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1.
Talanta ; 230: 122294, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33934766

RESUMO

The determination approaches of Fe (Ⅲ) in biological samples were developed by a novel water-soluble silicon nanoparticles (SiNPs). The SiNPs were synthesized by a facile microwave-assisted method, and simultaneously featured strong blue fluorescence (photoluminescence quantum yield: 25.2%), long lifetime (~13.29 ns) and good photo-stability. The fluorescence intensities of SiNPs were gradually quenched with Fe (Ⅲ) concentration increasing from 2.0 to 50 µmol/L. The detection limit of the established method was 0.56 µmol/L and the precision for eleven replicate detections of 20 µmol/L Fe (Ⅲ) was 3.2% (relative standard deviation, RSD). The spiked recoveries were 99.0%-104.5%. Results of the lifetime decay and cyclic voltammetry (CV) evidenced that the electron transfer was responsible for the fluorescence quenching mechanism of SiNPs and Fe (Ⅲ). Moreover, the SiNPs were successfully applied in the determination of Fe(Ⅲ) in different environmental waters and human serum. Finally, the resulting SiNPs exhibited the green fluorescence in HeLa cells as the optical probe.

2.
J Stud Alcohol Drugs ; 82(2): 197-203, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33823966

RESUMO

OBJECTIVE: Inhibitory deficits contribute to impulsive drug-seeking behavior in individuals with methamphetamine use disorder (MUD). Whether abstinent individuals with MUD exhibit greater cognitive disinhibition when the suppressed response is associated with drug-related images is not fully known. This study evaluated the potency of drug-associated cue exposure in this process. METHOD: We recruited 54 abstinent men with MUD and 46 healthy control (HC) subjects to complete a novel go/no-go task in which drug-associated cues were presented in 240 trials. RESULTS: Upon exposure to drug-associated cues, the numbers of commission errors increased significantly only in the abstinent MUD group (p < .001), and the abstinent MUD group produced higher levels of commission errors than the HC group (p = .009). When drug-associated cues were not available (in scrambled trials), the abstinent MUD group produced similar levels of commission errors when compared with the HC group (p = .336). The reaction times in drug cue exposure trials were longer than in scrambled trials across groups (p < .001), whereas the abstinent MUD group produced shorter reaction times than HCs, regardless of trial conditions (p = .004). CONCLUSIONS: The novel go/no-go task is a useful method for detecting impulsivity in abstinent individuals with MUD. Cue exposure triggers impairment of inhibitory control in individuals with MUD at abstinence.

3.
J Phys Chem A ; 2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33904306

RESUMO

We performed cryogenic ion mobility-mass spectrometry (IM-MS) to study conformations of dibenzo-crown-ether complexes with Na+ and K+ ions at 86 K in the gas phase. Four dibenzo-crown-ethers (dibenzo-18-crown-6, dibenzo-21-crown-7, dibenzo-24-crown-8, and dibenzo-30-crown-10) with different cavity ring sizes were investigated. For dibenzo-18-crown-6 complexes with Na+ and K+, only one type of conformer was assigned by comparing the experimental collision cross sections with those predicted theoretically for candidate structures. In this conformer, the distance between two benzene rings in the complexes was long due to the open form of the dibenzo-18-crown-6. This open conformer was consistent with the previous laser spectroscopic studies of the cold complex ions in the gas phase. For dibenzo-21-crown-7 and dibenzo-24-crown-8 complexes with Na+ and K+, two types of conformers were clearly separated by IM-MS. These two conformer types were assigned to "open" and "closed" forms in which benzene-benzene distances were long and short, respectively. Observed relative abundances of the open and closed conformers qualitatively agreed with the Boltzmann distribution using Gibbs energies of the conformers calculated by quantum chemical calculations. For the Na+(dibenzo-30-crown-10) complex, open and closed conformers were also observed in IM-MS. On the other hand, only the closed conformer was observed for the K+(dibenzo-30-crown-10) complex. This closed conformer was similar to the "wraparound" structure, which was proposed in the previous studies in the solution. In conclusion, the closed conformers were formed by the deformation of flexible crown ethers with large cavity ring sizes. In addition, the diameter of the K+ ion was suitable to form the closed conformer by deformation of the molecular structure of dibenzo-30-crown-10.

