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1.
Food Sci Biotechnol ; 33(2): 287-295, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38222907

ABSTRACT

Exposure to heavy metals in water and food poses a significant threat to human well-being, necessitating the efficient removal of these contaminants. The process of urban development exacerbates heavy metal pollution, thereby increasing risks to both human health and ecosystems. Heavy metals have the capacity to enter the food chain, undergo bioaccumulation and magnify, ultimately resulting in adverse effects on human health. Therefore, implementing effective pollution control measures and adopting sustainable practices are crucial for mitigating exposure and associated health risks. Various innovative approaches, including adsorption, ion exchange, and electrochemical technology, are currently being actively investigated to cope with the issue of heavy metal contamination. These innovative methods offer benefits such as efficient recycling, cost-effectiveness and environmental friendliness. In this review, we summarize recent advances for removing heavy metals from water, soil and food, providing valuable guidance for environmental engineers and researchers seeking to address contamination challenges.

2.
In Vivo ; 38(1): 431-436, 2024.
Article in English | MEDLINE | ID: mdl-38148064

ABSTRACT

BACKGROUND/AIM: Vasopressin injected during myomectomy is known to effectively reduce bleeding but is sometimes associated with intraoperative vasoconstriction and hypertension due to systemic absorption. Although there is a growing preference for the use of diluted vasopressin, evidence of its effect and safety is still lacking. PATIENTS AND METHODS: We performed a randomized controlled pilot trial to evaluate the effect and safety of vasopressin diluted in a constant volume during robot-assisted laparoscopic myomectomy (RALM), where a total of 39 women with uterine fibroids were randomly assigned into the following three groups (group 1, 0.2 IU/ml; group 2, 0.1 IU/ml; group 3, 0.05 IU/ml with a total of 100 ml of normal saline). The primary endpoint was to compare estimated blood loss (EBL), and the secondary endpoints were to compare postoperative value and drop ratio of hemoglobin, operation time, transfusion, hospitalization, and complications among the three groups. RESULTS: There were no differences in the number and largest size of uterine fibroids, total weight of uterine fibroids, console time, and volumes of intravenous fluid administered during RALM among the three groups, whereas combined operation was performed more commonly in group 2 than in groups 1 and 3 (53.9% vs. 0 to 7.7%; p=0.01). The primary and secondary endpoints were also not different among the three groups. However, two patients in group 1 (15.4%) showed vasopressin-related hypertension. CONCLUSION: Vasopressin diluted in a volume of 100 ml showed an effective hemostatic effect and safety during RALM (Trial No. NCT04874246 in ClinicalTrial.gov).


Subject(s)
Hypertension , Laparoscopy , Leiomyoma , Robotics , Uterine Myomectomy , Uterine Neoplasms , Humans , Female , Uterine Myomectomy/adverse effects , Uterine Neoplasms/drug therapy , Uterine Neoplasms/surgery , Pilot Projects , Leiomyoma/drug therapy , Leiomyoma/surgery , Vasopressins , Blood Loss, Surgical/prevention & control , Laparoscopy/adverse effects , Hypertension/etiology
3.
Nanomaterials (Basel) ; 13(21)2023 Oct 26.
Article in English | MEDLINE | ID: mdl-37947684

ABSTRACT

Fluoride ion is essential for health in small amounts, but excessive intake can be toxic. Meeting safety regulations for managing fluoride ion emissions from industrial facilities with both cost-effective and eco-friendly approaches is challenging. This study presents a solution through a chemical-free process, producing a boehmite (AlOOH) adsorbent on aluminum sheets. Utilizing cost-effective Al foil and DI water, rather than typical precursors, yields a substantial cost advantage. The optimized AlOOH adsorbent demonstrated a high fluoride ion removal rate of 91.0% in simulated wastewater with fluoride ion concentrations below 20 ppm and displayed a similar performance in industrial wastewater. Furthermore, the AlOOH adsorbent exhibited excellent reusability through a simple regeneration process and maintained stable performance across a wide pH range of 4 to 11, demonstrating its capability to adsorb fluoride ions under diverse conditions. The efficiency of the AlOOH adsorbent was validated by a high fluoride ion removal efficiency of 90.9% in a semi-batch mode flow cell, highlighting its potential applicability in engineered water treatment systems. Overall, the AlOOH adsorbent developed in this study offers a cost-effective, eco-friendly, and sustainable solution for effectively removing fluoride ion from surface waters and industrial wastewaters.

