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1.
Biomedicines ; 12(7)2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-39061970

RESUMO

Clostridioides difficile infection (CDI) worsens inflammatory bowel disease (IBD) prognosis. While fecal microbiota transplantation (FMT) is effective for refractory or recurrent CDI (rrCDI), comparative success rates between IBD and non-IBD patients are scarce. This study addresses this gap. A retrospective cohort study was conducted at Chang Gung Memorial Hospital from April 2019 to October 2023. Patients receiving FMT for rrCDI were categorized into IBD and non-IBD groups. Baseline characteristics and outcomes were compared at one month and one year, with successful FMT defined as the resolution of diarrhea without CDI recurrence. The study included 88 patients: 30 with IBD and 58 without IBD. The IBD group was younger, with fewer comorbidities. Success rates at one month were similar between groups (IBD: 80.0% vs. non-IBD: 78.9%, p = 0.908), as were negative toxin tests (IBD: 83.3% vs. non-IBD: 63.8%, p = 0.174). One-year success rates (IBD: 70.0% vs. non-IBD: 67.6%, p = 0.857) and eradication rates (IBD: 94.4% vs. non-IBD: 73.9%, p = 0.112) were also similar. Poor bowel preparation predicted FMT failure at one month (OR = 0.23, p = 0.019). No safety issues were reported. FMT is a safe, effective treatment for rrCDI, demonstrating similar success rates in patients with and without IBD.

2.
Ultrasound Med Biol ; 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39043483

RESUMO

OBJECTIVE: This paper proposes an ultrasound imaging algorithm based on sub-beamformer and multi-apodization with cross-correlation (SUB-MAX), aiming to achieve high resolution close to the minimum variance (MV) beamforming with low complexity and to enhance image contrast while maintaining background quality. METHODS: The output of two (N/2)-element DAS beamformers with asymmetric phase centers is subtracted, resulting in a large drop in the main-lobe amplitude, while the sidelobe maintains a relatively high amplitude level. Inspired by this characteristic, the coefficients with opposite trends compared with the subtracted output are obtained and fused with the normalized cross-correlation (NCC) weighting matrix acquired by using multi-pair received apodization, the proposed SUB-MAX obtains a new weighting matrix to weight the output of the DAS beamformer. RESULTS: For ats_wire point targets, the average full-width at half-maximum (FWHM) of SUB-MAX compared with DAS, DMAS, CF, and MAX decreases by 52.7%, 43.5%, 33.3%, and 52.7%, respectively. For geabr_0 cysts, the average contrast ratio (CR) of SUB-MAX compared with DAS, MV, DMAS, and CF increases by 57.7%, 86.8%, 2.5%, and 14.4%, respectively. Experiments on rat_tumor dataset also indicate that SUB-MAX has a superior comprehensive imaging performance. CONCLUSION: The experimental results indicate that the superior comprehensive imaging performance of the proposed SUB-MAX is expected to be suitable for real-time imaging systems due to its non-reliance on covariance matrix inversion.

3.
J Geriatr Psychiatry Neurol ; : 8919887241254469, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38757180

RESUMO

BACKGROUND: Neurofilament Light Chain (NfL) is a biomarker of axonal injury elevated in mild cognitive impairment (MCI) and Alzheimer's disease dementia. Blood NfL also inversely correlates with cognitive performance in those conditions. However, few studies have assessed NfL as a biomarker of global cognition in individuals demonstrating mild cognitive deficits who are at risk for vascular-related cognitive decline. OBJECTIVE: To assess the relationship between blood NfL and global cognition in individuals with possible vascular MCI (vMCI) throughout cardiac rehabilitation (CR). Additionally, NfL levels were compared to age/sex-matched cognitively unimpaired (CU) controls. METHOD: Participants with coronary artery disease (vMCI or CU) were recruited at entry to a 24-week CR program. Global cognition was measured using the Montreal Cognitive Assessment (MoCA) and plasma NfL level (pg/ml) was quantified using a highly sensitive enzyme-linked immunosorbent assay. RESULTS: Higher plasma NfL was correlated with worse MoCA scores at baseline (ß = -.352, P = .029) in 43 individuals with vMCI after adjusting for age, sex, and education. An increase in NfL was associated with worse global cognition (b[SE] = -4.81[2.06], P = .023) over time, however baseline NfL did not predict a decline in global cognition. NfL levels did not differ between the vMCI (n = 39) and CU (n = 39) groups (F(1, 76) = 1.37, P = .245). CONCLUSION: Plasma NfL correlates with global cognition at baseline in individuals with vMCI, and is associated with decline in global cognition during CR. Our findings increase understanding of NfL and neurobiological mechanisms associated with cognitive decline in vMCI.

