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1.
Langmuir ; 40(32): 16946-16958, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39078939

RESUMEN

Microgels have been widely used for stabilizing emulsions due to their softness and stimulus responsiveness. Although ultrastable emulsions have been prepared by microgel nanoparticles, the role of electrostatic interactions on emulsion stability is still a controversial topic and further investigation of the effect of microgel deformability is required. In the present study, neutral poly(N-vinylcaprolactam) (PVCL) and charged poly(N-vinylcaprolactam)-co-methacrylic acid (P(VCL-co-MAA)) microgels were synthesized and further used as emulsifiers to stabilizing emulsion. The P(VCL-co-MAA) microgel has a swelling ratio larger than that of the PVCL microgel in water. The nanomechanical properties of the microgels in water were characterized by atomic force microscopy with using the tip of different radii. The result reveals that the P(VCL-co-MAA) microgel is more deformable than the PVCL counterpart. Stability tests of the emulsions showed that below the volume phase transition temperature (VPTT) of the microgels, both microgel types can stabilize the emulsions under various conditions. Unexpectedly, most of the emulsions still remain stable above the VPTT. Further increasing the temperature to 60 °C, P(VCL-co-MAA) microgel emulsions remained stable at a pH value above the pKa of MAA while the emulsion was unstable below the pKa. However, phase separation occurs in PVCL microgel-stabilized emulsions at 60 °C. These results demonstrate that electrostatic repulsion and deformability of the microgels can enhance the emulsion stability, providing insights into the rational design and preparation of ultrastable Pickering emulsions.

2.
Ecotoxicol Environ Saf ; 285: 117083, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39317073

RESUMEN

Humans are ubiquitously exposed to crotonaldehyde (CRA) endogenously and exogenously. Deeper knowledge of the pharmacological and toxicological characteristics and the mechanisms of CRA on vasculature is urgently needed for prevention of its harmfulness. The effects of acute and prolonged exposure to CRA were studied in rat isolated arteries and arterial smooth muscle cells (ASMCs). Instant exposure to CRA (1-300 µM) concentration-dependently declined the tension of pre-constricted arteries with an irreversible depression on the contractility. Prolonged exposure of rat coronary arteries (RCAs) to CRA concentration- and time-dependently depressed the arterial contractile responsiveness to various vasoconstrictors including depolarization, U46619, serotonin and Bay K8644 (an agonist of voltage-gated Ca2+ channels (VGCCs)). In fresh RCA ASMCs, CRA abated depolarization-induced elevation of intracellular Ca2+ ([Ca2+]i). Electrophysiological study revealed that acute exposure to CRA depressed the functions of Ca2+-activated Cl- channels (CaCCs), voltage-gated K+ (Kv) channels and inward rectifier K+ (Kir) channels in RCA ASMCs. Prolonged exposure of RCAs to CRA reduced the expressions of these ion channels in RCA ASMCs, disordered tissue frames, injured arterial cells, and increased autophagosomes in both ASMCs and endothelial cells. In rat aortic smooth muscle cells (A7r5), CRA exposure decreased the cell viability, elevated the intracellular levels of reactive oxygen species, reduced the mitochondrial membrane potential, and enhanced autophagy. Taken together, the present study for the first time portrays a clearer panoramic outline of the vascular effects and the mechanisms of CRA on arteries, demonstrates that CRA impairs arterial contractility, depresses VGCCs, CaCCs, Kv channels and Kir channels, reduces cell viability, and destroys the arterial histiocytes, and suggests that excessive oxidative stress, mitochondrial dysfunction and autophagy underlie these vascular damages. These findings are significant for the comprehensive evaluation of the vicious effects of CRA on arteries and suggest potential preventive strategies.

