Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 620
Filtrar
1.
Nature ; 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38776962

RESUMEN

AMPylation is a posttranslational modification that generally modifies amino acid side chains of proteins with adenosine monophosphate (AMP)1,2. Here we report that with ATP as the ligand and actin as the host activator, the effector protein LnaB of Legionella pneumophila exhibits AMPylase activity toward the phosphoryl group of phosphoribose on PRR42-Ub that is generated by the SidE family effectors and deubiquitinases DupA/B in an E1/E2-independent ubiquitination process3-7. The product of LnaB is further hydrolyzed by an ADP-ribosyl hydrolase, MavL, to be Ub, thereby preventing accumulation of PRR42-Ub and ADPRR42-Ub and protecting the canonical ubiquitination in host cells. LnaB represents a large family of AMPylases adopting a common structural fold, which is distinct from those of the previously known AMPylases, in bacterial pathogens of more than 20 species. Moreover, LnaB also exhibits robust phosphoryl AMPylase activity toward phosphorylated residues and produces unique ADPylation modification in proteins. During infection, LnaB AMPylates the conserved phosphorylated tyrosine residues in the activation loop of the Src family kinases8,9, which dampens the host downstream phosphorylation signaling. Structural studies revealed the actin-dependent activation and catalytic mechanisms of the LnaB family of AMPylases. This study presents an unprecedented regulation and molecular mechanism in bacterial pathogenesis and protein phosphorylation.

2.
Front Bioeng Biotechnol ; 12: 1374352, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38694621

RESUMEN

Background: The treatment of patellar tendon injury has always been an unsolved problem, and mechanical characterization is very important for its repair and reconstruction. Elastin is a contributor to mechanics, but it is not clear how it affects the elasticity, viscoelastic properties, and structure of patellar tendon. Methods: The patellar tendons from six fresh adult experimental pigs were used in this study and they were made into 77 samples. The patellar tendon was specifically degraded by elastase, and the regional mechanical response and structural changes were investigated by: (1) Based on the previous study of elastase treatment conditions, the biochemical quantification of collagen, glycosaminoglycan and total protein was carried out; (2) The patellar tendon was divided into the proximal, central, and distal regions, and then the axial tensile test and stress relaxation test were performed before and after phosphate-buffered saline (PBS) or elastase treatment; (3) The dynamic constitutive model was established by the obtained mechanical data; (4) The structural relationship between elastin and collagen fibers was analyzed by two-photon microscopy and histology. Results: There was no statistical difference in mechanics between patellar tendon regions. Compared with those before elastase treatment, the low tensile modulus decreased by 75%-80%, the high tensile modulus decreased by 38%-47%, and the transition strain was prolonged after treatment. For viscoelastic behavior, the stress relaxation increased, the initial slope increased by 55%, the saturation slope increased by 44%, and the transition time increased by 25% after enzyme treatment. Elastin degradation made the collagen fibers of patellar tendon become disordered and looser, and the fiber wavelength increased significantly. Conclusion: The results of this study show that elastin plays an important role in the mechanical properties and fiber structure stability of patellar tendon, which supplements the structure-function relationship information of patellar tendon. The established constitutive model is of great significance to the prediction, repair and replacement of patellar tendon injury. In addition, human patellar tendon has a higher elastin content, so the results of this study can provide supporting information on the natural properties of tendon elastin degradation and guide the development of artificial patellar tendon biomaterials.

3.
Nat Commun ; 15(1): 3890, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38719850

RESUMEN

Shigella flexneri is a Gram-negative bacterium causing severe bloody dysentery. Its pathogenesis is largely dictated by a plasmid-encoded type III secretion system (T3SS) and its associated effectors. Among these, the effector OspG has been shown to bind to the ubiquitin conjugation machinery (E2~Ub) to activate its kinase activity. However, the cellular targets of OspG remain elusive despite years of extensive efforts. Here we show by unbiased phosphoproteomics that a major target of OspG is CAND1, a regulatory protein controlling the assembly of cullin-RING ubiquitin ligases (CRLs). CAND1 phosphorylation weakens its interaction with cullins, which is expected to impact a large panel of CRL E3s. Indeed, global ubiquitome profiling reveals marked changes in the ubiquitination landscape when OspG is introduced. Notably, OspG promotes ubiquitination of a class of cytoskeletal proteins called septins, thereby inhibiting formation of cage-like structures encircling cytosolic bacteria. Overall, we demonstrate that pathogens have evolved an elaborate strategy to modulate host ubiquitin signaling to evade septin-cage entrapment.


