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1.
Dev Biol ; 512: 57-69, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38750688

RESUMEN

Understanding the developmental processes and signaling pathways involved in larval myogenesis and metamorphosis is crucial for comprehending the life history and adaptive strategies of marine organisms. In this study, we investigated the temporal and spatial patterns of myogenesis in the mussel Mytilus coruscus (Mc), focusing on the emergence and transformation of major muscle groups during different larval stages. We also explored the role of the Hedgehog (Hh) signaling pathway in regulating myogenesis and larval metamorphosis. The results revealed distinct developmental stages characterized by the emergence of specific muscular components, such as velum retractor muscles and anterior adductor muscles, in D-veliger and umbo larvae, which are responsible for the planktonic stage. In the pediveliger stage, posterior ventral, posterior adductor, and foot muscles appeared. After larval metamorphosis, the velum structure and its corresponding retractor muscles degenerate, indicating the transition from planktonic to benthic life. We observed a conserved pattern of larval musculature development and revealed a high degree of conservation across bivalve species, with comparable emergence times during myogenesis. Furthermore, exposure to the Hh signaling inhibitor cyclopamine impaired larval muscle development, reduced larval swimming activity, and inhibited larval metamorphosis in M. coruscus. Cyclopamine-mediated inhibition of Hh signaling led to reduced expression of four key genes within the Hh signaling pathway (McHh, McPtc, McSmo, and McGli) and the striated myosin heavy chain gene (McMHC). It is hypothesised that the abnormal larval muscle development in cyclopamine-treated groups may be an indirect effect due to disrupted McMHC expression. We provide evidence for the first time that cyclopamine treatment inhibited larval metamorphosis in bivalves, highlighting the potential involvement of Hh signaling in mediating larval muscle development and metamorphosis in M. coruscus. The present study provides insights into the dynamic nature of myogenesis and the regulatory role of the Hh signaling pathway during larval development and metamorphosis in M. coruscus. The results obtained in this study contribute to a better understanding of the evolutionary significance of Hh signaling in bivalves and shed light on the mechanisms underlying larval muscle development and metamorphosis in marine invertebrates.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , Proteínas Hedgehog , Larva , Metamorfosis Biológica , Desarrollo de Músculos , Mytilus , Transducción de Señal , Animales , Proteínas Hedgehog/metabolismo , Proteínas Hedgehog/genética , Larva/crecimiento & desarrollo , Larva/metabolismo , Mytilus/crecimiento & desarrollo , Mytilus/metabolismo , Alcaloides de Veratrum/farmacología , Músculos/metabolismo
2.
BMC Bioinformatics ; 25(1): 208, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38849719

RESUMEN

BACKGROUND: Drug design is a challenging and important task that requires the generation of novel and effective molecules that can bind to specific protein targets. Artificial intelligence algorithms have recently showed promising potential to expedite the drug design process. However, existing methods adopt multi-objective approaches which limits the number of objectives. RESULTS: In this paper, we expand this thread of research from the many-objective perspective, by proposing a novel framework that integrates a latent Transformer-based model for molecular generation, with a drug design system that incorporates absorption, distribution, metabolism, excretion, and toxicity prediction, molecular docking, and many-objective metaheuristics. We compared the performance of two latent Transformer models (ReLSO and FragNet) on a molecular generation task and show that ReLSO outperforms FragNet in terms of reconstruction and latent space organization. We then explored six different many-objective metaheuristics based on evolutionary algorithms and particle swarm optimization on a drug design task involving potential drug candidates to human lysophosphatidic acid receptor 1, a cancer-related protein target. CONCLUSION: We show that multi-objective evolutionary algorithm based on dominance and decomposition performs the best in terms of finding molecules that satisfy many objectives, such as high binding affinity and low toxicity, and high drug-likeness. Our framework demonstrates the potential of combining Transformers and many-objective computational intelligence for drug design.


