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1.
Redox Biol ; 73: 103190, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38744191

RESUMO

Parkinson's disease (PD) poses a significant challenge in neurodegenerative disorders, characterized by the progressive loss of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNc). The intricate mechanisms orchestrating DA neurodegeneration in PD are not fully understood, necessitating the exploration of innovative therapeutic approaches. Recent studies have implicated ferroptosis as a major contributor to the loss of DA neurons, revealing a complex interplay between iron accumulation and neurodegeneration. However, the sophisticated nature of this process challenges the conventional belief that mere iron removal could effectively prevent DA neuronal ferroptosis. Here, we report JWA, alternatively referred to as ARL6IP5, as a negative regulator of ferroptosis, capable of ameliorating DA neuronal loss in the context of PD. In this study, synchronized expression patterns of JWA and tyrosine hydroxylase (TH) in PD patients and mice were observed, underscoring the importance of JWA for DA neuronal survival. Screening of ferroptosis-related genes unraveled the engagement of iron metabolism in the JWA-dependent inhibition of DA neuronal ferroptosis. Genetic manipulation of JWA provided compelling evidence linking its neuroprotective effects to the attenuation of NCOA4-mediated ferritinophagy. Molecular docking, co-immunoprecipitation, and immunofluorescence studies confirmed that JWA mitigated DA neuronal ferroptosis by occupying the ferritin binding site of NCOA4. Moreover, the JWA-activating compound, JAC4, demonstrated promising neuroprotective effects in cellular and animal PD models by elevating JWA expression, offering a potential avenue for neuroprotection in PD. Collectively, our work establishes JWA as a novel regulator of ferritinophagy, presenting a promising therapeutic target for addressing DA neuronal ferroptosis in PD.

2.
Front Oncol ; 14: 1362160, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38725630

RESUMO

Sarcomatoid carcinoma (SC) is a rare, complex, aggressive tumor that spreads rapidly, is highly malignant, and has metastasized. Surgical resection is the primary treatment, and it usually occurs in the lungs and kidneys but rarely in the neck. Patients with advanced sarcomatoid carcinoma (SC) of the head and neck (HN) have a poor progonsis. In recent years, immune checkpoint inhibitors (ICIs) have been established as treatments for many solid tumors; however, the effectiveness of ICIs in treating SC of HN is still little recognized. We report a case study of a middle-aged woman with primary sarcomatoid carcinoma of the neck. She developed sarcomatoid carcinoma of the contralateral neck 7 months after the first surgical treatment. Subsequently, disease recurrence and metastasis occurred 8 months after the second surgery. The patient did not receive any treatment after both surgeries. The tumor showed high programmed death-ligand 1 (PD-L1) expression, with a combined positive score (CPS): 95. The patient's response to treatment was assessed as partial remission (PR) after 2 cycles of anlotinib combined with sintilimab. The patient has survived for over 2 years and remains in PR status, despite experiencing grade 2 hypothyroidism as an adverse event during treatment. The case highlights the efficacy and safety of anlotinib and sintilimab as a first-line treatment.

3.
Chembiochem ; : e202400361, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38767267

RESUMO

RNA modifications play crucial roles in regulating gene expression and cellular homeostasis.  Modulating RNA modifications, particularly by targeting the enzymes responsible for their catalysis, has emerged as a promising therapeutic strategy.  However, limitations, such as the lack of identified modifying enzymes and compensatory mechanisms, hinder targeted interventions.  Chemical approaches independent of enzymatic activity offer an alternative strategy for RNA modification modulation.  Here, we present the identification of 2-chloro-3,5-dinitrobenzoic acid as a highly effective photochemical deprenylase of i6A RNA.  This method demonstrates exceptional selectivity towards i6A, converting its substituent into a "N-doped" ozonide, which upon hydrolysis releases natural adenine.  We believe that this chemical approach will pave the way for a better understanding of RNA modification biology and the development of novel therapeutic modalities.

