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Background and objectives Desmoid tumors are soft-tissue tumors originating from myofibroblasts with a tendency to recur after surgery. High expression of proliferation markers is associated with shortened progression-free and/or overall survival in many neoplasms, including soft-tissue sarcomas. We investigated the prognostic role of cyclin A and Ki67 in desmoid tumors by immunohistochemistry. Methods The study included 76 patients with desmoid tumor operated at Helsinki University Hospital between 1987 and 2011. A tissue micro array (TMA) was constructed and the TMA sections were immunostained with cyclin A and Ki67 antibodies. A computer-assisted image analysis was performed. Results Cyclin A expression was evaluable in 74 and Ki67 in 70 patients. Cyclin A immunopositivity varied from 0% to 9.9%, with a mean of 1.9%. Cyclin A expression correlated significantly with Ki67. Cyclin A expression was associated with recurrence-free survival (HR 1.9, 95% CI = 1.1-3.2, P = .02), as were positive margin (HR 6.0, 95% CI = 1.6-22.5, P = .008) and extremity location (HR 5.3, 95% CI = 1.7-16.8, P = 0.005). Ki67 immunopositivity varied from 0.33% to 13.8%, with a mean of 4.6%, but had no significant prognostic impact (HR 1.1, P = .2). Conclusions Our study indicates that cyclin A may be a new prognostic biomarker in surgically treated desmoid tumors.

Aim To gain a deeper understanding of community nurses' experiences of ethical problems in end-of-life care in the patient′s own home. Method Ten female nurses from five different communities with experience of end-of-life care were interviewed. A hermeneutic approach inspired by Gadamer was used to analyse the qualitative data from the interviews. Findings In the first step of interpretation, two themes emerged: Uncomfortable feelings and Lack of cooperation and in the second step, one theme Lack of security emerged. Finally, the overall interpretation revealed the theme Feelings of loss of control in end-of-life care in the patient's own home. Conclusion The nurses exhibited commitment and a desire to do good when caring for patients in the end-of-life phase, even if they sometimes experienced feelings of lack of control. This implies that, when confronted with care-related issues, they have the power to both act and react. This study aimed to increase understanding of ethical problems that arise in end-of-life care in the patient's own home and revealed the need to take the patients', relatives' and nurses' perspectives on health and suffering into consideration to ensure good end-of-life home care.

In non-small cell lung carcinoma (NSCLC) there are gender differences. The female gender is associated with more adenocarcinomas (ADCA), among both smokers and non-smokers compared to men. Women wi ...

The precise description of the gravitropic curvature response of plants is often difficult due to the presence of gravity when the response is recorded. Therefore, unambiguous results on the gravitropic reactions in differents segments of coleoptiles, the participation of auxin transport in the curvature development and the reactions to hypogravity stimulations can only be achieved in weightlessness. To answer these questions, curvatures of Avena coleoptiles at different distances from the apex were studied after transverse, hypogravity stimulations. The experiments were conducted in Spacelab on the Shuttle in earth orbit. Test plants were cultivated on 1.0 g-centrifuges in Spacelab. The stimulation accelerations, were between 0.1 and 1.0 g, and duration varied between 2 and 130 min. All plant responses were recorded in weightlessness by a video cassette recorder for analysis. The gravitropic curvature started almost simultaneously in apical segments, and occurred later in the basal ones. After maximum response, the curvature in the top segments showed a clear autotropic reaction, that was not seen in the basal segments. Initial wrong-way curvatures were recorded in the basal part of the coleoptiles at several g-levels. The further down along the coleoptile, the later the occurrence of the maximum gravitropic curvature of each segment. For example, after a stimulus of 25 g min the maxima appeared to travel down the coleoptile with a speed of about 50 mm h−1 in the upper and 20 mm h−1 in the lower part of the coleoptiles. It is concluded that the basipetal auxin transport can contribute only marginally to the gravitropic curvature pattern due to its much lower transport rate. Local reactions control the curvature pattern in each segment (even if the basipetal auxin transport must add to the reactions). Extrapolations from stimulus response data curves allowed some determinations of threshold stimulation times for different segments along the coleoptiles. Data for the individual segments along the coleoptiles were not at variance with the reciprocity law.

