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1.
J Burn Care Res ; 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34520555

RESUMO

The goal of this study was to determine what effect obese body weight and a burn injury can have on the metabolism of glucose and lipids in rats. We used a 3*3 factorial model design to provide basic glucose and lipid metabolic data characterizing the interaction between different weight and burn injury groups. Two hundred Sprague Dawley (SD) rats were categorized into three weight groups (normal, overweight, obese) and then further divided into control, second degree, and third degree burn groups. Our model compared interactions between weight and burn injury factors according to the above groups. Blood glucose and lipid metabolism indicators were monitored on the 1st, 3rd, 7th and 14th days after burn injury occurred, and burned skin and blood samples were collected for testing. Compared with the normal weight group, the overweight group's fast blood glucose (FBG), fast insulin (FINS) and homeostasis model assessment of insulin resistance (HOMA-IR) were higher (P<0.05), and FBG in the obese group was higher than the normal weight group (P<0.05).Burn injuries combined with obese body weight had an interactive effect on FBG, FINS and HOMA-IR after burn injury (P<0.05). Burn injury combined with obese body weight had an interaction on low density lipoprotein cholesterol (LDL-C) on the 3rd day after burn injury (P<0.05). Burn injury combined with obese weight had no interaction on triglyceride (TRG), total cholesterol (TC) and high density lipoprotein cholesterol (HDL-C) (P>0.05).Rats in the overweight and obese weight groups were observed to develop an adaptation and tolerance to a higher metabolic rate after burn injuries occurred.

2.
Acta Biomater ; 2021 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-34520884

RESUMO

The major limitation of traditional local anesthetics is the finite duration of a single injection. The present study developed two kinds of novel injectable anesthetic nanocomposites based on mesoporous silica, and evaluated their long-lasting analgesic effect and biosafety. The nanoparticulate carriers, mesoporous silica nanoparticles (MSNs) and mesoporous silica-coated gold nanorods (GNR@MSN), were firstly constructed using the oil-water biphase reaction approach and then ropivacaine (RPC), a local anesthetic, was loaded into the mesoporous carriers by vacuum suction. Transmission electron microscopic images showed the well-ordered mesoporous structure for drug loading. RPC-loaded MSNs and RPC-loaded GNR@MSN exhibited a sustained-release pattern in vitro, and the latter also showed a controlled-release manner triggered by near-infrared (NIR) irradiation. RPC-loaded MSNs and RPC-loaded GNR@MSN caused an initial sensory blockade in mice that lasted for 6 hours, almost 2.5 folds of that from free RPC solution. Furthermore, upon NIR irradiation, the latter induced three additional periods of the blockade. Neither of them showed motor nerve block, which may be due to the sustained release manner. The low myotoxicity and low neurotoxicity of the two nanocomposites were presented both in vitro and in vivo. These results demonstrate the potential of the mesoporous silica-based analgesic nanocomposites in effectively controlling postoperative pain, maybe RPC-loaded MSNs for moderate pain and RPC-loaded GNR@MSN for severe pain. STATEMENT OF SIGNIFICANCE: Adequate postoperative analgesia helps early functional exercise after surgery and accelerates rapid recovery, while uncontrolled postoperative pain probably develops chronic post-surgical pain that impacts the life quality of patients for a long time. However, postoperative pain management is still a challenge. The current treatment drugs are always accompanied by some side effects due to their systemic effect. Opioids have risks of addiction and respiratory depression, and nonsteroidal anti-inflammatory drugs can lead to gastrointestinal reaction. Therefore, the long-lasting local anesthetic formulation with good biocompatibility is the most promising solution to manage post-surgical pain. The present study developed novel injectable anesthetic nanocomposites based on mesoporous silica, providing long-lasting pain relief in mice with minimal toxicity.