Asunto(s)
Algoritmos , Diseño de Fármacos , Humanos , Simulación del Acoplamiento Molecular , Receptores del Ácido Lisofosfatídico/metabolismo , Receptores del Ácido Lisofosfatídico/química , Inteligencia Artificial
3.
BMC Plant Biol ; 24(1): 551, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38877392

RESUMEN

Alcea rosea L. is a traditional flower with a long cultivation history. It is extensively cultivated in China and is widely planted in green belt parks or used as cut flowers and potted ornamental because of its rich colors and flower shapes. Double-petal A. rosea flowers have a higher aesthetic value compared to single-petal flowers, a phenomenon determined by stamen petaloid. However, the underlying molecular mechanism of this phenomenon is still very unclear. In this study, an RNA-based comparative transcriptomic analysis was performed between the normal petal and stamen petaloid petal of A. rosea. A total of 3,212 differential expressed genes (DEGs), including 2,620 up-regulated DEGs and 592 down-regulated DEGs, were identified from 206,188 unigenes. Numerous DEGs associated with stamen petaloid were identified through GO and KEGG enrichment analysis. Notably, there were 63 DEGs involved in the plant hormone synthesis and signal transduction, including auxin, cytokinin, gibberellin, abscisic acid, ethylene, brassinosteroid, jasmonic acid, and salicylic acid signaling pathway and 56 key transcription factors (TFs), such as MADS-box, bHLH, GRAS, and HSF. The identification of these DEGs provides an important clue for studying the regulation pathway and mechanism of stamen petaloid formation in A. rosea and provides valuable information for molecular plant breeding.


Asunto(s)
Flores , Perfilación de la Expresión Génica , Flores/genética , Flores/crecimiento & desarrollo , Flores/anatomía & histología , Transcriptoma , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Reguladores del Crecimiento de las Plantas/metabolismo
4.
Mol Pharm ; 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38686930

RESUMEN

There has been an increase in the use of molecular probe diagnostic techniques for lung cancer, and magnetic resonance imaging (MRI) offers specific advantages for diagnosing pulmonary carcinoma. Furthermore, advancements in near-infrared II (NIR-II) fluorescence have provided a new method for precise intraoperative tumor resection. However, few probes combine preoperative diagnosis with intraoperative imaging. This study aims to fill this research void by employing a dual-modal probe that targets the epidermal growth factor receptor for MR and NIR-II imaging, enabling the preoperative diagnosis of lung cancer using MRI and precise intraoperative tumor localization using NIR-II with a single probe. The imaging effects and targeting ability of the probe were confirmed in cell lines, mouse models, and clinical samples. The MR signal decreased within 24 h in the patient-derived xenograft mouse model. The average signal-to-background ratio of NIR-II reached 3.98 ± 0.27. The clinical sample also showed a decrease in the T2 signal using MRI, and the NIR-II optical signal-to-background ratio was 3.29. It is expected that this probe can improve the diagnostic rate of lung cancer using MRI and enable precise intraoperative tumor resection using NIR-II.

5.
Protein Expr Purif ; 218: 106449, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38423157

RESUMEN

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.


Asunto(s)
Anticuerpos , Fragmentos Fc de Inmunoglobulinas , Cromatografía Líquida de Alta Presión/métodos , Espacio Extracelular
6.
Protein Expr Purif ; 220: 106503, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38759705

RESUMEN

Protein A affinity chromatography has been widely used for initial product capture in recombinant antibody/Fc-fusion purification. However, in general Protein A lacks the capability of separating aggregates (unless the aggregates are too large to enter the pores of resin beads or have their Protein A binding sites buried, in which case the aggregates do not bind). In the current work, we demonstrated that CaptureSelect FcXP affinity medium exhibited strong aggregate separation capability and effectively removed aggregates under pH or conductivity gradient elution in two bispecific antibody (bsAb) cases. For these two cases, aggregate contents were reduced from >16% and >22% (in the feed) to <1% and <5% (in the eluate) for the first and second bsAbs, respectively. While more case studies are required to further demonstrate FcXP's superiority in aggregate removal, findings from the current study suggest that FcXP can potentially be a better alternative than Protein A for product capture in cases where aggregate content is high.


