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1.
EMBO J ; 40(11): e106771, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33909912

RESUMO

Chemical compounds have recently been introduced as alternative and non-integrating inducers of pluripotent stem cell fate. However, chemical reprogramming is hampered by low efficiency and the molecular mechanisms remain poorly characterized. Here, we show that inhibition of spleen tyrosine kinase (Syk) by R406 significantly promotes mouse chemical reprogramming. Mechanistically, R406 alleviates Syk / calcineurin (Cn) / nuclear factor of activated T cells (NFAT) signaling-mediated suppression of glycine, serine, and threonine metabolic genes and dependent metabolites. Syk inhibition upregulates glycine level and downstream transsulfuration cysteine biosynthesis, promoting cysteine metabolism and cellular hydrogen sulfide (H2 S) production. This metabolic rewiring decreased oxidative phosphorylation and ROS levels, enhancing chemical reprogramming. In sum, our study identifies Syk-Cn-NFAT signaling axis as a new barrier of chemical reprogramming and suggests metabolic rewiring and redox homeostasis as important opportunities for controlling cell fates.


Assuntos
Fibroblastos/metabolismo , Sulfeto de Hidrogênio/metabolismo , Quinase Syk/antagonistas & inibidores , Animais , Calcineurina/metabolismo , Células Cultivadas , Cisteína/metabolismo , Fibroblastos/efeitos dos fármacos , Glicina/metabolismo , Camundongos , Fatores de Transcrição NFATC/metabolismo , Oxazinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
2.
Anal Chem ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38934225

RESUMO

Lumpy skin disease virus (LSDV) is a severe and highly contagious form of cowpox. As LSDV continues to mutate and there is no vaccine and treatment in nonendemic countries, early detection of LSDV becomes an important basis for epidemic prevention and control, especially for detection of conserved sequences. A new label-free and sensitive fluorescence method was developed based on a light-up RNA aptamer for detecting LSDV. The method integrated recombinase polymerase amplification (RPA), CRISPR/Cas12a, 10-23 DNAzyme, and Baby Spinach RNA aptamer for triple cascade signal amplification. Based on highly sensitive and specific RPA and CRISPR/Cas12a, DNAzyme achieved a third signal amplification. Additionally, the Baby Spinach RNA aptamer had stronger fluorescence signals and higher quantum yields. The label-free method had ultrahigh sensitivity with the actual detection limit as 1.29 copies·µL-1. The method was 100-fold more sensitive compared to RPA with Cas12a. Moreover, it had no cross-reactivity with viruses belonging to the Capripoxvirus, such as sheep pox virus and goat pox virus with genetic homology as 97%. Furthermore, the method displayed 100% accuracy in 50 actual samples. Therefore, the method based on RPA, Cas12a, and 10-23 DNAzyme had advantages in LSDV detection and provided a new solution for LSD prevention and control.

3.
Drug Chem Toxicol ; : 1-15, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38465444

RESUMO

Alkaloids are naturally occurring compounds with complex structures found in natural plants. To further improve the understanding of plant alkaloids, this review focuses on the classification, toxicity and mechanisms of action, providing insight into the occurrence of alkaloid-poisoning events and guiding the safe use of alkaloids in food, supplements and clinical applications. Based on their chemical structure, alkaloids can be divided into organic amines, diterpenoids, pyridines, isoquinolines, indoles, pyrrolidines, steroids, imidazoles and purines. The mechanisms of toxicity of alkaloids, including neurotoxicity, hepatoxicity, nephrotoxicity, cardiotoxicity and cytotoxicity, have also been reviewed. Some cases of alkaloid poisoning have been introduced when used as food or clinically, including accidental food poisoning, excessive consumption, and poisoning caused by the improper use of alkaloids in a clinical setting, and the importance of safety evaluation was illustrated. This review summarizes the toxicity and mechanism of action of alkaloids and provides evidence for the need for the safe use of alkaloids in food, supplements and clinical applications.

