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1.
J Nanobiotechnology ; 22(1): 487, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39143493

RESUMO

Mitochondria are crucial organelles responsible for energy generation in eukaryotic cells. Oxidative stress, calcium disorders, and mitochondrial DNA abnormalities can all cause mitochondrial dysfunction. It is now well documented that mitochondrial dysfunction significantly contributes to the pathogenesis of numerous illnesses. Hence, it is vital to investigate innovative treatment methods targeting mitochondrial dysfunction. Extracellular vesicles (EVs) are cell-derived nanovesicles that serve as intercellular messengers and are classified into small EVs (sEVs, < 200 nm) and large EVs (lEVs, > 200 nm) based on their sizes. It is worth noting that certain subtypes of EVs are rich in mitochondrial components (even structurally intact mitochondria) and possess the ability to transfer them or other contents including proteins and nucleic acids to recipient cells to modulate their mitochondrial function. Specifically, EVs can modulate target cell mitochondrial homeostasis as well as mitochondria-controlled apoptosis and ROS generation by delivering relevant substances. In addition, the artificial modification of EVs as delivery carriers for therapeutic goods targeting mitochondria is also a current research hotspot. In this article, we will focus on the ability of EVs to modulate the mitochondrial function of target cells, aiming to offer novel perspectives on therapeutic approaches for diverse conditions linked to mitochondrial dysfunction.


Assuntos
Vesículas Extracelulares , Mitocôndrias , Vesículas Extracelulares/metabolismo , Humanos , Mitocôndrias/metabolismo , Animais , Espécies Reativas de Oxigênio/metabolismo , Estresse Oxidativo , Apoptose , Doenças Mitocondriais/metabolismo , Doenças Mitocondriais/terapia , Sistemas de Liberação de Medicamentos/métodos
2.
J Antimicrob Chemother ; 78(7): 1795-1799, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37279764

RESUMO

OBJECTIVES: The 'treat-all' strategy was implemented in Shenzhen, China in 2016. The effect of this extensive treatment on transmitted drug resistance (TDR) of HIV is unclear. METHODS: TDR analysis was performed, based on the partial HIV-1 pol gene obtained from the newly reported HIV-1 positive cases from 2011 to 2019 in Shenzhen, China. The HIV-1 molecular transmission networks were inferred to analyse the spread of TDR. Logistic regression was used to identify the potential risk factors with TDR mutations (TDRMs) to cluster. RESULTS: A total of 12 320 partial pol sequences were included in this study. The prevalence of TDR was 2.95% (363/12 320), which increased from 2.57% to 3.52% after 'treat-all'. The TDR prevalence was increased in populations with the characteristics of CRF07_BC, being single, educated to junior college level and above, MSM and male. The sensitivities of viruses to six antiretroviral drugs were decreased. The clustering rate of TDRMs remained stable, and the sequences in the three drug resistance transmission clusters (DRTCs) were mainly found during 2011-16. CRF07_BC and CRF55_01B were the factors associated with TDRMs clustering in the networks. CONCLUSIONS: The 'treat-all' strategy might have contributed to a small increase in TDR, while most of the TDRMs were distributed sporadically, which implies that the 'treat-all' strategy is helpful for the control of TDR in high-risk populations.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Minorias Sexuais e de Gênero , Humanos , Masculino , Homossexualidade Masculina , HIV-1/genética , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Prevalência , Farmacorresistência Viral/genética , China/epidemiologia , Filogenia , Genótipo
3.
Environ Res ; 231(Pt 3): 116248, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37245575

RESUMO

Data center is a very important infrastructure to support the development of information technology, and its development and increment are very remarkable. However, with the rapid and large-scale development of data centers, the problem of energy consumption turns to be also very prominent. Under the background of global carbon peak and carbon neutrality, developing green and low-carbon data centers has become an inevitable trend. This paper reviews and analyzes the policies and their roles in promoting China's green development of data centers in the past 10 years, summarizes the current situation of the implementation of green data center projects in China and gives the changes of PUE limits of data centers under the policy constraints. Application of green technologies is an important measure for energy-saving and low-carbon development of data centers, so encouraging innovation and application of green technologies in data center is also a priority task in relevant policies. This paper points out the green and low-carbon technology system of data centers, further summarizes energy-saving and carbon-reducing technologies in IT equipment, cooling system, power supply and distribution system, lighting, intelligent operation and maintenance, and provides an outlook on the future green development of data centers.


