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81.
BackgroundThe primary objective was to compare the overall diagnostic performance, presented as detection rate of 68Ga-PSMA-HBED-CC positron emission tomography/magnetic resonance imaging (PSMA PET/MRI) versus conventional, multiparametric MRI (mpMRI) in a population of patients with biochemically recurrent prostate cancer. In conjunction with this analysis, secondary objectives included the evaluation of the detection rate stratified by PSA levels and primary treatment modality.MethodsA total of 165 PSMA PET MRI were performed from April 2018 to May 2021, of whom 108 were presenting for biochemical recurrent disease. The PSMA PET vertex to thigh were read by two different board-certified nuclear medicine physicians while the MRI head and neck, chest, abdomen, and pelvis (with dedicated, PI-RADS compliant multiparametric prostate MRI) were read by two board certified diagnostic radiologists.AnalysisPSMA PET/MRI had a higher detection rate than mpMRI when evaluating patients with biochemical recurrence (BCR) with similar results demonstrated when sub-analysis was performed using PSA levels, primary treatment modality, and time since androgen deprivation therapy. Our study also showed PSMA PET/MRI had a higher sensitivity than mpMRI.DiscussionOur findings demonstrate that PSMA PET/MRI is a better imaging modality in the detection of disease in the setting of BCR when compared to MRI alone. Combined utility with PSMA PET/MRI is a powerful tool which can aid in not only the detection of disease, but also guide in treatment planning for prostate cancer patients.  相似文献   
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N-Phthaloyl gamma-aminobutyric acid (P-GABA) was administered to Wistar rats and 24 hr rhythms of glucose, cholesterol, total protein and lactic acid levels in blood were studied under semi-natural light dark conditions. P-GABA administration caused desynchronisation of the rhythms; while glucose and lactic acid rhythms were advanced, cholesterol and total protein rhythms were delayed. Since GABA is being involved in conveying dark information to the clock, exogenous administration of P-GABA may reduce the photic information received by the clock. The results could be explained by slightly less than 1 hr daily delays (or) advances respectively which would bring the peak times to the points 21 days after the start of administration.  相似文献   
84.
Certain cells within the CNS, microglial cells and perivascular macrophages, develop from hemopoietic myelomonocytic lineage progenitors in the bone marrow (BM). Such BM-derived cells function as CNS APC during the development of T cell-mediated paralytic inflammation in diseases such as experimental autoimmune encephalomyelitis and multiple sclerosis. We used a novel, interspecies, rat-into-mouse T cell and/or BM cell-transfer method to examine the development and function of BM-derived APC in the CNS. Activated rat T cells, specific for either myelin or nonmyelin Ag, entered the SCID mouse CNS within 3-5 days of cell transfer and caused an accelerated recruitment of BM-derived APC into the CNS. Rat APC in the mouse CNS developed from transferred rat BM within an 8-day period and were entirely sufficient for induction of CNS inflammation and paralysis mediated by myelin-specific rat T cells. The results demonstrate that T cells modulate the development of BM-derived CNS APC in an Ag-independent fashion. This previously unrecognized regulatory pathway, governing the presence of functional APC in the CNS, may be relevant to pathogenesis in experimental autoimmune encephalomyelitis, multiple sclerosis, and/or other CNS diseases involving myelomonocytic lineage cells.  相似文献   
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We have investigated the implications of the rise in membrane cholesterol levels on several in vitro and in vivo properties of polyoma virus transformed rat fibroblasts (PyF), with a special emphasis on alpha5beta1 integrin functions. We show that increased membrane cholesterol causes the PyF cells to change their shape and become more bipolar in appearance. These cells also show significantly higher adhesion to the cell-binding domain of fibronectin, increased localization of alpha5beta1 integrin and talin molecules in focal adhesions and a more robust actin cytoskeleton organization. PyF cells with increased membrane cholesterol show reduced growth in vitro and tumours caused by these cells in nude mice are slow growing. These changes in the growth properties of PyF cells are reversible when the cholesterol levels of PyF cells become normal. Our results suggest that changes in membrane cholesterol levels influence the growth and morphological properties of transformed cells, which can be exploited in controlling the growth of tumours in vivo.  相似文献   
87.