3.
Sheng Wu Gong Cheng Xue Bao ; 37(8): 2703-2718, 2021 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-34472290

RESUMO

Plants with alien genomic components (alien chromosomes / chromosomal fragments / genes) are important materials for genomic research and crop improvement. To date, four strategies based on trait observation, chromosome analysis, specific proteins, and DNA sequences have been developed for the identification of alien genomic components. Among them, DNA sequence-based molecular markers are mainly used to identify alien genomic components. This review summarized several molecular markers for identification of alien genomic components in wheat, cabbage and other important crops. We also compared the characteristics of nine common molecular markers, such as simple sequence repeat (SSR), insertion-deletion (InDel) and single nucleotide polymorphism (SNP). In general, the accuracy of using a combination of different identification methods is higher than using a single identification method. We analyzed the application of different combination of identification methods, and provided the best combination for wheat, brassica and other crops. High-throughput detection can be easily achieved by using the new generation molecular markers such as InDel and SNP, which can be used to determine the precise localization of alien introgression genes. To increase the identification efficiency, other new identification methods, such as microarray comparative genomic hybridization (array-CGH) and suppression subtractive hybridization (SSH), may also be included.


Assuntos
Cromossomos de Plantas , Genoma de Planta , Hibridização Genômica Comparativa , Genoma de Planta/genética , Genômica , Triticum/genética
4.
Plant Methods ; 17(1): 93, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34479588

RESUMO

BACKGROUND: Ploidy manipulation is effective in seedless loquat breeding, in which flesh color is a key agronomic and economic trait. Few techniques are currently available for detecting the genotypes of polyploids in plants, but this ability is essential for most genetic research and molecular breeding. RESULTS: We developed a system for genotyping by quantitative PCR (qPCR) that allowed flesh color genotyping in multiple tetraploid and triploid loquat varieties (lines). The analysis of 13 different ratios of DNA mixtures between two homozygous diploids (AA and aa) showed that the proportion of allele A has a high correlation (R2 = 0.9992) with parameter b [b = a1/(a1 + a2)], which is derived from the two normalized allele signals (a1 and a2) provided by qPCR. Cluster analysis and variance analysis from simulating triploid and tetraploid hybrids provided completely correct allelic configurations. Four genotypes (AAA, AAa, Aaa, aaa) were found in triploid loquats, and four (AAAA, AAAa, AAaa, Aaaa; absence of aaaa homozygotes) were found in tetraploid loquats. DNA markers analysis showed that the segregation of flesh color in all F1 hybrids conformed to Mendel's law. When tetraploid B431 was the female parent, more white-fleshed triploids occurred among the progeny. CONCLUSIONS: qPCR can detect the flesh color genotypes of loquat polyploids and provides an alternative method for analyzing polyploid genotype and breeding, dose effects and allele-specific expression.

5.
Nanoscale ; 13(29): 12553-12564, 2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34477614

RESUMO

Chemodynamic therapy (CDT), the ability to transform H2O2 into a highly toxic hydroxyl radical (˙OH) through a Fenton or Fenton like reaction to kill cancer cells, enables selective tumor therapy. However, the effect is seriously limited by the insufficiency of endogenous H2O2 in cancer cells. Additionally, the specific recognition of epitope imprinting plays an important role in targeting cancer cell markers. In this work, we prepared H2O2 self-supplying degradable epitope molecularly imprinted polymers (MIP) for effective CDT, employing fluorescent calcium peroxide (FCaO2) as an imaging probe and a source of H2O2, the exposed peptide in the CD47 extracellular region as the template, copper acrylate as one of the functional monomers and N,N'-bisacrylylcystamine (BAC) as a cross-linker. MIP with recognition sites can specifically target CD47-positive cancer cells to achieve fluorescence imaging. Under the reduction of glutathione (GSH), the MIP were degraded and the exposed FCaO2 reacted with water to continuously produce H2O2 in the slightly acidic environment in cancer cells. The self-supplied H2O2 produced ˙OH through a Fenton like catalytic reaction mediated by copper ions in the MIP framework, inducing cancer cell apoptosis. Therefore, the MIP nano-platform, which was capable of specific recognition of the cancer cell marker, H2O2 self-supply and controlled treatment, was successfully used for targeted CDT.


