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1.
Food Chem ; 453: 139560, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38761721

RESUMO

Baijiu authenticity has been a frequent problem driven by economic interests in recent years, so it is important to discriminate against baijiu with different origins. Herein, we proposed a simple and efficient esters-targeted colorimetric sensor array mediated by hydroxylamine hydrochloride. Esters undergo a nucleophilic addition reaction with hydroxylamine hydrochloride to form hydroxamic acid, which rapidly forms a purplish red ferric hydroxamate under FeCl3·6H2O. Bromophenol blue and rhodamine B enrich the color effects. The array detected 12 esters with a detection limit on the order of 10-5 of most esters and 16 mixed esters with R2 > 0.999 and recoveries close to 100%. Otherwise, for discriminating 34 strong-aroma baijius (SABs), the array has an accuracy of 98% according to the origin, and 95% according to the grades, with a response time of 1 min. This study provides a new strategy for authenticity determination and quality control of baijiu.

2.
Food Chem ; 447: 138968, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38489877

RESUMO

Given the severe problem of Baijiu authenticity, it is essential to discriminate Baijiu from different origins quickly and effectively. As organic acids (OAs) are the most dominant taste-imparting substances in Baijiu, we proposed a simple, fast, and effective OAs-targeted colorimetric sensor array based on the colorimetric reaction of 4-aminophenol (AP)/4-amino-3-chlorophenol (ACP) under oxidation of Cu(NO3)2 for the rapid discrimination of origins of Baijiu with three main aroma types. Hydrogen ions ionized from OAs induced the protonation of the amino group, which blocked the colorimetric reaction, and the different levels of OAs in Baijiu enabled the array to discriminate different origins of Baijiu. The array was implemented to analyze 10 simple OAs and 16 mixed OAs and further for the discrimination of 42 Baijius with an accuracy of 98%. This method provided an efficient research strategy for a basis for rapid quality analysis of Baijiu.


Assuntos
Clorofenóis , Odorantes , Compostos Orgânicos Voláteis , Odorantes/análise , Colorimetria , Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos Orgânicos Voláteis/análise , Ácidos/análise
3.
Singapore Med J ; 64(12): 728-731, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34628800

RESUMO

Introduction: Post-anaesthesia care unit (PACU) delirium affects 5%-45% of patients after surgery and is associated with postoperative delirium and increased mortality. Up to 40% of PACU delirium is preventable, but it remains under-recognised due to a lack of awareness of its diagnosis. The nursing delirium screening scale (Nu-DESC) has been validated for diagnosing PACU delirium, but is not routinely used locally. This study aimed to use Nu-DESC to establish the incidence and risk factors of PACU delirium in patients undergoing non-cardiac surgery in the surgical population. Methods: We conducted an audit of eligible patients undergoing major surgery in three public hospitals in Singapore over 1 week. Patients were assessed for delirium 30-60 min following their arrival in PACU using Nu-DESC, with a total score of ≥2 indicative of delirium. Results: A total of 478 patients were assessed. The overall incidence rate of PACU delirium was 18/478 (3.8%), and the incidence was 9/146 (6.2%) in patients aged > 65 years. Post-anaesthesia care unit delirium was more common in females, patients with malignancy and those who underwent longer operations. Logistic regression analysis showed that the use of bispectral index (P < 0.001) and the presence of malignancy (P < 0.001) were significantly associated with a higher incidence of PACU delirium. Conclusion: In this first local study, the incidence of PACU delirium was 3.8%, increasing to 6.2% in those aged > 65 years. Understanding these risk factors will form the basis for which protocols can be established to optimise resource management and prevent long-term morbidities and mortality in PACU delirium.


Assuntos
Anestesia , Delírio , Neoplasias , Feminino , Humanos , Delírio/diagnóstico , Delírio/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Singapura/epidemiologia , Estudos Prospectivos , Anestesia/efeitos adversos , Fatores de Risco
4.
Anticancer Drugs ; 33(10): 989-998, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36206129

