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Lysyl oxidase-like protein 2 (LOXL2) modulates barrier function in cholangiocytes in cholestasis. J Hepatol 2018; 69:368-377. [PMID: 29709678 DOI: 10.1016/j.jhep.2018.04.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Revised: 04/03/2018] [Accepted: 04/08/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS The lysyl oxidase-like protein 2 (LOXL2) promotes stabilization of the extracellular matrix, chemotaxis, cell growth and cell mobility. We aimed to (i) identify stimuli of LOXL2 in cholangiopathies, (ii) characterize the effects of LOXL2 on biliary epithelial cells' (BECs) barrier function, (iii) compare LOXL2 expression in primary sclerosing cholangitis (PSC), primary biliary cholangitis, and disease controls, and (iv) to determine LOXL2 expression and its cellular sources in four mouse models of cholangiopathies. METHODS Cultured murine BECs were challenged with well-known triggers of cellular senescence, hypoxia, phospholipid-deficient Abcb4-/- mouse bile and chenodeoxycholic acid and investigated for LOXL2, SNAIL1 and E-cadherin expression and transepithelial electrical resistance with and without LOX-inhibition. In vivo, LOXL2 expression was studied in PSC livers, and controls and mouse models. We compared LOXL2 serum levels in patients with PSC, secondary SC, primary biliary cholangitis, and controls. RESULTS Cellular senescence, hypoxia, Abcb4-/- bile and chenodeoxycholic acid induced LOXL2 and SNAIL1 expression, repressed E-cadherin expression, and significantly reduced transepithelial electrical resistance in BECs. Notably, all of the pathological changes could be recovered via pharmacological LOX-inhibition. Mouse models showed induced LOXL2 expression in the portal region and in association with ductular reaction. LOXL2 serum levels were significantly elevated in patients with cholangiopathies. In PSC, LOXL2 expression was located to characteristic periductal onion skin-type fibrosis, ductular reaction, Kupffer cells, and fibrotic septa. Importantly, in PSC, LOXL2 overexpression was paralleled by E-cadherin loss in BECs from medium-sized bile ducts. CONCLUSIONS Reactive BECs produce LOXL2, resulting in increased tight junction permeability, which can be ameliorated by pharmacological LOX-inhibition in vitro. Reactive BECs, portal myofibroblasts, and Kupffer cells are the main sources of LOXL2 in cholangiopathies. LAY SUMMARY In this study, we investigate the role of lysyl oxidase-like protein 2 (LOXL2), an enzyme pivotal in the development of organ fibrosis, in the pathogenesis of cholangiopathies (diseases of bile ducts), such as primary sclerosing cholangitis. We found LOXL2 to be expressed in association with bile duct epithelial injury and uncovered mechanisms for its upregulation and the subsequent effects in vitro and in vivo. Our findings support testing of anti-LOXL2 treatment strategies for patients with primary sclerosing cholangitis.
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Pancreas transplantation with enteroanastomosis to native duodenum poses technical challenges--but offers improved endoscopic access for scheduled biopsies and therapeutic interventions. Am J Transplant 2015; 15:242-50. [PMID: 25394773 DOI: 10.1111/ajt.12953] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 07/02/2014] [Accepted: 07/22/2014] [Indexed: 01/25/2023]
Abstract
To facilitate endoscopic access for rejection surveillance and stenting of the pancreas, we have abandoned the duodenojejunostomy (DJ) in favor of duodenoduodenostomy (DD) in pancreas transplantation (PTx). From September 2012 to September 2013 we performed 40 PTx with DD; 20 solitary-PTx (S-PTx) and 20 simultaneous pancreas and kidney transplantation (SPK). We compared the outcomes with results from 40 PTx-DJ (10 S-PTx and 30 SPK) from the preceding era. The DD-enteroanastomoses were performed successfully. Endoscopic pancreas biopsies (endoscopic ultrasound examination [EUS]) yielded representative material in half of the cases. One exocrine fistula was treated by endoscopic stenting. PTxs-DD were associated with a higher rate of thrombosis compared to PTx-DJ (23% vs. 5%) and reoperations (48% vs. 30%), as well as inferior graft survival (80% vs. 88%). Time on waiting list, HLA A + B mismatches and reoperations were associated with graft loss. Only recipient age remained an independent predictor of patient death in multivariate analysis. PTx-DD showed a higher rate of thrombosis and inferior results, but facilitated a protocol biopsy program by EUS that was feasible and safe. Given that technical difficulties can be solved, the improved endoscopic access might confer long-term benefits, yet this remains to be proven.
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Molecular signatures of mRNAs and miRNAs as prognostic biomarkers in pancreatobiliary and intestinal types of periampullary adenocarcinomas. Mol Oncol 2014; 9:758-71. [PMID: 25579086 DOI: 10.1016/j.molonc.2014.12.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 12/02/2014] [Accepted: 12/08/2014] [Indexed: 02/08/2023] Open
Abstract
Periampullary adenocarcinomas include four anatomical sites of origin (the pancreatic duct, bile duct, ampulla and duodenum) and most of them fall into two histological subgroups (pancreatobiliary and intestinal). Determining the exact origin of the tumor is sometimes difficult, due to overlapping histopathological characteristics. The prognosis depends on the histological subtype, as well as on the anatomical site of origin, the former being the more important. The molecular basis for these differences in prognosis is poorly understood. Whole-genome analyses were used to investigate the association between molecular tumor profiles, pathogenesis and prognosis. A total of 85 periampullary adenocarcinomas were characterized by mRNA and miRNA expressions profiling. Molecular profiles of the tumors from the different anatomical sites of origin as well as of the different histological subtypes were compared. Differentially expressed mRNAs and miRNAs between the two histopathological subtypes were linked to specific molecular pathways. Six miRNA families were downregulated and four were upregulated in the pancreatobiliary type as compared to the intestinal type (P < 0.05). miRNAs and mRNAs associated with improved overall and recurrence free survival for the two histopathological subtypes were identified. For the pancreatobiliary type the genes ATM, PTEN, RB1 and the miRNAs miR-592 and miR-497, and for the intestinal type the genes PDPK1, PIK3R2, G6PC and the miRNAs miR-127-3p, miR-377* were linked to enriched pathways and identified as prognostic markers. The molecular signatures identified may in the future guide the clinicians in the therapeutic decision making to an individualized treatment, if confirmed in other larger datasets.
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Liver fibrosis progression at autopsy in injecting drug users infected by hepatitis C: a longitudinal long-term cohort study. J Hepatol 2014; 60:260-6. [PMID: 24096048 DOI: 10.1016/j.jhep.2013.09.022] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 09/24/2013] [Accepted: 09/26/2013] [Indexed: 12/15/2022]
Abstract
BACKGROUND & AIMS There is a paucity of unbiased data on the natural history of hepatitis C virus (HCV) infection in injecting drug users (IDUs). The purpose of this study was to assess the risk of developing advanced fibrosis associated with chronic hepatitis C (CHC) infection among injecting drug users (IDUs) who underwent an autopsy. METHODS A longitudinal cohort design was applied, in which the stage of liver fibrosis in anti-HCV positive IDUs with or without chronic HCV infection was assessed in liver tissue from autopsies performed up to 35 years after HCV exposure. The cohort originated from 864 IDUs consecutively admitted for drug abuse treatment 1970-1984. Stored sera, mostly drawn at the time of admission for drug treatment, were available in 635 subjects. 220 out of 523 anti-HCV positive subjects had died before 2009. Liver tissue from autopsies was available from 102/220 subjects, of which 61 were HCV RNA positive. Liver sections were classified according to METAVIR scores for fibrosis. Two pathologists, both blinded for serologic results, scored sections of liver tissue. RESULTS Among HCV RNA positive subjects 16.4% (10/61) had septal fibrosis (F3) or cirrhosis (F4) compared to 2.4% (1/41) among anti HCV positive/HCV RNA negative subjects (p=0.026). Of 18 HCV RNA positive subjects autopsied <15 years after HCV exposure none had F3 or F4. Among subjects autopsied >25 years after exposure 35% (6/17) had F3-F4. CONCLUSIONS Among IDUs chronically infected by HCV, 1/3 developed septal fibrosis or cirrhosis 25 years or more after exposure.
