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1.
Cell ; 181(4): 894-904.e9, 2020 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-32275855

RESUMEN

The recent emergence of a novel coronavirus (SARS-CoV-2) in China has caused significant public health concerns. Recently, ACE2 was reported as an entry receptor for SARS-CoV-2. In this study, we present the crystal structure of the C-terminal domain of SARS-CoV-2 (SARS-CoV-2-CTD) spike (S) protein in complex with human ACE2 (hACE2), which reveals a hACE2-binding mode similar overall to that observed for SARS-CoV. However, atomic details at the binding interface demonstrate that key residue substitutions in SARS-CoV-2-CTD slightly strengthen the interaction and lead to higher affinity for receptor binding than SARS-RBD. Additionally, a panel of murine monoclonal antibodies (mAbs) and polyclonal antibodies (pAbs) against SARS-CoV-S1/receptor-binding domain (RBD) were unable to interact with the SARS-CoV-2 S protein, indicating notable differences in antigenicity between SARS-CoV and SARS-CoV-2. These findings shed light on the viral pathogenesis and provide important structural information regarding development of therapeutic countermeasures against the emerging virus.


Asunto(s)
Betacoronavirus/química , Peptidil-Dipeptidasa A/química , Glicoproteína de la Espiga del Coronavirus/química , Internalización del Virus , Secuencia de Aminoácidos , Enzima Convertidora de Angiotensina 2 , Betacoronavirus/fisiología , Epítopos , Humanos , Modelos Moleculares , Peptidil-Dipeptidasa A/metabolismo , Filogenia , Dominios Proteicos , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/química , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/fisiología , SARS-CoV-2 , Alineación de Secuencia , Glicoproteína de la Espiga del Coronavirus/metabolismo
2.
Chem Rev ; 124(13): 8550-8595, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38885177

RESUMEN

Biomolecular condensates, formed through phase separation, are upending our understanding in much of molecular, cell, and developmental biology. There is an urgent need to elucidate the physicochemical foundations of the behaviors and properties of biomolecular condensates. Here we aim to fill this need by writing a comprehensive, critical, and accessible review on the fundamental aspects of phase-separated biomolecular condensates. We introduce the relevant theoretical background, present the theoretical basis for the computation and experimental measurement of condensate properties, and give mechanistic interpretations of condensate behaviors and properties in terms of interactions at the molecular and residue levels.


Asunto(s)
Condensados Biomoleculares , Condensados Biomoleculares/química , Condensados Biomoleculares/metabolismo , Proteínas/química , Proteínas/metabolismo , Humanos , Transición de Fase
3.
Nature ; 581(7807): 215-220, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32225176

RESUMEN

A new and highly pathogenic coronavirus (severe acute respiratory syndrome coronavirus-2, SARS-CoV-2) caused an outbreak in Wuhan city, Hubei province, China, starting from December 2019 that quickly spread nationwide and to other countries around the world1-3. Here, to better understand the initial step of infection at an atomic level, we determined the crystal structure of the receptor-binding domain (RBD) of the spike protein of SARS-CoV-2 bound to the cell receptor ACE2. The overall ACE2-binding mode of the SARS-CoV-2 RBD is nearly identical to that of the SARS-CoV RBD, which also uses ACE2 as the cell receptor4. Structural analysis identified residues in the SARS-CoV-2 RBD that are essential for ACE2 binding, the majority of which either are highly conserved or share similar side chain properties with those in the SARS-CoV RBD. Such similarity in structure and sequence strongly indicate convergent evolution between the SARS-CoV-2 and SARS-CoV RBDs for improved binding to ACE2, although SARS-CoV-2 does not cluster within SARS and SARS-related coronaviruses1-3,5. The epitopes of two SARS-CoV antibodies that target the RBD are also analysed for binding to the SARS-CoV-2 RBD, providing insights into the future identification of cross-reactive antibodies.


