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1.
Bioact Mater ; 38: 181-194, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38711758

RESUMEN

Chronic diabetic wounds are the most common complication for diabetic patients. Due to high oxidative stress levels affecting the entire healing process, treating diabetic wounds remains a challenge. Here, we present a strategy for continuously regulating oxidative stress microenvironment by the catalyst-like magnesium-gallate metal-organic framework (Mg-GA MOF) and developing sprayable hydrogel dressing with sodium alginate/chitosan quaternary ammonium salts to treat diabetic wounds. Chitosan quaternary ammonium salts with antibacterial properties can prevent bacterial infection. The continuous release of gallic acid (GA) effectively eliminates reactive oxygen species (ROS), reduces oxidative stress, and accelerates the polarization of M1-type macrophages to M2-type, shortening the transition between inflammation and proliferative phase and maintaining redox balance. Besides, magnesium ions adjuvant therapy promotes vascular regeneration and neuronal formation by activating the expression of vascular-associated genes. Sprayable hydrogel dressings with antibacterial, antioxidant, and inflammatory regulation rapidly repair diabetic wounds by promoting neurovascular network reconstruction and accelerating re-epithelialization and collagen deposition. This study confirms the feasibility of catalyst-like MOF-contained sprayable hydrogel to regulate the microenvironment continuously and provides guidance for developing the next generation of non-drug diabetes dressings.

2.
3.
J Clin Med ; 13(10)2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38792475

RESUMEN

Background: The development of temporal bone pneumatization is related to the postnatal middle ear environment, where the development of air cells is suppressed with otitis media in early childhood. However, whether air cell formation restarts when mastoidectomy is performed during temporal bone pneumatization remains unclear. Herein, we evaluated temporal bone pneumatization after canal wall up (CWU) tympanomastoidectomy for middle ear cholesteatoma in children. Methods: In total, 63 patients, including 29 patients with congenital cholesteatoma (CC) and 34 patients with acquired cholesteatoma (AC), were assessed using a set of pre- and postoperative computed tomography images. The air cells of the temporal bone were divided into five areas: periantral (anterior), periantral (posterior), periantral (medial), peritubal, and petrous apex. The number of areas with air cells before and after surgery was compared to evaluate temporal bone pneumatization after surgery. Results: A total of 63 patients, comprising 29 with CC and 34 with AC (pars flaccida; 23, pars tensa; 7, unclassified; 4), were evaluated. The median age of patients (18 males and 11 females) with CC was 5.0 (range, 2-15 years), while that of the AC group (23 males and 11 females) was 8 (range, 2-15 years). A significant difference in air cell presence was identified in the CC and AC groups after surgery (Mann-Whitney U, p < 0.001 and p = 0.003, respectively). Between the two groups, considerably better postoperative pneumatization was observed in the CC group. A correlation between age at surgery and gain of postoperative air cell area development was identified in the CC group (Spearman's rank-order correlation coefficient, r = -0.584, p < 0.001). In comparison with the postoperative pneumatization rate of each classified area, the petrous apex area was the lowest in the CC and AC groups. Conclusions: Newly developed air cells were identified in the temporal bones after CWU mastoidectomy for pediatric cholesteatoma. These findings may justify CWU tympanomastoidectomy, at least for younger children and CC patients, who may subsequently develop air cell systems after surgery.

