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1.
Int J Pharm ; 661: 124457, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38992736

RESUMO

Osteoporosis, a prevalent systemic bone metabolic disorder, primarily affects postmenopausal women and is characterized by increased bone fragility and a heightened risk of fractures. The efficacy of current osteoporosis treatments is often limited by non-specific drug targeting and undesirable off-target skeletal side effects. To address this challenge, we have developed a novel hydroxyapatite-responsive drug delivery system. This system utilizes a self-assembled p-phosphonatocalix[4]arene tetradodecyl ether (PC4A12C), engineered to specifically target and sustain the release of osteoporosis medication at sites of bone remodeling. Our focus centers on icariin (ICA), a drug known for its potent osteogenic properties and minimal adverse effects. In vitro, ICA-loaded PC4A12C (ICA@PC4A12C) demonstrated enhanced proliferation, differentiation, and mineralization in bone marrow mesenchymal stem cells (BMSCs). In vivo, ICA@PC4A12C exhibited superior efficacy in specifically targeting bone tissue, ensuring a controlled and slow release of icariin directly within the bone environment. In an osteoporosis mouse model, treatment with ICA@PC4A12C showed notable enhancement in osteogenic activity and a significant increase in bone density compared to ICA alone. These results demonstrate the potential of PC4A12C as an effective drug carrier in the development of advanced antiosteoporotic drug delivery systems.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38522713

RESUMO

Statins, widely prescribed for cholesterol management by inhibiting HMG-CoA reductase in the cholesterol biosynthesis pathway, may also influence vertebrate development. In this study, we investigated the developmental effects of two widely used statins, atorvastatin (ATO) and pravastatin (PRA), on zebrafish offspring. For ATO, we administered doses classified as low (1 µM), medium (5 µM), and high (10 µM), while for PRA, the corresponding concentrations were set at low (18 µM), medium (180 µM), and high (270 µM). Our results showed significant reductions in birth and hatching rates, along with decreased body length in offspring at all ATO concentrations and medium to high PRA concentrations. A notable increase in malformation rates, especially in the spine and heart, was observed across all ATO treatments and in medium and high PRA groups. Additionally, we observed reduced heart contraction rates, decreased heart size, lower bone volumes, and diminished expression of mRNA osteogenic markers. Elevated venous sinus-artery bulb (SV-BA) ratios, increased thoracic area, and abnormal cartilage development were also prominent in all ATO-treated groups. Transcriptome analysis revealed alterations in genes predominantly associated with ion channels. These findings provide insights into the potential impacts of specific concentrations of statins on offspring development and highlight potential gene interactions with statins.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases , Animais , Inibidores de Hidroximetilglutaril-CoA Redutases/toxicidade , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Peixe-Zebra/genética , Transcriptoma , Pravastatina/farmacologia , Pravastatina/uso terapêutico , Atorvastatina/toxicidade , Canais Iônicos
3.
J Biopharm Stat ; : 1-13, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38515248

RESUMO

There is growing interest in understanding geographic patterns of medical device-related adverse events (AEs). A spatial scan method combined with the likelihood ratio test (LRT) for spatial-cluster signal detection over the geographical region is universally used. The spatial scan method used a moving window to scan the entire study region and collected some candidate sub-regions from which the spatial-cluster signal(s) will be found. However, it has some challenges, especially in computation. First, the computational cost increased when the number of sub-regions increased. Second, the computational cost may increase if a large spatial-cluster pattern is present and a flexible-shaped window is used. To reduce the computational cost, we propose a Bayesian nonparametric method that combines the ideas of Markov random field (MRF) to leverage geographical information to find potential signal clusters. Then, the LRT is applied for the detection of spatial cluster signals. The proposed method provides an ability to capture both locally spatially contiguous clusters and globally discontiguous clusters, and is manifested to be effective and tractable using hypothetical Left Ventricular Assist Device (LVAD) data as an illustration.