3.
Chem Biodivers ; 20(4): e202300085, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36898981

RESUMEN

Cardiovascular diseases (CVDs) are a major global health concern, and oxidative stress is known to play a central role in their pathogenesis. The identification of new agents capable of inhibiting oxidative stress presents a promising strategy for preventing and treating CVDs. Natural products and their derivatives offer a valuable source for drug discovery, and isosteviol, a readily available natural product, is known to exhibit cardioprotective effects. In this study, 22 new D-ring modified isosteviol derivatives were synthesized and evaluated for their cardioprotective effect in vivo using the zebrafish cardiomyopathy model. The findings revealed that derivative 4e exhibited the most potent cardioprotective effect, surpassing its parent compound isosteviol and the positive drug levosimendan. At 1 µM, derivative 4e significantly protected the cardiomyocytes from injury, while at 10 µM it effectively maintained normal heart phenotypes, preventing cardiac dysfunction in zebrafish. Further investigation demonstrated that 4e protected cardiomyocytes from oxidative stress-induced damage by inhibiting reactive oxygen species overaccumulation, activating superoxide dismutase 2 expression, and enhancing the endogenous antioxidant defense system. These results suggest that isosteviol derivatives, particularly 4e, have the potential to serve as a novel class of cardioprotective agents for the prevention and treatment of CVDs.


Asunto(s)
Cardiotónicos , Diterpenos de Tipo Kaurano , Estrés Oxidativo , Animales , Cardiotónicos/farmacología , Cardiotónicos/uso terapéutico , Diterpenos de Tipo Kaurano/farmacología , Diterpenos de Tipo Kaurano/uso terapéutico , Estrés Oxidativo/efectos de los fármacos , Pez Cebra
4.
J Nat Prod ; 85(8): 1945-1958, 2022 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-35943432

RESUMEN

Steviol is an ent-kaurene diterpenoid with interesting pharmacological activity. Several steviol derivatives with an exo-methylene cyclopentanone unit were discovered as potent antitumor agents. However, their poor selectivity for tumor cells relative to normal cells reduces their prospects as potential anticancer drugs. In this study, based on previous work, 32 steviol derivatives, including 28 new analogues, were synthesized. Their cytotoxicity against tumor cells and normal cells was evaluated. Several new derivatives, such as 7a, 7h, and 8f, with improved cytotoxic selectivity and antiproliferative activity were obtained, and the structure-activity relationship correlations were investigated. The new compound 8f displayed potent antiproliferative activity against Huh7 cells (IC50 = 2.6 µM) and very weak cytotoxicity against the corresponding normal cells HHL5 (IC50 = 97.0 µM). Further investigation showed that 8f arrested the cell cycle at the G0/G1 phase and caused reactive oxygen species overproduction, decreased mitochondrial membrane potential, and induced apoptosis of Huh7 cells through inhibition of the PI3K/Akt/mTOR and NF-κB pathway as well as upregulation of Bax/Bcl-2 ratio. The present study suggested that 8f is a promising lead compound for new cancer therapies, and the results presented herein may encourage the further modification of steviol for additional derivatives with enhanced efficacy and selectivity.


Asunto(s)
Antineoplásicos , Diterpenos de Tipo Kaurano , Antineoplásicos/farmacología , Apoptosis , Línea Celular Tumoral , Proliferación Celular , Diterpenos de Tipo Kaurano/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Estructura Molecular , Fosfatidilinositol 3-Quinasas , Relación Estructura-Actividad
5.
Bioorg Chem ; 129: 106142, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36150232

RESUMEN

Cardiovascular diseases (CVDs) remain the leading cause of death globally. Inhibiting ferroptosis and thus preventing cardiac cell death is a promising and effective strategy for cardiomyopathy prevention and therapy. Steviol, an ent-kaurene diterpenoid, possesses broad-spectrum bioactivity. In the present study, with the aim to discover new agents for CVDs treatment, 30 derivatives of steviol, including 22 new ones, were synthesized, and evaluated their protective activity in vivo using the doxorubicin (DOX) induced zebrafish cardiomyopathy model. Our results firstly demonstrated that steviol has promising cardioprotective activity and further modification of steviol can greatly improve the activity. Among the new derivatives, 16d and 16e show the most potent activity. Both 16d (1 µM) and 16e (0.1 µM) effectively maintain the normal heart shape and prevent the cardiac dysfunction impaired by DOX in zebrafish. Their therapeutic efficacy is much superior to the parent natural product, steviol, and positive drug, levosimendan. Further study demonstrated that 16d and 16e inhibit DOX-induced ferroptosis and thus protect cardiomyopathy, by suppressing the glutathione depletion, iron accumulation, and lipid peroxidation, decreasing reactive oxygen species overaccumulation, and restoring the mitochondrial membrane potential. Consequently, due to their unique structure and significant cardioprotective activity with ferroptosis inhibition, new steviol derivatives 16d and 16e merit further research for the development of new cardioprotective drug candidates.


