共查询到20条相似文献,搜索用时 31 毫秒
1.
Nigel Irwin Pamela FrizelleFinbarr P.M. O'Harte Peter R. Flatt 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Cholecystokinin (CCK) is a gastrointestinal hormone that has been proposed as a potential therapeutic option for obesity–diabetes. As such, (pGlu-Gln)-CCK-8 is an N-terminally modified CCK-8 analogue with improved biological effectiveness over the native peptide.Methods
The current study has examined the in vitro stability, biological activity and in vivo therapeutic applicability of a novel second generation mini-PEGylated form of (pGlu-Gln)-CCK-8, (pGlu-Gln)-CCK-8[mPEG].Results
(pGlu-Gln)-CCK-8[mPEG] was completely resistant to enzymatic degradation and in addition displayed similar insulinotropic (p < 0.05 to p < 0.001) and satiating effects (p < 0.01 to p < 0.001) as (pGlu-Gln)-CCK-8. This confirmed the capability of (pGlu-Gln)-CCK-8[mPEG] to bind to and activate the CCK receptor. Sub-chronic twice daily injection of (pGlu-Gln)-CCK-8[mPEG] in high fat fed mice for 35 days significantly decreased body weight gain (p < 0.05), food intake (p < 0.01 to p < 0.001) and triacylglycerol deposition in liver (p < 0.001) and muscle (p < 0.001). Furthermore, (pGlu-Gln)-CCK-8[mPEG] markedly improved intraperitoneal glucose tolerance (p < 0.05) and insulin sensitivity (p < 0.001). Despite this therapeutic profile, once daily injection of (pGlu-Gln)-CCK-8[mPEG] in high fat fed mice for 33 days, at the same dose, was not associated with alterations in food intake and body weight. In addition, metabolic responses to exogenous glucose and insulin injection were similar to saline treated controls.Conclusion
These studies emphasise the therapeutic potential of (pGlu-Gln)-CCK-8[mPEG] and similar molecules.General significance
A more detailed analysis of the dose and administration schedule employed for (pGlu-Gln)-CCK-8[mPEG] could provide a novel and effective compound to treat obesity–diabetes. 相似文献2.
Ashutosh Pandey Swati Chandra Lalit Kumar Singh Chauhan Gopeshwar Narayan Debapratim Kar Chowdhuri 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Amorphous silica nanoparticles (aSNPs) are used for various applications including food industry. However, limited in vivo studies are available on absorption/internalization of ingested aSNPs in the midgut cells of an organism. The study aims to examine cellular uptake of aSNPs (< 30 nm) in the midgut of Drosophila melanogaster (Oregon R+) owing to similarities between the midgut tissue of this organism and human and subsequently cellular stress response generated by these nanoparticles.Methods
Third instar larvae of D. melanogaster were exposed orally to 1–100 μg/mL of aSNPs for 12–36 h and oxidative stress (OS), heat shock genes (hsgs), membrane destabilization (Acridine orange/Ethidium Bromide staining), cellular internalization (TEM) and apoptosis endpoints.Results
A significant increase was observed in OS endpoints in the midgut cells of exposed Drosophila in a concentration- and time-dependent manner. Significantly increased expression of hsp70 and hsp22 along with caspases activation, membrane destabilization and mitochondrial membrane potential loss was also observed. TEM analysis showed aSNPs-uptake in the midgut cells of exposed Drosophila via endocytic vesicles and by direct membrane penetration.Conclusion
aSNPs after their internalization in the midgut cells of exposed Drosophila larvae show membrane destabilization along with increased cellular stress and cell death.General significance
Ingested aSNPs show adverse effects on the cells of GI tract of the exposed organism thus their industrial use as a food-additive may raise concern to human health. 相似文献3.