4.
Plants (Basel) ; 13(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38337906

RESUMO

The brown planthopper (BPH), Nilaparvata lugens (Stål), a rice-specific pest, has risen to the top of the list of significant pathogens and insects in recent years. Host plant-mediated resistance is an efficient strategy for BPH control. Nonetheless, BPH resistance in rice cultivars has succumbed to the emergence of distinct virulent BPH populations. Circular RNAs (circRNAs) play a pivotal role in regulating plant-environment interactions; however, the mechanisms underlying their insect-resistant functions remain largely unexplored. In this study, we conducted an extensive genome-wide analysis using high-throughput sequencing to explore the response of rice circRNAs to BPH infestations. We identified a total of 186 circRNAs in IR56 rice across two distinct virulence groups: IR-IR56-BPH (referring to IR rice infested by IR56-BPH) and IR-TN1-BPH, along with a control group (IR-CK) without BPH infestation. Among them, 39 circRNAs were upregulated, and 43 circRNAs were downregulated in the comparison between IR-IR56-BPH and IR-CK. Furthermore, in comparison with IR-CK, 42 circRNAs exhibited upregulation in IR-TN1-BPH, while 42 circRNAs showed downregulation. The Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis revealed that the targets of differentially expressed circRNAs were considerably enriched in a multitude of biological processes closely linked to the response to BPH infestations. Furthermore, we assessed a total of 20 randomly selected circRNAs along with their corresponding expression levels. Moreover, we validated the regulatory impact of circRNAs on miRNAs and mRNAs. These findings have led us to construct a conceptual model that circRNA is associated with the defense regulatory network in rice, which is likely facilitated by the mediation of their parental genes and competing endogenous RNA (ceRNA) networks. This model contributes to the understanding of several extensively studied processes in rice-BPH interactions.

5.
Invest Ophthalmol Vis Sci ; 65(2): 31, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38381411

RESUMO

Purpose: N4-acetylcytidine (ac4C) is a post-transcriptional RNA modification catalyzed by N-acetyltransferase 10 (NAT10), a critical factor known to influence mRNA stability. However, the role of ac4C in visual development remains unexplored. Methods: Analysis of public datasets and immunohistochemical staining were conducted to assess the expression pattern of nat10 in zebrafish. We used CRISPR/Cas9 and RNAi technologies to knockout (KO) and knockdown (KD) nat10, the zebrafish ortholog of human NAT10, and evaluated its effects on early development. To assess the impact of nat10 knockdown on visual function, we performed comprehensive histological evaluations and behavioral analyses. Transcriptome profiling and real-time (RT)-PCR were utilized to detect alterations in gene expression resulting from the nat10 knockdown. Dot-blot and RNA immunoprecipitation (RIP)-PCR analyses were conducted to verify changes in ac4C levels in both total RNA and opsin mRNA specifically. Additionally, we used the actinomycin D assay to examine the stability of opsin mRNA following the nat10 KD. Results: Our study found that the zebrafish NAT10 protein shares similar structural properties with its human counterpart. We observed that the nat10 gene was prominently expressed in the visual system during early zebrafish development. A deficiency of nat10 in zebrafish embryos resulted in increased mortality and developmental abnormalities. Behavioral and histological assessments indicated significant vision impairment in nat10 KD zebrafish. Transcriptomic analysis and RT-PCR identified substantial downregulation of retinal transcripts related to phototransduction, light response, photoreceptors, and visual perception in the nat10 KD group. Dot-blot and RIP-PCR analyses confirmed a pronounced reduction in ac4C levels in both total RNA and specifically in opsin messenger RNA (mRNA). Additionally, by evaluating mRNA decay in zebrafish treated with actinomycin D, we observed a significant decrease in the stability of opsin mRNA in the nat10 KD group. Conclusions: The ac4C-mediated mRNA modification plays an essential role in maintaining visual development and retinal function. The loss of NAT10-mediated ac4C modification results in significant disruptions to these processes, underlining the importance of this RNA modification in ocular development.