4.
BMC Pregnancy Childbirth ; 23(1): 102, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36755227

RESUMO

BACKGROUND: A growing number of cytogenetic techniques have been used for prenatal diagnosis. This study aimed to demonstrate the usefulness of karyotyping, BACs-on-Beads (BoBs) assay and single nucleotide polymorphism (SNP) array in prenatal diagnosis during the second trimester based on our laboratory experience. METHODS: A total of 10,580 pregnant women with a variety of indications for amniocentesis were enrolled in this retrospective study between January 2015 and December 2020, of whom amniotic fluid samples were analysed in 10,320 women. The main technical indicators of participants in the three different technologies were summarized, and cases of chromosome abnormalities were further evaluated. RESULTS: The overall abnormality detection rate of karyotyping among all the amniotic fluid samples was 15.4%, and trisomy 21 was the most common abnormality (20.9%). The total abnormality detection rate of the BoBs assay was 5.6%, and the diagnosis rate of microdeletion/microduplication syndromes that were not identified by karyotyping was 0.2%. The detection results of the BoBs assay were 100.0% concordant with karyotyping analysis in common aneuploidies. Seventy (87.5%) cases of structural abnormalities were missed by BoBs assay. The total abnormality detection rate of the SNP array was 21.6%. The detection results of common aneuploidies were exactly the same between SNP array and karyotyping. Overall, 60.1% of structural abnormalities were missed by SNP array. The further detection rate of pathogenic significant copy number variations (CNVs) by SNP was 1.4%. CONCLUSIONS: Karyotyping analysis combined with BoBs assay or SNP array for prenatal diagnosis could provide quick and accurate results. Combined use of the technologies, especially with SNP array, improved the diagnostic yield and interpretation of the results, which contributes to genetic counselling. BoBs assay or SNP array could be a useful supplement to karyotyping.


Assuntos
Transtornos Cromossômicos , Feminino , Gravidez , Humanos , Transtornos Cromossômicos/diagnóstico , Líquido Amniótico , Variações do Número de Cópias de DNA , Estudos Retrospectivos , Diagnóstico Pré-Natal/métodos , Aneuploidia
5.
J Appl Toxicol ; 43(3): 338-349, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36148542

RESUMO

Over the years, the safety of traditional Chinese medicine (TCM) has received widespread attention, especially the central nervous system-related adverse reactions. Indeed, the complexity of TCM has limited the widespread application of TCM. The article summarizes the main components associated with neurotoxicity, including alkaloids, terpenes, flavonoids, saponins, proteins, and heavy metals, by reviewing the literature on the neurotoxicity of TCM. It has been established that the neurotoxicity mechanisms mainly include mitochondrial damage, oxidative damage, inhibition of cell proliferation (including transcriptional and DNA damage), changes in cell membrane permeability, and apoptosis. By reviewing the latest literature, this paper provides the foothold for follow-up studies and can assist clinicians in preventing neurotoxicity via rational and safe TCM drug use.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Medicamentos de Ervas Chinesas/toxicidade , Dano ao DNA , Sistema Nervoso Central , Flavonoides
6.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 40(6): 727-732, 2023 Jun 10.
Artigo em Zh | MEDLINE | ID: mdl-37212011

RESUMO

OBJECTIVE: To carry out optical genome mapping (OGM) for a Chinese pedigree with a rare paracentric reverse insertion of chromosome 17. METHODS: A high-risk pregnant woman identified at the Prenatal Diagnosis Center of Hangzhou Women's Hospital in October 2021 and her family members were selected as the study subjects. Chromosome G banding analysis, fluorescence in situ hybridization (FISH), single nucleotide polymorphism array (SNP array) and OGM were applied to verify the balanced structural abnormality of chromosome 17 in the pedigree. RESULTS: Chromosomal karyotyping analysis and SNP array assay have identified a duplication of 17q23q25 in the fetus. Karyotyping analysis of the pregnant woman showed that the structure of chromosome 17 was abnormal, whilst SNP array has detected no abnormality. OGM revealed that the woman has carried a paracentric reverse insertion, which was confirmed by FISH. The karyotype of her husband was normal. CONCLUSION: The duplication of 17q23q25 in the fetus has derived from a paracentric reverse insertion of chromosome 17 in its mother. OGM has the advantage for delineating balanced chromosome structural abnormalities.