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Abstract
BACKGROUND AND STUDY AIM Valid tissue sampling of colorectal adenomas is crucial for their management in terms of treatment and follow-up. The aim of this study was to assess the validity of a cold biopsy sample as representative for the whole polypectomy specimen, with regard to histopathological features. PATIENTS AND METHODS As part of the Norwegian Colorectal Cancer Prevention trial, 442 participants (60% men) who fulfilled the criterion of colonoscopic recovery of adenoma that had been biopsied at flexible sigmoidoscopy, had their adenomas subsequently removed by polypectomy (snare resection) at colonoscopy. Logistic regression analysis was used to determine which variables contributed to the histopathological discrepancy between cold biopsy and polypectomy specimens. RESULTS Among the 532 colorectal adenomas biopsied at flexible sigmoidoscopy and removed by colonoscopy, the assessment of intraepithelial neoplasia (dysplasia) status was changed in 51 adenomas (10%), and 38 (7%) of them had been underestimated at biopsy compared with polypectomy. Likewise, the assessment of villousness was changed in 45 adenomas (9%), being upgraded in 26 (6%) at polypectomy compared with biopsy. In a multivariate model, the diameter of neoplasia at polypectomy was positively associated with increased risk of the underestimation of intraepithelial neoplasia and/or villousness influencing a diagnosis of advanced colorectal neoplasia, when cold biopsy and polypectomy specimens were compared ( Ptrend=0.01). Among 56 cases of advanced neoplasia, 35 (63%) showed only low-grade intraepithelial neoplasia on biopsy. CONCLUSIONS Biopsy-based diagnosis underestimated histopathological diagnosis in about 10% of colorectal adenomas detected by flexible sigmoidoscopy screening, but advanced neoplasia was underestimated in more than 60%. Efforts must be made to obtain polypectomy specimens to secure precise diagnosis.
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Lifestyle-related risk factors and chemoprevention for colorectal neoplasia: experience from the large-scale NORCCAP screening trial. Eur J Cancer Prev 2005; 14:373-9. [PMID: 16030428 DOI: 10.1097/00008469-200508000-00010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The objective of this study was to evaluate the potential beneficial effects of non-steroidal anti-inflammatory drugs (NSAIDs) and/or acetylsalicylic acid (ASA) and hormone replacement therapy (HRT) on colorectal neoplasia, and to compare their effects with those of lifestyle-related risk factors in 12 960 individuals who underwent flexible sigmoidoscopy screening examination. The association between these factors and colonic neoplasia was assessed by logistic regression analysis. NSAIDs and/or ASA intake were associated with decreased risk of distal low grade adenoma (DLGA) (adjusted odds ratio (OR) 0.80, P trend=0.02) in men. The duration of HRT was inversely related to the risk of DLGA (OR 0.89, P trend=0.08). Current smoking increased the risk of DLGA and distal advanced neoplasia (DAN) in both men (OR 2.50, P<0.01) and women (OR 2.30, P<0.01). There was a significant positive trend for increasing risk of DLGA (OR 1.16, P<0.01) and DAN (OR 1.20, P=0.02) with increasing use of alcohol among men, but not among women. Prescription of NSAIDs and/or ASA for chronic conditions may not be expected to have a substantial preventive effect on colorectal neoplasia in comparison with the adverse effect of smoking and alcohol. This may be explained by an increased risk of colorectal neoplasia for patients with conditions for which NSAIDs or ASA are being prescribed.
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Inter-endoscopist variation in polyp and neoplasia pick-up rates in flexible sigmoidoscopy screening for colorectal cancer. Scand J Gastroenterol 2003; 38:1268-74. [PMID: 14750648 DOI: 10.1080/00365520310006513] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND The Norwegian Colorectal Cancer Prevention study is an ongoing flexible sigmoidoscopy (FS) screening trial for colorectal cancer. Twenty-one thousand average-risk individuals, aged 50-64 years, living in two separate areas in Norway were randomly drawn from the Population Registry and invited to once-only screening flexible sigmoidoscopy. Examinations were performed over 3 years, at 2 centres, by 8 different endoscopists, using the same type of equipment. The aim of the present study was to investigate possible differences between endoscopists in detecting individuals with polyps, adenomas and advanced lesions (adenomas with severe dysplasia and/or villous components and/or size larger than 9 mm and carcinoma) in flexible sigmoidoscopy screening. METHODS The present trial comprises data from 8822 individuals, aged 55-64 years, who have undergone a flexible sigmoidoscopy. In the study period, all lesions detected by the different endoscopists were registered. Tissue samples were taken from all lesions detected. RESULTS Detection rates varied significantly between endoscopists, ranging from 36.4% to 65.5% for individuals with any polyp, from 12.7% to 21.2% for any adenoma and from 2.9% to 5.0% for advanced lesions. In a multiple logistic regression model, the performing endoscopist was a strong independent predictor for detection of individuals with polyps (P < 0.001 ), adenomas (P < 0.001) and advanced lesions (P = 0.01). CONCLUSION Detection rates for colorectal lesions vary significantly between endoscopists in colorectal cancer screening. Establishing systems for monitoring performance in screening programmes is important. Supervised training and re-certification for endoscopists with poor performance should be considered.
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The Norwegian Colorectal Cancer Prevention (NORCCAP) screening study: baseline findings and implementations for clinical work-up in age groups 50-64 years. Scand J Gastroenterol 2003; 38:635-42. [PMID: 12825872 DOI: 10.1080/00365520310003002] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Randomized controlled trials of sufficient power testing the long-term effect of screening for colorectal neoplasia only exist for faecal occult blood testing (FOBT). There is indirect evidence that flexible sigmoidoscopy (FS) may have a greater yield. The aim of this study was to determine the diagnostic yield of screening with FS or a combination of FS and FOBT in an average-risk population in an urban and combined urban and rural population in Norway. METHODS 20,780 men and women (1:1), aged 50-64 years, were invited for once-only screening (FS only or a combination of FS and FOBT (1:1)) by randomization from the population registry. A positive FS was defined as a finding of any neoplasia or any polyp > or = 10 mm. A positive FS or FOBT qualified for colonoscopy. RESULTS Overall attendance was 65%. Forty-one (0.3%) cases of CRC were detected. Any adenoma was found in 2208 (17%) participants and 545 (4.2%) had high-risk adenomas. There was no difference in diagnostic yield between the FS and the FS and FOBT group regarding CRC or high-risk adenoma. Work-up load comprised 2821 colonoscopies in 2524 (20%) screenees and 10% of screenees were recommended later colonoscopy surveillance. There were no severe complications at FS, but six perforations after therapeutic colonoscopy (1:336). CONCLUSIONS The present study bodes well for future management of a national screening programme, provided that follow-up results reflect adequate proof of a net benefit. It is highly questionable whether the addition of once-only FOBT to FS will contribute to this effect.
