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991.
Josef Kovarik Charles Kelly Nick West Michael Drinnan Werner Dobrowsky Muhammad Shahid Iqbal 《Reports of Practical Oncology and Radiotherapy》2022,27(3):577
BackgroundThe purpose of this study was to assess the impact of coincidental radiotherapy on the volume of the non-malignant prostate gland in rectal cancer patients treated with neo-adjuvant radiotherapy.Materials and methodsIn this retrospective analysis, thirty male patients with rectal cancer who had neoadjuvant radiotherapy met the inclusion criteria. These patients had pre-treatment magnetic resonance imaging (MRI) and at least one post-treatment MRI of the pelvis and the whole of their prostate volume received the full prescribed radiotherapy dose; 45 Gy in 25 fractions (n = 22), 45 Gy in 20 fractions (n = 4) and 25 Gy in 5 fractions (n = 4).ResultsThe median age of this patient cohort was 66 years (range: 30–87). With a median interval between pre-treatment MRI and first MRI post-treatment of 2 months (range: 1–11), the mean prostate volume reduced from 36.1 cm3 [standard deviation (SD) 14.2] pre-radiotherapy to 31.3 cm3 (SD 13.0) post radiotherapy and this difference was significant (p = 0.0004).ConclusionRadiotherapy may cause shrinkage in volume of normal (non-malignant) prostate. Further research is required in this field, since these results may be of some comfort to men contemplating the consequences of radiotherapy on their quality of life. The authors suggest recording flow-rate and international prostate symptom score (IPSS) during rectal radiotherapy as a next step. 相似文献
992.
Miruna Carmen Barbu Mat Harris Xueyi Shen Stolicyn Aleks Claire Green Carmen Amador Rosie Walker Stewart Morris Mark Adams Anca Sandu Christopher McNeil Gordon Waiter Kathryn Evans Archie Campbell Joanna Wardlaw Douglas Steele Alison Murray David Porteous Andrew McIntosh Heather Whalley 《Epigenetics》2022,17(10):1143
993.
Francisco InestaVaquera Florian Weiland Colin J. Henderson Charles Roland Wolf 《Journal of cellular and molecular medicine》2022,26(21):5463
Age‐related diseases account for a high proportion of the total global burden of disease. Despite recent advances in understanding their molecular basis, there is a lack of suitable early biomarkers to test selected compounds and accelerate their translation to clinical trials. We have investigated the utility of in vivo stress reporter systems as surrogate early biomarkers of the degenerative disease progression. We hypothesized that cellular stress observed in models of human degenerative disease preceded overt cellular damage and at the same time will identify potential cytoprotective pathways. To test this hypothesis, we generated novel accelerated ageing (progeria) reporter mice by crossing the LmnaG609G mice into our oxidative stress/inflammation (Hmox1) and DNA damage (p21) stress reporter models. Histological analysis of reporter expression demonstrated a time‐dependent and tissue‐specific activation of the reporters in tissues directly associated with Progeria, including smooth muscle cells, the vasculature and gastrointestinal tract. Importantly, reporter expression was detected prior to any perceptible deleterious phenotype. Reporter expression can therefore be used as an early marker of progeria pathogenesis and to test therapeutic interventions. This work also demonstrates the potential to use stress reporter approaches to study and find new treatments for other degenerative diseases. 相似文献
994.
Roger S. McIntyre Martin Alda Ross J. Baldessarini Michael Bauer Michael Berk Christoph U. Correll Andrea Fagiolini Kostas Fountoulakis Mark A. Frye Heinz Grunze Lars V. Kessing David J. Miklowitz Gordon Parker Robert M. Post Alan C. Swann Trisha Suppes Eduard Vieta Allan Young Mario Maj 《World psychiatry》2022,21(3):364
Bipolar disorder is heterogeneous in phenomenology, illness trajectory, and response to treatment. Despite evidence for the efficacy of multimodality interventions, the majority of persons affected by this disorder do not achieve and sustain full syndromal recovery. It is eagerly anticipated that combining datasets across various information sources (e.g., hierarchical “multi‐omic” measures, electronic health records), analyzed using advanced computational methods (e.g., machine learning), will inform future diagnosis and treatment selection. In the interim, identifying clinically meaningful subgroups of persons with the disorder having differential response to specific treatments at point‐of‐care is an empirical priority. This paper endeavours to synthesize salient domains in the clinical characterization of the adult patient with bipolar disorder, with the overarching aim to improve health outcomes by informing patient management and treatment considerations. Extant data indicate that characterizing select domains in bipolar disorder provides actionable information and guides shared decision making. For example, it is robustly established that the presence of mixed features – especially during depressive episodes – and of physical and psychiatric comorbidities informs illness trajectory, response to treatment, and suicide risk. In addition, early environmental exposures (e.g., sexual and physical abuse, emotional neglect) are highly associated with more complicated illness presentations, inviting the need for developmentally‐oriented and integrated treatment approaches. There have been significant advances in validating subtypes of bipolar disorder (e.g., bipolar I vs. II disorder), particularly in regard to pharmacological interventions. As with other severe mental disorders, social functioning, interpersonal/family relationships and internalized stigma are domains highly relevant to relapse risk, health outcomes, and quality of life. The elevated standardized mortality ratio for completed suicide and suicidal behaviour in bipolar disorder invites the need for characterization of this domain in all patients. The framework of this paper is to describe all the above salient domains, providing a synthesis of extant literature and recommendations for decision support tools and clinical metrics that can be implemented at point‐of‐care. 相似文献
995.
