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The taste of oral dosage forms has become a critical factor affecting the drug compliance and adherence to the treatment, and clinical application of the drug product may seriously restricted due to its bad taste. On the basis of the statement for the basic principle and specific performance of existing instruments, the application progress of electronic tongue on drug taste evaluation is addressed in detail. In view of its objective, fatigue-free, less harmful and accurate advantages, electronic tongue has been widely and meaningfully applied in the aspects of bitterness masking, and quality assessment and assurance of drug products. In addition, the reasons limiting the popularization of electronic tongue are mentioned in the paper, and some suggestions might be useful to enlarge the further application in the future.
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Electronic tongue is one kind of bionic detection technologies, which can objectively reflect the taste of drugs based on electrochemical principle. In this paper, the development histories of electronic tongue both of potential type and voltammetry type were introduced, including their detection principles and key innovation technologies. In order to comprehensively improve the understanding of electronic tongue, its technological progresses, such as the study of dedicated sensors or biosensors for specific tastes, and the development of miniaturized or hybrid devices, were also discussed in detail. And the challenges and countermeasures in the application of electronic tongue were analyzed to provide some suggestions for its further technology promotion.
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ObjectiveTo investigate the effect of liquiritigenin (LG) on intestinal flora in menopausal APP/PS1 mice. MethodsA total of forty 3-month-old female APP/PS1 mice were randomly divided into sham surgery group (n=20) and ovariectomy group (n=20). Seven days after surgery, the ovariectomy group was randomly divided into ovariectomy control group (OVX, n=10), ovariectomy + liquiritigenin treatment group (OVX + LG, n=10), and the sham surgery group was randomly divided into liquiritigenin treatment group (LG, n=10) and reagent control group (Sham, n=10), and ten C57BL/6J mice were taken as WT group. The dose of LG group and OVX + LG group was 30 mg•kg-1•d-1. After 90 days of drug treatment, fecal samples were gathered, genomes were extracted, and intestinal flora were analyzed by 16S rDNA Amplicon Sequencing. Morris water maze was performed to evaluate learning and memory abilities of mice. Immunofluorescence was used to observe the deposition of senile plaques (SP) in the brain of mice. ResultsThe results of water maze showed that LG significantly improved the learning memory ability of APP/PS1 mice with/without OVX (P<0.05), and reduced the number of SPs in the brain of APP/PS1 mice with/without OVX, and the differences were statistically significant (P<0.000 1). 16s rDNA sequencing analysis of the relative abundance of gut microbiota proved that LG treatment significantly increased the relative abundance of Firmicutes and Lactobacillus (P<0.05) and reduced the relative abundance of harmful bacteria belong to Bacteroidetes (P<0.05) in APP/PS1 mice intestines with/without menopause. After LG treatment, the relative abundance of Allobaculun elevated in the intestines of APP/PS1 mice, while declined in the intestines of menopausal APP/PS1 mice, but the difference was not statistically significant. LEfSe analysis revealed the bacteria with the most differential abundance of the gut microbiota of WT mice were Firmicutes, Bacillus, and Lactobacillales (P<0.05); Lactobacillus reuteri had a greater influence on the LG group (P<0.05); Bacteroidia, Bacteroidales and Bacteroides gathered in the intestines of mice in the Sham group (P<0.05). Firmicutes and Allobaculum were the dominant in the WT group (P<0.05); Bacteroides, Bacteroidia and Bacteroidales were more abundant in the Sham group(P<0.05); Bacterroidaceae and Bacteroides had the most differential abundances in the OVX group (P<0.05); Lactobacillaceae and Lactobacillus were more abundant in the intestines in the OVX + LG group (P<0.05). ConclusionLG could improve the ratio of beneficial and harmful bacteria in the intestines of APP/PS1 mice before and after menopause. Liquiritigenin treatment showed consistent variations in intestinal flora in APP/PS1 mice with or without ovariectomy. It is presumed that menopausal APP/PS1 mice have lipid metabolism disorders which requires further study.
