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1.
Biomed Chromatogr ; : e5895, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806448

RESUMO

The present research demonstrated that an integrated multi-system based on the assays of lipid-lowering and expectorant effects was used to screen quality markers of an edible and medical material-the blossom of Citrus aurantium L. var. amara Engl. (BCAVA)-and a portion of active constituents were quantified in multiple batches to provide scientific data to establish a quality standard for BCAVA. Mouse models were developed to evaluate the lipid-lowering and expectorant effects, facilitating the investigation of medicinal parts through different polar extractions of BCAVA. Subsequently, ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was utilized for the in vivo and in vitro identification of chemical profiles within the medicinal parts of BCAVA. This methodological approach led to the selection and quantification of several active compounds from 21 batches of BCAVA sourced from different geographical regions samples. Notably, the ethanol extract of BCAVA exhibited significant lipid-lowering and expectorant effects while 183 compounds were identified in vitro and 109 in vivo, respectively. Then, five key ingredients were quantified, and the quantitative data were subjected to statistical analysis to discriminate between samples from various geographical regions. Overall, the findings underscore the significance of an integrated, assay-based approach for the characterization and quality assessment of BCAVA.

2.
Angew Chem Int Ed Engl ; 63(26): e202404244, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38639067

RESUMO

Ratiometric afterglow luminescent (AGL) probes are attractive for in vivo imaging due to their high sensitivity and signal self-calibration function. However, there are currently few ratiometric AGL probes available for imaging enzymatic activity in living organisms. Here, we present an energy diversion (ED) strategy that enables the design of an enzyme-activated ratiometric AGL probe (RAG-RGD) for in vivo afterglow imaging. The ED process provides RAG-RGD with a radiative transition for an 'always on' 520-nm AGL signal (AGL520) and a cascade three-step energy transfer (ET) process for an 'off-on' 710-nm AGL signal (AGL710) in response to a specific enzyme. Using matrix metalloproteinase-2 (MMP-2) as an example, RAG-RGD shows a significant ~11-fold increase in AGL710/AGL520 toward MMP-2. This can sensitively detect U87MG brain tumors through ratiometric afterglow imaging of MMP-2 activity, with a high signal-to-background ratio and deep imaging depth. Furthermore, by utilizing the self-calibration effect of ratiometric imaging, RAG-RGD demonstrated a strong negative correlation between the AGL710/AGL520 value and the size of orthotopic U87MG tumor, enabling accurate monitoring of orthotopic glioma growth in vivo. This ED process may be applied for the design of other enzyme-activated ratiometric afterglow probes for sensitive afterglow imaging.


Assuntos
Metaloproteinase 2 da Matriz , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 2 da Matriz/análise , Humanos , Animais , Linhagem Celular Tumoral , Camundongos , Luminescência
3.
Angew Chem Int Ed Engl ; 63(4): e202314039, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38055211

RESUMO

We report here a tumor-pretargted theranostic approach for multimodality imaging-guided synergistic cancer PDT by cascade alkaline phosphatase (ALP)-mediated in situ self-assembly and bioorthogonal inverse electron demand Diels-Alder (IEDDA) reaction. Using the enzymatic catalysis of ALP that continuously catalyses the dephosphorylation and self-assembly of trans-cyclooctene (TCO)-bearing P-FFGd-TCO, a high density of fluorescent and magnetic TCO-containing nanoparticles (FMNPs-TCO) can be synthesized and retained on the membrane of tumor cells. They can act as 'artificial antigens' amenable to concurrently capture lately administrated tetrazine (Tz)-decorated PS (775NP-Tz) and carbonic anhydrase (CA) inhibitor (SA-Tz) via the fast IEDDA reaction. This two-step pretargeting process can further induce FMNPs-TCO regrowth into microparticles (FMNPs-775/SA) directly on tumor cell membranes, which is analyzed by bio-SEM and fluorescence imaging. Thus, efficient enrichment of both SA-Tz and 775NP-Tz in tumors can be achieved, allowing to alleviate hypoxia by continuously inhibiting CA activity and improving PDT of tumors. Findings show that subcutaneous HeLa tumors could be completely eradicated and no tumor recurred after irradiation with an 808 nm laser (0.33 W cm-2 , 10 min). This pretargeted approach may be applied to enrich other therapeutic agents in tumors to improve targeted therapy.


