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1.
Cell ; 173(4): 989-1002.e13, 2018 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-29606351

RESUMO

Huntington's disease (HD) is characterized by preferential loss of the medium spiny neurons in the striatum. Using CRISPR/Cas9 and somatic nuclear transfer technology, we established a knockin (KI) pig model of HD that endogenously expresses full-length mutant huntingtin (HTT). By breeding this HD pig model, we have successfully obtained F1 and F2 generation KI pigs. Characterization of founder and F1 KI pigs shows consistent movement, behavioral abnormalities, and early death, which are germline transmittable. More importantly, brains of HD KI pig display striking and selective degeneration of striatal medium spiny neurons. Thus, using a large animal model of HD, we demonstrate for the first time that overt and selective neurodegeneration seen in HD patients can be recapitulated by endogenously expressed mutant proteins in large mammals, a finding that also underscores the importance of using large mammals to investigate the pathogenesis of neurodegenerative diseases and their therapeutics.


Assuntos
Proteína Huntingtina/genética , Doença de Huntington/patologia , Animais , Peso Corporal , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/patologia , Sistemas CRISPR-Cas/genética , Córtex Cerebral/patologia , Córtex Cerebral/ultraestrutura , Corpo Estriado/patologia , Corpo Estriado/ultraestrutura , Modelos Animais de Doenças , Proteína Huntingtina/metabolismo , Doença de Huntington/mortalidade , Imageamento por Ressonância Magnética , Neurônios/metabolismo , Neurônios/patologia , Técnicas de Transferência Nuclear , Taxa de Sobrevida , Suínos , Repetições de Trinucleotídeos
2.
Nature ; 619(7969): 293-299, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37286604

RESUMO

Although organic-inorganic hybrid materials have played indispensable roles as mechanical1-4, optical5,6, electronic7,8 and biomedical materials9-11, isolated organic-inorganic hybrid molecules (at present limited to covalent compounds12,13) are seldom used to prepare hybrid materials, owing to the distinct behaviours of organic covalent bonds14 and inorganic ionic bonds15 in molecular construction. Here we integrate typical covalent and ionic bonds within one molecule to create an organic-inorganic hybrid molecule, which can be used for bottom-up syntheses of hybrid materials. A combination of the organic covalent thioctic acid (TA) and the inorganic ionic calcium carbonate oligomer (CCO) through an acid-base reaction provides a TA-CCO hybrid molecule with the representative molecular formula TA2Ca(CaCO3)2. Its dual reactivity involving copolymerization of the organic TA segment and inorganic CCO segment generates the respective covalent and ionic networks. The two networks are interconnected through TA-CCO complexes to form a covalent-ionic bicontinuous structure within the resulting hybrid material, poly(TA-CCO), which unifies paradoxical mechanical properties. The reversible binding of Ca2+-CO32- bonds in the ionic network and S-S bonds in the covalent network ensures material reprocessability with plastic-like mouldability while preserving thermal stability. The coexistence of ceramic-like, rubber-like and plastic-like behaviours within poly(TA-CCO) goes beyond current classifications of materials to generate an 'elastic ceramic plastic'. The bottom-up creation of organic-inorganic hybrid molecules provides a feasible pathway for the molecular engineering of hybrid materials, thereby supplementing the classical methodology used for the manufacture of organic-inorganic hybrid materials.

3.
Nature ; 612(7940): 546-554, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36477541

RESUMO

Insufficient intracellular anabolism is a crucial factor involved in many pathological processes in the body1,2. The anabolism of intracellular substances requires the consumption of sufficient intracellular energy and the production of reducing equivalents. ATP acts as an 'energy currency' for biological processes in cells3,4, and the reduced form of NADPH is a key electron donor that provides reducing power for anabolism5. Under pathological conditions, it is difficult to correct impaired anabolism and to increase insufficient levels of ATP and NADPH to optimum concentrations1,4,6-8. Here we develop an independent and controllable nanosized plant-derived photosynthetic system based on nanothylakoid units (NTUs). To enable cross-species applications, we use a specific mature cell membrane (the chondrocyte membrane (CM)) for camouflage encapsulation. As proof of concept, we demonstrate that these CM-NTUs enter chondrocytes through membrane fusion, avoid lysosome degradation and achieve rapid penetration. Moreover, the CM-NTUs increase intracellular ATP and NADPH levels in situ following exposure to light and improve anabolism in degenerated chondrocytes. They can also systemically correct energy imbalance and restore cellular metabolism to improve cartilage homeostasis and protect against pathological progression of osteoarthritis. Our therapeutic strategy for degenerative diseases is based on a natural photosynthetic system that can controllably enhance cell anabolism by independently providing key energy and metabolic carriers. This study also provides an enhanced understanding of the preparation and application of bioorganisms and composite biomaterials for the treatment of disease.