Asunto(s)
Betacoronavirus/química , Peptidil-Dipeptidasa A/química , Peptidil-Dipeptidasa A/metabolismo , Receptores Virales/química , Receptores Virales/metabolismo , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/metabolismo , Secuencia de Aminoácidos , Enzima Convertidora de Angiotensina 2 , Anticuerpos Neutralizantes/inmunología , Betacoronavirus/metabolismo , Sitios de Unión , Secuencia Conservada , Cristalografía por Rayos X , Epítopos/química , Epítopos/inmunología , Evolución Molecular , Humanos , Enlace de Hidrógeno , Modelos Moleculares , Unión Proteica , Dominios Proteicos , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/química , SARS-CoV-2 , Sales (Química)/química , Alineación de Secuencia , Agua/análisis , Agua/química
4.
Mol Cell Proteomics ; 23(6): 100770, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38641226

RESUMEN

Inhalation of crystalline silica dust induces incurable lung damage, silicosis, and pulmonary fibrosis. However, the mechanisms of the lung injury remain poorly understood, with limited therapeutic options aside from lung transplantation. Posttranslational modifications can regulate the function of proteins and play an important role in studying disease mechanisms. To investigate changes in posttranslational modifications of proteins in silicosis, combined quantitative proteome, acetylome, and succinylome analyses were performed with lung tissues from silica-injured and healthy mice using liquid chromatography-mass spectrometry. Combined analysis was applied to the three omics datasets to construct a protein landscape. The acetylation and succinylation of the key transcription factor STAT1 were found to play important roles in the silica-induced pathophysiological changes. Modulating the acetylation level of STAT1 with geranylgeranylacetone effectively inhibited the progression of silicosis. This report revealed a comprehensive landscape of posttranslational modifications in silica-injured mouse and presented a novel therapeutic strategy targeting the posttranslational level for silica-induced lung diseases.


Asunto(s)
Lisina , Procesamiento Proteico-Postraduccional , Proteoma , Factor de Transcripción STAT1 , Silicosis , Animales , Silicosis/metabolismo , Silicosis/tratamiento farmacológico , Silicosis/patología , Factor de Transcripción STAT1/metabolismo , Proteoma/metabolismo , Lisina/metabolismo , Acetilación/efectos de los fármacos , Ratones , Dióxido de Silicio , Pulmón/metabolismo , Pulmón/efectos de los fármacos , Pulmón/patología , Ratones Endogámicos C57BL , Proteómica/métodos , Masculino , Ácido Succínico/metabolismo
5.
J Biol Chem ; 300(6): 107379, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38762184

RESUMEN

Bacterial RecJ exhibits 5'→3' exonuclease activity that is specific to ssDNA; however, archaeal RecJs show 5' or 3' exonuclease activity. The hyperthermophilic archaea Methanocaldococcus jannaschii encodes the 5'-exonuclease MjRecJ1 and the 3'-exonuclease MjRecJ2. In addition to nuclease activity, archaeal RecJ interacts with GINS, a structural subcomplex of the replicative DNA helicase complex. However, MjRecJ1 and MjRecJ2 do not interact with MjGINS. Here, we report the structural basis for the inability of the MjRecJ2 homologous dimer to interact with MjGINS and its efficient 3' hydrolysis polarity for short dinucleotides. Based on the crystal structure of MjRecJ2, we propose that the interaction surface of the MjRecJ2 dimer overlaps the potential interaction surface for MjGINS and blocks the formation of the MjRecJ2-GINS complex. Exposing the interaction surface of the MjRecJ2 dimer restores its interaction with MjGINS. The cocrystal structures of MjRecJ2 with substrate dideoxynucleotides or product dCMP/CMP show that MjRecJ2 has a short substrate binding patch, which is perpendicular to the longer patch of bacterial RecJ. Our results provide new insights into the function and diversification of archaeal RecJ/Cdc45 proteins.


Asunto(s)
Proteínas Arqueales , Proteínas Arqueales/química , Proteínas Arqueales/metabolismo , Proteínas Arqueales/genética , Cristalografía por Rayos X , Methanocaldococcus/enzimología , Methanocaldococcus/metabolismo , Unión Proteica , Multimerización de Proteína , ADN Helicasas/metabolismo , ADN Helicasas/química , ADN Helicasas/genética , Modelos Moleculares , Exodesoxirribonucleasas/metabolismo , Exodesoxirribonucleasas/química , Exodesoxirribonucleasas/genética
6.
Nucleic Acids Res ; 51(14): 7649-7665, 2023 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-37334830