Assuntos
Neoplasias , Fármacos Fotossensibilizantes , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Inibidores da Anidrase Carbônica/farmacologia , Compostos Radiofarmacêuticos , Medicina de Precisão , Linhagem Celular Tumoral , Reação de Cicloadição , Ciclo-Octanos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico
4.
J Am Chem Soc ; 145(50): 27838-27849, 2023 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-38059465

RESUMO

Hydrogen sulfide (H2S) has shown promise for gas therapy. However, it is still controversial whether H2S can remodel the tumor microenvironment (TME) and induce robust antitumor immunity. Here, a tumor-targeting and TME-responsive "smart" lipid nanoparticle (1-JK-PS-FA) is presented, which is capable of delivering and releasing H2S specifically in tumor tissues for on-demand H2S gas and photodynamic immunotherapy. 1-JK-PS-FA enables a burst release of H2S in the acidic TME, which promptly reduces the embedded organic electrochromic materials and consequently switches on near-infrared fluorescence and photodynamic activity. Furthermore, we found that high levels of H2S can reprogram the TME by reducing tumor interstitial fluid pressure, promoting angiogenesis, increasing vascular permeability, ameliorating hypoxia, and reducing immunosuppressive conditions. This leads to increased tumor uptake of 1-JK-PS-FA, thereby enhancing PDT efficacy and eliciting strong immunogenic cell death during 808 nm laser irradiation. Therefore, 1-JK-PS-FA permits synergistic H2S gas and photodynamic immunotherapy, effectively eradicating orthotopic breast tumors and preventing tumor metastasis and recurrence. This work showcases the capacity of H2S to reprogram the TME to enhance H2S gas and immunotherapy.


Assuntos
Neoplasias Mamárias Animais , Nanopartículas , Neoplasias , Fotoquimioterapia , Animais , Microambiente Tumoral , Imunoterapia , Transporte Biológico , Linhagem Celular Tumoral
5.
Pestic Biochem Physiol ; 196: 105621, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37945257

RESUMO

Biocontrol of subterranean termites is largely impeded by their social immune responses. Studies on biocontrol agents combined with natural insecticides and their possible effects on the immune defense mechanisms of termites are limited. In this study, we investigated the effects of a combined biocontrol strategy using a plant-derived insect ATPase inhibitor, α-terpineol, with the entomopathogenic nematodes (EPNs) Steinernema carpocapsae against the subterranean termite Coptotermes formosanus Shiraki. Survival assays showed that even a low lethal concentration of α-terpineol significantly increased the EPNs-induced virulence in C. formosanus. α-terpineol treatment majorly inhibited the activity of Na+- K+- ATPase, which disturbed the EPNs-induced enhancement of locomotor activity and grooming behavior in termites treated with the combined strategy. Furthermore, the combination treatment had a synergistic inhibitory effect on innate immune responses in C. formosanus, which were measured as changes in the expression of immune-related genes and activities of immune system enzymes. In conclusion, α-terpineol can weaken the immune defense of termites against EPNs at low lethal concentrations, and is a suitable non-synthetic insecticide to prove the biocontrol efficiency of EPNs on C. formosanus. This study provides a theoretical basis and technical reference for a novel biocontrol strategy that promises to overcome the problems of host immune defense in termites.


Assuntos
Inseticidas , Isópteros , Nematoides , Animais , Isópteros/fisiologia , Virulência , Inseticidas/farmacologia , Adenosina Trifosfatases
6.
Pak J Med Sci ; 39(6): 1774-1778, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37936771

RESUMO

Objective: To investigate the analgesic effect of thoracic paravertebral block (TPVB) in patients undergoing thoracoscopic lobectomy under general anesthesia (GA). Methods: Clinical records of 82 patients who underwent thoracoscopic lobectomy under GA from October 2021 to October 2022 in the General Hospital of Southern Theater Command were retrospectively analyzed. The patients were divided into two groups according to the method of anesthesia used: general anesthesia group (Group-G, n=37), and TPVB plus GA group (Group-T, n=45). The analgesic effect, mean arterial pressure (MAP), heart rate (HR) and the rate of adverse events in both groups were compared. Results: Visual analogue scale (VAS) scores of patients in Group-T at 12h, 24h and 48h after the operation were significantly lower compared to Group-G (P<0.05). MAP and HR the time of tracheal intubation induction (T1), single lung ventilation (T2), skin incision (T3), operation completion (T4), and 20 minutes after the extubation (T5) were lower in both groups compared to T0, and were significantly higher in Group-T compared to Group-G (P<0.05). The rate of adverse events in Group-T was 6.67%, significantly lower compared to Group-G (24.32%) (P<0.05). Conclusions: TPVB combined with GA can improve the analgesic effect, improve MAP and HR during the operation, and reduce the incidence of adverse events in patients undergoing thoracoscopic lobectomy.

