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1.
PLoS One ; 15(10): e0240331, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33031392

RESUMO

OBJECTIVE: Melanoma is rare but dangerous skin cancer, and it can spread rather quickly in the advanced stages of the tumor. Abundant evidence suggests the relationship between tumor development and progression and the immune system. A robust gene risk model could provide an accurate prediction of clinical outcomes. The present study aimed to explore a robust signature of immune-related gene pairs (IRGPs) for estimating overall survival (OS) in malignant melanoma. METHODS: Clinical and genetic data of skin cutaneous melanoma (SKCM) patients from The Cancer Genome Atlas (TCGA) was performed as a training dataset to identify candidate IRGPs for the prognosis of melanoma. Two independent datasets from the Gene Expression Omnibus (GEO) database (GSE65904) and TCGA dataset (TCGA-UVM) were selected for external validation. Univariate and multivariate Cox regression analyses were then performed to explore the prognostic power of the IRGPs signature and other clinical factors. CIBERSORTx was applied to estimate the fractions of infiltrated immune cells in bulk tumor tissues. RESULTS: A signature consisted of 33 IRGPs was established which was significantly associated with patients' survival in the TCGA-SKCM dataset (P = 2.0×10-16, Hazard Ratio (HR) = 4.220 (2.909 to 6.122)). We found the IRGPs signature exhibited an independent prognostic factor in all the three independent cohorts in both the univariate and multivariate Cox analysis (P<0.01). The prognostic efficacy of the signature remained unaffected regardless of whether BRAF or NRAS was mutated. As expected, the results were verified in the GSE65904 dataset and the TCGA-UVM dataset. We found an apparent shorter OS in patients of the high-risk group in the GSE65904 dataset (P = 2.1×10-3; HR = 1.988 (1.309 to 3.020)). The trend in the results of the survival analysis in TCGA-UVM was as we expected, but the result was not statistically significant (P = 0.117, HR = 4.263 (1.407 to 12.91)). CD8 T cells, activated dendritic cells (DCs), regulatory T cells (Tregs), and activated CD4 memory T cells presented a significantly lower fraction in the high-risk group in the TCGA-SKCM dataset(P <0.01). CONCLUSION: The results of the present study support the IRGPs signature as a promising marker for prognosis prediction in melanoma.

3.
Zhongguo Zhong Yao Za Zhi ; 45(15): 3642-3650, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32893553

RESUMO

This article is based on basic data such as field surveys and literature surveys, contrasting and analyzing the distribution of Callicarpa nudiflora by different zoning methods, different data sources, and different spatial scales. The results showed that there were certain differences in the distribution results obtained by using different methods, such as qualitative description, similar ecological environment, and niche model, to divide the distribution of the C. nudiflora, but all of them could reflect the distribution of C. nudiflora to different degrees. Among them, the qualitative description division method has certain advantages in macro guidance in a large scale. The distribution range obtained by the ecological environment similar division method is wider than that obtained by applying the qualitative description method and the niche model method. The results of the zoning of the distribution of the C. nudiflora obtained from different data sources were different. The number and representativeness of the survey data have an impact on the zoning results. Through the analysis of the distribution of different spatial scales, the ecological factors and contribution rates that affect the distribution of C. nudiflora are different in China and in the world. The comprehensive multi-source data analysis showed that C. nudiflora mainly distributed in southern coastal provinces such as Hainan, Guangdong, Guangxi and Fujian in China, and also in Jiangxi, Guizhou, Yunnan, Sichuan, Chongqing, Hunan, Gansu, Taiwan and other provinces. Globally, C. nudiflora are suitable for distribution in Southeast Asia, such as China, Vietnam, Laos, Myanmar, India, etc. There are also potential distribution areas in the southern United States and Mexico.


Assuntos
Callicarpa , China , Coleta de Dados , Armazenamento e Recuperação da Informação , Vietnã
4.
Sci Rep ; 10(1): 15730, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32978480