4.
Thyroid Res ; 17(1): 9, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38705974

RESUMEN

BACKGROUND: Hyalinizing trabecular tumor (HTT) is an uncommon follicular cell-derived thyroid tumor classified as a low-risk neoplasm by the World Health Organization Classification of Tumors of Endocrine Organs, 5th edition. The PAX8-GLIS3 gene fusion is reportedly a pathognomonic genetic alteration of HTT. CASE PRESENTATION: A 43-year-old Japanese female was incidentally discovered to have an 8-mm, well-defined, hypoechoic mass in the left lobe of the thyroid gland by ultrasound examination. Contrast-enhanced computed tomography scan revealed a solid mass exhibiting slight homogeneous enhancement in the lower pole of the thyroid gland. The mass was diagnosed as atypia of undetermined significance by fine-needle aspiration cytology. The patient underwent left hemithyroidectomy with routine central compartment dissection. Histologic findings revealed tumor cells with elongated nuclei and intranuclear pseudoinclusions arranged with trabeculae architecture or small nests in hyalinized stroma. Weak membranous and cytoplasmic staining was found by MIB1 (Ki-67) immunostaining. The final diagnosis was HTT of the thyroid gland. Next-generation sequencing genetic analysis of a surgical specimen revealed no pathologic mutations, including BRAF, H/K/NRAS, or RET-PTC fusions. The PAX8-GLIS3 fusion was detected by RT-PCR. CONCLUSIONS: A rare case of HTT was demonstrated through imaging, cytologic, histologic and molecular investigations. PAX8-GLIS3 fusion detected by RT-PCR and Sanger sequencing was confirmed to be a genetic hallmark of HTT.

5.
J Med Virol ; 96(3): e29432, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38509793

RESUMEN

BACKGROUND AND AIMS: Mortality after sustained virological response (SVR) with interferon-free direct-acting antiviral (IFN-free DAA) therapy is crucial for optimizing post-SVR patient care, but it remains unclear, especially regarding non-liver-related mortality. METHODS: Consecutive post-SVR patients from 14 institutions were stratified into three cohorts: A (without advanced fibrosis and without prior HCC), B (with advanced fibrosis and without prior HCC), and C (curative HCC treatment). We assessed mortality (per 1000 person-years [/1000PY]) post-SVR. Mortality rates were compared between cohorts A and B and the general population using age- and sex-adjusted standardized mortality ratio (SMR). Comparison of survival between each cohort was performed using propensity-score (PS) matching with sex, age, and comorbidity. RESULTS: In cohort A (n = 762; median age, 65 years), 22 patients died (median follow-up, 36 months); all-cause mortality was 10.0/1000PY, with 86.4% non-liver-related deaths. In cohort B (n = 519; median age, 73 years), 27 patients died (median follow-up, 39 months); all-cause mortality was 16.7/1000PY, with 88.9% non-liver-related deaths. In both cohorts, malignant neoplasm was the most common cause of death; all-cause mortality was comparable to that of the general population (SMR: 0.96 and 0.92). In cohort C (n = 108; median age, 75 years), 15 patients died (median follow-up, 51 months); all-cause mortality was 36.0/1000PY, with 53.3% liver-related deaths. PS matching showed no significant survival differences between cohorts A and B, both of which had better survival than cohort C. CONCLUSIONS: Mortality varies based on HCC history in the DAA era; nevertheless, attention should be paid to non-liver-related deaths in all post-SVR patients.


Asunto(s)
Carcinoma Hepatocelular , Hepatitis C Crónica , Neoplasias Hepáticas , Humanos , Anciano , Antivirales/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/etiología , Hepatitis C Crónica/tratamiento farmacológico , Respuesta Virológica Sostenida , Fibrosis
6.
Ear Nose Throat J ; : 1455613241231146, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38369960

RESUMEN

A 71-year-old man with neurofibromatosis type 1 (NF1) presented to our department with a 1-week history of a painful mass in the left submandibular area. Computed tomography (CT) and magnetic resonance imaging revealed an irregular-shaped tumor with a diameter of 2.0 cm in the left submandibular gland and a metastatic lymph node with a diameter of 1.0 cm adjacent to the tumor. Fluorodeoxyglucose-positron emission tomography/CT revealed increased uptake in the tumor. Fine-needle aspiration cytology revealed atypical cells, suggesting salivary duct carcinoma (SDC). Left neck dissection with resection of the tumor and submandibular gland was performed under general anesthesia. Histologic examination revealed ductal formation with a solid, cystic, cribriform, and papillary structure with intraductal comedonecrosis, diagnosing as SDC originating in the submandibular gland (pT3N1M0 pStage III). Mutational analysis of 160 cancer-related genes by next-generation sequencing (NGS) revealed a germline and frameshift mutation in the NF1 gene (p.R2408Kfs*14) and a somatic and frameshift mutation in the TP53 gene (p.C176Wfs*22). The patient received postoperative radiotherapy to the left neck area at 66 Gy. No evidence of recurrence or metastasis has been observed as of 10 months postoperatively. This is the first reported case of SDC in the submandibular gland in a patient with NF1. The mutational data by NGS may contribute to a better understanding of the oncogenesis of SDC in patients with NF1.