4.
Ann Rehabil Med ; 47(4): 291-299, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37644715

ABSTRACT

OBJECTIVE: To investigate the relationship between the torque onset angle (TOA) of the isokinetic test for knee extensors in the paretic side and walking related balance in subacute stroke patients. METHODS: We retrospectively reviewed patients with first-ever strokes who have had at least two isokinetic tests within 6 months of onset. 102 patients satisfied the inclusion criteria. The characteristics of walking related balance were measured with the Berg Balance Scale sub-score (sBBS), Timed Up and Go test (TUG), 10-m Walk Test (10MWT) and Functional Independence Measure sub-score (sFIM). The second isokinetic test values of the knee extensor such as peak torque, peak torque to weight ratio, hamstring/quadriceps ratio, TOA, torque stop angle, torque at 30 degrees, and peak torque asymmetry ratio between paretic and non-paretic limb were also taken into account. Pearson's correlation, simple regression and multiple regression analysis were used to analyze the correlation between TOA and walking related balance. RESULTS: TOA of the knee extensor of the paretic limb showed significant correlations with BBS, sBBS, TUG, 10MWT, and sFIM according to Pearson's correlation analysis. TOA also had moderate to good correlations with walking related balance parameters in partial correlation analysis. In multiple regression analysis, TOA of the paretic knee extensor was significantly associated with walking related balance parameters. CONCLUSION: This study demonstrated that TOA of the paretic knee extensor is a predictable parameter of walking related balance. Moreover, we suggest that the ability to recruit muscle quickly is important in walking related balance.

5.
J Clin Med ; 12(3)2023 Feb 02.
Article in English | MEDLINE | ID: mdl-36769835

ABSTRACT

Carcinosarcomas (malignant mixed Mullerian tumors) of a female genital organ are rare tumors associated with a poor survival. The purpose of this study was to identify site-specific differences in the incidence and prognosis in carcinosarcomas originating in the uterus, cervix, or ovary. The data of patients with gynecologic carcinosarcomas were extracted from the Surveillance, Epidemiology, and End Results (SEER) database between 2000 and 2016. The characteristics of gynecologic carcinosarcomas were compared using Pearson X2 and Fisher's exact tests. Kaplan-Meier models were used for cause-specific survival (CSS) analysis. The cohort included 7086 females, including 5731 cases of uterine carcinosarcoma, 161 cervical carcinosarcomas, and 1193 ovarian carcinosarcomas. The age-adjusted incidence rates of uterine, cervical, and ovarian carcinosarcoma were 3.9, 0.1, and 0.6 per 1,000,000, respectively. In the distribution of carcinosarcoma incidence by race, compared with the uterus or cervix, those originating from the ovary were unequally distributed in Caucasians (84.4% versus 69.6%, 67.7%; p < 0.001). The incidence of uterine carcinosarcoma steadily increased over time, from 2.2 in 2000 to 5.5 in 2016 (per 1,000,000), while cervical or ovarian carcinosarcoma showed no significant difference in incidence. The five-year CSS rates based on the site of origin (uterus, cervix, and ovary) were 39.9%, 33.1%, and 25.8%, respectively. The incidence rates of gynecologic carcinosarcoma, especially uterine carcinosarcoma, are gradually increasing. Although uterine carcinosarcoma is associated with a higher incidence than the others, it has a better prognosis compared with ovarian and cervical carcinosarcoma. The survival rates were worst in ovarian carcinosarcoma.