Asunto(s)
Proteínas Bacterianas , Septinas , Shigella flexneri , Transducción de Señal , Ubiquitina , Ubiquitinación , Shigella flexneri/metabolismo , Shigella flexneri/patogenicidad , Septinas/metabolismo , Septinas/genética , Humanos , Ubiquitina/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Fosforilación , Interacciones Huésped-Patógeno , Células HeLa , Proteínas Cullin/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Células HEK293 , Disentería Bacilar/microbiología , Disentería Bacilar/metabolismo
4.
J Cancer ; 15(10): 3152-3153, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38706919

RESUMEN

[This corrects the article DOI: 10.7150/jca.53385.].

5.
Basic Clin Androl ; 34(1): 9, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38711076

RESUMEN

BACKGROUND: Only a few cases have been reported about active foreign body implantation in the cavernous body of the penis. CASE PRESENTATION: A 47-year-old man inserted two needles from the glans penis into the bilateral penile sponge body. Subsequently, two needles migrated through the penile cavernous body into the pelvic cavity. Attempts to remove the needles through the penis were unsuccessful. Eventually, after a duration exceeding one month, the displaced needles were removed in stages from the buttocks. CONCLUSION: A few cases of intracavernosal-injection-therapy-associated needle breakage and retention have been reported globally. And this is the first case in China documenting the migration of foreign bodies within the penile region. In this condition, it is of utmost importance to engage the expertise of experienced andrologists to minimize the risk of excessive manipulation, thereby ensuring that inadvertent deep penetration of the needle into the penile tissue is prevented. In case the foreign body has migrated deeper into the tissues and the patient does not exhibit any specific symptoms or risks of macrovascular injury-related bleeding, close surveillance of its movement can be implemented. Surgical intervention can be initiated once the foreign body has reached a suitable position. Moreover, a psychiatric evaluation should be recommended for patient to discover any underlying mental health disorders.


RéSUMé: CONTEXTE: Seuls quelques cas ont été rapportés concernant l'implantation active d'un corps étranger dans le corps caverneux du pénis. PRéSENTATION DU CAS: Un homme de 47 ans a inséré deux aiguilles, par le gland du pénis, dans les corps spongieux du pénis. Par la suite, les deux aiguilles ont migré à travers le corps caverneux du pénis jusque dans la cavité pelvienne. Les tentatives pour retirer les aiguilles à travers le pénis ont été infructueuses. Finalement, après une durée de plus d'un mois, les aiguilles déplacées ont été retirées, par étapes, au niveau des fesses. CONCLUSION: Quelques cas de rupture et de rétention d'aiguille associés au traitement par injection intracaverneuse ont été signalés dans le monde. Il s'agit ici du premier cas en Chine qui documente la migration de corps étrangers dans la région du pénis. Dans cette situation, il est de la plus haute importance de faire appel à l'expertise d'andrologues expérimentés pour minimiser le risque de manipulation excessive, garantissant ainsi que la pénétration profonde par inadvertance de l'aiguille dans le tissu pénien est prévenue. Dans le cas où le corps étranger a migré plus profondément dans les tissus et que le patient ne présente pas de symptômes spécifiques ou de risques de saignements liés à une lésion macrovasculaire, une surveillance étroite du mouvement du corps étranger peut être mise en œuvre. L'intervention chirurgicale peut être initiée une fois que le corps étranger a atteint une position appropriée. Enfin, une évaluation psychiatrique devrait être recommandée à la recherche de tout trouble sous-jacent de santé mentale.

