABSTRACT
AIMS: Previous prediction studies for 30 day readmission in patients with heart failure were built mainly based on electronic medical records and rarely involved patient-reported outcomes. This study aims to develop and validate a nomogram including patient-reported outcomes to predict the possibility of 30 day all-cause readmission in older patients with heart failure and to explore the value of patient-reported outcomes in prediction model. METHODS AND RESULTS: This was a prospective cohort study. The nomogram was developed and internally validated by Logistic regression analysis based on 381 patients in training group from March to December 2019. The nomogram was externally validated based on 170 patients from July to October 2020. Receiver operating characteristic curves, calibration plots and decision-curve analysis were used to evaluate the performance of the nomogram. A total of 381 patients' complete data were analysed in the training group and 170 patients were enrolled in the external validation group. In the training group, 14.4% (n = 55) patients were readmitted to hospitals within 30 days of discharge and 15.9% (n = 27) patients were readmitted in the external validation group. The nomogram included six factors: history of surgery, changing the type of medicine by oneself, information acquisition ability, subjective support, depression level, quality of life, all of which were significantly associated with 30 day readmission in older patients with heart failure. The areas under the receiver operating characteristic curves of nomogram were 0.949 (95% CI: 0.925, 0.973, sensitivity: 0.873, specificity: 0.883) and 0.804 (95% CI: 0.691, 0.917, sensitivity: 0.778, specificity: 0.832) respectively in the training and external validation groups, which indicated that the nomogram had better discrimination ability. The calibration plots demonstrated favourable coordination between predictive probability of 30 day readmission and observed probability. Decision-curve analysis showed that the net benefit of the nomogram was better between threshold probabilities of 0-85%. CONCLUSIONS: A novel and easy-to-use nomogram is constructed and demonstrated which emphasizes the important role of patient-reported outcomes in predicting studies. The performance of the nomogram drops in the external validation cohort and the nomogram must be validated in a wide prospective cohort of HF patients before its clinical relevance can be demonstrated. All these findings in this study can assist professionals in identifying the needs of HF patients so as to reduce 30 day readmission.
Subject(s)
Heart Failure , Patient Readmission , Humans , Aged , Prognosis , Prospective Studies , Quality of Life , Heart Failure/epidemiology , Heart Failure/therapy , Patient Reported Outcome MeasuresABSTRACT
Glucose-6-phosphate dehydrogenase (G6PDH), the rate-limiting enzyme of the pentose phosphate pathway (PPP), plays a pivotal role in plant stress responses. However, the function and mechanism of G6PDHs in crop plants challenged by fungal pathogens remain poorly understood. In this study, a wheat G6DPH gene responding to infection by Puccinia striiformis f. sp. tritici (Pst), designated TaG6PDH2, was cloned and functionally identified. TaG6PDH2 expression was significantly upregulated in wheat leaves inoculated with Pst or treated with abiotic stress factors. Heterologous mutant complementation and enzymatic properties indicate that TaG6PDH2 encodes a G6PDH protein. The transient expression of TaG6PDH2 in Nicotiana benthamiana leaves and wheat protoplasts revealed that TaG6PDH2 is a chloroplast-targeting protein. Silencing TaG6PDH2 via the barley stripe mosaic virus (BSMV)-induced gene silencing (VIGS) system led to compromised wheat resistance to the Pst avirulent pathotype CYR23, which is implicated in weakened H2O2 accumulation and cell death. In addition, TaG6PDH2 was confirmed to interact with the wheat glutaredoxin TaGrxS4. These results demonstrate that TaG6PDH2 endows wheat with increased resistance to stripe rust by regulating reactive oxygen species (ROS) production.