Assuntos
Peróxido de Hidrogênio , Polímeros , Linhagem Celular Tumoral , Epitopos , Imagem Óptica
6.
Exp Cell Res ; 407(2): 112800, 2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34487731

RESUMO

PURPOSE: Increased permeability of retinal capillary endothelial cells is a key feature in the progression of diabetic retinopathy (DR). Precisely why and how diabetes causes dysfunction in retinal capillary endothelial cells is not well understood, making it challenging to explore more advanced therapeutics. METHODS: Cell proliferation was assessed by the Cell Counting Kit-8 assay. Ferroptosis was evaluated by measuring lipid reactive oxygen species levels by flow cytometry and determining malondialdehyde, superoxide dismutase, and glutathione peroxidase levels through biochemical assays. Western blot analysis and quantitative PCR were respectively used to check the expression of proteins and RNAs. Co-immunoprecipitation assays were used to confirm the interaction between TRIM46 and GPX4. RESULTS: High glucose (HG, 25 mM glucose) significantly suppressed cell growth, which could be reversed by the ferroptosis inhibitor, ferrostatin-1. HG treatment time-dependently induced ferroptosis in human retinal capillary endothelial cells (HRCECs) and induced TRIM46 expression. Lentiviral-mediated overexpression of TRIM46 decreased cell resistance against HG-induced ferroptosis, whereas knockdown showed the opposite effect. Administration of RSL3, a ferroptosis agonist, was able to reverse the protective effects of TRIM46 silencing. TRIM46 interacted with GPX4, an important enzyme that suppresses ferroptosis, and promoted GPX4 ubiquitination. Furthermore, lentiviral-mediated overexpression ofGPX4 ameliorated the effects of TRIM46 overexpression and conferred protection to cells against HG-induced ferroptosis. CONCLUSION: TRIM46 and GPX4 form a regulatory pathway that controls HG-induced ferroptosis of HRCECs. Inhibiting this pathway or sustaining the expression of GPX4 enables cells to resist damage caused by HG. We provide new mechanistic insight into the pathology of DR and identified TRIM46 and GPX4 as two molecular targets for the development of effective drugs for DR treatment.

7.
Artigo em Inglês | MEDLINE | ID: mdl-34473468

RESUMO

Single-crystalline LiNi0.6Co0.2Mn0.2O2 cathodes have received great attention due to their high discharge capacity and better electrochemical performance. However, the single-crystal materials are suffering from severe lattice distortion and electrode/electrolyte interface side reactions when cycling at high voltage. Herein, a unique single-crystal LiNi0.6Co0.2Mn0.2O2 with Al and Zr doping in the bulk and a self-formed coating layer of Li2ZrO3 in the surface has been constructed by a facile strategy. The optimized cathode material exhibits excellent structural stability and cycling performance at room/elevated temperatures after long-term cycling. Specifically, even after 100 cycles (1C, 3.0-4.4 V) at 50 °C, the capacity retention for the Al and Zr co-doped sample reaches 92.1%, which is much higher than those of the single Al-doped (85.4%), single Zr-doped (87.1%), and bare samples (76.3%). The characterization results and first-principles calculations reveal that the excellent electrochemical properties are attributed to the stable structure and interface, in which the Al and Zr co-doping hinders cation mixing and suppresses detrimental phase transformations to reduce internal stress and mitigate microcracks, and the coating layer of Li2ZrO3 can protect the surface and suppress interfacial parasitic reactions. Overall, this work provides important insights into how to simultaneously build a stable bulk structure and interface for the single-crystal NCM cathode via a facile preparation process.

8.
Transfusion ; 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34469028

RESUMO

BACKGROUND: Early treatment has a positive effect on autoimmune encephalitis. However, different treatments have individual differences and corresponding contraindications in the clinical. Few reports have described the application of immunoadsorption with Staphylococcal Protein A Column (SPA-IA) in neuroimmune diseases. We aimed to observe the safety and efficiency of SPA-IA in autoimmune encephalitis. PATIENTS AND METHODS: We retrospectively analyzed three cases of autoimmune encephalitis wherein the first-line treatment was ineffective or contraindicated. The clinical features and prognosis during and after SPA-IA are described in detail. RESULTS: All patients were definitely diagnosed with autoimmune encephalitis. After treated with SPA-IA, all antibody titers, except for the serum antibody titer in Patient 2, were markedly decreased in both the cerebral spinal fluid and serum. The mean fibrinogen levels before and after SPA-IA were stable, and there were no clinical bleeding events. The modified Rankin Scale scores and their symptoms improved significantly after the last SPA-IA session or 3 months later. CONCLUSIONS: SPA-IA may be a viable, efficacious, and safe treatment alternative for autoimmune encephalitis with contraindications to traditional treatment or poor response.

