| 1. |
- Feridani, Amir, et al.
(författare)
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Combined flow cytometry and confocal laser scanning microscopy for evaluation of BR96 antibody cancer cell targeting and internalization.
- 2007
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Ingår i: Cytometry Part A. - : Wiley. - 1552-4930 .- 1552-4922. ; 71A:6, s. 361-370
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Tidskriftsartikel (refereegranskat)abstract
- Background: Monoclonal antibodies (mAb) are important tools in the management of tumor disease, and the discovery of antibodies with both specific cancer cell targeting and capacity to enter the cells by internalization are critical to improve the therapeutic efficacy. Method: Antibody cancer cell targeting and internalization properties of fluoroscein-conjugated mAb made against Lewis Y (BR96) were evaluated quantitatively and qualitatively by means of flow cytometry (FCM) and confocal laser scanning microscopy (CLSM), respectively, on cells from a rat tumor cell line (BN7005-H1D2). Results: The study demonstrated a specific binding of BR96 to LewisY (LeY) located in the cell membrane and as BR96/LeY immunocomplexes (BR96/LeY) internalized into the cytoplasm. BR96/LeY was internalized into about 15% of the cells, usually distributed throughout the cytoplasm, but also located close to the nuclei. Cytotoxic effects by BR96 were indicated, and CLSM visualized subpopulations containing cells with bound or internalized BR96/LeY that possessed morphologically pyknotic nuclei and disrupted DNA. Conclusion: The spatial-temporal pattern by BR96 cell targeting and internalization processes of BR96/LeY into the cancer cells expressing LeY was demonstrated by FCM and CLSM. Used together, the FCM and CLSM techniques provide a valuable tool for preclinical analyses of antibody targeting and their capacities as carriers of cytotoxic conjugates for the use in cancer therapy.
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| 2. |
- Odenlund, Malin, et al.
(författare)
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Polyamine synthesis inhibition induces S phase cell cycle arrest in vascular smooth muscle cells.
- 2009
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Ingår i: Amino Acids. - : Springer Science and Business Media LLC. - 0939-4451 .- 1438-2199. ; 36, s. 273-282
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Tidskriftsartikel (refereegranskat)abstract
- Polyamines are important for cell growth and proliferation and they are formed from arginine and ornithine via arginase and ornithine decarboxylase (ODC). Arginine may alternatively be metabolised to NO via NO synthase. Here we study if vascular smooth muscle cell proliferation can be reversed by polyamine synthesis inhibitors and investigate their mechanism of action. Cell proliferation was assessed in cultured vascular smooth muscle A7r5 cells and in endothelium-denuded rat arterial rings by measuring [(3)H]-thymidine incorporation and by cell counting. Cell cycle phase distribution was determined by flow cytometry and polyamines by HPLC. Protein expression was determined by Western blotting. The ODC inhibitor DFMO (1-10 mM) reduced polyamine concentration and attenuated proliferation in A7r5 cells and rat tail artery. DFMO accumulated cells in S phase of the cell cycle and reduced cyclin A expression. DFMO had no effect on cell viability and apoptosis as assessed by fluorescence microscopy. Polyamine concentration and cellular proliferation were not affected by the arginase inhibitor NOHA (100-200 muM) and the NO synthase inhibitor L: -NAME (100 muM). Lack of effect of NOHA was reflected by absence of arginase expression. Polyamine synthesis inhibition attenuates vascular smooth muscle cell proliferation by reducing DNA synthesis and accumulation of cells in S phase, and may be a useful approach to prevent vascular smooth muscle cell proliferation in cardiovascular diseases.
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| 3. |
- Eaton, Jennifer L., et al.
