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1.
Craig W. Reynolds Tuomo T. Timonen Howard T. Holden Carl T. Hansen Ronald B. Herberman 《European journal of immunology》1982,12(7):577-582
Athymic (nude) rats were found to have increased levels of natural killer (NK) activity, 3? to 5?fold higher than in euthymic rats. Studies were performed to determine the nature of the NK cells in these animals and the basis for their increased cytotoxic reactivity. Large granular lymphocytes (LGL), which were previously shown to be the NK cells in euthymic rats, were increased 2- to 7-fold in the peripheral blood and spleen of nude rats. The LGL, enriched by centrifugation on discontinous Percoll density gradients, were shown to have augmented NK activity similar to that seen with LGL-enriched fractions from euthymic rats. These results indicate that the NK cells in euthymic and athymic rats are morphologically and functionally similar, and that the higher NK activity in nude rats appears to be mainly attributable to an increased proportion of effector cells. In a single-cell cytotoxicity assay, interferon pretreatment of LGL was shown to increase: (a) the percentage of LGL which form conjugates with target cells; (b) the percentage of conjugate-forming cells which kill; and (c) the kinetics of lysis. Different effects were seen depending on the target cell tested. 相似文献
2.
Marja -Leena Kortelainen Tuomo Lapinlampi Jorma Hirvonen 《European journal of applied physiology》1989,58(5):514-521
Summary Guinea-pigs were treated with chlorpromazine or 0.9% NaCl and exposed to +4° C or +23° C for 2 h. Hypothalamic noradrenaline
(NA), dopamine (DA), 5-hydroxytryptamine (5HT), 3-methoxy-4-hydroxyphenylethylene-glycol (MHPG), homovanillinic acid (HVA)
and 5-hydroxyindoleacetic acid (5-HIAA) were determined by high-performance liquid chromatography. Serum and urinary catecholamines,
muscle and liver glycogen and blood glucose were also measured. Chlorpromazine caused deep hypothermia at this moderately
cold temperature and slight hypothermia at room temperature. Cold increased the activity of noradrenergic and serotonergic
neurons, as indicated by the increase in hypothalamic MHPG and 5-HIAA and also the MHPG∶NA and 5-HIAA∶5-HT ratios. A tendency
towards drug-induced inhibition of hypothalamic serotonergic neurons was seen, although this was not significant. A drug-induced
inhibition of noradrenergic neurons could not be ruled out. Increased drug-induced turnover of DA was observed in the cold,
and a tendency in the same direction was seen at room temperature. Excretion of DA into the urine was induced by chlorpromazine.
The hypothermic guinea-pigs had low serum catecholamines, indicating diminished sympathetic activity, but high urinary catechols,
a sign of cold stress. 相似文献
3.
Specific and innervation-regulated expression of the intermediate filament protein nestin at neuromuscular and myotendinous junctions in skeletal muscle 总被引:8,自引:0,他引:8 下载免费PDF全文
Vaittinen S Lukka R Sahlgren C Rantanen J Hurme T Lendahl U Eriksson JE Kalimo H 《The American journal of pathology》1999,154(2):591-600
The intermediate filament proteins nestin, vimentin, and desmin show a specific temporal expression pattern during the development of myofibers from myogenic precursor cells. Nestin and vimentin are actively expressed during early developmental stages to be later down-regulated, vimentin completely and nestin to minimal levels, whereas desmin expression begins later and is maintained in mature myofibers, in which desmin participates in maintaining structural integrity. In this study we have analyzed the expression levels and distribution pattern of nestin in intact and denervated muscle in rat and in human. Nestin immunoreactivity was specifically and focally localized in the sarcoplasm underneath neuromuscular junctions (NMJs) and in the vicinity of the myotendinous junctions (MTJs), ie, in regions associated with acetylcholine receptors (AChRs). This association prompted us to analyze nestin in neurogenically and myogenically denervated muscle. Immunoblot analysis disclosed a marked overall increase of accumulated nestin protein. Similar to the extrajunctional redistribution of AChRs in denervated myofibers, nestin immunoreactivity extended widely beyond the NMJ region. Re-innervation caused complete reversion of these changes. Our study demonstrates that the expression levels and distribution pattern of nestin are regulated by innervation, ie, signal transduction into myofibers. 相似文献
4.