Assuntos
Acetiltransferases , Peixe-Zebra , Humanos , Animais , Peixe-Zebra/genética , Dactinomicina , Opsinas , Opsinas de Bastonetes , RNA/genética , RNA Mensageiro/genética
6.
Int J Biol Macromol ; 259(Pt 2): 129185, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38176485

RESUMO

Polyhydroxyalkanoates (PHA) recovery from industrial wastewater has been highlighted as a promising strategy for a circular bioeconomy. However, the high and varying level of nitrogen in wastewater makes enrichment of mixed microbial culture (MMC) low efficiency. In this study, spatial separation of nitrifiers and denitrifiers was adopted by adding biocarriers in MMC and decreasing the sludge retention time (SRT) to accelerate the enrichment of PHA-storing MMC fed by mixed wastewater containing glycerol and propionate. Nitrifiers and denitrifiers were sustained on biocarriers, obtaining a high total inorganic nitrogen removal and allowing a more efficient selective pressure of a high carbon and nitrogen ratio (C/N) under low SRT conditions. The maximum PHA cell content and relative abundance of PHA-storing bacteria were increased to 60.51 % (SRT 6 d) and 49.62 % (SRT 6 d) with the decrease of SRT, respectively. This study demonstrates an efficient way to highly enrich PHA-storing MMC from crude glycerol, which provide a relevant technical support for high-efficiency enrichment of PHA-storing bacteria in low C/N wastewater.


Assuntos
Poli-Hidroxialcanoatos , Águas Residuárias , Reatores Biológicos/microbiologia , Glicerol , Propionatos , Esgotos , Bactérias , Nitrogênio
7.
J Appl Stat ; 50(11-12): 2373-2387, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37529565

RESUMO

In this paper, we propose a Susceptible-Infected-Removal (SIR) model with time fused coefficients. In particular, our proposed model discovers the underlying time homogeneity pattern for the SIR model's transmission rate and removal rate via Bayesian shrinkage priors. MCMC sampling for the proposed method is facilitated by the nimble package in R. Extensive simulation studies are carried out to examine the empirical performance of the proposed methods. We further apply the proposed methodology to analyze different levels of COVID-19 data in the United States.

8.
Acta Cir Bras ; 38: e380223, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37132752

RESUMO

PURPOSE: To explore the role and mechanism of curcumin (Cur) in reducing oxidative stress damage in rats with nephrolithiasis induced by ethylene glycol (EG). METHODS: Thirty male rats were divided into normal control, model, positive (10% potassium citrate), Cur-10 (10 mg/kg curcumin) and Cur-20 (20 mg/kg curcumin) groups. RESULTS: The results of kidney tissue section stained by hematoxylin-eosin and von Kossa showed that curcumin treatment can inhibit the formation of kidney stones. The biochemical test results showed that the urea (Ur), creatinine (Cr), uric acid (UA), inorganic phosphorus and Ca2+ concentrations in urine decreased after being treated with curcumin. There were significant differences between different doses of curcumin (P < 0.05). Compared with the Cur-10 group, Cur-20 had a more significant inhibitory effect on malondialdehyde (MDA) (P < 0.05). In addition, reverse transcription polymerase chain reaction (PCR) detection and immunohistochemical results indicated that the osteopontin (OPN) in the kidney was significantly reduced after curcumin treatment. CONCLUSIONS: Curcumin could reduce the oxidative stress damage caused by EG-induced kidney stones.


Assuntos
Curcumina , Cálculos Renais , Osteopontina , Animais , Masculino , Ratos , Antioxidantes/metabolismo , Curcumina/farmacologia , Rim , Cálculos Renais/tratamento farmacológico , Cálculos Renais/prevenção & controle , Cálculos Renais/metabolismo , Estresse Oxidativo
9.
Pharm Biol ; 61(1): 416-426, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36786302

