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81.
Biochemical characterisation of para-aminophenol-induced nephrotoxic lesions in the F344 rat 总被引:5,自引:0,他引:5
Kevin P. R. Gartland Frank W. Bonner John A. Timbrell Jeremy K. Nicholson 《Archives of toxicology》1989,63(2):97-106
The acute biochemical effects of the nephrotoxin p-aminophenol (PAP) were studied in detail using a combination of conventional bioanalytical and 1H-NMR spectroscopic methods. Dosing PAP (25–100 mg/kg) to male F344 rats resulted in a dose-related proximal nephropathy with consequent elevations in urinary enzymes, glucose, and urine total protein as shown by conventional methodology. 1H-NMR spectroscopy at 400 MHz of urine from PAP-treated rats also revealed a characteristic glycosuria, with concomitant amino aciduria. The increased excretion of these compounds indicates functional defects in the proximal tubule and reduced solute reabsorption efficiency. In addition, 1H-NMR urinalysis and conventional enzymatic analysis showed a dose-related lactic aciduria. Other changes detected by 1H-NMR included a dose-related reduction in the excretion of citrate (confirmed by a conventional biochemical method) and an increase in the excretion of acetate. The degree of abnormalities shown by 1H-NMR urinalysis agreed well with histopathological observations and conventional biochemical indices of nephrotoxicity. 1H-NMR urinalysis therefore serves to highlight changes in the excretion of low MW urine components not routinely studied by conventional biochemical analysis.Abbreviations ALP
alkaline phosphatase
- APAP
paracetamol
- BUN
blood urea nitrogen
- GFR
glomerular filtration rate
- GOT
glutamate oxaloacetate transaminase
- LAP
leucine aminopeptidase
- LDH
lactate dehydrogenase
- MW
molecular weight
- NAG
N-acetyl--D-glucosaminidase
- PAP
p-aminophenol
- ppm
parts per million
- TMAO
trimethylamine N-oxide
- UFR
urine flow rate 相似文献
82.
Lymphoepithelioma-like carcinoma of the bladder: three cases with clinicopathological and p53 protein expression study 总被引:12,自引:0,他引:12
Izquierdo-García FM García-Díez F Fernández I Pérez-Rosado A Sáez A Suárez-Vilela D Guerreiro-González R Benéitez-Alvarez M 《Virchows Archiv : an international journal of pathology》2004,444(5):420-425
Lymphoepithelioma-like carcinoma of the bladder is an uncommon neoplasm, of which 49 cases have been described in the English literature, none of which has been studied for p53 protein expression. We studied three muscle-infiltrating cases of this tumor using immunohistochemical, in situ hybridization and polymerase chain reaction (PCR) methods. The three cases were positive for epithelial markers and negative for lymphoid antigens in the tumoral syncytial areas. The intensive infiltrate of small cells was negative for epithelial and positive for lymphoid markers. This population was mainly made up of cytotoxic T-lymphocytes, positive for TIA-1. p53 protein was intensely positive in more than 90% of the epithelial component nuclei, being negative in the lymphoid cells. PCR study did not show mutations on p53. Both lymphocytes and epithelium were negative for Epstein–Barr virus markers, such as the latent membrane protein and EBER (Epstein–Barr-encoded RNA). The prognosis was very good after radiotherapy and chemotherapy treatment, preserving the bladder despite the muscle infiltration. The presence of an intense cytotoxic T-lymphocyte population may be related to this good prognosis. Both aspects, p53 protein status and T-lymphoid population, had never been studied before in bladder lymphoepithelioma-like carcinoma. 相似文献
83.
Mr N. Ishikawa S. Suda T. Sasaki T. Yamanishi H. Hosaka K. Yasuda H. Ito 《Medical & biological engineering & computing》1998,36(6):704-710
A system composed of a functional continuous magnetic stimulator (FCMS) and a saddle-type coil has been developed for non-invasive
treatment of urinary incontinence, especially stress incontinence and urge incontinence. The FCMS conditions were as follows:
2 kW maximum electrical power consumption, 800 V maximum capacitor voltage, 720 μs pulsewidth (180 μs rise time), and 5–30
Hz frequency. A frequency between 5 and 10 Hz is used to treat urge incontinence and a frequency between 25 Hz and 30 Hz is
used to treat urge incontinence. The coil (120 mm long, 90 mm wide and 50 mm thick) fits the most suitable region for this
treatment, the region from the anus to the perineum. The coil is cooled to maintain a coil temperature between 20 and 25°C
so that it can be used efficiently and safely. In experiments with anaesthetised dogs, it was confirmed that the urethral
pressure increased when the circumference of the perineum received continuous magnetic stimulation of 720 μs pulsewidth (180
μs rise time), 10Hz frequency and about 520 V capacitor voltage. This result suggests that magnetic stimulation can be effective
as a urinary incontinence therapy. 相似文献
84.
