Densification effect on field emission characteristics of CNT film emitters for electron emission devices.

Field electron emission characteristics of the carbon nanotube (CNT) film emitters were investigated according to densification conditions such as nitric acid, acetic acid, and salicylic acid. The emission performance of the CNT film emitters was strongly affected by the densification conditions. Salicylic acid exhibits the best field electron emission properties of the CNT film emitters, followed by nitric acid and acetic acid. The efficient densification of the CNT film emitter by salicylic acid is caused by the role of polarity and p orbitals, nitric acid by hydrogen ions, and acetic acid by weak polarity. After the densification with salicylic acid, the turn-on field of the CNT film emitter decreases from 1.94 Vµm-1to 1.86 Vµm-1, the threshold field decreases from 3.41 Vµm-1to 2.95 Vµm-1, the emission current significantly increases from 20.92 mA to 43.98 mA, and the degradation rate from the long-term emission stability decreases from 49.9% to 21%. The improved emission characteristics are attributed to the increased emission sites at the CNT film and the increased electrical conductivity of the CNT film. The densification is a useful way to enhance the field electron emission properties of CNT film emitters.

Paeonia lactiflora improves ovarian function and oocyte quality in aged female mice.

Although ovarian aging is a key cause of decreased ovarian function and oocyte quality, it remains a problem in infertility treatment. Therefore, this study is aimed to investigate whether Paeonia lactiflora (PL), a herb improves ovarian function and oocyte quality using aged female mice. C57BL/6 female mice aged 8 months were treated orally every day with PL of 26.5 mg/kg (n=7) and 53 mg/kg (n=7) of body weight for 4 weeks using an oral zoned needle. The control group (n=7) was treated with normal saline. Ovaries and serum were collected for the H&E stain and the evaluation of reactive oxygen species (ROS) levels, respectively. In the second experiment, female mice were orally administered with PL (26.5 mg/kg: n=12, 53 mg/kg: n=12, control: n=12) and then superovulated with PMSG and hCG, and mated with male mice. Zygotes were retrieved and cultured for 4 days. Ovaries were provided for examination of expressions of genes associated with angiogenesis (VEGF and visfatin), anti-aging (Sirt1 and Sirt2), and follicular development (c-Kit, BMP-15, and GDF-9). PL significantly increased numbers of surviving follicles (primordial, primary, secondary, and antral), numbers of zygotes retrieved, embryo development rate, and ovarian expression of VEGF, visfatin, c-Kit, BMP-15, and GDF-9 at both doses. However, ovarian expression of Sirt1 and Sirt2 was increased at 53.0 mg/kg of PL. ROS levels were not affected by PL. These results suggest that PL may possess beneficial effects regarding ovarian function and oocyte quality, possibly by activation of ovarian angiogenesis and follicular development.

Role of Visfatin in Restoration of Ovarian Aging and Fertility in the Mouse Aged 18 Months.

The activation of dormant primordial follicles and ovarian angiogenesis has been attempted as a new treatment strategy for age-related ovarian aging. This study examined whether visfatin rescues age-related fertility decline in female mice aged 18 months, and whether this effect relates to the mTOR/PI3K signaling pathways for activation of primordial follicles and ovarian angiogenesis. Female mice were intraperitoneally injected with 0.1 ml of 500 ng/ml or 1000 ng/ml of visfatin three times at intervals of 2 days, and both ovaries were provided for H&E staining. In another experiment, the mice were superovulated with pregnant mare's serum gonadotropin and human chorionic gonadotropin, and were mated with males. After 18 h, zygotes were collected and cultured for 4 days, and numbers and embryo developmental competency of zygotes retrieved were evaluated. The expression of mTOR/PI3K signaling pathway regulated genes (4EBP1, S6K1, and RPS6) and angiogenic factors (VEGF, visfatin, and SDF-1α) in the ovary were examined. As well, visfatin-treated mice were mated with male mice for 2 weeks, and the pregnancy outcome was monitored up to 3 weeks. Visfatin significantly increased the total numbers of follicles compared with control. Numbers of zygotes retrieved, blastocyst formation rate, and pregnancy rate were significantly increased at 500 ng/ml of visfatin (2.83%, 40.0%, and 80%, respectively) compared with control (0, 0, and no pregnancy). Ovarian expressions of S6K1, RPS6, VEGF, visfatin, and SDF-1α were significantly stimulated at 500 ng/ml of visfatin. These results show that visfatin treatment of an optimal dose rescues age-related decline in fertility, possibly by stimulating mTOR/PI3K signaling.