4.
Front Cardiovasc Med ; 11: 1381408, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38646150

RESUMO

Objective: Anticoagulation is crucial for patients hospitalized with coronavirus disease 2019 (COVID-19) due to the high risk of venous thromboembolism (VTE). However, the optimal anticoagulation regimen needs further exploration. Therefore, we evaluated the efficacy and safety of diverse anticoagulation dosage dosages for COVID-19. Methods: An updated meta-analysis was performed to assess the effect of thromboprophylaxis (standard, intermediate, and therapeutic dose) on the incidence of VTE, mortality and major bleeding among COVID-19 patients. Literature was searched via PubMed, EMBASE, Web of Science, and China National Knowledge Infrastructure (CNKI) database. The odds ratio (OR) and 95% confidence interval (CI) were calculated for effect estimates. Results: Nineteen studies involving 25,289 participants without VTE history were included. The mean age of patients was 59.3 years old. About 50.96% were admitted to the intensive care unit. In the pooled analysis, both therapeutic-dose and intermediate-dose anticoagulation did not have a significant advantage in reducing VTE risk over standard dosage (OR = 1.09, 95% CI: 0.58-2.02, and OR = 0.89, 95% CI: 0.70-1.12, respectively). Similarly, all-cause mortality was not further decreased in either therapeutic-dose group (OR = 1.12, 95% CI: 0.75-1.67) or intermediate-dose group (OR = 1.34, 95% CI: 0.83-2.17). While the major bleeding risk was significantly elevated in the therapeutic-dose group (OR = 2.59, 95%CI: 1.87-3.57) as compared with the standard-dose regimen. Compared with intermediate dosage, therapeutic anticoagulation did not reduce consequent VTE risk (OR = 0.85, 95% CI: 0.52-1.38) and all-cause mortality (OR = 0.84, 95% CI: 0.60-1.17), but significantly increased major bleeding rate (OR = 2.42, 95% CI: 1.58-3.70). In subgroup analysis of patients older than 65 years, therapeutic anticoagulation significantly lowered the incidence of VTE in comparation comparison with standard thromboprophylaxis, however, at the cost of elevated risk of major bleeding. Conclusion: Our results indicated that for most hospitalized patients with COVID-19, standard-dose prophylactic anticoagulation might be the optimal choice. For elderly patients at low risk of bleeding, therapeutic-dose anticoagulation could further reduce VTE risk and should be considered especially when there were other strong risk factors of VTE during hospital stay. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO, identifier, CRD42023388429.

5.
BMC Infect Dis ; 24(1): 324, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493138

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19) is frequntly accompanied by venous thromboembolism (VTE), and its mechanism may be related to the abnormal inflammation and immune status of COVID-19 patients. It has been proved that interleukin-6 (IL-6), ferritin and lactate dehydrogenase (LDH) may play an important role in the occurrence of VTE in COVID-19 infection. But whether they can server as predictors for VTE in COVID-19 is still unclear. In this study, we performed a systematic review and meta-analysis to compare IL-6, ferritin and LDH in VTE and non-VTE COVID-19 patients in order to shed light on the prevention and treatment of VTE. METHODS: Related literatures were searched in PubMed, Embase, Web of Science, Google Scholar, China National Knowledge Infrastructure (CNKI), WANGFANG. COVID-19 patients were divided into VTE group and non-VTE group. Meta-analysis was then conducted to compare levels of IL-6, ferritin and LDH between the two groups. RESULTS: We finally included and analyzed 17 literatures from January 2019 to October 2022. There was a total of 7,035 COVID-19 patients, with a weighted mean age of 60.01 years. Males accounted for 62.64% and 61.34% patients were in intensive care unit (ICU). Weighted mean difference (WMD) of IL-6, ferritin and LDH was 31.15 (95% CI: 9.82, 52.49), 257.02 (95% CI: 51.70, 462.33) and 41.79 (95% CI: -19.38, 102.96), respectively. The above results indicated that than compared with non-VTE group, VTE group had significantly higher levels of IL-6 and ferritin but similar LDH. CONCLUSION: This systematic review and meta-analysis pointed out that elevated levels of IL-6 and ferritin were significantly possitive associated with VTE, thus could be used as biological predictive indicators of VTE among COVID-19 patients. However, no association was found between level of LDH and VTE. Therefore, close monitoring of changes in IL-6 and ferritin concentrations is of great value in assisting clinicans to rapidly identify thrombotic complications among COVID-19 patients, hence facilitating the timely effective managment. Further studies are required in terms of the clinical role of cytokines in the occurrence of VTE among COVID-19 infection, with more reliable systematic controls and interventional trials.