7.
Angew Chem Int Ed Engl ; 62(10): e202217055, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36602292

RESUMO

Tumor-targeted and stimuli-activatable nanosensitizers are highly desirable for cancer theranostics. However, designing smart nanosensitizers with multiple imaging signals and synergistic therapeutic activities switched on is challenging. Herein, we report tumor-targeted and redox-activatable nanosensitizers (1-NPs) for sono-photodynamic immunotherapy of tumors by molecular co-assembly and redox-controlled disassembly. 1-NPs show a high longitudinal relaxivity (r1 =18.7±0.3 mM-1 s-1 ), but "off" dual fluorescence (FL) emission (at 547 and 672 nm), "off" sono-photodynamic therapy and indoleamine 2,3-dioxygenase 1 (IDO1) inhibition activities. Upon reduction by glutathione (GSH), 1-NPs rapidly disassemble and remotely release small molecules 2-Gd, Zn-PPA-SH and NLG919, concurrently switching on (1) dual FL emission, (2) sono-photodynamic therapy and (3) IDO1 inhibition activities. After systemic injection, 1-NPs are effective for bimodal FL and magnetic resonance (MR) imaging-guided sono-photodynamic immunotherapy of orthotropic breast and brain tumors in mice under combined ultrasound (US) and 671-nm laser irradiation.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Animais , Camundongos , Fotoquimioterapia/métodos , Neoplasias/tratamento farmacológico , Fluorescência , Oxirredução , Imunoterapia , Linhagem Celular Tumoral , Fármacos Fotossensibilizantes/uso terapêutico
8.
Chemistry ; 28(70): e202202457, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36109342

RESUMO

10,11-Bis[bis(4-dimethylaminophenyl)methylene]dibenzo[bf]thiepin (1) and -oxepin (2) were prepared as stable yellow crystalline compounds, which are the cyclic analogues of electron-donating hexaarylbutadienes. Upon two-electron oxidation, they are reversibly transformed into the title dications (12+ and 22+ ) exhibiting near-infrared (NIR) absorptions, which were also isolated as stable salts. These redox pairs can serve as new entries into less well-explored organic NIR-electrochromic systems, and the separation of redox peaks (electrochemical bistability) was attained for 1/12+ and 2/22+ , thanks to drastic geometrical changes between neutral and dicationic states, as revealed by a series of X-ray analyses. Thiepin-S,S-dioxide analogue (3/32+ ) exhibits quite similar dynamic redox behavior due to nonaromatic nature of the dibenzothiepin and -oxepin unit in 12+ and 22+ , whereas the thiepin-S-oxide derivative (4/42+ ) does not exhibit bistability due to the smaller change in geometry upon electron transfer, showing that a subtle change of a bridging atom in the central seven-membered ring can modify the redox properties.

9.
Ecotoxicol Environ Saf ; 232: 113240, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35091298

RESUMO

Biochar has attracted worldwide attention owing to its potential for mitigating greenhouse gas emissions, improving soil properties, increasing plant growth and so on. While, the assessment of a substantial amount of security is required to determine before biochar is more extensively applied. Our goal was to evaluate the security of biochar by determining the effect of biochar on the preference of soil arthropods for microhabitats. In this study, we examined the effect of varying amounts of biochar on the preference of the Formosan subterranean termite (Coptotermes formosanus) to microhabitats. In addition, we analyzed key soil characteristics to explore their relevance to the termite preferences. Our results found that when compared with 0% (control soil), there was no preference when 2.5% and 5% of biochar were applied. The application of >5% biochar repelled the termites, which then left these soils. Their fresh weight and rates of survival also decreased. The soil pH increased, but the humidity decreased when >5% of biochar was applied. Soil bacteria composition when biochar was amended at 20% also differed from 0% and 2.5% applications. The relative abundance of Cellvibrio and Flavisolibacter in 20% were significantly higher than 0% and 2.5%, while the relative abundance of Burkholderia, Candidatus_Solibacter, Dyella, Edaphobacter, Fulvimonas and Occallatibacter were significantly lower than them. And the functional results predicted by Bugbase suggested that biochar application can cause an increase in the soil potentially pathogen phenotype. In conclusion, our research indicated that biochar can affect the preference of termites for microhabitats and changes in the characteristics of soil might cause changes in these preferences. In addition, our results suggest that soil that has been amended with >10% biochar has the potential to control termites.


