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1.
Nat Commun ; 15(1): 4330, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773072

RESUMO

The Hendra and Nipah viruses (HNVs) are highly pathogenic pathogens without approved interventions for human use. In addition, the interaction pattern between the attachment (G) and fusion (F) glycoproteins required for virus entry remains unclear. Here, we isolate a panel of Macaca-derived G-specific antibodies that cross-neutralize HNVs via multiple mechanisms. The most potent antibody, 1E5, confers adequate protection against the Nipah virus challenge in female hamsters. Crystallography demonstrates that 1E5 has a highly similar binding pattern to the receptor. In cryo-electron microscopy studies, the tendency of 1E5 to bind to the upper or lower heads results in two distinct quaternary structures of G. Furthermore, we identify the extended outer loop ß1S2-ß1S3 of G and two pockets on the apical region of fusion (F) glycoprotein as the essential sites for G-F interactions. This work highlights promising drug candidates against HNVs and contributes deeper insights into the viruses.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Microscopia Crioeletrônica , Infecções por Henipavirus , Proteínas Virais de Fusão , Animais , Anticorpos Neutralizantes/imunologia , Feminino , Anticorpos Antivirais/imunologia , Infecções por Henipavirus/virologia , Infecções por Henipavirus/imunologia , Proteínas Virais de Fusão/imunologia , Proteínas Virais de Fusão/química , Humanos , Proteínas do Envelope Viral/imunologia , Proteínas do Envelope Viral/química , Vírus Nipah/imunologia , Internalização do Vírus/efeitos dos fármacos , Henipavirus/imunologia , Cricetinae , Reações Cruzadas/imunologia , Vírus Hendra/imunologia , Macaca , Mesocricetus , Cristalografia por Raios X
2.
Mol Biol Evol ; 40(11)2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37823401

RESUMO

The genus Macaca includes 23 species assigned into 4 to 7 groups. It exhibits the largest geographic range and represents the most successful example of adaptive radiation of nonhuman primates. However, intrageneric phylogenetic relationships among species remain controversial and have not been resolved so far. In this study, we conducted a phylogenomic analysis on 16 newly generated and 8 published macaque genomes. We found strong evidence supporting the division of this genus into 7 species groups. Incomplete lineage sorting (ILS) was the primary factor contributing to the discordance observed among gene trees; however, we also found evidence of hybridization events, specifically between the ancestral arctoides/sinica and silenus/nigra lineages that resulted in the hybrid formation of the fascicularis/mulatta group. Combined with fossil data, our phylogenomic data were used to establish a scenario for macaque radiation. These findings provide insights into ILS and potential ancient introgression events that were involved in the radiation of macaques, which will lead to a better understanding of the rapid speciation occurring in nonhuman primates.


Assuntos
Genoma , Macaca , Animais , Filogenia , Macaca/genética , Hibridização Genética
3.
Front Immunol ; 14: 1239179, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37868993

RESUMO

Introduction: The SARS-CoV-2 Omicron variant has become the dominant SARS-CoV-2 variant and exhibits immune escape to current COVID-19 vaccines, the further boosting strategies are required. Methods: We have conducted a non-randomized, open-label and parallel-controlled phase 4 trial to evaluate the magnitude and longevity of immune responses to booster vaccination with intramuscular adenovirus vectored vaccine (Ad5-nCoV), aerosolized Ad5-nCoV, a recombinant protein subunit vaccine (ZF2001) or homologous inactivated vaccine (CoronaVac) in those who received two doses of inactivated COVID-19 vaccines. Results: The aerosolized Ad5-nCoV induced the most robust and long-lasting neutralizing activity against Omicron variant and IFNg T-cell response among all the boosters, with a distinct mucosal immune response. SARS-CoV-2-specific mucosal IgA response was substantially generated in subjects boosted with the aerosolized Ad5-nCoV at day 14 post-vaccination. At month 6, participants boosted with the aerosolized Ad5-nCoV had remarkably higher median titer and seroconversion of the Omicron BA.4/5-specific neutralizing antibody than those who received other boosters. Discussion: Our findings suggest that aerosolized Ad5-nCoV may provide an efficient alternative in response to the spread of the Omicron BA.4/5 variant. Clinical trial registration: https://www.chictr.org.cn/showproj.html?proj=152729, identifier ChiCTR2200057278.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , SARS-CoV-2 , COVID-19/prevenção & controle , Imunidade nas Mucosas , Anticorpos
4.
PeerJ ; 11: e16066, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37744243

