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1.
Biochem Biophys Res Commun ; 710: 149881, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38583233

RESUMO

Maackia amurensis lectins serve as research and botanical agents that bind to sialic residues on proteins. For example, M. amurensis seed lectin (MASL) targets the sialic acid modified podoplanin (PDPN) receptor to suppress arthritic chondrocyte inflammation, and inhibit tumor cell growth and motility. However, M. amurensis lectin nomenclature and composition are not clearly defined. Here, we sought to definitively characterize MASL and its effects on tumor cell behavior. We utilized SDS-PAGE and LC-MS/MS to find that M. amurensis lectins can be divided into two groups. MASL is a member of one group which is composed of subunits that form dimers, evidently mediated by a cysteine residue in the carboxy region of the protein. In contrast to MASL, members of the other group do not dimerize under nonreducing conditions. These data also indicate that MASL is composed of 4 isoforms with an identical amino acid sequence, but unique glycosylation sites. We also produced a novel recombinant soluble human PDPN receptor (shPDPN) with 17 threonine residues glycosylated with sialic acid moieties with potential to act as a ligand trap that inhibits OSCC cell growth and motility. In addition, we report here that MASL targets PDPN with very strong binding kinetics in the nanomolar range. Moreover, we confirm that MASL can inhibit the growth and motility of human oral squamous cell carcinoma (OSCC) cells that express the PDPN receptor. Taken together, these data characterize M. amurensis lectins into two major groups based on their intrinsic properties, clarify the composition of MASL and its subunit isoform sequence and glycosylation sites, define sialic acid modifications on the PDPN receptor and its ability to act as a ligand trap, quantitate MASL binding to PDPN with KD in the nanomolar range, and verify the ability of MASL to serve as a potential anticancer agent.


Assuntos
Antineoplásicos , Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Humanos , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Ácido N-Acetilneuramínico/metabolismo , Maackia/química , Maackia/metabolismo , Neoplasias Bucais/patologia , Cromatografia Líquida , Ligantes , Espectrometria de Massas em Tandem , Lectinas/farmacologia , Antineoplásicos/farmacologia , Análise de Sequência , Movimento Celular
2.
Adv Mater ; : e2403281, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38661081

RESUMO

Interpenetrated metal-organic frameworks (MOFs) with non-aromatic ligands provide a unique platform for adsorption, catalysis, and sensing applications. However, non-emission and the lack of optical property tailoring make it challenging to fabricate smart responsive devices with non-aromatic interpenetrated MOFs based on ligand-centered emission. In this paper, we introduce the pressure-induced aggregation effect in non-aromatic interpenetrated Zn4O(ADC)4(Et3N)6 (IRMOF-0) nanocrystals (NCs), where carbonyl groups aggregation results in O-O distances smaller than the sum of the van der Waals radii (3.04 Å), triggering the photoluminescence turn-on behavior. It is noteworthy that the IRMOF-0 NCs display an ultra-broad emission tunability of 130 nm from deep blue (440 nm) to yellow (570 nm) upon release to ambient conditions at different pressures. The eventual retention of through-space n-π* interactions in different degrees via pressure treatment is primarily responsible for achieving a controllable multi-color emission behavior in initially non-emissive IRMOF-0 NCs. The fabricated multi-color phosphor-converted light-emitting diodes based on the pressure-treated IRMOF-0 NCs exhibit excellent thermal, chromaticity, and fatigue stability. Our proposed strategy not only imparts new vitality to non-aromatic interpenetrated MOFs but also offers new perspectives for advancements in the field of multi-color displays and daylight illumination. This article is protected by copyright. All rights reserved.

3.
J Pain Res ; 17: 1369-1380, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38600989

RESUMO

Objective: To create a deep learning (DL) model that can accurately detect and classify three distinct types of rat dorsal root ganglion neurons: normal, segmental chromatolysis, and central chromatolysis. The DL model has the potential to improve the efficiency and precision of neuron classification in research related to spinal injuries and diseases. Methods: H&E slide images were divided into an internal training set (80%) and a test set (20%). The training dataset was labeled by two pathologists using pre-defined grades. Using this dataset, a two-component DL model was developed with the first component being a convolutional neural network (CNN) that was trained to detect the region of interest (ROI) and the second component being another CNN used for classification. Results: A total of 240 lumbar dorsal root ganglion (DRG) pathology slide images from rats were analyzed. The internal testing results showed an accuracy of 93.13%, and the external dataset testing demonstrated an accuracy of 93.44%. Conclusion: The DL model demonstrated a level of agreement comparable to that of pathologists in detecting and classifying normal and segmental chromatolysis neurons, although its agreement was slightly lower for central chromatolysis neurons. Significance: DL in improving the accuracy and efficiency of pathological analysis suggests that it may have a role in enhancing medical decision-making.

