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31.
In vivo-applied sodium selenide or sodium selenite causes the appearance of zinc-selenium nanocrystals in places where free or loosely bound zinc ions are present. These nanocrystals can in turn be silver enhanced by autometallographic (AMG) development. The selenium method was introduced in 1982 as a tool for zinc-ion tracing, e.g., in vesicular compartments such as synaptic vesicles of zinc-enriched (ZEN) terminals in the central nervous system, and for visualization of zinc ions in ZEN secretory vesicles of, e.g., somatotrophic cells in the pituitary, zymogene granules in pancreatic acinar cells, beta-cells of the islets of Langerhans, Paneth cells of the crypts of Lieberkühn, secretory cells of the tubuloacinar glands of prostate, epithelium of parts of ductus epididymidis, and osteoblasts. If sodium selenide/selenite is injected into brain, spinal cord, spinal nerves containing sympathetic axons, or intraperitoneally, retrograde axonal transport of zinc-selenium nanocrystals takes place in ZEN neurons, resulting in accumulation of zinc-selenium nanocrystals in lysosomes of the neuronal somata. The technique is, therefore, also a highly specific tool for tracing ZEN pathways. The present review includes an update of the 1982 paper and presents evidence that only zinc ions are traced with the AMG selenium techniques if the protocols are followed to the letter.  相似文献   
32.
Objective: To examine the relation between different types of alcoholic drinks and upper digestive tract cancers (oropharyngeal and oesophageal). Design: Population based study with baseline assessment of intake of beer, wine, and spirits, smoking habits, educational level, and 2-19 years’ follow up on risk of upper digestive tract cancer. Setting: Denmark. Subjects: 15 117 men and 13 063 women aged 20 to 98 years. Main outcome measure: Number and time of identification of incident upper digestive tract cancer during follow up. Results: During a mean follow up of 13.5 years, 156 subjects developed upper digestive tract cancer. Compared with non-drinkers (drinkers of <1 drink/week), subjects who drank 7-21 beers or spirits a week but no wine were at a risk of 3.0 (95% confidence interval 1.5 to 6.1), whereas those who had the same total alcohol intake but with wine as ⩾30% of their intake had a risk of 0.5 (0.2 to 1.4). Drinkers of >21 beers and spirits but no wine had a relative risk of 5.2 (2.7 to 10.2) compared with non-drinkers, whereas those who drank the same amount, but included wine in their alcohol intake, had a relative risk of 1.7 (0.6 to 4.4). Conclusion: A moderate intake of wine probably does not increase the risk of upper digestive tract cancer, whereas a moderate intake of beer or spirits increases the risk considerably.