(författare)
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Ontogeny of vasotocin-expressing cells in zebrafish: Selective requirement for the transcriptional regulators orthopedia and single-minded 1 in the preoptic area
- 2008
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Ingår i: Developmental Dynamics. - : Wiley. - 1097-0177 .- 1058-8388. ; 237:4, s. 995-1005
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Tidskriftsartikel (refereegranskat)abstract
- The neurohypophysial peptide arginine vasotocin, and its mammalian ortholog arginine vasopressin, influence a wide range of physiological and behavioral responses, including aspects of sexual and social behaviors, osmoregulation, stress response, metabolism, blood pressure, and circadian rhythms. Here, we demonstrate that, in zebrafish (Danio rerio), the vasotocin precursor gene arginine vasotocin-neurophysin (avt) is expressed in two domains in the developing embryo: the dorsal preoptic area and the ventral hypothalamus. In the dorsal preoptic area, avt-expressing cells are intermingled with isotocin-neurophysin (ist) -expressing cells, and these neurons project to the neurohypophysis (posterior pituitary). In the dorsal preoptic area, the transcriptional regulators orthopedia b (otpb) and simple-minded 1 (siml) are required for expression of both avt and ist. In contrast, olp and siml are not required for avt expression in the ventral hypothalamus. Thus, the development of these two avt expression domains is influenced by separate gene regulatory networks.
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| 4. |
- Ebbesson, LE, et al.
(författare)
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Nitric oxide synthase in the gill of Atlantic salmon: colocalization with and inhibition of Na+,K+-ATPase
- 2005
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Ingår i: Journal of Experimental Biology. - : The Company of Biologists. - 1477-9145 .- 0022-0949. ; 208:6, s. 1011-1017
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Tidskriftsartikel (refereegranskat)abstract
- We investigated the relationship between nitric oxide (NO) and Na+,K+-ATPase (NKA) in the gill of anadromous Atlantic salmon. Cells containing NO-producing enzymes were revealed by means of nitric oxide synthase (NOS) immunocytochemistry and nicotinamide adenine dinucleotide phosphate diaphorase (NADPHd) histochernistry, which can be used as an indicator of NOS activity, i.e. NO production. Antibodies against the two constitutive NOS isoforms, neuronal and endothelial NOS, both produced immunoreactivity restricted to large cells at the base and along the secondary lamellae. NADPHd-positive cells showed a corresponding distribution. Antibodies against the inducible NOS isoform only labeled small cells located deep in the filament. Using in situ hybridization and NKA immunoreactivity, cells expressing Na+,K+-ATPase alpha-subunit mRNA were found to have a similar distribution to the NOS cells. Double labeling for NOS immunoreactivity and NKA cc-subunit mRNA revealed cellular colocalization of NKA alpha-subunit mRNA and nNOS protein in putative chloride cells at the base of the lamellae and interlamellar space. Along the lamellae, some NOS- or NKA-immunoreactive cells possessed a relatively lower expression of NKA a-subunit mRNA in smolts. A clear increase in NADPHd staining in the gill was demonstrated from parr to smolt. The regulatory role of NO on gill NKA activity was studied in vitro using sodium nitroprusside (SNP; 1 mmol l(-1)) and PAPA-NONOate (NOC-15; 0.5 mmol l(-1)) as NO donors. Both SNP and NOC-15 inhibited gill NKA activity by 30% when compared to controls. The study shows that NO systems are abundant in the gill of Atlantic salmon, that NO may be produced preferentially by a constitutive NOS isoform, and suggests that NO influence on gill functions is mediated via intracellular, possibly both auto/paracrine, inhibition of Na+,K+-ATPase activity in chloride cells. Furthermore, the increase in NADPHd in the gill during smoltification suggests a regulatory role of NO in the attenuation of the smoltification-related increase in Na+,K+-ATPase activity prior to entering seawater.
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| 5. |
- Ebbesson, Lars O. E., et al.