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Sawsan Al-Sinani Mohammed Othman Hassan Fahad Zadjali Said Al-Yahyaee Sulayma Albarwani Syed Rizvi Deepali Jaju Anthony Comuzzie Venkata Saroja Voruganti Riad Bayoumi 《Gene》2014
Objectives
This study examined the utility of a family-based model for replicating the results of genome-wide association studies (GWAS) of type 2 diabetes (T2D).Methods and results
In a total of 232 members of a large consanguineous Omani Arab pedigree (age: 16–80 years), there were 27 diabetics and 50 prediabetics (17 with impaired fasting glucose and 33 with impaired glucose tolerance). All 232 individuals underwent anthropometric and biochemical investigations and genotyped for 14 known common gene variants of modest effect on T2D risk. Power analysis at a LOD score of 3, gave 80% power to locate a single specific locus that accounts for 52% of the total phenotypic variation. Measured genotype analysis (MGA) was used to determine heritability of various quantitative traits (QTs) which ranged 25–56%. Using MGA, some common gene variants were found to have little (< 5%) but significant impact on the heritability of T2D related QTs [KCNJ11 (rs5219), p = 0.004]; [IGF2BP2 (rs4402960), p = 0.02]; [SLC30A8 (rs13266634), p = 0.05]; [CAPN10 (rs2975760), p = 0.031]; [FTO (rs8050136), p = 0.023]; [FTO (rs9939609), p = 0.018] and [SLC30A8 (rs13266634), p = 0.05]. Sib-TDT analysis showed that some gene variants were significantly associated with T2D risk but didn't reach the level of significance after Bonferroni correction [KCNJ11 (rs5219), p = 0.047] and [CAPN10 (rs41266971), p = 0.035].Conclusion
We have demonstrated that, in principle, a family-based model with minor limitations could be used to replicate some of the results of large GWAS case–control studies. This model could successfully be applied for the future discovery, by deep sequencing, of rare gene variants. 相似文献5.
Background
The single-gene approach in association studies of polygenic diseases such as acute myocardial infarction (AMI) is likely to provide limited value. Interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and interleukin-10 (IL-10) plasma levels may be genetically influenced.Aim
We evaluate the impact of single nucleotide polymorphism of the promoter region of these genes, as well as reciprocal interaction of these genes with ST-elevation of myocardial infarction (STEMI).Methods
In a case–control study 500 STEMI patients and 500 age- and sex-matched controls were studied. Three single-nucleotide polymorphism genotypes were evaluated by polymerase chain reaction and restriction enzyme analysis and assessed their association with STEMI. The synergistic effects of IL-6, TNF-α and IL-10 gene polymorphisms were evaluated by using logistic regression analysis.Results
We found that IL-6 and TNF-α concentrations of studied population were significantly different (p < 0.0001) in each genotype of IL-6 − 174G>C and TNF-α − 308G>A gene polymorphisms respectively. A significant association was found in multivariate analysis for the IL-6 − 174G>C [odds ratio (OR): 0.390; 95% confidence interval (CI): 0.176–0.865, p = 0.020] and TNF-α − 308G>A [OR: 0.372; 95% CI: 0.171–808, p = 0.012] gene polymorphisms with STEMI. In contrast, IL-10 − 592C>A gene polymorphism was no longer significant in the multivariate model (OR: 0.678; 95% CI: 0.288 to 1.594, p = 0.373) whereas significant in univariate analysis (OR: 0.697; 95% CI: 0.523–0.929, p = 0.014).Conclusions
Our findings suggest that IL-6, TNF-α and IL-10 gene polymorphisms all contribute in the association with STEMI whereas the association persisted only for IL-6 and TNF-α but not for IL-10 gene polymorphism with this disease in the multivariate analysis. 相似文献6.
Rosa María Agra Elvis Teijeira-Fernández Domingo Pascual-Figal Sánchez-Más Jesús Ángel Fernández-Trasancos Juan Sierra José Ramón González-Juanatey Sonia Eiras 《Life sciences》2014
Aims
S100A9 is a new inflammatory marker associated with obesity and cardiovascular disease. Because epicardial adipose tissue (EAT) is an inflammatory source in coronary artery disease (CAD), our aim was to evaluate the S100A9 levels in plasma and EAT and its association with CAD.Main methods
Blood, EAT and/or subcutaneous adipose tissue (SAT) biopsies were obtained from 89 patients undergoing elective cardiac surgery. Plasma S100A9 and adiponectin were analyzed by enzyme-linked immunosorbent assay (ELISA) and mRNA expression in both fat pads and were measured by real-time polymerase chain reaction (PCR).Key findings
Our results have shown higher levels of plasma S100A9 in patients with CAD than those without (29 [10–50] vs. 17 [3–28] ng/mL; p = 0.007). They were dependent on the number of injured-coronaries (p = 0.002) with tendency toward negative association with plasma adiponectin (p = 0.139). Although EAT expressed higher levels than SAT and their levels were higher in CAD patients, this last difference did not reach statistical significance. However, there was a positive correlation between neutrophils and EAT S100A9 expression (p = 0.007) that may reveal an increase of neutrophil filtration on this fat pad.Significance
Plasma S100A9 levels are increased in chronic CAD. The absence of differences regarding EAT S100A9 expression levels indicates a differential inflammatory process between fat tissues and blood in CAD process. 相似文献7.
