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1.
Anal Chem ; 96(35): 14230-14238, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39172624

RESUMEN

Activatable photosensitizers (PSs) generating 1O2 only under specific conditions can minimize concomitant injury to normal tissues. Heavy-atom-free PSs hold the merits of low dark toxicity, long triplet-state lifetimes, good photostability, and relatively low cost. PSs with emission in the second near-infrared (NIR-II) window are highly valuable for deep-tissue, high-contrast imaging. Herein, we have designed and synthesized a series of heavy-atom-free PSs by a one-step reaction between an easily accessible rhodamine derivative and commercially available thiophene aldehydes. One of the as-prepared PSs, 2b-3T, exhibits emission maxima at 810 nm and tails to the NIR-II region at 1140 nm, together with large Stokes shift (178 nm). Importantly, the newly developed PSs, featuring functional carboxylic acid groups, present promising opportunities as versatile platforms for creating activatable PSs. To validate our concept, we developed Cu2+/pH-activatable PSs using the spirocyclization mechanism of rhodamine. Ultimately, we showcased the effectiveness of these innovative PSs in photodynamic therapy through in vitro experiments.


Asunto(s)
Rayos Infrarrojos , Fármacos Fotosensibilizantes , Rodaminas , Fármacos Fotosensibilizantes/química , Rodaminas/química , Humanos , Fotoquimioterapia , Estructura Molecular , Supervivencia Celular/efectos de los fármacos , Células HeLa , Cobre/química
2.
J Acoust Soc Am ; 155(4): 2561-2576, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38597732

RESUMEN

A study is presented of the thermal-mechanical noise and response to sound of microphones that are designed to be driven by the viscous forces in air rather than by sound pressure. Virtually all existing microphone designs are intended to respond to sound pressure. The structures examined here consist of thin, micro-scale, cantilever beams. The viscous forces that drive the beams are proportional to the relative velocity between the beams and fluid medium. The beams' movement in response to sound is similar to that of the air in a plane acoustic wave. The thermal-mechanical noise of these beams is found to be a very weak function of their width and length; the size of the sensing structure does not appear to significantly affect the performance. This differs from the well-known importance of the size of a pressure-sensing microphone in determining the pressure-referred noise floor. Creating microphones that sense fluid motion rather than pressure could enable a significant reduction in the size of the sensing element. Calculated results are revealed to be in excellent agreement with the measured pressure-referred thermal noise.

3.
Anticancer Drugs ; 34(1): 144-154, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36539367

RESUMEN

Long noncoding RNA taurine-upregulated gene1 (TUG1) has been reported to be implicated in the chemo-resistance of bladder cancer. Hence, this study aimed to survey regulatory mechanism by which TUG1 regulates the chemo-resistance of bladder cancer cells to doxorubicin (DOX). Relative expression of TUG1, miR-582-5p, and karyopherin alpha 2 (KPNA2) was detected by qRT-PCR. The viability and proliferation of DOX-resistant bladder cancer cells were determined by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. Protein levels were measured by western blot analysis. The apoptosis, migration, and invasion of DOX-resistant bladder cancer cells were determined by flow cytometry or transwell assays. The relationship between TUG1 or KPNA2 and miR-582-5p was verified by dual-luciferase reporter assay. TUG1 and KPNA2 were upregulated while miR-582-5p was downregulated in resistant bladder cancer tissues and cells. TUG1 inhibition elevated cell chemo-sensitivity, facilitated cell apoptosis, and curbed proliferation, migration, invasion, and autophagy of DOX-resistant bladder cancer cells. Also, TUG1 acted as a sponge for miR-582-5p, and miR-582-5p inhibitor reversed TUG1 knockdown-mediated influence on DOX chemo-sensitivity and malignant behaviors in DOX-resistant bladder cancer cells. Furthermore, miR-582-5p targeted KPNA2, and KPNA2 overexpression counteracted the inhibitory impact of miR-582-5p mimic on DOX chemo-resistance and malignant behaviors in DOX-resistant bladder cancer cells. Additionally, TUG1 silencing inactivated the PI3K/AKT pathway through sponging miR-582-5p. TUG1 sponged miR-582-5p to increase KPNA2 expression and activated the KPNA2/PI3K/AKT pathway, thereby elevating DOX chemo-resistance and malignant behaviors in bladder cancer cells.


