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2.
PeerJ ; 12: e17275, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650646

RESUMO

Background: Sect. Chrysantha Chang, belonging to the Camellia genus, is one of the rare and precious ornamental plants distinguished by a distinctive array of yellow-toned petals. However, the variation mechanisms of petal color in Sect. Chrysantha Chang remains largely unclear. Methods: We conducted an integrated analysis of metabolome and transcriptome to reveal petal coloration mechanism in three species, which have different yellow tones petals, including C. chuongtsoensis (CZ, golden yellow), C. achrysantha (ZD, light yellow), and C. parvipetala (XB, milk white). Results: A total of 356 flavonoid metabolites were detected, and 295 differential metabolites were screened. The contents of 74 differential metabolites showed an upward trend and 19 metabolites showed a downward trend, among which 11 metabolites were annotated to the KEGG pathway database. We speculated that 10 metabolites were closely related to the deepening of the yellowness. Transcriptome analysis indicated that there were 2,948, 14,018 and 13,366 differentially expressed genes (DEGs) between CZ vs. ZD, CZ vs. XB and ZD vs. XB, respectively. Six key structural genes (CcCHI, CcFLS, CcDFR1, CcDFR2, CcDFR3, and CcCYP75B1) and five candidate transcription factors (MYB22, MYB28, MYB17, EREBP9, and EREBP13) were involved in the regulation of flavonoid metabolites. The findings indicate that flavonoid compounds influence the color intensity of yellow-toned petals in Sect. Chrysantha Chang. Our results provide a new perspective on the molecular mechanisms underlying flower color variation and present potential candidate genes for Camellia breeding.


Assuntos
Camellia , Flores , Regulação da Expressão Gênica de Plantas , Metaboloma , Pigmentação , Transcriptoma , Flores/genética , Flores/metabolismo , Metaboloma/genética , Pigmentação/genética , Camellia/genética , Camellia/metabolismo , Flavonoides/metabolismo , Perfilação da Expressão Gênica
3.
Sci Rep ; 14(1): 2988, 2024 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-38316805

RESUMO

Ginger has been associated with a decreased incidence of colorectal cancer (CRC) through reduction in inflammatory pathways and inhibition of tumor growth. Recent pre-clinical models have implicated changes in the gut microbiome as a possible mediator of the ginger effect on CRC. We hypothesized that, in adults previously diagnosed with a colorectal adenoma, ginger supplementation would alter the fecal microbiome in the direction consistent with its CRC-inhibitory effect. Sixty-eight adults were randomized to take either ginger or placebo daily for 6 weeks, with a 6-week washout and longitudinal stool collection throughout. We performed 16S rRNA sequencing and evaluated changes in overall microbial diversity and the relative abundances of pre-specified CRC-associated taxa using mixed-effects logistic regression. Ginger supplementation showed no significant effect on microbial community structure through alpha or beta diversity. Of 10 pre-specified CRC-associated taxa, there were significant decreases in the relative abundances of the genera Akkermansia (p < 0.001), Bacteroides (p = 0.018), and Ruminococcus (p = 0.013) after 6-week treatment with ginger compared to placebo. Ginger supplementation led to decreased abundances of Akkermansia and Bacteroides, which suggests that ginger may have an inhibitory effect on CRC-associated taxa. Overall, ginger supplementation appears to have a limited effect on gut microbiome in patients with colorectal adenomas.


Assuntos
Adenoma , Neoplasias Colorretais , Microbiota , Zingiber officinale , Adulto , Humanos , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/análise , Neoplasias Colorretais/patologia , Fezes/química , Adenoma/tratamento farmacológico , Suplementos Nutricionais
4.
Front Plant Sci ; 15: 1330075, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38322825