Establishment of Effective Mouse Model of Premature Ovarian Failure Considering Treatment Duration of Anticancer Drugs and Natural Recovery Time.

OBJECTIVES: This study was aimed to establish the most effective premature ovarian failure (POF) mouse model using Cyclophosphamide (CTX), busulfan (Bu), and cisplatin considering treatment duration of anticancer drugs and natural recovery time. METHODS: POF was induced by intraperitoneally injecting CTX (120 mg/kg)/Bu (12 mg/kg) for 1 to 4 weeks or cisplatin (2 mg/kg) for 3 to 14 days to C57BL/6 female mice aged 6 to 8 weeks. Controls were injected with equal volume of saline for the same periods. Body weight was measured every week, and ovarian and uterine weights were measured after the last injection of anticancer drug. To assess ovarian function, POF-induced mice were superovulated with pregnant mare serum gonadotropin and human chorionic gonadotropin, and then mated with male. After 18 hours, zygotes were retrieved and cultured for 4 days. Finally, the mice were left untreated for a period of times after the final injection of anticancer drug, and the time for natural recovery of ovarian function was evaluated. RESULTS: After 2 weeks of CTX/Bu injection, ovarian and uterine weights, and ovarian function were decreased sharply. Cisplatin treatment for 10 days resulted in a significant decrease in ovarian and uterine weight, and ovarian function. When POF was induced for at least 2 weeks for CTX/Bu and for at least 10 days for cisplatin, ovarian function did not recover naturally for 2 weeks and 1 week, respectively. CONCLUSIONS: These results suggest that CTX/Bu should be treated for at least 2 weeks and cisplatin for at least 10 days to establish the most effective primary ovarian insufficiency mouse model.

Pregnancy-related osteoporosis and spinal fractures.

Pregnancy-related osteoporosis is a very rare condition characterized by the occurrence of fracture during pregnancy or the puerperium. Despite its relative rarity, it can be a dangerous condition that causes severe back pain, height loss and disability. Normal physiologic changes during pregnancy, genetic or racial difference, obstetrical history and obstetrical disease, such as preterm labor or pregnancy-induced hypertension, are presumed risk factors of pregnancy-related osteooporosis. However, exact etiology and pathogenesis are uncertain. The management and natural history are still poorly defined. Traditional medications for osteoporosis are calcium/vitamin D and bisphosphonate. Concerns with bisphosphonate include accumulation in bone and fetal exposure in subsequent pregnancies. The newly developed medication, teriparatide, has shown good results. We report six cases of pregnancy-related osteoporosis and spinal fracture with literature review.

Laparoscopically assisted suprapubic surgery for adnexal tumors under epidural anesthesia.

OBJECTIVE: To evaluate the feasibility and safety of laparoscopically assisted surgery for benign ovarian tumors via a single suprapubic incision under epidural anesthesia. METHODS: Forty-three patients underwent laparoscopically assisted surgery via a single suprapubic incision under epidural anesthesia. Types of surgery were classified as follows: type I - suprapubic incision surgery without laparoscopic support, type II - suprapubic incision surgery with laparoscopic support but without CO2 inflation; and type III - suprapubic incision surgery with laparoscopic support and CO2 inflation. RESULTS: Type I, II, and III procedures were performed on 16, 21, and six patients, respectively. Most patients (n = 35) were discharged on postoperative day 1 or 2. No surgical complication was encountered. Types of surgery exhibited different surgical characteristics. Type I was adopted for larger diameter tumors than types II or III (p = .016), whereas type III had a longer operative time (p = .024) than types I and II. Other characteristics, such as age, body mass index, and length of hospital stay, did not differ significantly among surgical types. CONCLUSION: Laparoscopically assisted surgery for adnexal tumors via a single suprapubic incision under epidural anesthesia is feasible and safe, and should be viewed as an alternative approach to conventional minimally invasive surgery.