Christine M.A. Martin Nigel IrwinPeter R. Flatt Victor A. Gault 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Rapid enzymatic degradation of the incretin hormone, glucose-dependent insulinotropic polypeptide (GIP), limits therapeutic use of the native peptide for diabetes. However, enzymatically stable analogues of GIP, such as (d-Ala2)GIP, have been generated, but are still susceptible to renal filtration.Methods
The present study examines the in vitro and in vivo biological actions of a novel, acylated GIP analogue, (d-Ala2)GIP[Lys37PAL].Results
In BRIN-BD11 cells, (d-Ala2)GIP[Lys37PAL] concentration-dependently stimulated (p < 0.05 to p < 0.001) insulin secretion at 5.6 and 16.7 mM glucose. Intraperitoneal administration of (d-Ala2)GIP[Lys37PAL] to normal mice 8 h prior to a glucose load significantly reduced (p < 0.05) the overall glycaemic excursion compared to controls, and increased (p < 0.001) the insulinotropic response compared to (d-Ala2)GIP and saline treated high fat control mice. Once daily administration of (d-Ala2)GIP[Lys37PAL] for 21 days in high fat fed mice did not affect energy intake, body weight or fat deposition. However, circulating blood glucose was significantly lower (p < 0.05) accompanied by increased (p < 0.05) insulin concentrations by day 21. In addition, (d-Ala2)GIP[Lys37PAL] treatment significantly (p < 0.01) reduced the overall glycaemic excursion and increased pancreatic insulin content (p < 0.05) and the insulinotropic response (p < 0.01) to an exogenous glucose challenge on day 21. Chronic treatment with (d-Ala2)GIP[Lys37PAL] did not result in resistance to the metabolic effects of a bolus injection of native GIP. Finally, insulin sensitivity was significantly improved (p < 0.001) in (d-Ala2)GIP[Lys37PAL] treated mice compared to high fat controls.Conclusions
These data confirm that (d-Ala2)GIP[Lys37PAL] is a stable, long-acting potent GIP agonist.General significance
(d-Ala2)GIP[Lys37PAL] may be suitable for further evaluation and future clinical development. 相似文献8.
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10.
Éder Ricardo Petry Vinicius Fernandes Cruzat Thiago Gomes Heck Jaqueline Santos Moreira Leite Paulo Ivo Homem de Bittencourt Jr. Julio Tirapegui 《Life sciences》2014
Aims
We hypothesized that oral l-glutamine supplementations could attenuate muscle damage and oxidative stress, mediated by glutathione (GSH) in high-intensity aerobic exercise by increasing the 70-kDa heat shock proteins (HSP70) and heat shock factor 1 (HSF1).Main methods
Adult male Wistar rats were 8-week trained (60-min/day, 5 days/week) on a treadmill. During the last 21 days, the animals were supplemented with either l-alanyl-l-glutamine dipeptide (1.5 g/kg, DIP) or a solution containing the amino acids l-glutamine (1 g/kg) and l-alanine (0.67 g/kg) in their free form (GLN + ALA) or water (controls).Key findings
Plasma from both DIP- and GLN + ALA-treated animals showed higher l-glutamine concentrations and reduced ammonium, malondialdehyde, myoglobin and creatine kinase activity. In the soleus and gastrocnemius muscle of both supplemented groups, l-glutamine and GSH contents were increased and GSH disulfide (GSSG) to GSH ratio was attenuated (p < 0.001). In the soleus muscle, cytosolic and nuclear HSP70 and HSF1 were increased by DIP supplementation. GLN + ALA group exhibited higher HSP70 (only in the nucleus) and HSF1 (cytosol and nucleus). In the gastrocnemius muscle, both supplementations were able to increase cytosolic HSP70 and cytosolic and nuclear HSF1.Significance
In trained rats, oral supplementation with DIP or GLN + ALA solution increased the expression of muscle HSP70, favored muscle l-glutamine/GSH status and improved redox defenses, which attenuate markers of muscle damage, thus improving the beneficial effects of high-intensity exercise training. 相似文献11.
