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991.
Hiroyuki Kanzaki Mirei Chiba Yoshinobu Shimizu Hideo Mitani 《Journal of bone and mineral research》2002,17(2):210-220
Previously, we discovered that periodontal ligament (PDL) cells not only support osteoclastogenesis through cell-to-cell contact, but also inhibit the formation of tartrate-resistant acid phosphatase-positive (TRAP+) multinucleated cells by a producing soluble factor(s). Furthermore, PDL cells express both receptor activator of nuclear factor kappaB ligand (RANKL) and osteoprotegerin (OPG) messenger RNA (mRNA). Clinically, "ankylosed teeth," which lack periodontal ligament, cannot be moved with orthodontic tooth treatment. From this, we hypothesized that PDL cells under mechanical stress should play a pivotal role in osteoclast formation during orthodontic tooth movement. This study examined how mechanical stress affects the osteoclastogenesis-supporting activity of PDL cells. PDL cells were compressed continuously and then cocultured with peripheral blood mononuclear cells (PBMCs) for 4 weeks. PDL cells under mechanical stress up-regulated osteoclastogenesis from PBMCs. Furthermore, the expression of RANKL mRNA and protein in PDL cells increased with compressive force in parallel with the change in the number of osteoclasts. In addition, cyclo-oxygenase 2 (COX-2) mRNA expression was induced by compressive force, and indomethacin inhibited the RANKL up-regulation resulting from compressive force. PDL cells under compressive force exhibited significantly increased prostaglandin E2 (PGE2) production in comparison with control PDL cells. Exogenous PGE2 treatment increased RANKL mRNA expression in PDL cells. Interestingly, OPG expression remained constant throughout compressive force or PGE2 treatment. In conclusion, compressive force up-regulated RANKL expression in PDL cells. Furthermore, RANKL up-regulation in mechanically stressed PDL cells was dependent on PGE2. 相似文献
992.
993.
Kubota T Hirai H Shimizu N Sawada A Kondou H Nakajima S Harada T Shima M 《Pediatric nephrology (Berlin, Germany)》2002,17(5):367-369
We present a 13-year-old boy who developed hyperthyroidism during the clinical course of idiopathic nephrotic syndrome treated
with glucocorticoid. He had a second relapse of minimal change nephrotic syndrome, and complete remission of nephrotic syndrome
was achieved immediately with oral glucocorticoid. However, when the steroid dosage was reduced, signs of hyperthyroidism
such as systolic hypertension and tachycardia were observed. Laboratory findings revealed thyroid-stimulating hormone (TSH)
below 0.05 μU/ml, free tri-iodothyronine of 16.1 pg/ml, free thyroxine of 5.6 ng/dl, and anti-TSH receptor antibody of 90%.
Thus, a diagnosis of hyperthyroidism was made and treatment with thiamazol was started. Massive proteinuria may decrease the
activity of hyperthyroidism due to urinary loss of thyroid hormones. A decrease in glucocorticoid dosage may also be involved
in the development of hyperthyroidism due to a reduced immunosuppressive effect.
Received: 11 July 2001 / Revised: 22 October 2001 / Accepted: 27 November 2001 相似文献
994.
Iwasaki Y Shimoda M Furihata T Rokkaku K Sakuma A Ichikawa K Fujimori T Kubota K 《Surgery today》2002,32(11):1019-1022
We report a rare case of biliary papillomatosis arising in a congenital choledochal cyst, with an anomalous junction of the
pancreatobiliary ductal system (AJPBDS). A 50-year-old woman was admitted to our department with epigastralgia, and imaging
studies showed two masses in the cystic common bile duct and an AJPBDS. We made a preoperative diagnosis of biliary tract
cancer, considering the size of the masses and the presence of the AJPBDS, and performed a pylorus-preserving pancreatoduodenectomy.
The resected specimen contained two papillary tumors, which were subsequently diagnosed as benign papillomas. Histopathological
and oncological examinations indicated that the lesions were involved in the development and progression of carcinogenesis
because a point mutation of the K-ras gene and overexpression of p53 protein were detected. These findings suggest that biliary papillomatosis is a precancerous
lesion induced by an AJPBDS.