Assuntos
Condrócitos , Osteoartrite , Fotossíntese , Plantas , Humanos , Trifosfato de Adenosina/metabolismo , Condrócitos/metabolismo , NADP/metabolismo , Osteoartrite/metabolismo , Osteoartrite/patologia , Osteoartrite/terapia , Plantas/metabolismo , Cartilagem/citologia , Cartilagem/metabolismo , Homeostase , Metabolismo Energético , Fusão de Membrana
4.
Nature ; 574(7778): 394-398, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31619792

RESUMO

Inorganic materials have essential roles in society, including in building construction, optical devices, mechanical engineering and as biomaterials1-4. However, the manufacture of inorganic materials is limited by classical crystallization5, which often produces powders rather than monoliths with continuous structures. Several precursors that enable non-classical crystallization-such as pre-nucleation clusters6-8, dense liquid droplets9,10, polymer-induced liquid precursor phases11-13 and nanoparticles14-have been proposed to improve the construction of inorganic materials, but the large-scale application of these precursors in monolith preparations is limited by availability and by practical considerations. Inspired by the processability of polymeric materials that can be manufactured by crosslinking monomers or oligomers15, here we demonstrate the construction of continuously structured inorganic materials by crosslinking ionic oligomers. Using calcium carbonate as a model, we obtain a large quantity of its oligomers (CaCO3)n with controllable molecular weights, in which triethylamine acts as a capping agent to stabilize the oligomers. The removal of triethylamine initiates crosslinking of the (CaCO3)n oligomers, and thus the rapid construction of pure monolithic calcium carbonate and even single crystals with a continuous internal structure. The fluid-like behaviour of the oligomer precursor enables it to be readily processed or moulded into shapes, even for materials with structural complexity and variable morphologies. The material construction strategy that we introduce here arises from a fusion of classic inorganic and polymer chemistry, and uses the same cross-linking process for the manufacture the materials.


Assuntos
Carbonato de Cálcio/química , Química Inorgânica , Ciência dos Materiais/métodos , Polímeros/química
5.
Cancer Cell Int ; 24(1): 64, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336680

RESUMO

BACKGROUND: Esophageal cancer (EC) is a global canker notorious for causing high mortality due to its relentless incidence rate, convoluted with unyielding recurrence and metastasis. However, these intricacies of EC are associated with an immoderate expression of NY-ESO-1 antigen, presenting a lifeline for adoptive T cell therapy. We hypothesized that naturally isolated higher-affinity T cell receptors (TCRs) that bind to NY-ESO-1 would allow T lymphocytes to target EC with a pronounced antitumor response efficacy. Also, targeting TRPV2, which is associated with tumorigenesis in EC, creates an avenue for dual-targeted therapy. We exploited the dual-targeting antitumor efficacy against EC. METHODS: We isolated antigen-specific TCRs (asTCRs) from a naive library constructed with TCRs obtained from enriched cytotoxic T lymphocytes. The robustness of our asTCRs and their TCR-T cell derivatives, Tranilast (TRPV2 inhibitor), and their bivalent treatment were evaluated with prospective cross-reactive human-peptide variants and tumor cells. RESULTS: Our study demonstrated that our naive unenhanced asTCRs and their TCR-Ts perpetuated their cognate HLA-A*02:01/NY-ESO-1(157-165) specificity, killing varying EC cells with higher cytotoxicity compared to the known affinity-enhanced TCR (TCRe) and its wild-type (TCR0) which targets the same NY-ESO-1 antigen. Furthermore, the TCR-Ts and Tranilast bivalent treatment showed superior EC killing compared to any of their monovalent treatments of either TCR-T or Tranilast. CONCLUSION: Our findings suggest that dual-targeted immunotherapy may have a superior antitumor effect. Our study presents a technique to evolve novel, robust, timely therapeutic strategies and interventions for EC and other malignancies.