Asunto(s)
MicroARNs , ARN Largo no Codificante , Neoplasias de la Vejiga Urinaria , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Taurina , Proliferación Celular/genética , Doxorrubicina/farmacología , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/genética , Movimiento Celular/genética , alfa Carioferinas/genética
4.
Nanotechnology ; 34(40)2023 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-37462320

RESUMEN

The oxidation mechanism of atomically thin molybdenum disulfide (MoS2) plays a critical role in its nanoelectronics, optoelectronics, and catalytic applications, where devices often operate in an elevated thermal environment. In this study, we systematically investigate the oxidation of mono- and few-layer MoS2flakes in the air at temperatures ranging from 23 °C to 525 °C and relative humidities of 10%-60% by using atomic force microscopy (AFM), Raman spectroscopy and x-ray photoelectron spectroscopy. Our study reveals the formation of a uniform nanometer-thick physical adsorption layer on the surface of MoS2, which is attributed to the adsorption of ambient moisture. This physical adsorption layer acts as a thermal shield of the underlying MoS2lattice to enhance its thermal stability and can be effectively removed by an AFM tip scanning in contact mode or annealing at 400 °C. Our study shows that high-temperature thermal annealing and AFM tip-based cleaning result in chemical adsorption on sulfur vacancies in MoS2, leading to p-type doping. Our study highlights the importance of humidity control in ensuring reliable and optimal performance for MoS2-based electronic and electrochemical devices and provides crucial insights into the surface engineering of MoS2, which are relevant to the study of other two-dimensional transition metal dichalcogenide materials and their applications.

5.
Plant Dis ; 2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36782088

RESUMEN

Shatangju (Citrus reticulata Blanco cv. Shatangju) belongs to genus Citrus and was cultivated extensively in southern China. In April 2022, a leaf blight-like symptom (firstly brown spots appeared on infecting leaves, then these brown spots extended, finally the whole leaves displayed blight-like symptom) was observed on 5%~10% of Shatangju seedlings (around five hundreds in total) in an orchard located in Wuhan city, Hubei, China. Diseased leaves from three seedlings were collected and cut into pieces (0.2 to 0.5 cm). These pieces were surface-sterilized using 75% ethanol for 3 min, rinsed with sterile distilled water for several times, then placed on potato dextrose agar (PDA) and incubated at 26°C with 12-h light/dark cycle. Over 20 pieces plated, wherein 30% were identified as Colletotrichum fructicola, 60% as Neopestalotiopsis spp., and 10% developed saprophytes. C. fructicola was a known pathogen on citrus, thus Neopestalotiopsis spp. was further investigated. Eight single-conidium colonies of the Neopestalotiopsis spp. were obtained, wherein STJ-8 was chosen as a representative for further study. The average growth rate of STJ-8 was 15.1±0.5 mm/day (n=5). Fungal colonies produced white cottony mycelium with abundant black acervuli distributed in concentric rings 6-8 days after planting, which ranged from 342.3 to 710.5 µm in diameter (n=100). Conidia were fusoid, five cells, four septa with average dimensions of 25.36×5.47 µm (n=100). Basal and apical cells were hyaline, wherein three middle cells were brown with darker septa. The apical cell was cylindrical with two to three transparent accessory filaments (13.7 to 30.5 µm in length, n=80). Basal cell was conic with an appendage (4.1 to 8.8 µm in length, n=40). Partial sequences of internal transcribed spacer (ITS), translation elongation factor 1-alpha (TEF-1α), and ß-tubulin (TUB2) were amplified with reported primers (White et al. 1990; Lee et al. 2006; Maharachchikumbura et al. 2014), sequenced, and submitted to GenBank (accession nos. ITS: OP236541; TEF-1α: OP250124; TUB2:OP263094). BLASTn results showed 100% identity with the corresponding sequences of Neopestalotiopsis rosae. A multilocus phylogenetic analysis showed STJ-8 was closest to N. rosae. Thus, STJ-8 was identified as N. rosae. Pathogenicity tests were performed on one-year-old Shatangju seedlings and detached primary leaves by inoculating needle-wounded leaves with seven days old 5-mm mycelial plugs/acervuli (about 5000 spores) of STJ-8. Control seedlings/leaves were inoculated with 5-mm PDA plugs/sterile water drops. All inoculated detached leaves were cultured at same the place with STJ-8 cultured, while inoculated seedlings were put in a growth chamber at 26°C under a 16-h light/dark cycle (60% humidity). Symptoms developed on all inoculated leaves (except healthy control) 2 and 4 days post-inoculation by mycelial plugs and acervuli, respectively. N. rosae was re-isolated from the inoculated leaves, confirming Koch's postulates. N. rosae has been reported to cause diseases on various plants worldwide (Rebollar-Alviter et al. 2020; Xavier et al. 2021; Lawrence et al. 2022). In China, N. rosae has been reported to cause leaf spot/blight on pecan and strawberry (Wu et al. 2021; Gao et al. 2022), which caused great loss on these crops. To our knowledge, this is the first report of N. rosae causing leaf disease on citrus. Our study is important for developing control strategies against N. rosae in future.

