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1.
Light Sci Appl ; 11(1): 136, 2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35562360

RESUMO

The growing demand for spectroscopy applications in the areas of agriculture, retail and healthcare has led to extensive research on infrared light sources. The ability of phosphors to absorb blue light from commercial LED and convert the excitation energy into long-wavelength infrared luminescence is crucial for the design of cost-effective and high-performance phosphor-converted infrared LEDs. However, the lack of ideal blue-pumped short-wave infrared (SWIR) phosphors with an emission peak longer than 900 nm greatly limits the development of SWIR LEDs using light converter technology. Here we have developed a series of SWIR-emitting materials with high luminescence efficiency and excellent thermal stability by co-doping Cr3+-Yb3+ ion pairs into Lu0.2Sc0.8BO3 host materials. Benefitting from strong light absorption of Cr3+ in the blue waveband and very efficient Cr3+→Yb3+ energy transfer, the as-synthesized Lu0.2Sc0.8BO3:Cr3+,Yb3+ phosphor emits intense SWIR light in the 900-1200 nm from Yb3+ under excitation with blue light at ~460 nm. The optimized phosphor presents an internal quantum yield of 73.6% and the SWIR luminescence intensity at 100 °C can still keep 88.4% of the starting value at 25 °C. SWIR LED prototype device based on Lu0.2Sc0.8BO3:Cr3+,Yb3+ phosphor exhibits exceptional luminescence performance, delivering SWIR radiant power of 18.4 mW with 9.3% of blue-to-SWIR power conversion efficiency and 5.0% of electricity-to-SWIR light energy conversion efficiency at 120 mA driving current. Moreover, under the illumination of high-power SWIR LED, covert information identification and night vision lighting have been realized, demonstrating a very bright prospect for practical applications.

2.
Front Microbiol ; 13: 897752, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35572642

RESUMO

Varicella-zoster virus (VZV), a highly infectious agent that causes varicella (chickenpox), can also cause zoster (shingles), a disorder that is frequently associated with severe neuralgia. A reliable serological VZV diagnostic assay would be useful for identifying unprotected individuals and for surveilling post-vaccination immunoprotection status. Toward this goal, VZV membrane glycoprotein E (gE), the immunodominant VZV protein, served as target antigen in an indirect ELISA kit developed here to detect anti-VZV antibodies in clinical samples. For target antigen preparation, Chinese hamster ovary (CHO) cells were modified to express and secrete the VZV gE ectodomain, which was subsequently purified and used as coating antigen in an indirect ELISA. Ultimately, the optimal purified gE coating antigen concentration was determined to be 2 µg.ml-1 and the OD450nm detection cutoff value was 0.286. The coefficient of variation (CV) of intra-assay and inter-assay were <10 and 15%, respectively. A comparative test of 66 clinical samples showed that the coincidence rate was 93.9% between the indirect ELISA and a commercial varicella-zoster virus IgG ELISA kit. Thus, the indirect ELISA kit developed here may be useful for achieving rapid, sensitive, and specific detection of anti-VZV antibodies.

3.
Front Bioeng Biotechnol ; 10: 870445, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35573228

RESUMO

Wet adhesion technology has potential applications in various fields, especially in the biomedical field, yet it has not been completely mastered by humans. Many aquatic organisms (e.g., mussels, sandcastle worms, and barnacles) have evolved into wet adhesion specialists with excellent underwater adhesion abilities, and mimicking their adhesion principles to engineer artificial adhesive materials offers an important avenue to address the wet adhesion issue. The crustacean barnacle secretes a proteinaceous adhesive called barnacle cement, with which they firmly attach their bodies to almost any substrate underwater. Owing to the unique chemical composition, structural property, and adhesion mechanism, barnacle cement has attracted widespread research interest as a novel model for designing biomimetic adhesive materials, with significant progress being made. To further boost the development of barnacle cement-inspired adhesive materials (BCIAMs), it is necessary to systematically summarize their design strategies and research advances. However, no relevant reviews have been published yet. In this context, we presented a systematic review for the first time. First, we introduced the underwater adhesion principles of natural barnacle cement, which lay the basis for the design of BCIAMs. Subsequently, we classified the BCIAMs into three major categories according to the different design strategies and summarized their research advances in great detail. Finally, we discussed the research challenge and future trends of this field. We believe that this review can not only improve our understanding of the molecular mechanism of barnacle underwater adhesion but also accelerate the development of barnacle-inspired wet adhesion technology.