6.
Arch Gynecol Obstet ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871965

RESUMO

BACKGROUND: Acute abdominal conditions during pregnancy are significant risks to maternal and fetal health, necessitating timely diagnosis and intervention. The choice of surgical approach is a major concern for obstetricians. OBJECTIVE: To evaluate the safety and efficacy of the TU-LESS procedure for acute abdomen in late pregnancy. METHODS: We retrospectively analyzed 12 patients who underwent TU-LESS for acute abdominal conditions in the third trimester from 2020 to 2023. We reviewed medical records for clinical characteristics, surgical interventions, postoperative complications, and pregnancy outcomes. RESULTS: The study included patients with a median age of 27 (range 20-35) and a BMI of 24.33 kg/m2 (range 21.34-31.96). The median gestational age at surgery was 30 weeks (range, 28 + 3-32 + 4 weeks), with surgeries lasting an average of 60 min (range, 30-163 min). Blood loss was 2-20 mL, and the median hospital stay post-surgery was 6 days (range, 2-16 days). There were no significant complications. The median time to delivery after TU-LESS was 56 days (range, 26-66 days), resulting in 8 full-term deliveries, 2 preterm cesareans, and 2 preterm vaginal deliveries. All newborns were healthy, with no fetal losses or neonatal deaths. CONCLUSION: TU-LESS, performed by experienced obstetricians and gynecologists with proper preoperative preparation, is safe and effective for managing acute abdomen in late pregnancy, without the need to delay surgery due to gestational age.

7.
Proc Natl Acad Sci U S A ; 117(7): 3397-3404, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32015117

RESUMO

Organisms use inorganic ions and macromolecules to regulate crystallization from amorphous precursors, endowing natural biominerals with complex morphologies and enhanced properties. The mechanisms by which modifiers enable these shape-preserving transformations are poorly understood. We used in situ liquid-phase transmission electron microscopy to follow the evolution from amorphous calcium carbonate to calcite in the presence of additives. A combination of contrast analysis and infrared spectroscopy shows that Mg ions, which are widely present in seawater and biological fluids, alter the transformation pathway in a concentration-dependent manner. The ions bring excess (structural) water into the amorphous bulk so that a direct transformation is triggered by dehydration in the absence of morphological changes. Molecular dynamics simulations suggest Mg-incorporated water induces structural fluctuations, allowing transformation without the need to nucleate a separate crystal. Thus, the obtained calcite retains the original morphology of the amorphous state, biomimetically achieving the morphological control of crystals seen in biominerals.

8.
Chem Biodivers ; 20(12): e202301512, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37921566

RESUMO

Four new phomalones A-D (1-4), together with five known analogues (5-9) were isolated from the deep-sea-derived fungus Trichobotrys effuse FS522. Their structures of the new compounds established by analysis of their NMR and HR-ESI-MS spectroscopic data, and the absolute configurations of 2 was determined by electronic circular dichroism (ECD) calculations. compounds 4, 6 and 8 substantially inhibited the production of nitric oxide (NO) with IC50 values of 4.64, 13.90, and 34.07 µM.


Assuntos
Ascomicetos , Anti-Inflamatórios/farmacologia , Espectroscopia de Ressonância Magnética/métodos , Estrutura Molecular , Piranos/química , Piranos/farmacologia , Compostos Heterocíclicos com 3 Anéis/química , Compostos Heterocíclicos com 3 Anéis/farmacologia
9.
Bioprocess Biosyst Eng ; 46(9): 1331-1340, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37470869

RESUMO

Chemoenzymatic epoxidation of olefin mediated by lipase is a green and environmentally friendly alternative process. However, the mass transfer barrier and lipase deactivation caused by the traditional organic-water biphasic reaction system have always been the focus of researchers' attention. To overcome these issues, we investigated the effects of reaction temperature and two important substrates (H2O2 and acyl donor) on the epoxidation reaction and interfacial mass transfer. As a result, we determined the optimal reaction conditions: a temperature of 30 °C, 30 wt-% H2O2 as the oxygen source, and 1 M lauric acid as the oxygen carrier. Additionally, by simulating the conditions of shaking flask reactions, we designed a batch reactor and added a metal mesh to effectively block the direct contact between high-concentration hydrogen peroxide and the enzyme. Under these optimal conditions, the epoxidation reaction was carried out for 5 h, and the product yield reached a maximum of 93.2%. Furthermore, after seven repetitive experiments, the lipase still maintained a relative activity of 51.2%.


