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991.
Egesten A Eliasson M Olin AI Erjefält JS Bjartell A Sangfelt P Carlson M 《International journal of colorectal disease》2007,22(12):1421-1427
Background Ulcerative colitis is characterized by relapsing mucosal inflammation where the lesions include tissue-damaging granulocytes.
In addition, T cells and natural killer (NK) cells play important pathophysiologic roles. Chemokines are a large family of
peptides that play key roles in the regulation of inflammation. The CXC-chemokines, growth-related oncogene (GRO)-α/CXCL1
and interleukin (IL)-8/CXCL8, both recruit neutrophils and possess mitogenic properties, whereas the interferon-dependent
CXC-chemokines monokine induced by gamma-interferon (MIG)/CXCL9, interferon-γ inducible protein of 10 kD/CXCL10, and IFN-inducible
T cell alpha chemoattractant/CXCL11 recruit and activate T cells and NK cells.
Materials and methods The expression of CXC-chemokines was studied in eight controls and in 11 patients suffering from ulcerative colitis in the
distal part of the colon, before and during topical treatment with corticosteroids. Perfusates (obtained before, after 7 days,
and after 28 days of treatment) and pinch biopsies (obtained before and after 28 days of treatment) were collected by colonoscopy.
The rectal release of GRO-α and MIG was determined by enzyme-linked immunosorbent assay (ELISA), and tissue expression of
the chemokines was detected in colonic tissue by immunohistochemistry.
Results In perfusates, high levels of GRO-α, IL-8, and MIG were detected compared with controls (p = 0.02, 0.005, and p = 0.03, respectively). During treatment with corticosteroids, both GRO-α and MIG decreased. In clinical nonresponders, characterized
by sustained inflammation, the levels of GRO-α and MIG remained elevated. Both epithelial cells and granulocytes, present
in the submucosa, expressed GRO-α and MIG as detected by immunohistochemistry.
Conclusions CXC-chemokines are likely to be important in the pathophysiology of ulcerative colitis and may become targets for novel treatment
strategies. In addition, GRO-α may serve as a marker of disease activity. 相似文献
992.
The aim of this study was to assess coping strategies of foreign-born men and women with type 2 diabetes in relation to demographic (sex, age, time in Sweden), medical, and socio-economic situation, and as compared with Swedish-born patients. Participants were foreign-born type 2 diabetic patients of European and non-European origin in primary health care in Stockholm County, comprising 41 men and 36 women aged 35-64 years, compared with Swedish-born type 2 diabetes patients, 121 men and 111 women. The General Coping Questionnaire, which measures five main orientations, dichotomised into "positive" and "negative" factors, i.e. 10 coping strategies, was used in the assessment. Medical and socio-economic data were obtained from medical records and postal questionnaires. Foreign-born men showed an impact on 6 of 10 coping strategies, and foreign-born women on 2 of 10 coping strategies, as compared to Swedish-born subjects. Longer time since migration and higher educational level were associated with lower scores for stressful coping strategies, while having financial problems and receiving a disability pension were associated with higher scores. In conclusion, the most stressful coping strategies were found among foreign-born men. It seems to be essential to improve and adjust diabetes care for immigrants, also including the psycho-social perspective. 相似文献
993.
Schueller PO Meyer C Brehm M Wernet P Schannwell CM Strauer BE 《International journal of cardiology》2007,118(3):398-399
Antegrade femoral artery access is commonly used for percutaneous transluminal revascularization of ipsilateral lower limbs in patients with critical limb ischemia. While hemostasis at the end of the procedure can be achieved by manual compression, this may lead to an increase in local vascular complications. Femoral artery closure devices, such as the Angioseal collagen plug and anchor device, have been approved and shown of benefit after retrograde femoral artery catheterization. To date, there are however no data on the use of such arteriotomy closure device after antegrade femoral access. We hereby report a case series of five patients in whom Angioseal was successfully used after antegrade femoral puncture and below-the-knee percutaneous transluminal angioplasty. In all cases the device enabled immediate and complete hemostasis without major complications, despite the intense antithrombotic regimen, including heparin, aspirin, and clopidogrel in all patients, as well as glycoprotein IIb/IIIa inhibitors (in two patients) and fibrinolytic therapy (in one). 相似文献
994.
Solomon A Richey T Murphy CL Weiss DT Wall JS Westermark GT Westermark P 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(26):10998-11001
The human cerebral and systemic amyloidoses and prion-associated spongiform encephalopathies are acquired or inherited protein folding disorders in which normally soluble proteins or peptides are converted into fibrillar aggregates. This is a nucleation-dependent process that can be initiated or accelerated by fibril seeds formed from homologous or heterologous amyloidogenic precursors that serve as an amyloid enhancing factor (AEF) and has pathogenic significance in that disease may be transmitted by oral ingestion or parenteral administration of these conformationally altered components. Except for infected brain tissue, specific dietary sources of AEF have not been identified. Here we report that commercially available duck- or goose-derived foie gras contains birefringent congophilic fibrillar material composed of serum amyloid A-related protein that acted as a potent AEF in a transgenic murine model of secondary (amyloid A protein) amyloidosis. When such mice were injected with or fed amyloid extracted from foie gras, the animals developed extensive systemic pathological deposits. These experimental data provide evidence that an amyloid-containing food product hastened the development of amyloid protein A amyloidosis in a susceptible population. On this basis, we posit that this and perhaps other forms of amyloidosis may be transmissible, akin to the infectious nature of prion-related illnesses. 相似文献
995.
