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1.
Brief Bioinform ; 24(2)2023 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-36917170

RESUMO

Metagenomic sequencing (mNGS) is a powerful diagnostic tool to detect causative pathogens in clinical microbiological testing owing to its unbiasedness and substantially reduced costs. Rapid and accurate classification of metagenomic sequences is a critical procedure for pathogen identification in dry-lab step of mNGS test. However, clinical practices of the testing technology are hampered by the challenge of classifying sequences within a clinically relevant timeframe. Here, we present GPMeta, a novel GPU-accelerated approach to ultrarapid pathogen identification from complex mNGS data, allowing users to bypass this limitation. Using mock microbial community datasets and public real metagenomic sequencing datasets from clinical samples, we show that GPMeta has not only higher accuracy but also significantly higher speed than existing state-of-the-art tools such as Bowtie2, Bwa, Kraken2 and Centrifuge. Furthermore, GPMeta offers GPMetaC clustering algorithm, a statistical model for clustering and rescoring ambiguous alignments to improve the discrimination of highly homologous sequences from microbial genomes with average nucleotide identity >95%. GPMetaC exhibits higher precision and recall rate than others. GPMeta underlines its key role in the development of the mNGS test in infectious diseases that require rapid turnaround times. Further study will discern how to best and easily integrate GPMeta into routine clinical practices. GPMeta is freely accessible to non-commercial users at https://github.com/Bgi-LUSH/GPMeta.


Assuntos
Metagenoma , Microbiota , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Metagenômica/métodos , Sensibilidade e Especificidade
2.
Mol Cell ; 67(6): 974-989.e6, 2017 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-28890335

RESUMO

During autophagosome formation in mammalian cells, isolation membranes (IMs; autophagosome precursors) dynamically contact the ER. Here, we demonstrated that the ER-localized metazoan-specific autophagy protein EPG-3/VMP1 controls ER-IM contacts. Loss of VMP1 causes stable association of IMs with the ER, thus blocking autophagosome formation. Interaction of WIPI2 with the ULK1/FIP200 complex and PI(3)P contributes to the formation of ER-IM contacts, and these interactions are enhanced by VMP1 depletion. VMP1 controls contact formation by promoting SERCA (sarco[endo]plasmic reticulum calcium ATPase) activity. VMP1 interacts with SERCA and prevents formation of the SERCA/PLN/SLN inhibitory complex. VMP1 also modulates ER contacts with lipid droplets, mitochondria, and endosomes. These ER contacts are greatly elevated by the SERCA inhibitor thapsigargin. Calmodulin acts as a sensor/effector to modulate the ER contacts mediated by VMP1/SERCA. Our study provides mechanistic insights into the establishment and disassociation of ER-IM contacts and reveals that VMP1 modulates SERCA activity to control ER contacts.


Assuntos
Autofagossomos/enzimologia , Retículo Endoplasmático/enzimologia , Membranas Intracelulares/enzimologia , Proteínas de Membrana/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Animais , Animais Geneticamente Modificados , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/genética , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Proteínas Relacionadas à Autofagia , Células COS , Sistemas CRISPR-Cas , Caenorhabditis elegans/enzimologia , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Chlorocebus aethiops , Genótipo , Células HEK293 , Células HeLa , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Gotículas Lipídicas/metabolismo , Proteínas de Membrana/genética , Proteínas Musculares/metabolismo , Fenótipo , Fosfatos de Fosfatidilinositol/metabolismo , Proteolipídeos/metabolismo , Interferência de RNA , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , Transfecção
3.
J Biol Chem ; 299(2): 102876, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36623729

RESUMO

Aberrant expression of serine/arginine-rich splicing factor 2 (SRSF2) can lead to tumorigenesis, but its molecular mechanism in colorectal cancer is currently unknown. Herein, we found SRSF2 to be highly expressed in human colorectal cancer (CRC) samples compared with normal tissues. Both in vitro and in vivo, SRSF2 significantly accelerated the proliferation of colon cancer cells. Using RNA-seq, we screened and identified 33 alternative splicing events regulated by SRSF2. Knockdown of SLMAP-L or CETN3-S splice isoform could suppress the growth of colon cancer cells, predicting their role in malignant proliferation of colon cancer cells. Mechanistically, the in vivo crosslinking immunoprecipitation assay demonstrated the direct binding of the RNA recognition motif of SRSF2 protein to SLMAP and CETN3 pre-mRNAs. SRSF2 activated the inclusion of SLMAP alternative exon 24 by binding to constitutive exon 25, while SRSF2 facilitated the exclusion of CETN3 alternative exon 5 by binding to neighboring exon 6. Knockdown of SRSF2, its splicing targets SLMAP-L, or CETN3-S caused colon cancer cells to arrest in G1 phase of the cell cycle. Rescue of SLMAP-L or CETN3-S splice isoform in SRSF2 knockdown colon cancer cells could effectively reverse the inhibition of cell proliferation by SRSF2 knockdown through mediating cell cycle progression. Importantly, the percentage of SLMAP exon 24 inclusion increased and CETN3 exon 5 inclusion decreased in CRC samples compared to paired normal samples. Collectively, our findings identify that SRSF2 dysregulates colorectal carcinoma proliferation at the molecular level of splicing regulation and reveal potential splicing targets in CRC patients.


