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1.
Eur J Clin Microbiol Infect Dis ; 43(5): 905-914, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38472518

RESUMO

BACKGROUND: The existing literature lacks studies examining the epidemiological link between scrub typhus and deep vein thrombosis (DVT) or pulmonary embolism (PE), and the long-term outcomes. The objective of this study is to explore the potential association between scrub typhus and the subsequent risk of venous thromboembolism, and long-term mortality. METHOD: This nationwide cohort study identified 10,121 patients who were newly diagnosed with scrub typhus. Patients with a prior DVT or PE diagnosis before the scrub typhus infection were excluded. A comparison cohort of 101,210 patients was established from the general population using a propensity score matching technique. The cumulative survival HRs for the two cohorts were calculated by the Cox proportional hazards model. RESULT: After adjusting for sex, age, and comorbidities, the scrub typhus group had an adjusted HR (95% CI) of 1.02 (0.80-1.30) for DVT, 1.11 (0.63-1.93) for PE, and 1.16 (1.08-1.25) for mortality compared to the control group. The post hoc subgroup analysis revealed that individuals younger than 55 years with a prior scrub typhus infection had a significantly higher risk of DVT (HR: 1.59; 95% CI: 1.12-2.25) and long-term mortality (HR: 1.75; 95% CI, 1.54-1.99). CONCLUSION: The scrub typhus patients showed a 16% higher risk of long-term mortality. For those in scrub typhus cohort below 55 years of age, the risk of developing DVT was 1.59 times higher, and the risk of mortality was 1.75 times higher. Age acted as an effect modifier influencing the relationship between scrub typhus and risk of new-onset DVT and death.


Assuntos
Tifo por Ácaros , Tromboembolia Venosa , Humanos , Tifo por Ácaros/complicações , Tifo por Ácaros/epidemiologia , Tifo por Ácaros/mortalidade , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Adulto , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/mortalidade , Tromboembolia Venosa/etiologia , Fatores de Risco , Estudos de Coortes , Modelos de Riscos Proporcionais , Idoso de 80 Anos ou mais , Embolia Pulmonar/mortalidade , Embolia Pulmonar/epidemiologia , Embolia Pulmonar/etiologia , Adulto Jovem
2.
Fam Pract ; 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37756627

RESUMO

BACKGROUND: Proton pump inhibitors (PPIs) and histamine-2 receptor (H2) antagonists change the gastric pH and reduce the intestinal absorption of nonheme iron. Case reports and case-control studies have demonstrated that absorption of iron is affected by gastric acidity, but the clinical importance of these drug-drug interactions has remained uncertain. OBJECTIVES: The present case-control study employed 2 million longitudinal claims in 2011-2018 in the Taiwan National Health Insurance Research Database to investigate the impact of PPIs/H2 antagonists on the occurrence of iron-deficiency anaemia (IDA). METHODS: The present study retrospectively compared exposure to PPIs/H2 antagonists for 1 year among 5,326 cases with IDA and 21,304 matched controls. The postdiagnosis prescribing pattern was also calculated to understand current practice. RESULTS: Long-term (≥2 month) use of PPIs/H2 antagonists resulted in a higher risk of developing IDA than noncontinuous use/nonuse of those drugs (adjusted odds ratio [aOR] = 2.36, 95% confidence interval [CI] = 1.94-2.86, P < 0.001). There were significant changes in the postdiagnosis prescribing patterns of PPIs/H2 antagonists. The risk of developing IDA remained significant in the female subgroup (aOR = 2.16, 95% CI = 1.73-2.70, P < 0.001) and was even more prominent in those aged ≥ 50 years (aOR = 2.68, 95% CI = 1.94-3.70, P < 0.05). CONCLUSIONS: This study found that long-term use of PPIs/H2 antagonists increased the risk of developing IDA, and there was strong evidence of prescription pattern adjustments postdiagnosis. Physicians and pharmacists should be aware of this risk when patients are expected to take or have been taking PPIs/H2 antagonists for the long term.


