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1.
Waste Manag ; 135: 389-396, 2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34610538

RESUMO

In this study, a novel method for producing direct reduced iron (DRI) powders based on microwave-assisted self-reduction of core-shell composite pellets composed of blast furnace (BF) dust and hazardous electric arc furnace (EAF) dust followed by magnetic separation was reported. The proper core-shell structure of the composite pellets was designed according to the rule of impedance matching and properties of BF dust and EAF dust by adjusting the thickness of shell (i.e., thickness of impedance matching layer) via controlling the C/O molar ratio of the raw materials from 0.55 to 0.70. The results showed that the EAF dust with high content of CaO was beneficial to the mechanical strength of green, dried, and metallized pellets (collected after reduction), while the BF dust with high content of carbon enabled sufficient microwave-assisted reduction of the pellets, facilitating subsequent magnetic separation and also the removal of zinc from EAF dust. By reduction of the core-shell BF dust-EAF dust composite pellets with the C/O molar ratio of 0.65 at 1050 °C for 15 min, the resulting metallized pellets showed superior reduction and magnetic separation indexes with higher removal percentages of zinc and lead, in comparison with conventional metallized pellets. The DRI powders obtained after magnetic separation had total iron content of 91.2 wt%, iron metallization degree of 95.8%, yield of 68.1%, and iron recovery of 88.0%. This study provided a good example for efficient and environmentally friendly comprehensive utilization of typical and hazardous wastes in the iron and steel industry.

2.
Theranostics ; 11(19): 9243-9261, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34646369

RESUMO

The coagulation protein tissue factor (TF) regulates inflammation and angiogenesis via its cytoplasmic domain in infection, cancer and diabetes. While TF is highly abundant in the heart and is implicated in cardiac pathology, the contribution of its cytoplasmic domain to post-infarct myocardial injury and adverse left ventricular (LV) remodeling remains unknown. Methods: Myocardial infarction was induced in wild-type mice or mice lacking the TF cytoplasmic domain (TF∆CT) by occlusion of the left anterior descending coronary artery. Heart function was monitored with echocardiography. Heart tissue was collected at different time-points for histological, molecular and flow cytometry analysis. Results: Compared with wild-type mice, TF∆CT had a higher survival rate during a 28-day follow-up after myocardial infarction. Among surviving mice, TF∆CT mice had better cardiac function and less LV remodeling than wild-type mice. The overall improvement of post-infarct cardiac performance in TF∆CT mice, as revealed by speckle-tracking strain analysis, was attributed to reduced myocardial deformation in the peri-infarct region. Histological analysis demonstrated that TF∆CT hearts had in the infarct area greater proliferation of myofibroblasts and better scar formation. Compared with wild-type hearts, infarcted TF∆CT hearts showed less infiltration of proinflammatory cells with concomitant lower expression of protease-activated receptor-1 (PAR1) - Rac1 axis. In particular, infarcted TF∆CT hearts displayed markedly lower ratios of inflammatory M1 macrophages and reparative M2 macrophages (M1/M2). In vitro experiment with primary macrophages demonstrated that deletion of the TF cytoplasmic domain inhibited macrophage polarization toward the M1 phenotype. Furthermore, infarcted TF∆CT hearts presented markedly higher peri-infarct vessel density associated with enhanced endothelial cell proliferation and higher expression of PAR2 and PAR2-associated pro-angiogenic pathway factors. Finally, the overall cardioprotective effects observed in TF∆CT mice could be abolished by subcutaneously infusing a cocktail of PAR1-activating peptide and PAR2-inhibiting peptide via osmotic minipumps. Conclusions: Our findings demonstrate that the TF cytoplasmic domain exacerbates post-infarct cardiac injury and adverse LV remodeling via differential regulation of inflammation and angiogenesis. Targeted inhibition of the TF cytoplasmic domain-mediated intracellular signaling may ameliorate post-infarct LV remodeling without perturbing coagulation.