6.
Food Sci Biotechnol ; 32(2): 221-228, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36647521

ABSTRACT

Pollutant exposure due to industrial development increases oxidative stress in human bodies. Dietary intake of antioxidant shows a protective effect against oxidative damage induced by oxidative stress. Therefore, the development of natural antioxidants is needed. In this study, the antioxidant activities of some Nepali medicinal plant extracts were measured. Using Rose bengal and 3,3',5,5'-tetramethylbenzidine, a novel assay was utilized to evaluate the singlet oxygen scavenging capacity, and showed a strong correlation with other antioxidant assays. Also, antioxidant capacities based on four assays including the singlet oxygen scavenging assay were highly correlated (≥ 0.858) with the total phenolic contents in the medicinal plant extracts. Among the selected extracts, Persicaria capitata, Elaphoglossum marginatum and Eurya acuminata showed the highest antioxidant capacities. Overall, this study presents a novel approach for evaluating singlet oxygen scavenging capacity, and performed a screening of antioxidant capacities of 54 Nepali herbal medicines. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-022-01175-z.

7.
Int Dent J ; 73(3): 370-376, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36075760

ABSTRACT

OBJECTIVES: This study aimed to evaluate implants from different manufacturers and determine whether implant-healing abutment interface has a significant impact on implant seal. METHODS: An air-injection pressure measurement test was performed on implants with either line-contact (modified TSIII [TSM] and Bone Level Tapered [BLT]) or partial face-contact (BlueDiamond [BD], SuperLine [SL], ISII, and UFII) interface design from 6 different manufacturers. Forty implants per implant type were analysed. Pressure data were evaluated with Kruskal-Wallis test and Dunn's post hoc analysis (statistical significance was set at P < .05). RESULTS: BLT implants leaked when the mean pressure was increased to 199.9 kPa. The following implants showed mean leakage pressures of 182.9 (TSM), 157.4 (BD), 112.9 (SL), 101.8 (ISII), and 30.6 (UFII). There was a significant difference between line-contact and partial face-contact implants (P < .001). CONCLUSIONS: The implant interface design has a significant impact on implant microbial leakage. Implants with a line-contact interface exhibited a higher resistance to leakage than those with partial face-contact.


Subject(s)
Dental Implants , Dental Leakage , Humans , Dental Abutments , Surface Properties
8.
Obstet Gynecol Sci ; 66(1): 26-33, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36325754

ABSTRACT

OBJECTIVE: To identify factors that affect the participation of female immigrants in their 20s in the national cervical cancer screening programs. METHODS: Data were obtained from the National Health Insurance Services from 2016 to 2017. A total of 17,730 women who agreed to undergo cervical cancer screening during 2016-2017 were included in the study. RESULTS: Of the 17,730 women, 8,149 (46%) participated in cervical cancer screening, whereas, 9,581 (54%) did not. Logistic regression analysis of factors related to cervical cancer screening showed that the odds ratio (OR) of screening was higher in short duration of stay (OR, 1.18; 95% confidence interval [CI], 1.03-1.35), Chinese nationality (OR, 1.43; 95% CI, 1.28-1.59), unemployment (OR, 1; 95% CI, reference), participation in general health screening (OR, 4.16; 95% CI, 3.24-5.33), and comorbidities (OR, 1.16; 95% CI, 1.09-1.24) when compared to the other populations. The highest OR was associated with participation in general health screening. CONCLUSION: Appropriate programs should be developed to increase participation of socially vulnerable groups in cervical cancer screening. Such programs will improve awareness regarding cervical cancer screening and reduce disparities in healthcare.