Proton pump inhibitors (PPIs) and histamine-2 receptor (H2) antagonists, 2 kinds of gastric suppressants commonly used for gastroesophageal reflux disease, decrease iron absorption in the gut and thus increase the risk of developing iron-deficiency anaemia (IDA). We constructed a retrospective matched case-control study within the Taiwan National Health Insurance Research Database. The longer period of PPIs/H2 antagonists used, the higher risk of IDA was, with the highest risk in female elderly groups (adjusted odds ratio = 2.68 in females aged ≥ 50). PPI users had a higher risk than H2 antagonist users during the 1-year follow-up. The prescription patterns postdiagnosis of IDA witnessed considerable drops for both groups, with less than a 10th of original users remaining the usages (1.72% and 9.85% taking PPIs and H2 antagonists within 90 days after receiving a diagnosis, respectively). Physicians and pharmacists should be aware of the risk of developing IDA in patients currently undergoing or expected to take long-term gastric acid suppressants.

3.
Int J Biometeorol ; 67(7): 1251-1261, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37256387

RESUMO

This study investigated the applicability of expanded metal meshes (EMMs) in horizontal shading devices. We performed simulations and experiments with EMMs with different opening ratios and directions. We established various experimental and control groups to measure air temperature, surface temperature, and black globe temperature. After the comparison of simulation and experimental data, we used Grasshopper to simulate long-term climate situations. The research results can serve as reference for users in Tainan and provide customized suggestions. The findings can serve as a paradigm for parametric design to analyze EMMs. In design projects involving outdoor horizontal shading devices, these results can be used in the design phase for evaluation. Full-day measurements revealed that EMMs with small openings exhibited favorable shading effects. In the Tainan area, we suggest using north-facing EMMs; in our simulations result, 70% of sunshine did not pass through the mesh in a day. For shading equipment in the morning, west-facing EMMs should be used because they blocked 50-90% of sunshine. For recreational areas in the afternoon and evening, east-facing EMMs can block 50-90% of sunshine after noon. In Taiwan, south-facing EMMs are not advised because their shading performance is suboptimal in the morning and afternoon.


Assuntos
Clima , Temperatura , Taiwan
4.
Biochem Biophys Res Commun ; 636(Pt 1): 84-88, 2022 12 25.
Artigo em Inglês | MEDLINE | ID: mdl-36332486

RESUMO

Pregnenolone (P5) is a steroid that functions in the brain and in zebrafish embryogenesis. It is synthesized from cholesterol via the enzymatic activity of P450scc, encoded by CYP11A1. P5 exerts its function by activating CLIP1, which in turn promotes microtubule assembly necessary for many biological processes including embryogenesis. To examine the functional relatedness of CYP11A1 and CLIP1, we ablated the embryonic expression of both genes in zebrafish, i.e. cyp11a1 and clip1a. Two cyp11a1 knockout fish lines were generated. Both homozygous cyp11a1 knockout lines appeared normal. But the development of fish embryos was delayed and embryonic cell migration was reduced when cyp11a1 function was depleted of by morpholinos. This discrepancy in phenotypes by two different gene depletion methods was also observed for clip1a. While clip1a morphants are defective in embryogenesis, clip1a knockout fish appeared normal. The phenotypes depend on the methods that create gene depletion. While knockout fish lines do not have expected phenotypic defects, clip1a and cyp11a1 morpholinos both reduce embryonic cell migration. We have evaluated the usefulness of both methods of gene ablation, and conclude that CYP11A1 and CLIP1 function in the same pathway to promote embryogenesis.


