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971.
BACKGROUND: Spontaneous regression of Langerhans cell histiocytosis (LCH) has been reported in skin, bone, and pulmonary lesions. However, such phenomena in the central nervous system (CNS) have not been described previously. CASE DESCRIPTION: A case of LCH in the CNS with spontaneous regression is reported. A 2-year-old boy presented with general convulsion followed by frequent vomiting and diabetes insipidus. Magnetic resonance imaging (MRI) scan revealed numerous multifocal nodules predominantly in the left frontal lobe. The patient underwent surgery to remove part of the frontal lesion. Subsequent to surgery, residual lesions showed regression without any additional treatment, and clinical symptoms also subsided. The multiple lesions disappeared completely and did not relapse during 5-year observation. CONCLUSION: Surgical resection and/or adjuvant therapy such as radiation and chemotherapy has been performed for the treatment of LCH in the CNS. However, there may be a subgroup of patients with multifocal brain LCH that regress spontaneously. Further clinical study is required to establish the natural course and prognostic factors of this disease. 相似文献
972.
Belibi FA Reif G Wallace DP Yamaguchi T Olsen L Li H Helmkamp GM Grantham JJ 《Kidney international》2004,66(3):964-973
BACKGROUND: Progressive cyst enlargement, the hallmark of autosomal-dominant polycystic kidney disease (ADPKD) and autosomal-recessive (ARPKD) polycystic kidney disease, precedes the eventual decline of function in these conditions. The expansion of individual cysts in ADPKD is determined to a major extent by mural epithelial cell proliferation and transepithelial fluid secretion. This study determined if common receptor-mediated agonists and an anonymous lipid stimulate the production of 3' 5'-cyclic monophosphate (cAMP) in mural epithelial cells from the two major types of human cystic diseases. METHODS: cAMP responses to maximally effective concentrations of renal agonists were determined together with measurements of transepithelial anion current and cellular proliferation and extracellular signal-related kinase (ERK 1/2) expression in primary cultures of epithelial cells from human ADPKD and ARPKD cysts. RESULTS: The rank orders of responses to ligands for ADPKD and ARPKD cells were identical: epinephrine > desmopressin (DDAVP) approximately arginine vasopressin (AVP) > adenosine > prostaglandin E(2) (PGE(2)) > parathyroid hormone (PTH). cAMP concentrations elevated by epinephrine, DDAVP, adenosine, and PGE(2) were diminished by receptor-specific inhibitors. Pools of cyst fluid collected individually from 16 of 19 ADPKD kidneys increased, to varying degrees, cAMP levels in ADPKD and ARPKD cells. PGE(2), beta-adrenergic and AVP antagonists partially inhibited cAMP accumulation in response to fluids from three kidneys, but a large portion of the endogenous activity was attributed to yet-to-be identified bioactive lipid, designated cyst activating factor (CAF). CAF stimulated cAMP production in ADPKD and ARPKD cells, activated ERK(1/2), and increased cellular proliferation in ADPKD cells. CAF increased positive short circuit current (I(SC)) in polarized ADPKD and T-84 monolayers, indicating stimulation of net anion secretion. CONCLUSION: Endogenous adenylyl cyclase agonists promote cell proliferation and electrolyte secretion of human ADPKD and ARPKD cells in vitro. We suggest that increased levels of cAMP may accelerate cyst growth and overall renal enlargement in patients with PKD. 相似文献
973.
Maki N Komatsuda A Wakui H Oyama Y Kodama T Ohtani H Kigawa A Aiba N Imai H Motegi M Yamaguchi A Sawada K 《Clinical nephrology》2004,61(3):185-190
BACKGROUND: Fabry disease is an X-linked recessive disorder resulting from a deficiency of lysosomal alpha-galactosidase A (alpha-Gal A). Chronic renal failure is an important cause of death in patients with Fabry disease. We report on patients with Fabry disease (a hemizygous male and his mother) due to a nonsense mutation (R220X) in the alpha-Gal A gene. METHODS: The proband, a 41-year-old man, and his 71-year-old mother presented with renal and cardiac manifestations of Fabry disease. Histological examination and molecular analysis of the alpha-Gal A gene were performed. RESULTS: Typical histological findings of Fabry disease were observed in a renal biopsy specimen from the proband and in renal and myocardial necropsy specimens from the mother. Sequencing of a full-length alpha-Gal A cDNA from the proband indicated a C-T transition at codon 220, resulting in substitution of the predictable termination for arginine (R220X). Examination of genomic alpha-Gal A DNA revealed that the proband was a hemizygote and the mother was a heterozygous carrier for the mutation. CONCLUSION: This is the first detailed report of family members with Fabry disease due to a nonsense mutation (R220X) in the alpha-Gal A gene. Our study indicates that this mutation causes the typical disease in both genders. 相似文献
974.