4.
CNS Neurosci Ther ; 30(5): e14748, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38727518

RESUMO

AIMS: To investigate the characteristics of dynamic cerebral autoregulation (dCA) after intravenous thrombolysis (IVT) and assess the relationship between dCA and prognosis. METHODS: Patients with unilateral acute ischemic stroke receiving IVT were prospectively enrolled; those who did not were selected as controls. All patients underwent dCA measurements, by quantifying the phase difference (PD) and gain, at 1-3 and 7-10 days after stroke onset. Simultaneously, two dCA-based nomogram models were established to verify the predictive value of dCA for patients with mild-to-moderate stroke. RESULTS: Finally, 202 patients who received IVT and 238 who did not were included. IVT was positively correlated with higher PD on days 1-3 and 7-10 after stroke onset. PD values in both sides at 1-3 days after stroke onset and in the affected side at 7-10 days after onset were independent predictors of unfavorable outcomes in patients who received IVT. Additionally, in patients with mild-to-moderate stroke who received IVT, the dCA-based nomogram models significantly improved the risk predictive ability for 3-month unfavorable outcomes. CONCLUSION: IVT has a positive effect on dCA in patients with acute stroke; furthermore, dCA may be useful to predict the prognosis of patients with IVT.


Assuntos
Homeostase , AVC Isquêmico , Terapia Trombolítica , Humanos , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Prognóstico , Terapia Trombolítica/métodos , Homeostase/fisiologia , Homeostase/efeitos dos fármacos , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/fisiopatologia , Fibrinolíticos/administração & dosagem , Fibrinolíticos/uso terapêutico , Circulação Cerebrovascular/fisiologia , Circulação Cerebrovascular/efeitos dos fármacos , Estudos Prospectivos , Ativador de Plasminogênio Tecidual/administração & dosagem , Ativador de Plasminogênio Tecidual/uso terapêutico , Administração Intravenosa , Valor Preditivo dos Testes , Idoso de 80 Anos ou mais , Nomogramas , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/fisiopatologia
5.
Gut Microbes ; 16(1): 2347725, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38722028

RESUMO

The gut commensal bacteria Christensenellaceae species are negatively associated with many metabolic diseases, and have been seen as promising next-generation probiotics. However, the cultured Christensenellaceae strain resources were limited, and their beneficial mechanisms for improving metabolic diseases have yet to be explored. In this study, we developed a method that enabled the enrichment and cultivation of Christensenellaceae strains from fecal samples. Using this method, a collection of Christensenellaceae Gut Microbial Biobank (ChrisGMB) was established, composed of 87 strains and genomes that represent 14 species of 8 genera. Seven species were first described and the cultured Christensenellaceae resources have been significantly expanded at species and strain levels. Christensenella strains exerted different abilities in utilization of various complex polysaccharides and other carbon sources, exhibited host-adaptation capabilities such as acid tolerance and bile tolerance, produced a wide range of volatile probiotic metabolites and secondary bile acids. Cohort analyses demonstrated that Christensenellaceae and Christensenella were prevalent in various cohorts and the abundances were significantly reduced in T2D and OB cohorts. At species level, Christensenellaceae showed different changes among healthy and disease cohorts. C. faecalis, F. tenuis, L. tenuis, and Guo. tenuis significantly reduced in all the metabolic disease cohorts. The relative abundances of C. minuta, C. hongkongensis and C. massiliensis showed no significant change in NAFLD and ACVD. and C. tenuis and C. acetigenes showed no significant change in ACVD, and Q. tenuis and Geh. tenuis showed no significant change in NAFLD, when compared with the HC cohort. So far as we know, this is the largest collection of cultured resource and first exploration of Christensenellaceae prevalences and abundances at species level.