Asunto(s)
Anticuerpos Biespecíficos , Cromatografía de Afinidad , Proteína Estafilocócica A , Cromatografía de Afinidad/métodos , Anticuerpos Biespecíficos/química , Anticuerpos Biespecíficos/aislamiento & purificación , Proteína Estafilocócica A/química , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/aislamiento & purificación , Proteínas Recombinantes de Fusión/genética , Agregado de Proteínas , Humanos , Fragmentos Fc de Inmunoglobulinas/química , Fragmentos Fc de Inmunoglobulinas/aislamiento & purificación
7.
Protein Expr Purif ; 215: 106391, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37939750

RESUMEN

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.


Asunto(s)
Anticuerpos Monoclonales , Proteína Estafilocócica A , Anticuerpos Monoclonales/química , Proteína Estafilocócica A/química , Cromatografía , Concentración de Iones de Hidrógeno
8.
Protein Expr Purif ; 216: 106418, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38141898

RESUMEN

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.


Asunto(s)
Anticuerpos Biespecíficos , Técnicas de Cultivo de Célula , Cromatografía Líquida de Alta Presión , Cromatografía en Gel , Anticuerpos Monoclonales/química , Anticuerpos Biespecíficos/química , Proteína Estafilocócica A/química
9.
PLoS Comput Biol ; 19(7): e1010774, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37406007

RESUMEN

Typical drug discovery and development processes are costly, time consuming and often biased by expert opinion. Aptamers are short, single-stranded oligonucleotides (RNA/DNA) that bind to target proteins and other types of biomolecules. Compared with small-molecule drugs, aptamers can bind to their targets with high affinity (binding strength) and specificity (uniquely interacting with the target only). The conventional development process for aptamers utilizes a manual process known as Systematic Evolution of Ligands by Exponential Enrichment (SELEX), which is costly, slow, dependent on library choice and often produces aptamers that are not optimized. To address these challenges, in this research, we create an intelligent approach, named DAPTEV, for generating and evolving aptamer sequences to support aptamer-based drug discovery and development. Using the COVID-19 spike protein as a target, our computational results suggest that DAPTEV is able to produce structurally complex aptamers with strong binding affinities.


Asunto(s)
Aptámeros de Nucleótidos , COVID-19 , Humanos , Aptámeros de Nucleótidos/química , Técnica SELEX de Producción de Aptámeros/métodos , Diseño de Fármacos , ARN , Ligandos
10.
Artículo en Inglés | MEDLINE | ID: mdl-38408517

RESUMEN

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.


Asunto(s)
Bivalvos , Fosfotransferasas (Aceptor de Grupo Alcohol) , Tolerancia a la Sal , Animales , Bivalvos/metabolismo , Prolina/metabolismo , Glutamatos/metabolismo
11.
Plant Dis ; 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38197883

RESUMEN

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.

12.
Protein Expr Purif ; 210: 106316, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37271410

RESUMEN

WuXiBody is a bispecific antibody (bsAb) platform developed by WuXi Biologics. Its key feature is the replacement of one parental antibody's CH1/CL region with the T-cell receptor (TCR) constant domain, which prevents mispairing between non-cognate heavy chain and light chain. In addition, heavy chain heterodimerization in asymmetric WuXiBody molecule is promoted by the knobs-into-holes (KiH) technology. Despite the great success of KiH strategy in improving heterodimer formation, homodimers (especially the hole-hole homodimer) can still be generated at low levels. In general, detection and monitoring of homodimers during KiH bsAb purification are challenging as homodimers share similar physicochemical properties with the target heterodimeric bsAb. Nevertheless, the unique design of WuXiBody allows homodimers to be effectively detected and monitored by multiple methods. In the current work, with an asymmetric WuXiBody case study, we demonstrated that hole-hole homodimer can be effectively monitored by six chromatography methods including hydrophobic interaction chromatography (HIC), reverse phase (RP), cation exchange (CEX), KappaSelect, CaptureSelect CH1-XL and Protein L.


