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Here, we introduce the magneto-mechanical-genetic (MMG)-driven wireless deep brain stimulation (DBS) using magnetic nanostructures for therapeutic benefits in the mouse model of Parkinson's disease (PD). Electrical DBS of the subthalamic nucleus (STN) is an effective therapy for mitigating Parkinson's motor symptoms. However, its broader application is hampered by the requirement for implanted electrodes and the lack of anatomical and cellular specificity. Using the nanoscale magnetic force actuators (m-Torquer), which deliver torque force under rotating magnetic fields to activate pre-encoded Piezo1 ion channels on target neurons, our system enables wireless and STN-specific DBS without implants, addressing key unmet challenges in the DBS field. In both late- and early-stage PD mice, MMG-DBS significantly improved locomotor activity and motor balance by 2-fold compared to untreated PD mice. Moreover, MMG-DBS enabled sustained therapeutic effects. This approach provides a non-invasive and implant-free DBS with cellular targeting capability for the effective treatment of Parkinsonian symptoms.
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Estimulação Encefálica Profunda , Doença de Parkinson , Transtornos Parkinsonianos , Núcleo Subtalâmico , Camundongos , Animais , Doença de Parkinson/genética , Doença de Parkinson/terapia , Transtornos Parkinsonianos/terapia , Núcleo Subtalâmico/fisiologia , Neurônios/fisiologia , Canais IônicosRESUMO
Graphdiyne (GDY) has garnered significant attention as a cutting-edge 2D material owing to its distinctive electronic, optoelectronic, and mechanical properties, including high mobility, direct bandgap, and remarkable flexibility. One of the key challenges hindering the implementation of this material in flexible applications is its large area and uniform synthesis. The facile growth of centimeter-scale bilayer hydrogen substituted graphdiyne (Bi-HsGDY) on germanium (Ge) substrate is achieved using a low-temperature chemical vapor deposition (CVD) method. This material's field effect transistors (FET) showcase a high carrier mobility of 52.6 cm2 V-1 s-1 and an exceptionally low contact resistance of 10 Ω µm. By transferring the as-grown Bi-HsGDY onto a flexible substrate, a long-distance piezoresistive strain sensor is demonstrated, which exhibits a remarkable gauge factor of 43.34 with a fast response time of ≈275 ms. As a proof of concept, communication by means of Morse code is implemented using a Bi-HsGDY strain sensor. It is believed that these results are anticipated to open new horizons in realizing Bi-HsGDY for innovative flexible device applications.
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BACKGROUND: Obesity is associated with airway hyperresponsiveness and lung fibrosis, which may reduce the effectiveness of standard asthma treatment in individuals suffering from both conditions. Statins and proprotein convertase subtilisin/kexin-9 inhibitors not only reduce serum cholesterol, free fatty acids but also diminish renin-angiotensin system activity and exhibit anti-inflammatory effects. These mechanisms may play a role in mitigating lung pathologies associated with obesity. METHODS: Male C57BL/6 mice were induced to develop obesity through high-fat diet for 16 weeks. Conditional TGF-ß1 transgenic mice were fed a normal diet. These mice were given either atorvastatin or proprotein convertase subtilisin/kexin-9 inhibitor (alirocumab), and the impact on airway hyperresponsiveness and lung pathologies was assessed. RESULTS: High-fat diet-induced obesity enhanced airway hyperresponsiveness, lung fibrosis, macrophages in bronchoalveolar lavage fluid, and pro-inflammatory mediators in the lung. These lipid-lowering agents attenuated airway hyperresponsiveness, macrophages in BALF, lung fibrosis, serum leptin, free fatty acids, TGF-ß1, IL-1ß, IL-6, and IL-17a in the lung. Furthermore, the increased RAS, NLRP3 inflammasome, and cholecystokinin in lung tissue of obese mice were reduced with statin or alirocumab. These agents also suppressed the pro-inflammatory immune responses and lung fibrosis in TGF-ß1 over-expressed transgenic mice with normal diet. CONCLUSIONS: Lipid-lowering treatment has the potential to alleviate obesity-induced airway hyperresponsiveness and lung fibrosis by inhibiting the NLRP3 inflammasome, RAS and cholecystokinin activity.