RESUMO

Oovarian cancer is a common lethal gynecological malignancy with a high occurrence and dismal prognosis on account of its drug resistance. MicroRNAs (miRNAs) are widely involved in the chemotherapy resistance of tumors, including miR-30a-5p. Herein, we probed the functional role and molecular mechanism of miR-30a-5p in the chemoresistance of ovarian cancer. We enrolled 48 ovarian cancer patients in this study. Statistical analysis and a series of experiments including quantitative reverse transcription polymerase chain reaction, western blot, methyl thiazolyl tetrazolium assay, colony formation assay, flow cytometry analysis, Transwell assay, luciferase reporter assay, RNA pull-down assay and TOP/FOP flash assay were explored in the study. Animal experiments were performed to verify the role of miR-30a-5p in vivo . In our study, miR-30a-5p showed a prominently low level in ovarian cancer tissues and cells. Importantly, its expression in cisplatin-resistant cell lines was more downregulated than in cisplatin-sensitive ones. Additionally, miR-30a-5p overexpression inhibited proliferative, migratory and invasive abilities of ovarian cancer cells while enhancing cell apoptosis and improving cell sensitivity to cisplatin in ovarian cancer. Further, miR-30a-5p targeted to chromodomain helicase DNA binding protein 1 (CHD1) and inhibited the expression of CHD1 in ovarian cancer. Moreover, rescue experiments manifested that miR-30a-5p weakened cisplatin resistance and the cellular process of ovarian cancer by mediating CHD1. Besides, miR-30a-5p regulated CHD1 expression to suppress Wnt/ß-catenin signaling in ovarian cancer. The findings were verified by in vivo experiments. This article elucidated that miR-30a-5p/CHD1 axis inhibited the cellular process and enhanced cisplatin sensitivity of ovarian cancer cells through the Wnt/ß-catenin pathway, which may provide a useful direction for the targeted chemotherapy of ovarian cancer.


Assuntos
DNA Helicases , Proteínas de Ligação a DNA , MicroRNAs , Neoplasias Ovarianas , Animais , Feminino , Humanos , beta Catenina/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Cisplatino/farmacologia , Cisplatino/uso terapêutico , DNA Helicases/genética , DNA Helicases/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica , Luciferases/genética , Luciferases/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Via de Sinalização Wnt
5.
Materials (Basel) ; 15(19)2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36234050

RESUMO

Fe additives may play an important role in the preparation of aluminum-based hydrolysis hydrogen powder, with high hydrogen yield, low cost, and good oxidation resistance. Therefore, it is necessary to ascertain the effect of Fe on the hydrogen production performance of Al-Bi-Sn composite powders. According to the calculated vertical cross-section of the Al-10Bi-7Sn-(0~6)Fe (wt.%) quasi-binary system, Al-10Bi-7Sn-xFe (x = 0, 0.5, 1.5, 3) wt.% composite powders for hydrogen production were prepared by the gas-atomization method. The results showed that the Al-10Bi-7Sn-1.5Fe (wt.%) powder exhibited an extremely fast hydrogen generation rate at 50 °C, which reached 1105 mL·g-1 in 27 min in distilled water, 1086 mL·g-1 in 15 min in 0.1 mol·L-1 NaCl solution, and 1086 mL·g-1 in 15 min in 0.1 mol·L-1 CaCl2 solution. In addition, the antioxidant properties of these powders were also investigated. The results showed that the hydrogen production performance of the Al-10Bi-7Sn-1.5Fe (wt.%) powder could retain 91% of its hydrogen production activity, even though the powder was exposed to 25 °C and 60 RH% for 72 h. The addition of Fe not only promoted the hydrogen generation rate of the Al-Bi-Sn composite powders, but also improved their oxidation resistance. The Al-10Bi-7Sn-1.5Fe (wt.%) composite powder shows great potential for mobile hydrogen source scenarios with rapid hydrogen production.

7.
Materials (Basel) ; 15(9)2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35591431

RESUMO

In this work, two isothermal sections of the Co-Ta-Si ternary system at 900 °C and 1100 °C are constructed in the whole composition range via phase equilibrium determination with the help of electron probe microanalysis (EPMA) and X-ray diffraction (XRD) techniques. Firstly, several reported ternary phases G (Co16Ta6Si7), G″ (Co4TaSi3), E (CoTaSi), L (Co3Ta2Si) and V (Co4Ta4Si7) are all re-confirmed again. The G″ phase is found to be a kind of high-temperature compound, which is unstable at less than 1100 °C. Additionally, the L phase with a large composition range (Co32-62Ta26-36Si10-30) crystallizes with a hexagonal crystal structure (space group: P63/mmc, C14), which is the same as that of the binary high-temperature λ1-Co2Ta phase. It can be reasonably speculated that the ternary L phase results from the stabilization toward low-temperature of the binary λ1-Co2Ta through adding Si. Secondly, the binary CoTa2 and SiTa2 phases are found to form a continuous solid solution phase (Co, Si)Ta2 with a body-centered tetragonal structure. Thirdly, the elemental Si shows a large solid solubility for Co-Ta binary compounds while the Ta and Co are hardly dissolved in Co-Si and Ta-Si binary phases, respectively.