Assuntos
Fezes , Microbioma Gastrointestinal , Humanos , Fezes/microbiologia , Clostridiales/genética , Clostridiales/metabolismo , Clostridiales/isolamento & purificação , Clostridiales/classificação , Probióticos/metabolismo , Metabolômica , Genômica , Masculino , Filogenia , Feminino , Genoma Bacteriano
6.
ACS Omega ; 9(19): 21416-21425, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38764682

RESUMO

As a critical mitotic regulator, Aurora kinase A (AURKA) is aberrantly activated in a wide range of cancers. Therapeutic targeting of AUKRA is a promising strategy for the treatment of solid tumors. In this study, we evaluated the preclinical characteristics of JAB-2485, a small-molecule inhibitor of AURKA currently in Phase I/IIa clinical trial in the US (NCT05490472). Biochemical studies demonstrated that JAB-2485 is potent and highly selective on AURKA, with subnanomolar IC50 and around 1500-fold selectivity over AURKB or AURKC. In addition, JAB-2485 exhibited favorable pharmacokinetic properties featured by low clearance and good bioavailability, strong dose-response relationship, as well as low risk for hematotoxicity and off-target liability. As a single agent, JAB-2485 effectively induced G2/M cell cycle arrest and apoptosis and inhibited the proliferation of small cell lung cancer, triple-negative breast cancer, and neuroblastoma cells. Furthermore, JAB-2485 exhibited robust in vivo antitumor activity both as monotherapy and in combination with chemotherapies or the bromodomain inhibitor JAB-8263 in xenograft models of various cancer types. Together, these encouraging preclinical data provide a strong basis for safety and efficacy evaluations of JAB-2485 in the clinical setting.

7.
Angew Chem Int Ed Engl ; : e202404660, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714487

RESUMO

Oxygen vacancies (OV) in nonmetallic plasmonic photocatalysts can decrease the energy barrier for CO2 reduction, boosting C1 intermediate production for potential C2 formation. However, their susceptibility to oxidation weakens C1 intermediate adsorption. Herein we proposed a "photoelectron injection" strategy to safeguard OV in W18O49 by creating a W18O49/ZIS (W/Z) plasmonic photocatalyst. Moreover, photoelectrons contribute to the local multi-electron environment of W18O49, enhancing the intrinsic excitation of its hot electrons with extended lifetimes, as confirmed by in-situ XPS and femtosecond transient absorption analysis. Density functional theory calculations revealed that W/Z with Ov enhances CO2 adsorption, activating *CO production, while reducing the energy barrier for *COH production (0.054 eV) and subsequent *CO-COH coupling (0.574 eV). Successive hydrogenation revealed that the free energy for *CH2CH2 hydrogenation (0.108 eV) was lower than that for *CH2CH2 desorption for C2H4 production (0.277 eV), favouring C2H6 production. Consequently, W/Z achieves an efficient C2H6 activity of 653.6 µmol g-1 h-1 under visible light, with an exceptionally high selectivity of 90.6%. This work offers a new strategy for the rational design of plasmonic photocatalysts with high selectivity for C2+ products.

8.
Front Oncol ; 14: 1375035, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38706596

RESUMO

Background: The treatment outcomes and prognosis for recurrent cervical cancer are generally poor, with a 5-year survival rate of only 10%-20%. Case presentation: In this case, the patient is a young woman who experienced a recurrence 5 years after the initial treatment of cervical cancer. Her primary symptoms were hemoptysis and dysphagia, indicative of hilar and mediastinal lymph node metastases, with further involvement of the bronchus and esophagus. Additionally, the patient also presented with tumor-associated dermatomyositis. Following combined treatment with albumin-bound paclitaxel, carboplatin, bevacizumab, and cadonilimab, the patient's tumor was effectively controlled.

9.
Glob Heart ; 19(1): 41, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38708403

RESUMO

Hypertension is a multifactorial, complex disease with high morbidity and mortality rates. Studies have found that micro-RNA 21 (miR-21) levels are significantly increased in patients with hypertension. However, other studies have reported opposite results. Therefore, the relationship between miR-21 expression and hypertension remains controversial. This meta-analysis was conducted to statistically evaluate the miR-21 levels of patients with hypertension. A literature research was conducted using Web of Science, Embase, PubMed, and CNKI. To search for titles or abstracts, 'hypertension' in combination with the terms 'miR-21,' 'microRNA-21,' or 'miRNA-21' were used as keywords. Standardized mean differences (SMD) with corresponding 95% confidence intervals (CIs) were determined from the results of the meta-analysis. In total, 12 articles were included in this meta-analysis, involving 546 cases and 436 controls. The results of the meta-analysis showed that miR-21 levels in patients with hypertension were significantly higher than those in the controls (SMD: 1.22; 95% CI [0.35, 2.09]). This meta-analysis is the first to evaluate miR-21 in patients with hypertension. MiR-21 may be a new target for the prediction and treatment of hypertension. Further high-quality studies are needed to better support the association between miR-21 and hypertension.


