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1.
BMC Plant Biol ; 24(1): 453, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789944

RESUMO

BACKGROUND: Impatiens is an important genus with rich species of garden plants, and its distribution is extremely extensive, which is reflected in its diverse ecological environment. However, the specific mechanisms of Impatiens' adaptation to various environments and the mechanism related to lignin remain unclear. RESULTS: Three representative Impatiens species,Impatiens chlorosepala (wet, low degree of lignification), Impatiens uliginosa (aquatic, moderate degree of lignification) and Impatiens rubrostriata (terrestrial, high degree of lignification), were selected and analyzed for their anatomical structures, lignin content and composition, and lignin-related gene expression. There are significant differences in anatomical parameters among the stems of three Impatiens species, and the anatomical structure is consistent with the determination results of lignin content. Furthermore, the thickness of the xylem and cell walls, as well as the ratio of cell wall thickness to stem diameter have a strong correlation with lignin content. The anatomical structure and degree of lignification in Impatiens can be attributed to the plant's growth environment, morphology, and growth rate. Our analysis of lignin-related genes revealed a negative correlation between the MYB4 gene and lignin content. The MYB4 gene may control the lignin synthesis in Impatiens by controlling the structural genes involved in the lignin synthesis pathway, such as HCT, C3H, and COMT. Nonetheless, the regulation pathway differs between species of Impatiens. CONCLUSIONS: This study demonstrated consistency between the stem anatomy of Impatiens and the results obtained from lignin content and composition analyses. It is speculated that MYB4 negatively regulates the lignin synthesis in the stems of three Impatiens species by regulating the expression of structural genes, and its regulation mechanism appears to vary across different Impatiens species. This study analyses the variations among different Impatiens plants in diverse habitats, and can guide further molecular investigations of lignin biosynthesis in Impatiens.


Assuntos
Impatiens , Lignina , Caules de Planta , Lignina/metabolismo , Caules de Planta/genética , Caules de Planta/anatomia & histologia , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/metabolismo , Impatiens/genética , Impatiens/metabolismo , Impatiens/crescimento & desenvolvimento , Ecossistema , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Adaptação Fisiológica/genética , Regulação da Expressão Gênica de Plantas , Especificidade da Espécie , Genes de Plantas , Parede Celular/metabolismo , Parede Celular/genética
2.
J Biol Chem ; 298(5): 101818, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35278432

RESUMO

Gonadal white adipose tissue (gWAT) can regulate gametogenesis via modulation of neuroendocrine signaling. However, the effect of gWAT on the local microenvironment of the gonad was largely unknown. Herein, we ruled out that gWAT had a neuroendocrine effect on gonad function through a unilateral lipectomy strategy, in which cutting off epididymal white adipose tissue could reduce seminiferous tubule thickness and decrease sperm counts only in the adjacent testis and epididymis of the affected gonad. Consistent with the results in males, in females, ovary mass was similarly decreased by lipectomy. We determined that the defects in spermatogenesis were mainly caused by augmented apoptosis and decreased proliferation of germ cells. Transcriptome analysis suggested that lipectomy could disrupt immune privilege and activate immune responses in both the testis and ovary on the side of the lipectomy. In addition, lipidomics analysis in the testis showed that the levels of lipid metabolites such as free carnitine were elevated, whereas the levels of glycerophospholipids such as phosphatidylcholines and phosphatidylethanolamines were decreased, which indicated that the metabolic niche was also altered. Finally, we show that supplementation of phosphatidylcholine and phosphatidylethanolamine could partially rescue the observed phenotype. Collectively, our findings suggest that gWAT is important for gonad function by not only affecting whole-body homeostasis but also via maintaining local metabolic and immune niches.


Assuntos
Tecido Adiposo Branco , Gônadas , Tecido Adiposo/metabolismo , Tecido Adiposo Branco/metabolismo , Animais , Epididimo , Feminino , Masculino , Camundongos , Espermatogênese , Testículo/metabolismo
3.
Hepatology ; 76(6): 1660-1672, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35596926