Assuntos
COVID-19 , Tromboembolia Venosa , Masculino , Humanos , Pessoa de Meia-Idade , COVID-19/complicações , Interleucina-6 , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/prevenção & controle , Ferritinas , L-Lactato Desidrogenase
6.
Technol Health Care ; 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37840511

RESUMO

BACKGROUND: Beamforming is vital for medical ultrasound imaging systems. The generalized sidelobe canceller (GSC) beamforming can improve the image quality of lateral resolution, but its performance improvement in contrast and robustness is limited. OBJECTIVE: This paper proposes an improved generalized sidelobe canceller algorithm based on multi-apodization with cross-correlation (MAXB-IGSC), which aims to improve the contrast and robustness of ultrasound imaging while maintaining the high image resolution and background speckle quality of GSC. METHODS: The proposed MAXB-IGSC uses multiple pairs of complementary received apodization functions to process the echo data individually to obtain multiple pairs of data sets. The average of their normalized cross-correlation coefficients is then calculated and utilized to determine the adaptive subarray length of the GSC covariance matrix and weights the output of the improved GSC. RESULTS: The MAXB-IGSC improves the contrast ratio (CR) by 171.18% in anechoic cyst simulation and by 91.23%/130.97%/171.76% in geabr_0 (a dataset from the University of Michigan) experiment compared with GSC, respectively. Furthermore, MAXB-IGSC exhibits significant noise immunity, which greatly improves the robustness of the imaging. The technology also maintains the brightness and uniformity of the background speckle. CONCLUSION: The proposed MAXB-IGSC has potential for obtaining high-quality ultrasound images in clinical applications.

7.
ACS Appl Mater Interfaces ; 15(38): 45106-45115, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37699573

RESUMO

Gesture recognition systems epitomize a modern and intelligent approach to rehabilitative training, finding utility in assisted driving, sign language comprehension, and machine control. However, wearable devices that can monitor and motivate physically rehabilitated people in real time remain little studied. Here, we present an innovative gesture recognition system that integrates hydrogel strain sensors with machine learning to facilitate finger rehabilitation training. PSTG (PAM/SA/TG) hydrogels are constructed by thermal polymerization of acrylamide (AM), sodium alginate (SA), and tannic acid-reduced graphene oxide (TA-rGO, TG), with AM polymerizing into polyacrylamide (PAM). The surface of TG has abundant functional groups that can establish multiple hydrogen bonds with PAM and SA chains to endow the hydrogel with high stretchability and mechanical stability. Our strain sensor boasts impressive sensitivity (Gauge factor = 6.13), a fast response time (40.5 ms), and high linearity (R2 = 0.999), making it an effective tool for monitoring human joint movements and pronunciation. Leveraging machine learning techniques, our gesture recognition system accurately discerns nine distinct types of gestures with a recognition accuracy of 100%. Our research drives wearable advancements, elevating the landscape of patient rehabilitation and augmenting gesture recognition systems' healthcare applications.

8.
Ultrasonics ; 134: 107084, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37352574

RESUMO

In this paper, an ultrasound imaging method combined with low-complexity adaptive beamformer (LCA) and improved multiphase apodization with cross-correlation (IMPAX) is proposed to improve image resolution and contrast with low hardware cost. Firstly, the delayed echo signal is apodized by the LCA to obtain a narrow mainlobe width echo signal and LCA output. Then, multiple pairs of complementary square-wave phase apodizations are applied to the apodized echo signal to obtain corresponding signal pairs, which are used to calculate the normalized cross-correlation (NCC) matrix. Finally, the average value of the NCC matrices is filtered by 2-D means, and the filtered result is introduced as the weighting factor for the LCA output. The simulation and experimental results show that the proposed LCA-IMPAX can effectively reduce the mainlobe width, suppress clutter, and be robust to noise. Compared with DAS, LCA, and MPAX, for simulated point targets, the full-width at half-maximum (FWHM, -6dB) of LCA-IMPAX is reduced by 49.22%, 10.06%, and 48.67%, respectively. For simulated cyst, the CR is improved by 219.91%, 138.08%, and 103.44%, respectively. For experimental cysts, the CR is improved by an average of 145.00%, 136.14%, and 55.09%, respectively. The results of human heart data indicate that LCA-IMPAX has good imaging quality in vivo. Since the proposed method does not involve covariance matrix inversion, it can be applied in real-time imaging systems.