9.
Toxins (Basel) ; 14(9)2022 09 07.
Article in English | MEDLINE | ID: mdl-36136563

ABSTRACT

The incidence of eutrophication is increasing due to fertilizer abuse and global warming. Eutrophication can induce the proliferation of cyanobacteria such as Microcystis, which produces microcystins. Microcystins are toxic to specific organs such as the liver and the heart. Thus, monitoring of microcystins is strongly required to control drinking water and agricultural product qualities. However, microcystins could be adsorbed by plastic materials during sample storage and preparation, hindering accurate analysis. Therefore, the current study examined the recovery rate of microcystins from six plastics used for containers and eight plastics used for membrane filters. Among the six plastics used for containers, polyethylene terephthalate showed the best recovery rate (≥81.3%) for 48 h. However, polypropylene, polystyrene, and high- and low-density polyethylenes showed significant adsorption after exposure for 1 hr. For membrane materials, regenerated cellulose (≥99.3%) showed the highest recovery rate of microcystins, followed by polyvinylidene fluoride (≥94.1%) and polytetrafluoroethylene (≥95.7%). The adsorption of microcystins appeared to be strongly influenced by various molecular interactions, including hydrophobic interaction, hydrogen bonding, and electrostatic interaction. In addition, microcystins' functional residues seemed to be critical factors affecting their adsorption by plastic materials. The present study demonstrates that polyethylene terephthalate and regenerated cellulose membrane are suitable plastic materials for the analysis of microcystins.


Subject(s)
Drinking Water , Microcystis , Adsorption , Drinking Water/analysis , Fertilizers/analysis , Microcystins/analysis , Plastics , Polyethylene Terephthalates , Polyethylenes/analysis , Polypropylenes , Polystyrenes , Polytetrafluoroethylene
10.
Biomed Res Int ; 2022: 8720412, 2022.
Article in English | MEDLINE | ID: mdl-35958810

ABSTRACT

Miniscrew has been used widely as an effective orthodontic anchorage with reliable stationary quality, ease of insertion and removal techniques, immediate or early loading, flexibility in site insertion, less trauma, minimal patient cooperation, and lower price. Nonetheless, it is not free of complications, and they could impact not only the miniscrew success rate but also patients' oral health. In this article, literature was searched and reviewed electronically as well as manually to evaluate the complications of orthodontic miniscrew. The selected articles are analyzed and subcategorized into complications during and after insertion, under loading, and during and after removal along with treatment if needed according to the time. In addition, the noteworthy associated factors such as the insertion and removal procedures, characteristics of both regional and local anatomic structures, and features of the miniscrew itself that play a significant role in the performance of miniscrews are also discussed based on literature evidence. Clinicians should notice these complications and their related factors to make a proper treatment plan with better outcomes.


Subject(s)
Orthodontic Anchorage Procedures , Bone Screws/adverse effects , Humans , Orthodontic Anchorage Procedures/adverse effects , Orthodontic Anchorage Procedures/methods
11.
Food Sci Biotechnol ; 31(8): 971-984, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35873381

ABSTRACT

Sargassum, a brown seaweed, has been used traditionally as food and medicine in Korea, China, and Japan. Sargassum spp. contain bioactive substances associated with health benefits, including anti-inflammatory and antioxidant effects. Thirty Sargassum spp. inhabit the Korean coast. However, their health benefits have yet to be systematically summarized. Therefore, the purpose of this article was to review the health benefits of these 30 Sargassum spp. grown off the Korean coast based on their health benefits, underlying mechanisms, and identified bioactive compounds. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-022-01050-x.