Assuntos
Hipertensão , MicroRNAs , Humanos , Hipertensão/epidemiologia , MicroRNAs/genética , Saúde Global , Biomarcadores/sangue
10.
Int J Pharm ; 657: 124159, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38701907

RESUMO

Inhibiting the expression of tumor necrosis factor-α (TNF-α), a pro-inflammatory cytokine widely distributed in the serum and synovial fluid, is important for managing rheumatoid arthritis (RA). Despite the good therapeutic effects of TNF-α small interfering RNA (TNF-α siRNA) in RA animal models, safe and efficient siRNA delivery systems that retain stability are lacking. We introduced a novel therapy using milk-derived exosomes(mEXOs)-encapsulated TNF-α siRNA-coated cryomicroneedle (cryoMN) patch and evaluated its efficacy via local transdermal administration through acupoints in RA treatment. The loading of TNF-α siRNAs into mEXOs was achieved by sonication, the loading rate, stability, and in vitro release of mEXOs-TNF-α siRNA were determined. The cryoMNs were prepared by micromolding, morphology, drug loading, and mechanical strength of the cryoMN array were analyzed. The loading efficiency of TNF-α siRNA was up to 21% and each cryoMN contained 39.6 ± 1.29 µg of TNF-α siRNA. Frozen sections penetrated 523 ± 63 µm deep. In vitro experiments have shown that mEXOs-TNF-α siRNA cryoMNs have good biocompatibility and inhibit the proliferation of HFLS-RA cells. In vivo pharmacodynamics studies found that general conditions, changes in microcirculation indexes, synovial histopathological changes, and expression of related proteins in the synovial tissue in RA rabbits were effectively alleviated by mEXOs-TNF-α siRNA cryoMNs. Improvement of each index at acupoints was greater than that at non-acupoints. Our findings facilitate the development of cryoMNs combined with exosomes and acupoints drug delivery for the treatment of RA. The combination of exosomes and cryoMNs will enable the development of new-generation microneedle-based treatments.

11.
J Control Release ; 370: 501-515, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38703950

RESUMO

Although nanomaterial-based nanomedicine provides many powerful tools to treat cancer, most focus on the "immunosilent" apoptosis process. In contrast, ferroptosis and immunogenic cell death, two non-apoptotic forms of programmed cell death (PCD), have been shown to enhance or alter the activity of the immune system. Therefore, there is a need to design and develop nanoplatforms that can induce multiple modes of cell death other than apoptosis to stimulate antitumor immunity and remodel the immunosuppressive tumor microenvironment for cancer therapy. In this study, a new type of multifunctional nanocomposite mainly consisting of HMME, Fe3+ and Tannic acid, denoted HFT NPs, was designed and synthesized to induce multiple modes of cell death and prime the tumor microenvironment (TME). The HFT NPs consolidate two functions into one nano-system: HMME as a sonosensitizer for the generation of reactive oxygen species (ROS) 1O2 upon ultrasound irradiation, and Fe3+ as a GSH scavenger for the induction of ferroptosis and the production of ROS ·OH through inorganic catalytic reactions. The administration of HFT NPs and subsequent ultrasound treatment caused cell death through the consumption of GSH, the generation of ROS, ultimately inducing apoptosis, ferroptosis, and immunogenic cell death (ICD). More importantly, the combination of HFT NPs and ultrasound irradiation could reshape the TME and recruit more T cell infiltration, and its combination with immune checkpoint blockade anti-PD-1 antibody could eradicate tumors with low immunogenicity and a cold TME. This new nano-system integrates sonodynamic and chemodynamic properties to achieve outstanding therapeutic outcomes when combined with immunotherapy. Collectively, this study demonstrates that it is possible to potentiate cancer immunotherapy through the rational and innovative design of relatively simple materials.