Assuntos
Enzima de Clivagem da Cadeia Lateral do Colesterol , Peixe-Zebra , Animais , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Pregnenolona/metabolismo , Morfolinos/metabolismo , Desenvolvimento Embrionário/genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
5.
Int J Neuropsychopharmacol ; 25(4): 319-327, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-34958668

RESUMO

BACKGROUND: The reuniens (Re) and rhomboid (Rh) nuclei (ReRh) of the midline thalamus interconnect the hippocampus and the medial prefrontal cortex. The hippocampus and medial prefrontal cortex are both involved in the acquisition of trace fear conditioning, in which a conditioned stimulus (tone) and an aversive unconditioned stimulus (footshock) are paired but separated in time with a trace interval. Earlier, we demonstrated that ReRh inactivation during trace conditioning impaired the acquisition of cued fear. In contrast, ReRh inactivation during both conditioning and test resulted in heightened fear to tones during retrieval. Because there was a generalized contextual fear on top of heightened fear to tones in the latter experiment, here we aimed to examine the specific importance of the functional ReRh in cued fear and contextual fear through introducing prolonged contextual exposure. METHODS: The ReRh were pharmacologically inactivated with muscimol (or saline as controls) before each experimental session. RESULTS: We showed that although ReRh inactivation before trace fear conditioning impaired the acquisition of cued fear, the animals still acquired a certain level of fear to the tones. However, without the functional ReRh throughout the entire behavioral sessions, these animals showed heightened contextual fear that did not decline much with the passage of time, which generalized to the other context, and fear to tones reoccurred when the tones were presented. CONCLUSIONS: Our results suggested that functional ReRh are important for proper acquisition and expression of fear to context and tones acquired under trace procedure.


Assuntos
Medo , Núcleos da Linha Média do Tálamo , Animais , Condicionamento Clássico , Sinais (Psicologia) , Medo/fisiologia , Hipocampo/metabolismo , Núcleos da Linha Média do Tálamo/fisiologia , Ratos , Ratos Long-Evans
6.
Sensors (Basel) ; 22(5)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35271038

RESUMO

Almond is an extendible open-source virtual assistant designed to help people access Internet services and IoT (Internet of Things) devices. Both are referred to as skills here. Service providers can easily enable their devices for Almond by defining proper APIs (Application Programming Interfaces) for ThingTalk in Thingpedia. ThingTalk is a virtual assistant programming language, and Thingpedia is an application encyclopedia. Almond uses a large neural network to translate user commands in natural language into ThingTalk programs. To obtain enough data for the training of the neural network, Genie was developed to synthesize pairs of user commands and corresponding ThingTalk programs based on a natural language template approach. In this work, we extended Genie to support Chinese. For 107 devices and 261 functions registered in Thingpedia, 649 Chinese primitive templates and 292 Chinese construct templates were analyzed and developed. Two models, seq2seq (sequence-to-sequence) and MQAN (multiple question answer network), were trained to translate user commands in Chinese into ThingTalk programs. Both models were evaluated, and the experiment results showed that MQAN outperformed seq2seq. The exact match, BLEU, and F1 token accuracy of MQAN were 0.7, 0.82, and 0.88, respectively. As a result, users could use Chinese in Almond to access Internet services and IoT devices registered in Thingpedia.


Assuntos
Aprendizado Profundo , Prunus dulcis , China , Humanos , Semântica , Software
7.
Sensors (Basel) ; 22(10)2022 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-35632335

RESUMO

Automated inspection has proven to be the most effective approach to maintaining quality in industrial-scale manufacturing. This study employed the eye-in-hand architecture in conjunction with deep learning and convolutional neural networks to automate the detection of defects in forged aluminum rims for electric vehicles. RobotStudio software was used to simulate the environment and path trajectory for a camera installed on an ABB robot arm to capture 3D images of the rims. Four types of surface defects were examined: (1) dirt spots, (2) paint stains, (3) scratches, and (4) dents. Generative adversarial network (GAN) and deep convolutional generative adversarial networks (DCGAN) were used to generate additional images to expand the depth of the training dataset. We also developed a graphical user interface and software system to mark patterns associated with defects in the images. The defect detection algorithm based on YOLO algorithms made it possible to obtain results more quickly and with higher mean average precision (mAP) than that of existing methods. Experiment results demonstrated the accuracy and efficiency of the proposed system. Our developed system has been shown to be a helpful rim defective detection system for industrial applications.