Subject(s)
Basidiomycota , Triticum , Triticum/metabolism , Glucosephosphate Dehydrogenase/genetics , Glucosephosphate Dehydrogenase/metabolism , Hydrogen Peroxide/metabolism , Basidiomycota/genetics , Gene Silencing , Plant Diseases/genetics , Plant Diseases/microbiology , Disease Resistance/geneticsABSTRACT
Avalanche phenomenon uses critical pump power to produce extreme nonlinear behavior from small disturbances, and has gradually become known. Here, it is reported that the strong green up-conversion emission produced in NaBi(WO4)2 phosphor by the positive feedback enhancement of the energy transfer process. The power dependence indicates that the photon avalanche process has occurred. Contrary to other up-conversion mechanisms, photon avalanche (PA) is a bifurcation phenomenon: avalanches occur above the critical excitation power. The experimental results are analyzed using the rate equation model. The high-response photon avalanche process produced by Yb and Ho ions is discussed in detail. The results show that PA can not only improve the brightness and efficiency of up-conversion, but also has a wider range of applications than traditional up-conversion materials, especially in the detection material of temperature sensor plays an important role.
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BACKGROUND: The incidence of nasal allergy/allergic rhinitis (AR) is rising worldwide, which has become a serious public health problem. Epidemiological studies point that exposure to environmental PM2.5 is closely linked to AR aggravation, however, the exactly mechanism is not clear. This study was performed to reveal molecular mechanisms of PM2.5 -induced AR deterioration. METHODS: Morphology and element analysis of PM2.5 was examined by scanning electron microscopy (SEM) and Energy Dispersive Spectrometer (EDS). A total of 24 female C57BL/6 mice were divided into three groups (control group, AR group, and PM2.5 + AR group, each group contains 8 mice). Mice from AR group and PM2.5 + AR group were intraperitoneally injected with OVA suspension (0.004% OVA+3% aluminum hydroxide) on days 1, 7, and 14. 0.2 mL /kg B.W. for sensitization; then the same mice were intranasal instilled with 5% OVA solution daily for 7 days to established AR mice model (each nostril for 10 µl, day 15-21). The mice were intranasal instilled PBS (control group and AR group, each nostril for 10 µl) or PM2.5 (AR + PM2.5 group, 4.0 mg/kg b.w., each nostril for 10 µl) at the same way from day 23-29. The nasal symptoms were evaluated after the last instillation of PM2.5. Pathological changes and ultrastructure of nasal mucosa were observed by HE staining and SEM. Goblet cells hyperplasia was performed by Periodic acid-Schiff (PAS) staining. NLRP3, Caspase-1, GSDMD and IL-1ß protein expression were assessed by immunohistochemical (IHC) staining. RESULTS: Exposure to PM2.5 aggravated rhinitis symptom, promoted the secretion of serum IgE level and destroyed ultrastructural of nasal mucosa. Interestingly, NLRP3, Caspase-1 GSDMD and IL-1ß protein expression were obviously elevated. NLRP3 /Capase-1/ GSDMD meditated cell pyroptosis participated in the process of AR exacerbation. However, macrophage is not the main effector cell. CONCLUSION: PM2.5 exposure induces aggravation of allergic rhinitis, which is related to NLRP3 inflammasome meditated caspase-1 activation and cell pyroptosis in nasal mucosal.
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The discovery of complete ammonia oxidizer (comammox) was a breakthrough in the study of nitrification. However, slow growth of comammox bacteria makes it challenging to distinguish them from traditional ammonia oxidizing microorganisms. Genomic data indicated that comammox bacteria encoded genes that can metabolize urea and had higher nitrite tolerance, which could only be found in several ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB). This implies that using nitrite and urea as nitrogen sources may accelerate comammox bacteria's enrichment efficiency. In this study, two reactors using nitrite and urea as substrates, respectively, were operated for 390 days. At the end of cultivation, the reactor fed with urea exhibited higher nitrification potential than the reactor fed with nitrite. Comammox bacteria outcompeted AOA and AOB, regardless of whether they were cultured with nitrite or urea. Using nitrite can improve the proportion of comammox amoA to total amoA of 92%, while using urea may increase the proportion of comammox bacteria among total bacteria to 14.2%. Metagenomic results implied that nitrite was converted to ammonia by nitrate reduction and absorbed by comammox bacteria. On the other hand, urea may be directly utilized as substrate. These results demonstrated that using different nitrogen sources caused niche differentiation of comammox bacteria, AOA, and AOB. Using nitrite can increase the relative abundance of comammox amoA to total amoA, while using urea can increase the quantity of comammox amoA. Comammox bacteria were dominant among ammonia oxidizing microorganisms for both nitrite and urea cultures.