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Dieta Hiperlipídica , Inibidores de Hidroximetilglutaril-CoA Redutases , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Obesidade , Fibrose Pulmonar , Animais , Masculino , Dieta Hiperlipídica/efeitos adversos , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Camundongos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Fibrose Pulmonar/prevenção & controle , Fibrose Pulmonar/patologia , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/tratamento farmacológico , Inibidores de PCSK9 , Atorvastatina/farmacologia , Atorvastatina/uso terapêutico , Camundongos Obesos , Pró-Proteína Convertase 9/metabolismo , Pró-Proteína Convertase 9/genética , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Hiper-Reatividade Brônquica/prevenção & controle , Hiper-Reatividade Brônquica/tratamento farmacológico , Hiper-Reatividade Brônquica/metabolismo , Hiper-Reatividade Brônquica/fisiopatologia , Anticorpos Monoclonais HumanizadosRESUMO
STATEMENT OF PROBLEM: Scan bodies play a crucial role in the accuracy of digital implant scans by serving as implant-positioning transfer devices. Previous literature has demonstrated the effects of scan body characteristics on the accuracy of digital implant scans. However, the optimal application methods of scan bodies to enhance scanning accuracy remain unclear. PURPOSE: The purpose of this systematic review was to determine the optimal application methods of scan bodies to enhance the accuracy of digital implant scans. MATERIAL AND METHODS: An electronic search was conducted by using the PubMed (MEDLINE), Web of Science, Cochrane Library, and Embase databases from November 2018 to 2023. Relevant references from the included studies were further screened manually for eligibility. Following the population, intervention, comparison, and outcome (PICO) criteria, a research question focused on identifying the optimal application method for effectively using scan bodies to enhance scanning accuracy was developed. Specific inclusion criteria involved in vitro and in vivo studies. The Checklist for Reporting In Vitro Studies (CRIS) guidelines were followed and the assessment of the risk of bias in the included studies was conducted. RESULTS: Sixteen articles that met the eligibility criteria were included in this systematic review. Two studies investigated the effect of scan body bevel orientation on the accuracy of digital implant scans, and 3 examined the impact of tightening torque on scan bodies. Among the studies focusing on completely edentulous arches, 5 recommended the use of auxiliary geometric devices on the dental arch to enhance scanning accuracy. However, 2 studies reported no improvements in accuracy after splinting scan bodies with thread. CONCLUSIONS: Different techniques for applying scan bodies, such as configuring bevel orientation, adjusting tightening torque, and attaching auxiliary geometric devices, influence the accuracy of digital implant scans. For scanning completely edentulous arches, attaching auxiliary devices to scan bodies to cover the edentulous ridge effectively enhances scanning accuracy.
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In this paper, we demonstrate the use of polymer dispersed liquid crystal (PDLC) imprinted with a microlens array (MLA) via solution process to improve the outcoupling efficiency of organic light emitting diodes (OLEDs). The PDLC, well known for its scattering effect, is an excellent technology for improving the outcoupling efficiency of OLEDs. Additionally, we introduce a simple spin-coating process to fabricate PDLC which is adaptable for future solution-processed OLEDs. The MLA-imprinted PDLC applied OLED shows an enhancement factor of 1.22 in outcoupling efficiency which is a 37.5% increase compared to the existing PDLC techniques without changing the electrical properties of the OLED. Through this approach, we can expect the roll-to-roll based extremely flexible OLED, and with further research on pattering PDLC by various templates, higher outcoupling efficiency is achievable through a simple UV irradiation process.