Chicken riboflavin carrier protein (RCP; 219 AA) harbours four linear epitopes, constituted by the peptide residues 3-23, 64-83, 130-147 and 200-219. Antibodies to these sequences bioneutralize maternal RCP and provide protection from pregnancy in rodents. In order to overcome the major histocompatibility complex-dependent variability in immune response often encountered with use of single peptides for vaccination in genetically outbred populations, we have assembled a novel synthetic gene, incorporating in tandem the nucleotide sequences coding for all the four neutralizing epitopes of chicken RCP and expressed in Escherichia coli. The gene product, mini-RCP has been characterized for its immunogenic properties and contraceptive potential in rodents. Immunization of rabbits and rats led to generation of antibodies against individual peptide components, as determined by enzyme-linked-immunosorbent assay (ELISA). However, immunized rats carried pregnancy to term and delivered healthy offsprings. Antisera from these rats exhibited decreased affinity of binding to the native protein. These findings suggest that the prospects of covalently-linked epitope peptides need to be cautiously evaluated during the design and development of peptide-based vaccines.  相似文献   
88.
Activation of bovine platelets with thrombin and phorbol 12,13-dibutyrate (PDBu) resulted in phosphorylation of profilin on serine. The phosphorylation was inhibited when platelets were pretreated with the PI 3-kinase inhibitor, LY294002, indicating that profilin phosphorylation is a downstream event with respect to PI 3-kinase activation. Phosphorylation of profilin resulted in significant decrease in actin polymerization (16.5%), indicating an increased affinity of phosphoprofilin towards actin. The critical actin monomer concentration (Cc) increased to 260 nM in the presence of phosphoprofilin in comparison with 200 nM in the presence of profilin. The interaction of phosphoprofilin with phosphatidylinositol 4,5-bisphosphate [PI (4,5)-P2] and poly (L-proline) (PLP) was examined by monitoring the quenching of tryptophan fluorescence. Scatchard plot and binding isotherm data obtained revealed no difference in PI (4,5)-P2 binding between profilin and phosphoprofilin (Kd=20.4 microM), while poly (L-proline)-binding studies indicated a sixfold decrease (27.34 microM for profilin and 4.73 microM for phosphoprofilin) in Kd with phosphoprofilin. In vivo studies with platelets indicated an increased association of p85alpha, the regulatory subunit of PI 3-kinase with phosphoprofilin over profilin. Overall, the data presented conclude that profilin phosphorylated under in vivo conditions and phosphorylation depends upon activation of PI 3-kinase. Phosphoprofilin exhibited increased affinity to poly (L-proline) sequences both in vitro and in vivo.  相似文献   
89.
The study of complex biological questions through comparative proteomics is becoming increasingly attractive to plant biologists as the rapidly expanding plant genomic and expressed sequence tag databases provide improved opportunities for protein identification. This review focuses on practical issues associated with comparative proteomic analysis, including the challenges of effective protein extraction and separation from plant tissues, the pros and cons of two-dimensional gel-based analysis and the problems of identifying proteins from species that are not recognized models for functional genomic studies. Specific points are illustrated using data from an ongoing study of the tomato and pepper fruit proteomes.  相似文献   
90.
The purpose of this study was to assess the progressive changes of nasal symmetry, growth, and relapse after presurgical nasoalveolar molding and primary cheiloplasty in unilateral complete cleft lip/palate infants. Twenty-five consecutive complete unilateral cleft lip/palate infants were included. All the infants underwent nasoalveolar molding before primary cheiloplasty. Standard 1:1 ratio basilar photographs were taken before and after nasoalveolar molding, 1 week after cheiloplasty, and yearly for 3 years. Linear measurements were made directly on the photographs. The results of this study revealed that the nasal asymmetry was significantly improved after nasoalveolar molding and was further corrected to symmetry after primary cheiloplasty. After the primary cheiloplasty, the nasal asymmetry significantly relapsed in the first year postoperatively and then remained stable and well afterward. The relapse was the result of a significant differential growth between the cleft and noncleft sides in the first year postoperatively. To compensate for relapse and differential growth, the authors recommend (1) narrowing down the alveolar cleft as well as possible by nasoalveolar molding, (2) overcorrecting the nasal vertical dimension surgically, and (3) maintaining the surgical results using a nasal conformer.  相似文献   
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