5.
Andrologia ; : e14455, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35560069

RESUMO

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is a poorly understood disease. Accumulating evidence suggests that autoimmune dysfunction is involved in the development of CP/CPPS. Interleukin-17 (IL-17) is associated with the occurrence and development of several chronic autoimmune inflammatory diseases. However, the molecular mechanisms underlying the role of IL-17 in CP/CPPS are not clear. We confirmed that IL-17 was increased in the prostate tissues of experimental autoimmune prostatitis (EAP) mice. Corresponding to the increase of IL-17, neutrophil infiltration and the levels of CXCL1 and CXCL2 (CXC chemokine ligands 1 and 2) were also increased in the prostate of EAP. Treatment of EAP mice with an IL-17-neutralizing monoclonal antibody (mAb) decreased the number of infiltrated neutrophils and CXCL1 and CXCL2 levels. Depletion of neutrophils using anti-Ly6G antibodies ameliorated the inflammatory changes and hyperalgesia caused by EAP. Fucoidan, a could potent inhibitor of neutrophil migration, also ameliorate the manifestations of EAP. Our findings suggested that IL-17 promoted the production of CXCL1 and CXCL2, which triggered neutrophil chemotaxis to prostate tissues. Fucoidan might be a potential drug for the treatment of EAP via the effective inhibition of neutrophil infiltration.

6.
Microb Pathog ; : 105572, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35561978

RESUMO

The protective effect of cinnamaldehyde on channel catfish infected by drug-resistant Aeromonas hydrophila CW strain was explored by observing the clinical symptoms and histopathology, measuring the cumulative mortality, serum biochemical and non-specific immune indicators, and intestinal microbiota in this study. The cumulative survival rate of the cinnamaldehyde within 14 days was significantly higher than that of the challenge group, which was 70% and 20%, respectively. Compared with the challenge group, the activities of lysozyme, superoxide dismutase, and glutathione peroxidase in the treatment group were increased, while there was no significant difference in catalase activity. Compared with the challenge group, the histopathology results showed that the injury of liver, spleen, and kidney was significantly alleviated after cinnamaldehyde treatment. The results of intestinal microbiota showed that the proportion of Proteobacteria in the challenge group was significantly increased, and the proportion of Aeromonas sp. reached 30% based on the analysis of species classification level. The composition of dominant species in the treatment group was similar to the control group. In conclusion, cinnamaldehyde increased the cumulative survival rate of channel catfish infected by A. hydrophila. It could protect channel catfish through improving the non-specific immune function of channel catfish, alleviating the pathological lesions of liver, spleen, kidney, and intestine, and maintaining the relative balance of the intestinal microbiota. Therefore, cinnamaldehyde could be a candidate drug for the treatment of A. hydrophila infection.

7.
Nat Commun ; 13(1): 2245, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35473926

RESUMO

The limited therapeutic effect on hypoxic and refractory solid tumors has hindered the practical application of photodynamic therapy. Herein, we report our investigation of an osmium-peroxo complex (Os2), which is inactive in the dark, but can release a peroxo ligand O2•- upon light irradiation even in the absence of oxygen, and is transformed into a cytotoxic osmium complex (Os1). Os1 is cytotoxic in the presence or absence of irradiation in hypoxic tumors, behaving as a chemotherapeutic drug. At the same time, the light-activated Os2 induces photocatalytic oxidation of endogenous 1,4-dihydronicotinamide adenine dinucleotide in living cancer cells, leading to ferroptosis, which is mediated by glutathione degradation, lipid peroxide accumulation and down-regulation of glutathione peroxidase 4. In vivo studies have confirmed that the Os2 can effectively inhibit the growth of solid hypoxic tumors in mice. A promising strategy is proposed for the treatment of hypoxic tumors with metal-based drugs.


