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Biomedical subjects

N Uesugi

Publications and source records attributed to N Uesugi.

At least 19 recordsLinked to original sources

A novel endoscopic marker: safety experiments in the rat stomach.

BACKGROUND AND STUDY AIMS: The study aimed to assess a newly developed endoscopic marker designed to cause only minor inflammatory reactions. MATERIALS AND METHODS: Chitosan and carbon powder were used in the marker substance. The product was a viscoelastic solution, which was injected into the submucosa in rat stomach walls. The tissue reactions were then examined histopathologically. The structure of the injected marker substance was examined with electron microscopy into rat stomach walls. India ink, which is currently used as an endoscopic marker, served as the control. RESULTS: Histopathological examination showed that inflammatory reactions with the novel agent were remarkably mild in the rat organs, while submucosally applied india ink caused severe inflammation in situ. The electron-microscopic findings showed that the carbon particles used were completely spherical in shape and that the carbon in the marker substance was entrapped in the chitosan networks. The india ink was shown to consist of a mixture of fine carbon particles and adhesive additives. CONCLUSIONS: The chitosan-carbon solution appears to be a promising endoscopic marker substance, causing significantly reduced inflammation.

Animals↗

True carcinosarcoma of the esophagus.

Most esophageal carcinosarcomas are diagnosed as so-called carcinosarcoma, in which individual elements may be derived from a single common ancestor cell, and there have been a few reports describing true carcinosarcoma originating from two individual stem cells. We describe a case of esophageal carcinosarcoma exhibiting neoplastic osteoid formation. Immunoreactivity for vimentin and p53 was limited to only the sarcomatous component and was absent in the carcinomatous component. Furthermore, a point mutation in exon 7 of the p53 gene was observed only in the sarcomatous component. Both sarcoma and carcinoma cells distinctively metastasized to different lymph nodes. These observations led us to diagnose the esophageal tumor as a true carcinosarcoma.

Carcinosarcoma↗

Low-dose prednisolone ameliorates acute renal failure caused by cholesterol crystal embolism.

AIMS: The prognosis of renal cholesterol crystal embolism (CCE) is poor. Although various treatments for CCE have been attempted, there is no optimal therapy. We tested the effect of low-dose prednisolone (PS) on CCE-related acute renal failure (ARF). PATIENTS AND METHODS: 7 patients (mean age 69 years) diagnosed with CCE-related ARF were treated with oral PS at 15-20 mg/day for 2-4 weeks, which was then tapered at 5 mg/day over 2-4 weeks, followed by 5 mg/day maintenance dose. Recurrent ARF during PS tapering was treated with a larger dose of PS. RESULTS: Inciting factors were identified in four patients: coronary angiography (n=3) and cerebral angiography (n=1). On admission, serum creatinine (SCr) was 2.1 +/- 0.3 mg/dl (mean +/- SEM). SCr and eosinophil count before treatment were 4.2 +/- 0.4 mg/dl and 682 +/- 73/microl, respectively. PS therapy improved ARF in all cases at week 2 (SCr 3.8 +/- 0.5 mg/dl) parallel to a decrease in eosinophilia (116 +/- 30/microl), and at week 4 (3.1 +/- 0.4 mg/dl and 134 +/- 20/microl, respectively). At last follow-up, renal function was improved or maintained in 5 patients compared with that at week 4 post-treatment. One patient died of lung cancer. Another required LDL apheresis and hemodialysis but died due to CCE-related multi-organ failure. A third patient had recurrent ARF and was re-treated with a larger dose of PS, which resulted in an immediate decrease in SCr. However, the patient developed acute renal dysfunction due to congestive heart failure, and required hemodialysis. CONCLUSIONS: Low-dose PS improved CCE-related ARF, probably through amelioration of inflammatory reaction surrounding affected renal vessels.

Acute Kidney Injury↗

Frequent allelic imbalance at the ATM locus in DNA multiploid colorectal carcinomas.