RESUMO

CONTEXT: Morroniside (MOR) possesses antiosteoporosis (OP) effects, but its molecular target and relevant mechanisms remain unknown. OBJECTIVE: We investigated the effects of MOR on glucocorticoid-induced OP and osteoblastogenesis and its underlying mechanisms. MATERIALS AND METHODS: The effects of MOR (10-100 µM) on the proliferation and differentiation of MC3T3-E1 cells were studied in vitro. The glucocorticoid-induced zebrafish OP model was treated with 10, 20 and 40 µM MOR for five days to evaluate its effects on vertebral bone density and related osteogenic markers. In addition, molecular targets prediction and molecular docking analysis were carried out to explore the binding interactions of MOR with the target proteins. RESULTS: In cultured MC3T3-E1 cells, 20 µM MOR significantly increased cell viability (1.64 ± 0.12 vs. 0.95 ± 0.16; p < 0.01) and cell differentiation (1.57 ± 0.01 vs. 1.00 ± 0.04; p < 0.01) compared to the control group. MOR treatment significantly ameliorated vertebral bone loss in the glucocorticoid-induced OP zebrafish model (0.86 ± 0.02 vs. 0.40 ± 0.03; p < 0.01) and restored the expression of osteoblast-specific markers, including ALP, Runx2 and Col-І. Ligand-based target prediction and molecular docking revealed the binding interaction between MOR and the glucose pockets in sodium-glucose cotransporter 2 (SGLT2). DISCUSSION AND CONCLUSIONS: These findings demonstrated that MOR treatment promoted osteoblastogenesis and ameliorated glucocorticoid-induced OP by targeting SGLT2, which may provide therapeutic potential in managing glucocorticoid-induced OP.


Assuntos
Glucocorticoides , Osteoporose , Animais , Glucocorticoides/toxicidade , Peixe-Zebra , Linhagem Celular , Simulação de Acoplamento Molecular , Transportador 2 de Glucose-Sódio/efeitos adversos , Transportador 2 de Glucose-Sódio/metabolismo , Diferenciação Celular , Osteogênese , Osteoporose/induzido quimicamente , Osteoporose/tratamento farmacológico , Osteoporose/prevenção & controle , Sódio/efeitos adversos , Sódio/metabolismo , Osteoblastos
10.
Bioresour Technol ; 374: 128758, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36801440

RESUMO

Nitrogen (N) removal from high-salinity wastewater is a major challenge. The aerobic-heterotrophic nitrogen removal (AHNR) process has been demonstrated to be feasible for treating hypersaline wastewater. In this study, Halomonas venusta SND-01, a halophilic strain capable of performing AHNR, was isolated from saltern sediment. The strain achieved ammonium, nitrite, and nitrate removal efficiencies of 98%, 81%, and 100%, respectively. The N balance experiment suggests that this isolate removes N mainly via assimilation. Various functional genes related to N metabolism were found in the genome of the strain, establishing a complex AHNR pathway that includes ammonium assimilation, heterotrophic nitrification-aerobic denitrification, and assimilatory nitrate reduction. Four key enzymes in the N removal process were successfully expressed. The strain exhibited high-adaptability under C/N ratios of 5-15, salinities of 2%-10% (m/v), and pH of 6.5-9.5. Therefore, the strain shows high potential for treating saline wastewater with different inorganic N compositions.


Assuntos
Compostos de Amônio , Nitrificação , Desnitrificação , Compostos de Amônio/metabolismo , Nitratos/metabolismo , Águas Residuárias , Nitrogênio/metabolismo , Aerobiose , Nitritos/metabolismo , Processos Heterotróficos
11.
Chinese Medical Journal ; (24): 1188-1197, 2023.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-980904