RESUMEN

Nucleic acid ADP-ribosylation has been established as a novel modification found in a wide diversity of prokaryotic and eukaryotic organisms. tRNA 2'-phosphotransferase 1 (TRPT1/TPT1/KptA) possesses ADP-ribosyltransferase (ART) activity and is able to ADP-ribosylate nucleic acids. However, the underlying molecular mechanism remains elusive. Here, we determined crystal structures of TRPT1s in complex with NAD+ from Homo sapiens, Mus musculus and Saccharomyces cerevisiae. Our results revealed that the eukaryotic TRPT1s adopt common mechanisms for both NAD+ and nucleic acid substrate binding. The conserved SGR motif induces a significant conformational change in the donor loop upon NAD+ binding to facilitate the catalytic reaction of ART. Moreover, the nucleic acid-binding residue redundancy provides structural flexibility to accommodate different nucleic acid substrates. Mutational assays revealed that TRPT1s employ different catalytic and nucleic acid-binding residues to perform nucleic acid ADP-ribosylation and RNA 2'-phosphotransferase activities. Finally, cellular assays revealed that the mammalian TRPT1 is able to promote endocervical HeLa cell survival and proliferation. Together, our results provide structural and biochemical insights into the molecular mechanism of TRPT1 for nucleic acid ADP-ribosylation.


Asunto(s)
Fosfotransferasas (Aceptor de Grupo Alcohol) , Proteínas de Saccharomyces cerevisiae , Animales , Humanos , Ratones , Adenosina Difosfato Ribosa/metabolismo , ADP Ribosa Transferasas/genética , ADP Ribosa Transferasas/metabolismo , ADP-Ribosilación , Células HeLa , NAD/metabolismo , Ácidos Nucleicos/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol)/química , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
7.
Stroke ; 55(6): 1592-1600, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38787930

RESUMEN

BACKGROUND: Current evidence provides limited support for the superiority of endovascular thrombectomy (EVT) in patients with M2 segment middle cerebral artery occlusion. We aim to investigate whether imaging features of M2 segment occlusion impact the effectiveness of EVT. METHODS: We conducted a retrospective cohort study from January 2017 to January 2022, drawing data from the CASE II registry (Computer-Based Online Database of Acute Stroke Patients for Stroke Management Quality Evaluation), which specifically documented patients with acute ischemic stroke presenting with M2 segment occlusion undergoing reperfusion therapy. Patients were stratified into the intravenous thrombolysis (IVT) group (IVT alone) and EVT group (IVT plus EVT or EVT alone). The primary outcome was a modified Rankin Scale score 0 to 2 at 90 days. Secondary outcomes included additional thresholds and distribution of modified Rankin Scale scores, 24-hour recanalization, early neurological deterioration, and relevant complications during hospitalization. Safety outcomes encompassed intracranial hemorrhagic events at 24 hours and mortality at 90 days. Binary logistic regression analyses with propensity score matching were used. Subgroup analyses were performed based on the anatomic site of occlusion, including right versus left, proximal versus distal, dominant/co-dominant versus nondominant, single versus double/triple branch(es), and anterior versus central/posterior branch. RESULTS: Among 734 patients (43.3% were females; median age, 73 years) with M2 segment occlusion, 342 (46.6%) were in the EVT group. Propensity score matching analysis revealed no statistical difference in the primary outcome (odds ratio, 0.860 [95% CI, 0.611-1.209]; P=0.385) between the EVT group and IVT group. However, EVT was associated with a higher incidence of subarachnoid hemorrhage (odds ratio, 6.655 [95% CI, 1.487-29.788]; P=0.004) and pneumonia (odds ratio, 2.015 [95% CI, 1.364-2.977]; P<0.001). Subgroup analyses indicated that patients in the IVT group achieved better outcomes when presenting with right, distal, or nondominant branch occlusion (Pall interaction<0.05). CONCLUSIONS: Our study showed similar efficiency of EVT versus IVT alone in acute M2 segment middle cerebral artery occlusion. This suggested that only specific patient subpopulations might have a potentially higher benefit of EVT over IVT alone. REGISTRATION: URL: https://clinicaltrials.gov; Unique identifier: NCT04487340.


