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1.
Feng He Yuanjun Ma Shi Li Haozhe Ren Qian Liu Xiaohua Chen Hui Miao Tao Ye Qian Lu Zuge Yang Tianle Li Xin Tong Hongxu Yang Mian Zhang Helin Wang Yazhou Wang Shibin Yu 《Journal of bone and mineral research》2022,37(5):1044-1055
Temporomandibular joint osteoarthritis (TMJOA) is a chronic degenerative disease for which the underlying mechanism still remains unclear. Compared with apoptosis and autophagy, necroptosis causes greater harm to tissue homeostasis by releasing damage-associated molecular patterns (DAMPs). However, the role of necroptosis and downstream key DAMPs in TMJOA is unknown. Here, rodent models of TMJOA were established by the unilateral anterior crossbite (UAC). Transmission electron microscopy (TEM) and immunohistochemistry of receptor interacting protein kinase 3 (RIPK3)/phosphorylation of mixed lineage kinase domain-like protein (pMLKL) were conducted to evaluate the occurrence of necroptosis in vivo. The therapeutic effects of blocking necroptosis were achieved by intra-articularly injecting RIPK3 or MLKL inhibitors and using RIPK3 or MLKL knockout mice. In vitro necroptosis of condylar chondrocyte was induced by combination of tumor necrosis factor alpha (TNFα), second mitochondria-derived activator of caspases (SMAC) mimetics and carbobenzoxy-valyl-alanyl-aspartyl-[O-methyl]- fluoromethylketone (z-VAD-fmk). The possible DAMPs released by necroptotic chondrocytes were screened by quantitative proteomics and blocked by specific antibody. Translucent cytosol, swollen organelles, and ruptured cell membranes, features of necroptosis, were frequently manifested in chondrocytes at the early stage of condylar cartilage degeneration in TMJOA, which was accompanied by upregulation of RIPK3/pMLKL. Inhibiting or knocking out RIPK3/MLKL significantly prevented cartilage degeneration. DAMPs released by necroptotic condylar chondrocytes, such as syndecan 4 (SDC4) and heat shock protein 90 (HSP90), were verified. Furthermore, blocking the function of SDC4 significantly attenuated the expression of TNFα in cartilage and synovium, and accordingly increased cartilage thickness and reduced synovial inflammation. Thus, the necroptotic vicious cycle of TNFα-SDC4-TNFα contributes to cartilage degeneration and synovitis, and can serve as a potential therapeutic target for treating TMJOA. © 2022 American Society for Bone and Mineral Research (ASBMR). 相似文献
2.
M Helle H Helin P Ashorn E L Putkinen K Krohn T Wahlstr?m 《Pathology, research and practice》1992,188(1-2):74-77
The tumour antigen expression of ovarian and endometrial endometrioid carcinomas, ovarian clear-cell carcinomas as well as endometrial and cervical clear-cell carcinomas were immunohistochemically compared. Of special interest were potential differences between the endometrioid and clear-cell carcinomas of the ovary. The expression of CEA and CA 19-9 tumour antigens in all these tumour types was heterogeneous, with 10-20% of the cases being positive for CEA and 40-75% being positive for CA 19-9. In contrast, HMFG IIIC 12, a monoclonal antibody originally directed against human milk fat globule (HMFG) membrane antigens, invariably detected a corresponding antigen on every case of these tumour types. Another HMFG antibody, SM IF 3, on the other hand, detected antigenic material on all clear-cell tumour types, but only rarely on endometrioid tumours of the ovary or endometrium. While HMFG IIIC 12 detects an antigen present on all ovarian, endometrial and mammary carcinomas, antibody SM IF 3 thus appears to be more restricted in its staining patterns. Our results with both of these antibodies indicate that ovarian clear-cell carcinomas and ovarian endometrioid carcinomas have antigenic differences, which provides further evidence that they belong to different tumour entities. 相似文献
3.
4.
Andor Erdelyil Teuvo Sihvonen Pertti Helin Osmo Hänninen 《International archives of occupational and environmental health》1988,60(2):119-124
Summary Keyboard work consists mostly of dynamic contractions of the small muscles of the forearms and hands. This is accompanied by continuous activity in the arm, shoulder and neck muscles keeping the head and hand in the correct position. Eliminating the weight from the arm by means of support and the position of the arms influences the electrical activity of shoulder muscles when working at a keyboard. We studied the influence of elbow angle, as well as that of different arm supports, on electrical activity of upper trapezius muscle during keyboard work in healthy workers and persons suffering from shoulder pains. The measurements were carried out in the laboratory. EMG activities, which where measured as mean square root (RMS)-values at every 100-millisecond period in trapezius muscle when working, were lower, the greater the elbow angle. Furthermore electrical activity decreased when subjects used arm supports while working. It is evident that the static load to shoulder muscles can be lowered significantly in keyboard work, when the forearms are at an angle of at least 100 degrees and by using arm supports. The most convienient and ergonomic working position can also be found individually be the method used here. 相似文献
5.