6.
J Ethnopharmacol ; 330: 118229, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-38670403

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Thymus quinquecostatus Celak., a member of thymus genus in Lamiaceae family, has been used as a folk medicine for relieving exterior syndrome and alleviating pain in China. The polyphenol-rich fraction (PRF) derived from Thymus quinquecostatus Celak. had been validated that it can protect cerebral ischemia-reperfusion injury (CIRI) by activating Keap1/Nrf2/HO-1 signaling pathway. AIM OF THIS STUDY: To explore effective components and their pharmacokinetic and pharmacodynamic characteristics as well as possible mechanisms of PRF in treating CIRI. MATERIALS AND METHODS: Normal treated group (NTG) and tMCAO model treated group (MTG) rats were administrated PRF intragastrically. The prototype components and metabolites of PRF in plasma and brain were analyzed by the UPLC-Q-Exactive Orbitrap MSn method. Subsequently, the pharmacokinetics properties of indicative components were performed based on HPLC-QQQ-MS/MS. SOD and LDH activities were determined to study the pharmacodynamic (PD) properties of PRF. The PK-PD relationship of PRF was constructed. In addition, the effect of PRF on endogenous metabolites in plasma and brain was investigated using metabolomic method. RESULTS: Salvianic acid A, caffeic acid, rosmarinic acid, scutellarin, and apigenin-7-O-glucuronide were selected as indicative components based on metabolic analysis. The non-compartmental parameters were calculated for indicative components in plasma and brain of NTG and MTG rats. Furthermore, single-component and multi-component PK-PD modeling involved Emax, Imax PD models for effect indexes were fitted as well as ANN models were established, which indicated that these components can work together to regulate SOD and LDH activities in plasma and SOD activity in brain tissue to improve CIRI. Additionally, PRF may ameliorate CIRI by regulating the disorder of endogenous metabolites in lipid metabolism, amino acid metabolism, and purine metabolism pathways in vivo, among which lipid metabolism and purine metabolism are closely related to oxidative stress. CONCLUSION: The PK-PD properties of effect substances and mechanisms of PRF anti-CIRI were further elaborated. The findings provide a convincing foundation for the application of T. quinquecostatus Celak. in the maintenance of human health disorders.


Asunto(s)
Metabolómica , Polifenoles , Ratas Sprague-Dawley , Daño por Reperfusión , Thymus (Planta) , Animales , Masculino , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/metabolismo , Thymus (Planta)/química , Polifenoles/farmacología , Polifenoles/farmacocinética , Ratas , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Extractos Vegetales/farmacología , Extractos Vegetales/farmacocinética , Encéfalo/metabolismo , Encéfalo/efectos de los fármacos , Modelos Animales de Enfermedad , Isquemia Encefálica/tratamiento farmacológico , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/farmacocinética , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/farmacocinética
8.
Nat Microbiol ; 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38649411

RESUMEN

The cyclic-oligonucleotide-based anti-phage signalling system (CBASS) is a type of innate prokaryotic immune system. Composed of a cyclic GMP-AMP synthase (cGAS) and CBASS-associated proteins, CBASS uses cyclic oligonucleotides to activate antiviral immunity. One major class of CBASS contains a homologue of eukaryotic ubiquitin-conjugating enzymes, which is either an E1-E2 fusion or a single E2. However, the functions of single E2s in CBASS remain elusive. Here, using biochemical, genetic, cryo-electron microscopy and mass spectrometry investigations, we discover that the E2 enzyme from Serratia marcescens regulates cGAS by imitating the ubiquitination cascade. This includes the processing of the cGAS C terminus, conjugation of cGAS to a cysteine residue, ligation of cGAS to a lysine residue, cleavage of the isopeptide bond and poly-cGASylation. The poly-cGASylation activates cGAS to produce cGAMP, which acts as an antiviral signal and leads to cell death. Thus, our findings reveal a unique regulatory role of E2 in CBASS.