8.
Anesth Analg ; 135(2): 376-384, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35245225

RESUMO

BACKGROUND: Emergency front-of-neck access (FONA) is particularly challenging with impalpable neck anatomy. We compared 2 techniques that are based on a vertical midline neck incision, followed by finger dissection and then either a cannula or scalpel puncture to the cricothyroid membrane. METHODS: A manikin simulation scenario of impalpable neck anatomy and bleeding was created. Sixty-five anesthesiologists undergoing cricothyrotomy training performed scalpel-finger-cannula (SFC) and scalpel-finger-bougie (SFB) cricothyrotomy in random order. Primary outcomes were time to oxygen delivery and first-attempt success; data were analyzed using multilevel mixed-effects models. RESULTS: SFC was associated with a shorter time to oxygen delivery on univariate (median time difference, -61.5 s; 95% confidence interval [CI], -84.7 to -38.3; P < .001) and multivariable (mean time difference, -62.1 s; 95% CI, -83.2 to -41.0; P < .001) analyses. Higher first-attempt success was reported with SFC than SFB (47 of 65 [72.3%] vs 18 of 65 [27.7%]). Participants also had higher odds at achieving first-attempt success with SFC than SFB (odds ratio [OR], 10.7; 95% CI, 3.3-35.0; P < .001). Successful delivery of oxygen after the "can't intubate, can't oxygenate" (CICO) declaration within 3 attempts and 180 seconds was higher (84.6% vs 63.1%) and more likely with SFC (OR, 5.59; 95% CI, 1.7-18.9; P = .006). Analyzing successful cases only, SFC achieved a shorter time to oxygen delivery (mean time difference, -24.9 s; 95% CI, -37.8 to -12.0; P < .001), but a longer time to cuffed tube insertion (mean time difference, +56.0 s; 95% CI, 39.0-73.0; P < .001). After simulation training, most participants preferred SFC in patients with impalpable neck anatomy (75.3% vs 24.6%). CONCLUSIONS: In a manikin simulation of impalpable neck anatomy and bleeding, the SFC approach demonstrated superior performance in oxygen delivery and was also the preferred technique of the majority of study participants. Our study findings support the use of a cannula-based FONA technique for achieving oxygenation in a CICO situation, with the prerequisite that appropriate training and equipment are available.


Assuntos
Manuseio das Vias Aéreas , Cânula , Manuseio das Vias Aéreas/métodos , Cartilagem Cricoide/cirurgia , Estudos Cross-Over , Humanos , Intubação Intratraqueal , Manequins , Oxigênio
9.
Ann Acad Med Singap ; 51(2): 87-95, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35224604

RESUMO

INTRODUCTION: Post-anaesthesia care unit (PACU) delirium is a potentially preventable condition that results in a significant long-term effect. In a multicentre prospective cohort study, we investigate the incidence and risk factors of postoperative delirium in elderly patients undergoing major non-cardiac surgery. METHODS: Patients were consented and recruited from 4 major hospitals in Singapore. Research ethics approval was obtained. Patients older than 65 years undergoing non-cardiac surgery >2 hours were recruited. Baseline perioperative data were collected. Preoperative baseline cognition was obtained. Patients were assessed in the post-anaesthesia care unit for delirium 30-60 minutes after arrival using the Nursing Delirium Screening Scale (Nu-DESC). RESULTS: Ninety-eight patients completed the study. Eleven patients (11.2%) had postoperative delirium. Patients who had PACU delirium were older (74.6±3.2 versus 70.6±4.4 years, P=0.005). Univariate analysis showed those who had PACU delirium are more likely to be ASA 3 (63.6% vs 31.0%, P=0.019), had estimated glomerular filtration rate (eGFR) of >60mL/min/1.73m2 (36.4% vs 10.6%, P=0.013), higher HbA1C value (7.8±1.2 vs 6.6±0.9, P=0.011), raised random blood glucose (10.0±5.0mmol/L vs 6.5±2.4mmol/L, P=0.0066), and moderate-severe depression (18.2% vs 1.1%, P=0.033). They are more likely to stay longer in hospital (median 8 days [range 4-18] vs 4 days [range 2-8], P=0.049). Raised random blood glucose is independently associated with increased PACU delirium on multivariate analysis.