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Grading of distal colorectal adenomas as predictors for proximal colonic neoplasia and choice of endoscope in population screening: experience from the Norwegian Colorectal Cancer Prevention study (NORCCAP). Gut 2003; 52:398-403. [PMID: 12584223 PMCID: PMC1773542 DOI: 10.1136/gut.52.3.398] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND AND AIMS The purpose of this study was to evaluate the utility of easily measured clinical variables at flexible sigmoidoscopy (FS) screening that might predict a proximal advanced neoplasm (PAN). METHODS We studied 1833 subjects with biopsy verified adenomas at FS who subsequently underwent full colonoscopy. RESULTS A total of 387 (21%) subjects had proximal colonic neoplasms (PCN) and 85 (5%) had PAN. In univariate comparison, the risk of PAN increased more than threefold in the presence of a distal adenoma measuring either > or =10 mm in diameter or containing villous components. Multiplicity of distal adenomas, severe dysplasia, or age > or =60 years increased the risk of PAN more than twofold. In the multivariate model, the presence of a distal adenoma > or =10 mm, villousness, and multiplicity maintained their significance as predictive variables for increased risk of proximal neoplasms, whereas sex and severe dysplasia lost their significance. By recommending colonoscopy only to individuals with multiple (>1) adenomas or any high risk adenoma at FS, we would have reduced the number of colonoscopies by 1209 (66%) but would have missed 32 (38%) participants with PAN and 217 (56%) with PCN. By using a 60 cm endoscope instead of an ordinary colonoscope at FS, nine (2%) participants with advanced neoplasms, including three patients with cancer, would have been missed. CONCLUSION The present study supports the concept of defining "any adenoma" as a positive FS, qualifying for colonoscopy. We recommend the use of an ordinary colonoscope instead of a 60 cm sigmoidoscope for FS screening examinations.
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Age-dependent susceptibility to azoxymethane-induced and spontaneous tumorigenesis in the Min/+ mouse. Anticancer Res 2003; 23:259-65. [PMID: 12680222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
We examined the age-dependent susceptibility to azoxymethane (AOM)-induced and spontaneous tumorigenesis in the Min/+ mouse, a murine FAP model. The colon carcinogen AOM was given to pups (weeks 1 and 2) and young adults (weeks 4 and 5). In the colon, AOM exposure of pups and young adults caused a 17-fold and 10-fold increase (p < 0.001) in the number of dysplastic aberrant crypt foci (ACF) compared with vehicle-treated controls, respectively; the pups were 1.7 times mores susceptible than young adults (p = 0.002). AOM-specific dysplastic ACF grew significantly faster (p < 0.001) in pups than in young adults. In the small intestine of AOM-exposed pups, the number of adenomas was increased 1.5-fold compared with controls (p < 0.001), while a similar exposure of young adults did not affect the tumorigenesis. Dysplastic ACF in the colon were morphologically equivalent with nascent adenomas in the small intestine. When comparing the size distributions of AOM-specific and spontaneous lesions the majority of the spontaneous lesions was apparently initiated before week 2. In conclusion, pups were more susceptible than young adults to AOM-induced and spontaneous tumorigenesis, and neonatal exposure was not as critical for AOM-induced tumorigenesis in the colon as in the small intestine.
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Design, organization and management of a controlled population screening study for detection of colorectal neoplasia: attendance rates in the NORCCAP study (Norwegian Colorectal Cancer Prevention). Scand J Gastroenterol 2002; 37:568-73. [PMID: 12059059 DOI: 10.1080/00365520252903125] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND In the past three decades, the incidence of colorectal cancer (CRC) in Norway has doubled, surpassing all other Nordic countries for both men and women to become the most frequently diagnosed cancer. A small-scale, randomized study on flexible sigmoidoscopy (FS) screening in Telemark, Norway, has shown a reduction in accumulated CRC incidence after 13 years. The aim of our study was to evaluate the effect on CRC mortality and morbidity by screen detection of CRC and removal of precursor lesions (polypectomy), and to test out the management and organization mimicking a countrywide screening service. A total of 13,823 men and women (1:1), age 55-64 years, were drawn randomly from the population registries in Oslo (urban) and the county of Telemark (mixed urban and rural) and invited to have a screening examination. The rest of the relevant age cohorts constituted the control groups. In the screening group, 535 individuals were excluded according to exclusion criteria, rendering 13,288 individuals eligible for screening examination. METHODS A once only screening model was used. In the screening group, individuals were randomized to have a once only FS or a combination of FS and faecal occult blood test (FOBT). RESULTS The overall attendance rate was 8,849 out of 13,288 (67%); 73% in Telemark and 60% in Oslo. Attendance for FS only was 68% and 65% for combined FS&FOBT. CONCLUSIONS The present FSIFS&FOBT screening study obtained a high acceptance rate for both screening modalities. The attendance rate was stable throughout the trial, suggesting an acceptable model for management of future countrywide screening.
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Prognostic significance of the circumferential resection margin following total mesorectal excision for rectal cancer. Br J Surg 2002; 89:327-34. [PMID: 11872058 DOI: 10.1046/j.0007-1323.2001.02024.x] [Citation(s) in RCA: 509] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Knowledge of prognostic factors following resection of rectal cancer may be used in the selection of patients for adjuvant therapy. This study examined the prognostic impact of the circumferential resection margin on local recurrence, distant metastasis and survival rates. METHODS A national population-based rectal cancer registry included all 3319 new patients from November 1993 to August 1997. Some 686 patients underwent total mesorectal excision with a known circumferential margin. This shortest radial resection margin was measured in fixed specimens. None of the patients had adjuvant radiotherapy. RESULTS Following potentially curative resection and after a median follow-up of 29 (range 14--60) months, the overall local recurrence rate was 7 per cent (46 of 686 patients): 22 per cent among patients with a positive resection margin and 5 per cent in those with a negative margin (margin greater than 1 mm). Forty per cent of patients with a positive margin developed distant metastasis, compared with 12 per cent of those with a negative margin. With decreasing circumferential margin there was an exponential increase in the rates of local recurrence, metastasis and death. CONCLUSION The circumferential margin has a significant and major prognostic impact on the rates of local recurrence, distant metastasis and survival. Information on circumferential margin is important in the selection of patients for postoperative adjuvant therapy.
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Effect of vaccination with mutant KRAS peptides on rat colon carcinogenesis induced by azoxymethane. Anticancer Res 2002; 22:171-5. [PMID: 12017282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Rat colon carcinogenesis induced by 2 x 15 mg/kg body weight of azoxymethane (AOM) is a standard model, widely used to evaluate the role of nutritional components and chemopreventive agents at various stages of tumorigenesis. In this model, KRAS mutations have been frequently observed in aberrant crypt foci (ACF), putative preneoplastic lesions, as well as in tumours. Therefore we used this model and vaccinated F344 rats with a mixture of synthetic mutant KRAS peptides (MT KRAS) corresponding to frequent KRAS exon 1 mutations before AOM treatment in order to study the role of KRAS mutations in the development of ACF and subsequently tumours. The controls were sham-vaccinated with KRAS exon 1 wild-type KRAS peptides (WT KRAS). MT KRAS vaccination suppressed the number of ACF by 42% at week 13 (p=0.001). The subpopulation of ACF suppressed by MT KRAS vaccination had higher focal crypt multiplicity than the control ACF population (p=0.001). At week 26, vaccination reduced the KRAS mutation frequency in ACF from 50% in the MT KRAS group to 13% in the WT KRAS (p=0.038). However, at this phase of carcinogenesis, vaccination did not have significant effects on the ACF number and focal crypt multiplicity. Surprisingly, the KRAS mutation frequency was only 5% in the colonic tumours of the controls (1 out of 20 tumours). Although there were no tumours with KRAS mutations in the MT KRAS group, the possible effect of vaccination could not be evaluated. These data indicate that KRAS mutations play a minor role in colonic tumorigenesis and that ACF with KRAS mutations could hardly be the precursors of the AOM-induced tumours in rats. Hence, the cancer protective potential of a KRAS vaccine in the early phase of AOM-induced colon carcinogenesis in the rat appeared minuscule. Additional studies in a model with a high outcome of KRAS mutations in colonic tumours are needed to evaluate the effects of a KRAS vaccine at later stages of tumorigenesis.
