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1.
Sci Total Environ ; : 172561, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38641104

RESUMO

Environmental stressors such as salinity fluctuations can significantly impact the ecological dynamics of mussel beds. The present study evaluated the influence of hyposalinity stress on the detachment and survival of attached mussels by simulating a mussel farming model in a laboratory setting. Byssus production and mechanical properties of thread in response to varying salinity levels were assessed, and histological sections of the mussel foot were analyzed to identify the changes in the byssus secretory gland area. The results showed that hyposalinity stress (20 and 15 psu) led to a significant decrease in mussel byssus secretion, delayed initiation of new byssus production, and reduced plaque adhesion strength and breaking force of byssal threads compared to the control (30 psu) (p < 0.05). The complete suppression of byssal thread secretion in mussels under salinity conditions of 10 and 5 psu, leading to lethality, indicates the presence of a blockade in byssus secretion when mussels are subjected to significant physiological stressors. Histological analysis further demonstrated a decrease in the percentage of foot secretory gland areas in mussels exposed to low salinities. However, contrary to expectations, the study found that mussels did not exhibit marked detachment from ropes in response to the reduced salinity levels during one week of exposure. Hyposalinity stress exposure reduced the byssal secretion capacity and the mechanical properties of threads, which could be a cause for the detachment of suspension-cultured mussels. These results highlight the vulnerability of mussels to hyposalinity stress, which significantly affects their byssus mechanical performance.

4.
Protein Expr Purif ; 218: 106449, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38423157

RESUMO

We previously showed that the root cause of low Protein A step yield observed for certain antibodies/Fc-fusions is the presence of non-binding aggregates in cell culture harvest. A pre-assumption for the above conclusion is that the aggregates, while do not bind to the preparative Protein A column, can bind to the analytical Protein A-high performance liquid chromatography (HPLC) column used for titer measurement. In the current work, using materials from a previous case with the low yield issue, we confirmed that non-binding aggregates in preparative Protein A flow-through can indeed bind to the analytical Protein A column. In addition, we showed that this discrepancy is mainly due to the different loading densities applied under these two circumstances. We also demonstrated that aggregate bound to the analytical Protein A column slightly stronger than the monomer, as it exhibited a longer retention time. In summary, the current study not only confirmed that non-binding aggregates detected in the preparative Protein A flow-through bind to the Protein A-HPLC column and contribute to the measured titer of culture harvest but also unravelled the reason for different binding behaviors exhibited by antibody aggregates towards preparative and analytical Protein A columns.


Assuntos
Anticorpos , Fragmentos Fc das Imunoglobulinas , Cromatografia Líquida de Alta Pressão/métodos , Espaço Extracelular
5.
Environ Sci Pollut Res Int ; 31(15): 22380-22394, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38407712

RESUMO

As one of the most significant contaminants and stressors in aquaculture systems, ammonia adversely jeopardizes the health of aquatic animals. Ammonia exposure affects the development, metabolism, and survival of shellfish. However, the responses of the innate immune and antioxidant systems and apoptosis in shellfish under ammonia stress have rarely been reported. In this study, razor clams (Sinonovacula constricta) were exposed to different concentrations of non-ion ammonia (0.25 mg/L, 2.5 mg/L) for 72 h and then placed in ammonia-free seawater for 72 h for recovery. The immune responses induced by ammonia stress on razor clams were investigated by antioxidant enzyme activities and degree of apoptosis in digestive gland and gill tissues at different time points. The results showed that exposure to a high concentration of ammonia greatly disrupted the antioxidant system of the razor clam by exacerbating the accumulation of reactive oxygen species ( O 2 - , H2O2) and disordering the activities of antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase), and the level of activity remained at a significantly high level after recovering for 72 h (P < 0.05). In addition, there were significant differences (P < 0.05) in the expression of key genes (Caspase 7, Cyt-c, Bcl-2, and Bax) in the mitochondrial apoptotic pathway in the digestive glands and gills of razor clams as a result of ammonia stress and were unable to return to normal levels after 72 h of recovery. TUNEL staining indicated that apoptosis was more pronounced in gills, showing a dose and time-dependent pattern. As to the results, ammonia exposure leads to the activation of innate immunity in razor clams, disrupts the antioxidant system, and activates the mitochondrial pathway of apoptosis. This is important for comprehending the mechanism underlying the aquatic toxicity resulting from ammonia in shellfish.


