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1.
J Xray Sci Technol ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38607727

RESUMO

BACKGROUND: Accurate diagnosis and subsequent delineated treatment planning require the experience of clinicians in the handling of their case numbers. However, applying deep learning in image processing is useful in creating tools that promise faster high-quality diagnoses, but the accuracy and precision of 3-D image processing from 2-D data may be limited by factors such as superposition of organs, distortion and magnification, and detection of new pathologies. The purpose of this research is to use radiomics and deep learning to develop a tool for lung cancer diagnosis. METHODS: This study applies radiomics and deep learning in the diagnosis of lung cancer to help clinicians accurately analyze the images and thereby provide the appropriate treatment planning. 86 patients were recruited from Bach Mai Hospital, and 1012 patients were collected from an open-source database. First, deep learning has been applied in the process of segmentation by U-NET and cancer classification via the use of the DenseNet model. Second, the radiomics were applied for measuring and calculating diameter, surface area, and volume. Finally, the hardware also was designed by connecting between Arduino Nano and MFRC522 module for reading data from the tag. In addition, the displayed interface was created on a web platform using Python through Streamlit. RESULTS: The applied segmentation model yielded a validation loss of 0.498, a train loss of 0.27, a cancer classification validation loss of 0.78, and a training accuracy of 0.98. The outcomes of the diagnostic capabilities of lung cancer (recognition and classification of lung cancer from chest CT scans) were quite successful. CONCLUSIONS: The model provided means for storing and updating patients' data directly on the interface which allowed the results to be readily available for the health care providers. The developed system will improve clinical communication and information exchange. Moreover, it can manage efforts by generating correlated and coherent summaries of cancer diagnoses.

2.
Front Plant Sci ; 14: 1242913, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37780505

RESUMO

Plant hormones play important roles in seed development; however, transcriptional regulation of their metabolism and levels of the respective bioactive forms during barley seed development is poorly understood. To this end, this study performed a comprehensive analysis of changes in the expression patterns phytohormone metabolism genes and levels of the respective bioactive forms in the embryo and endosperm tissues. Our study showed the presence of elevated levels of abscisic acid (ABA), bioactive forms of gibberellins (GAs), jasmonate (JA) and cytokinins (CKs), auxin and salicylic acid (SA) in the endosperm and embryo tissues at early stage of seed filling (SF). The levels of all hormones in both tissues, except that of ABA, decreased to low levels during SF. In contrast, embryonic ABA level increased during SF and peaked at physiological maturity (PM) while the endospermic ABA was maintained at a similar level observed during SF. Although its level decreased high amount of ABA was still present in the embryo during post-PM. We detected low levels of ABA in the endosperm and all the other hormones in both tissues during post-PM phase except the relatively higher levels of jasmonoyl-isoleucine and SA detected at late stage of post-PM. Our data also showed that spatiotemporal changes in the levels of plant hormones during barley seed development are mediated by the expression of specific genes involved in their respective metabolic pathways. These results indicate that seed development in barley is mediated by spatiotemporal modulation in the metabolism and levels of plant hormones.

3.
Data Brief ; 50: 109541, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37732293

RESUMO

The present data profile a large scale transcriptome changes associated with variations in seed dormancy level induced by seed development temperature in hexaploid wheat. Seed dormancy is an important trait that inhibits seed germination under optimal conditions and therefore has important implication in preventing the incidence of preharvest sprouting, which refers to the germination of seeds on the mother plant prior to harvest, in wheat. Since preharvest sprouting, which causes a significant reduction in seed yield and quality in wheat, is closely associated with low level of seed dormancy manifested in modern wheat cultivars, it is important to develop wheat cultivars with optimal level of dormancy to enhance wheat yield and quality. Thus, elucidation of the molecular mechanisms that regulate seed dormancy is critical for the development of preharvest sprouting resistant wheat cultivars. The data we are presenting here were generated from total RNA samples extracted from imbibed seeds of a dormant wheat (Triticum aestivum L.) genotype that were developed at different temperatures using the Affymetrix GeneChip Wheat Genome Array. The raw and normalized formats of these data are deposited in the NCBI's gene expression data repository, Gene Expression Ominbus (GEO) with accession number GSE153527.

