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1.
BMC Complement Med Ther ; 24(1): 242, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38907195

RESUMO

BACKGROUND: This study explores the medicinal plant knowledge of the Baiku Yao, a unique ethnic group in China. Despite existing research on their ethnobotanical practices, a comprehensive understanding of their medicinal flora remains lacking. This study aims to document and analyze the species distribution, utilization, and traditional knowledge of medicinal plants used by Baiku Yao. METHODS: Ethnobotanical surveys were conducted in various Baiku Yao villages across different seasons from 2019 to 2023. Informants were interviewed, and plant specimens were collected and identified. Statistical analyses, including the Relative Frequency of Citation (RFC), were employed to understand plant importance in Baiku Yao culture. RESULTS: In an ethnobotanical survey conducted in the Baiku Yao region, 434 medicinal plant species were documented, highlighting significant ethnobotanical diversity and a deep cultural integration of traditional medicinal practices. The study revealed pronounced geographical variations in plant knowledge among villages, with a notable reliance on wild plants, as 85.48% were sourced from the wild, reflecting unique local ethnobotanical knowledge. Predominantly herbs and shrubs were used due to their accessibility and abundance in the local environment. High Relative Frequency of Citation (RFC) values for certain species underscored their importance for local health needs and additional economic value. The utilization of various plant parts, particularly whole plants, roots, and leaves, indicates a holistic approach to medicinal applications, adapted to combat prevalent health issues such as skin and infectious diseases. The study also uncovered the Baiku Yao's cultural practices for countering "Gu" afflictions-a range of pathogenic conditions-with 18 diverse antidote plants used for skin, digestive, and musculoskeletal disorders. The study underscores the imperative of preserving this rich medicinal heritage through innovative models that engage youth and leverage new media, ensuring the inheritance and evolution of Baiku Yao's traditional knowledge. CONCLUSIONS: Baiku Yao's medicinal plant use reflects a deep, culturally ingrained knowledge, closely tied to local ecology. The study highlights the importance of preserving this unique ethnobotanical heritage and suggests interdisciplinary approaches for future research.


Assuntos
Etnobotânica , Plantas Medicinais , Humanos , China , Etnicidade , Conhecimentos, Atitudes e Prática em Saúde , Medicina Tradicional Chinesa , Inquéritos e Questionários
2.
Cancer Immunol Res ; 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38558120

RESUMO

Small cell lung cancer (SCLC) is an aggressive cancer for which immune checkpoint inhibitors (ICIs) have had only limited success. Bispecific T-cell engagers are promising therapeutic alternatives for ICI-resistant tumors, but not all SCLC patients are responsive. Herein, to integrate CD137 costimulatory function into a T-cell engager format and thereby augment therapeutic efficacy, we generated a CD3/CD137 dual-specific Fab and engineered a DLL3-targeted trispecific antibody (DLL3 trispecific). The CD3/CD137 dual-specific Fab was generated to competitively bind to CD3 and CD137 to prevent DLL3-independent cross-linking of CD3 and CD137, which could lead to systemic T-cell activation. We demonstrated that DLL3 trispecific induced better tumor growth control and a marked increase in the number of intratumoral T cells compared to a conventional DLL3-targeted bispecific T-cell engager. These findings suggest that DLL3 trispecific can exert potent efficacy by inducing concurrent CD137 costimulation and provide a promising therapeutic option for SCLC.

3.
Cancer Immunol Res ; : OF1-OF12, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38563577

RESUMO

Small-cell lung cancer (SCLC) is an aggressive cancer for which immune checkpoint inhibitors (ICI) have had only limited success. Bispecific T-cell engagers are promising therapeutic alternatives for ICI-resistant tumors, but not all patients with SCLC are responsive. Herein, to integrate CD137 costimulatory function into a T-cell engager format and thereby augment therapeutic efficacy, we generated a CD3/CD137 dual-specific Fab and engineered a DLL3-targeted trispecific antibody (DLL3 trispecific). The CD3/CD137 dual-specific Fab was generated to competitively bind to CD3 and CD137 to prevent DLL3-independent cross-linking of CD3 and CD137, which could lead to systemic T-cell activation. We demonstrated that DLL3 trispecific induced better tumor growth control and a marked increase in the number of intratumoral T cells compared with a conventional DLL3-targeted bispecific T-cell engager. These findings suggest that DLL3 trispecific can exert potent efficacy by inducing concurrent CD137 costimulation and provide a promising therapeutic option for SCLC.