Assuntos
Antineoplásicos , Neoplasias , Fotoquimioterapia , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Hipóxia/metabolismo , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Osmio , Oxigênio
8.
Am J Transl Res ; 14(3): 1892-1900, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35422927

RESUMO

OBJECTIVE: To explore the expression of plasma CTRP3 in patients with non-valvular paroxysmal atrial fibrillation after radiofrequency ablation and its predictive value for disease recurrence. METHODS: In this retrospective study, the patients in the Heart Center of Beijing Chaoyang Hospital from June 2016 to November 2017 were collected. According to the guidelines for diagnosis and treatment of atrial fibrillation 2016, patients diagnosed with paroxysmal atrial fibrillation were selected as the study subjects. All patients with successful radiofrequency ablation of atrial fibrillation were followed up by telephone or outpatient service at 1, 3, 6 and 12 months after radiofrequency ablation, respectively. Recurrence of atrial fibrillation was defined as a duration of rapid atrial arrhythmia ≥30 seconds confirmed by electrocardiogram or 24-hour ambulatory electrocardiogram 3 months after radiofrequency ablation. According to the follow-up results, the patients were divided into a recurrent group and non-recurrent group. The level of CTRP3 was detected by enzyme-linked immunosorbent assay (ELISA). RESULTS: Analysis of clinical baseline data showed significant differences between the recurrent group and the non-recurrent group in age, systolic blood pressure, diastolic blood pressure, EGFR, thyroid stimulating hormone level, platelet count, high-sensitivity C-reactive protein, NT proBNP, left atrial anterior posterior diameter, left atrial upper and lower diameter and CTRP3 (P < 0.05). The univariate logistic regression showed that older age (or = 1.08, P < 0.001), increased diastolic blood pressure (OR = 1.051, P = 0.002), cardiac dysfunction (OR = 2.594, P = 0.01), high-sensitivity C-reactive protein (OR = 1.134, P = 0.008) and NT proBNP (OR = 1.000, P = 0.005), increased anterior posterior diameter of left atrium (OR = 1.158, P < 0.001), increased upper and lower diameter of left atrium (OR = 1.133, P < 0.001), thrombocytopenia (OR = -0.008, P < 0.027) and CTRP3 (OR = 1.007, P = 0.006) were the risk factors for the recurrence of atrial fibrillation after radiofrequency ablation. Moreover, the multivariate logistic regression analysis demonstrated that CTRP3 (or = 1.032, P = 0.005) was an independent predictor of recurrence. CONCLUSION: The plasma concentration of CTRP3 increased significantly in patients with recurrent atrial fibrillation after radiofrequency ablation. Moreover, CTRP3 was a predictor of recurrence after radiofrequency ablation in patients with atrial fibrillation.