Asunto(s)
Anticuerpos Biespecíficos , Cromatografía , Dimerización , Anticuerpos Biespecíficos/química
13.
Protein Expr Purif ; 203: 106217, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36529448

RESUMEN

For recombinantly produced monoclonal antibody (mAb), charge variants including acidic and basic species are common heterogeneities. For characterization purpose, sufficient amount of acidic and basic species with high purity is needed. In this work, we developed an approach that allows for continuous separating and collecting of acidic and basic charge variants. First, with batch-mode cation exchange (CEX) chromatography, the load density and linear salt gradient elution conditions under which good separation of both charge variants can be achieved were determined. Next, a stepwise elution protocol was developed based on the linear gradient elution. Finally, acidic and basic charge variants were persistently produced under stepwise elution using a customized twin-column continuous chromatography system. This approach allows acidic and basic charge variants with high purity (i.e., >90%) to be efficiently generated in sufficient amount, which greatly facilitates the necessary characterization of these mAb variants.


Asunto(s)
Anticuerpos Monoclonales , Cloruro de Sodio , Cromatografía por Intercambio Iónico/métodos , Cloruro de Sodio/química , Anticuerpos Monoclonales/química , Cationes/química
14.
Protein Expr Purif ; 210: 106297, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37209930

RESUMEN

In downstream processing of protein therapeutics, ion exchange (IEX) chromatography is a powerful tool for removing byproducts whose isoelectric point (pI) is appreciably different from that of the product. Although in theory for a given case cation exchange (CEX) and anion exchange (AEX) chromatography should be equally effective for separation, in reality they may show different effectiveness. In the current work, with a case study, we demonstrated that AEX is more effective than CEX chromatography at removing the associated byproducts. In addition, we screened AEX resins and loading conditions to achieve best separation. Finally, we demonstrated that effective separation was achieved with the selected resin/condition, and chromatography performance was comparable between runs conducted at low and high load densities, suggesting that the developed process was relatively robust. The procedure described in this work can be used as a general approach for selecting resin and loading condition that allow for effective and robust removal of byproduct that binds weaker than the product to the selected type of column.


Asunto(s)
Resinas de Intercambio Aniónico , Cromatografía por Intercambio Iónico/métodos , Resinas de Intercambio Aniónico/química , Aniones , Cationes/química
15.
Protein Expr Purif ; 210: 106315, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37271409

RESUMEN

Protein A affinity chromatography has been widely used for antibody capture and initial purification. In general, the yield of this step is relatively high (i.e., >90%). However, recently while purifying a bispecific antibody (bsAb) in appended IgG format, the Protein A capture step experienced low yield (i.e., ∼80%). It was found that the target bsAb started appearing in flow-through at a relatively low load density, suggesting that a portion of the expressed bsAb has compromised Protein A binding capability. Further studies indicated that the bsAb in flow-through was mainly in aggregate form. In addition, normal Protein A step yield was restored when the column was loaded with bsAb monomer. Thus, all the evidence pointed to the fact that aggregate with compromised binding capacity was the cause of low Protein A step yield in this case.


Asunto(s)
Anticuerpos Biespecíficos , Proteína Estafilocócica A , Anticuerpos Biespecíficos/química
16.
Heredity (Edinb) ; 130(4): 259-268, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36788365

RESUMEN

The evolutionary transition from self-incompatible distyly to self-compatible homostyly frequently occurs in heterostylous taxa. Although the inheritance of distyly and homostyly has been deeply studied, our understanding on modifications of the classical simple Mendelian model is still lacking. Primula forbesii, a biennial herb native to southwest China, is a typical distylous species, but after about 20 years of cultivation with open pollination, self-compatible homostyly appeared, providing ideal material for the study of the inheritance of distyly and homostyly. In this study, exogenous homobrassinolide was used to break the heteromorphic incompatibility of P. forbesii. Furthermore, we performed artificial pollination and open-pollination experiments to observe the distribution of floral morphs in progeny produced by different crosses. The viability of seeds from self-pollination was always the lowest among all crosses, and the homozygous S-morph plants (S/S) occurred in artificial pollination experiments but may experience viability selection. The distyly of P. forbesii is governed by a single S-locus, with S-morph dominant hemizygotes (S/-) and L-morph recessive homozygotes (-/-). Homostylous plants have a genotype similar to L-morph plants, and homostyly may be caused by one or more unlinked modifier genes outside the S-locus. Open pollinations confirm that autonomous self-pollination occurs frequently in L-morphs and homostylous plants. This study deepens the understanding of the inheritance of distyly and details a case of homostyly that likely originated from one or more modifier genes.