4.
Oncologist ; 2021 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-33896090

RESUMO

The addition of trastuzumab to chemotherapy regimen is standard of care for human epidermal growth factor receptor 2 (HER2)-positive advanced gastric cancer; however, most patients eventually acquire trastuzumab resistance. Although some resistance mechanisms to trastuzumab-based regimens have been proposed, further understanding is required for developing therapeutic strategies to overcome the resistance. In the present work, we attempted to determine the possible resistance mechanism to trastuzumab in a patient with HER2-positive stage IV gastric adenocarcinoma. In this study, we first report the nucleotide change c.1899-1G>A at the intron 15 acceptor splice site promoting exon 16 deletion of HER2 as the potential mechanism of trastuzumab resistance in HER2-positive gastric adenocarcinoma. KEY POINTS: The combination of trastuzumab with chemotherapy is considered the standard therapy for HER2-positive advanced gastric cancer (GC), but most of the patients eventually acquire trastuzumab resistance. The mechanisms of resistance to trastuzumab in GC are poorly characterized. To the best of our knowledge, our study is the first to implicate HER2 c.1899-1G>A, which results in exon 16 skpping, as the acquired resistance mechanism to trastuzumab in HER2-positive gastric adenocarcinoma. Our work provides insights into the potential molecular mechanism of trastuzumab resistance, which is crucial in developing effective therapeutic strategies for HER2-positive GC patients refractory to trastuzumab.

5.
Zhongguo Gu Shang ; 34(4): 368-72, 2021 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-33896139

RESUMO

OBJECTIVE: To investigate expression of Semaphorin 3A in rats after spinal cord injury and explore possible mechanism of inhibiting of axonal regeneration after SCI. METHODS: Forty healthy female SD rats, 8 weeks old, weighing (210.00±9.88) g, were randomly divided into control group(20 rats in group A) and model group(20 rats in group B). In control group, removal of T10 lamina and partial removal of T9 and T11 lamina were performed, and no further operation was performed on spinal cord (pseudo operation). In model group, the total T10 and partial T9, T11 partial lamina were incised and the spinal cord transection was performed to create animal models of spinal cord injury. The rats were perfused and spinal cord tissue obtained at 3, 7, 14, 28 and 42 days after surgery (4 rats in each group at each time point), respectively, and then HE staining was performed. Meanwhile, the expression of Semaphoring 3A was detected in accordance with the protocol of SP kit. RESULTS: After a simple spinal cord transection injury, hemorrhagic necrosis, localized edema, neurodegeneration, necrosis, and cyst formation occurred in the injured area, and glial scar formation occurred in glial cells. Semaphorin 3A expression levels in control group was low in the gray matter area. There was no expression of Semaphorin 3A in the injured area of spinal cord injury in model group 3 days after operation. On the 14th day, the expression of Semaphorin 3A in the injured area of spinal cord injury increased significantly and was at a high level. On the 28th day, the expression of Semaphorin 3A was moderate. On the 42th day, the positive expression of Semaphorin 3A returned to normal level. CONCLUSION: The increased expression of Semaphorin 3A after spinal cord injury may be one of the mechanisms that inhibit axonal regeneration.


Assuntos
Semaforina-3A , Traumatismos da Medula Espinal , Animais , Feminino , Ratos , Ratos Sprague-Dawley , Semaforina-3A/genética , Medula Espinal , Traumatismos da Medula Espinal/genética
6.
Environ Technol ; : 1-14, 2021 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-33843473

