Barbed sutures versus conventional tenorrhaphy in flexor tendon repair: An ex vivo biomechanical analysis

Colak, Ozlem,Kankaya, Yuksel,Sungur, Nezih,Ozer, Kadri,Gursoy, Koray,Serbetci, Kemal,Kocer, Ugur Korean Society of Plastic and Reconstructive Surge 2019 Archives of Plastic Surgery Vol.46 No.3

Background The management of flexor tendon injuries has evolved in recent years through industrial improvements in suture materials, refinements of repair methods, and early rehabilitation protocols. However, there is no consensus on the ideal suture material and technique. This study was conducted to compare the tensile strength, repair time, and characteristics of 4-strand cruciate, modified Kessler, and 4-strand horizontal intrafiber barbed sutures for flexor tenorrhaphy with a 12-mm suture purchase length in an animal model. Methods The right third deep flexors of 60 adult Leghorn chicken feet were isolated and repaired with a 12-mm suture purchase length. The tendons were randomly assigned to three groups of equal number (n=20 each). Groups 1 and 2 received 4-strand cruciate and modified Kessler repair with conventional suture materials, respectively. A 4-strand horizontal intrafiber barbed suture technique was used in group 3. The repaired tendons were biomechanically tested for tensile strength, 2-mm gap resistance, and mode of failure. Repair times were also recorded. Results The maximum tensile strength until failure was $44.6{\pm}4.3N$ in group 1, $35.7{\pm}5.2N$ in group 2, and $56.7{\pm}17.3N$ in group 3. The barbed sutures were superior to the other sutures in terms of the load needed for 2-mm gap formation (P<0.05). Furthermore, the barbed sutures showed the shortest repair time (P<0.05). Conclusions This study found that 4-strand horizontal intrafiber barbed suture repair with a 12-mm purchase length in a chicken flexor tendon injury model showed promising biomechanical properties and took less time to perform than other options.

Morphine: Patient Knowledge and Attitudes in the Central Anatolia Part of Turkey

Colak, Dilsen,Oguz, Arzu,Yazilitas, Dogan,Imamoglu, Inanc Goksen,Altinbas, Mustafa Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.12

Background: In Muslim majority countries (MMC) opioid use for pain management is extremely low. The underlying factors contributing to this are not well defined. Aim: The aim of this study was to survey the attitudes of cancer patients towards morphine use for pain management in a MMC and identify the factors that influence patient decisions to accept or refuse morphine as treatment for cancer pain. Settings/participants: Patients were questioned whether they had pain or not, the severity and the medications for pain management. Questions included what type of medication they thought morphine was, whether or not they would be willing to take morphine if recommended for pain management and the basis for their decision if they were against morphine use. Results: Four hundred and eighty-eight patients participated in the study. Some 50% of the patients who refused morphine use and 36.8% of the patients who would prefer another drug, if possible, identified fear of addiction as the basis for their decision. Reservation of morphine for later in their disease was the case for 22.4% of the patients who refused morphine use. Only 13.7 % of the patients refusing morphine and 9.7% of the patients who preferred another drug, if possible, cited religious reasons as the basis for this decision. Conclusions: Identifying the underlying factors contributing to low opioid use for pain management in MMC is important. Once the underlying factors were identified, all efforts should be taken to overcome them as they are barriers to improving patient pain management.

Parallel DC-AC Conversion System Based on Separate Solar Farms with MPPT Control

Ilhami Colak,Ersan Kabalci,Gungor BAL 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

Three separate solar farms that provide 15 ㎾ power for each farm are modelled using Matlab Simulink real-time analysis software in this study. Each solar farm models are constituted by connecting 170W photovoltaic (PV) panels and energy conversion is performed with maximum power point tracking (MPPT) algorithms in each converter. The MPPT algorithm utilized in the control step of converters is developed using Perturb and Observe (P&O) structure. The converters used in the solar farms are designed in boost converter topology while output voltages are collected in DC busbar with parallel connection of converters. The converters are connected to busbar over interphase transformers (IPT). The DC busbar voltage is applied to a full bridge inverter to generate 3-phase AC voltages at the output of inverter. The three-phase inverter is controlled with sinusoidal pulse width modulation (SPWM) scheme, which is developed with phase shifted carrier signals. The load of inverter is set to an adjustable load, which is capable to be increased up to 50 ㎾. The measurement points seen in the Simulink design are analysed in detail. Each measurement point’s definition and screen captures are also evaluated in the study.