996.
Rabbit chondrocytes maintained in serum-free medium : I. Synthesis and secretion of hydrodynamically-small proteoglycans 总被引:2,自引:0,他引:2
The biosynthesis of sulfated proteoglycan in vitro by rabbit articular chondrocytes in first passage monolayer culture maintained in fetal bovine serum (FBS) or in serum-free conditions was compared. Neosynthesized proteoglycan in the culture medium in the most dense fraction of an associative CsCl density gradient (fraction dAl) declined with increasing time under serum-free conditions, but not when cells were maintained in the presence of serum. After one day, the major peak of incorporated 35SO4 in medium fraction dAl eluted as a retarded peak (Kav 0.28) on Sepharose CL-2B, whether cells were maintained under serum-free or serum-containing conditions. The hydrodynamic size of proteoglycan monomer fraction dAlDl obtained after one day of exposure to serum-free culture media was smaller than dAlDl from serum-containing cultures. The hydrodynamic size of dAlDl obtained from serum-free culture media became even progressively smaller after 2 and 3 days' exposure to these conditions. Hydrodynamically small sulfated proteoglycans were identified in the cell-associated dAlDl fraction as early as one day after switching chondrocytes from serum-containing to serum-free medium. Culture medium fraction dAlDl from serum-free culture medium aggregated poorly when incubated with human hyaluronic acid (HA) in the presence of bovine link protein or when dialysed against bovine nasal cartilage proteoglycan aggregate. Proteoglycan monomer from serum-containing medium reaggregated more efficiently under both conditions. No change in the size of glycosaminoglycan chains was seen in the smaller proteoglycan subpopulations, nor was there any indication of marked changes in the glycosaminoglycan types. 相似文献
997.
Cornelia Mauch Monique Aumailley Marc Paye Charles M. Lapire Rupert Timpl Thomas Krieg 《Experimental cell research》1986,163(2):294-300
Attachment of fibroblasts from dermatosparactic sheep and cattle to collagenous substrates (types I and IV) is defective (30-50%) when compared with fibroblasts from normal or heterozygous animals. The difference was independent of the amount of substrate, incubation time and protein synthesis. No differences were observed in the binding to fibronectin or laminin. Reduced attachment to collagen can be partially restored by adding fibronectin. The polygonal morphology of dermatosparactic cells was, however, not altered by attachment and growth on dishes coated with different collagens or fibronectin. Reduced interaction with collagens could be due to changes in specific receptors and may represent a further pathological change in dermatosparactic animals. 相似文献
998.
Sedimentation equilibrium studies are used to establish that a new pattern for the self-association of zinc-free insulin in solution is applicable over a wide range of conditions of pH, ionic strength and temperature. In this pattern, which is based on information from the existing literature on the X-ray crystal structure of insulin, the insulin monomer is viewed as having two distinct faces both capable of self-interaction. Sedimentation equilibrium experiments were analysed using expressions formulated for this association pattern that describe the dependence of weight average molecular weight and monomer concentration on total protein concentration. It has thereby been possible to obtain values for the two association constants which govern the system for each set of conditions studied, due allowance having been made for composition dependent non-ideality effects. Furthermore, by relating the pH, temperature and ionic strength dependence of the association constants with properties of various amino acid residues on the surface of the insulin monomer, it has also been possible to assign tentatively each constant to a particular reaction domain. 相似文献
999.
Richard L. Lindroth M.T.Stephen Hsia J.Mark Scriber 《Biochemical Systematics and Ecology》1987,15(6):677-680
A crude extract quaking aspen Populus tremuloides exhibits differential bioactivity against subspecies of the eastern tiger swallowtail Papilio glaucus. Components were isolated and identified on the basis of NMR and IR spectra, and chemical methods, as the phenolic glycosides salicin, salicortin, tremuloidin, and tremulacin. 相似文献
1000.
In rat pancreatic islets the effects of cholecystokinin-8 (CCK8) on glucose-mediated insulin release, 45Ca2+ net uptake, 45Ca2+ efflux, 86Rb+ efflux, cAMP- and cGMP levels were studied. In the presence of a substimulatory glucose concentration (3 mM) CCK8 concentrations of up to 1 microM had no effect on insulin release, but CCK8 at 10 nM potentiated the stimulatory effect of glucose (11.1 mM). 10 nM CCK8 enhanced glucose-stimulated 45Ca2+ net uptake but was ineffective at substimulatory glucose levels. CCK8 had no effect on cAMP and cGMP levels in the presence of 11.1 mM glucose, CCK8 increased 86Rb+ (a measure of K+) in the presence of both 3 and 11.1 mM glucose. This effect was abolished when Ca2+ was omitted from the perifusion medium. CCK8 did not alter glucose (11.1 mM)-stimulated 45Ca2+ efflux rate. These data indicate that (1) CCK8 potentiates glucose-stimulated insulin secretion possibly via an effect on Ca2+ uptake, 2) by affecting Ca2+ uptake, CCK8 enhances K+ efflux, and 3) CCK8 does not mediate its effect via cAMP or cGMP. With respect to 86Rb+ efflux the mechanism of CCK8 action appears to be different from that of glucose. When the mechanism of CCK action on islets is compared with that on exocrine pancreas (data from others) there are similarities (importance of Ca2+ uptake and non-importance of cAMP and cGMP). 相似文献