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Objective:To explore the configuration conditions and type-selections of positron emission tomography/computed tomography(PET/CT)and positron emission tomography/magnetic resonance(PET/MR)system under the national new policies during the 14th Five-Year Plan period,so as to provide references for configuration and type-selection of PET/CT and PET/MR equipment of medical institutions.Methods:According to the management polices of relevant configurations of PET/CT and PET/MR,which included configuration licensing,use management and configuration plan,and which were issued by China 14th Five-Year Plan,as well as the development trend and characteristics of PET/CT and PET/MR new techniques,the configuration conditions and type-selection plan of PET/CT and PET/MR equipment were analyzed.Results:Under the new polices during national 14th Five-Year Plan,medical institutions should configure PET/CT and PET/MR depended on the condition of institutions,personnel condition,work basis,the supporting facilities and other conditions,and should select the type of PET/CT and PET/MR which can meet the requirements of medical institutions depended on the technique parameters and performance indicators of PET/CT and PET/MR.Conclusions:Since the 14th Five-Year Plan,there were significant changes in the new policies related to the configurations of PET/CT and PET/MR compared to previous policies.The medical institutions should apply configurations and use PET/CT and PET/MR as new requirement,and configure the PET/CT and PET/MR equipment and conduct type-selection of them as various requirements of each institution.
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Objective: To investigate the scientificity and feasibility of the ten-fold rehydration formula for emergency resuscitation of pediatric patients after extensive burns. Methods: A retrospective observational study was conducted. The total burn area of 30%-100% total body surface area (TBSA) and body weight of 6-50 kg in 433 pediatric patients (250 males and 183 females, aged 3 months to 14 years) with extensive burns who met the inclusion criteria and admitted to the burn departments of 72 Class A tertiary hospitals were collected. The 6 319 pairs of simulated data were constructed after pairing each body weight of 6-50 kg (programmed in steps of 0.5 kg) and each total burn area of 30%-100% TBSA (programmed in steps of 1%TBSA). They were put into three accepted pediatric rehydration formulae, namely the commonly used domestic pediatric rehydration formula for burn patients (hereinafter referred to as the domestic rehydration formula), the Galveston formula, and the Cincinnati formula, and the two rehydration formulae for pediatric emergency, namely the simplified resuscitation formula for emergency care of patients with extensive burns proposed by the World Health Organization's Technical Working Group on Burns (TWGB, hereinafter referred to as the TWGB formula) and the pediatric ten-fold rehydration formula proposed by the author of this article--rehydration rate (mL/h)=body weight (kg) × 10 (mL·kg-1·h-1) to calculate the rehydration rate within 8 h post injury (hereinafter referred to as the rehydration rate). The range of the results of the 3 accepted pediatric rehydration formulae ±20% were regarded as the reasonable rehydration rate, and the accuracy rates of rehydration rate calculated using the two pediatric emergency rehydration formulae were compared. Using the maximum burn areas (55% and 85% TBSA) corresponding to the reasonable rehydration rate calculated by the pediatric ten-fold rehydration formula at the body weight of 6 and 50 kg respectively, the total burn area of 30% to 100% TBSA was divided into 3 segments and the accuracy rates of the rehydration rate calculated using the 2 pediatric emergency rehydration formulae in each segment were compared. When neither of the rehydration rates calculated by the 2 pediatric emergency rehydration formulae was reasonable, the differences between the two rehydration rates were compared. The distribution of 433 pediatric patients in the 3 previous total burn area segments was counted and the accuracy rates of the rehydration rate calculated using the 2 pediatric emergency rehydration formulae were calculated and compared. Data were statistically analyzed with McNemar test. Results: Substitution of 6 319 pairs of simulated data showed that the accuracy rates of the rehydration rates calculated by the pediatric ten-fold rehydration formula was 73.92% (4 671/6 319), which was significantly higher than 4.02% (254/6 319) of the TWGB formula (χ2=6 490.88,P<0.05). When the total burn area was 30%-55% and 56%-85% TBSA, the accuracy rates of the rehydration rates calculated by the pediatric ten-fold rehydration formula were 100% (2 314/2 314) and 88.28% (2 357/2 670), respectively, which were significantly higher than 10.98% (254/2 314) and 0 (0/2 670) of the TWGB formula (with χ2 values of 3 712.49 and 4 227.97, respectively, P<0.05); when the total burn area was 86%-100% TBSA, the accuracy rates of the rehydration rates calculated by the pediatric ten-fold rehydration formula and the TWGB formula were 0 (0/1 335). When the rehydration rates calculated by the 2 pediatric emergency rehydration formulae were unreasonable, the rehydration rates calculated by the pediatric ten-fold rehydration formula were all higher than those of the TWGB formula. There were 93.07% (403/433), 5.77% (25/433), and 1.15% (5/433) patients in the 433 pediatric patients had total burn area of 30%-55%, 56%-85%, and 86%-100% TBSA, respectively, and the accuracy rate of the rehydration rate calculated using the pediatric ten-fold rehydration formula was 97.69% (423/433), which was significantly higher than 0 (0/433) of the TWGB formula (χ2=826.90, P<0.05). Conclusions: The application of the pediatric ten-fold rehydration formula to estimate the rehydration rate of pediatric patients after extensive burns is more accurate and convenient, superior to the TWGB formula, suitable for application by front-line healthcare workers that are not specialized in burns in pre-admission rescue of pediatric patients with extensive burns, and is worthy of promotion.
