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1.
Plant Mol Biol ; 2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34826009

RESUMO

KEY MESSAGE: NtCycB2 negatively regulates the initiation of tobacco long stalk glandular trichomes and influences the expression of diterpenoid biosynthesis- and environmental stress resistance-related genes. Many asterid plants possess multicellular trichomes on their surface, both glandular and non-glandular. The CycB2 gene plays a key role in multicellular trichome initiation, but has distinct effects on different types of trichomes; its mechanisms remain unknown. In tomato (Solanum lycopersicum), SlCycB2 negatively regulates non-glandular trichome formation, but its effects on glandular trichomes are ambiguous. In this study, we cloned the SlCycB2 homolog of Nicotiana tabacum, NtCycB2, and analyzed its effect on three types of trichomes, long stalk glandular trichomes (LGT), short stalk glandular trichomes (SGT), and non-glandular trichomes (NGT). Knocking out NtCycB2 (NtCycB2-KO) promoted LGT formation, while overexpression of NtCycB2 (NtCycB2-OE) decreased LGT density. SGT and NGT were not significantly influenced in either NtCycB2-KO or NtCycB2-OE plants, indicating that NtCycB2 regulated only LGT formation in tobacco. In addition, compared with NtCycB2-OE and control plants, NtCycB2-KO plants produced more trichome exudates, including diterpenoids and sugar esters, and exhibited stronger aphid resistance. To further elucidate the function of NtCycB2, RNA-Seq analysis of the NtCycB2-KO, NtCycB2-OE, and control plants was conducted. 2,552 and 1,933 differentially expressed genes (DEGs) were found in NtCycB2-KO and NtCycB2-OE plants, respectively. Gene Ontology analysis of the common DEGs revealed that ion transport, carbohydrate and amino acid metabolism, photosynthesis, and transcription regulation processes were significantly enriched. Among these DEGs, diterpenoid biosynthesis genes were upregulated in NtCycB2-KO plants and downregulated in NtCycB2-OE plants. Two MYB transcription factors and several stress resistance-related genes were also identified, suggesting they may participate in regulating LGT formation and aphid resistance.

2.
Cell Death Discov ; 7(1): 337, 2021 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-34743181

RESUMO

Extracellular vesicles (EVs) have emerged as important vectors of intercellular dialogue. High mobility group box protein 1 (HMGB1) is a typical damage-associated molecular pattern (DAMP) molecule, which is cytotoxic and leads to cell death and tissue injury. Whether EVs are involved in the release of HMGB1 in lipopolysaccharide (LPS)-induced acute liver injuries need more investigation. EVs were identified by transmission electron microscopy, nanoparticle tracking analysis (NTA), and western blotting. The co-localization of HMGB1, RAGE (receptor for advanced glycation end-products), EEA1, Rab5, Rab7, Lamp1 and transferrin were detected by confocal microscopy. The interaction of HMGB1 and RAGE were investigated by co-immunoprecipitation. EVs were labeled with the PKH67 and used for uptake experiments. The pyroptotic cell death was determined by FLICA 660-YVAD-FMK. The expression of NLRP3 (NOD-like receptor family pyrin domain containing 3) inflammasomes were analyzed by western-blot or immunohistochemistry. Serum HMGB1, ALT (alanine aminotransferase), AST (aspartate aminotransferase), LDH (lactate dehydrogenase) and MPO (myeloperoxidase) were measured using a commercial kit. The extracellular vesicle HMGB1 was detected in the serums of sepsis patients. Macrophages were found to contribute to HMGB1 release through the EVs. HMGB1-RAGE interactions participated in the loading of HMGB1 into the EVs. These EVs shuttled HMGB1 to target cells by transferrin-mediated endocytosis leading to hepatocyte pyroptosis by the activation of NLRP3 inflammasomes. Moreover, a positive correlation was verified between the sepsis serum EVs-HMGB1 level and clinical liver damage. This finding provides insights for the development of novel diagnostic and therapeutic strategies for acute liver injuries.