Received: December 25, 2001 / Accepted: May 7, 2002
Reprint requests to: K. Kubota 相似文献
995.
Mikami I Koizumi K Shimizu K Kawamoto M Hemmi S Haraguchi S Hirata T Akiyama H Hirai K Tanaka S 《Surgery today》2002,32(4):351-353
We report herein a rare case of a functional mediastinal parathyroid cyst. A mediastinal tumor was detected by a chest X-ray
film and subsequent computed tomography (CT) scan in a 68-year-old woman who was asymptomatic. Biochemical examination revealed
that her serum calcium and intact-parathyroid hormone (i-PTH) levels were above the normal range. The findings of chest CT
and magnetic resonance imaging suggested a cystic mass. The mass, which adhered tightly to its surrounding structures, was
resected through a median sternotomy. The patient had an uneventful postoperative course, and her serum calcium and i-PTH
levels rapidly returned to within the normal range.
Received: March 21, 2001 / Accepted: September 11, 2001 相似文献
996.
Abstact
A solitary recurrence of gastric carcinoma in the peritoneal cavity is extremely rare. We herein present a case of solitary
intraperitoneal recurrence in a patient with α-fetoprotein (AFP)-producing gastric carcinoma. As far as we can determine,
this is the first report of such a form of recurrence in a patient with gastric carcinoma who underwent a successful resection.
A review of our eight patients who had AFP-producing gastric carcinoma showed a frequent association with hepatic metastasis
and a poor prognosis as has been reported previously. Our patient received intra-arterial chemotherapy with low-dose cisplatin
and 5-fluorouracil to prevent hepatic recurrence, but eventually developed multiple hepatic metastases after ceasing this
therapy. Therefore, adjuvant intra-arterial chemotherapy may have altered the site of first recurrence in this patient.
Received: June 6, 2001 / Accepted: November 20, 2001 相似文献
997.
Kato T Kojima T Shimizu T Sasaki H Abe M Okushiba S Kondo S Kato H Sato H 《Surgery today》2002,32(1):81-85
We describe herein a case of inflammatory malignant fibrous histiocytoma (IMFH) of the gallbladder that subsequently metastasized
to the ascending colon and later to the stomach. A 70-year-old Japanese man with a palpable mass in the right upper quadrant
of the abdomen was referred to our hospital for investigation and treatment. Laboratory data showed severe leukocytosis and
elevated serum granulocyte colony-stimulating factor (G-CSF) concentrations. A laparotomy was performed, and the tumor was
excised en bloc with the gallbladder and part of the liver bed. Histopathologically, the tumor was composed of ordinary malignant
fibrous histiocytoma (MFH) components characterized by pleomorphic tumor cells, bizarre giant cells, and conventional spindle
cells in a storiform growth pattern, as well as a xanthogranulomatous component, including inflammatory cells, foamy histiocytes,
and plasma cells. Immunohistochemical study revealed that the pleomorphic tumor cells and bizarre giant cells were positive
for antibodies against α1-antitrypsin and α1-antichymotrypsin. The final pathologic diagnosis was IMFH. The tumor cells were diffusely positive for anti-G-CSF monoclonal
antibody, and the inflammatory reaction subsided immediately after tumor resection, strongly suggesting that the primary tumor
cells produced G-CSF. This patient is still alive with no signs of recurrence more than 3 years after his primary operation,
which to our knowledge is the longest survival period ever reported. Therefore, visceral IMFH is manageable in some cases
by resecting the primary and isolated metastatic lesions.
Received: October 11, 2000 / Accepted: May 15, 2001 相似文献
998.
Kamiyoshihara M Sakata K Otani Y Kawashima O Takahashi T Morishita Y 《Surgery today》2002,32(5):402-405
A 72-year-old man was found to have an endobronchial lipoma accompanied with primary lung cancer. A left lower lobectomy with
a mediastinal lymph node dissection and a sleeve resection of the lingual bronchus with telescoping bronchial anastomosis
were done. The pathological staging was T1N2M0, stage IIIA. A histological examination showed well-differentiated squamous
cell carcinoma in segment 10, in addition to the presence of mature adipose tissue which was diagnosed to be a benign endobronchial
lipoma originating from the lingual bronchus. The postoperative course was uneventful and the patient was discharged 13 days
after the operation. However, he had a recurrence in the subcarinal lymph node, and died 8 months after surgery.
