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1.
Commun Chem ; 7(1): 91, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643239

RESUMO

Isofagomine (IFG) and its analogues possess promising glycosidase inhibitory activities. However, a flexible synthetic strategy toward both C5a-functionalized IFGs remains to be explored. Here we show a practical synthesis of C5a-S and R aminomethyl IFG-based derivatives via the diastereoselective addition of cyanide to cyclic nitrone 1. Nitrone 1 was conveniently prepared on a gram scale and in high yield from inexpensive (-)-diethyl D-tartrate via a straightforward method, with a stereoselective Michael addition of a nitroolefin and a Nef reaction as key steps. A 268-membered library (134 × 2) of the C5a-functionalized derivatives was submitted to enzyme- or cell-based bio-evaluations, which resulted in the identification of a promising ß-glucocerebrosidase (GCase) stabilizer demonstrating a 2.7-fold enhancement at 25 nM in p.Asn370Ser GCase activity and a 13-fold increase at 1 µM in recombinant human GCase activity in Gaucher cell lines.

2.
JACS Au ; 4(3): 908-918, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38559739

RESUMO

The use of pharmacological chaperones (PCs) to stabilize specific enzymes and impart a therapeutic benefit is an emerging strategy in drug discovery. However, designing molecules that can bind optimally to their targets at physiological pH remains a major challenge. Our previous study found that dibasic polyhydroxylated pyrrolidine 5 exhibited superior pH-selective inhibitory activity and chaperoning activity for human α-galactosidase A (α-Gal A) compared with its monobasic parent molecule, 4. To further investigate the role of different C-2 moieties on the pH-selectivity and protecting effects of these compounds, we designed and synthesized a library of monobasic and dibasic iminosugars, screened them for α-Gal A-stabilizing activity using thermal shift and heat-induced denaturation assays, and characterized the mechanistic basis for this stabilization using X-ray crystallography and binding assays. We noted that the dibasic iminosugars 5 and 20 protect α-Gal A from denaturation and inactivation at lower concentrations than monobasic or other N-substituted derivatives; a finding attributed to the nitrogen on the C-2 methylene of 5 and 20, which forms the bifurcated salt bridges (BSBs) with two carboxyl residues, E203 and D231. Additionally, the formation of BSBs at pH 7.0 and the electrostatic repulsion between the vicinal ammonium cations of dibasic iminosugars at pH 4.5 are responsible for their pH-selective binding to α-Gal A. Moreover, compounds 5 and 20 demonstrated promising results in improving enzyme replacement therapy and exhibited significant chaperoning effects in Fabry cells. These findings suggest amino-iminosugars 5 and 20 as useful models to demonstrate how an additional exocyclic amino group can improve their pH-selectivity and protecting effects, providing new insights for the design of pH-selective PCs.

3.
Eur J Med Chem ; 247: 115005, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36563498

RESUMO

Synthesis of a series of l-iduronic acid (IdoA)- and imino-IdoA-typed C-glycosides for modulating α-l-iduronidase (IDUA) activity is described. In an enzyme inhibition study, IdoA-typed C-glycosides were more potent than imino-IdoA analogs, with the most potent IdoA-typed C-glycoside 27c showing an IC50 value of 1 µM. On the other hand, co-treatment of 12 with rh-α-IDUA in mucopolysaccharidosis type I (MPS I) fibroblasts exhibited a nearly 3-fold increase of the IDUA activity, resulting in a clear reduction of the accumulated heparan sulfate (HS) compared to the exogenous enzyme treatment alone. This is the first report of small molecules facilitating IDUA stabilization, enhancing enzyme activity, and reducing accumulated HS in MPS I cell-based assays, which reveals that small molecules as rh-α-IDUA stabilizers to improve enzyme replacement therapy (ERT) efficacy toward MPS I is feasible and promising.


Assuntos
Mucopolissacaridose I , Humanos , Mucopolissacaridose I/tratamento farmacológico , Mucopolissacaridose I/metabolismo , Iduronidase/farmacologia , Iduronidase/metabolismo , Heparitina Sulfato/farmacologia , Fibroblastos/metabolismo , Glicosídeos
4.
Front Med (Lausanne) ; 9: 843050, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35847774

