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1.
Nat Immunol ; 20(8): 1059-1070, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31308541

RESUMO

Dysfunction of virus-specific CD4+ T cells in chronic human infections is poorly understood. We performed genome-wide transcriptional analyses and functional assays of CD4+ T cells specific for human immunodeficiency virus (HIV) from HIV-infected people before and after initiation of antiretroviral therapy (ART). A follicular helper T cell (TFH cell)-like profile characterized HIV-specific CD4+ T cells in viremic infection. HIV-specific CD4+ T cells from people spontaneously controlling the virus (elite controllers) robustly expressed genes associated with the TH1, TH17 and TH22 subsets of helper T cells. Viral suppression by ART resulted in a distinct transcriptional landscape, with a reduction in the expression of genes associated with TFH cells, but persistently low expression of genes associated with TH1, TH17 and TH22 cells compared to the elite controller profile. Thus, altered differentiation is central to the impairment of HIV-specific CD4+ T cells and involves both gain of function and loss of function.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Expressão Gênica/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Células Th1/patologia , Células Th17/patologia , Perfilação da Expressão Gênica , Infecções por HIV/virologia , Humanos , Receptores CXCR5/metabolismo , Células Th1/citologia , Células Th1/imunologia , Células Th17/citologia , Células Th17/imunologia , Carga Viral/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
2.
Immunity ; 51(5): 915-929.e7, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31732167

RESUMO

The elicitation of broadly neutralizing antibodies (bNAbs) against the HIV-1 envelope glycoprotein (Env) trimer remains a major vaccine challenge. Most cross-conserved protein determinants are occluded by self-N-glycan shielding, limiting B cell recognition of the underlying polypeptide surface. The exceptions to the contiguous glycan shield include the conserved receptor CD4 binding site (CD4bs) and glycoprotein (gp)41 elements proximal to the furin cleavage site. Accordingly, we performed heterologous trimer-liposome prime:boosting in rabbits to drive B cells specific for cross-conserved sites. To preferentially expose the CD4bs to B cells, we eliminated proximal N-glycans while maintaining the native-like state of the cleavage-independent NFL trimers, followed by gradual N-glycan restoration coupled with heterologous boosting. This approach successfully elicited CD4bs-directed, cross-neutralizing Abs, including one targeting a unique glycan-protein epitope and a bNAb (87% breadth) directed to the gp120:gp41 interface, both resolved by high-resolution cryoelectron microscopy. This study provides proof-of-principle immunogenicity toward eliciting bNAbs by vaccination.


Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Lipossomos , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Animais , Linfócitos B/imunologia , Linfócitos B/metabolismo , Antígenos CD4/química , Antígenos CD4/imunologia , Antígenos CD4/metabolismo , Complemento C3/imunologia , Complemento C3/metabolismo , Apresentação Cruzada/imunologia , Epitopos/imunologia , Glicosilação , Infecções por HIV/virologia , Humanos , Imunoglobulina G/imunologia , Modelos Moleculares , Testes de Neutralização , Polissacarídeos/imunologia , Polissacarídeos/metabolismo , Ligação Proteica , Conformação Proteica , Coelhos , Produtos do Gene env do Vírus da Imunodeficiência Humana/administração & dosagem , Produtos do Gene env do Vírus da Imunodeficiência Humana/química , Produtos do Gene env do Vírus da Imunodeficiência Humana/metabolismo
3.
Environ Res ; 246: 118144, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38191043

RESUMO

Soil degradation has become a major global problem owing to the rapid development of agriculture. The problems of soil drought and decreased soil fertility caused by soil degradation severely affect the development of the agricultural and forestry industries. In this study, we designed sodium alginate (SA)/sodium lignosulfonate (SLS) hydrogel based on the activation and crosslinking of inert Ca2+. CaCO3 and SA were mixed, and then, inert Ca2+ was activated to prepare a gel with a stable structure and a uniform interior and exterior. The crosslinking activated by inert Ca2+ enhanced the stability of the hydrogel, and the optimal swelling rate of the hydrogel reached 28.91 g/g, thereby effectively improving the water-holding capacity of the soil (77.6-108.83 g/kg). SLS was degraded into humic acid (HA) and gradually released, demonstrating a positive growth-promoting effect in plant growth experiments. The SA/SLS hydrogel can be used for soil water retention and mitigation to significantly decrease the water loss rate of soil. This study will assist in addressing soil drought and fertility loss.


