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1.
Cell Mol Life Sci ; 71(19): 3811-28, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24522256

ABSTRACT

Cell-matrix interactions control outgrowth of mammary epithelium during puberty and pregnancy. We demonstrate here that the glycoprotein fibulin-2 (FBLN2) is strongly associated with pubertal and early pregnant mouse mammary epithelial outgrowth. FBLN2 was specifically localized to the cap cells of the terminal end buds during puberty and to myoepithelial cells during very early pregnancy (days 2-3) even before morphological changes to the epithelium become microscopically visible, but was down-regulated thereafter. Exposure to exogenous oestrogen (E2) or E2 plus progesterone (P) increased Fbln2 mRNA expression in the pubertal gland, indicating hormonal control. FBLN2 was co-expressed and co-localised with the proteoglycan versican (VCAN) and co-localised with laminin (LN), while over-expression of FBLN2 in HC-11 cells increased cell adhesion to several extracellular matrix proteins including LN and fibronectin, but not collagens. Mammary glands from Fbln2 knockout mice showed no obvious phenotype but increased fibulin-1 (FBLN1) staining was detected, suggesting a compensatory mechanism by other fibulin family members. We hypothesise that similar to embryonic aortic smooth muscle development, FBLN2 and VCAN expression alters the cell-matrix interaction to allow mammary ductal outgrowth and development during puberty and to enable epithelial budding during pregnancy.


Subject(s)
Calcium-Binding Proteins/metabolism , Extracellular Matrix Proteins/metabolism , Extracellular Matrix/metabolism , Mammary Glands, Animal/metabolism , Animals , Calcium-Binding Proteins/deficiency , Calcium-Binding Proteins/genetics , Cell Movement/drug effects , Cells, Cultured , Estrogens/pharmacology , Extracellular Matrix Proteins/deficiency , Extracellular Matrix Proteins/genetics , Female , Fibronectins/metabolism , Laminin/analysis , Laminin/metabolism , Male , Mammary Glands, Animal/cytology , Mammary Glands, Animal/drug effects , Mice , Mice, Inbred C57BL , Mice, Knockout , Pregnancy , Progesterone/pharmacology , RNA, Messenger/metabolism , Versicans/analysis , Versicans/metabolism
3.
J Sports Med Phys Fitness ; 43(3): 285-90, 2003 Sep.
Article in English | MEDLINE | ID: mdl-14625508

ABSTRACT

AIM: The purpose of this study was to measure the effects of drafting on energy expenditure in in-line skating, and to investigate whether the "benefit of drafting", i.e. the decrease in energy expenditure, was different between two velocities and two distances separating the two skaters. METHODS: Eight recreational in-line skaters performed six exercises of 6 min, at 2 velocities (V(1) = 5.51+/-0.45 m x sec(-1); V(2) = 7.01+/-0.67 m x sec(-1)) in 3 conditions (ND = without drafting; D(1)=0.74-0.87 m "close"; D(2) = 1.19-1.36 m "far"). Collection of expired gas was carried out using a breath-by-breath portable gas analyser K4(b2) and the distance between the skaters was measured by video analysis. RESULTS: The skaters' energy expenditure was reduced in all drafting conditions; between D(1) and ND by 9.6+/-4.4% at V(1) and by 2.7+/-3.3% at V(2); between D(2) and ND by 8.8+/-6.0% at V(1) and by 4.2+/-4.8% at V(2). This reduction was significantly (p<0.05) more important at V(1) than V(2) and no differences were observed between D(1) and D(2). CONCLUSION: In in-line skating, the technical difficulties for drafting efficiently, especially while cornering, resulted in a reduced "benefit of drafting" at high velocity than in other sports. Moreover, the need for the subject to adjust their own cycle frequency to that of the lead skater while drafting "close" would explain partly that there were no significant differences between drafting at D(1) and D(2). These results suggest that the drafting technique should be emphasized in training, especially in non-skilled skaters at high velocities and when cornering.