4.
J Nat Prod ; 87(5): 1376-1383, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38662398

RESUMO

A precursor-directed biosynthesis approach led to the accumulation of seven new neoantimycin derivatives (1-7) from Streptomyces conglobatus RJ2. Structure elucidation was conducted using NMR and HRESIMS analysis, and the absolute configuration was determined by advanced Marfey's method, Mosher's analysis, and ECD analysis. The obtained compounds revealed selective and significant cytotoxicity, specifically against colorectal cancer cells bearing the K-ras mutation, with IC50 values ranging from 40 nM to 3.5 µM.


Assuntos
Streptomyces , Streptomyces/química , Streptomyces/metabolismo , Humanos , Estrutura Molecular , Antineoplásicos/farmacologia , Antineoplásicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Mutação , Ressonância Magnética Nuclear Biomolecular , Compostos Orgânicos
5.
Mol Biol Rep ; 51(1): 70, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38175288

RESUMO

BACKGROUND: The tea tree (Melaleuca alternifolia) is renowned for its production of tea tree oil, an essential oil primarily composed of terpenes extracted from its shoot. MYB transcription factors, which are one of the largest TF families, play a crucial role in regulating primary and secondary metabolite synthesis. However, knowledge of the MYB gene family in M. alternifolia is limited. METHODS AND RESULTS: Here, we conducted a comprehensive genome-wide analysis of MYB genes in M. alternifolia, referred to as MaMYBs, including phylogenetic relationships, structures, promoter regions, and GO annotations. Our findings classified 219 MaMYBs into four subfamilies: one 5R-MYB, four 3R-MYBs, sixty-one MYB-related, and the remaining 153 are all 2R-MYBs. Seven genes (MYB189, MYB146, MYB44, MYB29, MYB175, MYB162, and MYB160) were linked to terpenoid synthesis based on GO annotation. Phylogenetic analysis with Arabidopsis homologous MYB genes suggested that MYB193 and MYB163 may also be involved in terpenoid synthesis. Additionally, through correlation analysis of gene expression and metabolite content, we identified 42 MYB genes associated with metabolite content. CONCLUSION: The results provide valuable insights into the importance of MYB transcription factors in essential oil production in M. alternifolia. These findings lay the groundwork for a better understanding of the MYB regulatory network and the development of novel strategies to enhance essential oil synthesis in M. alternifolia.


Assuntos
Arabidopsis , Melaleuca , Óleos Voláteis , Genes myb , Melaleuca/genética , Filogenia , Chás Medicinais , Fatores de Transcrição/genética , Terpenos
6.
Angew Chem Int Ed Engl ; 63(2): e202315302, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38009464

RESUMO

Nitrogen-doped cavities are pervasive in graphenic materials, and represent key sites for catalytic and electrochemical activity. However, their structures are generally heterogeneous. In this study, we present the synthesis of a well-defined molecular cutout of graphene featuring N-doped cavity. The graphitization of a macrocyclic pyridinic precursor was achieved through photochemical cyclodehydrochlorination. In comparison to its counterpart with pyridinic nitrogen at the edges, the pyridinic nitrogen atoms in this nanographene cavity exhibit significantly reduced basicity and selective binding to Ag+ ion. Analysis of the protonation and coordination equilibria revealed that the tri-N-doped cavity binds three protons, but only one Ag+ ion. These distinct protonation and coordination behaviors clearly illustrate the space confinement effect imparted by the cavities.

7.
J Plant Physiol ; 289: 154080, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37699261

RESUMO

Modification of lipid composition in the mesocarp tissue of oil palm involves genetic manipulation of multiple genes. More than one mesocarp-preferential promoter is necessary for the expression of individual transgenes in the same plant to obviate transcriptional gene silencing. This study aimed to identify genes that are preferentially expressed in the mesocarp tissue and characterize selected candidate mesocarp-preferential promoters. Ten transcripts that were preferentially expressed in the mesocarp tissue were identified from the analysis of 82 transcriptome datasets of 12 different oil palm tissues. The expression of two candidate genes, MSP-C1 and MSP-C6, was verified to be preferentially expressed in the mesocarp tissues and shown to have a low expression level in non-mesocarp tissues by reverse transcription quantitative real-time PCR (RT-qPCR). MSP-C6 promoter fragments of different lengths were transformed into tomato plants for further characterization. Both unripe and ripe fruits of transgenic tomato plants transformed with a construct harboring the MSP-C6-F1 (2014 bp) promoter were shown to have high beta-glucuronidase (GUS) activities. The findings of this study suggest the potential applications of the MSP-C6 promoter as a molecular tool for genetic engineering of novel traits in fruit crops.