Assuntos
Aprendizado Profundo , Robótica , Algoritmos , Redes Neurais de Computação
8.
Int J Mol Sci ; 23(10)2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35628344

RESUMO

Hypertension is associated with blood-brain barrier alteration and brain function decline. Previously, we established the 2-kidney,1-clip (2K1C) hypertensive mice model by renin-angiotensin system (RAS) stimulating. We found that 2K1C-induced hypertension would impair hippocampus-related memory function and decrease adult hippocampal neurogenesis. Even though large studies have investigated the mechanism of hypertension affecting brain function, there remains a lack of efficient ways to halt this vicious effect. The previous study indicated that running exercise ameliorates neurogenesis and spatial memory function in aging mice. Moreover, studies showed that exercise could normalize RAS activity, which might be associated with neurogenesis impairment. Thus, we hypothesize that running exercise could ameliorate neurogenesis and spatial memory function impairment in the 2K1C-hypertension mice. In this study, we performed 2K1C surgery on eight-weeks-old C57BL/6 mice and put them on treadmill exercise one month after the surgery. The results indicate that running exercise improves the spatial memory and neurogenesis impairment of the 2K1C-mice. Moreover, running exercise normalized the activated RAS and blood-brain barrier leakage of the hippocampus, although the blood pressure was not decreased. In conclusion, running exercise could halt hypertension-induced brain impairment through RAS normalization.


Assuntos
Hipertensão , Condicionamento Físico Animal , Animais , Barreira Hematoencefálica , Hipocampo , Camundongos , Camundongos Endogâmicos C57BL , Neurogênese , Permeabilidade , Condicionamento Físico Animal/métodos , Sistema Renina-Angiotensina , Memória Espacial
9.
Bioorg Med Chem Lett ; 28(14): 2493-2497, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29871848

RESUMO

Histone deacetylases (HDACs) decrease the acetylation level of histones and other non-histone proteins. Over expression of HDACs have been observed in cancers and other diseases. Targeted protein degradation by "hijacking" the natural ubiquitin-proteasome-system (UPS) recently emerged as a novel technology to "knock-out" endogenous disease-causing proteins. We applied this strategy to the development of the first small molecule degraders for zinc-dependent HDACs by conjugating non-selective HDAC inhibitors with E3 ubiquitin ligase ligands. Through cell-based assays, we discovered novel bifunctional molecules (dHDAC6) that could selectively degrade HDAC6. Further mechanistic studies indicated that HDAC6 was selectively removed by the UPS.


Assuntos
Desacetilase 6 de Histona/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Talidomida/análogos & derivados , Relação Dose-Resposta a Droga , Desacetilase 6 de Histona/metabolismo , Humanos , Estrutura Molecular , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/química , Relação Estrutura-Atividade , Talidomida/síntese química , Talidomida/química , Talidomida/farmacologia
10.
Nat Prod Res ; : 1-7, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38534130

RESUMO

Five trichothecenes including a new one, together with two previously undescribed benzene derivatives were isolated from the solid culture of Trichothecium sp. Their structures were established by 1D and 2D NMR data in conjunction with HR-ESI-MS analysis. Compounds 1-5 exhibited cytotoxicity against MCF-7 cell lines at various levels ranging from IC50 of 7.23 to 16.95 µM. Compound 6 decreased the concentration of blood lipids in zebra fish at the concentration of 20 µM.

11.
Taiwan J Obstet Gynecol ; 63(3): 409-413, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38802209

RESUMO

OBJECTIVE: Monochorionic-triamniotic (MCTA) triplet pregnancies following artificial reproductive technologies are uncommon. We report a case in which one of two transferred embryos differentiated into an MCTA triplet. This study aimed to investigate the potential factors contributing to MCTA triplet pregnancy. CASE REPORT: A 39-year-old woman underwent her second frozen embryo transfer with hatching blastocysts, which resulted in the detection of an MCTA triplet on ultrasonography. She delivered by cesarean section at 32 weeks of gestation, resulting in the birth of three live male infants. Her medical history and in vitro fertilization treatment were reviewed to identify potential causes. CONCLUSION: The etiology of MCTA triplet pregnancy remains multifactorial. In the presented case, prolonged in vitro culture to the blastocyst stage and inner cell mass splitting were potential contributing factors. Further research is needed to fully understand the complexity of MCTA triplet pregnancy.