4.
Theor Appl Genet ; 136(9): 202, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37642745

RESUMO

KEY MESSAGE: Genome-wide association study of diverse barley genotypes identified loci, single nucleotide polymorphisms and candidate genes that control seed dormancy and therefore enhance resistance to preharvest sprouting. Preharvest sprouting (PHS) causes significant yield and quality loss in barley and it is strongly associated with the level of seed dormancy. This study performed genome-wide association study using a collection of 255 diverse barley genotypes grown over four environments to identify loci controlling dormancy/PHS. Our phenotypic analysis revealed substantial variation in germination index/dormancy levels among the barley genotypes. Marker-trait association and linkage disequilibrium (LD) decay analyses identified 16 single nucleotide polymorphisms (SNPs) and two QTLs associated with dormancy/PHS, respectively, on chromosome 3H and 5H explaining 6.9% to 11.1% of the phenotypic variation. QTL.5H consist of 14 SNPs of which 12 SNPs satisfy the FDR threshold of α = 0.05, and it may represent the SD2 locus. The QTL on 3H consists of one SNP that doesn't satisfy FDR (α = 0.05). Genes harbouring the significant SNPs were analyzed for their expression pattern in the seeds of selected dormant and non-dormant genotypes. Of these genes, HvRCD1, HvPSRP1 and HvF3H exhibited differential expression between the dormant and non-dormant seed samples, suggesting their role in controlling seed dormancy/PHS. Three SNPs located within the differentially expressed genes residing in QTL.5H explained considerable phenotypic variation (≥ 8.6%), suggesting their importance in regulating PHS resistance. Analysis of the SNP marker data in QTL.5H identified a haplotype for PHS resistance. Overall, the study identified loci, SNPs and candidate genes that control dormancy and therefore play important roles in enhancing PHS resistance in barley through marker-assisted breeding.


Assuntos
Hordeum , Hordeum/genética , Estudo de Associação Genômica Ampla , Transcriptoma , Melhoramento Vegetal , Genótipo
5.
Radiol Case Rep ; 18(4): 1544-1548, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36815147

RESUMO

Oligodendroglioma, the third most common glioma, accounts for 5% of primary brain tumors and around 20% of all glial neoplasms. They are quite uncommon in children. Here, we aimed to show an unusual case of a 9-year-old boy developing a huge anaplastic oligodendroglioma. A high-grade astrocytoma-like supratentorial tumor was discovered by a sophisticated brain scan employing magnetic resonance imaging. The tumor was identified by histopathology as an anaplastic oligodendroglioma. Anaplastic oligodendroglioma should be considered while making the differential diagnosis of high-grade astrocytoma notwithstanding its rarity.

6.
Childs Nerv Syst ; 39(2): 471-479, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35804268

RESUMO

PURPOSE: Head circumference (HC) is an important clinical tool for following head growth in children with craniosynostosis (CS). The purpose of this study is to quantify the usefulness of HC along continuum of CS care, from diagnosis to pre- and post-operative (pre-op, post-op) follow-up in Vietnamese children. METHODS: A prospective cohort of 54 nonsyndromic single-suture CS patients undergoing open surgery from January 2015 to January 2020 was collected at Children's Hospital 2, Vietnam. HC z-score on admission was compared with World Health Organization (WHO) standards to evaluate for utility in initial diagnosis. Pre-op and post-op HC were compared to demonstrate the evolution of head growth following reconstruction. RESULTS: Nonsyndromic single-suture CS was more predominant in males (79.6%) than in females (20.4%). The mean HC z-score was - 0.38 [Formula: see text] 1.29 similar to normal WHO standards regardless of which sutural involvement. The HC z-score increased above + 1 standard deviation (SD) significantly at 3 months of follow-up (p < 0.001); however, the trajectory gradually decreased after the first year of surgery. One patient (1.8%, 1/54) demonstrated restenosis and delayed intracranial hypertension (DIH) 4 years after reconstruction. CONCLUSIONS: The HC in nonsyndromic single-suture CS children presents similarly to the values of healthy children. Additionally, HC reliably increased after reconstruction and gradually normalized over subsequent years. This indicator is consistent in Southeast Asian populations and should be used to follow all patients to assess the normal progression of post-op head growth and as a useful indicator of suspected recurrent synostosis.