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Masculino , Femenino , Humanos , Niño , Quemaduras/terapia , Hospitalización , Resucitación , Fluidoterapia/métodos , Superficie Corporal , Estudios RetrospectivosRESUMEN
Bone marrow microenvironment is a highly complex environment surrounding tumor, which plays an important role in the survival, proliferation, drug resistance and migration of multiple myeloma (MM) cells. As an important cellular component in tumor microenvironment, tumor-associated macrophages(TAM) has attracted attention due to its key role in tumor progression and drug resistance. Targeting TAM has shown potential therapeutic value in cancer treatment. In order to clarify the role of macrophages in MM progression, it is necessary to understand the differentiation of TAM and its characteristics of promoting MM. This paper reviews the research progress on how TAM is programmed in MM and the mechanism of TAM promoting tumor development and drug resistance.
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Humanos , Mieloma Múltiple/patología , Macrófagos Asociados a Tumores , Macrófagos/patología , Diferenciación Celular , Microambiente TumoralRESUMEN
OBJECTIVE: The aim of this study was to establish a nomogram for predicting radiation-induced hypothyroidism (RHT) based on an equivalent dose at 2 Gy per fraction (EQD2) in patients with nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiation therapy (IMRT) with or without chemotherapy. METHODS: Two hundred forty-four eligible patients with NPC were recruited for this study. Patients' clinical factors and dose-volume parameters of the thyroid gland were retrieved from medical records and the IMRT treatment planning system, respectively. The irradiation doses were converted into EQD2 for analysis. Least absolute shrinkage and selection operator (LASSO) regression analysis and multivariate logistic regression analysis were performed to identify optimal predictors of RHT for constructing the nomogram. RESULTS: With a median follow-up of 63.0 months, the cumulative incidence rates of RHT at 3 months and 1-, 2-, 3-, 4- and 5- year after IMRT were 10.2%, 36.2%, 47.6%, 54.2%, 58.8% and 69.4%, respectively. Four independent factors for predicting RHT, including gender, age, pretreatment volume of the thyroid gland and V35Gy(3Gy) of the thyroid gland, were identified and incorporated into the nomogram. The area under the ROC curve of the nomogram was 0.747 (95% confidence interval 0.685 - 0.809). Calibration curves and DCA curves showed that the nomogram was in good agreement with the actual observations and clinical usefulness. CONCLUSIONS: The nomogram proposed in this study provides a reliable estimate of RHT risk in patients with NPC after IMRT and appears to have the potential to be a useful tool for widespread clinical applications.