9.
Ther Adv Med Oncol ; 16: 17588359241230752, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38425989

RESUMEN

Background: Patients with initially unresectable colorectal cancer liver metastases (IU-CRLM) might benefit from using an effective systemic treatment followed by resection of liver metastases but the curative success rate is quite low. Indeed, nearly one-third of patients exhibit early recurrence within the first 6 months after surgery, and these individuals often have poor overall survival. Objectives: This study aims to clarify the application value of serial circulating tumor DNA (ctDNA) analysis in predicting the clinical outcome of IU-CRLM patients following liver metastasectomy. Design: A retrospective study was conducted on a cohort of patients with IU-CRLM between February 2018 and April 2021. Methods: Plasma samples at different time points during CRLM treatment [baseline (BL), preoperation (PRE), postoperation (POST), end-of-treatment (EOT), and progressive disease (PD)] were retrospectively collected from patients with initially unresectable CRLM enrolled at the Sun Yat-sen University Cancer Center. Dynamic changes of SEPTIN 9 (SEPT9) and Neuropeptide Y (NPY) methylated circulating tumor DNA (MetctDNA) levels in serial plasma samples were detected using droplet-digital PCR (ddPCR). Results: SEPT9 and NPY genes were hypermethylated in colon cancer cell lines and tissues while no difference was observed between primary and metastatic tumors. Patients with MetctDNA positive at POST or EOT had significantly lower recurrence-free survival (RFS) compared to patients with MetctDNA negative at these time points [POST: Hazard ratio (HR) 9.44, 95% confidence interval (CI) 5.15-17.30, p < 0.001; EOT: HR 11.48, 95% CI 3.27-40.31, p < 0.001]. Multivariate analysis demonstrated that POST (OR 33.96, 95% CI 4.03-286.10, p = 0.001) and EOT (OR 18.36, 95% CI 1.14-295.71, p = 0.04) MetctDNA was an independent risk factor for early recurrence. Time-dependent receiver operating characteristic curve (T-ROC) analysis revealed that area under the curve (AUC) value was greatest at the relapse time point of 6 months post-intervention, with POST-AUC and EOT-AUC values of 0.74 (95% CI 0.66-0.81) and 0.73 (95% CI 0.53-0.94), respectively. Serial MetctDNA analysis showed that RFS was significantly lower in patients with no MetctDNA clearance compared with those with MetctDNA clearance (HR 26.05, 95% CI 4.92-137.81, p < 0.001). Conclusion: Our study confirmed that serial ctDNA analysis of NPY and SEPT9 gene methylation could effectively predict early recurrence in IU-CRLM patients, especially at POST and EOT.

10.
Heliyon ; 10(5): e26376, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38434369

RESUMEN

Background: Since 2019, Perampanel (PER) has been endorsed in China as an adjunctive treatment for focal seizures, both with and without impaired awareness, and for the transition from focal to bilateral tonic-clonic seizures. Limited research exists regarding the efficacy of PER in treating post-stroke epilepsy (PSE) in China. Empirical studies are essential to guide treatment protocols. We conducted a retrospective study to assess the efficacy and tolerability of PER in 58 PSE patients treated between October 2019 and July 2023. Method: This study encompassed 58 patients with PSE, treated with PER either as monotherapy or as part of adjunctive therapy, and underwent follow-up for a minimum duration of 6 months. The study assessed changes in seizure frequency, adverse events (AEs), drug retention rate, maintenance dose, and adverse reactions following PER treatment. Results: The study included 58 PSE patients, with 60.3% males and 39.7% females, ranging in age from 18 to 89, mostly within the 61-70 age group. Ischemic strokes constituted 58.6% of cases, while hemorrhagic strokes accounted for 41.4%. Focal seizures, either with or without impaired awareness, were noted in 62.1% of patients, and a transition from focal to bilateral tonic-clonic seizures was seen in 32.8%. The retention rates for PER at 3 and 6 months stood at 94.8% and 84.5% respectively, and the most commonly administered maintenance dose was 4 mg/day (41.28%). In the adjunctive therapy group, efficacy rates were 66.7% at 3 months and 78.6% at 6 months, compared to 80.0% at 3 months and 85.7% at 6 months in the monotherapy group. In the efficacy analysis, with a criterion of ≥50% reduction in seizure frequency, the overall efficacy rates at 3 and 6 months were 69.1% and 79.6%, respectively. Adverse reactions occurred in 46.6% of patients, primarily involving irritability and somnolence (both 27.6%), with no marked difference in incidence between the adjunctive and monotherapy groups (P > 0.05). Conclusion: PER exhibits favorable efficacy and tolerability in Chinese PSE patients, possibly at lower doses.