Assuntos
Craniossinostoses , População do Sudeste Asiático , Masculino , Feminino , Humanos , Criança , Lactente , Estudos Prospectivos , Vietnã , Craniossinostoses/cirurgia , Suturas
7.
RSC Adv ; 12(43): 27855-27867, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36320272

RESUMO

Using electrochemically exfoliated graphene oxide (GO)-modified screen-printed carbon electrodes for the detection of furazolidone (FZD), a nitrofuran antibiotic, was explored. In this study, we designed some GO samples possessing different oxygen functional group content/defect density by using ultrasonic irradiation or microwave techniques as supporting tools. The difference in physical characteristics of GO led to the remarkable change in kinetic parameters (electron transfer rate constant (k s) and transfer coefficient (α)) of electron transfer reactions at K 3/K 4 probes as well as the FZD analyte. Obtained results reveal that the GO-ultrasonic sample showed the highest electrochemical response toward FZD detection owing to the increase in defect density and number of edges in the GO nanosheets under ultrasonic irradiation. The proposed electrochemical nanosensor enabled the monitoring of FZD in the linear range from 1 µM to 100 µM with an electrochemical sensitivity of 1.03 µA µM-1 cm-2. Tuning suitable electronic structures of GO suggests the potentiality of advanced GO-based electrochemical nanosensor development in food-producing animal safety monitoring applications.

8.
Plant Sci ; 324: 111432, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36029895

RESUMO

Abscisic acid (ABA) regulates seed dormancy and therefore preharvest sprouting (PHS) in wheat. This study investigated the contribution of transcriptional regulation of ABA metabolism and signaling genes to genetic variation in dormancy of wheat seeds. Our results showed that genetic variation in seed dormancy is highly correlated with ABA content (r > 0.86), which, in turn, was closely associated with the expression levels of ABA biosynthesis genes, TaNCED1 (r = 0.78) and TaNCED2 (r = 0.67). A relatively lower correlation was observed between ABA content and the expression levels of ABA catabolism genes, TaCYP707A1 (r = 0.51) and TaCYP707A2 (r = 0.57). The expression level of TaABI5 exhibited strong associations with the levels of ABA (r = 0.8) and seed dormancy (r > 0.9), indicating the importance of seed ABA sensitivity in mediating genetic variation in dormancy. Furthermore, high positive correlations were prevalent between the expression patterns of TaABI5 and TaNCED1 (r = 0.91) or TaNCED2 (r = 0.82). Overall, our results implicated the significance of TaNCEDs and TaABI5 in regulating genetic variation in ABA level and sensitivity and thereby seed dormancy, highlighting the potential use of these genes to develop molecular markers for incorporating PHS resistance in wheat.


Assuntos
Dormência de Plantas , Triticum , Ácido Abscísico/metabolismo , Regulação da Expressão Gênica de Plantas , Variação Genética , Germinação/genética , Dormência de Plantas/genética , Sementes/metabolismo , Triticum/metabolismo
9.
Int J Mol Sci ; 23(3)2022 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-35163167