9.
Biomed Res Int ; 2022: 3529499, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35463973

RESUMO

In order to explore the effect of treadmill exercise on mitochondrial DNA damage and myocardial telomerase activity in aging model rats based on the classical apoptosis signaling pathway, a total of 36 clean-grade male SD rats are selected. After modeling, the rats are randomly divided into groups, namely, control and 3 times/w and 6 times/w exercise rats, with 12 rats in each group. After the rats of each group are modeled, the myocardial tissue and cells are collected, the apoptosis of myocardial cells is detected by TUNEL method, and the protein expressions of Bax and Bcl-2 in myocardial tissue are detected by western blotting. The mtDNA content of the control rats is the highest, which is significantly higher than that of the exercise group (P < 0.05); the expression of mtDNA content in the heart of the rats exercising 3 times/w is significantly higher than that of the rats exercising 6 times/w (P < 0.05); cardiomyocyte apoptosis AI value, Bcl-2, and Bax expressions of the control rats is the highest and significantly higher than those in the exercise group (P < 0.05); Bcl-2/Bax in the control rats is the lowest and is significantly lower than that in the exercise group (P < 0.05). The AI value, Bcl-2, and Bax expression of myocardial cell apoptosis in 3 times/w exercise rats are significantly higher than those in 6 times/w exercise rats (P < 0.05); Bcl-2/Bax of 3 times/w exercise rats is significantly lower than that in 6 times/w exercise rats (P < 0.05); by observing the rats that completed treadmill exercise, Akt2 protein of 3 times/w exercise rats and 6 times/w exercise rats is observed and analyzed. Compared with the control rats, the expressions of the two proteins are increased in 3 times/w exercise rats and 6 times/w exercise rats, and the upregulation in 6 times/w exercise rats is significantly increased and higher than that in 3 times/w exercise rats (P < 0.05). For aging rats, treadmill exercise can reduce the body Bcl-2 and Bax values, improve the mitochondrial DNA damage and myocardial cell telomerase activity in aging model rats, and slow down the aging process.


Assuntos
Envelhecimento , DNA Mitocondrial , Terapia por Exercício , Miócitos Cardíacos , Telomerase , Envelhecimento/genética , Envelhecimento/metabolismo , Animais , Apoptose , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Terapia por Exercício/métodos , Masculino , Miócitos Cardíacos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Telomerase/genética , Telomerase/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
10.
IEEE Trans Image Process ; 31: 3182-3196, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35412982

RESUMO

Due to balanced accuracy and speed, one-shot models which jointly learn detection and identification embeddings, have drawn great attention in multi-object tracking (MOT). However, the inherent differences and relations between detection and re-identification (ReID) are unconsciously overlooked because of treating them as two isolated tasks in the one-shot tracking paradigm. This leads to inferior performance compared with existing two-stage methods. In this paper, we first dissect the reasoning process for these two tasks, which reveals that the competition between them inevitably would destroy task-dependent representations learning. To tackle this problem, we propose a novel reciprocal network (REN) with a self-relation and cross-relation design so that to impel each branch to better learn task-dependent representations. The proposed model aims to alleviate the deleterious tasks competition, meanwhile improve the cooperation between detection and ReID. Furthermore, we introduce a scale-aware attention network (SAAN) that prevents semantic level misalignment to improve the association capability of ID embeddings. By integrating the two delicately designed networks into a one-shot online MOT system, we construct a strong MOT tracker, namely CSTrack. Our tracker achieves the state-of-the-art performance on MOT16, MOT17 and MOT20 datasets, without other bells and whistles. Moreover, CSTrack is efficient and runs at 16.4 FPS on a single modern GPU, and its lightweight version even runs at 34.6 FPS. The complete code has been released at https://github.com/JudasDie/SOTS.