Impaired Gallbladder Motility and Increased Gallbladder Wall Thickness in Patients with Nonalcoholic Fatty Liver Disease

( Yasar Colak ),( Gulcin Bozbey ),( Tolga Erim ),( Ozge Telci Caklili ),( Celal Ulasoglu ),( Ebubekir Senates ),( Hasan Huseyin Mutlu ),( Banu Mesci ),( Mehmet Sait Dogan ),( Guralp Tasan ),( Feruze Y 대한소화기기능성질환·운동학회(구 대한소화관운동학회) 2016 Journal of Neurogastroenterology and Motility (JNM Vol.22 No.3

Background/Aims Nonalcoholic fatty liver disease (NAFLD) is currently the most common chronic liver disease worldwide. Along with the increase in the incidence of NAFLD and associated obesity, an increase in gallbladder disease (GD) has been noted. This has led to the identification of a new disease entity called fatty GD. There is a gap in the literature on the dynamics of gallbladder function in patients with NAFLD. Methods An observational case-control study, a total of 50 patients with biopsy proven NAFLD without gallbladder stone/sludge and 38 healthy comparison subjects were enrolled. Fasting, postprandial gallbladder volumes (PGV), gallbladder ejection fraction (GEF), and fasting gallbladder wall thickness (FGWT) were measured by real-time 2-dimensional ultrasonography. Results Fasting gallbladder wall thickness, fasting gallbladder volumes and PGV were significantly higher in patients with NAFLD than control subjects (P < 0.001, P = 0.006, and P < 0.001, respectively). Gallbladder ejection fraction was significantly lower in the NAFLD group than the controls (P = 0.008). The presence of NAFLD was an independent predictor for GEF, PGV, and FGWT. Also, steatosis grade was an independent predictor for GEF, and GEF was significantly lower in the nonalcoholic steatohepatitis (NASH) subgroup than the controls. Conclusions Gallbladder dysfunction and increase in gallbladder wall thickness exists in asymptomatic (without stone/sludge and related symptoms) patients with NAFLD and are useful in identifying fatty GD. Measurement of these variables in NAFLD patients may be useful in identifying those at higher risk for GD. (J Neurogastroenterol Motil 2016;22:470-476)

A Novel Intelligent Decision Support Tool for Average Wind Speed Clustering

I. Colak,E. Kabalci,M. Yesilbudak,H.T. Kahraman 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

The utilization ratio of wind energy, which is one of the renewable energy sources, is increased around 25% since last 15 years. However, the parameters such as performance of wind turbines and climate features are not analyzed adequately. At the analysis stage of these parameters, data mining techniques are required to be used. In this study, the agglomerative hierarchical clustering method which is one of the data mining techniques is used to analyze the provinces located in the Central Anatolia Region of Turkey in terms of average wind speed. Nearest neighbor algorithm is used as the clustering algorithm. Euclidean, Manhattan and Minkowski distance metrics are used determine the optimum hierarchical clustering results in this algorithm. The achieved clustering results based on Euclidean distance metric provide the optimum inferences to expert according to other distance metrics.

Is placental KISS-1 expression associated with first trimester abortion spontaneous?

( Eser Colak ),( Emel Ebru Ozcimen ),( Ozgur Hilal Erinanç ),( Yusuf Aytac Tohma ),( Mehmet Ufuk Ceran ) 대한산부인과학회 2020 Obstetrics & Gynecology Science Vol.63 No.4

Objective Several studies have examined biological markers during the first trimester to predict the maintenance of a healthy pregnancy. One such marker is kisspeptin, which is encoded by the KISS-1 gene. We aimed to determine whether firsttrimester pregnancy losses were associated with levels of placental KISS-1 expression. Methods This prospective case control study was conducted at a tertiary center. The study group included 27 and 24 patients who underwent dilation and curettage at <10 weeks of gestation, due to first trimester spontaneous pregnancy loss and for elective termination (control), respectively. Placental and decidual tissues from all patients were sectioned and immunohistochemically analyzed for kisspeptin. Results Age, gravida status, parity number, gestational week, and number of previous abortions did not significantly differ between the groups. KISS-1 expression levels were significantly lower in the group with spontaneous abortion compared with the group with elective termination. The median staining intensity of KISS-1 expression in the elective and spontaneous termination groups were 3 (strong) and 2 (moderate), respectively (P=0.004). KISS-1 expression levels were significantly lower among patients with previous abortions in the elective termination group (P=0.002). Conclusion KISS-1 expression levels were found to be significantly reduced in patients with spontaneous pregnancy loss; KISS-1 plays an important role in the implantation and continuation of pregnancy.

Heavy metal resistances and biosorptive behaviors of Paenibacillus polymyxa: Batch and column studies

Ferdag Colak,Asim Olgun,Necip Atar,Demet Yazıcıoglu 한국공업화학회 2013 Journal of Industrial and Engineering Chemistry Vol.19 No.3

Continuous fixed-bed column and batch biosorption studies were conducted to examine the effectiveness of Paenibacillus polymyxa as an adsorbent for the removal of copper and nickel from aqueous solutions. Experimental data obtained has been fitted well with Langmuir isotherm model and also exhibited very high correlation coefficients which confirmed suitability of the model and biosorption process. Differences among batch and continuous isotherms were observed; the maximum uptake capacity of Cu(II) and Ni(II) in batch system was about 49.8 (mg/g) and 35.02 (mg/g), respectively. Furthermore, the effects of heavy metals on micro-organism growth were studied.