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This study aims to demonstrate that when performing dynamic time warping (DTW) on gait data, multiple optimal warping paths (OWPs) with a minimum sum of local costs can occur and to propose an additional OWP selection method to address this problem. A 3-dimensional motion analysis experiment was conducted on 55 adult participants, including both males and females, to acquire gait data. This study analyzed 990 instances of DTW on gait data to examine the occurrence of multiple OWPs with the minimum sum of local costs. We subsequently applied an additional selection method to the multiple OWPs to determine the feasibility of identifying a single OWP. Multiple OWPs through DTW were observed 82 times, accounting for 8.28%. Notably, on the ankle joint of males, the rate was the highest at 11.11%. Cases with two multiple OWPs were the most prevalent at 56.10%, and cases with ten or more multiple OWPs accounted for 19.51%. The additional selection method proposed in this study was applied to the 82 instances in which multiple OWPs occurred. The results demonstrated the ability to identify a unique OWP in all cases. These results hold significance in identifying the shortcomings of conventional OWP selection methods previously employed and proposing solutions. It enhances the reliability, validity, and accuracy of studies utilizing DTW.
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The craniocervical flexion test (CCFT) is commonly used for assessing the performance and function of the deep cervical flexor muscles; however, objective measurements of cervical segmental motion during craniocervical flexion (CCF) are lacking. Therefore, the purpose of this study aimed to investigate cervical segmental motions during CCFT and determine the relationship between changes of cervical segmental motions and the cervical lordotic angle. A cross-sectional study of prospectively collected data. Twenty healthy participants without neck pain underwent standing cervical radiography (lateral view) to measure the cervical lordotic angle, followed by radiography in supine position during the CCFT. The occipito-atlantal (OA) joint angle, atlantoaxial (AA) joint angle, and cervical spinous process posterior displacement (CSPPD) of the C1-C6 vertebrae were measured using lateral cervical radiographs taken during the initial (20 mm Hg) and low-stage (24 mm Hg) CCFT conditions. The CCF motion during the low-stage CCFT was characterized by a significantly increased OA joint angle, decreased AA joint angle, and increased C1-C6 CSPPD compared with the initial stage (Pâ <â .05). The change in the value of C1-C6 CSPPD at low-stage CCFT showed a significant positive correlation with the cervical lordotic angle. These results indicate that the cervical lordotic angle is important in minimizing CSPPD and performing appropriately-isolated CCF motion during CCFT.
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Atlas Cervical , Pescoço , Humanos , Estudos Transversais , Cervicalgia/diagnóstico por imagem , Vértebras Cervicais/diagnóstico por imagemRESUMO
This case report highlights the management of complications from an open abdomen following surgery for ovarian mucinous adenocarcinoma, a rare subtype of ovarian cancer. A 63-year-old female underwent extensive surgery, including single-port laparoscopic total bilateral salpingo-oophorectomy, right hemicolectomy, small bowel resection, cholecystectomy, and jejunostomy. Postoperatively, she experienced bile leakage, leading to significant skin and fascial damage and an abdominal skin defect. Early detection and multidisciplinary management were crucial. Treatment involved vacuum-assisted closure dressing, repeated debridement, and closure of the open abdomen with a local flap. This case emphasizes the complexities of managing ovarian mucinous adenocarcinoma and the critical role of a multidisciplinary approach in treating postoperative complications, underscoring the importance of vigilant postoperative care and timely intervention.