Assuntos
Antioxidantes , Bivalves , Animais , Antioxidantes/metabolismo , Amônia/toxicidade , Amônia/metabolismo , Peróxido de Hidrogênio/metabolismo , Estresse Oxidativo , Bivalves/metabolismo , Apoptose
6.
Artigo em Inglês | MEDLINE | ID: mdl-38408517

RESUMO

Euryhaline organisms can accumulate organic osmolytes to maintain osmotic balance between their internal and external environments. Proline is a pivotal organic small molecule and plays an important role in osmoregulation that enables marine shellfish to tolerate high-salinity conditions. During high-salinity challenge, NAD kinase (NADK) is involved in de novo synthesis of NADP(H) in living organisms, which serves as a reducing agent for the biosynthetic reactions. However, the role of shellfish NADK in proline biosynthesis remains elusive. In this study, we show the modulation of NADK on proline synthesis in the razor clam (Sinonovacula constricta) in response to osmotic stress. Under acute hypersaline conditions, gill tissues exhibited a significant increase in the expression of ScNADK. To elucidate the role of ScNADK in proline biosynthesis, we performed dsRNA interference in the expression of ScNADK in gill tissues to assess proline content and the expression levels of key enzyme genes involved in proline biosynthesis. The results indicate that the knock-down of ScNADK led to a significant decrease in proline content (P<0.01), as well as the expression levels of two proline synthetase genes P5CS and P5CR involved in the glutamate pathway. Razor clams preferred to use ornithine as substrate for proline synthesis when the glutamate pathway is blocked. Exogenous administration of proline greatly improved cell viability and mitigated cell apoptosis in gills. In conclusion, our results demonstrate the important role of ScNADK in augmenting proline production under high-salinity stress, by which the razor clam is able to accommodate salinity variations in the ecological niche.


Assuntos
Bivalves , Fosfotransferases (Aceptor do Grupo Álcool) , Tolerância ao Sal , Animais , Bivalves/metabolismo , Prolina/metabolismo , Glutamatos/metabolismo
7.
Plant Dis ; 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38197883