The acetylation state of histones can influence transcription. Acetylation, carried out by acetyltransferases such as CBP/p300 and P/CAF, is commonly associated with transcriptional stimulation, whereas deacetylation, mediated by the three known human deacetylases HDAC1, 2 and 3, causes transcriptional repression. The known human deacetylases represent a single family and are homologues of the yeast RPD3 deacetylase. Here we identify and characterize HDAC4, a representative of a new human histone deacetylase family, which is homologous to the yeast HDA1 deacetylase. We show that HDAC4, unlike other deacetylases, shuttles between the nucleus and the cytoplasm in a process involving active nuclear export. In the nucleus, HDAC4 associates with the myocyte enhancer factor MEF2A. Binding of HDAC4 to MEF2A results in the repression of MEF2A transcriptional activation, a function that requires the deacetylase domain of HDAC4. These results identify MEF2A as a nuclear target for HDAC4-mediated repression and suggests that compartmentalization may be a novel mechanism for controlling the nuclear activity of this new family of deacetylases.

The gas3/PMP22 gene product is a dual function protein, involved in both peripheral nerve myelination and cell proliferation. gas 3/PMP22 is highly expressed in myelinating Schwann cells and is required for normal PNS development. In addition, a more general function for gas3 is suggested by its expression in non-neural tissues and upregulation by growth arrest in cultured rodent fibroblasts. In the present work, the expression of the gas3 gene has been studied in human fibroblasts. We have confirmed that gas3 mRNA is upregulated when cells are serum starved or grown to high cell density (G0 arrest). When quiescent cells were stimulated by serum or platelet-derived growth factor-BB (PDGF-BB), gas3 mRNA was down regulated. In contrast, we found that the expression of gas3 mRNA was neither upregulated in senescent cells nor in cells arrested in G1 using Lovastatin. Thus, high expression of gas3 is not related to growth inhibition in general, but more probably to the G0 growth arrest state. Furthermore, we found that in two malignant fibrous histiocytoma cell lines, gas3 expression was lower than in normal fibroblasts, suggesting an altered regulation of the gas3 gene in transformed cells.

In eukaryotes, mitosis is initiated by M phase promoting factor (MPF), composed of B-type cyclins and their partner protein kinase, CDK1. In animal cells, MPF is cytoplasmic in interphase and is translocated into the nucleus after mitosis has begun, after which it associates with the mitotic apparatus until the cyclins are degraded in anaphase. We have used a fusion protein between human cyclin B1 and green fluorescent protein (GFP) to study this dynamic behaviour in real time, in living cells. We found that when we injected cyclin B1-GFP, or cyclin B1-GFP bound to CDK1 (i.e. MPF), into interphase nuclei it is rapidly exported into the cytoplasm. Cyclin B1 nuclear export is blocked by leptomycin B, an inhibitor of the recently identified export factor, exportin 1 (CRM1). The nuclear export of MPF is mediated by a nuclear export sequence in cyclin B1, and an export-defective cyclin B1 accumulates in interphase nuclei. Therefore, during interphase MPF constantly shuttles between the nucleus and the cytoplasm, but the bulk of MPF is retained in the cytoplasm by rapid nuclear export. We found that a cyclin mutant with a defective nuclear export signal does not enhance the premature mitosis caused by interfering with the regulatory phosphorylation of CDK1, but is more sensitive to inhibition by the Wee1 kinase.