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[Genetic analysis in familial adenomatous polyposis]. TIDSSKRIFT FOR DEN NORSKE LEGEFORENING 2001; 121:64-8. [PMID: 12013617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023] Open
Abstract
BACKGROUND Familial adenomatous polyposis (FAP) is an autosomal dominantly inherited disorder caused by germline mutations in the APC gene. FAP is characterised by a variable, but normally large number of colorectal adenomas and variations in extracolonic manifestations. These variations are associated with specific mutations of the APC gene. MATERIAL AND METHODS Representatives from 70 Norwegian families are under molecular investigation. Analyses have so far been concentrated on the part of the APC gene associated with classic FAP. RESULTS Germline mutations causing FAP have been identified in 36 of the 70 families examined. All mutations identified are confined to the first half of the gene and correlate to classic FAP. INTERPRETATION Because of the mutation heterogeneity in FAP, the size of the APC gene and variations in phenotype, it is a laborious task to identify the causative mutations. Better approaches to the analysis of the whole APC have now been established and will result in a higher degree of mutation detection independent of phenotype. Family history and phenotype-genotype correlations are still important guidelines for efficient molecular genetic analysis of the APC gene. Genetic surveillance, personal and socio-economic benefits from presymptomatic and predictive testing of members of FAP families are discussed.
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DNA adduct levels and intestinal lesions in congenic rapid and slow acetylator syrian hamsters admi food mutagens 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) or 2-amino-3-methylimidazo[4,5-f]quinoline (IQ). PHARMACOLOGY & TOXICOLOGY 2000; 86:257-63. [PMID: 10895988 DOI: 10.1111/j.0901-9928.2000.860603.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Epidemiological studies indicate that rapid acetylators with a high intake of well-done red meat have an increased risk of colorectal cancer. Arylamine N-acetyltransferase enzymes (E.C. 2.3.1.5) activate carcinogenic heterocyclic amines found in the crust of fried meat via O-acetylation of their N-hydroxylamines to reactive intermediates that bind covalently to DNA and produce mutations. Syrian hamsters as well as humans express two N-acetyltransferase isozymes (NAT1 and NAT2) which differ in substrate specificity and genetic control. Nucleic acid substitutions in the NAT2 gene segregate individuals into rapid, intermediate and slow acetylator phenotypes. In the present paper, we examined the role of the polymorphic NAT2 acetylator genotype in carcinogenesis induced by the food mutagens 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) or 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) by comparing Syrian hamster lines congenic at the NAT2 locus. No differences were found between rapid and slow acetylator congenic hamsters in levels of intestinal PhIP-DNA adducts. In contrast to previous studies in rats, no carcinogen-related induction of the preneoplastic lesions aberrant crypt foci or tumors was found in the intestines of rapid and slow acetylator congenic Syrian hamsters administered PhIP or IQ.
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Abstract
It is well established that use of alcohol increases the risk of fatal injuries. The presence of blood alcohol in autopsied deaths is regularly encountered in medico-legal practices. The aim of this study was to investigate the prevalence and concentration of alcohol in 1539 medico-legal autopsies in two counties in northern Norway in the period 1973-1992, and the reporting of acute alcohol influence among these deaths to the official cause-of-death statistics. Blood alcohol concentration (BAC) >/=0.5 per thousand (50 mg/100 ml) was found in 47.6% (n=456) of violent deaths tested, and in 93% (n=426) of these the BAC was >/=1.0 per thousand. In 17.4% (n=55) of tested natural deaths the BAC was >/=0.5 per thousand. Acute alcohol-influenced violent deaths were under-reported to the cause-of-death statistics. Deaths by motor vehicle traffic accidents did not differ from other violent deaths in this respect. The under-reporting among violent deaths was 41% in cases with BAC >/=0. 5 per thousand and 37% where the BAC was >/=1.0 per thousand during the whole period. It is concluded that post-mortem BAC >/=0.5 per thousand, should be regarded as a possible contributory cause in all violent deaths, and reported accordingly.
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Identification and quantification of aberrant crypt foci in the colon of Min mice--a murine model of familial adenomatous polyposis. Scand J Gastroenterol 2000; 35:534-9. [PMID: 10868458 DOI: 10.1080/003655200750023813] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Min mice are heterozygous for a nonsense mutation in the murine adenomatous polyposis coli (APC) gene and spontaneously develop multiple intestinal neoplasms similar to the familial adenomatous polyposis (FAP) syndrome in humans. Aberrant crypt foci (ACF) are assumed to be preneoplastic lesions in both murine and human colon carcinogenesis and have been observed in FAP patients. Light microscopic examination of the colonic mucosa of 42 Min mice did not show even a single 'classical' ACF on the basis of previously defined criteria, specifying that they are elevated above the surrounding mucosa. However, in Min mice we discovered aberrant crypt foci of a different type, which we denoted ACF(Min). In contrast to the classical type, ACF(Min) were not elevated above the surrounding mucosa, their detection was totally dependent on methylene blue staining and transillumination, and they could not be identified with scanning electron microscopy. Histopathologic examination of ACF(Min) showed dysplastic crypts, similar to those found in larger lesions--that is, microadenomas in the Min mouse. The number of ACF(Min) increased up to the age of 6 weeks and then seemed to remain at a constant level of approximately four per colon. In conclusion, by transillumination of whole-mount preparations stained with methylene blue, we have identified and quantified small microscopic lesions that may be precursors of colonic adenomas in Min mice.
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Pulmonary intravascular macrophages appear in rats after long-term administration of lipid emulsion and amino acid solution. An ultrastructural morphometric study. APMIS 1998; 106:687-92. [PMID: 9740506 DOI: 10.1111/j.1699-0463.1998.tb00212.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Intravascular macrophages have rarely been seen in normal lungs of humans and rats, but in rats endotoxaemia has induced their presence. To study whether substrates used for parenteral nutrition could have a similar stimulatory effect on mononuclear phagocytes, rats were given lipid emulsion (n=5), amino acid solution (n=5), or isotonic saline (n=5) through central venous catheters for 3 weeks. Structural changes in the lung microvessels were evaluated using electron microscopy. The areal fraction of pulmonary intravascular mononuclear phagocytes was 19.6% (SD=8.2) in rats given lipid emulsion (p<0.05) and 8.2% (SD=8.2) in rats given amino acid solution n.s. compared to 2.4% (SD= 4.0) in rats given saline. The increase in areal fraction was mainly due to an increase in cell numbers. In rats given lipid emulsion the intravascular phagocytes were only slightly larger than in rats given saline, but had the morphological features of mature macrophages. The study demonstrates that lipid emulsion recruits pulmonary intravascular macrophages in rats, indicating a stimulatory effect on the mononuclear phagocyte system. The effect was less pronounced with amino acid solution.
