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1.
Acc Chem Res ; 57(1): 70-92, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38112292

RESUMO

ConspectusThe pursuit of novel and eco-friendly methods in organic synthesis is gaining prominence, with a strong emphasis on green transformations using renewable and sustainable resources. Among these environmentally conscious approaches, water-compatible reactions stand out for their many advantages. Water, as a solvent, offers unmatched abundance, cost-efficiency, and environmental compatibility compared to organic solvents. Its use eliminates the need for complex protection and deprotection steps for reactive functional groups in multistep synthesis and enables the use of water-soluble substrates like proteins and carbohydrates. Water-compatible reactions also provide opportunities to combine with enzymes, resulting in chemoenzymatic transformations that can increase efficiency. Additionally, these reactions facilitate site-specific modification and the bioconjugation of biomolecules, leading to bioconjugate therapeutics.Over nearly three decades, our research group has been dedicated to developing innovative water-compatible methodologies and concepts. This Account provides a comprehensive overview of our contributions since 1994. Our central strategy revolves around integrating green chemistry principles into our methods, focusing on (i) developing reactions that can operate under mild conditions, including room temperature, atmospheric pressure, and physiological pH; (ii) designing atom-economical reactions that minimize waste production; (iii) replacing toxic and flammable organic solvents with eco-friendly alternatives like water and ethanol; and (iv) reducing reliance on metals or halogenated compounds in specific reactions.In this Account, we detail our achievements in developing efficient methodologies in aqueous media, highlighting their scope, limitations, asymmetric control, and applications for synthesizing complex molecules and functionalizing peptides and proteins. Mechanistic investigations underlying these developments are also discussed when applicable. Furthermore, we offer insights into the reasoning behind our work and address future opportunities and challenges in this area of research. We hope that this Account will inspire continued interest and foster new breakthroughs. By exploring innovative and broadly applicable strategies that expand the water-compatible synthetic toolbox, we aim to pave the way for the truly green and sustainable synthesis of complex molecules and pharmaceuticals.

2.
Small ; : e2400587, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38837673

RESUMO

Precise integration of diverse therapeutic approaches into nanomaterials is the key to the development of multimodal synergistic cancer therapy. In this work, tadpole-like carbon nanotubes with Fe nanoparticle encapsulated at the head and Zn single-atom anchored on the body (Fe@CNT-Zn) is precisely designed and facilely prepared via one-pot carbonization. In vitro studies revealed the integration of chemotherapy (CT), chemodynamic therapy (CDT), photothermal therapy (PTT), and photodynamic therapy (PDT) in Fe@CNT-Zn as well as the near-infrared light (NIR)-responsive cascade therapeutic efficacy. Furthermore, in vivo studies demonstrated the NIR-triggered cascade-amplifying synergistic cancer therapy in a B16 tumor-bearing mouse model. The results not only showcased the Fe@CNT-Zn as a potential tetramodal therapeutic platform, but also demonstrated a proof-of-concept on metal-organic framework-based "one stone for multiple birds" strategy for in situ functionalization of carbon materials.

3.
Chem Rev ; 122(24): 17479-17646, 2022 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-36240299

RESUMO

Alkenes and their derivatives are featured widely in a variety of natural products, pharmaceuticals, and advanced materials. Significant efforts have been made toward the development of new and practical methods to access this important class of compounds by selectively activating the alkenyl C(sp2)-H bonds in recent years. In this comprehensive review, we describe the state-of-the-art strategies for the direct functionalization of alkenyl sp2 C-H and C-F bonds until June 2022. Moreover, metal-free, photoredox, and electrochemical strategies are also covered. For clarity, this review has been divided into two parts; the first part focuses on currently available alkenyl sp2 C-H functionalization methods using different alkene derivatives as the starting materials, and the second part describes the alkenyl sp2 C-F bond functionalization using easily accessible gem-difluoroalkenes as the starting material. This review includes the scope, limitations, mechanistic studies, stereoselective control (using directing groups as well as metal-migration strategies), and their applications to complex molecule synthesis where appropriate. Overall, this comprehensive review aims to document the considerable advancements, current status, and emerging work by critically summarizing the contributions of researchers working in this fascinating area and is expected to stimulate novel, innovative, and broadly applicable strategies for alkenyl sp2 C-H and C-F bond functionalizations in the coming years.