Assuntos
Transferência Embrionária , Gravidez de Trigêmeos , Humanos , Feminino , Gravidez , Adulto , Transferência Embrionária/métodos , Taiwan , Fertilização in vitro/métodos , Masculino , Cesárea , Recém-Nascido , Âmnio , Ultrassonografia Pré-Natal
12.
Int J Biol Macromol ; : 133402, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38925177

RESUMO

Cuticle proteins, in conjunction with chitin, compose the insect exoskeleton, and play a key role in the growth, development, and molting of insects. However, the specific functions of most cuticular protein genes in the growth, development, and reproductive processes of the pea aphid (Acyrthosiphon pisum) remain unclear. In this study, we have identified six cuticle protein genes in the pea aphid, namely ApCP7, ApCP10, ApCP19, ApCP19.8-like, ApCP35 and ApCP62. We found that the expression levels of six genes were highly expressed during the adult stage, and except for ApCP10, which is highly expressed in the pea aphid cuticle, other genes were highly expressed in the ovaries. Subsequently, we observed that the survival rate and fecundity of pea aphid were significantly lower than those of the control group after silencing ApCP7 and ApCP62 through RNA interference. Furthermore, when ApCP7 transcript levels were reduced, aphid encountered difficulties in molting, were smaller in body sizes, and exhibited a darker body color. These results indicate that ApCP7 and ApCP62 are involved in the development and reproduction of pea aphid, and could be used as RNAi targets for controlling pea aphid.

13.
Int J Biol Macromol ; 266(Pt 2): 131359, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38580018

RESUMO

The combination of photothermal therapy (PTT) and photodynamic therapy (PDT) has emerged as a promising strategy for cancer treatment. However, the poor photostability and photothermal conversion efficiency (PCE) of organic small-molecule photosensitizers, and the intracellular glutathione (GSH)-mediated singlet oxygen scavenging largely decline the antitumor efficacy of PTT and PDT. Herein, a versatile nanophotosensitizer (NPS) system is developed by ingenious incorporation of indocyanine green (ICG) into the PEGylated chitosan (PEG-CS)-coated polydopamine (PDA) nanoparticles via multiple π-π stacking, hydrophobic and electrostatic interactions. The PEG-CS-covered NPS showed prominent colloidal and photothermal stability as well as high PCE (ca 62.8 %). Meanwhile, the Michael addition between NPS and GSH can consume GSH, thus reducing the GSH-induced singlet oxygen scavenging. After being internalized by CT26 cells, the NPS under near-infrared laser irradiation produced massive singlet oxygen with the aid of thermo-enhanced intracellular GSH depletion to elicit mitochondrial damage and lipid peroxide formation, thus leading to ferroptosis and apoptosis. Importantly, the combined PTT and PDT delivered by NPS effectively inhibited CT26 tumor growth in vivo by light-activated intense hyperthermia and redox homeostasis disturbance. Overall, this work presents a new tactic of boosting antitumor potency of ICG-mediated phototherapy by PEG-CS-covered NPS.


Assuntos
Quitosana , Glutationa , Nanopartículas , Fotoquimioterapia , Fármacos Fotossensibilizantes , Terapia Fototérmica , Polietilenoglicóis , Quitosana/química , Fotoquimioterapia/métodos , Animais , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Glutationa/metabolismo , Polietilenoglicóis/química , Camundongos , Nanopartículas/química , Terapia Fototérmica/métodos , Linhagem Celular Tumoral , Verde de Indocianina/química , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Oxigênio Singlete/metabolismo , Humanos , Apoptose/efeitos dos fármacos , Indóis/química , Indóis/farmacologia , Polímeros/química
14.
Talanta ; 254: 124193, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36549135