9.
Alzheimers Res Ther ; 14(1): 23, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-35123548

RESUMO

BACKGROUND: Increasing evidence implicates oxidative stress (OS) in Alzheimer disease (AD) and mild cognitive impairment (MCI). Depletion of the brain antioxidant glutathione (GSH) may be important in OS-mediated neurodegeneration, though studies of post-mortem brain GSH changes in AD have been inconclusive. Recent in vivo measurements of the brain and blood GSH may shed light on GSH changes earlier in the disease. AIM: To quantitatively review in vivo GSH in AD and MCI compared to healthy controls (HC) using meta-analyses. METHOD: Studies with in vivo brain or blood GSH levels in MCI or AD with a HC group were identified using MEDLINE, PsychInfo, and Embase (1947-June 2020). Standardized mean differences (SMD) and 95% confidence intervals (CI) were calculated for outcomes using random effects models. Outcome measures included brain GSH (Meshcher-Garwood Point Resolved Spectroscopy (MEGA-PRESS) versus non-MEGA-PRESS) and blood GSH (intracellular versus extracellular) in AD and MCI. The Q statistic and Egger's test were used to assess heterogeneity and risk of publication bias, respectively. RESULTS: For brain GSH, 4 AD (AD=135, HC=223) and 4 MCI (MCI=213, HC=211) studies were included. For blood GSH, 26 AD (AD=1203, HC=1135) and 7 MCI (MCI=434, HC=408) studies were included. Brain GSH overall did not differ in AD or MCI compared to HC; however, the subgroup of studies using MEGA-PRESS reported lower brain GSH in AD (SMD [95%CI] -1.45 [-1.83, -1.06], p<0.001) and MCI (-1.15 [-1.71, -0.59], z=4.0, p<0.001). AD had lower intracellular and extracellular blood GSH overall (-0.87 [-1. 30, -0.44], z=3.96, p<0.001). In a subgroup analysis, intracellular GSH was lower in MCI (-0.66 [-1.11, -0.21], p=0.025). Heterogeneity was observed throughout (I2 >85%) and not fully accounted by subgroup analysis. Egger's test indicated risk of publication bias. CONCLUSION: Blood intracellular GSH decrease is seen in MCI, while both intra- and extracellular decreases were seen in AD. Brain GSH is decreased in AD and MCI in subgroup analysis. Potential bias and heterogeneity suggest the need for measurement standardization and additional studies to explore sources of heterogeneity.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doença de Alzheimer/psicologia , Encéfalo/metabolismo , Disfunção Cognitiva/psicologia , Glutationa/metabolismo , Humanos , Estresse Oxidativo
10.
Bioresour Technol ; 341: 125822, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34467889

RESUMO

This study discovered one nitrate-calcium-based anammox start-up pathway. Compared with control, the start-up time of anammox was saved by 33.3%, and the average total nitrogen removal efficiency increased from 29.6% to 53.7% during the start-up. Besides, the continuous nitrite accumulation (1.18 mg/L) and a marked increase in the relative abundance of denitrifying and anammox bacteria were observed in the only Ca(NO3)2-added group. These results suggested that calcium nitrate induced partial denitrification to provide nitrite for anammox. Additionally, the role of dissimilatory nitrate reduction to ammonium (DNRA) in the Ca(NO3)2-added systems also deserved attention, for the contribution of DNRA to nitrate removal as well as the relative abundance of DNRA bacteria were both increased for the Ca(NO3)2-added groups. These results suggested that a mutualistic symbiosis among denitrification, DNRA and anammox exists in the calcium nitrate-added systems, which may explain the reason for acceleration of anammox start-up by adding calcium nitrate.


