Subtype Is a Predictive Factor of Nonsentinel Lymph Node Involvement in Sentinel Node-Positive Breast Cancer Patients

Kaptan Gülben,Uğur Berberoğlu,Ogün Aydoğan,Volkan Kınaş 한국유방암학회 2014 Journal of breast cancer Vol.17 No.4

Purpose: This study aimed to identify the effect of breast cancersubtype on nonsentinel lymph node (NSLN) metastasis in patientswith a positive sentinel lymph node (SLN). Methods: Therecords of 104 early breast cancer patients with a positive SLNbetween April 2009 and September 2013 were retrospectivelyevaluated. All patients underwent axillary lymph node dissection. The effects of the tumor subtype (luminal A, luminal/HER2+, humanepidermal growth factor receptor 2 [HER2] overexpression,and triple-negative) and other clinicopathological factors onNSLN metastasis were examined by univariate and multivariatestatistical analyses. Results: Fifty of 104 patients (48%) exhibitedNSLN metastasis. Univariate and multivariate analyses revealedthat tumor size and the ratio of positive SLNs were significantrisk factors of NSLN metastasis in patients with a positive SLN. The rate of NSLN metastasis was higher in patients with luminal/HER2+ and HER2 overexpression subtypes than that in patientswith other subtypes in the univariate analysis (p<0.001). In themultivariate analysis, both patients with luminal/HER2+(p<0.006) and patients with HER2 overexpression (p<0.031)subtypes had a higher risk of NSLN metastasis than patientswith the luminal A subtype. Conclusion: Subtype classificationshould be considered as an independent factor when evaluatingthe risk of NSLN metastasis in patients with a positive SLN. Thisresult supports the development of new nomograms includingbreast cancer subtype to increase predictive accuracy.

Numerical Analysis of the Non-Isothermal Viscoelastic Flow of Rotating Disc in a Cylindrical Enclosure Geometry

Yalın Kaptan,Ali Ecder,Kunt Atalık,Sang Ho Suh 대한기계학회 2010 대한기계학회 춘추학술대회 Vol.2010 No.11

The aim of this study is to generate a robust and efficient matrix-free Inexact Newton-Krylov solver (INGMRES) for the numerical investigation of non-isothermal viscoelastic flow. The rotating disc in a cylindrical enclosure (RDCE) is selected as the application problem since it is one of the basic geometries of the rheometry applications. The viscoelastic behavior of the fluid inside the container is modeled by adopting Upper Convected Maxwell (UCM), Oldroyd B and Giesekus constitutive relations; however only the results of the Giesekus are revealed. The effects of the flow elasticity, viscous dissipation and some material parameters are investigated. Newton type solvers are shown to be efficient for the differential viscoelastic constitutive models and overcome the difficulty of the high Weissenberg number problems. The results revealed that the viscous dissipation and temperature dependence of the viscosity should be modeled in order to obtain accurate results.

Rotating-surface-driven non-Newtonian flow in a cylindrical enclosure

Yalin Kaptan,Ali Ecder,Kunt Atalik 한국유변학회 2010 Korea-Australia rheology journal Vol.22 No.4

The numerical simulations of non-Newtonian flows become difficult as the Weissenberg number increases. The main objective of this study is to generate a robust and efficient matrix-free Inexact Newton-Krylov solver (IN-GMRES) which can deal with the high nonlinearities arising from the increased Weissenberg numbers. In order to achieve this aim, non-Newtonian flows of rotating surface driven cylindrical enclosure problem is numerically investigated by using three differential viscoelastic constitutive relations namely Upper Convected Maxwell (UCM), Oldroyd B and Giesekus. The results obtained by IN-GMRES solver are validated and compared with the POLYFLOW simulations. Additionally, the selection of the constitutive relation, effects of the Weissenberg number and effects of the Reynolds number are studied. The simulations indicate that the generated algorithm is capable of solving higher Weissenberg number problems (up to the Elasticity number limit of 130) when compared to the previous studies. Furthermore, it is shown that with the increasing Weissenberg number, the reversed flow can be observed in the flow domain and in some cases, depending on the Reynolds number, re-formation of the Newtonian like flow is possible at high Weissenberg numbers.

An Unappreciated Correlation : Surgical Treatment of Lumbosacral Disc Disease and Erectile Dysfunction

Kulaksizoglu, Haluk,Kaptan, Hulagu The Korean Neurosurgical Society 2010 Journal of Korean neurosurgical society Vol.47 No.4

Objective : The aim of the present study was to assess the effect of lumbar disc herniation surgery for low back pain on the erectile functioning. Methods : Thirty-eight patients, with age ranging from 22 to 56 years, who had presented with pain due to herniated lumbar discs were included in the study. International Index of Erectile Function (IIEF) Short Form questionnaire was used to evaluate the erectile functioning. Patient visits on the 1st week,1st month and 3rd month postoperatively were analyzed. Pain scores were also noted together with side effects and the complications of the surgery. Results : Of the 38 patients, 18 patients had reported erectile dysfunction; 10 patients mild and 8 patients moderate erectile dysfunction. Twenty patients did not report erectile problems. The herniation levels mostly were L5-S1 in 12 (31.6%). Overall, erectile dysfunction rates have improved in 31.7% of those previously with erectile dysfunction in a 3 month period after the surgery. Best results were obtained in those patients with mild erectile dysfunction preoperatively. Conclusion : Mild erectile dysfunction together with radiculopathy tends to improve after lumbosacral disc surgery. Moderate and severe erectile dysfunction may be related to a more severe nerve injury or to vascular and/or psychiatric factors. An evaluation of erectile functioning should routinely be performed in patients with lumbosacral disc disease both for data accumulation and for medico legal causes since the documentation of the correlation between erectile dysfunction and lumbosacral disc disease is still lacking.