RESUMO

Background: Glycolysis is closely associated with cancer progression and treatment outcomes. However, the role of glycolysis in the immune microenvironment, prognosis, and immunotherapy of glioma remains unclear. Methods: This study investigated the role of glycolysis on prognosis and its relationship with the tumor microenvironment (TME). Subsequently, we developed and validated the glycolysis-related gene signature (GRS)-TME classifier using multiple independent cohorts. Furthermore, we also examined the prognostic value, somatic alterations, molecular characteristics, and potential benefits of immunotherapy based on GRS-TME classifier. Lastly, the effect of kinesin family member 20A (KIF20A) on the proliferation and migration of glioma cells was evaluated in vitro. Results: Glycolysis was identified as a significant prognostic risk factor in glioma, and closely associated with an immunosuppressive microenvironment characterized by altered distribution of immune cells. Furthermore, a personalized GRS-TME classifier was developed and validated by combining the glycolysis (18 genes) and TME (seven immune cells) scores. Patients in the GRSlow/TMEhigh subgroup exhibited a more favorable prognosis compared to other subgroups. Distinct genomic alterations and signaling pathways were observed among different subgroups, which are closely associated with cell cycle, epithelial-mesenchymal transition, p53 signaling pathway, and interferon-alpha response. Additionally, we found that patients in the GRSlow/TMEhigh subgroup exhibit a higher response rate to immunotherapy, and the GRS-TME classifier can serve as a novel biomarker for predicting immunotherapy outcomes. Finally, high expression of KIF20A is associated with an unfavorable prognosis in glioma, and its knockdown can inhibit the proliferation and migration of glioma cells. Conclusions: Our study developed a GRS-TME classifier for predicting the prognosis and potential benefits of immunotherapy in glioma patients. Additionally, we identified KIF20A as a prognostic and therapeutic biomarker for glioma.


Assuntos
Glioma , Microambiente Tumoral , Humanos , Microambiente Tumoral/genética , Prognóstico , Imunoterapia , Glioma/genética , Glicólise/genética
5.
Arch Biochem Biophys ; : 109697, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37481197

RESUMO

Melanoma is a very common malignant tumor with poor prognosis. Herbacetin is a flavonol compound with outstanding anti-tumor effects. Our work investigated the biological effects and mechanism of Herbacetin in melanoma. In our study, the mRNA and protein expressions were assessed using qRT-PCR, Western blot and IHC. MSP was performed to evaluated PGIS promoter methylation level. Cell viability, migration and invasion were examined by MTT assay, transwell migration and invasion assay, respectively. Our results revealed that DNMT3B was markedly upregulated in melanoma, while PGIS was lowly expressed. Herbacetin treatment could not only inhibit the proliferation, migration, invasion of melanoma cells and inhibit the growth of melanoma in vivo. Herbacetin could also restore the abnormal expressions of DNMT3B and PGIS in melanoma cells and tumor tissues. PGIS silencing neutralized the inhibitory effects of Herbacetin on the malignant behaviors of melanoma cells. Besides, DNMT3B knockdown promoted PGIS expression via reducing PGIS promoter methylation level in melanoma cells, thereby inhibiting malignant behaviors of melanoma cells. And as expected, the inhibitory effects of Herbacetin on malignant behaviors of melanoma cells were all abolished by DNMT3B overexpression. Collectively, Herbacetin reduced DNMT3B expression to upregulate PGIS in melanoma cells and participated in suppressing the proliferation, migration, and invasion of melanoma cells.