Asunto(s)
Cardiomiopatías , Diterpenos de Tipo Kaurano , Ferroptosis , Animales , Pez Cebra , Diterpenos de Tipo Kaurano/farmacología , Diterpenos de Tipo Kaurano/uso terapéutico , Doxorrubicina/farmacología , Cardiomiopatías/inducido químicamente , Cardiomiopatías/tratamiento farmacológico , Cardiomiopatías/prevención & control
6.
Chem Biodivers ; 19(8): e202200445, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35713419

RESUMEN

Trimetazidine exhibits great therapeutic potential in cardiovascular diseases and mitochondria-mediated cardioprotection by trimetazidine has been widely reported. In this study, to enhance its cardioprotection, the triphenylphosphonium-based modification of trimetazidine was conducted to deliver it specifically to mitochondria. Fifteen triphenylphosphonium (TPP) conjugated trimetazidine analogs were designed and synthesized. Their protective effects were evaluated in vivo using a tert-butyl hydroperoxide (t-BHP) induced zebrafish injury model. Structure-activity relationship correlations revealed the best way to couple the TPP moiety to trimetazidine, and led to a new conjugate (18a) with enhanced therapeutic properties. Compared to trimetazidine, 18a effectively protects against heart injury in the zebrafish model at a much lower concentration. Further study in t-BHP treated zebrafish and H9c2 cells demonstrated that 18a protects against cardiomyocyte death and damage by inhibiting excessive production of ROS, maintaining mitochondrial morphology, and preventing mitochondrial dysfunction. Consequently, 18a can be regarded as a potential therapeutic agent for cardioprotection.


Asunto(s)
Trimetazidina , Animales , Mitocondrias , Miocitos Cardíacos , Trimetazidina/metabolismo , Trimetazidina/farmacología , Trimetazidina/uso terapéutico , Pez Cebra , terc-Butilhidroperóxido/farmacología
7.
Endocr J ; 66(1): 51-63, 2019 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-30393248

RESUMEN

We conducted a systematic review and meta-analysis to evaluate the effect of Berberine on glucose in patients with type 2 diabetes mellitus and identify potential factors may modifying the hypoglycemic effect. We searched PubMed, Embase, the Cochrane Library, China National Knowledge Infrastructure, and Wanfang Database to identify randomized controlled trials that investigated the effect of Berberine. We calculated weighted mean differences (WMD) and 95% confidence interval (CI) for fasting plasma glucose (FPG), postprandial plasma glucose (PPG) and glycated haemoglobin (HbA1c) levels. Twenty-eight studies were identified for analysis, with a total of 2,313 type 2 diabetes mellitus (T2DM) patients. The pool data showed that Berberine treatment was associated with a better reduction on FPG (WMD = -0.54 mmol/L, 95% CI: -0.77 to -0.30), PPG (WMD = -0.94 mmol/L, 95% CI: -1.27 to -0.61), and HbA1c (WMD = -0.54 mmol/L, 95% CI: -0.93 to -0.15) than control groups. Subgroup-analyses indicated that effects of Berberine on blood glucose became unremarkable as the treatment lasted more than 90 days, the daily dosage more than 2 g/d and patients aged more than 60 years. The efficiency of Berberine combined with hypoglycaemics is better than either Berberine or hypoglycaemic alone. The dosage and treatment duration of Berberine and patients' age may modify the effect.


Asunto(s)
Berberina/uso terapéutico , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hemoglobina Glucada/metabolismo , Hipoglucemiantes/uso terapéutico , Diabetes Mellitus Tipo 2/metabolismo , Quimioterapia Combinada , Ayuno/metabolismo , Humanos , Periodo Posprandial
8.
Angew Chem Int Ed Engl ; 58(12): 3784-3789, 2019 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-30701634

RESUMEN

The construction of state-of-the-art hole-transporting materials (HTMs) is challenging regarding the appropriate molecular configuration for simultaneously achieving high morphology uniformity and charge mobility, especially because of the lack of appropriate building blocks. Herein a semi-locked tetrathienylethene (TTE) serves as a promising building block for HTMs by fine-tuning molecular planarity. Upon incorporation of four triphenylamine groups, the resulting TTE represents the first hybrid orthogonal and planar conformation, thus leading to the desirable electronic and morphological properties in perovskite solar cells (PSCs). Owing to its high hole mobility, deep lying HOMO level, and excellent thin film quality, the dopant-free TTE-based PSCs exhibit a very promising efficiency of over 20 % with long-term stability, achieving to date the best performances among dopant-free HTM-based planar n-i-p structured PSCs.