Assuntos
Compostos de Amônio , Anaerobiose , Compostos de Cálcio , Desnitrificação , Nitratos , Nitrogênio , Oxirredução
11.
J Alzheimers Dis ; 79(3): 1285-1296, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33427735

RESUMO

BACKGROUND: Coronary artery disease (CAD) increases risk for vascular cognitive impairment-no dementia (VCIND), a precursor to dementia, potentially through persistent oxidative stress. OBJECTIVE: This study assessed peripheral glutathione peroxidase activity (GPX), which is protective against oxidative stress, in VCIND versus cognitively normal CAD controls (CN). GPX activity was also evaluated as a biomarker of cognition, particularly verbal memory. METHODS: 120 CAD patients with VCIND (1SD below norms on executive function or verbal memory (VM)) or without (CN) participated in exercise rehabilitation for 24 weeks. Neurocognitive and cardiopulmonary fitness (VO2peak) assessments and plasma were collected at baseline and 24-weeks. RESULTS: GPX was higher in VCIND compared to CN (F1,119 = 3.996, p = 0.048). Higher GPX was associated with poorer baseline VM (ß= -0.182, p = 0.048), and longitudinally with VM decline controlling for sex, body mass index, VO2peak, and education (b[SE] = -0.02[0.01], p = 0.004). Only CN participants showed improved VM performance with increased fitness (b[SE] = 1.30[0.15], p < 0.005). CONCLUSION: GPX was elevated in VCIND consistent with a compensatory response to persistent oxidative stress. Increased GPX predicted poorer cognitive outcomes (verbal memory) in VCIND patients despite improved fitness.


Assuntos
Transtornos Cerebrovasculares/enzimologia , Disfunção Cognitiva/enzimologia , Glutationa Peroxidase/metabolismo , Rememoração Mental , Aprendizagem Verbal , Biomarcadores , Transtornos Cerebrovasculares/sangue , Disfunção Cognitiva/sangue , Função Executiva , Feminino , Glutationa Peroxidase/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estresse Oxidativo
12.
Microb Ecol ; 81(2): 314-322, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32935184

RESUMO

In this study, the joint use of high throughput sequencing, real-time quantitative PCR, and ammonia-oxidizing bacteria (AOB)-inhibiting allylthiourea was used to differentiate between the contributions of ammonia-oxidizing archaea (AOA) vs AOB to ammonia oxidation and ascertain how AOA and AOB responded to two widely used river remediation techniques (aeration and Ca(NO3)2 injection). Results showed that ammonia oxidation was largely attributed to ATU-sensitive AOB rather than AOA and Nitrosomonas was the predominant AOB-related genus (53.86%) in the malodorous river. The contribution of AOB to ammonia oxidation in the context of aeration and Ca(NO3)2 injection was 75.51 ± 2.77% and 60.19 ± 10.44%, respectively. The peak of AOB/AOA ratio and the marked increase of relative abundances of Nitrosomonas and Nitrosospira in aeration runs further demonstrated aeration favored the ammonia oxidation of AOB. Comparatively, Ca(NO3)2 injection could increase the ammonia oxidation contribution of AOA from 31.32 ± 6.06 to 39.81 ± 10.44% and was significantly correlated with Nitrosococcus of AOB (r = 0.796, p < 0.05), Candidatus_Nitrosopelagicus of AOA (r = 0.986, p < 0.01), and AOA Simpson diversity (r = - 0.791, p < 0.05). Moreover, Candidatus_Nitrosopelagicus was only present in Ca(NO3)2 runs. Taken together, Ca(NO3)2 was recognized as an important factor in mediating the growth and ecological niches of ammonia oxidizers.Graphical abstract.


Assuntos
Amônia/metabolismo , Archaea/metabolismo , Bactérias/metabolismo , Recuperação e Remediação Ambiental/métodos , Sedimentos Geológicos/microbiologia , Rios/microbiologia , Amônia/análise , Archaea/classificação , Archaea/genética , Archaea/isolamento & purificação , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Compostos de Cálcio/análise , Sedimentos Geológicos/química , Nitratos/análise , Oxirredução , Oxigênio/análise , Rios/química , Especificidade da Espécie , Poluentes Químicos da Água/metabolismo
13.
Dev Neuropsychol ; 45(2): 66-78, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32063038

