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131.
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The main aim of the present work was to test the effects of glucose and fructose on the phosphorylation levels of proteins linked to the control of overall sperm function in two species with very different metabolic characteristics, dog and boar. Incubation of dog spermatozoa with 10mM glucose increased serine phosphorylation of proteins related to cell cycle and signal transduction including cyclins B and E, Cdk2, Cdk6, Cdc6, PYK2, c-kit, Raf-1, TRK and several protein phosphatases. Incubation of dog spermatozoa with 10mM fructose decreased serine phosphorylation levels of cyclins B and D3, Cdk1/Cdc2, Cdk2, Cdk6, Akt, PI3 kinase, ERK-1 and protein kinase C. Incubation of boar spermatozoa with glucose or fructose did not modify any of the phosphorylation patterns studied. Given that one important difference between dog and boar spermatozoa is the presence of glucokinase (GK) in dog but not in boar, GK-transfected COS7 cells were incubated with either 10mM glucose or 10mM fructose. Incubation of GK-transfected cells with fructose decreased serine phosphorylation of cyclin A, ERK-2 and Hsp-70. In contrast, incubation of control COS7 cells with fructose increased serine phosphorylation of Cdk6, Cdk1/Cdc2, protein kinase C and Hsp-70. Incubation with glucose did not induce any significant effect. Our results indicate that monosaccharides act as signalling compounds in dog spermatozoa after ejaculation through changes in the phosphorylation levels of specific proteins. One of the factors that may be related to the action of sugars is the equilibrium of the total sperm hexokinase activity, in which the presence or absence of GK appears to be relevant.  相似文献   
133.
Vaccines that drive robust T-cell immunity against Mycobacterium tuberculosis (Mtb) are needed both for prophylactic and therapeutic purposes. We have recently developed a synthetic vaccine delivery platform with Pluronic-stabilized polypropylene sulfide nanoparticles (NPs), which target lymphoid tissues by their small size (∼30 nm) and which activate the complement cascade by their surface chemistry. Here we conjugated the tuberculosis antigen Ag85B to the NPs (NP-Ag85B) and compared their efficacy in eliciting relevant immune responses in mice after intradermal or pulmonary administration. Pulmonary administration of NP-Ag85B with the adjuvant CpG led to enhanced induction of antigen-specific polyfunctional Th1 responses in the spleen, the lung and lung-draining lymph nodes as compared to soluble Ag85B with CpG and to the intradermally-delivered formulations. Mucosal and systemic Th17 responses were also observed with this adjuvanted NP formulation and vaccination route, especially in the lung. We then evaluated protection induced by the adjuvanted NP formulation following a Mtb aerosol challenge and found that vaccination with NP-Ag85B and CpG via the pulmonary route displayed a substantial reduction of the lung bacterial burden, both compared to soluble Ag85B with CpG and to the corresponding intradermally delivered formulations. These findings highlight the potential of administrating NP-based formulations by the pulmonary route for TB vaccination.  相似文献   
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BRAF p.V600E mutations are detected in greater than 50% of pediatric Langerhans cell histiocytosis (LCH) lesions. However, the use of mutation‐specific BRAF V600E immunohistochemistry (IHC) as a surrogate for molecular testing in pediatric LCH is unknown. We tested the mutation‐specific BRAF V600E monoclonal antibody (clone VE1) in formalin‐fixed, paraffin‐embedded LCH samples from 26 pediatric patients (14 males and 12 females, ages 7 mo–17 y) using allele‐specific real‐time polymerase chain reaction (PCR) with a limit of detection of 0.5% as the comparative gold standard. BRAF VE1 staining was scored for both intensity (0‐3+) and percentage of immunoreactive tumor cells (0%‐100%). BRAF VE1 immunoreactivity was determined using both lenient (≥1+, ≥1%) and stringent (≥2+, ≥10%) scoring criteria. Using lenient‐scoring criteria, we found that the sensitivity and specificity of IHC compared with allele‐specific real‐time PCR were 100.0% and 18.2%, respectively. The poor specificity of lenient IHC analysis was attributable to weak, 1+ staining in both BRAF‐mutated and wild‐type LCH. Using stringent‐scoring criteria, we found that specificity improved to 100.0% at the expense of sensitivity that decreased to 80.0%. Stringent scoring generated 3 false‐negative results, but in all cases, neoplastic tissue comprised less than 5% of the stained section and/or the specimen was decalcified. In conclusion, highly sensitive molecular assays remain the gold standard for BRAF mutation analysis in LCH paraffin‐embedded lesions. To avoid false‐positive results, unequivocal VE1 staining of 2+ intensity in greater than or equal to 10% neoplastic histiocytes is required. However, negative VE1 results require additional studies to exclude false‐negatives, and stringent‐scoring criteria may not be optimal for scant or decalcified specimens.  相似文献   
137.