RESUMO

Maire yew (Taxus mairei), an evergreen conifer, has high ornamental and medicinal value. The arils of this species has three different colors. However, the variation mechanisms of arils color formation remains unclear. Here, the gene expression and metabolite concentration were profiled for red (RTM), yellow (YTM), and purple (PTM) arils in different developmental stages. A total of 266 flavonoids and 35 carotenoids were identified. The predominant pigments identified in YTM were epiafzelechin, lutein, and ß-Cryptoxanthin, while malvidin-3,5-di-O-glucoside and apigenin played crucial roles in PTM. And significant differential expression was observed among the HCT, DFR, LAR, ANS, crtB, NCED, and CCoAOMT genes across different color arils. During the maturation of yellow arils, the upregulation of HCT was strongly correlated with the accumulation of epiafzelechin. The diminished expression of DFR, LAR, and ANS seemed to inhibit the production of delphinidin-3-O-rutinoside. The decrease in crtB expression and concurrent increase in NCED expression potentially regulate the heightened accumulation of lutein. Meanwhile, the accumulation of ß-cryptoxanthin appeared seemed to be positively influenced by NCED. As aril turning purple, the decreased expression of CCoAOMT seemed to facilitate the synthesis of apigenin. The substantial upregulation of DFR promoted the production of malvidin-3,5-di-O-glucoside. Additionally, the overexpression of MYBs may plays the important role in regulating the formation of different colored arils. In total, 14 genes were selected for qRT-PCR validation, the results indicated the reliability of the transcriptome sequences data. Our findings could provide valuable insight into the molecular breeding, development, and application of Maire yew resources.

5.
BMC Plant Biol ; 23(1): 567, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37968605

RESUMO

BACKGROUND: Edgeworthia chrysantha, a deciduous shrub endemic to China, is known for its high ornamental value, extensive cultivation history, and wide-ranging applications. However, theoretical research on this plant is severely lacking. While its flowering process displays striking color transitions from green (S1) to yellow (S2) and then to white (S3), the scientific exploration of this phenomenon is limited, and the underlying regulatory mechanisms are yet to be elucidated. RESULTS: Correlation analysis between phenotypic measurements and pigment content revealed that carotenoids and chlorophyll are the key pigments responsible for the color changes. Metabolomic analysis of carotenoids demonstrated that lutein and ß-carotene were present at higher levels in S1, while S2 exhibited increased diversity and quantity of carotenoids compared to other stages. Notably, antheraxanthin, zeaxanthin, lycopene, and α-cryptoxanthin showed significant increases. In S3, apart from the colorless phytoene, other carotenoid metabolites were significantly reduced to extremely low levels. Transcriptomic data indicated that PSY, Z-ISO, crtZ, ZEP, PDS and ZDS are key genes involved in carotenoid biosynthesis and accumulation, while NCED plays a crucial role in carotenoid degradation. SGR was identified as a key gene contributing to the progressive decline in chlorophyll content. Additionally, three transcription factors potentially regulating carotenoid metabolism were also identified. CONCLUSIONS: This study represents the first systematic investigation, spanning from phenotypic to molecular levels, of the color-changing phenomenon in E. chrysantha. The study elucidates the crucial pigments, metabolites, genes, and transcription factors responsible for flower color changes during the flowering process, thereby providing preliminary understanding of the intrinsic regulatory mechanisms. These findings establish a theoretical foundation for the genetic improvement of flower color in E. chrysantha.


Assuntos
Thymelaeaceae , Transcriptoma , Carotenoides/metabolismo , Clorofila/metabolismo , Fatores de Transcrição/genética , Metaboloma , Thymelaeaceae/metabolismo , Regulação da Expressão Gênica de Plantas
6.
Ecol Evol ; 13(8): e10374, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37636866

RESUMO

Phellodendron has always been of great significance in promoting human health and ecological restoration. However, human activities and climate change have severely affected habitat, population dynamics and sustainable use of Phellodendron. Little is known about the geographical distribution pattern and their responses to climate change of Phellodendron. In order to reveal the impact of climate change on Phellodendron, we conducted a study based on natural distribution data of two species (297 occurrence points), 20 environmental factors, and an optimized MaxEnt model. Our results identified the main environmental factors influencing Phellodendron, predicted their potential geographical distribution, and assessed migration trends under climate change in China. Our analysis showed that Ph. amurense and Ph. chinense have potential suitable habitats of 62.89 × 104 and 70.71 × 104 km2, respectively. Temperature and precipitation were found to play an essential role in shaping the present geographical distribution of Phellodendron populations. Based on two future climate scenarios, we forecasted that the potential suitable habitat of Ph. amurense would decrease by 12.52% (SSP245) and increase by 25.28% (SSP585), while Ph. chinense would decline by 19.61% (SSP245) and 15.78% (SSP585) in the late-21st century. The potential suitable habitats of Ph. amurense and Ph. chinense would shift to northward and westward, respectively. Hydrothermal change was found to be the primary driver of the suitable habitat of Phellodendron populations in the future. We recommend establishing nature reserves for existing Phellodendron populations, especially Ph. chinense. Our study provided a practical framework for the impact of climate change on the suitable habitat of Phellodendron species and guided regional cultivation, long-term conservation, and sustainable use.