DNA multiploidy may involve specific DNA ploidy states with respect to genetic alterations such as oncogenes, tumor suppressor gene mutation and microsatellite instability. To clarify the role of DNA multiploidy in colorectal cancer, we analysed allelic imbalance involving the ATM gene, localized to chromosome 11q22-23 and thought to be involved in genetic stability, in a series of multiploid colorectal carcinomas. In addition, p53 gene mutation (exons 5-8) and allelic imbalance at 11q24 loci distal to the ATM locus were also examined. The crypt isolation technique coupled with DNA cytometric sorting and polymerase chain reaction assay using 10 microsatellite markers tightly linked to the ATM gene were used to study ATM allelic imbalance in 55 colorectal carcinomas (15 diploid, 13 aneuploid, 27 multiploid). While allelic imbalance at the ATM locus was rarely observed in diploid and aneuploid carcinomas, multiploid carcinomas exhibited a high frequency of ATM allelic imbalance. In multiploid carcinoma samples, diploid subpopulations showed a smaller range of allelic imbalance at the loci tested compared to aneuploid subpopulations that demonstrated allelic imbalance over a relatively large region. Also, the frequency of AI at 11q24 showed a similar tendency to that at the ATM locus for each DNA ploidy state. An association between p53 gene mutation and ATM allelic imbalance in multiploid carcinoma was also observed. Our results suggest that ATM allelic imbalance and p53 gene mutations occur during the progression from diploid to aneuploid cell populations in multiploid colorectal carcinomas.

Allelic Imbalance↗

Glycoxidation and lipid peroxidation of low-density lipoprotein can synergistically enhance atherogenesis.

OBJECTIVE: The purpose of this study was to clarify the role of glycoxidation and lipid peroxidation of low-density lipoprotein (LDL) in atherogenesis. METHODS AND RESULTS: We examined the formation of N(epsilon)-(carboxymethyl) lysine (CML), a glycoxidation product, and malondialdehyde (MDA), a lipid peroxidation product, in vitro and their co-localization in human atherosclerotic lesions. Immunochemical analysis revealed that CML was formed in a time-dependent manner by human LDL incubated with copper ions and glucose, i.e. an in vitro model of glycoxidation of LDL. When LDL was exposed to copper ions alone, a small amount of CML was formed, however this was significantly less in oxidized LDL than glycoxidative LDL. In contrast, MDA formation was observed in both oxidation and glycoxidation of LDL, but not in glycation of LDL. Hexitol-lysine (HL), an Amadori product, was formed by both glycation and glycoxidation of LDL, but not by oxidation of LDL. Immunohistochemical analysis showed that CML and MDA accumulated mainly in macrophage/foam cells, while pyrraline, a non-oxidative product of glycation, and apolipoprotein B were localized in the extracellular matrix in atherosclerotic lesions. Atheromas were positive for CML and MDA, but negative for pyrraline. Macrophage/foam cells in atherosclerotic lesions exhibited co-localization of macrophage scavenger receptor-A with CML and MDA, but not with pyrraline. CONCLUSION: Our results suggest that glycoxidation and lipid peroxidation of LDL synergistically promote the development of atherosclerotic lesions through interaction with macrophage scavenger receptor-A.

Adult↗

Infrequent microsatellite instability in biliary tract cancer.

BACKGROUND AND OBJECTIVES: Microsatellite instability (MSI) has been reported in several tumors. However, few reports are available concerning MSI in biliary tract cancers. We investigated MSI and allelic loss at the hMLH1 and hMSH2 gene loci in biliary tract cancers. METHODS: We analyzed microsatellite alterations using 7 microsatellite markers in 38 cases of extrahepatic bile duct (EHBD) cancer and 16 cases of ampullary cancer using polymerase chain reaction and an automated fluorescent DNA sequencer. RESULTS: A MSI prevalence of 13.2% (5/38) was observed for EHBD cancer and a prevalence of 12.5% (2/16) was observed for ampullary cancer. Loss of heterozygosity at the hMLH1 and hMSH2 gene loci were observed in 4% (1/25 informative cases) and 6.1% (2/33) of EHBD cancer cases, respectively; and in 11.1% (1/9) and 8.3% (1/12) of ampullary cancer cases, respectively. The cumulative survival rate of patients with MSI was significantly better than that of patients without MSI in EHBD cancer. However, MSI was not an independent prognostic factor. CONCLUSIONS: Our results suggest that genetic defects in the DNA mismatch repair system and MSI do not play an important role in the majority of biliary tract cancers.