9.
BMC Immunol ; 19(1): 25, 2018 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-30055570

RESUMEN

BACKGROUND: While vaccination remains the most effective method to control hepatitis B virus (HBV) infection, 5-10% of recipients exhibit non-responsiveness to the HB vaccine. Immunological analysis of strong, weak or absent protective antibody responses to the HB vaccine should provide insights into the mechanisms that contribute to non-responsiveness. RESULTS: We investigated the potential involvement of follicular helper T (Tfh) cells in the immune response to HB vaccine, and associations between the miR-17-92 cluster and Tfh cells. We recruited 12 adults who had completed the HB vaccination course during childhood. Following a booster dose of HB vaccine, hepatitis B surface antibody (HBsAb) titers, percentage of PD-1+ICOS+ circulating Tfh (cTfh) and plasma cells, and expression of miR-17-92 were assessed at baseline (before immunization) and after vaccination on days 7 and 14. Notably, the HBsAb level gradually increased after HB vaccination while the proportion of PD-1+ICOS+ cTfh cells was significantly increased on day 7 relative to baseline, so as plasma cells. Expression of miR-18a and miR-17 within the miR-17-92 cluster and HBsAb titers in CD4+ T cells were positively correlated with the PD-1+ICOS+ cTfh cells proportions after HB vaccination. CONCLUSIONS: The increase in HBsAb titers was positively associated with expression of all the components of the miR-17-92 cluster except miR-19a. Our findings indicate that the miR-17-92 cluster contributes to antibody production, and miR-18a and miR-17 are involved in Tfh cells differentiation after HB vaccination.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Vacunas contra Hepatitis B/inmunología , Hepatitis B/prevención & control , MicroARNs/inmunología , Adulto , Linfocitos T CD4-Positivos/citología , Linfocitos T CD4-Positivos/efectos de los fármacos , China , Estudios de Cohortes , Femenino , Anticuerpos contra la Hepatitis B/sangre , Humanos , Proteína Coestimuladora de Linfocitos T Inducibles/inmunología , Masculino , Receptor de Muerte Celular Programada 1/inmunología , Vacunación
10.
BMC Geriatr ; 18(1): 158, 2018 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-29976138

RESUMEN

BACKGROUND: No previous study has evaluated disability in older persons according to the International Classification of Functioning, Disability and Health Framework guidelines. We conducted a more comprehensive investigation of disability and associated factors among older adults receiving home-based care in rural Dongguan, a city in the central Guangdong Province of Southern China. METHODS: A total of 819 individuals aged ≥60 years were recruited from Dongguan home-based care system of via a two-stage selection process. We interviewed participants and assessed their ability level using the Ability Assessment for Older Adults, which defined by a combination of activity of daily living, sensory perception, mental status and social involvement. Conditional probability and Logistic regression approaches were used to assess the strength of association between each pair of conditions. Factors significantly associated with disability were identified via χ2 tests and multinomial ordinal logistic regression. RESULTS: Of the 819 included participants (mean age 87 ±4.7 years), 75.5% were female, 76.7% had any disability, and 62.3% had a mild disability. The occurrence of any deficits significantly increased the likelihood of the co-occurrence of other deficits (odds ratio [OR] > 1, P < 0.05), with the lowest prevalence odds ratio observed among individuals with sensory and communication deficiency (OR: 2.99; 95% confidence interval [CI]: 2.21-4.05). Multivariable ordinal logistic regression analysis indicated that physical activity (OR: 0.96; 95% CI: 0.93-0.99), sedentary behavior (OR: 1.25; 95% CI: 1.13-1.38), not watching television (OR: 1.7; 95% CI: 1.07-2.72) and age (OR: 1.09; 95% CI: 1.02-1.17) were significantly associated with disability. CONCLUSIONS: Impairment of ADL, sensory perception, mental status or social involvement increased the likelihood of risk of the co-occurrence of other deficits. Comprehensive disability among older adults receiving home-based care is associated with age, sedentariness, physical activity and TV viewing.