Assuntos
Alcenos , Alcenos/química
4.
J Am Chem Soc ; 145(48): 26169-26178, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-37988478

RESUMO

Imaging-guided chemodynamic therapy is widely considered a promising modality for personalized and precision cancer treatment. Combining both imaging and chemodynamic functions in one system conventionally relies on the hybrid materials approach. However, the heterogeneous, ill-defined, and dissociative/disintegrative nature of the composites tends to complicate their action proceedings in biological environments and thus makes the treatment imprecise and ineffective. Herein, a strategy to employ two kinds of inorganic units with different functions─reactive oxygen species generation and characteristic emission─has achieved two single-crystalline metal-organic frameworks (MOFs), demonstrating the competency of reticular chemistry in creating multifunctional materials with atomic precision. The multinary MOFs could not only catalyze the transformation from H2O2 to hydroxyl radicals by utilizing the redox-active Cu-based units but also emit characteristic tissue-penetrating near-infrared luminescence brought by the Yb4 clusters in the scaffolds. Dual functions of MOF nanoparticles are further evidenced by pronounced cell imaging signals, elevated intracellular reactive oxygen species levels, significant cell apoptosis, and reduced cell viabilities when they are taken up by the HeLa cells. In vivo NIR imaging is demonstrated after the MOF nanoparticles are further functionalized. The independent yet interconnected modules in the intact MOFs could operate concurrently at the same cellular site, achieving a high spatiotemporal consistency. Overall, our work suggests a new method to effectively accommodate both imaging and therapy functions in one well-defined material for precise treatment.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Neoplasias , Humanos , Estruturas Metalorgânicas/farmacologia , Estruturas Metalorgânicas/química , Células HeLa , Espécies Reativas de Oxigênio , Peróxido de Hidrogênio , Fototerapia , Nanopartículas/química , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral
5.
Small ; 19(48): e2303063, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37415511

RESUMO

Nanoscale metal-organic frameworks (nanoMOFs) are emerging as an important class of nanomaterials for the systematical investigation of biomedically relevant structure-property relationship (SPR) due to their highly tailorable features. In this work, the reticular chemistry approach is shown to explore the SPR of a fcu-type Zr(IV)-nanoMOF for T1 -weighted magnetic resonance imaging (MRI). Isoreticular replacement of the eight-coordinated square-antiprismatic Zr(IV) by nine-coordinated Gd(III) brings a stoichiometric water capped on the square-antiprismatic site, enabling the relaxation transfer in the inner-sphere, giving the r1 value of 4.55 mM-1 ·s-1 at the doping ratio of Gd : Zr = 1 : 1. Then, these isoreticular engineering studies provide feasible ways to facilitate the relaxation transfer in the second- and outer-sphere of the Gd(III)-doped Zr-oxo cluster for the relaxation respectively. Finally, these in vitro and in vivo MRI studies revealed that the Gd(III)-doped Zr-oxo cluster aggregated underlying the fcu-type framework surpasses its discrete molecular cluster for MRI. These results demonstrated that there is plenty of room inside MOFs for T1 -weighted MRI by reticular chemistry.

6.
Small ; 19(12): e2206503, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36587973

RESUMO

Cancer stem cells (CSCs), a type of cell with self-renewal, unlimited proliferation, and insensitivity to common physical and chemical factors, are the key to cancer metastasis, recurrence, and chemo-resistance. Available CSCs inhibition strategies are mainly based on small molecule drugs, yet are limited by their off-target toxicity. The link between CSCs and non-CSCs interconversion is difficult to sever. In this work, a nanotherapeutic strategy based on MnOx -loaded polydopamine (MnOx /PDA) nanobombs with chemodynamic, photodynamic, photothermal and biodegradation properties to inhibit CSCs and non-CSCs concurrently is reported. The MnOx /PDA nanobombs can directly disrupt the microenvironment and tumorigenic capacity of CSCs by generating hyperthermia, oxidative stress and alleviating hypoxia. The markers of CSCs are subsequently downregulated, leading to the clearance of CSCs. Meanwhile, the synergistic therapy mediated by MnOx /PDA nanobombs can directly ablate the bulk tumor cells, thus cutting off the supply of CSCs transformation. For tumor targeting, MnOx /PDA is coated with macrophage membrane. The final tumor inhibition rate of the synergistic therapy is 70.8% in colorectal cancer (CRC) model. Taken together, the present work may open up the exploration of nanomaterial-based synergistic therapy for the simultaneous elimination of therapeutically resistant CSCs and non-CSCs.