6.
Arch Pharm (Weinheim) ; 356(3): e2200479, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36372519

RESUMEN

Cancer is one of the leading causes of death across the world, and the prevalence and mortality rates of cancer will continue to grow. Chemotherapeutics play a critical role in cancer therapy, but drug resistance and side effects are major hurdles to effective treatment, evoking an immediate need for the discovery of new anticancer agents. Triazines including 1,2,3-, 1,2,4-, and 1,3,5-triazine have occupied a propitious place in drug design and development due to their excellent pharmacological profiles. Mechanistically, triazine derivatives could interfere with various signaling pathways to induce cancer cell death. Hence, triazine derivatives possess potential in vitro and in vivo efficacy against diverse cancers. In particular, triazine hybrids are able to overcome drug resistance and reduce side effects. Moreover, several triazine hybrids such as brivanib (indole-containing pyrrolo[2,1-f][1,2,4]triazine), gedatolisib (1,3,5-triazine-urea hybrid), and enasidenib (1,3,5-triazine-pyridine hybrid) have already been available in the market. Accordingly, triazine hybrids are useful scaffolds for the discovery of novel anticancer chemotherapeutics. This review focuses on the anticancer activity of 1,2,3-, 1,2,4-, and 1,3,5-triazine hybrids, together with the structure-activity relationships and mechanisms of action developed from 2017 to the present. The enriched structure-activity relationships may be useful for further rational drug development of triazine hybrids as potential clinical candidates.


Asunto(s)
Antineoplásicos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Neoplasias , Humanos , Relación Estructura-Actividad , Antineoplásicos/farmacología , Neoplasias/tratamiento farmacológico , Diseño de Fármacos , Triazinas/farmacología , Estructura Molecular
7.
Sensors (Basel) ; 23(19)2023 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-37837152

RESUMEN

Plant factory is an important field of practice in smart agriculture which uses highly sophisticated equipment for precision regulation of the environment to ensure crop growth and development efficiently. Environmental factors, such as temperature and humidity, significantly impact crop production in a plant factory. Given the inherent complexities of dynamic models associated with plant factory environments, including strong coupling, strong nonlinearity and multi-disturbances, a nonlinear adaptive decoupling control approach utilizing a high-order neural network is proposed which consists of a linear decoupling controller, a nonlinear decoupling controller and a switching function. In this paper, the parameters of the controller depend on the generalized minimum variance control rate, and an adaptive algorithm is presented to deal with uncertainties in the system. In addition, a high-order neural network is utilized to estimate the unmolded nonlinear terms, consequently mitigating the impact of nonlinearity on the system. The simulation results show that the mean error and standard error of the traditional controller for temperature control are 0.3615 and 0.8425, respectively. In contrast, the proposed control strategy has made significant improvements in both indicators, with results of 0.1655 and 0.6665, respectively. For humidity control, the mean error and standard error of the traditional controller are 0.1475 and 0.441, respectively. In comparison, the proposed control strategy has greatly improved on both indicators, with results of 0.0221 and 0.1541, respectively. The above results indicate that even under complex conditions, the proposed control strategy is capable of enabling the system to quickly track set values and enhance control performance. Overall, precise temperature and humidity control in plant factories and smart agriculture can enhance production efficiency, product quality and resource utilization.

