Gigantic jets between a thundercloud and the ionosphere.

Transient luminous events in the atmosphere, such as lighting-induced sprites and upwardly discharging blue jets, were discovered recently in the region between thunderclouds and the ionosphere. In the conventional picture, the main components of Earth's global electric circuit include thunderstorms, the conducting ionosphere, the downward fair-weather currents and the conducting Earth. Thunderstorms serve as one of the generators that drive current upward from cloud tops to the ionosphere, where the electric potential is hundreds of kilovolts higher than Earth's surface. It has not been clear, however, whether all the important components of the global circuit have even been identified. Here we report observations of five gigantic jets that establish a direct link between a thundercloud (altitude approximately 16 km) and the ionosphere at 90 km elevation. Extremely-low-frequency radio waves in four events were detected, while no cloud-to-ground lightning was observed to trigger these events. Our result indicates that the extremely-low-frequency waves were generated by negative cloud-to-ionosphere discharges, which would reduce the electrical potential between ionosphere and ground. Therefore, the conventional picture of the global electric circuit needs to be modified to include the contributions of gigantic jets and possibly sprites.

Clinical outcomes of magnetic resonance-guided focused ultrasound surgery for uterine myomas: 24-month follow-up.

OBJECTIVES: To assess the volume reduction ratio, symptom improvement and reintervention rate following magnetic resonance-guided focused ultrasound surgery (MRgFUS) for uterine myomas. METHODS: A total of 91 Japanese women with symptomatic myomas underwent MRgFUS between June 2004 and June 2008 using the ExAblate 2000 system. The volume change ratio was calculated at 6, 12 and 24 months following MRgFUS based on T2-weighted magnetic resonance images. The symptom severity score (SSS) was examined before and after the treatment (at 3, 6, 12 and 24 months). Additional post-MRgFUS treatments, such as hysterectomy, myomectomy, uterine artery embolization or repeat MRgFUS, were recorded and the reinterventional treatment rates were compared according to the signal intensity of pretreatment T2-weighted magnetic resonance images of the myomas. RESULTS: The mean volume change ratios of low- and intermediate-intensity (Type 1/2) myomas were -36.5% 6 months post-procedure and -39.5% 24 months post-procedure. The mean +/- SD SSS value for patients with Type 1/2 myomas before MRgFUS was 35.1 +/- 21.0, and the values diminished significantly during the 24-month follow-up period to a mean value of around 15.0. High-intensity (Type 3) myomas were not observed to have decreased in size 6 months after MRgFUS. Of the 45 Type 1/2 myoma patients with complete follow-up, seven required reinterventional treatment within 24 months. The reintervention rates were 14.0% for Type 1/2 patients and 21.6% for Type 3 patients at 24 months post-treatment. CONCLUSIONS: Moderate volume reductions of Type 1/2 myomas were noted following MRgFUS, and the reduction in SSS values and the relatively low reintervention rates observed are encouraging. We found MRgFUS to be an appropriate treatment method for Type 1/2 uterine myomas.

Non-invasive magnetic resonance-guided focused ultrasound treatment of uterine fibroids in a large Japanese population: impact of the learning curve on patient outcome.

OBJECTIVES: To describe the learning curve effect of magnetic resonance-guided focused ultrasound surgery (MRgFUS) on the outcomes of patients treated for uterine fibroids in four centers in Japan. METHODS: The extent of fibroid ablation (often used to measure treatment success) was evaluated using the non-perfused volume (NPV) ratio in 287 Japanese patients. The patients were divided into two equal groups according to the chronological treatment time and results were compared between these groups to estimate the learning curve effect. Results were also compared with published data from clinical trials. RESULTS: The NPV ratio increased chronologically, from 39.3% to 54.0% (P < 0.001), indicating increasing effectiveness of the treatment with experience. The mean NPV ratios for the entire patient population were over double that of previous clinical trials (46.6% vs. 21.9%; P < 0.001). No serious complications were reported. CONCLUSION: The learning process and accumulation of data on MRgFUS enable the optimization of treatments in order to safely achieve large NPV ratios and sustained clinical benefit.

