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71.
Joke A. Putseys Liesbeth J. Derde Lieve Lamberts Hans Goesaert Jan A. Delcour 《Carbohydrate polymers》2009,78(4):854-861
When amylose was synthesized using potato phosphorylase in the presence of amylose complexing lipids, monodisperse populations of amylose–lipid complexes were formed. Enzyme dosage and glucose-1-phosphate (glc-1-P)/primer ratio influenced the reaction rate of the enzymic synthesis, presumably by changing the balance between amylose synthesis and amylose–lipid complexation and precipitation, and impacted the molecular weight of the complexes. Lipid characteristics affected the dissociation properties and amylose chain lengths of the amylose–lipid complexes presumably by determining the minimal amylose chain length necessary for complexation and precipitation. Tailor made short chain amylose–lipid complexes can hence be produced by choosing the appropriate reaction conditions. We propose a synthesis mechanism in which the primer is elongated until an amylose chain is obtained which is of sufficient length to complex a first lipid. Further chain extension then occurs, together with subsequent complexation until the complex becomes insoluble and precipitates. 相似文献
72.
Vercauteren FG Flores G Ma W Chabot JG Geenen L Clerens S Fazel A Bergeron JJ Srivastava LK Arckens L Quirion R 《Proteomics》2007,7(19):3569-3579
Limited information is currently available on molecular events that underlie schizophrenia-like behaviors in animal models. Accordingly, we developed an organelle proteomic approach enabling the study of neurotransmission-related proteins in the prefrontal cortex (PFC) of postpubertal (postnatal day 60 (PD60)) neonatally ventral hippocampal (nVH) lesioned rats, an extensively used neurodevelopmental model of schizophrenia-like behaviors. The PFC was chosen because of its purported role in the etiology of the disease. Statistical analysis of 392 reproducible spots on 2-D organelle proteomic patterns revealed significant changes in intensity of 18 proteinous spots in plasma membrane-enriched fractions obtained from postpubertal nVH lesioned rats compared to controls. Mass spectrometric analysis and database searching allowed the identification of a single protein in each of the nine differential spots, including proteins of low abundance, such as neurocalcin delta. Most of the identified dysregulated proteins, including clathrin light chain B, syntaxin binding protein 1b and visinin-like protein 1 are known to be linked to various neurotransmitter systems and to play key roles in plasma membrane receptor expression and recycling as well as synaptic vesicle exocytosis/recycling. Organelle proteomic approaches have hence proved to be most useful to identify key proteins linked to a given behavior in animal models of brain diseases. 相似文献
73.
Clinckspoor I Hauben E Verlinden L Van den Bruel A Vanwalleghem L Vander Poorten V Delaere P Mathieu C Verstuyf A Decallonne B 《The journal of histochemistry and cytochemistry》2012,60(7):502-511
1,25-Dihydroxyvitamin D(3) (1,25(OH)(2)D(3)), the active form of vitamin D, mediates antitumor effects in various cancers. The expression of key players in vitamin D signaling in thyroid tumors was investigated. Vitamin D receptor (VDR) and CYP27B1 and CYP24A1 (respectively activating and catabolizing vitamin D) expression was studied (RT-PCR, immunohistochemistry) in normal thyroid, follicular adenoma (FA), differentiated thyroid cancer (DTC) consisting of the papillary (PTC) and follicular (FTC) subtype, and anaplastic thyroid cancer (ATC). VDR, CYP27B1, and CYP24A1 expression was increased in FA and DTC compared with normal thyroid. However, in PTC with lymph node metastasis, VDR and CYP24A1 were decreased compared with non-metastasized PTC. In ATC, VDR expression was often lost, whereas CYP27B1/CYP24A1 expression was comparable to DTC. Moreover, ATC with high Ki67 expression (>30%) or distant metastases at diagnosis was characterized by more negative VDR/CYP24A1/CYP27B1 staining. In conclusion, increased expression of key players involved in local 1,25(OH)(2)D(3) signaling was demonstrated in benign and differentiated malignant thyroid tumors, but a decrease was observed for local nodal and especially distant metastasis, suggesting a local antitumor response of 1,25(OH)(2)D(3) in early cancer stages. These findings advocate further studies with 1,25(OH)(2)D(3) and analogs in persistent and recurrent iodine-refractory DTC. 相似文献
74.