Assuntos
Baratas , Isópteros , Animais , Carvão Vegetal , Solo
10.
Angew Chem Int Ed Engl ; 61(37): e202209248, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-35851521

RESUMO

Reversible imaging probes that allow for the dynamic visualization of the redox cycle between hydroxyl radical (⋅OH) and hydrogen sulfide (H2 S) are vital to probe the redox imbalance-involved pathological process in vivo. Herein, we report a reversible ratiometric photoacoustic (PA) imaging nanoprobe (1-PAIN) for the real-time imaging of ⋅OH/H2 S redox cycle in vivo. 1-PAIN displays a low PA ratio between 690 and 825 nm (PA690 /PA825 ), which significantly increases by ≈5-fold upon oxidation by ⋅OH, and is switched back to the initially low PA690 /PA825 value upon reduction by H2 S. 1-PAIN could dynamically report on the hepatic ⋅OH production in mice during the lipopolysaccharide (LPS)-induced liver inflammation process, and visualize hepatic H2 S generation during the N-acetyl cysteine (NAC)-induced anti-inflammation process. 1-PAIN can act as a useful tool to probe the redox state in living biology, beneficial for the study of redox imbalance-related diseases.


Assuntos
Sulfeto de Hidrogênio , Técnicas Fotoacústicas , Animais , Corantes Fluorescentes , Radical Hidroxila , Fígado/diagnóstico por imagem , Camundongos , Oxirredução , Técnicas Fotoacústicas/métodos , Análise Espectral
11.
Angew Chem Int Ed Engl ; 61(4): e202111759, 2022 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-34791772

RESUMO

Accurate detection of hepatic hydrogen sulfide (H2 S) to monitor H2 S-related enzymes' activity is critical for acute hepatitis diagnosis, but remains a challenge due to the dynamic and transient nature of H2 S. Here, we report a H2 S-activatable near-infrared afterglow/MRI bimodal probe F1-GdNP, which shows an "always-on" MRI signal and "off-on" afterglow signal toward H2 S. F1-GdNP shows fast response, high sensitivity and specificity toward H2 S, permitting afterglow imaging of H2 S and evaluation of cystathionine γ-lyase (CSE)'s activity in living mice. We further employ the high spatial-resolution MRI signal of F1-GdNP to track its delivery and accumulation in liver. Importantly, F1-GdNP offers a high signal-to-background ratio (SBR=86.2±12.0) to sensitively report on the increased hepatic H2 S level in the acute hepatitis mice via afterglow imaging, which correlated well with the upregulated CSE activity in the liver, showcasing the good potential of F1-GdNP for monitoring of acute hepatitis process in vivo.


Assuntos
Corantes Fluorescentes/química , Gadolínio/química , Hepatite/diagnóstico por imagem , Sulfeto de Hidrogênio/análise , Imageamento por Ressonância Magnética , Nanopartículas/química , Animais , Camundongos , Imagem Óptica , Células RAW 264.7
12.
Small ; 17(36): e2101924, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34309199