6.
Food Funct ; 14(10): 4905-4920, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37157847

RESUMO

Atherosclerosis (AS)-induced cardiovascular disease is a leading cause of death worldwide. To date, there is still a lack of effective approaches for AS intervention. Cardamonin (CAD) is a bioactive food component, but its effect on AS is unknown. In this work, CAD was investigated for its effect on AS using low-density lipoprotein receptor knockout mice and tumor necrosis factor-alpha (TNF-α)-stimulated endothelial cells (ECs). After a 12-week intervention, CAD was found to significantly prevent AS formation in the aortic root and aortic tree, reduce the necrotic core area, and inhibit aortic inflammation and oxidative stress. Moreover, CAD quenched TNF-α-provoked inflammation and oxidative stress in ECs. RNA-sequencing identified nuclear factor erythroid-2 related factor 2 (NFE2L2, NRF2)/heme oxidase 1 (HO1) signaling to be drastically activated by CAD. CAD is a known activator of the aryl hydrocarbon receptor (AHR) which is a transcription factor of the NFE2L2 gene. Surprisingly, AHR was not required for CAD's action on the activation of NRF2/HO1 signaling since AHR gene silencing did not reverse this effect. Furthermore, a molecular docking assay showed a strong binding potential of CAD to the Kelch domain of the Kelch-like ECH-associated protein 1 (KEAP1) which sequesters NRF2 in the cytoplasm. Both CAD and the Kelch domain inhibitor Ki696 promoted NRF2 nuclear translocation, whereas the combination of CAD and Ki696 did not yield a greater effect compared with either CAD or Ki696, confirming the interaction of CAD with the Kelch domain. This work provides an experimental basis for CAD as a novel and effective bioactive food component in future AS interventions.


Assuntos
Aterosclerose , Fator 2 Relacionado a NF-E2 , Animais , Camundongos , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Células Endoteliais/metabolismo , Simulação de Acoplamento Molecular , Estresse Oxidativo , Inflamação/metabolismo , Aterosclerose/tratamento farmacológico , Aterosclerose/genética
7.
Viruses ; 14(12)2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36560808

RESUMO

Viruses are strict intracellular parasites that rely on the proteins encoded in their genomes for the effective manipulation of the infected cell that ultimately enables a successful infection. Viral proteins have to be produced during the cell invasion and takeover in sufficient amounts and in a timely manner. Silencing suppressor proteins evolved by plant viruses can boost the production of viral proteins; although, additional mechanisms for the regulation of viral protein production likely exist. The strongest silencing suppressor encoded by the geminivirus tomato yellow leaf curl virus (TYLCV) is V2: V2 suppresses both post-transcriptional and transcriptional gene silencing (PTGS and TGS), activities that are associated with its localization in punctate cytoplasmic structures and in the nucleus, respectively. However, V2 has been previously described to largely localize in the endoplasmic reticulum (ER), although the biological relevance of this distribution remains mysterious. Here, we confirm the association of V2 to the ER in Nicotiana benthamiana and assess the silencing suppression activity-independent impact of V2 on protein accumulation. Our results indicate that V2 has no obvious influence on the localization of ER-synthesized receptor-like kinases (RLKs) or ER quality control (ERQC)/ER-associated degradation (ERAD), but dramatically enhances the accumulation of the viral C4 protein, which is co-translationally myristoylated, possibly in proximity to the ER. By using the previously described V2C84S/86S mutant, in which the silencing suppression activity is abolished, we uncouple RNA silencing from the observed effect. Therefore, this work uncovers a novel function of V2, independent of its capacity to suppress silencing, in the promotion of the accumulation of another crucial viral protein.


Assuntos
Begomovirus , Geminiviridae , Proteínas Virais/metabolismo , Geminiviridae/genética , Geminiviridae/metabolismo , Begomovirus/genética , Begomovirus/metabolismo , Retículo Endoplasmático/metabolismo , Doenças das Plantas , Nicotiana
8.
Signal Transduct Target Ther ; 7(1): 139, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35478188