9.
J Agric Food Chem ; 69(35): 10371-10378, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34436884

RESUMO

Herein, we combine the exonuclease III (Exo III)-catalyzed release of a Zn2+-dependent ligation DNAzyme with the DNAzyme-driven strand displacement reaction (SDR) to develop a novel homogeneous colorimetric bioassay method for kanamycin (Kana) antibiotic detection. Upon the biorecognition reaction between Kana and a designed hairpin DNA, the DNAzyme-containing strand can be catalytically released by Exo III. Then, this DNAzyme will catalyze the ligation of two oligonucleotides to cause a SDR and the aggregation of gold nanoparticles (Au NPs) labeled by two linker DNA strands. Due to the aggregation of Au NPs for colorimetric signal transduction and the Exo III and SDR-assisted dual signal amplification, this method shows a wide linear range of 5 orders of magnitude and a very low detection limit down to 8.1 fg mL-1. Together with its excellent selectivity, repeatability, reliability, and convenient manipulation, the proposed method shows a great potential for the food quality monitoring application.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , DNA Catalítico , Nanopartículas Metálicas , Antibacterianos , Bioensaio , Catálise , Exodesoxirribonucleases , Ouro , Canamicina , Limite de Detecção , Reprodutibilidade dos Testes , Zinco
10.
Hum Mol Genet ; 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34415307

RESUMO

Nephronophthisis (NPH) is the most prevalent monogenetic disorder leading to end-stage renal failure (ESRD) in childhood. Mutations in Nphp1, encoding a cilia-localized protein, account for the majority of NPH cases. Despite its identification many years ago, Nphp1 deletions targeting exon 4 or exon 20 have not reproduced the histological features of human NPH in murine models. In this study, we deleted exon 2-20 of Nphp1 by CRISPR/Cas9 gene editing to create a near-total knockout (KO) mouse model (Nphp1del2-20/del2-20). Nphp1del2-20/del2-20 mice faithfully reproduced the renal and extrarenal phenotypes associated with human NPH, including renal cyst development, tubular basement membrane thickening, retinal degeneration and abnormal spermatogenesis. Importantly, Nphp1 re-expression using an adenoviral-associated-virus-9 (AAV9) vector could partially rescue both renal and retinal phenotypes in Nphp1del2-20/del2-20 mice. Our results reported the first relevant Nphp1 mouse model with renal phenotypes for human disease. It will be a valuable model for future studies of Nphp1 function and to develop novel treatments for this common childhood disease.

11.
BMC Plant Biol ; 21(1): 376, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34399701

RESUMO

BACKGROUND: Glycolytic pathway is common in all plant organs, especially in oxygen-deficient tissues. Phosphofructokinase (PFK) is a rate-limiting enzyme in the glycolytic pathway and catalyses the phosphorylation of fructose-6-phosphate to fructose-1,6-bisphosphate. Cassava (M. esculenta) root is a huge storage organ with low amount of oxygen. However, less is known about the functions of PFK from M. esculenta (MePFK). We conducted a systematic analysis of MePFK genes to explore the function of the MePFK gene family under hypoxic stress. RESULTS: We identified 13 MePFK genes and characterised their sequence structure. The phylogenetic tree divided the 13 genes into two groups: nine were MePFKs and four were pyrophosphate-fructose-6-phosphate phosphotransferase (MePFPs). We confirmed by green fluorescent protein fusion protein expression that MePFK03 and MePFPA1 were localised in the chloroplast and cytoplasm, respectively. The expression profiles of the 13 MePFKs detected by quantitative reverse transcription polymerase chain reaction revealed that MePFK02, MePFK03, MePFPA1, MePFPB1 displayed higher expression in leaves, root and flower. The expression of MePFK03, MePFPA1 and MePFPB1 in tuber root increased gradually with plant growth. We confirmed that hypoxia occurred in the cassava root, and the concentration of oxygen was sharply decreasing from the outside to the inside root. The expression of MePFK03, MePFPA1 and MePFPB1 decreased with the decrease in the oxygen concentration in cassava root. Waterlogging stress treatment showed that the transcript level of PPi-dependent MePFP and MeSuSy were up-regulated remarkably and PPi-dependent glycolysis bypass was promoted. CONCLUSION: A systematic survey of phylogenetic relation, molecular characterisation, chromosomal and subcellular localisation and cis-element prediction of MePFKs were performed in cassava. The expression profiles of MePFKs in different development stages, organs and under waterlogging stress showed that MePFPA1 plays an important role during the growth and development of cassava. Combined with the transcriptional level of MeSuSy, we found that pyrophosphate (PPi)-dependent glycolysis bypass was promoted when cassava was under waterlogging stress. The results would provide insights for further studying the function of MePFKs under hypoxic stress.


