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Adansonia digitata L. also known as African baobab is one of the most important fruit-producing trees, widely distributed in the African continent. Baobab fruits are known to possess potential health benefits and nutritional value. This study aimed to holistically dissect the metabolome of A. digitata fruits using a novel comparative protocol using three different analytical platforms. Ultra high performance liquid chromatography coupled to high-resolution tandem mass spectrometry (UHPLC-HRMS/MS), and headspace solid-phase microextraction/gas chromatography coupled to mass spectrometry (HS-SPME/GC-MS) were respectively employed for phytonutrients and aroma profiling, whereas GC-MS post silylation provided an overview of nutrients i.e., sugars. UHPLC-HRMS/MS analysis allowed for the assignment of 77 metabolites, among which 50% are reported for the first time in the fruit. While GC-MS of silylated and aroma compounds led to the identification of 74 and 16 compounds, respectively. Finally, NMR-based metabolite fingerprinting permitted the quantification of the major metabolites for future standardization. In parallel, in vivo antidiabetic potential of the baobab fruit using a streptozotocin (STZ) induced diabetic rat model was assessed. Histopathological and immune-histochemical investigations revealed hepatoprotective and renoprotective effects of A. digitata fruit along with mitigation against diabetes complications. Moreover, the administration of A. digitata fruits (150 mg kg−1) twice a week lowered fasting blood glucose levels.

Metabolites profiling of Adansonia digitata L. in relation to its biological activity.  相似文献   
63.
Microtubules have become an appealing target for anticancer drug development including mainly colchicine binding site inhibitors (CBSIs). A new series of novel trimethoxypyridine derivatives were designed and synthesized as tubulin targeting agents. In vitro anti-proliferative activities of the tested compounds compared to colchicine against hepatocellular carcinoma (HepG-2), colorectal carcinoma (HCT-116), and breast cancer (MCF-7) was carried out. Most of compounds showed significant cytotoxic activities. Compounds Vb, Vc, Vf, Vj and VI showed superior anti-proliferative activities to colchicine. Where compound VI showed IC50 values of 4.83, 3.25 and 6.11 μM compared to colchicine (7.40, 9.32, 10.41 μM) against HCT 116, HepG-2 and MCF-7, respectively. The enzymatic activity against tubulin enzyme was carried out for the compounds that showed high anti-proliferative activity. Also, compound VI exhibited the highest tubulin polymerization inhibitory effect with an IC50 value of 8.92 nM compared to colchicine (IC50 value = 9.85 nM). Compounds Vb, Vc, Vf, Vj, & VIIIb showed promising activities with IC50 values of 22.41, 17.64, 20.39, 10.75, 31.86 nM, respectively. Cell cycle and apoptosis test for compound VI against HepG-2 cells, indicated that compound VI can arrest cell cycle at G2/M phase, and can cause apoptosis at pre-G1 phase, with high apoptotic effect 18.53%. Molecular docking studies of the designed compounds confirmed the essential hydrogen bonding with CYS241 beside the hydrophobic interaction at the binding site compared to reference compounds which assisted in the prediction of the structure requirements for the detected antitumor activity.

Interaction of compounds VI (IC50 = 8.92 nM) (A) and Vj (IC50 = 10.75 nM) (B) with key amino acids of CBS.  相似文献   
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BackgroundThe aim of this review was to evaluate the most used suture materials with regards to their inflammatory response, their bacterial adhesion, and their physical properties when used to close oral wounds.MethodsFour databases (PubMed, Scopus, Dentistry & Oral Sciences, and OVID) were searched to retrieve relevant studies from January 1, 2000, to January 31, 2020.ResultsOut of the 269 articles, only 13 studies were selected as they were relevant and met the systematic review's protocol. These studies showed that almost all suture materials studies (catgut, polyglycolic acid [PGA] sutures, nylon, expanded polytetrafluoroethylene, and silk sutures) caused bacterial adherence and tissue reaction. In nylon and chromic catgut, the number of bacteria accumulated was lowest. Silk and nylon were found to be more impacted than catgut and PGA in terms of physical characteristics such as tensile strength. PGA, on the other hand, was said to be the most susceptible to knot unwinding.ConclusionsFollowing an oral surgical operation, all sutures revealed varied degrees of irritation and microbial accumulation. Nonresorbable monofilament synthetic sutures, however, exhibited less tissue response and less microbial accumulation.  相似文献   
68.
BackgroundSickle cell disease (SCD) results in severe complications, such as anaemia and pain episodes. Hydroxyurea (HU) is efficacious in SCD, yet adherence remains low.ObjectiveTo assess the relationship of HU adherence to health care utilization and patients’ characteristics.MethodsThis is a 5-year retrospective chart review. Patients’ demographics and medical history were collected from the electronic medical record (EMR). HU adherence was evaluated using foetal haemoglobin “HbF%”, mean corpuscular volume “MCV”, and absolute neutrophil count “ANC”. Age groups included children (<12 years), adolescents (12–17 years), and young adults (≥18 years).ResultsA total of 113 SCD patients on HU were included (median age 14 years, IQR 10–20; 50% female; 88% HbSS). Young adults had significantly higher HU adherence compared to adolescents and children, including higher median HbF% (24.2 vs. 12.4 vs. 8.6, p = .003), MCV (fl) (106.4 vs. 96.2 vs. 95.4, p = .01) and lower ANC (103/ml) (3.25 vs. 4.9 vs. 4.2, p = .01), respectively. Patients with chronic pain had lower HU adherence (HbF% 15.3 vs. 10.7, p = .04; ANC 3.6 vs. 6.3, p = .002; MCV 102.3 vs. 93.1, p = .1). Patients with higher HbF or MCV and lower ANC had significantly less frequent emergency room visits (rs=–0.26, p = .01; rs=–0.23, p = .01; rs=0.24, p = .01) and hospitalizations (rs=–0.27, p = .01; rs=–0.31, p = .01; rs=0.21, p = .02) as well as shorter length of stays (rs=–0.27, p = .0045; rs=–.34, p = 0.004; rs=0.23, p = .02), respectively. Similar trends in HU adherence and health care utilization were seen in subgroup analysis of only HbSS patients. There was no significant association of HU adherence to patients’ sex, socio-economic status, distance from hospital, and HU duration.ConclusionsYoung adults with SCD had significantly higher HU adherence compared to children and adolescents. Patients with lower HU adherence and/or chronic pain had increased health care utilization. Future studies examining barriers to adherence and evaluating interventions to optimize HU adherence in SCD are warranted.