Assuntos
Carbono , Tecnologia , China , Fontes de Energia Elétrica , Políticas , Desenvolvimento Econômico
4.
J Nanobiotechnology ; 20(1): 353, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35918718

RESUMO

Human umbilical cord mesenchymal stem cells-derived small extracellular vesicles (hucMSC-sEVs) have been demonstrated as a therapeutic agent to prevent and treat cisplatin-induced acute kidney injury (AKI). However, hucMSC-sEVs still face many problems and challenges in the repair and treatment of tissue injury, including short circulation time, insufficient targeting, and low therapeutic efficacy. Therefore, we constructed engineered hybrid vesicles fused with nanovesicles derived from human neutrophil membranes and hucMSC-sEVs, named neutrophil membrane engineered hucMSC-sEVs (NEX). NEX significantly enhanced the targeting of hucMSC-sEVs to injured kidney tissues, improved the impaired renal function via reducing pro-inflammatory cytokines expression, promoted the proliferation of renal tissue cells, and inhibited renal cell apoptosis in vivo. In addition, NEX enhanced hucMSC-sEVs uptake by NRK52E cells, but inhibited its uptake by RAW264.7 cells. Moreover, administration of NEX reduced cellular oxidative stress and promoted proliferation of NRK52E cells treated with cisplatin in vitro. In summary, our findings indicate that this design of a universal approach enhances the targeting and therapeutic efficacy of hucMSC-sEVs in kidney tissue regeneration, and provides new evidence promoting its clinical application.


Assuntos
Injúria Renal Aguda , Exossomos , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/terapia , Cisplatino , Exossomos/metabolismo , Humanos , Neutrófilos , Cordão Umbilical/metabolismo
5.
Angew Chem Int Ed Engl ; 61(32): e202206108, 2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35670014

RESUMO

Charge transfer between metal sites and supports is crucial for catalysis. Redox-inert supports are usually unfavorable due to their less electronic interaction with metal sites, which, we demonstrate, is not always correct. Herein, three metal-organic frameworks (MOFs) are chosen to mimic inert or active supports for Pt nanoparticles (NPs) and the photocatalysis is studied. Results demonstrate the formation of a Schottky junction between Pt and the MOFs, leading to the electron-donation effect of the MOFs. Under light irradiation, both the MOF electron-donation effect and Pt interband excitation dominate the Pt electron density. Compared with the "active" UiO-66 and MIL-125 supports, Pt NPs on the "inert" ZIF-8 exhibit higher electron density due to the higher Schottky barrier, resulting in superior photocatalytic activity. This work optimizes metal catalysts with non-reducible supports, and promotes the understanding of the relationship between the metal-support interaction and photocatalysis.

6.
Angew Chem Int Ed Engl ; 61(47): e202211216, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36165270

RESUMO

The exposed facets of supported catalysts play a crucial role in catalysis; however, they are usually ignored and related studies remain rare. Herein, we have fabricated a series of sandwich-structured metal-organic framework composites, denoted ZIF-8X @Pd@ZIF-8 (x represents the morphology of ZIF-8 core, i.e., ZIF-8C exposing (100) facet, ZIF-8RD exposing (110) facet, and ZIF-8TRD exposing mixed (100) and (110) facets), featuring Pd nanoparticles deposited on the specific crystal facets of ZIF-8 core, for hydrogenation of p-chloronitrobenzene. The Pd electronic state is tailored by the ZIF-8 core, where more electron-deficient Pd is found in ZIF-8C @Pd@ZIF-8 than that in ZIF-8RD @Pd@ZIF-8, leading to discriminative adsorption of the -NO2 and -Cl groups of p-chloronitrobenzene. Consequently, ZIF-8C @Pd@ZIF-8 exhibits excellent activity (97.6 %) and selectivity (98.1 %) to p-chloroaniline. This work highlights crystal facet engineering of supports to modulate the microenvironment and electronic state of supported metal nanoparticles, offering a promising avenue to enhanced catalysis.