(författare)
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Exposure to continuous light disrupts retinal innervation of the preoptic nucleus during parr-smolt transformation in Atlantic salmon
- 2007
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Ingår i: Aquaculture. - : Elsevier BV. - 0044-8486 .- 1873-5622. ; 273:2-3, s. 345-349
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Konferensbidrag (refereegranskat)abstract
- High quality salmon smolts are essential for aquaculture, enhancement programs and wild populations. However, intensification of aquaculture smolt production and changes in natural habitats can cause sub-optimal environmental conditions, which may result in poor smolt quality. The salmon brain, as the integrator of environmental information, plays a focal role in relaying this information through the light-brain-pituitary axis, which includes retinal and pineal innervation of the hypothalamus. Here we investigated the effect of rearing juvenile Atlantic salmon, Salmo salar, under constant light (LL) on optic nerve fiber growth into the hypothalamus. This was compared with the normal increased fiber growth in fish reared under a simulated-natural photoperiod (LDN). Parr were sampled from the LDN group in February and from the LDN and LL groups in May (peak smolt status for the LDN group). Retinohypothalamic projections to the preoptic area were traced using 1, 1'-dioctadecyl-3,3, 3,3-tetramethylindocarbocyanine perchlorate (DiI) and confocal laser scanning microscopy. Data showed that parr exposed to LL did not develop the same extensive retinal innervation to the preoptic nucleus (NPO) observed in control salmon smolts raised under LDN. Since the cells in NPO are central pituitary regulatory neurones, the increased retinohypothalamic innervation during normal smoltification may be responsible for the increased endocrine response to photoperiod information. The deprivation of photoperiod information, during continuous light exposure, may inhibit the natural developmental program to proceed during the parr-smolt transformation. (C) 2007 Elsevier B.V. All rights reserved.
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| 6. |
- Ekström, Ulf, et al.
(författare)
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Internalization of cystatin C in human cell lines.
- 2008
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Ingår i: The FEBS Journal. - : Wiley. - 1742-464X. ; Aug 9, s. 4571-4582
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Tidskriftsartikel (refereegranskat)abstract
- Altered protease activity is considered important for tumour invasion and metastasis, processes in which the cysteine proteases cathepsin B and L are involved. Their natural inhibitor cystatin C is a secreted protein, suggesting that it functions to control extracellular protease activity. Because cystatins added to cell cultures can inhibit polio, herpes simplex and coronavirus replication, which are intracellular processes, the internalization and intracellular regulation of cysteine proteases by cystatin C should be considered. The extension, mechanism and biological importance of this hypothetical process are unknown. We investigated whether internalization of cystatin C occurs in a set of human cell lines. Demonstrated by flow cytometry and confocal microscopy, A-431, MCF-7, MDA-MB-453, MDA-MB-468 and Capan-1 cells internalized fluorophore-conjugated cystatin C when exposed to physiological concentrations (1 mum). During cystatin C incubation, intracellular cystatin C increased after 5 min and accumulated for at least 6 h, reaching four to six times the baseline level. Western blotting showed that the internalized inhibitor was not degraded. It was functionally intact and extracts of cells exposed to cystatin C showed a higher capacity to inhibit papain and cathepsin B than control cells (decrease in enzyme activity of 34% and 37%, respectively). The uptake of labelled cystatin C was inhibited by unlabelled inhibitor, suggesting a specific pathway for the internalization. We conclude that the cysteine protease inhibitor cystatin C is internalized in significant quantities in various cancer cell lines. This is a potentially important physiological phenomenon not previously described for this group of inhibitors.
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| 7. |
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| 8. |
- Holmqvist, Claes, et al.
(författare)
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A flexible approach for modelling flow in multi-component blade formers
- 2006
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Ingår i: Nordic Pulp & Paper Research Journal. - 0283-2631 .- 2000-0669. ; 21:1, s. 73-81
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Tidskriftsartikel (refereegranskat)abstract
- The internal structure of the fibre network constituting a paper is to a dominating extent determined in the forming zone of the paper machine. In this article we present a method for modelling the pressure distributions in blade forming sections, which is commonly considered to be a key quantity of the process. The ambition is to obtain a tool by which the interaction between the different components of blade sections can be studied. It is achieved by defining modules out of which arbitrary sections can be constructed. The modules are solved independently and matched to each other iteratively Keeping the interface between the modules simple provides great flexibility in the modelling. By virtue of a slenderness assumption, the equations governing each module can be reduced to one-dimensional form, hence limiting the computational work and permitting systems of many components to be studied. Dimensionless numbers defining the problem are identified, and the magnitude of the nonlinear effects are estimated. Simulations are presented that illustrate the potential of the method.
