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71.
The photodynamic response of the anthraquinone anticancer drug aclarubicin (ACL) was investigated in vitro and compared with that of mitoxantrone (MTX). Cultured immortalized rodent B14 and NIH 3T3 cells were used in the experiments as a model for cells with neoplastic phenotype. Long-term cytotoxicity and inhibition of cell proliferation assayed by the clonal growth and MTT-tetrazolium methods were estimated to compare the efficacy of aclarubicin and mitoxantrone in photosensitizing cells and their death after non-thermal exposure to monochromatic laser light. Green He-Ne (543.5 nm) or red semiconductor (670 nm) low-power laser (LPL) irradiations were applied. Different dose-responses of both cell lines to aclarubicin and mitoxantrone were found so that the cytotoxicity of MTX was considerably greater than the cytotoxicity of ACL. Phototherapy response (P < 0.0001) was observed only for B14 cells after sensitisation with aclarubicin. Under the same conditions no significant effect of red light irradiation (semiconductor 670 nm laser) on survival of both cell lines treated with mitoxantrone was found. 相似文献
72.
Tyrosine kinase inhibitors are relatively new targeted therapy drugs used for the treatment of metastatic clear cell kidney carcinoma, gastrointestinal stromal tumours, thyroid carcinoma and pancreatic neuroendocrine tumours during the progression of the disease. Hypothyroidism or thyroid dysfunction is often a side effect of this treatment. Therefore, monitoring of thyroid hormone levels before the beginning and during the treatment of tyrosine kinase inhibitors is a necessity. Hypothyroidism correlates with objective response to the treatment. Sunitinib. This is the most described tyrosine kinase inhibitor which causes hypothyroidism. The mechanism of hypothyroidism is still unclear. Sorafenib. Symptoms of hypothyroidism occur in 18% of patients treated with sorafenib due to metastatic renal cell carcinoma. Imatinib. Hypothyroidism is one of the most frequent side effects of the treatment. Emergent tracheotomy was necessary due to larynx swelling during marked hypothyroidism. Motesanib. Hypothyroidism or increased TSH level is diagnosed in 22% to 69% of patients with metastatic differentiated or medullary thyroid carcinomas. The management of patients with thyroid dysfunction and related symptoms such as fatigue is undoubtedly a challenge to an oncologist. 相似文献
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74.
Botao Zhang Chris Carrie Aneta Ivanova Reena Narsai Monika W. Murcha Owen Duncan Yan Wang Simon R. Law Verónica Albrecht Barry Pogson Estelle Giraud Olivier Van Aken James Whelan 《The Journal of biological chemistry》2012,287(50):41757-41773
The Arabidopsis thaliana genome contains two genes with homology to the mitochondrial protein LETM1 (leucine zipper-EF-hand-containing transmembrane protein). Inactivation of both genes, Atletm1 and Atletm2, together is lethal. Plants that are hemizygous for AtLETM2 and homozygous for Atletm1 (letm1(−/−) LETM2(+/−)) displayed a mild retarded growth phenotype during early seedling growth. It was shown that accumulation of mitochondrial proteins was reduced in hemizygous (letm1(−/−) LETM2(+/−)) plants. Examination of respiratory chain proteins by Western blotting, blue native PAGE, and enzymatic activity assays revealed that the steady state level of ATP synthase was reduced in abundance, whereas the steady state levels of other respiratory chain proteins remained unchanged. The absence of a functional maternal AtLETM2 allele in an Atletm1 mutant background resulted in early seed abortion. Reciprocal crosses revealed that maternally, but not paternally, derived AtLETM2 was absolutely required for seed development. This requirement for a functional maternal allele of AtLETM2 was confirmed using direct sequencing of reciprocal crosses of Col-0 and Ler accessions. Furthermore, AtLETM2 promoter β-glucuronidase constructs displayed exclusive maternal expression patterns. 相似文献
75.
Kotyńska J Petelska AD Szeremeta M Niemcunowicz-Janica A Figaszewski ZA 《The Journal of membrane biology》2012,245(4):185-190
The objective of the investigation was evaluation of postmortem changes of electric charge of human erythrocyte and thrombocyte membranes after sudden unexpected death. The surface charge density values were determined on the basis of the electrophoretic mobility measurements of the cells carried out at various pHs of electrolyte solution. The interactions between both erythrocyte and thrombocyte membranes and electrolyte ions were studied. Values of parameters characterizing the membrane--that is, the total surface concentrations of both acidic and basic groups and their association constants with solution ions--were calculated on the basis of a four-equilibria mathematical model. The model was validated by comparison of these values to experimental data. We established that examined electric properties of the cell membranes are affected by sudden unexpected death. Postmortem processes occurring in the cell membranes can lead to disorders of existing equilibria, which in turn result in changes in values of all the above-mentioned parameters. 相似文献
76.
