14 research outputs found
Kyssta grodor : En studie av uppköpta svenska börsnoterade företag
We have examined the stock development of acquired listed Swedish companies - from the years 1995 to 2005 - upon the official publication of the bid. Thereafter we further investigated if there is a difference in the stock development between companies that are acquired by foreign investorscompared to Swedish investors. Also, a difference in the stock development could be due to the acquired firms’ industry classification and its company size, which we have been looking at. In order to study the bid news impact on the share price, a quantitative study in the form of an event study has been done, where the abnormal return associated with the news has been measured. The research shows that there indeed is a difference between companies acquired by foreign investors versus Swedish. As for industry classification, we find one out of six different industries standing out. The comparisons within the remaining industries shows similar results to the comparison of Swedish and foreign companies we mentioned before. In terms of company size,larger companies have shown a lower cumulative abnormal return compared to smaller companies. Furthermore the research also shows that larger the acquired companies are smaller the difference is in the cumulative abnormal return.Vi har undersökt aktieutvecklingen hos uppköpta börsnoterade svenska företag, mellan 1995 till 2005, vid offentliggörandet av budet. Därefter undersöker vi även om det finns en skillnad i aktieutvecklingen mellan företag som blir uppköpta av utländska aktörer jämfört med de som blir uppköpta av svenska. Vidare skulle en visad skillnad i aktieutvecklingen kunna bero på de uppköpta företagens branschtillhörighet respektive företagens storlek, vilket vi har tittar närmare på.För att studera budnyhetens inverkan på börskursen har en kvantitativ undersökning i form av en event studie gjorts, där den abnormala avkastningen i samband med budnyheten mätts.Resultatet visar att det finns en skillnad mellan företag som blivit uppköpta av utländska aktörer och svenska. Vad gäller branschindelningen finner vi en bransch som utmärker sig gentemot de andra. Resterande branscher sammanfaller med jämförelsen av svenska och utländska företag. Storleksmässigt visade större företag allmänt en lägre kumulativ avkastning än mindre. Vidare är skillnaden mindre, mellan företag köpta av svenska aktörer och utländska, ju större företagen är
Nortriptyline induces mitochondria and death receptor-mediated apoptosis in bladder cancer cells and inhibits bladder tumor growth in vivo
Nortriptyline (NTP), an antidepressant, has antitumor effects on some human cancer cells, but its effect on human bladder cancer cells is not known. In this study, we used a cell viability assay to demonstrate that NTP is cytotoxic to human TCCSUP and mouse MBT-2 bladder cancer cells in a concentration and time-dependent manner. We also performed cell cycle analysis, annexin V and mitochondrial membrane potential assays, and Western blot analysis to show that NTP inhibits cell growth in these cells by inducing both mitochondria-mediated and death receptor-mediated apoptosis. Specifically, NTP increases the expression of Fas, FasL, FADD, Bax, Bak, and cleaved forms of caspase-3, caspase-8, caspase-9, and poly(ADP-ribose) polymerase. In addition, NTP decreases the expression of Bcl-2, Bcl-xL, BH3 interacting domain death agonist, X-linked inhibitor of apoptosis protein, and survivin. Furthermore, NTP-induced apoptosis is associated with reactive oxygen species (ROS) production, which can be reduced by antioxidants, such as N-acetyl-L-cysteine. Finally, we showed that NTP suppresses tumor growth in mice inoculated with MBT-2 cells. Collectively, our results suggest that NTP induces both intrinsic and extrinsic apoptosis in human and mouse bladder cancer cells and that it may be a clinically useful chemotherapeutic agent for bladder cancer in humans
The Effect of Sertoli Cells on Xenotransplantation and Allotransplantation of Ventral Mesencephalic Tissue in a Rat Model of Parkinson’s Disease
Intra-striatal transplantation of fetal ventral mesencephalic (VM) tissue has a therapeutic effect on patients with Parkinson’s disease (PD). Sertoli cells (SCs) possess immune-modulatory properties that benefit transplantation. We hypothesized that co-graft of SCs with VM tissue can attenuate rejection. Hemi-parkinsonian rats were generated by injecting 6-hydroxydopamine into the right medial forebrain bundle of Sprague Dawley (SD) rats. The rats were then intrastriatally transplanted with VM tissue from rats or pigs (rVM or pVM), with/without a co-graft of SCs (rVM+SCs or pVM+SCs). Recovery of dopaminergic function and survival of the grafts were evaluated using the apomorphine-induced rotation test and small animal-positron emission tomography (PET) coupled with [18F] DOPA or [18F] FE-PE2I, respectively. Immunohistochemistry (IHC) examination was used to determine the survival of the grafted dopaminergic neurons in the striatum and to investigate immune-modulatory effects of SCs. The results showed that the rVM+SCs and pVM+SCs groups had significantly improved drug-induced rotational behavior compared with the VM alone groups. PET revealed a significant increase in specific uptake ratios (SURs) of [18F] DOPA and [18F] FE-PE2I in the grafted striatum of the rVM+SCs and pVM+SCs groups as compared to that of the rVM and pVM groups. SC and VM tissue co-graft led to better dopaminergic (DA) cell survival. The co-grafted groups exhibited lower populations of T-cells and activated microglia compared to the groups without SCs. Our results suggest that co-graft of SCs benefit both xeno- and allo-transplantation of VM tissue in a PD rat model. Use of SCs enhanced the survival of the grafted dopaminergic neurons and improved functional recovery. The enhancement may in part be attributable to the immune-modulatory properties of SCs. In addition, [18F]DOPA and [18F]FE-PE2I coupled with PET may provide a feasible method for in vivo evaluation of the functional integrity of the grafted DA cell in parkinsonian rats
Guidelines for the use and interpretation of assays for monitoring autophagy
In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field