4.
Chem Biodivers ; : e202301509, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594219

RESUMO

Neurodegenerative diseases are characterized by the progressive loss of selectively vulnerable populations of neurons, and many factors are involved in its causes. Neurotoxicity and oxidative stress, are the main related factors. The octapeptide Ile-Ile-Ala-Val-Glu-Ala-Gly-Cys (IEC) was identified from the microalgae Isochrysis zhanjiangensis and exhibited potential anti-oxidative stress activity. In this study, the stability of α-synaptic protein binding to IEC was modeled using molecular dynamics, and the results indicated binding stabilization within 60 ns. Oxidative stress in neurons is the major cause of α-synaptic protein congestion. Therefore, we next evaluated the protective effects of IEC against oxidative stress and neurotoxicity in 6-ohdainduced Parkinson's disease (PD) model SH-SY5Y cells in vitro. In oxidative stress, IEC appeared to increase the expression of the antioxidant enzymes HO-1 and GPX through the antioxidant pathway of Nrf2, and molecular docking of IEC with Nrf2 and GPX could generate hydrogen bonds. Regarding apoptosis, IEC protected cells by increasing the Bcl-2/Bax ratio, inhibiting the caspase cascade, acting on p53, and modulating the Jak2/Stat3 pathway. The results indicated that IEC exerted neuroprotective effects through the inhibition of α-synaptic protein aggregation and antioxidant activity. Therefore, microalgal peptides have promising applications in the pre-vention and treatment of neurodegenerative diseases.

5.
Curr Issues Mol Biol ; 46(3): 2480-2496, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38534773

RESUMO

In the present work, we evaluated the antifungal activities of two novel ebselen analogs, N-allyl-benzisoselenazol-3(2H)-one (N-allyl-bs) and N-3-methylbutylbenzisoselenazol-3(2H)-one (N-3mb-bs). Colorimetric and turbidity assays were performed to determine the minimum inhibitory concentration (MIC) of these compounds in S1 (fluconazole-sensitive) and S2 (fluconazole-resistant) strains of C. albicans. N-3mb-bs was more active than the N-allyl-bs compound. It is noteworthy that the concentration of N-3mb-bs observed to inhibit fungal growth by 50% (18.2 µM) was similar to the concentration observed to inhibit the activity of the yeast plasma membrane H+-ATPase (Pma1p) by 50% (19.6 µM). We next implemented a mouse model of vulvovaginal candidiasis (VVC) using the S1 strain and examined the mouse and yeast proteins present in the vaginal lavage fluid using proteomics. The yeast proteins detected were predominately glycolytic enzymes or virulence factors associated with C. albicans while the mouse proteins present in the lavage fluid included eosinophil peroxidase, desmocollin-1, and gasdermin-A. We then utilized the N-3mb-bs compound (12.5 mg/kg) in the mouse VVC model and observed that it significantly reduced the vaginal fungal burden, histopathological changes in vagina tissue, and expression of myeloperoxidase (MPO). All in all, the present work has identified a potentially promising drug candidate for VVC treatment.