12.
J Agric Food Chem ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748811

RESUMO

Insect gustatory receptors (GRs) aid in the precise identification of deterrent or stimulant compounds associated with food, mating, and egg-laying. Thus, they are promising targets for developing efficient insecticides. Here, 61 GRs in the chemosensory organs of Spodoptera litura larvae and adults were identified. Among them, SlitGR206 exhibited larval labium (LL)-specific expression characteristics. To explore the role of SlitGR206, a bacterial expression system was established to produce high-quality double-stranded RNA (dsRNA) and suppress SlitGR206 expression in LL. Subsequent behavioral assessments revealed that SlitGR206 silencing influenced larval feeding preferences and absorption. Moreover, it was found to reduce the ability of larvae to forage the five crucial host odorants. These findings demonstrate that SlitGR206 likely plays an indirect regulatory role in host recognition, consequently affecting foraging behavior. This provides a crucial foundation for the analysis of functional diversity among insect GRs and the precise development of nucleic acid pesticides in the future.

13.
Eur J Dermatol ; 34(1): 31-39, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557456

RESUMO

The systemic immune inflammation index (SII) is an effective indicator of systemic inflammatory status. As psoriasis patients present with systemic involvement, we assessed whether SII is associated with psoriasis in adults. We used data from the National Health and Nutrition Examination Survey (NHANES) from 2003 to 2006 and 2009 to 2014. The study used a multistage sampling design that nationally represents the US population. The main outcome was the prevalence of psoriasis. SII was calculated as platelet count × neutrophil count/lymphocyte count and transformed into log2SII. Sampling weights were calculated according to the guidelines of NHANES. The cohort consisted of 13,300 participants, aged 20-59, who provided responses to their psoriasis status. Among the adults included in this study were 358 with psoriasis and 12,942 without psoriasis. Based on multivariate analysis adjusted for multiple covariates, the highest quartile of log2SII positively correlated with psoriasis relative to the lowest quartile. The subgroup analyses showed that participants in quartile 4 correlated with an increased risk of psoriasis among those aged 40 to 59 years, and among those with obesity or metabolic syndrome. Based on sensitivity analyses, the association between log2SII and psoriasis remained after excluding potential systemic medication use. Based on this cross-sectional study, SII was shown to be associated with psoriasis in the US adult population. Longitudinal monitoring of systemic inflammatory status in psoriasis patients may be necessary to prevent the recurrence of psoriasis, especially for those with obesity or metabolic syndrome.


Assuntos
Síndrome Metabólica , Psoríase , Adulto , Humanos , Inquéritos Nutricionais , Estudos Transversais , Síndrome Metabólica/complicações , Síndrome Metabólica/epidemiologia , Inflamação , Obesidade/complicações , Obesidade/epidemiologia , Psoríase/complicações , Psoríase/epidemiologia
14.
Nat Chem ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565977

RESUMO

Visible-light-driven photoredox catalysis is known to be a powerful tool for organic synthesis. Its occurrence critically depends on the twice exothermic single-electron transfer processes of photosensitizers, which are governed by the redox properties of the species involved. Hence, the inherently narrow range of redox potentials of photosensitizers inevitably constrains their further availability. Sensitization-initiated electron transfer has recently been found to effectively overcome this substantial challenge. However, feasible and practical strategies for designing such complicated catalytic systems are rather scarce. Herein we report an elaborate dual-catalyst platform, with dicyanopyrazine as a visible light photosensitizer and a pyrenyl-incorporated chiral phosphoric acid as a co-sensitizer, and we demonstrate the applicability of this sensitization-initiated electron transfer strategy in an asymmetric formal de Mayo-type reaction. The catalysis platform enables otherwise thermodynamically unfavourable electron transfer processes to close the redox cycle and allows for precise access to valuable enantioenriched 1,5-diketones with a wide substrate range.