RESUMO

BACKGROUND AND AIMS: Hepatocellular carcinoma (HCC) represents the third leading cause of cancer-related mortality in the world. Over the past two decades, there has been minimal improvement in therapies as well as clinical outcomes for patients with Barcelona Clinic Liver Cancer (BCLC)-B. These patients are treated with local interventions, including transarterial chemoembolization. Current methodologies only allow sustained intratumoral release measured in hours. Methodologies to allow sustained local release of the drug cargo over days to weeks are acutely needed. We hypothesize that tumor response as well as outcomes of patients with BCLC-B can be improved through utilization of a highly cytotoxic agent delivered with a sustained release platform. APPROACH AND RESULTS: High-throughput drug screening across 40 HCC patient-derived organoids identified bortezomib (BTZ) as a highly cytotoxic small molecule for HCC. We designed and manufactured sustained release BTZ nanoparticles (BTZ-NP) using a flash nanocomplexation/nanoprecipitation process. We quantified the release profile and tested the anti-tumoral effects in vivo. The BTZ-NP formulation demonstrated a sustained release of BTZ of 30 days. This BTZ-NP formulation was highly effective in controlling tumor size and improved survival in vivo in three animal models of HCC, including when delivered via the hepatic artery, as we envision its delivery in patients. In addition, the BTZ-NP formulation was superior to treatment with doxorubicin-drug eluting beads. CONCLUSIONS: The BTZ-NP formulation provides a potent and safe treatment of HCC via a localized delivery approach. These results warrant additional preclinical studies to advance this technology to human clinical trials.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Nanopartículas , Animais , Humanos , Bortezomib/uso terapêutico , Neoplasias Hepáticas/patologia , Preparações de Ação Retardada/uso terapêutico , Antibióticos Antineoplásicos , Antineoplásicos/uso terapêutico
4.
Chemistry ; 29(38): e202300598, 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37062699

RESUMO

Multifunctional materials with working temperatures near room temperature are crucial for practical applications. Until now, it is still a great challenge to obtain such materials. In this paper, a complex of (C5 NH13 Cl)2 MnBr4 (1) with a structural phase transition near room temperature is reported. The phase transition induces switchable magnetic properties, dielectric anomalies and luminescent response over the same range of temperatures. It is the first time the synergetic effect of magnetism, dielectricity and luminescence near room temperature have been observed in the same molecular complex.


Assuntos
Luminescência , Magnetismo , Temperatura , Transição de Fase
5.
Dis Colon Rectum ; 66(3): 425-433, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35499985

RESUMO

BACKGROUND: Perianal Crohn's disease is associated with poor outcomes and high medical costs. It is notoriously difficult to treat despite therapeutic advancements for luminal disease. A large animal model that mimics human perianal disease is needed to test innovative therapies. OBJECTIVE: This study aimed to create a swine model that replicates the inflammatory component and therapeutic challenges found in patients with perianal Crohn's disease. DESIGN: This was an animal preclinical study. SETTINGS: The experiments were performed at the animal laboratory at the Johns Hopkins University. PATIENTS: Four sus scrufus female pigs were included in the study. INTERVENTIONS: Four female pigs underwent creation of 3 surgical perianal fistulas each, 1 rectovaginal and 2 perianal. Size 24 French setons were placed to maintain patency of the fistula tracts for 4 weeks. After removal of the setons, trinitrobenzene sulfonic acid was administered into the fistula tract to create and maintain local inflammation mimicking perianal Crohn's disease. MAIN OUTCOMES MEASURES: An MRI was obtained to assess the fistulas and the pigs were euthanized to review histopathology. RESULTS: Three inflammatory chronic fistula tracts were successfully created in each pig as confirmed by MRI and examination under anesthesia. This is the first report of maintaining patent fistulas in swine 2 weeks after removal of setons. For the first time, we reported that 2 pigs developed branching fistulas and small abscesses reminiscent of human perianal Crohn's disease. The corresponding histopathologic examination found significant chronic active inflammation on standard hematoxylin and eosin staining. LIMITATIONS: The fistulas were surgically induced and did not occur naturally. CONCLUSIONS: A chronic perianal fistula model in pigs that strongly resembles human perianal Crohn's disease was successfully created. This model can be used to test novel therapeutics and techniques to pave the path for human trials. See Video Abstract at http://links.lww.com/DCR/B969 . UN NUEVO MODELO PORCINO SIMILAR A UN PACIENTE DE LA ENFERMEDAD DE CROHN PERIANAL ANTECEDENTES: La enfermedad de Crohn perianal se asocia con malos resultados y altos costos médicos. Es notoriamente difícil de tratar a pesar de los avances terapéuticos para la enfermedad luminal. Se precisa de un modelo animal grande que imite la enfermedad perianal humana para probar terapias innovadoras.OBJETIVO:Nuestro objetivo de este estudio fue crear un modelo porcino que replique el componente inflamatorio y los desafíos terapéuticos que se encuentran en los pacientes con enfermedad de Crohn perianal.DISEÑO:Este fue un estudio preclínico en animales.AJUSTES:Los experimentos se realizaron en el laboratorio de animales de la Universidad Johns Hopkins.PACIENTES:Se incluyeron en el estudio cuatro cerdas sus scrofa.INTERVENCIONES:Cuatro cerdas fueron sometidas a la creación de 3 fístulas perianales quirúrgicas cada una: 1 recto vaginal y 2 perianales. Se colocaron sedales de 24 French para mantener la permeabilidad de los trayectos fistulosos durante 4 semanas. Tras el retiro de los sedales, se administró ácido trinitrobenceno sulfónico en el trayecto de la fístula para crear y mantener la inflamación local simulando la enfermedad de Crohn perianal.PRINCIPALES MEDIDAS DE RESULTADOS:Se obtuvo una resonancia magnética para evaluar las fístulas y los cerdos fueron sacrificados para revisar la histopatología.RESULTADOS:Se crearon de manera exitosa tres trayectos fistulosos inflamatorios crónicos en cada cerdo, confirmados por imágenes de resonancia magnética y examen bajo anestesia. Este es el primer informe de preservación de fístulas permeables en cerdos 2 semanas tras el retiro de los setones. Por primera vez, informamos que dos cerdos desarrollaron fístulas ramificadas y pequeños abscesos que recuerdan a la enfermedad de Crohn perianal humana. El examen histopatológico correspondiente encontró una significativa inflamación crónica activa en la tinción estándar de hematoxilina y eosina.LIMITACIONES:Las fístulas se indujeron quirúrgicamente y no se produjeron de forma natural.CONCLUSIONES:Se logro recrear con éxito un modelo de fístula perianal crónica en cerdos que se asemeja mucho a la enfermedad de Crohn perianal humana. Este modelo se puede utilizar para probar nuevas terapias y técnicas para allanar el camino para los ensayos en humanos. Consulte Video Resumen en http://links.lww.com/DCR/B969 . (Traducción-Dr Osvaldo Gauto).