Assuntos
Genoma de Planta , Manihot/enzimologia , Manihot/genética , Fosfofrutoquinases/genética , Fosfofrutoquinases/metabolismo , Cloroplastos/enzimologia , Mapeamento Cromossômico , Cromossomos de Plantas , Sequência Conservada , Citoplasma/enzimologia , Éxons , Flores/enzimologia , Íntrons , Família Multigênica , Oxigênio/metabolismo , Filogenia , Folhas de Planta/enzimologia , Raízes de Plantas/enzimologia , Regiões Promotoras Genéticas , Estresse Fisiológico/genética , Transcriptoma
13.
Biomed Res Int ; 2021: 9984112, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34337069

RESUMO

Background: Baicalin is an extract from the traditional Chinese herb Scutellaria baicalensis and has the potential to treat osteosarcoma (OS). However, the transcriptome-level mechanism of baicalin-mediated antitumor effects in OS has not yet been investigated. The aim of this study was to analyze the competitive endogenous RNA (ceRNA) regulatory network involved in baicalin-induced apoptosis of OS cells. Methods: In this study, CCK-8 and flow cytometry assays were used to detect the antitumor effects of baicalin on human OS MG63 cells. Furthermore, transcriptome sequencing was employed to establish the long noncoding RNA (lncRNA), microRNA (miRNA), and mRNA profiles. Results: Baicalin inhibited MG63 cell proliferation and induced apoptosis. Totals of 58 lncRNAs, 31 miRNAs, and 2136 mRNAs in the baicalin-treated MG63 cells were identified as differentially expressed RNAs compared to those in control cells. Of these, 2 lncRNAs, 3 miRNAs, and 18 mRNAs were included in the ceRNA regulatory network. The differentially expressed RNAs were confirmed by quantitative real-time PCR (qRT-PCR). Conclusions: By identifying the ceRNA network, our results provide new information about the possible molecular basis of baicalin, which has potential applications in OS treatment.

14.
Artigo em Inglês | MEDLINE | ID: mdl-34378908

RESUMO

The next-generation spintronic devices including memristors, tunneling devices, or stochastic switching exert surging demands on magnetic nanostructures with novel coupling schemes. Taking advantage of a phase decomposition mechanism, a unique Ni-NiO nanocomposite has been demonstrated using a conventional pulsed laser deposition technique. Ni nanodomains are segregated from NiO and exhibit as faceted "emerald-cut" morphologies with tunable dimensions affected by the growth temperature. The sharp interfacial transition between ferromagnetic (002) Ni and antiferromagnetic (002) NiO, as characterized by high-resolution transmission electron microscopy, introduces a strong exchange bias effect and magneto-optical coupling at room temperature. In situ heating-cooling X-ray diffraction (XRD) study confirms an irreversible phase transformation between Ni and NiO under ambient atmosphere. Synthesizing highly functional two-phase nanocomposites with a simple bottom-up self-assembly via such a phase decomposition mechanism presents advantages in terms of epitaxial quality, surface coverage, interfacial coupling, and tunable nanomagnetism, which are valuable for new spintronic device implementation.