Assuntos
Processamento Alternativo , Neoplasias do Colo , Splicing de RNA , Humanos , Processamento Alternativo/genética , Proliferação de Células/genética , Neoplasias do Colo/fisiopatologia , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Splicing de RNA/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Fatores de Processamento de Serina-Arginina/genética , Fatores de Processamento de Serina-Arginina/metabolismo , Carcinoma/fisiopatologia
4.
J Am Chem Soc ; 146(42): 29017-29027, 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39390739

RESUMO

Chemical synthesis can generate homogeneous glycoproteins with well-defined and modifiable glycan structures at designated sites. The precision and flexibility of the chemical synthetic approach provide a solution to the heterogeneity problem of glycopeptides/glycoproteins obtained through biological approaches. In this study, we reported that the conserved N-glycosylation sequon (Asn-Xaa-Ser/Thr) of glycoproteins can serve as a general site for performing Ser/Thr ligation to achieve N-linked glycoprotein synthesis. We developed an N + 2 strategy to prepare the corresponding glycopeptide salicylaldehyde esters for Ser/Thr ligation and demonstrated that Ser/Thr ligation at the sequon was not affected by the steric hindrance brought about by the large-sized glycan structures. The effectiveness of this strategy was showcased by the total synthesis of the glycosylated receptor-binding domain (RBD) of the SARS-CoV-2 spike protein.


Assuntos
Glicopeptídeos , Glicoproteínas , Glicosilação , Glicopeptídeos/química , Glicopeptídeos/síntese química , Glicoproteínas/química , Glicoproteínas/síntese química , Glicoproteína da Espícula de Coronavírus/química , Humanos , Aldeídos/química
5.
Opt Express ; 32(2): 1501-1511, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297700

RESUMO

In this study, we designed a self-focused ultrasonic transducer made of polyvinylidene fluoride (PVDF). This transducer involves a back-reflector, which is modeled after tapetum lucidum in the eyes of some nocturnal animals. The bionic structure reflects the ultrasound, which passes through the PVDF membrane, back to PVDF and provides a second chance for the PVDF to convert the ultrasound to electric signals. This design increases the amount of ultrasound absorbed by the PVDF, thereby improving the detection sensitivity. Both ultrasonic and photoacoustic (PA) experiments were conduct to characterize the performance of the transducer. The results show that the fabricated transducer has a center frequency of 13.07 MHz, and a bandwidth of 96% at -6 dB. With an acoustic numerical aperture (NA) of 0.64, the transducer provides a lateral resolution of 140µm. Importantly, the bionic design improves the detection sensitivity of the transducer about 30%. Finally, we apply the fabricated transducer to optical-resolution (OR) and acoustic-resolution photoacoustic microscopy (AR-PAM) to achieve multiscale-resolution PA imaging. Imaging of the bamboo leaf and the leaf skeleton demonstrates that the proposed transducer can provide high spatial resolution, better imaging intensity and contrast. Therefore, the proposed transducer design will be useful to enhance the performance of multiscale-resolution PAM.

6.
Int Ophthalmol ; 44(1): 203, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671195

RESUMO

PURPOSE: This study aimed to observe the tilt and decentration of multifocal intraocular lens (IOL) with optic capture in Berger space within 2 years after pediatric cataract surgery. METHODS: This is a prospective observational study. The implantation of multifocal IOL (Tecnis ZMB00) with optic capture in Berger space was performed on 33 patients (48 eyes) with pediatric cataract at Qingdao Eye Hospital. Tilt and decentration of IOL was measured using Scheimpflug system (Pentacam) at 1 month and 2 years postoperatively. RESULTS: All the multifocal IOLs were successfully implanted in Berger space with optic capture and no visually significant complications were detected during the follow-up. The mean tilt of IOLs was 2.779° ± 0.950° in the vertical plane and 2.399° ± 0.898° in the horizontal plane at 1 month postoperatively, and the mean length of the decentration was 0.207 ± 0.081 mm in vertical plane and 0.211 ± 0.090 mm in the horizontal plane. Compared with 1 month after surgery, the angle of tilt decreased by a mean of 0.192° and decentration increased by a mean of 0.014 mm at the vertical meridian at 2 years postoperatively (P = 0.37 and P = 0.27, respectively), meanwhile, tilt increased by 0.265° and decentration increased by 0.012 mm at the horizontal meridian (P = 0.11 and P = 0.22, respectively). CONCLUSIONS: The follow-up results suggest the tilt and decentration of multifocal IOL implantation with optic capture in Berger space remain stable in an acceptable range within 2 years after cataract surgery in children above the age of 5. TRIAL REGISTRATION: The study was approved by the Ethics Committee of Qingdao Eye Hospital, and registered on Chinese Clinical Trial Registry (ChiCTR identifier: 1900023155).