3.
Mod Pathol ; 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34593968

RESUMO

A novel 3-tiered grading system based on tumor budding activity and cell nest size has been validated to be highly prognostic in organ-wide squamous cell carcinomas. In this study, we applied a similar grading system with slight modification to assess the prognostic value in an institutional cohort of well annotated endocervical adenocarcinomas (EAC) consisting of 398 consecutive cases with surgical resection, no neoadjuvant chemotherapy, and higher than stage pT1a. Each case was reviewed by the International Endocervical Adenocarcinoma Criteria and Classification (IECC) and Silva pattern classification, and scored on tumor budding activity and cell cluster size to form the basis of a novel grading system. High budding activity, small tumor cell cluster size, and novel grade 3 were more frequently associated with a decreased overall survival time and tumor recurrence time (p < 0.001), and several other clinicopathologic factors including HPV-independent adenocarcinoma, lymphovascular invasion, lymph node metastasis, advanced FIGO stage, and Silva pattern C (p < 0.05). Moreover, the novel grading system was helpful in stratifying overall survival in HPV-associated adenocarcinoma (p = 0.036) and gastric-type adenocarcinoma (p = 0.033). On multivariate analysis, novel grade 3 was an adverse indicator for overall survival and tumor recurrence independently of age and FIGO stage (p < 0.05). By comparison, Silva pattern C was only associated with tumor relapse (p = 0.020) in HPV-associated adenocarcinomas whereas the conventional FIGO system was not associated with overall survival and tumor recurrence in EAC (p > 0.05). In conclusion, our study demonstrates that the grading system based on tumor budding activity and cell cluster size is robust in prognostic assessment that outperforms the conventional FIGO grading and Silva pattern classification in EAC. The novel grading system, if further validated, could be applicable in routine pathologic descriptions of EAC by providing useful information in clinical decision-making.

4.
Dalton Trans ; 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34528985

RESUMO

Since the large reaction energy barrier caused by multi-step electron transfer processes of the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) gravely restricts the practical application of electrocatalytic water splitting, it is urgent to develop a dual-functional electrocatalyst which can effectively reduce the reaction energy barrier and actually speed up the reaction. Herein, the Ru species are doped into the complex of magnetite and FeNi-layered double hydroxide by a one-step oil bath method, and a self-supporting binder-free bifunctional electrocatalyst was synthesized on the surface of iron foam (named Ru-Fe3O4@FeNi-LDH/IF). The unique 3D core-shell microflower structure of Ru-Fe3O4@FeNi-LDH/IF, the combination of active ingredient and conductive substrate, together with the doping of Ru may immensely provide a large number of active sites, adjust the electronic structure, accelerate electron transfer, and thus greatly improve the electrocatalytic activity and durability. It is worth mentioning that when Ru-Fe3O4@FeNi-LDH/IF is used as the anode and cathode for overall water splitting, only 1.52 V battery voltage can generate a current density of 10 mA cm-2, and also maintain a prominent stability for at least 36 hours. This work provides a feasible strategy for heteroatom-doping LDH as a bifunctional electrocatalyst.

6.
Biomed Res Int ; 2021: 6618257, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34497852

RESUMO

Background: This study is aimed at investigating whether dapagliflozin adjunct to insulin therapy further improves glycemic control compared to insulin therapy alone in patients with newly diagnosed type 2 diabetes (T2D). Methods: This single-centre, randomized, controlled, open-labeled trial recruited newly diagnosed T2D patients. Subjects were randomized 1 : 1 to the dapagliflozin add-on to continuous subcutaneous insulin infusion (CSII) group (DAPA) or the CSII therapy group for 5 weeks. Standard meal tests were performed 3 times at days -3, 7, and 35 for glucose, C-peptide, and insulin level determination. Two-time continuous glucose monitoring (CGM) was performed at baseline and at the end of the study. The primary endpoint was the difference in the mean amplitude of glycemic excursions (MAGEs) between the groups. Results: A total of 66 subjects completed the study, with 34 and 32 patients in the DAPA and CSII groups, respectively. Patients in the DAPA group exhibited significant decreases in MAGE levels at the endpoint. We also observed that patients in the DAPA group had a lower homoeostasis model assessment insulin resistance (HOMA-IR) and a higher homoeostasis model assessment B (HOMA-B) value at 1 week and 5 weeks compared to those with insulin therapy, respectively. In addition, our data showed that patients in the DAPA group showed a significantly lower insulin dose (0.07 U/kg) and weighed less than those in the CSII group. Conclusion: Our data indicate that dapagliflozin adjunct to insulin is a safe and effective therapy for improving glycemic variations, insulin sensitivity, and weight loss in newly diagnosed T2D patients.