RESUMO

Enzyme-activatable ratiometric near-infrared (NIR) fluorescent probes enabling noninvasive imaging of enzyme activity in vivo are promising for biomedical research; however, such probes with ratiometric fluorescence emissions both in NIR window under a single NIR light excitation are largely unexplored. Here, a quenched NIR fluorophore of Cy5.5 is integrated with NIR fluorescent poly[2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b']dithiophene)-alt-4,7(2,1,3-benzothiadiazole)] (PCPDTBT)-based semiconducting polymer nanoparticles (SPNs), and an αv ß3 integrin-targeting and matrix metalloproteinase-2 (MMP-2)-activatable ratiometric fluorescent probe (SPN-MMP-RGD) is developed. Under excitation at 660 nm, SPN-MMP-RGD shows "always-on" fluorescence of PCPDTBT (830 nm) and activatable fluorescence of Cy5.5 (690 nm) toward MMP-2, affording a remarkable ≈176-fold enhancement in fluorescence intensity ratio between 690 and 830 nm (I690 /I830 ) for sensitive detection of MMP-2 activity in vitro and in tumor cells. By virtue of ratiometric fluorescence imaging independently of probe's concentration, SPN-MMP-RGD can not only accurately report on MMP-2 levels regarding different tumor sizes, but also noninvasively delineate MMP-2-positive tiny gastric tumors metastasis in vivo. The authors' study reveals the potential of SPN-MMP-RGD for ratiometric fluorescence imaging of MMP-2 activity via combining two independent NIR fluorophores, which can be amenable for the design of other enzyme-activatable ratiometric NIR fluorescent probes for reliable in vivo imaging.


Assuntos
Nanopartículas , Neoplasias Gástricas , Humanos , Metaloproteinase 2 da Matriz , Imagem Óptica , Polímeros
13.
Biochem Biophys Res Commun ; 522(2): 492-498, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-31780262

RESUMO

Sericin, produced in the middle silk gland (MSG) of silkworms, is a group of glue proteins that coat and cement silk fibers. Several genes are known to encode sericin, but their spatiotemporal regulation has yet to be fully elucidated. Here, we report in detail the expression profiles of the promoters of two major sericin-coding genes, Sericin 1 (Ser1)and Sericin 3 (Ser3), by analyzing Gal4/UAS transgenic silkworms. We found that UAS-linked EGFP fluorescence in transgenic silkworms driven by Ser1-Gal4was detected in only the R3, R4 and R5 regions of MSG starting inday-3 fifth-instar larvae and was continuously expressed until silk gland degradation. In transgenic silkworms driven by Ser3-Gal4, EGFP fluorescence was detected at a low level in the R2 region of MSG since the last day of fifth-instar larvae, and the expression increased during the wandering stages and was continuously detected until silk gland degradation. The molecular detection of EGFP expression in each of the Gal4/UAS transgenic silkworms was consistent with fluorescence observations. These findings reveal clear differences in the regulatory characteristics of the promoters of Ser1and Ser3 and provide new insights into the regulatory mechanism of the expression of sericin-coding genes.


Assuntos
Bombyx/genética , Regiões Promotoras Genéticas , Sericinas/genética , Animais , Animais Geneticamente Modificados , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Fluorescência Verde/metabolismo , Larva/genética , Pupa/genética , Sericinas/metabolismo
14.
Mol Genet Genomics ; 295(5): 1227-1237, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32524299

RESUMO

The silk gland of the silkworm Bombyx mori is a specialized organ where silk proteins are efficiently synthesized under precise regulation that largely determines the properties of silk fibers. To understand the genes involved in the regulation of silk protein synthesis, considerable research has focused on the transcripts expressed in silk glands; however, the complete transcriptome profile of this organ has yet to be elucidated. Here, we report a full-length silk gland transcriptome obtained by PacBio single-molecule long-read sequencing technology. In total, 11,697 non-redundant transcripts were identified in mixed samples of silk glands dissected from larvae at five developmental stages. When compared with the published reference, the full-length transcripts optimized the structures of 3002 known genes, and a total of 9061 novel transcripts with an average length of 2171 bp were detected. Among these, 1403 (15.5%) novel transcripts were computationally revealed to be lncRNAs, 8135 (89.8%) novel transcripts were annotated to different protein and nucleotide databases, and 5655 (62.4%) novel transcripts were predicted to have complete ORFs. Furthermore, we found 1867 alternative splicing events, 2529 alternative polyadenylation events, 784 fusion events and 6596 SSRs. This study provides a comprehensive set of reference transcripts and greatly revises and expands the available silkworm transcript data. In addition, these data will be very useful for studying the regulatory mechanisms of silk protein synthesis.