8.
Int J Mol Sci ; 24(21)2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37958939

RESUMEN

Cold is one of the major limiting factors for citrus production, particularly extreme cold waves. Therefore, it is of great importance to develop cold-tolerant varieties and clarify their cold tolerance mechanisms in citrus breeding. In this study, comparative transcriptomic and physiological analyses were performed to dissect the cold tolerance mechanism of Guijing2501 (GJ2501), a new satsuma mandarin (Citrus unshiu) variety with about 1 °C lower LT50 (the median lethal temperature) relative to Guijing (GJ). The physiological analysis results revealed that GJ2501 is more cold-tolerant with less photoinhibition, PSII photodamage, and MDA accumulation, but higher POD activity than GJ under cold stress. Comparative transcriptomic analysis identified 4200 DEGs between GJ and GJ2501, as well as 4884 and 5580 up-regulated DEGs, and 5288 and 5862 down-regulated DEGs in response to cold stress in GJ and GJ2501, respectively. "Photosynthesis, light harvesting" and "photosystem" were the specific and most significantly enriched GO terms in GJ2501 in response to cold stress. Two CuELIP1 genes (encoding early light-induced proteins) related to the elimination of PSII photodamage and photoinhibition were remarkably up-regulated (by about 1000-fold) by cold stress in GJ2501 as indicated by RT-qPCR verification. Overexpression of CuELIP1 from GJ2501 in transgenic Arabidopsis protected PSII against photoinhibition under cold stress. Taken together, the cold tolerance of GJ2501 may be ascribed to its higher photoprotective capacity under cold stress.


Asunto(s)
Citrus , Transcriptoma , Citrus/genética , Fitomejoramiento , Perfilación de la Expresión Génica , Respuesta al Choque por Frío/genética , Frío , Regulación de la Expresión Génica de las Plantas
9.
BMC Genomics ; 23(1): 185, 2022 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-35249536

RESUMEN

BACKGROUND: Citrus is one of the most important fresh fruit crops worldwide. Juice sac granulation is a physiological disorder, which leads to a reduction in soluble solid concentration, total sugar, and titratable acidity of citrus fruits. Pectin methylesterase (PME) catalyzes the de-methylesterification of homogalacturonans and plays crucial roles in cell wall modification during plant development and fruit ripening. Although PME family has been well investigated in various model plants, little is known regarding the evolutionary property and biological function of PME family genes in citrus. RESULTS: In this study, 53 non-redundant PME genes were identified from Citrus sinensis genome, and these PME genes were divided into four clades based on the phylogenetic relationship. Subsequently, bioinformatics analyses of gene structure, conserved domain, chromosome localization, gene duplication, and collinearity were performed on CsPME genes, providing important clues for further research on the functions of CsPME genes. The expression profiles of CsPME genes in response to juice sac granulation and low-temperature stress revealed that CsPME genes were involved in the low temperature-induced juice sac granulation in navel orange fruits. Subcellular localization analysis suggested that CsPME genes were localized on the apoplast, endoplasmic reticulum, plasma membrane, and vacuole membrane. Moreover, yeast one-hybrid screening and dual luciferase activity assay revealed that the transcription factor CsRVE1 directly bound to the promoter of CsPME3 and activated its activity. CONCLUSION: In summary, this study conducts a comprehensive analysis of the PME gene family in citrus, and provides a novel insight into the biological functions and regulation patterns of CsPME genes during juice sac granulation of citrus.


Asunto(s)
Citrus sinensis , Citrus , Hidrolasas de Éster Carboxílico/metabolismo , Citrus/genética , Citrus/metabolismo , Citrus sinensis/genética , Citrus sinensis/metabolismo , Frutas/genética , Frutas/metabolismo , Filogenia
10.
Plant Dis ; 2022 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-35876760