Key messages

  • Alcohol is a strong risk factor for oropharyngeal and oesophageal cancer
  • The carcinogenic effect of alcohol has been assumed to be independent of type of alcohol drunk
  • Resveratrol, a substance in grapes and wine, has been shown to inhibit the initiation, promotion, and progression of cancer
  • Wine drinkers may be at a lower risk of developing upper digestive tract cancer than drinkers who have a similar intake of beer or spirits
  相似文献   
33.
Transfected DNA is mutated in monkey, mouse, and human cells.   总被引:45,自引:17,他引:28       下载免费PDF全文
Papovavirus-based shuttle vectors containing the bacterial lacI gene were used to show that a mutation frequency in the range of 1% occurs in lacI when such vectors are transfected into COS7 and CV-1 simian cells, NIH 3T3, 3T6, L, and C127 mouse cells, and human 293 and HeLa cells. This frequency is approximately four orders of magnitude higher than the spontaneous mutation frequency in either mammalian or bacterial cells. The mutations are predominantly base substitutions and deletions and also include insertions from the mammalian genome. Time course experiments argue that mutagenesis occurs soon after arrival of the DNA into the nucleus. However, replication of the vector is not required since mutations occur even when the vector lacks all viral sequences. The high mutation frequency appears to be the characteristic outcome of transfection of DNA into mammalian cells.  相似文献   
34.
Summary The hepatic 1-macroglobulin receptor (2MR)/low density lipoprotein receptor-related protein (LRP) binds and endocytoses 2-macroglobulin-proteinase complexes in plasma. In addition, it binds lipoproteins, a novel 40 kDa protein, and complexes between plasminogen activators and plasminogen activator inhibitor type-1. This study shows, for the first time, the tissue distribution of 2MR/LRP as determined by immunohistochemistry with specific monoclonal antibodies. The analysis revealed 2MR/LRP-expression in a restricted spectrum of cell types, including neurons and astrocytes in the central nervous system, epithelial cells of the gastrointestinal tract, smooth muscle cells, fibroblasts, Leydig cells in testis, granulosa cells in ovary, and dendritic interstitial cells of kidney. Monocytederived cells displayed marked 2MR/LRP expression in the phagocytes of liver, lung and lymphoid tissues, but no or low expression in antigen-presenting cells including Langerhans' cells of the skin. The high abundance of 2MR/LRP in certain cell types of most organs suggests two main routes for 2MR/LRP ligand clearance: (1) systemic removal in liver of circulating ligands, and (2) non-hepatic interstitial removal in different organs, including the brain.  相似文献   
35.
Seven female rabbits had myometrial autografts transplanted into ear-chambers. The electrical activity of the graft was recorded and mechanical activity observed. Vasoactive intestinal polypeptide (VIP) dose-dependently inhibited myometrial activity induced by prostaglandin-F. This evidence and the occurrence of “VIPergic” nerve fibres, which seem to innervate the myometrial cells, suggest that VIP may play a physiological role in the local control of the myometrial activity.  相似文献   
36.
Terminally blocked (L-Pro-Aib)n and Aib-(L-Pro-Aib)n sequential oligopeptides are known to form right-handed β-bend ribbon spirals under a variety of experimental conditions. Here we describe the results of a complete CD and ir characterization of this subtype of 310-helical structure. The electronic CD spectra were obtained in solvents of different polarity in the 260-180 nm region. The vibrational CD and Fourier transform ir (FTIR) spectra were measured in deuterochloroform solution in the amide I and amide II (1750-1500 cm?1) regions. The critical chain length for full development of the β-bend ribbon spiral structure is found to be five to six residues. Spectral effects related to concentration-induced stabilization of the structures of the longer peptides were seen in the resolution-enhanced FTIR spectra. Comparison to previous studies of (Aib)n and (Pro)n oligomers indicate that the low frequency of the amide I mode is due to the interaction of secondary and tertiary amide bonds and not to a strong difference in conformation from a regular 310-helix. © 1995 John Wiley & Sons, Inc.  相似文献   
37.
Bacteraemia is associated with significant morbidity and mortality and timely access to relia-ble information is essential for health care administrators. Therefore, we investigated the complete-ness of bacteraemia registration in the Danish National Patient Registry (DNPR) containing hospital discharge diagnoses and surgical procedures for all non-psychiatric patients. As gold standard we identified bacteraemia patients in three defined areas of Denmark (~2.3 million inhabitants) from 2000 through 2011 by use of blood culture data retrieved from electronic microbiology databases. Diagnoses coded according to the International Classification of Diseases, version 10, and surgical procedure codes were retrieved from the DNPR. The codes were categorized into seven groups, ranked a priori according to the likelihood of bacteraemia. Completeness was analysed by contin-gency tables, for all patients and subgroups. We identified 58,139 bacteraemic episodes in 48,450 patients; 37,740 episodes (64.9%) were covered by one or more discharge diagnoses within the sev-en diagnosis/surgery groups and 18,786 episodes (32.3%) had a code within the highest priority group. Completeness varied substantially according to speciality (from 17.9% for surgical to 36.4% for medical), place of acquisition (from 26.0% for nosocomial to 36.2% for community), and mi-croorganism (from 19.5% for anaerobic Gram-negative bacteria to 36.8% for haemolytic strepto-cocci). The completeness increased from 25.1% in 2000 to 35.1% in 2011. In conclusion, one third of the bacteraemic episodes did not have a relevant diagnosis in the Danish administrative registry recording all non-psychiatric contacts. This source of information should be used cautiously to iden-tify patients with bacteraemia.  相似文献   
38.
39.
Collagen metabolism in the focal degenerated cartilage from immature dogs with degenerative joint disease was compared with that in the adjacent ‘normal’ cartilage of the same joint surface. The deposition of collagen into the cartilage in vitro as measured by accumulation of hydroxyl [14C]proline was decreased in the early and in advanced stages of cartilage degeneration. The deposition of collagen into cartilage in vivo as measured by the accumulation of hydroxy[3H]proline (intravenously injected [3H]proline) also was reduced in the degenerated cartilages of a dog with degenerative joint disease. Gel electrophoretic analysis revealed that degenerated cartilage contained less α1 collagen chains, but increased amounts of larger proteins. Degenerated cartilage contained more water, increased amounts of unidentified, non-collagenous protien. increased collagenolytic enzyme activity and fewer chondrocytes. Decreased deposition of collagen would result in collagen depletion in the foci of degenerated cartilage in joints of dogs with degenerative joint disease.  相似文献   
40.

Introduction

A key phenomenon in rheumatoid arthritis is the formation of lymphoid follicles in the inflamed synovial membrane. C-X-C motif chemokine 13 (CXCL13) is central in this process as it attracts C-X-C chemokine receptor type 5 (CXCR5)-expressing B cells and T follicular helper cells to the follicle. We here examine the role of CXCL13 and its association with disease in patients with treatment-naïve early rheumatoid arthritis.

Methods

Plasma samples from patients in the OPERA trial were examined for CXCL13 at treatment initiation and after 6 months of treatment with either methotrexate plus placebo (DMARD) (n = 37) or methotrexate plus adalimumab (DMARD + ADA) (n = 39). Treatment outcome was evaluated after 1 and 2 years. CXCL13 plasma levels in healthy volunteers (n = 38) were also examined.

Results

Baseline CXCL13 plasma levels were increased in early rheumatoid arthritis patients in comparison with healthy volunteers. Also, plasma CXCL13 correlated positively with disease activity parameters; swollen joint count 28 (rho = 0.34) and 40 (rho = 0.39), visual analog score (rho = 0.38) and simplified disease activity index (rho = 0.25) (all P <0.05). CXCL13 levels decreased a significantly twofold more in the DMARD + ADA group than in the DMARD group. Baseline CXCL13 plasma levels in the DMARD group correlated inversely with disease activity parameters; disease activity score in 28 joints, four variables, C-reactive protein based (DAS28CRP) (rho = 0.58, P <0.05) at 12 months. High baseline CXCL13 was associated with remission (DAS28CRP less than 2.6) after 2 years.

Conclusions

In treatment-naïve early rheumatoid arthritis patients, plasma CXCL13 levels were associated with joint inflammation. Furthermore, patients with high baseline plasma CXCL13 levels had an improved chance of remission after 2 years. We propose that high CXCL13 concentrations indicate recent onset of inflammation that may respond better to early aggressive treatment. Thus, high levels of CXCL13 could reflect the ‘the window of opportunity’ for optimal treatment effect.

Trial registration

Clinicaltrial.gov NCT00660647. Registered 10 April 2008  相似文献   
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