6.
J Clin Invest ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38530355

RESUMO

The mammalian SUMO-targeted E3 Ubiquitin Ligase, Rnf4, has been reported to act as a regulator of DNA repair, but the importance of RNF4 as a tumor suppressor has not been tested. Using a conditional-knockout mouse model, we deleted Rnf4 in the B cell lineage to test the importance of RNF4 for growth of somatic cells. Although Rnf4 conditional-knockout B cells exhibited substantial genomic instability, Rnf4 deletion caused no increase in tumor susceptibility. In contrast, Rnf4 deletion extended the healthy lifespan of mice expressing an oncogenic c-myc transgene. Rnf4 activity is essential for normal DNA replication, and in its absence, there was a failure in ATR-CHK1 signaling of replication stress. Factors that normally mediate replication fork stability, including members of the Fanconi Anemia gene family and the helicases, PIF1 and RECQL5, showed reduced accumulation at replication forks in the absence of RNF4. RNF4 deficiency also resulted in an accumulation of hyper-SUMOylated proteins in chromatin, including members of the SMC5/6 complex, which contributes to replication failure by a mechanism dependent on RAD51. These findings indicate that RNF4, which shows increased expression in multiple human tumor types, is a potential target for anti-cancer therapy, especially in tumors expressing c-myc.

7.
Pharmacol Res ; 201: 107096, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38320736

RESUMO

The uncontrolled bacterial infection-induced cytokine storm and sequential immunosuppression are commonly observed in septic patients, which indicates that the activation of phagocytic cells and the efficient and timely elimination of bacteria are crucial for combating bacterial infections. However, the role of dysregulated immune cells and their disrupted function in sepsis remains unclear. Here, we found that macrophages exhibited the impaired endocytosis capabilities in sepsis by Single-cell RNA sequencing and bulk RNA sequencing. Caveolae protein Caveolin-1 (Cav-1) of macrophages was inactivated by SHP2 rapidly during Escherichia coli (E.coli) infection. Allosteric inhibitor of SHP2 effectively maintains Cav-1 phosphorylation to enhance macrophage to endocytose and eliminate bacteria. Additionally, TLR4 endocytosis of macrophage was also enhanced upon E.coli infection by SHP099, inducing an increased and rapidly resolved inflammatory response. In vivo, pretreatment or posttreatment with inhibitor of SHP2 significantly reduced the bacterial burden in organs and mortality of mice subjected E.coli infection or CLP-induced sepsis. The cotreatment of inhibitor of SHP2 with an antibiotic conferred complete protection against mortality in mice. Our findings suggest that Cav-1-mediated endocytosis and bacterial elimination may play a critical role in the pathogenesis of sepsis, highlighting inhibitor of SHP2 as a potential therapeutic agent for sepsis.


Assuntos
Cavéolas , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Sepse , Animais , Humanos , Camundongos , Bactérias , Cavéolas/metabolismo , Endocitose , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/metabolismo , Macrófagos , Proteína Tirosina Fosfatase não Receptora Tipo 11/antagonistas & inibidores , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Sepse/tratamento farmacológico , Sepse/metabolismo
8.
Biosens Bioelectron ; 251: 116125, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38359668

RESUMO

Iron is an essential element that plays critical roles in many biological/metabolic processes, ranging from oxygen transport, mitochondrial respiration, to host defense and cell signaling. Maintaining an appropriate iron level in the body is vital to the human health. Iron deficiency or overload can cause life-threatening conditions. Thus, developing a new, rapid, cost-effective, and easy to use method for iron detection is significant not only for environmental monitoring but also for disease prevention. In this study, we report an innovative Fe3+ detection strategy by using both a ligand probe and an engineered nanopore with two binding sites. In our design, one binding site of the nanopore has a strong interaction with the ligand probe, while the other is more selective toward interfering species. Based on the difference in the number of ligand DTPMPA events in the absence and presence of ferric ions, micromolar concentrations of Fe3+ could be detected within minutes. Our method is selective: micromolar concentrations of Mg2+, Ca2+, Cd2+, Zn2+, Ni2+, Co2+, Mn2+, and Cu2+ would not interfere with the detection of ferric ions. Furthermore, Cu2+, Ni2+, Co2+, Zn2+, and Mn2+ produced current blockage events with quite different signatures from each other, enabling their simultaneous detection. In addition, simulated water and serum samples were successfully analyzed. The nanopore sensing strategy developed in this work should find useful application in the development of stochastic sensors for other substances, especially in situations where multi-analyte concurrent detection is desired.