P. Vogelaere G. Savourey G. Deklunder J. Lecroart M. Brasseur S. Bekaert J. Bittel 《European journal of applied physiology》1992,64(3):244-249
Summary Classically, cold induced plasma volume reduction is explained by an increased diuresis which is generated by an inhibition of antidiuretic hormone release. However, most of the haemoconcentration appears to be reversible during rewarming. This observation weakens the former statement. The aim of this study was to clarify the mechanisms involved in the reversal of the cold induced haemoconcentration. Six young males, resting in a dorsal reclining position, were exposed successively to a thermoneutral environment (30 min), a cold environment (1° C; cold) or thermoneutrality (control) for 120 min, and during a 60-min recovery period in thermoneutral conditions. During cold stress, a reduction of 15% (i.e. 510 ml) of the plasma volume was observed, and osmolality was unchanged. After the 60-min recovery under thermoneutral conditions, plasma volume variation between the Cold and the Control experiments was reduced and reached 3% (i.e. 100 ml). This volume equalled the increased amount of urine production observed during the cold stress experiment. Haemoconcentration cannot be explained by increased urinary water loss (± 100 ml) alone. Therefore a transient shift of plasma water from vascular to interstitial spaces, due to an increase of blood pressure, could be involved in the reduction of plasma volume. 相似文献
85.
Loss of heterozygosity on chromosomes 3p,8p,9p and 17p in the progression of squamous cell carcinoma of the larynx 总被引:4,自引:0,他引:4
Yoo WJ Cho SH Lee YS Park GS Kim MS Kim BK Park WS Lee JY Kang CS 《Journal of Korean medical science》2004,19(3):345-351
Previous molecular genetic studies of laryngeal squamous cell carcinoma (SCC)have shown certain chromosomal regions with recurring alterations. But studies of sequential molecular alterations and genetic progression model of laryngeal SCC have not been clearly defined. To identify the chromosomal alterations associated with the carcinogenesis of laryngeal SCC, we analyzed genomic DNA from microdissected squamous metaplasia, squamous dysplasia, invasive SCC, and metastatic carcinoma samples from 22 laryngeal SCC patients for loss of heterozygosity (LOH) at microsatellite loci. Ten microsatellite markers on chromosome 3p, 8p, 9p, and 17p were used. LOH at 9p21 was observed in the all stages including squamous metaplasia, squamous dysplasia, invasive SCC and metastatic carcinoma. LOH at 17p13.1, 3p25 and 3p14.2 was observed from the squamous dysplasia, invasive SCC and metastatic carcinoma. LOH at 8p21.3-p22 was observed mainly from the invasive SCC and metastatic carcinoma. The results suggest that 9p21 in the early event, 17p13.1, 3p25 and 3p14.2 in the intermediate event and 8p21.3- p22 in the late event may be involved in the laryngeal carcinogenesis. 相似文献
86.
Christoph Olbricht June Mason Toshikazu Takabatake Gero Hohlbrugger Klaus Thurau Sigrid Pätz 《Pflügers Archiv : European journal of physiology》1977,372(3):251-258
Summary Experiments were designed to determine whether leakage of substances across the tubular epithelium, which are impermeant in the normal kidney, falsifies the measurement of glomerular filtration rate in acute renal failure. Permeability to those substances most commonly used for filtration rate determination, polyfructosan, inulin and ferrocyanide, was estimated by measuring their recoveries following perfusion through various nephron segments in haeme pigment, ischaemic and nephrotoxic models of actue renal failure. Late proximal recovery of14C ferrocyanide was only marginally decreased compared to controls, by a maximum of 6%. Distal recovery of polyfructosan,14C and3H inulin were depressed somewhat more, by a maximum of 11%. Urinary recovery of14C inulin was reduced by only 15% in kidneys showing severely restricted renal function. It is concluded that tubular leakage is not a feature of significance in the early phase of moderate acute renal failure, that ferrocyanide and inulin are reliable markers for the determination of nephron filtration rate and water reabsorption, and that the reduction in whole kidney inulin or polyfructosan clearance reflects primarily a reduction in glomerular filtration rate. 相似文献
87.
目的:探讨单发性和多发性浅表膀胱移行细胞癌组织中血管内皮生长因子(VEGF)的表达及意义。方法:采用免疫组化方法对60例浅表膀胱移行细胞癌组织及10例正常膀胱组织进行血管内皮生长因子(VEGF)的检测,观察单发性和多发性浅表膀胱移行细胞癌组织中VEGF表达的关系。结果:多发性浅表膀胱移行细胞癌VEGF的高表达明显高于单发者的高表达;VEGF高表达的浅表膀胱移行细胞癌的患者的复发率明显高于低表达者的复发率。结论:VEGF表达的高低与浅表膀胱移行细胞癌的生物学行为有关。 相似文献
88.