RESUMO

The effects of initial total phosphorus (TP) concentration, current density, conductivity and initial pH value on the removal rate of TP and energy consumption, as well as the behaviour and mechanism of phosphorus removal, were investigated by sinusoidal alternating current coagulation (SACC). The flocs produced by SACC were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy FTIR and X-ray photo electron spectroscopy. The thermodynamic and kinetic behaviours of phosphorus removal by iron sol adsorption were also studied in detail. In a self-made SACC reactor equipped with five sets of parallel iron electrodes spacing 10 mm, the removal rate of TP reached 90.9% for a pH 7.0 wastewater with 5 mg dm-3 TP (κ = 800 µS cm-1) after being treated for 60 min by applying 2.12 mA cm-2 sinusoidal alternating current. Compared with direct current coagulation (DCC), SACC exhibits a higher removal efficiency of phosphorus due to the stronger adsorption of the produced flocs. It was found that the adsorption in the SACC process follows pseudo-second-order kinetic with the involvement of the intra-particle model. The adsorption of iron sol to phosphorus was an endothermic and spontaneous process, and its adsorption behaviour can be characterized with Langmuir and Redlich-Peterson isothermal adsorption models. SACC may be employed for the treatment of more complex wastewater combined with biological and/or electrochemical techniques.

8.
Poult Sci ; 100(4): 101014, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33676096

RESUMO

The chicken egg yolk, which is abundant with lipids, proteins, and minerals, is the major nutrient resource for the embryonic development. In fact, the magnitude and type of yolk nutrients are dynamically changed during the chicken embryogenesis to meet the developmental and nutritional requests at different stages. The yolk nutrients are metabolized and absorbed by the yolk sac membrane and then used by the embryo or other extraembryonic tissues. Thus, understanding the metabolites in the yolk helps to unveil the developmental nutritional requirements for the chicken embryo. In this study, we performed ultra high performance liquid chromatography/tandem mass spectrometry (UHPLC-MS/MS) analysis to investigate the change of metabolites in the egg yolk at embryonic (E) 07, E09, E11, E15, E17, and E19. The results showed that 1) the egg yolk metabolites at E07 and E09 were approximately similar, but E09, E11, E15, E17, and E19 were different from each other, indicating the developmental and metabolic change of the egg yolk; and 2) most of the metabolites were annotated in amino acid metabolism pathways from E11 to E15 and E17 to E19. Especially, arginine, lysine, cysteine, and histidine were continuously increased during the embryonic development, probably because of their effects on the growth promotion and oxidative stress amelioration of the embryo. Interestingly, the ferroptosis was found as one of major processes occurred from E15 to E17 and E17 to E19. Owing to the upregulated expression of acyl-CoA synthetase long-chain family member 4 detected in the yolk sac, we assumed that the ferroptosis of the yolk sac was perhaps caused by the accumulation of reactive oxygen species, which was induced by the large amount of polyunsaturated fatty acids and influx of iron in the yolk. Our findings might offer a novel understanding of embryonic nutrition of broilers according to the developmental changes of metabolites in the egg yolk and may provide new ideas to improve the health and nutrition for prehatch broiler chickens.

9.
Artigo em Inglês | MEDLINE | ID: mdl-33685900

RESUMO

Plasmodium falciparum from the Greater Mekong subregion has evolved resistance to the artemisinin-based combination therapy dihydroartemisinin and the partner drug piperaquine. To monitor the potential westward spread or independent evolution of piperaquine resistance, we evaluated the in vitro susceptibility of 120 P. falciparum isolates collected at the China-Myanmar border during 2007-2016. The parasite isolates displayed a relatively wide range of piperaquine susceptibility estimates. While 56.7% of the parasites showed bimodal drug response curves, all but five generated area-under-the-curve (AUC) estimates consistent with a susceptible phenotype. Using the piperaquine survival assay (PSA), 5.6% parasites showed reduced susceptibility. Of note, parasites from 2014-2016 showed the highest AUC value and the highest proportion with a bimodal curve, suggesting falling effectiveness in these later years. Unsupervised K-mean analysis of the combined data assigned parasites into three clusters and identified significant correlations between IC50, IC90, and AUC values. No parasites carried the E415G mutation in a putative exo-nuclease, new mutations in PfCRT, or amplification of the plasmepsin 2/3 genes, suggesting mechanisms of reduced piperaquine susceptibility that differ from those described in other countries of the region. The association of increased AUC, IC50, and IC90 values with major PfK13 mutations (F446I and G533S) suggests that piperaquine resistance may evolve in these PfK13 genetic backgrounds. Additionally, the Pfmdr1 F1226Y mutation was associated with significantly higher PSA values. Further elucidation of piperaquine resistance mechanisms and continuous surveillance are warranted.