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Unexplained and explained natural deaths among persons above 1 year of age in a series of medico-legal autopsies. Forensic Sci Int 1998; 93:89-98. [PMID: 9717261 DOI: 10.1016/s0379-0738(98)00033-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The aim of this study was to describe unexplained and explained natural deaths among decreased above 1 year of age in a series of medico-legal autopsies collected over a 20-year period (1972-1992). Unexplained natural deaths can be defined as those deaths where no cause-of-death is revealed after post-mortem and without circumstances indicating violent death. The death was considered to be natural in 491 cases above 1 year of age among a total of 2004 medico-legal autopsies. In 428 of these cases an explanation as to the cause-of-death was reached. The three most frequently encountered causes-of-death were complications to coronary atherosclerosis (62.6%), diseases of the lung (12.4%) and diseases in the central nervous system (9.8%). Among 59 cases with unexplained natural death, 50 had various chronic diseases or fatty liver. In 43 of these cases the deceased had epilepsy or chronic alcoholism. In nine cases (1.8% of the natural deaths) no explanation to the cause-of-death could be given.
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Abstract
The aim of this paper is to describe the characteristics of medicolegal autopsies of violent deaths in northern Norway over a period of 20 years. On request by the police, 1446 violent deaths were examined--82.6% males and 17.4% females. The mean age was 40.2 years (range 0-98). The most frequent violent manners of death were suicides (24.9%), deaths caused by motor vehicle traffic accidents (18.6%), accidental poisoning (11.5%) and boating incidents (8.4%). Homicides and involuntary manslaughter came to 4.4% and 1.7%, respectively, whereas in 11.4% of cases the manner of death was unknown. The five most frequent causes of death were blunt injury (31.4%), drowning (17.4%), suffocation (11.8%), firearm (11.3%) and poisoning (10.5%). In 3.5% of the cases the cause of death was unknown. The spectrum of the manner of death and the cause of death in a subarctic population is discussed with reference to legislation, practise of request and information given by the police.
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2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine increases the numbers of tumors, cystic crypts and aberrant crypt foci in multiple intestinal neoplasia mice. Carcinogenesis 1997; 18:1049-54. [PMID: 9163695 DOI: 10.1093/carcin/18.5.1049] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The multiple intestinal neoplasia (Min) mice have a mutation in the murine adenomatous polyposis coli (Apc) gene rendering them highly susceptible to spontaneous intestinal adenoma formation, similar to the familial adenomatous polyposis (FAP) syndrome in humans. We studied whether the most abundant mutagenic heterocyclic amine isolated from cooked food, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), could influence early intestinal neoplasia in C57BL/6J-Min/+ and C57BL/6J- +/+ (wild-type) mice of both sexes. PhIP was given in 4 weekly i.p. injections of 50 mg/kg. Ten weeks after the start of the experiment, PhIP had significantly increased the numbers of small tumors and cystic crypts in the proximal section of the small intestine in male Min/+ mice, and the numbers of aberrant crypt foci (ACF) in the large intestines of both males and females. The effects of PhIP were more pronounced in male than in female Min/+ mice. In +/+ mice, no tumors or cystic crypts in the small intestine, and no tumors and only a very few ACF in the large intestine, were induced by PhIP. These results show that a substance frequently present in the human diet is able to enhance the neoplastic process induced by a genetic lesion, which is also commonly found both in inherited and sporadic colon carcinomas in humans.
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Lipid entrapment and cellular changes in the rat myocard, lung and liver after long-term parenteral nutrition with lipid emulsion. A light microscopic and ultrastructural study. APMIS 1996; 104:515-22. [PMID: 8920804 DOI: 10.1111/j.1699-0463.1996.tb04906.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We have demonstrated organ damage after long-term administration of lipid-based parenteral nutrition, possibly initiated by intravascular pooling of lipid and phagocytes, in both rats and pigs. To evaluate whether accumulation of lipid could simply be caused by mechanical filtration, a comparative study of three separate capillary beds was performed. Rats were given lipid emulsion (n = 5) or isotonic saline (n = 4) through central venous catheters for 3 weeks. Using both light and electron microscopy, lipid accumulation and structural changes in the rat myocard were compared to those in the lung and liver. The study provides evidence that within myocardial capillaries both peripheral blood monocytes and endothelial cells performed phagocytosis of lipid droplets following administration of lipid emulsion, but no large-scale intravascular pooling of lipid resulted. Morphometry of the myocard detected no lipid increase in the myocytes from the rats given lipid emulsion compared with controls and in neither were there any stigmata of vasculitis or myocardial damage, in contrast to the lung and liver, where intravascular pooling of lipid and phagocytes was seen. This indicates that phagocytosis was an important mechanism involved in entrapment and elimination of lipid.
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Forensic pathology in northern Norway. Requested medico-legal autopsies in the counties of Finnmark and Troms 1973-1992. APMIS 1996; 104:465-74. [PMID: 8774677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The aim of this study was to analyse medico-legal autopsy rates among Norwegian citizens who died in the two northernmost counties of Norway during the 20-year period 1973-1992. Medico-legal autopsy rate was defined as the number of medico-legal autopsies divided by the total number of deaths. The rates were calculated according to year of death, manner of death, sex, age, police district and county. The material included 1539 medico-legal autopsies. In the total 20-year period 37.9% (n = 1113) of the violent deaths and 1.2% (n = 426) of the natural deaths were subjected to medico-legal autopsy. The annual rates increased gradually up to 1987. In the last 5-year period 51.7% of the violent deaths and 2.1% of the natural deaths were subjected to medico-legal autopsy. Among violent deaths in this period the medico-legal autopsy rates were: suicides 65.7%, motor vehicle traffic accidents 58.3%, falls 8.6%, and other violent deaths 77.1%. Females dying after a fall and due to natural causes were significantly less frequently than males subjected to medico-legal autopsy. These two categories of death also revealed a significant decrease in autopsy rate with increasing age (age group 0-29, 30-59 and > or = 60 years) in each 5-year period. In cases of violent death the medico-legal autopsy rate according to police district varied from 24.1% to 88.9% in the last 5-year period. In conclusion, medico-legal autopsy rates depended on manner of death, sex, age and police district, besides changes in legislation.
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Morphological modifications of apoptosis in HL-60 cells: effects of homocysteine and cytochalasins on apoptosis initiated by 3-deazaadenosine. Virchows Arch 1995; 426:257-66. [PMID: 7773505 DOI: 10.1007/bf00191363] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Using electron microscopy, confocal laser scanning microscopy and measurements of intact DNA we have studied the morphology and DNA degradation of human leukaemia HL-60 cells undergoing drug initiated apoptosis. Apoptosis was initiated by 100 microM 3-deazaadenosine (c3Ado), 25 microM c3Ado plus 1 mM homocysteine thiolactone (Hcy) and 100 microM c3Ado plus 5 micrograms/ml cytochalasin B (CB). Two different phenotypes of apoptotic cells (APC), blebbed and non-blebbed, were present in the cultures. Blebbed APC dominated in cultures exposed to c3Ado, whereas most APC in cultures treated with c3Ado plus Hcy and all the APC in cultures treated with c3Ado plus CB displayed a non-blebbed phenotype. A more pronounced reduction of the chromatin/cytoplasm ratio, lower volume fractions of uncondensed chromatin and higher volume fractions of highly condensed chromatin (micronuclei) were found in cultures exposed to c3Ado and c3Ado plus Hcy when compared with cultures exposed to c3Ado plus CB. A partial inhibition of c3Ado apoptosis by CB was confirmed by measurements of intact DNA. The inhibitory effect of CB was not reproducible by CE, indicating that CB exerts its effect by an actin independent mechanism. Both blebbed and non-blebbed APC displayed nuclear fragmentation, segregation of organelles and cytoplasmic vesiculation, suggesting that the differences between the phenotypes were restricted to the cytoplasmic membrane. We were not able to demonstrate the presence of F-actin by fluorescein isothiocyanate-phalloidin staining in blebbed APC nor in non-blebbed APC in cultures treated with c3Ado plus Hcy. Non-blebbed APC in cultures treated with c3Ado plus CB displayed foci of F-actin at the internal part of the cytoplasmic membrane. This suggests that F-actin is preserved by the mechanism by which CB inhibits blebbing, and may indicate that blebbing of the cytoplasmic membrane during apoptosis is associated with F-actin deficiency rather than a result of actin-myosin interactions.