Assuntos
Anestesia , Delírio , Idoso , Período de Recuperação da Anestesia , Delírio/diagnóstico , Delírio/epidemiologia , Delírio/etiologia , Humanos , Incidência , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Fatores de Risco
10.
J Clin Monit Comput ; 36(4): 1139-1145, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34347225

RESUMO

We compared the hyperangulated McGrath X-blade with the Macintosh-type CMAC videolaryngoscope through the use of manual in-line stabilization on patients. The primary hypothesis was that the McGrath X-blade has a similar first-attempt success rate as the CMAC videolaryngoscope. 210 patients of ASA physical status I to III, aged 21 to 80 years old, undergoing general anesthesia requiring tracheal intubation were prospectively recruited into this two-centre randomized controlled trial, from June 2016 to April 2019. Patients with history of or predicted difficult airway, pre-existing dental risks, BMI > 35 kg/m2, cervical spondylosis or myelopathy, aspiration risks, patients who declined to participate or lacked the mental capacity to give consent were excluded. Participants were intubated using either hyperangulated McGrath X-blade (MGX) or Macintosh-type CMAC (CM) videolaryngoscopy, with manual in-line stabilization. Primary outcome measured was first-attempt tracheal intubation success. Secondary outcomes included overall successful intubation within 2 attempts or 120 s, time to intubation, glottic view obtained and intubation-related complications. First-attempt success rates were 71.4% in the MGX group vs. 79.0% in the CM group (p = 0.26), with an absolute difference of -7.6% (95%CI -20%, 5.0%, p value = 0.26), but this trial was underpowered to detect a difference. Overall success was 91.4% (MGX) vs. 92.4% (CM) (p > 0.99). The Cormack & Lehane laryngeal grade was superior in the MGX group compared to CM group (Grade I: MGX 44%, CM 23%; Grade II: MGX 53%, CM 45%; Grade III: MGX 3%, CM 32%; p < 0.001). The median time to intubation using the MGX was longer than the CM [MGX 55.5 s (42.1-78.3), CM 43.8 s (38-55.3); p < 0.001]. Our study did not demonstrate a significant difference in efficacy between the McGrath X-blade and the CMAC videolaryngoscope. In patients with manual in-line stabilization, no anticipated airway difficulty and in the hands of experienced operators, the McGrath X-blade provided superior glottic views but conferred no advantage over the C-MAC, with a longer median time to intubation compared to the CMAC videolaryngoscope.Trial registration: Australian New Zealand Clinical Trial Registry (ACTRN12616000668404).


Assuntos
Laringoscópios , Laringoscopia , Adulto , Idoso , Idoso de 80 Anos ou mais , Austrália , Glote , Humanos , Intubação Intratraqueal , Pessoa de Meia-Idade , Gravação em Vídeo , Adulto Jovem
11.
Anaesth Intensive Care ; 49(5): 395-403, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34550812