Torres E Duque MD López-Querol M Taylor MC Naesens L Ma C Pinto LH Sureda FX Kelly JM Vázquez S 《Bioorganic & medicinal chemistry》2012,20(2):942-948
The synthesis of several 6,7,8,9,10,11-hexahydro-9-methyl-5,7:9,11-dimethano-5H-benzocyclononen-7-amines is reported. Several of them display low micromolar NMDA receptor antagonist and/or trypanocidal activities. Two compounds are endowed with micromolar anti vesicular stomatitis virus activity, while only one compound shows micromolar anti-influenza activity. The anti-influenza activity of this compound does not seem to be mediated by blocking of the M2 protein. 相似文献
75.
Van Zeghbroeck L 《Gerodontology》2012,29(2):e1176-e1179
doi: 10.1111/j.1741‐2358.2011.00521.x CAD/CAM treatment for the elderly – a case report Background: When elderly develop signs and symptoms of Alzheimer’s disease they lose their independence and neglect dental hygiene. Dentists are increasingly confronted by seniors who are in need but who have limited access to dental care. Caretakers and family are also often confronted with behaviour problems besides the dental problems. Objective: To report the importance of shorter and lower impact treatment for seniors when caretakers and family are confronted with a behavioural problem in addition to the dental problem. Materials and methods: In this case report, the oral management of a patient with Alzheimer’s disease was described using chairside computer‐aided design/computer‐aided manufacturing (CAD/CAM) technology while constructing a bonded bridge. Discussion: The case report emphasises the importance of interaction with the patient and added a treatment method for patients with limited cognitive skills who become easily agitated or aggressive. Conclusion: The fabrication of a full ceramic bonded bridge utilising the Cerec 3D chairside CAD/CAM technology in an Alzheimer patient has been shown to be a feasible, precise, aesthetic and durable solution. It added a technique for intervening with patients with limited tolerance for dental procedures, which improves the quality of life of both patient and family. 相似文献
76.
Real-time polymerase chain reaction melting curve analysis (MCA) allows differentiation of several free-living amoebae species.
Distinctive characteristics were found for Naegleria fowleri, N. lovaniensis, N. australiensis, N. gruberi, Hartmanella vermiformis, and Willaertia magna. Species specificity of the amplicons was confirmed using agarose gel electrophoresis and sequence-based approaches. Amplification
efficiency ranged from 91% to 98%, indicating the quantitative potential of the assay. This MCA approach can be used for quantitative
detection of free-living amoebae after cultivation but also as a culture-independent detection method. 相似文献
77.
Vitamin D and cancer 总被引:1,自引:0,他引:1
78.
Grigoris Zoidis Nicolas Kolocouris Lieve Naesens Erik De Clercq 《Bioorganic & medicinal chemistry》2009,17(4):1534-1541
1–2 Annulated adamantane piperidines 4, 6, 16, 17, 19, 23 and 25 were synthesized and evaluated for anti-influenza A virus activity. The stereoelectronic requirements for optimal antiviral potency were investigated. Piperidine 23 proved to be the most active of the compounds tested against influenza A virus, being 3.5-fold more active than amantadine, equipotent to rimantadine and 15-fold more potent than ribavirin. It is noteworthy that piperidine 23 displayed one of the highest selectivity indexes (SI > 732) among aminoadamantanes or other cage structure amines tested till now. 相似文献
79.
80.
Sophie Marchand Kim Heylen Winy Messens Katleen Coudijzer Paul De Vos Koen Dewettinck Lieve Herman Jan De Block Marc Heyndrickx 《Environmental microbiology》2009,11(2):467-482
Psychrotolerant bacteria and their heat-resistant proteases play a major role in the spoilage of UHT-processed dairy products. Summer and winter raw milk samples were screened for the presence of such bacteria. One hundred and three proteolytic psychrotolerant bacteria were isolated, characterized by API tests, rep-PCR fingerprint analysis and evaluated for heat-resistant protease production. Twenty-nine strains (representing 79% of the complete collection) were further identified by 16S rRNA gene sequencing, rpoB gene sequencing and DNA–DNA hybridizations. A seasonal inter- and intra-species influence on milk spoilage capacity (e.g. growth rate and/or protease production) was demonstrated. Moreover, this polyphasic approach led to the identification of Pseudomonas fragi and Pseudomonas lundensis (representing 53% of all isolates) as predominant producers of heat-resistant proteases in raw milk. The role of Pseudomonas fluorescens , historically reported as important milk spoiler, could not unequivocally be established. The use of more reliable identification techniques and further revision of the taxonomy of P. fluorescens will probably result in a different perspective on its role in the milk spoilage issue. 相似文献