The effects of insulin, transferrin and androgens on rat prostate explants in serum-free organ culture

A model previously developed in our laboratory to culture rat prostate explants in serum-free chemically-defined medium was used to evaluate the direct influence of potential regulators. The aim of the present work was to verify the effects of insulin (I) and transferrin (Tr), two hormones considered as essential in other serum-free culture systems, and three androgenic hormones, since the prostate is known to be androgen-dependent. Explants of rat prostate were cultured for five days in serum-free Leibovitz's L-15 medium (37 degrees C, 95% air-5% CO2). The addition of Tr (50 micrograms/ml) had no effect, but I (5 micrograms/ml) significantly increased DNA synthesis. This influence was amplified by combination of the two hormones. However, protein synthesis was only slightly stimulated. Testosterone (T) or androstanediol significantly increased DNA synthesis when compared to corresponding control values at five days. In combination with I plus Tr, each hormone showed potentiated effects, particularly T with a twofold increase over day 0 values. When dihydrotestosterone was added singly, the incorporation of 3H-thymidine was stimulated by 300% over control values at five days, and by 100% over values in uncultured explants. This influence was maximal since it was not improved by I plus Tr. Protein synthesis was increased significantly by the triple combination. In addition, each androgen as well as the combination of I plus Tr had a positive influence on explant morphology. The above conditions optimize the present culture system and establish its usefulness as a valuable tool to study the direct influence of different effectors in prostate metabolism and to eventually identify putative cancer markers.     

Pulsatile ocular blood flow variations with axial length and refractive error

Benign symmetric lipomatosis (BSL), also known as Madelung's disease, is a rare condition and characterized by diffuse but painless growth of unencapsulated lipomas. A close correlation to alcohol and nicotine abuse, metabolic disturbances and malignant tumours have been observed. Surgical treatment is frequently followed by recurrence, nevertheless, it can yield satisfactory functional and cosmetic results. A case of BSL with uncommonly distributed tumors is reported.     

Detection of Tn, sialosyl-Tn and T antigens in hereditary nonpolyposis colorectal cancer

The simple mucin-type carbohydrate antigens Tn, sialosyl-Tn, T and the 'cryptic' sialylated variant of the last represent the mucin core oligosaccharide structures that are produced in the initial steps of the mucin biosynthetic pathway. Utilizing monoclonal antibodies anti-Tn antigen (HB-Tn1), anti-sialosyl-Tn antigen (HB-STn1), anti-T antigen (HB-T1) and the biotinylated Amaranthus caudatus agglutinin (ACA), we have investigated the expression of the simple mucin-type carbohydrate antigens in hereditary nonpolyposis colorectal cancer (HNPCC; 15 cases) compared with sporadic colorectal cancer (CRC; 60 cases) and normal colonic mucosa (30 cases). A variable positivity of Tn, sialosyl-Tn, T and the cryptic sialylated form of this latter antigen was encountered in both HNPCC and sporadic CRC cases; in addition, in normal colonic mucosa a constant reactivity was encountered only for Tn and the cryptic sialylated form of T, while negative results were always obtained for sialosyl-Tn and T antigens. Statistical analysis, performed using a Chi-square test, showed significantly lower (P = 0.037) expression of sialosyl-Tn and higher (P = 0.022) expression of T in HNPCC than in sporadic CRC, suggesting a greater presence of beta 1,3 galactosyltransferase activity in HNPCC than in sporadic CRC. We were unable to identify a peculiar phenotype for HNPCC with simultaneous evaluation of reactivity for HB-Tn1, HB-STn1, HB-T1 and ACA; the biological significance of the preferential expression of T antigen in HNPCC remains to be investigated.     

Protein kinase C activity in the hippocampus following spatial learning tasks in mice

We have tested the effect of several bile acids on the proliferation and differentiation of the HL60 human promyelocytic leukemia cell line in vitro. Deoxycholate, chenodeoxycholate and lithocholic acid caused dose-dependent inhibition of cell proliferation and induction of differentiation along the monocyte/macrophage pathway as determined by morphology, NBT test, non-specific esterase, and staining by monoclonal antibodies against specific cell-surface antigens. Optimal effects were obtained at 100, 75, and 60 microM of the 3 bile acids respectively. Cell-cycle flow-cytometric analysis showed that a substantial fraction of HL60 cells accumulated at the G0/G1 transition. Protein-kinase-C inhibitors such as sphinganine and H-7 inhibited the differentiation-inducing effect of bile acids, suggesting a possible role for PKC in this regulation. When bile acids were combined with non-effective concentrations of all-trans retinoic acid, enhancement of the monocytic differentiation of THP-1 human leukemia cells was observed. Our findings demonstrate induction of tumor-cell differentiation by bile acids, compounds that present minimal undesirable effects in humans.     