Irving Dardick Vienna L. Ostrynski J. Kenneth Ekem Richard Leung Aileen P. Burford-Mason 《Virchows Archiv : an international journal of pathology》1992,421(2):95-104
Summary The degree and range of differentiation of the cells referred to as myoepithelial-like in pleomorphic adenomas and the tumour cells of myoepitheliomas are not definitely established. This type of information is critical for establishing reliable diagnostic criteria, such as expression of muscle-specific actin and ultrastructural identification of myofilaments, in these and other salivary gland tumours. Pleomorphic adenomas (18) and myoepitheliomas (5), of which 10 cases were fixed only in formalin and 13 cases where tissues were fixed in both formalin and methanol/acetic acid, were studied. Each tumour and normal accompanying parotid was immunostained with two monoclonal antibodies for smooth muscle actin, HHF35 and MSA. Staining of myoepithelial cells was absent in certain samples of normal gland with both HHF35 (15%) and MSA (69%) when formalin-fixed tissue was used. Using formalin-fixed tissue from 15 pleomorphic adenomas/myoepitheliomas, 2 (14%) had focal positivity with HHF35, while 8 cases (57%) were positive with MSA. However, a certain degree of false positivity was suspected since in samples of normal parotid, both acinar and duct cells were frequently stained, particularly with MSA. With methanol/ acetic acid-fixed tissue only 4 of 13 cases (31%) were positive with either MSA or HHF35 and 2 of these only had a minor proportion of the tumour cells expressing muscle-specific actin. Using alcohol-fixed tissue, myoepithelial cells were strongly stained in all examples of normal parotid gland with both anti-actin antibodies. In 5 cases examined by electron microscopy, there was no apparent correlation between immunohistochemical results and the presence or absence of cytoplasmic filament accumulation. The results indicate considerable tumour cell heterogeneity in muscle-specific actin expression and suggest that non-luminal cells in pleomorphic adenomas and the tumour cells in myoepitheliomas may differentiate as classical myoepithelial cells, as partially differentiated (i.e. modified myoepithelial cells) or as the counterpart of basal cells present in the intra- and interlobular ducts of normal salivary gland. 相似文献
89.
David W. Ingersoll George Bobotas Ching-Tse Lee Aaron Lukton 《Physiology & behavior》1982,29(5):789-793
The present study was designed to investigate the chemical properties of the aggression-promoting cues present in bladder urine of male mice. The results of the first experiment confirmed earlier work by demonstrating the presence of an aggression-promoting chemosignal in bladder urine. In Experiment 2, behavioral assays were separately performed on the organic and aqueous layers of bladder urine obtained by repeated dichloromethane extractions. Only the combined organic layers of the initial three extractions demonstrated behavioral activity. A fourth extraction showed no behavioral activity for both organic and aqueous layers. However, the findings of Experiment 3 showed that incubation of the aqueous layer from the third CH2Cl2 extraction in β-glucuronidase can free additional aggression-promoting cues into a subsequent CH2Cl2 extraction. It is concluded that two forms of the aggression-promoting chemosignal are present in bladder urine. One is lipophilic and behaviorally active, whereas the other is conjugated, possessing latent chemosignal properties. 相似文献
90.
Sinonasal teratocarcinosarcoma: ultrastructural and immunohistochemical evidence of neuroectodermal origin 总被引:4,自引:0,他引:4
The authors report a case of sinonasal teratocarcinosarcoma in a 37-year-old man, which was located in the anterior skull base and extended to the right nasal cavity and paranasal sinuses. The tumor was surgically resected twice, but it could not be removed completely. Microscopically, it was mainly composed of primitive cell nests within a moderately cellular stroma. The components of squamous cell epithelia with focal teratoid appearance and adenocarcinomatous differentiation were observed. There were many rhabdomyoblasts scattered in the nests and stroma. Ultrastructurally, the primitive cells had many neural processes with parallel microtubules, resembling olfactory neuroblastoma. Rhabdomyoblasts showed various degrees of skeletal muscle differentiation. Some of the stromal spindle cells had actin filaments with dense patches and dense core granules. Immunohistochemically, the primitive cells were positive for epithelial markers, neuron-specific enolase, synaptophysin, and myogenic regulatory proteins. The rhabdomyoblasts showed immunoreactivity for myoid markers, cytokeratin, epithelial membrane antigen, and synaptophysin. Most of the stromal spindle cells were positive for smooth muscle actin, neuron-specific enolase and synaptophysin. The immunohistochemical and ultrastructural findings suggest that primitive cells had the most primitive phenotype of placodes, and support the possibility that sinonasal teratocarcinosarcoma is essentially a neuroectodermal tumor with divergent differentiation. 相似文献