3.
Cell Rep ; 37(5): 109943, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34731603

RESUMO

The ARID1A subunit of SWI/SNF chromatin remodeling complexes is a potent tumor suppressor. Here, a degron is applied to detect rapid loss of chromatin accessibility at thousands of loci where ARID1A acts to generate accessible minidomains of nucleosomes. Loss of ARID1A also results in the redistribution of the coactivator EP300. Co-incident EP300 dissociation and lost chromatin accessibility at enhancer elements are highly enriched adjacent to rapidly downregulated genes. In contrast, sites of gained EP300 occupancy are linked to genes that are transcriptionally upregulated. These chromatin changes are associated with a small number of genes that are differentially expressed in the first hours following loss of ARID1A. Indirect or adaptive changes dominate the transcriptome following growth for days after loss of ARID1A and result in strong engagement with cancer pathways. The identification of this hierarchy suggests sites for intervention in ARID1A-driven diseases.

4.
J Oral Pathol Med ; 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34797582

RESUMO

BACKGROUND: MicroRNAs (miRNAs) and mRNAs have been significantly implicated in tumorigenesis and served as promising prognostic biomarkers for human cancer. Hence, this study was aimed to develop the pivotal miRNA biomarkers-based prognostic signature for salivary adenoid cystic carcinoma (SACC). METHODS: The miRNA and mRNA expression data were integrated from the GEO database to study their involvement in SACC development and progression. GO(Gene Ontology) and KEGG(Kyoto Encyclopedia of Genes and Genomes) were conducted to analysis the biological pathways. RT-qPCR was used to verify the expression of selected miRNAs in SACC and corresponding normal tissues. RESULTS: There were 386 DEGs: 158 up-regulated and 228 down-regulated genes and 102 Dems: 78 up-regulated and 24 down-regulated miRNAs in the SACC samples. A miRNA-mRNA network containing 11 miRNAs and 199 DEGs was subsequently constructed. GO and KEGG enrichment analysis revealed that the genes targeted by the 11 miRNAs were mostly involved in tumor-related pathways and processes, such as miRNAs in cancer, focal adhesion, neurotrophin signalling pathway, and the PI3K-Akt signaling pathway. Among them, 4 miRNAs (miR-375, miR-494, miR-34c-5p and miR-331-3p) were selected to verify by RT-qPCR in 36 pairs of collected SACC and adjacent non-tumor samples. Overall survival (OS) analysis revealed that the higher expression of miR-331-3p was significantly associated with a worst overall survival and multivariate Cox regression analysis suggested that hsa-miR-331-3p could be an independent prognostic factor for SACC. CONCLUSION: Our results revealed that 4-miRNAs signature was a powerful prognostic biomarker for SACC, which provide a basis for exploring deeper mechanisms regarding the progression of SACC, and leading to the development of potential therapeutic strategies.

5.
J Environ Sci (China) ; 110: 21-27, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34593191

RESUMO

The redox state of arsenic controls its toxicity and mobility in the subsurface environment. Understanding the redox reactions of arsenic is particularly important for addressing its environmental behavior. Clay minerals are commonly found in soils and sediments, which are an important host for arsenic. However, limited information is known about the redox reactions between arsenic and structural Fe in clay minerals. In this study, the redox reactions between As(III)/As(V) and structural Fe in nontronite NAu-2 were investigated in anaerobic batch experiments. No oxidation of As(III) was observed by the native Fe(III)-NAu-2. Interestingly, anaerobic oxidation of As(III) to As(V) occurred after Fe(III)-NAu-2 was bioreduced. Furthermore, anaerobic oxidization of As(III) by bioreduced NAu-2 was significantly promoted by increasing Fe(III)-NAu-2 reduction extent and initial As(III) concentrations. Bioreduction of Fe(III)-NAu-2 generated reactive Fe(III)-O-Fe(II) moieties at clay mineral edge sites. Anaerobic oxidation of As(III) was attributed to the strong oxidation activity of the structural Fe(III) within the Fe(III)-O-Fe(II) moieties. Our results provide a potential explanation for the presence of As(V) in the anaerobic subsurface environment. Our findings also highlight that clay minerals can play an important role in controlling the redox state of arsenic in the natural environment.


