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1.
Molecules ; 29(7)2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38611956

RESUMEN

The rational design of covalent organic frameworks (COFs) with hydrochromic properties is of significant value because of the facile and rapid detection of water in diverse fields. In this report, we present a thiazole-linked COF (TZ-COF-6) sensor with a large surface area, ultrahigh stability, and excellent crystallinity. The sensor was synthesized through a simple three-component reaction involving amine, aldehyde, and sulfur. The thiazole and methoxy groups confer strong basicity to TZ-COF-6 at the nitrogen sites, making them easily protonated reversibly by water. Therefore, TZ-COF-6 displayed color change visible to the naked eye from yellow to red when protonated, along with a red shift in absorption in the ultraviolet-visible diffuse reflectance spectra (UV-vis DRS) when exposed to water. Importantly, the water-sensing process was not affected by polar organic solvents, demonstrating greater selectivity and sensitivity compared to other COF sensors. Therefore, TZ-COF-6 was used to detect trace amounts of water in organic solvents. In strong polar solvents, such as N,N-dimethyl formamide (DMF) and ethanol (EtOH), the limit of detection (LOD) for water was as low as 0.06% and 0.53%, respectively. Even after 8 months of storage and 15 cycles, TZ-COF-6 retained its original crystallinity and detection efficiency, displaying high stability and excellent cycle performance.

2.
Bioorg Med Chem ; 80: 117172, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36709570

RESUMEN

Chitinases are important glycoside hydrolases that are closely related to bacterial pathogenesis, fungal cell wall remodelling, and insect moulting. Consequently, chitinases have become attractive targets for therapeutic drugs and pesticides. In this study, we designed and synthesised a series of novel chitinase inhibitors based on the N-methylcarbamoylguanidinyl group of the natural product argifin. The most active compound 8h showed strong inhibitory activity against the group I chitinases HsChit1, SmChiB, and OfChi-h, with IC50 values of 0.19 µM, 4.2 nM, and 25 nM, respectively. Binding mode studies revealed that the compound 8h formed π-π stacking/hydrophobic interactions at +1 or +2 subsite of chitinases. In addition, a key hydrogen bond net was formed between the pharmacophore N-methylcarbamoylguanidinyl and key residues at the -1 subsite. Together, the findings of this study provide novel insights into the development of potent small-molecule chitinase inhibitors using a combination of planar structures and N-methylcarbamoylguanidinyl.


Asunto(s)
Quitinasas , Inhibidores Enzimáticos , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Quitinasas/química , Quitinasas/metabolismo
3.
J Am Acad Dermatol ; 88(6): 1300-1307, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36806645

RESUMEN

BACKGROUND: Patients with refractory erythema of rosacea have limited treatment options. OBJECTIVE: To evaluate the efficacy and safety of a 12-week course of paroxetine for moderate-to-severe erythema of rosacea. METHODS: In a multicenter, randomized, double-blinded, placebo-controlled trial, patients with refractory erythema of rosacea were randomly assigned (1:1) to receive paroxetine 25 mg daily or placebo for 12 weeks. RESULTS: Overall, 97 patients completed the study (paroxetine: 49; placebo: 48). The primary end point was the proportion of participants achieving Clinical Erythema Assessment success (defined as Clinical Erythema Assessment score of 0, 1, or ≥2-grade improvement from baseline) at week 12; this was significantly greater in the paroxetine group than in the placebo group (42.9% vs 20.8%, P = .02). Some secondary end points were met, such as flushing success with point reductions ≥2 (44.9% vs 25.0%, P = .04) and improvement in overall flushing (2.49 ± 3.03 vs 1.68 ± 2.27, P = .047), burning sensation (46.9% vs 18.8%, P = .003), and depression (P = .041). The most reported adverse events associated with paroxetine were dizziness, lethargy, nausea, dyspepsia, and muscle tremors. LIMITATIONS: Only a single-dosage regimen of paroxetine within a 12-week study was evaluated. CONCLUSIONS: Paroxetine is an effective and well-tolerated alternative treatment for moderate-to-severe erythema of rosacea.