RESUMO

The present study investigated the role of salicylic acid (SA) in regulating morpho-anatomical adaptive responses of a wheat plant to waterlogging. Our pharmacological study showed that treatment of waterlogged wheat plants with exogenous SA promotes the formation axile roots and surface adventitious roots that originate from basal stem nodes, but inhibits their elongation, leading to the formation of a shallow root system. The treatment also enhanced axile root formation in non-waterlogged plants but with only slight reductions in their length and branch root formation. Exogenous SA enhanced the formation of root aerenchyma, a key anatomical adaptive response of plants to waterlogging. Consistent with these results, waterlogging enhanced SA content in the root via expression of specific isochorismate synthase (ICS; ICS1 and ICS2) and phenylalanine ammonia lyase (PAL; PAL4, PAL5 and PAL6) genes and in the stem nodes via expression of specific PAL (PAL5 and PAL6) genes. Although not to the same level observed in waterlogged plants, exogenous SA also induced aerenchyma formation in non-waterlogged plants. The findings of this study furthermore indicated that inhibition of ethylene synthesis in SA treated non-waterlogged and waterlogged plants does not have any effect on SA-induced emergence of axile and/or surface adventitious roots but represses SA-mediated induction of aerenchyma formation. These results highlight that the role of SA in promoting the development of axile and surface adventitious roots in waterlogged wheat plants is ethylene independent while the induction of aerenchyma formation by SA requires the presence of ethylene.


Assuntos
Raízes de Plantas/efeitos dos fármacos , Ácido Salicílico/farmacologia , Triticum/crescimento & desenvolvimento , Adaptação Biológica/efeitos dos fármacos , Inundações , Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/genética , Transferases Intramoleculares/genética , Fenilalanina Amônia-Liase/genética , Raízes de Plantas/metabolismo , Ácido Salicílico/metabolismo , Plântula/metabolismo , Triticum/efeitos dos fármacos , Água
10.
J Exp Bot ; 73(8): 2434-2453, 2022 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-35104307

RESUMO

Jasmonate (JA) regulates seed dormancy and germination; however, the underlying mechanisms remain poorly understood. Furthermore, it is unclear if JA is an essential regulator of dormancy and germination. We investigated whether the role of JA in regulating seed dormancy in wheat (Triticum aestivum L.) is mediated by modulation of gibberellin (GA)/abscisic acid (ABA) balance and if the reciprocal modulation of JA level and sensitivity is required for GA-mediated dormancy loss using physiological, pharmacological, and targeted transcriptomic and metabolomic approaches. JA-induced dormancy release in wheat seeds was associated with no change in GA level but up-regulation of GA signaling and ABA catabolism genes, and reduction of the ABA level. Although JA did not affect the expression levels of ABA signaling genes, up-regulation of germination-associated genes indicates a contribution of reduced ABA sensitivity to dormancy release. After-ripening-mediated dormancy loss was also associated with JA-GA synergistic and JA-ABA antagonistic interplays. The prevalence of no effect of GA, which effectively broke dormancy, on the JA-Ile level and expression patterns of JA biosynthesis/signaling and responsive genes reflects that GA-mediated dormancy release occurs independently of JA. Our study concludes that JA induces seed dormancy release in wheat via modulating ABA/GA balance; however, JA is not an essential regulator of dormancy and germination.


Assuntos
Ácido Abscísico , Dormência de Plantas , Ácido Abscísico/metabolismo , Ciclopentanos , Regulação da Expressão Gênica de Plantas , Germinação/genética , Giberelinas/metabolismo , Oxilipinas , Dormência de Plantas/fisiologia , Sementes/metabolismo , Triticum/fisiologia
11.
J Plant Physiol ; 270: 153637, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35144140

RESUMO

Jasmonates play important roles in several plant developmental processes and responses to biotic and abiotic stresses. This study identified a gene encoding jasmonate resistant 1 (JAR1) protein that catalyzes the production of bioactive jasmonoyl-isoleucine (JA-Ile) from hexaploid wheat (Triticum aestivum L), designated as TaJAR1B. The nucleotide sequence of TaJAR1B and amino acid sequence of the corresponding protein exhibited high identity and similarity with other plant JAR1s. Feeding the culture of E. coli cells heterologously expressing TaJAR1B with jasmonic acid (JA) resulted in the production of JA-Ile, indicating the functionality of TaJAR1B in converting JA to JA-Ile. TaJAR1B was highly expressed in the internodes of adult plants and maturing seeds. Salt treatment induced the expression level of TaJAR1B in seedling tissues. Our results indicate that TaJAR1B encodes a functional JAR and is involved in the regulation of plant growth and developmental processes and response to salinity in wheat.

