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81.

Background

To investigate the expression of parathyroid hormone (PTH)/PTH-related peptide (PTHrP) receptor 1 (PTH1R) in clinical specimens of normal and diseased bladders. PTHrP is a unique stretch-induced endogenous detrusor relaxant that functions via PTH1R. We hypothesized that suppression of this axis could be involved in the pathogenesis of bladder disease.

Methods

PTH1R expression in clinical samples was examined by immunohistochemistry. Normal kidney tissue from a patient with renal cancer and bladder specimens from patients undergoing ureteral reimplantation for vesicoureteral reflux or partial cystectomy for urachal cyst were examined as normal control organs. These were compared with 13 diseased bladder specimens from patients undergoing bladder augmentation. The augmentation patients ranged from 8 to 31 years old (median 15 years), including 9 males and 4 females. Seven patients had spinal disorders, 3 had posterior urethral valves and 3 non-neurogenic neurogenic bladders (Hinman syndrome).

Results

Renal tubules, detrusor muscle and blood vessels in normal control bladders stained positive for PTH1R. According to preoperative urodynamic studies of augmentation patients, the median percent bladder capacity compared with the age-standard was 43.6% (range 1.5–86.6%), median intravesical pressure at maximal capacity was 30 cmH2O (range 10–107 cmH2O), and median compliance was 3.93 ml/cmH2O (range 0.05–30.3 ml/cmH2O). Detrusor overactivity was observed in five cases (38.5%). All augmented bladders showed negative stainings in PTH1R expression in the detrusor tissue, but positive staining of blood vessels in majority of the cases.

Conclusions

Downregulation of PTH1R may be involved in the pathogenesis of human end-stage bladder disease requiring augmentation.  相似文献   
82.
Summary Behaviour and fate of the transplanted articular cartilage were studied in 180 adult rabbits, using the scanning electron microscope, histological staining and autoradiographic examination.The junction between the host cartilage and the transplanted cartilage was covered with thin connective tissue layers which extended from the edges 4 weeks after transplantation.After the 24th week of transplantation the cartilage tissue appeared to be degenerating at the periphery of the graft.However, in the middle portion of the graft surviving cartilage cells were observed using 35S autoradiography.
Résumé Comportement et évolution du cartilage articulaire transplanté ont été étudiés chez 180 lapins adultes par microscopie électronique, colorations histologiques et autoradiographies.Quatre semaines après la transplantation, une fine couche de tissue conjonctif qui s'étend depuis les bords recouvre la jonction entre le cartilage du receveur et le cartilage transplanté.Vingt-quatre semaines après la transplantation, le tissu cartilagineux commence à dégénérer à la périphérie du greffon. Cependant, à la partie centrale de celuici, des cellules cartilagineuses survivantes peuvent être mises en évidence grâce à l'autoradiographie au S35.
  相似文献   
83.
Yoshino O  Quail A  Oldmeadow C  Balogh ZJ 《Injury》2012,43(2):169-173
IntroductionThe importance of the abdominal wall characteristics in intraabdominal pressure (IAP), intraabdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are poorly understood. The applicability of laboratory research findings to human scenarios is unknown due to the potential differences in abdominal wall elastance (AWE) amongst species. The aims of the study are to describe the AWE curve in rabbits and to compare it to the available human data.Materials and methodsProspective experimental animal study in the setting of research laboratory. Male New Zealand White rabbits weighting 2.7 kg ± 0.1 kg, were anesthetized and the AWE was determined by infusion of lactated Ringer's solution into the peritoneal cavity whilst the IAP was measured. A meta-analysis of peer-reviewed studies was conducted to define human AWE.ResultsThe described AWE was lower in the rabbit than in humans. The function comparing human and rabbit was: loge human IAP = (0.58 loge rabbit IAP + 1.6).ConclusionsThe AWE can vary amongst species. This study determined the relationship to allow the comparison of rabbit and human IAP. The proposed mathematical function is important for the advancement of interpretation and understanding of animal research into IAH and ACS. We recommend developing model-specific functions comparing individual animal models’ IAP and that of humans.  相似文献   
84.

Purpose:

To identify and characterize sickle cell disease (SCD)‐related changes in the composition of mandibular bone marrow using qMRI relaxometry histograms.

Materials and Methods:

Thirteen SCD patients and 17 controls underwent brain MR imaging with the mixed turbo spin‐echo (TSE) pulse sequence at 1.5T. The mandible was manually segmented and divided into body, angle, ramus, and condyle. T1 and T2 histograms of each mandible were modeled with Gaussian functions. The relaxation time histogram peaks were calculated, and the number of monomodal versus bimodal curves was compared.

Results:

SCD patients exhibited monomodal distributions on both T1 and T2 histograms, consistent with a composition of predominantly red hematopoietic marrow. Eighty‐eight percent of mandibles in control subjects exhibited a bimodal distribution in T1 and all showed a bimodal distribution in T2, indicating mixed but predominantly yellow marrow composition. The second peak in control subjects was shorter in T1 and longer in T2, consistent with yellow marrow composition.