RESUMO

Belamcanda chinensis (L.) Redouté, a member of the Iridaceae family, is globally well-known for its medicinal value as clearing away heat, detoxifying, detumescence and pain (Qin 2000). In 2021, spots were observed on 40% B. chinensis leaves and about 28 disease index in Wanzhou District (30°32'N; 108°22'E) of Chongqing. Initial symptoms appeared as circular yellow white, sunken spots lesions, and then expanded into irregular lesions, the center of the spots was beige, external layer was light brown and surrounded by yellow halo. Symptomatic leaf tissues (5 × 5 mm) were cut from the infected margin, surface sterilized with 75% ethanol for 1 min, washed with 3% sodium hypochlorite for 3 min, rinsed three times with sterile water, placed on potato dextrose agar (PDA) medium incubated at 25°C for 7 days in the dark, forty isolates with similar morphology were obtained. Three isolates (SG9、SG20 and SG33) was selected for subsequent research. Colonies color changed from beige to light brown color after 14 days on PDA medium. Fungal colonies transformed from beige to brown at the edges after 28 days and light brown on top. Ascomata dark brown, ellipsoidal to globose 116.6 to 253.3 × 89.6 to 172.6 µm in diamensions. Asci stipitate, cylindrical with obtuse ends, and 69.1 to 114.7 × 10.2 to 24.1 µm (n = 30) in size, with eight overlapping linearly biseriate ascospores. Ascospores brown, narrowly fusiform, straight or slightly curved with three transversely septate, slightly constricted at septa, and 9.7 to 12.6 × 27.6 to 32.6 µm (n = 30). These characteristics are consistent with Phaeosphaeria sp. reported by Quaedvlieg et al in 2013. DNA was extracted from representative isolates. The internal transcribed spacer (ITS) region, the large subunit rDNA (LSU), the small subunit rDNA (SSU) and the RNA polymerase II second largest subunit (RPB2) genes were amplified for Polymerase chain reaction (PCR) by used ITS1/ITS4, LR5/LROR, NS1/NS4, and RPB2-5f2/RPB2-7cr primers (White et al. 1990; Vilgalys et al. 1990; Qi M W. et al. 2008; De G. J. et al. 1992). The sequences were submitted to NCBI GenBank: SG-G9 (ITS, OR701701; LSU, OR701699; SSU, OR701700; RPB2, OR738464); SG-G20 (ITS, OQ748032; LSU, OQ780728; SSU, OQ780723; RPB2, OQ779979); SG-G33 (ITS, OQ748033; LSU, OQ780729; SSU, OQ780722; RPB2, OQ779980). A phylogenetic analysis revealed a 99% similarity to the Phaeosphaeria caricicola CBS 603.86 (ITS, KF251182; LSU, GQ387590; SSU, GQ387529; RPB2, KF252189) sequences. Mycelial agar plugs (5-mm diameter) from a 7-day-old PDA culture of a fungal isolate were placed onto pinpricked leaves of three two-year-old B. chinensis plants. While the sterile PDA plugs inoculated in pinpricked leaves of B. chinensis as controls. Inoculated plants were placed in a greenhouse at 25°C and remained 95±1% relative humidity. The inoculated leaves of treatment developed symptoms after 20 days, whereas no symptoms occurred on controls, fulfilling Koch's postulates. The experiments were repeated three times. The fungus was re-isolated and was identical to original isolate by morphologically and molecularly. As far as we know, P. caricicola can cause diseases on carex plants and has been found in Switzerland. This is the first report of P. caricicola causing leaf spot on B. chinensis in China. Along with recording the occurrence of this disease, plant disease management strategies need to be established to reduce losses.

8.
Int J Surg ; 110(1): 53-65, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37851516

RESUMO

OBJECTIVE: Flow diverter stents (FDSs) have attracted interest for intracranial aneurysm (IA) treatment; however, occlusion of side branches and related complications have been reported. This study aimed to investigate the effects of FDSs in IA management when different branches of intracranial arteries are covered. MATERIALS AND METHODS: A cross-sectional study was conducted using PUBMED, Embase, Web of Science, and Cochrane databases to include randomized or nonrandomized comparative-designed studies from January 2000 to August 2022 which reported outcomes of occlusion/narrowing of branches after IA treatment using FDSs. The PRISMA guidelines were used for our report. A random-effects meta-analysis was conducted to pool the outcomes, which included incidence rates of occlusion/narrowing of FDS-covered branches, branch occlusion-related symptoms, obliteration of IAs, and ideal clinical outcomes (modified Rankin Scale score ≤2). RESULTS: The authors identified 57 studies involving 3789 patients with IA managed by FDSs covering different branches. During the median imaging follow-up at 12 months, the IA obliteration rate was satisfactory (>70%) when covering the ophthalmic artery (OA), posterior communicating artery (PComA), anterior choroidal artery (AChoA) or anterior cerebral artery (ACA), but not the middle cerebral artery-M2 segment (MCA-M2; 69.5%; 95% CI: 60.8-77.5%) and posterior inferior cerebellar artery (PICA; 59.1%, 13/22). The overall ideal clinical outcome was observed in 97.4% of patients (95% CI: 95.5-98.9%). Higher rates of occlusion/narrowing of branches were identified when FDSs covered the ACA (66.6%; 95% CI: 45.1-85.3%), PComA (44.3%; 95% CI: 34.2-54.6%), or MCA-M2 (39.2%; 95% CI: 24.5-54.7%); the risks were lower when covering the OA (11.8%; 95% CI: 8.8-15.1%), PICA (6.8%; 95% CI: 1.5-14.5%), and AchoA (0.5%; 95% CI: 0.0-2.9%). The risk of branch occlusion-related complications was low (incidence rate <5%) for each of the six evaluated branches. CONCLUSIONS: Acceptable outcomes were identified following treatment of IAs when FDSs were placed across each of the six studied cerebral arteries. Treatment decisions regarding FDS placement across branch arteries should be made with the risk of complications from branch occlusion in mind.