10.
Proc Natl Acad Sci U S A ; 118(15)2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33766889

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) research and antiviral discovery are hampered by the lack of a cell-based virus replication system that can be readily adopted without biosafety level 3 (BSL-3) restrictions. Here, the construction of a noninfectious SARS-CoV-2 reporter replicon and its application in deciphering viral replication mechanisms and evaluating SARS-CoV-2 inhibitors are presented. The replicon genome is replication competent but does not produce progeny virions. Its replication can be inhibited by RdRp mutations or by known SARS-CoV-2 antiviral compounds. Using this system, a high-throughput antiviral assay has also been developed. Significant differences in potencies of several SARS-CoV-2 inhibitors in different cell lines were observed, which highlight the challenges of discovering antivirals capable of inhibiting viral replication in vivo and the importance of testing compounds in multiple cell culture models. The generation of a SARS-CoV-2 replicon provides a powerful platform to expand the global research effort to combat COVID-19.


Assuntos
Antivirais/farmacologia , Ensaios de Triagem em Larga Escala/métodos , Replicon/efeitos dos fármacos , /efeitos dos fármacos , Células A549 , Animais , Chlorocebus aethiops , Células HEK293 , Humanos , Replicon/genética , Células Vero , Replicação Viral/efeitos dos fármacos
11.
Zhongguo Gu Shang ; 34(1): 33-9, 2021 Jan 25.
Artigo em Chinês | MEDLINE | ID: mdl-33666017

RESUMO

OBJECTIVE: To explore the short-term clinical efficacy of single-stage cervical spondylotic radiculopathy (CSR) between the minimally invasive Key-hole technique and anterior cervical Zero profile intervertebral fusion system (Zero-P). METHODS: A retrospective analysis was performed on 45 patients who underwent surgical treatment for CSR from January 2017 to January 2020, including 21 in Key hole group (12 males and 9 females), followed up for 10-22(13.2±2.3) months;24 cases in Zero-P group (14 males and 10 females), and the follow up period was 10 to 23(12.7±1.9) months. Perioperative conditions (incision length, intraoperative blood loss, operation time, length of hospital stay, and complications) were compared between two groups, and X-rays of cervical spine before and after surgery and at the final follow-up were taken to analyzed curvature of the cervical spine, visual analogue scale(VAS) of pain before and after surgery, Oswestry Disability Index(ODI) and Japanese Orthopaedic Association (JOA) score of cervical spine were recorded to evaluate clinical efficacy. RESULTS: In Key-hole group and Zero-P group, the surgical incision length, intraoperative blood loss, operation time, final follow-up Cobb angle and immediate postoperative VAS score respectively were (1.2±0.2) cm, (5.3±0.3) cm;(35.3±9.7) ml, (120.2±13.5) ml;(56.4±11.3) min, (90.6±12.6) min;(3.2±3.9)°, (7.3±3.8)°;(2.8±1.2)points, (3.8±1.1) points;the Zero-P group was larger than the Key hole group, with statistical significance(P<0.05) . There were no statistically significant difference in length of hospital stay, ODI and JOA scores between two groups (P>0.05). After the follow-up, 1 case of neurostimulation symptoms in Key-hole group was relieved by conservative treatment, 2 cases improved after reoperation due to recurrence of cervical disc herniation;2 cases of neurostimulation symptoms in Zero-P group, 2 cases of throat discomfort, and 1 case dural tears were all relieved by conservative treatment. CONCLUSION: The cervical spine Key-hole technology is similar to the anterior cervical Zero-P system in the treatment of CSR. The Key-hole technique has certain advantages in incision length, intraoperative blood loss, and operation time. It is a safe, effective and can be widely used cervical spine surgery method.