7.
J Clin Pharmacol ; 63(12): 1417-1429, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37507728

RESUMO

Pharmacokinetic (PK) comparisons between therapeutic biologics have largely been based on the total area under the concentration-time curve (AUC) and the maximum concentration (Cmax ). For biologics with a long half-life, a PK comparability study may be long in duration and costly to conduct. The goal of this study was to evaluate whether a truncated AUC (tAUC) can be used to assess PK comparability when bridging prefilled syringe (PFS) and autoinjector (AI) treatment options for biologics with a long half-life. Fifteen biologics license applications (BLAs) were included to determine the concordance and geometric percent coefficient of variation (%CV) between tAUCs evaluated on days 7, 14, 21, and 28 and AUC evaluated to infinity (AUC0-inf ). Concordance is established if the tAUCs are comparable with AUC0-inf . Trial simulation was performed to examine the effect of the absorption rate constant (ka ) and sample size on the concordance of tAUCs. The tAUCs evaluated on day 14, 21, and 28 had 100% concordance with AUC0-inf for all 15 BLAs. The concordance of tAUC evaluated at day 7 was 87.5%. Based on the trial simulation, tAUC evaluated to day 28 post-dose can achieve high concordance (≥85%) for biologics exhibiting linear or nonlinear elimination with a ka of ≥0.1/day and with a sample size of 70 subjects per arm. tAUC appears to be a promising alternative PK measure, relative to AUC0-inf , for PK comparability assessments.


Assuntos
Medicamentos Biossimilares , Seringas , Humanos , Equivalência Terapêutica , Área Sob a Curva , Medicamentos Biossimilares/farmacocinética , Injeções Subcutâneas
8.
Br J Clin Pharmacol ; 89(10): 2964-2976, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37202871

RESUMO

AIMS: The aim of this study was to quantify identifiable sources of variability, including key pharmacogenetic variants in oxypurinol pharmacokinetics and their pharmacodynamic effect on serum urate (SU). METHODS: Hmong participants (n = 34) received 100 mg allopurinol twice daily for 7 days followed by 150 mg allopurinol twice daily for 7 days. A sequential population pharmacokinetic pharmacodynamics (PKPD) analysis with non-linear mixed effects modelling was performed. Allopurinol maintenance dose to achieve target SU was simulated based on the final PKPD model. RESULTS: A one-compartment model with first-order absorption and elimination best described the oxypurinol concentration-time data. Inhibition of SU by oxypurinol was described with a direct inhibitory Emax model using steady-state oxypurinol concentrations. Fat-free body mass, estimated creatinine clearance and SLC22A12 rs505802 genotype (0.32 per T allele, 95% CI 0.13, 0.55) were found to predict differences in oxypurinol clearance. Oxypurinol concentration required to inhibit 50% of xanthine dehydrogenase activity was affected by PDZK1 rs12129861 genotype (-0.27 per A allele, 95% CI -0.38, -0.13). Most individuals with both PDZK1 rs12129861 AA and SLC22A12 rs505802 CC genotypes achieve target SU (with at least 75% success rate) with allopurinol below the maximum dose, regardless of renal function and body mass. In contrast, individuals with both PDZK1 rs12129861 GG and SLC22A12 rs505802 TT genotypes would require more than the maximum dose, thus requiring selection of alternative medications. CONCLUSIONS: The proposed allopurinol dosing guide uses individuals' fat-free mass, renal function and SLC22A12 rs505802 and PDZK1 rs12129861 genotypes to achieve target SU.