Received: March 2, 2001 / Accepted: November 20, 2001 相似文献
999.
Polypoidal choroidal vasculopathy: natural history 总被引:13,自引:0,他引:13
Uyama M Wada M Nagai Y Matsubara T Matsunaga H Fukushima I Takahashi K Matsumura M 《American journal of ophthalmology》2002,133(5):639-648
PURPOSE: The present study was performed to clarify the long-term natural history of polypoidal choroidal vasculopathy (PCV). DESIGN: Prospective, consecutive observational case series. METHODS: Fourteen eyes of 12 consecutive patients with PCV were prospectively followed in our clinic for at least 2 years without any treatment after a first visit to the clinic between February 1996 and November 1998. All patients underwent complete ophthalmologic examination, color fundus photography, and fluorescein and indocyanine green (ICG) angiography at regular intervals. Inclusion criteria were as follows: eyes had serous and/or hemorrhagic pigment epithelium detachment (PED) and retinal detachment in the posterior pole, and ICG angiography revealed a branching vascular network with polypoidal dilations at the terminals of the network. Exclusion criteria were as follows: other diseases such as exudative age-related macular degeneration, high myopia, angioid streaks, and presumed ocular histoplasmosis syndrome, and patients who previously underwent any ocular surgery. RESULTS: Patients were followed for mean of 39.9 months (range, 24-54 months). PCV was present in 10 (83%) men and two women and in the elderly (mean age 68.1 years), usually unilateral (83%) with vascular lesions located at the macula (93%). The PCV manifested in two patterns, exudative and hemorrhagic. In the exudative pattern, serous PED and retinal detachment were predominant at the macula. The hemorrhagic pattern was characterized by hemorrhagic PED and subretinal hemorrhage at the macula. ICG angiography revealed polypoidal choroidal neovascularization that was changeable in appearance and repeatedly grew and spontaneously regressed, but the vascular network persisted. In some eyes, a collection of small aneurysmal dilations of vessels resembling a cluster of grapes appeared and all of them had marked bleeding and leakage and worse outcome. CONCLUSION: Polypoidal choroidal vasculopathy is a long persistent chronic disease and the patients had a variable course. Fifty percent of the patients had a favorable course. In the remaining half of the patients, the disorder persisted for a long time with occasional repeated bleeding and leakage, resulting in macular degeneration and visual loss. Eyes with a cluster of grapes-like polypoidal dilatations of the vessels had a high risk for severe visual loss. 相似文献
1000.
Handa T Mukuno K Niida T Uozato H Tanaka S Shimizu K 《Journal of refractive surgery (Thorofare, N.J. : 1995)》2002,18(1):58-62
PURPOSE: To elucidate the diurnal variation of human corneal curvature with regard to gender and menstrual cycle. METHODS: Changes in corneal curvature and intraocular pressure (IOP) were measured over 24 hours in 14 young adults using corneal topography and a non-contact tonometer. In study 1, seven males and seven females (after menses) were measured. In study 2, four females out of the seven volunteers who participated in study 1 were measured again during menses. RESULTS: The females after menses showed a remarkable diurnal variation throughout 24 hours. A significant difference between the light-wake periods and dark-sleep periods of 0.83 +/- 0.15 D was found (P < .01). Corneal curvature was significantly flatter during menses than after menses in the light-wake period (P < .05). In the males, no significant diurnal change (0.21 +/- 0.12 D) was measured in corneal curvature. CONCLUSIONS: Diurnal variation of corneal curvature was significant, approximately 0.83 D in young females after menses, and corneal curvature became flatter during menses in young females. Diurnal variation of corneal curvature is an important parameter for planning refractive surgery and contact lens wear. 相似文献