Assuntos
Doença de Crohn , Fístula Retal , Animais , Feminino , Doença de Crohn/complicações , Doença de Crohn/cirurgia , Inflamação , Pacientes , Fístula Retal/etiologia , Fístula Retal/cirurgia , Estudos Retrospectivos , Suínos
6.
BMC Plant Biol ; 22(1): 553, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36456926

RESUMO

BACKGROUND: Spur, a structure capable of producing and storing nectar, not only plays a vital role in the pollination process but also promotes the rapid diversification of some plant lineages, which is considered a key innovation in plants. Spur is the focus of many studies, such as evolution and ecological hypothesis, but the current understanding of spur development is limited. High-throughput sequencing of Impatiens uliginosa was carried out to study the molecular mechanism of its spur development, which is believed to provide some insights into the spur development of Impatiens. RESULTS: Transcriptomic sequencing and analysis were performed on spurs and limbs of I. uliginosa at three developmental stages. A total of 47.83 Gb of clean data were obtained, and 49,716 unigene genes were assembled. After comparison with NR, Swiss-Prot, Pfam, COG, GO and KEGG databases, a total of 27,686 genes were annotated successfully. Through comparative analysis, 19,356 differentially expressed genes were found and enriched into 208 GO terms and 146 KEGG pathways, among which plant hormone signal transduction was the most significantly enriched pathway. One thousand thirty-two transcription factors were identified, which belonged to 33 TF families such as MYB, bHLH and TCP. Twenty candidate genes that may be involved in spur development were screened and verified by qPCR, such as SBP, IAA and ABP. CONCLUSIONS: Transcriptome data of different developmental stages of spurs were obtained, and a series of candidate genes related to spur development were identified. The importance of genes related to cell cycle, cell division, cell elongation and hormones in spur development was clarified. This study provided valuable information and resources for understanding the molecular mechanism of spur development in Impatiens.


Assuntos
Impatiens , Transcriptoma , Sequenciamento do Exoma , Ciclo Celular , Bases de Dados de Proteínas
7.
Small ; 18(36): e2202309, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35948487

RESUMO

Functional microgels are preferred stem cell carriers due to the ease of delivery through minimally invasive injection and seamless integration with the surrounding host tissue. A biostimulatory nanofiber-hydrogel composite (NHC) has been previously developed through covalently crosslinking a hyaluronic acid hydrogel network with surface-functionalized poly (ε-caprolactone) nanofiber fragments. The NHC mimics the microarchitecture of native soft tissue matrix, showing enhanced cell infiltration, immunomodulation, and proangiogenic properties. Here, injectability of the pre-formed NHC is improved by mechanical fragmentation, making it into micro-fragmented NHC (mfNHC) in a granular gel form as a stem cell carrier to deliver mesenchymal stem cells (MSCs) for soft tissue remodeling. The mfNHC shows a similar storage modulus but a significantly reduced injection force, as compared with the corresponding bulk NHC. When injected subcutaneously in a rat model, mfNHC-MSC constructs initiate an elevated level of host macrophage infiltration, more pro-regenerative polarization, and subsequently, improved angiogenesis and adipogenesis response when compared to mfNHC alone. A similar trend of host cell infiltration and pro-angiogenic response is detected in a swine model with a larger volume injection. These results suggest a strong potential for use of the mfNHC as an injectable carrier for cell delivery and soft tissue remodeling.