RESUMO

The SARS-CoV-2 Omicron variant shows substantial resistance to neutralization by infection- and vaccination-induced antibodies, highlighting the demands for research on the continuing discovery of broadly neutralizing antibodies (bnAbs). Here, we developed a panel of bnAbs against Omicron and other variants of concern (VOCs) elicited by vaccination of adenovirus-vectored COVID-19 vaccine (Ad5-nCoV). We also investigated the human longitudinal antibody responses following vaccination and demonstrated how the bnAbs evolved over time. A monoclonal antibody (mAb), named ZWD12, exhibited potent and broad neutralization against SARS-CoV-2 variants Alpha, Beta, Gamma, Kappa, Delta, and Omicron by blocking the spike protein binding to the angiotensin-converting enzyme 2 (ACE2) and provided complete protection in the challenged prophylactic and therapeutic K18-hACE2 transgenic mouse model. We defined the ZWD12 epitope by determining its structure in complex with the spike (S) protein via cryo-electron microscopy. This study affords the potential to develop broadly therapeutic mAb drugs and suggests that the RBD epitope bound by ZWD12 is a rational target for the design of a broad spectrum of vaccines.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Anticorpos Monoclonais/genética , Anticorpos Antivirais , Anticorpos Amplamente Neutralizantes , COVID-19/prevenção & controle , Vacinas contra COVID-19/genética , Microscopia Crioeletrônica , Epitopos , Humanos , Camundongos , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Vacinação , Proteínas do Envelope Viral
9.
Lancet Infect Dis ; 21(12): 1654-1664, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34324836

RESUMO

BACKGROUND: SARS-CoV-2 has caused millions of deaths, and, since Aug 11, 2020, 20 intramuscular COVID-19 vaccines have been approved for use. We aimed to evaluate the safety and immunogenicity of an aerosolised adenovirus type-5 vector-based COVID-19 vaccine (Ad5-nCoV) in adults without COVID-19 from China. METHOD: This was a randomised, single-centre, open-label, phase 1 trial done in Zhongnan Hospital (Wuhan, China), to evaluate the safety and immunogenicity of the Ad5-nCoV vaccine by aerosol inhalation in adults (≥18 years) seronegative for SARS-CoV-2. Breastfeeding or pregnant women and people with major chronic illnesses or history of allergies were excluded. Participants were enrolled and randomly assigned (1:1:1:1:1) into five groups to be vaccinated via intramuscular injection, aerosol inhalation, or both. Randomisation was stratified by sex and age (18-55 years or ≥56 years) using computer-generated randomisation sequences (block sizes of five). Only laboratory staff were masked to group assignment. The participants in the two aerosol groups received an initial high dose (2 × 1010 viral particles; HDmu group) or low dose (1 × 1010 viral particles; LDmu group) of Ad5-nCoV vaccine on day 0, followed by a booster on day 28. The mixed vaccination group received an initial intramuscular (5 × 1010 viral particles) vaccine on day 0, followed by an aerosolised booster (2 × 1010 viral particles) vaccine on day 28 (MIX group). The intramuscular groups received one dose (5 × 1010 viral particles; 1Dim group) or two doses (10 × 1010 viral particles; 2Dim group) of Ad5-nCoV on day 0. The primary safety outcome was adverse events 7 days after each vaccination, and the primary immunogenicity outcome was anti-SARS-CoV-2 spike receptor IgG antibody and SARS-CoV-2 neutralising antibody geometric mean titres at day 28 after last vaccination. This trial is registered with ClinicalTrials.gov, number NCT04552366. FINDINGS: Between Sept 28, 2020, and Sept 30, 2020, 230 individuals were screened for inclusion, of whom 130 (56%) participants were enrolled into the trial and randomly assigned into one of the five groups (26 participants per group). Within 7 days after vaccination, adverse events occurred in 18 (69%) in the HDmu group, 19 (73%) in the LDmu group, 19 (73%) in the MIX group, 19 (73%) in the 1Dim group, and 15 (58%) in the 2Dim group. The most common adverse events reported 7 days after the first or booster vaccine were fever (62 [48%] of 130 participants), fatigue (40 [31%] participants), and headache (46 [35%] participants). More adverse events were reported in participants who received intramuscular vaccination, including participants in the MIX group (49 [63%] of 78 participants), than those who received aerosol vaccine (13 [25%] of 52 participants) after the first vaccine vaccination. No serious adverse events were noted within 56 days after the first vaccine. At days 28 after last vaccination, geometric mean titres of SARS-CoV-2 neutralising antibody was 107 (95% CI 47-245) in the HDmu group, 105 (47-232) in the LDmu group, 396 (207-758) in the MIX group, 95 (61-147) in the 1Dim group, and 180 (113-288) in the 2Dim group. The geometric mean concentrations of receptor binding domain-binding IgG was 261 EU/mL (95% CI 121-563) in the HDmu group, 289 EU/mL (138-606) in the LDmu group, 2013 EU/mL (1180-3435) in the MIX group, 915 EU/mL (588-1423) in the 1Dim group, and 1190 EU/mL (776-1824) in the 2Dim group. INTERPRETATION: Aerosolised Ad5-nCoV is well tolerated, and two doses of aerosolised Ad5-nCoV elicited neutralising antibody responses, similar to one dose of intramuscular injection. An aerosolised booster vaccination at 28 days after first intramuscular injection induced strong IgG and neutralising antibody responses. The efficacy and cost-effectiveness of aerosol vaccination should be evaluated in future studies. FUNDING: National Key Research and Development Programme of China and National Science and Technology Major Project. TRANSLATION: For the Chinese translation of the Summary see Supplementary Material.