The ultrastructure of spermiogenesis and mature spermatozoon in Lytocestus indicus (Cestoda: Lytocestidae) is described; this is the first representative of this group of monozoic, presumably most basal, tapeworms (Eucestoda) from the Indomalayan region to be documented in this manner. Similarly, as in other caryophyllideans, its spermiogenesis involves the formation of a conical differentiation zone with 2 centrioles associated with striated roots and an intercentriolar body. In the course of the process, 1 of the centrioles develops a free flagellum, which fuses with a cytoplasmic protrusion, whereas the other remains oriented in a cytoplasmic bud. Spermiogenesis is also characterized by the presence of electron-dense material in the early stages of spermiogenesis and a slight rotation of the flagellar bud. The mature spermatozoon of L. indicus is a filiform cell tapered at both extremities that lacks mitochondria; its nucleus has parallel disposition to the axoneme and does not reach up to the posterior extremity of the spermatozoon, which is typical for spermatozoa of the type III pattern. The new data confirm that caryophyllideans share the same type of spermiogenesis that is considered to be plesiomorphic in the Eucestoda. The existing information on spermatological ultrastructure of 8 members for 3 of 4 caryophyllidean families from different host groups (cyprinids and catostomids, both Cypriniformes, and mochokids and clariids, both Siluriformes) from 4 zoogeographical regions (Palearctic, Neotropic, Ethiopian, and Indomalayan regions) demonstrates great uniformity in spermiogenesis and sperm ultrastructure, which does not reflect different taxonomic position of the species studied. 相似文献
77.
Otocka-Kmiecik A Mikhailidis DP Nicholls SJ Davidson M Rysz J Banach M 《Progress in lipid research》2012,51(4):314-324
High density lipoprotein (HDL) has many properties, which contribute to its atheroprotective role. However, some recent clinical trials have identified subjects with the progression of atherosclerosis despite normal levels of HDL cholesterol. This raises the question if all subfractions of HDL have the same properties. Moreover, recent investigations have shown that both acute and chronic inflammation may lead to structural and functional changes of HDL, which render the particles proinflammatory. Although therapeutic agents that increase HDL levels are now quite well established it is not clear whether they influence HDL quality. We review the current state of knowledge on the properties of HDL and factors/therapeutic agents which may restrain the transformation of normal HDL into dysfunctional HDL. 相似文献
78.
Marzoug D Boutiba Z Gibson DI Pérez-del-Olmo A Kostadinova A 《Systematic parasitology》2012,81(3):169-186
Five species of digeneans parasitic in the pilchard Sardina pilchardus (Walbaum), a little studied host, from off the Algerian coast of the western Mediterranean are redescribed. These are Parahemiurus merus (Linton, 1910) Manter, 1940, Aphanurus stossichii (Monticelli, 1891) Looss, 1907, Aphanurus virgula Looss, 1907, Lecithaster confusus Odhner, 1905 and Pronoprymna ventricosa (Rudolphi, 1819) Poche, 1926. One of these, A. virgula, is a new record for this host. One other digenean, Hemiurus luehei Odhner, 1905, was also recorded from this host. A complete checklist of the helminth parasites of S.
pilchardus throughout its distributional range, comprising 104 host-parasite records of 39 taxa, is presented. 相似文献
79.
80.
Drzymała-Czyż S Banasiewicz T Tubacka M Tarasiuk-Rusek A Majewski P Drews M Walkowiak J 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2012,50(1):125-129
Docosahexaenoic acid (DHA) potentially modulates inflammatory processes. Therefore, the aim of this study was to determine the influence of DHA supplementation on the expression of intestinal inflammation and nutritional status in rats which have undergone restorative proctocolectomy. Twenty-four Wistar rats were operated. After the induction of pouchitis, animals were randomly divided into a control group (CG) and supplementation groups receiving respectively a semi-synthetic diet without or with DHA (in a lower or higher dose, respectively known as the lower dose, LD, and higher dose, HD, groups) for six weeks. Selected nutritional parameters were assessed. Histopathological and immunohistochemical analysis of pouch mucosa specimens was also performed. The effectiveness of feeding and quality of stools were significantly better in the HD group than in the CG. The intensity of inflammation (Moskovitz scale) was higher in HD and LD than in CG (p = 0.03 and p = 0.0006, respectively). Nevertheless, pouch adaptation (Laumonier scale) was more significant in LD than in CG (p = 0.007). On the other hand, tissue expression of IL-1α and IL-10 was higher in HD and LD than in CG (IL-1α, p = 0.009 and p = 0.05, respectively; IL-10, p = 0.04 for both). DHA supplementation has no impact on body weight gain. Yet it seems that it may improve the effectiveness of nutrition and stool quality in rats which have undergone restorative proctocolectomy. Simultaneously, it increases the intensity of pouch adaptation and inflammation. The specificity of observed changes is not clear. However, it may imply potential modulation of inflammatory processes of pouch mucosa. 相似文献