Assuntos
Hipertermia Induzida , Neoplasias , Humanos , Biomimética , Neoplasias/tratamento farmacológico , Fototerapia , Células-Tronco Neoplásicas/patologia , Microambiente Tumoral
7.
Small ; 19(34): e2301894, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37093185

RESUMO

Developing novel synthetic strategies to downsize metal-organic frameworks (MOFs) from polydisperse crystals to monodisperse nanoparticles is of great importance for their potential bioapplications. In this work, a novel synthetic strategy termed gelothermal synthesis is proposed, in which coordination polymer gel is first prepared and followed by a thermal reaction to give the monodisperse MOF nanoparticles. This novel synthetic strategy successfully leads to the isolation of Materials of Institute Lavoisier (MIL-88), Cu(II)-fumarate MOFs (CufumDMF), and Zeolitic Imidazolate Frameworks (ZIF-8) nanoparticles. Focused on MIL-88A, the studies reveal that the size can be well-tuned from nanoscale to microscale without significant changes in polydispersity index (PDI) even in the case of in situ metal substitution. A possible mechanism is consequently proposed based on extensive studies on the gelothermal condition including sol-gel chemistry, thermal condition, kinds of solvents, and so on. The unique advantages of monodisperse MIL-88A nanoparticles over polydisperse ones are further demonstrated in terms of in vitro magnetic resonance imaging (MRI), cellular uptake, and drug-carrying properties.

8.
Plant Physiol ; 187(4): 2134-2155, 2021 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-34618032

RESUMO

Grain legumes such as pea (Pisum sativum L.) are highly valued as a staple source of protein for human and animal nutrition. However, their seeds often contain limited amounts of high-quality, sulfur (S) rich proteins, caused by a shortage of the S-amino acids cysteine and methionine. It was hypothesized that legume seed quality is directly linked to the amount of organic S transported from leaves to seeds, and imported into the growing embryo. We expressed a high-affinity yeast (Saccharomyces cerevisiae) methionine/cysteine transporter (Methionine UPtake 1) in both the pea leaf phloem and seed cotyledons and found source-to-sink transport of methionine but not cysteine increased. Changes in methionine phloem loading triggered improvements in S uptake and assimilation and long-distance transport of the S compounds, S-methylmethionine and glutathione. In addition, nitrogen and carbon assimilation and source-to-sink allocation were upregulated, together resulting in increased plant biomass and seed yield. Further, methionine and amino acid delivery to individual seeds and uptake by the cotyledons improved, leading to increased accumulation of storage proteins by up to 23%, due to both higher levels of S-poor and, most importantly, S-rich proteins. Sulfate delivery to the embryo and S assimilation in the cotyledons were also upregulated, further contributing to the improved S-rich storage protein pools and seed quality. Overall, this work demonstrates that methionine transporter function in source and sink tissues presents a bottleneck in S allocation to seeds and that its targeted manipulation is essential for overcoming limitations in the accumulation of high-quality seed storage proteins.


Assuntos
Membrana Celular/metabolismo , Metionina/metabolismo , Floema/metabolismo , Pisum sativum/metabolismo , Folhas de Planta/metabolismo , Transporte Proteico/fisiologia , Sementes/metabolismo , Plantas Geneticamente Modificadas
9.
Plant J ; 101(1): 217-236, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31520495

RESUMO

Seed development largely depends on the long-distance transport of sucrose from photosynthetically active source leaves to seed sinks. This source-to-sink carbon allocation occurs in the phloem and requires the loading of sucrose into the leaf phloem and, at the sink end, its import into the growing embryo. Both tasks are achieved through the function of SUT sucrose transporters. In this study, we used vegetable peas (Pisum sativum L.), harvested for human consumption as immature seeds, as our model crop and simultaneously overexpressed the endogenous SUT1 transporter in the leaf phloem and in cotyledon epidermal cells where import into the embryo occurs. Using this 'Push-and-Pull' approach, the transgenic SUT1 plants displayed increased sucrose phloem loading and carbon movement from source to sink causing higher sucrose levels in developing pea seeds. The enhanced sucrose partitioning further led to improved photosynthesis rates, increased leaf nitrogen assimilation, and enhanced source-to-sink transport of amino acids. Embryo loading with amino acids was also increased in SUT1-overexpressors resulting in higher protein levels in immature seeds. Further, transgenic plants grown until desiccation produced more seed protein and starch, as well as higher seed yields than the wild-type plants. Together, the results demonstrate that the SUT1-overexpressing plants with enhanced sucrose allocation to sinks adjust leaf carbon and nitrogen metabolism, and amino acid partitioning in order to accommodate the increased assimilate demand of growing seeds. We further provide evidence that the combined Push-and-Pull approach for enhancing carbon transport is a successful strategy for improving seed yields and nutritional quality in legumes.