Subject(s)
Nitrites , Urea , Ammonia , Archaea/genetics , Bacteria/genetics , Nitrification , Oxidation-Reduction , Phylogeny , Soil MicrobiologyABSTRACT
BACKGROUND: Hepatitis C increases the mortality and morbidity of patients after heart transplant. Direct-acting antivirals (DAAs) are the primary drugs for hepatitis C treatment. However, such drugs are expensive and frequently unaffordable for patients. In DAA treatment, the assessment of drug interaction is crucial. METHODS: We investigated a retrospective case series study from January 2017 to December 2019. Sustained virologic response 12 (SVR12) was used to assess the effectiveness of DAA treatment. Data on patients' demographic information, timing of hepatitis C virus (HCV) infection (before or after heart transplant), HCV genotypes and viral loads, DAAs used (branded drugs or generic drugs), and drug interaction assessments were collected. RESULTS: Fifteen heart transplant patients received hepatitis C treatments during the study period, 11 of whom were infected because their donors had hepatitis C. After DAA treatment, HCV was undetectable in all patients, and 93.3% of them achieved SVR12. Nine patients used the generic sofosbuvir/velpatasvir, and 88.9% of them achieved SVR12. A total of 256 drugs were used with DAAs; 51 records of drug interactions were noted, 3 of which were contraindications, and the remaining records were potential interactions. Patients who used sofosbuvir or elbasvir/grazoprevir experienced fewer drug interactions. CONCLUSIONS: DAA treatment is effective for hepatitis C treatment in patients after heart transplant. Patients who cannot afford branded drugs because of their prices can use generic drugs as an alternative. Drug interactions must be surveyed during DAA treatment.
Subject(s)
Antiviral Agents/therapeutic use , Heart Transplantation , Hepatitis C/drug therapy , Adult , Aged , Drugs, Generic/therapeutic use , Female , Humans , Male , Middle Aged , Retrospective Studies , Sustained Virologic ResponseABSTRACT
Nitrification is important in drinking water treatment plants (DWTPs) for ammonia removal and is widely considered as a stepwise process mediated by ammonia- and nitrite-oxidizing microorganisms. The recent discovery of complete ammonia oxidizers (comammox) has challenged the long-held assumption that the division of metabolic labor in nitrification is obligate. However, little is known about the role of comammox Nitrospira in DWTPs. Here, we explored the relative importance of comammox Nitrospira, canonical ammonia-oxidizing archaea (AOA) and bacteria (AOB) in 12 surface water-fed rapid sand filters (RSFs). Quantitative PCR results showed that all the three ammonia-oxidizing guilds had the potential to dominate nitrification in DWTPs. Spearman's correlation and redundancy analysis revealed that the surface ammonium loading rate (SLR) was the key environmental factor influencing ammonia-oxidizing communities. Comammox Nitrospira were likely to dominate the nitrification under a higher SLR. PCR and phylogenetic analysis indicated that most comammox Nitrospira belonged to clade A, with clade B comammox Nitrospira almost absent. This work reveals obvious differences in ammonia-oxidizing communities between surface water-fed and groundwater-fed RSFs. The presence of comammox Nitrospira can support the stability of drinking water production systems under high SLR and warrants further investigation of their impact on drinking water quality.