Assuntos
Cromossomos Humanos Par 17 , População do Leste Asiático , Gravidez , Humanos , Feminino , Linhagem , Hibridização in Situ Fluorescente , Cromossomos Humanos Par 17/genética , Aberrações Cromossômicas , Diagnóstico Pré-Natal , Mapeamento Cromossômico , Inversão Cromossômica
7.
J Cell Mol Med ; 26(8): 2322-2336, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35277915

RESUMO

Pancreatic cancer (PC) is one of the most lethal types of cancer due to its asymptomatic nature in the early stages and consequent late diagnosis. Its mortality rate remains high despite advances in treatment strategies, which include a combination of surgical resection and adjuvant therapy. Although these approaches may have a positive effect on prognosis, the development of chemo- and radioresistance still poses a significant challenge for successful PC treatment. Heterogeneous nuclear ribonucleoprotein C1/C2 (HNRNPC) and RhoA have been implicated in the regulation of tumour cell proliferation and chemo- and radioresistance. Our study aims to investigate the mechanism for HNRNPC regulation of PC radiation resistance via the RhoA pathway. We found that HNRNPC and RhoA mRNA and protein expression levels were significantly higher in PC tissues compared to adjacent non-tumour tissue. Furthermore, high HNRNPC expression was associated with poor patient prognosis. Using HNRNPC overexpression and siRNA interference, we demonstrated that HNRNPC overexpression promoted radiation resistance in PC cells, while HNRNPC knockdown increased radiosensitivity. However, silencing of RhoA expression was shown to attenuate radiation resistance caused by HNRNPC overexpression. Next, we identified RhoA as a downstream target of HNRNPC and showed that inhibition of the RhoA/ROCK2-YAP/TAZ pathway led to a reduction in DNA damage repair and radiation resistance. Finally, using both in vitro assays and an in vivo subcutaneous tumour xenograft model, we demonstrated that RhoA inhibition can hinder the activity of cancer-related fibroblasts and weaken PC radiation resistance. Our study describes a role for HNRNPC and the RhoA/ROCK2-YAP/TAZ signalling pathways in mediating radiation resistance and provides a potential therapeutic target for improving the treatment of PC.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias Pancreáticas , Fibroblastos Associados a Câncer/metabolismo , Linhagem Celular Tumoral , Dano ao DNA , Ribonucleoproteínas Nucleares Heterogêneas Grupo C/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo C/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/radioterapia , Tolerância a Radiação/genética , Proteína rhoA de Ligação ao GTP/genética , Proteína rhoA de Ligação ao GTP/metabolismo , Neoplasias Pancreáticas
8.
Hum Mol Genet ; 29(1): 149-158, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31814020

RESUMO

5-Methylcytosine (5mC), generated through the covalent addition of a methyl group to the fifth carbon of cytosine, is the most prevalent DNA modification in humans and functions as a critical player in the regulation of tissue and cell-specific gene expression. 5mC can be oxidized to 5-hydroxymethylcytosine (5hmC) by ten-eleven translocation (TET) enzymes, which is enriched in brain. Alzheimer's disease (AD) is the most common neurodegenerative disorder, and several studies using the samples collected from Caucasian cohorts have found that epigenetics, particularly cytosine methylation, could play a role in the etiological process of AD. However, little research has been conducted using the samples of other ethnic groups. Here we generated genome-wide profiles of both 5mC and 5hmC in human frontal cortex tissues from late-onset Chinese AD patients and cognitively normal controls. We identified both Chinese-specific and overlapping differentially hydroxymethylated regions (DhMRs) with Caucasian cohorts. Pathway analyses revealed specific pathways enriched among Chinese-specific DhMRs, as well as the shared DhMRs with Caucasian cohorts. Furthermore, two important transcription factor-binding motifs, hypoxia-inducible factor 2α (HIF2α) and hypoxia-inducible factor 1α (HIF1α), were enriched in the DhMRs. Our analyses provide the first genome-wide profiling of DNA hydroxymethylation of the frontal cortex of AD patients from China, emphasizing an important role of 5hmC in AD pathogenesis and highlighting both ethnicity-specific and overlapping changes of brain hydroxymethylome in AD.