Immunohistochemical Study of Colorectal Tumors for Expression of a Novel Transmembrane Carbonic Anhydrase, MN/CA IX, with Potential Value as a Marker of Cell Proliferation 总被引:6,自引:4,他引:6 下载免费PDF全文
Juha Saarnio Seppo Parkkila Anna-Kaisa Parkkila Kari Haukipuro Silvia Pastorekov Jaromir Pastorek Matti I. Kairaluoma Tuomo J. Karttunen 《The American journal of pathology》1998,153(1):279-285
Carbonic anhydrase isoenzyme IX, MN/CA IX, is a recently discovered member of the carbonic anhydrase (CA) gene family with a suggested function in acid-base balance, intercellular communication, and cell proliferation. Increased expression of MN/CA IX has been observed with certain epithelial tumors. We investigated the expression of MN/CA IX in 69 colorectal neoplasms, consisting of 1 juvenile polyp, 8 hyperplastic polyps, 39 adenomatous lesions, 21 carcinomas, and 7 metastases. Tissue sections were immunostained with a monoclonal antibody specific to MN/CA IX. The proliferative activity of the tumor cells was evaluated by Ki-67 antigen immunoreactivity. The hyperplastic polyps showed a weak or moderate reaction for MN/CA IX only in the cryptal epithelium, as did the normal intestinal mucosa. The adenomas showed immunoreactivity mainly in the superficial part of the mucosa, whereas the distribution in the carcinomas and metastases was more diffuse. Comparative immunostaining of serial sections for Ki-67, a well established marker of cell proliferation, confirmed that MN/CA IX is expressed in areas with high proliferative capacity. Our results show abnormal MN/CA IX expression in colorectal neoplasms, suggesting its involvement in their pathogenesis. The co-occurrence of MN/CA IX and Ki-67 in the same tumor cells indicates its potential for use as a marker of increased proliferation in the colorectal mucosa. 相似文献
5.
Functional outcome after laparoscopic or open Nissen fundoplication: a follow-up study 总被引:3,自引:0,他引:3
Rantanen TK Salo JA Salminen JT Kellokumpu IH 《Archives of surgery (Chicago, Ill. : 1960)》1999,134(3):240-244
OBJECTIVE: To compare the results of open and laparoscopic fundoplication. DESIGN: Nonrandomized controlled study with a 3-year follow-up. PATIENTS AND METHODS: Fifty-seven consecutive patients with erosive reflux esophagitis underwent laparoscopic (30 patients) or open (27 patients) fundoplication. INTERVENTIONS: Interview by an independent person. In addition, 52 patients (91%) underwent postoperative endoscopy, and 38 patients (67%) underwent esophageal 24-hour pH recording. RESULTS: Temporary dysphagia was reported by 20 patients (67%) after laparoscopic and by 11 (41%) after open fundoplication (P = .05). There were no differences between groups concerning incidence of persistent dysphagia (20% vs 18%, respectively) and mild to no reflux symptoms (97% vs 100%, respectively). In addition, bloating (50% vs 63%, respectively) and increased flatus (77% vs 78%, respectively) were equally common. Visual analog scale scores for dysphagia, bloating, and increased flatus were 0.6, 2.4, and 4.3, respectively, in the laparoscopic and 0.6, 3.5, and 3.4, respectively, in the open groups. Normal belching ability was reported by 12 patients (40%) after laparoscopic and by 20 (74%) after open fundoplication (P = .01). Visick grade 1 or 2 was reported by 21 patients (70%) after laparoscopic and by 24 (89%) after open fundoplication (P = .08). Defective fundic wrap was detected in 4 patients (13%) in the laparoscopic and in none in the open group. In addition, abnormal results of 24-hour pH recording were found in 4 patients (22%) after laparoscopic and in 2 (10.5%) after open fundoplication. CONCLUSION: From a functional point of view, both techniques were equally effective except concerning belching ability and temporary dysphagia. 相似文献
6.
We present a series of 19 avulsions of the distal tendon of the biceps brachii muscle after a follow-up of 2 to 11 years. Ten patients with delayed diagnosis and treatment (3 weeks to 5 months) were compared with nine patients treated early (within 8 days after injury). Excellent or good results at follow-up were obtained in 9 of 10 patients in the delayed-treatment group and in all 9 patients in the early-treatment group. Nine of 10 patients in the delayed-treatment group and all patients in the early-treatment group had been able to return to their preinjury levels of activity. For reference, a meta-analysis of 147 cases reported previously was performed. Ninety percent of the patients treated with an anatomic reinsertion had excellent or good results after an average follow-up of 3 years, while similar results after 3 years were seen in 60% of the patients who had nonanatomic tendon reinsertion and in 14% of the patients who were treated nonoperatively. The delay of up to 3 years between injury and anatomic reinsertion had not compromised the result. From these data we concluded that anatomic reinsertion of the avulsed distal biceps tendon to the radius is the preferred treatment in acute as well as chronic injuries. 相似文献
7.