7.
Biomacromolecules ; 25(3): 1509-1526, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38376392

RESUMEN

The multifaceted process of nerve regeneration following damage remains a significant clinical issue, due to the lack of a favorable regenerative microenvironment and insufficient endogenous biochemical signaling. However, the current nerve grafts have limitations in functionality, as they require a greater capacity to effectively regulate the intricate microenvironment associated with nerve regeneration. In this regard, we proposed the construction of a functional artificial scaffold based on a "two-pronged" approach. The whole system was developed by encapsulating Tazarotene within nanomicelles formed through self-assembly of reactive oxygen species (ROS)-responsive amphiphilic triblock copolymer, all of which were further loaded into a thermosensitive injectable hydrogel. Notably, the hydrogel exhibits obvious temperature sensitivity at a concentration of 6 wt %, and the nanoparticles possess concentration-dependent H2O2-response capability with a controlled release profile in 48 h. The combined strategy promoted the repair of injured peripheral nerves, attributed to the dual role of the materials, which mainly involved providing structural support, modulating the immune microenvironment, and enhancing angiogenesis. Overall, this study opens up intriguing prospects in tissue engineering.


Asunto(s)
Sistemas de Liberación de Medicamentos , Peróxido de Hidrógeno , Peróxido de Hidrógeno/farmacología , Ingeniería de Tejidos , Hidrogeles/farmacología , Hidrogeles/química , Nervios Periféricos/fisiología , Regeneración Nerviosa
8.
J Rural Med ; 19(1): 44-48, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38196806

RESUMEN

Objective: Bile duct tumor thrombosis in hepatocellular carcinoma (HCC) is a relatively rare event with a poor prognosis. Furthermore, bile duct tumor thrombus in HCC may be misdiagnosed when only imaging modalities are used. The efficiency of peroral cholangioscopy (POCS) in evaluating bile duct lesions has been reported. Patients: We present three cases of HCC with bile duct strictures in which POCS was performed as a preoperative evaluation. Results: In these three cases, diagnosing whether the lesion was a bile duct tumor thrombus on CT and endoscopic retrograde cholangiopancreatography was difficult. We performed POCS in three cases and were able to diagnose the presence of bile duct tumor thrombus of HCC, including differentiation from extrinsic compression of the bile duct. Conclusion: POCS for HCC with bile duct features is useful for the preoperative diagnosis of bile duct tumor thrombus, especially in cases where the surgical procedure depends on the presence of bile duct tumor thrombus.

9.
Asian J Surg ; 47(1): 413-419, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37752023

RESUMEN

BACKGROUND: The aim of this study was to evaluate the correlation among mutations in cancer-related genes, clinicopathologic features, and clinical outcome in classical papillary thyroid carcinoma (PTC). PATIENTS AND METHODS: A total of 130 patients with classical PTC who underwent curative surgery between April 2012 and June 2023 at Hokuto Hospital were included. Mutations in targeted regions of 160 cancer-related genes were detected by next-generation sequencing (NGS)-based cancer panel testing. RESULTS: The BRAF V600E mutation was detected in 108 (83.1%) of 130 PTC patients. Among the 108 patients with the BRAF V600E mutation, other co-existing oncogenic mutations were found in 12 (9.2%) patients. When we divided into 3 groups of no mutations, BRAF V600E mutation alone, and BRAF V600E and other oncogenic mutations, significant differences were observed in terms of tracheal invasion (P = 0.0024), and bilateral neck lymph node metastasis (P = 0.0047). Kaplan-Meier analysis of overall survival (OS) revealed patients with BRAF V600E and other oncogenic mutations had significantly poorer survival than those with BRAF V600E mutation alone (P = 0.0026). Multivariate cox proportional hazard analysis revealed BRAF V600E and other oncogenic mutations was an independent prognostic factor for OS (HR: 10.559; 95%CI: 1.007-110.656, P = 0.0493). CONCLUSIONS: The BRAF V600E mutation co-existing with other oncogenic mutations but not the BRAF V600E mutation alone was associated with aggressive clinicopathologic features, resulting in poor prognosis in patients with classical PTC. Detection of oncogenic mutations using NGS-based cancer panel testing could enhance understanding of the clinical features of classical PTC.