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Cystic lymphangioma of the small bowel mesentery. THE EUROPEAN JOURNAL OF SURGERY = ACTA CHIRURGICA 1995; 161:203-205. [PMID: 7599300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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Abstract
Telepathology is moving from the experimental stage to become a regular feature of pathology practice. This has been made possible by technical advances in telecommunications and image processing. Since 1990 the University Hospital of Tromsø has provided local hospitals in northern Norway with a remote frozen section service and with access to video conferences for the review of microscopic findings and for the discussion of major diagnostic issues. Several other hospitals in Norway are now participating in this development and practical relations among pathology laboratories for the purpose of consultation and education will be the next step in the procedure. Similar developments in telepathology have taken place in other countries. Standardization of network and telepathology workstations will be needed before extensive international collaboration can be achieved. Progress in high quality video devices, high capacity telecommunication lines and improved image compression techniques will increase the usage of telepathology services and make them cost-effective. Thus, telepathology will contribute to the development of pathology services in the next century.
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[Cystic lymphangioma of the mesentery]. TIDSSKRIFT FOR DEN NORSKE LEGEFORENING 1994; 114:793-4. [PMID: 8009497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Cystic lymphangioma of the mesentery is a rare congenital lesion with a relatively low growth potential. It is typically found in young adults, and thereby excluded from other, more aggressive lymphatic malformations seen in newborns. Symptoms of onset may be dramatic and sudden, but are often preceded by an interval of diffuse abdominal discomfort, possibly associated with loss of weight and a palpable abdominal mass. The multicystic architecture of the lesion is clearly visible on an abdominal CAT-scan and indicates the diagnosis. Percutaneous drainage of the cysts has neither diagnostic nor therapeutic effects. Radical excision of the expansion may include resection of the related intestinal segment. Lymphangioma of the mesentery is not malignant. We suggest an ultrasound follow-up six months after the intervention to establish whether the surgery has been successful.
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Renal and hepatic toxicity after high-dose 7-hydroxymethotrexate in the rat. Cancer Chemother Pharmacol 1994; 34:119-24. [PMID: 8194163 DOI: 10.1007/bf00685928] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
To examine directly the hepatic and renal toxicity of 7-hydroxymethotrexate (7-OH-MTX) without interference of the parent compound methotrexate (MTX), we purified and gave 100 mg/kg 7-OH-MTX to rats, a dose resulting in serum levels of 7-OH-MTX comparable with those achieved in the clinic after the administration of high-dose MTX (HD-MTX). After only 5 h, the 7-OH-MTX-treated rats demonstrated 2.6-fold increases in serum creatinine values and 2-fold elevations in serum aspartate aminotransferase (ASAT) levels as compared with the controls. Morphologic evidence of toxicity, however, was apparent only in the kidneys. Intraluminal cellular debris containing membranous material and deteriorated organelles was seen, but no precipitate of the delivered drug. The peak serum concentration of 7-OH was up to 939 microM, and concentrations of 7-OH-MTX declined triphasically, showing a t1/2 alpha value of 2.45 min, a t1/2 beta value of 30.5 min, and a terminal half-life (t1/2 gamma) of 240 min. The total clearance value was 14.5 ml min-1 kg, and the postdistributional volume of distribution (V beta) was 5070 ml/kg. Our results may indicate a direct toxic effect of 7-OH-MTX on kidney and liver cells.
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Cell death initiated by 3-deazaadenosine in HL-60 cells is apoptosis and is partially inhibited by homocysteine. Biochem Pharmacol 1993; 46:1893-901. [PMID: 8267639 DOI: 10.1016/0006-2952(93)90629-b] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Cell death initiated by the adenosine analog 3-deazaadenosine (c3 Ado) was studied in human promyelocytic leukemia HL-60 cells. A rapid decrease in cell number was seen after 4-hr exposure to 50-100 microM c3 Ado. The dominating mode of cell death was apoptosis as demonstrated by condensation and fragmentation of the nucleus, formation of apoptotic bodies and endonucleolytic degradation of DNA. Four hour treatment with 100 microM c3 Ado resulted in a reduction of early S-phase cells, and appearance of cells with a lower DNA and protein content than that of the G1 population. Whereas 25 and 50 microM c3 Ado only initiated apoptosis in S-phase cells, 75 and 100 microM c3 Ado also initiated apoptosis in G1- and G2 + M-phase cells, suggesting different mechanisms for cell death at different concentrations. Apoptosis initiated by 100 microM c3 Ado was completely inhibited by 1 mM ZnCl2. Addition of homocysteine thiolactone (Hcy) partly inhibited cell death by c3 Ado. Light microscopic examination of cultures treated with 100 microM c3 Ado and 1 mM Hcy showed nuclear condensation and fragmentation consistent with the first stage in apoptosis, however, only a minor formation of apoptotic bodies took place in these cultures compared to that observed in cultures treated with 100 microM c3 Ado alone. The modifying action of Hcy on c3 Ado initiated apoptosis in HL-60 cells and this suggests that c3 Ado and 3-deazaadenosylhomocysteine (c3 AdoHcy) interact with different targets during initiation and progression of cell death in this cell line.
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Abstract
BACKGROUND The aim of this study was to combine an epidemiologic survey of colorectal cancer among Maori, Polynesian, and white inhabitants of New Zealand with a detailed analysis of tumor subsite and histopathology. METHODS Data were obtained from the New Zealand National Cancer Registry and included all registrants from 1970 to 1984. Sections of histologic specimens of colorectal cancer of Maori and non-Maori were retrieved from three Auckland hospitals. RESULTS The annual age-adjusted incidence rates of large intestinal cancer among male and female Maoris and male and female Polynesians were 40%, 40%, 39%, and 29%, respectively, of the total population incidence. Time-trend analysis showed the incidence of large intestinal cancer to be increasing among all racial groups. The relative proportion of rectal cancers was higher in male and female Maoris and female Polynesians than in the general population, whereas male Polynesians had a relatively high proportion of right colonic cancers. High-grade carcinoma and mucinous carcinoma occurred more frequently in young individuals regardless of race. Carcinomas were diagnosed at a more advanced stage in Maoris. CONCLUSION Given the similar environmental characteristics of the three racial groups, the findings indicate the presence of powerful protective factors in Maoris and Polynesians. These could be constitutional or mediated by unrecognized dietary constituents.