Subject(s)
Air Movements , Biomechanical Phenomena , Energy Metabolism/physiology , Skating/physiology , Adult , Exercise/physiology , Humans , Lactic Acid/blood , Male , Oxygen Consumption/physiology , Reference Values
4.
J Pathol ; 195(4): 422-8, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11745673

ABSTRACT

The development of Herceptin (Trazumatab) makes testing for HER2 status important for choosing optimal therapy in breast cancer. This study addresses the precision, accuracy, and reproducibility of HER2 assays. HER2 was assessed retrospectively by immunohistochemistry (IHC) with Dako 'Herceptest', by IHC with the monoclonal antibody CB11, and by fluorescence in situ hybridization (FISH, PathVysion), in a series of 216 formalin-fixed breast carcinomas including 191 for which quantitative HER2 data from radioimmunohistochemistry (Q-IHC) were available. All tests were scored independently by two observers. Positivity rates varied between Herceptest (12.6%), FISH (19.4%), and CB11 IHC (28.5%). Kappa values showed that IHC-based tests were more susceptible to inter-observer variation (kappa=0.67 and 0.74 for Herceptest and CB11, respectively) than FISH (kappa=0.973). Overall test accuracy (see the Materials and methods section) for CB11 IHC (83.8%) was lower than Herceptest (87.4%) or FISH (93.2%). FISH predicted p185 HER2 overexpression (determined by Q-IHC) better (concordance index C.Ind. 0.90) than CB11 IHC (C.Ind.=0.85) or Herceptest (C.Ind.=0.81). Of 42 cases with gene amplification by FISH, 67% were positive in the Herceptest (2+ or 3+) vs. 83% with CB11. Of 174 cases negative by FISH, 96% were negative in the Herceptest and 68% with CB11. In conclusion, FISH is the most accurate, reproducible, and precise predictor of HER2 overexpression in routine diagnostic laboratories.


Subject(s)
Breast Neoplasms/genetics , Gene Amplification , Genes, erbB-2/physiology , Transcriptional Activation , Antibodies, Monoclonal/immunology , Autoradiography , Chromosomes, Human, Pair 17/genetics , Confidence Intervals , Female , Frozen Sections , Humans , In Situ Hybridization, Fluorescence , Life Tables , Observer Variation , Predictive Value of Tests , Reagent Kits, Diagnostic
5.
Sci Total Environ ; 265(1-3): 327-42, 2001 Jan 29.
Article in English | MEDLINE | ID: mdl-11227276

ABSTRACT

The Harmonised Monitoring Scheme (HMS) was initiated in 1974 and represents the best-organised source of temporal and spatial data describing water quality for the major mainland rivers of Scotland, England and Wales. This paper presents the first detailed analysis of HMS data for Scotland, and identifies temporal changes in water quality from 1974 to 1995. From a concomitant analysis of catchment land cover characteristics, water quality indices have been linked with potential 'drivers' of change, influencing both point and diffuse sources. Nitrate concentrations between rivers are highly correlated with the amount of arable land, and relationships exist between grassland cover, orthphosphate-P and suspended solids concentrations. Similarly, urban catchments are highly correlated with ammonium-N, orthophosphate-P and suspended solids. Spatial and temporal trends in water quality for the rivers of Scotland are discussed.


Subject(s)
Environmental Monitoring , Water Pollutants/analysis , Agriculture , Fresh Water/analysis , Nitrates/analysis , Phosphates/analysis , Plants , Retrospective Studies , Scotland , Time Factors , Urban Population
6.
Sci Total Environ ; 265(1-3): 51-63, 2001 Jan 29.
Article in English | MEDLINE | ID: mdl-11227282

ABSTRACT

Over large areas of the Scottish uplands anthropogenic sulfur (S) deposition is declining in response to stringent national and European controls on S emissions. At the same time, however, the relative contribution of nitrogenous (N) compounds to the total anthropogenic deposition loading has increased. To investigate the significance of N deposition on the potential acidification of surface waters, national, regional, and catchment databases were developed to assess the relationships between N deposition, soil C/N ratios, land use and surface water NO3 concentrations. National classification schemes for land use and soils were used as only limited empirical data are available at such large spatial scales. Data were screened to eliminate areas where N inputs are dominated by non-atmospheric sources. From these screened datasets, it was apparent that areas with the highest risk of N leaching were situated predominantly in the upland areas of south-west and west Scotland (areas with low soil C/N ratios). At the regional scale, surface-water NO3 concentration in afforested catchments was negatively correlated with soil C/N ratios below 20. This relationship was not evident in moorland catchments, where NO3 leaching was strongly related to N deposition and the loch/catchment ratio, rather than the soil C/N ratio. Temporal trends of regional water quality highlighted as increasing loch NO3 concentrations between 1988 and 1996-1997, presumably reflecting an increase in N deposition, enhanced leaching losses from the terrestrial component of the catchment, or altered in-lake processes. The hydrochemical records for two catchments in NE Scotland (Lochnagar and Allt a Mharcaidh) highlight the importance of within catchment process in controlling the nitrogen response observed in surface waters. The potential mechanisms through which vegetation and soils may modify incoming deposition are discussed.