11.
J Ethnopharmacol ; 294: 115323, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35483559

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: In traditional Chinese medicine (TCM), Zuogui Wan (ZGW) is a classical prescription for senile disorders and delay aging. Modern studies show that ZGW promotes central nerve cell regeneration, prevents and cures osteoporosis, enhances the body's antioxidant capacity, regulates the body's immune function, and promotes mesenchymal stem cells (MSCs) proliferation. AIM OF THE STUDY: It has been shown that MSCs aging is closely associated with organism's aging and age-related disorders. The study aimed to define the effects of ZGW on the aging bone marrow mesenchymal stem cells (BMSCs) and to identify the mechanisms of ZGW delaying BMSCs senescence. MATERIALS AND METHODS: Network pharmacology analysis combined with GEO data mining, molecular docking and experimental validation were used to evaluate the mechanisms by which ZGW delays MSCs senescence (MSCS). LC-MS was used for quality control analysis of ZGW. RESULTS: PPI network analysis revealed that EGF, TNF, JUN, MMPs, IL-6, MAPK8, and MYC are components of the core PPI network. GO and KEGG analyses revealed that oxidative stress, regulation of response to DNA damage stimuli, and Wnt signaling were significantly enriched. GEO database validation also indicated that Wnt signaling closely correlated with MSCs aging. Molecular docking analysis of the top-13 active components in the "ZGW-Targets-MSCS" network indicated that most components have strong affinity for key proteins in Wnt signaling, suggesting that modulation of Wnt signaling is an important mechanism of ZGW activity against MSCS. Further experimental validation found that ZGW indeed regulates Wnt signaling and suppresses the expression of age-related factors to enhance cell proliferation, ameliorate DNA damage, and reduce senescence-related secretory phenotype (SASP) secretion, thereby maintaining multidirectional differentiation of rat BMSCs. Similar results were obtained using the Wnt inhibitor, XAV-939. CONCLUSIONS: Together, our data show that ZGW slows BMSCs aging by suppressing Wnt signaling.

12.
IEEE Trans Image Process ; 31: 3056-3065, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35385381

RESUMO

Zero-shot recognition has been a hot topic in recent years. Since no direct supervision is available, researchers use semantic information as the bridge instead. However, most zero-shot recognition methods jointly model images on the class level without considering the distinctive character of each image. To solve this problem, in this paper, we propose a novel exemplar-based, semantic guided zero-shot recognition method (EBSG). Both visual and semantic information of each image is used. We train visual sub-model to separate each image from the other images of different classes. We also train semantic sub-model to separate this image from the other images described with different semantics. We concatenate the outputs of visual and semantic sub-models to represent images. Image classification model is then learned by measuring visual similarity and semantic consistency of both source and target images. We conduct zero-shot recognition experiments on four widely used datasets. Experimental results show the effectiveness of the proposed EBSG method.

13.
ACS Omega ; 7(12): 10820-10839, 2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35382284

RESUMO

Pore types and pore structure parameters are the important factors affecting the storage capacity of a shale oil reservoir. Pore morphology and mineralogical composition of shales have diverse effects on the upgrading of various phases of shale oil. To interpret the formation and distribution of different pore types and their structure parameters in the lacustrine calcareous shale, a combination of polarizing microscopy, X-ray diffraction, total organic carbon (TOC), field-emission scanning electron microscopy, and low-pressure nitrogen adsorption experiments were conducted on the Es3x shale of the Eocene Shahejie Formation in the Zhanhua Depression. The interpretations regarding pore types, pore structure parameters, and pore size distribution indicate that the pore morphology and pore size distribution in the lacustrine shale are very complicated and demonstrate strong heterogenic behavior. Inorganic pores (interparticle pores, intraparticle pores, intercrystalline pores, dissolution pores, and microfractures) are the most commonly distributed pore types in the studied shale. However, organic matter pores are poorly developed due to the lower thermal maturity of the Es3x shale. The Brunauer-Emmett-Teller specific surface and pore volume range from 0.026 to 1.282 m2/g (average 0.697 m2/g) and 0.003 to 0.008 cm3/g (average 0.005 cm3/g), respectively. The shape of the pores varies from slit-like to narrow slit. Different minerals develop different types of pores with various sizes extending from micropores (<2 nm), mesopores (2-50 nm), to macropores (>50 nm). The relationship between mineral components and pore parameters indicates that the carbonate minerals act as the main contributors to the formation and distribution of different pore types in the studied shale. Pore volume and the pore specific surface area did not show a good relationship with mineral composition and TOC due to disordered pores, but pore size shows a good relationship with mineral composition and TOC of the Es3x shale. The whole pore system description showed that the mesopores and macropores are abundantly distributed and are the main contributors to the pore system in the Es3x shale. A comprehensive understanding of the formation mechanism and structural features of various sized pores in a variety of different minerals can provide a good tool for the exploration and development of shale oil reservoirs.