Assuntos
Extração de Catarata , Catarata , Lentes Intraoculares Multifocais , Acuidade Visual , Humanos , Masculino , Feminino , Estudos Prospectivos , Catarata/complicações , Catarata/fisiopatologia , Pré-Escolar , Criança , Extração de Catarata/métodos , Extração de Catarata/efeitos adversos , Seguimentos , Desenho de Prótese , Migração do Implante de Lente Intraocular/diagnóstico , Migração do Implante de Lente Intraocular/fisiopatologia , Migração do Implante de Lente Intraocular/etiologia , Migração do Implante de Lente Intraocular/cirurgia , Implante de Lente Intraocular/métodos , Lactente
7.
J Transl Med ; 21(1): 70, 2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-36732787

RESUMO

BACKGROUND: Periodontal ligament stem cells (PDLSCs) are important seed cells for tissue engineering to realize the regeneration of alveolar bone. Understanding the gene regulatory mechanisms of osteogenic lineage differentiation in PDLSCs will facilitate PDLSC-based bone regeneration. However, these regulatory molecular signals have not been clarified. METHODS: To screen potential regulators of osteogenic differentiation, the gene expression profiles of undifferentiated and osteodifferentiated PDLSCs were compared by microarray and bioinformatics methods, and PSAT1 was speculated to be involved in the gene regulation network of osteogenesis in PDLSCs. Lentiviral vectors were used to overexpress or knock down PSAT1 in PDLSCs, and then the proliferation activity, migration ability, and osteogenic differentiation ability of PDLSCs in vitro were analysed. A rat mandibular defect model was built to analyse the regulatory effects of PSAT1 on PDLSC-mediated bone regeneration in vivo. The regulation of PSAT1 on the Akt/GSK3ß/ß-catenin signalling axis was analysed using the Akt phosphorylation inhibitor Ly294002 or agonist SC79. The potential sites on the promoter of PSAT1 that could bind to the transcription factor ATF4 were predicted and verified. RESULTS: The microarray assay showed that the expression levels of 499 genes in PDLSCs were altered significantly after osteogenic induction. Among these genes, the transcription level of PSAT1 in osteodifferentiated PDLSCs was much lower than that in undifferentiated PDLSCs. Overexpressing PSAT1 not only enhanced the proliferation and osteogenic differentiation abilities of PDLSCs in vitro, but also promoted PDLSC-based alveolar bone regeneration in vivo, while knocking down PSAT1 had the opposite effects in PDLSCs. Mechanistic experiments suggested that PSAT1 regulated the osteogenic lineage fate of PDLSCs through the Akt/GSK3ß/ß-catenin signalling axis. PSAT1 expression in PDLSCs during osteogenic differentiation was controlled by transcription factor ATF4, which is realized by the combination of ATF4 and the PSAT1 promoter. CONCLUSION: PSAT1 is a potential important regulator of the osteogenic lineage differentiation of PDLSCs through the ATF4/PSAT1/Akt/GSK3ß/ß-catenin signalling pathway. PSAT1 could be a candidate gene modification target for enhancing PDLSCs-based bone regeneration.


Assuntos
Osteogênese , Ligamento Periodontal , Animais , Ratos , Fator 4 Ativador da Transcrição/metabolismo , Fator 4 Ativador da Transcrição/farmacologia , beta Catenina/metabolismo , Diferenciação Celular/genética , Proliferação de Células , Células Cultivadas , Glicogênio Sintase Quinase 3 beta/metabolismo , Osteogênese/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células-Tronco , Fatores de Transcrição/metabolismo , Transaminases/metabolismo
8.
Opt Lett ; 48(21): 5711-5714, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37910740

RESUMO

Monitoring microvascular structure and function is of great significance for the diagnosis of many diseases. In this study, we demonstrate the feasibility of OR-PAM to nailbed microcirculation detection as a new, to the best of our knowledge, application scenario in humans. We propose a dual-wavelength optical-resolution photoacoustic microscopy (OR-PAM) with improved local-flexible coupling to image human nailbed microvasculature. Microchip lasers with 532 nm wavelength are employed as the pump sources. The 558 nm laser is generated from the 532 nm laser through the stimulated Raman scattering effect. The flowing water, circulated by a peristaltic pump, maintains the acoustic coupling between the ultrasonic transducer and the sample. These designs improve the sensitivity, practicality, and stability of the OR-PAM system for human in vivo experiments. The imaging of the mouse ear demonstrates the ability of our system to acquire structural and functional information. Then, the system is applied to image human nailbed microvasculature. The imaging results reveal that the superficial capillaries are arranged in a straight sagittal pattern, approximately parallel to the long axis of the finger. The arterial and venular limbs are distinguished according to their oxygen saturation differences. Additionally, the images successfully discover the capillary loops with single or multiple twists, the oxygen release at the end of the capillary loop, and the changes when the nailbed is abnormal.