Asunto(s)
Evaluación de la Discapacidad , Servicios de Atención de Salud a Domicilio , Servicios de Salud Rural , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , China/epidemiología , Estudios Transversales , Ejercicio Físico , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Prevalencia , Conducta Sedentaria , Factores Socioeconómicos , Televisión
11.
J Ethnopharmacol ; 328: 117855, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38346524

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Tea (Camellia sinensis) is a favorite drink worldwide. Tea extracts and green tea main component (-)-epigallocatechin gallate (EGCG) are recommended for various vascular diseases. Anji white tea is a very popular green tea. Its vascular effect profile, the mechanisms, and the contribution of EGCG to its integrated effect need elucidation. AIM: To characterize the vasomotion effects of Anji white tea and EGCG, and to explore possible involvement of voltage-gated Ca2+ channels (VGCCs) and voltage-gated K+ (Kv) channels in their vasomotion effects. MATERIALS AND METHODS: Anji white tea water soaking solution (AJWT) was prepared as daily tea-making process and concentrated to a concentration amounting to 200 mg/ml of dry tea leaves. The tension of rat arteries including aorta, coronary artery (RCA), cerebral basilar artery (CBA), intrarenal artery (IRA), intrapulmonary artery (IPA) and mesenteric artery (MA) was recorded with myographs. In arterial smooth muscle cells (ASMCs) freshly isolated from RCA, the levels of intracellular Ca2+ were measured with Ca2+-sensitive fluorescent probe fluo 4-AM, and Kv currents were recorded with patch clamp. The expressions of VGCCs and Kv channels were assayed with RT-qPCR and immunofluorescence staining. RESULTS: At 0.4-12.8 mg/ml of dry tea leaves, AJWT profoundly relaxed all tested arteries precontracted with various vasoconstrictors about half with a small transient potentiation on the precontractions before the relaxation. KCl-induced precontraction was less sensitive than precontractions induced by phenylephrine (PE), U46619 and serotonin (5-HT). IPA was less sensitive to the relaxation compared with other arteries. AJWT pretreatment for 1 h, 24 h and 72 h time-dependently inhibited the contractile responses of RCAs. In sharp contrast, at equivalent concentrations according to its content in AJWT, EGCG intensified the precontractions in most small arteries, except that it induced relaxation in PE-precontracted aorta and MA, U46619-precontracted aorta and CBA. EGCG pretreatment for 1 h and 24 h did not significantly affect RCA contractile responses. In RCA ASMCs, AJWT reduced, while EGCG enhanced, intracellular Ca2+ elevation induced by depolarization which activates VGCCs. Patch clamp study showed that both AJWT and EGCG reduced Kv currents. RT-qPCR and immunofluorescence staining demonstrated that both AJWT and EGCG reduced the expressions of VGCCs and Kv channels. CONCLUSION: AJWT, but not EGCG, consistently induces vasorelaxation. The vasomotion effects of either AJWT or EGCG vary with arterial beds and vasoconstrictors. Modulation of VGCCs, but not Kv channels, contributes to AJWT-induced vasorelaxation. It is suggested that Anji white tea water extract instead of EGCG may be a promising food supplement for vasospastic diseases.


Asunto(s)
Catequina/análogos & derivados , Miocitos del Músculo Liso , , Ratas , Animales , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/metabolismo , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacología , Vasodilatación , Vasos Coronarios , Arterias Mesentéricas , Vasoconstrictores/farmacología , Agua/farmacología
12.
Sci Rep ; 14(1): 2154, 2024 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-38273013