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Hipotiroidismo , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Radioterapia de Intensidad Modulada , Humanos , Hipotiroidismo/etiología , Carcinoma Nasofaríngeo/tratamiento farmacológico , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/radioterapia , Nomogramas , Dosificación Radioterapéutica , Radioterapia de Intensidad Modulada/efectos adversos , Estudios RetrospectivosAsunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Biomarcadores de Tumor/genética , Carcinoma de Células Renales/diagnóstico , Carcinoma de Células Renales/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Renales/diagnóstico , Cinesinas/genética , PronósticoRESUMEN
Objective:To investigate the effects of recombinant adenovirus with human vascular endothelial growth factor 165 (Ad-hVEGF 165) and recombinant adenovirus with human tissue inhibitor of metalloproteinase 1 (Ad-hTIMP-1) on rats with myocardial infarction (MI) and its mechanism. Methods:A total of 30 healthy 8-week-old male Wistar rats were randomly divided into 5 groups: sham-operated group (sham), virus control group (Ad-Track), Ad-hVEGF 165 group, Ad-hTIMP-1 group and Ad-hVEGF 165+Ad-hTIMP-1 group (hVEGF 165+hTIMP-1) ( n=6 per group). Except the sham group, all rats were ligated the left anterior descending coronary artery to induce MI model with ST-segment elevation and Q waves or T-wave inversion on electrocardiogram and local myocardial whitening. The corresponding recombinant adenovirus comprising 100 μL (1×10 10 VP/100 μL) combined with NaCl solution was injected into the myocardial infarction area at four points respectively. The sham group received no treatment. After 4 weeks, all rats were sacrificed after echocardiography was completed and heart tissues were collected. The expression of hVEGF 165 and hTIMP-1 were detected by immunohistochemistry. The mRNA expression of apoptosis-related factors were detected by real-time PCR. The protein expression of apoptosis-related factors were detected by immunohistochemistry. Differences between groups were determined by One-way analysis of variance. Multiple comparisons between groups were performed using the least significant difference t-test. Results:(1) Both heart rate (HR) (480.83±24.09) beats/min, left ventricular end-diastolic dimension (LVEDD) (6.88±0.44) mm and left ventricular end-systolic dimension (LVESD) (4.85±0.42) mm were increased in the Ad-Track group than those in the sham group (433.16±17.86) beats/min, (6.20±0.45) mm, (4.06±0.70) mm (all P<0.05), and left ventricular ejection fraction (LVEF) (62.70±3.17) % and left ventricular fractional shortening (LVFS) (29.52±1.88) % were significantly decreased in the Ad-Track group than those in the sham group (72.78±5.44)%, (29.52±1.88) % (both P<0.01). Compared with the Ad-Track group, LVEF (71.50±6.23) % and LVFS (36.17±5.27) % in the hVEGF 165-hTIMP-1 group were significantly increased (both P<0.01), and LVEDD (6.22±0.39) mm and LVESD (4.13±0.23) mm were decreased (both P<0.05). LVEF and LVFS in the hVEGF 165-hTIMP-1 group were increased significantly than those in the Ad-hVEGF 165 group (64.65±4.00) %, (30.95±2.57) % (both P<0.05). The mRNA expression of BCL2-associated X protein (Bax), cysteine aspartate specific proteinase 3 (Caspase-3) and BCL-xL/BCL-2-associated death promoter (Bad) in the hVEGF 165-hTIMP-1 group were decreased than those in the Ad-Track group ( P<0.01 or P<0.05), and B-cell lymphoma/leukemia-2 (Bcl-2) in the hVEGF 165-hTIMP-1 group were increased than those in the Ad-Track group ( P<0.01). The mRNA expression levels of Bax and Caspase-3 in the hVEGF 165-hTIMP-1 group were decreased than those in the Ad-hVEGF 165 group (both P<0.05). There was no statistically difference in the mRNA expression of Bax, Caspase-3, Bad, and Bcl-2 between the hVEGF 165-hTIMP-1 group and the sham group (all P>0.05). The protein expression of Bax and Caspase-3 in the hVEGF 165-hTIMP-1 group were significantly decreased than those in the Ad-hVEGF 165 group, the Ad-hTIMP-1 group and the Ad-Track group (all P<0.01), and the protein expression of Bcl-2 in the hVEGF 165-hTIMP-1 group was increased than those in the Ad-hVEGF 165 group, the Ad-hTIMP-1 group and the Ad-Track group (all P<0.05). There were no statistically differences in the protein expression of Bax, Caspase-3 and Bcl-2 between the hVEGF 165-hTIMP-1 group and the sham group (all P>0.05). Conclusions:Ad-hVEGF 165 and Ad-hTIMP-1 can improve cardiac contractile function of MI rats and the beneficial effects are largely attributable to inhibiting myocyte apoptosis. The combination of hVEGF 165 and hTIMP-1 may have a synergistic effect on MI.