Assuntos
Gota , Hiperuricemia , Transportadores de Ânions Orgânicos , Adulto , Humanos , Oxipurinol , Alopurinol/farmacocinética , Hiperuricemia/tratamento farmacológico , Hiperuricemia/genética , Supressores da Gota/farmacocinética , Farmacogenética , Gota/tratamento farmacológico , Gota/genética , Transportadores de Ânions Orgânicos/uso terapêutico , Proteínas de Transporte de Cátions Orgânicos/genética
9.
PLoS One ; 18(2): e0279830, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36724193

RESUMO

BACKGROUND: Hmong men in Minnesota exhibit a high prevalence of gout and hyperuricemia. Although evidence of vitamin C's effectiveness as a treatment for gout is mixed, analysis of therapeutic benefit based on an individual's multiomic signature may identify predictive markers of treatment success. OBJECTIVES: The primary objective of the Hmong Microbiome ANd Gout, Obesity, Vitamin C (HMANGO-C) study was to assess the effectiveness of vitamin C on serum urate in Hmong adults with and without gout/hyperuricemia. The secondary objectives were to assess if 1) vitamin C impacts the taxonomic and functional patterns of microbiota; 2) taxonomic and functional patterns of microbiota impact vitamin C's urate-lowering effects; 3) genetic variations impact vitamin C's urate-lowering effects; 4) differential microbial biomarkers exist for patients with or without gout; and 5) there is an association between obesity, gut microbiota and gout/hyperuricemia. METHODS: This prospective open-labelled clinical trial was guided by community-based participatory research principles and conducted under research safety restrictions for SARS-CoV-2. We aimed to enroll a convenient sample of 180 Hmong adults (120 with gout/hyperuricemia and 60 without gout/hyperuricemia) who provided medical, demographic, dietary and anthropometric information. Participants took vitamin C 500mg twice daily for 8 weeks and provided pre-and post- samples of blood and urine for urate measurements as well as stool samples for gut microbiome. Salivary DNA was also collected for genetic markers relevant to uric acid disposition. EXPECTED RESULTS: We expected to quantify the impact of vitamin C on serum urate in Hmong adults with and without gout/hyperuricemia. The outcome will enhance our understanding of how gut microbiome and genomic variants impact the urate-lowering of vitamin C and associations between obesity, gut microbiota and gout/hyperuricemia. Ultimately, findings may improve our understanding of the causes and potential interventions that could be used to address health disparities in the prevalence and management of gout in this underserved population. TRIAL REGISTRATION: ClinicalTrials.gov NCT04938024 (first posted: 06/24/2021).


Assuntos
COVID-19 , Gota , Hiperuricemia , Microbiota , Masculino , Adulto , Humanos , Ácido Úrico , Ácido Ascórbico/uso terapêutico , Estudos Prospectivos , COVID-19/complicações , SARS-CoV-2 , Gota/tratamento farmacológico , Gota/epidemiologia , Gota/genética , Supressores da Gota/uso terapêutico , Obesidade/epidemiologia , Obesidade/genética , Obesidade/complicações , Vitaminas/uso terapêutico , Microbiota/genética , Ensaios Clínicos Fase II como Assunto
10.
J Hazard Mater ; 447: 130762, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36638676

RESUMO

Microplastic threats to biodiversity, health and ecological safety are adding to concern worldwide, but the real impacts on the functioning of organisms and ecosystems are obscure owing to their inert characteristics. Here we investigated the long-lasting ecological effects of six prevalent microplastic types: polyethylene (PE), polypropylene (PP), polyamide (PA), polystyrene (PS), polyethylene terephthalate (PET), and polyvinyl chloride (PVC) on soil bacteria at a 2 % (w/w) level. Due to the inertia and lack of available nitrogen of these microplastics, their effects on bacteriome tended to converge after one year and were strongly different from their short-term effects. The soil volumes around microplastics were very specific, in which the microplastic-adapted bacteria (e.g., some genera in Actinobacteria) were enriched but the phyla Bacteroidetes and Gemmatimonadetes declined, resulting in higher microbial nitrogen requirements and reduced organic carbon mineralization. The reshaped bacteriome was specialized in the genetic potential of xenobiotic and lipid metabolism as well as related oxidation, esterification, and hydrolysis processes, but excessive oxidative damage resulted in severe weakness in community genetic information processing. According to model predictions, microplastic effects are indirectly derived from nutrients and oxidative stress, and the effects on bacterial functions are stronger than on structure, posing a heavy risk to soil ecosystems.