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We report the first observation of spectral blue shift of plasmon resonance of synthesized silver nanoparticles (AgNPs) due to a negative optical nonlinearity of a local ambient medium, i.e., indigo carmine (IC) solution at around 420 nm wavelength. The blue shift occurred at a larger concentration of AgNPs or at a larger concentration of IC solution, being in obvious contrast to spectral red shift which was widely witnessed in plasmon spectral shift in a linear regime. Plasmon-enhanced local fields could excite the third-order optical nonlinearity for blue shift even under continuous (non-pulsed) light illumination. We also found that the plasmon-excited nonlinearity could allow for differential nonlinear response of the IC solution to be even greater than its differential linear response, though appearing to be somewhat inconsistent with what was generally known in light-matter interaction. The demonstrated properties of such anomalous shift of plasmon spectral peaks and its accompanying properties indicated that plasmon technologies could be exploited not only in linear but also in nonlinear aspects for critical optimization in plasmon-energy harvesting systems such as in surface enhanced spectroscopy/microscopy, biomedical imaging/sensing, laser frequency conversion, ultrashort pulse generation, and all-optical switching.
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PURPOSE: To evaluate the wear resistance of a printed interim resin manufactured with different printing and postpolymerization parameters. MATERIALS AND METHODS: Overall, 130 rectangular resin specimens (15 × 10 × 10 mm) were 3D-printed. Among the specimens, 60 were printed with different printing orientations (0, 45, and 90 degrees) and layer thicknesses (50 and 100 µm) to create six groups to investigate the effects of the printing parameters (n = 10 per group). The remaining 70 specimens were used to evaluate the effects of postpolymerization; for this, seven groups were created as follows (n = 10 per group): nonpostpolymerized; postpolymerized for 5, 15, and 30 minutes with an ultraviolet light-emitting diode (LED) device; and postpolymerized for 5, 15, and 30 minutes with an ultraviolet light bulb device. After masticatory simulation, the wear volume loss was calculated with 3D metrology software. One-way and two-way ANOVA were used for intergroup comparisons (α = .05). RESULTS: The group printed with a build angle of 45 degrees showed lower wear volume loss than the 0- and 90-degree groups (P < .01). The wear volume loss in the ultraviolet LED group was significantly greater than that in the ultraviolet light bulb group (P = .04). No significant difference was observed in the wear volume loss of the printed resin with respect to the layer thickness and polymerization time (P > .05). However, the non-postpolymerized group showed significantly greater wear volume loss than the other groups (P < .001). CONCLUSIONS: The printed resin showed greater wear resistance when it was printed at a build angle of 45 degrees and postpolymerized with an ultraviolet light bulb device.
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Impressão Tridimensional , Software , Teste de Materiais , Simulação por ComputadorRESUMO
We aimed to determine the association between changes in bone mineral density (BMD) of the lumbar spine, bilateral femoral necks and clinical parameters in ambulatory older adult patients with stroke who were diagnosed with osteopenia. This retrospective study included ambulatory patients older than 65 years diagnosed with stroke between January 2019 and June 2021. Osteopenia was diagnosed within 1 month after stroke diagnosis. Subsequently, follow-up BMD was performed within 12 to 14 months. The manual muscle test and modified Barthel index were measured as clinical parameters, and bone turnover markers were measured as biochemical markers. The Wilcoxon signed-rank test was used to compare whether a significant difference in the change in BMD was noted at each site measured at 1-year intervals. The BMD of the paretic and non-paretic femoral necks decreased significantly over time, but no significant change was observed in the BMD of the lumbar spine. Bone turnover markers were significantly changed at follow-up. Patients with modified Barthel index of less than 82 had significant bone loss only on the paretic side of the femoral neck. The BMD of the paretic side of the femoral neck was significantly decreased regardless of the strength of the hip and knee extensors. Although older adult patients with stroke and osteopenia can walk independently, more active osteoporosis treatment is needed to prevent bone loss and fractures, including improvement in daily living function and bilateral lower extremity strength training.