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Gut injury continues to be the devastating and unpredictable critical illness associated with increased cell death of intestinal epithelial cells (IECs). The IECs, immune system and microbiome are the interrelated entities to maintain normal intestinal homeostasis and barrier integrity. In response to microbial invasion, IEC cell death occurs to maintain intestinal epithelium function and retain the continuous renewal and tissue homeostasis. But the imbalance of IEC cell death results in increased intestinal permeability and barrier dysfunction that leads to several acute and chronic intestinal diseases, such as intestinal ischemia/reperfusion (I/R), sepsis, inflammatory bowel diseases (IBD), necrotizing enterocolitis (NEC), etc. During the pathophysiological state, the excessive IEC apoptotic cell death leads to a chronic inflammatory condition, later switches to necroptotic cell death mechanism that induces more pathological features than apoptosis and may also induce other lytic cell death mechanisms like pyroptosis and ferroptosis to increase the pathogenesis of the intestinal diseases. But still, there remains gaps in the fundamental knowledge about the IEC cell death mechanisms in chronic intestinal diseases. Together, a deep understanding of the specific cell death mechanisms underlying chronic intestinal diseases, including sepsis, IBD, NEC, and intestinal I/R, is desperately needed to develop emerging novel promising therapeutic strategies. This review aims to show how the acute and critical illness in the gut are driven by IEC cell death mechanism, such as apoptosis, necrosis, necroptosis, pyroptosis, and ferroptosis.
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Humanos , Recién Nacido , Apoptosis , Muerte Celular , Células Epiteliales , Mucosa Intestinal , NecrosisRESUMEN
OBJECTIVE@#To investigate the proliferation inhibition and pro-apoptosis effect of LY294002 (PI3K/AKT inhibtor) combined with daunorubicin (DNR) on the chronic myeloid leurenia cell line K562 and its possible mechanisms.@*METHODS@#The effect of LY294002 and DNR on the proliferation of K562 cells in different treating time and concentration were measured by MTT assay. The cell cycle was determined by flow cytometry, the mRNA and protein expression of SKP2 , P27, BCL-2 and BAX were determined by RT-PCR and Western blot.@*RESULTS@#LY294002 and DNR were able to inhibit the growth of K562 cells and promote apoptosis in time- and concentration-dependent manner (P<0.05), both the cell proliferation-inhibiting rate and apoptosis rate in combination therapy group were higher than that in DNR-monotherapy group (P<0.05). After K562 cells treated by LY294002 combined DNR for 36 h, the cells were statistically significantly reduced in G/M phase (P<0.05), as compared with control group and DNR group. Compared with DNR group, the cell level of G/G phase rased (P<0.05) and cell level of S phase decreased (P>0.05). Compared with DNR group, the expresson of SKP2 and BCL-2 mRNA decreased, and the expression of P27 mRNA increased in the combination therapy group (P<0.05). The expression of BAX mRNA was not significantly different between different groups. The same result was found in the protein expression.@*CONCLUSION@#LY294002 has the sensibilizative effect on DNR chemotherapy, which may be relative with blocking the cell cycle and inducing cell apoptosis.
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OBJECTIVE@#To investigate the mutation rate and distribution of Homo sapiens neuroblastoma RAS viral oncogene homolog (NRAS) gene in the patients with acute myeloid leukemia.@*METHODS@#The genomic DNA of bone marrow was screened by polymerase chain reaction (PCR) and sequencing for NRAS mutations. At the same time, the mutations of ASXL1, DNMT3A, TET2, CEBPA, FLT3, IDH2, NPM1 and c-KIT genes were also detected to analyze the relation with NRAS mutations.@*RESULTS@#A total of 11 NRAS mutations were found in 108 patients with initial acute myeloid leukemia and the mutation rate was 10.2%, including 6 cases of G12D, 3 cases of G13D, and 2 cases of G61K. In the mutation group, the peripheral blood leukocyte count was higher (P<0.05), more likely to occur in the M subtype, and the M subtype was mutually exclusive (P<0.05). Moreover, the mutant group was more likely to express CD13 than the non-mutation group (P<0.05), while no statistic difference was found in age, gender, hemoglobin level, platelet count, lactate dehydrogenase level, bone marrow blast, cytogenetics, complete remission rate and overall survival (P>0.05).@*CONCLUSIONS@#The mutation of NRAS gene has no effect on the prognosis of AML patients.