RESUMO

Prunella vulgaris L, a perennial herb widely used in Asia in the treatment of various diseases including cancer. In vitro studies have demonstrated the therapeutic effect of Prunella vulgaris L. against breast cancer through multiple pathways. However, the nature of the biological mechanisms remains unclear. In this study, a Network pharmacology based approach was used to explore active constituents and potential molecular mechanisms of Prunella vulgaris L. for the treatment of breast cancer. The methods adopted included active constituents prescreening, target prediction, GO and KEGG pathway enrichment analysis. Molecular docking experiments were used to further validate network pharmacology results. The predicted results showed that there were 19 active ingredients in Prunella vulgaris L. and 31 potential gene targets including AKT1, EGFR, MYC, and VEGFA. Further, analysis of the potential biological mechanisms of Prunella vulgaris L. against breast cancer was performed by investigating the relationship between the active constituents, target genes and pathways. Network analysis showed that Prunella vulgaris L. exerted a promising preventive effect on breast cancer by acting on tumor-associated signaling pathways. This provides a basis to understand the mechanism of the anti-breast cancer activity of Prunella vulgaris L.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32919704

RESUMO

OBJECTIVE: To investigate the effects of everolimus (EVE) on postoperative fibrosis in the knee joint and the potentially relevant signaling pathways. METHODS: CCK-8 and flow cytometry assays were used to detect the effect of EVE on human fibroblast viability and apoptosis induction. IF and TEM were used to assess fibroblast autophagy. 3-methyladenine (3-MA) was applied to inhibit autophagy to clarify the relationship between autophagy and apoptosis. WB was used to measure the expression of proteins related to apoptosis, autophagy and the mTOR signaling pathway. A rabbit model of knee joint fibrosis was established and topically treated with various concentrations of EVE. IF-P was applied to identify that the main components cells of the fibrotic tissue and histomorphological staining was used to detect the degree of fibrosis and the content of collagen. RESULTS: Histomorphological staining demonstrated that EVE could reduce the degree of postoperative fibrosis and collagen deposition in the knee joint. The results of IF, TEM, flow cytometry assays and WB detection showed that EVE could activate autophagy and induce fibroblasts apoptosis. Meanwhile, the expression levels of p-PI3K, p-Akt, p-mTOR were downregulated with EVE treatment. After the inhibition of autophagy by 3-MA treatment, the increased fibroblasts apoptosis by EVE treatment was partially decreased. CONCLUSION: Everolimus can reduce surgery-induced knee fibrosis by inducing autophagy-mediated fibroblast apoptosis, which may be involved with the regulation of the PI3K/Akt/mTOR signaling pathway.

6.
Med Sci Monit ; 26: e922979, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32931486

RESUMO

BACKGROUND Diabetic nephropathy (DN), the formation of albuminuria, is one of the most important complications seen in diabetic patients. IL-37, an inhibitor of congenital inflammation and immune response, plays an important role in the occurrence and development of diabetes, but its study in DN has not been previously reported. MATERIAL AND METHODS Podocyte transfection techniques were used to overexpress STAT3 and cyclophilin A (CypA). The expression of IL-37, STAT3, and CypA was detected by RT-qPCR and western blot. Cell survival was detected by CCK-8. The expression of inflammatory factors and molecules related to oxidative stress was detected by ELISA and western blot, and cell apoptosis was detected by flow cytometry and western blot. RESULTS The expression of IL-37 was significantly decreased in high glucose-treated podocytes. IL-37 improved the survival rate of podocytes suffering from high glucose-induced apoptosis. It inhibited the expression of the inflammation-related factors tumor necrosis factor alpha (TNF-alpha), IL-1ß, IL-6, malondialdehyde (MDA), and lactate dehydrogenase (LDH), and promoted the expression of superoxide dismutase (SOD) in high glucose-treated podocytes. In addition, IL-37 inhibited the expression of the inflammation-related proteins MCP-1, NLRP3, ASC, and caspase-1. IL-37 also inhibited high glucose-induced apoptosis of podocytes by inhibiting the expression of the apoptosis-related proteins Bax and cleaved caspase-3/6/9, and by promoting the expression of Bcl-2. At the same time, we found that the STAT3/CypA signaling pathway was activated after induction by high glucose, while it was inhibited after treatment with IL-37. Overexpression of STAT3 and CypA inhibited the effects of IL-37 on the alleviation of inflammation and oxidative stress and on the reduction of apoptosis of high glucose-treated podocytes. CONCLUSIONS IL-37 can significantly reduce podocyte inflammation, oxidative stress, and apoptosis induced by high glucose, and can inhibit the STAT3-CypA signaling pathway. Upregulation of the STAT3-CypA signaling pathway can inhibit the protective effect of IL-37 against podocyte injury induced by high glucose.