Assuntos
Conservação dos Recursos Hídricos , Hidrogéis , Lignina/análogos & derivados , Hidrogéis/química , Alginatos/química , Solo/química , Água/química , Sódio
4.
BMC Gastroenterol ; 22(1): 27, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35057742

RESUMO

BACKGROUND: Although marginal donor livers expand the donor pool, an ideal method for quantitatively evaluating the quality of donor livers has not been developed. This study aimed to explore the feasibility of indocyanine green (ICG) fluorescence imaging for estimating liver function in an ischemia-reperfusion model. METHODS: Forty-eight rats were randomly and evenly divided into 8 groups: the control group and the experimental groups (I-VII). The portal vein blocking period was 0 min, 10 min, 20 min, 30 min, 40 min, 50 min and 60 min. After blood flow was reestablished and the hemodynamics stabilized, ICG was injected through the dorsal penile vein as a bolus, and the fluorescence signal was recorded for 30 min in real time. The fluorescence intensity (FI) curve of the liver was fitted with an asymptotic regression model. Fresh liver tissues and serum were obtained from the middle lobe of the liver on postoperative day (POD) 1 and POD 7 for histopathological evaluation and liver function tests. RESULTS: The growth rate of the FI curve, parameter b3, decreased from groups I to VII. According to the two sudden changes in b3 (20 min, 50 min), the experimental groups could be classified into 3 groups (A, B and C). Hepatocytes in groups I-II showed slight edema, group III began to show obvious hepatocyte edema and vacuolar degeneration, and in groups VI-VII, severe hepatocyte degeneration, necrosis and large inflammatory cell infiltration were observed. Suzuki's scores in the 3 groups were also significantly different (P < 0.01). At the same time, the serum liver function in the experimental groups showed a significant increase on POD 1 and a decrease on POD 7. The alanine aminotransferase (ALT), aspartate aminotransferase (AST), and total bilirubin (TB) levels of groups A, B, and C were significantly different on POD 1 (P < 0.05), and the ALT and direct bilirubin (DB) levels were significantly different on POD 7 (P < 0.05); the lactic dehydrogenase (LDH) level of the group C was significantly higher than that of the groups A and B on POD 1 and POD 7. Meanwhile, the 7-day survival rate of the rats in group C was poor compared to that of the rats in groups A and B (58.3% vs. 100% vs. 100%). CONCLUSION: ICG fluorescence imaging is effective for estimating the degree of liver damage and grading in an ischemia-reperfusion model. It probably has the potential for use in assessing the quality of the donor liver in liver transplantation.


Assuntos
Verde de Indocianina , Transplante de Fígado , Animais , Humanos , Isquemia , Doadores Vivos , Imagem Óptica , Ratos , Reperfusão
5.
Int J Mol Sci ; 23(5)2022 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-35269996

RESUMO

Plants are always exposed to the environment, polluted by multiple trace elements. Hydrogen sulfide (H2S), an endogenous gaseous transmitter in plant cells, can help plant combat single elements with excess concentration. Until now, little has been known about the regulatory role of H2S in response to combined stress of multiple elements. Here we found that combined exposure of mercury (Hg) and selenium (Se) triggered endogenous H2S signal in the roots of Brasscia rapa. However, neither Hg nor Se alone worked on it. In roots upon Hg + Se exposure, the defensive role of endogenous H2S was associated to the decrease in reactive oxygen species (ROS) level, followed by alleviating cell death and recovering root growth. Such findings extend our knowledge of plant H2S in response to multiple stress conditions.


Assuntos
Brassica rapa , Sulfeto de Hidrogênio , Mercúrio , Selênio , Brassica rapa/metabolismo , Sulfeto de Hidrogênio/metabolismo , Mercúrio/toxicidade , Raízes de Plantas/metabolismo , Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Selênio/metabolismo
6.
J Cell Physiol ; 236(7): 5373-5386, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33368292