RESUMO

Foodborne diseases caused by pathogens may threaten public health and the social economy. We demonstrated a method for identifying pathogenic Listeria monocytogenes using DNA logic operations. To achieve accurate species distinguishing, three specific sequences of Listeria monocytogenes genomic DNA were screened out and used as the feature sequences. Three complementary probes with tag modification were designed as sensing elements and exert affinity for magnetic beads, glucose oxidase (GOx), and horseradish peroxidase (HRP). To obtain a digital output (YES/NO answer) for rapid determination, a Boolean logic function was employed. Three sensing probes enabled the recognition of the target sequence (input) and the formation of a target DNA/probe hybrid. Through magnetic separation and affinity binding events, the target DNA/probes hybrid led to the construction of GOx/HRP enzyme cascade, which produced a visualized color signal (output) in the presence of substrates, glucose, and 3, 3', 5, 5'-tetramethylbenzidine (TMB). A hybridization chain reaction (HCR) was coupled with this sensing scaffold to increase the binding of the enzyme cascade and amplify the output signal. The logical functional biosensor showed high selectivity of Listeria monocytogenes over other Listeria species. This sensing platform provides a simple, sensitive, and highly specific method for detecting Listeria monocytogenes.


Assuntos
Técnicas Biossensoriais , Listeria monocytogenes , Listeria monocytogenes/genética , Hibridização de Ácido Nucleico , DNA , Sondas de DNA/genética , Glucose Oxidase
15.
J Dent Sci ; 18(1): 414-419, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36643230

RESUMO

Background/purpose: In the warm gutta-percha technique, soft-type and regular-type gutta-percha are using for backfilling thermoplasticized injection system. However, there are limited reports about the properties of these backfilling gutta-percha. This study aimed to analyze and compare the composition, thermal behavior and compact force of two types of backfilling gutta-percha. Materials and methods: Soft-type and regular-type backfilling gutta-percha (B&L BioTech, Fairfax, VA, USA) were investigated. The inorganic and organic fractions of these gutta-perchas were separated by quantitative chemical analysis (n = 6). Their composition was analyzed using energy dispersive spectroscopy. Thermal behavior in response to temperature variations was analyzed using differential scanning calorimetry. Additionally, a compaction model was used to investigate the relation between compaction force and temperature (n = 10). Results: The soft-type contained more gutta-percha (3.69-5.85%), carbon ratio (38.96-48.52%) and less inorganic substance (86.51-90.45%), zinc ratio (29.36-35.67%). The composition ratio of two types gutta-percha were statistically significant different (P < 0.05). There were three phase transitions of the soft-type gutta-percha which started at 39.84 °C, 49.32 °C and 54.15 °C while the two phase transitions of the regular-type gutta-percha started at 40.48 °C and 53.45 °C. The glass transition temperature of the regular-type gutta-percha (44.24 °C) was higher than that of the soft-type gutta-percha (40.66 °C). Under various setting temperature, the higher compaction force in the regular-type gutta-percha was required (P < 0.05). Conclusion: The different components in gutta-percha contribute to its differences in thermal behavior. The soft-type had a higher proportion of gutta-percha and lower ZnO which makes the fluidity better than the regular-type.

