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261.
Probiotic utilization is becoming increasingly popular in veterinary medicine. However, only few probiotic products are available commercially for use in dogs in our market. Therefore, the aim of our study was to determine the properties of new potential probiotic Lactobacillus fermentum AD1 strain-own canine isolate and to investigate its effect on several microbiological and biochemical parameters in healthy dogs. The strain expressed in vitro survival by pH 3.0 after 3h (86.8%) and in the presence of 1% bile (75.4%). The AD1 strain adhered to the canine and human intestinal mucus. It was sensitive to commonly used antimicrobials. Fifteen healthy dogs were supplemented with 10(9)L. fermentum AD1 for 7 days. At the end of AD1 strain application, numbers of faecal lactobacilli and enterococci increased significantly in the canine faeces. Significant increase of total protein and total lipid and significant reduction of glucose in serum of dogs were noted. These data indicate that L. fermentum AD1 survive transit through the canine gastrointestinal tract, and populate the colon and probably increased absorption of some nutrients. Whether longer time of its application lead to the same results as well as its potential to improve immune function in dogs remains to be determined. 相似文献
262.
The freshwater filamentous green oxyphotobacterium Prochlorothrix hollandica is an unusual oxygenic photoautotrophic cyanobacterium differing from most of the others by the presence of light-harvesting Pcb antenna binding both chlorophylls a and b and by the absence of phycobilins. The pigment-protein complexes of P. hollandica SAG 10.89 (CCAP 1490/1) were isolated from dodecylmaltoside solubilized thylakoid membranes on sucrose density gradient and characterized by biochemical, spectroscopic and immunoblotting methods. The Pcb antennae production is suppressed by high light conditions (> 200 μmol photons m−2 s−1) in P. hollandica. PcbC protein was found either in higher oligomeric states or coupled to PS I (forming antenna rings around PS I). PcbA and PcbB are most probably only very loosely bound to photosystems; we assume that these pigment-protein complexes function as low light-induced mobile antennae. Further, we have detected α-carotene in substantial quantities in P. hollandica thylakoid membranes, indicating the presence of chloroplast-like carotenoid synthetic pathway which is not present in common cyanobacteria. 相似文献
263.
Miroslava Barančeková Jarmila Krojerová-Prokešová Pavel Šustr Marco Heurich 《European Journal of Wildlife Research》2010,56(3):327-333
The composition of roe deer diet in the Bohemian Forest was analysed with the aim to assess its role in forest habitat altered by bark beetle outbreaks and wind calamities. The annual diet of roe deer was studied at both, Czech and German, sides of the Bohemian Forest using microscopic analyses of faeces. On average, the largest part of the roe deer diet consisted of forbs (32%), followed by three other components—grasses (17%), coniferous trees (13%) and broadleaved trees (11%). Overall the results show that the composition of roe deer diet in the Bohemian Forest is that of a typical concentrate selector. 相似文献
264.
In the heart, the proteomes secreted by both cardiac stem cells (CSCs) and cardiac myocytes could act synergistically, but the identification and functionality of the proteins comprising the individual secretomes have not yet been described. In this study, we have identified proteins present in the media obtained from cultured rat CSCs and from cultured neonatal rat ventricular myocytes (NRVMs) and compared them with proteins identified in the media alone. Briefly, 83 unique proteins were identified after analysis by RPLC and MS. In total 49 and 23% were NRVM‐specific or CSC‐specific proteins, respectively, and 63% of total 83 proteins were integral plasma membrane and/or known secreted proteins. Fifteen proteins met our criteria for paracrine/autocrine factors: (i) robust protein identification, (ii) cell specific and (iii) known to be secreted. Most of these proteins have not been previously linked to stem cells. NRVM‐specific proteins atrial natriuretic factor (ANP) and connective tissue growth factor, and CSC‐specific protein interleukin‐1 receptor‐like 1 (ST2) were found to affect rat CSC proliferation. These findings suggest that relative concentration of each protein may be crucial for cellular intertalk and for the final outcome of cardiac cell therapy. 相似文献
265.
Svetlana B Savin Dubravka S Cveji? Miroslava M Jankovi? 《The journal of histochemistry and cytochemistry》2003,51(4):479-483
High levels of expression of galectin-1 and galectin-3, the beta-galactoside-binding proteins, have been recently described in malignant thyroid tumors but not in adenomas nor in normal thyroid tissue. However, there are no data about the expression of these galectins during fetal thyroid development. In this study we analyzed immunohistochemically the presence of galectin-1 and galectin-3 in human fetal thyroid glands (16-37 weeks of gestation). Weak to moderate cytoplasmic staining for galectin-1 was observed in follicular cells of all fetal thyroids. Galectin-3 could not be detected in thyroid follicular cells of any fetal thyroid investigated. Both galectins were detected in stromal tissue, but staining for galectin-1 was more intense. The absence of galectin-3 in thyroid cells during fetal development suggests that galectin-3 is expressed de novo during malignant transformation of thyroid epithelium, and that galectin-1 could be considered an oncofetal antigen. The results obtained indicated potential roles for galectin-1 and galectin-3 during the investigated period of human fetal thyroid gland development. Both galectins might participate in developmental processes regarding stromal fetal thyroid tissue organization, whereas galectin-1 might have a function in thyroid epithelium maturation. 相似文献
266.