Assuntos
Técnicas Biossensoriais , Nanoporos , Humanos , Ligantes , Técnicas Biossensoriais/métodos , Íons/química , Ferro
9.
Colloids Surf B Biointerfaces ; 235: 113776, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38364520

RESUMO

Decades of research have been conducted on 10-Methacryloyloxydecyl dihydrogen phosphate (MDP) through numerous studies. The mechanisms by which its residual calcium salts benefit dentin bonding remain undetermined. The objective of the research was to investigate the role and process of remaining calcium salts in the priming procedure and their capacity for remineralization. The investigation focused on the variations in topological structure, mechanical properties, and chemical interactions between the main agent and the dentin surface. Two adhesive modes including prime-and-rinse(P&R) and prime-and-nonrinse (P&NR) utilized to evaluate the bonding performance and remineralization ability. The findings indicated that both P&R and P&NR methods could eliminate the smear-layer, uncover dentinal-tubules, and generate a textured/rough surface on the dentin. Collagen fibrils exhibited a greater presence of inorganic minerals in the P&NR mode. Compared to control group, both P&R and P&NR groups improved immediate and aging bond strength significantly (P < 0.05). AFM and 3D-STORM revealed MDP and its residual calcium salts distributed in collagen fibrils and expanded collagen matrix. In the P&NR group, TEM revealed that the dentin collagen matrix experienced some remineralization, and there was also mineralization within the collagen fibrils embedded in the bonding interface. Thus, MDP priming improved dentin bonding stability. Residual calcium salts of P&NR process can enhance topological structure of the collagen matrix and induce intrafibrillar mineralization.


Assuntos
Cálcio , Sais , Dentina , Metacrilatos/química , Colágeno/química , Teste de Materiais , Resistência à Tração
10.
J Mech Behav Biomed Mater ; 151: 106408, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38244421

RESUMO

OBJECTIVES: This study was to investigate hydroxypropyl methylcellulose (HPMC) film as a carrier for amorphous fluorinated calcium phosphate (AFCP) nanoprecursors to continuously deliver biomimetic remineralization of enamel artificial caries lesions (ACL). MATERIALS AND METHODS: The AFCP/HPMC films were comprised of 25 wt% AFCP nanoparticles and 75 wt% HPMC. They were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and biocompatibility tests. Forty enamel ACL were prepared and randomly divided into four groups (n = 10): The enamel surfaces were covered with a pure HPMC film, Tooth Mousse Plus (contains 10% CPP-ACP and 0.2% NaF), and AFCP/HPMC film, or without any things (serving as negative control). Subsequently, all samples were alternatively kept in artificial saliva and a modified pH-cycling before they were characterized by Micro-CT, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), attenuated total reflectance (ATR)-FTIR, XRD, and nanoindentation. RESULTS: After the enamel ACL was challenged by pH cycling, Tooth Mousse Plus and AFCP/HPMC film groups exhibited less lesion depth and mineral loss than the negative control and pure HPMC film groups. Additionally, the AFCP/HPMC film group revealed a highest remineralization rate of 55.34 ± 3.10 % among the all groups (p < 0.001). The SEM findings showed that the enamel ACL were densely deposited with minerals in the AFCP/HPMC film group, and the EDX results suggested a higher content of fluorine in the remineralized tissues. In particular, the AFCP/HPMC film group exhibited the best nanomechanical performance after 2 weeks of pH cycling (p < 0.05), with the hardness (H) restored from 0.29 ± 0.19 to 2.69 ± 0.70 GPa, and elastic modulus (Er) restored from 10.77 ± 5.30 to 68.83 ± 12.72 GPa. CONCLUSION: The AFCP/HPMC film might be used as a promising strategy for arresting or reversing incipient enamel caries lesions.


Assuntos
Suscetibilidade à Cárie Dentária , Cárie Dentária , Humanos , Derivados da Hipromelose , Remineralização Dentária/métodos , Fosfatos de Cálcio , Minerais , Cárie Dentária/tratamento farmacológico
11.
JCO Precis Oncol ; 8: e2300441, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38181316

