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A time-varying sliding-coefficient-based decoupled terminal sliding mode control strategy is presented for a class of fourth-order systems. First, the fourth-order system is decoupled into two second-order subsystems. The sliding surface of each subsystem was designed by utilizing time-varying coefficients. Then, the control target of one subsystem to another subsystem was embedded. Thereafter, a terminal sliding mode control method was utilized to make both subsystems converge to their equilibrium points in finite time. The simulation results on the inverted pendulum system demonstrate that the proposed method exhibits a considerable improvement in terms of a faster dynamic response and lower IAE and ITAE values as compared with the existing decoupled control methods., (Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.)

Objective: This study aimed to investigate the role of vascular endothelial growth factor (VEGF) and its receptors (VEGFR1, VEGFR2) in maternal and embryonic tissues in the etiology of early pregnancy loss., Methods: Immunohistochemistry was used to analyze the expression of VEGF and its receptors in placental and decidual tissues of 80 women with spontaneous incomplete abortion (n = 20), missed abortion (n = 20), blighted ovum (n = 20) and from early terminated pregnancies (n = 20)., Results: Compared with the controls, all study groups showed weaker VEGF immunoreactivity in cytotrophoblasts and syncytiotrophoblasts of placental villi and endothelial cells of decidua (p = 0.002, p = 0.003, p < 0.001 respectively). Decidual endothelial cells of study groups except for blighted ovum showed weaker VEGFR1 immunoreactivity as compared to controls (p < 0.001). Placental villi cytotrophoblasts, syncytiotrophoblasts, decidual endothelial cells and endometrial gland epithelial cells showed weaker VEGFR2 immunoreactivity in all study groups compared to controls (p < 0.001). Placental villi endothelial cells showed the weakest VEGFR2 immunoreactivity in incomplete abortion group and the strongest staining in the blighted ovum group (p < 0.001)., Conclusion: These results suggest that decreased expression of VEGFR1 in decidua and weaker VEGF and VEGFR2 expression in placental villi and decidua may be associated with early pregnancy loss.

Aim: To determine utility of the frozen section (FS) in the operative management of endometrial pre-malignant lesions., Materials and Methods: We retrospectively analyzed patients who underwent abdominal hysterectomy with preoperative diagnosis of complex atypical endometrial hyperplasia (CAEH) and simple endometrial hyperplasia (SEH) between May 2007 and December 2013. Frozen and paraffin section (PS) results were compared. Sensitivity, specificity, the positive predictive value (PPV), the negative predictive value (NPV) and the accuracy in predicting EC on FS were evaluated with 95% confidence intervals (CIs) for each parameter. The correlation between FS and PS was calculated as an κ coefficient., Results: Among 143 preoperatively diagnosed CAEH cases, 60 (42%) were malignant and 83 (58%) were benign in PS; and among 60 malignant cases diagnosed in PS, 43 (71%) were "malignant" in FS. Sensitivity, specificity, PPV and NPV for FS were 76%, 100%, 100% and 87.5%, respectively., Conclusions: We found that FS is reliable and applicable in the management of endometrial hyperplasias. It is important that the pathologist should be experienced because FS for endometrial pre-malignant lesions has significant inter-observer variability. The other conclusion is that patients with the diagnosis of EH, especially those who are postmenopausal, should undergo surgery where FS investigation is available.