Basic dosimetric data for the Walstam CDC.K-type low dose rate 137Cs sources in water have been calculated using Monte Carlo techniques. These sources, CDC.K1 -K3 and CDC.K4, are widely used in a range of applicators and moulds for the treatment of intracavitary and superficial cancers. Our purpose is to improve existing data about these sources using the Monte Carlo simulation code GEANT3. Absolute dose rate distributions in water have been calculated around these sources and are presented as conventional 2D Cartesian look-up tables. Also the AAPM Task Group 43 formalism for dose calculation has been applied. The calculated dose rate constant for the CDC.K1-K3 source is A = 1.106 +/- 0.001 cGy h(-1) U(-1), and for the CDC.K4 source, A = 1.092 +/- 0.001 cGy h(-1) U(-1). The anisotropy of the sources are accurately studied and F(r, theta) tables are given. Also phi an(r) factors are presented. The radial dose functions are given as a polynomial fit to the calculated data up to 15 cm. Best-fit values of coefficients suitable for use in Sievert integral calculations have been derived.  相似文献   
138.
In recent years, the use of high dose rate (HDR) after-loader machines has greatly increased due to the shift from traditional Cs-137/Ir-192 low dose rate (LDR) to HDR brachytherapy. The method used to calculate the required concrete and, where appropriate, lead shielding in the door is based on analytical methods provided by documents published by the ICRP, the IAEA and the NCRP. The purpose of this study is to perform a more realistic kerma evaluation at the entrance maze door of an HDR bunker using the Monte Carlo code GEANT4. The Monte Carlo results were validated experimentally. The spectrum at the maze entrance door, obtained with Monte Carlo, has an average energy of about 110 keV, maintaining a similar value along the length of the maze. The comparison of results from the aforementioned values with the Monte Carlo ones shows that results obtained using the albedo coefficient from the ICRP document more closely match those given by the Monte Carlo method, although the maximum value given by MC calculations is 30% greater.  相似文献   
139.
Functional fits for the anisotrophy function and the radial dose function, have been studied, in a previous work, in order to characterize dose-rate distributions around some of the high-intensity 192Ir sources. The purpose of the present work is to complete the previous one in order to include all the existing HDR and PDR 192Ir sources. The sources addressed here are: the Buchler source from Amersham, the 12i and Plus PDR sources and the 12i and Plus HDR sources from GammaMed, and the new VariSource HDR source wire model VS2000 from Varian Oncology Systems.  相似文献   
140.
Erythromycin base was tested by brushing a solution onto the skin in various models of non-immune and immune inflammation produced in mouse ear, namely inflammations induced by croton oil and cantharidin, primary irritation by picryl chloride, and contact hypersensitivity reactions to oxazolone and picryl chloride. On the non-immune inflammations, erythromycin displayed a greater effect than indomethacin, phenylbutazone or acetylsalicylic acid, though less than that of hydrocortisone acetate. It inhibited the hypersensitivity reactions less well. These results suggest some participation of an anti-inflammatory mechanism in the clinical effectiveness of cutaneously applied erythromycin base in some forms of acne.  相似文献   
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