RESUMO

PURPOSE: The way late-onset toxicities are managed can affect trial outcomes and participant safety. Specifically, participants often might not have completed their entire follow-up period to observe any toxicities before new participants would be recruited. We conducted a methodological review of published early-phase dose-finding clinical trials that used designs accounting for partial and complete toxicity information, aiming to understand (1) how such designs were implemented and reported and (2) if sufficient information was provided to enable the replicability of trial results. METHODS: Until March 26, 2023, we identified 141 trials using the rolling 6 design, the time-to-event continuous reassessment method (TITE-CRM), the TITE-CRM with cycle information, the TITE Bayesian optimal interval design, the TITE cumulative cohort design, and the rapid enrollment design. Clinical settings, design parameters, practical considerations, and dose-limiting toxicity (DLT) information were extracted from these published trials. RESULTS: The TITE-CRM (61, 43.3%) and the rolling 6 design (76, 53.9%) were most frequently implemented in practice. Trials using the TITE-CRM had longer DLT assessment windows beyond the first cycle compared with the rolling 6 design (52.5% v 6.6%). Most trials implementing the TITE-CRM (91.8%, 56 of 61) failed to describe essential parameters in the protocols or the study result papers. Only five TITE-CRM trials (8.2%, 5 of 61) reported sufficient information to enable replication of the final analysis. CONCLUSION: When compared with trials using the rolling 6 design, those implementing the TITE-CRM design exhibited notable deficiencies in reporting essential details necessary for reproducibility. Inadequate reporting quality of advanced model-based trial designs hinders their credibility. We provide recommendations that can improve transparency, reproducibility, and accurate interpretation of the results for such designs.


Assuntos
Teorema de Bayes , Humanos , Reprodutibilidade dos Testes
12.
Int J Nanomedicine ; 19: 1-17, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38179219

RESUMO

Objective: This study was to investigate a novel antibacterial biomimetic mineralization strategy for exploring its potential application for root canal disinfection when stabilized cerium oxide was used. Material and Methods: A biomimetic mineralization solution (BMS) consisting of cerium nitrate and dextran was prepared. Single-layer collagen fibrils, collagen membranes, demineralized dentin, and root canal system were treated with the BMS for mineralization. The mineralized samples underwent comprehensive characterization using various techniques, including transmission electron microscopy (TEM), high-resolution TEM (HRTEM), Fourier transform infrared spectroscopy (FTIR), scanning transmission electron microscopy (STEM), selected-area electron diffraction (SAED), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and micro-CT. Additionally, the antimicrobial properties of the BMS and the remineralized dentin were also analyzed with broth microdilution method, live/dead staining, and SEM. Results: Cerium ions in the BMS underwent a transformation into cerium oxide nanoparticles, which were deposited in the inter- and intra-fibrillar collagen spaces through a meticulous bottom-up process. XPS analysis disclosed the presence of both Ce (III) and Ce (IV) of the generated cerium oxides. A comprehensive examination utilizing SEM and micro-CT identified the presence of cerium oxide nanoparticles deposited within the dentinal tubules and lateral canals of the root canal system. The BMS and remineralized dentin exhibited substantial antibacterial efficacy against E. faecalis, as substantiated by assessments involving the broth dilution method and live/dead staining technique. The SEM findings revealed the cell morphological changes of deceased E. faecalis. Conclusion: This study successfully demonstrated antibacterial biomimetic mineralization as well as sealing dentinal tubules and lateral branches of root canals using cerium nitrate and dextran. This novel biomimetic mineralization could be used as an alternative strategy for root canal disinfection.


Assuntos
Cério , Cavidade Pulpar , Dentina/química , Desinfecção , Dextranos , Cério/farmacologia , Microscopia Eletrônica de Varredura , Colágeno , Antibacterianos/farmacologia
13.
BMC Pregnancy Childbirth ; 24(1): 58, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212716

RESUMO

PURPOSE: Since the unexplained in vitro fertilization failure occurs frequently, it is of great importance and clinical value to identify potential underlying predictors. This study aimed to explore whether the percentage of sperm with a small acrosome was correlated with unexplained in vitro fertilization failure. METHODS: A new acrosomal function evaluation index (the percentage of sperm with a small acrosome) was introduced into the analysis of sperm morphology. The association between the index and acrosome function by acrosin activity detection test and acrosome reaction test was investigated. In addition, the correlation with unexplained in vitro fertilization failure was further explored. Finally, the ROC curve was used to analyze the diagnostic efficacy on the failure of in vitro fertilization and the cutoff value was calculated. RESULTS: As the increasing of the percentage of sperm with a small acrosome, the value of acrosin activity, acrosome reaction rate, and in vitro fertilization rate were reduced, with a statistically significant difference (P < 0.05). The index in the low fertilization rate group was significantly higher than that in the normal fertilization rate group (P < 0.05). Finally, the results of ROC curve found that when the index was 43.5%, the sensitivity and specificity were 74.2% and 95.3%, respectively. CONCLUSION: The percentage of sperm with a small acrosome was positively correlated with unexplained in vitro fertilization failure, which could be potentially used as a prognostic index for the failure of in vitro fertilization. TRIAL REGISTRATION: [Ethics review acceptance No IIT20210339B].