RESUMO

In contrast to reactive inhibition, intentional inhibition is the internally generated decision to "stop" without any external signals. Whether adults and adolescents' neural correlates on these two inhibitions have any differences is still unknown. We measured 20 adults and 21 adolescents' ERP-related N2 using a free-choice Go/Nogo task. The results of the adult's group showed that the mean amplitude and peak latency of intentional Nogo-N2 did not differ from the reactive Nogo-N2. In contrast, the mean amplitude and peak latency for reactive Nogo-N2 in the adolescent group was significantly greater than what was observed for the intentional Nogo-N2. Comparison across groups revealed that the mean amplitude and peak latency of reactive Nogo-N2 were significantly greater in adolescents than in adults, while intentional Nogo-N2 did not differ between groups. These findings may indicate that adolescents lack of self-control is more reflected in reactive inhibition, if adolescents decide whether to do, they will be as good as adults.


Assuntos
Eletroencefalografia/métodos , Inibição Psicológica , Inibição Reativa , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
14.
Talanta ; 208: 120404, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31816771

RESUMO

A novel area controllable biosensing interface is designed on glassy carbon bead (GCB) and used for measurement of tetracycline (TET) in closed bipolar electrode-electrochemiluminescence (ECL) device. One face of GCB is modified with Au particles and the covered area is varied from 0 to 45.3% by tuning the external voltage during bipolar electrodeposition process in a home-made open bipolar electrochemical cell. It enables the conjugation of various amounts of biomolecules on Au/GCB. Then DNA walker and methylene blue (MB) labeled DNA (MB-DNA) are conjugated on Au surface for the following combination of aptamer. In the presence of target, aptamer partially hybridized with DNA walker will be released from Au surface, leading to the formation of dsDNA between DNA walker and MB-DNA. As a result, MB-DNA with recognition site for nicking endonuclease (Nb.BbvCI) in dsDNA is cleft into two segments by Nb.BbvCI. Meanwhile, the liberated DNA walker is triggered to continue the degradation of many MB-DNA. Due to the excellent electrochemical performance of MB, it is reduced at the cathode of BPE to amplify the ECL signal at the anode of BPE in a closed BPE-ECL platform. When the covered area of GCB by Au particles is enlarged from 10.1 to 45.3%, the change of ECL intensity could be increased 2.7-fold. The linear range for the detection of tetracycline is from 1 × 10-12 to 1 × 10-5 M with the detection limit of 6.0 × 10-13 M. Hence, controllable sensing area on a single glassy carbon bead, the amplification effect of DNA walker and MB make this approach possess many advantages over traditional biosensor.


Assuntos
Eletroquímica/instrumentação , Medições Luminescentes/instrumentação , Tetraciclina/análise , Animais , Calibragem , Eletrodos , Leite/química , Propriedades de Superfície , Tetraciclina/química
15.
World J Microbiol Biotechnol ; 35(12): 196, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31784839

RESUMO

In this research, the dynamics of nitrogen transformation and bacterial community in malodorous river were investigated with different aeration depths. Computational flow dynamics (CFD) and Reynolds number (Re) were specially used to characterize the hydrodynamics condition under different aeration depths. The results indicated that aeration depth had vital impact on nitrogen transformation and bacterial community structure. It was found that a range of aeration depth (0.20-0.45 m above sediment-water interface) facilitated the removal of NH4+-N and TN with Re ranging between 6211 and 8930. Proteobacteria took over Firmicutes to become the predominant phylum (36-78%) under aeration, and the main subdivisions of γ-, ß- and δ-Proteobacteria also varied greatly with different aeration depths. Interestingly, there was a marked shift of the inferentially identified dominant functional role within Proteobacteria from organic-matter degradation to nitrogen metabolism and then to sulfur metabolism as well as the coupling of nitrogen and sulfur with the increase of disturbance. The redundancy analysis (RDA) further confirmed the importance of aeration disturbance in shaping bacterial community. These findings help to gain improved understanding of endogenous N-behavior and aquatic microbial ecology, and underline the need for integrating the hydrodynamics factors with microbial community.