11.
iScience ; 27(3): 109281, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38455972

RESUMEN

Alzheimer's disease (AD) is the most common neurodegenerative disease often associated with olfactory dysfunction. Aß is a typical AD hall marker, but Aß-induced molecular alterations in olfactory memory remain unclear. In this study, we used a 5xFAD mouse model to investigate Aß-induced olfactory changes. Results showed that 4-month-old 5xFAD have olfactory memory impairment accompanied by piriform cortex neuron activity decline and no sound or working memory impairment. In addition, synapse and glia functional alteration is consistent across different ages at the proteomic level. Microglia and astrocyte specific proteins showed strong interactions in the conserved co-expression network module. Moreover, this interaction declines only in mild cognitive impairment patients in human postmortem brain proteomic data. This suggests that astrocytes-microglia interaction may play a leading role in the early stage of Aß-induced olfactory memory impairment, and the decreasing of their synergy may accelerate the neurodegeneration.

12.
Int Wound J ; 21(3): e14676, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38439163

RESUMEN

To evaluate the effect of predictive nursing interventions on pressure ulcers in elderly bedridden patients by meta-analysis. Applied computer searches of PubMed, Embase, Google Scholar, Cochrane Library, China National Knowledge Infrastructure and Wanfang databases for randomised controlled trials (RCTs) on the effect of predictive nursing in preventing pressure ulcers in elderly bedridden patients from the database inception to November 2023. Two researchers independently screened the literature, extracted data and performed quality assessment based on inclusion and exclusion criteria. Stata 17.0 software was utilised for data analysis. Eighteen RCTs involving 6504 patients were finally included. The analysis revealed the implementation of predictive nursing interventions had a significant advantage in reducing the incidence of pressure ulcers in elderly bedridden patients compared with conventional nursing (odds ratio [OR] = 0.20, 95% confidence interval [CI]: 0.15-0.28, p < 0.001), while the patients' satisfaction with nursing care was higher (OR = 3.70, 95% CI: 2.99-4.57, p < 0.001). This study shows that the implementation of a predictive nursing interventions for elderly bedridden patients can effectively reduce the occurrence of pressure ulcers and significantly improve patients' satisfaction with nursing care, which is worthy of clinical promotion and application.


Asunto(s)
Personas Encamadas , Úlcera por Presión , Anciano , Humanos , China , Análisis de Datos , Bases de Datos Factuales , Úlcera por Presión/enfermería , Úlcera por Presión/terapia
13.
BMC Neurol ; 24(1): 97, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38494491

RESUMEN

OBJECTIVE: To investigate the factors associated with brain frailty and the effect of brain frailty in patients with anterior circulation large artery occlusion (AC-LAO). METHODS: 1100 patients with AC-LVO consecutively admitted to the Second Hospital of Hebei Medical University, North China between June 2016 and April 2018 were retrospectively analyzed. The variables associated with brain frailty and stroke outcome were analyzed by ANOVA analysis, the Mann-Whitney U test and multiple linear regression. Based on previous research. Brain frailty score comprises 1 point each for white matter hyperintensity (WMH), old infarction lesions, and cerebral atrophy among 983 participants with baseline brain magnetic resonance imaging or computed tomography. RESULTS: Among AC-LAO participants, baseline brain frailty score ≥ 1 was common (750/983, 76.3%). Duration of hypertension > 5 years (mean difference [MD] 0.236, 95% CI 0.077, 0.395, p = 0.004), multiple vessel occlusion (MD 0.339, 95% CI 0.068, 0.611, p = 0.014) and basal ganglia infarction (MD -0.308, 95% CI -0.456, -0.160, p < 0.001) were independently associated with brain frailty score. Brain frailty score was independently associated with stroke events, and higher brain frailty scores were associated with higher rates of stroke events (p < 0.001). However, brain frailty has no independent effect on short-term outcome of ACI in AC-LAO patients. CONCLUSIONS: In AC-LAO patients, older age, duration of hypertension > 5 years, and multiple vessel occlusion influenced the brain frailty score. Brain frailty score was independently associated with the occurrence of stroke events in AC-LAO patients.