Assuntos
Compostos Benzidrílicos/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucosídeos/uso terapêutico , Insulina/uso terapêutico , Compostos Benzidrílicos/efeitos adversos , Glicemia/metabolismo , Peptídeo C/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/patologia , Combinação de Medicamentos , Feminino , Glucosídeos/efeitos adversos , Hemoglobina A Glicada/metabolismo , Humanos , Hipoglicemiantes/uso terapêutico , Infusões Subcutâneas/métodos , Masculino , Pessoa de Meia-Idade , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico
7.
Front Cell Infect Microbiol ; 11: 590989, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34513721

RESUMO

Clustered regularly interspaced short palindromic repeats (CRISPR) systems are a set of versatile gene-editing toolkit that perform diverse revolutionary functions in various fields of application such as agricultural practices, food industry, biotechnology, biomedicine, and clinical research. Specially, as a novel antiviral method of choice, CRISPR/Cas9 system has been extensively and effectively exploited to fight against human infectious viruses. Infectious diseases including human immunodeficiency virus (HIV), hepatitis B virus (HBV), human papillomavirus (HPV), and other viruses are still global threats with persistent potential to probably cause pandemics. To facilitate virus removals, the CRISPR/Cas9 system has already been customized to confer new antiviral capabilities into host animals either by modifying host genome or by directly targeting viral inherent factors in the form of DNA. Although several limitations and difficulties still need to be conquered, this technology holds great promises in the treatment of human viral infectious diseases. In this review, we will first present a brief biological feature of CRISPR/Cas9 systems, which includes a description of CRISPR/Cas9 structure and composition; thereafter, we will focus on the investigations and applications that employ CRISPR/Cas9 system to combat several human infectious viruses and discuss challenges and future perspectives of using this new platform in the preclinical and clinical settings as an antiviral strategy.

8.
J Zhejiang Univ Sci B ; 22(8): 664-681, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34414701

RESUMO

Copy number variations (CNVs), which can affect the role of long non-coding RNAs (lncRNAs), are important genetic changes seen in some malignant tumors. We analyzed lncRNAs with CNV to explore the relationship between lncRNAs and prognosis in bladder cancer (BLCA). Messenger RNA (mRNA) expression levels, DNA methylation, and DNA copy number data of 408 BLCA patients were subjected to integrative bioinformatics analysis. Cluster analysis was performed to obtain different subtypes and differently expressed lncRNAs and coding genes. Weighted gene co-expression network analysis (WGCNA) was performed to identify the co-expression gene and lncRNA modules. CNV-associated lncRNA data and their influence on cancer prognosis were assessed with Kaplan-Meier survival curve. Multi-omics integration analysis revealed five prognostic lncRNAs with CNV, namely NR2F1-AS1, LINC01138, THUMPD3-AS1, LOC101928489,and TMEM147-AS1,and a risk-score signature related to overall survival in BLCA was identified. Moreover, validated results in another independent Gene Expression Omnibus (GEO) dataset, GSE31684, were consistent with these results. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that the mitogen-activated protein kinase (MAPK) signaling pathway, focal adhesion pathway, and Janus kinase-signal transducers and activators of transcription (JAK-STAT) signaling pathway were enriched in a high-risk score pattern, suggesting that imbalance in these pathways is closely related to tumor development. We revealed the prognosis-related lncRNAs by analyzing the expression profiles of lncRNAs and CNVs, which can be used as prognostic biomarkers for BLCA.

9.
J Phys Chem Lett ; 12(34): 8440-8446, 2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34436908

RESUMO

Hybrid heterostructures comprising organic and two-dimensional (2D) layered semiconductors hold great promise for light harvesting and optoelectronic applications. Among them, organic materials that exhibit singlet fission (SF) in which one singlet exciton generates two triplet excitons are particularly attractive and can potentially improve the performance of the device. However, SF-enhanced devices require that SF can compete with direct energy/charge transfer from the singlet exciton. Here, we performed ultrafast spectroscopic studies on a prototypical heterostructure consisting of tetracene (Tc) and monolayer WSe2. We show a type II band alignment with 16.5 ps hole transfer from photoexcited WSe2 to tetracene and a long-lived (∼565 ps) charge separation. Importantly, we show ultrafast (∼3.4 ps) singlet exciton energy transfer from photoexcited tetracene to WSe2, prior to the slow SF process (>20 ps) in tetracene. This study raises the challenge and calls for the careful design of SF-enhanced 2D optoelectronic devices.