Asunto(s)
Carcinoma Papilar , Neoplasias de la Tiroides , Humanos , Cáncer Papilar Tiroideo/genética , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/cirugía , Proteínas Proto-Oncogénicas B-raf/genética , Carcinoma Papilar/genética , Carcinoma Papilar/cirugía , Carcinoma Papilar/patología , Mutación , Pronóstico
10.
Chem Pharm Bull (Tokyo) ; 72(1): 36-40, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37899177

RESUMEN

The spectrum of 31P-NMR is fundamentally simpler than that of 1H-NMR; consequently identifying the target signal(s) for quantitation is simpler using quantitative 31P-NMR (31P-qNMR) than using quantitative 1H-NMR (1H-qNMR), which has been already established as an absolute determination method. We have previously reported a 31P-qNMR method for the absolute determination of cyclophosphamide hydrate and sofosbuvir as water-soluble and water-insoluble organophosphorus compounds, respectively. This study introduces the purity determination of brigatinib (BR), an organophosphorus compound with limited water solubility, using 31P-qNMR at multiple laboratories. Phosphonoacetic acid (PAA) and 1,4-BTMSB-d4 were selected as the reference standards (RSs) for 31P-qNMR and 1H-qNMR, respectively. The qNMR solvents were chosen based on the solubilities of BR and the RSs for qNMR. CD3OH was selected as the solvent for 31P-qNMR measurements to prevent the influence of deuterium exchange caused by the presence of exchangeable intramolecular protons of BR and PAA on the quantitative values, while CD3OD was the solvent of choice for the 1H-qNMR measurements to prevent the influence of water signals and the exchangeable intramolecular protons of BR and PAA. The mean purity of BR determined by 31P-qNMR was 97.94 ± 0.69%, which was in agreement with that determined by 1H-qNMR (97.26 ± 0.71%), thus indicating the feasibility of purity determination of BR by 31P-qNMR. Therefore, the findings of this study may provide an effective method that is simpler than conventional 1H-qNMR for the determination of organophosphorus compounds.


Asunto(s)
Compuestos Organofosforados , Protones , Estándares de Referencia , Agua , Solventes
11.
J Mater Chem B ; 11(39): 9532-9544, 2023 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-37750817

RESUMEN

Repairing infected bone defects remains a severe challenge due to antibiotic abuse and recurrence. Hence, we modified magnetocaloric Fe3O4 nanoparticles and added them to magnesium calcium phosphate bone cement (MCPC) to fabricate multifunctional magnetic composites for sequential bacterial inhibition, angiogenesis and osteogenesis. Nevertheless, high doses of Mg ions and Fe ions were released from MCPC, which adversely affected osteogenesis. Thus, Fe3O4 was modified using gelatin according to the emulsification crosslinking method, which exhibited a controllable magnetocaloric effect and degradation behavior, and favorable anti-bacterial ability under the action of an alternating magnetic field (AMF). In the early stage, the residual MgO created a local strong alkaline microenvironment by hydrolysis, which inhibited the function and activity of S. aureus and E. coli. At the later stage, the MCPC composites were controllably degraded under the function of gelatin and maintained a long-term local slight alkaline microenvironment that promoted the osteogenic differentiation and mineralization of BMSCs. In vivo subcutaneous implantation experiments further indicated that MCPC composites showed good biocompatibility and facilitated angiogenesis, presenting a promising future in magnetic materials design and infectious bone defect repair.


