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21.
22.
N-benzhydrylpiperazine and 1,3,4-oxadiazoles are pharmacologically active scaffolds which exhibits significant inhibitory growth effects against various cancer cells, however, antiproliferation effects and the underlying mechanism for inducing apoptosis for aforementioned scaffolds addressing HeLa cancer cells remains uncertain. In this study, N-benzhydrylpiperazine clubbed with 1,3,4-oxadiazoles ( 4a–4h ) were synthesized, subsequently characterized using high resolution spectroscopic techniques and eventually evaluated for their antiproliferation potential by inducing apoptosis in HeLa cancer cells. The MTT assay screening results revealed that among all, compound 4d ( N-benzhydryl-4-((5-(4-aminophenyl)-1,3,4-oxadiazol-2-yl)methyl)piperazine) in particular, exhibited IC 50 value of 28.13 ± 0.21 μg/mL and significantly inhibited the proliferation of HeLa cancer cells in concentration-dependent manner. The in vitro anticancer assays for treated HeLa cells resulted in alterations in the cell morphology, reduction in colony formation, and inhibition of cell migration in concentration-dependent treatment. Furthermore, G2/M phase arrest, variations in the nuclear morphology, degradation of chromosomal DNA confirmed the ongoing apoptosis in treated HeLa cells. Increase in the expression of cytochrome C and caspase-3 confirmed the involvement of intrinsic mitochondrial pathway regulating the cell death. Also, elevation in reactive oxygen species level and loss of mitochondrial membrane potential signified that compound 4d induced apoptosis in HeLa cells by generating the oxidative stress. Therefore, compound 4d may act as a potent chemotherapeutic agent against human cervical cancer.  相似文献   
23.
Journal of Physiology and Biochemistry - Gamma-tocotrienol (GTT) and hydroxychavicol (HC) exhibit anticancer activity in glioma cancer cells, where the combination of GTT + HC was shown to be more...  相似文献   
24.
Two DNA fingerprinting techniques, random amplified polymorphic DNA (RAPD) and inter-retrotransposon amplified polymorphism (IRAP), were used to characterize somaclonal variants of banana. IRAP primers were designed on the basis of repetitive and genome-wide dispersed long terminal repeat (LTR) retrotransposon families for assessing the somaclonal variation in 2Musa clones resistant and susceptible toFusarium oxysporum f. sp.cubense race 4. RAPD markers successfully detected genetic variation within and between individuals of the clones. IRAP makers amplified either by a single primer or a combination of primers based on LTR orientation successfully amplified different retrotransposons dispersed in theMusa genome and detected new events of insertions. RAPD markers proved more polymorphic than IRAP markers. Somaclonal variation seems to be the result of numerous indels occurring genome-wide accompanied by the activation of retroelements, as a result of stress caused by micropropagation. It is concluded that characterization of the somaclonal variants requires more than one DNA marker system to detect variation in diverse components of the genome.  相似文献   
25.

Background

Misclassification of patients as low cardiovascular risk (LCR) remains a major concern and challenges the efficacy of traditional risk markers. Due to its strong association with cholesterol acceptor capacity, high-density lipoprotein (HDL) size has been appointed as a potential risk marker. Hence, we investigate whether HDL size improves the predictive value of HDL-cholesterol in the identification of carotid atherosclerotic burden in individuals stratified to be at LCR.

Methods and Findings

284 individuals (40–75 years) classified as LCR by the current US guidelines were selected in a three-step procedure from primary care centers of the cities of Campinas and Americana, SP, Brazil. Apolipoprotein B-containing lipoproteins were precipitated by polyethylene glycol and HDL size was measured by dynamic light scattering (DLS) technique. Participants were classified in tertiles of HDL size (<7.57; 7.57–8.22; >8.22 nm). Carotid intima-media thickness (cIMT) <0.90 mm (80th percentile) was determined by high resolution ultrasonography and multivariate ordinal regression models were used to assess the association between cIMT across HDL size and levels of lipid parameters. HDL-cholesterol was not associated with cIMT. In contrast, HDL size >8.22 nm was independently associated with low cIMT in either unadjusted and adjusted models for age, gender and Homeostasis Model Assessment 2 index for insulin sensitivity, ethnicity and body mass index (Odds ratio 0.23; 95% confidence interval 0.07–0.74, p = 0.013).