14.
Int Microbiol ; 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35438439

RESUMO

Aeromonas hydrophila is a common pathogen in fish that has caused severe economic losses in aquaculture worldwide. With the emergence of bacterial resistance, it is necessary to develop new drugs to combat bacterial infection, particularly for multidrug-resistant bacteria. In this study, the antibacterial activity of pinocembrin was investigated by observing bacterial growth and microscopic structure, and its mechanism of action was identified by investigating its effect on protein and DNA. The antibacterial susceptibility test indicated that pinocembrin inhibits A. hydrophila growth. The minimal inhibitory concentration and minimum bactericidal concentration were 256 µg/mL and 512 µg/mL, respectively. Ultrastructurally, the bacteria treated with pinocembrin showed surface roughness and plasmolysis. When bacteria were treated with 512 µg/mL pinocembrin, lactate dehydrogenase activity and soluble protein content decreased significantly, and electrical conductivity and DNA exosmosis levels increased by 4.21 ± 0.64% and 15.98 ± 1.93 mg/L, respectively. Staining with 4', 6-Diamidino-2-phenylindole showed that the nucleic acid fluorescence intensity and density decreased after the treatment with pinocembrin. Pinocembrin may inhibit the growth of A. hydrophila by increasing cell membrane permeability and affecting protein and DNA metabolism. Thus, pinocembrin is a candidate drug for the treatment of A. hydrophila infection in aquaculture.

15.
Front Med (Lausanne) ; 9: 827585, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35479959

RESUMO

Traumatic brain injury (TBI) is a major global burden of health. As an accepted inflammatory mediator, high mobility group box 1 (HMGB1) is found to be effective in facilitating neurogenesis and axonal regeneration. SH3RF2 (also known as POSHER), an E3 ligase SH3 domain-containing ring finger 2, belongs to the SH3RF family of proteins. Here, we aimed to investigate the role of redox states of HMGB1 on neurite outgrowth and regeneration both in vitro and in vivo. In this study, distinct recombinant HMGB1 redox isoforms were used. Sequencing for RNA-seq and data analysis were performed to find the potential downstream target of nonoxid-HMGB1 (3S-HMGB1). Protein changes and distribution of SH3RF2 were evaluated by western blot assays and immunofluorescence. Lentivirus and adeno-associated virus were used to regulate the expression of genes. Nonoxid-HMGB1-enriched exosomes were constructed and used to treat TBI rats. Neurological function was evaluated by OF test and NOR test. Results demonstrated that nonoxid-HMGB1 and fr-HMGB1, but not ds-HMGB1, promoted neurite outgrowth and axon elongation. RNA-seq and western blot assay indicated a significant increase of SH3RF2 in neurons after treated with nonoxid-HMGB1 or fr-HMGB1. Notably, the beneficial effects of nonoxid-HMGB1 were attenuated by downregulation of SH3RF2. Furthermore, nonoxid-HMGB1 ameliorated cognitive impairment in rats post-TBI via SH3RF2. Altogether, our experimental results suggest that one of the promoting neurite outgrowth and regeneration mechanisms of nonoxid-HMGB1 is mediated through the upregulated expression of SH3RF2. Nonoxid-HMGB1 is an attractive therapeutic candidate for the treatment of TBI.

