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1.
J Gen Virol ; 105(5)2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38767609

RESUMEN

Hepeviruses have been identified in a broad range of animal hosts, including mammals, birds, and fish. In this study, rodents (n=91) from seven different species and ten pikas (Ochotona curzoniae) were collected in Qinghai Province, China. Using transcriptomic sequencing and confirmatory molecular testing, hepeviruses were detected in 27 of 45 (60 %) long-tailed dwarf hamsters (Cricetulus longicaudatus) and were undetected in other rodents and pika. The complete genome sequences from 14 representative strains were subsequently obtained, and phylogenetic analyses suggested that they represent a novel species within the genus Rocahepevirus, which we tentatively designated as Cl-2018QH. The virus was successfully isolated in human hepatoma (Huh-7) and murine fibroblast (17 Cl-1) cell lines, though both exhibited limited replication as assayed by detection of negative-sense RNA intermediates. A129 immunodeficient mice were inoculated with Cl-2018QH and the virus was consistently detected in multiple organs, despite relatively low viral loads. In summary, this study has described a novel rodent hepevirus, which enhances our knowledge of the genetic diversity of rodent hepeviruses and highlights its potential for cross-species transmission.


Asunto(s)
Genoma Viral , Hepevirus , Filogenia , Animales , China , Cricetinae , Ratones , Hepevirus/genética , Hepevirus/aislamiento & purificación , Hepevirus/clasificación , Humanos , Línea Celular , ARN Viral/genética
2.
Virus Res ; 345: 199388, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38714218

RESUMEN

Human enteroviruses (EVs) represent a global public health concern due to their association with a range of serious pediatric illnesses. Despite the high morbidity and mortality exerted by EVs, no broad-spectrum antivirals are currently available. Herein, we presented evidence that doxycycline can inhibit in vitro replication of various neurotropic EVs, including enterovirus A71 (EV-A71), enterovirus D68 (EV-D68), and coxsackievirus (CV)-A6, in a dose-dependent manner. Further investigations indicated that the drug primarily acted at the post-entry stage of virus infection in vitro, with inhibitory effects reaching up to 89 % for EV-A71 when administered two hours post-infection. These findings provide valuable insights for the development of antiviral drugs against EV infections.

3.
J Transl Med ; 22(1): 283, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38491378

RESUMEN

The activation of glycolysis, particularly in the context of reprogrammed energy metabolism, is increasingly recognized as a significant characteristic of cancer. However, the precise mechanisms by which glycolysis is promoted in metastatic gastric cancer cells under normal oxygen conditions remain poorly understood. MicroRNAs (miRNAs) play a crucial role in the development of malignant phenotypes in gastric cancer. Nevertheless, our understanding of the specific involvement of miRNAs in hypoxia-induced metabolic shifting and the subsequent metastatic processes is limited. Hypoxia-induced downregulation of miR-598-3p mechanistically leads to the upregulation of RMP and IGF1r, thereby promoting glycolysis. Either overexpression of miR-598-3p or R406 treatment effectively suppresses the metastasis of gastric cancer cells both in vitro and in vivo. Collectively, the depletion of miR-598-3p alters glucose metabolism from oxidative phosphorylation to glycolysis, thereby exacerbating the malignancy of gastric cancer cells. The present findings indicate a potential target for the development of therapeutics against gastric cancers with increased miR-598-3p expression.


Asunto(s)
MicroARNs , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , MicroARNs/metabolismo , Hipoxia/genética , Glucólisis/genética , Proliferación Celular/genética , Línea Celular Tumoral
4.
Cancer Immunol Immunother ; 73(4): 65, 2024 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-38430390