7.
J Control Release ; 327: 676-687, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32920078

RESUMO

Infectious keratitis caused by bacterial biofilms is one of the main causes of corneal blindness, presenting a serious threat to public health. In this study, matrix metalloproteinase (MMP)-sensitive supramolecular nanoparticles (denoted as MMP-S NPs) were constructed for enhancing photodynamic antibacterial effect against biofilm-associated bacterial keratitis. MMP-S NPs were prepared by host-guest self-assembly of chlorin e6 (Ce6) conjugated ß-cyclodextrin (ß-CD) prodrug (ß-CD-Ce6) and MMP-9-sensitive peptides (YGRKKKRRQRRR-GPLGVRG-EEEEEE) terminated with adamantane (Ad) (Ad-MMP-S PEPs). MMP-S NPs with EEEEEE peptide shell had a negatively charged surface, preventing adhesion to the normal ocular surface or healthy corneal cells, thus enhancing tear retention time. After arriving at the infected lesions, the protective EEEEEE peptide shell of MMP-S NPs was removed, triggered by overexpressed MMP-9 in the keratitis microenvironment. The subsequently exposed cationic peptides helped the nanoparticles penetrate and accumulate in biofilms as well as bind to Gram-negative bacteria Pseudomonas aeruginosa (P. aeruginosa), which eventually improved the photodynamic antibacterial effect. Furthermore, the P. aeruginosa keratitis model verified the high effectiveness of a topical eye drop formulation of MMP-S NPs in killing bacteria by destroying the bacterial membrane as a result of in situ photodynamic activation of reactive oxygen species (ROS) formation under light irradiation. Moreover, the inflammatory response in the cornea was inhibited to a great extent. As a result, further damage to the corneal tissue was completely suppressed. This research provides a viable antibacterial alternative to fight against bacterial keratitis through effective elimination of infectious bacteria and eradication of bacterial biofilms in the cornea.

8.
Sci Rep ; 10(1): 14694, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32895443

RESUMO

The purpose of the study is to evaluate the positive predictive value of the combined pituitary dynamic enhanced MRI (dMRI) and high-dose dexamethasone suppression tests (HDDST) in the diagnosis of Cushing's disease (CD) bypassing bilateral inferior petrosal sinus sampling (BIPSS). A total of 118 patients with Cushing's syndrome (CS), who underwent pituitary dMRI, HDDST and BIPSS were included. Positive predictive value of pituitary dMRI, HDDST, BIPSS and the combined test were calculated and tumor lateralization accuracy was further analyzed. The positive predictive value of the combined pituitary dMRI and HDDST was 98.6%, higher than that of BIPSS. There were 96.8% of patients, who had either negative findings in pituitary dMRI or HDDST, showing centralizing BIPSS results. For tumor lateralization, the accuracy by pituitary dMRI was 88.6%, whereas BIPSS was 57.5%. Therefore, CS patients with both positive findings in pituitary dMRI and HDDST need no further invasive evaluation to establish the definite diagnosis of CD. BIPSS will improve the diagnostic accuracy when negative findings were found in either pituitary dMRI or HDDST.

9.
Biomed Res Int ; 2020: 7147824, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32802870

RESUMO

Background: Though there are several prognostic models, there is no protein-related prognostic model. The aim of this study is to identify possible prognostic-related proteins in bladder urothelial carcinoma and to try to predict the prognosis of bladder urothelial carcinoma based on these proteins. Methods: Profile data and corresponding clinical traits were obtained from The Cancer Proteome Atlas (TCPA) and The Cancer Genome Atlas (TCGA) expression. Survival-associated protein in bladder urothelial carcinoma patients were estimated with Kaplan-Meier (KM) test and COX regression analysis. The potential molecular mechanisms and properties of these bladder urothelial carcinoma-specific proteins were also explored with the help of computational skills. The risk score model was validated in different clinical traits. Sankey diagram representation is for protein correlation. A new prognostic-related risk model based on proteins was developed by using multivariable COX analysis. Next, the alteration of the corresponding genes to the 6 prognostic-related proteins was analyzed. Finally, the relation between the corresponding genes and the immune infiltration was analyzed using the TIMER. Results: Six proteins were identified to be associated with the prognosis of bladder urothelial carcinoma. A prognostic signature based on proteins (BECLIN, EGFR, PKCALPHA, SRC, ANNEXIN1, and AXL) performed moderately in prognostic predictions. The alteration of corresponding genes was in 31(24%) sequenced cases. ANXA1, AXL, and EGFR were positively related to CD8+ T cell. Conclusion: Our results screened six proteins of clinical significance. The importance of a personalized protein signature model in the recognition, surveillance. The abnormal expression of six prognostic-related proteins may be caused by corresponding gene alteration. Furthermore, these proteins may affect survival via the immune infiltration.