The dynamics of root growth was studied in weightlessness. In the absence of the gravitropic reference direction during weightlessness, root movements could be controlled by spontaneous growth processes, without any corrective growth induced by the gravitropic system. If truly random of nature, the bending behavior should follow so-called 'random walk' mathematics during weightlessness. Predictions from this hypothesis were critically tested. In a Spacelab ESA-experiment, denoted RANDOM and carried out during the IML-2 Shuttle flight in July 1994, the growth of garden cress (Lepidium sativum) roots was followed by time lapse photography at 1-h intervals. The growth pattern was recorded for about 20 h. Root growth was significantly smaller in weightlessness as compared to gravity (control) conditions. It was found that the roots performed spontaneous movements in weightlessness. The average direction of deviation of the plants consistently stayed equal to zero, despite these spontaneous movements. The average squared deviation increased linearly with time as predicted theoretically (but only for 8-10 h). Autocorrelation calculations showed that bendings of the roots, as determined from the 1-h photographs, were uncorrelated after about a 2-h interval. It is concluded that random processes play an important role in root growth. Predictions from a random walk hypothesis as to the growth dynamics could explain parts of the growth patterns recorded. This test of the hypothesis required microgravity conditions as provided for in a space experiment.

Experiments were undertaken to determine if the reciprocity rule is valid for gravitropic responses of oat coleoptiles in the acceleration region below 1 g. The rule predicts that the gravitropic response should be proportional to the product of the applied acceleration and the stimulation time. Seedlings were cultivated on 1 g centrifuges and transferred to test centrifuges to apply a transverse g-stimulation. Since responses occurred in microgravity, the uncertainties about the validity of clinostat simulation of weightlessness was avoided. Plants at two stages of coleoptile development were tested. Plant responses were obtained using time-lapse video recordings that were analyzed after the flight. Stimulus intensities and durations were varied and ranged from 0.1 to 1.0 g and from 2 to 130 min, respectively. For threshold g-doses the reciprocity rule was obeyed. The threshold dose was of the order of 55 g s and 120 g s, respectively, for two groups of plants investigated. Reciprocity was studied also at bending responses which are from just above the detectable level to about 10 degrees. The validity of the rule could not be confirmed for higher g-doses, chiefly because the data were more variable. It was investigated whether the uniformity of the overall response data increased when the gravitropic dose was defined as (gm x t) with m-values different from unity. This was not the case and the reciprocity concept is, therefore, valid also in the hypogravity region. The concept of gravitropic dose, the product of the transverse acceleration and the stimulation time, is also well-defined in the acceleration region studied. With the same hardware, tests were done on earth where responses occurred on clinostats. The results did not contradict the reciprocity rule but scatter in the data was large.

In a spaceflight experiment, autotropism by oat (Avena sativa L.) coleoptiles following gravitropic responses was prominent in weightlessness: counter-reactions led to the straightening of the curved coleoptiles. This was not the case during clinorotation on earth. The autotropic reactions appeared to be related to the stimulus received during the stimulus period, i.e. the greater the response the greater the autotropic counter-reaction. Previous models of the gravitropic system which predicted that coleoptiles would not straighten in weightlessness are disproved. A modification to one of the models is proposed which includes the autotropic response observed in spaceflight. The nature of the counter-reactions in the absence of gravitropic stimulation is discussed.

We have previously found that transforming growth factor-beta 1 (TGF-beta 1) inhibits the mitogenic activity of platelet-derived growth factor (PDGF) in cultures of human neonatal fibroblasts in a density-dependent fashion. In the present investigation we determined the effect of TGF-beta 1 on the PDGF alpha-receptor, which binds all PDGF isoforms, as well as on the beta-receptor, which binds only PDGF-BB with high affinity. We found that the inhibitory effect of TGF-beta 1 on PDGF-AA-induced mitogenesis was density-dependent; when dense cell cultures were preincubated with TGF-beta 1, there was an complete inhibition of 3H-thymidine incorporation, whereas the effect was less in sparse cultures. A similar density-dependent effect of TGF-beta 1 was seen in PDGF-BB treated cells, although less pronounced. The binding of 125I-labeled PDGF-AA and PDGF-BB to the alpha-receptor was significantly reduced after treatment with TGF-beta 1 in dense cultures, whereas the sparse cultures were less affected. A decrease of alpha-receptor mRNA was also seen. The levels of beta-receptor protein and mRNA were unaffected. We conclude that the growth inhibitory effect of TGF-beta 1 is cell density-dependent and involves down-regulation of PDGF alpha-receptors.

