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941.
One to four different lots of four commercially available trivalent measles-mumps-rubella vaccines were tested for their efficacy as measured by the induction of antibodies to the three vaccine viruses. All of the products were satisfactory although a 100% seroconversion rate was attained regularly only with rubella vaccine. The live virus in the different measles and mumps vaccine components and especially the relative amounts of measles to mumps virus varied widely. Obviously, the efficacy of a vaccine should not be judged only by the virus content. Of main importance is the further adjustment of the dosage of the interfering vaccine virus strains in relation to their attenuation. 相似文献
942.
943.
Sven Krügener Carmen SchaperUlrich Krings Ralf G. Berger 《Bioresource technology》2009,100(11):2855-2860
Enzymatic synthesis of furanoterpenoids from β-myrcene and related monoterpenes was observed using a solubilised enzyme fraction of mycelium lyophilisates of several Pleurotus species. The initial enzymatic step, the incorporation of molecular oxygen into the conjugated 1,3-diene moiety, was similar to a 2 + 4 cycloaddition of 1,3-dienes with dienophilic 1O2, and was followed by a non-catalysed degradation sequence leading to the furans. The cyclic peroxides 3,6-dihydro-4-(2-(3,3-dimethyloxiran-2-yl)ethyl)-1,2-dioxine and 5-(3,6-dihydro-1,2-dioxin-4-yl)-2-methylpentan-2-ol were identified as key intermediates. Biotransformation of β-myrcene in 18O-labelled HEPES-buffer did not yield a detectable label in perillene, so a water addition to 3,10-epoxy-β-myrcenes as an alternative was ruled out. The pathway suggested presents a substantiated biogenetic scheme for the formation of monoterpenoid furans and opens biotechnological access to valuable natural flavour compounds, such as perillene and rosefurane. Only one metabolite, identified as the new natural compound 6-methyl-2-methylene-hept-5-enal, carried the 18O-label. The enzymatic formation of this compound through a 1,2-endoperoxide (3-(5-methyl-1-methylene-hex-4-enyl)-[1,2]-dioxetane) is suggested. The label may simply result from a chemical oxygen exchange between the carbonyl group and the 18O-labelled water. 相似文献
944.
Kristen A Mehl J Mark Davis Julie M Clements Franklin G Berger Maria M Pena James A Carson 《Journal of applied physiology》2005,98(6):2219-2225
Moderate-intensity treadmill running can alter male Apc(Min/+) mouse polyp formation. This purpose of this study was to examine whether exercise mode differentially affects Apc(Min/+) mouse intestinal polyp development in male and female mice. Male and female Apc(Min/+) mice were randomly assigned to control, treadmill (18 m/min; 60 min/day; 6 days/wk), or voluntary wheel running (24-h access) groups. Nine weeks of training decreased total intestinal polyps by 29% in male treadmill runners (66 +/- 9; P = 0.038) compared with male controls (93 +/- 7). The number of large polyps (>/=1-mm diameter) were also reduced by 38% in male treadmill runners (49 +/- 6; P = 0.005) compared with male controls (79 +/- 6). Treadmill running in female Apc(Min/+) mice and wheel running in both genders did not affect polyp number or size. Spleen weight decreased in male treadmill runners (91 +/- 9 mg; P = 0.011) and wheel runners (75 +/- 6 mg; P = 0.004) compared with controls (141 +/- 13 mg). Plasma IL-6 was reduced by 96% in male treadmill runners (1.2 +/- 0.6 pg/ml) and 78% in male wheel runners (6.6 +/- 3.3 pg/ml) compared with control mice (27.9 +/- 2.8 pg/ml; P < 0.05). Female mice responded similarly with an 86% decrease in plasma IL-6 with treadmill running (3.2 +/- 1.2 pg/ml) and 90% decrease with wheel running (2.9 +/- 2.0 pg/ml) compared with control mice (21.1 +/- 5.3 pg/ml; P < 0.05). The crypt depth-to-villus height ratio in the intestine, an indirect marker of intestinal inflammation, decreased by 21 (P = 0.024) and 24% (P = 0.029), respectively, in male and female treadmill runners but not wheel runners. Physical activity-induced attenuation of intestinal polyp number and size is dependent on exercise mode and differs between genders. The modulation of systemic and intestinal inflammation may also depend on exercise mode. 相似文献
945.
946.
The secretome of Pleurotus sapidus 总被引:1,自引:0,他引:1
Due to their unique capability to attack lignified biopolymers, extracellular enzymes of white-rot fungi enjoy an increasing interest in various fields of white biotechnology. The edible fungus Pleurotus sapidus was selected as a model organism for the analysis of the secretome by means of 2-DE. For enzyme production, the fungus was grown in submerged cultures either on peanut shells or on glass wool as a carrier material. Identification of the secreted enzymes was performed by tryptic digestion, ESI-MS/MS ab initio sequencing, and homology searches against public databases. The spectrum of secreted enzymes comprised various types of hydrolases and lignolytic enzymes of the manganese peroxidase/versatile peroxidase family. While peptidases were secreted mainly by the cultures grown on peanut shells, versatile peroxidase type enzymes dominated in the cultures grown on glass wool. 相似文献
947.
