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81.
Unsaturated polyester (UP) cement caused allergic contact dermatitis in car repair work. The resin was a condensate of polyols and maleic anhydride with reactive solvent, auxiliary substances, and inorganic reinforcement substances. To identify the causative chemicals, the cement was tested on a sensitized patient. For analysis, samples of the resin were eluted with acetone and eluted with hexane to precipitate inorganic material and large polyester molecules. The eluate was evaporated. The remainder, dissolved in acetone, was separated into fractions on silica plates by thin layer chromatography (TLC). On the developed (hexane/chloroform, 15/85) plates, 20 bands were obtained under UV-light at 254 nm. Samples of the bands were scraped and used for patch testing. The scraping at a retention factor (Rf) of 0.24 caused a skin reaction. The bands at this retention were removed from six plates, combined, eluted with acetone and purified again by TLC. The purified fraction mixed in petrolatum in the dilution series was used for conclusive patch testing on the patient. An allergic reaction was induced at down to 0.003% wt/wt. According to MS and IR analyses, the isolated compound was diethyleneglycol maleate (DEGM, MW204). In addition to the resin part, the sanding dust also contained this monomer. 相似文献
82.
Alarmo EL Kuukasjärvi T Karhu R Kallioniemi A 《Breast cancer research and treatment》2007,103(2):239-246
Bone morphogenetic proteins (BMPs) regulate diverse cellular processes, such as proliferation, differentiation, and apoptosis.
The BMPs have been studied in several cancers, but thus far contradictory results have been obtained and, especially in breast
cancer, information on BMPs is still limited. We performed a systematic expression survey of BMPs and their receptors in breast
cancer. mRNA expression was studied of seven BMP ligands (BMP2-BMP8) and six receptors (ACVR1, BMPR1A, BMPR1B, BMPR2, ACVR2A, and ACVR2B) that specifically mediate BMP signals. Expression levels were determined in 22 breast cancer cell lines, 39 primary breast
tumors, normal human mammary epithelial cell line, and normal mammary gland using semiquantitative RT-PCR. The expression
frequencies and expression levels of different BMPs varied considerably in breast cancer with BMP4 and BMP7 being most frequently expressed and showing highest expression levels. The BMP specific receptors were more uniformly expressed
and indicated that breast cancer is fully capable of transmitting BMP signals. Expression frequencies and levels for both
the ligands and the receptors were in good concordance between the breast cancer cell lines and primary tumors. We can conclude
that breast cancers possess functional BMP signaling machinery on the cell surface with distinct differences in the expression
of various BMP ligands. Our survey focuses the attention particularly toward BMP4 and BMP7 and suggests their importance in breast cancer. Breast cancer cell lines and the data generated here serve as a good resource
for further studies on BMP function in breast cancer. 相似文献
83.
84.
Kylliki Tarvainen Riitta Jolanki Maj-Len Henriks Eckerman Tuula Estlander 《Contact dermatitis》1998,39(1):46-47
Formaldehyde is a ubiquitous and potent sensitizer. Formaldehyde-sensitive patients may have long-lasting hand eczema (1). Contact dermatitis from formaldehyde is often chronic, probably because it is so difficult to avoid exposure to formaldehyde-containing products. An investigation in Denmark showed that 1/3 of all cosmetic products contained formaldehyde or formaldehyde-releasing preservatives (2). Formaldehyde can also be found in many houshold products. In recent years, the use of moistened baby toilet tissues has greatly increased. 相似文献
85.
Maria Siponen Tomi Penna Meeri Apaja-Sarkkinen Riitta Palatsi Tuula Salo 《Journal of oral pathology & medicine》2006,35(4):252-253
Angiokeratoma is a rare, cutaneous vascular disorder that can occur in several clinically distinct conditions. It usually presents as multiple, red to blue or black, asymptomatic papules on the skin. Oral mucosal involvement is common in the systemic form, but very rare in the localized forms of angiokeratomas. We report the second case of a solitary papular angiokeratoma of the oral cavity. 相似文献
86.
Petri Aaltonen Johanna Rinta-Valkama Anu P?t?ri P?ivi Tossavainen Tuula Palmén Petri Kulmala Mikael Knip Harry Holth?fer 《Nephrology, dialysis, transplantation》2007,22(1):146-153
BACKGROUND: Patients with type 1 diabetes typically develop autoantibodies to antigens of the pancreatic islet cells including insulin, glutamic acid decarboxylase and the protein tyrosine phosphatase-related islet antigen 2 protein. Nephrin is a protein shared by the kidney glomeruli, pancreatic beta-cells and islet microendothelia. Since circulating antibodies to nephrin have been shown to cause proteinuria, we wanted to test whether such autoantibodies can be detected in diabetic patients. METHODS: We developed a radioimmunoprecipitation assay and analysed samples in a follow-up series of 66 patients with type 1 diabetes. RESULTS: A total of 24% of the patients tested positive for nephrin autoantibodies at diagnosis, whereas 23, 14 and 18% had these antibodies at 2, 5 and 10 years, respectively. During the follow-up at 16-19 years after diagnosis, 14 patients had signs of renal injury and 29% of them tested positive for nephrin autoantibodies in at least one sample. CONCLUSIONS: We conclude that a subset of patients with type 1 diabetes present with circulating autoantibodies to nephrin. However, the present data do not allow conclusions of a causative role for these antibodies in the pathogenesis of proteinuria in diabetes. 相似文献
87.