Virpi Rantanen Seija Grénman Kaisa Kurvinen Sakari Hietanen Misa Raitanen Stina Syrjänen 《Gynecologic oncology》1998,71(3):352-358
Objective.The correlation betweenp53tumor suppressor gene mutations and the presence of high-risk human papillomavirus (HPV) DNA with thein vitroradiosensitivity of gynecological malignancies was studied in 26 cell lines derived from gynecological cancers of 23 patients.Methods.Comparison of the intrinsic radiosensitivity was performed with mean inactivation dose (D?) determined with the 96-well plate clonogenic assay.p53mutations were investigated with polymerase chain reaction and single-strand conformation polymorphism (PCR–SSCP) analysis and direct DNA sequencing, and the presence of HPV DNA was studied with PCR using HPV consensus primers.Results. p53mutations were found in 6 of 10 vulvar squamous cell carcinoma (SCC) lines. Nine vulvar and 1 vaginal SCC cell lines were HPV DNA negative and 1 vulvar cell line was HPV 16 positive. All 4 cervical SCC lines were HPV positive and possessed the wild-typep53.Three cell lines expressed HPV 16 and 1 HPV 68. Among 10 endometrial cancer cell lines, 2 cell lines with mutantp53and 1 HPV 16 positive cell line were found. No correlation could be demonstrated between inactivation of thep53gene and radiosensitivityin vitro;the cell lines were evaluated as one group or according to their anatomical origin or histology.Conclusion.Our results indicate that inactivation of thep53gene through mutation or binding with HPV DNA does not increase the resistance of gynecological malignancies to ionizing radiationin vitro. 相似文献
8.
Hirvensalo M Lintunen T Rantanen T 《Scandinavian journal of medicine & science in sports》2000,10(1):37-41
This study investigated the continuity of life‐span physical activity by examining the predictors of the maintenance of a high level of physical activity over 8 years among subjects aged 65–84 years at the baseline, in 1988, in Jyväskylä, Finland. Age, education, marital status and chronic conditions and past physical activity were studied at the baseline. In men and women, self‐reported competitive sport participation from as early as 10–19 years of age was a significant predictor for maintaining activity in old age. Also women’s participation in recreational sports at the age of 40–64 years predicted activity. We concluded that past physical activity is strongly connected to maintaining a high level of physical activity in old age regardless of chronic conditions that may develop. 相似文献
9.
Short DNA sequences and bacterial DNA induce esophageal,gastric, and colorectal cancer cell invasion
Joonas H. Kauppila Tuomo J. Karttunen Juha Saarnio Pia Nyberg Tuula Salo David E. Graves Katri S. Selander 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2013,121(6):511-522
Toll‐like receptor 9 (TLR9) recognizes both bacterial and self‐DNA and it is abundantly expressed in the gastrointestinal tract. In this study, we investigated the influences of both bacterial DNA and specific short DNA sequences on TLR9‐mediated gastrointestinal cancer cell invasion. We assessed the effect of various DNA ligands on cellular invasion and on TLR9 and matrix metalloproteinase expression of three gastrointestinal cancer cell lines. DNA‐ligands described in this study include CpG‐ODN M362, 9‐mer (hairpin), human telomeric sequence h‐Tel22 G‐quadruplex, and bacterial DNAs from Escherichia coli and Helicobacter pylori. All of the DNAs studied were demonstrated to induce invasion in the studied cells. The DNA‐induced invasion was inhibited with a broad‐spectrum MMP inhibitor and partly also with chloroquine suggesting that it could be mediated via MMP activation, endosomal signaling, and TLR9. Interestingly, H. pylori DNA was shown to induce a more pronounced invasion in a gastric cancer cell line than in the other cell lines. Our results suggest that bacterial DNA as well as deoxynucleotides having stable secondary structures (i.e. hairpins or G‐quadruplex structures) may serve as endogenous, invasion‐inducing TLR9‐ligands and promote local progression and metastasis of cancers in the alimentary tract. 相似文献