Assuntos
Microplásticos , Plásticos , Microplásticos/toxicidade , Plásticos/toxicidade , Ecossistema , Solo , Polipropilenos , Bactérias/genética
11.
Cureus ; 14(9): e28905, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36249660

RESUMO

Background Previous research predicted that Hmong, an understudied East Asian subpopulation, might require significantly lower warfarin doses than East Asian patients partially due to their unique genetic and clinical factors. However, such findings have not been corroborated using real-world data. Methods This was a retrospective cohort study of Hmong and East Asian patients receiving warfarin. Warfarin stable doses (WSD) and time to the composite outcome, including international normalized ratio (INR) greater than four incidences or major bleeding within six months of warfarin initiation, were compared. Results This cohort study included 55 Hmong and 100 East Asian patients. Compared to East Asian patients, Hmong had a lower mean WSD (14.5 vs. 20.4 mg/week, p<0.05). In addition, Hmong had a 3.1-fold (95% CI: 1.1-9.3, p<0.05) higher hazard of the composite outcome. Conclusion Using real-world data, significant differences in warfarin dosing and hazard for the composite outcome of INR>4 and major bleeding were observed between Hmong and East Asian patients. These observations further underscore the importance of recognizing subpopulation-based differences in warfarin dosing and outcomes.

12.
Pharmacogenomics ; 23(16): 873-885, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36314296

RESUMO

Aims: To assess knowledge and attitudes toward pharmacogenomics (PGx) of incoming doctoral pharmacy students, to evaluate the internal structure and reliability of the PGx survey and to identify variables associated with the different responses. Methods: A PGx survey based on the core pharmacist competencies in PGx was created. Results: Of 83.2% analyzable responses, 91% believed PGx is a useful tool and relevant to future practice but over 70% stated they lack confidence in clinical PGx knowledge. This 38-item PGx survey included three factors showing high reliability. Prior genetic/PGx testing and unsatisfactory medication experiences were associated with a more positive attitude toward PGx. Conclusion: The majority of students have positive attitudes toward PGx, but lack knowledge in genetic concepts and clinical PGx.


A pharmacogenomics (PGx) survey with high reliability showed that incoming doctoral pharmacy students have positive attitudes toward PGx, but lack knowledge of genetic concepts and clinical PGx.


Assuntos
Estudantes de Farmácia , Humanos , Farmacogenética/educação , Reprodutibilidade dos Testes , Farmacêuticos , Atitude
13.
Ecol Evol ; 12(9): e9302, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36177121

RESUMO

Climate change affects the species spatio-temporal distribution deeply. However, how climate affects the spatio-temporal distribution pattern of related species on the large scale remains largely unclear. Here, we selected two closely related species in Taxus genus Taxus chinensis and Taxus mairei to explore their distribution pattern. Four environmental variables were employed to simulate the distribution patterns using the optimized Maxent model. The results showed that the highly suitable area of T. chinensis and T. mairei in current period was 1.616 × 105 km2 and 3.093 × 105 km2, respectively. The distribution area of T. chinensis was smaller than that of T. mairei in different periods. Comparison of different periods shown that the distribution area of the two species was almost in stasis from LIG to the future periods. Temperature and precipitation were the main climate factors that determined the potential distribution of the two species. The centroids of T. chinensis and T. mairei were in Sichuan and Hunan provinces in current period, respectively. In the future, the centroid migration direction of the two species would shift towards northeast. Our results revealed that the average elevation distribution of T. chinensis was higher than that of T. mairei. This study sheds new insights into the habitat preference and limiting environment factors of the two related species and provides a valuable reference for the conservation of these two threatened species.

14.
Front Genet ; 13: 995748, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36134031

RESUMO

Hibiscus syriacus L. var. Shigyoku is a new double-flowered bluish-purple variety in China that changes color during flower development from bluish-purple to light purple. There is limited information on the anthocyanin accumulation patterns and associated transcriptome signatures in Shigyoku from D1 (bud) to open flower (D3). Here, we employed a combined transcriptome and metabolome approach to understanding the mechanism of this color change. Our results demonstrate that cyanidins, pelargonidins, delphinidins, petunidins, peonidins, and malvidins were differentially accumulated in Shigyoku petals. The anthocyanin biosynthesis started in D1, was significantly upregulated in D2 (semi-open flower), and reduced in D3. However, malvidins, pelargonidins, and peonidins could be associated with the bluish-purple coloration on D2. Their reduced accumulation in D3 imparted the light purple coloration to Shigyoku petals on D3. Significant contributions in the color change could be associated with the expression changes in anthocyanin biosynthesis genes i.e., LARs, ANSs, DFRs, UGT79B1, C3'Hs, 3ATs, and BZ1s. The UFGTs were associated with the higher accumulation of glycosylated anthocyanins in D2 and D3. Furthermore, the changes in the expressions of the MYB and bHLH transcription factors were consistent with the anthocyanin accumulation. Finally, we discussed the possible roles of Jasmonic acid, auxin, and gibberellic acid signaling in regulating the MBW complex. Taken together, we conclude that H. syriacus petal coloration is associated with anthocyanin biosynthesis genes, the MBW complex, and phytohormone signaling.