Asunto(s)
Paroxetina , Rosácea , Humanos , Paroxetina/uso terapéutico , Estudios Prospectivos , Rosácea/complicaciones , Rosácea/tratamiento farmacológico , Eritema/tratamiento farmacológico , Eritema/etiología , Resultado del Tratamiento , Método Doble Ciego
4.
J Eur Acad Dermatol Venereol ; 37(4): 796-809, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36367676

RESUMEN

BACKGROUND: Rosacea is a chronic inflammatory skin disease with increased macrophage infiltration. However, the molecular mechanism remains unclear. OBJECTIVES: To determine the significance of macrophage infiltration, and the correlation between Guanylate-binding protein 5 (GBP5) and polarization of macrophages in rosacea-like inflammation. METHODS: Here we tested the hypothesis that Guanylate-binding protein 5 (GBP5) aggravates rosacea-like skin inflammation by promoting the polarization of the M1 macrophages through the NF-κB signalling pathway. We depleted macrophage by injecting clodronate-containing liposomes. We next explored the association between GBP5 and macrophage in rosacea tissue through transcriptome analysis and immunofluorescence analysis. We evaluated the severity of rosacea-like skin inflammation when BALB/c mice were injected with GBP5 siRNA intradermally daily for three consecutive days. At last, to study the causality of knocking down GBP5-blunted M1 macrophage polarization, THP-1 cell was treated with GBP5 siRNA. RESULTS: Macrophage depletion ameliorated rosacea-like skin inflammation in mice, implying the important role of macrophages in rosacea. Based on the transcriptome analysis, Guanylate-binding protein 5 (GBP5) was identified as hub gene that was associated with macrophage infiltration in rosacea. Next, we found that GBP5 expression was significantly upregulated in rosacea tissues and positively correlated with macrophage infiltration, the immunofluorescence analysis revealed the co-localization between GBP5 and macrophages. In vivo, silencing of GBP5 attenuated rosacea-like skin inflammation in the LL-37-induced mouse model and suppressed the expression of M1 signature genes such as IL-6, iNOS and TNF-a. In vitro, knocking down GBP5 significantly blunted the polarization of the M1 macrophages partly by repressing the activation of the NF-κB signalling pathways. CONCLUSIONS: Together, our study revealed the important role of macrophages in rosacea and identified GBP5 as a key regulator of rosacea by inducing M1 macrophage polarization via NF-κB signalling pathways.


Asunto(s)
Proteínas de Unión al GTP , FN-kappa B , Rosácea , Animales , Ratones , Dermatitis/genética , Dermatitis/metabolismo , Proteínas de Unión al GTP/genética , Proteínas de Unión al GTP/metabolismo , Inflamación , Macrófagos/metabolismo , FN-kappa B/metabolismo , Fenotipo , ARN Interferente Pequeño , Rosácea/genética , Rosácea/metabolismo
5.
Hereditas ; 160(1): 11, 2023 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-36907956

RESUMEN

BACKGROUND: Acid sphingomyelinase deficiency (ASMD) disorder, also known as Niemann-Pick disease (NPD) is a rare genetic disease caused by mutations in SMPD1 gene, which encodes sphingomyelin phosphodiesterase (ASM). Except for liver and spleen enlargement and lung disease, two subtypes (Type A and B) of NDP have different onset times, survival times, ASM activities, and neurological abnormalities. To comprehensively explore NPD's genotype-phenotype association and pathophysiological characteristics, we collected 144 NPD cases with strict quality control through literature mining. RESULTS: The difference in ASM activity can differentiate NPD type A from other subtypes, with the ratio of ASM activity to the reference values being lower in type A (threshold 0.045 (4.45%)). Severe variations, such as deletion and insertion, can cause complete loss of ASM function, leading to type A, whereas relatively mild missense mutations generally result in type B. Among reported mutations, the p.Arg3AlafsX76 mutation is highly prevalent in the Chinese population, and the p.R608del mutation is common in Mediterranean countries. The expression profiles of SMPD1 from GTEx and single-cell RNA sequencing data of multiple fetal tissues showed that high expressions of SMPD1 can be observed in the liver, spleen, and brain tissues of adults and hepatoblasts, hematopoietic stem cells, STC2_TLX1-positive cells, mesothelial cells of the spleen, vascular endothelial cells of the cerebellum and the cerebrum of fetuses, indicating that SMPD1 dysfunction is highly likely to have a significant effect on the function of those cell types during development and the clinicians need pay attention to these organs or tissues as well during diagnosis. In addition, we also predicted 21 new pathogenic mutations in the SMPD1 gene that potentially cause the NPD, signifying that more rare cases will be detected with those mutations in SMPD1. Finally, we also analysed the function of the NPD type A cells following the extracellular milieu. CONCLUSIONS: Our study is the first to elucidate the effects of SMPD1 mutation on cell types and at the tissue level, which provides new insights into the genotype-phenotype association and can help in the precise diagnosis of NPD.