RESUMEN

BACKGROUND: Group 2 innate lymphoid cells (ILC2s) represent one of the main tissue-specific innate lymphoid cell populations, which are key drivers of cytokine secretion in their occupational niche. However, the precise involvement of ILC2s in cancer immunity and their potential impact on immunotherapeutic approaches remain poorly understood. METHODS: The proportion of ILC2s originating from various tissue sources were quantified through flow cytometry, along with the determination of CD4+ T cell and CD8+ T cell percentages. Flow cytometry was also employed to assess IFN-γ production and programmed cell death protein-1 (PD-1) expression in T cells. Immunohistochemistry was utilized to detect IL-33 expression in tumor tissues, while immunofluorescence was employed to confirm the infiltration of ILC2s in both murine and human tumor tissues. RESULTS: In this study, we provide evidence that intra-tumoral ILC2s in lung adenocarcinoma (LUAD) exist in a quiescent state. However, the activation of intra-tumoral ILC2s is induced by IL-33 specifically in a natural ILC2s (nILC2, ST2+KLRG1-) phenotype. Considering the pivotal role of PD-1 in cancer immunotherapy and its immunoregulatory functions, we investigated the synergistic effects of IL-33 and anti-PD-1 and found that their combination enhances anti-tumor immunity and improves the efficacy of immunotherapy. Moreover, this combination leads to the upregulation of activated mature ILC2s (mILC2, ST2+KLRG1+) phenotype, thereby highlighting the activated ILC2s as a novel enhancer of the immunoregulatory properties of anti-PD-1. CONCLUSIONS: Collectively, these findings underscore the significance of ILC2s and their contribution to the anti-tumor response in the context of cancer immunotherapy. Consequently, the simultaneous targeting of ILC2s and T cells represents a potentially promising and widely applicable strategy for immunotherapeutic interventions.


Asunto(s)
Inmunidad Innata , Neoplasias , Humanos , Ratones , Animales , Linfocitos , Interleucina-33 , Receptor de Muerte Celular Programada 1 , Proteína 1 Similar al Receptor de Interleucina-1 , Neoplasias/terapia
5.
Zool Res ; 45(2): 429-438, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38485510

RESUMEN

The Chinese tree shrew ( Tupaia belangeri chinensis), a member of the mammalian order Scandentia, exhibits considerable similarities with primates, including humans, in aspects of its nervous, immune, and metabolic systems. These similarities have established the tree shrew as a promising experimental model for biomedical research on cancer, infectious diseases, metabolic disorders, and mental health conditions. Herein, we used meta-transcriptomic sequencing to analyze plasma, as well as oral and anal swab samples, from 105 healthy asymptomatic tree shrews to identify the presence of potential zoonotic viruses. In total, eight mammalian viruses with complete genomes were identified, belonging to six viral families, including Flaviviridae, Hepeviridae, Parvovirinae, Picornaviridae, Sedoreoviridae, and Spinareoviridae. Notably, the presence of rotavirus was recorded in tree shrews for the first time. Three viruses - hepacivirus 1, parvovirus, and picornavirus - exhibited low genetic similarity (<70%) with previously reported viruses at the whole-genome scale, indicating novelty. Conversely, three other viruses - hepacivirus 2, hepatovirus A and hepevirus - exhibited high similarity (>94%) to known viral strains. Phylogenetic analyses also revealed that the rotavirus and mammalian orthoreovirus identified in this study may be novel reassortants. These findings provide insights into the diverse viral spectrum present in captive Chinese tree shrews, highlighting the necessity for further research into their potential for cross-species transmission.


Asunto(s)
Tupaia , Virus , Animales , Filogenia , Primates , Musarañas , Tupaia/fisiología , Tupaiidae
6.
Heliyon ; 10(3): e24397, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38317924

RESUMEN

Lung adenocarcinoma (LUAD) is a highly lethal malignant tumor. While the involvement of multiple mRNAs in the progression of LUAD is well established, the potential diagnostic value of immune-related mRNAs (irmRNAs) in LUAD remains largely unexplored. In this study, we utilized RNA-seq, clinical data, and immune-related gene information from LUAD patients to identify differentially expressed immune-related mRNAs (DEirmRNAs) and developed a predictive risk model based on specific DEirmRNA pairs closely linked with patient prognosis. We classified patients into high-risk and low-risk groups and analyzed factors such as survival rate, clinical characteristics, gene enrichment, immune cell infiltration, tumor mutation load, and drug susceptibility. We confirmed the expression levels of these DEirmRNAs in tumor tissues using qRT-PCR assay. Our results showed that the low-risk group had a longer survival time and lower tumor mutation burden (TMB) and microsatellite instability (MSI) compared to the high-risk group. The high-risk group also had a significant reduction in the number of certain immune cells and a lower half-maximum inhibitor concentration (IC50). We identified specific DEirmRNA pairs that were up-regulated or down-regulated in tumor tissues compared to adjacent tissues. Our prognostic risk model based on DEirmRNA pairs could be used to predict the prognosis of LUAD patients and provide reference for better treatment.