RESUMO

Background: This study aimed to report a case who was treated with corticosteroids and anti- parasitic agents for ocular toxoplasmosis, but who progressed to acute retinal necrosis, and finally retinal detachment. Case Presentation: A 42-year-old man presented to the ophthalmology clinic with a 1-month history of progressive blurred vision and floaters in his right eye. His best visual acuity (VA) was 20/20 in both eyes. The anterior segment was unremarkable. Funduscopic examination of the right eye revealed active lesions of whitish foci of chorioretinitis with surrounding edema along the superonasal vessels, and retinal vasculitis with perivascular sheathing. Serologic testing was positive for Toxoplasma gondii IgM and IgG, but negative for other virus- and syphilis infections. Ocular toxoplasmosis was diagnosed. Corticosteroids and anti-parasitic agents were given simultaneously, but his right eye VA became 20/100. Funduscopic examination revealed retinal necrosis with localized retinal breaks. We immediately performed focal photocoagulation, however, his right eye progressed to retinal detachment and required vitrectomy. Conclusion: Early administration of systemic corticosteroids in patients with acquired acute ocular toxoplasmosis may lead to complications that impair vision. Intensive observation should be arranged after corticosteroid use.

6.
Cancers (Basel) ; 14(11)2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35681743

RESUMO

Lung cancer-related pleural fluid (LCPF) presents as a common complication with limited treatment. Beyond its function in lipid digestion, bile acid was identified as a potent carcinogen to stimulate tumor proliferation. Previous research indicated a correlation between serum bile acid levels and the risk of developing several gastrointestinal cancers. Our study identified elevated bile acid levels in LCPF and increased farnesoid X receptor (FXR) expression as bile acid nuclear receptors in pleural microvessels of lung adenocarcinoma. Additionally, LCPF stimulated the expression of proteins involved in bile acid synthesis and cholesterol metabolism in HUVECs including CYP7A1, StAR, HMGCR, and SREBP2. LCPF-induced endothelial motility and angiogenesis were counteracted by using ß-muricholic acid as an FXR antagonist. Moreover, we investigated the efficacy of cholesterol-lowering medications, such as cholestyramine, fenofibrate, and atorvastatin, in regulating LCPF-regulated angiogenesis. Along with suppressing endothelial proliferation and angiogenesis, atorvastatin treatment reversed cholesterol accumulation and endothelial junction disruption caused by LCPF. Statin treatment inhibited LCPF-induced endothelial FXR expression as well as the downstream proteins RXR and SHP. Based on the positive findings of suppressing endothelial angiogenesis, our group further incorporated the effect of statin on clinical patients complicated with LCPF. A Kaplan-Meier analysis revealed the clinical benefit of statin exposure in patients with lung adenocarcinoma with LCPF. Conclusively, our study demonstrated the ability of statin to alleviate LCPF-induced angiogenesis in patients with LCPF via FXR modulation.

7.
Artigo em Inglês | MEDLINE | ID: mdl-35329350

RESUMO

Electromagnetic interference is a serious and increasing form of environmental pollution, creating many issues in the areas of health care and industrial manufacturing. The performance of high-precision measurement equipment used in health care and the manufacturing industry is sensitive to electromagnetic interference. However, extremely low-frequency magnetic fields (ELFMF), with a frequency range from 3 to 30 Hz, generated by high-power lines have become the main interference source in high-tech foundries. This paper presents a magnetic cancelling system that works by combining active cancelling technology and passive cancelling technology to reduce the ELFMF around high-precision measurement equipment. The simulation and experimental results show the validity and feasibility of the proposed system.


Assuntos
Campos Eletromagnéticos , Campos Magnéticos
8.
Cells ; 11(5)2022 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-35269438

RESUMO

Impaired wound healing is an ongoing issue that cancer patients undergoing chemotherapy or radiotherapy face. Our previous study regarding lung-cancer-associated pleural fluid (LCPF) demonstrated its propensity to promote endothelial proliferation, migration, and angiogenesis, which are crucial features during cutaneous wound healing. Therefore, the current study aimed to investigate the effect of pleural fluid on cutaneous wound closure in vitro and in vivo using HaCaT keratinocytes and a full-thickness skin wound model, respectively. Both heart-failure-associated pleural fluid (HFPF) and LCPF were sequentially centrifuged and filtered to obtain a cell-free status. Treatment with HFPF and LCPF homogeneously induced HaCaT proliferation with cell cycle progression, migration, and MMP2 upregulation. Western blotting revealed increased PI3K/Akt phosphorylation and VEGFR2/VEGFA expression in HaCaT cells. When treated with the PI3K inhibitor, LCPF-induced keratinocyte proliferation was attenuated with decreased pS6 levels. By applying the VEGFR2 inhibitor, LCPF-induced keratinocyte proliferation was ameliorated by pS6 and MMP2 downregulation. The effect of LCPF-induced cell junction rearrangement was disrupted by co-treatment with a VEGFR2 inhibitor. Compared with a 0.9% saline dressing, LCPF significantly accelerated wound closure and re-epithelization when used as a dressing material in a full-thickness wound model. Histological analysis revealed increased neo-epidermis thickness and dermis collagen synthesis in the LCPF-treated group. Furthermore, LCPF treatment activated basal keratinocytes at the wound edge with the upregulation of Ki-67, VEGFA, and MMP2. Our preliminaries provided the benefit of wet dressing with pleural fluid to improve cutaneous wound closure through enhanced re-epithelization and disclosed future autologous application in cancer wound treatment.