Assuntos
Peróxido de Hidrogênio , Lipase , Monoterpenos Bicíclicos , Alcenos
10.
Nat Prod Rep ; 39(3): 560-595, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-34623363

RESUMO

Covering 1989 to 2020The mangrove forests are a complex ecosystem occurring at tropical and subtropical intertidal estuarine zones and nourish a diverse group of microorganisms including fungi, actinomycetes, bacteria, cyanobacteria, algae, and protozoa. Among the mangrove microbial community, mangrove associated fungi, as the second-largest ecological group of the marine fungi, not only play an essential role in creating and maintaining this biosphere but also represent a rich source of structurally unique and diverse bioactive secondary metabolites, attracting significant attention of organic chemists and pharmacologists. This review summarizes the discovery relating to the source and characteristics of metabolic products isolated from mangrove-associated fungi over the past thirty years (1989-2020). Its emphasis included 1387 new metabolites from 451 papers, focusing on bioactivity and the unique chemical diversity of these natural products.


Assuntos
Actinobacteria , Produtos Biológicos , Cianobactérias , Produtos Biológicos/química , Cianobactérias/química , Ecossistema , Fungos/metabolismo
11.
Org Biomol Chem ; 20(24): 4900-4904, 2022 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-35694954

RESUMO

Cytospone A (1), a pyrone and isocoumarin hetero-dimer possessing an unprecedented skeleton with a polyoxygen-hetero 6/6/6/6 tetracyclic fused ring system, and three other biosynthetic precursors cytospones B-D (2-4), along with eleven known compounds were purified from Cytospora rhizophorae A761. The deduced structure of cytospone A represents the first family of natural hetero-dimers comprising pyrone and isocoumarin moieties. A plausible biogenetic pathway involving an intriguing Knoevenagel condensation/6π electrocyclization cascade sequence as the key chemical transformation is proposed.


Assuntos
Ascomicetos , Pironas , Ascomicetos/química , Isocumarinas , Estrutura Molecular , Pironas/química
12.
Org Biomol Chem ; 20(21): 4376-4384, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35579069

RESUMO

Three novel phomactin diterpenes neocucurbins A-C (1-3) and their derivatives, neocucurbins D-G (4-7), were isolated from the marine-derived fungus Neocucurbitaria unguis-hominis FS685. Among them, neocucurbins A-C represent the first examples of the phomactin family with an unprecedented skeleton sharing a novel polyoxygen-hetero 5/6/12 or 5/6/13 fused tricyclic ring system; whereas neocucurbins D-G feature a 5/6 fused bicyclic ring system with the opening of the macrocyclic ring, which was found in the phomactin family for the first time. Moreover, spectroscopic data analyses, single-crystal X-ray diffraction experiments, and ECD calculations were conducted to illustrate the absolute configurations of their structures. Furthermore, all seven compounds (1-7) were evaluated for their cytotoxic and antimicrobial activities.


Assuntos
Antineoplásicos , Ascomicetos , Diterpenos , Cristalografia por Raios X , Diterpenos/química , Estrutura Molecular
13.
J Immunol ; 205(9): 2532-2544, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32958688