Assuntos
Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , SARS-CoV-2/imunologia , Administração por Inalação , Adolescente , Adulto , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19/imunologia , Vacinas contra COVID-19/efeitos adversos , China , Método Duplo-Cego , Feminino , Humanos , Imunidade Celular/imunologia , Esquemas de Imunização , Imunização Secundária , Imunogenicidade da Vacina , Imunoglobulina G/sangue , Injeções Intramusculares , Masculino , Pessoa de Meia-Idade , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinação , Adulto Jovem
10.
Luminescence ; 36(3): 698-704, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33270343

RESUMO

A simple and sensitive colorimetric sensing method was constructed for detection of Hg2+ in aqueous solutions and based on silver nanoparticles functionalized with l-cysteine (l-Cys-Ag NPs). In this method, adenosine triphosphate (ATP) induced aggregation of l-Cys-Ag NPs. Simultaneously, the solution colour changed from bright yellow to brown. In the presence of Hg2+ , Hg2+ chelated ATP to form a complex and reduce the degree of aggregation of l-Cys-Ag NPs and was accompanied by a colour change from brown to bright yellow. The changing values of absorbance at 390 nm were linearly correlated with concentration of Hg2+ over the 4.00 × 10-8 to 1.04 × 10-6 mol·L-1 range, with a detection limit of 8 nM. This method was used successfully for detection of Hg2+ in real water samples and performed good selectivity and sensitivity. The recovery range was 91.5-109.1%, indicating that the method has vast application potential for determination of Hg2+ in the environment.


Assuntos
Mercúrio , Nanopartículas Metálicas , Colorimetria , Cisteína , Prata , Água
11.
Viruses ; 12(3)2020 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-32120864

RESUMO

The Rift Valley fever virus (RVFV) is an arthropod-borne virus that can not only cause severe disease in domestic animals but also in humans. However, the licensed vaccines or available therapeutics for humans do not exist. Here, we report two Gn-specific neutralizing antibodies (NAbs), isolated from a rhesus monkey immunized with recombinant human adenoviruses type 4 expressing Rift Valley fever virus Gn and Gc protein (rHAdV4-GnGcopt). The two NAbs were both able to protect host cells from RVFV infection. The interactions between NAbs and Gn were then characterized to demonstrate that these two NAbs might preclude RVFV glycoprotein rearrangement, hindering the exposure of fusion loops in Gc to endosomal membranes after the virus invades the host cell. The target region for the two NAbs is located in the Gn domain III, implying that Gn is a desired target for developing vaccines and neutralizing antibodies against RVFV.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Febre do Vale de Rift/imunologia , Vírus da Febre do Vale do Rift/imunologia , Proteínas do Envelope Viral/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/química , Anticorpos Antivirais/sangue , Anticorpos Antivirais/química , Linhagem Celular , Ensaio de Imunoadsorção Enzimática , Epitopos , Humanos , Imunização , Macaca mulatta , Modelos Moleculares , Conformação Molecular , Testes de Neutralização , Ligação Proteica , Febre do Vale de Rift/virologia , Relação Estrutura-Atividade , Proteínas do Envelope Viral/química
12.
Biochimie ; 162: 198-207, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31075281