Functional analysis of tumor-specific Th cell responses detected in melanoma patients after dendritic cell-based immunotherapy 总被引:11,自引:0,他引:11
Schultz ES Schuler-Thurner B Stroobant V Jenne L Berger TG Thielemanns K van der Bruggen P Schuler G 《Journal of immunology (Baltimore, Md. : 1950)》2004,172(2):1304-1310
Recently, we have demonstrated that tumor-specific CD4+ Th cell responses can be rapidly induced in advanced melanoma patients by vaccination with peptide-loaded monocyte-derived dendritic cells. Most patients showed a T cell reactivity against a melanoma Ag 3 (MAGE-3) peptide (MAGE-3(243-258)), which has been previously found to be presented by HLA-DP4 molecules. To analyze the functional and specificity profile of this in vivo T cell response in detail, peptide-specific CD4+ T cell clones were established from postvaccination blood samples of two HLA-DP4 patients. These T cell clones recognized not only peptide-loaded stimulator cells but also dendritic cells loaded with a recombinant MAGE-3 protein, demonstrating that these T cells were directed against a naturally processed MAGE-3 epitope. The isolated CD4+ Th cells showed a typical Th1 cytokine profile upon stimulation. From the first patient several CD4+ T cell clones recognizing the antigenic peptide used for vaccination in the context of HLA-DP4 were obtained, whereas we have isolated from the second patient CD4+ T cell clones which were restricted by HLA-DQB1*0604. Analyzing a panel of truncated peptides revealed that the CD4+ T cell clones recognized different core epitopes within the original peptide used for vaccination. Importantly, a DP4-restricted T cell clone was stimulated by dendritic cells loaded with apoptotic or necrotic tumor cells and even directly recognized HLA class II- and MAGE-3-expressing tumor cells. Moreover, these T cells exhibited cytolytic activity involving Fas-Fas ligand interactions. These findings support that vaccination-induced CD4+ Th cells might play an important functional role in antitumor immunity. 相似文献
948.
Twinning in dairy cattle has been associated with many negative health and reproductive events that cause economic loss to the producer. Reports have suggested that twinning rates are increasing and that there may be a positive relationship between milk production and twinning frequency. Putative quantitative trait loci (QTL) for twinning and ovulation rate on bovine chromosomes 5, 7, 19 and 23 have been previously identified in other populations. The objective of this study was to detect and possibly confirm the existence and effects of these QTL in the North American Holstein population. Half-sib families of 20 North American Holstein sires with above average twinning rate predicted transmitting abilities (PTA) comprised the sample population under investigation. Twinning rate PTA values had been estimated from calving data. DNA extracted from semen samples was analysed using 45-61 microsatellite markers across the four chromosomes. Marker heterozygosity of the patriarchs averaged 62%. Evidence of twinning QTL was found in multiple families on chromosomes 5, 7 and 23 and in one family on chromosome 19. Four of the sires formed one three-generation family: one sire and three half-sib sons with sons of their own. This extended family was analysed with additional markers confirming a twinning QTL of significant size on chromosome 5. 相似文献
949.
950.
Gotshalk LA Berger RA Kraemer WJ 《Journal of strength and conditioning research / National Strength & Conditioning Association》2004,18(4):760-764
The purpose of this investigation was to determine the level of cardiovascular stress elicited by continuous and prolonged circuit resistance training (CRT). Each of the 11 men who volunteered as a subject were tested to determine oxygen consumption and heart rate responses to a submaximal and maximal treadmill protocol and a CRT session consisting of 10 exercises and 10 repetitions at 40% of 1 repetition maximum (1RM) for each station with 4.6 circuits performed. The physiological stress of the CRT in this study was evident by the sustained heart rate of more than 70% of maximum for 16.6 minutes, with the last 12 minutes at more than 80%. Despite the large anaerobic component in CRT, Vo(2) was sustained at 50% or more of maximum for the final 12 minutes. Treadmill running, involving large muscle groups, increased Vo(2) more rapidly than CRT, where alternating larger and smaller muscle groups were used. In addition, at the same Vo(2) heart rate differed significantly between the 2 modes of activity. Heart rate in CRT was higher (at 165) than the heart rate of 150 found during treadmill running at the same 50% Vo(2). Such workouts may be used in a training cycle in classical linear periodization or in a nonlinear program day targeting local muscular endurance under intense cardiorespiratory conditions, which may help individuals develop enhanced toleration of physiological environments where high cardiovascular demands and higher lactate concentrations are present. 相似文献