7.
Sci China Life Sci ; 67(1): 188-203, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37922067

RESUMEN

Brine shrimp (Artemia) has existed on Earth for 400 million years and has major ecological importance in hypersaline ecosystems. As a crucial live food in aquaculture, brine shrimp cysts have become one of the most important aquatic products traded worldwide. However, our understanding of the biodiversity, prevalence and global connectedness of viruses in brine shrimp is still very limited. A total of 143 batches of brine shrimp (belonging to seven species) cysts were collected from six continents including 21 countries and more than 100 geographic locations worldwide during 1977-2019. In total, 55 novel RNA viruses were identified, which could be assigned to 18 different viral families and related clades. Eleven viruses were dsRNA viruses, 16 were +ssRNA viruses, and 28 were-ssRNA viruses. Phylogenetic analyses of the RNA-directed RNA polymerase (RdRp) showed that brine shrimp viruses were often grouped with viruses isolated from other invertebrates and fungi. Remarkably, most brine shrimp viruses were related to those from different hosts that might feed on brine shrimp or share the same ecological niche. A notable case was the novel brine shrimp noda-like virus 3, which shared 79.25% (RdRp) and 63.88% (capsid proteins) amino acid identity with covert mortality nodavirus (CMNV) that may cause losses in aquaculture. In addition, both virome composition and phylogenetic analyses revealed global connectedness in certain brine shrimp viruses, particularly among Asia and Northern America. This highlights the incredible species diversity of viruses in these ancient species and provides essential data for the prevalence of RNA viruses in the global aquaculture industry. More broadly, these findings provide novel insights into the previously unrecognized RNA virosphere in hypersaline ecosystems worldwide and demonstrate that human activity might have driven the global connectedness of brine shrimp viruses.


Asunto(s)
Quistes , Virus ARN , Animales , Humanos , Ecosistema , Artemia , Filogenia , Virus ARN/genética , ARN Polimerasa Dependiente del ARN
8.
Front Public Health ; 11: 1283158, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38026391

RESUMEN

Background: China discontinued the zero-COVID-19 policy on December 7, 2022, and then COVID-19 surged mid-December 2022 through mid-January 2023. However, the actual incidence was unknown. This study aimed to estimate the incidence of SARS-CoV-2 infection in children shortly after ending the zero-COVID-19 policy. Methods: This multicenter cross-sectional study included 1,065 children aged 8 months to 12 years from seven hospitals at six regions across Jiangsu province, based on the convenience sampling, from February 10 to March 10, 2023. Group I comprised 324 children aged 8 months-2 years without COVID-19 vaccination, group II consisted of 338 preschool children aged 3-5 years with varied vaccination history, and group III contained 403 primary school children aged 6-12 years with mostly vaccinated. The COVID-19 vaccines were composed of inactivated SARS-CoV-2. In addition, 96 children's sera collected in 2014 were included as negative controls. IgG and IgM antibodies against nucleocapsid (N) and subunit 1 of spike (S1) of SARS-CoV-2 (anti-N/S1) were measured with commercial kits (YHLO Biotech, Shenzhen, China). Results: None of the 96 children (5.1 ± 3.5 years; 58.3% boys) in 2014 was positive for anti-N/S1 IgG or IgM. Of the 1,065 children (5.0 ± 3.5 years; 56.0% boys), 988 (92.8%) were anti-N/S1 IgG positive but none was anti-N/S1 IgM positive. The positive rate of anti-N/S1 IgG in Group I, II, and III was 90.4, 88.5, and 98.3%, respectively, with significantly higher in group III than in groups I and II (p < 0.0001). The median antibody titers in group III (381.61 AU/ml) were much higher than that in group I (38.34 AU/ml) and II (51.88 AU/ml; p < 0.0001). Conclusion: More than 90% children experienced SARS-CoV-2 infection shortly after ending zero-COVID-19 policy in China, much higher than estimated infections by other studies. The widespread SARS-CoV-2 infection in unvaccinated children should be influential on the policy of COVID-19 vaccination in children in the future.