Kucerova L Matuskova M Pastorakova A Tyciakova S Jakubikova J Bohovic R Altanerova V Altaner C 《The journal of gene medicine》2008,10(10):1071-1082
Background
Previously, we validated capability of human adipose tissue‐derived mesenchymal stem cells (AT‐MSC) to serve as cellular vehicles for gene‐directed enzyme prodrug molecular chemotherapy. Yeast fusion cytosine deaminase : uracil phosphoribosyltransferase expressing AT‐MSC (CDy‐AT‐MSC) combined with systemic 5‐fluorocytosine (5FC) significantly inhibited growth of human colon cancer xenografts. We aimed to determine the cytotoxic efficiency to other tumour cells both in vitro and in vivo.Methods
CDy‐AT‐MSC/5FC‐mediated proliferation inhibition against a panel of human tumour cells lines was evaluated in direct and indirect cocultures in vitro. Antitumour effect was tested on immunodeficient mouse model in vivo.Results
Although culture expansion of CDy‐AT‐MSC sensitized these cells to 5FC mediated suicide effect, expanded CDy‐AT‐MSC/5FC still exhibited strong bystander cytotoxic effect towards human melanoma, glioblastoma, colon, breast and bladder carcinoma in vitro. Most efficient inhibition (91%) was observed in melanoma A375 cell line when directly cocultured with 2% of therapeutic cells CDy‐AT‐MSC/5FC. The therapeutic paradigm of the CDy‐AT‐MSC/5FC system was further evaluated on melanoma A375 xenografts on nude mice in vivo. Complete regression in 89% of tumours was achieved when 20% CDy‐AT‐MSC/5FC were co‐injected along with tumour cells. More importantly, systemic CDy‐AT‐MSC administration resulted in therapeutic cell homing into subcutaneous melanoma and mediated tumour growth inhibition.Conclusions
CDy‐AT‐MSC capability of targeting subcutaneous melanoma offers a possibility to selectively produce cytotoxic agent in situ. Our data further demonstrate beneficial biological properties of AT‐MSC as a cellular vehicle for enzyme/prodrug therapy approach to molecular chemotherapy. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献267.
Correlation between genetic and geographic structure in Europe 总被引:7,自引:0,他引:7
Lao O Lu TT Nothnagel M Junge O Freitag-Wolf S Caliebe A Balascakova M Bertranpetit J Bindoff LA Comas D Holmlund G Kouvatsi A Macek M Mollet I Parson W Palo J Ploski R Sajantila A Tagliabracci A Gether U Werge T Rivadeneira F Hofman A Uitterlinden AG Gieger C Wichmann HE Rüther A Schreiber S Becker C Nürnberg P Nelson MR Krawczak M Kayser M 《Current biology : CB》2008,18(16):1241-1248
Understanding the genetic structure of the European population is important, not only from a historical perspective, but also for the appropriate design and interpretation of genetic epidemiological studies. Previous population genetic analyses with autosomal markers in Europe either had a wide geographic but narrow genomic coverage [1] and [2], or vice versa [3], [4], [5] and [6]. We therefore investigated Affymetrix GeneChip 500K genotype data from 2,514 individuals belonging to 23 different subpopulations, widely spread over Europe. Although we found only a low level of genetic differentiation between subpopulations, the existing differences were characterized by a strong continent-wide correlation between geographic and genetic distance. Furthermore, mean heterozygosity was larger, and mean linkage disequilibrium smaller, in southern as compared to northern Europe. Both parameters clearly showed a clinal distribution that provided evidence for a spatial continuity of genetic diversity in Europe. Our comprehensive genetic data are thus compatible with expectations based upon European population history, including the hypotheses of a south-north expansion and/or a larger effective population size in southern than in northern Europe. By including the widely used CEPH from Utah (CEU) samples into our analysis, we could show that these individuals represent northern and western Europeans reasonably well, thereby confirming their assumed regional ancestry. 相似文献
268.