Assuntos
Floema/metabolismo , Sementes/metabolismo , Sacarose/metabolismo , Carbono/metabolismo , Regulação da Expressão Gênica de Plantas , Nitrogênio/metabolismo , Pisum sativum/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo
10.
Small ; 17(10): e2007090, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33464716

RESUMO

Dual phototherapy, including photodynamic therapy (PDT) and photothermal therapy (PTT), has shown a great prospect in cancer treatment. However, its therapeutic effect is restricted by the depth of light penetration in tissue and tumor hypoxia environment. Herein, inspired by the specific response of nanozymes to the tumor microenvironment (TME), a simple and versatile nanozyme-mediated synergistic dual phototherapy nanoplatform (denoted as FePc/HNCSs) is constructed using hollow nitrogen-doped carbon nanospheres (HNCSs) and iron phthalocyanine (FePc). FePc/HNCSs simultaneously exhibit peroxidase (POD)- and catalase (CAT)-like activities, which not only can convert endogenous hydrogen peroxide (H2 O2 ) into highly toxic hydroxyl radicals (•OH) for catalytic therapy, but also decompose H2 O2 to oxygen (O2 ) to enhance O2 -dependent PDT. In addition, their enzyme-like activities are significantly enhanced under light irradiation. Combining with the excellent photothermal effect, FePc/HNCSs realize a high tumor inhibition rate of 96.3%. This strategy opens a new horizon for exploring a more powerful tumor treatment nanoplatform.


Assuntos
Neoplasias , Fotoquimioterapia , Humanos , Neoplasias/tratamento farmacológico , Fototerapia , Hipóxia Tumoral , Microambiente Tumoral
11.
Bioorg Med Chem Lett ; 48: 128271, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34284105

RESUMO

Cinnoline is a potential pharmacophore which has rarely been reported for uses as PI3K inhibitors. In this study, a series of cinnoline derivatives were developed as PI3K inhibitors and evaluated for enzymatic and cellular activities. Most compounds displayed nanomolar inhibitory activities against PI3Ks, among which 25 displayed high LLE and micromolar inhibitory potency against three human tumor cell lines (IC50 = 0.264 µM, 2.04 µM, 1.14 µM).


Assuntos
Antineoplásicos/farmacologia , Descoberta de Drogas , Compostos Heterocíclicos com 2 Anéis/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Compostos Heterocíclicos com 2 Anéis/síntese química , Compostos Heterocíclicos com 2 Anéis/química , Humanos , Estrutura Molecular , Inibidores de Fosfoinositídeo-3 Quinase/síntese química , Inibidores de Fosfoinositídeo-3 Quinase/química , Relação Estrutura-Atividade
12.
Bioorg Chem ; 117: 105405, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34649154

RESUMO

Breast cancer is the cancer with the highest incidence all over the world. Phosphatidylinositol 3-kinase is an important regulator of intracellular signaling pathways, which is frequently mutated and overexpressed in majority of human breast cancers, and the inhibition of PI3K has been considered as a promising approach for the treatment of the cancer. Here, we report our design and synthesis of new 7-azaindole derivatives as PI3K inhibitors through the scaffold hopping strategy. By varying the groups at the 3-position of 7-azaindole, we identified a series of potent PI3K inhibitors, whose antiproliferative activities against two human breast cancer MCF-7 and MDA-MB-231 cell lines were evaluated. Representative derivatives FD2054 and FD2078 showed better activity than BKM120 in antiproliferation, reduced the levels of phospho-AKT and induced cell apoptosis. All these results suggested that FD2054 and FD2078 are potent PI3K inhibitors that could be considered as potential candidates for the development of anticancer agents.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Indóis/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Antineoplásicos/química , Neoplasias da Mama/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Indóis/química , Células MCF-7 , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/química , Inibidores de Proteínas Quinases/química
13.
J Med Virol ; 92(8): 1221-1230, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31900950