Evaluation of a new cellulose sponge-tipped swab for microbiological sampling: a laboratory and clinical investigation
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Osterblad M Järvinen H Lönnqvist K Huikko S Laippala P Viljanto J Arvilommi H Huovinen P 《Journal of clinical microbiology》2003,41(5):1894-1900
A new type of swab (Cellswab; Cellomeda, Turku, Finland), utilizing a highly absorbent cellulose viscose sponge material, was compared to some traditional swabs. The survival of 14 aerobic and 10 anaerobic and microaerophilic bacterial species in the Cellswab, two commercial swab transport systems (Copan, Brescia, Italy, and Orion Diagnostica, Espoo, Finland), and one Dacron swab (Technical Service Consultants Ltd. [TSC], Heywood, United Kingdom) was evaluated. Bacteria were suspended in broth, into which the swabs were dipped. The Cellswab absorbed 1.3 times more fluid and released 3.5 times more fluid upon plating than the other swabs. Aerobic bacteria were stored in dry tubes, the others in transport medium, at 4 degrees C and room temperature (RT), for up to 14 days. Swab samples were transferred to plates at 0, 1, 2, 4, 7, and 14 days. For 10 strains the Cellswab yielded > or =10% of the original CFU for longer than all the other swabs. In the clinical study, the ability of the Cellswab to detect beta-hemolytic streptococci from throat samples (n = 995) was compared to that of the TSC Dacron swab. The swabs performed equally, both when their samples were transferred to plates immediately and after storage for 1 day at 4 degrees C or RT. The changes in normal microbiota after storage were also similar. The Cellswab was found to perform at least as well as ordinary swabs. It was better at storing fastidious strains, and at keeping bacteria viable for long storage times; it might well be a useful replacement or complement to ordinary swabs. 相似文献
6.
Imprint cytology in immunocytochemical analysis of oestrogen and progesterone receptors of breast carcinoma.
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H J Helin J J Isola M J Helin M J Helle K J Krohn 《Journal of clinical pathology》1989,42(10):1043-1045
Cytological imprint material from 26 mammary carcinomas was stained with monoclonal antibodies to oestrogen and progesterone receptors in an immunoperoxidase procedure. The staining result was compared with that of parallel stainings of frozen tissue sections of the same tumours. The peroxidase reactions in both techniques were semiquantitatively assessed (histoscore). In both sets of stainings the results agreed in 25 of 26 cases (oestrogen receptor: 19 positive, six negative; progesterone receptor: 14 positive, 11 negative). The histoscores of imprint preparations and cryostat sections showed a significant correlation in linear regression analysis (oestrogen receptor: r = 0.755, p less than 0.001; progesterone receptor: r = 0.740, p less than 0.001). Imprint cytology is simple, does not require expensive instruments, and no separate specimen has to be sequestered. It is especially suitable for immunocytochemical steroid receptor analysis of small breast carcinomas. 相似文献
7.
Mechanisms dependent on tryptophan catabolism regulate immune responses in primary Sjögren's syndrome
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Pertovaara M Raitala A Uusitalo H Pukander J Helin H Oja SS Hurme M 《Clinical and experimental immunology》2005,142(1):155-161
To investigate the possible role of tryptophan metabolism in immune regulation of primary Sjögren's syndrome (pSS) the serum concentrations of tryptophan and its metabolite kynurenine were measured by reverse‐phase high‐performance liquid chromatography (HPLC) in 103 patients with pSS, 56 patients with sicca symptoms and 309 healthy blood donors. The kynurenine per tryptophan ratio (kyn/trp), which reflects the activity of the indoleamine‐pyrrole 2,3‐dioxygenase (IDO) enzyme involved in tryptophan catabolism, was calculated. Both female and male patients with pSS had significantly higher serum kynurenine concentrations and kyn/trp than subjects with sicca symptoms or healthy blood donors. The median (quartile range) concentration of kynurenine in female patients with pSS was 2·41 µmol/l (1·86–3·26) compared with 1·85 µmol/l (1·58–2·38, P < 0·0001) in subjects with sicca symptoms and 1·96 µmol/l (1·65–2·27, P < 0·0001) in healthy blood donors. Their kyn/trp × 1000 was 34·0 (25·1–44·3) compared with 25·3 (21·1–31·5, P < 0·0001) in subjects with sicca symptoms and 24·3 (21·0–28·9, P < 0·0001) in healthy blood donors. Female pSS patients with high IDO activity (kyn/trp × 1000 ≥ 34·0) had significantly higher ESR, serum C‐reactive protein, serum IgA and serum beta‐2 microglobulin concentrations as well as higher serum creatinine levels, and they had positive antinuclear antibodies more frequently and presented with more American‐European consensus group criteria than those with low IDO activity (kyn/trp × 1000 < 34·0). These data suggest that mechanisms dependent on tryptophan catabolism regulate immune responses in pSS. Tryptophan degradation is enhanced in patients with pSS, and high IDO activity is associated with severity of pSS. 相似文献
8.