16.
Pharmaceutics ; 15(1)2023 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-36678844

RESUMO

The blocking of programmed death-ligand 1 (PD-L1) in tumor cells represents a powerful strategy in cancer immunotherapy. Using viral vectors to deliver the cargo for inactivating the PD-L1 gene could be associated with host cell genotoxicity and concomitant immune attack. To develop an alternative safe gene delivery method, we designed a unique combination for miRNA34a delivery using a transgene carrier in the form of iron oxide magnetic nanoparticles (IONPs) via magnetofection to downregulate PD-L1 expression in cancer cells. We synthesized IONPs of multiple shapes (IONRs (iron oxide nanorods), IONSs (iron oxide nanospheres), and ITOHs (iron oxide truncated octahedrons)), surface-functionalized with polyethyleneimine (PEI) using the ligand exchange method, as gene delivery systems. Under the guidance of an external magnetic field, PEI@IONPs loaded with plasmid DNA (DNA/PEI@IONPs) encoding GFP showed high transfection efficiency at different weight ratios and time points in A549 and MDA-MB-231 cells. Additionally, the DNA/PEI@IONPs with miRNA34a inserts under a static magnetic field resulted in significant knockdown of the PD-L1 gene, as demonstrated via immunoblotting of the PD-L1 protein. Among the three shapes of IONPs, IONRs showed the highest PD-L1 knockdown efficiency. The genetic expression of miRNA34a was also studied using qPCR and it showed high expression of miRNA in cells treated with PEI@IONRs. Flow cytometry and a live/dead assay confirmed apoptosis after transfection with miRNA34a. To conclude, in this paper, a promising transgene carrier with low cost, negligible cytotoxicity, and high transfection efficiency has been successfully established for miRNA gene delivery in the context of cancer immunotherapy.

17.
ACS Nano ; 17(16): 16274-16286, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37530418

RESUMO

Efficient and durable electrocatalysts with superior activity are needed for the production of green hydrogen with a high yield and low energy consumption. Electrocatalysts based on transition metal oxides hold dominance due to their abundant natural resources, regulable physical properties, and good adaptation to a solution. In numerous oxide catalyst materials, ferroelectrics, possessing semiconducting characteristics and switchable spontaneous polarization, have been considered promising photoelectrodes for solar water splitting. However, few investigations noted their potential as electrocatalysts. In this study, we report an efficient electrocatalytic electrode made of a BiFeO3/nickel foam heterostructure, which displays a smaller overpotential and higher current density than the blank nickel foam electrode. Moreover, when in contact with an alkaline solution, the bond between hydroxyls and the BiFeO3 surface induces a large area of upward self-polarization, lowering the adsorption energy of subsequent adsorbates and facilitating oxygen and hydrogen evolution reaction. Our work demonstrates an infrequent pathway of using functional semiconducting materials for exploiting highly efficient electrocatalytic electrodes.

18.
J Colloid Interface Sci ; 650(Pt B): 1698-1714, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37499626

RESUMO

Chemodynamic therapy (CDT) has emerged as a promising strategy for tumor treatment. Nevertheless, the low Fenton catalytic efficiency and the high concentration of glutathione (GSH) in cancer cells largely decline antitumor efficacy of CDT. To self-augment antitumor effect of the CDT by combining with photothermal therapy (PTT), the unique photothermal nanozymes that doubly depleted GSH, and generated massive hydroxyl radicals (·OH) in the hyperthermia/acidity-activated manner were developed. Through the coordination of Fe3+ ions with PEGylated chitosan (PEG-CS)-modified polydopamine (PDA) nanoparticles, the attained Fe3+@PEG-CS/PDA nanozymes showed outstanding colloidal stability, photothermal conversion efficiency and acidity-triggered Fe3+ release. By GSH-mediated valence states transition of Fe3+ ions and Michael reaction between GSH and quinone-rich PDA, the nanozymes sufficiently executed dual depletion of GSH with the elevated temperature.Under mimic tumor acidity and near-infrared (NIR) irradiation condition, the endocytosed nanozymes effectively converted intracellular H2O2 into toxic ·OH upon amplified Fenton reaction, thereby potently killing 4T1 cancer cells and RAW 264.7 cells. Importantly, the nanozymes prominently suppressed 4T1 tumor growth in vivo and metastasis of cancer cells by CDT/PTT combination therapy without significant systemic toxicity. Our study provides novel visions in design of therapeutic nanozymes with great clinical translational prospect for tumor treatment.