Conclusion:

Instead of physiological fatty replacement, SCD patients exhibit red marrow persistence in the mandible, likely due to the increased demand for hematopoiesis. This phenomenon can be manifested by a monomodal curve in both T1 and T2 relaxometric histograms. J. Magn. Reson. Imaging 2013;37:1182–1188. © 2012 Wiley Periodicals, Inc.  相似文献   
85.
86.
Enhanced expression of C chemokine lymphotactin in IgA nephropathy   总被引:6,自引:0,他引:6  
Ou ZL  Hotta O  Natori Y  Sugai H  Taguma Y  Natori Y 《Nephron》2002,91(2):262-269
Leukocyte accumulation in the kidney is observed in patients with IgA nephropathy. Chemokines are a large family of cytokines chemotactic for leukocytes and have been shown to be upregulated in renal diseases. We previously reported that the gene expression of lymphotactin, a sole member of C chemokine subfamily, is enhanced in an animal model of crescentic glomerulonephritis, but its expression in human renal diseases is totally unknown. In the present study, we investigated the expression of mRNAs of lymphotactin and some other chemokines in IgA nephropathy. The expression of mRNAs for three chemokines, lymphotactin, MCP-1, and MIP-1beta, in renal cortex was increased and the levels of lymphotactin and MCP-1 mRNAs were statistically higher in patients with glomerular crescents than in those without crescents. These levels also correlated with tubulointerstitial changes and urinary protein excretion. Glomerular levels of mRNAs for lymphotactin and MCP-1, but not MIP-1beta, were higher in IgA nephropathy than controls. By immunohistochemical analysis, lymphotactin was detected in tryptase-positive cells (putative mast cells) in the interstitial space. These results suggest that lymphotactin, as well as MCP-1, may contribute to leukocyte infiltration and disease progression in IgA nephropathy.  相似文献   
87.
A rare case of retroperitoneal bronchogenic cyst is presented. A 50-year-old man was referred to our hospital for an investigation of a retroperitoneal mass. Computed tomography and magnetic resonance imaging confirmed a retroperitoneal mass, about 4 cm in diameter, adjacent to the left kidney and spleen. On the basis of these imaging modalities, a definitive diagnosis of this mass could not be made. So, resection of the mass was performed. The removed mass was an unilocular cyst and filled with mucinous fluid. Histopathologically, the cyst wall was composed of a fibrovascular connective tissue containing mucus-secreting glands and cartilages and was lined by ciliated pseudostratified columnar epitherium. Thus, a diagnosis of bronchogenic cyst was made. Bronchogenic cysts are rare congenital anomalies of the primitive foregut and usually develop in the mediastinum and lung.  相似文献   
88.
Abstract. Background/Purpose: Although curative surgical resection provides the best chance of long-term survival for patients with intrahepatic cholangiocarcinoma, the presence of bile duct invasion decreases postoperative survival rates in patients with mass-forming intrahepatic cholangiocarcinoma. We carried out this study to determine a surgical strategy for patients with bile duct invasion of these tumors. Methods: Forty-one patients with mass-forming intrahepatic cholangiocarcinoma were classified as either having bile duct invasion (n= 26) or not having bile duct invasion (n= 15). Clinicopathologic findings, including postoperative outcomes, were compared between these two groups. Results: Perineural invasion, lymphatic invasion, and a positive resection margin were more frequent in patients with ductal invasion. Patients with ductal invasion had lower survival rates than those without ductal invasion. Conclusions: Intraoperative frozen section examination of the bile duct stump to confirm a clear resection margin is required in patients with mass-forming tumors. Resection of the extrahepatic bile duct should be considered when tumor cells are identified at the surgical margin of the resected bile duct. Received: October 30, 2001 / accepted: November 16, 2001  相似文献   
89.
Miura H  Taira O  Hiraguri S  Maeda J  Kato H 《Surgery today》2002,32(10):891-895
Squamous cell carcinoma of the breast is a rare type of cancer, the origin of which is still uncertain. We report a case of squamous cell carcinoma of the breast with a recurrent tumor that showed undifferentiated features. The patient was a 55-year-old woman who originally presented with a left breast mass in the upper outer quadrant. Echography showed a 46 × 29 × 23-mm mass with cavity formation, and aspiration cytology confirmed a diagnosis of squamous cell carcinoma. A modified radical mastectomy with level III lymph node dissection was performed. Pathologically, the tumor was composed of squamous cell carcinoma and noninvasive ductal carcinoma. A recurrent tumor showing undifferentiated features was detected in the left forechest 3 months after the operation, and tumorectomy with partial resection of the major and minor pectoralis muscles was performed. Despite intensive therapy including chemotherapy (CEF: cyclophosphamide, epirubicin, 5-fluorouracil) and irradiation (50 Gy), the patient died from pulmonary and skin metastases 20 months after her initial operation. The squamous cell carcinoma of the breast in this patient grew rapidly and her prognosis was poor. Immunohistochemical findings indicated the possibility that the squamous cell carcinoma developed from noninvasive ductal carcinoma of the comedo type, and that the undifferentiated cells from the site of recurrence developed from dedifferentiation of the squamous cell carcinoma. Received: August 10, 2001 / Accepted: March 5, 2002  相似文献   
90.
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   
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