Subject(s)
Acid Rain , Environmental Monitoring , Nitrogen/analysis , Water Pollutants, Chemical/analysis , Agriculture , Humans , Nitrogen/metabolism , Plants , Scotland , Soil , Water Pollutants, Chemical/metabolism
7.
Hum Mol Genet ; 8(3): 481-92, 1999 Mar.
Article in English | MEDLINE | ID: mdl-9949207

ABSTRACT

The pathogenic mechanisms underlying myotonic dystrophy (DM), which results from a (CTG) n repeat expansion mutation in the 3'-untranslated region (3'-UTR) of the myotonic dystrophy protein kinase gene ( DMPK ), remain obscure. The multisystemic nature and variable expressivity of the symptoms are unlikely to be explained by a defect in this gene alone. However, the location of the DM-associated (CTG) n repeat in the promoter region of SIX5, immediately downstream of DMPK, implicates it as a second candidate with a pathological role in DM. We hypothesize that dysfunction of SIX5, which is homologous to the Drosophila eye development gene sine oculis ( so ), is primarily responsible for the ophthalmic features of DM. We report an expression pattern for SIX5 in the normal adult eye that matches the sites of the ocular pathology in DM. SIX5 transcripts were detected in the adult corneal epithelium and endothelium, lens epithelium, ciliary body epithelia, cellular layers of the retina and the sclera. SIX5 expression was not detected in fetal eyes. We also report a restricted but partially overlapping expression pattern for DMPK transcripts and DMPK protein in normal fetal and adult eyes. DMPK transcripts were detected in fetal eyes and in adult conjunctival and corneal epithelia, uvea, cellular layers of the retina, optic nerve and in the sclera. DMPK protein was detected in the adult retina, conjunctival and ciliary body epithelia and in the smooth muscle of the ciliary body, pupillary sphincter and uveal blood vessels. We propose that the expression patterns of these two genes indicate their relative contribution to the ophthalmological dysfunction seen in DM. Furthermore, the expression of SIX5 and not DMPK in the adult lens implicates a role for SIX5 dysfunction in the development of adult onset cataracts, the most frequently occurring eye phenotype in DM.


Subject(s)
Eye/enzymology , Myotonic Dystrophy/enzymology , Myotonic Dystrophy/genetics , Protein Serine-Threonine Kinases/genetics , Adult , Animals , Base Sequence , Cataract/etiology , Cataract/genetics , DNA Primers/genetics , Eye/pathology , Fetus/enzymology , Gene Expression , Humans , Immunohistochemistry , In Situ Hybridization , Minisatellite Repeats , Mutation , Myotonic Dystrophy/pathology , Myotonin-Protein Kinase , Protein Serine-Threonine Kinases/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Trinucleotide Repeats
8.
Oncogene ; 18(4): 995-1005, 1999 Jan 28.
Article in English | MEDLINE | ID: mdl-10023675

ABSTRACT

The LYL1 gene was first identified upon the molecular characterization of the t(7;9)(q35;p13) translocation associated with some human T-cell acute leukemias (T-ALLs). In adult tissues, LYL1 expression is restricted to hematopoietic cells with the notable exclusion of the T cell lineage. LYL1 encodes a basic helix-loop-helix (bHLH) protein highly related to TAL-1, whose activation is also associated with a high proportion of human T-ALLs. A yeast two-hybrid system was used to identify proteins that specifically interact with LYL1 and might mediate its activities. We found that p105, the precursor of NF-kappaB1 p50, was the major LYL1-interacting protein in this system. The association between LYL1 and p105 was confirmed both in vitro and in vivo in mammalian cells. Biochemical studies indicated that the interaction was mediated by the bHLH motif of LYL1 and the ankyrin-like motifs of p105. Ectopic expression of LYL1 in a human T cell line caused a significant decrease in NF-kappaB-dependent transcription, associated with a reduced level of NF-kappaB1 proteins.