Hidehiko Akiyama Masahiro Endo Taei Matsui Itsurou Katsuda Nobuhiko Emi Yasuko Kawamoto Takaaki Koike Hidehiko Beppu 《Biochimica et Biophysica Acta (BBA)/General Subjects》2011
Background
Agaricus blazei Murrill (ABM) has been shown to exhibit immunostimulatory and anti-cancer activities; however, its mechanism of action is poorly understood. We recently found that the diffusible fraction of hot-water extract of ABM exhibits anti-tumor activity toward leukemic cells, and identified it as agaritine, a hydrazine-containing compound. In the present study, we examined the morphological and cytochemical effects of agaritine on U937 cells to elucidate the tumoricidal mechanism of agaritine.Methods
Surface expression of phosphatidylserine (evaluated by annexin V binding), Fas antigen, DNA cleavage using TUNEL staining, changes in caspase activities and cytochrome c release, before and after treatment with agaritine, were examined using U937 cells.Results
Nuclear damage, DNA fragmentation, was observed by Wright–Giemsa, TUNEL staining and agarose gel electrophoresis when U937 cells were incubated with 10 μg/mL of agaritine for 48 h. Flow cytometric analysis indicated that agaritine augments the proportion of annexin V-positive U937 cells without significant change in Fas antigen expression. Activities of caspase-3, -8 and -9 were gradually increased after the addition of agaritine. In the presence of caspase-3 or granzyme B inhibitor, except for the caspase-8 inhibitor, annexin V expression was significantly decreased, suggesting that mainly caspase-3 and -9 participate in the apoptotic pathway. Furthermore, cytochrome c release was detected by western blotting analysis after agaritine treatment.Conclusions
These results strongly suggest that the ABM constituent agaritine moderately induces apoptosis in U937 leukemic cells via caspase activation through cytochrome c release from mitochondria.General significance
This is the first report suggesting that the anti-tumor effect of agaritine is mediated through apoptosis. The present results might provide helpful suggestions for the design of anti-tumor drugs toward leukemia patients. 相似文献12.
Purpose
Fibromyalgia (FM) syndrome is a form of non-articular rheumatism characterized by long term and widespread musculoskeletal pain, morning stiffness, sleep disturbance, paresthesia, and pressure hyperalgesia at characteristic sites, called soft tissue tender points. The etiology of FM is still obscure. Genetic factors may predispose individuals to FM. Cytokines may play a role in the pathophysiology of FM. The aim of this study was to investigate the interleukin-4 (IL-4) 70 bp VNTR variations in Turkish patients with FM and evaluate if there was an association with clinical features, especially between these polymorphisms.Methods
The study included 300 patients with FM and 270 healthy controls. Genomic DNA was isolated and genotyped using polymerase chain reaction (PCR) for the IL-4 gene 70 bp VNTR polymorphisms.Results
There was statistically significant difference between the groups with respect to IL-4 genotype distribution and allele frequencies (p < 0.0001). The homozygous P1P1 genotype and P1 allele were significantly higher in FM patients than in healthy controls (p = 0.04; OR: 3.25, 95% CI: 1–10, p < 0.0001; OR:4.84, 95% CI:3–7.7). There was not any difference between the groups respect to IL-4 genotype distribution and allele frequencies (p > 0.05) and clinical characteristics.Conclusion
Our findings suggest that there is an association of IL-4 gene 70 bp VNTR polymorphism with susceptibility of a person for development of FM. As a result, further studies are necessary to determine whether IL-4 may be a genetic marker for FM in the Turkish population. 相似文献13.