RESUMEN

Trifoliate orange (Poncirus trifoliata L) is a thorny tree of the Rue family, which is extensively used as citrus rootstock in China. In January 2021, several leaf yellowing, declining, and wilting citrus seedlings grafted on trifoliate orange rootstock with rotted main roots were observed in orchards located in Wuhan city, Hubei, China. In old orchards, the incidence of diseased roots was approximately 90%. Diseased roots from seven plants were collected and cut into small pieces (0.2 to 0.5 cm). These pieces were then surface-sterilized using 0.1% mercury bichloride for 3 min, 75% ethanol for 3 min, rinsed with sterile distilled water for several times, and then placed on potato dextrose agar (PDA) supplemented with 0.05% lactic acid (v/v), and incubated at at 25±2°C in dark. Fifty-threesingle-conidium isolates with morphological characteristics similar to Fusarium spp. were obtained (Leslie and Summerell 2006), which displayed two kinds of colony morphology. Thirty isolates showed white to orange-white abundant aerial mycelium in rings and acquired a yellow to orange pigmentation, tweenty-three isolates showed white to pink, fluffy aerial mycelium in rings and acquired an orange to red pigmentation. Isolate WG-1 and HrmY-9 from each group were used for future identification. The average colony growth rate of WG-1 and HrmY-9 on PDA was 0.95±0.06 and 0.69±0.11 mm/day, n=4, respectively. WG-1 produced numerous oval, unicellular microconidia without septa, 4.03-9.87×1.01-5.13 µm, n=80 and very few macroconidia with two to four septa, narrowed at both ends, 11.08-22.64×1.67-4.91 µm, n=30. HrmY-9 produced numerous curved macroconidia with three to four septa, 18.03-37.33×2.16-7.8 µm, n=80, microconidia were unicellular, oval, and 5.33-16.19×1.74-6.51 µm, n=50. Sequences of internal transcribed spacer (ITS), translation elongation factor 1-alpha (EF-1α), and DNA-directed RNA polymerase largest subunit (RPB1) genes were amplified with the primers ITS1/ITS4, EF1a-F/EF1a-R, and RPB1-F5/RPB1-R8, respectively (White et al. 1990, O'Donnell et al. 1998, O'Donnell et al. 2010), sequenced and deposited in GenBank. Sequences of isolate WG-1 (GenBank accession No. ON045437, ON063232 and ON089664) and HrmY-9 (GenBank accession No. ON045438, ON063233 and ON089665) were 100% identical with the corresponding sequences of Fusarium oxysporum (OM876904, JF430180, and MT568959) and F. solani (MT605584, MK617767, and MT305110), respectively. Based on above results, WG-1 and HrmY-9 was identified as F. oxysporum and F. solani, respectively. Pathogenicity test were performed on healthy one-year-old trifoliate orange seedlings by dipping their injured roots into conidial suspension (50 ml, 1×106 conidia/mL) for 1 h and the rest of conidial suspension was added to the pot after replanting to make sure the inoculum was in contact with the roots. Roots of control plants were inoculated with sterilized water. All experiments were repeated twice. All plants were cultured at 26°C under a 16-h light/dark cycle. Typical symptoms developed on most of inoculated seedlings two months post inoculation. No disease symptoms appeared on control plants. Same colonies were reisolated from the inoculated roots, confirming Koch's postulates. To our knowledge, this is the first report of F. oxysporum and F. solani causing root rot on trifoliate orange rootstock in China. The identification of F. oxysporum and F. solani as the causal agents of the observed root rot on trifoliate orange rootstock is critical to the prevention and control of this disease in the future.

11.
Anal Chem ; 92(7): 4721-4725, 2020 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-32151135

RESUMEN

Recently, small molecule photoacoustic sensors have emerged prominently in chem/biosensing owing to their excellent performance of high contrast, high resolution, and deep penetration depth. However, there has been little report on a photoacoustic sensor for Pd2+ detection so far. Herein, a ratiometric photoacoustic Pd2+ sensor, Cy-DPA, based on cyanine fluorophore has been developed. The absorbance peak of Cy-DPA shifts from 710 to 770 nm after the interaction with Pd2+, thus producing a strong PA signal output at 770 nm. As-prepared Cy-DPA could sensing palladium with high sensitivity (27 nM) and selectivity in a fast response (<30 s), which opened new avenue for Pd2+ real-time detection in vivo.


Asunto(s)
Carbocianinas/química , Colorantes Fluorescentes/química , Plomo/análisis , Iones/análisis , Estructura Molecular , Procesos Fotoquímicos , Teoría Cuántica
12.
J Gen Virol ; 98(3): 322-337, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27959772

RESUMEN

Histone deacetylase 6 (HDAC6) is a unique cytoplasmic deacetylase that regulates various important biological processes by preventing protein aggregation and deacetylating different non-histone substrates including tubulin, heat shock protein 90, cortactin, retinoic acid inducible gene I and ß-catenin. Growing evidence has indicated a dual role for HDAC6 in viral infection and pathogenesis: HDAC6 may represent a host defence mechanism against viral infection by modulating microtubule acetylation, triggering antiviral immune response and stimulating protective autophagy, or it may be hijacked by the virus to enhance proinflammatory response. In this review, we will highlight current data illustrating the complexity and importance of HDAC6 in viral pathogenesis. We will summarize the structure and functional specificity of HDAC6, and its deacetylase- and ubiquitin-dependent activity in key cellular events in response to virus infection. We will also discuss how HDAC6 exerts its direct or indirect histone modification ability in viral lytic-latency switch.


