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21.
Expression of syndecan-1, a cell surface proteoglycan that binds growth factors and extracellular matrix components, was studied in normal and pathological human uterine cervix using immunohistochemical methods. Normal cervical squamous epithelium showed positive staining for syndecan-1 in all cell layers, except the basal cell layer, whereas endocervical columnar epithelium stained weakly. In non-neoplastic reactive lesions, metaplastic squamous cells were positive for syndecan-1, whereas columnar cells showed weak or negative staining. In cervical condylomas, cells showing koilocytotic atypia were positive for syndecan-1. The progression of cervical intraepithelial neoplasia (CIN) grade I to grade III was associated with reduced syndecan-1 expression and localization of syndecan-1 to more superficial cell layers. In squamous cell carcinomas (SCCs), syndecan-1 expression correlated with histological differentiation, being absent from most poorly differentiated tumours. The results suggest that loss of syndecan-1 from atypical cells is an early event during cervical carcinogenesis and show a close association of syndecan-1 expression with preserved epithelial morphology and differentiation. 相似文献
22.
Apolipoprotein B gene DNA polymorphisms are associated with macro- and microangiopathy in non-insulin-dependent diabetes mellitus 总被引:2,自引:0,他引:2
Olavi Ukkola Markku J. Savolainen Pasi I. Salmela Kai von Dickhoff Y. Antero Kesäniemi 《Clinical genetics》1993,44(4):177-184
Ukkola O, Savolainen MJ, Salmela PI, von Dickhoff K, Kesäniemi YA. Apolipoprotein B gene DNA polymorphisms are associated with macro-and microangiopathy in non-insulin-dependent diabetes mellitus. Clin Genet 1993: 44: 177–184. © Munksgaard, 1993 The relationship between diabetic macroangiopathy or microangiopathy and apolipoprotein B (apoB) polymorphism was studied in 139 male and 129 female patients with non-insulin-dependent diabetes (NIDDM) mellitus, comprising consecutive patients with poor diabetic control (HBA1 13.2%\pm2.7 (SD)) referred to our hospital. Plasma cholesterol and triglyceride concentrations were higher in the patients who were homozygous for the X2 allele (presence of Xba I cleavage site). Patients with the X1 allele (absence of Xba I cleavage site) tended to have a higher frequency of macroangiopathy, although the differences were not statistically significant. There was no difference in the prevalence of microangiopathy between the groups. In subjects with only an R1 allele (= R +; homozygous for the presence of EcoR I cleavage site) the prevalence of coronary heart disease (CHD) was observed to be high (61.9%) as compared to the subjects possessing an R2 allele (= R —; homozygous or heterozygous for the absence of the EcoR I cleavage site) (46.7%; p<0.02). When the polymorphisms Xba I (subjects homozygous for the absence of the cutting site = X +; subjects homozygous or heterozygous for the presence of the cutting site = X —) and EcoR I were combined, the prevalence of macroangiopathy was observed to be high in X + R + (80.0%) as compared with X + R- (44.2%), X-R+ (56.8%) and X-R- (50.0%) (p<0.03). The prevalence of macroangiopathy tended to be particularly high in patients with the apoprotein E4 allele (phenotype E4\4 or E4/3), combined with either X+ or R +. Our findings suggest that variation at the apoB locus is one of the factors involved in predisposing diabetic patients to the development of arterial disease. As in previous studies the effect of the variation at the apoB gene on circulating lipid levels was observed. The data also support a role for the e4 allele of the apolipoprotein E gene as an important determinant of macroangiopathy in NIDDM. 相似文献
23.