Assuntos
Microscopia , Técnicas Fotoacústicas , Animais , Camundongos , Humanos , Microscopia/métodos , Microvasos/diagnóstico por imagem , Lasers , Capilares , Análise Espectral , Técnicas Fotoacústicas/métodos
9.
J Environ Manage ; 344: 118570, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37459810

RESUMO

Economical and easily prepared bulking agents and microbial carriers are essential in the practical application of bioevaporation process. Biofilm-developed biomass residues not only provide structural support and microbial sources but also may contribute metabolic heat to the bioevaporation process, achieving the enhanced water evaporation and synergistic treatment of biomass residues. In this study, biofilm was cultivated on the rice straw, wheat straw, sawdust, corncob, luffa cylindrica and palm first, then those biofilm-developed biomass residues were successfully used as the bulking agents and microbial carriers in food waste bioevaporation. The degradation potential (volatile solid degradation ratio) of those biomass residues was in the order of corncob (23.96%), wheat straw (21.12%), rice straw (14.57%), luffa cylindrica (11.02%), sawdust (-2.87%) and palm (-9.24%). It's primarily the degradation of the major components, cellulose and hemicellulose, in corncob and wheat straw governed the metabolic heat contribution (91.73 and 79.61%) to the bioevaporation process. While the high lignin content in sawdust (14.57%) and palm (28.62%) caused negligible degradation of cellulose and hemicellulose, hence made them only function as structural supporter and did not contribute any metabolic heat. Moreover, though the metabolic heat contribution of rice straw and luffa cylindrica reached 58.19 and 37.84%, their lowest lignocellulose content (62.99 and 65.95%) and their lower density, as well as the dominated Xanthomonas (bacteria) and Mycothermus (fungi) led to their rapid collapse during the repeated cycles of bioevaporation. The greatest abundance of thermophilic bacteria (22.3-88.0%) and thermophilic fungi (82.0-99.3%) was observed in the corncob pile. Furthermore, considering the Staphylococcus (pathogenic bacteria) and Candida (animal pathogen) was effectively inhibited, the biofilm-developed corncob was the most favorable bulking agents and microbial carrier for the synergistic bioevaporation of highly concentrated organic wastewater and biomass residues.


Assuntos
Temperatura Alta , Eliminação de Resíduos , Animais , Alimentos , Biomassa , Lignina/metabolismo , Celulose , Fungos/metabolismo , Bactérias/metabolismo
10.
J Headache Pain ; 24(1): 57, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37217887

RESUMO

BACKGROUND: Although headache disorders are common, the current diagnostic approach is unsatisfactory. Previously, we designed a guideline-based clinical decision support system (CDSS 1.0) for diagnosing headache disorders. However, the system requires doctors to enter electronic information, which may limit widespread use. METHODS: In this study, we developed the updated CDSS 2.0, which handles clinical information acquisition via human-computer conversations conducted on personal mobile devices in an outpatient setting. We tested CDSS 2.0 at headache clinics in 16 hospitals in 14 provinces of China. RESULTS: Of the 653 patients recruited, 18.68% (122/652) were suspected by specialists to have secondary headaches. According to "red-flag" responses, all these participants were warned of potential secondary risks by CDSS 2.0. For the remaining 531 patients, we compared the diagnostic accuracy of assessments made using only electronic data firstly. In Comparison A, the system correctly recognized 115/129 (89.15%) cases of migraine without aura (MO), 32/32 (100%) cases of migraine with aura (MA), 10/10 (100%) cases of chronic migraine (CM), 77/95 (81.05%) cases of probable migraine (PM), 11/11 (100%) cases of infrequent episodic tension-type headache (iETTH), 36/45 (80.00%) cases of frequent episodic tension-type headache (fETTH), 23/25 (92.00%) cases of chronic tension-type headache (CTTH), 53/60 (88.33%) cases of probable tension-type headache (PTTH), 8/9 (88.89%) cases of cluster headache (CH), 5/5 (100%) cases of new daily persistent headache (NDPH), and 28/29 (96.55%) cases of medication overuse headache (MOH). In Comparison B, after combining outpatient medical records, the correct recognition rates of MO (76.03%), MA (96.15%), CM (90%), PM (75.29%), iETTH (88.89%), fETTH (72.73%), CTTH (95.65%), PTTH (79.66%), CH (77.78%), NDPH (80%), and MOH (84.85%) were still satisfactory. A patient satisfaction survey indicated that the conversational questionnaire was very well accepted, with high levels of satisfaction reported by 852 patients. CONCLUSIONS: The CDSS 2.0 achieved high diagnostic accuracy for most primary and some secondary headaches. Human-computer conversation data were well integrated into the diagnostic process, and the system was well accepted by patients. The follow-up process and doctor-client interactions will be future areas of research for the development of CDSS for headaches.