RESUMO

The Ambu® AuraGain™ (Ambu A/S, Ballerup, Denmark) is a newer phthalate-free, single-use supraglottic device with the advantage of a facility for tracheal intubation if necessary intraoperatively. We compared the oropharyngeal leak pressures and other performance variables between the AMBU AuraGain and the LMA® Supreme™ (Teleflex Medical, Athlone, Co. Westmeath, Ireland) in patients undergoing laparoscopic cholecystectomy and preperitoneoscopic inguinal herniorrhaphy with carbon dioxide insufflation under controlled ventilation. We recruited 120 American Society of Anesthesiologists physical status class I-3 patients between the ages of 21 and 80 years undergoing laparoscopic cholecystectomy or preperitoneoscopic inguinal herniorrhaphy into this single-centre randomised controlled trial. The primary outcome measure was the oropharyngeal leak pressures. Secondary outcomes included insertion parameters, ventilatory characteristics and postoperative sequelae. The AuraGain had slightly but significantly higher oropharyngeal leak pressures than the LMA Supreme (mean (standard deviation) 26.1 (6.9) versus 21.4 (4.7) cmH2O, P < 0.010). The overall insertion success of the AuraGain was comparable to the LMA Supreme (AuraGain 58/60 (96.7%); LMA Supreme 56/59 (94.9%), P = 0.679). The AuraGain was deemed more difficult to insert than the LMA Supreme, with 26/60 (43.3%) of AuraGain insertions graded easy versus 48/59 (81.4%) of LMA Supreme, P < 0.001. The mean time to insertion of the AuraGain was slightly longer than the LMA Supreme, 32.2 (10.5) versus 28.3 (12.0) s, P < 0.001. Intraoperative device failure occurred following carbon dioxide insufflation in one AuraGain and three LMA Supremes, bringing the perioperative success rate of AuraGain and LMA Supreme to 95% and 89.8%, respectively, P = 0.322. No cases of regurgitation and aspiration occurred, and minor postoperative complications were similar. The AuraGain exhibited higher oropharyngeal leak pressures than the LMA Supreme, but was slightly more difficult to insert. The higher oropharyngeal leak pressures suggest that ventilation might be less affected by high peak inspiratory pressures when using the AuraGain than the LMA Supreme.


Assuntos
Laparoscopia , Máscaras Laríngeas , Adulto , Idoso , Idoso de 80 Anos ou mais , Manuseio das Vias Aéreas , Humanos , Intubação Intratraqueal , Máscaras Laríngeas/efeitos adversos , Pessoa de Meia-Idade , Pressão , Adulto Jovem
12.
A A Pract ; 15(4): e01436, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33783373

RESUMO

A patient with ankylosing spondylitis in a "can't intubate, can't oxygenate" situation was rescued with cannula cricothyrotomy and transtracheal jet oxygenation. The case revealed clinical and systematic weaknesses, leading to standardization and reorganization of our equipment. Prepackaged cannula cricothyrotomy sets were placed in standardized locations in the operating rooms in line with our institution's "cannula first" policy. Cognitive aids specific to emergency front-of-neck access (eFONA) were created and placed strategically with the eFONA equipment to prompt and guide operators during airway emergencies. The aids have also been incorporated into our training curriculum to encourage their use.


Assuntos
Emergências , Espondilite Anquilosante , Manuseio das Vias Aéreas , Cânula , Cognição , Humanos
15.
J Clin Monit Comput ; 35(3): 443-447, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32274646

RESUMO

General anaesthesia is sometimes favoured over regional anaesthesia in ophthalmic surgery. The use of supraglottic airway (SGA) or laryngeal mask airway (LMA) as the primary airway device is increasing due to numerous advantages over tracheal intubation. Compared with 1st generation SGAs, 2nd generation SGAs have an added benefit of isolating the airway from the alimentary tract. However, the vertical profile of SGAs may encroach into the surgical field and hence interfere with surgery. We investigated the vertical projections of 1st generation SGAs (LMA Classic, Ambu AuraFlex) and commonly used 2nd generation SGAs in our institution (LMA ProSeal, LMA Supreme, LMA Protector, Ambu AuraGain and I-gel) in a manikin model. Each device was connected to a corrugated catheter mount or angled connector following insertion as per usual clinical practice in our institutions. Vertical projections of all devices were measured from the chin using a centimetre ruler. Securing of airway device to the chin with an adhesive tape was possible for the LMA Classic and Ambu AuraFlex with straight corrugated connector, whereas the stiffer 2nd generations SGAs required the addition of an angled connector or straight corrugated tubing to direct the airway tube caudally, away from the surgical field. The LMA ProSeal had the lowest vertical projection amongst the 2nd generation SGAs and may be the suitable choice for ophthalmic surgery. We also describe a novel technique of utilising a 1st generation SGA with placement of an orogastric tube, although with some reservations. This study has several limitations and transferability of our findings into clinical practice is questionable as the use of a manikin may not fully imitate the real condition of the patient. Our study is the first study comparing vertical projected height of different SGAs in manikin, but future studies should investigate the use of SGA in the clinical setting during ophthalmic surgery.