Miroslava Kameníková Paul Georg Furtmüller Mária Klacsová Arturo Lopez‐Guzman José Luis Toca‐Herrera Anika Vitkovská Ferdinand Devínsky Pavel Mučaji Milan Nagy 《Luminescence》2017,32(7):1203-1211
Protein‐binding interactions are displacement reactions which have been implicated as the causative mechanisms in many drug–drug interactions. Thus, the aim of presented study was to analyse human serum albumin‐binding displacement interaction between two ligands, hypoglycaemic drug gliclazide and widely distributed plant flavonoid quercetin. Fluorescence analysis was used in order to investigate the effect of substances on intrinsic fluorescence of human serum albumin (HSA) and to define binding and quenching properties of ligand–albumin complexes in binary and ternary systems, respectively. Both ligands showed the ability to bind to HSA, although to a different extent. The displacement effect of one ligand from HSA by the other one has been described on the basis of the quenching curves and binding constants comparison for the binary and ternary systems. According to the fluorescence data analysis, gliclazide presents a substance with a lower binding capacity towards HSA compared with quercetin. Results also showed that the presence of quercetin hindered the interaction between HSA and gliclazide, as the binding constant for gliclazide in the ternary system was remarkably lower compared with the binary system. This finding indicates a possibility for an increase in the non‐bound fraction of gliclazide which can lead to its more significant hypoglycaemic effect. Additionally, secondary and tertiary structure conformational alterations of HSA upon binding of both ligands were investigated using synchronous fluorescence, circular dichroism and FT‐IR. Experimental data were complemented with molecular docking studies. Obtained results provide beneficial information about possible interference upon simultaneous co‐administration of the food/dietary supplement and drug. 相似文献
269.
Kosnar J Kosnar J Herbstová M Macek P Rejmánková E Stech M 《American journal of botany》2010,97(7):1229-1240
? Premise of the study: Natural hybridization represents an important force driving plant evolution and affecting community structure and functioning. Hybridization may be overlooked, however, among morphologically highly uniform congeners. An excellent example of such a group is Eleocharis subgenus Limnochloa, which has no reliably proven hybrids. Does this reflect biological barriers to interspecific crosses or difficulties in detecting the hybrids? We tested the hypothesis that hybridization occurs among sympatric Eleocharis cellulosa, E. interstincta, and E. mutata in northern Belize, Central America. ? Methods: Morphometric study (407 plants) was followed by examination of inter-simple sequence repeat (ISSR) polymorphisms (44 plants) and ITS sequence variation (33 plants). ? Key results: Two putatively hybrid morphotypes were discerned-E. cellulosa-resembling and E. interstincta-resembling. DNA markers of E. cellulosa and E. interstincta displayed additive constitution in plants from one E. cellulosa-resembling population only. The other putatively hybrid populations contained ISSR and ITS markers of the species they resembled morphologically, several unique ISSR markers, and ITS sequences of an undescribed South American Limnochloa entity. DNA markers of E. mutata were absent in the putative hybrids. ? Conclusions: Simultaneous use of various types of molecular markers can overcome many pitfalls of investigations concerning hybridization among closely related and morphologically similar species. Northern Belize represents a hybrid zone of E. cellulosa and E. interstincta. A third participant in the hybridization events occurring in this zone is an unknown Limnochloa lineage but is not E. mutata. Interspecific hybridization may play a significant role in the diversification of Eleocharis. 相似文献
270.
Tulinska J Jahnova E Dusinska M Kuricova M Liskova A Ilavska S Horvathova M Wsolova L Kyrtopoulos SA Collins A Harrington V Fuortes L 《Mutation research》2004,553(1-2):111-124
In the context of a large-scale molecular epidemiology study, the possible immunomodulatory effects of mineral fibres, in workers occupationally exposed to asbestos, rockwool and glass fibres, were examined. In each plant, 61, 98 and 80 exposed workers and 21, 43 or 36 control clerical subjects, respectively, were recruited. In the case of the asbestos-exposed subjects, an additional town-control group of 49 people was included. Evidence of pulmonary fibrosis was found in 42% of the asbestos-exposed workers, while evidence of pleural fibrosis was found in 24%. The asbestos-exposed cohort had significantly decreased forced vital capacity of lungs as well as forced expiratory volume per first second. Our findings indicate that exposure to all three types of fibres examined modulates to different degrees the immune response. Suppression of T-cell immunity and to a lesser extent, B-cell immunity was found in the case of workers from a former asbestos cement plant, while stimulation of T-cell response was observed in rockwool workers, and stimulation of T- and B-cell response was seen in glass fibre workers. Depression of the percentage of lymphocyte subpopulation of CD 16+56 (natural killer cells) in peripheral blood was found in glass fibre workers. Statistical analysis showed increased levels of proinflammatory cytokines (IL-6 asbestos; IL-8 all three fibres), expression of adhesion molecule L-selectin on granulocytes and monocytes (asbestos), levels of soluble adhesion molecules (SAMs) in sera (ICAM-1 all three fibres; E-selectin glass fibres), increased levels of immunoglobulin E (asbestos and rockwool) and elevated expression of activation markers on eosinophils (CD66b asbestos, glass fibres; CD69 asbestos). Significant correlations were observed between lymphocyte proliferation and markers of DNA damage and repair. Increased levels of proinflammatory cytokines, SAMs, immunoglobulin E and elevated expression of activation markers on eosinophils was found in people with symptoms of hypersensitivity and an elevated inflammatory status. 相似文献