Asunto(s)
Isquemia Encefálica , Fragilidad , Hipertensión , Accidente Cerebrovascular , Humanos , Estudios Retrospectivos , Fragilidad/complicaciones , Fragilidad/epidemiología , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/epidemiología , Encéfalo , Arterias , Infarto
14.
Heliyon ; 10(5): e26673, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38463867

RESUMEN

Background and objective: Cerebral edema (CED) is a serious complication of acute ischemic stroke (AIS), especially in patients with large hemispheric infarction (LHI). Herein, a deep learning-based approach is implemented to extract CSF from T2-Weighted Imaging (T2WI) and evaluate the relationship between quantified cerebrospinal fluid and outcomes. Methods: Patients with acute LHI who underwent magnetic resonance imaging (MRI) were included. We used a deep learning algorithm to segment the CSF from T2WI. The hemispheric CSF ratio was calculated to evaluate its relationship with the degree of brain edema and prognosis in patients with LHI. Results: For the 93 included patients, the left and right cerebrospinal fluid regions were automatically extracted with a mean Dice similarity coefficient of 0.830. Receiver operating characteristic analysis indicated that hemispheric CSF ratio was an accurate marker for qualitative severe cerebral edema (area under receiver-operating-characteristic curve 0.867 [95% CI, 0.781-0.929]). Multivariate logistic regression analysis of functional prognosis showed that previous stroke (OR = 5.229, 95% CI 1.013-26.984), ASPECT≤6 (OR = 13.208, 95% CI 1.136-153.540) and low hemispheric CSF ratio (OR = 0.966, 95% CI 0.937-0.997) were significantly associated with higher chances for unfavorable functional outcome in patients with LHI. Conclusions: Automated assessment of CSF volume provides an objective biomarker of cerebral edema that can be leveraged to quantify the degree of cerebral edema and confirm its predictive effect on outcomes after LHI.

15.
Bioengineering (Basel) ; 11(3)2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38534506

RESUMEN

Gastric cancer poses a societal and economic burden, prompting an exploration into the development of materials suitable for gastric reconstruction. However, there is a dearth of studies on the mechanical properties of porcine and human stomachs. Therefore, this study was conducted to elucidate their mechanical properties, focusing on interspecies correlations. Stress relaxation and tensile tests assessed the hyperelastic and viscoelastic characteristics of porcine and human stomachs. The thickness, stress-strain curve, elastic modulus, and stress relaxation were assessed. Porcine stomachs were significantly thicker than human stomachs. The stiffness contrast between porcine and human stomachs was evident. Porcine stomachs demonstrated varying elastic modulus values, with the highest in the longitudinal mucosa layer of the corpus and the lowest in the longitudinal intact layer of the fundus. In human stomachs, the elastic modulus of the longitudinal muscular layer of the antrum was the highest, whereas that of the circumferential muscularis layer of the corpus was the lowest. The degree of stress relaxation was higher in human stomachs than in porcine stomachs. This study comprehensively elucidated the differences between porcine and human stomachs attributable to variations across different regions and tissue layers, providing essential biomechanical support for subsequent studies in this field.

16.
J Dent ; 144: 104908, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38432351

RESUMEN

OBJECTIVE: The purpose of this systematic review was to investigate how different interventions can impact the bond strength of additively manufactured crown materials after cementation. DATA/SOURCES: Four online databases Ovid MEDLINE, Scopus, Web of Science and Google Scholar were searched up to January 2023. Inclusion criteria were English-language publications, full-text, and in vitro studies only. Exclusion criteria were studies that did not assess the bonding of an additively manufactured crown material to cement or did not conduct any bond strength tests. An assessment of risk of bias was done in accordance with a modified Consolidated Standards of Reporting Trials (CONSORT) checklist. Each study was analysed and compared based on the interventions and bond strength results. STUDY SELECTION: Six studies satisfied the inclusion and exclusion criteria, five of which evaluated photopolymerised resin and one that tested zirconia manufacturing via 3D printing. All studies observed a low risk of bias. The interventions applied included the type of surface pretreatments, airborne-particle abrasion pressure, cement type, taper of crown, and artificial aging. Three studies compared the bonding performance to milled materials. CONCLUSIONS: The bond strength of crown materials additively manufactured from photopolymers presented high values and are comparable to milled materials. The systematic review demonstrated there was no definite superior cement type, but airborne-particle abrasion with alumina was generally recommended. There is a clear gap in the literature regarding the bond strength of additively manufactured crowns. Therefore, further research is necessary to evaluate its clinical applicability for permanent restorations. CLINICAL SIGNIFICANCE: Factors influencing the bond strength of additively manufactured crown materials should be evaluated so dental professionals can adopt procedures that promote the strongest bond.