Asunto(s)
COVID-19 , Masculino , Preescolar , Humanos , Niño , Femenino , COVID-19/epidemiología , COVID-19/prevención & control , Estudios Transversales , Vacunas contra la COVID-19 , Incidencia , SARS-CoV-2 , China/epidemiología , Estudios Seroepidemiológicos , Inmunoglobulina M , Políticas , Inmunoglobulina G
9.
Zool Res ; 44(6): 1015-1025, 2023 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-37804113

RESUMEN

Following the outbreak of coronavirus disease 2019 (COVID-19), several severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-related coronaviruses have been discovered. Previous research has identified a novel lineage of SARS-CoV-2-related CoVs in bats, including RsYN04, which recognizes human angiotensin-converting enzyme 2 (ACE2) and thus poses a potential threat to humans. Here, we screened the binding of the RsYN04 receptor-binding domain (RBD) to ACE2 orthologs from 52 animal species and found that the virus showed a narrower ACE2-binding spectrum than SARS-CoV-2. However, the presence of the T484W mutation in the RsYN04 RBD broadened its range. We also evaluated 44 SARS-CoV-2 antibodies targeting seven epitope communities in the SARS-CoV-2 RBD, together with serum obtained from COVID-19 convalescents and vaccinees, to determine their cross-reaction against RsYN04. Results showed that no antibodies, except for the RBD-6 and RBD-7 classes, bound to the RsYN04 RBD, indicating substantial immune differences from SARS-CoV-2. Furthermore, the structure of the RsYN04 RBD in complex with cross-reactive antibody S43 in RBD-7 revealed a potently broad epitope for the development of therapeutics and vaccines. Our findings suggest RsYN04 and other viruses belonging to the same clade have the potential to infect several species, including humans, highlighting the necessity for viral surveillance and development of broad anti-coronavirus countermeasures.


Asunto(s)
COVID-19 , Quirópteros , Animales , Humanos , SARS-CoV-2 , COVID-19/veterinaria , Enzima Convertidora de Angiotensina 2 , Quirópteros/genética , Anticuerpos Antivirales , Epítopos
10.
J Cell Biol ; 222(12)2023 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-37906052

RESUMEN

Enterovirus 71 (EV71) and Coxsackie A16 (CVA16) are two major causative agents of hand, foot, and mouth disease (HFMD) in young children. However, the mechanisms regulating the replication and pathogenesis of EV71/CVA16 remain incompletely understood. We performed a genome-wide CRISPR-Cas9 knockout screen and identified Ragulator as a mediator of EV71-induced apoptosis and pyroptosis. The Ragulator-Rag complex is required for EV71 and CVA16 replication. Upon infection, the Ragulator-Rag complex recruits viral 3D protein to the lysosomal surface through the interaction between 3D and RagB. Disruption of the lysosome-tethered Ragulator-Rag-3D complex significantly impairs the replication of EV71/CVA16. We discovered a novel EV71 inhibitor, ZHSI-1, which interacts with 3D and significantly reduces the lysosomal tethering of 3D. ZHSI-1 treatment significantly represses replication of EV71/CVA16 as well as virus-induced pyroptosis associated with viral pathogenesis. Importantly, ZHSI-1 treatment effectively protects against EV71 infection in neonatal and young mice. Thus, our study indicates that targeting lysosome-tethered Ragulator-Rag-3D may be an effective therapeutic strategy for HFMD.


Asunto(s)
Enterovirus Humano A , Enfermedad de Boca, Mano y Pie , Proteínas no Estructurales Virales , Animales , Ratones , Apoptosis , Sistemas CRISPR-Cas , Enterovirus Humano A/genética , Lisosomas , Piroptosis , Proteínas no Estructurales Virales/genética , Replicación Viral , Enfermedad de Boca, Mano y Pie/virología , Modelos Animales de Enfermedad
11.
J Virol ; 97(10): e0078623, 2023 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-37796126

RESUMEN

IMPORTANCE: EV71 poses a significant health threat to children aged 5 and below. The process of EV71 infection and replication is predominantly influenced by ubiquitination modifications. Our previous findings indicate that EV71 prompts the activation of host deubiquitinating enzymes, thereby impeding the host interferon signaling pathway as a means of evading the immune response. Nevertheless, the precise mechanisms by which the host employs ubiquitination modifications to hinder EV71 infection remain unclear. The present study demonstrated that the nonstructural protein 2Apro, which is encoded by EV71, exhibits ubiquitination and degradation mediated by the host E3 ubiquitin ligase SPOP. In addition, it is the first report, to our knowledge, that SPOP is involved in the host antiviral response.