Assuntos
Cefaleia Histamínica , Sistemas de Apoio a Decisões Clínicas , Transtornos da Cefaleia Secundários , Transtornos da Cefaleia , Transtornos de Enxaqueca , Enxaqueca com Aura , Cefaleia do Tipo Tensional , Humanos , Cefaleia do Tipo Tensional/diagnóstico , Transtornos da Cefaleia/diagnóstico , Cefaleia/diagnóstico , Transtornos de Enxaqueca/diagnóstico , Computadores
11.
Int Ophthalmol ; 43(12): 4621-4629, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37715824

RESUMO

PURPOSE: To assess the visual quality after implantation of a rotationally asymmetric multifocal intraocular lens (IOL) using a new method according to the angle kappa. SETTING: Qingdao Eye Hospital, Qingdao, China. DESIGN: Prospective case series. METHODS: Patients with the implantation of SBL-3 IOLs for age-related cataract from September to December 2019 had the distance-horizontal zone of the IOL placed at the center of the optic axis using the Callisto Eye System. Postoperative visual acuities and defocus curves were recorded. Modulation transfer function cutoff frequency, Strehl ratio, and objective scatter index were measured using the Optical Quality Analysis System. The decentration and tilt of IOLs were analyzed by iTrace aberrometry and anterior segment optical coherence tomography. A questionnaire of patient satisfaction was also collected. RESULTS: Thirty patients (60 eyes) were involved, with a balanced sex ratio. Their average age was 56.04 ± 10.83 years. The average angle kappa distance was 0.23 ± 0.121 mm. At 3 months after surgery, the mean uncorrected and corrected distance visual acuities were 0.01 ± 0.07 logMAR and 0.01 ± 0.06 logMAR. The uncorrected intermediate and near visual acuities were 0.09 ± 0.11 logMAR and 0.09 ± 0.11 logMAR. The mean horizontal and vertical tilts of IOLs were 0.67 ± 0.52 degrees and 0.47 ± 0.32 degrees. The mean decentration of IOLs was 0.17 ± 0.08 mm. Most patients were satisfied with their distance, intermediate, and near vision. There was mild glare in 58.3% of the eyes. CONCLUSIONS: Locating the center of the optic axis in the distance-horizontal zone during the implantation of SBL-3 IOLs could provide satisfactory visual acuity and quality.


Assuntos
Lentes Intraoculares , Lentes Intraoculares Multifocais , Facoemulsificação , Humanos , Pessoa de Meia-Idade , Idoso , Implante de Lente Intraocular/métodos , Acuidade Visual , Satisfação do Paciente , Desenho de Prótese , Pseudofacia
12.
Opt Lett ; 47(14): 3515-3518, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35838717

RESUMO

An acoustic coupling scheme largely determines the performance of optical-resolution photoacoustic microscopy (OR-PAM), including practicability, sensitivity, and stability. In this study, we propose OR-PAM based on a local-flexible acoustic coupling scheme, which includes a well-designed combiner connecting a set of circulating systems. The combiner integrates an objective lens and an ultrasonic transducer, controls the water level, restricts the flow rate, and drains bubbles. The circulating system provides sustained and steady flowing water. The flowing water constrained in the combiner and the circulating system forms a flexible and stable local contact between the sample and the transducer. Phantom experiments demonstrate that the proposed method can maintain high optical resolution but improve the detection sensitivity by approximately 1.9 times in comparison to dry coupling. In vivo imaging experiments of the mouse eyeground are conducted to examine the practicability of the proposed system in biomedicine. Moreover, in vivo experiments show that OR-PAM based on local-flexible coupling can reveal more details of eyeground microvasculatures, benefiting from its enhanced sensitivity. These merits promise that OR-PAM based on local-flexible coupling may have broad applications in biomedical fields.


Assuntos
Lentes , Técnicas Fotoacústicas , Animais , Camundongos , Microscopia/métodos , Técnicas Fotoacústicas/métodos , Análise Espectral , Água
13.
Langmuir ; 38(15): 4774-4784, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35380846