7.
Mol Carcinog ; 57(9): 1223-1236, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29749061

RESUMO

Exosomes are critically involved in tumor growth, metastasis, and therapy resistance. Exosomes have the potential to be utilized as cancer biomarkers. In this study, we aimed to explore the roles and clinical values of exosomal miRNAs in gastric cancer. We found that the concentration of exosomes was significantly higher in the serum of gastric cancer patients and the culture supernatants of gastric cancer cells than that in healthy volunteers and gastric mucosa epithelial cells. In particular, miR-423-5p was elevated in the serum exosomes of gastric cancer patients, and the level of exosomal miR-423-5p was remarkably correlated with lymph node metastasis. High level of exosomal miR-423-5p was associated with poor outcome in gastric cancer patients. MiR-423-5p enriched exosomes could be internalized into gastric cancer cells, which enhanced cell proliferation and migration both in vitro and in vivo. Mechanistically, miR-423-5p inhibited the expression of suppressor of fused protein (SUFU) to enhance the proliferation and migration of gastric cancer cells. The expression levels of SUFU were significantly decreased in gastric cancer cells and the tumor tissues of gastric cancer patients. Taken together, our findings indicate that exosomes could deliver miR-423-5p to promote cancer growth and metastasis and serum exosomal miR-423-5p may serve as a potential marker for gastric cancer diagnosis and prognosis.


Assuntos
Exossomos/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Proteínas Repressoras/genética , Neoplasias Gástricas/genética , Animais , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Proliferação de Células , Exossomos/patologia , Feminino , Humanos , Linfonodos/patologia , Masculino , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Metástase Neoplásica/genética , Metástase Neoplásica/patologia , Prognóstico , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patologia
8.
Virus Genes ; 52(6): 887-890, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27519364

RESUMO

Bocaviruses have been found in the feces of humans and a variety of animals, including pigs, cattle, dogs, gorillas, cats, and sea lions. Here, we have characterized the almost complete genome (5224 nt) of a novel bocavirus from feces of domestic minks, which has been provisionally named mink bocavirus. The NS1 protein of mink bocavirus shared 36.9-52 % amino acid sequence identities with those of other known bocaviruses and phylogenetically clustered with bocaviruses from other carnivores. According to the genetic distance-based criteria, mink bocavirus qualifies as a novel species of bocavirus. PCR of feces from a group of domestic minks, which included both healthy animals and animals suffering from diarrhea, revealed that 30 % (9/30) shed virus. However, no association between viral shedding and the presence of diarrhea could be determined.


Assuntos
Animais Domésticos , Bocavirus/classificação , Bocavirus/genética , Vison/virologia , Sequência de Aminoácidos , Animais , China , DNA Viral , Ordem dos Genes , Genoma Viral , Fases de Leitura Aberta , Filogenia , Análise de Sequência de DNA
9.
Virus Genes ; 52(1): 130-3, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26604002

RESUMO

Bufavirus (BuV) was first discovered from feces of children with acute diarrhea. It was subsequently detected from several animal species including shrews, bats, and nonhuman primates. In this study, we identified a novel Protoparvovirus, designated RatBuV, from the intestinal contents of wild rats using viral metagenomics. The near complete genome was 4643 nt encoding NS1, VP1, and VP2 proteins. Phylogenetic analysis over the complete genome showed that RatBuV clustered with Mpulungu BuV from shrews. Sequence analysis indicated that the putative protein sequences of NS1, VP1, and VP2 of RatBuV shared identities of 50.6-77.2, 48.3-77.3, and 47.1-78.3 %, respectively, with those of human BuVs, MpBuV, and WUHARV parvovirus, suggesting RatBuV belongs to a new species of Protoparvovirus. Our epidemiologic study indicated that the prevalence rate of RatBuV in the cohort of 40 wild rats is 12.5 % (5/40), which is higher than that of BuV in humans in a previous study.