Asunto(s)
Cisteína Endopeptidasas , Enterovirus Humano A , Infecciones por Enterovirus , Interacciones Microbiota-Huesped , Ubiquitina-Proteína Ligasas , Ubiquitina , Ubiquitinación , Proteínas Virales , Niño , Humanos , Enterovirus Humano A/enzimología , Enterovirus Humano A/fisiología , Infecciones por Enterovirus/metabolismo , Infecciones por Enterovirus/virología , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas Virales/antagonistas & inhibidores , Proteínas Virales/metabolismo , Cisteína Endopeptidasas/metabolismo
12.
Front Microbiol ; 14: 1255716, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37744931

RESUMEN

It is vital to diagnose pathogens quickly and effectively in the research and treatment of disease. Argonaute (Ago) proteins are recently discovered nucleases with nucleic acid shearing activity that exhibit specific recognition properties beyond CRISPR-Cas nucleases, which are highly researched but restricted PAM sequence recognition. Therefore, research on Ago protein-mediated nucleic acid detection technology has attracted significant attention from researchers in recent years. Using Ago proteins in developing nucleic acid detection platforms can enable efficient, convenient, and rapid nucleic acid detection and pathogen diagnosis, which is of great importance for human life and health and technological development. In this article, we introduce the structure and function of Argonaute proteins and discuss the latest advances in their use in nucleic acid detection.

13.
PLoS One ; 18(9): e0290905, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37729271

RESUMEN

BACKGROUND: The purpose of this study was to investigate the role of preoperative lymphocytes, albumin, neutrophils, and LANR in the prognosis of patients with stage IB-IIA cervical cancer (CC). METHODS: We made a retrospective analysis of the clinical information and related materials of 202 patients with stage IB-IIA primary cervical cancer who had undergone a radical hysterectomy in the Department of Gynecology at the Affiliated Hospital of Jiangnan University between January 2017 and December 2018. The definition of LANR was as follows: LANR, lymphocyte × albumin / neutrophil. The receiver operating characteristic curve (ROC) was generated to determine the best cut-off values for these parameters, as well as the sensitivity and specificity of LANR in predicting recurrence and survival. The Kaplan-Meier method was employed to draw survival curves in our survival analysis. Univariate analysis, multifactorial analysis, and subgroup analysis were used to evaluate the prognostic significance of LANR in overall and progression-free survival. RESULTS: The median follow-up time of the study was 55 months. In overall survival, the area under the curve for LANR was 0.704 (95% CI: 0.590-0.818, p<0.05). And in progression-free survival, the area under the curve for LANR was 0.745 (95% CI: 0.662-0.828, p<0.05). Univariate and multivariate analyses showed that the value of LANR was associated with both overall survival and progression-free survival (p< 0.05). Kaplan-Meier analysis demonstrated that OS (p< 0.001) and PFS (p< 0.001) in patients with high LANR levels were significantly higher than those with low LANR levels. CONCLUSIONS: Our findings suggested that LANR might serve as a clinically reliable and effective independent prognostic indicator in patients with stage IB-IIA cervical cancer.


Asunto(s)
Neoplasias del Cuello Uterino , Femenino , Humanos , Neoplasias del Cuello Uterino/cirugía , Neutrófilos , Pronóstico , Estudios Retrospectivos , Albúminas , Linfocitos
14.
Virology ; 587: 109855, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37536021

RESUMEN

Influenza C virus (ICV) was identified in five pediatric acute respiratory cases in Shandong. Co-infection with other respiratory viruses was detected in four of these cases. Two ICV genomes were obtained and clustered in the S1-sublineage of C/Sao Paulo/378/82, indicating that genetically diverse ICV strains have been circulating in mainland China.

15.
ACS Nano ; 17(16): 15466-15473, 2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37573571

RESUMEN

The nanobridge junction (NBJ) is a type of Josephson junction that is advantageous for the miniaturization of superconducting circuits. However, the current-phase relation (CPR) of the NBJ usually deviates from a sinusoidal function, which has been explained by a simplified model with correlation only to its effective length. Here, we investigated both measured and calculated CPRs of niobium NBJs of a cuboidal shape with a three-dimensional bank structure. From a sine-wave to a sawtooth-like form, we showed that deviated CPRs of NBJs can be described quantitatively by its skewness Δθ. Furthermore, the measured dependence of Δθ on the critical current I0 from 108 NBJs turned out to be consistent with the calculated dependence derived from the change in geometric dimensions. This suggested that the CPRs of NBJs can be tuned by their geometric dimensions. In addition, the calculated scaling behavior of Δθ versus I0 in 3D space was provided for the future design of superconducting circuits of a high integration level by using niobium NBJs.