Yamaguchi S Sakata K Nakayama K Orito K Ikeda A Arakawa M Shigemori M 《No shinkei geka. Neurological surgery》2004,32(5):493-499
A 56-year-old woman with aortic regurgitation (AR) developd a high fever on April 25th, 2003, followed by the sudden onset of left hemiparesis and dysarthria on May 10th, 2003. MRI and MRA showed cerebral infarction due to occlusion of the right proximal portion of the middle cerebral artery. Streptococcus was isolated from arterial blood culture at the time of admission and cardiac examination such as echocardiography revealed active infective endocarditis. Cerebral angiography on the 31st day after the onset of symptoms demonstrated a fusiform-shaped aneurysm at the occluded M2 portion of the middle cerebral artery. Despite administration of antibiotics, a small subcortical hematoma was observed in the right temporal lobe surrounding the aneurysm on the 35th day. The direct surgery of aneurysmal trapping and resection was subsequently performed to prevent rebleeding. The sylvian fissure and perianeurysmal area were strongly adherent to granulation tissue and blood clot. After exposing the aneurysm, the dilated portion of the vessel was successfully trapped and resected. Other than residual left hemiparesis, the postoperative course was uneventful. Histological examination confirmed bacterial aneurysm due to bacterial embolization originating from infective endocarditis (IE). We report a rare case having a ruptured bacterial aneurysm of the middle cerebral arterial bifurcation requiring surgery following occlusion due to bacterial embolization after sepsis and meningitis due to infective endocarditis. 相似文献
975.
Yamaguchi S Kuroda S Ushikoshi S Ishikawa T Nanba R Hokari M Asano T Iwasaki Y 《No shinkei geka. Neurological surgery》2004,32(7):747-751
Combined therapy of direct sinus packing and surgical excision for intracranial dural arteriovenous fistula (dAVF) has not been reported in the literature. A 53-year-old male was admitted to our hospital due to sudden onset of seizure and consciousness disturbance. Plain CT scan showed subcortical hematoma in the right temporal lobe. Cerebral angiography revealed dAVF involved in the right transverse and sigmoid sinuses. The lesion was associated with retrograde venous drainage into the right cerebellum, temporal, and occipital lobes. Positron emission tomography (PET) showed typical findings of venous hypertension in the involved areas. MRI also demonstrated a high intensity lesion in the medulla oblongata, suggesting critical venous congestion. First, we aimed to pack the involved sinus through a minor craniotomy, but cannulation into the sinus was impossible probably because of a marked fibrosis in the involved sinus. Then, we completely exposed the involved sinus through craniotomy. Through a microcatheter inserted into the sinus, the lower part of the sigmoid sinus was directly packed, and the remaining lesion was excised. Postoperative course was uneventful. Disappearance of dAVF resolved the findings on PET and MRI. Combined therapy would be a safe, non-invasive, and useful option for patients with a complex intracranial dAVF. 相似文献
976.
Matsumoto H Kohno K Ishii D Mitsuhara T Yamaguchi Y Kohno K Takechi A Takeda T Sasaki U Ohta M 《No shinkei geka. Neurological surgery》2004,32(7):729-732
The authors report a case of Currarino triad with a combination of anterior sacral meningocele and mature teratoma, sacral body deformity, anorectal stenosis, and tethered cord. A newborn girl suffered from vomiting, abdominal distension and constipation. Initially, a diverting colostomy was performed at the age of one month. 7 months later, at the age of 8 months, we performed posterior sagittal anorectoplasty (PSARP): As a result, extirpation of teratoma, excision of meningocele, untethering of the spinal cord, and anorectoplasty were achieved simultaneously without complication. We suggest the use of an MRI to specify the presence of anosacral and spinal cord anomalies in patients with intractable constipation and we recommend combined pediatric and neurosurgical assessment and management for all cases of Currarino triad. 相似文献
977.
Preservation of the bone mineral density of the femur after surface replacement of the hip 总被引:8,自引:0,他引:8
Kishida Y Sugano N Nishii T Miki H Yamaguchi K Yoshikawa H 《The Journal of bone and joint surgery. British volume》2004,86(2):185-189
We investigated the effect of the Birmingham hip resurfacing (BHR) arthroplasty on the bone mineral density (BMD) of the femur. A comparative study was carried out on 26 hips in 25 patients. Group A consisted of 13 patients (13 hips) who had undergone resurfacing hip arthroplasty with the BHR system and group B of 12 patients (13 hips) who had had cementless total hip arthroplasty with a proximal circumferential plasma-spray titanium-coated anatomic Ti6A14V stem. Patients were matched for gender, state of disease and age at the time of surgery. The periprosthetic BMD of the femur was measured using dual-energy x-ray absorptiomentry of the Gruen zones at two years in patients in groups A and B. The median values of the BMD in zones 1 and 7 were 99% and 111%, respectively. The post-operative loss of the BMD in the proximal femur was significantly greater in group B than in group A. These findings show that the BHR system preserves the bone stock of the proximal femur after surgery. 相似文献
978.