RESUMO

Malignant melanoma remains a challenge for clinical practice and novel therapeutic strategies are urgently needed. Herbacetin, a natural flavonoid compound that has multiple pharmacological activities, exerts anticancer effects on several human tumors. In this study, the anti-angiogenesis effect of Herbacetin in human malignant melanoma was investigated. The results indicated that Herbacetin treatment significantly suppressed tumor growth and angiogenesis of malignant melanoma both in vitro and in vivo. In melanoma A375 and Hs294T cells, Herbacetin treatment suppressed both EGF-induced and constitutive phosphorylation of EGFR, accelerated the internalization and degradation of EGFR, and subsequently suppressed the activation of the downstream kinases (AKT and ERK). Moreover, MMP9 was determined as a key angiogenic factor in Herbacetin treated melanoma cells. Knockdown of MMP9 suppressed the in vitro angiogenesis while overexpression of MMP9 in Herbacetin treated melanoma cells restored the angiogenesis ability. We concluded that Herbacetin suppressed melanoma angiogenesis through blocking EGFR-ERK/AKT-MMP9 signaling pathway and Herbacetin may be developed as a potential drug for melanoma treatment.


Assuntos
Flavonoides/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Metaloproteinase 9 da Matriz/metabolismo , Melanoma/irrigação sanguínea , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/irrigação sanguínea , Neoplasias Cutâneas/tratamento farmacológico , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Flavonoides/uso terapêutico , Humanos , Camundongos , Camundongos Nus , Neovascularização Patológica/tratamento farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Melanoma Maligno Cutâneo
13.
Ultrason Sonochem ; 53: 178-186, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30642802

RESUMO

Microbubble-mediated sonoporation is a promising strategy for intracellular gene/drug delivery, but the biophysical mechanisms involved in the interactions between microbubbles and cells are not well understood. Here, HeLa cells were synchronized in individual cycle phases, then the cell-cycle-dependences of the membrane permeability and viability of HeLa cells undergoing multi-bubble sonoporation were evaluated using focused ultrasound exposure apparatus coupled passive cavitation detection system. The results indicated that: (1) the microbubble cavitation activity should be independent on cell cycle phases; (2) G1-phase cells with the largest Young's modulus were the most robust against microbubble-mediated sonoporation; (3) G2/M-phase cells exhibited the greatest accumulated FITC uptake with the lowest viability, which should be mainly attributed to the chemical effect of synchronization drugs; and (4) more important, S-phase cells with the lowest stiffness seemed to be the most susceptible to the mechanical effect generated by microbubble cavitation activity, which resulted in the greatest enhancement in sonoporation-facilitated membrane permeabilization without further scarifying their viability. The current findings may benefit ongoing efforts aiming to pursue rational utilization of microbubble-mediated sonoporation in cell-cycle-targeted gene/drug delivery for cancer therapy.


Assuntos
Ciclo Celular , Permeabilidade da Membrana Celular , Microbolhas , Ondas Ultrassônicas , Fenômenos Biomecânicos , Sobrevivência Celular , Fluoresceína-5-Isotiocianato/metabolismo , Células HeLa , Humanos
14.
Proc Natl Acad Sci U S A ; 115(6): 1388-1393, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29363594