Asunto(s)
Primula , Humanos , Primula/genética , Flores/genética , Polinización/genética , Patrón de Herencia , Evolución Biológica
17.
Bioorg Med Chem Lett ; 82: 129150, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36693483

RESUMEN

Using anion-exchange high performance liquid chromatography under non-denaturing conditions, the conformational flexibility of adenosine-, ampicillin-, and quinine aptamers were studied. It was found that all three aptamers showed more than one species when not subjected to thermal anneal. Addition of ligand to untreated aptamers did not significantly change the structural distribution. Upon heating followed by slow cooling, however, all three aptamers were found to exist virtually solely in one structure, presumably the partial hairpin species. It was also found that sonication of quinine aptamer, but not adenosine and ampicillin aptamer, led to its elution off HPLC as virtually a single species. These changes in conformational distribution as a result of thermal anneal or sonication were further confirmed by UV/vis and circular dichroism spectroscopy, as well as melt curves. The findings provided basis for future optimization of aptamer selection and preparation, where thermal anneal can help optimize selection efficiency and improve the consistency in the interpretation of results.


Asunto(s)
Aptámeros de Nucleótidos , Aptámeros de Nucleótidos/química , Quinina
18.
Mol Divers ; 27(5): 2239-2255, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36331785

RESUMEN

There has been considerable interest in transforming peptides into small molecules as peptide-based molecules often present poorer bioavailability and lower metabolic stability. Our studies looked into building machine learning (ML) models to investigate if ML is able to identify the 'bioactive' features of peptides and use the features to accurately discriminate between binding and non-binding small molecules. The ghrelin receptor (GR), a receptor that is implicated in various diseases, was used as an example to demonstrate whether ML models derived from a peptide library can be used to predict small molecule binders. ML models based on three different algorithms, namely random forest, support vector machine, and extreme gradient boosting, were built based on a carefully curated dataset of peptide/peptidomimetic and small molecule GR ligands. The results indicated that ML models trained with a dataset exclusively composed of peptides/peptidomimetics provide limited predictive power for small molecules, but that ML models trained with a diverse dataset composed of an array of both peptides/peptidomimetics and small molecules displayed exceptional results in terms of accuracy and false rates. The diversified models can accurately differentiate the binding small molecules from non-binding small molecules using an external validation set with new small molecules that we synthesized previously. Structural features that are the most critical contributors to binding activity were extracted and are remarkably consistent with the crystallography and mutagenesis studies.


Asunto(s)
Peptidomiméticos , Peptidomiméticos/química , Receptores de Ghrelina , Ligandos , Péptidos/química , Aprendizaje Automático , Máquina de Vectores de Soporte
19.
Graefes Arch Clin Exp Ophthalmol ; 261(10): 2987-2996, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37148291

RESUMEN

PURPOSE: To compare the diagnostic value of ultrasonic elastosonography (UE) and contrast-enhanced ultrasonography (CEUS) for benign and malignant intraocular tumors. METHODS: This retrospective study enrolled patients with intraocular tumors at Beijing Tongren Hospital, Capital Medical University (August 2016 to January 2020). The strain rate ratio (strain rate of tumor tissue divided by strain rate of surrounding normal tissue) was measured by UE. CEUS was performed using SonoVue® contrast agent. The performance of each method at differentiating benign from malignant intraocular tumors was evaluated by receiver operating characteristic curve analysis. RESULTS: The analysis included 147 eyes in 145 patients (45.6 ± 13.4 years-old; 66 males): 117 patients (119 eyes) with malignant tumors and 28 patients (28 eyes) with benign tumors. At an optimal cutoff of 22.67 for the strain rate ratio, UE distinguished benign from malignant tumors with a sensitivity of 86.6% and a specificity of 96.4%. CEUS showed that 117 eyes with malignant tumors had a fast-in, fast-out time-intensity curve, and only two eyes with malignant tumors had a fast-in, slow-out curve, while all 28 eyes with benign tumors had a fast-in, slow-out curve. CEUS differentiated benign from malignant tumors with a sensitivity of 98.3% and a specificity of 100%. The diagnostic results differed significantly between the two methods (P = 0.004, McNemar test). The diagnostic performances of the two tests were moderately consistent (κ = 0.657, P < 0.001). CONCLUSION: Both CEUS and UE have good diagnostic value in the differentiation of benign intraocular tumors from malignant intraocular tumors.