Assuntos
Frutas , Solanum lycopersicum , Regiões Promotoras Genéticas/genética , Transgenes , Frutas/genética , Frutas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Engenharia Genética , Regulação da Expressão Gênica de Plantas/genética , Glucuronidase/genética , Glucuronidase/metabolismo
8.
Plant Dis ; 2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37709725

RESUMO

Coconut (Cocos nucifera) is a high economic value cash crop in Malaysia. In December 2021, irregular spots with dotted rust-like appearance were observed mainly on the tip of the leaves of MATAG variety coconut seedlings at the nursery in Perak state. More than 90% of the coconut seedlings surveyed were infected with leaf spot symptoms. These symptoms could bring huge economic losses due to the downgrade value of the seedlings. 15 symptomatic leaves were obtained from the nursery, 10 mm2 of cut leaves were disinfected with 10% sodium hypochlorite for 10 minutes and rinsed with sterile distilled water before plated on potato dextrose agar (PDA). A total of 4 single-spore isolates were obtained and were observed morphologically. The isolates had white cotton-like appearance with undulate edge. Black acervuli were seen after 7 days of incubation at 26 °C. The conidia were fusiform and contained five cells with four septate and three versicolor cells in between the apical and basal cell. The conidia were 17.2 µm long and 5.9 µm wide (n=30). Conidia consisted of two to three apical appendages and one basal appendage. These morphological characters were consistent with the original description of Neopestalotiopsis clavispora (Santos et al., 2019; Abbas et al., 2022). Species identification was done by amplifying internal transcribed spacer (ITS) region using primers ITS 4 and ITS 5 (White et al., 1990) and beta-tubulin (TUB2) using primers Bt2a and Bt2b (Glass & Donaldson et al., 1995) of the representative isolate LKR1, then sequenced. The 488 bp ITS and 409 bp TUB2 sequences were deposited in GenBank under the accession numbers ON844193 and OP004810, respectively. Isolate LKR1 shares 99.8% identity with the ITS sequence (MH860736.1) of the reference pathogenic N. clavispora strain CBS:447.73 and 100% identity with the TUB2 sequence (KM199443.1) of the reference pathogenic N. clavispora strain CBS 447.73. The phylogenetic analysis confirmed that the isolate LKR1 belonged to N. clavispora when a supported clade is formed with 98% and 94% bootstrap support for ITS and TUB2 respectively with other related N. clavispora. Pathogenicity test was conducted by using five replicates of 8 month old seedlings, they were incubated under greenhouse condition and were watered daily. The leaves of the seedlings were injured with sterile needles and were sprayed with conidial suspension (1 x 10^6 conidia/ml). The control plants were also injured but sprayed with sterile distilled water. After a month, signature symptoms of spots on the leaves appear but none on the control seedling. N. clavispora was successfully re-isolated only from the inoculated symptomatic leaves and identified morphologically. No fungus was re-isolated from the control seedlings. The result was consistent even after repeating the test one more time. N. clavispora has been reported causing leaf spot on Macadamia integrifolia (Santos et al., 2019), Phoenix dactylifera L. (Basavand et al., 2020) and Musa acuminata (Qi et al., 2022). N. clavispora has also been reported causing rust-like appearance of leaves on strawberry (Fragaria × ananassa Duch.) (Obregón et al., 2018). To our knowledge, this is the first report of N. clavispora causing leaf spot disease on coconut seedlings in Malaysia. Through the identification of N. clavispora as the causal agent of leaf spot on coconut, this can help coconut growers to tackle the disease problem earlier thus, preventing the disease from spreading until the adult phase.