심장 일의 측정을 위한 수학적 모델링

서상호(Sang-Ho Suh),Yalin Kaptan,노형운(Hyung-Woon Roh),송지운(Ji-Hoon Song) 대한기계학회 2011 대한기계학회 춘추학술대회 Vol.2011 No.4

심장 일을 계산하여 혈관질환을 진단하는 방법이 새롭게 대두되고 있다. 이 연구의 목적은 혈관내의 두 지점에서 압력을 측정하여 점도 모델로부터 압력 펄스 및 심장 일을 구하는 수학적 모델을 개발하는 것이다. 심장 일을 측정하기 위해서 커프로부터 구한 혈압과 펄스파에 대한 의료 데이터를 활용하였다. 심장 일은 Casson 및 Hershel-Bulkery 점도모델과 Windkessel 모델을 이용하여 구하였다. Evaluating the heart work is starting to emerge as a new diagnostic tool for arterial diseases. The aim of this study is to develop a mathematical model for the estimation of heart work by utilizing the pulse waves between two points of a vessel. In order to calculate heart work, medical data such as blood pressure waveforms which are measured by using a cuff are utilized. For this purpose, the modified Windkessel model is used with the viscosity models of Casson and Hershel-Bulkely.

심장 일의 측정을 위한 수학적 모델링

서상호(Sang-Ho Suh),Yalin Kaptan,노형운(Hyung-Woon Roh),송지운(Ji-Hoon Song) 대한기계학회 2012 大韓機械學會論文集B Vol.36 No.2

심장 일을 계산하여 혈관질환을 진단하는 방법이 새롭게 대두되고 있다. 이 연구의 목적은 혈관내의 두 지점에서 압력을 측정하여 점도 모델로부터 압력 펄스 및 심장 일을 구하는 수학적 모델을 개발하는 것이다. 심장 일을 측정하기 위해서 커프로부터 구한 혈압과 펄스파에 대한 의료 정보를 활용하였다. 본 연구의 목적은 혈관 내 두 측정점 사이의 펄스파를 이용하여 심장 일을 구하기 위한 수학적 모델의 개발이다. 심장 일은 Casson 및 Hershel-Bulkery 점도모델과 Windkessel 모델을 이용하여 구하였다. Casson 점도 모델과 Hershel-Bulkley 점도 모델을 이용하여 근위부에서의 컴플라이언스 값은 차이가 없으나 원위부에서 값은 큰 차이가 나타났다. Evaluation of the heart work is starting to emerge as a new diagnostic tool for arterial diseases. The aim of this study is to develop a mathematical model for the estimation of heart work utilizing the pulse waves between two points of a vessel. In order to calculate heart work, medical data such as blood pressure waveforms (which are measured using a cuff) are utilized. The heart work is calculated by employing the modified Windkessel model together with the viscosity models of Casson or Herschel-Bulkely (H-B). The results indicate that the compliance values at the proximal and distal locations differ for the Casson and H-B models.

The Effect of Terpenes on Percutaneous Absorption of Tiaprofenic Acid Gel

Alper Okyar,Maksat Nuriyev,Ayca Yildiz,Zeliha Pala-Kara,Narin Ozturk,Engin Kaptan 대한약학회 2010 Archives of Pharmacal Research Vol.33 No.11

Tiaprofenic acid is a potent analgesic and nonsteroidal anti-inflammatory drug (NSAID) and like any other nonsteroidal anti-inflammatory drug, oral administration of the conventional dosage forms of tiaprofenic acid invariably causes gastrointestinal side effects. In an effort to eliminate these side effects while enhancing the drug concentration at the target tissue, an epidermal application of tiaprofenic acid seems to be an effective alternative drug delivery modality. This study attempts to demonstrate the influence of different terpenes (d-limonene, menthol and nerolidol) in various combinations of preparations on the percutaneous penetration of tiaprofenic acid from Carbopol® 940 based gel formulations (1%) in an ex vivo experiment using Franz-type diffusion cells. The enhancement effect of terpenes on skin absorption of tiaprofenic acid was further evaluated by an in vivo method in rats. Amongst the terpenes used, d-limonene was the most outstanding penetration enhancer that was reference to penetration of tiaprofenic acid through rat skin ex vivo. In vivo penetration study shows that the AUC0-48h was increased by about 10 fold by the addition of 5% d-limonene to the formulation. Histological studies show that d-limonene causes disruption on the skin surface and is responsible for enhanced penetration of tiaprofenic acid. Since tiaprofenic acid is known to cause gastrointestinal disturbances following systemic administration, topical formulations of tiaprofenic acid in gel form including 5% d-limonene could be suggested as an alternative.

심장일에 대한 P-V 선도 연구

서상호(Sang-Ho Suh),김형호(Hyoung-Ho Kim),노형운(Hyung-Woon Roh),Yalin kaptan 대한기계학회 2011 대한기계학회 춘추학술대회 Vol.2011 No.10