RESUMO

CXCL6, contraction of C-X-C motif chemokine ligand 6, whose biological roles have been rarely described in esophageal squamous cell carcinoma (ESCC). To understand the clinicopathological and biological roles played by CXCL6 in the growth and metastasis of ESCC, immunohistochemistry was used to detect the expression of CXCL6 in ESCC tissues, totaling 105 cases; and the correlation was statistically analyzed between CXCL6 expression and clinicopathological parameters. The role mediated in migration and invasion was evaluated using wound-healing and Transwell assays. MTT and flow cytometry were used to assay the proliferative variation. In vivo, tail vein injection model was established in nude mice xenografted with human ESCC cell lines whose CXCL6 were artificially manipulated. It was found that relative to normal control, CXCL6 was profoundly higher in ESCC; upregulated CXCL6 only significantly correlated with differentiation degree. In vitro, CXCL6 was found to promote the proliferation, migration, and invasion of ESCC cells; which was fully corroborated by nude mice experiment that CXCL6 can promote the growth and metastases of ESCC cells in vivo. Mechanistically, CXCL6 was discovered to be capable of promoting epithelial-mesenchymal transition and upregulating PD-L1 expression through activation of the STAT3 pathway. Collectively, all the data we showed here demonstrate that CXCL6 can enhance the growth and metastases of ESCC cells both in vivo and in vitro.


Assuntos
Antígeno B7-H1/metabolismo , Quimiocina CXCL6/metabolismo , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Fator de Transcrição STAT3/metabolismo , Animais , Proliferação de Células , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/metabolismo , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , Invasividade Neoplásica/patologia , Transdução de Sinais/fisiologia , Regulação para Cima
7.
Cancer Cell Int ; 21(1): 121, 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33602237

RESUMO

BACKGROUND: Calmodulin1 (CALM1) has been identified as one of the overexpression genes in a variety of cancers and EGFR inhibitor have been widely used in clinical treatment but it is unknown whether CALM1 and epidermal growth factor receptor (EGFR) have a synergistic effect in esophageal squamous cell carcinoma (ESCC). The aim of the present study was to explore the synergistic effects of knock-out CALM1 combined with EGFR inhibitor (Afatinib) and to elucidate the role of CALM1 in sensitizing the resistance to Afatinib in ESCC. METHOD: Immunohistochemistry (IHC) and qRT-PCR were used to examine the expression of CALM1 and EGFR in ESCC tissues. Kaplan-Meier survival analysis was used to analyze the clinical and prognostic significance of CALM1 and EGFR expression in ESCC. Furthermore, to evaluate the biological function of CALM1 in ESCC, the latest gene editing technique CRISPR/Cas9(Clustered regularly interspaced short palindromic repeats)was applied to knockout CALM1 in ESCC cell lines KYSE150, Eca109 and TE-1. MTT, flow cytometry, Transwell migration, scratch wound-healing and colony formation assays were performed to assay the combined effect of knock-out CALM1 and EGFR inhibitor on ESCC cell proliferation and migration. In addition, nude mice xenograft model was used to observe the synergistic inhibition of knock-out CALM1 and Afatinib. RESULTS: Both CALM1 and EGFR were found to be significantly over-expressed in ESCC compared with paired normal control. Over-expressed CALM1 and EGFR were significantly associated with clinical stage, T classification and poor overall prognosis, respectively. In vitro, the combined effect of knock-out CALM1 mediated by the lentivirus and EGFR inhibitor was shown to be capable of inhibiting the proliferation, inducing cell cycle arrest at G1/S stage and increasing apoptosis of KYSE-150 and Eca109 cells; invasion and migration were also suppressed. In vivo, the results of tumor weight and total fluorescence were markedly reduced compared with the sgCtrl-infected group and sgCAML1 group. CONCLUSION: Our data demonstrated that knock-out of CALM1 could sensitize ESCC cells to EGFR inhibitor, and it may exert oncogenic role via promotion of EMT. Taken together, CALM1 may be a tempting target to overcome Afatinib resistance.

8.
Biochem Biophys Res Commun ; 526(1): 29-34, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32192776

RESUMO

NME4, also named Nm23-H4, is a contraction of NME/NM23 Nucleoside Diphosphate Kinase 4, whose major role is the synthesis of nucleoside triphosphates. However, its association with programmed death ligand 1 (PD-L1) remains far from understood. Herein, it was discovered that silencing NME4 can lead to the marked downregulation of PD-L1, with phosphorylated STAT3 at the 705th serine being inactivated in vitro in esophageal squamous cell carcinoma (ESCC) cell lines. To further validate the association between NME4 and PD-L1 that was observed in cell lines, Pearson correlation analysis was performed on the data regarding the transcriptomic RNA sequencing of NME4 and PD-L1 in cervical squamous cell carcinoma (CSCC), which pathologically highly resembles ESCC in terms of tumor origin, obtained from the GEPIA database. It was demonstrated that their correlation was significant but negative between NME4 and PD-L1 in CSCC. To the best of our knowledge, this is the first report describing a modulation exerted by NME4 over PD-L1 in the background of squamous cell carcinoma, strongly suggestive of the underlying role of NME4 working to exclude CD8 T cells from infiltrating into the squamous cell carcinoma microenvironment.