RESUMEN

Few research discuss whether the body measurement indexs of obesity in general populations is applicable to patients with type 2 diabetes. We explore the optimal cutoffs of visceral fat area (VFA) and subcutaneous fat area (SFA) in the diagnosis of central obesity and the cutoffs of corresponding waist circumference (WC) and body mass index (BMI) in patients with Type 2 Diabetes (T2D). Cross-sectional cohort study. 1057 patients with T2D (550 males and 507 females) aged 18 or above that satisfied the criteria were included. The definition and diagnostic criteria of Metabolic syndrome (Mets) were analyzed according to the 2020 Chinese Diabetes Society (CDS) Guideline. The VFA and SFA were measured by bioelectrical impedance analysis (BIA). The optimal VFA and SFA cutoffs and corresponding WC and BMI when two or more nonadipose components of MetS (without central obesity) were met were analyzed by ROC curve. Among all of the T2D patients, the optimal VFA cutoff for identifying two or more nonadipose components of MetS was 73.30 cm2 for females and 69.20 cm2 for males, while the optimal SFA cutoff was 186.70 cm2 for females and 123.30 cm2 for males. The ROC area under curve (AUC) of VFA for identifying two or more nonadipose components of MetS was higher than that of SFA (Female: 0.65 vs. 0.58, P = 0.01). The VFA cutoff of newly diagnosed T2D patients (females = 86.10 cm2, males = 69.00 cm2) was higher than that of non-newly diagnosed T2D patients (females = 73.30 cm2, males = 65.40 cm2). A stratification analysis of gender and whether newly diagnosed with T2D or not showed that the WCs corresponding to VFA were 85.00 cm and BMI was about 24.00 kg/m2. VFA measured by BIA can be a non-invasive method to detect central obesity in patients with T2D, the corresponding WC were 85.00 cm and BMI was 24.00 kg/m2.


Asunto(s)
Diabetes Mellitus Tipo 2 , Síndrome Metabólico , Masculino , Humanos , Femenino , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/metabolismo , Obesidad Abdominal/complicaciones , Obesidad Abdominal/diagnóstico , Obesidad Abdominal/metabolismo , Estudios Transversales , Obesidad/metabolismo , Síndrome Metabólico/complicaciones , Síndrome Metabólico/diagnóstico , Síndrome Metabólico/metabolismo , Índice de Masa Corporal , Grasa Intraabdominal/metabolismo , Circunferencia de la Cintura , Factores de Riesgo
13.
ACS Appl Mater Interfaces ; 16(32): 42577-42587, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39099305

RESUMEN

As a two-dimensional (2D) material, palladium diselenide (PdSe2) has attracted extensive research attention due to its unique asymmetric crystal structure and extraordinary optoelectronic properties, showing great potential in electronic, optoelectronic, and other application fields. Thinner PdSe2 exhibits semiconductor properties, while the photoresponse of the photodetectors based on this film is weaker. Although increasing the thickness of the PdSe2 film can improve the photoresponse, thicker PdSe2 exhibits metallic-like properties, which is not conducive to the formation of the heterojunction. In this work, a PdSe2 2D material with a quantum island structure is prepared by a simple thermal-assisted conversion method. A new type of photodetector with a PdSe2/n--Si/n+-Si vertical PIN-like structure is innovatively proposed. Broad spectral absorption from 532 to 2200 nm and a high rectification ratio (106) of the device are achieved. The introduced n--Si layer concentrates the electric field in the depletion region, thereby shortening the transit time and accelerating the separation and collection of the carriers, resulting in the enhancement of the responsivity and 3 dB frequency compared to the traditional device with a PN structure. A recorded highest 3 dB frequency of ∼25 kHz is achieved for the PdSe2 2D-3D PIN-like device.

14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(11): 3028-31, 2013 Nov.
Artículo en Zh | MEDLINE | ID: mdl-24555374

RESUMEN

Fourier transform infrared (FTIR) microspectroscopy technology is the combination of the FTIR spectrometer and the microscope. This technology is of simple preparation of the samples, can be used in micro-area analysis and micro-samples, and reflect the nature of the samples spectra. Panax ginseng include mountain cultivated ginseng (MCG), garden cultivated ginseng (GCG) and mountain wild ginseng (MWG), but the excavation of MWG is prohibited in China. So, only MCG and GCG were collected and recorded in Chinese pharmacopoeia. In this study, we developed a discriminant analysis (DA) method for recognition of MCG and GCG using FTIR microspectroscopy technology. Twenty MCG samples and twenty four GCG samples were obtained, and their spectra of IR microspectroscopy were collected. Then 33 samples were randomly selected into calibration set and the remaining 11 of the samples were selected into validation set. The authors optimized the pretreatment method, the principal components, the modeling region and the scanning parts when developing the models. The optimized model of discriminant analysis was developed using the pretreatment multiplicative scatter correction (MSC) + Savitzky-Golay filter (SG) smoothing, the region 3 932.14-669.18 cm(-1), 4 principal components and the rhizome part. The accuracy of the optimized model got up to 100%. The result demonstrated that infrared microspectroscopy technology combined with DA is of simple operation, rapid, nondestructive and effective, and can be applied to recognize MCG and GCG.