Mei Jiang Lei Lv Hairong Wang Xuelian Yang Haifeng Ji Fei Zhou Wei Zhu Liying Cai Xiaju Gu Jian Sun Qiang Dong 《Gene》2012
Purpose
In the past decade, a number of case–control studies have been carried out to investigate the relationship between ABCA1 polymorphisms and Alzheimer's disease (AD). However, these studies have yielded contradictory results. To investigate this inconsistency, a meta-analysis was performed.Methods
Databases including PubMed, Web of Science, EMBASE and CNKI were searched to find relevant studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association.Results
A total of 13 case–control studies, involving 6214 patients and 6034 controls for ABCA1 polymorphisms were included. In a combined analysis, the summary per-allele odds ratio for AD of the 219 K was 1.03 (95% CI: 0.93–1.14, p = 0.56). A meta-analysis of studies on the 883 M and 1587 K variant showed no significant overall association with AD, yielding a per-allele odds ratio of 1.10 (95% CI: 0.96–1.26, p = 0.16), and 1.09 (95% CI: 0.97–1.24, p = 0.16) respectively. Similar results were also found for heterozygous and homozygous. In the subgroup analysis by ethnicity, sample size, APOE status and onset type, no significant associations were found in almost all genetic models.Conclusions
In summary, there was no significant association detected between ABCA1 R219K, I883M and R1587K polymorphisms and risk for AD. 相似文献14.
José Eduardo Baroneza Alexandre Godoy-Santos Bruno Ferreira Massa Francielle Boçon de Araujo Munhoz Túlio Diniz Fernandes Maria Cristina Leme Godoy dos Santos 《Gene》2014
Purpose
Posterior tibial tendon (PTT) is particularly vulnerable and its insufficiency is recognized as the main cause of adult acquired flatfoot. Some patients have a predisposition without clinically recognized cause, suggesting that individual characteristics play an important role in tendinopathy. The objective of the present study is to investigate the association of − 519 (rs1144393) matrix metalloproteinase-1 (MMP-1) polymorphism and the − 1607 (rs1799750) and − 519 MMP-1 haplotypes and risk of PTT dysfunction.Methods
The test group included 50 females who presented PTT dysfunction Grade 2 or 3, and who were submitted to surgical treatment, with histopathological examination of the tendon and magnetic resonance image (MRI) confirming tendinopathy, while the control group was 100 asymptomatic women who present intact PTT at MRI. We analyzed functional polymorphisms MMP-1 and their haplotypes using polymerase chain reaction and restriction fragment length analysis.Results
There was a significant difference in the presence of the different alleles and genotypes between the control group and test group for the MMP-1 gene (p ≤ 0.01). The G allele of the − 519 MMP-1 polymorphism increased susceptibility to degeneration in the PTT tendon and seems to be a genetic risk factor. Global haplotype analysis indicated a significant difference between both groups (p < 0.0001). Haplotypes G–2G and A–2G had statistically significant risk effect on PTT insufficiency. G–2G, p < 0.001; OR = 5.72 (CI, 2.84–11.52) and A–2G p = 0.002, OR = 3.95 (CI, 1.65–9.44).Conclusion
According to our results, − 519 MMP-1 isolated and − 1607/− 519 MMP-1 haplotypes are associated to tendinopathy in posterior tibial tendon. 相似文献15.
Objective
The aim of this study was to determine whether ADAM33 (a disintegrin and metalloproteinase domain 33) polymorphisms confer susceptibility to asthma in different populations.Methods
We performed a meta-analysis on the association between the ADAM33 S2, ST+4, F+1, S1, and V4 polymorphisms and asthma.Results
Thirteen studies in ten reports, which included 4942 patients and 7933 controls, were available for the meta-analysis. Meta-analysis stratified by ethnicity indicated an association between the ADAM33 S2 2 allele and asthma in Europeans (OR = 0.912, 95% CI = 0.851–0.977, p = 0.009). Meta-analysis revealed an association between asthma and the ADAM33 ST+4 2 allele (OR = 0.783, 95% CI = 0.762–0.999, p = 0.048). Stratification by ethnicity indicated an association between the ADAM33 ST+4 polymorphism and asthma in Asians. Stratification by age indicated an association between the ADAM33 ST+4 2 allele and asthma in adults (OR = 0.863, 95% CI = 0.782–0.964, p = 0.008). However, no association was found between asthma and the ADAM33 F+1, S1, and V4 polymorphisms.Conclusions
This meta-analysis demonstrates that the ADAM33 S2 polymorphism confers susceptibility to asthma in Europeans and the ADAM33 ST+4 polymorphism is associated with asthma in Asians and adults. 相似文献16.