Assuntos
Antígeno B7-H1/metabolismo , Carcinoma de Células Escamosas/metabolismo , Nucleosídeo Difosfato Quinase D/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Antígeno B7-H1/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Regulação para Baixo , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/metabolismo , Carcinoma de Células Escamosas do Esôfago/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcriptoma/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia
9.
Mol Cell Biochem ; 471(1-2): 81-89, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32504364

RESUMO

NME4, also designated nm23-H4 or NDPK-D, has been known for years for its well-established roles in the synthesis of nucleoside triphosphates, though; little has been known regarding the differential metabolites involved as well as the biological roles NME4 plays in proliferation and invasion of esophageal squamous cell carcinoma (ESCC) cells. To understand the biological roles of NME4 in ESCC cells, lentiviral-based short hairpin RNA interference (shRNA) vectors were constructed and used to stably knock down NME4. Then, the proliferative and invasive variations were assessed using MTT, Colony formation and Transwell assays. To understand the metabolites involved after silencing of NME4 in ESCC cells, widely targeted metabolomic screening was taken. It was discovered that silencing of NME4 can profoundly suppress the proliferation and invasion in ESCC cells in vitro. Metabolically, a total of 11 differential metabolites were screened. KEGG analyses revealed that Tryptophan, Riboflavin, Purine, Nicotinate, lysine degradation, and Linoleic acid metabolism were also involved in addition to the well-established nucleotides metabolism. Some of these differential metabolites, say, 2-Picolinic Acid, Nicotinic Acid and Pipecolinic Acid were suggested to be associated with tumor immunomodulation. The data we described here support the idea that metabolisms occurred in mitochondrial was closely related to tumor immunity.


Assuntos
Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/metabolismo , Regulação Neoplásica da Expressão Gênica , Metaboloma , Mitocôndrias/metabolismo , Nucleosídeo Difosfato Quinase D/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Humanos , Mitocôndrias/patologia , Invasividade Neoplásica , Nucleosídeo Difosfato Quinase D/antagonistas & inibidores , Nucleosídeo Difosfato Quinase D/genética
10.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(12): 1256-1260, 2020 Dec.
Artigo em Zh | MEDLINE | ID: mdl-33327994

RESUMO

OBJECTIVE: To study the association of fatty acid composition in human milk with breast milk jaundice (BMJ) in neonates. METHODS: A total of 30 full-term neonates who were admitted to the neonatal intensive care unit from October 2016 to October 2017 and were diagnosed with late-onset BMJ were enrolled as the BMJ group. Thirty healthy neonates without jaundice or pathological jaundice who were admitted to the confinement center during the same period of time were enrolled as the control group. Related clinical data were collected, including sex, mode of birth, feeding pattern, gestational age, birth weight, gravida, parity, and peak level of total serum bilirubin. Breast milk was collected from the mothers, and the MIRIS human milk analyzer was used to measure macronutrients (fat, protein, and carbohydrate) and calorie. Gas chromatography was used to analyze the content of different fatty acids in breast milk. RESULTS: The control group had higher levels of macronutrients in human milk than the BMJ group, with significant differences in fat, dry matter, and calorie (P < 0.05). In addition, 25 fatty acids were detected in breast milk, including 9 saturated fatty acids, 6 monounsaturated fatty acids, and 10 polyunsaturated fatty acids. The comparison of the percentage composition of different fatty acids showed that compared with the control group, the BMJ group had significantly lower percentage compositions of C15:0, C16:0, C17:0, C18:0, C20:0, C18:1n9t, C20:1n9, C18:3n6, C22:2, and C22:6n3 (DHA) and higher percentage compositions of C10:0, C12:0, C14:0 in breast milk (P < 0.05). CONCLUSIONS: Some macronutrients and fatty acid composition in human milk may be associated with the pathogenesis of BMJ in neonates.