Tuula Koskinen Kimmo Sainio Juhani Rapola Helena Pihko Anders Paetau 《Muscle & nerve》1994,17(5):509-515
Infantile onset spinocerebellar ataxia with sensory neuropathy is a new, inherited multisystem disorder discovered in 19 Finnish patients. In order to define the neuropathy of the disease, we measured sensory nerve action potentials and nerve conduction velocities in 18 patients, and recorded somatosensory evoked potentials (SEP) in 10 patients and performed a sural nerve biopsy in 13 patients. The fixed and teased nerve fascicles were examined by light and electron microscopy, and the whole transverse section of a nerve fascicle was photographed and enlarged for morphometric measurements. Our investigation revealed an early onset, rapidly progressive axonal neuropathy: the sensory action potentials were decreased after the age of 2 and a severe loss of mainly large myelinated fibers was found. © 1994 John & Sons, Inc. 相似文献
88.
Androgen receptor amplification is associated with increased cell proliferation in prostate cancer 总被引:4,自引:0,他引:4
Haapala K Kuukasjärvi T Hyytinen E Rantala I Helin HJ Koivisto PA 《Human pathology》2007,38(3):474-478
Mechanisms of prostate cancer progression during hormonal therapy and the pathobiologic consequences of androgen receptor (AR) gene amplification are inadequately known. To further investigate the hypothesis that AR gene amplification is associated with increased cell proliferation, we analyzed 123 paraffin-embedded prostate cancer specimens from men who experienced tumor relapse during androgen withdrawal therapy. We used fluorescence in situ hybridization to quantify AR gene copy number and Ki-67 immunohistochemistry to determine cell proliferation. One third of the tumors showed AR gene amplification. Among tumors with AR amplification, the mean cell proliferation rate was 19.8 (SD, 12.3; 95% confidence interval [CI], 15.4-24.1), whereas it was 13.0 (SD, 15.9; 95% CI, 9.1-16.8) in tumors without amplification (P = .032). In the best fitting logistic regression model, only proliferation remained significant (P = .040). When the median Ki-67 labeling index (6.7%) of all tumors was used as a cutoff point, the tumors with AR amplification were more frequently highly proliferating than tumors with no amplification (P = .010; odds ratio, 3.4; 95% CI, 1.4-8.3). Our results imply that progression of prostate cancer during androgen withdrawal therapy is associated with AR gene amplification and increased cell proliferation rate in one third of tumors. We suggest that AR gene amplification is an important molecular mechanism underlying the increase in proliferation rate of a substantial fraction of recurrent prostate carcinomas. However, efforts should be targeted to develop prostate cancer cell lines to study causal relationships between AR gene amplification and various biologic variables. 相似文献
89.
Haverinen-Shaughnessy U Toivola M Alm S Putus T Nevalainen A 《Journal of exposure science & environmental epidemiology》2007,17(2):182-190
A total of 81 randomly selected elementary school teachers participated in two sampling campaigns conducted 2 weeks apart during the winter. A 24-h sample collection was performed using personal and microenvironmental sampling from homes, and an 8-h sample collection was performed from workplaces of the studied subjects. Filters were analyzed for particle mass, absorption coefficient of the filter, and for both total and viable microorganisms. Comprehensive questionnaire responses were collected from the teachers concerning weekly occurred symptoms during the previous 12-month period, and they filled in symptom diaries immediately after each sampling campaign concerning symptoms during the previous 24-h and 7-day periods. The effect of different recall periods on agreement between questionnaire responses was assessed. Factor analysis was used in order to identify factors explaining the pattern of correlations within the personal, home, and work measurements. Moreover, associations between personal, home, and work measurements of pollutants and symptoms were analyzed using general estimation equations. The recall period of 7 days seemed to provide the most reliable data for the health effect assessment. Information from the factor analysis may allow reduction of variables related to the exposure assessment, and better interpretation of results. Both personal exposure and concentrations of pollutants at home were more frequently associated with health symptoms than concentrations at work. In multipollutant analyses, absorbance coefficient was positively associated with eye symptoms, and total bacteria with both cough and blocked nose. 相似文献
90.
Rabeia Almahmoudi Abdelhakim Salem Elin Hadler-Olsen Gunbjørg Svineng Tuula Salo Ahmed Al-Samadi 《Cancer science》2021,112(6):2223-2232
Oral tongue squamous cell carcinoma (OTSCC) is one of the most common cancers worldwide and is characterized by early metastasis and poor prognosis. Recently, we reported that extracellular interleukin-17F (IL-17F) correlates with better disease-specific survival in OTSCC patients and has promising anticancer effects in vitro. Vasculogenic mimicry (VM) is the formation of an alternative vasculogenic system by aggressive tumor cells, which is implicated in treatment failure and poor survival of cancer patients. We sought to confirm the formation of VM in OTSCC and to investigate the effect of IL-17F on VM formation. Here, we showed that highly invasive OTSCC cells (HSC-3 and SAS) form tube-like VM on Matrigel similar to those formed by human umbilical vein endothelial cells. Interestingly, the less invasive cells (SCC-25) did not form any VM structures. Droplet-digital PCR, FACS, and immunofluorescence staining revealed the presence of CD31 mRNA and protein in OTSCC cells. Additionally, in a mouse orthotopic model, HSC-3 cells expressed VE-cadherin (CD144) but lacked Von Willebrand Factor. We identified different patterns of VM structures in patient samples and in an orthotopic OTSCC mouse model. Similar to the effect produced by the antiangiogenic drug sorafenib, IL-17F inhibited the formation of VM structures in vitro by HSC-3 and reduced almost all VM-related parameters. In conclusion, our findings indicate the presence of VM in OTSCC and the antitumorigenic effect of IL-17F through its effect on the VM. Therefore, targeting IL-17F or its regulatory pathways may lead to promising therapeutic strategies in patients with OTSCC. 相似文献