9.
Artigo em Inglês | MEDLINE | ID: mdl-37755545

RESUMO

The prevalence of type 2 diabetes mellitus (T2DM) is alarming because it is always linked to the increase in chronic diseases, mortality, and socioeconomic burden. Water kefir has a wide range of functional and probiotic characteristics attributed to the microorganisms present in the kefir grains. The present study aims to evaluate the in vivo anti-diabetic potential of the isolated Lactobacillus paracasei from Malaysian water kefir grains (MWKG) which was reported to have excellent probiotic properties and high antioxidant activities as reported previously. High-fat diet/streptozotocin (HFD/STZ) induction was used to obtain a T2DM model followed by treatment with the isolated L. paracasei from MWKG. The levels of glucose, insulin, and in vivo liver antioxidants were quantified after 14 weeks. Gene expression analysis of the liver was also carried out using microarray analysis, and several genes were selected for validation using quantitative real-time PCR. Insulin tolerance test demonstrated that the L. paracasei isolated from the MWKG alleviated T2DM by improving the area under the curve of the insulin tolerance test whereby low-dose and high-dose concentrations treated groups showed 2424.50 ± 437.02 mmol/L·min and 2017.50 ± 347.09 mmol/L·min, respectively, compared to untreated diabetic mice which was 3884.50 ± 39.36 mmol/L·min. Additionally, treatment with the isolated L. paracasei from MWKG regulated the expression of several genes related to glucose homeostasis and lipid metabolism in diabetic mice. These results suggested that the isolated L. paracasei from MWKG could be a potential dietary supplement for T2DM.

10.
World J Microbiol Biotechnol ; 39(5): 123, 2023 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-36934342

RESUMO

In today's fast-shifting climate change scenario, crops are exposed to environmental pressures, abiotic and biotic stress. Hence, these will affect the production of agricultural products and give rise to a worldwide economic crisis. The increase in world population has exacerbated the situation with increasing food demand. The use of chemical agents is no longer recommended due to adverse effects towards the environment and health. Biocontrol agents (BCAs) and biostimulants, are feasible options for dealing with yield losses induced by plant stresses, which are becoming more intense due to climate change. BCAs and biostimulants have been recommended due to their dual action in reducing both stresses simultaneously. Although protection against biotic stresses falls outside the generally accepted definition of biostimulant, some microbial and non-microbial biostimulants possess the biocontrol function, which helps reduce biotic pressure on crops. The application of synergisms using BCAs and biostimulants to control crop stresses is rarely explored. Currently, a combined application using both agents offer a great alternative to increase the yield and growth of crops while managing stresses. This article provides an overview of crop stresses and plant stress responses, a general knowledge on synergism, mathematical modelling used for synergy evaluation and type of in vitro and in vivo synergy testing, as well as the application of synergism using BCAs and biostimulants in reducing crop stresses. This review will facilitate an understanding of the combined effect of both agents on improving crop yield and growth and reducing stress while also providing an eco-friendly alternative to agroecosystems.


Assuntos
Agricultura , Estresse Fisiológico , Produtos Agrícolas , Mudança Climática
11.
J Nat Prod ; 86(4): 994-1002, 2023 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-36947873

RESUMO

Seven new 18-residue peptaibols, trichorzins A-G (1-7), were isolated from the sponge-derived fungus Trichoderma sp. GXIMD 01001. Their structures and configurations were characterized by a comprehensive interpretation of the NMR spectroscopic data, MS/MS fragmentation, Marfey's method, and ECD analysis. The general sequences of trichorzins A-G are as follows: Ac-Aib1-Ala/Ser2-Ala3-Aib/Iva4-Iva5-Gln6-Aib/Iva7-Val/allo-Ile8-Aib9-Gly10-Leu11-Aib12-Pro13-Leu14-Aib15-Aib16-Gln17-Trpol/Pheol18. The obtained compounds were assessed for their potential antiproliferative and antimicrobial activities. All obtained compounds did not show potent antibacterial activity but exhibited significant cytotoxicity, with the lowest IC50 values at 0.46-4.7 µM against four human carcinoma cell lines.


Assuntos
Peptaibols , Trichoderma , Humanos , Peptaibols/química , Trichoderma/química , Espectrometria de Massas em Tandem , Antibacterianos/química
12.
J Am Chem Soc ; 145(5): 2815-2821, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36705468

RESUMO

The synthesis of well-defined nanocarbon multilayers, beyond the bilayer structure, is still a challenging goal. Herein, two trilayer nanographenes were synthesized by covalently linking nanographene layers through helicene bridges. The structural characterization of the trilayer nanographenes revealed a compact trilayer-stacked architecture. The introduction of a furan ring into the helicene linker modulates the interlayer overlap and π-conjugation of the trilayer nanographenes, enabling the tuning of the interlayer coupling, as demonstrated by optical, electrochemical, and theoretical analyses. Both synthesized trilayer nanographenes are rigid chiral nanocarbons and show a chirality transfer from the helicene moiety to the stacked nanographene layers. These helical trilayer nanographenes reported here represent the covalently linked multilayer nanographenes rather than bilayer ones, showing the tunable multilayer stacking structure.