Uterine myxoid leiomyosarcoma and CYVADIC-etoposide therapy.

OBJECTIVES: To conduct a pathological characterization of rare uterine myxoid leiomyosarcoma (MLS) and establish an effective chemotherapy for metastasis after hysterectomy. METHODS: Histological and immunohistochemical methods were used to characterize the type of uterine MLS in a 39-year-old female. For multiple lung metastases found 3 months after operation, CYVADIC (400 mg cyclophosphamide, 1 mg vincristine, 50 mg epirubicin and 400 mg dacarbazine per body for one course) and oral etoposide (50 mg/body per day for 2 weeks) were applied. RESULTS: The rapidly enlarging uterine tumors exhibited gelatinous cut surfaces, a high count of 30 mitotic cells per 10 hpf and mucinous stroma, indicating a rare high-mitotic type of uterine MLS. The two-course CYVADIC-etoposide therapy was effective for disseminated pulmonary metastases. CONCLUSION: The present MLS was a rare high-mitotic type. CYVADIC-etoposide was an optional effective chemotherapy for lung metastasis in this case.

[A case of ureteral stenosis caused by ureteral endometriosis].

A case of ureteral endometriosis is reported A 42-year-old woman visited our clinic on December 3, 1985, with the complaint of right lumbago. Intravenous pyelography showed right hydronephrosis and retrograde pyelography revealed ureteral stenosis at 11 cm from right ureteral orifice and 2 cm long. Primary right ureter tumor was suspected. The operation was performed on January 16, 1986 and revealed periureteral mass. The mass was removed with ureter and ureteroureterostomy was performed. The pathological diagnosis was extrinsic ureteral endometriosis. Ureteral endometriosis has rarely been described and only 17 cases have been reported previously in Japan.

Unsuspected uterine leiomyosarcoma: magnetic resonance imaging findings before and after focused ultrasound surgery.

Uterine leiomyosarcoma, initially diagnosed as leiomyoma on magnetic resonance (MR) images, was disclosed after focused ultrasound surgery (FUS). The tumor did not display high signal intensity on either T1- or T2-weighted images on the patient's first visit. Four months thereafter, T2-weighted images revealed a high signal intensity area within the tumor, while T1-weighted images showed low signal intensity. Six months after FUS, the nonperfused volume calculated on meglumine gadoterate-enhanced T1-weighted images decreased markedly and an intermediate signal intensity in a circular area on T2-weighted images appeared to be atypically increasing in volume. After laparoscopic myomectomy, this tumor was diagnosed as uterine leiomyosarcoma coexistent with leiomyoma. The early stages of uterine leiomyosarcoma are clinically difficult to diagnose; therefore, both careful monitoring during FUS and close follow-up after the procedure are vital.

Metabolism of (4-14C)progesterone and (7alpha-3H)pregnenolone by human ovaries perfused in vitro.

Nine human ovaries were perfused in vitro with [4-14C]progesterone and in addition one ovary with [7-3H]pregnenolone. From the perfusate unchanged progesterone and five different metabolites were isolated: 20alpha-dihydroprogesterone, 17alpha-hydroxyprogesterone, 16alpha-hydroxyprogesterone, 5alpha-pregnane-3,20-dione and 4-androstene-3,17-dione. In the ovarian tissue saturated pregnane derivatives were the main metabolites. When [3H]pregnenolone and [14C]progesterone were perfused simultaneously a stimulation of delta4-5-isomerase and 3beta-dehydrogenase activity by HCG was demonstrated.

Secretion of progesterone by human overies perfused in vitro.