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Doenças Ósseas Metabólicas , Osteoporose , Acidente Vascular Cerebral , Humanos , Idoso , Densidade Óssea , Estudos Retrospectivos , Osteoporose/etiologia , Doenças Ósseas Metabólicas/etiologia , Acidente Vascular Cerebral/complicações , Vértebras Lombares/diagnóstico por imagemRESUMO
Urinary tract infections (UTI) are common in patients with stroke. The colonization of multidrug-resistant organisms (MDR) has recently become a global issue, and infection with MDR is associated with a poorer prognosis. This study aimed to investigate the uropathogenic distribution in stroke patients according to MDR colonization and investigate the infection risk and antibiotic resistance of each uropathogen to help determine initial antibiotic treatment. This study is a retrospective study conducted on patients who underwent inpatient treatment for stroke at Kosin University Gospel Hospital in 2019 to 2021. The participants were classified into Group VRE if vancomycin-resistant Enterococcus (VRE) colonization was confirmed, Group CRE if carbapenem-resistant Enterobacteriaceae (CRE) colonization was confirmed, and Group Negative if no MDR colonization was confirmed. Urine culture was performed if symptomatic UTI was suspected. Uropathogenic distribution, antibiotic resistance patterns were assessed by one-way analysis of variance, independent t-test, and Pearson chi-square test. And the infection risk factors for each uropathogen were assessed by multinomial logistic regression analysis. Six hundred thirty-three participants were enrolled. The mean age of all participants was 69.77â ±â 14.91, with 305 males and 328 females, including 344 hemorrhagic strokes and 289 ischemic strokes. No growth in urine culture was the most common finding (nâ =â 281), followed by Escherichia coli (E.coli) (nâ =â 141), and Enterococcus spp. (nâ =â 80). Group Negative had significantly more cases of no growth in urine culture than Group VRE (Odds ratio [OR], 11.698; 95% confidence interval [CI], 3.566-38.375; Pâ <â .001) and than Group CRE (OR, 11.381; 95% CI, 2.665-48.611; Pâ <â .001). Group VRE had significantly more E.coli (OR, 2.905; 95% CI, 1.505-5.618; Pâ =â .001), and more Enterococcus (OR, 4.550; 95% CI, 2.253-9.187; Pâ <â .001) than Group Negative. There was no statistical difference in antibiotic resistance according to MDR colonization in E coli, but for Enterococcus spp., Group VRE and CRE showed significantly more resistance to numerous antibiotics than Group Negative. MDR colonization increases the risk of UTI and is associated with greater antibiotic resistance. For appropriate administration of antibiotics in UTI, continuous monitoring of the latest trends in uropathogenic distribution is required, and clinicians should pay more attention to the use of initial empirical antibiotics in patients with MDR colonization.
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Enterobacteriáceas Resistentes a Carbapenêmicos , Acidente Vascular Cerebral , Enterococos Resistentes à Vancomicina , Masculino , Feminino , Humanos , Farmacorresistência Bacteriana Múltipla , Estudos Retrospectivos , Escherichia coli , Antibacterianos/uso terapêutico , Antibacterianos/farmacologia , Acidente Vascular Cerebral/tratamento farmacológicoRESUMO
Background: Few studies have evaluated the comparative efficacy of biologics for asthma. This network meta-analysis aimed to compare the efficacy of biologics. Methods: This study included randomized controlled trials (RCTs) evaluating the efficacy of a biologic compared to a placebo or another biologic in patients with inadequately controlled asthma despite high-intensity treatment, published by January 6, 2022. Two researchers independently searched the PubMed, Embase, Web of Science, and Scopus and assessed the risk of bias using the Cochrane tool. The outcomes of interest were the annual asthma exacerbation rate (AER), forced expiratory volume per second before bronchodilator use (preBD FEV1), the asthma control questionnaire (ACQ), and asthma quality of life questionnaire (AQLQ) results. A frequentist network meta-analysis was conducted, and a random effects model was used to draw pooled incidence rate ratio or standardized mean differences. Results: Twenty-three RCTs with 8376 participants were retrieved. All biologics included in this study were associated with significantly better effects than placebo in AER, preBD FEV1, and ACQ outcomes. Although there were no significant differences between the biologics in the overall study population, patients with eosinophil levels ≥300 cells/µL or eosinophilic asthma showed that dupilumab and tezepelumab were significantly better than anti-IL-5 biologics in improving preBD FEV1. Additionally, in patients with eosinophil levels ≥300 cells/µL, benralizumab, unlike reslizumab, performed significantly better than placebo in improving ACQ and AQLQ outcomes. Conclusion: The comparative effects of biologics can be considered with phenotypes and biomarkers to help clinicians select an appropriate treatment for inadequately controlled asthma.