Asunto(s)
Infarto de la Arteria Cerebral Media , Trombectomía , Terapia Trombolítica , Humanos , Masculino , Femenino , Trombectomía/métodos , Anciano , Infarto de la Arteria Cerebral Media/cirugía , Terapia Trombolítica/métodos , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Anciano de 80 o más Años , Procedimientos Endovasculares/métodos , Sistema de Registros , Accidente Cerebrovascular Isquémico/cirugía , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/terapia
8.
J Am Chem Soc ; 146(2): 1326-1336, 2024 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-38174879

RESUMEN

Adenosine triphosphate (ATP) is an abundant molecule with crucial cellular roles as the energy currency and a building block of nucleic acids and for protein phosphorylation. Here we show that ATP mediates the phase separation of basic intrinsically disordered proteins (bIDPs). In the resulting condensates, ATP is highly concentrated (apparent partition coefficients up to 7700) and serves as bridges between bIDP chains. These liquid-like droplets have some of the lowest interfacial tension (∼25 pN/µm) but high zero-shear viscosities (1-15 Pa s) due to the bridged protein networks, and yet their fusion has some of the highest speeds (∼1 µm/ms). The rapid fusion manifests extreme shear thinning, where the apparent viscosity is lower than zero-shear viscosity by over 100-fold, made possible by fast reformation of the ATP bridges. At still higher concentrations, ATP does not dissolve bIDP droplets but results in aggregates and fibrils.


Asunto(s)
Adenosina Trifosfato , Proteínas Intrínsecamente Desordenadas , Adenosina Trifosfato/metabolismo , Separación de Fases
9.
J Am Chem Soc ; 146(5): 3383-3395, 2024 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-38262618

RESUMEN

Phase separation has emerged as an important mechanism explaining the formation of certain biomolecular condensates. Biological phase separation is often driven by the multivalent interactions of modular protein domains. Beyond valency, the physical features of folded domains that promote phase separation are poorly understood. We used a model system─the small ubiquitin modifier (SUMO) and its peptide ligand, the SUMO interaction motif (SIM)─to examine how domain surface charge influences multivalency-driven phase separation. Phase separation of polySUMO and polySIM was altered by pH via a change in the protonation state of SUMO surface histidines. These effects were recapitulated by histidine mutations, which modulated SUMO solubility and polySUMO-polySIM phase separation in parallel and were quantitatively explained by atomistic modeling of weak interactions among proteins in the system. Thus, surface charge can tune the phase separation of multivalent proteins, suggesting a means of controlling phase separation biologically, evolutionarily, and therapeutically.


Asunto(s)
Separación de Fases , Proteínas
10.
J Synchrotron Radiat ; 31(Pt 2): 378-384, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38241124

RESUMEN

An integrated computer software system for macromolecular crystallography (MX) data collection at the BL02U1 and BL10U2 beamlines of the Shanghai Synchrotron Radiation Facility is described. The system, Finback, implements a set of features designed for the automated MX beamlines, and is marked with a user-friendly web-based graphical user interface (GUI) for interactive data collection. The Finback client GUI can run on modern browsers and has been developed using several modern web technologies including WebSocket, WebGL, WebWorker and WebAssembly. Finback supports multiple concurrent sessions, so on-site and remote users can access the beamline simultaneously. Finback also cooperates with the deployed experimental data and information management system, the relevant experimental parameters and results are automatically deposited to a database.

11.
BMC Cancer ; 24(1): 444, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600507

RESUMEN

BACKGROUND: Transforming growth factor-ß (TGF-ß) is a cytokine with multiple functions, including cell growth regulation, extracellular matrix production, angiogenesis homeostasis adjustment and et al. TGF-ß pathway activation promotes tumor metastasis/progression and mediates epithelial-mesenchymal transmission suppressing immunosurveillance in advanced tumors. GFH018, a small molecule inhibitor blocking TGF-ß signal transduction, inhibits the progression and/or metastasis of advanced cancers. This first-in-human study evaluated the safety, tolerability, pharmacokinetics (PK), and efficacy of GFH018 monotherapy in patients with advanced solid tumors. METHODS: This phase I, open-label, multicenter study used a modified 3+3 dose escalation and expansion design. Adult patients with advanced solid tumors failing the standard of care were enrolled. Starting at 5 mg, eight dose levels up to 85 mg were evaluated. Patients received GFH018 BID (14d-on/14d-off) starting on the 4th day after a single dose on cycle 1, day 1. Subsequent cycles were defined as 28 days. The study also explored the safety of 85 mg BID 7d-on/7d-off. Adverse events were graded using NCI criteria for adverse events (NCI-CTCAE v5.0). PK was analyzed using a noncompartmental method. Efficacy was evaluated using RECIST 1.1. Blood samples were collected for biomarker analysis. RESULTS: Fifty patients were enrolled and received at least one dose of GFH018. No dose-limiting toxicity occurred, and the maximum tolerated dose was not reached. Forty-three patients (86.0%) had at least one treatment-related adverse event (TRAE), and three patients (6.0%) had ≥ G3 TRAEs. The most common TRAEs (any grade/grade ≥3) were AST increased (18%/0%), proteinuria (14%/2%), anemia (14%/2%), and ALT increased (12%/0%). No significant cardiotoxicity or bleeding was observed. GFH018 PK was linear and dose-independent, with a mean half-life of 2.25-8.60 h from 5 - 85 mg. Nine patients (18.0%) achieved stable disease, and one patient with thymic carcinoma achieved tumor shrinkage, with the maximum target lesion decreased by 18.4%. Serum TGF-ß1 levels were not associated with clinical responses. The comprehensive recommended dose for Phase II was defined as 85 mg BID 14d-on/14d-off. CONCLUSIONS: GFH018 monotherapy presented a favorable safety profile without cardiac toxicity or bleeding. Modest efficacy warrants further studies, including combination strategies. TRIAL REGISTRATION: ClinicalTrial. gov ( https://www. CLINICALTRIALS: gov/ ), NCT05051241. Registered on 2021-09-02.