Assuntos
Máscaras Laríngeas , Manequins , Anestesia Geral , Face , Humanos , Intubação Intratraqueal
16.
Ann Acad Med Singap ; 49(11): 876-884, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33381781

RESUMO

INTRODUCTION: Airway management outside the operating room can be challenging, with an increased risk of difficult intubation, failed intubation and complications. We aim to examine airway practices, incidence of difficult airway and complications associated with airway code (AC) activation. METHODS: We conducted a prospective audit of AC activations and adverse events in two tertiary hospitals in Singapore. We included all adult patients outside the operating room who underwent emergency intubation by the AC team after AC activation. Adult patients who underwent emergency intubation without AC activation or before the arrival of the AC team were excluded. Data were collected and documented by the attending anaesthetists in a standardised survey form shortly after their responsibilities were completed. RESULTS: The audit was conducted over a 20-month period from July 2016 to March 2018, during which a total of 224 airway activations occurred. Intubation was successful in 218 of 224 AC activations, giving a success rate of 97.3%. Overall, 48 patients (21.4%) suffered an adverse event. Thirteen patients (5.8%) had complications when intubation was carried out by the AC team compared with 35 (21.5%) by the non-AC team. CONCLUSION: Dedicated AC team offers better success rate for emergency tracheal intubation. Non-AC team attempted intubation in the majority of the cases before the arrival of the AC team. Increased intubation attempts are associated with increased incidence of adverse events. Equipment and patient factors also contributed to the adverse events. A multidisciplinary programme including the use of supraglottic devices may be helpful to improve the rate of success and minimise complications.


Assuntos
Manuseio das Vias Aéreas , Intubação Intratraqueal , Adulto , Serviço Hospitalar de Emergência , Humanos , Intubação Intratraqueal/efeitos adversos , Singapura/epidemiologia , Centros de Atenção Terciária
17.
J Ovarian Res ; 13(1): 113, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32958014

RESUMO

OBJECTIVE: To assess the anti-tumor activity and side effects of different dosages of paclitaxel (albumin binding type) (hereinafter referred to as nab-P) combined with Apatinib (hereinafter referred to as AP) in platinum-resistant ovarian cancer cell line and xenograft models. METHODS: SKOV-3/DDP cell line was selected as the research object in cytology experiment. Firstly, we divided it into three groups for experiments to explore the individual effects of nab-P and AP. a): Control group, blank control, no drug intervention; b): nab-P group, nab-P 40 µmol/l; c): AP group, AP 50 µmol/l (Drug doses were IC-50 values that detected by MTT assay). Apoptosis related protein (Bax, bcl-2), vascular related protein(p-VEGFR-2), invasion related protein (MMP-2) expression were detected by Western blot and Cellular immunofluorescence, the invasion ability of tumor cells were detected by Transwell and Cell scratch test. Based on these dates, secondly, establishing different doses of nab-P combined with Ap to explore the curative effect of combination therapy. a): Control group, blank control, no drug intervention; b): Group-1, nab-P 5 µmol/l + AP 10 µmol/l, c): Group-2, nab-P 4.5 µmol/l + AP 10 µmol/l, d): Group-3, nab-P 4 µmol/l + AP 10 µmol/l, e): nab-P group, nab-P 5 µmol/l, f): AP group, AP 10 µmol/l (MTT assay). The combination index was analyzed by Compusyn software, Western blot, Immunofluescence, Transwell and Cell scratch test also were also chose to observe of inhibition effect. Thirdly, we used xenograft models to verify the results of cytological experiments. Tumor-forming BALB/c female nude mice were randomly divided into 4 groups, a): Control group, no drug intervention, only saline injection, b): nab-P 20 mg/kg + AP 150 mg/kg, c): nab-P 18 mg/kg + AP 150 mg/kg, d): nab-P 16 mg/kg + AP 150 mg/kg (The doses were guided by the pharmaceutical manufacturers). The tumor growth curve was analyzed during the experiment. And the apoptosis related protein (Bax, bcl-2), angiogenesis related protein (CD31, p-VEGFR-2) and invasion related protein (MMP-2) were observed by Western blot, Immunofluescence and Immunohistochemistry to analysis the ant-tumor effects. The quality of life in nude mice were observed to analysed the drug-induced side effects. RESULT: In the separate medication section, (1) The IC-50 value of nab-P was 45.53 ± 4.06 µmol/l, while the AP was 50.66 ± 4.96 umol/L (48 h). (2) The expressions of bcl-2 (nab-P group, AP group), p-VEGFR-2 (AP group), MMP-2(nab-P group, AP group) were higher than Control group, while Bax (nab-P group, AP group) lower (P < 0.01). (3) The cell invasive ability was decreased after the nab-P and AP intervation (P < 0.01). In the combination medication section, (1) Compusyn showed the Combination index (Cl) were all below 1 (Cl < 1), that means nab-P and AP are synergism. (2) The combination IC-50 value was nab-P 5.28 µmol/l + AP 10.56 µmol/l (48 h). (3) In the detection of related protein expression, the combination of drugs can improve the anti-tumor effect, otherwise, after combined with AP, when nab-P were reduced dose in proper quantity, there were no obvious different in drug effect. (4) After reducing the doses of nab-P, the average food intake of nude mice increased from 4.50 g ± 0.17 to 5.55 g ± 0.13, and the one-hour activity increased from 6.11 min ±0.16 to 6.34 min ±0.13. CONCLUSION: nab-P, a chemotherapeutic agent, can play an anti-tumor role in platinum-resistant ovarian cancer, but it can cause adverse effects that increase with dose. When combined with AP, the two drugs have synergistic effect, which can improve the anti-tumor effects of single drug. In addition, when combined with AP, the doses of nab-P can be appropriately reduced under the standard of recommended to reduce the toxicity of chemotherapy drugs, without affecting the anti-tumor effect.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Paclitaxel/uso terapêutico , Piridinas/uso terapêutico , Animais , Antineoplásicos/farmacologia , Combinação de Medicamentos , Feminino , Humanos , Camundongos , Camundongos Nus , Neoplasias Ovarianas/patologia , Paclitaxel/farmacologia , Piridinas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
18.
J Nat Med ; 74(2): 434-440, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31960210