Assuntos
Arsênio , Arsenitos , Anaerobiose , Compostos Férricos , Ferro , Minerais , Oxirredução
6.
PeerJ ; 9: e12174, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34616623

RESUMO

The CYP75 gene family plays an important role in flavonoid biosynthesis in plants. Little is known about the evolution of the gene family within the grape family. Here, we extracted the CYP75 genes from transcriptome data of 15 grape species and 36 representative genomes from other plants to explore the evolutionary history of the CYP75 gene family in Vitaceae. The structure of the CYP75 protein sequences is highly conserved with the variation mainly occurring in the N terminal and the middle region. The evolutionary analyses suggested classifying the CYP75 gene family into three groups in Vitaceae, namely Vitaceae A1, Vitaceae A2 and Vitaceae B. The Vitaceae A1 and A2 belong to the CYP75A subfamily and the Vitaceae B belongs to the CYP75B subfamily. Within the Vitaceae A1, most Vitaceae taxa present only one copy of the CYP75A protein sequence except for Vitis vinifera with a high number of sequences, which might have originated through recent gene duplications after its split from the other species. Vitaceae A2 contain only CYP75A sequences from Vitaceae sister to one from Camellia sinensis, probably representing a relict lineage. The CYP75B proteins were found to be dominated in Vitaceae and other angiosperms. Our results provide important insights into understanding the evolutionary history of the CYP75 gene family in Vitaceae and other angiosperms.

7.
J Exp Bot ; 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34610119

RESUMO

Rice polluted by metal(loid)s, especially arsenic (As) and cadmium (Cd), imposes serious health risks. Numerous studies have demonstrated that the obligate plant symbionts arbuscular mycorrhizal fungi (AMF) can reduce As and Cd concentrations in rice. The behaviours of metal(loid)s in the soil-rice-AMF system are of significant interest for scientists in the fields of plant biology, microbiology, agriculture, and environmental science. This paper reviews the mechanisms of As and Cd accumulation in rice with and without the involvement of AMF. In the context of the rice-soil-AMF system, we review and discuss the role of AMF in affecting soil ion mobility, chemical form, transport pathways (including symplast and apoplast), and genotype variation. A potential strategy for AMF application in rice fields is considered, followed by future research directions to improve theoretical understanding and encourage field application.

8.
BMC Gastroenterol ; 21(1): 367, 2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34627159

RESUMO

BACKGROUND: The clinical features of amoebic colitis resemble those of inflammatory bowel disease (IBD), and therefore the risk of misdiagnosis is very high. The aim of this study was to analyse the characteristics of the endoscopic and pathological findings of amebic colitis and the lessons from our patients, which were useful for diagnosing the amebic colitis timely and avoiding the serious complication. METHODS: We retrospectively reviewed data of all amebic colitis admitted to Beijing Friendship Hospital from January 2015 to January 2020. Cases were diagnosed by clinical presentation, laboratory examinations, and colonoscopy with biopsy and histological examination, no ELISA stool antigen or PCR tests were used. RESULTS: 16 patients were diagnosed with amebic colitis by the colonoscopy accompanied by biopsy and microscopic examination. At first time, 12 (75%) patients were misdiagnosed as IBD. Cecum was the most common site of amebic colitis (100%), and the caecum and rectum were also involved in many lesions (68.75%). Multiple lesions of erosion and/or ulcer were recognized in all patients (100%).The endoscopic findings included multiple irregular shaped ulcers and erosions with surrounding erythema, and the ulcers and erosions were covered by the white or yellow exudates. The intervening mucosae between the ulcers or erosions were normal. The features of rectums can be divided to 2 types: in 6 patients (54.5%), the irregular ulcer or erosions covered with white or yellow exudates were observed in rectum and cecum, and the bloody exudates in rectum were more severe than those in cecum; in other 5 patients (45.5%), rectal lesions were much less severe than those in cecum, the small superficial erosion or reddened mucosa were observed in the rectal ampulla. All patients were diagnosed as detection of amebic trophozoites from HE-stained biopsy specimens. The number of trophozoites ranged from 1/HPF to > 50/HPF. Among 16 cases, mild architectural alteration of colon crypt were observed in 10 cases (62.5%), and serious architectural alteration of colon crypt was found which had crypt branch in 1 case (16.7%). Cryptitis was observed in 12 cases (75%) and its severity was mild or moderate. No crypts abscess was observed in all cases. CONCLUSIONS: The colonoscopy with histological examination are very important to diagnose the amebic colitis. Detect the amoebic trophozoites in the exudates by histological examination is the vital. Sometimes a negative biopsy does not rule out amebiasis, repeated biopsies may be needed to make the diagnosis.