RESUMO

The NLRP3 inflammasome is associated with a variety of human diseases, including cryopyrin-associated periodic syndrome (CAPS). CAPS is a dominantly inherited disease with NLRP3 missense mutations. Currently, most studies on the NLRP3-inflammasome have been performed with mice, but the activation patterns and the signaling pathways of the mouse NLRP3 inflammasome are not always identical with those in humans. The NLRP3 inflammasome activation in pigs is similar to that in humans. Therefore, pigs with precise NLRP3-point mutations may model human CAPS more accurately. In this study, an NLRP3 gain-of-function pig model carrying a homozygous R259W mutation was generated by combining CRISPR/Cpf1-mediated somatic cell genome editing with nuclear transfer. The newborn NLRP3 R259W homozygous piglets showed early mortality, poor growth, and spontaneous systemic inflammation symptoms, including skin lesion, joint inflammation, severe contracture, and inflammation-mediated multiorgan failure. Severe myocardial fibrosis was also observed. The tissues of inflamed skins and several organs showed significantly increased expressions of NLRP3, Caspase-1, and inflammation-associated cytokines and factors (i.e., IL-1ß, TNF-α, IL-6, and IL-17). Notably, approximately half of the homozygous piglets grew up to adulthood and even gave birth to offspring. Although the F1 heterozygous piglets showed improved survival rate and normal weight gain, 39.1% (nine out of 23) of the piglets died early and exhibited spontaneous systemic inflammation symptoms. In addition, similar to homozygotes, adult heterozygotes showed increased delayed hypersensitivity response. Thus, the NLRP3 R259W pigs are similar to human CAPS and can serve as an ideal animal model to bridge the gap between rodents and humans.


Assuntos
Mutação com Ganho de Função/genética , Inflamação/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Suínos/genética , Animais , Caspase 1/genética , Síndromes Periódicas Associadas à Criopirina/genética , Citocinas/genética , Homozigoto , Humanos , Inflamassomos/genética , Masculino , Pele/metabolismo
14.
J Nat Prod ; 85(8): 1967-1975, 2022 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-35866554

RESUMO

Neocucurbols A-D (1-4) are diterpene derivatives that possess a complex 6/6/5/5/6 polycyclic ring system with a characteristic tetrahedrofuran bridge ring skeleton. Neocucurbols E-H (5-8) are diterpenes that feature a 6/8/6 tricyclic ring system. Their structures were unambiguously determined by detailed spectroscopic analyses, X-ray diffractions studies, and ECD calculations. All compounds (1-8) were evaluated for in vitro antimicrobial and cytotoxic activities.


Assuntos
Anti-Infecciosos , Ascomicetos , Diterpenos , Diterpenos/química , Diterpenos/farmacologia , Estrutura Molecular
15.
Mar Drugs ; 20(12)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36547912

RESUMO

Organosulfur natural products (NPs) refer to the different kinds of small molecular-containing sulfur (S) elements. Sulfur-containing NPs tightly link to the biochemical processes and play an important role in the pharmaceutical industry. The majority of S-containing NPs are generally isolated from Alliaceae plants or bacteria, and those from fungi are still relatively rare. In recent years, an increasing number of S-containing metabolites have been discovered in marine and terrestrial fungi, but there is no comprehensive and targeted review to summarize the studies. In order to make it more straightforward to better grasp the fungal-derived S-containing NPs and understand the particularity of marine S-containing NPs compared to those from terrestrial fungi, we summarized the chemical structures and biological activities of 89 new fungal-derived S-containing metabolites from 1929 when the penicillin was discovered to the present in this current review. The structural and bioactive diversity of these S-containing metabolites were concluded in detail, and the preliminary mechanism for C-S bond formation in fungi was also discussed briefly.


Assuntos
Produtos Biológicos , Fungos , Fungos/química , Plantas/metabolismo , Penicilinas/metabolismo , Produtos Biológicos/química , Bactérias/metabolismo
16.
Gynecol Obstet Invest ; 87(5): 274-285, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36463858

RESUMO

OBJECTIVES: The current systematic review and meta-analysis have shown that specific HLA-G 3' UTR variants are associated with recurrent miscarriage (RM). Our aim was to investigate the relevance of HLA-G 3' UTR polymorphisms with the risk of RM. DESIGN: A combined meta-analysis was implemented in this study. PARTICIPANTS/MATERIALS, SETTING, METHODS: Common electronic databases including PubMed, Embase, Web of Science, China National Knowledge Infrastructure, Cochrane Library, and Google Scholar were used to seek eligible articles up to August 2021. RESULTS: Forty-four eligible articles with 4,467 cases and 3,955 controls were finally enrolled. Our meta-results suggested that 14 bp insertion allele was associated with elevated risk of RM (allelic model: OR = 1.18, 95% CI = 1.07-1.31, p = 0.001). Besides, a significant heterogeneity was observed between studies. Further subgroup analyses based on ethnicity revealed similar positive results in both the Caucasian and Asian subgroups but not in the Middle East subgroup. Moreover, rs1063320 G allele conferred elevated susceptibility to RM in Asian group (allelic model: OR = 1.54, 95% CI = 1.17-2.03, p = 0.002). Additionally, pooled results showed a decreased risk of RM in mothers carrying rs1710 G allele (allelic model: OR = 0.68, 95% CI = 0.55-0.85, p < 0.001) and an increased risk with rs9380142 A allele (allelic model: OR = 1.45, 95% CI = 1.15-1.83, p = 0.002). Further stratified analyses by race showed that these positive results were mainly from the associations observed in Asian populations. LIMITATIONS: The main limitation is that the enrolled number of individuals was relatively small. Thus, the results should be cautiously considered. CONCLUSIONS: Although the current systematic review and meta-analysis have shown that specific HLA-G 3' UTR variants are associated with RM, a high degree of bias is present and further studies are needed to validate this causative effect.