Subject(s)
DNA-Binding Proteins/metabolism , Helix-Loop-Helix Motifs , I-kappa B Proteins , NF-kappa B/metabolism , Neoplasm Proteins/metabolism , Protein Precursors/metabolism , Proto-Oncogene Proteins , Transcription Factors , Basic Helix-Loop-Helix Transcription Factors , Cell Line , DNA, Complementary/genetics , DNA-Binding Proteins/genetics , Glutathione Transferase/metabolism , Humans , Jurkat Cells , K562 Cells , Leukemia-Lymphoma, Adult T-Cell/metabolism , NF-KappaB Inhibitor alpha , NF-kappa B/genetics , NF-kappa B p50 Subunit , Neoplasm Proteins/genetics , Protein Precursors/genetics , T-Cell Acute Lymphocytic Leukemia Protein 1
9.
Liver ; 19(6): 509-18, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10661685

ABSTRACT

AIMS/BACKGROUND: The integrin alpha4beta7 and mucosal addressin cell adhesion molecule-1 (MAdCAM-1) are involved in normal recirculation of lymphocytes between the blood and the tissues of the gastrointestinal tract. In this study we have examined the expression of MAdCAM-1 in human liver. METHODS: MAdCAM-1 expression was determined in archival human liver tissues by immunohistochemistry. RESULTS: While MAdCAM-1 was not detected in normal fetal or adult human liver, expression was observed in association with portal tract inflammation in a variety of liver diseases. Detailed analysis of liver biopsies from patients with hepatitis C showed a positive correlation between the portal/periportal component of the histological activity index (HAI) grade and the presence or absence of MAdCAM-1 expression. CONCLUSION: MAdCAM-1 expression may be important in the recruitment of lymphocytes to the liver during inflammation.


Subject(s)
Hepatitis/metabolism , Immunoglobulins/metabolism , Liver/metabolism , Mucoproteins/metabolism , Receptors, Lymphocyte Homing/metabolism , Animals , Antibody Specificity , Antigens, CD34/metabolism , Binding Sites, Antibody , Cell Adhesion Molecules , Enzyme-Linked Immunosorbent Assay , Fetus/metabolism , Hepatitis/pathology , Humans , Immunoenzyme Techniques , Liver/pathology , Rabbits , Receptors, Complement 3d/metabolism
11.
Environ Pollut ; 99(3): 309-18, 1998.
Article in English | MEDLINE | ID: mdl-15093295

ABSTRACT

A conceptual model of the combined effects of acid deposition and land-use, Model of Acidification of Groundwater In Catchments (MAGIC), was applied to 21 upland sites in the UK Acid Waters Monitoring Network (AWMN) to assess the likely future recovery in response to the latest international agreements controlling anthropogenic sulphur emissions throughout Europe. Future estimates of sulphur deposition were generated by the Hull Acid Rain Model (HARM), based on the agreed reductions outlined in the Second Sulphur Protocol. The results indicate only a limited degree of recovery in surface-water chemistry at all sites over the next 50 years; moreover, a continuing decline in soil base status is predicted to occur at 70% of sites, resulting in longer term reacidification of surface-water at 38% of sites. However, compared with a 'business as usual' scenario the recovery is pronounced, although acidified sites will require further reductions in acidic deposition if recovery to pre-industrial chemical conditions are to be achieved. Furthermore, land-use scenarios at afforested sites suggest that replanting of felled forest will lead to a further increase in acidification. This strengthens the argument that plantation forestry should be avoided in areas considered geologically sensitive to acidic deposition.

12.
J Clin Pathol ; 50(5): 442-4, 1997 May.
Article in English | MEDLINE | ID: mdl-9215133

ABSTRACT

While the cytological features of hepatocellular carcinoma on fine needle aspiration cytology are well described, cases of hepatocellular carcinoma with malignant cells in ascitic fluid and their characteristics are not. A patient is described with cirrhosis resulting from chronic hepatitis B virus infection, ascites, and hepatocellular carcinoma diagnosed by effusion cytology. The malignant cells in the effusion were shown to be positive for alpha fetoprotein using immunocytochemistry, and for human albumin using in situ hybridisation, confirming the diagnosis of hepatocellular carcinoma. Further investigations in a terminally ill patient were thus avoided.