Asunto(s)
Panax/clasificación , Espectroscopía Infrarroja por Transformada de Fourier , China , Análisis Discriminante
15.
Fitoterapia ; 169: 105616, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37479119

RESUMEN

Glutamate-induced oxidative stress is well-known to play a crucial role in the development of neurodegenerative diseases, such as stroke. Genipin, a natural iridoid compound, has demonstrated potential neuroprotective properties but is unstable in physiological conditions. The present study aimed to develop new derivatives of genipin that exhibit improved stability and activity for the treatment of stroke. Nineteen new derivatives were thus designed and synthesized. Their neuroprotective effect against glutamate-induced injury was evaluated in HT22 cells. Among the newly synthesized derivatives, 3e demonstrated significantly greater neuroprotection and improved stability compared to genipin. Specifically, 0.01 µM of 3e was found to effectively attenuate glutamate-induced oxidative damage by inhibiting ROS over-accumulation, reducing MDA content, and restoring the endogenous antioxidative system. Further investigation revealed that 3e inhibited oxidative stress by downregulating the phosphorylation levels of p38 MAPK and activating Nrf2 and HO-1 proteins. These results suggested that 3e has the potential to serve as a promising candidate for the treatment of stroke by protecting against glutamate-induced oxidative stress.


Asunto(s)
Ácido Glutámico , Fármacos Neuroprotectores , Ácido Glutámico/toxicidad , Ácido Glutámico/metabolismo , Fármacos Neuroprotectores/farmacología , Línea Celular , Estructura Molecular , Estrés Oxidativo , Iridoides/farmacología , Especies Reactivas de Oxígeno/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo
16.
RSC Adv ; 13(9): 5667-5673, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36816088

RESUMEN

In this paper, betaine (Bet) was used as a hydrogen bond acceptor (HBA), and acrylic acid (AA) and acrylamide (AM) were used as hydrogen bond donors (HBD) and mixed to form a deep eutectic solvent (DES). Different concentrations of ß-cyclodextrin (ß-CD) were dispersed in the DES, and a novel ß-CD/P(AA-co-AM) hydrogel was prepared by frontal polymerization (FP). The characteristic structure and morphology of the hydrogels were analyzed using Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM), and the properties of the hydrogels were investigated. The results show that the mechanical properties of the hydrogel were improved by ß-CD acting as a second cross-linking agent in the polymerization process, thus increasing the cross-link density of the hydrogel. Because the carboxyl groups contained in the acrylic acid dissociate under alkaline conditions, the composite hydrogel shows excellent pH responsiveness under alkaline conditions. Tetracycline hydrochloride was used as a drug model to test the drug loading and drug release performance of the hydrogels. With the increase of ß-CD content, the loading capacity of the hydrogels for tetracycline hydrochloride gradually increased. The data of drug release indicated that the hydrogel has good drug delivery performance and has promising applications in drug delivery systems and other areas.

17.
Front Immunol ; 13: 1071360, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36685548

RESUMEN

As modern medicine began to emerge at the turn of the 20th century, glycan-based therapies advanced. DNA- and protein-centered therapies became widely available. The research and development of structurally defined carbohydrates have led to new tools and methods that have sparked interest in the therapeutic applications of glycans. One of the latest omics disciplines to emerge in the contemporary post-genomics age is glycomics. In addition, to providing hope for patients and people with different health conditions through a deeper understanding of the mechanisms of common complex diseases, this new specialty in system sciences has much to offer to communities involved in the development of diagnostics and therapeutics in medicine and life sciences.This review focuses on recent developments that have pushed glycan-based therapies into the spotlight in medicine and the technologies powering these initiatives, which we can take as the most significant success of the 21st century.