Ruptured Hemorrhagic Corpus Luteum Cyst in an Undescended Ovary: A Rare Cause of Acute Abdomen.

BACKGROUND: Undescended ovaries are typically detected during infertility evaluations and are frequently associated with uterine malformations. Ruptured hemorrhagic corpus luteum cyst of an undescended ovary is an unusual cause of acute abdomen in an adolescent. CASE: A 15-year-old girl presented with right lower quadrant pain, nausea, and vomiting, and transabdominal sonography and magnetic resonance imaging of the pelvis showed a 10 cm × 5 cm sized cystic mass at the level of the pelvic brim, anterior to the psoas muscle suggestive of a retroperitoneal hemorrhagic cyst. At surgery, the uterus and left adnexa appeared normal, but the right ovary was not visible within the pelvic cavity, and the right pelvic retroperitoneum was distended. After opening the retroperitoneum and aspirating blood clots, the undescended ovary with a ruptured cyst was visualized within the retroperitoneum. Right ovarian wedge resection was performed and the right ovary was repositioned in the pelvic cavity. SUMMARY AND CONCLUSION: Rupture of a corpus luteum cyst in an undescended ovary should be included in the differential diagnosis of acute abdomen in adolescents.

Ovarian Cavernous Hemangioma Presenting as a Large Growing Mass in a Postmenopausal Woman: A Case Report and Review of the Literature.

Ovarian hemangiomas are usually of the cavernous type, and are rarely encountered. A 73-year-old woman presented with lower abdominal discomfort. Subsequent physical examination depicted a palpable mass in the lower abdomen. Abdominopelvic computed tomography (CT) revealed a well-circumscribed mass with thin septa measuring 12.1 × 9.0 cm in the right ovary. Levels of the tumor markers cancer antigen (CA)-125 and CA 19-9 were within the normal range. At laparoscopy, the tumor was found to be confined to the right ovary and to have a smooth surface. The final histopathological result was ovarian cavernous hemangioma. Microscopically, the mass consisted of multiple, dilated, blood-filled vascular channels separated by loose connective tissue, and all were lined by a single layer of flattened endothelium. The authors present a case of ovarian cavernous hemangioma presenting as a large growing mass in a postmenopausal woman and review previously published literature.

The Association between Serum Uric Acid Level and Incidence of Metabolic Syndrome according to Menopausal Status in Korean Women.

OBJECTIVES: The aim of this study is to investigate the association between serum uric acid level and metabolic syndrome according to menopausal status in Korean women. METHODS: A total of 2,241 women who visited to the health promotion center at Pusan National University Hospital from 2010 to 2014 were included in this cross-sectional study. Self-report questionnaires and interviews with healthcare providers were used to assess disease history, medication history, menstrual history and body size measuring. Anthropometric measurements and laboratory results were compared as presence of metabolic syndrome and menopausal status by student-t test. Logistic regression analysis was performed between presence of metabolic syndrome and presumable predictive factors, such as age, menopause and serum uric acid. RESULTS: The prevalence rate of metabolic syndrome were 7.45% (63/846) in pre-menopausal group and 23.87% (333/1395) in menopausal group. Serum uric acid level was higher in menopausal women than premenopausal women (4.6 ± 1.1 vs. 4.3 ± 0.9. P = 0.000). And, its concentration was also higher in metabolic syndrome than normal women regarding of menopausal statue (premenopause 4.7 ± 1.1 vs. 4.2 ± 0.8, P = 0.001, menopause 4.9 ± 1.3 vs. 4.5 ± 1.0, P = 0.000). Multiple logistic regression analysis showed serum uric acid and age have relationship with metabolic syndrome (OR: 1.453, 95% confidence interval [CI]: 1.074-1.111, P = 0.000; OR: 1.092, 95% CI: 1.305-1.619, P = 0.000). CONCLUSION: We could find out some potential of uric acid as predictive factor for metabolic syndrome in premenopausal and menopausal group. Further investigation is required to clarify the relationship between serum uric acid, menopause and metabolic syndrome.