RESUMO

Citrullinated histone H3 (H3Cit) is the product of the conversion of peptidylarginine to citrulline in histone H3. We evaluated the H3Cit level in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) tissues and assessed its association with Beclin1 messenger RNA (mRNA) (a key autophagic regulator). The level of H3Cit was detected by a capture enzyme-linked immunosorbent assay, while Beclin1 mRNA was determined by real-time polymerase chain reaction in 80 HBV-related patients with HCC. We found that the mean level of H3Cit was 72.25 ng/mg in HCC and 44.02 ng/mg in nontumor tissues. The mean HCC/nontumor ratio of Beclin1 mRNA was higher (0.096) in tumor samples than in nontumor specimens (0.056). Specifically, Beclin1 mRNA was elevated in 51 HCC cases (63.75%) and decreased in 29 cases (36.25%). Moreover, the levels of H3Cit and Beclin1 mRNA were significantly associated with vascular invasion and serum AFP levels. A shorter survival (19 months) was associated with a high H3Cit level. We also found increased levels of Beclin1 mRNA in the H3Cit (high) group compared with the H3Cit (low) group. The results implied that elevated histone H3 citrullination is associated with increased Beclin1 expression during the development of HBV-related HCC.


Assuntos
Proteína Beclina-1/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virologia , Citrulinação , Histonas/química , Neoplasias Hepáticas/genética , Adulto , Idoso , China , Feminino , Vírus da Hepatite B/patogenicidade , Humanos , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/análise
14.
J Exp Bot ; 71(15): 4495-4511, 2020 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-32188989

RESUMO

Nitrogen (N)-fixing soybean plants use the ureides allantoin and allantoic acid as major long-distance transport forms of N, but in non-fixing, non-nodulated plants amino acids mainly serve in source-to-sink N allocation. However, some ureides are still synthesized in roots of non-fixing soybean, and our study addresses the role of ureide transport processes in those plants. In previous work, legume ureide permeases (UPSs) were identified that are involved in cellular import of allantoin and allantoic acid. Here, UPS1 from common bean was expressed in the soybean phloem, which resulted in enhanced source-to-sink transport of ureides in the transgenic plants. This was accompanied by increased ureide synthesis and elevated allantoin and allantoic acid root-to-sink transport. Interestingly, amino acid assimilation, xylem transport, and phloem partitioning to sinks were also strongly up-regulated. In addition, photosynthesis and sucrose phloem transport were improved in the transgenic plants. These combined changes in source physiology and assimilate partitioning resulted in increased vegetative growth and improved seed numbers. Overall, the results support that ureide transport processes in non-fixing plants affect source N and carbon acquisition and assimilation as well as source-to-sink translocation of N and carbon assimilates with consequences for plant growth and seed development.


Assuntos
Fabaceae , Glycine max , Nitrogênio , Floema , Sementes , Glycine max/genética
15.
Med Sci Monit ; 26: e924325, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33046685

RESUMO

BACKGROUND Ultrasound (US) is the preferred imaging method for cryptorchidism, but most guidelines indicate that its value is questionable. The aim of this study was to evaluate the clinical value of ultrasonic mobility and testicular atrophy index (TAI) based on three­dimensional US (3DUS) in preoperative and postoperative assessment of the undescended testis. MATERIAL AND METHODS Data from 158 children with unilateral extraperitoneal cryptorchidism were collected and their diagnoses were surgically confirmed. They were divided into different age groups and into 2 ultrasonic mobility groups: the mobile group (MG) and the restricted group (RG). Differences in sonographic characteristics between different groups were compared. Three-dimensional ultrasound performed with virtual organ computer-aided analysis (VOCAL) was used to determined preoperative and postoperative TAI and the reliability of TAI was analyzed. RESULTS Measurement of testicular volume with the VOCAL method was significantly more reliable than that done with the two-dimensional Lambert method. In all age groups, preoperative testicular volumes were smaller than that in the contralateral scrotal testis and postoperatively, they increased steadily. Both preoperative and postoperative TAI were higher in the RG than in the MG. In the MG, postoperative TAI decreased significantly in all age groups. In the RG, in contrast, effective volume growth was only achieved in patients who had undergone surgery before they reached age 1 year. CONCLUSIONS TAI values determined with 3DUS using the VOCAL technique objectively reflect recovery of testicular volume following surgery for undescended testicle. Ultrasonic mobility evaluation is beneficial for clinical management of the condition.