Assuntos
Procedimentos Endovasculares , Aneurisma Intracraniano , Humanos , Aneurisma Intracraniano/cirurgia , Estudos Transversais , Resultado do Tratamento , Estudos Retrospectivos , Stents , Artérias Cerebrais , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/métodos
9.
Protein Expr Purif ; 215: 106391, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37939750

RESUMO

While purifying a regular monospecific antibody, we found that the Protein A step yield was much lower than expected. Further studies revealed that the antibody formed large-size aggregates that did not bind to the Protein A resin, hence leading to dropped recovery. In an attempt to solve this low yield issue, we found that mildly acidic pH or ammonium sulfate treatment can partially convert the aggregates into monomers. In addition, when acidic pH treated culture harvest was processed by Protein A chromatography, the yield was restored to the normal range, suggesting that the monomers recovered from aggregates regained Protein A binding capability. Thus, low pH treatment of culture harvest can be potentially used as a general approach for improving Protein A step yield in cases where non-binding antibody aggregates are formed through noncovalent interactions.


Assuntos
Anticorpos Monoclonais , Proteína Estafilocócica A , Anticorpos Monoclonais/química , Proteína Estafilocócica A/química , Cromatografia , Concentração de Íons de Hidrogênio
10.
Protein Expr Purif ; 216: 106418, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38141898

RESUMO

For a certain number of mAbs, bispecific antibodies (bsAbs) and Fc-fusion proteins that we worked on, the Protein A capture step experienced low yield (i.e., ∼80%). A previous case study suggested that non-binding aggregate formed in cell culture was the root cause of low Protein A step yield. In the current work, we selected five projects with the low Protein A yield issue to further illustrate this phenomenon. In all cases, existence of non-binding aggregates was confirmed by size-exclusion chromatography-high performance liquid chromatography (SEC-HPLC) analysis of Protein A load and flow-through. In addition, we demonstrated that aggregates failed to bind to Protein A resin mainly due to their large sizes, which prevented them from entering the resin beads. As the data suggested, SEC-HPLC analysis of Protein A load and flow-through, although not a standard procedure, can provide information that is critical for understanding the unexpected performance of Protein A chromatography in cases like those being presented here. Thus, SEC-HPLC analysis of Protein A load and flow-through is highly recommended for antibodies/Fc-fusions suffering from low Protein A yield.


Assuntos
Anticorpos Biespecíficos , Técnicas de Cultura de Células , Cromatografia Líquida de Alta Pressão , Cromatografia em Gel , Anticorpos Monoclonais/química , Anticorpos Biespecíficos/química , Proteína Estafilocócica A/química
11.
PLoS One ; 18(12): e0295291, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38060597