RESUMO

The predominant feature of type 2 diabetes is insulin resistance. Identifying a drug able to reduce insulin resistance is an urgent requirement. ent-3α-Formylabieta-8(14),13(15)-dien-16,12ß-olide had been identified as a new diterpene derivative which showed anticancer activity. This study explores the hypoglycemic effect of ent-3α-formylabieta-8(14),13(15)-dien-16,12ß-olide and studied its mechanism. The insulin response of HepG2 cells following ent-3α-formylabieta-8(14),13(15)-dien-16,12ß-olide treatment, as a model for liver cancer cells, was assessed. The results demonstrated that hyperglycemia resulted in a significant increase in the levels of insulin receptor substrate-1 (IRS-1) serine phosphorylation and decrease in Akt phosphorylation. High glucose also inhibited the phosphorylation of insulin-dependent GSK3ß. ent-3α-Formylabieta-8(14),13(15)-dien-16,12ß-olide treatment improved the effect of insulin on the phosphorylation of IRS-1 Ser307. In addition, this study demonstrated that the effect of ent-3α-formylabieta-8(14),13(15)-dien-16,12ß-olide was dependent on the activation of AMP-activated protein kinase. Collectively, experimental data indicated an association between insulin resistance and hyperglycemia in HepG2 cells, and that ent-3α-formylabieta-8(14),13(15)-dien-16,12ß-olide reduces IRS-1 Ser307 phosphorylation via activating AMPK, thereby decreasing the insulin signaling blockade.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Diterpenos/uso terapêutico , Células Hep G2/metabolismo , Insulina/metabolismo , Diterpenos/farmacologia , Humanos , Transdução de Sinais , Transfecção
19.
Materials (Basel) ; 12(22)2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31717524

RESUMO

The tunability of semi-conductivity in SrTiO3 single crystal substrates has been realized by a simple encapsulated annealing method under argon atmosphere. This high temperature annealing-induced property changes are characterized by the transmission spectra, scanning electron microscopy (SEM) and synchrotron-based X-ray absorption (XAS). We find the optical property is strongly influenced by the annealing time (with significant decrease of transmittance). A sub gap absorption at ~427 nm is detected which is attributed to the introduction of oxygen vacancy. Interestingly, in the SEM images, annealing-induced regularly rectangle nano-patterns are directly observed which is contributed to the conducting filaments. The XAS of O K-edge spectra shows the changes of electronic structure by annealing. Very importantly, resistance switching response is displayed in the annealed SrTiO3 single crystal. This suggests a possible simplified route to tune the conductivity of SrTiO3 and further develop novel resistance switching materials.

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