Subject(s)
Albumins/metabolism , Ascitic Fluid/chemistry , Biomarkers, Tumor/metabolism , Carcinoma, Hepatocellular/diagnosis , Liver Neoplasms/diagnosis , Biopsy, Needle , Carcinoma, Hepatocellular/metabolism , Female , Humans , In Situ Hybridization , Liver Neoplasms/metabolism , Middle Aged
13.
Hepatology ; 24(5): 1282-7, 1996 Nov.
Article in English | MEDLINE | ID: mdl-8903411

ABSTRACT

Hepatocyte growth factor (HGF) is mitogenic for hepatocytes and some tumor cell lines. Elevations in plasma HGF levels have been detected in patients with hepatocellular carcinoma (HCC), and it is possible that HGF is involved in the promotion and/or progression of tumor growth. We measured serum and liver tissue HGF levels during chemically induced hepatocarcinogenesis. Wistar rats were given diethylnitrosamine (DEN) in drinking water for 10 weeks with controls receiving drinking water only. Animals were killed at 10, 16, and 19 weeks. Liver HGF levels were determined from immunoblotted protein by scanning densitometry, and serum HGF levels were measured by sandwich enzyme-linked immunosorbent assay (ELISA). HGF was also immunolocalized in fixed liver tissue sections. In DEN-treated animals, at 10 weeks, there was necroinflammation but no dysplasia. Serum HGF was elevated compared with controls (P < .001) but there was no increase in liver HGF. At 16 weeks, there was liver cell dysplasia with minimal necroinflammation; serum and tissue HGF levels were both significantly elevated above controls. At 19 weeks, hepatocellular carcinomas (HCC) were present in five of six DEN-treated animals; liver HGF (P < .05) and serum HGF (P < .001) were both elevated compared with controls. HGF was localized in basement membranes around bile ducts and vessels and some perisinusoidal cells. Increased HGF immunolabeling was observed at 16 and 19 weeks, but dysplastic hepatocytes and tumor cells were HGF-negative. HGF may serve as a growth promoter at early stages during liver tumor development acting through possibly endocrine and paracrine pathways. Recent observations have described HGF as being mitoinhibitory for HCC cell lines; it is possible therefore that the continued up-regulation of HGF in the latter stages of our DEN model may inhibit tumor cell growth, and thus represent a form of antitumor host response.


Subject(s)
Hepatocyte Growth Factor/metabolism , Liver Neoplasms, Experimental/metabolism , Liver/metabolism , Animals , Antibodies, Monoclonal/immunology , Diethylnitrosamine , Female , Hepatocyte Growth Factor/analysis , Liver/drug effects , Liver/pathology , Liver Neoplasms, Experimental/chemically induced , Rats , Rats, Wistar
14.
J Pathol ; 180(1): 71-3, 1996 Sep.
Article in English | MEDLINE | ID: mdl-8943818

ABSTRACT

Most patients with nephroblastoma have high levels of plasma renin and some are hypertensive. Blood pressure falls after removal of the affected kidney, suggesting that nephroblastoma is associated with renin production either by the tumour or by the kidney. In this study, direct evidence was sought of renin gene expression in nephroblastoma using in situ hybridization. Digoxigenin-labelled riboprobes and an immunoperoxidase technique were used to detect cells containing renin mRNA: this showed renin gene expression in 9 out of 12 cases. There were positive cells within metanephric blastema and in occasional neoplastic glomeruloid structures, confirming that in seven cases nephroblastoma tumour cells expressed the renin gene. However, renin gene expression was also demonstrated in perivascular cells of uncertain lineage in seven cases; in five cases there was evidence of renin gene expression in both tumour cells and perivascular cells. The latter finding raises the possibility that some of the cells expressing the renin gene could be stromal cells. It is concluded that nephroblastomas contain cells that express the renin gene and that some are tumour cells, while other perivascular cells may be stromal cells.


Subject(s)
Kidney Neoplasms/enzymology , Renin/metabolism , Wilms Tumor/enzymology , Child , Child, Preschool , Female , Gene Expression , Humans , In Situ Hybridization , Infant , Male , RNA, Messenger/genetics , RNA, Neoplasm/genetics , Renin/genetics
15.
J Hepatol ; 24(4): 385-90, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8738723

ABSTRACT

BACKGROUND/METHODS: Hepatocyte growth factor is thought to be important in stimulating growth of the liver following injury. In this study we have measured serum levels of hepatocyte growth factor together with hepatocyte proliferation in liver biopsies, by detection of the Ki-67 antigen, in 23 patients with alcoholic hepatitis. RESULTS: Serum hepatocyte growth factor was elevated in all patients (median 0.9 ng/ml; range 0.6-7.7 ng/ml; normal < 0.5 ng/ml) and there was a positive correlation between hepatocyte growth factor levels and hepatocyte proliferation in the biopsies. CONCLUSIONS: These results demonstrate that in acute alcoholic hepatitis the liver proliferates in response to injury and suggest that hepatocyte growth factor may be one of the growth factors responsible for this proliferative activity.