RESUMO

BACKGROUND@#Pneumonia-like primary pulmonary lymphoma (PPL) was commonly misdiagnosed as infectious pneumonia, leading to delayed treatment. The purpose of this study was to establish a computed tomography (CT)-based radiomics model to differentiate pneumonia-like PPL from infectious pneumonia.@*METHODS@#In this retrospective study, 79 patients with pneumonia-like PPL and 176 patients with infectious pneumonia from 12 medical centers were enrolled. Patients from center 1 to center 7 were assigned to the training or validation cohort, and the remaining patients from other centers were used as the external test cohort. Radiomics features were extracted from CT images. A three-step procedure was applied for radiomics feature selection and radiomics signature building, including the inter- and intra-class correlation coefficients (ICCs), a one-way analysis of variance (ANOVA), and least absolute shrinkage and selection operator (LASSO). Univariate and multivariate analyses were used to identify the significant clinicoradiological variables and construct a clinical factor model. Two radiologists reviewed the CT images for the external test set. Performance of the radiomics model, clinical factor model, and each radiologist were assessed by receiver operating characteristic, and area under the curve (AUC) was compared.@*RESULTS@#A total of 144 patients (44 with pneumonia-like PPL and 100 infectious pneumonia) were in the training cohort, 38 patients (12 with pneumonia-like PPL and 26 infectious pneumonia) were in the validation cohort, and 73 patients (23 with pneumonia-like PPL and 50 infectious pneumonia) were in the external test cohort. Twenty-three radiomics features were selected to build the radiomics model, which yielded AUCs of 0.95 (95% confidence interval [CI]: 0.94-0.99), 0.93 (95% CI: 0.85-0.98), and 0.94 (95% CI: 0.87-0.99) in the training, validation, and external test cohort, respectively. The AUCs for the two readers and clinical factor model were 0.74 (95% CI: 0.63-0.83), 0.72 (95% CI: 0.62-0.82), and 0.73 (95% CI: 0.62-0.84) in the external test cohort, respectively. The radiomics model outperformed both the readers' interpretation and clinical factor model ( P <0.05).@*CONCLUSIONS@#The CT-based radiomics model may provide an effective and non-invasive tool to differentiate pneumonia-like PPL from infectious pneumonia, which might provide assistance for clinicians in tailoring precise therapy.


Assuntos
Humanos , Estudos Retrospectivos , Pneumonia/diagnóstico por imagem , Análise de Variância , Tomografia Computadorizada por Raios X , Linfoma/diagnóstico por imagem
12.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-970562

RESUMO

To clarify the content characteristics of the main active components and mineral elements of Cynomorium songaricum under different habitat conditions, and further explore the relationship between the quality of C. songaricum and habitats, this study took C. songaricum from 25 different habitats in China as the research object, and measured the contents of 8 main active components and 12 mineral elements separately. Diversity analysis, correlation analysis, principal component analysis and cluster analysis were carried out. The results showed that the genetic diversity of total flavonoids, ursolic acid, ether extract, potassium(K), phosphorus(P) and zinc(Zn) in C. songaricum was high. The coefficient of variation of crude polysaccharide, ether extract, gallic acid, protocatechuic aldehyde, catechin, epicatechin, calcium(Ca), sodium(Na), magnesium(Mg), sulfur(S), iron(Fe), manganese(Mn), selenium(Se) and nickel(Ni) were all over 36%, indicating that the quality of C. songaricum was significantly affected by habitats. There were strong synergistic and weak antagonistic effects among the contents of the 8 active components, and complex antagonistic and synergistic effects among the contents of the 12 mineral elements. Principal component analysis revealed that crude polysaccharide, ursolic acid, catechin, epicatechin and total flavonoids could be used as the characteristic components to evaluate the quality of C. songaricum, and Na, copper(Cu), Mn and Ni were the characteristic elements to evaluate the quality of C. songaricum. In cluster ana-lysis, the second group with the main active components as cluster center had better quality in terms of the content of active substances, and the second group with the mineral elements as cluster center had higher utilization potential in the exploitation of mineral elements. This study could provide a basis for resource evaluation and breeding of excellent varieties of C. songaricum in different habitats, and provide a reference for cultivation and identification of C. songaricum.