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Objective: To investigate the expression level and clinical significance of a long non-coding RNA (LncRNA), BC200 in non-small cell lung cancer (NSCLC) and analyze its correlation with the epithelial-mesenchymal transition (EMT)-related proteins, E-cad-herin, N-cadherin, and Snail. Methods: Sixty NSCLC and sixty paired adjacent tissue samples were collected to detect the BC200 levels. Furthermore, 40 samples of NSCLC and 40 samples of normal lung tissues were collected to quantify the messenger RNA (mRNA) lev-els of E-cadherin, N-cadherin, and Snail using quantitative polymerase chain reaction. The relationship between the BC200 level and mRNA levels of E-cadherin, N-cadherin, and Snail was explored in NSCLC tissues. The correlation between BC200 and clinical pathologi-cal parameters (gender, age, TNM stage, tumor size, lymph node metastasis, and pathologic type) was also analyzed. Receiver operat-ing characteristic curve (ROC) was constructed to evaluate the diagnostic efficiency of BC200. Immunohistochemical staining was per-formed to determine the expression levels of E-cadherin, N-cadherin, and Snail in 40 specimens of NSCLC and 20 specimens of normal lung tissue and their correlation to the expression levels of BC200 was evaluated. Results: 1) The expression of BC200, N-cadherin mRNA, and Snail mRNA was significantly upregulated in the tumor tissues when compared to that in normal lung tissues (P<0.05). The expression of E-cadherin mRNA was significantly lower in tumor tissues than in the normal lung tissues (P<0.05). 2) The positive rate of E-cadherin, N-cadherin, and Snail in NSCLC was 40% (16/40) , 57.5% (23/40), and 57.5% (23/40), respectively, while that of normal lung tissues was 95% (19/20), 5% (1/20), and 10% (2/20), respectively. There was a significant difference between these two data sets (P<0.05). 3) BC200 is highly expressed in the NSCLC tissues. The high expression of BC200 in lung cancer was correlated with lymph node metastasis, clinical stage, and positive rate of E-cadherin, N-cadherin, and Snail. The expression of BC200 in NSCLC tissues was negatively correlated with the expression of E-cadherin mRNA (r=-0.31, P<0.05) and positively correlated with the expression of Snail and N-cadherin mRNA (r=0.305, r=0.257, P<0.05). 4) ROC analysis of BC200 indicated a potential diagnostic value of BC200 levels in NSCLC . Conclusions: BC200 is highly expressed in NSCLC tissues, which was correlated with lymph node metastasis, clinical stage, E-cadherin, N-cadherin, and Snail positive rate. The expression of BC200 in NSCLC tissues was negatively correlated with E-cadherin and positively correlated with Snail and N-cadherin. BC200 may regulate the invasion and migration ability of NSCLC by EMT. BC200 may be a potential tumor marker for NSCLC diagnosis.
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Biobased unsaturated polyester thermosets as potential replacements for petroleum-based thermosets were designed. The target of incorporating rigid units, to yield thermosets with high thermal and mechanical performance, both in the biobased unsaturated polyester (UP) and reactive diluent (RD) while retaining miscibility was successfully achieved. The biobased unsaturated polyester thermosets were prepared by varying the content of isosorbide, 1,4-butanediol, maleic anhydride, and succinic anhydride in combination with the reactive diluent isosorbide-methacrylate (IM). Isosorbide was chosen as the main component in both the UP and the RD to enhance the rigidity of the formed thermosets, to overcome solubility issues commonly associated with biobased UPs and RDs and volatility and toxicity associated with styrene as RD. All UPs had good solubility in the RD and the viscosity of the mixtures was primarily tuned by the feed ratio of isosorbide but also by the amount of maleic anhydride. The flexural modulus and storage modulus were tailorable by altering the monomer composition The fabricated thermosets had superior thermal and mechanical properties compared to most biobased UP thermosets with thermal stability up to about 250 °C and a storage modulus at 25 °C varying between 0.5 and 3.0 GPa. These values are close to commercial petroleum-based UP thermosets. The designed tailorable biobased thermosets are, thus, promising candidates to replace their petroleum analogs.