10.
Chemosphere ; 263: 127856, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32822929

RESUMO

There is limited evidence regarding the relationship between air pollution and pediatric asthma in developing countries. This study aimed to investigate the association between short-term exposure to ambient air pollutants and pediatric asthma emergency department (ED) visits in Shanghai, China. We collected data on six criteria air pollutants (PM2.5, PM10, NO2, SO2, CO, and O3) and daily ED visits for pediatric asthma patients from 66 hospitals in Shanghai from 2016 to 2018. The generalized additive model combined with polynomial distributed lag model was applied to explore the associations. We fitted two-pollutant models and stratified the analyses by sex, age, and season. In total, we identified 108,817 emergency department visits for pediatric asthma. A 10 µg/m3 increase in the concentrations of PM2.5, NO2, SO2, and O3 was significantly associated with increased risks of pediatric asthma ED visits, with relative risk of pediatric asthma of 1.011 [95% confidence interval (CI): 1.002, 1.021], 1.030 (95%CI: 1.017, 1.043), 1.106 (95%CI: 1.041, 1.174), and 1.009 (95%CI: 1.001, 1.017), respectively. The associations of NO2 remained robust in the two-pollutant models. There were stronger associations for older children (6-18 years) and in warm seasons. The concentration-response curves for pediatric asthma and PM2.5, NO2, SO2, and O3 were steeper at lower and moderate concentrations but became flatter at higher concentrations. This analysis provided evidence that short-term exposure to air pollutants (PM2.5, NO2, SO2, and O3) could increase the risk of asthma exacerbations among children, and health benefits would be gained from improved air quality.

11.
Molecules ; 25(15)2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32731553

RESUMO

G-quadruplex/Hemin (G4/Hemin) complex has been widely used in biocatalysis and analytical applications. Meanwhile, compared with natural proteinous enzyme, its low catalytic activity is still limiting its applications. Even though several methods have been developed to enhance the peroxidation efficiency, the important core of the G4 design based enhancement mechanism is still indistinct. Here, we focus the mechanism study on the two most important microdomains: the iron porphyrin center and the catalytic synergy group within the 3' flanking. These microdomains not only provide the pocket for the combination of substrate, but also offer the axial coordination for the accelerated formation of Compound I (catalytic intermediate). In order to obtain a more suitable space layout to further accelerate the catalytic process, we have used the bases within the 3' flanking to precisely regulate the distance between microdomains. Finally, the position-dependent effect on catalytic enhancement is observed. When dC is positioned at the second-position of 3' flanking, the newly obtained DNAzyme achieves an order of magnitude improvement compared to parent G4/Hemin in catalytic activity. The results highlight the influence of the distance between the catalytic synergy group and iron porphyrin center on the activity of DNAzyme, and provide insightful information for the design of highly active DNAzymes.

12.
Life Sci ; 261: 118360, 2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32861799

RESUMO

AIM: Diabetic patients are reported to have a higher incidence of cataract surgery-induced retinal complications, possibly due to retinal inflammation. Our goal is to identify the key inflammatory cytokines, cells and regulatory pathways involved. MAIN METHODS: Diabetes mellitus (DM) induced by streptozotocin and control mice received extracapsular lens extraction (ECLE) in one eye. Neuroretinas were collected at postoperative day1(P1), day2(P2), and day7(P7). BV2 cells were harvested under the treatment of high glucose, lipopolysaccharide (LPS) and inhibitors. The method of qPCR, western blot and immunohistochemistry were used to identify the expression of cytokines and signaling pathways. KEY FINDINGS: ECLE induced increased inflammation in the neuroretina of surgery eye with a peak at P1. MCP-1 surge in long-term diabetes mellitus (LDM) mice at P1 is higher than short-term diabetes mellitus (SDM) mice and normal mice. Significant activation of c-jun and c-fos were found in LDM compared to normal and SDM. Advanced activation of stat1 and ERK was found at P1 in LDM instead of at P2 in SDM and Normal. Activation of microglia/macrophage was also detected in the LDM mice. Besides the inhibition of c-jun/JNK, MCP-1 expression can be attenuated by inhibiting stat1 and ERK under high glucose condition after LPS stimulation. SIGNIFICANCE: Enhancement of lens extraction-induced MCP-1 upregulation and microglia response in long-term diabetes might be due to the activation of cjun, stat1 and ERK, which provided potential therapeutic targets to attenuate retinal inflammation after surgery in diabetic individuals.