Asunto(s)
Enfermedad de Niemann-Pick Tipo A , Enfermedades de Niemann-Pick , Esfingomielina Fosfodiesterasa , Humanos , Células Endoteliales/metabolismo , Células Endoteliales/patología , Estudios de Asociación Genética , Mutación , Enfermedad de Niemann-Pick Tipo A/diagnóstico , Enfermedad de Niemann-Pick Tipo A/genética , Enfermedad de Niemann-Pick Tipo A/patología , Enfermedades de Niemann-Pick/diagnóstico , Enfermedades de Niemann-Pick/genética , Esfingomielina Fosfodiesterasa/genética , Esfingomielina Fosfodiesterasa/metabolismo
6.
Plant Dis ; 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38085241

RESUMEN

Cowpea (Vigna unguiculata L.), a significant vegetable crop in China, holds particular prominence in the tropical island of Hainan. This region serves as the primary production area for the winter cultivation of cowpea. Phytoplasmas are an idiopathic parasitic pathogen and cannot be cultured in vitro. It is mainly transmitted by the insect vectors with the piercing and sucking mouthparts, such as leafhoppers, plant hoppers, and psyllids. (Kumari et al. 2019). On September 11, 2023, typical characteristics of phytoplasma diseases on cowpeas were observed in the experimental base of Hainan Academy of Agricultural Sciences (20°0'38.6964″N, 110°21'35.4024″E, Haikou City, Hainan Province, China), including reduced leaf size, chlorosis, and the development of broom-like branch deformities reminiscent, as depicted in Figure 1. At the same time, we found a large number of leafhoppers near the diseased plants, and we speculated that leafhoppers are the insect carriers that spread the disease. Following an on-site investigation, it was determined that the disease incidence ranges from 10% to 15%, leading to a consequential decrease of about 10% in yield, which is a potential disease that seriously threatens the cowpea industry in Hainan. Ten disease and healthy samples were meticulously collected and subsequently preserved at -80°C within the laboratory refrigerator. Three disease samples denoted as HNNKY-1, HNNKY-2, and HNNKY-3, were randomly chosen, and total DNA extraction was carried out employing the NuClean Plant Genomic DNA Kit (CWBIO, Taizhou, China), while three healthy samples were randomly selected as control. The 16S rRNA gene was amplified by PCR using the primer pairs P1/P7 (Schneider et al. 1995) and R16F2n / R16R2 (Lee et al. 1993) and the secA gene was amplified by PCR using the primer pairs secAfor1/secArev3 (Hodgetts et al. 2008). After agarose gel electrophoresis analysis, no DNA fragments were observed in the healthy leaf samples, whereas all three disease samples yielded amplification products. The PCR products were subsequently sequenced by Hainan Nanshan Biotech Co., Ltd., Haikou, China. After sequence analysis, it was found that the 16S rRNA gene and secA gene sequences HNNKY-1, HNNKY-2, and HNNKY-3 were identical to each other. We selected two gene sequences of strain HNNKY-3 to submission to the GenBank database, The length of the 16S rRNA gene sequence is 1193 base pairs, identified by the accession number OR666421, while the secA gene sequence is 825 base pairs in length, associated with the accession number OR661282. The phytoplasma strain HNNKY-3 was named 'Vigna unguiculata' witches'-broom phytoplasma. A BLAST analysis of the 16S rRNA gene revealed that strain HNNKY-3 displayed a 100% sequence match with 'Emilia sonchifolia' witches'-broom phytoplasma (MT420682), Peanut witches'-broom phytoplasma (OR239773), and 'Raphanus sativus' witches'-broom phytoplasma (OK491387). All of these phytoplasmas were classified within the 16SrII group. Based on the BLAST analysis of partial secA gene sequences, it was discerned that sequence homogeneity ranged from 99.27% to 99.74% among the studied sequences. These sequences were collectively classified as members of the 16SrII group. In addition, a phylogenetic tree was constructed by MEGA 11 (version 11.0.13) based on the 16Sr RNA gene and secA gene by the neighbor-joining method (Tamura et al. 2004). The results demonstrated the clustering of HNNKY-3 phytoplasma strains within the 16SrII group, as illustrated in Figures 2 and 3. A virtual RFLP analysis based on the 16S rRNA gene fragment of HNNKY-3 was conducted using the interactive online phytoplasma classification tool, iPhyClassifier (Zhao et al. 2009). The results indicated that the phytoplasma strain was the same as the reference pattern of the onion yellows phytoplasma of 16SrII-A (GenBank accession: L33765), and the similarity coefficient was 1.00. To best of our knowledge, this is the inaugural documentation of 16SrII Group-related phytoplasma infecting cowpea in Hainan, China, and lays the groundwork for further research on the dissemination of cowpea phytoplasma disease within China.