Dark-grown oat seedlings depart from the expected vertical orientation, suggesting that the coleoptile is less responsive to the lateral component of a gravitational stimulus than would be expected. This phenomenon was studied by investigating the gravitropic curvatures of oat (Avena sativa L. cv. Seger) coleoptiles at 10g and over a range of longitudinally applied centripetal accelerations up to 19·4g. In most experiments, the plants were grown and observed at a particular g-level throughout the experiment. Time-lapse video recordings permitted studies of the scatter, measured as the variability of the plants' angle from the vertical (or root mean square value, RMS). The coleoptiles' heights at the end of the experiments were not significantly altered under the centrifugation. Scatter increased with plant age and decreased with increasing g. It decreased in an almost linear fashion as a function of the logarithm of the g-acceleration. In a series of experiments, the g-level was changed from 10g to a higher test g-acceleration. The scatter was then reduced within half an hour after the g-transition. It is pointed out that the experiments confirm that the scatter is g-related but that it was not predicted quantitatively by present theories of the oat coleoptile's gravitropic response kinematics.

The tissue distribution of mRNA of alcohol dehydrogenases of classes I, II and III, and sorbitol dehydrogenase, was studied. mRNA from 19 different rat tissues was purified and analyzed by Northern blots, utilizing cDNA probes specific for the four dehydrogenases. Class-I alcohol-dehydrogenase mRNA was shown to be of widespread occurrence, detectable in all tissues including brain, but with pronounced differences in amounts. Hybridization revealed the pattern of occurrence of class-II alcohol-dehydrogenase mRNA to be unique, with transcripts only in the liver, duodenum, kidney, stomach, spleen and testis. Abundant levels of class-III alcohol-dehydrogenase (glutathione-dependent formaldehyde dehydrogenase) mRNA were present in all tissues analyzed, reflecting the general need for scavenging of formaldehyde in physiological cytoprotection. Sorbitol dehydrogenase mRNA was detected in all tissues except small intestine, in agreement with sorbitol resorbtion by passive diffusion in this tissue. In addition, evidence for a sex-specific expression, in the liver, of class-II alcohol dehydrogenase was obtained.

The major ethanol-active form of chicken liver alcohol dehydrogenase was characterized. The primary structure was determined by peptide analysis and, to a large part, was also deduced by cDNA analysis of a near full-length cDNA clone. The latter was detected by screening of a chicken liver cDNA library with antibodies raised against the purified dehydrogenase. The structure shows that the avian enzyme exhibits characteristics of the complex mammalian alcohol dehydrogenase system, tracing its origin and divergence, and allowing functional correlations. The chicken protein analyzed proves to be a class I alcohol dehydrogenase, with 74% residue identity to gamma chains of the human enzyme, a Km for ethanol of 0.5 mM and a Ki for 4-methyl pyrazole of 2.5 microM. Relationships to the other two classes are non-identical; residue exchanges towards the human classes increase in the order I less than III less than II, and human/chicken differences are less than inter-class differences. Consequently, the origins of the classes are more distant than the avian/mammalian separation. They reflect duplicatory events separated in time, and the lines that lead to present-day classes I and II deviate early. Integrated with the data for the quail enzyme, the structure of the chicken protein shows that within the avian enzymes the degree of variation is comparable to that within the mammalian class I enzymes, which are more variable than the class III forms. The coenzyme-binding and substrate-binding residues of this chicken alcohol dehydrogenase are largely identical to those in the mammalian class I counterparts. However, the subunit-interacting areas are more variable and suggest some relationships of the avian enzyme with both class I and III mammalian forms. One of the residues, Gly260 (mammalian class I numbering system), previously considered characteristic of all alcohol dehydrogenases, is replaced by Gln.