Assuntos
Radiculopatia , Fusão Vertebral , Espondilose , Estudos de Casos e Controles , Vértebras Cervicais/cirurgia , Feminino , Humanos , Masculino , Radiculopatia/cirurgia , Estudos Retrospectivos , Espondilose/cirurgia , Resultado do Tratamento
12.
Zhongguo Zhong Yao Za Zhi ; 46(1): 162-170, 2021 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-33645066

RESUMO

To study the time-toxicity relationship and mechanism of Gardeniae Fructus extract on the hepatoxicity in rats. Rats were randomly divided into C group(0 day), D5 group(5 days), D12 group(12 days), D19 group(19 days), and D26 group(7 days recovery after 19 days of administration). The rats in normal group received normal saline through intragastric administration, and the rats in other groups received 10 g·kg~(-1 )Gardeniae Fructus extract through intragastric administration. After the final administration, the livers were collected. Hematoxylin-eosin staining was used to observe the histopathological changes in the liver tissue. Total liver proteins were extracted for proteomic analysis, detected by the Nano-ESI liquid-mass spectrometry system and identified by Protein Disco-very software. SIEVE software was used for relative quantitative and qualitative analysis of proteins. The protein-protein interaction network was constructed based on STRING. Cytoscape software was used for cluster analysis of differential proteins. Kyoto encyclopedia of genes and genomes(KEGG) database was used to perform enrichment signal pathway analysis. Pearson correlation analysis was performed for the screened differential protein expression and liver pathology degree score. The results showed that the severity of liver injury in D5, D12 and D19 groups was significantly higher than that in group C. The degree of liver damage in D5 group was slightly higher than that in D12 and D19 groups, with no significant difference between group D26 and group C. Totally 147 key differential proteins have been screened out by proteomics and mainly formed 6 clusters, involving in drug metabolism pathways, retinol metabolism pathways, proteasomes, amino acid biosynthesis pathways, and glycolysis/gluconeogenesis pathways. The results of Pearson correlation analysis indicated that differential protein expressions had a certain temporal relationship with the change of liver pathological degree. The above results indicated that the severity of liver damage caused by Gardeniae Fructus extract did not increase with time and would recover after drug with drawal. The above pathways may be related to the mechanism of liver injury induced by Gardeniae Fructus extract.


Assuntos
Medicamentos de Ervas Chinesas , Gardenia , Animais , Medicamentos de Ervas Chinesas/toxicidade , Frutas , Fígado , Proteômica , Ratos , Transdução de Sinais
13.
Lab Invest ; 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33649466

RESUMO

The key pathophysiological process leading to heart failure is cardiac remodeling, a term referring to cardiac hypertrophy, fibrosis, and apoptosis. We explored circadian rhythm disruption and calcium dyshomeostasis in cardiac remodeling and investigated the cardioprotective effect of choline. The experiments were conducted using a model of cardiac remodeling by abdominal aorta coarctation (AAC) in Sprague-Dawley rats. In vitro cardiomyocyte remodeling was induced by exposing neonatal rat cardiomyocytes to angiotensin II. The circadian rhythms of the transcript levels of the seven major components of the mammalian clock (Bmal1, Clock, Rev-erbα, Per1/2, and Cry1/2) were altered in AAC rat hearts during a normal 24 h light/dark cycle. AAC also upregulated the levels of proteins that mediate store-operated Ca2+ entry/receptor-operated Ca2+ entry (stromal interaction molecule 1 [STIM1], Orai1, and transient receptor potential canonical 6 [TRPC6]) in rat hearts. Moreover, choline ameliorated circadian rhythm disruption, reduced the upregulated protein levels of STIM1, Orai1, and TRPC6, and alleviated cardiac dysfunction and remodeling (evidenced by attenuated cardiac hypertrophy, fibrosis, and apoptosis) in AAC rats. In vitro analyses showed that choline ameliorated calcium overload, downregulated STIM1, Orai1, and TRPC6, and inhibited thapsigargin-induced store-operated Ca2+ entry and 1-oleoyl-2-acetyl-sn-glycerol-induced receptor-operated Ca2+ entry in angiotensin II-treated cardiomyocytes. In conclusion, choline attenuated AAC-induced cardiac remodeling and cardiac dysfunction, which was related to amelioration of circadian rhythm disruption and attenuation of calcium-handling protein defects. Modulation of vagal activity by choline targeting the circadian rhythm and calcium homeostasis may have therapeutic potential for cardiac remodeling and heart failure.