Subject(s)
Hepatitis, Alcoholic/blood , Hepatitis, Alcoholic/pathology , Hepatocyte Growth Factor/blood , Liver/pathology , Adult , Aged , Antibodies, Monoclonal , Cell Division , Female , Hepatitis, Alcoholic/physiopathology , Humans , Ki-67 Antigen/analysis , Liver/physiopathology , Liver Function Tests , Male , Middle Aged
16.
Toxicol Pathol ; 23(3): 256-61, 1995.
Article in English | MEDLINE | ID: mdl-7659950

ABSTRACT

Changes in the mRNA and protein expression of renin-secreting cells in the juxtaglomerular apparatus (JGA) were examined in the rat following administration of ZENECA ZD8731, an angiotensin II receptor antagonist. Doses of 0 or 90 mg/kg were administered daily by gavage for 26 wk. JGA hypertrophy was apparent in histological sections. Immunohistochemistry demonstrated an increase in the number of renin-containing cells in both the afferent arterioles and the interlobular arteries. Similarly, renin mRNA expression, demonstrated by in situ hybridization, had extended to more proximal segments of the afferent arterioles and was also present in efferent arterioles and interlobular arteries. In conclusion, JGA hypertrophy occurred as a result of antagonism of the angiotensin II receptor. Associated with JGA hypertrophy was increased expression of both renin and renin mRNA, indicative of stimulated renin synthesis caused by an exaggerated pharmacological response of renin-secreting cells to the loss of feedback inhibition by angiotensin II.


Subject(s)
Angiotensin II/antagonists & inhibitors , Angiotensin II/pharmacology , Angiotensin Receptor Antagonists , Biphenyl Compounds/pharmacology , Juxtaglomerular Apparatus/drug effects , Quinolines/pharmacology , Renin/biosynthesis , Animals , Female , Immunohistochemistry , In Situ Hybridization , Juxtaglomerular Apparatus/metabolism , Juxtaglomerular Apparatus/pathology , Male , Proteins/analysis , RNA, Messenger/analysis , Rats , Rats, Inbred Strains , Renin/chemistry , Renin/genetics
17.
Environ Pollut ; 87(3): 259-66, 1995.
Article in English | MEDLINE | ID: mdl-15091575

ABSTRACT

Rime ice deposition and snow chemistry has been determined over a 4-year period on the summit of Cairngorm Mountain, NE Scotland. The direction of ice deposition reflected the dominant air mass movement over the summit. Sea salt concentrations in the rime ice were approximately 2.5 times greater than in snow deposited over the same period. Excess sulphate concentrations were double, and those of nitrate nearly four times higher. The direction of deposition influenced concentrations of excess sulphate and nitrogen species (nitrate and ammonium) in rime ice. The same directional effect was found in the snow chemistry indicating increased entrapment of pollutants, or a more polluted air mass, when it prevailed from a Southerly or Easterly direction. The potential surface reactions involving gaseous species of S and N may increase the ionic loading to the rime and reflect natural ionic enrichment of the rimed snowpack surface. Because of such phenomena, rime ice is proposed as a further indicator of winter air quality revealing important information on ionic interactions and total deposition flux measurement, especially at high altitudes.