RESUMO

Water-soluble amphiphilic polymers are vital chemicals in the oil and gas industry to retard crystal growth of hydrocarbon hydrate via surface adsorption and suppress nucleation of a pristine hydrate nucleus, thereby preventing formation of hydrate blockages in flow lines during oil and natural gas production. Apart from a few theoretical modeling studies, an experimental method to study the polymer/water interface in the crystal growth is critically needed. Here, water motions in the hydration shells of an exemplary kinetic inhibitor, poly(N-vinylcaprolactam), during hydrate formation from the tetrahydrofuran/water system are revealed via nuclear magnetic resonance relaxometry. Unequivocal experiments show that the pivotal interfacial water in the tightly bound state gradually freezes at rates depending on the polymer molecular weight (MW). This is supported by nonfreezable water analysis, which is correlated to the inhibition time. The polymers tune the kinetics of the hydration process via interaction with and perturbation of the water molecules. The free water component in the polymer solution crystallizes at a very slow rate when in partially restricted mobility, whereas the bound water component increases in the reaction, with the polymer/water interface serving as the reaction sites. The appropriate MW (including average MW and polydispersity values) of the inhibitive polymers can give rise to maximal retardation of the hydrate crystal growth. This work will help control other multiphase crystallization kinetic processes through the design of inhibitors or promoters functioning in the interface.


Assuntos
Polímeros , Água , Caprolactama/análogos & derivados , Cinética , Espectroscopia de Ressonância Magnética , Água/química
14.
Sensors (Basel) ; 22(11)2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35684735

RESUMO

Given the lack of scale information of the image features detected by the visual SLAM (simultaneous localization and mapping) algorithm, the accumulation of many features lacking depth information will cause scale blur, which will lead to degradation and tracking failure. In this paper, we introduce the lidar point cloud to provide additional depth information for the image features in estimating ego-motion to assist visual SLAM. To enhance the stability of the pose estimation, the front-end of visual SLAM based on nonlinear optimization is improved. The pole error is introduced in the pose estimation between frames, and the residuals are calculated according to whether the feature points have depth information. The residuals of features reconstruct the objective function and iteratively solve the robot's pose. A keyframe-based method is used to optimize the pose locally in reducing the complexity of the optimization problem. The experimental results show that the improved algorithm achieves better results in the KITTI dataset and outdoor scenes. Compared with the pure visual SLAM algorithm, the trajectory error of the mobile robot is reduced by 52.7%. The LV-SLAM algorithm proposed in this paper has good adaptability and robust stability in different environments.

15.
Nano Lett ; 21(19): 8111-8118, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34597054

RESUMO

Despite being promising, the clinical application of magnetic hyperthermia for brain cancer treatment is limited by the requirement of highly invasive intracranial injections. To overcome this limitation, here we report the development of gallic acid-coated magnetic nanoclovers (GA-MNCs), which allow not only for noninvasive delivery of magnetic hyperthermia but also for targeted delivery of systemic chemotherapy to brain tumors. GA-MNCs are composed of clover-shaped MNCs in the core, which can induce magnetic heat in high efficiency, and polymerized GA on the shell, which enables tumor vessel-targeting. We demonstrate that intravenous administration of GA-MNCs following alternating magnetic field exposure effectively inhibited brain cancer development and preferentially disrupted tumor vasculature, making it possible to efficiently deliver systemic chemotherapy for further improved efficacy. Due to the noninvasive nature and high efficiency in killing tumor cells and enhancing systemic drug delivery, GA-MNCs have the potential to be translated for improved treatment of brain cancer.


Assuntos
Neoplasias Encefálicas , Hipertermia Induzida , Nanopartículas de Magnetita , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Humanos , Hipertermia , Fenômenos Magnéticos
16.
Int J Mol Sci ; 23(22)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36430269

RESUMO

Intermittent fasting confers protections to various diseases including autoimmune disorders, but the specific effects of intermittent fasting on Sjögren's syndrome (SS) remains inconclusive. The present study was undertaken to determine the specific impact of alternate-day fasting (ADF) on newly established SS-like sialadenitis using non-obese diabetic (NOD) mice. Female NOD mice were deprived of food every other day from 10 to 13 weeks of age, the early stage of established SS, and then analyzed for the disease characteristics. Mice in the ADF group had higher salivary flow rate and attenuated submandibular gland (SMG) inflammation, compared to the control mice fed with standard chow ad libitum. The improvements were accompanied with a decrease in the total leukocytes, T and B lymphocytes and activated CD4 and CD8 T cells, and a down-regulation of pro-inflammatory cytokines IFN-γ and IL-17, chemokine receptor CXCR3 and its ligands CXCL9 and CXCL11 in the SMGs. ADF also led to elevated mRNA levels of water channel protein aquaporin 5 and tight junction protein claudin-1, two factors crucial for normal salivary secretion in the SMGs. In addition, ADF reduced the proportion of IFN-γ- and IL-17- expressing CD4 T cells and diminished mRNA levels of IFN-γ, TNF-α, and IL-17 in the total submandibular draining lymph node cells. Taken together, ADF is effective in ameliorating newly established SS-associated salivary gland exocrinopathy in NOD mice.