Assuntos
Disenteria Amebiana , Doenças Inflamatórias Intestinais , Colonoscopia , Diagnóstico Diferencial , Disenteria Amebiana/diagnóstico , Humanos , Doenças Inflamatórias Intestinais/diagnóstico , Estudos Retrospectivos
9.
J Am Chem Soc ; 143(41): 17079-17089, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34610744

RESUMO

In parallel with advances in the synthesis of solid-state ionic conductors, there is a need to understand the underlying mechanisms behind their improved ionic conductivities. This can be achieved by obtaining an atomic level picture of the interplay between the structure of materials and the resultant ionic diffusion processes. To this end, the structure and dynamics of Mg2+-stabilized rotor phase material γ-Na3PO4, characterized by neutron scattering, are detailed in this work. The Mg2+-stabilized rotor phase is found to be thermally stable from 4 to 650 K. However, signatures of orientational disorder of the phosphate anions are also evident in the average structure. Long-range Na+ self-diffusion was probed by quasi-elastic neutron scattering and subsequently modeled via a jump diffusion matrix with consideration of the phosphate anion rotations. The resultant diffusion model points directly to coupled anion-cation dynamics. Our approach highlights the importance of considering the whole system when developing an atomic level picture of structure and dynamics, which is critical in the rational design and optimization of energy materials.

10.
J Inflamm Res ; 14: 5079-5094, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34675589

RESUMO

Background: Acute lung injury (ALI) is a severe respiratory disease with high rates of morbidity and mortality. Many mediators regarding endogenous or exogenous are involved in the pathophysiology of ALI. Here, we have uncovered the involvement of integrins and matrix metalloproteinases, as critical determinants of excessive inflammation and endothelial permeability, in the regulation of ALI. Methods: Inflammatory cytokines were measured by quantitative real-time PCR for mRNA levels and ELISA for secretion levels. Endothelial permeability assay was detected by the passage of rhodamine B isothiocyanate-dextran. Mice lung permeability was assayed by Evans blue albumin (EBA). Western blot was used for protein level measurements. The intracellular reactive oxygen species (ROS) were evaluated using a cell-permeable probe, DCFH-DA. Intratracheal injection of lipopolysaccharide (LPS) into mice was conducted to establish the lung injury model. Results: Exogenous MMP-9 significantly aggravated the inflammatory response and permeability in mouse pulmonary microvascular endothelial cells (PMVECs) treated by LPS, whereas knockdown of MMP-9 exhibited the opposite phenotypes. Knockdown of integrin ß3 or ß5 in LPS-treated PMVECs significantly downregulated MMP-9 expression and decreased inflammatory response and permeability in the presence or absence of exogenous MMP-9. Additionally, the interaction of MMP-9 and integrin ß5 was impaired by a ROS scavenger, which further decreased the pro-inflammatory cytokines production and endothelial leakage in PMVECs subjected to co-treatment (LPS with exogenous MMP-9). In vivo studies, exogenous MMP-9 treatment or knockdown ß3 integrin significantly decreased survival in ALI mice. Notably, knockdown of ß5 integrin alone had no remarkable effect on survival, but which combined with anti-MMP-9 treatment significantly improved the survival by ameliorating excessive lung inflammation and permeability in ALI mice. Conclusion: These findings support the ß3/5 integrin-MMP-9 axis as an endogenous signal that could play a pivotal role in regulating inflammatory response and alveolar-capillary permeability in ALI.