15.
Front Genet ; 13: 1070236, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36685861

RESUMO

Underrepresentation of subpopulations within geo-ancestral groups engaged in research can exacerbate health disparities and impair progress toward personalized medicine. This is particularly important when implementing pharmacogenomics which uses genomic-based sources of variability to guide medication selection and dosing. This mini-review focuses on pharmacogenomic findings with Hmong in the United States and their potential clinical implications. By actively engaging Hmong community in pharmacogenomic-based research, several clinically relevant differences in allele frequencies were observed within key pharmacogenes such as CYP2C9 and CYP2C19 in Hmong compared to those in either East Asians or Europeans. Additionally, using state-of-the-art genome sequencing approaches, Hmong appear to possess novel genetic variants within CYP2D6, a critical pharmacogene affecting pharmacokinetics of a broad range of medications. The allele frequency differences and novel alleles in Hmong have translational impact and real-world clinical consequences. For example, Hmong patients exhibited a lower warfarin stable dose requirement compared to East Asian patients. This was predicted based on Hmong's unique genetic and non-genetic factors and confirmed using real-world data from clinical practice settings. By presenting evidence of the genetic uniqueness and its translational impact within subpopulations, such as the Hmong, we hope to inspire greater inclusion of other geo-ancestrally underrepresented subpopulations in pharmacogenomic-based research.

16.
Bioact Mater ; 6(12): 4654-4669, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34095623

RESUMO

Magnesium (Mg) and its alloys have attracted attention as potential biodegradable materials in orthopedics due to their mechanical and physical properties, which are compatible with those of human bone. However, the effect of the mismatch between the rapid material degradation and fracture healing caused by the adverse effect of hydrogen (H2), which is generated during degradation, on surrounding bone tissue has severely restricted the application of Mg and its alloys. Thus, the development of new Mg alloys to achieve ideal degradation rates, H2 evolution and mechanical properties is necessary. Herein, a novel Mg-1Zn-1Sn-xSr (x = 0, 0.2, 0.4, and 0.6 wt%) quaternary alloy was developed, and the microstructure, mechanical properties, corrosion behavior and biocompatibility in vitro/vivo were investigated. The results demonstrated that a minor amount of strontium (Sr) (0.2 wt %) enhanced the corrosion resistance and mechanical properties of Mg-1Zn-1Sn alloy through grain refinement and second phase strengthening. Simultaneously, due to the high hydrogen overpotential of tin (Sn), the H2 release of the alloys was significantly reduced. Furthermore, Sr-containing Mg-1Zn-1Sn-based alloys significantly enhanced the viability, adhesion and spreading of MC3T3-E1 cells in vitro due to their unique biological activity and the ability to spontaneously form a network structure layer with micro/nanotopography. A low corrosion rate and improved biocompatibility were also maintained in a rat subcutaneous implantation model. However, excessive Sr (>0.2 wt %) led to a microgalvanic reaction and accelerated corrosion and H2 evolution. Considering the corrosion resistance, H2 evolution, mechanical properties and biocompatibility in vitro and in vivo, Mg-1Zn-1Sn-0.2Sr alloy has tremendous potential for clinical applications.