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This study aimed to investigate the effects of sandblasting on the physical properties and bond strength of two types of translucent zirconia: niobium-oxide-containing yttria-stabilized tetragonal zirconia polycrystals ((Y, Nb)-TZP) and 5 mol% yttria-partially stabilized zirconia (5Y-PSZ). Fully sintered disc specimens were either sandblasted with 125 µm alumina particles or left as-sintered. Surface roughness, crystal phase compositions, and surface morphology were explored. Biaxial flexural strength (n=10) and shear bond strength (SBS) (n=12) were evaluated, including thermocycling conditions. Results indicated a decrease in flexural strength of 5Y-PSZ from 601 to 303 MPa upon sandblasting, while (Y, Nb)-TZP improved from 458 to 544 MPa. Both materials significantly increased SBS after sandblasting (p<0.001). After thermocycling, (Y, Nb)-TZP maintained superior SBS (14.3 MPa) compared to 5Y-PSZ (11.3 MPa) (p<0.001). The study concludes that (Y, Nb)-TZP is preferable for sandblasting applications, particularly for achieving durable bonding without compromising flexural strength.
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Materiais Dentários , Nióbio , Óxidos , Materiais Dentários/química , Teste de Materiais , Propriedades de Superfície , Zircônio/química , Ítrio/química , Óxido de Alumínio , Resistência ao CisalhamentoRESUMO
Breast cancer-related lymphedema (BCRL) occurs usually on the affected side, and its cause and pathophysiology are well known. However, the cause of edema of the upper extremity on the unaffected side is barely known. It is often considered to be chemotherapy-induced general edema, and clinical evaluation is rarely performed in these patients. This study aimed to present the clinical characteristics of unilateral breast cancer patients with edema of upper extremity on the unaffected side, and to emphasize the importance of early diagnosis and medical interventions. This study retrospectively analyzed the medical records of unilateral breast cancer patients complaining edema of upper extremity on the unaffected side, from January 2020 to May 2021. Lymphoscintigraphy was used to assist in confirming the diagnosis of lymphedema, and Doppler ultrasonography or 3D computed tomography angiography were performed to differentiate vascular problems. Fourteen patients were enrolled in the study. Seven, 3, and 4 patients had edema of both upper extremities, edema of the upper extremity on the unaffected side only, and edema of all extremities, respectively. None of the 4 patients with edema of all extremities showed abnormal findings on examination. In patients with edema in the upper extremity on the unaffected side alone, lymphatic flow dysfunction was seen in 2 patients, and deep vein thrombosis (DVT) was diagnosed in 1. In patients with edema of both upper extremities, lymphatic flow dysfunction was seen in 2 patients, and DVT was diagnosed in 3. One patient had DVT and accompanying lymphatic flow dysfunction. Lymphedema and DVT were diagnosed in a number of patients with edema of the upper extremity on the unaffected side, and lymphedema can occur without direct injury to the lymphatic flow system. Therefore, clinicians should not overlook the fact that diseases that require early diagnosis and treatment can occur in patients with edema of the unaffected upper extremity.