Adaptor Proteins, Signal Transducing↗

Sebaceous gland metaplasia in intraductal papilloma of the breast.

We report here the first case of sebaceous gland metaplasia arising within an intraductal papilloma of the breast of a 70-year-old female. Several lobules and nests composed of clear cells closely resembling sebaceous glands of the skin were discovered within an intraductal papilloma of the breast. Squamous metaplasia was also noted in certain areas of the tumor. Immunohistochemically, the cells of the lobules and nests stained positively for monoclonal antibodies anti-cytokeratin 14 and epithelial membrane antigen. This study confirms a novel type of metaplasia of the breast.

Aged↗

Chemoradiotherapy followed by surgery for thoracic esophageal cancer potentially or actually involving adjacent organs.

The objective of this study was to evaluate the therapeutic usefulness of chemoradiotherapy (CRT) followed by surgery in patients with clinically T4 (cT4) esophageal cancer involving adjacent organs such as the trachea, main bronchi, and large vessels. Thirty-seven patients with cT4 squamous cell carcinoma of the thoracic esophagus were enrolled in this study. The CRT regimen comprised cisplatin (70 mg/m2) on day 1, 5-fluorouracil (700 mg/m2) on days 1-4 and external irradiation (200 cGy/day, total 30 Gy) on either days 8-26 (sequential schedule, n=15) or days 1-19 (concurrent schedule, n022). Two courses of CRT were given. The results of CRT were complete response in nine patients, partial response in 19, no change in three (minor response in two), and progressive disease in six patients. The median response duration in all responders was 172 days (range: 56-2469, n=19). After CRT, 13 patients received surgery. In 12 of these patients, tumors were completely resected. Histopathologic examination of the resected specimen revealed a discrepancy between clinical response and histopathologic effect. The median duration of survival and the 1-, 2- and 5-year survival rates were 304 days (84-3155), 45%, 35% and 23% in all patients, respectively, 866 days (190-3155), 83%, 83% and 57% in the 13 patients whose tumors were resected, and 187 days (84--2630), 25%, 5% and 5% in the 24 patients whose tumors were not resected. Grade 3 toxicity, especially hematological reactions, was noted in 13.5% (5/37) of the patients. There was one toxicity-related death (sepsis). A good outcome may be obtained with CRT, followed by surgery when feasible. However, CRT can cause toxic reactions, and close monitoring of patients is required.

Aged↗

Glycoxidation-modified macrophages and lipid peroxidation products are associated with the progression of human diabetic nephropathy.

The aim of this study is to investigate the role of glomerular macrophages activated by glycoxidation and lipid peroxidation products in the progression of glomerular lesions in diabetic nephropathy. Renal biopsy samples from 43 patients with diabetes (age, 54 +/- 14 years) and 10 control cases were immunohistochemically examined for the expression of carboxymethyllysine (CML), a representative glycoxidative product; oxidized phosphatidylcholine (Ox-PC), a representative lipid peroxidation product; leukocyte common antigen (LCA); CD68; and macrophage scavenger receptor (MSR) class A. The severity of the diffuse lesions in each glomerulus was histologically graded from 0 to IV. When grade II and III lesions had Kimmelstiel-Wilson (KW) nodules, they were placed in a new category called grade III with KW nodules. The number of cells positive for CML, Ox-PC, LCA, CD68, and MSR was compared in different grades. The number of macrophages per glomerulus increased with the glomerular lesion grade and was highest in grade III with KW nodules. Conversely, the number of lymphocytes did not parallel the grade of glomerular lesions. Almost 50% of macrophages contained CML, and more than 40% of those were observed in exudative lesions, tuft adhesions, and at the periphery of KW nodules. Ox-PC accumulated in 50% of CML-positive macrophages, which coexpress MSR. Macrophages positive for CML and Ox-PC increased with the grade. Glomerular macrophages may be activated by glycoxidative and lipid peroxidation products through MSR and may have a role in the development of human diabetic glomerulosclerosis.

Adolescent↗

Prognosis of renal amyloidosis: a clinicopathological study using cluster analysis.