Assuntos
Parvovirinae/isolamento & purificação , Ratos/virologia , Sequência de Aminoácidos , Animais , Animais Selvagens/virologia , China , Fezes/virologia , Genoma Viral , Intestinos/virologia , Dados de Sequência Molecular , Infecções por Parvoviridae/virologia , Parvovirinae/classificação , Parvovirinae/genética , Filogenia , Alinhamento de Sequência , Proteínas Virais/química , Proteínas Virais/genética
10.
BMC Cancer ; 15: 793, 2015 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-26498753

RESUMO

BACKGROUND: Emerging evidence indicates that inappropriate cell-cell fusion might contribute to cancer progression. Similarly, mesenchymal stem cells (MSCs) can also fuse with other cells spontaneously and capable of adopting the phenotype of other cells. The aim of our study was to investigate the role of MSCs participated cell fusion in the tumorigenesis of gastric cancer. METHODS: We fused human umbilical cord mesenchymal stem cells (hucMSCs) with gastric cancer cells in vitro by polyethylene glycol (PEG), the hybrid cells were sorted by flow cytometer. The growth and migration of hybrids were assessed by cell counting, cell colony formation and transwell assays. The proteins and genes related to epithelial- mesenchymal transition and stemness were tested by western blot, immunocytochemistry and real-time RT-PCR. The expression of CD44 and CD133 was examined by immunocytochemistry and flow cytometry. The xenograft assay was used to evaluation the tumorigenesis of the hybrids. RESULTS: The obtained hybrids exhibited epithelial- mesenchymal transition (EMT) change with down-regulation of E-cadherin and up-regulation of Vimentin, N-cadherin, α-smooth muscle actin (α-SMA), and fibroblast activation protein (FAP). The hybrids also increased expression of stemness factors Oct4, Nanog, Sox2 and Lin28. The expression of CD44 and CD133 on hybrid cells was stronger than parental gastric cancer cells. Moreover, the migration and proliferation of heterotypic hybrids were enhanced. In addition, the heterotypic hybrids promoted the growth abilities of gastric xenograft tumor in vivo. CONCLUSIONS: Taken together, our results suggest that cell fusion between hucMSCs and gastric cancer cells could contribute to tumorigenic hybrids with EMT and stem cell-like properties, which may provide a flexible tool for investigating the roles of MSCs in gastric cancer.


Assuntos
Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Transformação Celular Neoplásica/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Neoplásicas/metabolismo , Neoplasias Gástricas/metabolismo , Animais , Carcinogênese/metabolismo , Carcinogênese/patologia , Linhagem Celular Tumoral , Transformação Celular Neoplásica/patologia , Humanos , Células-Tronco Mesenquimais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células-Tronco Neoplásicas/patologia , Neoplasias Gástricas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
11.
Micromachines (Basel) ; 15(1)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38258246

RESUMO

With the technological scaling of metal-oxide-semiconductor field-effect transistors (MOSFETs) and the scarcity of circuit design margins, the characteristics of device reliability have garnered widespread attention. Traditional single-mode reliability mechanisms and modeling are less sufficient to meet the demands of resilient circuit designs. Mixed-mode reliability mechanisms and modeling have become a focal point of future designs for reliability. This paper reviews the mechanisms and compact aging models of mixed-mode reliability. The mechanism and modeling method of mixed-mode reliability are discussed, including hot carrier degradation (HCD) with self-heating effect, mixed-mode aging of HCD and Bias Temperature Instability (BTI), off-state degradation (OSD), on-state time-dependent dielectric breakdown (TDDB), and metal electromigration (EM). The impact of alternating HCD-BTI stress conditions is also discussed. The results indicate that single-mode reliability analysis is insufficient for predicting the lifetime of advanced technology and circuits and provides guidance for future mixed-mode reliability analysis and modeling.