11.
Theranostics ; 11(16): 7879-7895, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335970

RESUMO

Rationale: Previous studies have shown that human embryonic stem cell-derived cardiomyocytes improved myocardial recovery when administered to infarcted pig and non-human primate hearts. However, the engraftment of intramyocardially delivered cells is poor and the effectiveness of clinically relevant doses of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) in large animal models of myocardial injury remains unknown. Here, we determined whether thymosin ß4 (Tb4) could improve the engraftment and reparative potency of transplanted hiPSC-CMs in a porcine model of myocardial infarction (MI). Methods: Tb4 was delivered from injected gelatin microspheres, which extended the duration of Tb4 administration for up to two weeks in vitro. After MI induction, pigs were randomly distributed into 4 treatment groups: the MI Group was injected with basal medium; the Tb4 Group received gelatin microspheres carrying Tb4; the CM Group was treated with 1.2 × 108 hiPSC-CMs; and the Tb4+CM Group received both the Tb4 microspheres and hiPSC-CMs. Myocardial recovery was assessed by cardiac magnetic resonance imaging (MRI), arrhythmogenesis was monitored with implanted loop recorders, and tumorigenesis was evaluated via whole-body MRI. Results: In vitro, 600 ng/mL of Tb4 protected cultured hiPSC-CMs from hypoxic damage by upregulating AKT activity and BcL-XL and promoted hiPSC-CM and hiPSC-EC proliferation. In infarcted pig hearts, hiPSC-CM transplantation alone had a minimal effect on myocardial recovery, but co-treatment with Tb4 significantly enhanced hiPSC-CM engraftment, induced vasculogenesis and the proliferation of cardiomyocytes and endothelial cells, improved left ventricular systolic function, and reduced infarct size. hiPSC-CM implantation did not increase incidence of ventricular arrhythmia and did not induce tumorigenesis in the immunosuppressed pigs. Conclusions: Co-treatment with Tb4-microspheres and hiPSC-CMs was safe and enhanced the reparative potency of hiPSC-CMs for myocardial repair in a large-animal model of MI.


Assuntos
Infarto do Miocárdio/terapia , Miócitos Cardíacos/metabolismo , Timosina/farmacologia , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , China , Modelos Animais de Doenças , Células Endoteliais/patologia , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Infarto do Miocárdio/metabolismo , Miocárdio/patologia , Regeneração , Transplante de Células-Tronco/métodos , Suínos , Timosina/metabolismo , Timosina/fisiologia
12.
Methods Mol Biol ; 2359: 43-51, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34410658

RESUMO

Molecularly imprinted polymers have been studied for a long time and have found useful applications in many fields. In most cases, small organic molecules are used as templates to synthesize imprinted polymers. In contrast to low molecular weight targets, large biological molecules and cells are more challenging to use as templates to synthesize cell-recognizing materials. This chapter presents an interfacial imprinting method to synthesize bacteria-recognizing polymer beads using Pickering emulsion polymerization. The tendency of bacteria to reside between two immiscible liquids is utilized to create surface-imprinted binding sites on cross-linked polymer microspheres.

13.
Nat Commun ; 12(1): 5076, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34417461

RESUMO

Graphene-based photodetectors have attracted significant attention for high-speed optical communication due to their large bandwidth, compact footprint, and compatibility with silicon-based photonics platform. Large-bandwidth silicon-based optical coherent receivers are crucial elements for large-capacity optical communication networks with advanced modulation formats. Here, we propose and experimentally demonstrate an integrated optical coherent receiver based on a 90-degree optical hybrid and graphene-on-plasmonic slot waveguide photodetectors, featuring a compact footprint and a large bandwidth far exceeding 67 GHz. Combined with the balanced detection, 90 Gbit/s binary phase-shift keying signal is received with a promoted signal-to-noise ratio. Moreover, receptions of 200 Gbit/s quadrature phase-shift keying and 240 Gbit/s 16 quadrature amplitude modulation signals on a single-polarization carrier are realized with a low additional power consumption below 14 fJ/bit. This graphene-based optical coherent receiver will promise potential applications in 400-Gigabit Ethernet and 800-Gigabit Ethernet technology, paving another route for future high-speed coherent optical communication networks.