Assuntos
Células-Tronco Mesenquimais , Nanofibras , Animais , Ácido Hialurônico , Hidrogéis , Injeções , Células-Tronco Mesenquimais/fisiologia , Ratos , Suínos , Engenharia Tecidual/métodos
8.
Neoplasma ; 69(5): 1029-1040, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35652621

RESUMO

The study was performed to ascertain the mechanism of sodium butyrate (NaB) mediating the proliferative and invasive properties of oral squamous cell carcinoma (OSCC) cells. The cell proliferative, migrating, and invasive potentials were detected by CCK-8, colony formation, EdU, and Transwell assays. The expression of proliferation- and invasion-related proteins, HDAC1, and HSPB7 in OSCC cells were evaluated by western blot. Immunofluorescence was also performed to evaluate the HDAC1 expression. The enrichment of histone deacetylase HDAC1 in the promoter region of HSPB7 was assessed by the ChIP assay. In vivo growth of OSCC cells was measured by tumorigenesis in nude mice (n=18). The t-test was employed for comparisons of data between the two groups. One-way ANOVA was utilized for comparisons of data among multiple groups, and repeated-measures ANOVA for comparisons of data at different time points among groups, followed by Bonferroni post-hoc test. The data showed that HDAC1 expression was highly upregulated in OSCC cells compared to human normal oral keratinocytes (HNOKs) (p<0.0001), and NaB diminished the HDAC1 expression in OSCC cells. NaB restricted OSCC cell proliferative, migrating, and invasive capabilities by downregulating HDAC1. HSPB7 expression was downregulated in OSCC cells versus HNOKs (p<0.0001). HDAC1 inversely orchestrated the HSPB7 expression in OSCC cells through histone deacetylation modification, and NaB augmented the HSPB7 expression by inhibiting HDAC1. Moreover, NaB inhibited OSCC cell growth in vivo by elevating HSPB7 levels through the HDAC1 repression. In conclusion, NaB restrained cell proliferation and invasion in OSCC cells via HSPB7 upregulation by decreasing the HDAC1 expression.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , MicroRNAs , Neoplasias Bucais , Animais , Ácido Butírico/farmacologia , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Proteínas de Choque Térmico HSP27/metabolismo , Histona Desacetilase 1 , Histona Desacetilases/metabolismo , Histonas , Humanos , Camundongos , Camundongos Nus , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/genética , Sincalida/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço
9.
Proc Natl Acad Sci U S A ; 116(26): 12710-12719, 2019 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-31182572

RESUMO

Despite significant research efforts, clinical practice for arterial bypass surgery has been stagnant, and engineered grafts continue to face postimplantation challenges. Here, we describe the development and application of a durable small-diameter vascular graft with tailored regenerative capacity. We fabricated small-diameter vascular grafts by electrospinning fibrin tubes and poly(ε-caprolactone) fibrous sheaths, which improved suture retention strength and enabled long-term survival. Using surface topography in a hollow fibrin microfiber tube, we enable immediate, controlled perfusion and formation of a confluent endothelium within 3-4 days in vitro with human endothelial colony-forming cells, but a stable endothelium is noticeable at 4 weeks in vivo. Implantation of acellular or endothelialized fibrin grafts with an external ultrathin poly(ε-caprolactone) sheath as an interposition graft in the abdominal aorta of a severe combined immunodeficient Beige mouse model supports normal blood flow and vessel patency for 24 weeks. Mechanical properties of the implanted grafts closely approximate the native abdominal aorta properties after just 1 week in vivo. Fibrin mediated cellular remodeling, stable tunica intima and media formation, and abundant matrix deposition with organized collagen layers and wavy elastin lamellae. Endothelialized grafts evidenced controlled healthy remodeling with delayed and reduced macrophage infiltration alongside neo vasa vasorum-like structure formation, reduced calcification, and accelerated tunica media formation. Our studies establish a small-diameter graft that is fabricated in less than 1 week, mediates neotissue formation and incorporation into the native tissue, and matches the native vessel size and mechanical properties, overcoming main challenges in arterial bypass surgery.