Influence of water and accelerated aging on the shear fracture properties of glass/epoxy composite

The degradation of interlaminar shear strength and shear fracture toughness of glass/epoxy composites due to uptake of distilled water and sea water has been studied. The composites were immersed in water for up to eight months at temperatures up to 70 °C. Unreinforced matrix resin samples were also immersed for periods up to 2 years. Sea water was absorbed less rapidly than distilled water. Weight gains below 1% did not influence the shear strength while higher weight gains reduced shear strength up to 25%. The loss in apparent interlaminar shear strength was uniquely related to specimen weight gain. Mode II fracture toughness, G _IIc, also decreased with increasing immersion time after an initial incubation period, but the accelerated tests were found to reduce G _IIc less than the room temperature tests at comparable weight gains.     

Branching and pruning: An optimal temporal POCL planner based on constraint programming

A key feature of modern optimal planners such as graphplan and blackbox is their ability to prune large parts of the search space. Previous Partial Order Causal Link (POCL) planners provide an alternative branching scheme but lacking comparable pruning mechanisms do not perform as well. In this paper, a domain-independent formulation of temporal planning based on Constraint Programming is introduced that successfully combines a POCL branching scheme with powerful and sound pruning rules. The key novelty in the formulation is the ability to reason about supports, precedences, and causal links involving actions that are not in the plan. Experiments over a wide range of benchmarks show that the resulting optimal temporal planner is much faster than current ones and is competitive with the best parallel planners in the special case in which actions have all the same duration.¹     

Concealed weapon detection and visualization in a synthesized image

Images acquired by heterogeneous image sensors may provide complementary information about the scene, for instance, the visual image can provide personal identification information like the facial pattern while the infrared (IR) or millimeter wave image can detect the suspicious regions of concealed weapons. Usually, a technique, namely multiresolution pixel-level image fusion is applied to integrate the information from multi-sensor images. However, when the images are significantly different, the performance of the multiresolution fusion algorithms is not always satisfactory. In this study, a new strategy consisting of two steps is proposed. The first step is to use an unsupervised fuzzy k-means clustering to detect the concealed weapon from the IR image. The detected region is embedded in the visual image in the second step and this process is implemented with a multiresolution mosaic technique. Therefore, the synthesized image retains the quality comparable to the visual image while the region of the concealed weapon is highlighted and enhanced. The experimental results indicate the efficiency of the proposed approach.This material is based on part of the work carried out at the SPCR laboratory of Lehigh University and the work is partially supported by the U. S. Army Research Office under grant number DAAD19-00-1-0431. The content of the information does not necessarily reflect the position or the policy of the federal government, and no official endorsement should be inferred.     

Cortical cholinergic impairment and behavioral deficits produced by kainic acid lesions of rat magnocellular basal forebrain.

The rat magnocellular basal forebrain (MNBF) is homologous to the human nucleus basalis of Meynert, a structure implicated in the cholinergic hypothesis of cognitive impairment in Alzheimer's disease (AD). In the present study, 18 male Sprague-Dawley rats with kainic acid lesions in the MNBF were compared with 6 unoperated controls, 10 sham-operated controls, and 6 controls injected with kainic acid in the cortical area directly above the MNBF. MNBF lesions depleted choline acetyltransferase in cortex but not in striatum or hippocampus. Cortical dopamine levels were unchanged; serotonin levels were unchanged in hippocampus and parietal cortex but decreased in frontal cortex. Compared with controls, MNBF-lesioned Ss were impaired in 24-hr retention, but not acquisition, of a passive avoidance task with escapable footshock. The groups did not differ in mean number of daily avoidances on a barpress active avoidance task, although learning was slower in MNBF-lesioned Ss. In a serial spatial discrimination reversal test, MNBF-lesioned Ss performed significantly worse than controls. This model may be useful for studying the role of the cholinergic system in memory and possibly for developing treatment strategies to alleviate the cognitive dysfunction of AD. (63 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)