Assuntos
Ácidos Graxos/análise , Icterícia Neonatal/etiologia , Leite Humano/química , Estudos de Casos e Controles , Feminino , Humanos , Recém-Nascido , Nutrientes/análise , Gravidez
11.
J Sci Food Agric ; 99(8): 4082-4093, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30761554

RESUMO

BACKGROUND: Selenium (Se)-induced phytotoxicity has been linked to oxidative injury triggered by the accumulation of reactive oxygen species (ROS) due to the disturbance of anti-oxidative systems. However, the way Se stress induces hydrogen peroxide (H2 O2 ) production in plants is a long-standing question. Here we identified the role of polyamine oxidase (PAO) in H2 O2 production in the root of Brassica rapa upon Se stress. RESULTS: Studying Se-induced growth inhibition, H2 O2 accumulation, and oxidative injury in the root of Brassica rapa, we found that excessive Se exposure resulted in a remarkable increase in PAO activity. Inhibition of PAO activity led to decreased H2 O2 content and alleviated oxidative injury in the Se-treated root. These results indicated that Se stress induced PAO-dependent H2 O2 production. A total of six BrPAO family members were discovered in the genome of B. rapa by in silico analysis. Se stress pronouncedly upregulated the expression of most BrPAOs and further transient expression analysis proved that it could lead to H2 O2 production. CONCLUSION: These results suggest that Se stress upregulates the expression of a set of BrPAOs which further enhances PAO activity, contributing to H2 O2 generation in roots. © 2019 Society of Chemical Industry.


Assuntos
Brassica rapa/genética , Peróxido de Hidrogênio/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/metabolismo , Proteínas de Plantas/metabolismo , Selênio/metabolismo , Brassica rapa/enzimologia , Brassica rapa/crescimento & desenvolvimento , Brassica rapa/metabolismo , Regulação da Expressão Gênica de Plantas , Estresse Oxidativo , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/genética , Proteínas de Plantas/genética , Espécies Reativas de Oxigênio/metabolismo , Poliamina Oxidase
12.
BMC Genomics ; 19(1): 717, 2018 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-30261913

RESUMO

BACKGROUND: Arabidopsis pumila is native to the desert region of northwest China and it is extraordinarily well adapted to the local semi-desert saline soil, thus providing a candidate plant system for environmental adaptation and salt-tolerance gene mining. However, understanding of the salt-adaptation mechanism of this species is limited because of genomic sequences scarcity. In the present study, the transcriptome profiles of A. pumila leaf tissues treated with 250 mM NaCl for 0, 0.5, 3, 6, 12, 24 and 48 h were analyzed using a combination of second-generation sequencing (SGS) and third-generation single-molecule real-time (SMRT) sequencing. RESULTS: Correction of SMRT long reads by SGS short reads resulted in 59,328 transcripts. We found 8075 differentially expressed genes (DEGs) between salt-stressed tissues and controls, of which 483 were transcription factors and 1157 were transport proteins. Most DEGs were activated within 6 h of salt stress and their expression stabilized after 48 h; the number of DEGs was greatest within 12 h of salt stress. Gene annotation and functional analyses revealed that expression of genes associated with the osmotic and ionic phases rapidly and coordinately changed during the continuous salt stress in this species, and salt stress-related categories were highly enriched among these DEGs, including oxidation-reduction, transmembrane transport, transcription factor activity and ion channel activity. Orphan, MYB, HB, bHLH, C3H, PHD, bZIP, ARF and NAC TFs were most enriched in DEGs; ABCB1, CLC-A, CPK30, KEA2, KUP9, NHX1, SOS1, VHA-A and VP1 TPs were extensively up-regulated in salt-stressed samples, suggesting that they play important roles in slat tolerance. Importantly, further experimental studies identified a mitogen-activated protein kinase (MAPK) gene MAPKKK18 as continuously up-regulated throughout salt stress, suggesting its crucial role in salt tolerance. The expression patterns of the salt-responsive 24 genes resulted from quantitative real-time PCR were basically consistent with their transcript abundance changes identified by RNA-Seq. CONCLUSION: The full-length transcripts generated in this study provide a more accurate depiction of gene transcription of A. pumila. We identified potential genes involved in salt tolerance of A. pumila. These data present a genetic resource and facilitate better understanding of salt-adaptation mechanism for ephemeral plants.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Perfilação da Expressão Gênica/métodos , Cloreto de Sódio/farmacologia , Arabidopsis/efeitos dos fármacos , Proteínas de Arabidopsis/efeitos dos fármacos , China , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Redes Reguladoras de Genes , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Salinidade , Análise de Sequência de RNA , Estresse Fisiológico
13.
J Virol ; 87(3): 1899-905, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23152526