14.
IEEE Trans Biomed Eng ; PP2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34351853

RESUMO

OBJECTIVE: Catheters and wires are used extensively in cardiac catheterization procedures. Detecting their positions in fluoroscopic X-ray images is important for several clinical applications such as motion compensation and co-registration between 2D and 3D imaging modalities. Detecting the complete length of a catheter or wire object as well as electrode positions on the catheter or wire is a challenging task. METHOD: In this paper, an automatic detection framework for catheters and wires is developed. It is based on path reconstruction from image tensors, which are eigen direction vectors generated from a multiscale vessel enhancement filter. A catheter or a wire object is detected as the smooth path along those eigen direction vectors. Furthermore, a real-time tracking method based on a template generated from the detection method was developed. RESULTS: The proposed framework was tested on a total of 7,754 X-ray images. Detection errors for catheters and guidewires are 0.56 0.28 mm and 0.68 0.33 mm, respectively. The proposed framework was also tested and validated in two clinical applications. For motion compensation using catheter tracking, the 2D target registration errors (TRE) of 1.8 mm 0.9 mm was achieved. For co-registration between 2D X-ray images and 3D models from MRI images, a TRE of 2.3 0.9 mm was achieved. CONCLUSION: A novel and fully automatic detection framework and its clinical applications are developed. SIGNIFICANCE: The proposed framework can be applied to improve the accuracy of image-guidance systems for cardiac catheterization procedures.

15.
Neuromodulation ; 2021 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-34390302

RESUMO

OBJECTIVES: To compare the short- and long-term efficacies as well as tolerability of vagus nerve stimulation (VNS) for the patients with drug-resistant epilepsy (DRE) in comparison with status at baseline. MATERIALS AND METHODS: We conducted a specific and systematic search in online data bases for relevant literature published prior to December 2020. The literature retrieved, including randomized clinical trials (RCTs) and observational studies, were then reviewed, and analyzed. A fixed-effect model was used to evaluate the pooled odds ratio (OR) of responder rates and complications associated with RCTs. A random-effect model was used to generate overall responder rates and overall incidences of complication. RESULTS: A total of 61 studies, featuring 5223 patients, were included in our study. The pooled ORs of responder rates, hoarseness/voice change, throat pain, coughing, dyspnea, paresthesia, muscle pain, and headache during the short-term phase were 2.195 (p = 0.001), 5.527 (p = 0.0001), 0.935 (p = 0.883), 1.119 (p = 0.655), 2.901 (p = 0.005), 1.775 (p = 0.061), 3.606 (p = 0.123), and 0.928 (p = 0.806), respectively. The overall responder rates in 3, 6, 12, 24, 36, 48, and 60 months postoperatively were 0.421, 0.455, 0.401, 0.451, 0.482, 0.502, and 0.508, respectively. The overall incidences of complication were 0.274 for hoarseness/voice change, 0.099 for throat pain, 0.133 for coughing, 0.099 for dyspnea, 0.102 for paresthesia, 0.062 for muscle pain, 0.101 for headache, 0.015 for dysphagia, 0.013 for neck pain, 0.040 for infection, 0.030 for lead fracture, 0.019 for vocal cord palsy, and 0.020 for device malfunction, respectively. CONCLUSIONS: The estimating of efficacy and tolerability, using data from the existing literature, indicated VNS therapy is a safe and effective treatment option for patients with DRE.

16.
Dalton Trans ; 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34351336

RESUMO

To overcome the problem of the sluggish kinetics of the oxygen evolution reaction (OER), it is of great significance to develop an efficient and stable non-noble metal-based OER catalyst for electrocatalytic energy conversion and storage. Herein, a complex of a metal-organic framework and hydroxide is synthesized by performing a ligand etching strategy on FeMn co-doped Ni(OH)2 nanosheets in situ grown on nickel foam (FeMn-Ni(OH)2@MOF/NF). Benefiting from the unique sheet-on-sheet hierarchical structure, multi-metal active nodes and two active materials grown in situ, the resulting FeMn-Ni(OH)2@MOF/NF demonstrated brilliant OER activity with an overpotential of 199 mV to achieve a current density of 10 mA cm-2 and long-term stability. This research will provide a new strategy for the design of high-performance OER electrocatalysts.