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Fuentes Generadoras de Energía , Isosorbida/química , Poliésteres/síntesis química , Butileno Glicoles/química , Anhídridos Maleicos/química , Metacrilatos/química , Poliésteres/toxicidad , Solubilidad , Anhídridos Succínicos/química , VolatilizaciónRESUMEN
A pathway to biobased polyamides (PAs) via ring-opening aminolysis-condensation (ROAC) under benign conditions with diverse structure was designed. Ethylene brassylate (EB), a plant oil-derived cyclic dilactone, was used in combination with an array of diamines of diverse chemical structure, and ring-opening of the cyclic dilactone EB was revealed as a driving force for the reaction. The ROAC reactions were adjusted, and reaction conditions of 100 °C under atmospheric pressure using 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) as a catalyst for 24 h were optimal. The structures of the polyamides were confirmed by mass spectroscopy, FTIR, and NMR, and the PAs had viscosity average molecular weights ( Mη) of â¼5-8 kDa. Glassy or semicrystalline PAs with glass transition temperatures between 48 and 55 °C, melting temperatures of 120-200 °C for the semicrystalline PAs, and thermal stabilities above 400 °C were obtained and were comparable to the existing PAs with similar structures. As a proof-of-concept of their usage, one of the PAs was shown to form fibers by electrospinning and films by melt pressing. Compared to conventional methods for PA synthesis, the ROAC route portrayed a reaction temperature at least 60-80 °C lower, could be readily carried out without a low-pressure environment, and eliminated the use of solvents and toxic chemicals. Together with the plant oil-derived monomer (EB), the ROAC route provided a sustainable alternative to design biobased PAs.
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Éteres Cíclicos/química , Nylons/síntesis química , Técnicas de Química Sintética/métodos , PolimerizacionRESUMEN
The current work explores the sodium hydride mediated polycondensation of aliphatic diols with diethyl carbonate to produce both aliphatic polycarbonates and cyclic carbonate monomers. The lengths of the diol dictate the outcome of the reaction; for ethylene glycol and seven other 1,3-diols with a wide array of substitution patterns, the corresponding 5-membered and 6-membered cyclic carbonates were synthesized in excellent yield (70-90%) on a 100 gram scale. Diols with longer alkyl chains, under the same conditions, yielded polycarbonates with an M w ranging from 5000 to 16 000. In all cases, the macromolecular architecture revealed that the formed polymer consisted purely of carbonate linkages, without decarboxylation as a side reaction. The synthetic design is completely solvent-free without any additional post purification steps and without the necessity of reactive ring-closing reagents. The results presented within provide a green and scalable approach to synthesize both cyclic carbonate monomers and polycarbonates with possible applications within the entire field of polymer technology.
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Objective: To explore the diagnostic dosage of enhanced computed tomography (CT) of chest and its influence factor through analyzed the data of radiation dosage of enhanced CT of chest. Methods: The scanning data of 297 patients who were implemented scan on 4 different CT devices were compared by using retrospective analysis. And they were divided into A, B, C and D group as different device. The differences of scan sequence among different devices were compared, and volume computed tomography dose index(CTDIvol), dose length product(DLP) and effective dose(ED) were recorded and analyzed. Results: The CTDIvols of 4 groups were (12.18±4.13), (8.86±3.18), (10.70±5.18) and 13.59mGy, respectively, and the differences among them were significant (F=38.58, P<0.05). And the DLPs of the 4 groups were (433.54±145.18), (311.62±112.75), (368.04±181.22) and (475.75±34.25)mGy·cm, and the differences among these groups were significant (F=36.33, P<0.05). Besides, the EDs of the 4 groups were (6.07±2.03), (4.36±1.58), (5.15±2.54) and (6.66±0.48) mSv, and the differences among these groups also were significant (F=36.32, P<0.05). And the comparison between any two means of radiation dosage were significant. Conclusion: The exposure dose of patients who received enhanced CT of chest was correlative with the type of CT device and acquisition parameters. And the effective dosage of patients under automatic tube current module was lower than that of fixed tube current module. And the modulation technique of current of ray tube as angle can efficiently reduce the effective dose. In clinical practice, patients' radiation dosage can be reduced by optimizing the scanning parameters.
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An increased sustainabile awarness has inspired the development of new polymeric networks in a remarkable way and this strive should be combined with environmentally concerned end-uses. Therefore, a UV-crosslinked polyhydroxyurethane film with antibacterial properties is developed. First, a hydroxyurethane precursor is synthesized using aminolysis condensation, circumventing the use of isocyanates. The films are subsequently crosslinked under solvent-free conditions through a UV-triggered thiol-ene mechanism. The reactions are monitored by 1 H nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, and Raman spectroscopy, and the networks have gel contents above 90%, and are transparent, hydrophilic, and highly flexible. Antibacterial properties are achieved by a controlled quaternization of the network's tertiary-amine and methylation of thiol-ether functionality, resulting in quaternary ammonium compounds (QACs) and sulfonium compounds. The antibacterial properties are evaluated against both Escherichia coli and Staphylococcus aureus using the agar plate diffusion and tube shaking methods. The QAC-loaded films exhibit outstanding bactericide properties (>99.9%) and the antibacterial mechanism is demonstrated to be a dual killing mechanism, i.e., diffusion killing and contact active killing.