Assuntos
Materiais Biocompatíveis/química , Endotélio Vascular/fisiologia , Regeneração , Enxerto Vascular/métodos , Animais , Artérias/fisiologia , Artérias/cirurgia , Feminino , Fibrina/química , Camundongos , Poliésteres/química , Fluxo Sanguíneo Regional , Engenharia Tecidual/métodos
10.
BMC Surg ; 22(1): 211, 2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35655200

RESUMO

OBJECTIVES: To evaluate the feasibility and advantages of wedge resection plus transverse suture without mesentery detached approach applied to loop ileostomy closure by analyzing the surgical data and the incidence of postoperative complications of patients undergoing this procedure. METHODS: We performed a retrospective analysis of the hospitalization data of patients who underwent ileostomy closure surgery and met the research standards from January 2017 to April 2021 in Guangxi Medical University Cancer Hospital; all surgeries were performed by the same surgeon. The perioperative data were statistically analyzed by grouping. RESULTS: In total, 65 patients were enrolled in this study, with 12 in the wedge resection group, 35 in the stapler group, and 18 in the hand suture group. There was no significant difference in operation time between the wedge resection group and stapler group (P > 0.05), but both groups had shorter operation time than that in the hand suture group (P < 0.05). The postoperative exhaustion time of wedge resection group was earlier than that of the others, and cost of surgical consumables in the wedge resection group was significantly lower than that in the stapler group, all with statistically significant differences (P < 0.05). By contrast, there were no statistically significant differences in postoperative complication incidences among the three groups. CONCLUSIONS: The wedge resection plus transverse suture without mesentery detached approach is safe and easy for closure of loop ileostomy in selected patients, and the intestinal motility recovers rapidly postoperatively. It costs less surgical consumables, and is particularly suitable for the currently implemented Diagnosis-Related Groups payment method.


Assuntos
Ileostomia , Complicações Pós-Operatórias , China , Estudos de Viabilidade , Humanos , Ileostomia/métodos , Mesentério/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos
11.
Nano Lett ; 21(13): 5697-5705, 2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34228937

RESUMO

Polyelectrolyte complex particles assembled from plasmid DNA (pDNA) and poly(ethylenimine) (PEI) have been widely used to produce lentiviral vectors (LVVs) for gene therapy. The current batch-mode preparation for pDNA/PEI particles presents limited reproducibility in large-scale LVV manufacturing processes, leading to challenges in tightly controlling particle stability, transfection outcomes, and LVV production yield. Here we identified the size of pDNA/PEI particles as a key determinant for a high transfection efficiency with an optimal size of 400-500 nm, due to a cellular-uptake-related mechanism. We developed a kinetics-based approach to assemble size-controlled and shelf-stable particles using preassembled nanoparticles as building blocks and demonstrated production scalability on a scale of at least 100 mL. The preservation of colloidal stability and transfection efficiency was benchmarked against particles generated using an industry standard protocol. This particle manufacturing method effectively streamlines the viral manufacturing process and improves the production quality and consistency.


Assuntos
DNA , Polietilenoimina , DNA/genética , Tamanho da Partícula , Plasmídeos/genética , Reprodutibilidade dos Testes , Transfecção
12.
Mater Today (Kidlington) ; 42: 99-116, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34421329

RESUMO

Advances in nanoformulation have driven progress in biomedicine by producing nanoscale tools for biosensing, imaging, and drug delivery. Flash-based technology, the combination of rapid mixing technique with the self-assembly of macromolecules, is a new engine for the translational nanomedicine. Here, we review the state-of-the-art in flash-based self-assembly including theoretical and experimental principles, mixing device design, and applications. We highlight the fields of flash nanocomplexation (FNC) and flash nanoprecipitation (FNP), with an emphasis on biomedical applications of FNC, and discuss challenges and future directions for flash-based nanoformulation in biomedicine.

13.
Nano Lett ; 20(9): 6420-6428, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32813534

RESUMO

Inspired by the superlubricated surface (SLS) of ice, which consists of an ultrathin and contiguous layer of surface-bound water, we built a SLS on the polycaprolactone (PCL)/poly(2-methacryloxyethylphosphorylcholine) (PMPC) composite nanofibrous membrane via electrospinning under controlled relative humidity (RH). The zwitterionic PMPC on the nanofiber provided a surface layer of bound water, thus generating a hydration lubrication surface. Prepared under 20% RH, electrospun PCL/PMPC nanofibers reached a minimum coefficient of friction (COF) of about 0.12 when the weight ratio of PMPC to PCL was 0.1. At a higher RH, a SLS with an ultralow COF of less than 0.05 was formed on the composite nanofibers. The high stability of the SLS hydration layer on the engineered nanofibrous membrane effectively inhibited fibroblast adhesion and markedly reduced tissue adhesion during tendon repair in vivo. This work demonstrates the great potential of this ice-inspired SLS approach in tissue adhesion-prevention applications.