Kontiokari T Renko M Kaijalainen T Kuisma L Leinonen M 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2000,108(11):734-738
It is not known how well nasopharyngeal swab culture represents pneumococcal carriage status. We tested this by comparing swab culture to quantitative culture and quantitative PCR of mucosal tissue in a rat model of pneumococcal carriage. Quantitative culture and quantitative PCR identified significantly more carriers compared to swab culture (differences 15% and 33%, 95% CI 1-28% and 16-47%, p=0.04 and 0.001, respectively). The sensitivity and specificity of swab culture was 75/92% and 63/100% compared to quantitative tissue culture and quantitative PCR, respectively. The quantitative estimates of culture and PCR were very similar (Pearson correlation coefficient 0.79, p<0.001). In conclusion, even a well-controlled swab sampling markedly underestimates pneumococcal carriage rate, and simultaneous use of quantitative culture and PCR increases the number of positive samples by about one third. 相似文献
24.
Antti Hervonen Ilona Linnoila Virginia M. Pickel Pauli Helén Markku Pelto-Huikko Hannu Alho Richard J. Miller 《Neuroscience》1981,6(3):323-330
Both [Leu5]- and [Met5]-enkephalin have been localized immunohistochemically in nerve fibres and in small, intensely fluorescent cells of adult human sympathetic ganglia. The nerve fibres showing enkephalin-like immunoreactivity formed a network varying in density around the sympathetic neurons, some being closely related to the perikarya. No labelled neuronal cell bodies were found. No structures within the ganglion were labelled after reaction with antibodies to vasoactive intestinal polypeptide, adrenocorticotrophin or substance P. No differences between the distributions of [Leu5]-and [Met5]-enkephalin-like immunoreactivities were found.The physiological roles of enkephalins are still unknown, but it is possible that they might act as neurotransmitters or neuromodulators in the human sympathetic nervous system. 相似文献
25.
Nevas M Lindström M Virtanen A Hielm S Kuusi M Arnon SS Vuori E Korkeala H 《Journal of clinical microbiology》2005,43(1):511-513
Clostridium botulinum type B was detected by multiplex PCR in the intestinal contents of a suddenly deceased 11-week-old infant and in vacuum cleaner dust from the patient's household. C. botulinum was also isolated from the deceased infant's intestinal contents and from the household dust. The genetic similarity of the two isolates was demonstrated by pulsed-field gel electrophoresis and randomly amplified polymorphic DNA analysis, thereby confirming that dust may act as a vehicle for infant botulism that results in sudden death. 相似文献
26.
27.
Galina Sanaksenaho Annika Mutanen Nimish Godbole Maria Hukkinen Laura Merras-Salmio Reetta Kivisaari Antti Kyrönlahti Marjut Pihlajoki Jouko Lohi Markku Heikinheimo Mikko P Pakarinen 《Journal of pediatric surgery》2021,56(5):966-974
BackgroundIntestinal adaptation has been extensively studied experimentally, but very limited data is available on human subjects. In this study we assessed intestinal adaption in humans with short bowel syndrome (SBS).MethodsWe comparatively evaluated mucosal hyperplasia, inflammation, barrier function and nutrient transport using histology, immunohistochemistry and qPCR for selected 52 key genes in duodenal biopsies obtained from children with SBS after weaning off parenteral nutrition (n = 33), and matched controls without intestinal pathology (n = 12). Small bowel dilatation was assessed from contrast small bowel series.ResultsDuodenal mucosa of SBS children showed increased histologic inflammation of lamina propria (p = 0.033) and mucosal mRNA expression of tumor necrosis factor (p = 0.027), transforming growth factor (TGF)-β2 (p = 0.006) and caveolin-1 (CAV1; p = 0.001). Villus height, crypt depth, enterocyte proliferation, apoptosis and expression of proliferation and nutrient transport genes remained unchanged. Pathologic small bowel dilatation reduced crypt depth (p = 0.045) and downregulated mRNA expression of interleukin (IL)-6 by three-fold (p = 0.008), while correlating negatively with IL6 (r = -0.609, p = 0.004). Loss of ileocecal valve (ICV) upregulated mRNA expression of toll-like receptor 4 (TLR4), TGF-β1, CAV1, several apoptosis regulating genes, and mRNA expression of zonulin (p < 0.05 for all).ConclusionsDespite successful adaptation to enteral autonomy, duodenal mucosa of SBS children displayed histologic and molecular signs of abnormal inflammation and regulation of epithelial permeability, whereas no structural or molecular signs of adaptive hyperplasia or enhanced nutrient transport were observed. Excessive dilatation of the remaining small bowel paralleled impaired duodenal crypt homeostasis, while absence of ICV modified regulation of mucosal inflammation, regeneration and permeability.Level of evidenceII 相似文献
28.