Asunto(s)
Histona Desacetilasas/fisiología , Virosis/enzimología , Virosis/virología , Fenómenos Fisiológicos de los Virus , Animales , Movimiento Celular , Núcleo Celular/virología , Histona Desacetilasa 6 , Histona Desacetilasas/química , Histonas/metabolismo , Humanos , Inmunidad Celular , Microtúbulos/metabolismo , Procesamiento Proteico-Postraduccional , Ubiquitina/metabolismo
13.
Molecules ; 21(8)2016 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-27455233

RESUMEN

Three new indole alkaloids, named naucleamide G (1), and nauclealomide B and C (5 and 6), were isolated from the n-BuOH-soluble fraction of an EtOH extract of the leaves of Nauclea officinalis, together with three known alkaloids, paratunamide C (2), paratunamide D (3) and paratunamide A (4). The structures with absolute configurations of the new compounds were identified on the basis of 1D and 2D NMR, HRESIMS, acid hydrolysis and quantum chemical circular dichroism (CD) calculation. According to the structures of isolated indole alkaloids, their plausible biosynthetic pathway was deduced.


Asunto(s)
Alcaloides/química , Hojas de la Planta/química , Rubiaceae/química , Alcaloides/aislamiento & purificación , Carbolinas/química , Carbolinas/aislamiento & purificación , Dicroismo Circular , Glucósidos/química , Glucósidos/aislamiento & purificación , Glicósidos/química , Glicósidos/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Estructura Molecular , Extractos Vegetales/química
14.
Pharm Dev Technol ; 20(7): 812-819, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24909735

RESUMEN

Topotecan hydrochloride (TPT) has potential for the treatment of ovarian cancer, but the activity of TPT tends to decrease due to the ring-opening at physiological pH. In this study, we proposed to incorporate TPT liposomes into injectable thermosensitive in situ hydrogel, consisting of chitosan (CS) and ß-glycerophosphate (ß-GP), for sustained release and preservation of active lactone form of TPT. The rheology studies were carried out to investigate the sol-gel temperature, flow behavior and viscosity of these CS/ß-GP systems. The optimized formulation exhibited sol-gel transition at 40.2 ± 0.4 °C, with pseudoplastic flow behavior. The drug release rate of TPT liposomes loaded CS/ß-GP hydrogel in phosphate buffer saline (pH = 7.4) was found to be slowed down, and the lactone fraction of TPT in the hydrogel matrix was maintaining 40% after 50 h. In addition, the antitumor efficacy in Kunming mice bearing Hepatoma-22 tumor, after intratumoral injection of TPT liposomes loaded CS/ß-GP hydrogel, was higher than that of TPT in saline and TPT in CS/ß-GP hydrogel. Those results demonstrated that TPT liposomes loaded CS/ß-GP hydrogel could become a potential formulation for improving the antitumor efficacy of TPT and suggested an important technology platform for intratumoral administration of derivative of camptothecin-family drugs.

15.
J Med Imaging (Bellingham) ; 11(3): 034504, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38827779

RESUMEN

Purpose: Accurate segmentation of the endometrium in ultrasound images is essential for gynecological diagnostics and treatment planning. Manual segmentation methods are time-consuming and subjective, prompting the exploration of automated solutions. We introduce "segment anything with inception module" (SAIM), a specialized adaptation of the segment anything model, tailored specifically for the segmentation of endometrium structures in ultrasound images. Approach: SAIM incorporates enhancements to the image encoder structure and integrates point prompts to guide the segmentation process. We utilized ultrasound images from patients undergoing hysteroscopic surgery in the gynecological department to train and evaluate the model. Results: Our study demonstrates SAIM's superior segmentation performance through quantitative and qualitative evaluations, surpassing existing automated methods. SAIM achieves a dice similarity coefficient of 76.31% and an intersection over union score of 63.71%, outperforming traditional task-specific deep learning models and other SAM-based foundation models. Conclusions: The proposed SAIM achieves high segmentation accuracy, providing high diagnostic precision and efficiency. Furthermore, it is potentially an efficient tool for junior medical professionals in education and diagnosis.