Hvas CL Kelsen J Agnholt J Höllsberg P Tvede M Møller JK Dahlerup JF 《Scandinavian journal of gastroenterology》2007,42(5):592-601
OBJECTIVE: Crohn's disease (CD) has been associated with low mucosal interleukin (IL)-10 production, but the mechanism behind this deficiency remains unclear. The aim of this study was to investigate IL-10 and interferon (IFN)-gamma production in intestinal CD4+ T cells from CD patients and healthy volunteers (HV) and to examine how this was affected by bacterial products and the presence or absence of autologous dendritic cells. MATERIAL AND METHODS: We cultured intestinal CD4+ T cells from CD patients (n=9) and HV (n=6) and differentiated dendritic cells from their peripheral monocytes. Intestinal T cells were stimulated with Lactobacillus strains or autologous intestinal bacteria in the presence or absence of dendritic cells. IL-10 and IFN-gamma were measured on day 4. RESULTS: When there were autologous dendritic cells present, CD intestinal T cells produced high levels of IFN-gamma (mean 6.4 ng/ml+/-standard error of the mean 1.1 ng/ml) but low levels of IL-10 (0.7 ng/ml+/-0.1 ng/ml). In contrast, HV intestinal T cells produced less IFN-gamma (3.9 ng/ml+/-0.8 ng/ml, p=0.06) and more IL-10 (4.6 ng/ml+/-0.9 ng/ml, p=0.0001) than CD intestinal T cells. Co-culture with Lactobacilli failed to revert this imbalance in CD, but tended to do so in HV. When there were no dendritic cells, CD intestinal T cells responded to autologous bacteria with an increased IFN-gamma production (2.3+/-1.3 ng/ml) compared with HV intestinal T cells (0.3+/-0.2 ng/ml). CONCLUSIONS: Crohn's disease intestinal CD4+ T cells display a pro-inflammatory cytokine profile with impaired production of the regulatory cytokine IL-10. Tolerogenic bacteria (Lactobacilli) failed to restore this regulatory defect. 相似文献
996.
Poor prognosis in carcinoma is associated with a gene expression signature of aberrant PTEN tumor suppressor pathway activity 总被引:7,自引:0,他引:7
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Saal LH Johansson P Holm K Gruvberger-Saal SK She QB Maurer M Koujak S Ferrando AA Malmström P Memeo L Isola J Bendahl PO Rosen N Hibshoosh H Ringnér M Borg A Parsons R 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(18):7564-7569
Pathway-specific therapy is the future of cancer management. The oncogenic phosphatidylinositol 3-kinase (PI3K) pathway is frequently activated in solid tumors; however, currently, no reliable test for PI3K pathway activation exists for human tumors. Taking advantage of the observation that loss of PTEN, the negative regulator of PI3K, results in robust activation of this pathway, we developed and validated a microarray gene expression signature for immunohistochemistry (IHC)-detectable PTEN loss in breast cancer (BC). The most significant signature gene was PTEN itself, indicating that PTEN mRNA levels are the primary determinant of PTEN protein levels in BC. Some PTEN IHC-positive BCs exhibited the signature of PTEN loss, which was associated to moderately reduced PTEN mRNA levels cooperating with specific types of PIK3CA mutations and/or amplification of HER2. This demonstrates that the signature is more sensitive than PTEN IHC for identifying tumors with pathway activation. In independent data sets of breast, prostate, and bladder carcinoma, prediction of pathway activity by the signature correlated significantly to poor patient outcome. Stathmin, encoded by the signature gene STMN1, was an accurate IHC marker of the signature and had prognostic significance in BC. Stathmin was also pathway-pharmacodynamic in vitro and in vivo. Thus, the signature or its components such as stathmin may be clinically useful tests for stratification of patients for anti-PI3K pathway therapy and monitoring therapeutic efficacy. This study indicates that aberrant PI3K pathway signaling is strongly associated with metastasis and poor survival across carcinoma types, highlighting the enormous potential impact on patient survival that pathway inhibition could achieve. 相似文献
997.