RESUMO

Aflatoxin B1 (AFB1), with the strong toxicity and carcinogenicity, has been reported to great toxicity to the liver and other organs of animals. It cause huge economic losses to breeding industry, including the aquaculture industry. Chinese mitten crabs (Eriocheir sinensis), as one of important species of freshwater aquaculture in China, are deeply disturbed by it. However, the molecular and metabolic mechanisms of hepatopancreas and ovary in crabs underlying coping ability are still unclear. Hence, we conducted targeted injection experiment with or without AFB1, and comprehensively analyzed transcriptome and metabolomics of hepatopancreas and ovary. As a result, 210 and 250 DEGs were identified in the L-C vs. L-30 m and L-C vs. L-60 m comparison, among which 14 common DEGs were related to six major functional categories, including antibacterial and detoxification, ATP energy reaction, redox reaction, nerve reaction, liver injury repair and immune reaction. A total of 228 and 401 DAMs in the ML-C vs. ML-30 m and ML-C vs. ML-60 m comparison both enriched 12 pathways, with clear functions of cutin, suberine and wax biosynthesis, tyrosine metabolism, purine metabolism, nucleotide metabolism, glycine, serine and threonine metabolism, ABC transporters and tryptophan metabolism. Integrated analysis of metabolomics and transcriptome in hepatopancreas discovered three Co-enriched pathways, including steroid biosynthesis, glycine, serine and threonine metabolism, and sphingolipid metabolism. In summary, the expression levels and functions of related genes and metabolites reveal the regulatory mechanism of Chinese mitten crab (Eriocheir sinensis) adaptability to the Aflatoxin B1, and the findings contribute to a new perspective for understanding Aflatoxin B1 and provide some ideas for dealing with it.


Assuntos
Braquiúros , Transcriptoma , Animais , Feminino , Aflatoxina B1/toxicidade , Aflatoxina B1/metabolismo , Melhoramento Vegetal , Glicina/metabolismo , Serina/metabolismo , Treonina/metabolismo , Braquiúros/genética , Hepatopâncreas/metabolismo
12.
Front Genet ; 14: 1259674, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38046048

RESUMO

Acanthopanax senticosus (Rupr. et Maxim.) Harms is a perennial shrub of the Acanthopanax genus in the Araliaceae family and has a high medicinal value. The application of zinc fertilizer can improve the yield and quality of medicinal materials. However, there are limited reports on approaches to increase the content of medicinal components in A. senticosus, hindering the improvement of its medicinal quality. In this study, A. senticosus was treated with 0.1% (LZn) and 0.4% (HZn) zinc sprayed on the leaf surface. The effects of zinc treatment on the medicinal components in the roots of A. senticosus were analyzed by comprehensive metabolomics and transcriptomics analyses. A total of 316 metabolites were detected, with a prevailing occurrence of terpenoids and phenylpropanoids. We identified metabolites related to the medicinal components that were upregulated after Zn treatment, including 43 terpenoids, 19 phenylpropanoids, eight phenols, and three flavonoids. Combining differential gene expression and K-means analysis, we found 95, 65, and 25 upregulated genes related to phenylpropanoid biosynthesis, terpenoid biosynthesis, and flavonoid biosynthesis, respectively. Under different concentrations of Zn treatment, the upregulated metabolite biosynthesis-related genes and differentially expressed transcription factors varied. Pearson correlation network analysis revealed significant correlations among terpenoids, phenylpropanoids, flavonoids biosynthetic genes, and several transcription factors (ERFs, WRKYs, bHLHs, NACs, and MYBs). This study lays the foundation for understanding the metabolic processes in response to varying levels of zinc foliar spray and provides a theoretical basis for enhancing the efficiency of zinc fertilizer utilization in A. senticosus.