Assuntos
Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , 5-Metilcitosina/análogos & derivados , 5-Metilcitosina/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Encéfalo/patologia , Biologia Computacional , Metilação de DNA/genética , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , RNA-Seq
9.
Int Ophthalmol ; 42(8): 2459-2472, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35192105

RESUMO

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


Assuntos
Síndromes do Olho Seco , Fator de Necrose Tumoral alfa , Método Duplo-Cego , Síndromes do Olho Seco/diagnóstico , Síndromes do Olho Seco/tratamento farmacológico , Fluoresceína , Humanos , Imunossupressores/uso terapêutico , Soluções Oftálmicas/uso terapêutico , Lágrimas , Resultado do Tratamento , Inibidores do Fator de Necrose Tumoral
10.
Cancer Cell Int ; 21(1): 57, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33461544

RESUMO

BACKGROUND: Drug resistance and metastasis involving hypoxic tumor environments and persistent stem cell populations are detrimental to the survival of patients with non-small cell lung carcinoma (NSCLC). Tie1 is upregulated in hypoxia and is believed to counteract the effectiveness of platinum agents by promoting the stemness properties in cells. We have investigated the association of Tie1 with HIF-1α and cisplatin resistance in NSCLC cell lines. METHODS: The expression of Tie1 in a pulmonary microvascular endothelial cell line (HPMEC) and NSCLC cell lines was detected using qRT-PCR and western blotting. The effect of Tie1 on cell stemness and migration was examined by sphere-forming and transwell assays in NSCLC cells with Tie1 silenced. The regulation of Tie1 by HIF-1α was evaluated by a dual-luciferase reporter assay and chromatin immunoprecipitation. RESULTS: We found that hypoxia could induce stemness and cisplatin resistance in vitro. Tie1 was expressed at low levels in NSCLC cells when compared with human pulmonary microvascular endothelial cells, however, its expression was increased by hypoxia. Additionally, Tie1 knockdown could reduce stemness properties and increase sensitivity to cisplatin in vitro and in a xenograft mouse model. The promoter of Tie1 contains two predicted hypoxia-response elements (HREs). We mutated both HRE sites and conducted chromatin immune-precipitation and promoter luciferase reporter assays and were able to conclude that the induction of Tie1 by hypoxia was HIF-1α-dependent. CONCLUSIONS: Our findings indicated that Tie1 is upregulated in a hypoxic environment by HIF-1α and contributes to tumorigenesis and cisplatin resistance through the promotion of stemness in NSCLC cells.

11.
Brain ; 143(7): 2220-2234, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32613234

RESUMO

This study aimed to determine the mutational spectrum of familial Parkinson's disease and sporadic early-onset Parkinson's disease (sEOPD) in a mainland Chinese population and the clinical features of mutation carriers. We performed multiplex ligation-dependent probe amplification assays and whole-exome sequencing for 1676 unrelated patients with Parkinson's disease in a mainland Chinese population, including 192 probands from families with autosomal-recessive Parkinson's disease, 242 probands from families with autosomal-dominant Parkinson's disease, and 1242 sEOPD patients (age at onset ≤ 50). According to standards and guidelines from the American College of Medical Genetics and Genomics, pathogenic/likely pathogenic variants in 23 known Parkinson's disease-associated genes occurred more frequently in the autosomal-recessive Parkinson's disease cohort (65 of 192, 33.85%) than in the autosomal-dominant Parkinson's disease cohort (10 of 242, 4.13%) and the sEOPD cohort (57 of 1242, 4.59%), which leads to an overall molecular diagnostic yield of 7.88% (132 of 1676). We found that PRKN was the most frequently mutated gene (n = 83, 4.95%) and present the first evidence of an SNCA duplication and LRRK2 p.N1437D variant in mainland China. In addition, several novel pathogenic/likely pathogenic variants including LRRK2 (p.V1447M and p.Y1645S), ATP13A2 (p.R735X and p.A819D), FBXO7 (p.G67E), LRP10 (c.322dupC/p.G109Rfs*51) and TMEM230 (c.429delT/p.P144Qfs*2) were identified in our cohort. Furthermore, the age at onset of the 132 probands with genetic diagnoses (median, 31.5 years) was about 14.5 years earlier than that of patients without molecular diagnoses (i.e. non-carriers, median 46.0 years). Specifically, the age at onset of Parkinson's disease patients with pathogenic/likely pathogenic variants in ATP13A2, PLA2G6, PRKN, or PINK1 was significantly lower than that of non-carriers, while the age at onset of carriers with other gene pathogenic/likely pathogenic variants was similar to that of non-carriers. The clinical spectrum of Parkinson's disease-associated gene carriers in this mainland Chinese population was similar to that of other populations. We also detected 61 probands with GBA possibly pathogenic variants (3.64%) and 59 probands with GBA p.L444P (3.52%). These results shed insight into the genetic spectrum and clinical manifestations of Parkinson's disease in mainland China and expand the existing repertoire of pathogenic or likely pathogenic variants involved in known Parkinson's disease-associated genes. Our data highlight the importance of genetic testing in Parkinson's disease patients with age at onset < 40 years, especially in those from families with a recessive inheritance pattern, who may benefit from early diagnosis and treatment.