Procedures of Choice for Resection of Primary and Recurrent Liver Metastases from Colorectal Cancer 总被引:5,自引:0,他引:5
Tanaka K Shimada H Ohta M Togo S Saitou S Yamaguchi S Endo I Sekido H 《World journal of surgery》2004,28(5):482-487
Although liver resection offers the only realistic chance of cure for patients with liver metastases from colorectal cancer, no consensus exists as to the procedure of choice for managing these tumors. Data from 193 patients who underwent hepatectomy for liver metastases from colorectal cancer and 26 of 193 patients who underwent repeat hepatectomy for recurrent metastases were collected. The suitability of resection was evaluated retrospectively based on known risk factors for recurrence and patterns of recurrence. On multivariate analysis, a positive surgical margin (SM+) was the only risk factor for recurrence after the initial resection (p < 0.01). SM+ (p < 0.01) and nonanatomic resection (p < 0·05) that was less than a sectionectomy (p < 0.05) were risk factors for recurrence after repeat hepatectomy. Multiple tumors (four or more) was the most common pattern of recurrence after initial hepatectomy, and recurrence close to the line of resection was most common after repeat hepatectomy. Based on tumor doubling times, recurrence after initial hepatectomy seemed to originate from the primary colorectal lesion, whereas recurrence after repeat hepatectomy was derived from a hepatic metastasis. Retrospective analysis suggests that hepatectomy with clear surgical margins is more important than anatomic resection for initial hepatectomy, and at least sectionectomy is necessary for repeat hepatectomy. 相似文献
979.
Fukushima A Ashizawa K Yamaguchi T Matsuyama N Hayashi H Kida I Imafuku Y Egawa A Kimura S Nagaoki K Honda S Katsuragawa S Doi K Hayashi K 《AJR. American journal of roentgenology》2004,183(2):297-305
OBJECTIVE: The purpose of our study was to evaluate the diagnostic performance of an artificial neural network (ANN) in differentiating among certain diffuse lung diseases using high-resolution CT (HRCT) and the effect of ANN output on radiologists' diagnostic performance. MATERIALS AND METHODS: We selected 130 clinical cases of diffuse lung disease. We used a single three-layer, feed-forward ANN with a back-propagation algorithm. The ANN was designed to differentiate among 11 diffuse lung diseases by using 10 clinical parameters and 23 HRCT features. Therefore, the ANN consisted of 33 input units and 11 output units. Subjective ratings for 23 HRCT features were provided independently by eight radiologists. All clinical cases were used for training and testing of the ANN by implementing a round-robin technique. In the observer test, a subset of 45 cases was selected from the database of 130 cases. HRCT images were viewed by eight radiologists first without and then with ANN output. The radiologists' performance was evaluated with receiver operating characteristic (ROC) analysis with a continuous rating scale. RESULTS: The average area under the ROC curve for ANN performance obtained with all clinical parameters and HRCT features was 0.956. The diagnostic performance of four chest radiologists and four general radiologists was increased from 0.986 to 0.992 (p = 0.071) and 0.958 and 0.971 (p < 0.001), respectively, when they used the ANN output based on their own feature ratings. CONCLUSION: The ANN can provide a useful output as a second opinion to improve general radiologists' diagnostic performance in the differential diagnosis of certain diffuse lung diseases using HRCT. 相似文献
980.
Yamaguchi Y Yamanaka M Nishimura K Ichikawa Y Nagano S Toki K 《Hinyokika kiyo. Acta urologica Japonica》2004,50(10):695-698
We report two cases of spontaneous rupture of renal angiomyolipoma (AML). In the first case, a 22-year-old woman was admitted with lower abdominal pain. She was diagnosed with rupture of left renal AML. Transcatheter arterial embolization (TAE) was performed for three times to preserve renal function, and the size of AML decreased to 6.5 cm from 10 cm. In the second case (74-year-old woman), the chief complaint was lower abdominal pain. The clinical diagnosis of this patient was rupture of right renal AML. The size of this AML markedly reduced due to TAE. TAE is an effective therapy for rupture of renal AML. 相似文献