Asunto(s)
Coronas , Recubrimiento Dental Adhesivo , Humanos , Materiales Dentales/química , Ensayo de Materiales , Cementos Dentales/química , Circonio/química , Propiedades de Superficie , Cementación/métodos , Impresión Tridimensional , Análisis del Estrés Dental , Técnicas In Vitro
17.
Neuroreport ; 35(7): 431-438, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38526971

RESUMEN

This study aimed to assess the effects of human urinary kallidinogenase (HUK) on motor function outcome and corticospinal tract recovery in patients with acute ischemic stroke (AIS). This study was a randomized, controlled, single-blinded trial. Eighty AIS patients were split into two groups: the HUK and control groups. The HUK group was administered HUK and standard treatment, while the control group received standard treatment only. At admission and discharge, the National Institutes of Health Stroke Scale (NIHSS), Barthel Index (BI) and muscle strength were scored. The primary endpoint was the short-term outcomes of AIS patients under different treatments. The secondary endpoint was the degree of corticospinal tract fiber damage under different treatments. There was a significant improvement in the NIHSS Scale, BI and muscle strength scores in the HUK group compared with controls (Mann-Whitney U test; P  < 0.05). Diffusion tensor tractography classification and intracranial arterial stenosis were independent predictors of short-term recovery by linear regression analysis. The changes in fractional anisotropy (FA) and apparent diffusion coefficient (ADC) decline rate were significantly smaller in the HUK group than in the control group ( P <  0.05). Vascular endothelial growth factor (VEGF) increased significantly after HUK treatment ( P  < 0.05), and the VEGF change was negatively correlated with changes in ADC. HUK is beneficial for the outcome in AIS patients especially in motor function recovery. It may have protective effects on the corticospinal tract which is reflected by the reduction in the FA and ADC decline rates and increased VEGF expression. The study was registered on ClinicalTrials.gov (unique identifier: NCT04102956).


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular Isquémico/complicaciones , Factor A de Crecimiento Endotelial Vascular , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/complicaciones , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/complicaciones , Tractos Piramidales/diagnóstico por imagen , Calicreínas de Tejido
18.
Environ Int ; 186: 108613, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38555663

RESUMEN

Synthetic antioxidants (AOs) are commonly used in everyday items and industrial products to inhibit oxidative deterioration. However, the presence of AOs in food packaging and packaged foods has not been thoroughly documented. Moreover, studies on human exposure to AOs through skin contact with packaging or ingesting packaged foods are limited. In this study, we analyzed twenty-three AOs-including synthetic phenolic antioxidants (SPAs) and organophosphite antioxidants (OPAs)-along with six transformation products in various food samples and their packaging materials. We found AOs in food products at concentrations ranging from 1.30 × 103 to 1.77 × 105 ng/g, which exceeded the levels in both outer packaging (6.05 × 102-3.07 × 104 ng/g) and inner packaging (2.27 × 102-1.09 × 105 ng/g). The most common AOs detected in foodstuffs were tris(2,4-di-tert-butylphenyl) phosphate (AO168O), butylated hydroxytoluene (BHT), and octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (AO1076), together constituting 95.7 % of the total AOs found. Our preliminary exposure assessment revealed that dietary exposure-estimated at a median of 2.55 × 104 ng/kg body weight/day for children and 1.24 × 104 ng/kg body weight/day for adults-is a more significant exposure route than dermal contact with packaging. Notably, four AOs were identified in food for the first time, with BHT making up 76.8 % and 67.6 % of the total BHT intake for children and adults, respectively. These findings suggest that food consumption is a significant source of BHT exposure. The estimated daily intakes of AOs via consumption of foodstuffs were compared with the recommended acceptable daily intake to assess the risks. This systematic investigation into AOs contributes to understanding potential exposure and health risks associated with AOs in packaged foods. It emphasizes the need for further evaluation of human exposure to these substances.