Assuntos
Acrosina , Acrossomo , Masculino , Humanos , Sêmen , Espermatozoides , Fertilização In Vitro/métodos
14.
Materials (Basel) ; 16(24)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38138810

RESUMO

Ag and its alloys, when prepared by a selective laser melting (SLM) process, have a low density and poor overall performance due to their high reflectivity when the most commonly used laser (λ = 1060 nm) is used, and they have exorbitant thermal conductivity. These characteristics lead to the insufficient melting of the powders and severely limit the applications of additive manufactured silver alloys. To improve the absorption of the laser, as well as for better mechanical properties and higher resistance to sulfidation, Ag-Cu alloys with different La2O3 contents were prepared in this work using the SLM process, via the mechanical mixing of La2O3 nanoparticles with Ag-Cu alloy powders. A series of analyses and tests were conducted to study the effects of La2O3 in Ag-Cu alloys on their density, microstructure, mechanical properties, and corrosion resistance. The results revealed that the addition of La2O3 particles to Ag-Cu alloy powders improved the laser absorptivity and reduced defects during the SLM process, leading to a significant rise from 7.76 g/cm3 to 9.16 g/cm3 in the density of the Ag-Cu alloys. The phase composition of the Ag-Cu alloys prepared by SLM was Silver-3C. La2O3 addition had no influence on the phase composition, but refined the grains of the Ag-Cu alloys by inhibiting the growth of columnar grains during the SLM process. No remarkable preferred orientation existed in all the samples prepared with or without La2O3. An upwards trend was achieved in the hardness of the Ag-Cu alloy by increasing the contents of La2O3 from 0 to 1.2%, and the average hardness was enhanced significantly, from 0.97 GPa to 2.88 GPa when the alloy contained 1.2% La2O3 due to the reduced pore defects and the refined grains resulting from the effects of the La2O3. EIS and PD tests of the samples in 1% Na2S solution proved that La2O3 addition improved the corrosion resistance of the Ag-Cu alloys practically and efficaciously. The samples containing La2O3 exhibited higher impedance values and lower corrosion current densities.

15.
BMC Med Res Methodol ; 23(1): 301, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38114931

RESUMO

BACKGROUND: To demonstrate bioequivalence between two drug formulations, a pilot trial is often conducted prior to a pivotal trial to assess feasibility and gain preliminary information about the treatment effect. Due to the limited sample size, it is not recommended to perform significance tests at the conventional 5% level using pilot data to determine if a pivotal trial should take place. Whilst some authors suggest to relax the significance level, a Bayesian framework provides an alternative for informing the decision-making. Moreover, a Bayesian approach also readily permits possible incorporation of pilot data in priors for the parameters that underpin the pivotal trial. METHODS: We consider two-sequence, two-period crossover designs that compare test (T) and reference (R) treatments. We propose a robust Bayesian hierarchical model, embedded with a scaling factor, to elicit a Go/No-Go decision using predictive probabilities. Following a Go decision, the final analysis to formally establish bioequivalence can leverage both the pilot and pivotal trial data jointly. A simulation study is performed to evaluate trial operating characteristics. RESULTS: Compared with conventional procedures, our proposed method improves the decision-making to correctly allocate a Go decision in scenarios of bioequivalence. By choosing an appropriate threshold, the probability of correctly (incorrectly) making a No-Go (Go) decision can be ensured at a desired target level. Using both pilot and pivotal trial data in the final analysis can result in a higher chance of declaring bioequivalence. The false positive rate can be maintained in situations when T and R are not bioequivalent. CONCLUSIONS: The proposed methodology is novel and effective in different stages of bioequivalence assessment. It can greatly enhance the decision-making process in bioequivalence trials, particularly in situations with a small sample size.