Assuntos
Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Proliferação de Células , Humanos , Queratinócitos/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Cicatrização/fisiologia
9.
Respirol Case Rep ; 10(2): e0901, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35035980

RESUMO

The complications of endobronchial tuberculosis (TB) include bronchostenosis and fistula. We highly recommend that a TB test be included in the diagnosis of endobronchial lesions.

11.
J Acute Med ; 12(4): 158-160, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36761857

RESUMO

Dentures dislodged into throat on bilevel positive airway pressure (BiPAP) ventilation can be overlooked and potentially compromise airway patency. An 81-year-old man with a history of chronic obstructive pulmonary disease (COPD) presented with increased shortness of breath and productive cough for 1 week. Inhaled bronchodilators, parenteral steroids, and BiPAP ventilation were administered for acute exacerbation of COPD complicated with acute hypercapnic respiratory failure. Fifty minutes after receiving BiPAP ventilation, his respiratory condition improved; however, he started to complain of neck pain. The patient remained intolerant to the device 3 hours later, despite receiving assurance that the discomfort might be caused by air pressure through mask ventilation. His throat did not exhibit any abnormality during visual examination. Neck radiographs were subsequently obtained and demonstrated a denture impacted in the hypopharynx. His neck pain resolved after the removal of the dislodged maxillary denture. Denture dislodgement can occur in mask ventilation and compromise airway patency if stuck in the hypopharynx or respiratory tract. Such adverse events may be overlooked on the coexistence of respiratory and pulmonary diseases. A precisely pharyngolaryngeal inspection and complete imaging studies must be performed to facilitate early identification and further retrieval intervention.

12.
ACS Appl Mater Interfaces ; 13(29): 34605-34615, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34264644

RESUMO

A novel bis-4Ph-substituted 9,10-dipehnylanthracene deep blue [1931 CIE (0.15, 0.08)] fluorescent compound, AnB4Ph, has been synthesized and characterized for organic light-emitting diode (OLED) applications. Our experimental study of AnB4Ph excludes the possibility of triplet-triplet annihilation, hybridized local and charge transfer, or thermally activated delayed fluorescent characteristics of the material. Since the solid-state photoluminescence quantum yield of AnB4Ph was determined to be 48%, assuming a 100% for the charge recombination efficiency, the light outcoupling efficiency (ηout) of an AnB4Ph non-doped OLED achieving an external quantum efficiency (EQE) of 5.3% is at least 44%, which is more than twofold higher than 20% for conventional OLEDs. Both grazing incidence wide-angle X-ray scattering (GIWAXS) and angle-dependent photoluminescence (ADPL) measurements reveal AnB4Ph having a high value of order parameter (SGIWAXS) of 0.61 for a ππ stacking along the normal direction and an orientation order parameter (SADPL) for a horizontal emitting dipole moment of -0.50 or Θ (horizontal-dipole ratios) of 100%, respectively. Otherwise, a refractive index (n) measurement provides a n = 1.80 for AnB4Ph thin films. Based on ηout = 1.2 × n-2, the calculated ηout is 37%, which is also in accordance with the results of GIWAXS and ADPL. We have also fabricated the classical fluorescent DPAVBi-doped AnB4Ph OLEDs, which display a true blue [1931 CIE (0.15 and 0.16)] electroluminescence with a high efficiency (EQE = 6.9%), surpassing the conventional ∼5% EQE. Based on an ηout of 42% for DPAVBi-doped AnB4Ph OLEDs, our studies suggest that the extremely horizontally aligned AnB4Ph host material exerts the same horizontal alignment on the DPAVBi dopant molecules.