Assuntos
Quitosana , Nanopartículas , Neoplasias , Humanos , Radical Hidroxila , Peróxido de Hidrogênio , Terapia Combinada , Glutationa , Terapia Fototérmica , Linhagem Celular Tumoral , Neoplasias/terapia
19.
Int J Biol Macromol ; 220: 250-257, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35981673

RESUMO

Although tannins are widely distributed in broad beans and alfalfa, the pea aphid (Acyrthosiphon pisum) can still destroy them. The ATP binding cassette (ABC) transporters participate in the metabolism of plant secondary metabolites and pesticides in insects. However, whether ABC transporter genes play a role in the metabolism of tannins in the pea aphid is unclear. Here, we found that verapamil (an ABC transporter inhibitor) significantly increased the mortality of tannic acid to pea aphid, which indicated that ABC transporter gene was related to the metabolism of tannic acid by pea aphid. Then, we identified 54 putative ABC transporter genes from the genome database of A. pisum. These genes were divided into eight subfamilies, ApABCA to ApABCH, of which subfamily G has the largest number of genes with 19, followed by the subfamily C with 14. RT-qPCR results show that the expression levels of ApABCA2, ApABCC7, ApABCG2, and ApABCG3 were highly expressed in the first instar, while those of ApABCA3, ApABCG6, ApABCG7, ApABCH3, and ApABCH4 were highly expressed in adults. Furthermore, transcription levels of many ABC transporter genes were induced by tannic acid. Especially, ApABCG17 and ApABCH2 were obviously induced after being exposed to tannic acid. Meanwhile, knockdown of ApABCG17 by RNA interference resulted in increased sensitivity of pea aphid to tannic acid. These results suggest that ApABCG17 may be involved in tannic acid metabolism in pea aphid. This study will help us to understand the mechanism of tannic acid metabolism in pea aphid, and provides a basis for further research on the physiological function of ABC transporter genes in pea aphid.


Assuntos
Afídeos , Praguicidas , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Afídeos/genética , Medicago sativa , Pisum sativum/metabolismo , Praguicidas/metabolismo , Taninos/metabolismo , Verapamil/metabolismo
20.
J Pharmacol Exp Ther ; 337(1): 102-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21205917

RESUMO

The etiology of vitamin B(6) depletion in inflammation remains unknown. Hepatic vitamin B(6) decreased in adrenalectomized rats, and such reductions were restored by an acute muscle injection of a very high dose of glucocorticoids. We tested the hypothesis that long-term prednisolone treatment for treating inflammation restores vitamin B(6) status by induction of tissue B6 metabolic enzymes. Two independent in vivo models were used. Lewis rats and C57BL/6J mice received prednisolone regimens that reflected clinical prednisolone uses in treating human inflammation. We found: 1) prednisolone increased circulating B6 vitamer pyridoxal 5'-phosphate (PLP; bioactive B6 vitamer), pyridoxal (PL), and 4-pyridoxic acid without altering vitamin B(6) excretion; 2) prednisolone simultaneously induced the hepatic PLP-synthesizing enzyme pyridoxine kinase (PDXK) and pyridoxamine-5'-phosphate oxidase (PMPO) and suppressed PLP catabolic enzyme pyridoxal-5'-phosphate phosphatase (PDXP); and 3) elevations in circulating PL were caused by its release from the liver, not by PLP dephosphorylation (PDXP was suppressed and alkaline phosphatase was unaltered). We conclude that long-term prednisolone treatments promoted hepatic bioactive vitamin B(6) synthesis by inducing the synthesizing enzymes PDXK and PMPO and simultaneously suppressing the catabolic enzyme PDXP. Prednisolone increased circulating B6 vitamer without altering urinary B6 excretion. As the major form of vitamin B(6) across cell membrane, elevated circulating PL may facilitate the cellular uptake and utilization of B6. The elevated plasma PLP may increase vitamin B(6) supply to tissues with a higher B6 demand during inflammation. Results from two independent in vivo models suggested a potential advantage of clinical prednisolone use in treating inflammation with respect to vitamin B(6) status.


Assuntos
Prednisolona/administração & dosagem , Vitamina B 6/biossíntese , Animais , Feminino , Mediadores da Inflamação/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Endogâmicos Lew , Fatores de Tempo , Distribuição Tecidual/efeitos dos fármacos , Distribuição Tecidual/fisiologia , Vitamina B 6/sangue
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