12.
J Neurosurg Pediatr ; 28(5): 508-515, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34450594

RESUMO

OBJECTIVE: There is a global deficit of pediatric neurosurgical care, and the epidemiology and overall surgical care for craniosynostosis is not well characterized at the global level. This study serves to highlight the details and early surgical results of a neurosurgical educational partnership and subsequent local scale-up in craniosynostosis correction. METHODS: A prospective case series was performed with inclusion of all patients undergoing correction of craniosynostosis by extensive cranial vault remodeling at Children's Hospital 2, Ho Chi Minh City, Vietnam, between January 1, 2015, and December 31, 2019. RESULTS: A total of 76 patients were included in the study. The group was predominantly male, with a male-to-female ratio of 3.3:1. Sagittal synostosis was the most common diagnosis (50%, 38/76), followed by unilateral coronal (11.8%, 9/76), bicoronal (11.8%, 9/76), and metopic (7.9%, 6/76). The most common corrective technique was anterior cranial vault remodeling (30/76, 39.4%) followed by frontoorbital advancement (34.2%, 26/76). The overall mean operative time was 205.8 ± 38.6 minutes, and the estimated blood loss was 176 ± 89.4 mL. Eleven procedures were complicated by intraoperative durotomy (14.5%, 11/76) without any damage of dural venous sinuses or brain tissue. Postoperatively, 4 procedures were complicated by wound infection (5.3%, 4/76), all of which required operative wound debridement. There were no neurological complications or postoperative deaths. One patient required repeat reconstruction due to delayed intracranial hypertension. There was no loss to follow-up. All patients were followed at outpatient clinic, and the mean follow-up period was 32.3 ± 18.8 months postoperatively. CONCLUSIONS: Surgical care for pediatric craniosynostosis can be taught and sustained in the setting of collegial educational partnerships with early capability for high surgical volume and safe outcomes. In the setting of the significant deficit in worldwide pediatric neurosurgical care, this study provides an example of the feasibility of such relationships in addressing this unmet need.


Assuntos
Craniossinostoses/cirurgia , Procedimentos Neurocirúrgicos , Craniossinostoses/epidemiologia , Feminino , Humanos , Lactente , Masculino , Procedimentos Neurocirúrgicos/educação , Pediatria , Estudos Prospectivos , Procedimentos de Cirurgia Plástica/métodos , Resultado do Tratamento , Vietnã
13.
J Parasitol ; 107(2): 172-178, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33662117

RESUMO

Skrjabinoptera vietnamensis n. sp. is described from specimens recovered from the stomach of Eutropis macularia in north-central Vietnam. The new species is characterized by the medium-sized male worms (6.7-8.7 mm in length and 154-182 µm in width) relative to known members of the genus, 2 pointed spicules of unequal length (87-112 µm and 56-72 µm in length), and 10 pairs of caudal papillae. Female worms are larger than male worms (10.7-18.4 mm in length and 264-411 µm in width), with the vulva situated in the anterior part, and embryonated, elliptical eggs, 35-46 µm long by 20-24 µm wide. Skrjabinoptera vietnamensis n. sp. represents the ninth species assigned to the genus and the first species recorded from the Oriental region. Partial sequences of the 18S ribosomal RNA gene (rDNA), and cytochrome c oxidase subunit 1 (COI) are provided for the new species. The molecular phylogenetic position of the genus Skrjabinoptera is briefly discussed.