Assuntos
Cynomorium , Catequina , Melhoramento Vegetal , Selênio , Éteres , Etil-Éteres , Flavonoides , Extratos Vegetais
13.
Acta cir. bras ; 38: e380223, 2023. graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1439114

RESUMO

Purpose: To explore the role and mechanism of curcumin (Cur) in reducing oxidative stress damage in rats with nephrolithiasis induced by ethylene glycol (EG). Methods: Thirty male rats were divided into normal control, model, positive (10% potassium citrate), Cur-10 (10 mg/kg curcumin) and Cur-20 (20 mg/kg curcumin) groups. Results: The results of kidney tissue section stained by hematoxylin-eosin and von Kossa showed that curcumin treatment can inhibit the formation of kidney stones. The biochemical test results showed that the urea (Ur), creatinine (Cr), uric acid (UA), inorganic phosphorus and Ca2+ concentrations in urine decreased after being treated with curcumin. There were significant differences between different doses of curcumin (P < 0.05). Compared with the Cur-10 group, Cur-20 had a more significant inhibitory effect on malondialdehyde (MDA) (P < 0.05). In addition, reverse transcription polymerase chain reaction (PCR) detection and immunohistochemical results indicated that the osteopontin (OPN) in the kidney was significantly reduced after curcumin treatment. Conclusion: Curcumin could reduce the oxidative stress damage caused by EG-induced kidney stones.


Assuntos
Animais , Masculino , Ratos , Estresse Oxidativo/efeitos dos fármacos , Etilenoglicol/análise , Curcumina/administração & dosagem , Osteopontina/análise , Nefrolitíase/veterinária
14.
Cardiovasc Ther ; 2022: 7145699, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35474714

RESUMO

The cardiovascular system adaptation occurs during pregnancy to ensure adequate maternal circulation. Progesterone (P4) is widely used in hormone therapy to support pregnancy, but little is known about its effects on maternal cardiac function. In this study, we investigated the cardiac repolarization and ion channel expression in pregnant subjects and mice models and studied the effects of P4 administrations on these pregnancy-mediated adaptations. P4 administrations shortened the prolongation of QTC intervals and action potential duration (APD) that occurred during pregnancy, which was mainly attributable to the reduction in the voltage-gated potassium (Kv) current under basal conditions. In vitro studies indicated that P4 regulated the Kv2.1 channel in a bidirectional manner. At a low dose (1 µM), P4 induced upregulation of Kv2.1 through P4 receptor, while at a higher dose (5 µM), P4 downregulated Kv2.1 by targeting microRNA-29b (miR-29b). Our data showed that P4 modulated maternal cardiac repolarization by regulating Kv2.1 channel activity during pregnancy. Kv2.1, as well as miR-29b, might be used as potential therapeutic targets for adaptations of the maternal cardiovascular system or evaluation of progesterone medication during pregnancy.


Assuntos
MicroRNAs , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Potenciais de Ação , Animais , Feminino , Humanos , Camundongos , MicroRNAs/genética , Miócitos Cardíacos , Canais de Potássio de Abertura Dependente da Tensão da Membrana/genética , Gravidez , Progesterona/farmacologia
15.
Sci Total Environ ; 790: 148128, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34098277

RESUMO

The temperature effect on bioelectrochemical reduction of CO2 to acetate with a mixed-culture biocathode in the microbial electrosynthesis was explored. The results showed that maximum acetate amount of 525.84 ± 1.55 mg L-1 and fastest acetate formation of 49.21 ± 0.49 mg L-1 d-1 were obtained under mesophilic conditions. Electron recovery efficiency for CO2 reduction to acetate ranged from 14.50 ± 2.20% to 64.86 ± 2.20%, due to propionate, butyrate and H2 generation. Mesophilic conditions were demonstrated to be more favorable for biofilm formation on the cathode, resulting in a stable and dense biofilm. At phylum level, the relative abundance of Bacteroidetes phylum in the biofilm remarkably increased under mesophilic conditions, compared with that at psychrophilic and thermophilic conditions. At genus level, the Clostridium, Treponema, Acidithiobacillus, Acetobacterium and Acetoanaerobium were found to be dominated genera in the biofilm under mesophilic conditions, while genera diversity decreased under psychrophilic and thermophilic conditions.