Asunto(s)
Neoplasias , Receptores de Factores de Crecimiento Transformadores beta , Adulto , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Criterios de Evaluación de Respuesta en Tumores Sólidos , Factor de Crecimiento Transformador beta , Receptores de Factores de Crecimiento Transformadores beta/antagonistas & inhibidores
12.
Eur J Pediatr ; 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38990386

RESUMEN

OBJECTIVE: The objective of this study was to investigate the association between total bilirubin and acute kidney injury (AKI) in neonates admitted to neonatal intensive care units (NICU). METHODS: All data utilized were extracted from Medical Information Mart for Intensive Care-III (MIMIC-III) in this retrospective cohort study. The primary outcome was the occurrence of AKI during hospitalization in the NICU, and the exposure was the initial measurement of total bilirubin levels within 24 h of neonatal admission to the NICU. The relationship between serum total bilirubin and AKI was evaluated by employing univariate and multivariate logistic regression models. Additionally, subgroup analyses were conducted based on birth weight, sepsis, and mechanical ventilation. RESULTS: This retrospective cohort study included a population of 1,726 neonates, and 95 neonates developed AKI. Total bilirubin, as a continuous variable, was linked with decreased AKI risk among neonates admitted to the NICU [odds ratio (OR) = 0.77, 95% confidence interval (CI): 0.64-0.92]. Similarly, when total bilirubin levels were categorized by tertiles, tertiles 3 showed a significant association with decreased AKI risk (OR = 0.39, 95%CI: 0.19-0.83). The relationship of total bilirubin level and AKI was also existent among neonates admitted to the NICU who were underweight, had not sepsis, and received mechanical ventilation. CONCLUSION: Total bilirubin level may be a protective factor for the risk of developing AKI.

13.
Plant Cell Rep ; 43(3): 65, 2024 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-38341396

RESUMEN

Microplastic pollution has emerged as a critical global environmental issue due to its widespread distribution, persistence, and potential adverse effects on ecosystems and human health. Although research on microplastic pollution in aquatic environments has gained significant attention. However, a limited literature has summarized the impacts of microplastic pollution the agricultural land and human health. Therefore, In the current review, we have discussed how microplastic(s) affect the microorganisms by ingesting the microplastic present in the soil, alternatively affecting the belowground biotic and abiotic components, which further elucidates the negative effects on the above-ground properties of the crops. In addition, the consumption of these crops in the food chain revealed a potential risk to human health throughout the food chain. Moreover, microplastic pollution has the potential to induce a negative impact on agricultural production and food security by altering the physiochemical properties of the soil, microbial population, nutrient cycling, and plant growth and development. Therefore, we discussed in detail the potential hazards caused by microplastic contamination in the soil and through the consumption of food and water by humans in daily intake. Furthermore, further study is urgently required to comprehend how microplastic pollution negatively affects terrestrial ecosystems, particularly agroecosystems which drastically reduces the productivity of the crops. Our review highlights the urgent need for greater awareness, policy interventions, and technological solutions to address the emerging threat of microplastic pollution in soil and plant systems and mitigation strategies to overcome its potential impacts on human health. Based on existing studies, we have pointed out the research gaps and proposed different directions for future research.