RESUMO

PG9 and PG16 are two quaternary-structure-specific broadly neutralizing antibodies with unique HCDR3 subdomains. Previously, we showed that glycosylphosphatidylinositol (GPI)-anchored HCDR3 subdomains (GPI-HCDR3) can be targeted to lipid rafts of the plasma membrane, bind to the epitope recognized by HCDR3 of PG16, and neutralize diverse HIV-1 isolates. In this study, we further developed trimeric GPI-HCDR3s and demonstrated that trimeric GPI-HCDR3 (PG16) dramatically improves anti-HIV-1 neutralization, suggesting that a stoichiometry of recognition of 3 or 2 HCDR3 molecules (PG16) to 1 viral spike is possible.


Assuntos
Anticorpos Neutralizantes/farmacologia , Anticorpos Anti-HIV/farmacologia , Inibidores da Fusão de HIV/farmacologia , HIV-1/fisiologia , Internalização do Vírus/efeitos dos fármacos , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/farmacologia , Anticorpos Neutralizantes/genética , Glicosilfosfatidilinositóis/metabolismo , Anticorpos Anti-HIV/genética , HIV-1/efeitos dos fármacos
14.
ACS Appl Mater Interfaces ; 16(1): 584-593, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38112556

RESUMO

Currently, the primary bottlenecks that hinder the widespread application of supercapacitors are low energy density and narrow potential windows. Herein, the hybrid supercapacitor with high energy density and wide potential window is constructed via an in situ self-assembly method employing RGO-induced flower-like MOF(Ni). Benefiting from the synergistic effect between RGO and MOF(Ni), the interfacial interactions are effectively improved, and the contact area with the electrolyte is enhanced, which increases the ion transfer kinetics and overall electrochemical performance. The MOF(Ni)@RGO electrode exhibits a specific capacitance of 1267.73 F g-1 at a current density of 1 A g-1. Crucially, the assembled MOF(Ni)@RGO//BC with a broad potential window and good stability employing a MOF(Ni)@RGO anode and biomass carbon cathode, combined with a 2 M PVA-KOH gel-electrolyte, achieves a maximum energy density of 70.16 Wh kg-1 at a power density of 2200.09 W kg-1, outperforming most reported supercapacitors. This hybrid supercapacitor exhibits excellent stability and high energy density, providing a novel strategy for further large-scale applications.

15.
J Vis Exp ; (204)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38407239

RESUMO

Liver transplantation is the primary treatment for end-stage liver disease. However, the shortage and inadequate quality of donor organs necessitate the development of alternative therapies. Bioartificial livers (BALs) utilizing decellularized liver matrix (DLM) have emerged as promising solutions. However, sourcing suitable DLMs remains challenging. The use of a decellularized spleen matrix (DSM) has been explored as a foundation for BALs, offering a readily available alternative. In this study, rat spleens were harvested and decellularized using a combination of freeze-thaw cycles and perfusion with decellularization reagents. The protocol preserved the microstructures and components of the extracellular matrix (ECM) within the DSM. The complete decellularization process took approximately 11 h, resulting in an intact ECM within the DSM. Histological analysis confirmed the removal of cellular components while retaining the ECM's structure and composition. The presented protocol provides a comprehensive method for obtaining DSM, offering potential applications in liver tissue engineering and cell therapy. These findings contribute to the development of alternative approaches for the treatment of end-stage liver disease.