A system for the perfusion of isolated human ovaries is described. Krebs-Ringer bicarbonate buffer (pH 7.4) containing glucose, sodium lactate and pyruvate was perfused at a flow rate of 5-8 ml/min at 37 degrees C through the ovarian artery. Oxygen uptake, LDH-activity, pH and progesterone secretion were determined as parameters of viability of the perfused organ. Our results demonstrate that a relatively simple system used for perfusion was able to preserve ovarian function for at least two hours. This experimental design should not be regarded as physiological but in addition to other experimental approaches it might provide information on the physiology of the human ovary. Though lower values of progesterone secretion than in vivo were found, a correlation of secretion and functional stage of the ovaries could be demonstrated.

Ovarian fibromatosis with minor sex cord elements.

Ovarian fibromatosis is very rare, and the one with focal proliferations of sex cord type elements is extraordinarily rare. A 31-year-old patient developed the bilateral ovarian enlargements and complained of lower abdominal pain, Pathology indicated that these tumors were ovarian fibromatosis with minor sex cord elements. Our two-step operation involved the first right salpingo-oophorectomy for histological examination and the subsequent enucleation of the left ovarian tumor alone. The patient conceived 10 months after operation.

Observations of thermospheric wind velocities and temperatures by the use of a Fabry-Perot Doppler imaging system at Syowa Station, Antarctica.

A new optical instrument, the Fabry-Perot Doppler imaging system (FPDIS), has been developed for observations of two-dimensional distributions of thermospheric wind velocities and temperatures by the measurement of the Doppler shift and width of the aurora or of the airglow emission lines of atomic oxygen OI 557.7 nm and OI 630.0 nm over a wide field of view (165°). A technique for the derivation of Doppler temperatures and wind velocities was developed by use of a truncated Fourier series. Thermospheric wind velocities and temperatures have been obtained with unprecedented high temporal (1 min) and spatial (24 points for an all-sky image) resolutions. Errors in the derived wind velocities and temperatures are estimated to be less than 25 m/s and 100 K, respectively, for inner-fringe positions and 35 m/s and 170 K for outer-fringe positions, respectively. This system was applied to observations of thermospheric wind velocities and temperatures at Syowa Station (69.00° S, 39.58° E), Antarctica for the period of one austral winter in 1990.

Laser heterodyne spectrometer using a liquid nitrogen cooled tunable diode laser for remote measurements of atmospheric O(3) and N(2)O.

A laser heterodyne spectrometer with a tunable diode laser as a local oscillator has been developed for ultrahigh resolution IR spectroscopy of the absorption spectra of trace constituents in the earth's atmosphere. The spectral resolution and SNR of the developed system are 0.0013 cm(-1) and ~500, respectively. This performance is sufficient for retrieving the altitude profile of atmospheric O(3) through an inversion method. The altitude profile of atmospheric N(2)O has been also obtained for the first time with this laser heterodyne technique. The high resolution and high SNR have been accomplished by adopting a tunable diode laser which operates at liquid nitrogen temperature and by developing an effective technique to eliminate the optical feedback of the local oscillator laser beam.

Glass-type hydrogen and deuterium absorption cells developed for D/H ratio measurements in the Martian atmosphere.

Hydrogen and deuterium absorption cells of a new glass type have been developed for the D/H ratio measurements on the Japanese Mars mission PLANET-B. The H/D cells work as narrow-band rejection filters for the H/D Lyman-alpha line, respectively, when the H or D atoms are produced at a heated filament inside the cells. The absorption profiles of the cells were successfully measured with a high-resolution vacuum ultraviolet spectrometer with a wavelength resolution of 6.6 x 10(-4) nm. The derived optical thickness was found to be ~7 and ~14 for the hydrogen and deuterium cells, respectively. It was also found that the derived temperature of atomic gas ranges between the temperature of the cell wall and that of the heated filament, and it increases with increasing filament temperature. The measured profiles showed that the absorption efficiencies of the developed absorption cells are sufficient to observe the D/H ratios of the Martian atmosphere.