15.
J Immunol ; 2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34452933

RESUMO

Immune cell responses are strikingly altered in patients with severe coronavirus disease 2019 (COVID-19), but the immunoregulatory process in these individuals is not fully understood. In this study, 23 patients with mild and 22 patients with severe COVID-19 and 6 asymptomatic carriers of COVID-19 were enrolled, along with 44 healthy controls (HC). Peripheral immune cells in HC and patients with COVID-19 were comprehensively profiled using mass cytometry. We found that in patients with severe COVID-19, the number of HLA-DRlow/- monocytes was significantly increased, but that of mucosal-associated invariant T (MAIT) cells was greatly reduced. MAIT cells were highly activated but functionally impaired in response to Escherichia coli and IL-12/IL-18 stimulation in patients with severe COVID-19, especially those with microbial coinfection. Single-cell transcriptome analysis revealed that IFN-stimulated genes were significantly upregulated in peripheral MAIT cells and monocytes from patients with severe COVID-19. IFN-α pretreatment suppressed MAIT cells' response to E. coli by triggering high levels of IL-10 production by HLA-DRlow/--suppressive monocytes. Blocking IFN-α or IL-10 receptors rescued MAIT cell function in patients with severe COVID-19. Moreover, plasma from patients with severe COVID-19 inhibited HLA-DR expression by monocytes through IL-10. These data indicate a unique pattern of immune dysregulation in severe COVID-19, which is characterized by enrichment of suppressive HLA-DRlow/- monocytes associated with functional impairment of MAIT cells through the IFN/IL-10 pathway.

16.
Curr Opin Psychol ; 43: 65-69, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34298201

RESUMO

Many citizens distrust powerful societal institutions, and hold conspiracy theories about them. What are the implications of this suspicion of institutions for people's social relationships? The current paper proposes that institutions have at least two functions to regulate citizens' social relationships: providing people with a sense of safety, and providing models for group norms and values. Suspicion of institutions undermines both of these functions, and therefore yields a range of negative societal outcomes by impacting people's interpersonal, within-group, and between-group relationships. More specifically, suspicion of institutions reduces trust between strangers, within-group cooperation, commitment, and prosocial behavior, and increases prejudice, intergroup conflict, polarization, and extremism. We conclude that institutional distrust and conspiracy theories erode the fabric of society.

17.
Nano Lett ; 2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34324350

RESUMO

Lower coercivity (HC) and magnetic anisotropy (K1) coupled with high mechanical strength are essential properties for Co-based soft magnetic thin films; however, the strength-coercivity trade-off limits their development. Co with face centered cubic structure (fcc) exhibits lower HC and K1 than its grand hexagonal close packed structure (hcp); however, metastable fcc-phase Co is hard to stabilize. Here, by using Cu (100) seed layer, we synthesized micron-thick fcc Co films with self-formed three-dimensional nanoscale stacking faults (3D-nSFs) that could achieve high strengths without sacrificing soft magnetic properties. The 3D-nSFs, induced by the Co/Cu interface, could not only stabilize the metastable fcc Co to yield lower HC but also impede dislocation motion to strengthen Co films. More importantly, we successfully tailored the density of 3D-nSFs and confirmed a large variation in magnetic coercivity (by 100%) and indentation hardness (by 25%). This work provides a new strategy for integrated performance optimization by interface design and strain engineering.

18.
Med Phys ; 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34252216

RESUMO

PURPOSE: Clinically, single radiotracer positron emission tomography (PET) imaging is a commonly used examination method; however, since each radioactive tracer reflects the information of only one kind of cell, it easily causes false negatives or false positives in disease diagnosis. Therefore, reasonably combining two or more radiotracers is recommended to improve the accuracy of diagnosis and the sensitivity and specificity of the disease when conditions permit. METHODS: This paper proposes incorporating 18 F-fluorodeoxyglucose (FDG) as a higher-quality PET image to guide the reconstruction of other lower-count 11 C-methionine (MET) PET datasets to compensate for the lower image quality by a popular kernel algorithm. Specifically, the FDG prior is needed to extract kernel features, and these features were used to build a kernel matrix using a k-nearest-neighbor (kNN) search for MET image reconstruction. We created a 2-D brain phantom to validate the proposed method by simulating sinogram data containing Poisson random noise and quantitatively compared the performance of the proposed FDG-guided kernelized expectation maximization (KEM) method with the performance of Gaussian and non-local means (NLM) smoothed maximum likelihood expectation maximization (MLEM), MR-guided KEM, and multi-guided-S KEM algorithms. Mismatch experiments between FDG/MR and MET data were also carried out to investigate the outcomes of possible clinical situations. RESULTS: In the simulation study, the proposed method outperformed the other algorithms by at least 3.11% in the signal-to-noise ratio (SNR) and 0.68% in the contrast recovery coefficient (CRC), and it reduced the mean absolute error (MAE) by 8.07%. Regarding the tumor in the reconstructed image, the proposed method contained more pathological information. Furthermore, the proposed method was still superior to the MR-guided KEM method in the mismatch experiments. CONCLUSIONS: The proposed FDG-guided KEM algorithm can effectively utilize and compensate for the tissue metabolism information obtained from dual-tracer PET to maximize the advantages of PET imaging.