Assuntos
Projetos de Pesquisa , Humanos , Teorema de Bayes , Simulação por Computador , Tamanho da Amostra , Equivalência Terapêutica , Ensaios Clínicos como Assunto
16.
Opt Express ; 31(22): 35937-35947, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-38017754

RESUMO

Multiple surface lattice resonances generated with nanoparticle arrays are promising to enhance light-matter interactions at different spectral positions simultaneously, and it is important to tailor these resonances to desired frequencies for practical applications such as multi-modal nanolasing. To this end, this study proposes to generate multiple surface lattice resonances using overlapping nanoparticle arrays with different lattice spacing. Both full-wave numerical simulations and analytical coupled dipole approximation calculations reveal that for the overlapping structures composed with two different gold nanosphere arrays, both surface lattice resonances for the element structures are effectively excited. Considering that the optical responses are governed by the dipole-dipole interactions between the nanoparticles, it is interesting to find that the multiple surface lattice resonances are almost invariant by adjusting the relative shifts between the two arrays, which can be useful to tailor the high-quality factor resonances to desired spectral positions. In addition, due to the same reason, it is also shown that the multiple surface lattice resonances can be further finely tuned by selectively removing specific nanoparticles in the array. We anticipate that the tolerance to generate multiple surface lattice resonances and the flexible tunability make the overlapping nanoparticle arrays useful to design high performance linear and nonlinear nanophotonic devices.

17.
Chin J Physiol ; 66(5): 359-364, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37929347

RESUMO

As previously demonstrated, serum beta-human chorionic gonadotropin (ß-hCG) is linked to identifying early gestational abnormalities. This research was aimed at investigating the correlation between serum ß-hCG levels and thyroid metabolic function in pregnant women with hyperemesis gravidarum (HG). Ninety-one pregnant women with HG were selected as the study group and divided into early pregnancy (EP), mid-pregnancy (MP), and late pregnancy (LP) groups according to their gestational weeks, while 84 normal pregnant women were selected as the control group. Venous blood was collected from pregnant women in both groups and serum ß-hCG levels were measured by chemiluminescent immunoassay. The levels of free thyroxine (FT4), free triiodothyronine (FT3), thyroid-stimulating hormone (TSH), thyroid peroxidase antibody (TPOAb), thyroid-stimulating hormone receptor antibody (TRAb), and thyroglobulin antibody (TgAb) were tested by chemiluminescent microparticle immunoassay. Visual analog scale (VAS) scores were utilized to assess the degree of HG. Pearson analysis was implemented to measure the correlations between serum ß-hCG levels and serum FT3, FT4, TSH, TPOAb, TRAb, TgAb, as well as VAS scores and the correlations between ß-hCG, FT3, FT4, TSH, TPOAb, TRAb, TgAb, as well as VAS scores and gestation period. The receiver operating characteristic (ROC) curve was plotted to analyze the diagnostic values of thyroid hormones, thyroid-related antibodies, and ß-hCG levels for HG. Versus those in the control group, ß-hCG, FT3, FT4, TPOAb, TRAb, TgAb levels, and VAS scores were higher and TSH levels were lower in the study group. Versus those in the EP group, ß-hCG, FT3, FT4, TPOAb, TRAb, TgAb levels, and VAS scores of pregnant women in the MP and LP groups were decreased, and TSH levels were increased. Serum ß-hCG levels of pregnant women with HG were positively correlated with FT3, FT4, TPOAb, TRAb, TgAb, and VAS scores and negatively correlated with TSH levels. Serum ß-hCG, FT3, FT4, TPOAb, TRAb, TgAb levels, and VAS scores of pregnant women with HG had a negative correlation with the gestation period, while TSH levels had a positive correlation with the gestation period. The ROC curve analysis showed that ß-hCG and thyroid function-related indicators were of high clinical values in the diagnosis of HG. Collectively, our article suggests that serum ß-hCG expression of pregnant women with HG is abnormally elevated and closely related to the degree of HG and hyperthyroidism. In addition, ß-hCG and thyroid function-related indicators have certain diagnostic efficacy for HG.