7.
BMC Med Educ ; 23(1): 195, 2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-36991459

RESUMEN

BACKGROUND: The global spread of Coronavirus disease (COVID-19) has led to the use of online teaching methods in universities, but the effect of online education on dermatology teaching remains unclear. METHODS: We designed a multi-dimensional teaching evaluation form for data collection, student teaching feedback evaluation, and assessed the scores of final theoretical and clinical skill tests, to compare the effective difference between online and offline teaching of dermatology. RESULTS: A total of 311 valid questionnaires of medical undergraduates were collected, 116 of which were enrolled for offline learning, and 195 for online learning. The average score of final theoretical test in the online teaching group had no significant difference compared with that in the offline teaching group (75.33 ± 7.37 vs.75.63 ± 7.51, P = 0.734). However, both scores of skin lesion recognition test and medical history collection test in the online teaching group were significantly lower than that in the offline teaching group (6.53 ± 0.86 vs. 7.10 ± 1.11, P < 0.001; 6.70 ± 1.16 vs. 7.62 ± 0.85, P < 0.001). Additionally, the scores of understanding skin lesions in the online teaching group were significantly lower than that in the offline group (P < 0.001), and the scores of overall understanding of skin diseases and evaluating their learning mode in the online teaching group also decreased (P < 0.05). Among the 195 students enrolled in the online learning group, 156 students (80.0%) recognized that the time of offline teaching should be increased. CONCLUSIONS: Both online and offline education can be used in dermatology theory teaching, but online education is less efficient in skin lesion and practical skills learning. More online teaching software with skin diseases characteristic should be developed to improve the online teaching effect.


Asunto(s)
COVID-19 , Dermatología , Educación a Distancia , Estudiantes de Medicina , Humanos , Estudios Transversales , Dermatología/educación , Hospitales de Enseñanza , Pandemias , China
8.
Plant Dis ; 2022 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-36089690

RESUMEN

Alpinia oxyphylla Miq. is mainly distributed in Hainan, Guangdong and Guangxi provinces of China. Between July and August 2021, a leaf spot disease was observed in Ledong, Hainan Province, China (18°70'20.50″ N, 109°25'25.47″E) on A.oxyphylla. The incidence of infected leaves ranged from 8% to 10%, and the incidence rate of infected plants was about 50%. Symptoms appeared as primary yellow-brown withered spots on the diseased leaves, which further developed into irregular red-brown spots. The center of the lesions was gray-black, and the tissue was irregularly necrotic, ruptured or perforated, and there were yellow chlorotic halos around the edges of the lesions (Figure 1A). Tissues 5 mm in diameter were taken from the junction of diseased and healthy tissue for pathogen isolation, Successively, a total of 8 isolates were obtained from the affected leaves. Three single spore isolates (YZ-HN-001, YZ-HN-043 and YZ-HN-051) were obtained and confirmed to be identical based on morphological characteristics. Therefore, the representative isolate YZ-HN-001 was selected for morphological and molecular identification. On Potato Dextrose Agar(PDA), the colony was gray-white at first and gradually turned dark green to dark brown with lead gray on the back, growth was slow, and mycelium was short and dense (Figure 1B and Figure 1C). Pycnidia were epiphyllous, globose, brown (about 120-140 µm in diameter), and conidia were elliptical, colorless, single celled and smooth (8-12×4-7 µm) (Figure 1D). Molecular identification was performed by partially sequencing the internal transcribed spacer gene (ITS), 18S rRNA gene and the actin gene (ACT) by using the primers ITS1/ITS4 (White et al. 1990), EF4/Fungi5 (Khodaparase et al. 2005) and ACT-512F/ACT-783R (Carbone and Kohn. 1999). The sequences of the amplified fragments were deposited in GenBank, the ITS sequence (ON005130, 616 bp) showed 100% identity with Phyllosticta capitalensis strain CGMCC3.14345 (JN791605.1), the 18S rRNA sequence (ON005129, 541 bp) showed 99% identity with P. capitalensis isolate MUCC0029 (AB454185.1) and the ACT sequence (ON049348, 251 bp) showed 100% identity with P. capitalensis strain DZSN202005-2 (MW533248.1). A phylogenetic analysis was conducted in MEGA X using the neighbor-joining method and showed that isolate YZ-HN-001 clustered together with P. capitalensis (Figure 2). Based on the above morphological and molecular characteristics, the isolate was determined to be P. capitalensis. Pathogenicity tests were conducted in three replicates by inoculating surface-sterilized leaves of A. oxyphylla. The leaves were wounded and inoculated with colonized PDA plugs (5×5 mm) from 15-day-old cultures. Control leaves wounded in the same way and were inoculated with sterile PDA plugs (5×5 mm). Leaves were moisturized by spraying with sterile water every three days. After 20 days at room temperature (23 to 28℃), similar symptoms were observed in the inoculated leaves as in the field (Figure 1E), but no symptoms were observed on the control leaves (Figure 1F). The same P. capitalensis was reisolated in the inoculated leaves, confirming Koch's postulates. Phyllosticta capitalensis has been reported to cause leaf spots or black spots on various host plants around the world (Wikee et al. 2013), including on oil palm (Nasehi et al. 2020), tea plant (Cheng et al. 2019 ), and castor (Tang et al. 2020). Nevertheless, to our knowledge, this is the first report of leaf spot caused by P. capitalensis on A. oxyphylla worldwide.