Monitoring of lipid storage in Caenorhabditis elegans using coherent anti-Stokes Raman scattering (CARS) microscopy 总被引:1,自引:0,他引:1
Hellerer T Axäng C Brackmann C Hillertz P Pilon M Enejder A 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(37):14658-14663
Better understanding of the fundamental mechanisms behind metabolic diseases requires methods to monitor lipid stores on single-cell level in vivo. We have used Caenorhabditis elegans as a model organism to demonstrate the limitations of fluorescence microscopy for imaging of lipids compared with coherent anti-Stokes Raman scattering (CARS) microscopy, the latter allowing chemically specific and label-free imaging in living organisms. CARS microscopy was used to quantitatively monitor the impact of genetic variations in metabolic pathways on lipid storage in 60 specimens of C. elegans. We found that the feeding-defective mutant pha-3 contained a lipid volume fraction one-third of that found in control worms. In contrast, mutants (daf-2, daf-4 dauer) with deficiencies in the insulin and transforming growth factors (IGF and TGF-beta) signaling pathways had lipid volume fractions that were 1.4 and 2 times larger than controls, respectively. This was observed as an accumulation of small-sized lipid droplets in the hypodermal cells, hosting as much as 40% of the total lipid volume in contrast to the 9% for the wild-type larvae. Spectral CARS microscopy measurements indicated that this is accompanied by a shift in the ordering of the lipids from gel to liquid phase. We conclude that the degree of hypodermal lipid storage and the lipid phase can be used as a marker of lipid metabolism shift. This study shows that CARS microscopy has the potential to become a sensitive and important tool for studies of lipid storage mechanisms, improving our understanding of phenomena underlying metabolic disorders. 相似文献
998.
Roos C Lidfeldt J Agardh CD Nyberg P Nerbrand C Samsioe G Westrin A 《Metabolism: clinical and experimental》2007,56(6):825-829
Previous studies have suggested that depression increases the risk for diabetes and that this may be mediated through insulin resistance. The study aimed to analyze if self-rated symptoms of depression are related to insulin resistance among middle-aged and older Swedish women with features of the metabolic syndrome and being at risk for type 2 diabetes mellitus. We analyzed data from 1047 Swedish women aged 50 to 64 years without a history of diabetes and living in the southern part of Sweden. A variable self-rated symptoms of depression (SRSD) was defined by using the Gothenburg Quality of Life instrument. We estimated odds ratios (ORs) to determine whether or not SRSD was associated with the homeostasis model assessment of insulin resistance. The variable SRSD was not associated with insulin resistance. However, it was positively associated with waist-hip ratio (OR, 1.95; 95% confidence interval, 1.28-3.00) and negatively associated with physical exercise (OR, 1.29; 95% confidence interval, 0.99-1.68) after multivariate adjustment. In conclusion, lifestyle factors such as physical inactivity and abdominal obesity, but not insulin resistance, seem to be related to self-rated symptoms of depression in women with risk factors for diabetes mellitus. The relationship between insulin resistance and major depression needs to be further examined. 相似文献
999.
Gianni S Geierhaas CD Calosci N Jemth P Vuister GW Travaglini-Allocatelli C Vendruscolo M Brunori M 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(1):128-133
A unifying view has been recently proposed according to which the classical diffusion-collision and nucleation-condensation models may represent two extreme manifestations of an underlying common mechanism for the folding of small globular proteins. We report here the characterization of the folding process of the PDZ domain, a protein that recapitulates the three canonical steps involved in this unifying mechanism, namely: (i) the early formation of a weak nucleus that determines the native-like topology of a large portion of the structure, (ii) a global collapse of the entire polypeptide chain, and (iii) the consolidation of the remaining partially structured regions to achieve the native state conformation. These steps, which are clearly detectable in the PDZ domain investigated here, may be difficult to distinguish experimentally in other proteins, which would thus appear to follow one of the two limiting mechanisms. The analysis of the (un)folding kinetics for other three-state proteins (when available) appears consistent with the predictions ensuing from this unifying mechanism, thus providing a powerful validation of its general nature. 相似文献
1000.
Bang LE Wiinberg N Wachtell K Larsen J Olsen MH Tuxen C Hildebrandt PR Ibsen H 《Blood pressure》2007,16(6):392-397
Objective. The Losartan Intervention For Endpoint reduction in hypertension (LIFE) study showed that losartan-based treatment reduced risk of the composite endpoint of cardiovascular death, stroke and myocardial infarction compared with atenolol-based treatment in patients with hypertension and left ventricular hypertrophy with similar office blood pressure (BP) reduction. Our aim was to investigate the effect of losartan- and atenolol-based treatment on 24-h ambulatory BP and heart rate (HR) in LIFE. Methods: In 110 patients, 24-h ambulatory BP and heart rate were recorded at baseline and 1 year after randomization. Results: Ambulatory BP was comparably reduced throughout the 24-h period after 1 year of losartan- vs atenolol-based antihypertensive treatment. Office and ambulatory BP were comparably reduced in the follow-up period. Early morning surge in BP was similar between groups. Non-dipping status was more frequent in the losartan group (p = 0.01). From baseline to Year 1 the 24-h HR profile for the losartan group was unchanged, but, as expected, there was a significant decrease in daytime HR in the atenolol group, which was not as large during early night-time. Conclusion: There were no differences in 24-h BP burden and HR that could explain the difference in outcome in favor of losartan vs atenolol in the LIFE study. 相似文献