Rungusa Pantan Amnart Onsa-ard Jiraporn Tocharus Orawan Wonganan Apichart Suksamrarn Chainarong Tocharus 《Life sciences》2014
Aims
The aim of this study is to investigate the vasorelaxant effect of 16-O-acetyldihydroisosteviol (ADIS) and its underlying mechanisms in isolated rat aorta.Main methods
Rat aortic rings were isolated, suspended in organ baths containing Kreb's solution, maintained at 37 °C, and mounted on tungsten wire and continuously bubbled with a mixture of 95% O2 and 5% CO2 under a resting tension of 1 g. The vasorelaxant effects of ADIS were investigated by means of isometric tension recording experiment.Key findings
ADIS (0.1 μM–3 mM) induced relaxation of aortic rings pre-contracted by phenylephrine (PE, 10 μM) and KCl (80 mM) with intact-endothelium (Emax = 79.26 ± 3.74 and 79.88 ± 3.79, respectively) or denuded-endothelium (Emax = 88.05 ± 3.69 and 78.22 ± 6.86, respectively). In depolarization Ca2+-free solution, ADIS inhibits calcium chloride (CaCl2)-induced contraction in endothelium-denuded rings in a concentration-dependent manner. In addition, ADIS attenuates transient contractions in Ca2+-free medium containing EGTA (1 mM) induced by PE (10 μM) and caffeine (20 mM). By contrast, relaxation was not affected by tetraethylammonium (TEA, 5 mM), 4-aminopyridine (4-AP, 1 mM), glibenclamide (10 μM), barium chloride (BaCl2, 1 mM), and 1H-[1,2,3]oxadiazolo[4,3-α]quinoxalin-1-one (ODQ, 1 μM).Significance
These findings reveal the vasorelaxant effect of ADIS, through endothelium-independent pathway. It acts as a Ca2 + channel blocker through both intracellular and extracellular Ca2 + release. 相似文献17.
18.
Background
Trypanosoma brucei, responsible for African sleeping sickness, is a lethal parasite against which there is need for new drug protocols. It is therefore relevant to attack possible biomedical targets with specific preparations and since arginine kinase does not occur in humans but is present in the parasite it becomes a suitable target.Methods
Fluorescence quenching, thermodynamic analysis and FRET have shown that arginine kinase from T. brucei interacted with silver or gold nanoparticles.Results
The enzyme only had one binding site. At 25 °C the dissociation (Kd) and Stern–Volmer constants (KSV) were 15.2 nM, 0.058 nM− 1 [Ag]; and 43.5 nM, 0.052 nM− 1 [Au] and these decreased to 11.2 nM, 0.041 nM− 1 [Ag]; and 24.2 nM, 0.039 nM− 1 [Au] at 30 °C illustrating static quenching and the formation of a non-fluorescent fluorophore–nanoparticle complex. Silver nanoparticles bound to arginine kinase with greater affinity, enhanced fluorescence quenching and easier access to tryptophan molecules than gold. Negative ΔH and ΔG values implied that the interaction of both Ag and Au nanoparticles with arginine kinase was spontaneous with electrostatic forces. FRET confirmed that the nanoparticles were bound 2.11 nm [Ag] and 2.26 nm [Au] from a single surface tryptophan residue.Conclusions
The nanoparticles bind close to the arginine substrate through a cysteine residue that controls the electrophilic and nucleophilic characters of the substrate arginine–guanidinium group crucial for enzymatic phosphoryl transfer between ADP and ATP.General significance
The nanoparticles of silver and gold interact with arginine kinase from T. brucei and may prove to have far reaching consequences in clinical trials. 相似文献19.
Erdal Eren Tuba Edgunlu Huseyin Anil Korkmaz Esra Deniz Papatya Cakir Korcan Demir Esin Sakalli Cetin Sevim Karakas Celik 《Gene》2014