Posttreatment Effects of Olea Europaea L. Leaf Extract on Carbon Tetrachloride-Induced Liver Injury and Oxidative Stress in Rats

Derya Ustuner,Emine Colak,Murat Dincer,Neslihan Tekin,Dilek Burukoglu Donmez,Fahrettin Akyuz,Ertugrul Colak,Umut Kerem Kolac,Emre Entok,Mehmet Cengiz Ustuner 한국식품영양과학회 2018 Journal of medicinal food Vol.21 No.9

The aim of this study is to examine the therapeutic effects of Olea europaea L. leaf extract on carbon tetrachloride (CCl4)-induced liver damage in rats. In the experiments, 3- to 4-month-old 28 male Sprague–Dawley rats were divided into four groups: control, O. europaea leaf extract, CCl4, and curative. The CCl4 and curative groups received CCl4 (0.2 mL/kg) intraperitoneally for 10 days to form hepatic injury. O. europaea (80 mg/kg) leaf extract was given orally to the curative group dissolved in distilled water the following 14 days. Hepatic and antioxidant enzyme levels, p53, caspase 3, lipid peroxidation marker malondialdehyde (MDA), and also DNA fragmentation levels were determined to establish oxidative stress in hepatic cell damage and its consequences. After formation of liver damage, oral administration of the O. europaea significantly reduced CCl4-induced elevations of serum alkaline phosphatase, aspartate aminotransferase and alanine aminotransferase levels (P < .001), MDA levels of both blood (P < .001) and liver tissues (P < .001), DNA fragmentation (P < .001), p53 (P < .001), and caspase 3 (P < .001) levels of liver tissues. Also this administration in curative group significantly increased CCl4-induced reductions of superoxide dismutase (SOD) (P < .001) and catalase (CAT) (P < .001) activity of blood samples and decreased SOD (P < .001) and CAT (P < .05) activity observed in liver tissue curative groups compared with CCl4 curative group. In CCl4 group, liver tissue samples exhibited remarkable damage because of CCl4 and reduction of these damages were observed in the curative group. Our results showed that O. europaea leaf extract was effective in reducing hepatic damage caused by CCl4 by reducing lipid peroxidation, regulating antioxidant enzymes, and minimizing DNA damage.

Prognostic Value of Osteopontin in Patients Treated with Primary Radiotherapy for Head and Neck Cancer

Etiz, Durmus,Ataizi, Fulya Colak,Bayman, Evrim,Akcay, Melek,Acikalin, Mustafa Fuat,Colak, Ertugrul,Ciftci, Evrim Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.9

Background: The prognostic value of tumor osteopontin (OPN) in patients with squamous-cell head and neck cancer (SCHNC) was investigated. Materials and Methods: OPN expression was assessed by immunohistochemical methods in 50 patients, who were treated with primary radiotherapy (RT) for locally advanced SCHNC. The effects of OPN on clinical parameters, local-regional control after RT and metastasis-free survival, was assessed. Results: The rate of OPN expression in tumor tissue was 76%. OPN positive cases had lower Hb levels (p=0.088). Mean time to local recurrence was 53.8 months (SE 3.9) in OPN-negative cases and 39.1 months (SE 4.7) in OPN-positive cases (p=0.047). OPN increased the risk of local recurrence 5.9 times (p=0.085). It had no effect on metastasis-free (p=0.116) or overall survival (p=0.123). OPN was positive in 12 of 19 cases that developed grade 3-4 acute radiation dermatitis (p=0.096). Conclusions: OPN expression is associated with an increase in local recurrence in patients who were treated with primary RT for locally advanced SCHNC.

Determination and Characterization of Thermostable Esterolytic Activity from a Novel Thermophilic Bacterium Anoxybacillus gonensis A4

Faiz, Ozlem,Colak, Ahmet,Saglam, Nagihan,Canakci, Sabriye,Belduz, Ali Osman Korean Society for Biochemistry and Molecular Biol 2007 Journal of biochemistry and molecular biology Vol.40 No.4

A novel hot spring thermophile, Anoxybacillus gonensis A4 (A. gonensis A4) was investigated in terms of capability of tributyrin degradation and characterization of its thermostable esterase activity by the hydrolysis of p-nitrophenyl butyrate (PNPB). It was observed that A. gonensis A4 has an esterase with a molecular weight of 62 kDa. The extracellular crude preparation was characterized in terms of substrate specificity, pH and temperature optima and stability, kinetic parameters and inhibition/activation behaviour towards some chemicals and metal ions. Tributyrin agar assay showed that A. gonensis A4 secreted an esterase and $V_{max}$ and $K_m$ values of its activity were found to be 800 U/L and 176.5 ${\mu}M$, respectively in the presence of PNPB substrate. The optimum temperature and pH, for A. gonensis A4 esterase was $60-80^{\circ}C$ and 5.5, respectively. Although the enzyme activity was not significantly changed by incubating crude extract solution at $30-70^{\circ}C$ for 1 h, the enzyme activity was fully lost at $80^{\circ}C$ for same incubation period. The pH-stability profile showed that original crude esterase activity increased nearly 2-fold at pH 6.0. The effect of some chemicals on crude esterase activity indicated that A. gonensis A4 produce an esterase having serine residue in active site and -SH groups were essential for its activity.