12.
Dent Mater J ; 41(5): 731-740, 2022 Oct 02.
Article in English | MEDLINE | ID: mdl-35793939

ABSTRACT

The relative dentin abrasivity-profilometry equivalent values were compared using non-contact profilometry with three subtypes of regular toothpaste and two subtypes of whitening toothpaste containing sodium bicarbonate and 35% hydrogen peroxide. Bovine dentin specimens were assigned to six groups: regular toothpaste (R): R1 (BAMBOO SALT GUM OINTMENT); R2 (MEDIAN TARTAR ORIGINAL); R3 (PERIOE Alpha), Reference slurry: RS (calcium pyrophosphate), whitening toothpaste (W): W1 (NET. WT); W2 (Vussen 28 WHITENING). Relative dentin abrasion-profilometry equivalent (RDA-PE) was determined by brushing 10,000 times (n=8). The pH of the toothpaste was measured (n=5) and the abrasive constituents of the toothpaste was analyzed by FE-SEM and EDS. The RDA-PE values ranged from 26 to 166, and the pH level ranges were 4.928-9.153. The RDA-PE value of the whitening toothpaste containing hydrogen peroxide was not high compared with that of the regular toothpaste. The RDA-PE values of whitening toothpaste could vary depending on the mechanism and ingredients of the whitening agents.


Subject(s)
Bleaching Agents , Tooth Abrasion , Animals , Calcium Pyrophosphate , Cattle , Dentin , Hydrogen , Materials Testing , Ointments , Sodium Bicarbonate , Toothbrushing/methods , Toothpastes/pharmacology
13.
Dent Mater J ; 41(5): 767-773, 2022 Oct 02.
Article in English | MEDLINE | ID: mdl-35858791

ABSTRACT

The microbial leakage at the implant-abutment interface (IAI) is one cause of peri-implant infection that puts long-term implant stability at risk. The present study compared two types of Morse taper implants in terms of sealing performance at the implanthealing abutment interface. Three implant systems, one of which exhibited a partial face-contact design (TSO) and the other two a line-contact design (TSM and BLT), were analyzed in vitro using two quantitative implant leakage measuring techniques: air-injection pressure measurement test and microbial examination. An in-house-developed device was used to determine implant leakage by recording the initial drop in pressure while injecting air through the implant. The microbial examination measured the absorbances of culture mediums in which the inoculated implants were contained. Significant difference was found between the partial face- and line-contact groups (p<0.001). Both tests revealed that partial face-contact implants are more prone to leakage than line-contact implants.


Subject(s)
Dental Implants , Dental Leakage , Culture Media , Dental Abutments , Dental Implant-Abutment Design , Humans
14.
Small ; 17(44): e2101989, 2021 11.
Article in English | MEDLINE | ID: mdl-34569721

ABSTRACT

Design of interfaces with thermodynamic and kinetic specificity is of great importance for hydrogen storage from both an applied and fundamental perspective. Here, in order to destabilize the metal hydride and protect the dehydrogenated products from oxidizing, a unique core-shell structure of porous Mg(BH4 )2 -based framework with a thin layer (no more than 5 nm) of MgCl2 additives on the surface, has been proposed and synthesized via a wet-chemical method. The local structure and electronic state of the present complex system are systematically investigated to understand the correlation between the distribution of additives and dehydrogenation property of Mg(BH4 )2 . A significant improvement is achieved for hydrogen desorption with chlorides: initial hydrogen release from MgCl2 decorated γ-phase Mg(BH4 )2 particles commences at 100 °C and reaches a maximum of 9.4 wt% at 385 °C. Besides the decreased decomposition temperature, an activation barrier of about 76.4 kJ mol-1 lower than that of Mg(BH4 )2 without MgCl2 is obtained. Moreover, MgCl2 decoration can also prevent the whole decomposed system (both Mg- and B- elements) from oxidizing, which is a necessary condition to reversibility.


Subject(s)
Hydrogen , Magnesium , Borohydrides , Porosity , Thermodynamics
15.
ChemSusChem ; 14(18): 3801-3805, 2021 Sep 20.
Article in English | MEDLINE | ID: mdl-34245491

ABSTRACT

Despite their superior stability and facile handling, ionic polymers have limited solubility in most organic solvents, restricting the range of substrates and reaction conditions to which they can be applied. To overcome this solubility issue, the present study presents a solvent-free mechanochemical reaction. Specifically, a post-polymerization modification of ammonium-functionalized polyether was demonstrated using a solvent-free vibrational ball-milling technique. The formation of imine bonds between the ionic polymer and an aromatic aldehyde led to the complete conversion to imine within 1 h without any bond breakage on the polymer backbone. The viability of this approach for a wide range of aldehydes was also evaluated, highlighting the potential of the mechanochemical post-polymerization modification of polymers that are inaccessible by conventional solution approaches.