Assuntos
Predisposição Genética para Doença/genética , Doença de Parkinson/genética , Adulto , Idade de Início , Povo Asiático/genética , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(9): 905-909, 2019 Sep 10.
Artigo em Zh | MEDLINE | ID: mdl-31515787

RESUMO

OBJECTIVE: To detect mutation of LBR gene in a pedigree affected with Pelger-Huёt anomaly (PHA) and to explore its clinical characteristics. METHODS: Genomic DNA was extracted from the pedigree and healthy controls. The 14 exons of the LBR gene were subjected to PCR amplification and Sanger sequencing. Suspected mutations were verified in other family members and 100 healthy controls. Polyphen-2 and SIFT software were used to predict the effect of the mutation, and Swiss-model software was used to simulate the protein structure. RESULTS: Three patients were found to carry a c.893G>A mutation in exon 8 of the LBR gene, which resulted in substitution of the 298th amino acid residue glycine by glutamic acid (p.Gly298Glu). The same mutation was not found in healthy family members and 100 healthy controls. The mutation was predicted to be damaging. Bioinformatic simulation showed the mutation has altered the 3D structure of the LBR protein. CONCLUSION: The c.893G>A (p.Gly298Glu) mutation in the LBR gene probably underlies the PHA in this pedigree and has enriched the spectrum of LBR gene mutations.


Assuntos
Anomalia de Pelger-Huët/genética , Receptores Citoplasmáticos e Nucleares/genética , Estudos de Casos e Controles , Análise Mutacional de DNA , Éxons , Humanos , Mutação , Linhagem , Reação em Cadeia da Polimerase , Receptor de Lamina B
13.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(4): 352-356, 2019 Apr 10.
Artigo em Zh | MEDLINE | ID: mdl-30950024

RESUMO

OBJECTIVE: To identify the mutation type of non-muscle myosin heavy chain 9 (MYH9) gene and investigate the clinical features of a pedigree affected with MYH9 gene-related disease. METHODS: Peripheral blood samples of the proband and his family members were collected. Routine blood tests were performed, which included platelet counting and Wright's staining to observe the granulocyte inclusions and giant platelets. PCR was used to amplify exons 2, 17, 27, 31, 39 and 41 of the MYH9 gene, and the mutation site was determined by Sanger sequencing. RESULTS: All patients from the pedigree presented a typical triad of thrombocytopenia, giant platelets, and inclusion bodies in leukocytes. In addition, two patients had nephritis and cataract. All affected members carried a heterozygous missense mutation of c.5521G>A (p.glu1841Lys) in exon 39 of the MYH9 gene. The same mutation was not found among healthy members of the pedigree and the controls. CONCLUSION: The c.5521G>A (p.Glu1841Lys) mutation in the MYH9 gene probably underlies the MYH9-related disease in this pedigree.


Assuntos
Proteínas Motores Moleculares/genética , Cadeias Pesadas de Miosina/genética , Trombocitopenia , Feminino , Testes Genéticos , Humanos , Masculino , Mutação , Linhagem
14.
BMC Plant Biol ; 18(1): 135, 2018 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-29940859