9.
Langmuir ; 37(20): 6158-6167, 2021 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-33969992

RESUMEN

Water flow through two-dimensional nanopores has attracted significant attention owing to the promising water purification technology based on atomically thick membranes. However, the theoretical description of water flow in nanopores based on the classical continuum theory is very challenging owing to the pronounced entrance/exit effects. Here, we extend the classical Hagen-Poiseuille equation for describing the relationship between flow rate and pressure loss in laminar tube flow to two-dimensional nanopores. A totally theoretical model is established by appropriately considering the velocity slip on pore surfaces both in the friction pressure loss and entrance/exit pressure loss. Based on molecular dynamics simulations of water flow through graphene nanopores, it is shown that the model can not only well predict the overall flow rate but also give a good estimation of the velocity profiles. As the pore radius and length increase, the model can reduce to the equations applicable to the fluid flow in infinitely/finitely long nanotubes, thin orifices, and macroscale tubes, showing an accurate prediction of the existing experimental and simulation data of the water flow through nanotubes and nanopores in the literature. Namely, the presented model is a unified model that can uniformly describe the fluid flow from nanoscales to macroscales by modifying the classical continuum theory.

10.
Acta Derm Venereol ; 101(6): adv00488, 2021 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-34159391

RESUMEN

The exact mechanisms of rosacea development are unknown, but it has been suggested that tea consumption may be associated with its development. To determine the relationship between tea drinking behaviour and rosacea, this clinical case-control study recruited 2,063 participants, who completed a questionnaire about tea drinking behaviour. A 1:1 ratio propensity score matching method was used to generate 619 cases and 619 controls. High-frequency tea drinking (3 times/day: adjusted odds ratio (aOR) 2.592; 95% confidence interval (95% CI) 1.225-5.485; ≥ 4 times/day; aOR 8.86; 95% CI 3.43-22.887), non-fermented tea (aOR 2.172; 95% CI 1.562-3.022), and hot tea (aOR 2.793; 95% CI 1.796-1.344) were associated with an increased risk of rosacea. Further results showed that these tea drinking behaviours were significantly associated with an increased risk of flushing (aOR 1.41; 95% CI 1.07-1.87) and erythema (aOR 1.48; 95% CI 1.10-2.00). Tea drinking behaviour is closely related to rosacea and.


Asunto(s)
Rosácea , , Estudios de Casos y Controles , Humanos , Oportunidad Relativa , Factores de Riesgo , Rosácea/diagnóstico , Rosácea/epidemiología
11.
Biochem Biophys Res Commun ; 521(1): 64-71, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31627897