Assuntos
Nanofibras , Fibroblastos/patologia , Humanos , Membranas Artificiais , Poliésteres , Tendões/patologia , Aderências Teciduais/patologia , Aderências Teciduais/prevenção & controle , Engenharia Tecidual , Alicerces Teciduais
14.
Nano Lett ; 20(9): 6289-6298, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32594746

RESUMO

T cells are critical players in disease; yet, their antigen-specificity has been difficult to identify, as current techniques are limited in terms of sensitivity, throughput, or ease of use. To address these challenges, we increased the throughput and translatability of magnetic nanoparticle-based artificial antigen presenting cells (aAPCs) to enrich and expand (E+E) murine or human antigen-specific T cells. We streamlined enrichment, expansion, and aAPC production processes by enriching CD8+ T cells directly from unpurified immune cells, increasing parallel processing capacity of aAPCs in a 96-well plate format, and designing an adaptive aAPC that enables multiplexed aAPC construction for E+E and detection. We applied these adaptive platforms to process and detect CD8+ T cells specific for rare cancer neoantigens, commensal bacterial cross-reactive epitopes, and human viral and melanoma antigens. These innovations dramatically increase the multiplexing ability and decrease the barrier to adopt for investigating antigen-specific T cell responses.


Assuntos
Nanopartículas , Neoplasias , Animais , Células Apresentadoras de Antígenos , Linfócitos T CD8-Positivos , Epitopos , Humanos , Camundongos
15.
J Integr Plant Biol ; 63(7): 1324-1340, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33605510

RESUMO

Mitogen-activated protein kinases (MPKs) play essential roles in guard cell signaling, but whether MPK cascades participate in guard cell ethylene signaling and interact with hydrogen peroxide (H2 O2 ), nitric oxide (NO), and ethylene-signaling components remain unclear. Here, we report that ethylene activated MPK3 and MPK6 in the leaves of wild-type Arabidopsis thaliana as well as ethylene insensitive2 (ein2), ein3, nitrate reductase1 (nia1), and nia2 mutants, but this effect was impaired in ethylene response1 (etr1), nicotinamide adenine dinucleotide phosphate oxidase AtrbohF, mpk kinase1 (mkk1), and mkk3 mutants. By contrast, the constitutive triple response1 (ctr1) mutant had constitutively active MPK3 and MPK6. Yeast two-hybrid, bimolecular fluorescence complementation, and pull-down assays indicated that MPK3 and MPK6 physically interacted with MKK1, MKK3, and the C-terminal region of EIN2 (EIN2 CEND). mkk1, mkk3, mpk3, and mpk6 mutants had typical levels of ethylene-induced H2 O2 generation but impaired ethylene-induced EIN2 CEND cleavage and nuclear translocation, EIN3 protein accumulation, NO production in guard cells, and stomatal closure. These results show that the MKK1/3-MPK3/6 cascade mediates ethylene-induced stomatal closure by functioning downstream of ETR1, CTR1, and H2 O2 to interact with EIN2, thereby promoting EIN3 accumulation and EIN3-dependent NO production in guard cells.


Assuntos
Proteínas de Arabidopsis/metabolismo , Proteínas de Ligação a DNA/metabolismo , Etilenos/farmacologia , MAP Quinase Quinase 1/metabolismo , MAP Quinase Quinase 3/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Estômatos de Plantas/efeitos dos fármacos , Estômatos de Plantas/metabolismo , Receptores de Superfície Celular/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Ligação a DNA/genética , MAP Quinase Quinase 1/genética , MAP Quinase Quinase 3/genética , Proteínas Quinases Ativadas por Mitógeno/genética , Receptores de Superfície Celular/genética , Fatores de Transcrição/genética
16.
Mol Pharm ; 17(3): 757-768, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-32011888