11.
Cancer Manag Res ; 13: 7637-7644, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34675659

RESUMO

Objective: Cancer is well known as the most important risk factor for the emergence of pulmonary embolism (PE). The incidence of incidental PE (IPE) has increased with widely use of multi-detector-row computed tomography (CT) technology. Simultaneously, more new cancer patients diagnosed concomitantly with IPE are found. No study has examined the presentation and prognosis of incidental pulmonary embolism (IPE) in gastric cancer patients. The aim of this study was to analyse prognostic factors in patients with advanced gastric cancer complicated with IPE. Patients and Methods: Ninety patients with histologically confirmed advanced gastric adenocarcinoma diagnosed with IPE were enrolled. Continuous variables were compared using Student's t-test or the Mann-Whitney U-test if non-normally distributed. The Chi-squared test (or Fisher's exact test where appropriate) was used to compare categorical variables. The Kaplan-Meier method and the Log rank test were used for survival analysis. Independent prognostic factors for survival were determined using a Cox proportional hazards model. A two-sided P-value < 0.05 was considered statistically significant. Results: Nineteen patients were diagnosed with IPE concomitantly with gastric cancer. Concurrence of gastric cancer and IPE, lack of anticoagulation therapy, and location of IPE were associated with survival. After adjusting for age and sex, the concurrence of gastric cancer and IPE, lack of anticoagulation, and central IPE independently influenced the survival of advanced gastric cancer patients with IPE. Subgroup analysis of patients with peripheral pulmonary embolisms confirmed that anticoagulant therapy provided a survival benefit. Conclusion: Concurrence of gastric cancer and IPE may be a prognostic factor for advanced gastric cancer patients with IPE.

12.
Pain Physician ; 24(7): E1099-E1108, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34704719

RESUMO

BACKGROUND: Postoperative pain management has increasingly become a public health problem worldwide. Psychological factors can be considered as independent risk factors for the intensity of postoperative pain and the occurrence of postoperative chronic pain. OBJECTIVES: As stress events could facilitate NLR family pyrin domain-containing 3 (NLRP3) inflammasome activation in the central nervous system, we aimed to explore the role of perioperative NLRP3-mediated neuroinflammation in the exacerbation of incisional hyperalgesia in stressed rats. STUDY DESIGN: Experimental trial in rats. SETTING: Department of Anesthesiology, Shanghai, China. METHODS: All animal experimental procedures were approved by the Animal Care and Use Committee of Shanghai Jiaotong University School of Medicine. This study was conducted in rat models of chronic restraint stress and hind paw incision model. Serum corticosterone level measurement and emotion-related behavioral tests were used to confirm that chronic restraint stress can cause depression-like behavior in rats. Pain behavior after surgery was assessed by withdrawal response to von Frey filament application. Immunofluorescence staining and  the Western blot test were used to evaluate the protein level of NLRP3, IL-1beta, C-fos in the basolateral amygdala (BLA) and GluN2B-containing N-methyl-D-aspartate (NMDA) receptors (GluN2B) expression in the central nucleus of the amygdala (CeA), respectively. Intra-BLA cannulation and microinjection of an NLRP3 specific inhibitor--MCC950 (0.5 µL, 2 µg/µL) were applied to the stressed rats for 4 days perioperatively to explore whether the stress-induced postoperative hyperalgesia and GluN2B expression in CeA can be altered. RESULTS: The results showed that chronic restraint stress exposure led to depressive behavior in rats. Moreover, chronic restraint stress exposure increased NLRP3 and interleukin 1 beta (IL-1beta) expression in the basolateral amygdala (BLA), as well as exacerbated postoperative hyperalgesia and prolonged the recovery time of postoperative pain. Meanwhile, GluN2B expression in the CeA of the stressed group was higher than that of the control incision group. Inhibition of NLRP3 reversed the exacerbation of postoperative hyperalgesia by stress exposure, and down-regulated GluN2B expression in the CeA. LIMITATIONS: The upstream mechanism by which NLRP3 is elevated in stressed rats was not explored. CONCLUSION: These findings suggest that chronic restraint stress may influence postoperative hyperalgesia and NLRP3-mediated neuroinflammation, which may in turn contribute to stress-induced postoperative pain exacerbation.

13.
J Neurooncol ; 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34661791

RESUMO

INTRODUCTION: Despite manifold advances in oncology, cancers of the central nervous system remain among the most lethal. Unique features of the brain, including distinct cellular composition, immunological privilege, and physical barriers to therapeutic delivery, likely contribute to the poor prognosis of patients with neuro-oncological disease. Focused ultrasound is an emerging technology that allows transcranial delivery of ultrasound energy to focal brain targets with great precision. METHODS: A review of the clinical and preclinical focused ultrasound literature was performed to obtain data regarding the current state of the focused ultrasound in context of neuro-oncology. A narrative review was then constructed to provide an overview of current and future applications of this technology. RESULTS: Focused ultrasound can facilitate direct control of tumors by thermal or mechanical ablation, as well as enhance delivery of diverse therapeutics by disruption of the blood-brain barrier without local tissue damage. Indeed, ultrasound-sensitive drug formulations or sonosensitizers may be combined with ultrasound blood-brain barrier disruption to achieve high local drug concentration while limiting systemic exposure to therapeutics. Furthermore, focused ultrasound can induce radiosensitization, immunomodulation, and neuromodulation. Here we review applications of focused ultrasound with a focus on approaches currently under clinical investigation for the treatment of neuro-oncological disease, such as blood-brain barrier disruption for drug delivery and thermal ablation. We also discuss design of clinical trials, selection of patient cohorts, and emerging approaches to improve the efficacy of transcranial ultrasound, such as histotripsy, as well as combinatorial strategies to exploit synergistic biological effects of existing cancer therapies and ultrasound. CONCLUSIONS: Focused ultrasound is a promising and actively expanding therapeutic modality for diverse neuro-oncological diseases.