14.
J Orthop Surg Res ; 18(1): 882, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37981677

RESUMO

BACKGROUND: Oblique lumbar interbody fusion (OLIF) has been a popular technique for treating lumbar degenerative diseases. Previous studies have shown its efficiency in lumbar spinal stenosis; yet, only a few studies have investigated its application to severe lumbar spinal stenosis. Herein, we investigated the clinical and radiographic outcome of OLIF with percutaneous pedicle screws in the treatment of severe lumbar spinal stenosis. METHODS: A total of 15 patients who underwent OLIF with percutaneous pedicle screws were retrospectively analysed. All patients were diagnosed with severe lumbar stenosis (Schizas grade C or D) through preoperative magnetic resonance image (MRI) and received OLIF combined with percutaneous pedicle screw surgery. Clinical outcomes, including visual analogue scale (VAS)-back and VAS-leg scores, and Oswestry Disability Index (ODI), as well as mean disc height (DH), mean foraminal height (FH), segmental lumbar lordosis (SLL) and cross-sectional area (CSA) of the spinal canal, were analysed before and after surgery and at the last follow-up. Intraoperative data, complications and fusion rate were also investigated. RESULTS: OLIF combined with percutaneous pedicle screws was performed on 18 segments in 15 patients. Mean follow-up was 23.1 ± 4.6 months (range 15-29 months). VAS-back, VAS-leg, and ODI scores were significantly improved at the last follow-up. DH increased from 8.86 ± 3.06 mm before surgery to 13.31 ± 2.14 mm after; at the last follow-up, DH was 11.69 ± 1.87 mm. FH increased from 17.85 ± 2.26 mm before surgery to 22.09 ± 1.36 mm after; at the last follow-up, FH was 20.41 ± 0.99 mm. CSA of the spinal canal increased from 30.83 ± 21.15 mm2 before surgery to 74.99 ± 33.65 mm2 after the operation and 81.22 ± 35.53 mm2 at the last follow-up. The segmental LL before surgery, after surgery and at last follow-up was 20.27 ± 6.25 degrees, 20.83 ± 6.52 degrees and 19.75 ± 5.87 degrees, respectively. All patients have gained fusion at the last follow-up. CONCLUSION: OLIF with percutaneous pedicle screws could achieve satisfactory clinical and radiographic effects through indirect compression by increasing DH, FH and CSA of the spinal canal in severe lumbar stenosis patients.


Assuntos
Parafusos Pediculares , Fusão Vertebral , Estenose Espinal , Humanos , Estenose Espinal/diagnóstico por imagem , Estenose Espinal/cirurgia , Estudos Retrospectivos , Constrição Patológica , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Resultado do Tratamento , Fusão Vertebral/métodos
15.
Int Ophthalmol ; 43(12): 4911-4919, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37828345

RESUMO

PURPOSE: To investigate the relationship between lens morphology and aberrations in patients with myopia. METHODS: This cross-sectional study included 155 patients with myopia in their right eyes. Spherical power and cylindrical power were achieved by cycloplegic autorefraction. The eyes were divided into three groups for analysis based on their spherical equivalent (SE) values. The 4 mm and 6 mm ocular and internal aberrations were measured using the OPD-scan III. Lens parameters were measured using CASIA2, including lens thickness (LT), radius of anterior/posterior lens surface curvature (RAL/RPL), lens decentration (DEC), and lens tilt (TILT). The differences of lenticular parameters and aberration parameters among the three groups analyzed with ANOVA or Kruskal Wallis test. Pearson correlation or Spearman correlation analysis was performed to evaluate the relationships between the lens parameters and aberrations. A p value < 0.05 indicated statistical significance. RESULTS: The difference in LT, RAL, DEC and TITL among the three groups was statistically significant (p < 0.05). And there were differences among differences in internal high-order aberrations, spherical aberration, and coma aberration(p < 0.05).Spherical power was positively correlated with LT and TITL (p < 0.05) and negatively correlated with DEC, RAL, and RPL (p < 0.05). Cylindrical power was positively correlated with LT (p < 0.05) and negatively correlated DEC (p < 0.05); The lenticular parameters (LT, RAL, DEC, and TILT) were mainly correlated with the ocular and internal spherical aberration. LT and DEC were correlated with ocular and internal higher-order aberrations and coma aberration. CONCLUSION: DEC and LT were the main factors affecting aberrations in patients with myopia.