Asunto(s)
Metales Pesados , Microplásticos , Humanos , Microplásticos/toxicidad , Suelo/química , Plásticos , Ecosistema , Metales Pesados/toxicidad , Productos Agrícolas
14.
Oral Dis ; 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38462960

RESUMEN

OBJECTIVES: To explore the effects of cathepsin K (CTSK) inhibition on type H vessel formation and alveolar bone resorption within periodontitis. METHODS: Conditioned media derived from preosteoclasts pretreated with the CTSK inhibitor odanacatib (ODN), ODN supplemented small interfering RNA targeting PDGF-BB (si-PDGF-BB), or PBS were prepared, to assess their proangiogenic effects on endothelial cells (HUVECs). A series of angiogenic-related assays were conducted to evaluate HUVEC proliferation, migration, and tube formation abilities in vitro. In addition, qRT-PCR and Western blot assays were employed to examine the expression levels of genes/proteins related to PDGF-BB/PDGFR-ß axis components. A mouse periodontitis model was established to evaluate the effects of CTSK inhibition on type H vessel formation. RESULTS: CTSK inhibition promoted PDGF-BB secretion from preosteoclasts and proliferation, migration, and tube formation activities of HUVECs in vitro. However, the conditioned medium from preosteoclasts pretreated by si-PDGF-BB impaired the angiogenic activities of HUVECs. This promoted angiogenesis function by CTSK inhibition may be mediated by the PDGF-BB/PDGFR-ß axis. Functionally, in vivo studies demonstrated that CTSK inhibition significantly accelerated type H vessel formation and alleviated bone loss within periodontitis. CONCLUSION: CTSK inhibition promotes type H vessel formation and attenuates alveolar bone resorption within periodontitis via PDGF-BB/PDGFR-ß axis.

15.
J Dairy Sci ; 107(3): 1355-1369, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37776999

RESUMEN

It is desirable to obtain high levels of viable Lacticaseibacillus paracasei, a widely used food probiotic whose antibacterial activity and potential application in milk remain largely uninvestigated. Here, we isolated and purified the L. paracasei strain XLK 401 from food-grade blueberry ferments and found that it exhibited strong antibacterial activity against both gram-positive and gram-negative foodborne pathogens, including Staphylococcus aureus, Salmonella paratyphi B, Escherichia coli O157, and Shigella flexneri. Then, we applied alternating tangential flow (ATF) technology to produce viable L. paracasei XLK 401 cells and its cell-free supernatant (CFS). Compared with the conventional fed-batch method, 22 h of ATF-based processing markedly increased the number of viable cells of L. paracasei XLK 401 to 12.14 ± 0.13 log cfu/mL. Additionally, the CFS exhibited good thermal stability and pH tolerance, inhibiting biofilm formation in the abovementioned foodborne pathogens. According to liquid chromatography-mass spectrometry analysis, organic acids were the main antibacterial components of XLK 401 CFS, accounting for its inhibition activity. Moreover, the CFS of L. paracasei XLK 401 effectively inhibited the growth of multidrug-resistant gram-positive Staph. aureus and gram-negative E. coli O157 pathogens in milk, and caused a reduction in the pathogenic cell counts by 6 to 7 log cfu/mL compared with untreated control, thus considerably maintaining the safety of milk samples. For the first time to our knowledge, ATF-based technology was employed to obtain viable L. paracasei on a large scale, and its CFS could serve as a broad-spectrum biopreservative for potential application against foodborne pathogens in milk products.


Asunto(s)
Escherichia coli O157 , Lacticaseibacillus paracasei , Animales , Leche , Antibacterianos/farmacología , Recuento de Células/veterinaria
16.
Plant Dis ; 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38902883