17.
Materials (Basel) ; 14(7)2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33806127

RESUMO

Mg-Zn-Sn-based alloys are widely used in the industrial field because of their low-cost, high-strength and heat-resistant characteristics. However, their application in the biomedical field has been rarely reported. In the present study, biodegradable Mg-1Zn-1Sn and Mg-1Zn-1Sn-0.2Sr alloys were fabricated. Their microstructure, surface characteristics, mechanical properties and bio-corrosion properties were carried out using an optical microscope (OM), X-ray diffraction (XRD), electron microscopy (SEM), mechanical testing, electrochemical and immersion test. The cell viability and morphology were studied by cell counting kit-8 (CCK-8) assay, live/dead cell assay, confocal laser scanning microscopy (CLSM) and SEM. The osteogenic activity was systematically investigated by alkaline phosphatase (ALP) assay, Alizarin Red S (ARS) staining, immunofluorescence staining and quantitative real time-polymerase chain reaction (qRT-PCR). The results showed that a small amount of strontium (Sr) (0.2 wt.%) significantly enhanced the corrosion resistance of the Mg-1Zn-1Sn alloy by grain refinement and decreasing the corrosion current density. Meanwhile, the mechanical properties were also improved via the second phase strengthening. Both Mg-1Zn-1Sn and Mg-1Zn-1Sn-0.2Sr alloys showed excellent biocompatibility, significantly promoted cell proliferation, adhesion and spreading. Particularly, significant increases in ALP activity, ARS staining, type I collagen (COL-I) expression as well as the expressions of three osteogenesis-related genes (runt-related transcription factor 2 (Runx2), osteopontin (OPN), and osteocalcin (Bglap)) were observed for the Mg-1Zn-1Sn-0.2Sr group. In summary, this study demonstrated that Mg-Zn-Sn-based alloy has great application potential in orthopedics and Sr is an ideal alloying element of Mg-Zn-Sn-based alloy, which optimizes its corrosion resistance, mechanical properties and osteoinductive activity.

18.
J Biomater Appl ; 36(3): 474-480, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33596708

RESUMO

Clinical treatment of bone defects caused by trauma, tumor resection and other bone diseases, especially bone defects that can lead to infection, remains a major challenge. Currently, autologous bone implantation is the gold standard for treatment of bone defects, but it is limited by secondary trauma and insufficient autologous material. Moreover, postoperative infection is an important factor affecting bone healing.AcN-RADARADARADARADA-CONH2 (RADA) is a new type of self-assembling peptide(SAP) composed of Arg,Ala,Asp and other amino acids was designed and prepared. The "RADA" self-assembling peptide hydrogels has excellent biological activity and it's completely biodegradable and non-toxic.It is also have been confirmed to promote cell proliferation, wound healing, tissue repair, and drug delivery. To promote bone regeneration and simultaneously prevent bacterial infection, we designed biocomposite scaffolds comprising RADA and calcium phosphate cement (CPC), termed RADA-CPC. The morphological features of the scaffold were characterized by scanning electron microscopy (SEM). In vitro studies demonstrated that RADA-CPC enhances osteoblast proliferation, differentiation and mineralization. In addition, the scaffold was used as a drug delivery system to treat postoperative infections by sustained release of ciprofloxacin (CIP). The RADA-CPC scaffold may have potential application prospects in orthopedics field because of its role in promoting bone repair and as a sustained-release drug carrier to prevent infections.


Assuntos
Antibacterianos/administração & dosagem , Materiais Biocompatíveis/química , Fosfatos de Cálcio/química , Ciprofloxacina/administração & dosagem , Preparações de Ação Retardada/química , Peptídeos/química , Células 3T3 , Animais , Materiais Biocompatíveis/farmacologia , Regeneração Óssea/efeitos dos fármacos , Fosfatos de Cálcio/farmacologia , Proliferação de Células/efeitos dos fármacos , Preparações de Ação Retardada/farmacologia , Camundongos , Peptídeos/farmacologia , Alicerces Teciduais/química
19.
Pharmacotherapy ; 41(3): 265-276, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33202062