18.
Cell Motil Cytoskeleton ; 28(4): 303-16, 1994.
Article in English | MEDLINE | ID: mdl-7954857

ABSTRACT

Cytochalasin D and dBcAMP cause cultured astrocytes to change from flat cells to retracted process-bearing cells. F-actin was present throughout cells stimulated with dBcAMP for 16 h, whereas cytochalasin D caused F-actin to form massive aggregates at the tips of the cell processes. The two drugs differently regulated the expression of both beta-actin and tropomyosin genes in astrocytes cultured in the presence or absence of serum: dBcAMP caused down-regulation and cytochalasin D caused up-regulation. Northern blot analyses indicated that: (1) serum deprivation halved the concentration of all tropomyosin transcripts (TM-1, TM-2, TM-4, TMBr-1, TMBr-2). Serum induced TM-4 via transcriptional activation, independent of protein synthesis, (2) dBcAMP induced down-regulation of beta-actin (-50%) and tropomyosin transcripts (-35 to 52%) even in the presence of serum. The concentration of profilin mRNA decreased in dBcAMP-reactive astrocytes (-46%). The decrease in beta-actin mRNA concentration was not blocked by cycloheximide, whereas down-regulation of tropomyosin transcripts was completely reversed when protein synthesis was inhibited, and (3) cytochalasin D induced an increase in the concentration of tropomyosin transcripts (+69 to 185%) which was cumulative with serum stimulation. Cytochalasin D induction of both beta-actin and TM-4 operated through transcriptional activation, independent of protein synthesis. The production of all tropomyosin transcripts examined here were strictly coordinated with beta-actin expression in serum-, dBcAMP- and cytochalasin D-treated astrocytes. This indicates that the differential expression of tropomyosin isoforms occurring during astrocyte maturation is due to more complex regulation than that involved in serum- or cAMP-stimulated astrocytes.


Subject(s)
Actins/biosynthesis , Astrocytes/metabolism , Bucladesine/pharmacology , Cytochalasin D/pharmacology , Gene Expression Regulation/drug effects , Tropomyosin/biosynthesis , Actin Cytoskeleton/metabolism , Actins/genetics , Amino Acid Sequence , Animals , Animals, Newborn , Astrocytes/drug effects , Base Sequence , Blood , Cells, Cultured , Culture Media , Cycloheximide/pharmacology , Molecular Sequence Data , RNA, Messenger/biosynthesis , Rats , Tropomyosin/genetics
19.
Histopathology ; 21(4): 335-44, 1992 Oct.
Article in English | MEDLINE | ID: mdl-1398536

ABSTRACT

We have investigated the distribution of type VI collagen in normal human liver obtained from cadaveric renal transplant donors, using a peroxidase-antiperoxidase method for light microscopic visualization, and an immunogold labelling method for ultrastructural localization. The distribution was compared with that of the more abundant interstitial collagen type III, using antibodies to amino terminal procollagen type III. Staining for type VI collagen was identified in Glisson's capsule, in portal tract stroma and within the space of Disse. Perisinusoidal staining showed intra-acinar heterogeneity with the intensity in acinar zones 2 and 3 being greater than in zone 1. Type III collagen was also found in the space of Disse although no significant intra-acinar variation in staining intensity was noted. Immuno-gold labelling for type VI collagen was demonstrated on amorphous or microfilamentous material lying between, and occasionally appearing to interconnect, cross-striated collagen fibrils, whereas labelling for amino terminal procollagen type III was exclusively on fibrils. Intracellular staining for type VI collagen was noted in perisinusoidal (lto) cells. These results confirm that type VI collagen is a ubiquitous constituent of the normal hepatic extracellular matrix and suggest that it may be synthesized by perisinusoidal (lto) cells. The distribution of type VI collagen was also studied in biopsy material from patients with different histological stages of primary biliary cirrhosis. Intense staining was noted around proliferating bile ductules within developing fibrous septa and in established septa of cirrhotic liver. These observations indicate that this 'minor' matrix component may play an important role in hepatic fibrogenesis.


Subject(s)
Collagen/analysis , Liver Cirrhosis, Biliary/metabolism , Liver/chemistry , Chronic Disease , Humans , Immunoenzyme Techniques , Liver/cytology , Liver Cirrhosis, Biliary/pathology , Microscopy, Immunoelectron
20.
Aust N Z J Ophthalmol ; 20(2): 133-6, 1992 May.
Article in English | MEDLINE | ID: mdl-1389131

ABSTRACT

Complete return of function has been obtained following neurosurgical repair of a trochlear nerve inadvertently divided during the clipping of a basilar tip aneurysm. To date this is the second case reported in the literature. The technique of repair and the method of recording the return of function is discussed.


Subject(s)
Trochlear Nerve Injuries , Trochlear Nerve/surgery , Adult , Anastomosis, Surgical , Basilar Artery/surgery , Humans , Intracranial Aneurysm/surgery , Intraoperative Complications , Male , Nerve Regeneration/physiology , Treatment Outcome , Trochlear Nerve/physiology , Visual Fields
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