12.
Nat Commun ; 15(1): 5855, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38997298

RESUMO

Plasmonic materials can generate strong electromagnetic fields to boost the Raman scattering of surrounding molecules, known as surface-enhanced Raman scattering. However, these electromagnetic fields are heterogeneous, with only molecules located at the 'hotspots', which account for ≈ 1% of the surface area, experiencing efficient enhancement. Herein, we propose patterned plasmonic trimers, consisting of a pair of plasmonic dimers at the bilateral sides and a trap particle positioned in between, to address this challenge. The trimer configuration selectively directs probe molecules to the central traps where 'hotspots' are located through chemical affinity, ensuring a precise spatial overlap between the probes and the location of maximum field enhancement. We investigate the Raman enhancement of the Au@Al2O3-Au-Au@Al2O3 trimers, achieving a detection limit of 10-14 M of 4-methylbenzenethiol, 4-mercaptopyridine, and 4-aminothiophenol. Moreover, single-molecule SERS sensitivity is demonstrated by a bi-analyte method. Benefiting from this sensitivity, our approach is employed for the early detection of lung tumors using fresh tissues. Our findings suggest that this approach is sensitive to adenocarcinoma but not to squamous carcinoma or benign cases, offering insights into the differentiation between lung tumor subtypes.


Assuntos
Ouro , Neoplasias Pulmonares , Nanopartículas Metálicas , Análise Espectral Raman , Análise Espectral Raman/métodos , Neoplasias Pulmonares/diagnóstico , Ouro/química , Humanos , Nanopartículas Metálicas/química , Compostos de Sulfidrila/química , Compostos de Anilina/química , Adenocarcinoma/diagnóstico , Limite de Detecção , Piridinas/química
13.
ACS Nano ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016025

RESUMO

The exploitation of hierarchical carbon nanocages with superior light-to-heat conversion efficiency, together with their distinct structural, morphological, and electronic properties, in photothermal applications could provide effective solutions to long-standing challenges in diverse areas. Here, we demonstrate the discovery of pristine and nitrogen-doped hierarchical carbon nanocages as superior supports for highly loaded, small-sized Ru particles toward enhanced photothermal CO2 catalysis. A record CO production rate of 3.1 mol·gRu-1·h-1 with above 90% selectivity in flow reactors was reached for hierarchical nitrogen-doped carbon-nanocage-supported Ru clusters under 2.4 W·cm-2 illumination without external heating. Detailed studies reveal that the enhanced performance originates from the strong broadband sunlight absorption and efficient light-to-heat conversion of nanocage supports as well as the excellent intrinsic catalytic reactivity of sub-2 nm Ru particles. Our study reveals the great potential of hierarchical carbon nanocages in photothermal catalysis to reduce the fossil fuel consumption of various industrial chemical processes and stimulates interest in their exploitation for other demanding photothermal applications.

14.
Artigo em Inglês | MEDLINE | ID: mdl-38517080

RESUMO

With the prevalence of human immunodeficiency virus type 1 (HIV-1) CRF01_AE and CRF07_BC subtypes in China, the co-circulation of multiple subtypes in the HIV-1-positive population may result in dual infection or superinfection in the population, leading to the emergence of unique recombinant forms (URFs) of the HIV-1 virus. In this study, two second-generation unique recombinant strains, BI0114 and BI0116, were identified, and their near full-length genome sequences were obtained. Recombination analysis showed that both sequences were isoforms of URF_0107, and they were second-generation unique recombinant strains formed by the recombination of CRF01_AE and CRF07_BC, with the isoforms being CRF01_AE and CRF0107_BC, respectively. The continued emergence of novel CRF01_AE/CRF07_BC recombinant strains suggests that the epidemiological, preventive, and control situation of HIV-1 is complex and that the relevant health authorities urgently need to establish responses to the challenges posed by changes in the pattern of strain recombination.