Progression of renal amyloidosis is associated with severe proteinuria or nephrotic syndrome, and various mechanisms have been postulated to explain these complications. We studied the acceleration of proteinuria and reduced renal function by cluster analysis using clinical parameters, renal histological findings, type of renal amyloidosis and follow-up data. We divided 97 cases into three groups of renal amyloidosis. Accelerated progression correlated with serum creatinine (s-Cr) levels at renal biopsy and histological grade of renal damage by amyloid deposition (p < 0.0001). The most influential prognostic factors (s-Cr level > or =2.0 mg/dl) were tubulointerstitial and vascular damage induced by amyloid deposition at biopsy (odds ratio 96.9 and 69.2, respectively). In addition, we found amyloidosis type amyloid associated (AA) correlated with more amyloid-mediated vascular and tubulointerstitial damage than amyloidosis type amyloid light chain (AL) (p < 0.001, p < 0.01, respectively). Proteinuria and nephrotic syndrome were more severe in cases of amyloidosis AL than in amyloidosis AA (p = 0.076). In conclusion, less tubulointerstitial and vascular damage was caused by amyloid deposition; this was slowly progressive. Amyloid AA was detected in tubulointerstitial tissue and vessels more frequently than amyloid AL. Heavy proteinuria and/or nephrosis were not indicators of rapid progression.

Adult↗

Obesity associated with hypertension or hyperlipidemia accelerates renal damage.

Obesity is known as a risk factor for nephropathy, especially nephrotic syndrome and focal segmental glomerulosclerosis, and can aggravate renal dysfunction. However, whether these changes are caused by obesity itself or by the associated hypertension (HT) and hyperlipidemia (HC) remains unclear at present. We investigated the influence of HT and HC in obesity on glomerular morphometry. The study included cases with obesity alone (O, body mass index more than 25 kg/m(2), n = 16), O+HC (n = 8), O+HT (n = 17), HC (n = 10) alone, HT (n = 7) alone, and normal subjects (N, n = 11). Renal biopsies were examined and the glomerular diameter, and length and diameter of the glomerular capillary loop were determined using image analysis software. Clinically related data were obtained from medical records at the time of biopsy. Obesity was associated with dilatation of glomerular diameter due to glomerular loop elongation. However, end-stage renal disease (ESRD) was not noted in patients with obesity only. In contrast, ESRD requiring hemodialysis was noted in group O+HT within a 7.7-year follow-up period. Furthermore, enlargement of loop diameter was noted in group O+HC, but not in HC alone. These results suggest that obesity alone may not result in glomerular hyperfiltration or renal dysfunction, but obesity associated with hypertension or hyperlipidemia may accelerate renal damage.

Adolescent↗

Benign nephrosclerosis: incidence, morphology and prognosis.

AIMS: Study of benign nephrosclerosis (BNS) is often mixed up with IgA nephritis (IgAN) associated with hypertension or thin basement membrane disease (TBMD). Here we examined the clinicopathological features, incidences and prognosis of decompensated BNS. MATERIALS AND METHODS: BNS was identified in 590 (8.3%) adult cases among 7,108 renal biopsies of a mean age of 56.5 years (male: female ratio = 2.5:1). The post-biopsy follow-up period ranged from 3 to 22 years (10.1 +/- 4.6 years). RESULTS: Patients with progressive BNS were more likely to develop end-stage renal disease within 5 years of biopsy. Poor prognostic factors included poor or no control of arterial blood pressure by anti-hypertensive drugs, global glomerulosclerosis (GS) (> or = 41%) at biopsy, presence of collapsed glomeruli and/or segmented or semi-global GS. Tubulointerstitial damage, glomerular hypertrophy and loop dilatation were secondary to GS. Gender, duration of HT and onset of HT to biopsy were not significant factors. CONCLUSION: GS in BNS is due to ischemia induced by luminal narrowing or obstruction of preglomerular vessels, and glomerular HT due to loss of autoregulation in preglomerular vessels (irregularly shaped atrophic or segmented medial smooth muscle cells, with expansion of extracellular matrix with or without fibrous intimal thickening). GS resulted in luminal dilatation. Both pathological changes affecting the glomerulus may occur in the same kidney and different nephron units.