Asunto(s)
Cementos para Huesos , Osteogénesis , Cementos para Huesos/farmacología , Gelatina/farmacología , Staphylococcus aureus , Escherichia coli , Fosfatos/farmacología
12.
Artículo en Inglés | MEDLINE | ID: mdl-37458570

RESUMEN

Summary: There are very few reports of syndrome of inappropriate antidiuresis hormone secretion (SIADH) after receiving severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccine. Herein, we present the case of an 84-year-old woman who developed severe hyponatremia following the second administration of the SARS-CoV-2 mRNA vaccine. The patient presented with nausea, vomiting, and headache. Laboratory tests showed a plasma sodium level of 119 mmol/L. After receiving 500 mL of intravenous saline over a 2-h period, her plasma sodium level raised to 121 mmol/L, but her symptoms persisted. Considering that rapid plasma sodium correction was necessary, we started 3% saline solution overnight. Her plasma sodium level raised to 132 mmol/L and her symptoms completely resolved. Clinical and laboratory findings were consistent with a diagnosis of SIADH. In the absence of any other triggering factors, we concluded that the condition was likely associated with the vaccination. Clinicians should be aware of the potential for hyponatremia, particularly SIADH, associated with SARS-CoV-2 mRNA vaccination. Learning points: Reports of syndrome of inappropriate antidiuresis hormone secretion after receiving severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination are limited. If nausea, headache, and confusion are observed immediately after SARS-CoV-2 vaccination, clinicians should consider the presence of hyponatremia. As similar case reports to date have presented with severe hyponatremia, prompt treatment may be required.

13.
Bioact Mater ; 28: 348-357, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37334067

RESUMEN

Magnesium phosphate bone cement has become a widely used orthopedic implant due to the advantages of fast-setting and high early strength. However, developing magnesium phosphate cement possessing applicable injectability, high strength, and biocompatibility simultaneously remains a significant challenge. Herein, we propose a strategy to develop high-performance bone cement and establish a trimagnesium phosphate cement (TMPC) system. The TMPC exhibits high early strength, low curing temperature, neutral pH, and excellent injectability, overcoming the critical limitations of recently studied magnesium phosphate cement. By monitoring the hydration pH value and electroconductivity, we demonstrate that the magnesium-to-phosphate ratio could manipulate the components of hydration products and their transformation by adjusting the pH of the system, which will influence the hydration speed. Further, the ratio could regulate the hydration network and the properties of TMPC. Moreover, in vitro studies show that TMPC has outstanding biocompatibility and bone-filling capacity. The facile preparation properties and these advantages of TMPC render it a potential clinical alternative to polymethylmethacrylate and calcium phosphate bone cement. This study will contribute to the rational design of high-performance bone cement.

14.
RSC Adv ; 13(28): 19585-19594, 2023 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-37388144

RESUMEN

NiO-based composites exhibit high catalytic activity for the oxygen evolution reaction (OER). Herein, high-performance NiO/Ni/C nanosheet catalysts were obtained by liquid-phase pulsed plasma (LPP), which was generated between two nickel electrodes in ethylene glycol (EG) solution by a homemade high-voltage pulse power supply. Melted nickel nanodrops were ejected from nickel electrodes which were bombarded by the energetic plasma. Simultaneously, high-temperature nickel nanodrops promoted the decomposition of the organics which were converted in the EG solution by the catalysis of LPP and formed hierarchical porous carbon nanosheets. Due to the high surface energy of the hierarchical porous carbon nanosheets, the spherical particles of Ni/NiO were adsorbed on the surface to compose the NiO/Ni/C composites. The pore size distribution of the composites could be controlled with different EG concentrations. When the EG concentration was 10 vol% (EG30), the composites possessed a H2 + H2 + H3 type pore size distribution and maximum active site area, leading to an exceptional OER activity (289.2 mV overpotential at 10 mA cm-2).