Assuntos
Lagartos/parasitologia , Infecções por Spirurida/veterinária , Spirurina/classificação , Animais , Teorema de Bayes , DNA de Helmintos/química , DNA de Helmintos/genética , DNA de Helmintos/isolamento & purificação , DNA Ribossômico/química , Feminino , Masculino , Microscopia Eletrônica de Varredura/veterinária , Filogenia , RNA Ribossômico 18S/genética , Infecções por Spirurida/parasitologia , Spirurina/anatomia & histologia , Spirurina/genética , Spirurina/ultraestrutura , Estômago/parasitologia , Vietnã
14.
Tree Physiol ; 41(4): 529-543, 2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-31595966

RESUMO

To elucidate the role of phytohormones during bud dormancy progression in the Japanese pear (Pyrus pyrifolia Nakai), we investigated changes in phytohormone levels of indole acetic acid (IAA), gibberellic acid (GA), abscisic acid (ABA) and trans-zeatin (tZ). Using ultra-performance liquid chromatography/mass spectrometry/mass spectrometry, we monitored phytohormone levels in the buds of field-grown and potted trees that were artificially heated to modify the timing of dormancy and flowering (spring flush) progression. We also analyzed the expression of GA- and ABA-metabolic genes during dormancy. Indole acetic acid and tZ levels were low during dormancy and increased toward the flowering stage. Gibberellic acid levels were maintained at relatively high concentrations during the dormancy induction stage, then decreased before slightly increasing prior to flowering. The low GA concentration in potted trees compared with field-grown trees indicated that GA functions in regulating tree vigor. Abscisic acid levels increased from the dormancy induction stage, peaked near endodormancy release and steadily decreased before increasing again before the flowering stage. The ABA peak levels did not always coincide with endodormancy release, but peak height correlated with flowering uniformity, suggesting that a decline in ABA concentration was not necessary for resumption of growth but the abundance of ABA might be associated with dormancy depth. From monitoring the expression of genes related to GA and ABA metabolism, we inferred that phytohormone metabolism changed significantly during dormancy, even though the levels of bioactive molecules were consistently low. Phytohormones regulate dormancy progression not only upon the reception of internal signals but also upon sensing ambient conditions.


Assuntos
Pyrus , Ácido Abscísico , Flores/genética , Flores/metabolismo , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Dormência de Plantas/genética , Reguladores de Crescimento de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pyrus/genética
15.
Biology (Basel) ; 9(8)2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32708038

RESUMO

This study examined the expression patterns of antioxidative genes and the activity of the corresponding enzymes in the excess moisture-stressed seedlings of soybean in response to seed treatment with polyamines, spermine (Spm) and spermidine (Spd). At the 4 day after planting (DAP) stage, the excess moisture impaired the embryo axis growth, and this effect is associated with the downregulation of superoxide dismutase (GmSOD1) expression and SOD activity in the cotyledon. Seed treatment with Spm reversed the effects of excess moisture on embryo axis growth partly through enhancing glutathione reductase (GR) activity, in both the cotyledon and embryo axis, although no effect on the GmGR expression level was evident. Excess moisture inhibited the shoot and root growth in 7 DAP seedlings, and this is associated with decreased activities of GR in the shoot and SOD in the root. The effect of excess moisture on shoot and root growth was reversed by seed treatment with Spd, and this was mediated by the increased activities of ascorbate peroxidase (APX), catalase (CAT) and GR in the shoot, and APX in the root, however, only GR in the shoot appears to be regulated transcriptionally. Root growth was also reversed by seed treatment with Spm with no positive effect on gene expression and enzyme activity.

16.
Polymers (Basel) ; 13(1)2020 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-33396794

RESUMO

In this study, we present the fabrication of nitrile butadiene rubber/waste leather fiber (NBR/WLF) composites with different weight percentages of WLF and NBR (0/100, 20/80, 30/70, 40/60, 50/50, 60/40 wt/wt). WLF was prepared by cutting the scrap leathers from the waste product of the Vietnamese leather industry. Subsequently, in order to make the short fibers, it was mixed by a hammer mill. The characteristics of WLF/NBR composites such as mechanical properties (tensile strength, tear strength, hardness), dynamic mechanical properties, toluene absorption, and morphology were carefully evaluated. As a result, the tensile strength and tear strength become larger with increasing WLF content from 0 to 50 wt% and they decrease when further increasing WLF content. The highest tensile strength of 12.5 MPa and tear strength of 72.47 N/mm were achieved with the WLF/NBR ratio of 50/50 wt%. Both hardness and resistance of the developed materials with toluene increased with increasing WLF content. The SEM results showed a good adhesion of NBR matrix and the WLF. The increasing of storage modulus (E') in comparison with raw NBR showed good compatibility between WLF and NBR matrix. This research showed that the recycled material from waste leather and NBR was successfully prepared and has great potential for manufacturing products such as floor covering courts and playgrounds, etc.