17.
Ann Hematol ; 100(10): 2435-2441, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34269836

RESUMO

The presence of paroxysmal nocturnal hemoglobinuria (PNH) clones in aplastic anemia (AA) suggests immunopathogenesis, but when and how PNH clones emerge and proliferate are unclear. Hepatitis-associated aplastic anemia (HAAA) is a special variant of AA, contrarily to idiopathic AA, in HAAA the trigger for immune activation is clearer and represented by the hepatitis and thus serves as a good model for studying PNH clones. Ninety HAAA patients were enrolled, including 61 males and 29 females (median age 21 years). Four hundred three of idiopathic AA have been included as controls. The median time from hepatitis to cytopenia was 50 days (range 0-180 days) and from cytopenia to AA diagnosis was 26 days (range 2-370 days). PNH clones were detected in 8 HAAA patients (8.9%) at diagnosis and in 73 patients with idiopathic AA (IAA) (18.1%). PNH cells accounted for 4.2% (1.09-12.33%) of red cells and/or granulocytes and were more likely to be detected in patients with longer disease history and less severe disease. During follow-up, the cumulative incidence of PNH clones in HAAA increased to 18.9% (17/90). Nine HAAA patients newly developed PNH clones, including six immunosuppressive therapy (IST) nonresponders. The clone size was mostly stable during follow-up, and only 2 of 14 patients showed increased clone size without proof of hemolysis. In conclusion, PNH clones were infrequent in newly diagnosed HAAA, but their frequency increased to one that was similar to the IAA frequency during follow-up. These results suggest that the PNH clone selection/expansion process is dynamic and takes time to establish, confirming that retesting for PNH clones during follow-up is crucial.


Assuntos
Anemia Aplástica/etiologia , Hematopoese , Hemoglobinúria Paroxística/complicações , Hepatite/complicações , Adolescente , Adulto , Anemia Aplástica/patologia , Criança , Pré-Escolar , Células Clonais/patologia , Eritrócitos/patologia , Feminino , Granulócitos/patologia , Hemoglobinúria Paroxística/patologia , Hepatite/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
18.
Am J Hematol ; 96(10): 1232-1240, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34265098

RESUMO

The red blood cell (RBC) lifespan is an important physiological indicator of clear significance in clinical research, used for the differential diagnosis of various diseases such as anemia, compensatory phase hemolysis, and polycythemia. The 15 N-glycine labeling technique is the gold standard method for determining RBC lifespans. However, the usefulness of this technique in clinical settings is seriously hindered by the several weeks required to complete the analyses. Levitt's CO breath test is another reliable technique for determining RBC lifespans, with a simpler protocol giving much faster results, making it more useful in clinical applications. We compared the CO breath test and 15 N-glycine labeling technique for measuring the human RBC lifespan. We investigated human RBC lifespans where each subject undertook both the 15 N-glycine labeling technique and the CO breath test. The correlation between the results from these two methods was analyzed. Eight of the ten subjects successfully completed the study. The RBC lifespan values obtained by Levitt's CO breath test were lower than those obtained by the 15 N-glycine labeling technique. The RBC lifespan values determined from the 15 N-glycine labeling technique and the CO breath test were significantly correlated, with a Pearson correlation coefficient of R = 0.98 (p < 0.05), while the R2 of the linear regression equation was 0.96. The CO breath test exhibits as good performance as the 15 N-glycine labelling technique in distinguishing healthy subjects from subjects with hemolysis. The result suggests that the CO breath test is a reliable method for quickly determining human RBC lifespans in clinical applications.


Assuntos
Eritrócitos/citologia , Adulto , Testes Respiratórios , Monóxido de Carbono/análise , Sobrevivência Celular , Feminino , Glicina/análise , Hemólise , Humanos , Masculino , Pessoa de Meia-Idade , Isótopos de Nitrogênio/análise
20.
Exp Anim ; 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34135271

RESUMO

Transverse aortic constriction (TAC) has been widely used to study cardiac hypertrophy, fibrosis, diastolic dysfunction, and heart failure in rodents. Few studies have been reported in preclinical animal models. The similar physiology and anatomy between non-human primates (NHPs) and humans make NHPs valuable models for disease modeling and testing of drugs and devices. In the current study, we aimed to establish a TAC model in NHPs and characterize the structural and functional profiles of the heart after TAC. A non-absorbable suture was placed around the aorta between the brachiocephalic artery and left common carotid artery to create TAC. NHPs were divided into 2 groups according to pressure gradient (PG): the Mild Group (PG=31.01 ± 12.40 mmHg, n=3) and the Moderate Group (PG=53.00 ± 9.37 mmHg, n=4). At 4 weeks after TAC, animals in both TAC groups developed cardiac hypertrophy: enlarged myocytes and increased wall thickness of the left ventricular (LV) anterior wall. Although both TAC groups had normal systolic function that was similar to a Sham Group, the Moderate Group showed diastolic dysfunction that was associated with more severe cardiac fibrosis, as evidenced by a reduced A wave velocity, large E wave velocity/A wave velocity ratio, and short isovolumic relaxation time corrected by heart rate. Furthermore, no LV arrhythmia was observed in either animal group after TAC. A diastolic dysfunction model with cardiac hypertrophy and fibrosis was successfully developed in NHPs.

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