15.
Nanomaterials (Basel) ; 13(9)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37177052

RESUMO

A coupling mechanism between flicker noise and hot carrier degradation (HCD) is revealed in this work. Predicting the flicker noise properties of fresh and aged devices is becoming essential for circuit designs, requiring an understanding of the fundamental noise behaviors. While certain models for fresh devices have been proposed, those for aged devices have not been reported yet because of the lack of a clear mechanism. The flicker noise of aged FinFETs is characterized based on the measure-stress-measure (MSM) method and analyzed from the device physics. It is found that both the mean and deviations of the noise power spectral density increase compared with the fresh counterparts. A coupling mechanism is proposed to explain the trap time constants, leading to the trap characterizations in their energy profiles. The amplitude and number of contributing traps are also changing and are dependent on the mode of HCD and determined by the position of the induced traps. A microscopic picture is developed from the perspective of trap coupling, reproducing well the measured noise of advanced nanoscale FinFETs. The finding is important for accurate flicker noise calculations and aging-aware circuit designs.

16.
Arch Insect Biochem Physiol ; 80(1): 1-14, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22128070

RESUMO

Apolipophorin III (apoLp-III) functions in lipid transport and immune activation in insects. We cloned a cDNA encoding putative apoLp-III from larvae of Thitarodes pui, a host species of Ophiocordyceps sinensis, with great economic importance in the Tibetan Plateau. Excluding a putative signal peptide of the first 20 amino acid residues, the 171-residue mature apoLp-III has a calculated molecular mass of 18,606 Da. T. pui apoLp-III shares little sequence homologies (<36%) with other apoLp-IIIs. Phylogenetic analysis reveals that T. pui apoLp-III belongs to a distinct, early diverging lineage of lepidopteran apoLp-IIIs. Homology modeling of T. pui apoLp-III shows a bundle of five amphipathic α-helices, including a short helix 3'. T. pui apoLp-III was constitutively expressed in larval fat body at lower levels than pupal and adult fat body. Significant induction of apoLp-III expression, associated with strongest nodulation response, was observed in both sixth and eighth instar larvae challenged with Beauveria bassiana conidia at 1 hr after inoculation, compared with saline-injected controls. The inoculation experiment as well as previous field studies revealed the relative susceptibility of the sixth instar to the entomopathogenic fungus. ApoLp-III transcripts in the infected sixth and eighth instars were found to be induced highest 2- and 14.7-fold, respectively, during the first 12 hr. In late-stage infection, the infected susceptible sixth instar showed decrease in apoLp-III expression followed by production of B. bassiana hyphal bodies, whereas the infected eighth instar showed longer lasting increase in the expression. These results suggest that apoLp-III might contribute to T. pui immune response against fungal pathogens.


Assuntos
Apolipoproteínas/fisiologia , Proteínas de Insetos/fisiologia , Mariposas/fisiologia , Sequência de Aminoácidos , Animais , Apolipoproteínas/química , Apolipoproteínas/genética , Sequência de Bases , Beauveria/imunologia , Proteínas de Insetos/química , Proteínas de Insetos/genética , Larva/imunologia , Larva/metabolismo , Masculino , Dados de Sequência Molecular , Mariposas/química , Mariposas/genética , Filogenia , Análise de Sequência de DNA , Homologia Estrutural de Proteína
17.
J Invertebr Pathol ; 111(2): 160-5, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22884674

RESUMO

Thitarodes pui, one of the host species of entomopathogenic fungus Ophiocordyceps sinensis, has great economic importance in the Tibetan Plateau. We report here, for the first time, a gregarine parasite found in the coelom of 7th instar and adults of T. pui. Gregarine gamonts (ovoid, ~15×8 µm) underwent syzygy to produce reproductive gametocysts in T. pui larval hemolymph. All infected T. pui carried 2-17 mature gametocysts filled with numerous oocysts (lemon-shaped, 17.17±0.73×6.49±0.4 µm). Transmission electron microscopy showed that these oocysts contained vacuoles of various sizes and amylopectin granules in the cytoplasm; scanning electron microscopy revealed a number of small bumps all over the surface of these oocysts. Small subunit ribosomal DNA sequence analysis showed a close relationship between the gregarine and the species of Ascogregarina (Eugregarinorida: Lecudinidae). Internal transcribed spacers and 5.8S ribosomal DNA from this gregarine exhibited 76% highest sequence identity with that from Ascogregarina culicis Ross.