RESUMEN

Rosacea is a chronic inflammatory cutaneous disease which mainly affects central face, leading to cosmetic disfigurement and compromised social psychology in billions of rosacea patients. Though the exact etiology of rosacea remains elusive, accumulating evidence has highlighted the dysfunction of innate immunity and inflammation in rosacea pathogenesis. Disintegrin Metalloprotease ADAM-like Decysin-1 (ADAMDEC1) is an orphan ADAM-like metalloprotease which is believed to be closely related to inflammation. Here for the first time, we reported that Adamdec1 expression was significantly increased in the skin lesions of rosacea patients and LL37-induced rosacea-like mouse models. Immunofluorescence analysis revealed co-localization of ADAMDEC1 and macrophages in patient and mouse biopsies. In cellular experiment, the expression of ADAMDEC1 was prominently elevated in M1 but not M2 macrophages. Knocking down of ADAMDEC1 significantly blunted M1 polarization in macrophages induced from human monocytes and THP-1 cell lines. Furthermore, silencing of Adamdec1 in LL-37-induced mouse model also suppressed the expression of M1 signature genes such as IL-6, iNOS and TNF-α, resulting in attenuated rosacea-like phenotype and inflammation. Taken together, our results demonstrate that ADAMDEC1 plays a pro-inflammatory role in rosacea via modulating the M1 polarization of macrophages.


Asunto(s)
Proteínas ADAM/metabolismo , Inflamación/metabolismo , Macrófagos/metabolismo , Rosácea/metabolismo , Piel/metabolismo , Adulto , Femenino , Humanos , Persona de Mediana Edad
12.
J Chem Phys ; 153(23): 234701, 2020 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-33353331

RESUMEN

The structure of nanoconfined fluids is particularly non-uniform owing to the wall interaction, resulting in the distinctive characteristic of thermal transport compared to bulk fluids. We present the molecular simulations on the thermal transport of water confined in nanochannels with a major investigation of its spatial distribution under the effects of wall interaction. The results show that the thermal conductivity of nanoconfined water is inhomogeneous and its layered distribution is very similar to the density profile. The layered thermal conductivity is the coupling result of inhomogeneous density and energy distributions that are generally diametrical, and their contributions to the thermal conductivity compensate with each other. However, the accumulative effect of water molecules is really dominating, resulting in a high thermal conductivity in the high-density layers with the low-energy molecules, and vice versa. Moreover, it is found that the adsorptive and repulsive interactions from solid walls have different roles in the hierarchical thermal transport in nanoconfined water. The adsorptive interaction is only responsible for the layered distribution of thermal conductivity, while the repulsive interaction is responsible for the overall thermal conductivity; accordingly, the thermal conductivity is independent of the strength of water-solid interactions. The identified hierarchical thermal transport in nanoconfined water and its underlying mechanisms have a great significance for the understanding of nanoscale thermal transport and even the mass and energy transport of nanoconfined fluids.

13.
Sensors (Basel) ; 20(8)2020 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-32290511

RESUMEN

This paper presented a non-uniform multiphase (NUMP) time-to-digital converter (TDC) implemented in a field-programmable gate array (FPGA) with real-time automatic temperature compensation. NUMP-TDC is a novel, low-cost, high-performance TDC that has achieved an excellent performance in Altera Cyclone V FPGA. The root mean square (RMS) for the intrinsic timing resolution was 2.3 ps. However, the propagation delays in the delay chain of some FPGAs (for example, the Altera Cyclone 10 LP) vary significantly as the temperature changes. Thus, the timing performances of NUMP-TDCs implemented in those FPGAs are significantly impacted by temperature fluctuations. In this study, a simple method was developed to monitor variations in propagation delays using two registers deployed at both ends of the delay chain and compensate for changes in propagation delay using a look-up table (LUT). When the variations exceeded a certain threshold, the LUT for the delay correction was updated, and a bin-by-bin correction was launched. Using this correction approach, a resolution of 8.8 ps RMS over a wide temperature range (5 °C to 80 °C) had been achieved in a NUMP-TDC implemented in a Cyclone 10 LP FPGA.

14.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(2): 165-168, 2020 Feb 28.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-32386042

RESUMEN

OBJECTIVES: To explore the relationship between the incidence of rosacea and drinking, smoking, gender or age, and to provide some basis for the diagnosis, treatment and mechanism of rosacea. METHODS: A total of 1 180 patients with rosacea and 1 008 non-rosacea patients diagnosed in the Department of Dermatology of Xiangya Hospital were included in the study. Logistic analysis was performed on the incidence factors, and the differences between the two groups in different age groups were compared. RESULTS: There was no significant difference in gender between the two groups (P>0.05). Logistic analysis showed that drinking had no effect on the incidence of rosacea (P>0.05); while smoking, gender, and age had an effect on the incidence of rosacea (P<0.05). The highest proportion of patients with rosacea was 25-34 years old. CONCLUSIONS: The incidence of rosacea has nothing to do with alcohol consumption; while smoking, gender, and age affect the incidence. Smoking and women are the risk factors, and the most common age of rosacea is at 25-34 years old.