The initial mechanical strength and strength retention in vitro and in vivo of novel absorbable and self-reinforced polyglycolide (SR-PGA) screws for the fixation of fractures and osteotomies were determined. The SR-PGA screws showed initial bending strength values comparable with those of yield strength of standard stainless steel. The SR-PGA screws lost all their bending and shear strengths in 6 weeks in vivo. The strength retention properties of SR-PGA screws are sufficient for safe fixation of relatively rapidly consolidating fractures and osteotomies of cancellous bone that are not exposed to hard mechanical stresses. 相似文献
29.
Markku Walamies Matti Koskinen Arto Uusitalo Kari Niemelä 《The International Journal of Cardiac Imaging》1994,10(2):123-129
Myocardial metabolism in exercise was determined by studying 21 syndromeX patients and 14 healthy volunteers with an aromatic fatty acid analogue IPPA and a gamma camera. We developed criteria for visual semiquantitative assessment of relative segmental radiotracer uptake and washout, and tested a new computer program for quantitative evaluation. One volunteer (7%) and 12 patients (57%) showed visually inhomogeneous uptake (p=0.006, 2-test) in SPECT polar tomograms after a maximal ergometry test. Images in none of the volunteers and seven patients (33%) gave the impression of a slowed regional washout (p=0.057). Only six patients (29%) had a normal radial polarogram. Patients with irregular coronary angiograms (showing slow flow or minor sclerosis) and those with chest pain during the IPPA exercise test had a very low frequency of normalcy, but this was not significant.Total washout was higher in patients than in the reference population, as the exercise to rest activity ratio was 1.36 SD 0.13 versus 1.25 SD 0.11 in computerized quantitation (p=0.015, t-test). Washout did not correlate with age, sex or exercise heart rate. Regarding computerized analysis of uptake and slow washout, the number of deviant segments was not significantly higher in patients than in reference population. Semiquantitative and quantitative analysis correlated in the assessment of uptake, but not in the assessment of washout. Possible reasons for the discrepancy are discussed.Conclusions of this study are not straightforward. SyndromeX was associated with inhomogeneous IPPA uptake, which is not at variance with the theory of microvascular dysfunction. On the other hand, the analysis of washout presumably implies higher fatty acid utilization in patients than in normal controls, which is not a characteristic phenomenon in myocardial ischemia. 相似文献
30.
The anxiolytic profile of dexmedetomidine, a novel, highly-selective 2-adrenergic agonist, was examined in rats in the elevated plus-maze test when administered either alone or in combination with the benzodiazepine agonist midazolam. Dexmedetomidine, 0.1–10 µg/kg, was inactive in modifying the rats' behavioral response in this test. Midazolam, 0.1–10 mg/kg, dose-dependently produced an anxiolytic-like profile characterized by an increased time spent in the open arms of the elevated plus-maze. A combination of dexmedetomidine 0.5 µg/kg and midazolam 0.5 mg/kg produced a synergistic interaction. This heterergic interaction of dexmedetomidine on midazolam's anxiolytic-like profile was dose-dependently blocked by pretreatment with an 2-adrenergic antagonist, atipamezole, 10–50 µg/kg, and a benzodiazepine antagonist flumazenil, 1.0 and 10 mg/kg, but not by the 1-adrenergic antagonist, prazosin, 0.1–10 mg/kg. While the transmembrane signal transduction pathways for benzodiazepine- and 2-agonist responses do not share any molecular component, there does appear to be crosstalk between these two systems. These may involve GABA or noradrenergic downstream effects of either dexmedetomidine or midazolam, respectively. 相似文献