16.
Foods ; 10(6)2021 Jun 19.
Article in English | MEDLINE | ID: mdl-34205436

ABSTRACT

To investigate the adipogenesis and lipolysis effects of the Bacillus subtilis-fermented white sword bean extract (FWSBE) on 3T3-L1 adipocytes, we treated 3T3-L1 preadipocytes before and after differentiation with FWSBE and measured triglyceride, free glycerol, mRNA, and protein levels. First, FWSBE reduced the cell viability of 3T3-L1 pre-adipocytes under 1000 µg/mL conditions. Triglyceride accumulation in 3T3-L1 pre-adipocytes was suppressed, and free glycerol content in mature 3T3-L1 adipocytes was increased in the FWSBE treatment groups, indicating that FWSBE has anti-obesity effects. Further, FWSBE suppressed adipogenesis in 3T3-L1 pre-adipocytes by lowering the protein levels of C/EBPα, PPARγ, and FAS and increasing the level of pACC and pAMPK. Additionally, FWSBE promoted lipolysis in mature 3T3-L1 adipocytes by increasing the transcription levels of Ppara, Acox, and Lcad and the protein levels of pHSL and ATGL. Thus, we suggest that FWSBE can be a potential dietary supplement because of its anti-obesity properties.

17.
Pediatr Rheumatol Online J ; 19(1): 78, 2021 Jun 02.
Article in English | MEDLINE | ID: mdl-34078404

ABSTRACT

BACKGROUND: This study aimed to assess the occurrence of coronary artery lesions (CAL) in patients with Kawasaki disease (KD) according to serum C-reactive protein (CRP) levels. METHODS: This retrospective analysis was based on the nationwide survey of KD conducted in the Republic of Korea between 2015 and 2017. We enrolled 9131 patients and defined low (< 3 mg/dL) and high (≥3 mg/dL) CRP groups. Demographic data, clinical characteristics, z-scores, and scores based on the Japanese criteria for CAL were compared between the two groups. Logistic regression analysis was used to identify CAL risk factors. RESULTS: The low CRP group accounted for 23% of patients. The mean age at diagnosis was higher in high CRP group compared to the low CRP group (34.4 ± 24.9 vs 31.7 ± 24.8 months, p < 0.001). Fever duration before treatment was not significantly different between the two groups (5.1 ± 1.7 days vs. 5.2 ± 2.1 days; p = 0.206). A non-response to intravenous immunoglobulin treatment was found in 1377 patients (20.1%) and 225 patients (11.7%) in the high and low CRP groups, respectively (p < 0.001). CAL were found in 12.9 and 18.3% of the high and low CRP patients, respectively (p < 0.001), based on z-scores; and in 9.9 and 12.5%, respectively (p = 0.001), based on the Japanese criteria in the acute phase. The giant coronary artery aneurysm occurrence ratio was similar between groups (p = 1.0). CONCLUSIONS: CAL occurred in patients with both high and low CRP. Therefore, patients with KD should be carefully monitored regardless of their CRP levels.


Subject(s)
C-Reactive Protein/analysis , Coronary Aneurysm , Immunoglobulins, Intravenous , Mucocutaneous Lymph Node Syndrome , Biomarkers, Pharmacological/analysis , Child, Preschool , Coronary Aneurysm/diagnostic imaging , Coronary Aneurysm/etiology , Coronary Vessels/diagnostic imaging , Coronary Vessels/pathology , Female , Humans , Immunoglobulins, Intravenous/administration & dosage , Immunoglobulins, Intravenous/adverse effects , Male , Mucocutaneous Lymph Node Syndrome/blood , Mucocutaneous Lymph Node Syndrome/complications , Mucocutaneous Lymph Node Syndrome/physiopathology , Mucocutaneous Lymph Node Syndrome/therapy , Outcome Assessment, Health Care , Patient Acuity , Republic of Korea/epidemiology , Retrospective Studies , Risk Factors
18.
Life (Basel) ; 10(10)2020 Oct 02.
Article in English | MEDLINE | ID: mdl-33023080