RESUMEN

The Fusarium head blight (FHB) caused by Fusarium graminearum is a serious fungal disease that can dramatically impact wheat production. At present, control is mainly achieved by the use of chemical fungicides. Hexaconazole (IUPAC name: 2-(2,4-dichlorophenyl)-1-(1,2,4-triazol-1-yl)hexan-2-ol) is a widely used triazole fungicide, but the sensitivity of F. graminearum to this compound has yet to be established. The current study found that the EC50 values of 83 field isolates of F. graminearum ranged between 0.06 and 4.33 µg/mL, with an average EC50 of 0.78 µg/mL. Assessment of four hexaconazole-resistant laboratory mutants of F. graminearum revealed that their mycelial growth, and pathogenicity were reduced compared to their parental isolates, and that asexual reproduction was reduced by resistance to hexaconazole. Meanwhile, the mutants appeared to be more sensitive to abiotic stress associated with SDS, and H2O2, while their tolerance of high concentration of Congo red, and Na+ and K+ increased. Molecular analysis revealed numerous point mutations in the FgCYP51 target genes that resulted in amino acid substitutions, including L92P and N123S in FgCYP51A, as well as M331V, F62L, Q252R, A412V, and V488A in FgCYP51B, and S28L, S256A, V307A, D287G and R515I in FgCYP51C, three of which (S28L, S256A, and V307A) were conserved in all of the resistant mutants. Furthermore, the expression of the FgCYP51 genes in resistant strains was found to be significantly (p < 0.05) reduced compared to their sensitive parental isolates. Positive cross-resistance was found between hexaconazole and metconazole and flutriafol, as well as with the diarylamine fungicide fluazinam, but not with propiconazole, and the phenylpyrrole fungicide fludioxonil, or with tebuconazole, which actually exhibited negative cross-resistance. These results provide valuable insight into resistant mechanisms to triazole fungicides in F. graminearum, as well as the appropriate selection of fungicide combinations for the control of FHB to ensure optimal wheat production.

17.
Int J Sport Nutr Exerc Metab ; 34(1): 54-64, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38039960

RESUMEN

Precise protein supplementation strategies for muscle improvement are still lacking. The timing or type of protein supplementation has been debated as a window of opportunity to improve muscle mass, strength, and physical performance. We conducted a network meta-analysis of randomized controlled trials with protein supplements and resistance training. PubMed, Web of Science, Cochrane Library, and SPORTDiscus databases were searched until May 1, 2023. We included 116 eligible trials with 4,711 participants that reported on 11 timing and 14 types of protein supplementation. Compared with placebo, protein supplementation after exercise (mean difference [MD]: 0.54 kg [95% confidence intervals 0.10, 0.99] for fat-free mass, MD: 0.34 kg [95% confidence intervals 0.10, 0.58] for skeletal muscle mass) and at night (MD: 2.85 kg [0.49, 5.22] for handgrip strength, MD: 12.12 kg [3.26, 20.99] for leg press strength) was most effective in improving muscle mass and strength, respectively (moderate certainty). Milk proteins (milk, whey protein, yogurt, casein, and bovine colostrum), red meat, and mixed protein were effective for gains in both muscle mass and strength (moderate certainty). No timing or type of protein showed a significant enhancement in physical performance (timed up-to-go test, 6-min walk test, and gait speed). Pre/postexercise and Night are key recommended times of protein intake to increase muscle mass and strength, respectively. Milk proteins are the preferred types of protein supplements for improving muscle mass and strength. Future randomized controlled trials that directly compare the effects of protein timing or types are needed. This trial was registered at International Prospective Register of Systematic Reviews as CRD42022358766.


Asunto(s)
Músculo Esquelético , Entrenamiento de Fuerza , Adulto , Humanos , Animales , Bovinos , Músculo Esquelético/fisiología , Fuerza Muscular/fisiología , Fuerza de la Mano , Metaanálisis en Red , Revisiones Sistemáticas como Asunto , Suplementos Dietéticos , Rendimiento Físico Funcional , Proteínas de la Leche
18.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(1): 19-24, 2024 Feb.
Artículo en Zh | MEDLINE | ID: mdl-38433626

RESUMEN

Objective To analyze the current situation of dietary diversity and caregiver self-efficacy for complementary feeding among infants and young children aged 6 to 23 months in rural Nanchong city,Sichuan province,and to explore the relationship between dietary diversity and caregiver self-efficacy. Methods Multi-stage randomized cluster sampling method was used to select infants and young children aged 6 to 23 months and their caregivers in rural areas of Nanchong city,Sichuan province as the subjects.A structured questionnaire was designed to collect the basic information of the subjects,dietary diversity,and caregiver self-efficacy for complementary feeding.Multivariate Logistic regression was adopted to analyze the relationship between the dietary diversity and caregiver self-efficacy for complementary feeding of infants and young children. Results A total of 770 pairs of infants and young children and their caregivers were included.The minimum pass rate of dietary diversity was 61.56%(474/770) for all the infants and young children and 45.00%(108/240),69.16%(287/415),and 68.70%(79/115) for the infants and young children aged 6 to 11,12 to 17,and 18 to 23 months,respectively.The results of regression analysis showed that the caregiver self-efficacy of complementary feeding was a contributing factor for qualified dietary diversity of infants and young children in the case of other confounders being controlled(OR=1.42,95%CI=1.17-1.73,P<0.001). Conclusion The dietary diversity for infants and young children in rural Nanchong city,Sichuan province needs to be improved,and caregivers with higher self-efficacy of complementary feeding are more likely to provide diversified complementary feeding for infants and young children.