17.
J Exp Bot ; 71(6): 1985-2004, 2020 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-31872216

RESUMO

This study aimed to gain insights into the molecular mechanisms underlying the role of ethylene in regulating germination and seedling growth in wheat by combining pharmacological, molecular, and metabolomics approaches. Our study showed that ethylene does not affect radicle protrusion but controls post-germination endospermic starch degradation through transcriptional regulation of specific α-amylase and α-glucosidase genes, and this effect is mediated by alteration of endospermic bioactive gibberellin (GA) levels, and GA sensitivity via expression of the GA signaling gene, TaGAMYB. Our data implicated ethylene as a positive regulator of embryo axis and coleoptile growth through transcriptional regulation of specific TaEXPA genes. These effects were associated with modulation of GA levels and sensitivity, through expression of GA metabolism (TaGA20ox1, TaGA3ox2, and TaGA2ox6) and signaling (TaGAMYB) genes, respectively, and/or the abscisic acid (ABA) level and sensitivity, via expression of specific ABA metabolism (TaNCED2 or TaCYP707A1) and signaling (TaABI3) genes, respectively. Ethylene appeared to regulate the expression of TaEXPA3 and thereby root growth through its control of coleoptile ABA metabolism, and root ABA signaling via expression of TaABI3 and TaABI5. These results show that spatiotemporal modulation of ABA/GA balance mediates the role of ethylene in regulating post-germination storage starch degradation and seedling growth in wheat.


Assuntos
Ácido Abscísico , Germinação , Etilenos , Regulação da Expressão Gênica de Plantas , Giberelinas , Reguladores de Crescimento de Plantas , Plântula/genética , Sementes , Triticum/genética
18.
Parasit Vectors ; 12(1): 585, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31842951

RESUMO

BACKGROUND: Triatoma rubrofasciata is the only kissing bug species distributed globally. In the Americas, this species transmits the parasite Trypanosoma cruzi, responsible for Chagas disease. The presence of T. rubrofasciata in several Asian countries has greatly increased recently. In Vietnam, it is found in large numbers, closely associated with human environments. Although T. rubrofasciata from Asia is not infected with Tryp. cruzi, it carries other parasites such as Trypanosoma lewisi and Trypanosoma conorhini. Reports of bites by T. rubrofasciata have increased significantly in several places of Vietnam, becoming a public health problem as it produces severe anaphylactic reactions. METHODS: Specimens of T. rubrofasciata were collected from seven provinces in central Vietnam. We analyzed different biological attributes (life-cycle, starvation resistance, feeding and reproductive capacities) and genetic characteristics (chromosomes and DNA sequences) of T. rubrofasciata from Vietnam and compared them with Brazilian specimens. Natural infection with Tryp. conorhini and Tryp. lewisi were analyzed in a sample of 100 collected insects. RESULTS: Species identification of T. rubrofasciata from central Vietnam was corroborated by genetic markers. Cytogenetic analyses showed that T. rubrofasciata from central Vietnam share the same chromosomal characteristics with individuals from Brazil and Hanoi. DNA sequence analyses of a mitochondrial cytochrome b gene fragment showed little variation between Old and New World specimens. Our study sample, compared with Brazilian individuals, showed a higher survival capacity revealed by a higher hatching rate (98% compared with 80.5%), a larger amount of blood taken in single meal and long-term starvation resistance. Furthermore, this species had a high natural rate of infection with Tryp. conorhini (46%) and Tryp. lewisi (27%). CONCLUSIONS: For T. rubrofasciata of Vietnam, a high rate of fecundity throughout the year, a high capacity for starvation, and its occurrence in synanthropic environments of urban areas with a high availability of food sources are risk factors to be taken into account by vector control campaigns. The several allergic reactions caused by their bites and their high infection with Tryp. lewisi highlight the need to implement specific control programmes for T. rubrofasciata in Vietnam.