Assuntos
Apicomplexa/fisiologia , Mariposas/parasitologia , Animais , Apicomplexa/genética , Apicomplexa/ultraestrutura , Sequência de Bases , DNA de Protozoário/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Filogenia , Alinhamento de Sequência , Tibet
18.
Oxid Med Cell Longev ; 2022: 6742792, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35979398

RESUMO

Aging shows a decline in overall physical function, and cellular senescence is the powerful catalyst leading to aging. Considering that aging will be accompanied with the emergence of various aging-related diseases, research on new antiaging drugs is still valuable. Extracellular vesicles (EVs), as tools for intercellular communication, are important components of the senescence-associated secretory phenotype (SASP), and they can play pathological roles in the process of cellular senescence. In addition, EVs are similar to their original cells in functions. Therefore, EVs derived from pathological tissues or body fluids may be closely related to the progression of diseases and become potential biomarkers, while those from healthy cells may have therapeutic effects. Moreover, EVs are satisfactory drug carriers. At present, numerous studies have supported the idea that engineered EVs could improve drug targeting ability and utilization efficiency. Here, we summarize the characteristics of EVs and cellular senescence and focus on the diagnostic and therapeutic potential of EVs in various aging-related diseases, including Alzheimer disease, osteoporosis, cardiovascular disease, diabetes mellitus and its complications, and skin aging.


Assuntos
Vesículas Extracelulares , Biomarcadores , Comunicação Celular , Senescência Celular
19.
Biochem Mol Biol Educ ; 50(1): 114-119, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34854213

RESUMO

In order to cultivate the ability of independent learning and lifelong learning of medical students, improve the ability of students to analyze and solve problems, improve the competence of medical talents and cultivate high-level and innovative talents, we have constructed the blended teaching model of "Clinical Case Investigation-Online Open Course Learning-Classroom PBL Seminar-After-Class Health Education". At the same time, an ability-oriented performance evaluation system improved the teaching quality feedback system has also established. This article introduces the construction and application of the blended teaching model, as well as the problems it faces, provides a theoretical basis for the optimization and improvement of this model. It also provides a model theory and practical basis for creating a blended online and offline "golden course" for the professional courses of medical laboratory technology.


Assuntos
Educação a Distância , Estudantes de Medicina , China , Humanos , Aprendizagem , Ensino
20.
Stem Cells Int ; 2022: 9668239, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35087591

RESUMO

Mesenchymal stem cell- (MSC-) derived extracellular vesicles (EVs) serving as delivery system have attracted extensive research interest, especially in cancer therapy. In our previous study, lipocalin-type prostaglandin D2 synthase (L-PGDS) showed inhibitory effects on gastric cancer growth. In this study, we aimed to explore whether MSC-EV-delivered L-PGDS (EVs-L-PGDS) could inhibit gastric cancer progression. EVs-L-PGDS were generated from MSCs transfected with adenovirus encoding L-PGDS. Cell colony-forming, migration, invasion, and flow cytometry assays were used to show the inhibitory effects of EVs on tumor cells in vitro, and the nude mouse subcutaneous tumor model was performed to show the inhibitory effect of EVs on tumor progression in vivo. In vitro, EVs-L-PGDS could be internalized and inhibit the colony-forming, migration, and invasion ability of gastric cancer cell SGC-7901 and promote cell apoptosis. In vivo, EVs-L-PGDS inhibited the tumor growth in nude mouse subcutaneous tumor-bearing model. Compared with the PBS and EVs containing empty vector (EVs-Vector) group, more apoptotic cells and higher L-PGDS expression were detected in tumor tissue of the EVs-L-PGDS treatment group. And these differences are significant. Mechanistically, EVs-L-PGDS reduced the expression of stem cell markers including Oct4, Nanog, and Sox2 and inhibited STAT3 phosphorylation in gastric cancer cell SGC-7901. In conclusion, our results imply that MSC-derived EVs could be utilized as an effective nanovehicle to deliver L-PGDS for gastric cancer treatment, which provides a novel idea for the EV-based cancer therapy.

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