13.
Artigo em Inglês | MEDLINE | ID: mdl-32794611

RESUMO

Stimuli-responsive photodynamic therapy (PDT) is a hot topic in precise medicine, but the low abundance of responsive trigger molecules in early-stage disease limits application. Here we designed an amplifier with multiple upconversion luminances to achieve a near-infrared photo-switched cascade reaction triggered by specific microRNA and precise PDT of early-stage cancers. This amplifier was composed of photo-caged DNA nanocombs and an upconversion nanoparticle (UCNP) sensitized with IRDye 800CW. The nanocomb was prepared by assembling a photozipper-protected hairpin and two kinds of hybridizable hairpin probes on a DNA skeleton. Upon 808-nm light irradiation, the produced UV light cleaved off the photozipper to induce microRNA-responsive cascade hybridization reaction, activating the photosensitizers linked to different hairpins to generate reactive oxygen species (ROS) under the simultaneously emitted blue light for efficient PDT.

15.
Oncol Lett ; 20(2): 1810-1816, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32724424

RESUMO

According to the 2014 World Health Organization Classification of Tumors of Female Reproductive Organs, patients with cervical intraepithelial neoplasia 2 (CIN2) have an equivocal diagnosis, but p16 is considered as the reference index for CIN2. Positive p16 expression in CIN2 is associated with high-grade squamous intraepithelial lesions (HSIL), whereas p16 negative lesions are low-grade squamous intraepithelial lesions. The purpose of the present study was to examine the clinical value of p16 and human papillomavirus (HPV) E6/E7 mRNA in the prognostication of patients with CIN2. From January 2013 to January 2016, 108 patients were diagnosed with CIN2 by biopsy and followed up at 6-month intervals at Peking University People's Hospital (Beijing, China). The expression of HPV E6/E7 mRNA was detected by in situ hybridization, while the expression of p16 and Ki-67 proteins was detected by immunohistochemistry. Of the 108 CIN2 cases, 20 progressed to HSIL/CIN3, 36 cases demonstrated persistence with CIN2 after the follow-up and 52 cases achieved regression (≤CIN1). Of the p16-positive 82 cases, 20 cases were detected to have progressed, whereas in the p16-negative group, no progression was observed. There were statistically significant differences among the p16-positive and negative groups (P<0.05). In the HPV E6/E7 mRNA-positive 69 cases, 18 cases were detected to have progressed, whereas in the HPV E6/E7 mRNA-negative 39 cases, progression was detected in only 2 cases. There were statistically significant differences among the HPV E6/E7 mRNA-positive and negative groups (P<0.05). The area under the receiver operating characteristics curve was plotted; the area under the curve for HPV E6/E7 mRNA was 0.745, that for p16 was 0.546 and that for Ki-67 was 0.501. The detection of HPV E6/E7 mRNA may provide important predictive information for the prognosis of CIN2, however p16 and Ki-67 proteins may provide little value.

16.
Zhongguo Zhong Yao Za Zhi ; 45(13): 3073-3078, 2020 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-32726013

RESUMO

Using the 260 geographical distribution records of Polygonatum cyrtonema in China, combined with 53 environmental factors, the maximum entropy modeling(MaxEnt) was used to study the ecological factors affecting the suitability distribution of P. cyrtonema. The ArcGIS software was used to predict the potential distribution of the population of P. cyrtonema. The dominant factors were chosen by using the Jackknife test and the Receiver Operating Characteristic(ROC) curve was used to evaluate the simulation. The results showed that high value of area under curve(AUC) denoted good results, which significantly differed from random predictions. Based on the evaluation criterion, the accuracies of the predictions of P. cyrtonema potential distribution in the current periods were excellent. The main environmental factors affecting the suitable growth of P. cyrtonema were the monthly precipitation, the wettest monthly precipitation, the annual average temperature range and the precipitation of November, March, February, April, May and October. There are 9 environmental factors in soil type. The potential fitness of P. cyrtonema in China is high, mainly concentra-ted in Hunan, western Hubei, Guangdong, northeastern Guangxi, southeastern Guizhou, Jiangxi, southwestern Anhui, Fujian, Zhejiang, Shaanxi, southwestern Henan and Chongqing. The growth distribution of the potential distribution area of P. cyrtonema was divided, and the zoning map of the growth suitability of P. cyrtonema was formed. Through the comparative analysis of the potential distribution range based on MaxEnt and the distribution range of literature records, the understanding of the distribution range of P. cyrtonema was expanded.