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Antibacterianos/farmacología , Reactivos de Enlaces Cruzados/química , Geles/química , Isocianatos/química , Poliuretanos/química , Rayos Ultravioleta , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Espectroscopía de Protones por Resonancia Magnética , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus/efectos de los fármacos , TermogravimetríaRESUMEN
Objective To investigate the effects of continuous theta burst stimulation (cTBS) on the motor network in the motor area,in order to provide a new way for the basic treatment of motor function.Methods A total of 12 healthy subjects were recruited to stimulate the primary motor areas of the brain by continuous theta burst transcranialmagnetic stimulation,and finger movements were tested before and after stimulation,while the EEG was collected.Pearson correlation method was used to analyze the related characteristics of EEG signals,construct and analyze the functional network of brain,and study the characteristic parameters of brain function network.Results The correlation coefficient matrix,the topological map of the functional network and the parameters of the functional network of the brain were not changed before and after the intervention in the pseudo stimulus group (all P>0.05);Before stimulation,as compared with after stimulation,cTBS stimulated the motor area,the key button exercise test mean reaction time increased,the degree of network node decreased,the cluster coefficient increased,the network of "small world" property reduced.After cTBS stimulation,there were significant differences (P<0.05).Conclusion The cTBS mode of transcranial magnetic stimulation (TMS) can change the topological structure and network parameters of brain function network,and improve the motor function.
RESUMEN
Objective:To investigate the expression and clinical significance of glioma cancer-related gene homologous protein 1 (Gli-1) and epithelial-mesenchymal transition (EMT)-related proteins, namely, Snail, E-cadherin, and N-cadherin in non-small cell lung cancer (NSCLC). Methods:Immunohistochemical staining was performed to determine the expression levels of Gli-1, Snail, E-cadherin, and N-cadherin in 67 cases of NSCLC and 20 cases of normal lung tissues and its relationship with clinicopathological features and prognosis was explored. Another 20 samples of fresh NSCLC tissues and corresponding normal lung tissues were collected to detect the mRNA level through reverse transcription polymerase chain reaction (RT-PCR). Results:1) The positive rates of Gli-1, Snail, E-cadherin, and N-cadherin in NSCLC were 61.19%(41/67), 50.75%(34/67), 56.72%(38/67), and 53.73%(36/67), respectively;whereas those of normal lung tissues were 20%(4/20), 10%(2/20), 100%(20/20), and 5%(1/20), respectively. These two sets of data have significant statistical difference (P<0.05). 2) The high expression of Gli-1 in tumor tissues was closely related to lymph node metastasis, tumor, node, and metastasis (TNM) stage, and tumor differentiation (P<0.05) but was not associated with gender, age, tumor size, and pathological type. The expression of Gli-1 in NSCLC tissues was negatively correlated with E-cadherin (r=-0.325, P<0.05) and positively correlated with Snail and N-cadherin (r=0.379, r=0.490, P<0.05). 3) RT-PCR results showed that the expression levels of Gli-1, Snail, and N-cad-herin mRNA were significantly higher in NSCLC cases than in normal lung cases (P<0.05). The expression level of E-cadherin mRNA was lower in tumor tissues than in lung tissues (P<0.05). 4) Patients with high expression levels of Gli-1, Snail, and N-cadherin had signifi-cantly worse prognosis and lower survival rate than those with low expression (all P<0.05), whereas patients with low expression lev-els of E-cadherin had significantly better prognosis and lower survival rate than those with high expression (P<0.05). Multivariate Cox's proportional hazard regression analysis indicated that E-cadherin-negative group expression, lymph node metastasis, TNM stage, and tumor differentiation were independent prognostic factors for NSCLC. Conclusion: The abnormal activation of Hedgehog signaling pathway in NSCLC is correlated with EMT. Detecting the expression levels of Gli-1 and EMT-related proteins Snail, E-cadherin, and N-cadherin might be helpful in understanding the clinicopathological features and prognosis of patients with NSCLC.