13.
Mol Biol Rep ; 50(2): 1545-1552, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36513867

RESUMO

BACKGROUND: Melaleuca alternifolia is a commercially important medicinal tea tree native to Australia. Tea tree oil, the essential oil distilled from its branches and leaves, has broad-spectrum germicidal activity and is highly valued in the pharmaceutical and cosmetic industries. Thus, the study of genome, which can provide reference for the investigation of genes involved in terpinen-4-ol biosynthesis, is quite crucial for improving the productivity of Tea tree oil. METHODS AND RESULTS: In our study, the next-generation sequencing was used to investigate the whole genome of Melaleuca alternifolia. About 114 Gb high quality sequence data were obtained and assembled into 1,838,159 scafolds with an N50 length of 1021 bp. The assembled genome size is about 595 Mb, twice of that predicted by flow cytometer (300 Mb) and k-mer analysis (345 Mb). Benchmarking Universal Single-Copy Orthologs analyses indicated that only 11.3% of the conserved single-copy genes were miss. Repetitive regions cover over 40.43% of the genome. A total of 44,369 protein-coding genes were predicted and annotated against Nr, Swissprot, Refseq, COG, KOG, and KEGG database. Among these genes, 32,909 and 16,241 genes were functionally annotated in Nr and KEGG, respectively. Moreover, 29,411 and 14,435 genes were functionally annotated in COG and KOG. Additionally, 457,661 simple sequence repeats and 1109 transcription factors (TFs) form 67 TF families were identified in the assembled genome. CONCLUSION: Our findings provide a draft genome sequencing of M. alternifolia which can act as a reference for the deep sequencing strategies, and are useful for future functional and comparative genomics analyses.


Assuntos
Melaleuca , Óleos Voláteis , Óleo de Melaleuca , Humanos , Melaleuca/genética , Árvores , Chás Medicinais
14.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-988516

RESUMO

Aims@#This study was designed to examine the enzyme activity of selected virulent isolates of Ganoderma boninense against oil palm. In a separate in vitro assessment, the effect of macronutrients on the mycelial growth of four selected Ganoderma spp. was also tested.@*Methodology and results@#The study involved a comparison of ligninolytic enzymes; lignin peroxidase (LiP), manganese peroxidase (MnP) and laccase (Lac) profiling of eight isolates of G. boninense, categorized into three levels of aggressiveness, with two control isolates (G. boninense PER71 and G. tornatum NPG1) using solid-state fermentation (SSF). The Principal Component Analysis (PCA) revealed that the isolates had a significant production of ligninolytic enzymes on day 80. The most aggressive isolate, ET61 had the highest Lac production. As for the macronutrient test, mycelial growth for all the Ganoderma spp. was highly affected by potassium (K).@*Conclusion, significance and impact of study@#The findings of this study elucidated the characteristics of G. boninense in relation to enzyme production for the degradation of oil palm lignin and the identification of essential nutrients involved in the survival and growth of Ganoderma spp. The study provides vital information on the pathogenic characteristics of G. boninense isolates involved in biomass degradation along with the role of nutrient on the growth of Ganoderma spp. that may influence basal stem rot (BSR) management in the field.


Assuntos
Enzimas , Ganoderma , Óleo de Palmeira
15.
Angew Chem Int Ed Engl ; 61(38): e202210268, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-35899409

RESUMO

Nanographenes are inclined to assemble into stacked columnar structures that are stabilized by π-π interactions, whereas other supramolecular structures of nanographenes, such as prisms and cages, are rarely investigated. Herein, a diazananographene was synthesized, and then assembled with a coordination unit, thereby producing a triangular metallaprism. After adding C60 or C70 , the triangular metallaprism was transformed into a square tetramer, which encapsulated a pair of C60 or C70 molecules. The formed host-guest complex demonstrated efficient energy transfer from the diazananographene shell to the C60 cores. The emission intensity of the capsulated C60 was enhanced remarkably, compared with free C60 , due to an increased quantum yield and optical absorption coefficient. This work demonstrates the versatility of nanographene-based supramolecular architectures beyond columnar stacking and their ability to enhance the emission of otherwise non-emissive fullerene.