Subject(s)
Ammonia , Ammonium Compounds , Archaea/genetics , Nitrification , Oxidation-Reduction , Phylogeny , Sand , WaterABSTRACT
Interleukin-5 (IL-5) strongly initiates the asthmatic inflammatory response, which affects 300 million patients with asthma annually worldwide, through oxidative stress generation. Citrus flavonoids have beneficial properties, such as anti-inflammatory and antioxidant properties, but the precise molecular mechanism of the inhibition of the asthmatic inflammatory response is still unclear. This study aimed to investigate the underlying mechanisms of ROS and IL-5 reduction with citrus flavonoid treatment in PMA/ionomycin-induced EL-4 cells. Our results showed that hesperetin and gardenin A dramatically suppressed ROS and IL-5 production through distinct pathways. Interestingly, hesperidin induced HO-1 expression through the transcription factor Nrf2 coupled with the PI3K/AKT or ERK/JNK signaling pathway, consequently downregulating NFAT activity and IL-5 secretion. Likewise, gardenin A induced HO-1 expression and subsequently suppressed IL-5 production by reducing NFAT activity and upregulating PPARγ in EL-4 cells, suggesting that inducing HO-1 expression may inhibit asthmatic inflammation. Altogether, hesperidin and gardenin A have great potential for regulating the asthma-associated immune responses through antioxidant properties.
Subject(s)
Citrus , Flavonoids/pharmacology , Inflammation/metabolism , Interleukin-5/metabolism , Reactive Oxygen Species/metabolism , Animals , Asthma/metabolism , Cell Line, Tumor/drug effects , Ionomycin , MiceABSTRACT
The intertidal zone is an important buffer and a nitrogen sink between land and sea. Ammonia oxidation is the rate-limiting step of nitrification, conducted by ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB). However, it remains a debatable issue regarding dominant ammonia oxidizers in this region, and environmental factors driving their spatiotemporal niche differentiation have yet to be identified. In this study, intertidal and subtidal zones of Zhoushan Islands were selected for seasonal sampling. Ammonia-oxidizing activity, quantitative PCR, and 454 high-throughput sequencing were performed to study the nitrification potential, abundance, and community structure of ammonia-oxidizing archaea and bacteria. AOA and AOB amoA abundance (107-108amoA gene copies/g dry weight sediment) varied spatiotemporally independently of environmental factors. AOA surpassed AOB in most samples, driven by sediment temperature, moisture, and total nitrogen. The diversity of both AOA and AOB differed spatiotemporally. The Nitrosopumilus and Nitrosospira clusters accounted for an absolutely dominant percentage of AOA (> 99%) and AOB (> 99%) respectively, indicating a negligible contribution of other clusters to ammonia oxidation. However, there was no significant correlation between nitrification potential and the abundance of AOA or AOB. Overall, the present study showed that AOA dominated over AOB spatiotemporally in the intertidal zone of Zhoushan Islands due to fluctuations in environmental factors, and the Nitrosopumilus and Nitrosospira clusters ecologically succeeded in the intertidal zone of Zhoushan Islands.
Subject(s)
Archaea/isolation & purification , Betaproteobacteria/isolation & purification , Geologic Sediments/microbiology , Ammonia/metabolism , Archaea/classification , Archaea/genetics , Archaea/metabolism , Betaproteobacteria/classification , Betaproteobacteria/genetics , Betaproteobacteria/metabolism , China , Ecosystem , Islands , Nitrification , Oxidation-Reduction , PhylogenyABSTRACT
Many studies have shown the effect of solution chemistry on the environmental behavior of metal-based nanoparticles (NPs), except CuO NPs. Here, we investigated the agglomeration, sedimentation, dissolution, and speciation of CuO NPs by varying pH, ionic strength, ionic valence, and natural organic matter (NOM). The results showed that as the pH moved away from 6, the size of CuO agglomerates decreased, along with the enhanced NP suspension stabilization, due to the increase of electrostatic repulsive force. Increasing ionic strength and valence intensified the agglomeration and sedimentation of CuO NPs because of the compression of electrical double layers. The presence of humic acid and citric acid enhanced the dispersion and stabilization of CuO NP suspension, but l-cysteine showed a different impact. Decreasing pH, increasing ionic strength and all NOM improved the dissolution of CuO NPs, but the divalent electrolyte (CaCl2) inhibited the Cu2+ release from CuO NPs compared to the monovalent electrolyte (NaCl). In addition, X-ray absorption near edge structure (XANES) analysis demonstrated that the presence of l-cysteine transformed more than 30% of CuO NPs to Cu(I)-cysteine by coordinating with thiol group. This study can give us an in-depth understanding on the environmental behavior and fate of CuO NPs in the aquatic environment.