RESUMO

BACKGROUND: The relatively low efficiency of biolistic transformation and subsequent integration of multiple copies of the introduced gene/s significantly complicate the genetic modification of wheat (Triticum aestivum) and other plant species. One of the key factors contributing to the reproducibility of this method is the uniformity of the DNA/gold suspension, which is dependent on the coating procedure employed. It was also shown recently that the relative frequency of single copy transgene inserts could be increased through the use of nanogram quantities of the DNA during coating. RESULTS: A simplified DNA/gold coating method was developed to produce fertile transgenic plants, via microprojectile bombardment of callus cultures induced from immature embryos. In this method, polyethyleneglycol (PEG) and magnesium salt solutions were utilized in place of the spermidine and calcium chloride of the standard coating method, to precipitate the DNA onto gold microparticles. The prepared microparticles were used to generate transgenics from callus cultures of commercial bread wheat cv. Gladius resulting in an average transformation frequency of 9.9%. To increase the occurrence of low transgene copy number events, nanogram amounts of the minimal expression cassettes containing the gene of interest and the hpt gene were used for co-transformation. A total of 1538 transgenic wheat events were generated from 15,496 embryos across 19 independent experiments. The variation of single copy insert frequencies ranged from 16.1 to 73.5% in the transgenic wheat plants, which compares favourably to published results. CONCLUSIONS: The DNA/gold coating procedure presented here allows efficient, large scale transformation of wheat. The use of nanogram amounts of vector DNA improves the frequency of single copy transgene inserts in transgenic wheat plants.


Assuntos
Biolística/métodos , Mutagênese Insercional/métodos , Plantas Geneticamente Modificadas/genética , Triticum/genética , DNA de Plantas/genética , Ouro , Nanopartículas Metálicas , Triticum/crescimento & desenvolvimento
15.
Theor Appl Genet ; 131(12): 2765-2773, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30238255

RESUMO

KEY MESSAGE: A new and dominant R gene Stb19 is identified from a soft wheat cultivar 'Lorikeet' and was mapped on the distal region of chromosome 1DS. Two tightly linked KASP markers were also discovered and validated for molecular-assisted breeding programs. A new R gene, designated as Stb19, provides resistance to Zymoseptoria tritici in wheat. This new dominant gene resides on the short arm of chromosome 1D, exhibiting complete resistance to three Z. tritici isolates, WAI332, WAI251, and WAI161, at the seedling stage. A genetic linkage map, based on an F2:3 population of 'Lorikeet' and 'Summit,' found the Stb19 gene at a 9.3 cM region on 1DS, closely linked with two Kompetitive Allele-Specific PCR markers, snp_4909967 and snp_1218021. Further, the two markers were tested and validated in another F2:3 population and 266 different wheat accessions, which gave over 95% accuracy of resistance/susceptibility prediction. Combined with the physical location of the identified SNPs and the previous evidence of gene order on chromosome 1DS (centromere-Sr45-Sr33-Lr21-telomere), Stb19 is proposed to be located between Sr33 and Lr21. Thus, the newly discovered Stb19 along with the KASP markers represents an increase in genetic resources available for wheat breeding resistance to Z. tritici.


Assuntos
Resistência à Doença/genética , Genes Dominantes , Genes de Plantas , Doenças das Plantas/genética , Triticum/genética , Alelos , Ascomicetos/patogenicidade , Mapeamento Cromossômico , Marcadores Genéticos , Doenças das Plantas/microbiologia , Triticum/microbiologia
16.
BMC Oral Health ; 18(1): 213, 2018 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-30545332

RESUMO

BACKGROUND: The aim of the study was to assess bacterial sealability and bonding ability of methacrylate-based Resilon (RS, SybronEndo), Endo Rez (ER, Ultradent Products Inc), and epoxy-based AH Plus (AH, Dentsply/DeTrey), MTA Fill Apex (MTAF, Angelus Soluções Odontológicas) root canal sealers, and the effect of the smear layer removal on the sealability. METHODS: One hundred thirty root segments were instrumented up to apical size #60 and rinsed with 2.5% NaOCl. Half of the roots were rinsed with 5ml 17% EDTA to remove the smear layer. All the roots were filled with AH, ER, MTAF sealers and gutta-percha, or RS with Resilon cones. After storage at 37°C for 7 days the samples were mounted into bacterial leakage assay for 50 days. Another 100 roots were instrumented and rinsed as described above, split longitudinally, cut into the cervical, middle and apical parts. The sealers were injected through the plastic mould on the dentin surface. After 7 days of incubation at 37°C, bond strength was tested using a notched-edge test fixture (Crosshead, Ultradent Products Inc.) and a universal testing machine (Lloyd Instruments). RESULTS: AH revealed the longest mean time for bacterial resistance by 29.4 and 36.8 days (with and without smear layer, respectively) followed by RS (15.1 and 24.7 days, respectively). The difference between materials was significant (p<0.001). Bond strength values ranged from 0.2± 0.1 to 3.5± 0.7 MPa and increased from the apical to the cervical third. In the apical third, AH showed the highest mean (SD) bond values 1.4 (0.4) MPa and 1.7 (0.6) MPa (with and without smear, respectively, followed by RS, 0.5 (0.1) MPa and 0.8 (0.1) MPa, respectively. The difference between materials was significant (p=0.001). CONCLUSION: The effect of the smear layer removal on the sealability was material-dependent.