RESUMO

RNA interference (RNAi) in plants can move from cell to cell, allowing for systemic spread of an antiviral immune response. How this cell-to-cell spread of silencing is regulated is currently unknown. Here, we describe that the C4 protein from Tomato yellow leaf curl virus can inhibit the intercellular spread of RNAi. Using this viral protein as a probe, we have identified the receptor-like kinase (RLK) BARELY ANY MERISTEM 1 (BAM1) as a positive regulator of the cell-to-cell movement of RNAi, and determined that BAM1 and its closest homolog, BAM2, play a redundant role in this process. C4 interacts with the intracellular domain of BAM1 and BAM2 at the plasma membrane and plasmodesmata, the cytoplasmic connections between plant cells, interfering with the function of these RLKs in the cell-to-cell spread of RNAi. Our results identify BAM1 as an element required for the cell-to-cell spread of RNAi and highlight that signaling components have been coopted to play multiple functions in plants.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Proteínas Serina-Treonina Quinases/metabolismo , Interferência de RNA , Proteínas Virais/genética , Arabidopsis/virologia , Proteínas de Arabidopsis/genética , Begomovirus/química , Interações Hospedeiro-Patógeno/genética , Células Vegetais , Plantas Geneticamente Modificadas , Proteínas Serina-Treonina Quinases/genética , Nicotiana/genética , Proteínas Virais/metabolismo
15.
Theranostics ; 7(19): 4894-4908, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29187912

RESUMO

Microbubble-mediated sonoporation has shown its great potential in facilitating intracellular uptake of gene/drugs and other therapeutic agents that are otherwise difficult to enter cells. However, the biophysical mechanisms underlying microbubble-cell interactions remain unclear. Particularly, it is still a major challenge to get a comprehensive understanding of the impact of cell cycle phase on the cellular responses simultaneously occurring in cell membrane and cytoskeleton induced by microbubble sonoporation. Methods: Here, efficient synchronizations were performed to arrest human cervical epithelial carcinoma (HeLa) cells in individual cycle phases. The, topography and stiffness of synchronized cells were examined using atomic force microscopy. The variations in cell membrane permeabilization and cytoskeleton arrangement induced by sonoporation were analyzed simultaneously by a real-time fluorescence imaging system. Results: The results showed that G1-phase cells typically had the largest height and elastic modulus, while S-phase cells were generally the flattest and softest ones. Consequently, the S-Phase was found to be the preferred cycle for instantaneous sonoporation treatment, due to the greatest enhancement of membrane permeability and the fastest cytoskeleton disassembly at the early stage after sonoporation. Conclusion: The current findings may benefit ongoing efforts aiming to pursue rational utilization of microbubble-mediated sonoporation in cell cycle-targeted gene/drug delivery for cancer therapy.


Assuntos
Ciclo Celular/efeitos da radiação , Membrana Celular/efeitos da radiação , Ondas Ultrassônicas , Membrana Celular/metabolismo , Permeabilidade da Membrana Celular/efeitos da radiação , Citoesqueleto/metabolismo , Citoesqueleto/efeitos da radiação , Células HeLa , Humanos , Microbolhas , Ultrassom/instrumentação , Ultrassom/métodos
16.
Primates ; 55(2): 239-47, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24220849

RESUMO

Generally, food abundance and distribution exert important influence on primate ranging behavior. Hoolock gibbons (genus Hoolock) live in lowland and montane forests in India, Bangladesh, Myanmar and China. All information about hoolock gibbons comes from studies on western hoolock gibbons (Hoolock hoolock) living in lowland forest. Between August 2010 and September 2011, we studied the ranging behavior of one habituated group of eastern hoolock gibbon (H. leuconedys) living in a seasonal montane forest in Gaoligongshan, Yunnan, China. Results show that the study group did not increase foraging effort, calculated in this study as the daily path length, when fruit was less available. Instead, the gibbons fed more on leaves and decreased traveling to conserve energy. They relied heavily on a single food species in most study months which was patchily distributed within their total (14-month) home range, and during most months they used only a small portion of their total home range. In order to find enough food, the group shifted its monthly home range according to the seasonal availability of food species. To satisfy their annual food requirements, they occupied a total home range of 93 ha. The absence of neighboring groups of gibbons and the presence of tsaoko cardamom (Amomum tsaoko) plantations may also have influenced the ranging behavior of the group. Further long-term studies of neighboring groups living in intact forests are required to assess these effects.