Assuntos
Aborto Habitual , Antígenos HLA-G , Feminino , Humanos , Regiões 3' não Traduzidas/genética , Antígenos HLA-G/genética , Polimorfismo Genético , Aborto Habitual/genética , Alelos , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único
17.
Plant Dis ; 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35156844

RESUMO

In September 2019, anthracnose-like symptoms were observed on fresh avocado fruits cv. "Hass", which were imported from Peru (Mission Produce, Inc.) and purchased at Ganfuyuan store, Guangzhou, China. After being stored for 5 days at room temperature, initial black specks developed into larger brown or black lesions on fruits, and salmon-colored conidial mass in the lesions were observed. To isolate and identify the pathogen, small pieces (5 mm × 5 mm) were excised from the lesion margins of the fruits, which were surface sterilized by 1% NaOCl (1 min), 70% ethanol (30 s) and then washed twice with sterile distilled water (SDW). After sterilization, the tissues were cultured on Potato Dextrose Agar (PDA) to obtain the pure strain NYG. The colonies grown on PDA for 7 days appeared to be cottony, white to pale gray with the presence of a conidial mass. Conidia 11.7-19 × 3.6-6.4 µm (n = 50), hyaline, aseptate, straight and cylindrical with rounded ends, Appressoria 6.2-11.9 × 4.5 × 7.4 µm (n = 50), brown to dark brown in different shapes. Perithecia were thick-walled and globose with a prominent, narrow neck. Asci 31.5-55 × 6-12.5 µm (n = 15), 6-8 spored, clavate to cymbiform. Ascospores 5-18 × 4.5-6 µm (n = 25), hyaline, large guttulate at the centre, slightly curved, rounded ends. Based on the morphological characteristics, the strain NYG was identified as Colletotrichum fructicola (Prihastuti et al. 2009). The identity of the strain was confirmed by means of multi-locus gene sequencing. The genomic DNA was extracted using Ezup Column Fungi Genomic DNA Purification Kit (Sangon Biotech Co., Ltd., China). The internal transcribed spacer (ITS) rDNA region, actin (ACT), chitin synthase (CHS-1), calmodulin (CAL), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) partial genes (Templeton et al. 1999, Carbone et al. 1999) were amplified and sequenced, which were deposited in GenBank (OL413493, OL517766, OL517768, OM141126, OL517767). BLASTN analysis revealed that DNA sequences of the isolate showed 100% identity with those of C. fructicola (MT476840.1, MK208862.1, MZ965245.1, JX009665.1, MN982434.1), respectively. A phylogenetic tree analysis based on the concatenated sequences confirmed the isolate as C. fructicola. Pathogenicity was tested by infecting the fresh healthy avocado fruits with the isolated strain NYG. The fruits were surface sterilized, three unwounded and wounded avocados fruits were respectively inoculated with 10 l of conidial suspension (1×106 conidia/ml) by the drop inoculation method. Control fruits were inoculated with SDW containing Tween 20 (1 µl/ml H2O), respectively. All inoculated fruits were incubated at 25°C in the dark. Anthracnose symptoms were observed on the wounded and unwounded fruits after 3 to 5 days post inoculation, respectively. No symptoms were observed in the control on both the wounded and unwounded fruits. The pathogenicity test was performed in duplicate. The inoculated fungus was reisolated from the infected fruits and confirmed as C. fructicola, thus confirming Koch's postulates. C. fructicola represents an important fungal pathogen in several plantations worldwide (Farr et al. 2020), for example, the avocado fruits in Mexico (Dionicio, et al. 2018) and New Zealand (Hofer et al. 2021). This is the first report of anthracnose caused by C. fructicola on imported avocado fruits in China. The results of this study can not only help establish effective quarantine measures against anthracnose disease for imported avocado fruits in China, but also provide important reference to prevent the spread of this disease on China's domestic avocados.