Unlabelled: BACKGROUNDŕ: Hyperreactio luteinalis is a rare condition that stems from theca cell hyperplasia in the ovaries due to a high level of human chorionic gonadotropin during gestation. It occurs commonly in pregnant patients with trophoblastic disease, occasionally in multiple pregnancies, and rarely in normal singleton pregnancy., Case Report: A 24-year-old pregnant woman, G3 P0, who was admitted to the Perinatology Clinic with increasing findings of virilization during pregnancy was presented. The patient had bilaterally enlarged multicystic ovaries on sonographic examination and elevated serum androgen levels She was managed conservatively until 38th week of gestation as a presumptive diagnosis of hyperreactio luteinalis. Elevated blood pressure and prominent proteinuria were detected during the follow-up of the patient and labor was induced. She underwent an emergency caesarean delivery because of fetal distress. During caesarean section, ovarian biopsies were taken and a histopathological diagnosis of hyperreactio luteinalis was determined. The female fetus also presented virilization., Conclusion: Although infrequent, hyperreactio luteinalis with both maternal and fetal virilization can occur in women with spontaneous singleton pregnancies. The clinical manifestations in such women may be complicated by severe preeclampsia.

Gonadoblastoma is a rare gonadal tumor with tumor cells arranged in nests surrounded by ovarian stroma containing Leydig or lutein-type cells. In 50% of the cases, there is an overgrowth of germ cells with progression to dysgerminoma. A case of gonadoblastoma with coexisting dysgerminoma developing in both ovaries of a 20-year-old girl who had increased abdominal girth is presented here. A pelvic mass measuring 20 x 14 cm was detected by pelvic ultrasonography. Bilateral salphingo-oophorectomy was performed. The histopathological report revealed bilateral gonadoblastoma with coexisting dysgerminoma. After surgery the patient received radiation and chemotherapy (BEP: bleomycin, etoposide, cisplatin) and was started on hormone replacement therapy. Five years and eight months after treatment, the patient is well and free of recurrence.

Objective: Malignant melanoma, which has a highly malignant potential, is a tumor of the skin and mucosal membranes. Malignant melanomas of the female genital tract, including the vulva and vagina, are rare. Their overall prognosis is poor and is worse than that for cutaneous melanomas., Case Reports: Clinical data for five patients with primary malignant melanoma are presented. Diagnosis was based on histologic and immunohistochemical examinations. Case 1 was a 58-year-old woman with mucosal lentiginous melanoma of the vulva. The other four patients, all of whom were over 40 years old, had vaginal melanomas. They were all treated with surgery, and three also received postoperative adjuvant therapy with interferon alpha-2b. Despite this, three of the patients died owing to widespread disease., Conclusion: Although malignant melanoma of the female genital tract is uncommon, elderly women should undergo regular gynecologic examinations and suspicious pigmented lesions should be biopsied. The use of immunohistochemical assays could markedly improve diagnosis. However, the prognosis for these tumors is poor, regardless of the treatment delivered, and they are associated with a high rate of recurrence and low long-term survival. Surgery is the best available treatment for controlling and potentially curing malignant melanomas.

Inhibin is a heterodimeric protein hormone that appears to be a sensitive immunohistochemical marker of sex cord-stromal tumors. Although sex cord-stromal tumors can usually be distinguished from ovarian epithelial tumors or their metastases by morphology or by using antibodies against intermediate filaments, the diagnosis remains difficult in rare situations in such cases as sarcomatoid granulosa-theca cell tumors, ovarian small cell carcinomas, or soft-tissue sarcomas. The purposes of this study were to examine inhibin alpha and beta immunoreactivity in a wide range of gonadal stromal neoplasms and to assess its value in the differential diagnosis of problematic tumors. A total of 108 paraffin-embedded ovarian and extraovarian tumors were examined immunohistochemically by using anti-alpha inhibin and anti-beta inhibin. Inhibin alpha immunostaining was identified in 46 (81%) of 57 gonadal stromal tumors, one (14%) of seven endometrial stromal tumors, and one (50%) of two primary ovarian carcinoid tumors. Inhibin beta immunostaining was detected in 55 (96%) of 57 gonadal stromal tumors, two (29%) of seven endometrial stromal tumors, one (50%) of two dysgerminomas, and in all of two (100%) primary ovarian carcinoid tumors. Inhibin alpha expression was not detected in any ovarian surface epithelial tumor cells. Some surface epithelial tumors showed stromal inhibin alpha (15% of cases) and inhibin beta (48% of cases) positivity. Weak immunoreactivity for inhibin beta was found in most (83% of cases) ovarian surface epithelial tumors. Two ovarian Burkitt lymphomas were negative for inhibin alpha and beta. Inhibin alpha is a sensitive immunohistochemical marker of gonadal stromal tumors and is of value in the differential diagnosis of ovarian neoplasia. Inhibin beta is a nonspecific marker for ovarian neoplasms, showing expression on tumor and stromal cells of different epithelial or stromal tumors.