16.
BMC Genomics ; 23(1): 164, 2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35219299

RESUMO

BACKGROUND: The ability of plants to withstand and thrive in an adverse environment is crucial to ensure their survivability and yield performance. The WRKY transcription factors (TFs) have crucial roles in plant growth, development and stress response, particularly drought stress. In oil palm, drought is recognized as one of the major yield limiting factors. However, the roles of WRKY TFs in the drought response of oil palm is unclear. RESULTS: Herein, we studied the transcriptome of drought treated oil palm leaf and identified 40 differentially expressed genes (DEGs) of WRKY TFs, of which 32 DEGs were upregulated and 8 DEGs were downregulated in response to drought stress in oil palm. They were categorized into Groups I to IV based on the numbers of WRKY domain and the structural difference in the zinc finger domain. Multiple stress- and hormone-responsive cis-regulatory elements were detected in the drought responsive oil palm EgWRKY (Dro-EgWRKY) genes. Fourteen of the 15 selected oil palm WRKY (EgWRKY) genes demonstrated a tissue-specific expression profile except for EgWRKY28 (Group I), which was expressed in all tissues tested. The expression levels of 15 candidate EgWRKYs were upregulated upon salinity and heat treatments, while several genes were also inducible by abscisic acid, methyl jasmonate, salicylic acid and hydrogen peroxide treatments. Members of the Group III WRKY TFs including EgWRKY07, 26, 40, 52, 59, 73 and 81 displayed multiple roles in drought- and salinity-response under the modulation of phytohormones. CONCLUSIONS: EgWRKY TFs of oil palm are involved in phytohormones and abiotic stress responses including drought, salinity and heat. EgWRKY07, 26, 59 and 81 from Group III maybe important regulators in modulating responses of different abiotic stresses. Further functional analysis is required to understand the underlying mechanism of WRKY TFs in the regulatory network of drought stress.


Assuntos
Arecaceae , Secas , Regulação da Expressão Gênica de Plantas , Hormônios , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
17.
Carbohydr Polym ; 277: 118764, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34893214

RESUMO

Sulphated polysaccharides (SPs) are carbohydrate macromolecules with sulphate esters that are found among marine algae, seagrasses, mangroves and some terrestrial plants. The sulphate concentration in the ocean (28 mM) since ancient time could have driven the production of SPs in marine algae. SPs have a gelatinous property that can protect marine algae against desiccation and salinity stress. Agar and carrageenan are red algal SPs that are widely used as gelling agents in the food and pharmaceutical industries. The information on the SPs from freshwater and land plants are limited. In this review, we reviewed the taxonomic distribution and composition of SPs in different photosynthetic lineages, and explored the association of SP production in these diversified photosynthetic organisms with evolution history and environmental stresses. We also reviewed the genes/proteins involved in SP biosynthesis. Insights into SP biosynthetic machinery may shed light on the evolution that accompanied adaptation to life on earth.


Assuntos
Polissacarídeos/biossíntese , Sulfatos/metabolismo , Embriófitas/química , Embriófitas/metabolismo , Água Doce/química , Processos Fotoquímicos , Polissacarídeos/química , Sulfatos/química
18.
Sci Rep ; 11(1): 16330, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34381084

RESUMO

Basal stem rot (BSR) of oil palm is a disastrous disease caused by a white-rot fungus Ganoderma boninense Pat. Non-ribosomal peptides (NRPs) synthesized by non-ribosomal peptide synthetases (NRPSs) are a group of secondary metabolites that act as fungal virulent factors during pathogenesis in the host. In this study, we aimed to isolate NRPS gene of G. boninense strain UPMGB001 and investigate the role of this gene during G. boninense-oil palm interaction. The isolated NRPS DNA fragment of 8322 bp was used to predict the putative peptide sequence of different domains and showed similarity with G. sinense (85%) at conserved motifs of three main NRPS domains. Phylogenetic analysis of NRPS peptide sequences demonstrated that NRPS of G. boninense belongs to the type VI siderophore family. The roots of 6-month-old oil palm seedlings were artificially inoculated for studying NRPS gene expression and disease severity in the greenhouse. The correlation between high disease severity (50%) and high expression (67-fold) of G. boninense NRPS gene at 4 months after inoculation and above indicated that this gene played a significant role in the advancement of BSR disease. Overall, these findings increase our knowledge on the gene structure of NRPS in G. boninense and its involvement in BSR pathogenesis as an effector gene.