16.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 39(8): 729-736, 2023 Aug.
Artículo en Chino | MEDLINE | ID: mdl-37515340

RESUMEN

Objectives Objectives To investigate how the imbalance of innate lymphoid cells (ILCs)in the peripheral blood of patients with lung adenocarcinoma affects the balance of downstream mononuclear macrophages and T helper (Th) cells, and to identify the impact of the imbalance of ILCs on the immune status and prognosis of lung adenocarcinoma. Methods The peripheral blood of 20 patients with lung adenocarcinoma and normal controls were collected. The percentage of ILCs, mononuclear macrophages and T lymphocyte in peripheral blood were analyzed by flow cytometry. The characteristic cytokine secretion levels of various types of immune cells in peripheral blood were detected by real-time fluorescence quantitative PCR. Results Compared with the normal controls, the proportion of M2 mononuclear macrophages, ILC1 and ILC2 in patients with lung adenocarcinoma was up-regulated, while the proportion of M1 mononuclear macrophages, CD4+ T and CD8+ T was down-regulated. The mRNA expression of related cytokines of M1 mononuclear macrophages and ILC1 were decreased; while the mRNA expression of related cytokines of M2 mononuclear macrophages and ILC2 were increased. Along with the decreased CD4+T cells-associated cytokine T-bet mRNA expression, and the increased GATA3 mRNA expression. Moreover, the expression of PD-1 in CD8+ T cells was also up-regulated. Conclusion The imbalance of ILCs in peripheral blood of patients with lung adenocarcinoma promotes the imbalance of mononuclear macrophages and Th cells, which altogether maintains the immunosuppression in patients with lung adenocarcinoma, and promotes the development of lung adenocarcinoma.


Asunto(s)
Adenocarcinoma del Pulmón , Linfocitos , Humanos , Inmunidad Innata , Linfocitos T CD8-positivos , Citocinas/metabolismo , Terapia de Inmunosupresión , ARN Mensajero
18.
RSC Adv ; 13(27): 18953-18959, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37350861

RESUMEN

Chiral motifs of 2,3-dihydro-1,4 benzodioxane are extensively utilized in diverse medicinal substances and bioactive natural compounds, exhibiting significant biological activities. Notable examples of such therapeutic agents include prosympal, dibozane, piperoxan, and doxazosin. In this work, using 1,4-benzodioxane-2-carboxylic acid methyl ester as the substrate, after screening 38 CALB covariant residues, we found that mutants A225F and A225F/T103A can catalyze the kinetic resolution of the substrate. The effect of temperature, cosolvent, and cosolvent concentration on kinetic resolution was investigated, revealing that the best results were achieved at 30 °C with 20% n-butanol as a cosolvent, resulting in an optimal resolution (e.e.s 97%, E = 278) at 50 mM substrate concentration. Structure analysis showed that mutation sites 225 and 103 are not among the sites that interact directly with the substrate, which means that covariant amino acids that interact remotely with the substrate also regulate enzyme catalysis. This research may provide us with a new strategy for enzyme evolution.

19.
iScience ; 26(6): 106799, 2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37250798

RESUMEN

The impairment of antibody-mediated immunity is a major factor associated with fatal cases of severe fever with thrombocytopenia syndrome (SFTS). By collating the clinical diagnosis reports of 30 SFTS cases, we discovered the overproliferation of monoclonal plasma cells (MCP cells, CD38+cLambda+cKappa-) in bone marrow, which has only been reported previously in multiple myeloma. The ratio of CD38+cLambda+ versus CD38+cKappa+ in SFTS cases with MCP cells was significantly higher than that in normal cases. MCP cells presented transient expression in the bone marrow, which was distinctly different from multiple myeloma. Moreover, the SFTS patients with MCP cells had higher clinical severity. Further, the overproliferation of MCP cells was also observed in SFTS virus (SFTSV)-infected mice with lethal infectious doses. Together, SFTSV infection induces transient overproliferation of monoclonal lambda-type plasma cells, which have important implications for the study of SFTSV pathogenesis, prognosis, and the rational development of therapeutics.

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