16.
Curr Med Chem ; 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39192650

RESUMEN

AIM: This study explored the role of the Hedgehog pathway in epithelial cells during cervical cancer [CC] progression, providing new insights for improving current CC treatment. BACKGROUND: Abnormal activation of the Hedgehog signaling pathway is associated with the malignant transformation of CC epithelial cells. Single-cell atlas of CC and the role of Hedgehog pathway in epithelial cells during CC progression remain to be explored. OBJECTIVE: To comprehensively analyze the mechanism of Hedgehog pathway activation in CC epithelial cells and its impact on tumor progression by applying single-cell RNA sequencing [scRNA-seq] analysis. METHODS: The scRNA-seq data were acquired from the Gene Expression Omnibus [GEO] database and then processed with the Seurat package. FindNeighbors and Find- Clusters functions were applied to cluster the cells. The CellMarker database was used for subgroup annotation. Differentially expressed genes [DEGs] in each cell subgroup were filtered by FindAllMarkers function. Biological function analysis for the gene set of interest was performed using Clusterprofiler package. AUCell function was employed to calculate the score of the Hedgehog pathway. The differentiation trajectory in epithelial cell subtypes was generated by performing Pseudotime analysis. Finally, protein-protein network [PPI] was used to investigate the interactions between the Hedgehog pathway and other pathways enriched in the gene set of interest. RESULTS: A total of 9 major cell subpopulations were classified and the proportion of epithelial cells was the highest in CC samples. Further analysis revealed that the Hedgehog pathway was abnormally activated in STYK1+ and TP73+ epithelial cell subtypes. Pseudo-time trajectory analysis showed that the differentiation trajectory of STYK1+ epithelial cells gradually transformed into defense-to-virus cells or into proliferation cells, while TP73+ epithelial cells eventually differentiated into two branches of response to estrogen and virus-induced proliferation. PPI analysis showed that the Hedgehog pathway was involved in the proliferation and viral process of epithelial cells in CC. CONCLUSION: The current study comprehensively analyzed the features of CC samples and differentiation trajectories of epithelial cell subtypes, as well as the role of the Hedgehog pathway in epithelial cells during CC progression. More importantly, effective target genes were discovered for the molecular diagnosis and precise treatment of CC.

17.
Front Plant Sci ; 14: 1223820, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37457356

RESUMEN

'Lane Late', a late-maturing navel orange cultivar, is mainly distributed in the Three Gorges Reservoir area, which matures in the late March of the next year and needs overwintering cultivation. Citrus fruit granulation is a physiological disorder, which is characterized by lignification and dehydration of juice sac cells, seriously affecting the commercial value of citrus fruits. The pre-harvest granulation of late-maturing navel orange is main caused by low temperature in the winter, but its mechanism and regulation pattern remain unclear. In this study, a SG2-type R2R3-MYB transcription factor, CsMYB15, was identified from Citrus sinensis, which was significantly induced by both juice sac granulation and low temperature treatment. Subcellular localization analysis and transcriptional activation assay revealed that CsMYB15 protein was localized to the nucleus, and it exhibited transcriptional activation activity in yeast. Over-expression of CsMYB15 by stable transformation in navel orange calli and transient transformation in kumquat fruits and navel orange juice sacs significantly increased lignin content in the transgenic lines. Further, Yeast one hybrid, EMSA, and LUC assays demonstrated that CsMYB15 directly bound to the Cs4CL2 promoter and activated its expression, thereby causing a high accumulation of lignin in citrus. Taken together, these results elucidated the biological function of CsMYB15 in regulating Cs4CL2-mediated lignin biosynthesis, and provided novel insight into the transcriptional regulation mechanism underlying the juice sac granulation of late-maturing navel orange.

18.
Amino Acids ; 43(3): 1147-56, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22134582

RESUMEN

Sauvagine is a potent and broad-spectrum biologically active peptide of 40 amino acid residues originally isolated from the skin of the South American frog, Phyllomedusa sauvagei. Since its discovery, no additional sauvagine structures have been reported. Following the discovery of sauvagine, peptides with similar primary structures/activities were identified in mammalian brain [corticotropin-releasing factor (CRF) and urocortin]. Here, we report the identification of a second sauvagine from the Mexican giant leaf frog, Pachymedusa dacnicolor, which displays primary structural features of both sauvagine and CRF. A cDNA encoding the peptide precursor was "shotgun" cloned from a cDNA library constructed from lyophilised skin secretion by 3'- and 5'-RACE reactions. From this, the primary structure of a 38-mer peptide was deduced and this was located in reverse phase HPLC fractions of skin secretion and both its mass and structure were confirmed by mass spectrometry. The biological activities of synthetic replicates of PD-sauvagine and sauvagine were compared using two different mammalian smooth muscle preparations and the novel peptide was found to be more potent in both. Bioinformatic analyses of PD-sauvagine revealed that it shared different regional sequence identities with both sauvagine and CRF.


