Effect of chronic duodenal ulceration and its treatment with lanzoprazole or sucralfate on gastroduodenal mucosal protein turnover and TGF-alpha, bFGF, and EGF receptor expression in humans

In order to investigate whether chronic duodenal ulcer disease is a consequence of disturbed mucosal turnover and growth factor expression, we studied 16 patients with duodenal ulcers before, during, and after endoscopic healing with lansoprazole or sucralfate. Before treatment, gastric fundal and antral mucosal protein turnover rates were higher in patients than controls, without parallel increases in growth factors. Both forms of therapy produced similar changes, with overall increases in duodenal mucosal turnover and transforming growth factor-alpha (TGF-alpha) and epidermal growth factor receptor (EGF-r) levels. Measurements after healing showed persistent elevations of mucosal turnover in the antrum and duodenum and depressions of basic fibroblast growth factor (bFGF) in gastric fundal and duodenal mucosa. We conclude that mucosal turnover is abnormally high in patients with chronic duodenal ulcer disease and is not easily explained by growth factor changes. The failure of lansoprazole and sucralfate to normalize rates, despite endoscopic healing, may explain the high ulcer relapse rates in non-HP-eradicated patients.     

Major histocompatibility complex class II-dependent antigen presentation by human intestinal endothelial cells

BACKGROUND & AIMS: In the normal gut, human intestinal microvascular endothelial cells (HIMECs) express major histocompatibility complex (MHC) class II molecules. Enhanced expression is found in chronic inflammation. We examined the cytokine regulation of MHC class II molecules and the associated invariant chain (Ii) in HIMECs and investigated whether such cells can process and present a complex protein antigen to T cells. METHODS: Enzyme-linked immunosorbent assay, flow cytometry, immunoelectron microscopy, as well as T-cell activation assay with HIMECs and HLA-DR-restricted T-cell clones were employed. RESULTS: In unstimulated HIMEC monolayers, HLA-DR, -DP, and -DQ and Ii were undetectable at the protein level, but interferon gamma (IFN-gamma) (100 U/mL) induced expression that peaked for DR after 2-3 days, for DP after 4-6 days, for DQ after 10-12 days, and for Ii after 2-3 days. Tumor necrosis factor alpha had no effect alone but enhanced class II expression in combination with IFN-gamma, most notably for DQ and DP. HLA-DR3-restricted and Mycobacterium tuberculosis heat shock 65-kilodalton-specific T-cell clones were activated to produce IFN-gamma in response to relevant antigen presented by IFN-gamma-treated HIMECs. This response was inhibited by blocking monoclonal antibody to HLA-DR and by chloroquine when compared to professional antigen-presenting cells, HIMECs activated T-cell clones quite efficiently. CONCLUSIONS: These data suggest that microvascular endothelial cells can present complex protein antigens in the human gut.     

Sharp, local synchrony among putative feed-forward inhibitory interneurons of rabbit somatosensory cortex

Many suspected inhibitory interneurons (SINs) of primary somatosensory cortex (S1) receive a potent monosynaptic thalamic input (thalamocortical SINs, SINstc). It has been proposed that nearly all such SINstc of a S1 barrel column (BC) receive excitatory synaptic input from each member of a subpopulation of neurons within the topographically aligned ventrobasal (VB) thalamic barreloid. Such a divergent and convergent network leads to several testable predictions: sharply synchronous activity should occur between SINstc of a BC, sharp synchrony should not occur between SINstc of neighboring BCs, and sharp synchrony should not occur between SINs or other neurons of the same BC that do not receive potent monosynaptic thalamic input. These predictions were tested by cross-correlating the activity of SINstc of the same and neighboring BCs. Correlations among descending corticofugal neurons of layer 5 (CF-5 neurons, identified by antidromic activation) and other neurons that receive little or no monosynaptic VB input also were examined. SINs were identified by a high-frequency (>600 Hz) burst of three or more spikes elicited by VB stimulation and had action potentials of short duration. SINstc were further differentiated by short synaptic latencies to electrical stimulation of VB thalamus (<1.7 ms) and to peripheral stimulation (<7.5 ms). The above predictions were confirmed fully. 1) Sharp synchrony (+/-1 ms) was seen between all SINstc recorded within the same BC (a mean of 4.26% of the spikes of each SINtc were synchronized sharply with the spikes of the paired SINtc). Sharp synchrony was not dependent on peripheral stimulation, was not oscillatory, and survived general anesthesia. Sharp synchrony was superimposed on a broader synchrony, with a time course of tens of milliseconds. 2) Little or no sharp synchrony was seen when CF-5 neurons were paired with SINstc or other neurons of the same BC. 3) Little or no sharp synchrony was seen when SINstc were paired with other SINstc located in neighboring BCs. Intracellular recordings obtained from three SINs in the fully awake state supported the assertion that SINs are GABAergic interneurons. Each of these cells met our extracellular criteria for identification as a SIN, each had a spike of short duration (0.4-0.5 ms), and each responded to a depolarizing current pulse with a nonadapting train of action potentials. These results support the proposed network linking VB barreloid neurons with SINstc within the topographically aligned BC. We suggest that sharp synchrony among SINstc results in highly synchronous inhibitory postsynpatic potentials (IPSPs)in the target neurons of these cells and that these summated IPSPs may be especially effective when excitatory drive to target cells is weak and asynchronous.     