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Abstract
BACKGROUND The aim of this study was to combine an epidemiologic survey of colorectal cancer among Maori, Polynesian, and white inhabitants of New Zealand with a detailed analysis of tumor subsite and histopathology. METHODS Data were obtained from the New Zealand National Cancer Registry and included all registrants from 1970 to 1984. Sections of histologic specimens of colorectal cancer of Maori and non-Maori were retrieved from three Auckland hospitals. RESULTS The annual age-adjusted incidence rates of large intestinal cancer among male and female Maoris and male and female Polynesians were 40%, 40%, 39%, and 29%, respectively, of the total population incidence. Time-trend analysis showed the incidence of large intestinal cancer to be increasing among all racial groups. The relative proportion of rectal cancers was higher in male and female Maoris and female Polynesians than in the general population, whereas male Polynesians had a relatively high proportion of right colonic cancers. High-grade carcinoma and mucinous carcinoma occurred more frequently in young individuals regardless of race. Carcinomas were diagnosed at a more advanced stage in Maoris. CONCLUSION Given the similar environmental characteristics of the three racial groups, the findings indicate the presence of powerful protective factors in Maoris and Polynesians. These could be constitutional or mediated by unrecognized dietary constituents.
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Frozen section service via the telenetwork in northern Norway. ZENTRALBLATT FUR PATHOLOGIE 1992; 138:409-12. [PMID: 1297433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
We present preliminary results of remote frozen section service for two local hospitals in Northern Norway. The service is arranged by remote controlling microscopes with motorized X, Y and Z stage movements, magnification and illumination located at Kirkenes and Harstad Hospitals at a distance up to 400 km apart from the workstation at the University Hospital in Tromsø. The video-images of the frozen section are transmitted via a two-ways phone and video telenetwork with 2 Mbit/s capacity. The images are displayed on a monitor as both still and live images and diagnosed by pathologists in Tromsø. To data, 50 patients are examined by remote frozen section service. Correct benign versus malignant diagnoses are given in all cases compared with final diagnoses based on formalin fixed and paraffin embedded material except for two false negative malignant cases and two deferred diagnoses. The average time taken for examining each case of frozen section was 13 minutes. For hospitals with limited requirement of local pathology service and for hospitals with deficiency of specialists, remote frozen section service may be a worthwhile substitute.
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The validity of frozen section diagnosis based on video-microscopy. ZENTRALBLATT FUR PATHOLOGIE 1992; 138:405-7. [PMID: 1297432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
To investigate the accuracy of video-microscopy of frozen sections, two pathologists reexamined 80 cases of archival material, on which frozen sections had previously been performed. Diagnoses based on the two trials (Observer 1 and 2) and diagnoses obtained in the original frozen section situation were compared with the final diagnoses based on paraffin embedded material. Observer 1 had two false negative diagnoses, but no false positive, whereas Observer 2 had one false positive, but no false negative diagnosis when compared with the final diagnoses. No false positive or false negative diagnoses were made in the original frozen sections situation and the number of inconclusive diagnoses were 5, as compared with 6 and 8 in the two trials based on video-microscopy. More experience with video-microscopy will probably achieve a quality of frozen section diagnoses similar to that of direct light-microscopy.
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Immunolocalization of cystatin A in neoplastic, virus and inflammatory lesions of the uterine cervix. Acta Histochem 1992; 93:241-8. [PMID: 1326833 DOI: 10.1016/s0065-1281(11)80215-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Cystatin A was immunohistochemically demonstrated in the normal squamous epithelium of the uterine cervix, particularly in the parabasal and superficial cell layers whereas it was absent or scanty in the basal cells and in areas with parakeratosis. Cystatin A was also found in neoplastic lesions (dysplasia, carcinoma in situ and squamous cell carcinoma), but less abundant than in normal squamous epithelium. The immunoreaction in intraepithelial neoplasia was closely related to the degree of morphological maturation of the squamous cells with more abundant cystatin A in low grade dysplasia and less in high grade dysplasia and carcinoma in situ. In squamous cell carcinoma, cystatin A was often abundant in highly differentiated areas and almost absent in poorly differentiated ones. Cystatin A was found in the squamous epithelium in herpes and in condylomatous lesions. It was also found in the cytoplasm of neutrophils, but not in lymphocytes and plasma cells. In unspecific cervicitis, cystatin A was found extracytoplasmatically as small vesicles in the epithelial-stromal junction. The implications of cystatin A in neoplastic, virus, and inflammatory processes are discussed.
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Abstract
Acute hepatotoxicity after administration of 10-1000 mg/kg methotrexate (MTX) to rats was studied by monitoring serum transaminases, liver morphology, and disposition kinetics of MTX and 7-hydroxy-methotrexate (7-OH-MTX). Half the control rats and rats administered 1000 mg/kg MTX, had their bile duct cannulated. One to 2 hr after administration of 1000 mg/kg MTX, 50% of MTX treated bile-drained rats (Ebc) developed cholestasis despite similar or larger initial bile flow rates than those which did not develop cholestasis (Ebn, controls). In Ebc animals, peak serum ASAT and ALAT levels were 6- and 4-fold higher than that of the control rats, and morphologically, prominent hepatocytic changes and grossly dilated bile canaliculi were found. Immediately prior to cholestasis, the Ebc animals reached biliary 7-OH-MTX levels (8.3 +/- 1.3 mM, mean +/- S.E.M.) which were equivalent to the threshold level for precipitation of 7-OH-MTX in rat bile in vitro, and 3-fold higher than the corresponding levels of 7-OH-MTX in the bile of Ebn rats. Ninety-five % of the drug in the precipitated material was 7-OH-MTX. Hence, 7-OH-MTX may play a role in acute MTX hepatotoxicity, a dose-limiting toxicity that may not be counteracted by leukovorin rescue.
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Abstract
We discuss the organization of a remote frozen section service in northern Norway. The service is operated by remote control of a motorized video-microscope located at Kirkenes Hospital, at a distance of more than 400 km from the workstation at the University Hospital in Tromsø. The video images of the frozen section are transmitted via a two-way telephone and video telenetwork with a 2 Mbit/s capacity. The images are displayed on monitors and diagnosed by pathologists in Tromsø. To date, 17 patients have been examined by remote frozen section. Correct benign versus malignant diagnoses have been given in all 17 cases compared with final diagnoses based on formalin-fixed and paraffin-embedded material. The average time taken for examining each frozen section was 15 minutes (range, 5 to 30 minutes). In none of the cases was the interpretation of the slides difficult due to deficient quality of the video images. For small hospitals with limited availability of local pathology services and for hospitals with a deficiency of specialists, telepathology may be a worthwhile substitute.
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The risk of cancer at all sites following gastric operation for benign disease. A cohort study of 4,224 patients. Int J Cancer 1991; 48:333-9. [PMID: 2040526 DOI: 10.1002/ijc.2910480304] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
This report represents the results of a historical cohort analysis of 3,360 males and 864 females who had a gastric resection or gastroenterostomy for benign disease between 1990 and 1969. Within the period 1970 to 1988 the cohort was cross-checked with the data files at the Cancer Registry of Norway to identify the patients in whom cancer had been diagnosed. When analyzed according to cancer sites, increased risk was recorded for the oropharynx, stomach, colon, pancreas, liver, biliary tract, larynx, lungs, urinary bladder and non--melanomatous cancers of the skin in males. In females, increased risk was only observed for the oropharynx, but was close to a statistically significant level also for cancer of the stomach. A lower number of tumors of the central nervous system than expected was observed in both males and females. The increased risk of cancer of the lungs, larynx and urinary bladder in males can be regarded as evidence of the high prevalence of smokers in the cohort. We suggest that the increased risk of cancer of digestive organs is mainly related to life-style factors, particularly tobacco-specific nitrosamines whose effect is enhanced by surgical sequelae.