Assuntos
Acetatos , Dióxido de Carbono , Clostridium , Eletrodos , Temperatura
17.
Sci Rep ; 11(1): 2920, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33536471

RESUMO

The purpose of this study was to investigate the influence of arterial input function (AIF) selection on the quantification of vertebral perfusion using axial dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). In this study, axial DCE-MRI was performed on 2 vertebrae in each of eight healthy volunteers (mean age, 36.9 years; 5 men) using a 1.5-T scanner. The pharmacokinetic parameters Ktrans, ve, and vp, derived using a Tofts model on axial DCE-MRI of the lumbar vertebrae, were evaluated using various AIFs: the population-based aortic AIF (AIF_PA), a patient-specific aortic AIF (AIF_A) and a patient-specific segmental arterial AIF (AIF_SA). Additionally, peaks and delay times were changed to simulate the effects of various AIFs on the calculation of perfusion parameters. Nonparametric analyses including the Wilcoxon signed rank test and the Kruskal-Wallis test with a Dunn-Bonferroni post hoc analysis were performed. In simulation, Ktrans and ve increased as the peak in the AIF decreased, but vp increased when delay time in the AIF increased. In humans, the estimated Ktrans and ve were significantly smaller using AIF_A compared to AIF_SA no matter the computation style (pixel-wise or region-of-interest based). Both these perfusion parameters were significantly greater using AIF_SA compared to AIF_A.


Assuntos
Vértebras Lombares/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Imagem de Perfusão/métodos , Adulto , Feminino , Voluntários Saudáveis , Humanos , Interpretação de Imagem Assistida por Computador , Vértebras Lombares/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Adulto Jovem
18.
J Mol Model ; 27(2): 38, 2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33447954

RESUMO

In this paper, the reaction process of N2 convert to NH3 catalyzed by Ag (111) surface was obtained through the construction of Ag (111) surface and computational simulation. The charge transfer in the reaction process and the change of N≡N bond length are described. Since the N2 reduction reaction (NRR) usually occurs under alkaline solution conditions, we calculated and described the coexistence of OH* and N2. At the same time, the co-adsorption structure of OH* and N2 at different adsorption sites was studied.

19.
Transplant Proc ; 53(2): 665-672, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33341262

RESUMO

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.


Assuntos
Antivirais/uso terapêutico , Transplante de Coração , Hepatite C/tratamento farmacológico , Adulto , Idoso , Medicamentos Genéricos/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resposta Viral Sustentada
20.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-902407

RESUMO

Objective@#To evaluate the feasibility of texture analysis on non-contrast-enhanced T1 maps of cardiac magnetic resonance (CMR) imaging for the diagnosis of myocardial injury in acute myocardial infarction (MI). @*Materials and Methods@#This study included 68 patients (57 males and 11 females; mean age, 55.7 ± 10.5 years) with acute ST-segment-elevation MI who had undergone 3T CMR after a percutaneous coronary intervention. Forty patients of them also underwent a 6-month follow-up CMR. The CMR protocol included T2-weighted imaging, T1 mapping, rest first-pass perfusion, and late gadolinium enhancement. Radiomics features were extracted from the T1 maps using open-source software. Radiomics signatures were constructed with the selected strongest features to evaluate the myocardial injury severity and predict the recovery of left ventricular (LV) longitudinal systolic myocardial contractility. @*Results@#A total of 1088 segments of the acute CMR images were analyzed; 103 (9.5%) segments showed microvascular obstruction (MVO), and 557 (51.2%) segments showed MI. A total of 640 segments were included in the 6-month follow-up analysis, of which 160 (25.0%) segments showed favorable recovery of LV longitudinal systolic myocardial contractility.Combined radiomics signature and T1 values resulted in a higher diagnostic performance for MVO compared to T1 values alone (area under the curve [AUC] in the training set; 0.88, 0.72, p = 0.031: AUC in the test set; 0.86, 0.71, p = 0.002).Combined radiomics signature and T1 values also provided a higher predictive value for LV longitudinal systolic myocardial contractility recovery compared to T1 values (AUC in the training set; 0.76, 0.55, p < 0.001: AUC in the test set; 0.77, 0.60, p < 0.001). @*Conclusion@#The combination of radiomics of non-contrast-enhanced T1 mapping and T1 values could provide higher diagnostic accuracy for MVO. Radiomics also provides incremental value in the prediction of LV longitudinal systolic myocardial contractility at six months.

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