Asunto(s)
Consumo de Bebidas Alcohólicas , Rosácea , Adulto , China , Femenino , Humanos , Incidencia , Factores de Riesgo , Rosácea/epidemiología , Fumar
15.
IEEE Trans Instrum Meas ; 68(9): 3200-3210, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31413382

RESUMEN

Reading out from large-scale silicon photomultiplier (SiPM) arrays is a fundamental technical obstacle blocking the application of revolutionary SiPM technologies in nuclear imaging systems. Typically, it requires using dedicated application-specific integrated circuits (ASICs) that need a long iterative process, special expertise, and tools to develop. The pico-positron emission tomography (Pico-PET) electronics system is an advanced 100-channel readout system based on 1-bit sigma-delta modulation and a field-programmable gate array (FPGA). It is compact (6 × 6 × 0.8 cm3 in size), consumes little power (less than 3W), and is constructed with off-the-shelf low-cost components. In experimental studies, the Pico-PET system demonstrates excellent and consistent performance. In addition, it has some unique features that are essential for nuclear imaging systems, such as its ability to measure V-I curves, breakdown voltages, and the dark currents of 100 SiPMs accurately, simultaneously, and in real time. The flexibility afforded by FPGAs allows multiple-channel clustering and intelligent triggering for different detector designs. These highly sought-after features are not offered by any other ASICs and electronics systems developed for nuclear imaging. We conclude that the Pico-PET electronics system provides a practical solution to the long-standing bottleneck problem that has limited the development of potentially advanced nuclear imaging technology using SiPMs.

16.
IEEE Trans Instrum Meas ; 68(10): 3647-3660, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33132409

RESUMEN

We present a nonuniform multiphase (NUMP) method to construct a high-resolution time-to-digital converter (TDC) for low-cost field-programmable gate array (FPGA) devices. The NUMP method involves a system clock being passed through a series of delay elements to generate multiple clocks with different phase shifts. The phases of the rising and falling edges of all the clocks are sorted in order and the states of all the clocks are latched when a hit signal arrives. The sizes of the time bins (and precision) of the NUMP method are not limited by the uniformity and minimum value of the time delays of the delay lines. In theory, any delay sources with small jitters in an FPGA, not just very fine carry chains, can be used in the NUMP method to delay and randomize the clocks. Thus, the NUMP method can achieve excellent TDC timing resolutions in low-cost FPGAs without very fine delay lines. We implemented four NUMP TDC channels in a low-cost FPGA device (an Altera Cyclone V 5CEBA4F23C7N). The performance of the four NUMP TDCs was evaluated using both internal and external pulses. The root mean square (rms) for the timing resolution measured using the internal and the external pulses with short-time intervals (less than 1 ns) was 2.3 and 5.2 ps, respectively. A 14.1-ps rms timing resolution was measured at a time interval of 517 ns. The NUMP method is suitable for applications that require a number of high-performance TDC channels in a low-cost FPGA.

17.
Beilstein J Org Chem ; 15: 2847-2855, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31839830

RESUMEN

A novel anthracene-based tetraperimidine hexafluorophosphate 3 was prepared, and its structure was determined through X-ray analysis, HRMS as well as 1H and 13C NMR spectroscopy. In the cationic moiety of 3, two (N-ethylperimidinyl-C2H4)2NCH2- arms were attached to the 9- and 10-positions of anthracene. In addition, compound 3 was used as a chemosensor to research the ability to recognize Cr3+ through fluorescence and UV titrations, HRMS, as well as 1H NMR and IR spectroscopy. The results indicate that 3 is an effective chemosensor for Cr3+.

18.
J Am Chem Soc ; 140(7): 2478-2484, 2018 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-29406750

RESUMEN

DNA origami is a promising molecular delivery system for a variety of therapeutic applications including cancer therapy, given its capability to fabricate homogeneous nanostructures whose physicochemical properties (size, shape, surface chemistry) can be precisely tailored. However, the correlation between DNA-origami design and internalization efficiency in different cancer cell lines remains elusive. We investigated the cellular uptake of four DNA-origami nanostructures (DONs) with programmed sizes and shapes in multiple human cancer cell lines. The cellular uptake efficiency of DONs was influenced by size, shape, and cell line. Scavenger receptors were responsible for the internalization of DONs into cancer cells. We observed distinct stages of the internalization process of a gold nanoparticle (AuNP)-tagged rod-shape DON, using high-resolution transmission electron microscopy. This study provides detailed understanding of cellular uptake and intracellular trafficking of DONs in cancer cells, and offers new insights for future optimization of DON-based drug delivery systems for cancer treatment.