Asunto(s)
Proteínas Anfibias/metabolismo , Anuros/metabolismo , Colon/efectos de los fármacos , Precursores de Proteínas/metabolismo , Piel/metabolismo , Vejiga Urinaria/efectos de los fármacos , Secuencia de Aminoácidos , Proteínas Anfibias/genética , Proteínas Anfibias/farmacología , Animales , Secuencia de Bases , Cromatografía Líquida de Alta Presión , Clonación Molecular , Relación Dosis-Respuesta a Droga , Cobayas , Técnicas In Vitro , Masculino , Datos de Secuencia Molecular , Contracción Muscular/efectos de los fármacos , Precursores de Proteínas/genética , Precursores de Proteínas/farmacología , Señales de Clasificación de Proteína , Estructura Secundaria de Proteína , Ratas , Ratas Wistar , Análisis de Secuencia de ADN , Análisis de Secuencia de Proteína , Homología de Secuencia de Aminoácido
19.
Investig Clin Urol ; 63(5): 577-588, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36068004

RESUMEN

PURPOSE: This research concentrated on the biological effects and special mechanism of circ_0003221 in bladder cancer (BLCA). MATERIALS AND METHODS: The level quantification by reverse transcription-quantitative polymerase chain reaction was administrated for circ_0003221, microRNA-892b (miR-892b) and 24-dehydrocholesterol reductase (DHCR24). The biological behaviors were assessed by EDU assay and colony formation assay for proliferation, and transwell assay for cell motility. Glycolytic metabolism was tested using the commercial kits. DHCR24 protein level and cell markers were measured through western blot. The analysis of interaction potential was conducted via dual-luciferase reporter assay and pull-down assay. Circ_0003221 was implemented via tumor xenograft assay in vivo. RESULTS: Abnormal circ_0003221 upregulation was affirmed in BLCA. BLCA cell proliferation, motility and glycolysis were impeded after circ_0003221 level was knocked down. MiR-892b was identified as a target for circ_0003221. Reduction of miR-892b relieved si-circ_0003221-induced anti-tumor response in BLCA cells. In addition, miR-892b targeted DHCR24 and circ_0003221/miR-892b could regulate the level of DHCR24. The effects of si-circ_0003221 were also counteracted by DHCR24 overexpression. CONCLUSIONS: The current evidence elucidated circ_0003221 targeted miR-892b to elevate the DHCR24 level, thus accelerating cell development and glycolytic metabolism of BLCA cells.


Asunto(s)
MicroARNs , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH , Neoplasias de la Vejiga Urinaria , Apoptosis , Movimiento Celular/genética , Regulación Neoplásica de la Expresión Génica , Humanos , MicroARNs/genética , Proteínas del Tejido Nervioso/metabolismo , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/genética , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/metabolismo , ARN Circular/genética , Regulación hacia Arriba , Neoplasias de la Vejiga Urinaria/genética
20.
Sci Rep ; 12(1): 5200, 2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35338250

RESUMEN

In recent years, whole steel frame steel greenhouses have become increasingly prevalent. With the characteristics of large flexibility and small mass, whole steel frame steel greenhouses are sensitive to wind loads. However, studies on the safety of whole steel frame steel greenhouses under wind loads are still limited. In this study, a 10 m span whole steel frame solar greenhouse was taken as the research objective. Taking the Davenport spectrum as the target spectrum, the time history of the wind speed was simulated by the harmonic superposition method. The finite element model of the greenhouse structure was established using ANSYS software. The simulated wind pressure was applied on the greenhouse structure for dynamic response analysis. The dynamic response results were compared with the static analysis results under average wind load. The results showed that the greenhouse structure mainly bears bending stress under wind load. The bending stress, axial stress and displacement of the greenhouse skeleton under average wind loads are lower than those under instantaneous wind loads. It is necessary to consider the dynamic characteristics of wind loads in the design of solar greenhouses. A wind-induced vibration coefficient is obtained, which can be used to convert the dynamic load into the equivalent static load and improve its design efficiency.

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