Assuntos
Hiperêmese Gravídica , Gestantes , Humanos , Feminino , Gravidez , Glândula Tireoide , Tireotropina , Gonadotropina Coriônica
18.
bioRxiv ; 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37732252

RESUMO

Histone acetyltransferases KAT2A and KAT2B are paralogs highly expressed in the intestinal epithelium, but their functions are not well understood. In this study, double knockout of murine Kat2 genes in the intestinal epithelium was lethal, resulting in robust activation of interferon signaling and interferon-associated phenotypes including the loss of intestinal stem cells. Use of pharmacological agents and sterile organoid cultures indicated a cell-intrinsic double-stranded RNA trigger for interferon signaling. Acetyl-proteomics and dsRIP-seq were employed to interrogate the mechanism behind this response, which identified mitochondria-encoded double-stranded RNA as the source of intrinsic interferon signaling. Kat2a and Kat2b therefore play an essential role in regulating mitochondrial functions as well as maintaining intestinal health.

19.
Chem Sci ; 14(33): 8962-8969, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37621429

RESUMO

The integration of high activity, selectivity and stability in one electrocatalyst is highly desirable for electrochemical CO2 reduction (ECR), yet it is still a knotty issue. The unique electronic properties of high-nuclear clusters may bring about extraordinary catalytic performance; however, construction of a high-nuclear structure for ECR remains a challenging task. In this work, a family of calix[8]arene-protected bismuth-oxo clusters (BiOCs), including Bi4 (BiOC-1/2), Bi8Al (BiOC-3), Bi20 (BiOC-4), Bi24 (BiOC-5) and Bi40Mo2 (BiOC-6), were prepared and used as robust and efficient ECR catalysts. The Bi40Mo2 cluster in BiOC-6 is the largest metal-oxo cluster encapsulated by calix[8]arenes. As an electrocatalyst, BiOC-5 exhibited outstanding electrochemical stability and 97% Faraday efficiency for formate production at a low potential of -0.95 V vs. RHE, together with a high turnover frequency of up to 405.7 h-1. Theoretical calculations reveal that large-scale electron delocalization of BiOCs is achieved, which promotes structural stability and effectively decreases the energy barrier of rate-determining *OCHO generation. This work provides a new perspective for the design of stable high-nuclear clusters for efficient electrocatalytic CO2 conversion.

20.
Br J Pharmacol ; 180(23): 3059-3070, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37501600

RESUMO

BACKGROUND AND PURPOSE: Pruritic dermatitis is a disease with a considerable unmet need for treatment and appears to present with not only epidermal but also peripheral neuronal complications. Here, we propose a novel pharmacological modulation targeting both peripheral dorsal root ganglion (DRG) sensory neurons and skin keratinocytes. GPR35 is an orphan G-protein-coupled receptor expressed in DRG neurons and has been predicted to downregulate neuronal excitability when activated. Modulator information is currently increasing for GPR35, and pamoic acid (PA), a salt-forming agent for drugs, has been shown to be an activator solely specific for GPR35. Here, we investigated its effects on dermatitic pathology. EXPERIMENTAL APPROACH: We confirmed GPR35 expression in peripheral neurons and tissues. The effect of PA treatment was pharmacologically evaluated in cultured cells in vitro and in in vivo animal models for acute and chronic pruritus. KEY RESULTS: Local PA application mitigated acute non-histaminergic itch and, consistently, obstructed DRG neuronal responses. Keratinocyte fragmentation under dermatitic simulation was also dampened following PA incubation. Chronic pruritus in 1-chloro-2,4-dinitrobenzene and psoriasis models were also moderately but significantly reversed by the repeated applications of PA. Dermatitic scores in the 1-chloro-2,4-dinitrobenzene and psoriatic models were also improved by its application, indicating that it is beneficial for mitigating disease pathology. CONCLUSION AND IMPLICATIONS: Our findings suggest that pamoic acid activation of peripheral GPR35 can contribute to the improvement of pruritus and its associated diseases.


Assuntos
Dermatite , Dinitroclorobenzeno , Animais , Dinitroclorobenzeno/metabolismo , Dinitroclorobenzeno/farmacologia , Prurido/tratamento farmacológico , Prurido/metabolismo , Pele/metabolismo , Dermatite/metabolismo , Gânglios Espinais/metabolismo
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