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Neoplasias da Mama , Extremidade Superior , Humanos , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Extremidade Superior/fisiopatologia , Neoplasias da Mama/complicações , Adulto , Idoso , Linfedema/etiologia , Linfedema/diagnóstico , Edema/etiologia , Linfocintigrafia/métodos , Ultrassonografia Doppler/métodos , Linfedema Relacionado a Câncer de Mama/diagnóstico , Angiografia por Tomografia Computadorizada/métodosRESUMO
PURPOSE: Following the withdrawal of propacetamol in Europe owing to safety issues, the regulatory authority of South Korea requested a post-marketing surveillance study to investigate its safety profile. MATERIALS AND METHODS: We conducted nested case-control and case-time-control (CTC) analyses of cases and controls identified for outcomes of interest, including anaphylaxis, thrombosis, and Stevens-Johnson syndrome (SJS), using the claims database of South Korea, 2010-2019. Risk-set sampling was used to match each case with up to 10 controls for age, sex, cohort entry date, and follow-up duration. Exposure to anaphylaxis, thrombosis, and SJS was assessed within 7, 90, and 30 days of the index date, respectively. We calculated odds ratios (OR) with 95% confidence intervals (CIs) using conditional logistic regression to assess the risk of outcomes associated with propacetamol. RESULTS: We identified cases of anaphylaxis (n=61), thrombosis (n=95), and SJS (n=1) and matched them to controls (173, 268, and 4, respectively). In the nested case-control analysis, the ORs for anaphylaxis and SJS were inestimable given the small number of propacetamol users during the risk period; meanwhile, the OR for thrombosis was 1.60 (95% CI 0.71-3.62). In the CTC design, the effect estimate was only estimated for thrombosis (OR 0.56, 95% CI 0.09-3.47). CONCLUSION: In both nested case-control and CTC analyses, propacetamol was not associated with an increased risk of anaphylaxis, thrombosis, or SJS. The findings from this study, which used routinely collected clinical data, provide reassuring real-world evidence regarding the safety of propacetamol in a nationwide population to support regulatory decision-making.
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Anafilaxia , Síndrome de Stevens-Johnson , Trombose , Humanos , Anafilaxia/induzido quimicamente , Anafilaxia/epidemiologia , Estudos de Casos e Controles , Acetaminofen/efeitos adversos , Síndrome de Stevens-Johnson/etiologia , Trombose/complicaçõesRESUMO
OBJECTIVES: Natural teeth and dental restorations present with various shades and levels of translucency. This study aimed to determine whether these variations in ceramic crowns and scan powder application affect the trueness of intraoral scanners. METHODS: Eight identical premade resin typodonts, each prepared for a crown on the maxillary right second molar, were used. Eight lithium disilicate crowns, distinguished by two levels of translucency (high and low) and four shades (BL1, A2, A3, and A4), were fabricated to an identical design and cemented onto each typodont, providing eight distinct experimental groups (2 levels of translucency × 4 shades). Reference scans were acquired using a desktop scanner. Test scans were performed ten times for each experimental group using two different intraoral scanners (Medit i700 and CEREC Primescan AC), with and without the application of scan powder (n = 10). Three-dimensional metrology software was used to assess the trueness of the intraoral scan datasets. Statistical analysis involved the Kruskal-Wallis H test, Mann-Whitney U test, and independent t-test (α=0.05). RESULTS: For powder-free intraoral scan datasets, the crown shade did not significantly affect trueness within each translucency group (P = 1.000). For both intraoral scanners, compared with low translucency groups, higher marked deviations were exhibited by high translucency groups (P<.001). Scan powder use largely mitigated these differences (P>.05) and enhanced the trueness of the intraoral scan (P<.01). CONCLUSIONS: Shade did not significantly influence the trueness of intraoral scans. High-translucency crowns were scanned with less accuracy than were low-translucency crowns. CLINICAL SIGNIFICANCE: Unlike tooth shade, translucency significantly affected the accuracy of intraoral scans. Therefore, considering the use of scan powder when scanning objects with high translucency may be beneficial.