Assuntos
Bactérias/metabolismo , Microbiota/fisiologia , Nitrogênio/metabolismo , Rios/química , Rios/microbiologia , Bactérias/classificação , Bactérias/genética , China , Sedimentos Geológicos/microbiologia , Oxigênio/metabolismo , Filogenia , RNA Ribossômico 16S , Enxofre/metabolismo
16.
Cell Reprogram ; 21(6): 323-330, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31730378

RESUMO

Myocardial diseases usually appear ischemic. Reperfusion therapy is one of the effective methods that can improve clinical therapeutic efficacy. However, reperfusion results in myocardial injury named I/R injury. Rosuvastatin (RS) is HMG-CoA reductase inhibitor. We investigated the role of RS in the myocardial I/R injury in vitro and its active mechanism. Oxygen-glucose deprivation/reoxygenation (OGD/R) model was applied to investigate I/R in vitro. OGD/R decreased cell viability and increased levels of miR-17-3p and lactate dehydrogenase (LDH) leakage. Besides, RS decreased cleaved caspase-3 level and LDH leakage, promoted the levels of miR-17-3p and LC3II/LC3I, and increased cell viability when H9C2 cell was treated by OGD/R. miR-17-3p inhibitor reduced the H9C2 cell viability and LC3II/LC3I level, whereas miR-17-3p mimics increased H9C2 cell viability and LC3II/LC3I level. RS promoted cell viability and increased LC3II/LC3I level while it lowered LDH leakage, apoptosis rate, and the levels of cleaved caspase-3 and Cyto c. Our study suggested that RS reduced I/R injury in cardiocyte via cleaved caspase-3/Cyto c apoptosis signaling pathway and autophagy. Moreover, the autophagy happens to cardiocyte by upregulating the expression of miR-17-3p.


Assuntos
Autofagia/efeitos dos fármacos , MicroRNAs/biossíntese , Modelos Cardiovasculares , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Miócitos Cardíacos/metabolismo , Rosuvastatina Cálcica/farmacologia , Regulação para Cima/efeitos dos fármacos , Linhagem Celular , Humanos , Proteínas Musculares/biossíntese , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miócitos Cardíacos/patologia
17.
Analyst ; 144(15): 4633-4638, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31250857

RESUMO

A novel electrochemiluminescence (ECL) closed bipolar electrode (BPE) chip was designed based on a hybridization chain reaction (HCR)-induced ECL amplification strategy for the detection of both DNA and H2O2. Without the utilization of a patterned ITO bipolar electrode (BPE), this chip platform consisted of an ITO glass coated with two layers of PDMS slices. The ITO cathode was modified with Au nanoparticles for further functionalization of biomolecules, which could also amplify the ECL signal at the anode of the BPE. Based on the specific hybridization and hybridization chain reaction (HCR), DNA sequences were greatly extended, leading to a significant increase in the resistance of the cathode. The reduction of H2O2 was inhibited on the cathode of the BPE, resulting in a quenching effect on the ECL intensity on the anode of the BPE. The designed biosensor displayed a satisfactory linear relationship for the detection of both DNA and H2O2. Therefore, the biosensor could not only be employed for DNA assays but also used in enzyme reactions based on the generation of H2O2.


Assuntos
DNA/análise , Peróxido de Hidrogênio/análise , Técnicas Biossensoriais/métodos , DNA/genética , Sondas de DNA/química , Sondas de DNA/genética , Dimetilpolisiloxanos/química , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos , Ouro/química , Peróxido de Hidrogênio/química , Sequências Repetidas Invertidas , Medições Luminescentes/métodos , Nanopartículas Metálicas/química , Hibridização de Ácido Nucleico , Oxirredução , Compostos de Estanho/química
18.
Calcif Tissue Int ; 104(2): 182-192, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30302533

RESUMO

Duchenne muscular dystrophy (DMD) is an X-linked disease of progressive muscle deterioration and weakness. Patients with DMD have poor bone health which is partly due to treatment with glucocorticoids, a standard therapy to prolong muscle function that also induces bone loss. Bisphosphonates are used to treat adults at risk of glucocorticoid-induced osteoporosis but are not currently used in DMD patients until after they sustain fractures. In this study, C57BL/10ScSn-mdx mice, a commonly used DMD animal model, received continuous glucocorticoid, prednisone treatment (0.083 mg/day) from 5 to 10 weeks of age. Pre-treatment with the bisphosphonate pamidronate started at 4 weeks of age over a period of 2 weeks or 6 weeks (cumulative dose 8 mg/kg for both) to assess the effectiveness of the two dosing regimens in ameliorating glucocorticoid-induced bone loss. Mdx mice treated with prednisone had improved muscle function that was not changed by pamidronate treatment. Glucocorticoid treatment caused cortical bone loss and decreased cortical bone strength. Both 2 and 6 week pamidronate treatment increased cortical thickness and bone area compared to prednisone-treated Mdx mice, however, only 2 week pamidronate treatment improved the strength of cortical bone compared to that of glucocorticoid-treated Mdx mice. In the trabecular bone, both pamidronate treatments significantly increased the amount of bone, and increased the ultimate load but not the energy to fail. These results highlight the importance of when and how much bisphosphonate is administered prior to glucocorticoid exposure.