Assuntos
Polygonatum , China , Ecologia , Entropia , Projetos de Pesquisa , Solo
17.
Zhongguo Zhong Yao Za Zhi ; 45(12): 2982-2991, 2020 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-32627476

RESUMO

Dao-di herbs are an important part of clinical medicine in traditional Chinese medicine. They are also precious wealth left to human beings from history, which contain deep traditional Chinese cultural connotations and play an important role in supporting and serving the Chinese medicine business. The relevant policy documents introduced by various national ministries and commissions have many contents and requirements related to the promotion of Dao-di herbs protection and industrial development. Due to the Dao-di herbs industry has a series of characteristics, such as a long chain, many involved links, long cycles, multiple production entities, multiple locations, and various types, the high-quality development of the industry has put forward higher requirements on the linkage between upstream and downstream, production entities, traceability of the whole process and information sharing. This article takes Dao-di herbs certification work as an application scenario and entry point, and discusses it from the perspective of block chain and information technology. It proposes the following work ideas: establish multi-party consensus from the macro-organizational management, business, and operational technical levels, and unblock channels for data and information, to achieve institutionalization of certification; establish certification-related standards and specifications to achieve certification standardization; build a certification hardware system to achieve certification networking; build a certification software system to develop functions for specific information content such as identity, origin, production, production process, quality, product and brand of authentic medicinal material production interactively, and realize certification programmatic; data security and sharing of related production activities to achieve socialization of certification. Make full use of modern technologies such as blockchain, the internet of things, big data and information technology, and through the joint participation of management, production, use and the public, the whole process information of Daodi herbs is integrated to form an interconnected information sharing application mode, thus, to serve and promote the high-quality development of Dao-di herbs industry.


Assuntos
Medicamentos de Ervas Chinesas , Plantas Medicinais , Blockchain , Humanos , Medicina Tradicional Chinesa , Tecnologia
18.
Plant Physiol ; 184(1): 283-299, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32661060

RESUMO

The thylakoid membrane is a highly complex membrane system in plants and plays crucial roles in the biogenesis of the photosynthetic apparatus and plant development. However, the genetic factors involved in chloroplast development and its relationship with intracellular metabolites are largely unknown. Here, a rice (Oryza sativa) chlorotic and necrotic leaf1 (cnl1) mutant was identified and map-based cloning revealed that a single base substitution followed by a 6-bp deletion in the ATP-binding cassette transporter I family member7 (OsABCI7) resulted in chlorotic and necrotic leaves with thylakoid membrane degradation, chlorophyll breakdown, photosynthesis impairment, and cell death in cnl1 Furthermore, the expression of OsABCI7 was inducible under lower temperatures, which severely affected cnl1 chloroplast development, and etiolated cnl1 seedlings were unable to recover to a normal green state under light conditions. Functional complementation and overexpression showed that OsABCI7 could rescue the cnl1 chlorotic and necrotic phenotype. OsABCI7 interacted with HIGH CHLOROPHYLL FLUORESCENCE222 (OsHCF222) to regulate cellular reactive oxygen species (ROS) homeostasis for thylakoid membrane stability. OsABCI7 localized to thylakoid membranes, while OsHCF222 targeted to endoplasmic reticulum and chloroplasts. Exogenous application of ascorbic acid eased the yellowish leaf phenotype by increasing chlorophyll content and alleviating ROS stress in cnl1 Unlike cnl1, the CRISPR/Cas9-mediated OsHCF222 knockout lines showed chlorotic leaves but were seedling lethal. Our results provide insight into the functions of ABC transporters in rice, especially within the relationship between ROS homeostasis and stability of thylakoid membranes.

19.
World J Pediatr ; 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: covidwho-613534

RESUMO

During the COVID-19 epidemic, it is important for ensuring infection prevention and control in the pediatric respiratory clinics. Herein, we introduced the practice of infection prevention and control in pediatric respiratory clinics in China. Triage measures for patients who visit respiratory clinics, quality control for pediatric respiratory clinics and other preventive measures for related examinations and treatment have been introduced in this review article.

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