13.
Enzyme Microb Technol ; 148: 109811, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34116745

RESUMO

Microbial production of industrial chemicals is a sustainable approach to reduce the dependence on petroleum-based chemicals such as acids, alcohols, and amines, in which the cadaverine is a natural diamide and serves as one of the key monomers for biopolymer production. In this study, the constitutive promoter J23100 driven lysine decarboxylase (CadA) for cadaverine production was established and compared in different Escherichia coli strains. The best chassis designed as JW, expressed the highest amount of CadA by using J23100 promoter, showing stable and high copy numbers (i.e., PCN > 100) when culture in the antibiotic-free medium. JW attained a CadA activity of 167 g-DAP/g-DCW-h and had the maximum biocatalyst of 45.6 g-DCW/L in fed-batch fermentation. In addition, JW was able to convert 2.5 M L-lysine to 221 g/L cadaverine, with 86 % yield and 55.3 g/L-h productivity. The whole-cell biocatalyst could be reused over four times at an average of 97 % conversion when supplied half of fresh cells in the reaction. This work developed a stable, constitutive expression, long-term preservation, high-level expression of CadA for DAP production, and paved an alternative opportunity of bio-nylon for industry in the future.


Assuntos
Carboxiliases , Escherichia coli , Cadaverina , Carboxiliases/genética , Escherichia coli/genética , Lisina
15.
Sensors (Basel) ; 20(24)2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33317173

RESUMO

In this paper, a detail design procedure of the real-time trajectory tracking for the nonholonomic wheeled mobile robot (NWMR) is proposed. A 9-axis micro electro-mechanical systems (MEMS) inertial measurement unit (IMU) sensor is used to measure the posture of the NWMR, the position information of NWMR and the hand-held device are acquired by global positioning system (GPS) and then transmit via radio frequency (RF) module. In addition, in order to avoid the gimbal lock produced by the posture computation from Euler angles, the quaternion is utilized to compute the posture of the NWMR. Furthermore, the Kalman filter is used to filter out the readout noise of the GPS and calculate the position of NWMR and then track the object. The simulation results show the posture error between the NWMR and the hand-held device can converge to zero after 3.928 seconds for the dynamic tracking. Lastly, the experimental results show the validation and feasibility of the proposed results.

16.
BMC Complement Altern Med ; 16: 85, 2016 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-26922245

RESUMO

BACKGROUND: Acupuncture is applied for treating numerous conditions in children, but few studies have examined the safe needling depth of acupoints in the pediatric population. In this study, we investigated the depths to which acupuncture needles can be inserted safely in the upper back acupoints of children and the variations in safe depth according to sex, age, weight, and body mass index (BMI). METHODS: We retrospectively studied computed tomography (CT) images of patients aged 4 to 18 years who underwent chest CT at China Medical University Hospital between December 2004 and May 2013. The safe depths of 23 upper back acupoints in the Governor Vessel (GV), Bladder Meridian (BL), Small Intestine Meridian (SI), Gallbladder Meridian (GB) and Spleen Meridian (SP) were measured directly from the CT images. The relationships between the safe depths of these acupoints and sex, age, body weight, and BMI were analyzed. RESULTS: The results indicated significant differences in safe needling depth between boys and girls in most upper back acupoints, except at BL42, BL44, BL45, BL46, GB21 and SP21. Safe depths differed significantly depending on age (p < 0.001), weight (p ≤ 0.01), and BMI (p < 0.05). Multiple regression analysis revealed that weight was the most crucial factor in determining the safe depth. CONCLUSIONS: Sex, age, weight, and BMI are relevant factors in determining the safe needling depths of upper back acupoints in children. Physicians should pay attention to wide variations in needle depth when performing acupuncture.


Assuntos
Pontos de Acupuntura , Terapia por Acupuntura , Dorso , Peso Corporal , Agulhas , Segurança do Paciente , Terapia por Acupuntura/efeitos adversos , Adolescente , Índice de Massa Corporal , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pediatria , Estudos Retrospectivos , Fatores Sexuais , Tomografia Computadorizada por Raios X
17.
Artigo em Inglês | MEDLINE | ID: mdl-26457105

RESUMO

Background. Acupuncture is applied to treat numerous diseases in pediatric patients. Few reports have been published on the depth to which it is safe to insert needle acupoints in pediatric patients. We evaluated the depths to which acupuncture needles can be inserted safely in chest acupoints in pediatric patients and the variations in safe depth according to sex, age, body weight, and body mass index (BMI). Methods. We retrospectively studied computed tomography (CT) images of pediatric patients aged 4 to 18 years who had undergone chest CT at China Medical University Hospital from December 2004 to May 2013. The safe depth of chest acupoints was directly measured from the CT images. The relationships between the safe depth of these acupoints and sex, age, body weight, and BMI were analyzed. Results. The results demonstrated significant differences in depth among boys and girls at KI25 (kidney meridian), ST16 (stomach meridian), ST18, SP17 (spleen meridian), SP19, SP20, PC1 (pericardium meridian), LU2 (lung meridian), and GB22 (gallbladder meridian). Safe depth significantly differed among the age groups (P < 0.001), weight groups (P < 0.05), and BMI groups (P < 0.05). Conclusion. Physicians should focus on large variations in needle depth during acupuncture for achieving optimal therapeutic effect and preventing complications.