Assuntos
Colagem Dentária/métodos , Enterococcus faecalis , Resinas Sintéticas/uso terapêutico , Materiais Restauradores do Canal Radicular/uso terapêutico , Infiltração Dentária/epidemiologia , Infiltração Dentária/microbiologia , Infiltração Dentária/prevenção & controle , Análise do Estresse Dentário , Humanos , Resultado do Tratamento
17.
Macromol Rapid Commun ; 38(17)2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28691355

RESUMO

Strong and tough synthetic hydrogels have received ever-increasing interests due to their potential applications as load-bearing structural materials. However, strong, tough, and recyclable hydrogels in different forms that can be generated by different methods according to various practical applications still remain an intrinsic bottleneck. A simple one-pot synthesis of multiurea linkage segmented linear copolymers with easy recyclability, hybridization, and processability, including compression molding, solution casting, and spinning methods, to yield ultrastrong and tough hydrogel films or stretchable hydrogel fibers with diameters ranged from macro-, micro-, to nanoscale, is reported here.


Assuntos
Técnicas de Química Analítica/métodos , Hidrogéis/síntese química , Polímeros/química , Ureia/química , Hidrogéis/química
18.
Clin Nephrol ; 87 (2017)(4): 188-195, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28157068

RESUMO

AIMS: To improve diagnosis and treatment, we characterized Fabry disease combined with IgA nephropathy and its response to treatment clinically and pathologically in Chinese patients. MATERIALS AND METHODS: Clinical and pathological characteristics of 6 Chinese patients with renal biopsy-proven Fabry disease combined with IgA nephropathy were retrospectively analyzed. RESULTS: There were 4 males and 2 females in this study. All of the 6 patients presented with proteinuria. Microscopic hematuria was observed in case 4. Extrarenal symptoms included: acroparesthesia in case 1, 2, and 6, hypohidrosis in case 6 and angiokeratomas with hearing loss in case 3. By light microscopy, podocyte distension, with vacuolization, mesangial expansion, and interstitial lesions were found in all 6 cases; and focal segmental glomerulosclerosis was observed in 3 cases. Immunofluorescence microscopy showed deposition of IgA or predominant IgA with C3 in the mesangium. By electron microscopy, myelin figures and/or zebra bodies as well as electron-dense materials, were observed in the mesangium in the 6 cases. After admission and treatment with angiotensin converting enzyme inhibitors (ACEI) or angiotensin receptor blocker (ARB) together with immunosuppressant, glomerular filtration rate (GFR) decreased in 3 cases while it increased in the other 3 without statistical differences. CONCLUSIONS: The clinical and pathological features of Fabry disease combined with IgA nephropathy are diverse. Therefore, it is important to combine family history, clinical manifestations, α-galactosidase A activity and pathological features, especially ultrastructural changes, to improve the diagnosis and treatment of the disease.
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Assuntos
Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Doença de Fabry/metabolismo , Glomerulonefrite por IGA/tratamento farmacológico , Imunossupressores/uso terapêutico , alfa-Galactosidase/metabolismo , Adulto , Povo Asiático , Doença de Fabry/complicações , Feminino , Taxa de Filtração Glomerular , Mesângio Glomerular/patologia , Mesângio Glomerular/ultraestrutura , Glomerulonefrite por IGA/complicações , Glomerulosclerose Segmentar e Focal/tratamento farmacológico , Hematúria/etiologia , Humanos , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Podócitos/patologia , Podócitos/ultraestrutura , Proteinúria/etiologia , Estudos Retrospectivos , Adulto Jovem
19.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 34(4): 588-591, 2017 Aug 10.
Artigo em Zh | MEDLINE | ID: mdl-28777865