老瓶装新酒--成都电信"114"转型"号码百事通"

“114”变身“号码百事通”探索转型之路“114”无疑是必须转型的,因为社会进步需要“114”转型。信息的交流沟通媒介已由过去的语音扩展到今天的短信、互联网、IPTV、3G等等,语音报号只是最基础的服务项目,未来中国电信必须为用户提供全方位服务方式。只有通过电信服务的转型,提供更灵活更丰富的用户服务模式才能符合用户对服务的期望,才能体现中国电信“用户至上,用心服务”的服务宗旨。成都电信早在2004年就敏锐地意识到了这一点,并且坚定不移地实施了“114”的转型,首开中国电信“114”转型“号码百事通”业务的先河。2004年,成都电信…     

Short-latency auditory evoked potentials in infants with otitis media

Auditory brain-stem potential findings in 154 healthy infants and infants with different forms of middle-ear pathological conditions (306 ears) were indicative of the inflammatory process influence on the parameters of auditory reception in most cases. The changes in the waves' forms and intraoperative morphological findings in the middle ear were correlated. Objective audiometry allows definite determination of the middle ear trouble which is important in diagnosis of latent otitis in infants who are especially prone to this disease.     

A mass spectrometric solution to the address problem of combinatorial libraries

The molecular weights of femtomole quantities of small peptides attached to polystyrene beads have been determined with imaging time-of-flight secondary ion mass spectrometry. The analysis is made possible by the selective clipping of the bond linking the peptide to a bead with trifluoroacetic acid vapor before the secondary ion mass spectrometry assay. The approach can be applied to large numbers of 30- to 60-micrometer polystyrene beads for the direct characterization of massive combinatorial libraries.     

FECAL COLIFORM CONTAMINATION OF BEEF CARCASSES DURING THE SLAUGHTERING PROCESS

The purpose of this study was to determine the fecal coliform counts of beef carcasses during different stages in the slaughter process. A total of nine carcasses were selected at random in the abattoir. The samples were taken by excision from three different sites; rump, brisket and shoulder. The samples were collected from the same carcasses at four different stages of processing; after dressing, after evisceration, after washing and after chilling for 24 h in a chilling room. The processing steps did not increase the fecal coliform counts on the rump samples. There were no significant differences in the samples of rump and shoulder among different processing steps. The contamination level of the brisket after washing was significantly higher than other processing steps. Brisket and shoulder parts are critical points for microbiological sampling as these sites showed higher microbial counts after chilling steps. The data obtained have relevance for the planning of washing methods for the production of clean and safe carcasses.     

The antioxidant properties of lycopene

The antioxidant properties of the carotenoid lycopene were compared in three different model oxidative systems. In egg yolk liposomes, in the presence of 2.5 mM FeSO4 and 200 mM ascorbate, lycopene, alpha-tocopherol, and beta-carotene inhibited the accumulation of lipid peroxidation products reacting with 2-thiobarbituric acid (TBARS) in a dose-dependent mode, with the concentration of half-inhibition being 80, 30 and 130 mM, respectively. In the liposomes subjected to illumination with a He-Ne laser (632.8 nm) at a dose of 10.5 J/cm2, in the presence of 32.5 micrograms/ml hematoporphyrin derivatives (Fotogem, NIOPIC, Russia) TBARS accumulated, and this effect was inhibited by lycopene, alpha-tocopherol, and dihydroquercetin with approximately equal efficiencies (the half-inhibition concentrations were 10(-5) mM). In both systems studied, sodium azide at a concentration of 10 mM inhibited the TBARS accumulation by no more than 20%. Apparently, the inhibitory action of not only alpha-tocopherol, but also beta-carotene and lycopene was the result of their antiradical action, rather than quenching of the singlet oxygen in an aqueous medium. The introduction of lycopene, as well as beta-carotene in liposomes subjected to Fe(2+)-induced lipid peroxidation decreased the chemiluminescence (CL) intensity at the stage of CL slow flash, with no essential influence on the lag period. These data suggest that the effect of lycopene on lipid peroxidation was the result of its interaction with free radicals rather than chelating ferrous ions. The antiradical activity of lycopene was also confirmed by the method of luminol photochemiluminescence (PCL). Lycopene increased the PCL lag period (L) and decreased the PCL amplitude (A), which implies its antiradical and SOD-like activity in this system.