Asunto(s)
Antioxidantes , Embalaje de Alimentos , Humanos , Antioxidantes/análisis , Exposición Dietética/análisis , Dieta , Exposición a Riesgos Ambientales/análisis , Adulto , Contaminación de Alimentos/análisis
19.
Sci Rep ; 14(1): 4406, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38388543

RESUMEN

Shear failure often occurs in engineering rock mass (such as inclined pillar) in gently inclined strata. Prediction and characterization the orientation of shear failure plane is the foundation of rock mass engineering reinforcement. In this paper, sandstone samples are used to perform uniaxial and shear tests to obtain the basic mechanical parameters. Then, by employing the numerical method, the combined compression-shear loading tests were carried out for inclined specimens varied from 0° to 25° at an interval of 5°, to obtain the dip effect on the orientation of rock failure plane. The results show that the failure plane of rock changes with the change of dip angle of rock sample. Based on the Mohr-Coulomb criterion, the ultimate stress state of rock was characterized under combined compression-shear loading. The ultimate strength of rock is equal to the ratio of the stress circle radius of rock under combined compression-shear condition to the stress circle radius of rock under uniaxial compression condition, multiplied by the uniaxial compressive strength. The fracture angle of rock was defined under combined compression-shear loading. A theoretical model was developed for predicting the fracture angle. The developed model could be characterized by internal friction angle, dip angle of rock sample and Poisson's ratio. Finally, the numerical results of the fracture angle were analyzed, which are consistent with the predicted results of the model. The investigation shows that the rock fracture angle has a dip effect, which decreases with the increase of the inclination angle of the sample. The research results provide a new means to identify the potential failure plane of engineering rock mass, and lay a theoretical foundation for calculating the orientation of rock fracture plane.

20.
Hum Resour Health ; 22(1): 15, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38373975

RESUMEN

BACKGROUND: Feminization of health workforce has been globally documented, but it has not been investigated in China. This study aims to analyze changes in the gendered composition of health workforce and explore the trend in different types of health workforce, health organizations and majors within China's health system. METHODS: The data were collected from China Health Statistical Yearbook from 2002 to 2020. We focused on health professionals including doctors, nurses, and pharmacists in health organizations. Trend analysis was employed to examine the change in the ratio of female health workforce over 18 years. The estimated average annual percent change (AAPC) was estimated, and the reciprocals of variances for the female ratios were used as weights. RESULTS: In China, health professionals increased from 4.7 million in 2002 to 10.68 million in 2020. Health professionals per 1000 population increased from 3.41 in 2002 to 7.57 in 2020. The ratio of female health professionals significantly increased from 63.85% in 2002 to 72.4% in 2020 (AAPC = 1.04%, 95% CI 0.96-1.11%, P < 0.001). Female doctors and pharmacists increased 4.7 and 7.9 percentage points from 2002 to 2020. Female health workers at township health centers, village clinics, centers for disease control and prevention had higher annual increase rate (AAPC = 1.67%, 2.25% and 1.33%, respectively) than those at hospital (0.70%) and community health center (0.5%). Female doctors in traditional Chinese medicine, dentistry and public health had higher annual increase rate (AAPC = 1.82%, 1.53% and 1.91%, respectively) than female clinical doctor (0.64%). CONCLUSIONS: More women are participating in the healthcare sector in China. However, socially lower-ranked positions have been feminizing faster, which could be due to the inherent and structural gender norms restricting women's career. More collective and comprehensive system-level actions will be needed to foster a gender-equitable environment for health workforce at all levels.


Asunto(s)
Feminización , Fuerza Laboral en Salud , Masculino , Humanos , Femenino , Recursos Humanos , Personal de Salud , China
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...