16.
Biomacromolecules ; 23(5): 2019-2030, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35482604

RESUMO

Peptides capable of self-assembling into different supramolecular structures have potential applications in a variety of areas. The biomimetic molecular design offers an important avenue to discover novel self-assembling peptides. Despite this, a lot of biomimetic self-assembling peptides have been reported so far; to continually expand the scope of peptide self-assembly, it is necessary to find out more novel self-assembling peptides. Barnacle cp19k, a key underwater adhesive protein, shows special block copolymer-like characteristics and diversified self-assembly properties, providing an ideal template for biomimetic peptide design. In this study, inspired by Balanus albicostatus cp19k (Balcp19k), we rationally designed nine biomimetic peptides (P1-P9) and systematically studied their self-assembly behaviors for the first time. Combining microscale morphology observations and secondary structure analyses, we found that multiple biomimetic peptides derived from the central region and the C-terminus of Balcp19k form distinct supramolecular structures via different self-assembly mechanisms under acidic conditions. Specifically, P9 self-assembles into typical amyloid fibers. P7, which resembles ionic self-complementary peptides by containing nonstrictly alternating hydrophobic and charged amino acids, self-assembles into uniform, discrete nanofibers. P6 with amphipathic features forms twisted nanoribbons. Most interestingly, P4 self-assembles to form helical nanofibers and novel ring-shaped microstructures, showing unique self-assembly behaviors. Apart from their self-assembly properties, these peptides showed good cytocompatibility and demonstrated promising applications in biomedical areas. Our results expanded the repertoire of self-assembling peptides and provided new insights into the structure-function relationship of barnacle cp19k.


Assuntos
Nanofibras , Thoracica , Adesivos/química , Animais , Nanofibras/química , Peptídeos/química , Polímeros , Estrutura Secundária de Proteína , Thoracica/química
17.
Nat Commun ; 13(1): 1217, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35260568

RESUMO

MicroRNAs (miRNAs) play crucial roles in gene expression regulation through RNA cleavage or translation repression. Here, we report the identification of an evolutionarily conserved WD40 domain protein as a player in miRNA biogenesis in Arabidopsis thaliana. A mutation in the REDUCTION IN BLEACHED VEIN AREA (RBV) gene encoding a WD40 domain protein led to the suppression of leaf bleaching caused by an artificial miRNA; the mutation also led to a global reduction in the accumulation of endogenous miRNAs. The nuclear protein RBV promotes the transcription of MIR genes into pri-miRNAs by enhancing the occupancy of RNA polymerase II (Pol II) at MIR gene promoters. RBV also promotes the loading of miRNAs into AGO1. In addition, RNA-seq revealed a global splicing defect in the mutant. Thus, this evolutionarily conserved, nuclear WD40 domain protein acts in miRNA biogenesis and RNA splicing.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas Argonauta , MicroRNAs , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas Argonauta/genética , Proteínas Argonauta/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Nucleares/metabolismo , Repetições WD40
18.
Oncogene ; 41(13): 1986-2002, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35236967

RESUMO

Inhibitors of the mitotic kinase PLK1 yield objective responses in a subset of refractory cancers. However, PLK1 overexpression in cancer does not correlate with drug sensitivity, and the clinical development of PLK1 inhibitors has been hampered by the lack of patient selection marker. Using a high-throughput chemical screen, we discovered that cells deficient for the tumor suppressor ARID1A are highly sensitive to PLK1 inhibition. Interestingly this sensitivity was unrelated to canonical functions of PLK1 in mediating G2/M cell cycle transition. Instead, a whole-genome CRISPR screen revealed PLK1 inhibitor sensitivity in ARID1A deficient cells to be dependent on the mitochondrial translation machinery. We find that ARID1A knock-out (KO) cells have an unusual mitochondrial phenotype with aberrant biogenesis, increased oxygen consumption/expression of oxidative phosphorylation genes, but without increased ATP production. Using expansion microscopy and biochemical fractionation, we see that a subset of PLK1 localizes to the mitochondria in interphase cells. Inhibition of PLK1 in ARID1A KO cells further uncouples oxygen consumption from ATP production, with subsequent membrane depolarization and apoptosis. Knockdown of specific subunits of the mitochondrial ribosome reverses PLK1-inhibitor induced apoptosis in ARID1A deficient cells, confirming specificity of the phenotype. Together, these findings highlight a novel interphase role for PLK1 in maintaining mitochondrial fitness under metabolic stress, and a strategy for therapeutic use of PLK1 inhibitors. To translate these findings, we describe a quantitative microscopy assay for assessment of ARID1A protein loss, which could offer a novel patient selection strategy for the clinical development of PLK1 inhibitors in cancer.