Assuntos
Comportamento Animal/fisiologia , Florestas , Hylobates/fisiologia , Atividade Motora , Animais , China , Dieta/veterinária , Territorialidade
17.
Primates ; 54(2): 137-46, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23192193

RESUMO

Most gibbons dwell in the tropical forests of Southeastern Asia, but eastern hoolock gibbons (Hoolock leuconedys) survive in high montane forest ranging from 1,600 to 2,700 m a.s.l. in Gaoligongshan (>24°30'N), Yunnan, China. To assess the behavioral adaptations of hoolock gibbons to the montane forest, we related temperature and food availability within the habitat to the seasonal behavioral patterns of a family group and a solitary female between August 2010 and September 2011 in Nankang, Gaoligongshan National Nature Reserve. The maximum temperature was 29.2 °C and the minimum temperature was -0.3 °C during the period. The monthly mean temperature was <10 °C between December and February, making Nankang the coldest gibbon habitat reported so far. Nonfig fruit and fig availability declined to nearly zero in cold months. The family group increased resting and decreased travel and social behaviors when the monthly mean temperature was low. Compared with other gibbon populations, the hoolock gibbons spent proportionally less time feeding on figs and other fruit than other gibbon populations except Nomascus concolor and Symphalangus syndactylus. Only 36 species of plants provided nonfig fruit or figs, which is less than the number of fruit species consumed by any other gibbon population observed during a similar period of time (about 1 year). Hoolock gibbons shifted their diet to leaves and increased feeding time when fruit was not available. We conclude that diet flexibility and an energy-conserving strategy during the cold season when fruit is scarce have enabled the hoolock gibbons to survive in a northern montane forest.


Assuntos
Dieta , Ecossistema , Comportamento Alimentar , Hylobatidae/fisiologia , Atividade Motora , Adaptação Fisiológica , Animais , China , Feminino , Frutas/crescimento & desenvolvimento , Comportamento de Retorno ao Território Vital , Masculino , Temperatura
18.
Folia Primatol (Basel) ; 81(1): 1-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20134169

RESUMO

We studied the altitudinal ranging of one habituated group of black-crested gibbons (Nomascus concolor) at Dazhaizi, Mt. Wuliang, Yunnan, China, between March 2005 and April 2006. The group ranged from 1,900 to 2,680 m above sea level. Food distribution was the driving force behind the altitudinal ranging patterns of the study group. They spent 83.2% of their time ranging between 2,100 and 2,400 m, where 75.8% of important food patches occurred. They avoided using the area above 2,500 m despite a lack of human disturbance there, apparently because there were few food resources. Temperature had a limited effect on seasonal altitudinal ranging but probably explained the diel altitudinal ranging of the group, which tended to use the lower zone in the cold morning and the higher zone in the warm afternoon. Grazing goats, the main disturbance, were limited to below 2,100 m, which was defined as the high-disturbance area (HDA). Gibbons spent less time in the HDA and, when ranging there, spent more time feeding and travelling and less time resting and singing. Human activities directly influenced gibbon behaviour, might cause forest degradation and create dispersal barriers between populations.


Assuntos
Comportamento Alimentar , Hylobates/fisiologia , Atividade Motora , Altitude , Animais , China , Ritmo Circadiano , Demografia , Ecossistema , Atividades Humanas , Estações do Ano , Temperatura
19.
Am J Primatol ; 70(9): 871-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18548511

RESUMO

We studied the ranging behavior of a habituated group of black crested gibbons (Nomascus concolor jingdongensis) in a high, seasonal habitat on Mt. Wuliang, central Yunnan, China, between March 2005 and April 2006. Our results indicated that the total home range size for the study group was 129 ha, or 151 ha if the lacunae within the borders in which gibbons were not observed were included. This is a much bigger range size than that of other gibbon species. However, 69.7% of their activities occurred within 29 ha. The intensity of quadrant use was significantly correlated with the distribution of important food patches. The mean yearly daily path length was 1,391 m. Gibbons traveled farther when they spent more time feeding on fruit. To avoid often passing through ridges with little food, gibbons usually stayed in the same valley for successive days, and then moved on to another valley for another several days, which resulted in a concentrated ranging pattern.


Assuntos
Comportamento Animal/fisiologia , Ecossistema , Comportamento Alimentar/fisiologia , Hylobates/fisiologia , Atividade Motora/fisiologia , Animais , China , Alimentos , Chuva , Temperatura , Fatores de Tempo
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