15.
Artigo em Inglês | MEDLINE | ID: mdl-34655890

RESUMO

Bufei-Huoxue Capsule (BFHX) was applied to treat chronic obstructive pulmonary disease (COPD) in China. It is composed of Astragali Radix, Paeoniae Radix Rubra, and Psoralea Fructus. A sensitive and reliable ultra-high-performance liquid chromatography-mass spectrometry (UHPLC-MS/MS) method was developed and validated to quantify the eight main bioactive compounds (psoralen, isopsoralen, neobabaisoflavone, corylin, bavachin, astragaloside IV, ononin and formononetin) in rat plasma after oral administration of BFHX. Osthol was used as an internal standard (IS). Plasma samples were pretreated with methanol to precipitate protein. Chromatographic separation was accomplished using Hypersil GOLDTM C18 column (2.1 mm × 100 mm, 1.9 µm) with a gradient elution profile and a mobile phase consisting of (A) 0.1% formic acid in water and (B) acetonitrile and the flow rate was set at 0.2 mL/min. Multiple reaction monitoring (MRM) mode was applied to perform mass spectrometric analyses. All calibration curves were linear (r > 0.9908) in tested ranges. The intra- and inter-day accuracy and precisions of eight compounds at three different concentration levels were within the acceptable limits. The extraction recovery was within the range of 76.4 âˆ¼ 105.2% and the matrix effects were within the range of 88.3 âˆ¼ 115.0% (RSD ≤ 15.6%). The dilution effects were within the range of 90.2 âˆ¼ 114.9%. These 8 compounds were stable under the tested conditions. So the developed method was valid to evaluate the pharmacokinetic study of eight bioactive compounds after oral administration of BFHX.

16.
Plant Cell ; 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34718767

RESUMO

Stomatal pores and the leaf cuticle regulate evaporation from the plant body and balance the trade-off between photosynthesis and water loss. MYB16, encoding a transcription factor involved in cutin biosynthesis, is expressed in stomatal lineage ground cells, suggesting a link between cutin biosynthesis and stomatal development. Here, we show that the downregulation of MYB16 in meristemoids is directly mediated by the stomatal master transcription factor SPEECHLESS (SPCH) in Arabidopsis thaliana. The suppression of MYB16 before an asymmetric division is crucial for stomatal patterning, as its overexpression or ectopic expression in meristemoids increased stomatal density and resulted in the formation of stomatal clusters, as well as affecting the outer cell wall structure. Expressing a cutinase gene in plants ectopically expressing MYB16 reduced stomatal clustering, suggesting that cutin affects stomatal signaling or the polarity setup in asymmetrically dividing cells. The clustered stomatal phenotype was rescued by overexpressing EPIDERMAL PATTERNING FACTOR2, suggesting that stomatal signaling was still functional in these plants. Growing seedlings ectopically expressing MYB16 on high-percentage agar plates to modulate tensile strength rescued the polarity and stomatal cluster defects of these seedlings. Therefore, the inhibition of MYB16 expression by SPCH in the early stomatal lineage is required to correctly place the polarity protein needed for stomatal patterning during leaf morphogenesis.