Assuntos
Diabetes Mellitus Experimental , Sialadenite , Síndrome de Sjogren , Feminino , Camundongos , Animais , Camundongos Endogâmicos NOD , Interleucina-17/genética , Jejum , Sialadenite/patologia , RNA Mensageiro
17.
Int J Mol Sci ; 23(12)2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35743279

RESUMO

Ferritin possesses an immune function to defend against pathogen infection. To elucidate the immunity-protecting roles of ferritin from Ctenopharyngodon idellus (Ciferritin) against virus infection, the cDNA and promoter sequences of Ciferritin were determined, and the correlations between Ciferrtin expressions and promoter methylation levels were analyzed. In addition, the functional role of Ciferrtin on GCRV (grass carp reovirus) infection was assessed. The full-length cDNA of Ciferritin is 1053 bp, consists of a 531 bp open-reading frame, and encodes 176 amino acids. Ciferritin showed the highest sequence identity with the ferritin middle subunit of Mylopharyngodon piceus (93.56%), followed by the subunits of Megalobrama amblycephala and Sinocyclocheilus rhinocerous. Ciferritin contains a conserved ferritin domain (interval: 10−94 aa), and the caspase recruitment domain (CARD) and Rubrerythrin domain were also predicted. In the spleen and kidney, significantly higher Ciferritin expressions were observed at 6, 12, 24, or 168 h post GCRV infection than those in the PBS injection group (p < 0.05). The Ciferrtin expression level in the progeny of maternal-immunized grass carp was significantly higher than that in the progeny of common grass carp (p < 0.05). Ciferritin promoter methylation level in the progeny from common grass carp was 1.27 ± 0.15, and in the progeny of the maternal-immunized group was 1.00 ± 0.14. In addition, methylation levels of "CpG9" and "CpG10" loci were significantly lower in the progeny of maternal-immunized fish than those in the common group. Except for the "CpG5", methylation levels of all other detected "CpG" loci negatively correlated with Ciferritin expression levels. Furthermore, the total methylation level of "CpG1−10" negatively correlated with the Ciferritin expressions. The Ciferritin expression level was significantly up-regulated, and the VP7 protein levels were significantly reduced, at 24 h post GCRV infection in the Ciferritin over-expression cells (p < 0.05). The results from the present study provide sequence, epigenetic modification and expression, and anti-GCRV functional information of Ciferritin, which provide a basis for achieving resistance to GCRV in grass carp breeding.


Assuntos
Carpas , Doenças dos Peixes , Infecções por Reoviridae , Reoviridae , Sequência de Aminoácidos , Animais , Carpas/genética , Carpas/metabolismo , DNA Complementar/genética , Ferritinas/genética , Ferritinas/metabolismo , Proteínas de Peixes/metabolismo , Filogenia , Reoviridae/genética , Infecções por Reoviridae/genética , Infecções por Reoviridae/veterinária
18.
Int Ophthalmol ; 42(8): 2459-2472, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35192105

RESUMO

PURPOSE: This study evaluated the clinical safety and efficacy of tanfanercept (HBM9036) ophthalmic solution as a novel treatment for dry eye disease (DED) in a controlled adverse environment (CAE) study conducted in China. METHODS: In a single-center, double-masked, randomized, placebo-controlled study, 100 patients received 0.25% tanfanercept, or placebo, twice daily for eight weeks. A mobile international CAE® DE Model was used for patient selection with a standardized challenge endpoint. Primary efficacy endpoint was fluorescein inferior corneal staining score (ICSS) pre- to post-CAE challenge from baseline. Secondary endpoints included Schirmer's Tear Test, Tear-Film Break-Up Time, Ocular Discomfort Score, Ora Calibra® Ocular Discomfort and 4-Symptom Questionnaire, total corneal staining score (TCSS), and drop comfort. Signs and symptoms were assessed both pre- and post-CAE to evaluate the efficacy of tanfanercept on both environmental and CAE endpoints. RESULTS: The tanfanercept treatment group showed improvement in ICSS pre- to post-CAE change from baseline scores when compared to placebo (- 0.61 ± 0.11 and - 0.54 ± 0.11, respectively; mean difference = 0.07, p = 0.65). TCSS pre-post-CAE change from baseline scores was also in favor of active when compared to placebo (- 1.03 ± 0.21 and - 0.67 ± 0.21, respectively; mean difference = 0.37, p = 0.23). Schirmer's score improvement was demonstrated in favor of active (1.87 ± 0.62 mm) as compared to placebo (1.28 ± 0.62 mm; mean difference = 0.59 mm, p = 0.50). Change from baseline in mean Tear-Film Break-up Time favored active treatment over placebo (mean difference = 1.21 s, p = 0.45). Notably, the tanfanercept showed more obvious benefits for each DED sign in a subgroup of subjects ≥ 35 years of age. Tanfanercept was well tolerated with no serious adverse events occurring during the study. CONCLUSION: Tanfanercept demonstrated improvements in favor of active as compared to placebo in the signs of DED, being safe and well tolerated. These data support further evaluation of tanfanercept for the treatment of DED in China. TRIAL REGISTRATION: This study was retrospectively registered at ClinicalTrials.gov (NCT04092907) on September 17, 2019.