Assuntos
Comportamento Alimentar , Insetos Vetores/fisiologia , Estágios do Ciclo de Vida , Reprodução , Triatoma/fisiologia , Animais , Brasil , Citocromos b/genética , Citogenética , Variação Genética , Genótipo , Insetos Vetores/classificação , Insetos Vetores/genética , Insetos Vetores/parasitologia , Cariótipo , Análise de Sequência de DNA , Triatoma/classificação , Triatoma/genética , Triatoma/parasitologia , Trypanosoma/isolamento & purificação , Vietnã
19.
Front Plant Sci ; 10: 823, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31333690

RESUMO

The phytopathogenic fungus Leptosphaeria maculans causes the blackleg disease on Brassica napus, resulting in severe loss of rapeseed production. Breeding of resistant cultivars containing race-specific resistance genes is provably effective to combat this disease. While two allelic resistance genes LepR3 and Rlm2 recognizing L. maculans avirulence genes AvrLm1 and AvrLm2 at plant apoplastic space have been cloned in B. napus, the downstream gene expression network underlying the resistance remains elusive. In this study, transgenic lines expressing LepR3 and Rlm2 were created in the susceptible "Westar" cultivar and inoculated with L. maculans isolates containing different sets of AvrLm1 and AvrLm2 for comparative transcriptomic analysis. Through grouping the RNA-seq data based on different levels of defense response, we find LepR3 and Rlm2 orchestrate a hierarchically regulated gene expression network, consisting of induced ABA acting independently of the disease reaction, activation of signal transduction pathways with gradually increasing intensity from compatible to incompatible interaction, and specifically induced enzymatic and chemical actions contributing to hypersensitive response with recognition of AvrLm1 and AvrLm2. This study provides an unconventional investigation into LepR3 and Rlm2-mediated plant defense machinery and adds novel insight into the interaction between surface-localized receptor-like proteins (RLPs) and apoplastic fungal pathogens.

20.
Sci Rep ; 9(1): 3983, 2019 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-30850728

RESUMO

To gain insights into the roles of cytokinin (CK) and auxin in regulating dormancy during seed maturation in wheat, we examined changes in the levels of CK and indole-3-acetic acid (IAA) and expression patterns of their metabolism and signaling genes in embryonic and endospermic tissues of dormant and non-dormant genotypes. Seed maturation was associated with a decrease in the levels of isopentenyladenine in both tissues mainly via repression of the CK biosynthetic TaLOG genes. Differential embryonic trans-zeatin content and expression patterns of the CK related genes including TacZOG, TaGLU and TaARR12 between maturing seeds of the two genotypes implicate CK in the control of seed dormancy induction and maintenance. Seed maturation induced a decrease of IAA level in both tissues irrespective of genotype, and this appeared to be mediated by repression of specific IAA biosynthesis, transport and IAA-conjugate hydrolysis genes. The differential embryonic IAA content and expression pattern of the IAA biosynthetic gene TaAO during the early stage of seed maturation between the two genotypes imply the role of IAA in dormancy induction. It appears from our data that the expression of specific auxin signaling genes including TaRUB, TaAXR and TaARF mediate the role of auxin signaling in dormancy induction and maintenance during seed maturation in wheat.


Assuntos
Citocininas/metabolismo , Ácidos Indolacéticos/metabolismo , Dormência de Plantas/genética , Sementes/genética , Transdução de Sinais/genética , Transcriptoma/genética , Triticum/genética , Endosperma/genética , Endosperma/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas/genética , Genótipo , Germinação/genética , Reguladores de Crescimento de Plantas/metabolismo , Transcrição Gênica/genética , Triticum/metabolismo
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