18.
Int J Therm Sci ; 172: 107371, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34785972

RESUMO

A cooperative control strategy is proposed for the air conditioning (AC) system and ventilation system to reduce the risk of COVID-19 infection and save the energy of the AC system. This strategy integrates the dynamic model of the AC-cabin system, infection risk assessment, model predictive control (MPC) of the thermal environment inside the cabin, and ventilation control that considers passengers' sneezing. Unlike other existing AC system models, the thermal-health model established can describe not only the system performance but also the virus concentration and risk of COVID-19 infection using the Wells-Riley assessment model. Experiments are conducted to verify the prediction accuracy of the AC-cabin model. The results prove that the proposed model can accurately predict the evolution of cabin temperature under different cases. The cooperative control strategy of the AC system integrates the MPC-based refrigeration algorithm for the cabin temperature and intermittent ventilation strategy to reduce the risk of COVID-19 infection. This strategy well balances the control accuracy, energy consumption of the AC system, and the risk of COVID-19 infection, and greatly reduces the infection risk at the expense of a little rise in the energy consumption.

19.
Appl Microbiol Biotechnol ; 105(24): 9219-9230, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34807300

RESUMO

Benzophenones are polyketides with diverse biological activities. Novel cytotoxic benzophenones cytosporaphenones A-C and cytorhizins A-D, which contain a new skeleton, were previously extracted from endophytic fungus Cytospora rhizophorae A761. However, the mechanism for the biosynthesis of these compounds remains unknown. Cytosporaphenone A was assumed to be the precursor for the biosynthesis of cytorhizins A-D. In this study, we sequenced the genome of C. rhizophorae A761 and characterized a benzoate 4-monooxygenase cytochrome P450(BAM). CRISPR/Cas9-mediated gene knockout and overexpression studies in C. rhizophorae confirmed the vital function of BAM in the biosynthesis of cytosporaphenones and cytorhizins. Overexpression of BAM also enhanced the yield of cytosporaphenone A by 1.868 folds. The in vitro function and enzymatic properties of BAM were also described. This study demonstrates the important role of BAM for the biosynthesis of cytosporaphenone A and cytorhizins and is also the first to provide approaches for the CRISPR-Cas9-mediated gene deletion and gene overexpression studies in C. rhizophoarae, thus laying a foundation for the elucidation of the biosynthetic mechanism of cytorhizins and the discovery of new benzophenones mediated by BAM.Key points• The novel bam gene encoding BAM protein in C. rhizophorae was firstly deleted using CRIPSR/Cas9 system.• The in vitro oxidation function of novel BAM protein and enzymatic properties was characterized.• The over expression of bam gene enhanced the yield of cytosporaphone A in C. rhizophorae significantly.


Assuntos
Ascomicetos , Policetídeos , Ascomicetos/genética , Benzofenonas , Sistema Enzimático do Citocromo P-450/genética
20.
Mar Drugs ; 20(1)2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-35049889

RESUMO

Eurothiocins C-H (1-6), six unusual thioester-containing benzoate derivatives, were isolated from the deep-sea-derived fungus Talaromyces indigoticus FS688 together with a known analogue eurothiocin A (7). Their structures were elucidated through spectroscopic analysis and the absolute configurations were determined by X-ray diffraction and ECD calculations. In addition, compound 1 exhibited significant inhibitory activity against α-glucosidase with an IC50 value of 5.4 µM, while compounds 4 and 5 showed moderate effects with IC50 values of 33.6 and 72.1 µM, respectively. A preliminary structure-activity relationship is discussed and a docking analysis was performed.


Assuntos
Benzofuranos/farmacologia , Talaromyces , alfa-Glucosidases/efeitos dos fármacos , Animais , Organismos Aquáticos , Benzofuranos/química , Concentração Inibidora 50 , Relação Estrutura-Atividade , alfa-Glucosidases/metabolismo
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