19.
Small ; 17(34): e2101183, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34270853

RESUMO

CD8+ T cell responses play a critical regulatory role in protection against mycoplasma infection-related respiratory diseases. Nanovesicles derived from cell membranes have been shown to induce CD8+ T cell responses. Moreover, the short residence time of mycoplasma membrane-related vaccines in local lymph nodes limits the efficacy of current mycoplasma vaccines. Here, a long-residence pneumonia vaccine is developed using nanovesicles prepared by cell membrane fusion of Mycoplasma hyopneumoniae and interferon-γ (IFN-γ  )-primed macrophages, which are grafted with polyethylene glycol to increase residence time in the lymph nodes. Upregulation of intercellular adhesion molecule-1 (ICAM-1) on the membrane of IFN-γ-primed macrophages increases the targeting of the hybrid nanovesicle vaccine to the local lymph nodes, with increased CD8+ T cell activation. A mechanistic study reveals that CD8+ T cell activation is achieved via a pathway involving upregulation of C-C motif chemokine ligand 2/3 expression by E26 transformation-specific sequences, followed by increased immune-stimulatory activity of dendritic cells. In vivo, prophylactic testing reveals that the hybrid nanovesicle vaccine triggers a long-term immune response, as evidenced by a memory CD8+ T cell response against mycoplasma infection. The current study provides a new design strategy for mycoplasma vaccines that involves a hybrid method using biological sources and artificial modification.

20.
J Microbiol Biotechnol ; 31(8): 1069-1078, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34226409

RESUMO

Sevoflurane postconditioning (SPostC) has been proved effective in cardioprotection against myocardial ischemia/reperfusion injury. It was also reported that heat shock protein 70 (HSP70) could be induced by sevoflurane, which played a crucial role in hypoxic/reoxygenation (HR) injury of cardiomyocytes. However, the mechanism by which sevoflurane protects cardiomyocytes via HSP70 is still not understood. Here, we aimed to investigate the related mechanisms of SPostC inducing HSP70 expression to reduce the HR injury of cardiomyocytes. After the HR cardiomyocytes model was established, the cells transfected with siRNA for HSP70 (siHSP70) or not were treated with sevoflurane during reoxygenation. The lactate dehydrogenase (LDH) level was detected by colorimetry while cell viability and apoptosis were detected by MTT and flow cytometry. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and Western blotting were used to detect HSP70, apoptosis-, cell cycle-associated factors, iNOS, and Cox-2 expressions. Enzyme-linked immuno sorbent assay (ELISA) was used to measure malondialdehyde (MDA) and superoxide dismutase (SOD). SPostC decreased apoptosis, cell injury, oxidative stress and inflammation and increased viability of HR-induced cardiomyocytes. In addition, SPostC downregulated Bax and cleaved caspase-3 levels, while SPostC upregulated Bcl-2, CDK-4, Cyclin D1, and HSP70 levels. SiHSP70 had the opposite effect that SPostC had on HR-induced cardiomyocytes. Moreover, siHSP70 further reversed the effect of SPostC on apoptosis, cell injury, oxidative stress, inflammation, viability and the expressions of HSP70, apoptosis-, and cell cycle-associated factors in HR-induced cardiomyocytes. In conclusion, this study demonstrates that SPostC can reduce the HR injury of cardiomyocytes by inducing HSP70 expression.

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