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Ellipse motion involving an angle about a vector is referred to as elliptical rotation. The purpose of this work is to define a new class of elliptic quaternions, elliptic inner product, and elliptic vector product, which we refer to as multiplicative elliptic quaternions. Then, utilizing those multiplicative elliptic quaternions, we produce a multiplicative elliptical rotation matrix and provide several applications. In the end, the theorems established were presented along geometric and physical applications suitable for the quaternionic structure with the help of Maple. There were also given examples of various applications. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ankara University Faculty of Medicine / Ankara Üniversitesi Tip Fakültesi Mecmuasi is the property of Galenos Yayinevi Tic. LTD. STI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, we define three types of 2‐ruled hypersurfaces in the Minkowski 4‐space 피14. We obtain Gaussian and mean curvatures of the 2‐ruled hypersurfaces of type‐1 and type‐2 and some characterizations about its minimality. We also deal with the first Laplace–Beltrami operators of these types of 2‐ruled hypersurfaces in 피14. Moreover, the importance of this paper is the definition of these surfaces by using the octonions in 피14. Thus, this is a new idea and makes the paper original. We give an example of 2‐ruled hypersurface constructed by octonion, and we visualize the projections of the images with MAPLE program. Furthermore, the optical fiber can be defined as a one‐dimensional object embedded in the four‐dimensional Minkowski space 피14. Thus, as a discussion, we investigate the geometric evolution of a linearly polarized light wave along an optical fiber by means of the 2‐ruled hypersurfaces in a four‐dimensional Minkowski space. [ABSTRACT FROM AUTHOR]

Objective: In this study, we investigated the effects of calreticulin (CALR) and JAK2V617F mutational status on clinical course and disease outcomes in Turkish patients with essential thrombocythemia (ET). Materials and Methods: Seventeen centers from Türkiye participated in the study and CALR- and JAK2V617F-mutated ET patients were evaluated retrospectively. Results: A total of 302 patients were included, of whom 203 (67.2%) and 99 (32.8%) were JAK2V617F- and CALR-positive, respectively. CALR-mutated patients were significantly younger (51 years vs. 57.5 years, p=0.03), with higher median platelet counts (987x109/L vs. 709x109/L, p<0.001) and lower median hemoglobin levels (13.1 g/dL vs. 14.1 g/dL, p<0.001) compared to JAK2V617F-mutated patients. Thromboembolic events (TEEs) occurred in 54 patients (17.9%), 77.8% of which were arterial. Compared to CALR mutation, JAK2V617F was associated with a higher risk of thrombosis (8.1% vs. 22.7%, p=0.002). Rates of transformation to myelofibrosis (MF) and leukemia were 4% and 0.7%, respectively, and these rates were comparable between JAK2V617F- and CALR-mutated cases. The estimated overall survival (OS) and MF-free survival of the entire cohort were 265.1 months and 235.7 months, respectively. OS and MF-free survival durations were similar between JAK2V617F- and CALR-mutated patients. Thrombosis-free survival (TFS) was superior in CALR-mutated patients compared to JAK2V617F-positive patients (5-year TFS: 90% vs. 71%, respectively; p=0.001). Age at diagnosis was an independent factor affecting the incidence of TEEs. Conclusion: In our ET cohort, CALR mutations resulted in higher platelet counts and lower hemoglobin levels than JAK2V617F and were associated with younger age at diagnosis. JAK2V617F was strongly associated with thrombosis and worse TFS. Hydroxyurea was the most preferred cytoreductive agent for patients with high thrombosis risk. [ABSTRACT FROM AUTHOR]