14.
J Cell Mol Med ; 25(8): 3976-3990, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33638619

RESUMO

Ovarian hyperstimulation syndrome (OHSS) is one of the most dangerous iatrogenic complications in controlled ovarian hyperstimulation (COH). The exact molecular mechanism that induces OHSS remains unclear. In recent years, accumulating evidence found that exosomal miRNAs participate in many diseases of reproductive system. However, the specific role of miRNAs, particularly the follicular fluid-derived exosomal miRNAs in OHSS remains controversial. To identify differentially expressed follicular fluid exosomal miRNAs from OHSS and non-OHSS patients, the analysis based on miRNA-sequence was conducted. The levels of 291 miRNAs were significantly differed in exosomes from OHSS patients compared with normal control, and exosomal miR-27 was one of the most significantly down-regulated miRNAs in the OHSS group. By using MiR-27 mimic, we found it could increase ROS stress and apoptosis by down-regulating the expression of p-ERK/Nrf2 pathway by negatively regulating SPRY2. These data demonstrate that exosomal miRNAs are differentially expressed in follicular fluid between patients with and without OHSS, and follicular fluid exosomal miR-27 may involve in the pathological process of OHSS development.

15.
J Microbiol Biotechnol ; 31(4): 550-558, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33622994

RESUMO

Lactobacillus kefiranofaciens contains two types of ß-galactosidase, LacLM and LacZ, belonging to different glycoside hydrolase families. The difference in function between them has been unclear so far for practical application. In this study, LacLM and LacZ from L. kefiranofaciens ATCC51647 were cloned into constitutive lactobacillal expression vector pMG36e, respectively. Furtherly, pMG36n-lacs was constructed from pMG36e-lacs by replacing erythromycin with nisin as selective marker for food-grade expressing systems in Lactobacillus plantarum WCFS1, designated recombinant LacLM and LacZ respectively. The results from hydrolysis of o-nitrophenyl-ß-galactopyranoside (ONPG) showed that the ß-galactosidases activity of the recombinant LacLM and LacZ was 1460% and 670% higher than that of the original L. kefiranofaciens. Moreover, the lactose hydrolytic activity of recombinant LacLM was higher than that of LacZ in milk. Nevertheless, compare to LacZ, in 25% lactose solution the galacto-oligosaccharides (GOS) production of recombinant LacLM was lower. Therefore, two ß-galactopyranosides could play different roles in carbohydrate metabolism of L. kefiranofaciens. In addition, the maximal growth rate of two recombinant strains were evaluated with different temperature level and nisin concentration in fermentation assay for practical purpose. The results displayed that 37°C and 20-40 U/ml nisin were the optimal fermentation conditions for the growth of recombinant ß-galactosidase strains. Altogether the food-grade Expression system of recombinant ß-galactosidase was feasible for applications in the food and dairy industry.

16.
Vasc Endovascular Surg ; : 1538574421996948, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33622206

RESUMO

Diffuse pulmonary arteriovenous malformations (PAVMs) are defined as arteriovenous malformations (AVMs) involving subsegmental, segmental, or both types of arteries in at least 1 lung lobe and are more extensive than multiple PAVMs. Diffuse PAVMs involving systemic arterial shunts are very rare. We describe a rare case, in which diffuse PAVMs involving systemic arterial shunts were successfully treated with coil embolization.

17.
J Hazard Mater ; 412: 125249, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33548789

RESUMO

In this work, we innovatively synthesized homochiral fluorescence nano molecularly imprinted polymers (D-MIP) with dual affinity (metal ion affinity and homochiral affinity) for the specific separation and detection of L-penicillamine (L-PA), which is a core-shell structure with a SiO2-covered CDs core and an imprinted layer with L-PA cavities. A switch for fluorescence response was built by chelating grafted Cu2+, what's more, the imprinted L-PA was pre immobilized by Cu2+ to form the directional imprinting with predetermined spatial structure. More importantly, the homochiral affinity of D-galactose in homochiral molecularly imprinted polymers (D-MIP) greatly enhanced the selective adsorption of L-PA, and D-MIP showed a high selectivity factor (α) of 3.45, which is 1.9 times that of the non-homochiral molecularly imprinted polymers (MIP). Meanwhile, D-MIP exhibited a high enantiomeric excess (ee) value of 56% for separation of racemic PA. Additionally, a high sensitive and selective method was established for the detection of L-PA.