18.
Eur J Pediatr ; 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34535829

RESUMO

Many epidemiological studies have assessed the association between maternal antibiotic exposure during pregnancy and childhood acute lymphoblastic leukemia (ALL), while reaching inconsistent conclusions. In order to clarify the association, the publications in English that provided information about maternal antibiotic exposure during pregnancy and ALL risk in offspring in the PubMed, Embase, and Web of Science databases were systematically reviewed and we performed a meta-analysis using the random-effect models. Results of pooled analysis showed that maternal antibiotic intake during pregnancy is not associated with childhood ALL risk (pooled odds ratio 1.07, 95% confidence interval 0.98-1.18) without significant heterogeneity (I2 = 13.7%, P = 0.310). This finding was consistent across subgroups stratified by type of study design, measurement method, sample size, study quality, and pregnancy stage. Our findings suggest that maternal antibiotic consumption during pregnancy was not associated with ALL risk in progeny. Further investigations are needed to confirm the results and assess any risk differences of ALL by types of antibiotics.Conclusions: Our findings suggest that maternal antibiotics consumption during pregnancy was not associated with ALL risk in progeny. Further investigations are needed to confirm the results and assess any risk differences of ALL by types of antibiotics. What is Known: • It is not unusual for pregnant woman to receive antibiotics for local or systematic use during pregnancy. • The conclusions regarding the associations between maternal antibiotics use during pregnancy and childhood ALL risk were inconsistent. What is New: • Maternal antibiotics consumption during pregnancy was not associated with the increased ALL risk in offspring. • Further laboratory evidences are needed to confirm the results.

19.
Plant Biotechnol J ; 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34490975

RESUMO

The medicinal plant Scutellaria baicalensis Georgi is rich in specialized 4'-deoxyflavones, which are reported to have many health-promoting properties. We assayed Scutellaria flavones with different methoxyl groups on human cancer cell lines and found that polymethoxylated 4'-deoxyflavones, like skullcapflavone I and tenaxin I have stronger ability to induce apoptosis compared to unmethylated baicalein, showing that methoxylation enhances bioactivity as well as the physical properties of specialized flavones, while having no side-effects on healthy cells. We investigated the formation of methoxylated flavones and found that two O-methyltransferase (OMT) families are active in the roots of S. baicalensis. The Type II OMTs, SbPFOMT2 and SbPFOMT5, decorate one of two adjacent hydroxyl groups on flavones and are responsible for methylation on the C6, 8 and 3'-hydroxyl positions, to form oroxylin A, tenaxin II and chrysoeriol respectively. The Type I OMTs, SbFOMT3, SbFOMT5 and SbFOMT6 account mainly for C7-methoxylation of flavones, but SbFOMT5 can also methylate baicalein on its C5 and C6-hydroxyl positions. The dimethoxylated flavone, skullcapflavone I (found naturally in roots of S. baicalensis) can be produced in yeast by co-expressing SbPFOMT5 plus SbFOMT6 when the appropriately hydroxylated 4'-deoxyflavone substrates are supplied in the medium. Co-expression of SbPFOMT5 plus SbFOMT5 in yeast produced tenaxin I, also found in Scutellaria roots. This work showed that both type I and type II OMT enzymes are involved in biosynthesis of methoxylated flavones in S. baicalensis.

20.
J Hazard Mater ; 416: 125894, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492832

RESUMO

The chemistry of root cell wall of rice could be changed by inoculation of arbuscular mycorrhizal fungi (AMF). Hydroponic experiments were conducted to investigate the roles of such changes on cadmium (Cd) uptake and distribution in rice. Results showed that inoculation of AM fungus Rhizophagus intraradices (RI) significantly enhanced (p < 0.05) shoot biomass, plant height and root length of rice, and decreased Cd concentration in shoot and root under Cd stress. Moreover, Cd in root was mainly found in pectin and hemicellulose 1 (HC1) components of root cell wall. Inoculation of RI increased the levels of pectin, HC1 and lignin content, accompanied by the increments of L-phenylalanine ammonia-lyase (PAL) and pectin methylesterase (PME) activities. Results of Fourier transform infrared spectroscopy further showed that more hydroxyl and carboxyl groups in root cell wall were observed in mycorrhizal treatment, compared with control. This study demonstrates that cell wall components could be the locations for Cd fixation, which reduced Cd transportation from root to shoot. Inoculation of AMF may remodel root cell wall biosynthesis and affect the characteristics of Cd fixation. The entering and fixing mechanisms should be further studied.


Assuntos
Micorrizas , Oryza , Poluentes do Solo , Cádmio/análise , Parede Celular/química , Fungos , Raízes de Plantas/química , Poluentes do Solo/análise
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