Asunto(s)
ADN/farmacocinética , Oro/farmacocinética , Nanopartículas del Metal/química , Línea Celular Tumoral , ADN/química , Sistemas de Liberación de Medicamentos , Oro/química , Humanos , Tamaño de la Partícula
19.
Fish Shellfish Immunol ; 77: 200-207, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29574130

RESUMEN

The genetically improved farmed tilapia (GIFT, Oreochromis niloticus) is cultured widely for production of freshwater fish in China, while streptococcosis, likely related to pathogenic infections, occurs frequently in juvenile, mother, and operated GIFT. The gut microbiota plays an important role in nutrient digestibility in animals, and resveratrol (RES) has been used in feed for different freshwater fish species. Therefore, understanding changes in the tilapia gut microbiota across different concentrations of dietary RES supplementation is extremely important. The gut microbiota population in tilapia at 45 d after supplementation with different concentrations (0, 0.025, 0.05, 0.1 g/kg) of dietary RES was assessed by 16S rDNA gene sequencing. A total of 5445 operational taxonomic units were identified from all samples, and 14 phyla and 81 families were identified from all fecal samples. The bacteria of the phylum Firmicutes were significantly enriched in the 0.025 g/kg RES group when compared with the controls. Proteobacteria, Firmicutes and Cyanobacteria were the most dominant three phyla in all samples. With the increasing concentrations, the proportion of beneficial microbial taxa (Acetobacteraceae and Methylobacteriaceae) increased, whereas the proportion of harmful microbial taxa decreased, eg. Streptococcaceae except for 0.1 g/kg RES groups. RES did not affect the richness and diversity in tilapia gut microbiota. These findings provide information on the diversity and differences in GIFT gut microbiota database, and may contribute to developing strategies for management of diseases and long-term sustainability of O. niloticus culture.


Asunto(s)
Cíclidos/fisiología , Microbioma Gastrointestinal/efectos de los fármacos , Estilbenos/metabolismo , Alimentación Animal/análisis , Animales , Cíclidos/microbiología , Dieta/veterinaria , Suplementos Dietéticos/análisis , Relación Dosis-Respuesta a Droga , Masculino , Distribución Aleatoria , Resveratrol , Estilbenos/efectos adversos
20.
Ecotoxicol Environ Saf ; 147: 447-454, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28892663

RESUMEN

The GIFT (Genetically Improved Farmed Tilapia) tilapia, Oreochromis niloticus, is cultured widely for the production of freshwater fish in China. Streptococcosis, which is related to pathogenic infections, occurs frequently in juvenile and adult female GIFT individuals. Resveratrol (RES) has been used in feed to control these infections in freshwater tilapia. To address the effects of RES on tilapia, we used high-throughput RNA sequencing technology (RNA-Seq, HiSeq. 2500) to explore the global transcriptomic response and specific involvement of hepatic mRNA of juvenile O. niloticus fed with diets containing different concentrations of (0, 0.025, 0.05, and 0.1g/kg) RES. A total of > 24,513,018 clean reads were generated and then assembled into 23,244 unigenes. The unigenes were annotated by comparing them against non-redundant protein sequence (Nr), non-redundant nucleotide (Nt), Swiss-Prot, Pfam, Gene Ontology database (GO), Clusters of Orthologous Groups (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, and 12,578 unigenes were annotated to the GO database. A total of 1444 (0.025g/kg RES), 1526 (0.05g/kg RES), and 3135 (0.1g/kg RES) genes were detected as significant differentially expressed genes (DEGs), when compared with the controls. A total of 6 (0.025 vs 0.05g/kg RES), 19 (0.025 vs 0.1g/kg RES), and 124 (0.05 vs 0.1g/kg RES) genes were detected as significant DEGs. Six genes, including dnah7x1, sox4, fam46a, hsp90a, ddit4, and nmrk2, were associated with an immune response. These findings provide information on the innate immunity of GIFT and might contribute to the development of strategies for the effective management of diseases and long-term sustainability of O. niloticus culture.


Asunto(s)
Cíclidos/metabolismo , Hígado/efectos de los fármacos , Estilbenos/farmacología , Transcriptoma/efectos de los fármacos , Animales , China , Cíclidos/inmunología , Dieta , Suplementos Dietéticos , Relación Dosis-Respuesta a Droga , Perfilación de la Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento , Inmunidad Innata/efectos de los fármacos , Hígado/metabolismo , Resveratrol
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