RESUMO

Salmon calcitonin (sCT) is a potent calcium-regulating peptide hormone and widely applied for the treatment of some bone diseases clinically. However, the therapeutic usefulness of sCT is hindered by the frequent injection required, owing to its short plasma half-life and therapeutic need for a high dose. Oral delivery is a popular modality of administration for patients because of its convenience to self-administration and high patient compliance, while orally administered sCT remains a great challenge currently due to the existence of multiple barriers in the gastrointestinal (GI) tract. Here, we introduced an orally targeted delivery system to increase the transport of sCT across the intestine through both the paracellular permeation route and the bile acid pathway. In this system, sCT-based glycol chitosan-taurocholic acid conjugate (GC-T)/dextran sulfate (DS) ternary nanocomplexes (NC-T) were produced by a flash nanocomplexation (FNC) process in a kinetically controlled mode. The optimized NC-T exhibited well-controlled properties with a uniform and sub-60 nm hydrodynamic diameter, high batch-to-batch reproducibility, good physical or chemical stability, as well as sustained drug release behaviors. The studies revealed that NC-T could effectively improve the intestinal uptake and permeability, owing to its surface functionalization with the taurocholic acid ligand. In the rat model, orally administered NC-T showed an obvious hypocalcemia effect and a relative oral bioavailability of 10.9%. An in vivo assay also demonstrated that NC-T induced no observable side effect after long-term oral administration. As a result, the orally targeted nanocomplex might be a promising candidate for improving the oral transport of therapeutic peptides.


Assuntos
Calcitonina/administração & dosagem , Hormônios e Agentes Reguladores de Cálcio/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Absorção Intestinal/efeitos dos fármacos , Nanocompostos/química , Administração Oral , Animais , Disponibilidade Biológica , Transporte Biológico , Células CACO-2/efeitos dos fármacos , Células CACO-2/metabolismo , Calcitonina/efeitos adversos , Calcitonina/sangue , Calcitonina/farmacocinética , Cálcio/sangue , Hormônios e Agentes Reguladores de Cálcio/efeitos adversos , Hormônios e Agentes Reguladores de Cálcio/sangue , Hormônios e Agentes Reguladores de Cálcio/farmacocinética , Quitosana/química , Sulfato de Dextrana/química , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Meia-Vida , Humanos , Hipocalcemia/induzido quimicamente , Injeções Subcutâneas , Masculino , Ratos , Ratos Sprague-Dawley , Ácido Taurocólico/química
17.
Arch Microbiol ; 202(7): 1939-1944, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32451593

RESUMO

One motile strain designated, YIM DR1026T was isolated from the roots of Psammosilene tunicoides collected from Gejiu, Yunnan province, China. The cells of strain YIM DR1026T were Gram-negative and short-rod shaped. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain YIM DR1026T was a member of the genus Aureimonas and closely related to Aureimonas rubiginis (96.7%). DNA-DNA relatedness values between strain YIM 1026T and Aureimonas rubiginis BCRC 80440T was 38.2 ± 1.5%. The ANI value between YIM DR1026T and other Aureimonas members were below the cut-off level (95-96%) recommended as the average nucleotide identity (ANI) criterion for interspecies identity. Strain YIM DR1026T grew at 4-30 °C (optimum 28 °C), pH 4.0-9.0 (optimum pH 6.0-7.0) and tolerated NaCl (w/v) up to 1% (optimum 0%). Q-10 was sole the respiratory ubiquinone present in YIM DR1026T. Polar lipids of strain YIM DR1026T were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine, sulfoquinovosyldiacylglycerol, unidentified aminolipid and unidentified polar lipid. The genomic G + C content was 64.6 mol%. The major fatty acids were C18:1ω7c, C16:0 and summed feature 3 (C16:1ω7c/C16:1ω6c). Based on phenotypic, phylogenetic, chemotaxonomic and genome comparison, strain YIM DR1026T represents a novel species of the genus Aureimonas, for which the name Aureimonas psammosilene sp. nov. is proposed. The type strain is YIM DR1026T (= KCTC 42691T = NBRC 112412T).


Assuntos
Alphaproteobacteria/classificação , Caryophyllaceae/microbiologia , Filogenia , Raízes de Plantas/microbiologia , Alphaproteobacteria/genética , Alphaproteobacteria/isolamento & purificação , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/análise , Fosfolipídeos/análise , RNA Ribossômico 16S/genética , Especificidade da Espécie
18.
J Appl Toxicol ; 40(10): 1396-1409, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32418265

RESUMO

Polychlorinated biphenyls (PCBs) are a class of persistent organic environmental pollutants with a total of 209 homologs. The homolog 2,3',4,4',5-pentachlorobiphenyl (PCB118) is one of the most important dioxin-like PCBs and is highly toxic. PCB118 can accumulate in human tissues, serum and breast milk, which leads to direct exposure of the fetus during development. In the present study, pregnant mice were exposed to 0, 20 and 100 µg/kg/day of PCB118 during the stage of fetal primordial germ cell migration. Compared with the control group, we found morphological alterations of the seminiferous tubules and a higher sperm deformity rate in the male offspring in the treatment groups. Furthermore, the methylation patterns in the treatment groups of the imprinted genes H19 and Gtl2 in the sperm were altered in the male offspring. We also characterized the disturbance of the expression levels of DNA methyltransferase 1 (Dnmt1), Dnmt3a, Dnmt3b, Dnmt3l, and Uhrf1. The results indicated that intrauterine exposure to low doses of PCB118 could significantly damage the reproductive health of the male offspring. Therefore, attention should be paid to the adverse effects of PCB118 exposure during pregnancy on the reproductive system of male offspring.