Assuntos
Criptorquidismo , Ecocardiografia Tridimensional , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios , Testículo , Criança , Criptorquidismo/diagnóstico por imagem , Criptorquidismo/cirurgia , Humanos , Masculino , Tamanho do Órgão , Estudos Retrospectivos , Testículo/diagnóstico por imagem , Testículo/cirurgia
16.
BMC Infect Dis ; 17(1): 715, 2017 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-29126397

RESUMO

BACKGROUND: There is global health concern that the mass movement of pilgrims to and from Mecca annually could contribute to the international spread of Middle East Respiratory Syndrome Coronavirus (MERS-CoV). In China, about 11,000 Muslim pilgrims participate in the Hajj gathering in Mecca annually. This is the first report of MERS-CoV and respiratory virus molecular screening of returning pilgrims at points of entry in China from 2013 to 2015. METHODS AND RESULTS: A total of 847 returning Hajj pilgrims participated in this study. The test results indicated that of the travelers, 34 tested positive for influenza A virus, 14 for influenza B virus, 4 for metapneumo virus, 2 for respiratory syncytial virus, and 3 for human coronavirus. There was a significant difference in the rates of positive and negative influenza virus tests between Hajj pilgrims with symptoms and those without. The detection rates of influenza virus were not significantly different among the three years studied, at 5.3, 6.0 and 6.3% for 2013, 2014 and 2015, respectively. DISCUSSION AND CONCLUSION: The MERS-CoV and respiratory viruses detection results at points of entry in China from 2013 to 2015 indicated that there were no MERS-CoV infection but a 5.7% positive influenza viruses in returning Chinese pilgrims.


Assuntos
Infecções por Coronavirus/epidemiologia , Influenza Humana/epidemiologia , Coronavírus da Síndrome Respiratória do Oriente Médio/isolamento & purificação , Orthomyxoviridae/isolamento & purificação , China/epidemiologia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , Humanos , Influenza Humana/diagnóstico , Influenza Humana/virologia , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Orthomyxoviridae/genética , RNA Viral/genética , RNA Viral/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Vírus Sincicial Respiratório Humano/genética , Vírus Sincicial Respiratório Humano/isolamento & purificação , Inquéritos e Questionários
17.
Microbiol Res ; 279: 127570, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38096690

RESUMO

Type VI secretion system (T6SS) plays an essential role in interspecies interactions and provides an advantage for a strain with T6SS in multispecies biofilms. However, how T6SS drives the bacterial community structure and functions in multispecies biofilms still needs to be determined. Using gene deletion and Illumina sequencing technique, we estimated bacterial community responses in multispecies biofilms to T6SS by introducing T6SS-containing Pseudomonas putida KT2440. Results showed that the niche structure shifts of multispecies biofilms were remarkably higher in the presence of T6SS than in the absence of T6SS. The presence of T6SS significantly drove the variation in microbial composition, reduced the alpha-diversity of bacterial communities in multispecies biofilms, and separately decreased and increased the relative abundance of Proteobacteria and Bacteroidota. Co-occurrence network analysis with inferred putative bacterial interactions indicated that P. putida KT2440 mainly displayed strong negative associations with the genera of Psychrobacter, Cellvibrio, Stenotrophomonas, and Brevundimonas. Moreover, the function redundancy index of the bacterial community was strikingly higher in the presence of T6SS than in the absence of T6SS, regardless of whether relative abundances of bacterial taxa were inhibited or promoted. Remarkably, the increased metabolic network similarity with T6SS-containing P. putida KT2440 could enhance the antibacterial activity of P. putida KT2440 on other bacterial taxa. Our findings extend knowledge of microbial adaptation strategies to potential bacterial weapons and could contribute to predicting biodiversity loss and change in ecological functions caused by T6SS.