Introduction: Stimulation of liver regeneration after hepatectomy may provide important advantages, especially in cases where liver tissue is at a critical level. Some studies have reported that vascular endothelial growth factor (VEGF) might ameliorate liver regeneration in animals. In this study, we aimed to examine the effects of exogenous VEGF164 on the regeneration of liver tissue after a 70% hepatectomy in rats. Methods: Twenty Wistar Albino male rats, weighing 300-350 g, were randomly divided into four groups, each having five animals. Group 1 and Group 3 were designated as control groups, and Group 2 and Group 4 as experimental groups. All rats underwent laparotomy and 70% partial hepatectomy. Postoperatively, control groups were administered saline through the tail vein at 0 and 6 hours, and VEGF164 was administered to the experimental groups in the same manner at 0 and 6 hours. Blood samples were collected by sacrificing the rats at 24 hours for Group 1 and Group 2, and at 72 hours for Group 3 and Group 4. Subsequently, relaparotomy was performed and the remaining liver tissues were completely removed in all groups. Then, the resected liver tissues were used to determine morphological regeneration rates. The histopathological proliferation of the liver was evaluated by calculating the Ki-67 proliferative index. Results: In the histopathological evaluation, it was revealed that the liver proliferation index was significantly higher in the VEGF164 group at 72 hours (p=0.028). Although liver weights were higher in the experimental groups, no statistically significant results were obtained in terms of morphological liver regeneration rates (p>0.05). Discussion and Conclusion: Although the positive effects of exogenous VEGF on liver regeneration were not found in this rat model, statistically significant increases in the liver proliferation index are promising. [ABSTRACT FROM AUTHOR]

Background: Histopathological examination of appendectomy specimens may reveal malignancies. Based on these results, either appendectomy is sufficient or sometimes a further treatment protocol can be needed. In this study, malignancy-diagnosed cases on appendectomy specimen were examined. Methods: Patients who underwent appendectomy between January 2013 and December 2018 with a pre-diagnosis of acute appendicitis were evaluated retrospectively and those cases with malignancy were included in the study. Patients' age, sex, tumor type, tumor diameter, tumor grade, tumor localization, surgical margin, Ki-67 index, state of lymphovascular invasion, state of peri-neural invasion, and follow-up period duration were recorded. Results: On examination of 2336 appendectomy specimens, 16 patients (0.7%) were found to have neuroendocrine tumors (NET), 11 patients (0.5%) were found to have low-grade mucinous neoplasm (LAMN), and five patients (0.2%) were found to have primary appendix carcinomas. Appendix tumors usually present with acute appendicitis symptoms. Despite re-operation with right hemicolectomy (RHC) being required in the treatment of adenocarcinoma cases, appendectomy provides adequate treatment in most cases with NET and LAMN. With these tumors, which usually have a benign prognosis, it is important to perform the necessary screening in the postoperative period and not to interrupt follow-up. [ABSTRACT FROM AUTHOR]

Background/Aim: Intraductal papillomas (IDP) of the breast, though benign, share an association with the duct epithelium, similar to some breast malignancies. Percutaneous biopsies often fail to fully characterize these lesions. The decision to perform surgical excision for IDP of the breast is frequently based on the presence of atypia observed during percutaneous biopsy. However, consensus remains lacking regarding the management of IDP of the breast without atypia. This study was undertaken to share findings on IDP, contributing to a better understanding of their nature and guiding treatment approaches. Methods: We conducted a retrospective evaluation of data from 42 female patients diagnosed with intraductal papilloma through percutaneous biopsy, who subsequently underwent surgical excision between January 1, 2015, and August 25, 2023. Patients not diagnosed with intraductal papilloma, those with prior breast malignancy diagnoses, and those identified incidentally during other surgical procedures were excluded from the study. Data recorded included patient ages, the largest lesion diameters measured by ultrasonography, the percutaneous biopsy method (Fine needle aspiration biopsy [FNAB] or Core needle biopsy [CNB]), atypia status observed during percutaneous biopsy, histopathological features observed during surgical excision, and lesion diameter in cases where malignancy was upgraded. If ductal carcinoma in situ (DCIS) or invasive cancer was identified in the surgical excision specimen, it was classified as an upgrade. Results: The median age of the patients was 48.5 years (range: 12.9 years). FNAB was performed in ten cases (23.8%), while CNB was used in 32 cases (76.2%). There was no significant difference in the detection of atypia when comparing FNAB and CNB (P=0.57). Eight patients (19%) were diagnosed with atypical intraductal papilloma. Among them, three patients with atypia and two patients without atypia exhibited an upgrade to malignancy. The study revealed a malignancy upgrade rate of 37.5% for IDP with atypia and 5.9% for those without atypia. Furthermore, the average age of patients with malignancy upgrades was higher than that of patients with benign lesions (P=0.02). Conclusion: In light of the malignancies detected in cases of breast IDP, even in the absence of atypia, opting for surgical excision, particularly in older patients, can help prevent the oversight of these cancers. [ABSTRACT FROM AUTHOR]