Unlabelled: Some primary carcinomas of the breast have been classified as neuroendocrine. In this paper we report on 12 cases of neuroendocrine carcinoma of the breast displaying common and uncommon histological features., Materials and Methods: All patients were aged from 43 to 79 (median 66.5) years. The tumors were unilateral and ranged from 0.8 to 7 cm (median 2.35 cm) in diameter. Four tumors were classified as solid cohesive, two as solid papillary, one as Merkel cell-like, two as cellular mucinous, two as cellular mucinous with micropapillary features and one as cellular mucinous with prominent signet ring cells. The tissues were fixed in formalin and routinely processed. All materials were stained with PAS, Alcian blue and also hematoxylin and eosin. Immunohistochemical examination was carried out by the avidin-biotin method using the following antibodies: estrogen receptor protein, progesterone receptor protein, p53, cerbB-2, Ki67, neuron-specific enolase, chromogranin, and synaptophysin., Results: In all cases the tumor cells were stained positively with NSE. Synaptophysin and chromogranin positivity was detected in 11 and five cases, respectively. The prominent histological features were: extensive intraductal growth, pseudorosettes and palisades, low-grade cytologic atypia, plasmacytoid appearance of the tumor cells, and intracellular and extracellular mucin., Conclusion: Neuroendocrine-differentiated carcinoma of the breast is a rare and distinct category with different histological subtypes.

Invasive micropapillary carcinoma of the breast is an uncommon variant of infiltrating ductal carcinoma. Observing its distinctive cytologic appearance and aggressive behavior is important for early diagnosis by fine-needle aspiration cytology (FNAC). There are only a few reported cases in the literature. Five women presented with breast masses. FNAC showed malignant epithelial tumors, and mastectomy materials showed invasive micropapillary carcinoma for all of them. Three patients had axillary lymph node metastases. Invasive micropapillary carcinoma, with its angulated papillary clusters lacking a fibrovascular core, and irregular crowded nuclei, has a distinctive cytologic appearance which correlates with its histological features. A differential diagnosis from other primary or metastatic papillary lesions of the breast may be possible using immunohistochemistry and some cytologic features. The limited experience with invasive micropapillary carcinoma should not discourage others from undertaking further studies., (Copyright 2002 Wiley-Liss, Inc.)

Trimetazidine (TMZ), a potent antioxidant agent, has been used to protect the myocardium, liver and kidney from ischemia reperfusion (IR) injury. We investigated the effect of TMZ, a cellular anti-ischemic agent and a free radical scavenger, on 60 min of warm intestinal IR injury in rats. Sprague-Dawley rats were divided into three groups: a sham-operated group (no IR injury, n = 8), an ischemic control group (control, n = 8), and a TMZ-treated group (3 mg/kg, n = 8). Malondialdehyde (MDA) levels, myeloperoxidase (MPO) activity, and mucosal damage were investigated after 120 min of reperfusion. MDA levels and MPO activity were more elevated and histopathological damage more severe in the control group than in the sham group (P < 0.05). MDA levels and MPO activity were lower and there was less histopathological damage in the TMZ group than in the control group (P < 0.05). Accumulation of lipid peroxidation products and neutrophils in mucosal tissues were significantly inhibited by TMZ treatment. We conclude that pretreatment of rats with TMZ before intestinal ischemia attenuates but does not prevent, histological damage.