Assuntos
Síndromes do Olho Seco , Fator de Necrose Tumoral alfa , Método Duplo-Cego , Síndromes do Olho Seco/diagnóstico , Síndromes do Olho Seco/tratamento farmacológico , Fluoresceína , Humanos , Imunossupressores/uso terapêutico , Soluções Oftálmicas/uso terapêutico , Lágrimas , Resultado do Tratamento , Inibidores do Fator de Necrose Tumoral
19.
J Cell Mol Med ; 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34028189

RESUMO

Both human periodontal ligament stem cells (hPDLSCs) and human gingival mesenchymal stem cells (hGMSCs) are candidate seed cells for bone tissue engineering, but the osteo-differentiation ability of the latter is weaker than the former, and the mechanisms are unknown. To explore the potential regulation of mRNAs and long non-coding RNAs (lncRNAs), this study obtained the gene expression profiles of hPDLSCs and hGMSCs in both undifferentiated and osteo-differentiated conditions by microarray assay and then analysed the common and specific differentially expressed mRNAs and lncRNAs in hPDLSCs and hGMSCs through bioinformatics method. The results showed that 275 mRNAs and 126 lncRNAs displayed similar changing patterns in hPDLSCs and hGMSCs after osteogenic induction, which may regulate the osteo-differentiation in both types of cells. In addition, the expression of 223 mRNAs and 238 lncRNAs altered only in hPDLSCs after osteogenic induction, and 177 mRNAs and 170 lncRNAs changed only in hGMSCs. These cell-specific differentially expressed mRNAs and lncRNAs could underlie the different osteo-differentiation potentials of hPDLSCs and hGMSCs. Finally, dickkopf Wnt signalling pathway inhibitor 1 (DKK1) was proved to be one regulator for the weaker osteo-differentiation ability of hGMSCs through validation experiments. We hope these results help to reveal new mRNAs-lncRNAs-based molecular mechanism for osteo-differentiation of hPDLSCs and hGMSCs and provide clues on strategies for improving stem cell-mediated bone regeneration.

20.
Nutr Metab Cardiovasc Dis ; 31(1): 333-343, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33500109

RESUMO

BACKGROUND AND AIMS: Diabetes is one of the most important risk factors and comorbidities of ischemic stroke. Endoplasmic reticulum stress (ERS) is considered to be the major injury mechanism of ischemic stroke with diabetes. Studies have found that incretin can inhibit ERS in ischemia-reperfusion injury of the liver and heart. We aimed to explore the effects of GLP-1/GIP double agonist DA3-CH and GLP-1 single agonist liraglutide on ERS and apoptosis in diabetic rats with cerebral ischemia-reperfusion injury. METHODS AND RESULTS: 72 Sprague-Dawley (SD) male rats were randomly divided into 4 groups: ① blank group (Sham group, n = 18); model group (Saline group, n = 18); DA3 treatment group (DA3 group, n = 18); liraglutide treatment group (Lir group, n = 18). The Sham group was not given any treatment and was only raised in the same environment as the other groups. The remaining 3 groups used STZ-induced diabetes models. After the successful membrane formation of diabetes, DA3-CH and liraglutide (10 mmol/kg, once-daily for 14 days) were injected intraperitoneally. Thereafter, rats were subjected to middle cerebral artery occlusion followed by 24-h reperfusion. Animals were evaluated for neurologic deficit score, infarct volume, and biomarker analyses of the brain after ischemia. The DA3-CH-treated and liraglutide-treated groups showed significantly reduced scores of neurological dysfunction and cerebral infarction size, and reduced the expression of ERS markers GRP78, CHOP and Caspase-12, and the expression of apoptosis marker bax. Anti-apoptotic markers bcl-2 and neuronal numbers increased significantly. CONCLUSIONS: DA3-CH and liraglutide have obvious neuroprotective effects in a rat model of cerebral ischemia-reperfusion injury with diabetes, which can reduce the infarct size and the neurological deficit score. Their exert neuroprotective effects in a rat model of cerebral ischemia-reperfusion injury with diabetes by inhibiting endoplasmic reticulum stress and thereby reducing apoptosis. DA3 is better than liraglutide.


Assuntos
Encéfalo/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Incretinas/farmacologia , Infarto da Artéria Cerebral Média/tratamento farmacológico , Liraglutida/farmacologia , Peptídeos/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Chaperona BiP do Retículo Endoplasmático , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Humanos , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/patologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Ratos Sprague-Dawley , Receptores dos Hormônios Gastrointestinais/agonistas , Receptores dos Hormônios Gastrointestinais/metabolismo , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Transdução de Sinais , Estreptozocina
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