15.
Clin Pharmacol Ther ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566457

RESUMO

There is a growing demand for the use of high-quality real-world evidence (RWE) to support regulatory decision-making worldwide and in China, which highlights the need for conducting literature reviews to evaluate the available data and evidence. This study aims to review the use of RWE in Chinese regulatory decisions and to summarize relevant regulatory and methodological considerations to inform the future use of RWE in China. We identified policy documents, technical guidance documents, and cases on official Chinese government websites and extracted their contents separately. We consulted experts from the National Medical Products Administration (NMPA) and academic institutes and searched case-related articles for enrichment. We also searched and included articles related to the use of RWE/Real-world data in Chinese regulatory decisions. Six trial versions of technical guidance documents, 7 case studies, and 40 articles related to the Chinese regulatory decisions were included in this study. Based on the technical guidance, data quality, and appropriate study design and statistical analysis are the main concerns for RWE generation. The cases and articles related to regulatory decisions revealed 9 main concerns, including data sources and applicability, data quality, strength of existing evidence, appropriate study design and statistical analysis, regulated and transparent process for analysis and evidence generation, product safety and efficacy, product characteristics and clinical needs, ethical considerations and data security, and communicate adequately with regulatory authorities. Among these concerns, data issues are central. Preliminary attempts have been made by the NMPA to promote the use of RWE, but substantial challenges still remain.

16.
World J Gastrointest Endosc ; 16(3): 117-125, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38577648

RESUMO

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a means to procure adequate specimens for histological and cytologic analysis. The ideal EUS-FNA should be safe, accurate, and have a high sample adequacy rate and low adverse events rate. In recent years, many guidelines and trials on EUS-FNA have been published. The purpose of this article is to provide an update on the influence of some of the main factors on the diagnostic efficiency of EUS-FNA as well as a rare but serious complication known as needle tract seeding.

17.
PeerJ ; 12: e17187, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38560458

RESUMO

Background: Periodontitis is a chronic inflammatory disease caused by bacterial infection in the periodontal support tissue. Visfatin, a hormone secreted mainly by adipocytes and macrophages, plays an important role in immune regulation and defense. Although studies have indicated that patients with periodontitis have significantly high serum and gingival crevicular fluid levels of visfatin, the relationship between this adipocytokine and periodontal disease remains unclear. Aim: The aim of this study was to systematically evaluate the association between visfatin levels and periodontitis. Methods: The PubMed, Web of Science, ScienceDirect, EBSCO, and Wiley Online Library databases were searched for potential studies, using "periodontitis" and "visfatin" as the keywords in the title and abstract search fields. Standardized mean difference (SMD) values with corresponding 95% confidence intervals (CIs) were determined from the results of this meta-analysis. Results: In total, 22 articles involving 456 patients with periodontitis and 394 healthy individuals (controls) were included in the meta-analysis. Visfatin levels were significantly higher in the patients with periodontitis than in the healthy individuals (SMD: 3.82, 95% CI [3.01-4.63]). Moreover, the visfatin levels were significantly lowered after periodontitis treatment (SMD: -2.29, 95% CI [-3.33 to -1.26]). Conclusion: This first-ever meta-analysis comparing visfatin levels between patients with periodontitis and healthy individuals suggests that this adipocytokine can be a diagnostic and therapeutic biomarker for periodontal disease.