RESUMO

OBJECTIVE: To report on the result of thalassemia screening and genetic diagnosis for pregnant women from Guiyang region. METHODS: Prenatal screening for thalassemia was carried out based on erythrocyte parameters and hemoglobin electrophoresis. Single-tube multiplex GAP-PCR and PCR-reverse dot blot hybridization were performed on suspected cases to identify common alpha- and beta- thalassemia mutations, and direct sequencing was used for identifying rare mutations. RESULTS: Among 13 738 pregnant women, 1745 (12.70%) were suspected as thalassemia. In terms of native place, the provinces with highest screening-positive rates were Guangxi, Guangdong, Jiangxi and Guizhou. And the ethnic groups with highest screening-positive rates were Zhuang, Li, and Buyi. Among 801 women subjected to genetic testing, 457 (57.05%) were diagnosed with thalassemia. In total 9 genotypes of alpha- thalassemia were detected, with the most common genotypes being --SEA/alpha alpha (63.35%), - alpha3.7/alpha alpha (19.37%) and - alpha4.2/alpha alpha (8.90%). Eleven genotypes of beta- thalassemia were detected, with the most common genotypes being CD17/N (42.91%), CD41-42/N (32.46%) and IVS-II-654/N (11.94%). Two cases were detected with rare beta-thalassemia mutations (CD54-58/N and IVS-I-130/N). CONCLUSION: The screening-positive rate of thalassemia among pregnant women in Guiyang region is relatively high. The rates have shown substantial difference in terms of native place and ethnic group. Thalassemia-related mutations in Guizhou region have a diverse spectrum, which showed certain difference from those of other regions.


Assuntos
Talassemia/genética , Adolescente , Adulto , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Gravidez , Diagnóstico Pré-Natal/métodos , Adulto Jovem
20.
Plant Biotechnol J ; 14(2): 820-32, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26150199

RESUMO

Plants respond to abiotic stresses by changes in gene regulation, including stress-inducible expression of transcriptional activators and repressors. One of the best characterized families of drought-related transcription factors are dehydration-responsive element binding (DREB) proteins, known as C-repeat binding factors (CBF). The wheat DREB/CBF gene TaRAP2.1L was isolated from drought-affected tissues using a dehydration-responsive element (DRE) as bait in a yeast one-hybrid screen. TaRAP2.1L is induced by elevated abscisic acid, drought and cold. A C-terminal ethylene responsive factor-associated amphiphilic repression (EAR) motif, known to be responsible for active repression of target genes, was identified in the TaRAP2.1L protein. It was found that TaRAP2.1L has a unique selectivity of DNA-binding, which differs from that of DREB activators. This binding selectivity remains unchanged in a TaRAP2.1L variant with an inactivated EAR motif (TaRAP2.1Lmut). To study the role of the TaRAP2.1L repressor activity associated with the EAR motif in planta, transgenic wheat overexpressing native or mutated TaRAP2.1L was generated. Overexpression of TaRAP2.1L under constitutive and stress-inducible promoters in transgenic wheat and barley led to dwarfism and decreased frost tolerance. By contrast, constitutive overexpression of the TaRAP2.1Lmut gene had little or no negative influence on wheat development or grain yield. Transgenic lines with the TaRAP2.1Lmut transgene had an enhanced ability to survive frost and drought. The improved stress tolerance is attributed to up-regulation of several stress-related genes known to be downstream genes of DREB/CBF activators.


Assuntos
Proteínas de Plantas/metabolismo , Proteínas Repressoras/metabolismo , Estresse Fisiológico/genética , Transcrição Gênica , Triticum/fisiologia , Ácido Abscísico/farmacologia , Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/genética , Sequência de Aminoácidos , Proteínas de Ligação a DNA/metabolismo , Congelamento , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Hordeum/genética , Modelos Moleculares , Proteínas Mutantes/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Proteínas de Plantas/química , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Domínios Proteicos , Alinhamento de Sequência , Estresse Fisiológico/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos , Triticum/efeitos dos fármacos , Triticum/genética , Triticum/crescimento & desenvolvimento , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
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