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| 9. |
- Laskar, Pia, 1956-
(författare)
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Ett bidrag till heterosexualitetens historia : Kön, sexualitet och njutningsnormer i sexhandböcker 1800 - 1920
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis examines and analyses Swedish sex manuals written for the most part by doctors between 1800 and 1920. The study focuses on constructions of gender, sexuality and norms for pleasure, and investigates how these processes change over time. A fundamental question raised in the study concerns the descriptions of sexual union between the binary opposed genders and how these descriptions are subsequently connected to medical and scientific ideas during the relevant period. By specifying and drawing attention to these issues, the study makes a contribution to the history of heterosexuality. Special attention is given to sex manuals written by women and published at the turn of the century in 1900.The construction of norms in the sex manuals becomes evident, partly through descriptions of desirable, moderate, sexual behaviour with reference to health, reason, cultural progress and the maximisation of sexual pleasure, and partly through the presentation of deterrents and counter images referring to abnormal, primitive and degenerate genders and sexualities. The construction of a European, middle class gender and sexuality ideal is made apparent in that the norms are also linked to the working class, domestic minorities and other “races”. I call the positive normatisation of heterosexual intercourse an “ideology of pleasure”.According to descriptions in the sex manuals, the boundaries between the opposed genders are often fluid. Therefore the heterosexual union of opposed genders with binary defined sexualities becomes an unstable construction requiring constant stabilisation. During the second half of the 19th Century, when the criterion of reproduction diminished as the defining feature for reciprocal and loving sexual pleasure, the norm for heterosexual pleasure became stabilised by virtue of new arguments. These included the use of strong deterrents against same-gendered sexual activities or masturbation.By juxtaposing the connections between deterrents and taboos against deviant genders and sexualities with descriptions of the division and heterosexual union of the two genders, this investigation makes an empirical contribution to the feminist analysis of the intersection between gender, class and ethnicity in the construction of a heterosexual norm.
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| 10. |
- Nielsen, Henrietta, et al.
(författare)
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Binding and Uptake of A beta 1-42 by Primary Human Astrocytes In Vitro
- 2009
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Ingår i: GLIA. - : Wiley. - 1098-1136 .- 0894-1491. ; 57:9, s. 978-988
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Tidskriftsartikel (refereegranskat)abstract
- Clearance of the amyloid-P peptide (A beta) as a remedy for Alzheimer's disease (AD) is a major target in on-going clinical trials. In vitro studies confirmed that A beta is taken up by rodent astrocytes, but knowledge on human astrocyte-mediated A beta clearance is sparse. Therefore, by means of flow cytometry and confocal laser scanning microscopy (CLSM), we evaluated the binding and internalization of A beta 1-42 by primary human fetal astrocytes and adult astrocytes, isolated from nondemented subjects (n = 8) and AD subjects (n = 6). Furthermore, we analyzed whether alpha 1-antichymotrypsin (ACT), which is found in amyloid plaques and can influence A beta fibrillogenesis, affects the A beta uptake by human astrocytes. Upon over night exposure of astrocytes to FAM-labeled A beta 1-42 (10 mu M) preparations, (80.7 +/- 17.7)% fetal and (52.9 +/- 20.9)% adult A beta-positive astrocytes (P = 0.018) were observed. No significant difference was found in A beta 1-42 uptake between AD and non-AD astrocytes, and no influence of ApoE genotype on A beta 1-42 uptake was observed in any group. There was no difference in the percentage of A beta-positive cells upon exposure to A beta 1-42 (10 mu M) combined with ACT (1,000:1, 100:1, and 10:1 molar ratio), versus A beta 1-42 alone. CLSM revealed binding of A beta 1-42 to the cellular surfaces and cellular internalization of smaller A beta 1-42 fragments. Under these conditions, there was no increase in cellular release of the proinflammatory chemokine monocyte-chemoattractant protein 1, as compared with nontreated control astrocytes. Thus, primary human astrocytes derived from different sources can bind and internalize A beta 1-42, and fetal astrocytes were more efficient in A beta 1-42 uptake than adult astrocytes. (C) 2008 Wiley-Liss, Inc.
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