ABSTRACT

Despite the introduction of next-generation sequencing in the realm of DNA sequencing technology, it is not often used in the investigation of oral squamous cell carcinoma (OSCC). Oral cancer is one of the most frequently occurring malignancies in some parts of the world and has a high mortality rate. Patients with this malignancy are likely to have a poor prognosis and may suffer from severe facial deformity or mastication problems even after successful treatment. Therefore, a thorough understanding of this malignancy is essential to prevent and treat it. This review sought to highlight the contributions of next-generation sequencing (NGS) in unveiling the genetic alterations and differential expressions of miRNAs involved in OSCC progression. By applying an appropriate eligibility criterion, we selected relevant studies for review. Frequently identified mutations in genes such as TP53, NOTCH1, and PIK3CA are discussed. The findings of existing miRNAs (e.g., miR-21) as well as novel discoveries pertaining to OSCC are also covered. Lastly, we briefly mention the latest findings in targeted gene therapy and the potential use of miRNAs as biomarkers. Our goal is to encourage researchers to further adopt NGS in their studies and give an overview of the latest findings of OSCC treatment.

19.
Angew Chem Int Ed Engl ; 59(50): 22570-22576, 2020 12 07.
Article in English | MEDLINE | ID: mdl-32914933

ABSTRACT

The application of piezoelectricity for the generation of trifluoromethyl (CF3 ) radicals is reported together with the development of a method for the mechanochemical C-H trifluoromethylation of aromatic compounds. As compared to conventional solution-based approaches, this mechanoredox C-H trifluoromethylation enables cleaner and more sustainable access to a wide range of trifluoromethylated N-heterocycles and peptides, which are important structural motifs in modern drug discovery. This study thus represents an important milestone for future applications of mechanoredox systems to medicinal and pharmaceutical science.

20.
Nanoscale ; 12(15): 8525-8535, 2020 Apr 21.
Article in English | MEDLINE | ID: mdl-32242580

ABSTRACT

We, for the first time, report the development of infrared (IR)-driven photoelectrochemical (PEC) cells using up-conversion glass-ceramics as substrates, which is different from the previous strategies of decorating photocatalysts with up-conversion (UC) rare earth-doped fluoride nanoparticles to utilize IR light. Our approach is more efficient since the use of UC glass-ceramics as substrates of photocatalysts could overcome the chemical instability of fluoride nanoparticles, the blockage of incident light, and the limited exposure of photocatalysts to liquid electrolytes. Oxyfluoride glass-ceramics bearing (Yb,Er)-doped YF3 and (Yb,Tm)-doped YF3 nanocrystals turned out to generate UC green and ultraviolet/blue emissions, respectively, under 980 nm illumination. High-density ZnO nanorods were grown on the up-conversion glass-ceramic substrates by the hydrothermal method and they were subsequently overcoated with CdSe nanocrystals to obtain CdSe/ZnO heterostructures by the chemical bath deposition method. CdSe nanoparticles were excited by both the UC UV emission from Tm and the visible emission from Er and Tm, while ZnO nanorods were excited mostly by the UC UV emission from Tm. Because of the difference in the UC emissions from Er and Tm, two distinct carrier transportations, sensitization and type-II cascade, occurred in the identical CdSe/ZnO heterostructures. Eventually, CdSe/ZnO fabricated on the glass-ceramics bearing (Yb,Tm)-doped YF3 showed increased photocurrent density compared to that fabricated on the glass-ceramics bearing (Yb,Er)-doped YF3 due to the charge separation activated by the type-II cascade structure.

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