RESUMO

INTRODUCTION: Warfarin's narrow therapeutic index and high variability in dosage requirements make dosage selection critical. Genetic factors are known to impact warfarin dosage selection. The Hmong are a unique Asian subpopulation numbering over 278,000 in the United States whose participation in genetics-based research is virtually nonexistent. The translational significance of early reports of warfarin pharmacogene differences in Hmong has not been evaluated. OBJECTIVES: (i) To validate previously identified allele frequency differences relevant to warfarin dosing in Hmong versus East Asians and (ii) to compare predicted warfarin sensitivity and maintenance doses between a Hmong population and an East Asian cohort. METHOD: DNA collected from two independent cohorts (n=236 and n=198) of Hmong adults were genotyped for CYP2C9 (*2, *3), VKORC1 (G-1639A), and CYP4F2 (*3). Allele frequencies between the combined Hmong cohort (n=433) and East Asians (n=1165) from the 2009 International Warfarin Pharmacogenetics Consortium (IWPC) study were compared using a χ2 test. Percentages of Hmong and East Asian participants predicted to be very sensitive to warfarin were compared using a χ2 test, and the predicted mean warfarin maintenance dose was compared with a t test. RESULTS: The allele frequencies of CYP2C9*3 in the combined Hmong cohort and CYP4F2*3 in the VIP-Hmong cohort are significantly different from those in East Asians (18.9% vs 3.0%, p<0.001 and 9.8% vs 22.1%, p<0.001, respectively). Comparing the combined Hmong cohort to the East Asian cohort, the percentage of participants predicted to be very sensitive to warfarin was significantly higher (28% vs 5%, p<0.01) and the mean predicted warfarin maintenance dose was significantly lower (19.8 vs 21.3 mg/week, p<0.001), respectively. CONCLUSION: The unique allele frequencies related to warfarin when combined with nongenetic factors observed in the Hmong translate into clinically relevant differences in predicted maintenance dose requirements for Hmong versus East Asians.


Assuntos
Povo Asiático , Varfarina , Adulto , Algoritmos , Povo Asiático/genética , Genótipo , Humanos , Varfarina/administração & dosagem
20.
Biochem Biophys Res Commun ; 526(3): 772-779, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32265028

RESUMO

Recent evidence suggests that Propionibacterium acnes (P. acnes) is a novel pathogenic factor promoting intervertebral disc degeneration (IVDD), however, whose mechanism remains unclear. A key component of inflammatory responses to P. acnes appears to be interleukin (IL)-1ß, which has been proved to be high expression in degenerative nucleus pulposus cells (NPCs). This study aimed to explore the inflammatory mechanism driving the host response to P. acnes infection in IVDD. Our data demonstrated that the number of nod-like receptor protein 3 (NLRP3)-positive cells was significantly increased in the P. acnes-infected nucleus pulposus (NP) tissue. Meanwhile, the up-regulated expressions of NLRP3, caspase-1, caspase-5, IL-1ß, IL-18, Gasdermin D (GSDMD) were observed in NPCs after co-culturing with P. acnes, which suggested NPCs pyroptosis activation induced by P. acnes. To further investigate the underlying mechanisms, NLRP3 inflammasome inhibitor MCC950 and thioredoxin binding protein (TXNIP)-siRNA were used. With the addition of MCC950 to NPCs co-cultured with P. acnes in vitro, the secretions of mature IL-1ß and IL-18 were reduced. Moreover, these MCC950-mediated effects were repeated by siRNA-transfected TXNIP knockdown. These results implied P. acnes activated inflammatory response by the TXNIP-NLRP3 pathway. To further reveal the anti-degeneration role of MCC950 in vivo, MCC950 was injected into the rabbit IVDD models infected by P. acnes. The MRI and histological detection provided more solid evidence that MCC950 treatment effectively retarded the degenerative process of the intervertebral discs in vivo. In summary, these results suggest that P. acnes-induced NPCs pyroptosis activation via the NLRP3-dependent pathway is likely responsible for the inflammatory pathology of IVDD. MCC950 can alleviate inflammatory injury and NPCs pyroptosis under P. acnes infection and may delay the progression of disc degeneration, which provides a new direction for the treatment of IVDD.


Assuntos
Degeneração do Disco Intervertebral/tratamento farmacológico , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Núcleo Pulposo/metabolismo , Propionibacterium acnes/metabolismo , Piroptose/fisiologia , Adulto , Idoso , Animais , Proteínas de Transporte/metabolismo , Caspases/metabolismo , Linhagem Celular , Modelos Animais de Doenças , Desenho de Fármacos , Furanos , Compostos Heterocíclicos de 4 ou mais Anéis/metabolismo , Humanos , Indenos , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Disco Intervertebral/metabolismo , Pessoa de Meia-Idade , Núcleo Pulposo/citologia , Proteínas de Ligação a Fosfato/metabolismo , Coelhos , Transdução de Sinais , Sulfonamidas , Sulfonas/metabolismo
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