Female↗

Genetic alterations in DNA diploid, aneuploid and multiploid colorectal carcinomas identified by the crypt isolation technique.

Loss of heterozygosity (LOH) and microsatellite instability (MSI) commonly occur in colorectal carcinomas. However, the role of these genetic alterations in determining DNA ploidy status of tumors (diploid, aneuploid and multiploid) remains unclear. In the present study, we attempted to clarify the relationship between genetic alterations and DNA ploidy status. Crypt isolation coupled with DNA cytometric sorting and polymerase chain reaction assay (17 microsatellite markers) were used to study allelic losses and MSI in 59 colorectal carcinomas (diploid, 15; aneuploid, 10 and multiploid, 34). Of the 15 diploid carcinomas, 6 exhibited MSI in which allelic losses were rarely found. The other 9 diploid tumors mostly exhibited allelic losses, but none displayed MSI status. Whereas allelic losses frequently occurred in the aneuploid carcinomas and the aneuploid populations of multiploid carcinomas, they were rarely detected in the diploid populations of multiploid carcinomas. MSI status was not observed in aneuploid carcinomas nor in either population of multiploid carcinomas. Although multiploid carcinomas genetically resemble aneuploid carcinomas in the expression of the severe LOH phenotype, the genetic alterations seen in the diploid populations of multiploid carcinomas may differ from those of diploid carcinomas. Furthermore, all diploid, aneuploid and both the diploid and aneuploid fractions of the multiploid tumors that were non-MSI exhibited a high rate of LOH, suggesting that LOH is independent of the tumor's ploidy status.

Adenocarcinoma↗

DNA mapping of gastric cancers using flow cytometric analysis.

Although numerous studies of gastric cancers on DNA ploidy have been reported, differences in the degree of aneuploidy (DNA index, DI) during progression have not been identified. We attempted to chart the differences in DIs during progression to clarify the role of aneuploidy in gastric cancers. We classified the gastric cancers examined into intestinal (n = 88) and diffuse (n = 48) types, and then analyzed 136 gastric cancers (intramucosal cancer, 42; submucosal cancer, 39; advanced cancer, 55) by flow cytometry using multiple sampling. In addition, we examined the DNA ploidy pattern of mucosal and submucosal lesions using the same submucosal cancers to study the tumor progression in individual cancers. Intratumoral DNA differences in DNA ploidy were observed in both types of gastric cancers. In intestinal-type cancers, multiple subclones indicated by a different DI occurred during the early stage of gastric cancers, whereas in diffuse-type cancers, multiple subclones were found primarily in advanced cancers. Although the DI varied widely in early intestinal-type cancers between 1.0 and 2.0, in early diffuse-type cancers, the DI tended to be less than 1.2. However, in advanced stage gastric cancers, the DI distribution was similar for both histological types. In intestinal-type cancers, high DI (>1.3) aneuploidy was frequently found in mucosal lesions. In contrast, only low DI (<1.2) aneuploid clones were observed in mucosal lesions of diffuse-type cancers. The present results suggest that high DI aneuploid tumor clones in intramucosal cancers acquire invasive ability when they progress to submucosal cancers, whereas DNA aneuploidy itself plays an important role in submucosal invasion of diffuse-type cancers.

Adult↗

Aberrations of the K-ras, p53, and APC genes in extrahepatic bile duct cancer.

BACKGROUND AND OBJECTIVES: The genetic alterations involved in extrahepatic bile duct (EHBD) cancer are poorly understood. Our aim was to identify aberrations of the K-ras, p53, and APC genes in EHBD cancer. METHODS: We investigated aberrations of these genes in 52 EHBD cancers using polymerase chain reaction (PCR) single-strand conformation polymorphism analysis, followed by direct sequence determination and a PCR restriction fragment length polymorphism assay. RESULTS: The K-ras, p53, and APC genes were mutated in 9.6%, 32.7%, and 0% of EHBD cancers, respectively. Loss of heterozygosity at the p53 and APC gene loci was identified in 15.6% and 38.5% of EHBD cancers, respectively. CONCLUSIONS: Our results suggest that an unknown suppressor gene on 5q other than the APC gene may be responsible for EHBD cancer.

Aged↗