Asunto(s)
Cuidadores , Autoeficacia , Niño , Lactante , Humanos , Preescolar , Dieta , China
19.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 53(2): 175-183, 2024 Apr 25.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-38531768

RESUMEN

OBJECTIVES: To investigate the safety of early antiplatelet therapy for non-cardioembolic mild stroke patients with thrombocytopenia. METHODS: Data of acute ischemic stroke patients with baseline National Institutes of Health Stroke Scale (NIHSS) score ≤3 and a platelet count <100×109/L were obtained from a multicenter register. Those who required anticoagulation or had other contraindications to antiplatelet therapy were excluded. Short-term safety outcomes were in-hospital bleeding events, while the long-term safety outcome was a 1-year all-cause death. The short-term neurological outcomes were evaluated by modified Rankin scale (mRS) score at discharge. RESULTS: A total of 1868 non-cardioembolic mild stroke patients with thrombocytopenia were enrolled. Multivariate regression analyses showed that mono-antiplatelet therapy significantly increased the proportion of mRS score of 0-1 at discharge (OR=1.657, 95%CI: 1.253-2.192, P<0.01) and did not increase the risk of intracranial hemorrhage (OR=2.359, 95%CI: 0.301-18.503, P>0.05), compared with those without antiplatelet therapy. However, dual-antiplatelet therapy did not bring more neurological benefits (OR=0.923, 95%CI: 0.690-1.234, P>0.05), but increased the risk of gastrointestinal bleeding (OR=2.837, 95%CI: 1.311-6.136, P<0.01) compared with those with mono-antiplatelet therapy. For patients with platelet counts ≤75×109/L and >90×109/L, antiplatelet therapy significantly improved neurological functional outcomes (both P<0.05). For those with platelet counts (>75-90)×109/L, antiplatelet therapy resulted in a significant improvement of 1-year survival (P<0.05). For patients even with concurrent coagulation abnormalities, mono-antiplatelet therapy did not increase the risk of various types of bleeding (all P>0.05) but improved neurological functional outcomes (all P<0.01). There was no significant difference in the occurrence of bleeding events, 1-year all-cause mortality risk, and neurological functional outcomes between aspirin and clopidogrel (all P>0.05). CONCLUSIONS: For non-cardioembolic mild stroke patients with thrombocytopenia, antiplatelet therapy remains a reasonable choice. Mono-antiplatelet therapy has the same efficiency as dual-antiplatelet therapy in neurological outcome improvement with lower risk of gastrointestinal bleeding.


Asunto(s)
Inhibidores de Agregación Plaquetaria , Accidente Cerebrovascular , Trombocitopenia , Humanos , Inhibidores de Agregación Plaquetaria/efectos adversos , Inhibidores de Agregación Plaquetaria/uso terapéutico , Trombocitopenia/tratamiento farmacológico , Trombocitopenia/complicaciones , Femenino , Masculino , Accidente Cerebrovascular/complicaciones , Anciano , Recuento de Plaquetas , Persona de Mediana Edad , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/complicaciones , Hemorragias Intracraneales/inducido químicamente
20.
Chin J Cancer Res ; 36(2): 151-166, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38751437

RESUMEN

Throughout tumorigenesis, the co-evolution of tumor cells and their surrounding microenvironment leads to the development of malignant phenotypes. Cellular communication within the tumor microenvironment (TME) plays a critical role in influencing various aspects of tumor progression, including invasion and metastasis. The release of exosomes, a type of extracellular vesicle, by most cell types in the body, is an essential mediator of intercellular communication. A growing body of research indicates that tumor-derived exosomes (TDEs) significantly expedite tumor progression through multiple mechanisms, inducing epithelial-mesenchymal transition and macrophage polarization, enhancing angiogenesis, and aiding in the immune evasion of tumor cells. Herein, we describe the formation and characteristics of the TME, and summarize the contents of TDEs and their diverse functions in modulating tumor development. Furthermore, we explore potential applications of TDEs in tumor diagnosis and treatment.

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