Assuntos
Bombyx/crescimento & desenvolvimento , Perfilação da Expressão Gênica/métodos , Seda/genética , Imagem Individual de Molécula/métodos , Processamento Alternativo , Animais , Bombyx/genética , Regulação da Expressão Gênica no Desenvolvimento , Sequenciamento de Nucleotídeos em Larga Escala , Proteínas de Insetos/genética , Fases de Leitura Aberta , Poliadenilação , RNA Longo não Codificante/genética , Sequenciamento do Exoma
15.
Transgenic Res ; 29(2): 243-251, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31960249

RESUMO

The cytoplasmic actin gene Actin4 (A4) in silkworm (Bombyx mori) was isolated 20 years ago and has a distal promoter upstream of the first exon and a proximal promoter within the first intron; however, how the promoter regulates gene expression has yet to be fully elucidated. Here, we characterized the function and expression of the proximal promoter (named A4IP) by analyzing transgenic Gal4/UAS silkworms, A4IP-Gal4/UAS-EGFP. We demonstrated that A4IP drives the expression of Gal4 and thereby activates UAS-linked EGFP in transgenic silkworms beginning in day-3 embryos through adults. Further detection revealed that EGFP was expressed at a low level in tissues including the trachea, fat body and midgut but was highly expressed in the wing disks/wings and inner epidermis of transgenic silkworms. No EGFP signals were detected in other tissues by western blot assay. Interestingly, EGFP fluorescence had a spot-like distribution on the epidermis of transgenic larvae. These observations are quite different from those in transgenic silkworms driven by the promoter of Actin3 (A3), another cytoplasmic actin gene in B. mori. These findings reveal the expression profiles of the A4IP promoter and provide new insights into the regulatory mechanism of cytoplasmic actin genes in silkworms.


Assuntos
Actinas/metabolismo , Animais Geneticamente Modificados/metabolismo , Bombyx/metabolismo , Epiderme/metabolismo , Regiões Promotoras Genéticas , Transgenes , Asas de Animais/metabolismo , Actinas/genética , Animais , Animais Geneticamente Modificados/genética , Bombyx/genética , Vetores Genéticos , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Íntrons
16.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(3): 334-337, 2020 Mar 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-32386027

RESUMO

The current outbreak of coronavirus disease 2019 (COVID-19) in Wuhan, China, has posed significant threats to international health. By Feb. 20, 2020, 74 576 cases have been confirmed and over 2 118 deaths have reported in the Chinese mainland. Chinese administrations have carried out immediate and prompt measures to stop the spread of the virus. Wuhan city has been shut down since Jan. 23, and more than 30 thousand medical workers have been recruited to Hubei province. Two temporary hospitals were constructed to treat severe pneumonia patients, and 15 mobile cabin hospitals were built to treat mild pneumonia cases. Significant improvement regarding the pathogenesis, epidemiology, and diagnosis and therapy for the COVID-19 has been achieved to stop the spread of the epidemics.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Pneumonia Viral/epidemiologia , COVID-19 , China , Epidemias , Humanos , Pandemias , SARS-CoV-2
17.
Transgenic Res ; 28(5-6): 627-636, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31564030

RESUMO

The silkworm Bombyx mori is a valuable insect that synthesizes bulk amounts of fibroin protein in its posterior silk gland (PSG) and weaves these proteins into silk cocoons. The mechanism by which the fibroin protein is efficiently synthesized and precisely regulated is an important aspect that has yet to be fully elucidated. Here, we describe the regulatory characteristics of the promoters of fibroin protein-encoding genes, namely, fibroin heavy chain (fibH) and fibroin light chain (fibL), using an optimized Gal4/UAS binary system. We found that (1) UAS-linked enhanced green fluorescent protein (EGFP) was effectively activated in the PSGs of Gal4/UAS transgenic silkworms, and fluorescence was continuously detected in the PSGs after complete formation of silk glands. (2) In the PSGs of fourth- and fifth-instar larvae of transgenic silkworms driven by fibL-Gal4 (LG4) or fibH-Gal4 (HG4), EGFP mRNA was detected in only day-3 to day-6 fifth-instar larvae, while the EGFP protein could be detected at each day of both larval stages. (3) High-level expression of Gal4 and UAS-linked EGFP caused a delay in PSG degradation in Gal4/UAS transgenic silkworms. (4) At the early pupal stage, EGFP fluorescence was also detected in fat bodies of Gal4/UAS transgenic silkworms, indicating that the PSG-specific EGFP was transported into fat bodies during PSG degeneration; however, the underlying mechanism needs to be further elucidated. This study provides a modified Gal4/UAS system used for efficient tissue-specific expression of target genes in the PSGs of silkworms and provides new insights into the regulatory characteristics of the promoters of key fibroin protein-encoding genes.