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Desenho Assistido por Computador , Coroas , Porcelana Dentária , Planejamento de Prótese Dentária , Pós , Humanos , Porcelana Dentária/química , Cor , Pigmentação em Prótese , Imageamento Tridimensional/métodos , Cerâmica , Dente Molar/diagnóstico por imagem , Dente Molar/anatomia & histologia , Processamento de Imagem Assistida por Computador/métodosRESUMO
Semi-infinite single-atom-thick graphene is an ideal reinforcing material that can simultaneously improve the mechanical, electrical, and thermal properties of matrix. Here, we present a float-stacking strategy to accurately align the monolayer graphene reinforcement in polymer matrix. We float graphene-poly(methylmethacrylate) (PMMA) membrane (GPM) at the water-air interface, and wind-up layer-by-layer by roller. During the stacking process, the inherent water meniscus continuously induces web tension of the GPM, suppressing wrinkle and folding generation. Moreover, rolling-up and hot-rolling mill process above the glass transition temperature of PMMA induces conformal contact between each layer. This allows for pre-tension of the composite, maximizing its reinforcing efficiency. The number and spacing of the embedded graphene fillers are precisely controlled. Notably, we accurately align 100 layers of monolayer graphene in a PMMA matrix with the same intervals to achieve a specific strength of about 118.5 MPa g-1 cm3, which is higher than that of lightweight Al alloy, and a thermal conductivity of about 4.00 W m-1 K-1, which is increased by about 2,000 %, compared to the PMMA film.
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Flexible intracortical neural probes have drawn attention for their enhanced longevity in high-resolution neural recordings due to reduced tissue reaction. However, the conventional monolithic fabrication approach has met significant challenges in: (i) scaling the number of recording sites for electrophysiology; (ii) integrating of other physiological sensing and modulation; and (iii) configuring into three-dimensional (3D) shapes for multi-sided electrode arrays. We report an innovative self-assembly technology that allows for implementing flexible origami neural probes as an effective alternative to overcome these challenges. By using magnetic-field-assisted hybrid self-assembly, multiple probes with various modalities can be stacked on top of each other with precise alignment. Using this approach, we demonstrated a multifunctional device with scalable high-density recording sites, dopamine sensors and a temperature sensor integrated on a single flexible probe. Simultaneous large-scale, high-spatial-resolution electrophysiology was demonstrated along with local temperature sensing and dopamine concentration monitoring. A high-density 3D origami probe was assembled by wrapping planar probes around a thin fiber in a diameter of 80â¼105 µm using optimal foldable design and capillary force. Directional optogenetic modulation could be achieved with illumination from the neuron-sized micro-LEDs (µLEDs) integrated on the surface of 3D origami probes. We could identify angular heterogeneous single-unit signals and neural connectivity 360° surrounding the probe. The probe longevity was validated by chronic recordings of 64-channel stacked probes in behaving mice for up to 140 days. With the modular, customizable assembly technologies presented, we demonstrated a novel and highly flexible solution to accommodate multifunctional integration, channel scaling, and 3D array configuration.
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Machines found in nature and human-made machines share common components, such as an engine, and an output element, such as a rotor, linked by a clutch. This clutch, as seen in biological structures such as dynein, myosin or bacterial flagellar motors, allows for temporary disengagement of the moving parts from the running engine. However, such sophistication is still challenging to achieve in artificial nanomachines. Here we present a spherical rotary nanomotor with a reversible clutch system based on precise molecular recognition of built-in DNA strands. The clutch couples and decouples the engine from the machine's rotor in response to encoded inputs such as DNA or RNA. The nanomotor comprises a porous nanocage as a spherical rotor to confine the magnetic engine particle within the nanospace (â¼0.004 µm3) of the cage. Thus, the entropically driven irreversible disintegration of the magnetic engine and the spherical rotor during the disengagement process is eliminated, and an exchange of microenvironmental inputs is possible through the nanopores. Our motor is only 200 nm in size and the clutch-mediated force transmission powered by an embedded ferromagnetic nanocrystal is high enough (â¼15.5 pN at 50 mT) for the in vitro mechanical activation of Notch and integrin receptors, demonstrating its potential as nano-bio machinery.