Assuntos
Doença Hepática Terminal , Baço , Animais , Ratos , Terapia Baseada em Transplante de Células e Tecidos , Matriz Extracelular
16.
Front Bioeng Biotechnol ; 12: 1331078, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38328445

RESUMO

Background: Small-diameter (<6 mm) artificial vascular grafts (AVGs) are urgently required in vessel reconstructive surgery but constrained by suboptimal hemocompatibility and the complexity of anastomotic procedures. This study introduces coaxial electrospinning and magnetic anastomosis techniques to improve graft performance. Methods: Bilayer poly(lactide-co-caprolactone) (PLCL) grafts were fabricated by coaxial electrospinning to encapsulate heparin in the inner layer for anticoagulation. Magnetic rings were embedded at both ends of the nanofiber conduit to construct a magnetic anastomosis small-diameter AVG. Material properties were characterized by micromorphology, fourier transform infrared (FTIR) spectra, mechanical tests, in vitro heparin release and hemocompatibility. In vivo performance was evaluated in a rabbit model of inferior vena cava replacement. Results: Coaxial electrospinning produced PLCL/heparin grafts with sustained heparin release, lower platelet adhesion, prolonged clotting times, higher Young's modulus and tensile strength versus PLCL grafts. Magnetic anastomosis was significantly faster than suturing (3.65 ± 0.83 vs. 20.32 ± 3.45 min, p < 0.001) and with higher success rate (100% vs. 80%). Furthermore, magnetic AVG had higher short-term patency (2 days: 100% vs. 60%; 7 days: 40% vs. 0%) but similar long-term occlusion as sutured grafts. Conclusion: Coaxial electrospinning improved hemocompatibility and magnetic anastomosis enhanced implantability of small-diameter AVG. Short-term patency was excellent, but further optimization of anticoagulation is needed for long-term patency. This combinatorial approach holds promise for vascular graft engineering.

17.
Int J Surg ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38954664

RESUMO

BACKGROUND: Liver failure remains a critical clinical challenge with limited treatment options. Cross-circulation, the establishment of vascular connections between individuals, has historically been explored as a potential supportive therapy but with limited success. This study investigated the feasibility of combining cross-circulation with a rapidly deployable veno-venous bypass (VVB) graft for multi-organ support in a rat model of total hepatectomy, representing the most severe form of liver failure. MATERIALS AND METHODS: A Y-shaped VVB graft was fabricated using coaxial electrospinning of PLCL/heparin nanofibers and magnetic rings for rapid anastomosis. After total hepatectomy in rats, the VVB graft was implanted to divert blood flow. Cross-circulation was then established between anhepatic and normal host rats. Hemodynamics, biochemical parameters, blood gases, and survival were analyzed across three groups: hepatectomy with blocked vessels (block group), hepatectomy with VVB only (VVB group), and hepatectomy with VVB and cross-circulation (VVB/cross-circulation group). RESULTS: The VVB graft exhibited suitable mechanical properties and hemocompatibility. VVB rapidly restored hemodynamic stability and mitigated abdominal congestion post-hepatectomy. Cross-circulation further ameliorated liver dysfunction, metabolic derangements, and coagulation disorders in anhepatic rats, significantly prolonging survival compared to the VVB group (mean 6.56±0.58 vs 4.05±0.51 h, P<0.05) and the block group (mean 1.01±0.05 h, P<0.05). CONCLUSION: Combining cross-circulation with a rapidly deployed VVB graft provided effective multi-organ biosystemic support in a rat model of total hepatectomy, substantially improving the biochemical status and survival time. This approach holds promise for novel liver failure therapies and could facilitate liver transplantation procedures.

18.
J Virol ; 86(14): 7662-76, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22553333

RESUMO

The development of a successful vaccine against human immunodeficiency virus type 1 (HIV-1) likely requires immunogens that elicit both broadly neutralizing antibodies against envelope spikes and T cell responses that recognize multiple viral proteins. HIV-1 virus-like particles (VLP), because they display authentic envelope spikes on the particle surface, may be developed into such immunogens. However, in one way or the other current systems for HIV-1 VLP production have many limitations. To overcome these, in the present study we developed a novel strategy to produce HIV-1 VLP using stably transfected Drosophila S2 cells. We cotransfected S2 cells with plasmids encoding HIV-1 envelope, Gag, and Rev proteins and a selection marker. After stably transfected S2 clones were established, HIV-1 VLP and their immunogenicity in mice were carefully evaluated. Here, we report that HIV-1 envelope proteins are properly cleaved, glycosylated, and incorporated into VLP with Gag. The amount of VLP released into culture supernatants is comparable to those produced by insect cells infected with recombinant baculoviruses. Moreover, cryo-electron microscopy tomography revealed average 17 spikes per purified VLP, and antigenic epitopes on the spikes were recognized by the broadly neutralizing antibodies 2G12, b12, VRC01, and 4E10 but not by PG16. Finally, mice primed with DNA and boosted with VLP in the presence of CpG exhibited anti-envelope antibody responses, including ELISA-binding, neutralizing, antibody-dependent cell-mediated cytotoxicity and antibody-dependent cell-mediated viral inhibition, as well as envelope and Gag-specific CD8 T cell responses. Thus, we conclude that HIV-1 VLP produced by the S2 expression system has many desirable features to be developed into a vaccine component against HIV-1.


Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Anti-HIV/imunologia , HIV-1/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Citotoxicidade Celular Dependente de Anticorpos , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular , Drosophila melanogaster , Células HEK293 , Anticorpos Anti-HIV/sangue , Humanos , Camundongos , Oligonucleotídeos Fosforotioatos/imunologia , Transfecção , Produtos do Gene env do Vírus da Imunodeficiência Humana/química , Produtos do Gene gag do Vírus da Imunodeficiência Humana/química
19.
Medicine (Baltimore) ; 102(49): e36381, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38065912

RESUMO

RATIONALE: Wilms' tumor (WT) is the most common pediatric kidney malignancy and is rarely found in adults. Nonspecific clinical symptoms and imaging features often lead to delayed diagnosis or misdiagnosis of adult WT, resulting in poor clinical outcomes. Ultrasound (US), as an efficient and noninvasive examination method, has been widely used in clinical diagnosis and treatment. Therefore, various US evidence is meaningful to improve understanding of adult WT characteristics in ultrasound. PATIENT CONCERNS: A 45-year-old female patient with uremia (regular hemodialysis for 13 years) with painless gross hematuria was diagnosed with a right kidney tumor penetrating to the lung. Preoperatively, B-mode ultrasonography showed an ill-defined hyperechoic mass in the right kidney, which revealed an unclear border, uneven internal echoes, and calcification. Besides, the internal blood flow signal of the tumor was detected. Contrast-enhanced ultrasound (CEUS) showed an uneven hyper-enhancement in the tumor ("fast in and slow out"). Contrast-enhanced computed tomography of the kidney indicated a similar result as the CEUS. Moreover, the chest CT identified multiple pulmonary metastatic nodules. DIAGNOSES: An ultrasound-guided percutaneous core needle biopsy of the tumor proceeded to make a definite diagnosis of adult WT (epithelial type). INTERVENTIONS: The patient was treated with tislelizumab. OUTCOMES: No progress was found to date. LESSONS: We report the first case in which CEUS was performed in an adult WT patient with uremia and multiple pulmonary metastases. The features obtained by the US can help in the diagnosis of adult WT and direct further diagnostic procedures.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Uremia , Tumor de Wilms , Feminino , Humanos , Pessoa de Meia-Idade , Meios de Contraste , Neoplasias Renais/complicações , Neoplasias Renais/diagnóstico por imagem , Ultrassonografia/métodos , Uremia/complicações , Uremia/diagnóstico por imagem , Uremia/terapia , Tumor de Wilms/complicações , Tumor de Wilms/diagnóstico por imagem
20.
Foods ; 12(18)2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37761167

RESUMO

Gray mold infected with Botrytis cinerea frequently appears on fruits and vegetables throughout the supply chain after harvest, leading to economic losses. Biological control of postharvest disease with phytochemicals is a promising approach. CA (cinnamaldehyde) is a natural phytochemical with medicinal and antimicrobial activity. This study evaluated the effect of CA in controlling B. cinerea on fresh pepper fruit. CA inhibited B. cinerea growth in vitro significantly in a dose- (0.1-0.8 mM) and time-dependent (6-48 h) manner, with an EC50 (median effective concentration) of 0.5 mM. CA induced the collapse and breakdown of the mycelia. CA induced lipid peroxidation resulting from ROS (reactive oxygen species) accumulation in mycelia, further leading to cell leakage, evidenced by increased conductivity in mycelia. CA induced mycelial glycerol accumulation, resulting in osmotic stress possibly. CA inhibited sporulation and spore germination resulting from ROS accumulation and cell death observed in spores. Spraying CA at 0.5 mM induced a defense response in fresh pepper fruits, such as the accumulation of defense metabolites (flavonoid and total phenols) and an increase in the activity of defense enzymes (PAL, phenylalanine ammonia lyase; PPO, polyphenol oxidase; POD, peroxidase). As CA is a type of environmentally friendly compound, this study provides significant data on the activity of CA in the biocontrol of postharvest gray mold in peppers.

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