Assuntos
Pseudomonas putida , Sistemas de Secreção Tipo VI , Sistemas de Secreção Tipo VI/genética , Sistemas de Secreção Tipo VI/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Pseudomonas putida/genética , Pseudomonas putida/metabolismo , Deleção de Genes , Biofilmes
18.
Exp Ther Med ; 25(1): 29, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36561617

RESUMO

Esophageal cancer has high incidence rate in China. Neoadjuvant chemoradiotherapy (nCRT) has become the standard treatment for esophageal squamous cell carcinoma (ESCC). However, there are few reliable epigenetic parameters for patients with ESCC undergoing neoadjuvant therapy. Genomic extract from tumor tissue was amplified and sequenced using the Illumina HiSeq4000 to quantify genes associated methylation or hydromethylation in 12 patients with ESCC undergoing nCRT. The genome-wide hydroxymethylation were analyzed by methylated and hydroxymethylated DNA immunoprecipitation sequencing by MACS2 software and UCSC RefSeq database. Abnormal DNA methylation was statistically different between nCRT-well (showed a pathological complete response to nCRT) and nCRT-poor (showed incomplete pathological response to nCRT) patients. Levels of ten-eleven translocation 1, 2 and 3 mRNA and protein were higher in tumor tissue in nCRT-well group patients than in nCRT-poor group patients. Illumina HiSeq 4000 sequencing identified 2925 hypo-differentially hydroxymethylated region (DhMRs) and 292 hyper-DhMRs in promoter between nCRT-well and nCRT-poor patients. Biological processes associated with hyper-DhMRs included 'snRNA processing', 'hormone-mediated signaling pathway' and 'cellular response'. Metabolic processes were associated with hypo-DhMRs. These data may explain the functional response to nCRT in patients with abnormal promoter of methylation gene-associated mRNA expression. The present results implied that hyper-DhMRs and hypo-DhMRs affect molecular pathways, such as hippo and Notch signaling pathways, highlighting epigenetic modifications associated with clinical response to nCRT in patients with esophageal cancer.

19.
Front Pediatr ; 11: 1226508, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37780044

RESUMO

Introduction: The role of vitamin C in pediatric fractures has not received much attention, although it is known to be a factor in osteoporotic fractures in the elderly. This case-control study aimed to investigate the changes in serum vitamin C levels among children with limb fractures. Methods: We recruited 325 children with and 316 children without limb fractures hospitalized between January 2021 and December 2021. Following admission, basic demographic data of all participants were collected, and fasting serum vitamin C levels were determined using ultra-high-performance liquid chromatography-tandem mass spectrometry. Results: The mean age of the fracture group was 5.1 years (95% CI, 4.83-5.33). The serum vitamin C levels in the fracture group (4.48 µg/ml) were significantly lower than those in the control group (8.38 µg/ml) (p < 0.0001). Further subgroup analysis of the fracture group revealed that serum vitamin C levels decreased significantly after 4 years of age and there was a significant difference in the duration after injury between <6 and >6 h (p = 0.0224). Spearman's rank correlation coefficient suggested that age and vitamin C levels were negatively correlated in the fracture group. Conclusion: In general, children with limb fractures had lower serum vitamin C levels, especially those aged 4 years and over.

20.
Ultrasonics ; 134: 107103, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37437399

RESUMO

This study aims to investigate the feasibility of combined segmentation for the separation of lesions from non-ablated regions, which allows surgeons to easily distinguish, measure, and evaluate the lesion area, thereby improving the quality of high-intensity focused-ultrasound (HIFU) surgery used for the non-invasive tumor treatment. Given that the flexible shape of the Gamma mixture model (GΓMM) fits the complex statistical distribution of samples, a method combining the GΓMM and Bayes framework is constructed for the classification of samples to obtain the segmentation result. An appropriate normalization range and parameters can be used to rapidly obtain a good performance of GΓMM segmentation. The performance values of the proposed method under four metrics (Dice score: 85%, Jaccard coefficient: 75%, recall: 86%, and accuracy: 96%) are better than those of conventional approaches including Otsu and Region growing. Furthermore, the statistical result of sample intensity indicates that the finding of the GΓMM is similar to that obtained by the manual method. These results indicate the stability and reliability of the GΓMM combined with the Bayes framework for the segmentation of HIFU lesions in ultrasound images. The experimental results show the possibility of combining the GΓMM with the Bayes framework to segment lesion areas and evaluate the effect of therapeutic ultrasound.


Assuntos
Algoritmos , Hipertermia Induzida , Teorema de Bayes , Reprodutibilidade dos Testes , Ultrassonografia/métodos , Processamento de Imagem Assistida por Computador/métodos
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