Assuntos
Doenças Periodontais , Periodontite , Humanos , Adipocinas , Estudos de Casos e Controles , Nicotinamida Fosforribosiltransferase/análise
18.
BMC Oral Health ; 24(1): 425, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582842

RESUMO

BACKGROUND: Clinical scenarios frequently present challenges when patients exhibit asymmetrical mandibular atrophy. The dilemma arises: should we adhere to the conventional All-on-4 technique, or should we contemplate placing vertically oriented implants on the side with sufficient bone mass? This study aims to employ three-dimensional finite element analysis to simulate and explore the biomechanical advantages of each approach. METHODS: A finite element model, derived from computed tomography (CT) data, was utilized to simulate the nonhomogeneous features of the mandible. Three configurations-All-on-4, All-on-5-v and All-on-5-o were studied. Vertical and oblique forces of 200 N were applied unilaterally, and vertical force of 100 N was applied anteriorly to simulate different masticatory mechanisms. The maximum von Mises stresses on the implant and framework were recorded, as well as the maximum equivalent strain in the peri-implant bone. RESULTS: The maximum stress values for all designs were located at the neck of the distal implant, and the maximum strains in the bone tissue were located around the distal implant. The All-on-5-o and All-on-5-v models exhibited reduced stresses and strains compared to All-on-4, highlighting the potential benefits of the additional implant. There were no considerable differences in stresses and strains between the All-on-5-o and All-on-5-v groups. CONCLUSIONS: With the presence of adequate bone volume on one side and severe atrophy of the contralateral bone, while the "All-on-4 concept" is a viable approach, vertical implant placement optimizes the transfer of forces between components and tissues.


Assuntos
Implantes Dentários , Humanos , Fenômenos Biomecânicos , Análise de Elementos Finitos , Estresse Mecânico , Análise do Estresse Dentário/métodos , Prótese Dentária Fixada por Implante , Mandíbula/diagnóstico por imagem , Atrofia
19.
Int J Microbiol ; 2024: 7172386, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38590774

RESUMO

Atopic dermatitis is one of the most common dermatologic problems, especially in children. Given the ability of symbiotic microorganisms in modulating the immune system, probiotics administration has been studied in previous research in the management of atopic dermatitis. However, there are conflicting results between studies. In this study, we aimed to assess the effectiveness of mixed probiotics as a treatment option for atopic dermatitis induced by ovalbumin. BALB/c juvenile mice were classified and divided into the ovalbumin group, mixed probiotic group (ovalbumin + LK), and control group. Except for the control group, all mice were sensitized with ovalbumin to establish a model of atopic dermatitis. The mixed probiotics were given by gavage for 14 days. Mice body weight, skin lesions, skin inflammation, ovalbumin-specific Ig, the number of Treg and CD103+DC, and the expression level of PD-1/PD-L1 were examined. The results showed that mixed probiotics can improve body weight and alleviate skin symptoms. Mixed probiotics reduced serum Th2 inflammatory factors, eosinophils, mast cell degranulation, mast cell count, and the expression of ovalbumin-specific immunoglobulin E/G1 and increased the anti-inflammatory cytokine interleukin-10, Treg cells, CD103+DC cells, and the expression level of PD-1/PD-L1. These findings suggest that mixed probiotics could be a viable treatment option for atopic dermatitis and provide insight into the underlying mechanisms involved.

20.
Pharm Stat ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38628051

RESUMO

The meta-analysis of rare events presents unique methodological challenges owing to the small number of events. Bayesian methods are often used to combine rare events data to inform decision-making, as they can incorporate prior information and handle studies with zero events without the need for continuity corrections. However, the comparative performances of different Bayesian models in pooling rare events data are not well understood. We conducted a simulation to compare the statistical properties of four parameterizations based on the binomial-normal hierarchical model, using two different priors for the treatment effect: weakly informative prior (WIP) and non-informative prior (NIP), pooling randomized controlled trials with rare events using the odds ratio metric. We also considered the beta-binomial model proposed by Kuss and the random intercept and slope generalized linear mixed models. The simulation scenarios varied based on the treatment effect, sample size ratio between the treatment and control arms, and level of heterogeneity. Performance was evaluated using median bias, root mean square error, median width of 95% credible or confidence intervals, coverage, Type I error, and empirical power. Two reviews are used to illustrate these methods. The results demonstrate that the WIP outperforms the NIP within the same model structure. Among the compared models, the model that included the treatment effect parameter in the risk model for the control arm did not perform well. Our findings confirm that rare events meta-analysis faces the challenge of being underpowered, highlighting the importance of reporting the power of results in empirical studies.

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