Asunto(s)
Carbohidratos , Glicómica , Humanos , Polisacáridos , Genómica , Proteínas
18.
RSC Adv ; 12(20): 12871-12877, 2022 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-35496327

RESUMEN

A deep eutectic solvent (DES) was synthesized from urea (U), acrylamide (AM), and choline chloride (ChCl). ZnO was dispersed in the DES as a filler, and nanocomposite hydrogels (ZnO/P(U-AM-ChCl)) were successfully prepared by frontal polymerization (FP). The hydrogels were verified by Fourier infrared spectroscopy to contain ZnO nanoparticles (ZnO-NPs). The swelling behaviour, conductivity, and antibacterial properties of the ZnO nanocomposite hydrogels were investigated. The results showed that the ZnO/P(U-AM-ChCl) hydrogels had excellent antibacterial properties and exhibited super high inhibition rates of 81.87% and 88.42% against two basic colonies of Gram-negative and Gram-positive bacteria, respectively. The equilibrium swelling of the hydrogels was found to increase significantly from 9.30 to 12.29 with the addition of ZnO, while the ZnO/P(U-AM-ChCl) hydrogel conductivity exhibited good UV sensitivity. This study provides a rapid and low-energy method for the preparation of nanocomposite hydrogels with excellent antibacterial properties.

19.
RSC Adv ; 12(30): 19022-19028, 2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35865608

RESUMEN

Deep eutectic solvent (DES) was prepared by using acrylic acid (AA) and acrylamide (AM) as hydrogen bonding donors (HBD) and choline chloride (ChCl) as hydrogen bonding receptors (HBA). Nitrogen-doped carbon nanotubes (N-CNTs) were dispersed in DES as fillers, and N-CNTs/P(AA-co-AM) composite hydrogels were prepared by FP. The interaction mode between the hydrogel and N-CNTs was characterized by Fourier infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The mechanical properties, pH response and electrical conductivity of the composite hydrogels were studied. The results showed that the mechanical properties of the hydrogel were significantly enhanced with the increase of N-CNT content. The tensile strength and compressive strength of the FP4 composite hydrogel reached 5.42 MPa and 4.29 MPa, respectively. Due to the dissociation of carboxyl groups in AA in an alkaline environment the composite hydrogel showed excellent pH response performance. The conductivity of the hydrogel was also found to be improved with the content of N-CNTs. When the content of N-CNTs is 1.0 wt%, the conductivity of the hydrogel was 4.2 times higher than that of the hydrogel without N-CNTs, and connecting it to a circuit can make an LED lamp emit bright light. In this study, a simple and green method was proposed to prepare composite hydrogels with excellent mechanical properties and electrical conductivity by FP of DES in less than 5 min.

20.
ChemMedChem ; 17(4): e202100659, 2022 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-34881517

RESUMEN

A series of mitochondria-targeted triphenylphosphonium conjugated C-3 modified betulin were synthesized and evaluated against tumor cells. As a result, a new derivative 13 i, the conjugate of 3-O-(3'-acetylphenylacetate)-betulin with triphenylphosphonium, was identified as the one with the best anti-tumor effect. Conjugate 13 i significantly inhibited HCT116 cells with IC50 at 0.66 µM. While betulin, C-3 modified betulin, and the triphenylphosphonium moiety showed no inhibition of HCT116 cell proliferation at 20 µM. More importantly, 13 i exhibited a more cytotoxic effect against the tumor cell HCT116 than normal cell NCM460. Mode of action studies demonstrated that 13 i induced the G2/M phase cell cycle arrest and apoptosis in HCT116 cells through the mitochondrial pathway. Structure-activity relationship analysis revealed that integration of triphenylphosphonium moiety into the C-28 of betulin can greatly improve cytotoxicity. Appropriate modification on C-3 of the conjugate would improve the selectivity.


Asunto(s)
Antineoplásicos/farmacología , Mitocondrias/efectos de los fármacos , Compuestos Organofosforados/farmacología , Triterpenos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Mitocondrias/metabolismo , Estructura Molecular , Compuestos Organofosforados/química , Relación Estructura-Actividad , Triterpenos/química
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