Background/Aim: Pilonidal sinus (PS) is a benign chronic condition that primarily affects young people and can have a significant impact on their social life and work. Treatment options range from minimally invasive methods to surgical interventions involving wide excision. This study evaluates the outcomes of Kite excision, which aims to preserve healthy tissues, in cases of complicated PS extending along the natal cleft line. Methods: This retrospective cohort study included cases of complicated PS extending along the intergluteal sulcus. Patients with minimally extended PS, sinus openings extending laterally, or patients in whom the defect area was closed using other methods (e.g., rotation flap or Limberg flap) were excluded. Patient data were obtained from medical records and the hospital information system: patient age, gender, body mass index (BMI), length of hospital stay, duration of drainage, follow-up period, presence of flap necrosis or flap edema, wound dehiscence, and presence of seroma, hematoma, or surgical-site infections. Results: A total of 41 patients were included in the study; five (12%) were female. Twenty-three patients (56%) had recurrent PS; 18 patients (44%) underwent surgery for the first time. The mean age of the cohort was 28.5 years (standard deviation: 5.1 years). The mean BMI of the group was 30.2 kg/m² (standard deviation: 2.9 kg/m²), and the mean hospital stay was 1.3 days (standard deviation: 0.6 days). Wound dehiscence was observed in two patients (4.9%), and hematoma beneath the flap was observed in one patient (2.4%). Seroma was detected in one patient (2.4%). A surgical-site infection was identified in two patients (4.9%). The overall postoperative complication rate was 14.6%, and recurrence was observed in one patient (2.4%). Conclusion: Kite excision performed along the natal cleft line in cases of complicated PS is a safe, effective, and minimally invasive procedure that preserves healthy tissues. It is a recommended surgical treatment option in cases of complicated PS with vertical extension, and it will reduce the incidence of recurrence and increase patient comfort. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ankara University Faculty of Medicine / Ankara Üniversitesi Tip Fakültesi Mecmuasi is the property of Galenos Yayinevi Tic. LTD. STI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: Chronic kidney disease is common, irreversible, and associated with high mortality and morbidity. In this study, we aimed to investigate the effects of calcitriol and paricalcitol on chronic kidney disease progression in an adenine induced uremic rat model. Methods: Male Wistar-albino rats were fed a diet containing 0.75% adenine + 1.2% phosphorus for 3 weeks to induce chronic kidney disease. The rats were randomly divided into 6 groups: control group (n = 12), chronic kidney disease group (n = 12), chronic kidney disease+ calcitriol group (n = 12), chronic kidney disease +paricalcitol group (n = 12), calcitriol group (n = 6), paricalcitol group (n = 6). Animals were monitored for weight and systolic blood pressure. The kidney function parameters, parathyroid hormone, monocyte chemoattractant protein-1, and kidney histology were investigated. This research was supported by the Scientific Research Projects Unit (11-TIP-062). Results: Kidney histology proved that the adenine-induced uremic rat model was successfully established. Serum urea, creatinine, and phosphorus were significantly higher in chronic kidney disease, chronic kidney disease + calcitriol, chronic kidney disease +paricalcitol groups compared with the control group (P < .05). Calcitriol and paricalcitol provide effective parathyroid hormone suppression and decrease serum monocyte chemoattractant protein-1 levels in uremic rats. All uremic rats, including the paricalcitol and calcitriol treatment groups, lost weight. Paricalcitol significantly lowered systolic blood pressure in uremic rats (P = .006). Serum calcium was higher in calcitriol group compared with chronic kidney disease group. Paricalcitol caused less hyperphosphatemia in non-uremic rats than calcitriol. Conclusion: Paricalcitol and calcitriol therapy may prevent chronic kidney disease progression in uremic rats as they restore vitamin D metabolism during the disease. [ABSTRACT FROM AUTHOR]