18.
Int J Med Sci ; 18(1): 29-41, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33390771

RESUMO

Rationale: Previous studies of coronavirus disease 2019 (COVID-19) were mainly focused on cross-sectional analysis. In this study, we sought to evaluate the dynamic changes of immunological and radiographic features, and the association with the outcome of pulmonary lesions in COVID-19 patients. Methods: Peripheral blood samples and radiographic data were collected longitudinally for up to 8 weeks from 158 laboratory-confirmed COVID-19 patients. The chest computed tomography (CT) scans were scored based on a semi-quantification assessment according to the extent of pulmonary abnormalities; the temporal change of the immunological and radiographic features was analyzed. Results: Compared with mild and moderate patients, severe patients had significantly decreased counts of lymphocytes, CD4+ T cells, CD8+ T cells, and CD19+ B cells but dramatically elevated counts of neutrophils and levels of interleukin (IL)-6. Sequential monitoring showed a sustained increase in lymphocytes counts and significantly decreased levels of IL-6 in severe patients during the disease course. Notably, patients with persistent pulmonary lesions (CT score ≥ 5 in week 8) showed high levels of IL-6 during the follow-up period, compared with those with recovery lesions (CT score < 5 in week 8). More importantly, the peak expression of IL-6 prior to the aggravated lung injury was mainly found in patients with persistent lesions, and multivariate analysis showed that IL-6 level upon admission was an independent factor associated with the persistent pulmonary injury. Conclusion: Prolonged elevation of IL-6 is associated with persistent pulmonary lesions in COVID-19 patients. Sequential monitoring and timely intervention of IL-6 may favor the clinical management of COVID-19.


Assuntos
/imunologia , Interleucina-6/sangue , Lesão Pulmonar/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , /complicações , Feminino , Humanos , Estudos Longitudinais , Lesão Pulmonar/diagnóstico por imagem , Lesão Pulmonar/virologia , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Radiografia Torácica , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Adulto Jovem
20.
J Mater Chem B ; 9(4): 1049-1058, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33399610

RESUMO

It is difficult for drug delivery systems to release drugs as expected, often leading to undesired side effects. To solve this problem, a CuS@MSN/DOX@MnO2@membrane (CMDMm) was reasonably designed. It was introduced to release the drug by a double response, similar to using two keys to open two locks at the same time for one door. CuS@MSN was used as a photothermal therapy (PTT) material and carrier, and then the surface of CuS@MSN/DOX was sealed by MnO2 to prevent drug release in advance. MnO2 could be reduced and degraded in a tumor microenvironment. It was applied in MR imaging due to the T1 magnetism of Mn2+ following the reduction of MnO2. Finally, the 4T1 cell membrane was extracted and coated onto the surface of CuS@MSN/DOX@MnO2, which served as a target for 4T1 tumor cells. A noteworthy phenomenon was that the fluorescence of DOX was quenched by the coordination between DOX and CuS, and this greatly improved the interaction between DOX and CuS@MSN. However, the coordination was weakened when DOX was protonated in a tumor microenvironment (∼pH 5.0), leading to the release of DOX and fluorescence recovery. The drug release experiments showed that the release efficiency was higher at pH 5.0 with 10 mmol L-1 GSH. Through in vitro laser confocal imaging, it was successfully observed that DOX was reliably released in specific tumor cells according to the fluorescence recovery, and that there was no leakage in other cells. In short, effective double response drug release was successfully confirmed.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Cobre/farmacologia , Doxorrubicina/farmacologia , Compostos de Manganês/farmacologia , Nanopartículas/química , Óxidos/farmacologia , Animais , Antibióticos Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cobre/química , Doxorrubicina/química , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/patologia , Compostos de Manganês/química , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Óxidos/química , Tamanho da Partícula , Propriedades de Superfície
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