15.
J Clin Med ; 12(12)2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37373778

RESUMEN

Bone conduction implants (BCIs) and middle ear implants (MEIs) are promising options for individuals with persistent chronic inflammation of the middle or outer ear. However, the structure of the middle ear is often altered in patients who undergo mastoidectomy or posterior wall removal for refractory otitis media, leaving uncertainty regarding the efficacy of hearing devices. Only a few studies have examined auditory outcomes based on the etiology of hearing impairment. We investigated hearing outcomes, including speech audiometry, in patients who underwent implantation after surgery for refractory otitis media. Our findings indicated that patients who received BCIs or MEIs achieved favorable hearing outcomes. Furthermore, a correlation was observed between the preoperative bone-conduction threshold at 1 kHz in the better ear and the sound-field threshold at 1 kHz with BCIs, whereas no correlation was observed between the preoperative bone-conduction threshold and the sound-field threshold with MEIs. This study highlights the positive impact of BCIs and MEIs in patients who undergo implantation after surgery for refractory otitis media. Additionally, our study identified parameters that predict postoperative efficacy.

16.
Ear Nose Throat J ; : 1455613231177188, 2023 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-37231666

RESUMEN

A 72-year-old Japanese man with a 4-month history of hoarseness and 1-week history of difficulty breathing was admitted to our department. He underwent right total nephrectomy for primary clear cell-type renal cell carcinoma (RCC) 6 years ago and left partial nephrectomy for the metastasis 4 years ago. Flexible laryngeal fiberscope examination revealed bilateral subglottic stenosis without obvious mucosal lesions. Enhanced computerized tomography (CT) scan of the neck revealed that the cricoid cartilage had become bilaterally expansive and tumorous lesion exhibiting enhancement. We performed tracheostomy on the appointed day and biopsied the tumor in the cricoid cartilage via the skin incision. Results of histologic and immunohistologic examinations for AE1/AE3, CD10, and vimentin positivity were consistent with clear cell-type RCC. Chest and abdomen CT scans revealed a few tiny metastases in the upper lobe of the left lung but no recurrence in the abdomen. At 2 weeks from the day of tracheostomy, total laryngectomy was performed. Postoperatively, the patient was treated transorally with axitinib (10 mg/day) and as of 12 months he remains alive with unchanging lung metastasis. Next-generation sequencing of targeted regions using a surgical specimen from the tumor revealed a frameshift mutation in the von Hippel-Lindau gene (p.T124Hfs*35) and a missense mutation in the TP53 gene (p.H193R).

17.
ACS Appl Mater Interfaces ; 15(22): 27399-27410, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37226047

RESUMEN

Implantable electrochemical sensor holds great promise in the real-time monitoring of dopamine (DA) to regulate body function. However, the real application of these sensors is limited by the weak current signal of DA in the human body and the poor compatibility of the on-chip microelectronic devices. In this work, a SiC/graphene composite film was fabricated using laser chemical vapor deposition (LCVD) and employed as a DA sensor. The graphene in the porous nanoforest-like SiC framework offered efficient channels for electronic transmission, leading to an enhanced electron transfer rate and consequently an increased current response for DA detection. The three-dimensional (3D) porous network also facilitated the exposure of more catalytic active sites toward DA oxidation. Besides, the wide distribution of graphene in the nanoforest-like SiC films reduced the interfacial resistance of the charge transfer. The SiC/graphene composite film exhibited excellent electrocatalytic activity toward DA oxidation with a low detection limit of 0.11 µM and a high sensitivity of 0.86 µA·µM-1·cm-2. The film electrode also showed a wide linear response for DA in 0.5-78 µM, along with good selectivity, repeatability, and reproducibility. Furthermore, the cell counting kit-8 (CCK-8) and live-dead assays revealed that the film is also biocompatible for biomedical applications. Therefore, the nanoforest-like SiC/graphene composite film via the CVD process enables a promising candidate for an integrated miniature DA biosensor with high detection performance.