Conclusion

The mean HDL size estimated with DLS constitutes a better predictor for subclinical carotid atherosclerosis than the conventional measurements of plasma HDL-cholesterol in individuals classified as LCR.  相似文献   
26.
A trypsin inhibitor purified from the seeds of the Manila tamarind, Pithecellobium dulce (PDTI), was studied for its effects on growth parameters and developmental stages of  Helicoverpa armigera. PDTI exhibited inhibitory activity against bovine trypsin (~86%; ~1.33 ug/ml IC50). The inhibitory activity of PDTI was unaltered over a wide range of temperature, pH, and in the presence of dithiothreitol. Larval midgut proteases were unable to digest PDTI for up to 12 h of incubation. Dixon and Lineweaver–Burk double reciprocal plots analysis revealed a competitive inhibition mechanism and a Ki of ~3.9 × 10?8 M. Lethal dose (0.50% w/w) and dosage for weight reduction by 50% (0.25% w/w) were determined. PDTI showed a dose‐dependent effect on mean larval weight and a series of nutritional disturbances. In artificial diet at 0.25% w/w PDTI, the efficiency of conversion of ingested food, of digested food, relative growth rate, and growth index declined, whereas approximate digestibility, relative consumption rate, metabolic cost, consumption index, and total developmental period were increased in larvae. This is the first report of antifeedant and antimetabolic activities of PDTI on midgut proteases of  H. armigera.  相似文献   
27.
Russian Journal of Bioorganic Chemistry - Pyridazines hold considerable interest relative to pharmacologically active molecules. The pyridazine compounds are exhibited different types of...  相似文献   
28.
This work tackles the problem of reducing the power consumption of the OLSR routing protocol in vehicular networks. Nowadays, energy-aware and green communication protocols are important research topics, specially when deploying wireless mobile networks. This article introduces a fast automatic methodology to search for energy-efficient OLSR configurations by using a parallel evolutionary algorithm. The experimental analysis demonstrates that significant improvements over the standard configuration can be attained in terms of power consumption, with no noteworthy loss in the QoS.  相似文献   
29.
A 58 year old male, known case of type 2 diabetes and hypertension, had undergone implantation of a dual chamber pacemaker(DDDR) in 2007 for complaints of recurrent syncope and trifascicular block with a normal ejection fraction andnormal coronaries. His post implantation parameters were normal at that time.He now presented to our pacemaker clinic where his ECG done showed two types o fpaced complexes. The first few complexes were consistent with atrial sensed right ventricular apical pacing with left superior axis. Later complexes showed loss of atrial sensing with pacing from right ventricular outflow tract(inferior axis) with subtle oscillation in it''s axis. On application of magnet, two pacemaker spikes were visible withinterspike interval of 120 ms and paced complexes with inferior axis starting from the first spike suggesting that the atrial lead was responsible for RVOT depolarization. On interrogation of the pacemaker, atrial EGM showed sensed activity from atrium followed by large sensed ventricular complex. Fluoroscopy confirmed that the atrial lead was dislodged and was intermittently prolapsing into the RVOT. Since the patient was asymptomatic, he refused any intervention and subsequentlyhis atrial lead was switched off by telemetry. The above case signifies that asymptomatic lead dislodgement is no talways manifested as loss of capture and even subtle variation of the axis o fthe paced complexes can provide us with a clue that can be confirmed by telemetry of the pacemaker and fluoroscopy.  相似文献   
30.
The intraerythrocytic malaria parasite exerts tight control over its ionic composition. In this study, a combination of fluorescent ion indicators and 36Cl flux measurements was used to investigate the transport of Cl and the Cl-dependent transport of “H+-equivalents” in mature (trophozoite stage) parasites, isolated from their host erythrocytes. Removal of extracellular Cl, resulting in an outward [Cl] gradient, gave rise to a cytosolic alkalinization (i.e. a net efflux of H+-equivalents). This was reversed on restoration of extracellular Cl. The flux of H+-equivalents was inhibited by 4,4′-diisothiocyanostilbene-2,2′-disulfonic acid and, when measured in ATP-depleted parasites, showed a pronounced dependence on the pH of the parasite cytosol; the flux was low at cytosolic pH values < 7.2 but increased steeply with cytosolic pH at values > 7.2. 36Cl influx measurements revealed the presence of a Cl uptake mechanism with characteristics similar to those of the Cl-dependent H+-equivalent flux. The intracellular concentration of Cl in the parasite was estimated to be ∼48 mm in situ. The data are consistent with the intraerythrocytic parasite having in its plasma membrane a 4,4′-diisothiocyanostilbene-2,2′-disulfonic acid-sensitive transporter that, under physiological conditions, imports Cl together with H+-equivalents, resulting in an intracellular Cl concentration well above that which would occur if Cl ions were distributed passively in accordance with the parasite''s large, inwardly negative membrane potential.  相似文献   
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