Assuntos
Cristalino , Miopia , Humanos , Estudos Transversais , Coma , Miopia/diagnóstico , Refração Ocular
16.
Front Microbiol ; 14: 1244239, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37779725

RESUMO

Wolbachia have been developed as a tool for protecting humans from mosquito populations and mosquito-borne diseases. The success of using Wolbachia relies on the facts that Wolbachia are maternally transmitted and that Wolbachia-induced cytoplasmic incompatibility provides a selective advantage to infected over uninfected females, ensuring that Wolbachia rapidly spread through the target pest population. Most transinfected Wolbachia exhibit a strong antiviral response in novel hosts, thus making it an extremely efficient technique. Although Wolbachia has only been used to control mosquitoes so far, great progress has been made in developing Wolbachia-based approaches to protect plants from rice pests and their associated diseases. Here, we synthesize the current knowledge about the important phenotypic effects of Wolbachia used to control mosquito populations and the literature on the interactions between Wolbachia and rice pest planthoppers. Our aim is to link findings from Wolbachia-mediated mosquito control programs to possible applications in planthoppers.

17.
Plant Dis ; 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37822100

RESUMO

Hosta plantaginea is an important horticultural plant with ornamental value and is widely cultivated in China. Since April 2022, leaf rot has been observed in the H. plantaginea plants in Wanzhou District, Chongqing City, China (31º14'58"N, 108º53'25"E), the initial symptom is a yellow and brown lesion on the edge of the leaf, in the late stage, brown blighted tissue caused leaves to curl and abscise. Ten typical diseased leaves were collected, the margins of infected tissues were cut into small pieces (5×5 mm) and were sterilized in 75% Ethanol for 30 s, 3% sodium hypochlorite for 3 min, rinsed three times with sterile water, then dried on sterile filter paper and placed to potato dextrose agar (PDA) medium at 25℃for 4 days. Thirteen isolates with morphological characteristics similar to those of Fusarium spp. (Nelson et al. 1983) were recovered. These isolates had white, pink and yellowish mycelia, two isolates produced irregular colonies, and remaining isolates showed round. Two of each type were selected for intensive study (yz2, yz11, yz9 and yz17). The colony of yz2 reached 62 mm in diameter on PDA medium after seven days, macroconidia were elongated sickle-shaped, 3-5 septa, and 12.92 to 21.49 × 3.42 to 5.90 µm in size, microconidia were oval and measured 5.69 to 12.95 × 3.41 to 9.80 µm in size, conidiophores were whorled and branched, yz9 attained 74 mm in diameter after nine days, macroconidia were curved sickle-shaped and apex cell acuminate, 26.9 to 57.2 × 2.4 to 7.1 µm, 3-5 septa. The microconidia were fusiform, 17.8 to 28.8 × 11.2 to 14.5 µm. Conidiophores variable in length. Genomic DNA was extracted from 7-day-old aerial mycelia of four strains (yz2, yz9, yz11 and yz17). The internal transcribed spacer (ITS) region (White et al. 1990), translation elongation factor (EF-1α) (Cao et al. 2014) and partial RNA polymerase second largest subunit (RPB2) (Wang et al. 2019) gene regions were amplified and multilocus phylogenetic analysis was conducted, their sequences were deposited in NCBI Genbank with the following accession numbers: the strains of yz2 and yz11 with OQ829372 and OR236201 for ITS, OQ848594 and OR282462 for EF-1α, OR492296 and OR492297 for RPB2; yz9 and yz17 with OQ829383 and OR236222 for ITS, OQ848595 and OR282463 for EF-1α, OR492295 and OR492298 for RPB2. The ModelFinder was used to select the best-fit model in PhyloSuite v1.2.2, the Bayesian Inference method (BI) analysis was used to estimate the system relationship, yz9 and yz17 were identified as Fusarium ipomoeae, yz2 and yz11 were identified as Fusarium tricinctum. To verify Koch's postulates, 8 healthy plants of H. plantaginea (two-year-old) grown were rinsed with sterile water, after 5 leaves per plant were stabbed with a sterilized needle, 4 plants were inoculated with conidial suspension (1×106 conidia mL-1), other plants injected with sterile water as control, then placed in a greenhouse maintained with 95% relative humidity at 25 ± 1°C. The symptoms on the leaves were similar to field after inoculation for 7 days, whereas all control leaves remained healthy. The same pathogen was re-isolated and re-identified based on multilocus phylogenetic analysis, fulfilling Koch's postulates. To our knowledge, this is the first report of F. ipomoeae causing leaf rot on H. plantaginea in China. In addition, F. ipomoeae was reported to cause leaf spot in Peanut (Xu et al. 2021), and F. tricinctum can cause fruit rot on navel orange in China (Yang et al. 2023). H. plantaginea as a horticultural plant is popular with some people, but it has long been threatened by Fusarium.spp. The finding can provide a theoretical basis for control leaf rot on H. plantaginea.