Asunto(s)
Enfermedades Cardiovasculares , Grafito , Humanos , Técnicas Electroquímicas/métodos , Dopamina/química , Grafito/química , Reproducibilidad de los Resultados , Electrodos
18.
Small ; 19(30): e2300154, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37060226

RESUMEN

The oriented growth of ß-Ga2 O3 films has triggered extensive interest due to the remarkable and complex anisotropy found in the ß-Ga2 O3 bulks. Remarkable properties, including stronger solar-blind ultraviolet (SBUV) absorption, better mobility, and higher thermal conductivity, are usually observed along <010> direction as compared to other low-index axes. So far, <010>-oriented ß-Ga2 O3 film growth has been hindered by the lack of suitable substrates and higher surface energy of the (010) crystal plane. Herein, the first growth of uniquely <010>-oriented ß-Ga2 O3 films on quartz substrates by laser chemical vapor deposition (LCVD) are reported. By investigating the effects of deposition temperature (Tdep ) and O2 flow rate (RO2 ) on the growth of ß-Ga2 O3 films, it is found that the formation of <010> orientation is closely related to the higher stability of oxygen close-packed planes under O-rich condition. As a result, a grain size of up to ≈2 µm and a deposition rate of up to ≈ 40 µm h-1 are obtained. Metal-semiconductor-metal (MSM) type detector based on <010>-oriented ß-Ga2 O3 film exhibits ultra-fast response speed, 1-2 orders of magnitude higher than those of most detectors based on ß-Ga2 O3 films with other orientations.

19.
Nanomaterials (Basel) ; 13(6)2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-36985980

RESUMEN

Single-walled carbon nanotubes (SWCNTs) modified by introducing non-six-membered ring defects, such as five- and seven-membered rings, have attracted considerable attention because their conductivity is enhanced by increasing the electronic density of states at the Fermi energy level. However, no preparation method exists to efficiently introduce non-six-membered ring defects into SWCNTs. Herein, we attempt to introduce non-six-membered ring defects into SWCNTs by defect rearrangement of the nanotube framework using a fluorination-defluorination process. Defect-introduced SWCNTs were fabricated from SWCNTs fluorinated at 25 °C for different reaction times. Their structures were evaluated, and their conductivities were measured by operating a temperature program. Structural analysis of the defect-induced SWCNTs using X-ray photoelectron spectroscopy, Raman spectroscopy, high-resolution transmission electron microscopy, and visible-near-infrared spectroscopy did not reveal the presence of non-six-membered ring defects in the SWCNTs but indicated the introduction of vacancy defects. Meanwhile, conductivity measurements performed by operating a temperature program showed that the defluorinated SWCNTs prepared from SWCNTs fluorinated for 3 min (deF-RT-3m) exhibited decreased conductivity owing to the adsorption of water molecules to non-six-membered ring defects, thereby implying the possibility of non-six-membered ring defects being introduced into deF-RT-3m.

20.
Anesth Prog ; 70(1): 34-36, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36995954

RESUMEN

Vasovagal syncope (VVS) or reflex is usually caused by physical and mental stress-related factors, like pain, anxiety, and fear, and it is one of the most frequent complications during dental treatment. Two patients, both with histories of dental phobia and of VVS during vaccination, venipuncture, and dental treatment with local anesthetics, were scheduled for dental treatment under intravenous (IV) sedation. However, both experienced episodes of VVS that occurred during venipuncture using a 24-gauge indwelling needle. We determined that pain was the main trigger of VVS for these patients and attempted to reduce venipuncture-associated pain using 60% lidocaine tape applied 3 hours before venipuncture at their next dental visits, respectively. Use of the lidocaine tape was successful and permitted comfortable placement of the IV catheter without any onset of VVS.


Asunto(s)
Síncope Vasovagal , Humanos , Síncope Vasovagal/etiología , Síncope Vasovagal/prevención & control , Lidocaína , Flebotomía/efectos adversos , Anestésicos Locales , Dolor/etiología
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