Assuntos
Animais Geneticamente Modificados/genética , Bombyx/genética , Fibroínas/genética , Proteínas de Insetos/genética , Animais , Fibroínas/biossíntese , Proteínas de Fluorescência Verde/genética , Larva/genética , Regiões Promotoras Genéticas/genética , Pupa/genética , Seda/genética , Fatores de Transcrição
18.
J Pharmacol Sci ; 140(1): 14-19, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31113729

RESUMO

Secreted frizzled-related protein (Sfrp) 4 is a protein that involve in cardiac development and several cardiovascular diseases. However, the effect of Sfrp4 in mediating myocardial ischemia/reperfusion injury remains unknown. In this work, adenoviral (Ad)-shSfrp4 adenoviruses was used to knockdown of Sfrp4 in myocardium to examine the role of Sfrp4 in mediating myocardial I/R injury. Knockdown of Sfrp4 in mice attenuated myocardial I/R injury, as indicated by the decrease levels of lactate dehydrogenase and creatine kinase, and increment of ventricular function following I/R injury. Besides, knockdown of Sfrp4 led to a reduction in Bax, active caspase 3, and increase Bcl-2 and c-Myc in cardiac tissue. Knockdown of Sfrp4 lost its protection against I/R injury in mice infected with Ad-dn-AKT. In conclusion, knockdown of Sfrp4 in myocardium attenuated myocardial ischemia and reperfusion injury by AKT signaling pathway.


Assuntos
Apoptose/genética , Técnicas de Silenciamento de Genes , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/fisiologia , Animais , Masculino , Camundongos Endogâmicos C57BL , Miocárdio/metabolismo , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais/genética
19.
Sensors (Basel) ; 20(1)2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31878080

RESUMO

The mechanical dithered ring laser gyro (RLG) effectively overcomes the lock-in effect and ensures the sensitive accuracy of the low angular rate for the gyro. However, in the inertial measurement unit (IMU) system, the dither excitation of three RLGs causes the coupled vibration of the IMU structure, which could seriously limit the measuring accuracy of RLGs. In this paper, the vibration frequency response characteristic of laser gyro IMU is taken as the focus point, and the method of multi-rigid body dynamics is used to establish the dynamic model of IMU suitable for vibration frequency response analysis. On the basis of the model, the multi-degree-of-freedom coupling vibration of IMU with the gyro dither excitation is clearly described. A new IMU dynamic decoupling optimization method is proposed to minimize the coupled vibration frequency response, and compared with the previous optimal design method. The prototype experimental test results show that the coupled vibration of IMU is restrained more effectively by the proposed new method than by the previous optimal design method. Finally, on the basis of this new method, the measuring accuracy of the RLGs in the IMU system is improved, which is quite useful for practical engineering application.

20.
Transgenic Res ; 26(6): 807-815, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28952064

RESUMO

Diapause is a state of developmental arrest that is most often observed in arthropods, especially insects. The domesticated silkworm, Bombyx mori, is a typical insect that enters diapause at an early embryonic stage. Previous studies have revealed that the diapause hormone (DH) signaling molecules, especially the core members DH and DH receptor 1 (DHR1), are crucial for the determination of embryonic diapause in diapause silkworm strains. However, whether they function in non-diapause silkworm strains remains largely unknown. Here, we generated two transgenic lines overexpressing DH or DHR1 genes in a non-diapause silkworm strain, Nistari. Our results showed that developmental expression patterns of DH and DHR1 are quite similar in transgenic silkworms: both genes are highly expressed in the mid to late stages of pupae and are most highly expressed in day-6 pupae but are expressed at very low levels in other developmental stages. Moreover, the overexpression of DH or DHR1 can affect the expression of diapause-related genes but is not sufficient to induce embryonic diapause in their offspring. This study provides new insights into the function of DH and DHR1 in a non-diapause silkworm strain.


Assuntos
Bombyx/genética , Proteínas de Insetos/genética , Neuropeptídeos/genética , Animais , Animais Geneticamente Modificados , Bombyx/fisiologia , Feminino , Regulação da Expressão Gênica , Fenótipo
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