Asunto(s)
Neoplasias , Ultrasonido , Masculino , Humanos , Adulto , Persona de Mediana Edad , Estudios Retrospectivos , Medios de Contraste , Ultrasonografía/métodos , Sensibilidad y Especificidad , Diagnóstico Diferencial
20.
Postgrad Med J ; 99(1175): 1013-1019, 2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37209147

RESUMEN

BACKGROUND: The role and extent of the effects of short-term behavioral factors on the risk of hemorrhagic stroke (HS) are unclear. This study aimed to assess and quantify behavioral trigger factors (BTFs) for HS and identify the differences in BTFs between Chinese and other populations. METHODS: A case-crossover study was performed from March 2021 to February 2022. New-onset HS patients were recruited from two university hospitals in China. The patients were interviewed to evaluate their exposure to 20 potential BTFs during the predefined risk and control periods and to estimate the odds ratios (ORs) and 95% confidence intervals (CIs). A comprehensive literature review was conducted to synthesize the evidence. RESULTS: A total of 284 patients with HS were included (150 with intracerebral hemorrhage and 134 with subarachnoid hemorrhage). Multivariate regression analysis showed that straining for defecation (OR: 3.06; 95% CI: 1.01-8.40), weightlifting (OR: 4.82; 95% CI: 1.02-22.83), overeating (OR: 4.33; 95% CI: 1.24-15.21), heavy physical exertion (OR: 3.02; 95% CI: 1.18-7.78), and chess/cards/mahjong games (OR: 2.51; 95% CI: 1.05-6.01) were associated with an increased risk within 2 hours before HS onset, and critical life events (OR: 3.81; 95% CI: 1.06-13.74) were associated with an increased risk 7 days before the onset of HS. Exposure to anger (OR: 3.17; 95% CI: 1.73-5.81) and heavy physical exertion (OR: 2.12; 95% CI: 1.65, 2.74) showed an increased risk of HS events after the pooled analysis. CONCLUSIONS: Several behavioral activities and mood modifications are associated with the onset of HS. In addition to the common BTFs, Chinese patients have specific BTFs due to their habits and customs distinct from those of different populations in other regions. Key messages What is already known on this topic It is known that several behavioral trigger factors (BTFs) are associated with the onset of hemorrhagic stroke (HS), such as vigorous physical exercise and anger. Evidence for other potential trigger factors was of less robustness. Which BTFs contribute to HS among the Chinese population is poorly understood, since individuals in different countries and regions have their own habits of life and customs. What this study adds Our study identified that two special behaviors, chess/card/mahjong games and critical life events, were associated with the onset of HS in Chinese populations, besides heavy physical exertion, weightlifting, overeating, and straining for defecation, which were previously reported in other populations. Heavy physical exertion and anger could potentially increase the risk of HS based on a comprehensive aggregation and evidence synthesis. How this study might affect research, practice, or policy Patients in different populations or regions may possess specific BTFs owing to their distinct habits and customs. Avoidance of these behaviors and regulation of emotions to maintain a steady mentality would help minimize exposure and prevent the disease for high-risk populations in China.


Asunto(s)
Accidente Cerebrovascular Hemorrágico , Accidente Cerebrovascular , Hemorragia Subaracnoidea , Humanos , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/complicaciones , Estudios Cruzados , Accidente Cerebrovascular Hemorrágico/etiología , Accidente Cerebrovascular Hemorrágico/complicaciones , Hemorragia Cerebral/etiología , Hemorragia Cerebral/complicaciones , Hemorragia Subaracnoidea/complicaciones , Hemorragia Subaracnoidea/epidemiología , Factores de Riesgo
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