Increased expression of telomerase RNA component is associated with increased cell proliferation in human astrocytomas. 总被引:7,自引:1,他引:7
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P. Sallinen H. Miettinen S. L. Sallinen H. Haapasalo H. Helin J. Kononen 《The American journal of pathology》1997,150(4):1159-1164
Deregulation of telomerase, a ribonucleoprotein polymerase that compensates progressive loss of telomeric (TTAGGG)n repeats during DNA replication, has been suggested to facilitate tumorigenesis and cellular immortality by providing unlimited proliferation capacity for cancer cells. We investigated the relationship between tumor proliferation activity and in situ expression of the telomerase RNA component in 46 human grade I to IV astrocytomas. Heterogeneously distributed telomerase RNA expression was detected from all of the tumor samples as well as from normal human brain tissue. However, expression of telomerase RNA was significantly increased in highly malignant tumors (P = 0.024) and in tumors that showed increased proliferation activity determined by MIB-1 immunohistochemistry (P = 0.014). Interestingly, increased telomerase RNA levels were observed in a subgroup of grade II astrocytomas that showed significant increase in proliferation activity (P = 0.047), indicating that the telomerase RNA component is up-regulated already in early states of astrocytoma malignancy. Telomeric repeats amplification assays revealed telomerase activity in 4 of 6 glioblastomas and in 1 rapidly proliferating grade II astrocytoma. These results suggest that increased tumor proliferation activity triggers telomerase activation via mechanisms that involve increased production of the telomerase RNA component. 相似文献
9.
Sallinen M Härmä M Mutanen P Ranta R Virkkala J Müller K 《Journal of sleep research》2003,12(2):103-112
Sleep in shift work has been studied extensively in regular shift systems but to a lesser degree in irregular shifts. Our main aim was to examine the sleep-wake rhythm in shift combinations ending with the night or the morning shift in two irregular shift systems. Three weeks' sleep/work shift diary data, collected from 126 randomly selected train drivers and 104 traffic controllers, were used in statistical analyses including a linear mixed model and a generalized linear model for repeated measurements. The results showed that the sleep-wake rhythm was significantly affected by the shift combinations. The main sleep period before the first night shift shortened by about 2 h when the morning shift immediately preceded the night shift as compared with the combination containing at least 36 h of free time before the night shift (reference combination). The main sleep period before the night shift was most curtailed between two night shifts, on average by 2.9 and 3.5 h among the drivers and the controllers, respectively, as compared with the reference combination. Afternoon napping increased when the morning or the day shift immediately preceded the night shift, the odds being 4.35-4.84 in comparison with the reference combination. The main sleep period before the morning shift became 0.5 h shorter when the evening shift preceded the morning shift in comparison with the sleep period after a free day. The risk for dozing off during the shift was associated only with the shift length, increasing by 17 and 35% for each working hour in the morning and the night shift, respectively. The results demonstrate advantageous and disadvantageous shift combinations in relation to sleep and make it possible to improve the ergonomy of irregular shift systems. 相似文献
10.
Expression of human pim family genes is selectively up-regulated by cytokines promoting T helper type 1, but not T helper type 2, cell differentiation 总被引:3,自引:0,他引:3
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Cytokines are the most important inducers of T helper (Th) cell differentiation. Interleukin-12 (IL-12) and interferon-alpha (IFN-alpha) are responsible for human Th1-cell differentiation, while IL-4 is the critical cytokine promoting Th2-cell development. These two subsets of cells co-ordinate immunological responses to pathogens as well as autoimmune or allergic reactions. The pim family of proto-oncogenes encodes serine/threonine-specific kinases involved in cytokine-mediated signalling pathways in haematopoietic cells. Here we demonstrate that expression of pim-1 and pim-2 mRNAs is selectively up- or down-regulated in human cord-blood-derived CD4+ cells freshly induced to polarize towards Th1 or Th2 cells, respectively, whereas their expression is inhibited in both cell types by the immunosuppressive transforming growth factor beta (TGF-beta). Moreover, the Th1-specific cytokines IL-12 and IFN-alpha, but not the Th2-specific cytokine IL-4, transiently up-regulate pim-1 and pim-2 mRNA expression in human peripheral blood T cells and natural killer cells. In addition, the Pim-1 protein levels are strongly up-regulated by Th1-specific cytokines in all of these cell types. Taken together, our results suggest that pim genes and their protein products are involved in the early differentiation process of T helper cells. 相似文献