Assuntos
Ganoderma/genética , Ganoderma/metabolismo , Óleo de Palmeira/metabolismo , Peptídeo Sintases/genética , Peptídeo Sintases/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , DNA de Plantas/genética , Genes de Plantas/genética , Filogenia , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Plântula/genética , Plântula/metabolismo
19.
Biosci Trends ; 15(2): 129-131, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33776019

RESUMO

During the COVID-19 pandemic, frontline nurses have faced extraordinary personal and professional challenges. These challenges have had mental health consequences, and concerning reports of burnout have emerged globally. We conducted a cross-sectional survey at a designated COVID-19 hospital in Shanghai at the peak of the pandemic, i.e. about 2 months after the onset of the outbreak from February to April 2020. Findings revealed burnout in 6.85% of nurses. Of 336 respondents, 87 (25.89%) had a high level of emotional exhaustion, 61 (18.15%) had a high level of depersonalization, and 100 (29.76%) had a low level of personal accomplishment. Burnout can be prevented by offering more support from families and supervisors, paying attention to health monitoring and personal protection, and creating a rational human resource allocation and shift management system. Specific training on infection control and self-protection, mental health guidance, and stress coping techniques must be implemented. As the current health crisis ultimately abates, moving the focus from mental health issues to public health issues, more attention and support at the national and organizational levels are needed to reduce occupational discrimination, nurse autonomy and status need to be promoted, and public health emergency teams need to be created. A positive and fair working environment is essential to effective healthcare delivery.


Assuntos
Esgotamento Profissional/enfermagem , Tratamento Farmacológico da COVID-19 , COVID-19/enfermagem , Recursos Humanos de Enfermagem/psicologia , Pandemias , SARS-CoV-2 , Esgotamento Profissional/epidemiologia , Esgotamento Profissional/prevenção & controle , COVID-19/epidemiologia , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Saúde Mental , Saúde Pública , Inquéritos e Questionários
20.
BMC Genom Data ; 22(1): 6, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33568046

RESUMO

BACKGROUND: Phosphorus (P), in its orthophosphate form (Pi) is an essential macronutrient for oil palm early growth development in which Pi deficiency could later on be reflected in lower biomass production. Application of phosphate rock, a non-renewable resource has been the common practice to increase Pi accessibility and maintain crop productivity in Malaysia. However, high fixation rate of Pi in the native acidic tropical soils has led to excessive utilization of P fertilizers. This has caused serious environmental pollutions and cost increment. Even so, the Pi deficiency response mechanism in oil palm as one of the basic prerequisites for crop improvement remains largely unknown. RESULTS: Using total RNA extracted from young roots as template, we performed a comparative transcriptome analysis on oil palm responding to 14d and 28d of Pi deprivation treatment and under adequate Pi supply. By using Illumina HiSeq4000 platform, RNA-Seq analysis was successfully conducted on 12 paired-end RNA-Seq libraries and generated more than 1.2 billion of clean reads in total. Transcript abundance estimated by fragments per kilobase per million fragments (FPKM) and differential expression analysis revealed 36 and 252 genes that are differentially regulated in Pi-starved roots at 14d and 28d, respectively. Genes possibly involved in regulating Pi homeostasis, nutrient uptake and transport, hormonal signaling and gene transcription were found among the differentially expressed genes. CONCLUSIONS: Our results showed that the molecular response mechanism underlying Pi starvation in oil palm is complexed and involved multilevel regulation of various sensing and signaling components. This contribution would generate valuable genomic resources in the effort to develop oil palm planting materials that possess Pi-use efficient trait through molecular manipulation and breeding programs.


Assuntos
Arecaceae/genética , Arecaceae/metabolismo , Perfilação da Expressão Gênica , Fósforo/deficiência , Raízes de Plantas/metabolismo , Transcriptoma , Regulação da Expressão Gênica de Plantas , Homeostase , Raízes de Plantas/genética , RNA-Seq
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