Assuntos
Proteínas de Ciclo Celular , Proteínas de Ligação a DNA , Neoplasias , Proteínas Proto-Oncogênicas , Fatores de Transcrição , Trifosfato de Adenosina/metabolismo , Apoptose , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Consumo de Oxigênio , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
19.
Nat Commun ; 13(1): 1229, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35264580

RESUMO

Conceptual and empirical advances in soil biogeochemistry have challenged long-held assumptions about the role of soil micro-organisms in soil organic carbon (SOC) dynamics; yet, rigorous tests of emerging concepts remain sparse. Recent hypotheses suggest that microbial necromass production links plant inputs to SOC accumulation, with high-quality (i.e., rapidly decomposing) plant litter promoting microbial carbon use efficiency, growth, and turnover leading to more mineral stabilization of necromass. We test this hypothesis experimentally and with observations across six eastern US forests, using stable isotopes to measure microbial traits and SOC dynamics. Here we show, in both studies, that microbial growth, efficiency, and turnover are negatively (not positively) related to mineral-associated SOC. In the experiment, stimulation of microbial growth by high-quality litter enhances SOC decomposition, offsetting the positive effect of litter quality on SOC stabilization. We suggest that microbial necromass production is not the primary driver of SOC persistence in temperate forests. Factors such as microbial necromass origin, alternative SOC formation pathways, priming effects, and soil abiotic properties can strongly decouple microbial growth, efficiency, and turnover from mineral-associated SOC.


Assuntos
Carbono , Solo , Florestas , Minerais , Solo/química , Microbiologia do Solo
20.
Ann Palliat Med ; 11(2): 521-531, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35249330

RESUMO

BACKGROUND: Limb hemiplegia is one of the common sequelae of stroke. Physical therapy-based rehabilitation training can rapidly improve limb functioning and muscle strength. This study investigated the effect of physical therapy on the recovery of upper limb motor function by employing a literature search and meta-analysis. METHODS: We searched Embase, The Cochrane Central Register of Controlled Trials library, Wiley online library, PubMed, Ovid, and Clinicaltrials.org for randomized controlled trial (RCT) studies and performed an electronic search with the keyword combinations 'physical therapy/rehabilitation' & 'stroke/post-stroke' & 'upper extremity/upper limb'. After screening the literature for inclusion criteria and assessing the risk of bias, Revman 5.4 software was used for the analysis and to obtain forest and funnel plots. RESULTS: A total of 15 RCTs with 1,081 patients were included in the quantitative analysis for this study. The meta-analysis results showed that compared with conventional therapy, physical therapy improved the upper limb Fugl-Meyer Assessment for Upper Extremity (FMA) scores in convalescent stroke patients (MD =7.27, 95% CI: 4.23-10.32, Z=4.68, P<0.00001), and increased the Functional Independence Measure (FIM) scores (MD =18.82, 95% CI: 6.34-31.30, Z=2.96, P=0.003), the Action Research Arm Test (ARAT) scores (MD =8.84, 95% CI: 6.53-11.15, Z=7.50, P<0.00001), and the Box and Block Test (BBT) scores (MD =6.11, 95% CI: 1.18-11.04, Z=2.43, P=0.02) of patients during the rehabilitation period. DISCUSSION: The use of physical therapy-based rehabilitation training in the recovery period for stroke patients with hemiplegia can improve upper limb movement ability, increase muscle strength, reduce limb pain, and improve the quality of life.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Adulto , Humanos , Modalidades de Fisioterapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Acidente Vascular Cerebral/complicações , Reabilitação do Acidente Vascular Cerebral/métodos , Extremidade Superior/fisiologia
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