KEY MESSAGES

  1. Young adults with SCD had significantly higher HU adherence, as reflected in their laboratory markers, compared to children and adolescents.
  2. Patients with higher HU adherence and/or those without chronic pain had lower or less frequent health care utilization.
  3. No significant association of HU adherence to patients’ sex, socio-economic status and distance from hospital.
  相似文献   
69.
GADD45β基因表达诱导对不同p53状态的肝癌细胞作用   总被引:1,自引:0,他引:1  
目的:体外合成GADD45β基因全序列表达质粒后,研究GADD45β基因表达诱导对呈不同p53状态的肝癌细胞的作用及可能机制。方法:采用RT-PCR法获得GADD45β基因全序列,插入pDrive穿梭克隆载体和pIRES2-EGFP荧光表达载体后大量扩增获得DNA,结合p53全基因表达质粒pp53-EGFP转染HepG2、Hep3B细胞后,以[^3H]胸腺嘧啶脱氧核苷掺入法(^3H—Tdr)和细胞克隆形成法分析DNA合成变化及细胞生长能力;以双抗体夹心ELISA法测定TGF-β1表达变化。结果:成功合成GADD45β基因全序列和表达质粒,通过流式细胞仪收集转染阳性的荧光表达细胞能显著提高转染效率;转染GADD45β后.具有野生型p53基因的HepG2细胞的细胞克隆形成能力和DNA合成能力明显受到抑制,细胞凋亡明显增加,TGF-β1的表达亦明显受抑。与之相反,缺失p53基因的Hep3B需要同时共转染p53基因后,方出现抑制效应。结论:GADD45β基因能够有效抑制肝癌细胞的生长.其功能需要完整p53基因的辅助和(或)调控。GADD45表达和(或)功能异常,导致p53介导的DNA损伤修复途径异常或阻断,是肝脏细胞恶性转化及形成肿瘤的可能机制。  相似文献   
70.

Background

Surgery for renal cell carcinoma (RCC) patients with inferior vena cava (IVC) thrombus above the hepatic veins is technically complex and associated with an increased risk of perioperative morbidity and mortality. However, minimal data exist that describe contemporary perioperative outcomes at major referral centers or the prognostic factors associated with poor outcomes.

Objective

To determine the preoperative predictors of major complications and 90-d mortality after surgery in RCC patients who have IVC thrombus above the hepatic veins.

Design, setting, and participants

We reviewed medical records of all RCC patients who had IVC tumor thrombus above hepatic veins and had had surgery between January 2000 and December 2012 at the Mayo Clinic, M.D. Anderson Cancer Center, University of Texas Southwestern Medical Center, and the University of Wisconsin Hospital.

Outcome measurement and statistical analysis

Major complications recorded were defined as ≥3A according to the Clavien-Dindo system within 90 d of surgery. Univariate and multivariate analyses were used to evaluate associations of preoperative variables with risk of major complications or 90-d mortality.

Results and limitations

A total of 162 patients were identified for study (level 3, 4 in 69, 93 patients, respectively, according to the Neves classification). Cardiopulmonary bypass was used in 60 of 162 patients (37.5%), and 40 patients (24.7%) had preoperative angioembolization. Major complications were reported in 55 patients (34.0%), with the most common being respiratory, cardiac, and hematologic issues. After multivariate analysis, preoperative systemic symptoms and level 4 thrombus were independently associated with increased risk of major complications. Mortality was reported in 17 patients (10.5%) within 90 d after surgery. After multivariate analysis, Eastern Cooperative Oncology Group (ECOG) performance status (PS) and low serum albumin were preoperative factors independently associated with increased risk of 90-d mortality.

Conclusions

Contemporary perioperative mortality and major complication rates for RCC patients who have upper-level thrombus are 10% and 34%, respectively. Patients who have ECOG PS >1 or low serum albumin have increased risk for perioperative mortality.  相似文献   
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