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[Occurrence of recurrence after regression of low-grade dysplasia in vaginal cytological smears]. TIDSSKRIFT FOR DEN NORSKE LEGEFORENING 1991; 111:328-9. [PMID: 2000616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
329 females with regress of low-grade dysplasia were followed up by annual vaginal smears for a maximum of 14 years. 53 developed recurrence of dysplasia. The average annual risk of recurrence was greatest 2-4 years after regress, being 4.3%. The average annual risk of recurrence for those followed up for more than ten years was 0.5%. None of the females developed cervical cancer. It is concluded that annual controls may prevent females with regress of previous low-grade dysplasia from developing cancer. After ten years with no further dysplasia, the females are recommended to follow the general practice for persons without previous dysplasia or cancer.
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[Use of telecommunications in pathology and anatomy services]. TIDSSKRIFT FOR DEN NORSKE LEGEFORENING 1991; 111:17-9. [PMID: 2000579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Telepathology comprises the transmission of microscopic images via the telecommunications network. This paper describes the first experiences from this new technology in Norway. These include teleconferences based on showing histologic slides from the Department of Pathology at the University Hospital in Tromsø to clinicians at local hospitals. A frozen section service to Kirkenes Hospital, based on remote control of a robotic microscope and transmission of high quality video images of the slide, has also been successfully established.
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[Breast tumor--a diagnostic challenge]. TIDSSKRIFT FOR DEN NORSKE LEGEFORENING 1990; 110:819-22. [PMID: 2321204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The study includes all patients referred for surgical examination with suspected breast cancer (n = 439) during a single year. All women were examined clinically. Mammography was performed in 372 cases (88%), and 195 (46%) women underwent biopsy. 37 (8.7%) of the admitted women had breast cancer, which was verified by histological examination. This corresponds to an incidence rate of 0.8 per 1,000 women, and an incidence rate of 2.0 per 1,000 in women above 40 years. In four patients who were not suspected as having breast cancer after clinical examination, breast cancer was revealed by mammography. However, mammography alone is insufficient, since three mammograms were false negative, in cases where cancers were diagnosed clinically. Therefore, both mammography and clinical investigation are necessary in the examination of women with breast tumors. When breast cancer cannot be ruled out by physical and mammographic examination, a representative specimen of the tumor should be removed for histological or cytological examination.
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41
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[Aspiration cytology of the breast]. TIDSSKRIFT FOR DEN NORSKE LEGEFORENING 1989; 109:2282, 2308. [PMID: 2772892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
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42
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Organ changes in pigs after longterm parenteral nutrition. Clin Nutr 1989; 8:29-33. [PMID: 16837263 DOI: 10.1016/0261-5614(89)90022-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/1987] [Accepted: 05/20/1988] [Indexed: 11/29/2022]
Abstract
When nutritional substrates used in clinical parenteral nutrition are given to rats a number of organ changes have been reported. These could be a species-related effect without significance outside the experimental laboratory. The reproduction of such organ changes in a large unrelated species would increase their importance. Longterm complete parenteral nutrition (CPN) was given to piglets. Nutritional substrates accepted in human parenteral nutrition were used, and the animals were parenterally fed for 6 and 12 weeks. Autopsy demonstrated an increased splenic weight. Epithelioid cell infiltration was found in the liver, spleen and lung. Osmiophilic fat droplets and vascular inflammation were seen in the pulmonary arteries. No signs of infections were found.
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43
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[Aspiration cytology of the breast. Evaluation of 15-years case material]. TIDSSKRIFT FOR DEN NORSKE LEGEFORENING 1988; 108:1765-7. [PMID: 3420580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
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44
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Late occlusion of expanded Teflon femoropopliteal graft due to calcification and fracture of implant. Case report. ACTA CHIRURGICA SCANDINAVICA 1988; 154:473-4. [PMID: 3188796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A case of occlusion and thrombosis in a femoropopliteal Teflon implant is presented. The mechanism was fracture of the calcified capsule around the graft, intermittent stenosis at the fracture site and gradual thrombus formation.
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45
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[Meckel's diverticulum]. TIDSSKRIFT FOR DEN NORSKE LEGEFORENING 1987; 107:2853-4. [PMID: 3501176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
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46
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[The diagnostic basis for cancer registration in Norway]. TIDSSKRIFT FOR DEN NORSKE LEGEFORENING 1987; 107:2865-8. [PMID: 3424326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
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47
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Dysplasia in colorectal adenomas related to the presence of O-acylated sialic mucin and to morphometric measurements. ACTA PATHOLOGICA, MICROBIOLOGICA, ET IMMUNOLOGICA SCANDINAVICA. SECTION A, PATHOLOGY 1987; 95:365-9. [PMID: 3687439 DOI: 10.1111/j.1699-0463.1987.tb00053_95a.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
In a study of 41 surgically removed colorectal adenomas of unselected size, the dysplasia was graded as mild in 9, as moderate in 22, and severe in 10 cases. Twenty-four of the lesions were classified as tubular adenomas and 17 as tubulo-villous. The presence of O-acylated sialic mucin was for each of the adenomas assessed as normal (19 cases), intermediate (13 cases) or absent (9 cases). The absence of O-acylated mucin was in the present study found to be highly predictive for severe dysplasia (89%). The morphometric measurements of epithelial structures showed that nuclear shape factor and nuclear stratification index were most significantly related to the grades of dysplasia. In a multivariate analysis, the grading of O-cylated sialic mucin most significantly contributed to the grade of dysplasia, and to a lesser degree, nuclear shape factor and nuclear stratification index. The presence of villous elements and the size of the adenomas had no independent influence on the grade of dysplasia in this statistical analysis.
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48
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Cancer of the uterine cervix in Norway by histologic type, 1970-84. J Natl Cancer Inst 1987; 79:199-205. [PMID: 3474452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
A total of 6,202 patients with cancer of the uterine cervix was reported to the Cancer Registry in Norway from 1970 to 1984. Squamous cell carcinoma was reported in 86.1% of all cases, adenocarcinoma in 9.5%, and undifferentiated cancer in 3.6%; the heterogeneous group of "other malignant neoplasms" was 0.8% of all cases, most of which were sarcomas. During the 15-year period the average annual age-adjusted incidence rates for both squamous cell carcinoma and undifferentiated cancer decreased by 30 and 79%, respectively, whereas adenocarcinoma increased by 38%. The increase of adenocarcinoma was mostly confined to females 20-34 years of age. The decrease in incidence rates of undifferentiated cancer was observed in all age groups, whereas the fall in incidence rates for squamous cell carcinoma was demonstrated in females above 35 years of age only. Of all patients with squamous cell carcinoma, 55% were diagnosed in clinical stage I. Females with adenocarcinoma and undifferentiated cancer were diagnosed in stage I in 60 and 38% of the cases, respectively. The 5- and 10-year relative survival rates were highest for patients with squamous cell carcinoma at all stages, whereas a significantly less favorable prognosis was found for females with adenocarcinoma and undifferentiated cancer of the uterine cervix.
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49
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[Cervical neoplasms. A study of conditions influencing the occurrence of false negative tests]. TIDSSKRIFT FOR DEN NORSKE LEGEFORENING 1987; 107:1204-6, 1211. [PMID: 3603478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
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50
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[Cervical cancer. Reduced occurrence and mortality in Tromsö and Finnmark 1973-1984]. TIDSSKRIFT FOR DEN NORSKE LEGEFORENING 1987; 107:1199-203. [PMID: 3603477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
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