18.
Opt Express ; 21(19): 22090-7, 2013 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-24104101

RESUMO

This work demonstrates the enhancement of light extraction of polymer light-emitting diodes (PLEDs) by incorporating a 12-fold photonic quasi crystal (PQC) in the device structure. Multi-exposure two-beam interference technique combined with inductively coupled plasma etching was employed to pattern a 12-fold PQC structure on the ITO film on a glass substrate of the diode. The air-hole coverage (AHC) and etching depth dependences of the light emitting performance of the 12-fold PQC patterned PLEDs were investigated. For AHC within the range between 6.4% and 32.3%, a nearly constant enhancement of the luminance efficiency of the PQC PLEDs was observed. On the other hand, the light emitting performance of the PQC PLEDs is very sensitive to the etching depth. The photoluminescence intensity of the PQC PLEDs increases monotonically with the etching depth. In contrast, the electro luminance efficiency shows a non-monotonic dependence on etching depth with a maximum occurring at 55 nm etching depth. The maximum improvement of luminance efficiency of the 12-fold PQC PLEDs reaches nearly 95% compared with an un-patterned PLED at an injection current of 110 mA.

19.
Nano Lett ; 13(6): 2564-9, 2013 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-23634905

RESUMO

We argue that the structure ordering of self-assembled probing molecular monolayers is essential for the reliability and sensitivity of nanowire-based field-effect sensors because it can promote the efficiency for molecular interactions as well as strengthen the molecular dipole field experienced by the nanowires. In the case of monolayers, we showed that structure ordering could be improved by means of electrical field alignment. This technique was then employed to align multilayer complexes for nanowire sensing applications. The sensitivity we achieved for detection of hybridization between 15-base single-strand DNA molecules is 0.1 fM and for alcohol sensors is 0.5 ppm. The reliability was confirmed by repeated tests on chips that contain multiple nanowire sensors.


Assuntos
Campos Eletromagnéticos , Nanofios , Propriedades de Superfície
20.
J Mater Chem B ; 1(44): 6147-6156, 2013 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-32261000

RESUMO

Functionalized mesoporous bioactive glasses (MBGs) with folic acid (FA) were evaluated specifically for targeting cancer cells because of the high abundance of folate receptors (FRs) in numerous cancer cells. The folate-modified MBG (MBG-FA) was used as a targeted anticancer drug delivery carrier to investigate receptor-mediated targeting characteristics. At the same time, in vitro cytotoxicity and cell uptake of FA-grafted MBG (MBG-FA) to HeLa and L929 cell lines were evaluated. MBG-FA was nontoxic up to a concentration of 200 µg mL-1, and can be specifically raised by HeLa and L929 cells through FA receptor-mediated endocytosis. In vitro cellular uptakes of MBG-FA were investigated with a fluorescence microscope, which demonstrates considerably higher internalization of the MBG-FA by HeLa epithelial carcinoma cells, which are overexpressed folate receptors (FRs), than the cellular uptake by L929 fibroblast cells, which are deficient folate receptors (FRs). Camptothecin (CPT), a water-insoluble anticancer drug, was delivered into cancer cells; surface conjugation with cancer-specific targeting agents increased the uptake into cancer cells relative to non-cancerous fibroblasts. CPT had a sustained release pattern from MBG-FA, and the CPT-loaded MBG-FA exhibited greater cytotoxicity than free CPT because of the increased cell uptake of anticancer drug delivery vehicles mediated by the FA receptor. The structural, morphological, and textural features were characterized well by X-ray diffraction (XRD), transmission electron microscopy (TEM), and N2 adsorption/desorption. The results reveal that the MBG exhibited typical ordered characteristics of the hexagonal mesostructure. Therefore, this study concludes that the MBG-FA system demonstrates great potential in the targeted intelligent drug delivery systems (DDSs) and cancer-therapy fields.

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