Assuntos
Poluentes Ambientais/toxicidade , Epigênese Genética/efeitos dos fármacos , Genitália/efeitos dos fármacos , Bifenilos Policlorados/toxicidade , Efeitos Tardios da Exposição Pré-Natal , Espermatozoides/efeitos dos fármacos , Útero/efeitos dos fármacos , Animais , Feminino , Masculino , Exposição Materna/efeitos adversos , Camundongos , Modelos Animais , Gravidez
19.
Biochem Biophys Res Commun ; 516(2): 558-564, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31235253

RESUMO

Electrospinning methods can generate scaffolds with alignment cues to guide the development of myogenic precursors into 3D skeletal muscle grafts. However, cells seeded onto these scaffolds adhere to the exterior resulting in regions of acellularity within the scaffold interior. To overcome this limitation, we modified an aqueous solution-electrospinning method to encapsulate C2C12s and electrospin them into fibrin/polyethylene oxide (PEO) microfiber bundles. We demonstrated that loading C2C12s as cellular aggregates (80-90 µm in diameter) and modifying several other electrospinning parameters dramatically increased cell viability following exposure to the 4.5 kV electric field. C2C12-seeded fibrin/PEO microfiber bundles were cultured for up to seven days. Uninduced and myogenically induced C2C12s proliferated, elongated and became multinucleated. Myogenic induction increased the number of myotube-associated nuclei (36.4 ±â€¯12% vs. 6.2 ±â€¯1.9%), myotube length (122.4 ±â€¯10.9 µm vs. 59.9 ±â€¯8.3 µm), and myotube diameter (16.76 ±â€¯2.06 µm vs. 12.49 ±â€¯0.93 µm). The data presented in this study demonstrates for the first time that cells can be loaded inside the aligned fibrin hydrogel 3D construct during aqueous solution electrospinning while retaining their potential for de novo tissue formation.


Assuntos
Fibrina/química , Desenvolvimento Muscular , Engenharia Tecidual/métodos , Animais , Agregação Celular , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Sobrevivência Celular , Camundongos , Fibras Musculares Esqueléticas/metabolismo , Alicerces Teciduais/química
20.
Biomacromolecules ; 20(1): 528-538, 2019 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-30537806

RESUMO

Oral drug delivery is a more favored mode of administration because of its ease of administration, high patient compliance, and low healthcare costs. However, no oral protein formulations are commercially available currently due to hostile gastrointestinal (GI) barriers resulting in insignificant oral bioavailability of macromolecular drugs. Herein, we used insulin as a model protein drug; insulin-loaded N-(2-hydroxy)-propyl-3-trimethylammonium chloride modified chitosan (HTCC)/sodium tripolyphosphate (TPP) nanocomplex (NC) as a nanocore was further encapsulated into enteric Eudragit L100-55 material, through a two-step flash nanocomplexation (FNC) process in a reliable and scalable manner, forming our NC-in-Eudragit composite particles (NE). Particle size and surface properties of our optimized NE were tailored to protect the loaded insulin from acidic degradation in the hostile stomach environment and to achieve intestinal site-specific drug release as well as the improvement of oral delivery efficiency of insulin. In addition, the oral administration of the optimized NE to type 1 diabetic rats could induce a very significant hypoglycemic effect with a relative oral bioavailability of 13.3%. Our results demonstrated that enteric encapsulation of nanotherapeutics using a FNC apparatus could cause drug formulations to possess better size controllability, batch-mode reproducibility, and homogeneous surface coating and then significantly enhance their oral bioavailability of insulin, indicating its great potential for clinical translation of oral protein therapeutics.


Assuntos
Absorção Gastrointestinal , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Nanocápsulas/química , Resinas Acrílicas/química , Administração Oral , Animais , Células CACO-2 , Quitosana/análogos & derivados , Células HT29 , Humanos , Hipoglicemiantes/farmacocinética , Insulina/farmacocinética , Masculino , Nanocápsulas/efeitos adversos , Polifosfatos/química , Ratos , Ratos Sprague-Dawley
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