19.
Sci Total Environ ; 905: 166834, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37717744

RESUMO

The herbicide ioxynil (IOX) and the synthetic estrogen diethylstilbestrol (DES) are environmentally relevant contaminants that act as endocrine disruptors (EDCs) and have recently been shown to be cardiovascular disruptors in vertebrates. Mussels, Mytilus coruscus, were exposed to low doses of IOX (0.37, 0.037 and 0.0037 mg/L) and DES (0.27, 0.027 and 0.0027 mg/L) via the water and the effect monitored by generating whole animal transcriptomes and measuring cardiac performance and shell growth. One day after IOX (0.37 and 0.037 mg/L) and DES (0.27 and 0.027 mg/L) exposure heart rate frequency was decreased in both groups and 0.27 mg/L DES significantly reduced heart rate frequency with increasing time of exposure (P < 0.05) and no acclimatization occurred. The functional effects were coupled to significant differential expression of genes of the serotonergic synapse pathway and cardiac-related genes at 0.027 mg/L DES, which suggests that impaired heart function may be due to interference with neuroendocrine regulation and direct cardiac effect genes. Multiple genes related to detoxifying xenobiotic substances were up regulated and genes related to immune function were down regulated in the DES group (vs. control), indicating that detoxification processes were enhanced, and the immune response was depressed. In contrast, IOX had a minor disrupting effect at a molecular level. Of note was a significant suppression (P < 0.05) by DES of shell growth in juveniles and lower doses (< 0.0027 mg/L) had a more severe effect. The shell growth depression in 0.0027 mg/L DES-treated juveniles was not accompanied by abundant differential gene expression, suggesting that the effect of 0.0027 mg/L DES on shell growth may be direct. The results obtained in the present study reveal for the first time that IOX and DES may act as neuroendocrine disrupters with a broad spectrum of effects on cardiac performance and shell growth, and that DES exposure had a much more pronounced effect than IOX in a marine bivalve.


Assuntos
Dietilestilbestrol , Mytilus , Animais , Dietilestilbestrol/toxicidade , Dietilestilbestrol/metabolismo , Coração , Nitrilas/metabolismo , Iodobenzenos
20.
Biosystems ; 232: 104989, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37544406

RESUMO

Drug design and optimization are challenging tasks that call for strategic and efficient exploration of the extremely vast search space. Multiple fragmentation strategies have been proposed in the literature to mitigate the complexity of the molecular search space. From an optimization standpoint, drug design can be considered as a multi-objective optimization problem. Deep reinforcement learning (DRL) frameworks have demonstrated encouraging results in the field of drug design. However, the scalability of these frameworks is impeded by substantial training intervals and inefficient use of sample data. In this paper, we (1) examine the core principles of deep or multi-objective RL methods and their applications in molecular design, (2) analyze the performance of a recent multi-objective DRL-based and fragment-based drug design framework, named DeepFMPO, in a real-world application by incorporating optimization of protein-ligand docking affinity with varying numbers of other objectives, and (3) compare this method with a single-objective variant. Through trials, our results indicate that the DeepFMPO framework (with docking score) can achieve success, however, it suffers from training instability. Our findings encourage additional exploration and improvement of the framework. Potential sources of the framework's instability and suggestions of further modifications to stabilize the framework are discussed.


Assuntos
Desenho de Fármacos , Reforço Psicológico
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