Assuntos
Fenômenos Biomecânicos/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Glucocorticoides/uso terapêutico , Distrofia Muscular de Duchenne/tratamento farmacológico , Pamidronato/administração & dosagem , Animais , Doenças Ósseas Metabólicas/induzido quimicamente , Doenças Ósseas Metabólicas/prevenção & controle , Osso e Ossos/fisiologia , Osso Esponjoso/efeitos dos fármacos , Osso Cortical/efeitos dos fármacos , Modelos Animais de Doenças , Esquema de Medicação , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos mdx , Camundongos Transgênicos , Força Muscular/efeitos dos fármacos , Força Muscular/fisiologia , Distrofia Muscular de Duchenne/patologia
19.
Chemistry ; 23(23): 5565-5572, 2017 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-28272786

RESUMO

The first heterobimetallic phosphide thin film containing iron, manganese, and phosphorus, derived from the single-source precursor FeMn(CO)8 (µ-PH2 ), has been prepared using a home-built metal-organic chemical vapor deposition apparatus. The thin film contains the same ratio of iron, manganese, and phosphorus as the initial precursor. The film becomes oxidized when deposited on a quartz substrate, whereas the film deposited on an alumina substrate provides a more homogeneous product. Powder X-ray diffraction confirms the formation of a metastable, hexagonal FeMnP phase that was previously only observed at temperatures above 1200 °C. Selected area electron diffraction on single crystals isolated from the films was indexed to the hexagonal phase. The effective moment of the films (µeff =3.68 µB ) matches the previously reported theoretical value for the metastable hexagonal phase, whereas the more stable orthorhombic phase is known to be antiferromagnetic. These results not only demonstrate the successful synthesis of a bimetallic, ternary thin film from a single-source precursor, but also the first low temperature approach to the hexagonal phase of FeMnP.

20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(2): 391-3, 2017 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-30264967

RESUMO

Owing to its merits of high corrosion resistance, high temperature stability as well as good mechanical strength etc., silicon nitride membrane (SiN) has been widely used as the experimental carrier of transmission electron microscope (TEM), scanning electron microscopy (SEM), atomic force microscope (AFM), X-ray photoelectron spectroscopy (XPS), energy dispersive X-Ray spectroscopy (EDX) and other characterization. In particular, SiN can be used as a low disturbing background for SEM observation. However, the poor luminescent property of SiN thin film has restricted its wide application in fluorescent devices. In order to enhance the fluorescence efficiency of silicon nitride membrane, a series of ZnO films were prepared on a SiNx film substrate with radio frequency magnetron sputtering (RF magnetron sputtering) technology during the experiment. Samples were then non-situ and in-situ annealed in nitrogen atmosphere, respectively. Then, atomic force microscope (AFM), scanning electron microscopy (SEM) and Raman spectroscopy (Raman) were applied to study the microstructure and photoluminescence (PL) properties of the prepared films. This paper also systemically studies the luminescence of the prepared thin films. The results show that, luminescent intensity increases after sputtering, while annealing further promoted the grain growth, a substantial increase in crystallization behavior and a decrease in grain boundary. The microstructure and luminescence properties of ZnO/SiN thin films prepared by RF magnetron sputtering were significantly influenced by annealing method. Compared with the SiNx film, near the band edge of the intrinsic emission intensity (about 380 nm) of untempered ZnO/SiNx films and N(2) atmosphere ex-situ annealed ZnO/SiNx films were increased by more than 7.7 times and 34.0 times. Compared with non-situ annealed films, in-situ annealed films contained more oxygen vacancy defects, thus showing a stronger visible light PL intensity. In-situ annealed films exhibited a higher photoluminescence capacity during the wavelength from 425 to 600 nm of visible light. These results can help to optimize the preparation parameters of silicon nitride based ZnO fluorescent films.

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