Microdensitometry of osteopontin as an immunohistochemical prognostic biomarker in colorectal carcinoma tissue microarrays: potential and limitations of the method in ‘biomarker pathology’

Prall F, Maletzki C & Linnebacher M
(2012) Histopathology  61, 823–832 Microdensitometry of osteopontin as an immunohistochemical prognostic biomarker in colorectal carcinoma tissue microarrays: potential and limitations of the method in ‘biomarker pathology’ Aims: To explore the potential and limitations of ‘biomarker pathology’ with quantitative immunohistochemistry on tissue microarrays, taking osteopontin and colorectal carcinoma as a model system. Methods and results: Microdensitometry for quantitative evaluation of osteopontin immunohistochemistry (clone OP3N) on digital microphotographs using the public domain software ImageJ was observed to be straightforward to perform and reliable. However, using colorectal carcinoma cell lines (n = 11) the correlation between densitometric evaluations of Western blots and microdensitometry of immunocytochemistry of slide cultures was only moderate. A virtual resampling method to simulate tissue microarrays showed that, due to heterogeneity of immunostaining, tumours were misclassified in nearly 20% of the arrays, even if four punches were used. With regard to prognosis, microdensitometric evaluation of a tissue microarray made of a clinicopathologically well‐characterized series of colorectal carcinomas with long‐term follow‐up (222 cases evaluable in the tissue microarray, UICC Stages I–III/R0) showed a moderate survival advantage of patients with high osteopontin expression by microdensitometry. Conclusions: These results challenge the basic assumption that microdensitometry is a precise technique for the quantification of proteins detected by immunohistochemistry and delineate drawbacks encountered when working with tissue microarrays in clinicopathological studies.     

Effect of fluvastatin slow-release on low density lipoprotein (LDL) subfractions in patients with type 2 diabetes mellitus: baseline LDL profile determines specific mode of action

The objective of this study was to determine the effect of slow-release (XL) fluvastatin on low density lipoprotein (LDL) subfractions in type 2 diabetes. A multicenter, double-blind, randomized, parallel-group comparison of fluvastatin XL 80 mg (n = 42) and placebo (n = 47), each given once-daily for 8 wk, in 89 patients with type 2 diabetes (HbA1c: 7.2 +/- 1.0%, LDL cholesterol (LDL-C): 3.4 +/- 0.7 mmol/liter, high density lipoprotein cholesterol: 1.1 +/- 0.3 mmol/liter, and triglycerides (TG): 2.4 +/- 1.4 mmol/liter). At baseline and on treatment, plasma lipoproteins were isolated and quantified. Eight weeks of fluvastatin treatment decreased total cholesterol (-23.0%, P < 0.001), LDL-C (-29%, P < 0.001) and TG (-18%, P < 0.001), compared with placebo. At baseline, there was a preponderance of dense LDL (dLDL) (apolipoprotein B in LDL-5 plus LDL-6 > 25 mg/dl) in 79% of patients, among whom fluvastatin decreased all LDL subfractions, reductions in dLDL being greatest (-28%, P = 0.001; cholesterol in dLDL -29%). In patients with low baseline dLDL (apolipoprotein B in LDL-5 plus LDL-6 相似文献   

Alanine Aminotransferase Elevation in Obese Infants and Children: A Marker of Early Onset Non Alcoholic Fatty Liver Disease

Background:

Elevated aminotransferases serve as surrogate markers of non-alcoholic fatty liver disease, a feature commonly associated with the metabolic syndrome. Studies on the prevalence of fatty liver disease in obese children comprise small patient samples or focus on those patients with liver enzyme elevation.

Objectives:

We have prospectively analyzed liver enzymes in all overweight and obese children coming to our tertiary care centre.

Patients and Methods:

In a prospective study 224 healthy, overweight or obese children aged 1 - 12 years were examined. Body Mass Index-Standard Deviation Score, alanine aminotransferase, aspartate aminotransferase and gamma-glutamyl-transpeptidase were measured.

Results:

Elevated alanine aminotransferase was observed in 29% of children. 26 % of obese and 30 % of overweight children had liver enzyme elevations. Obese children had significantly higher alanine aminotransferase levels than overweight children (0.9 vs. 0.7 times the Upper Limit of Normal; P = 0.04).

Conclusions:

Elevation of liver enzymes appears in 29 % obese children in a tertiary care centre. Absolute alanine aminotransferase levels are significantly higher in obese than in overweight children. Even obese children with normal liver enzymes show signs of fatty liver disease as demonstrated by liver enzymes at the upper limit of normal.     

Identification and characterization of the tungsten-containing class of benzoyl-coenzyme A reductases

Aromatic compounds are widely distributed in nature and can only be biomineralized by microorganisms. In anaerobic bacteria, benzoyl-CoA (BCoA) is a central intermediate of aromatic degradation, and serves as substrate for dearomatizing BCoA reductases (BCRs). In facultative anaerobes, the mechanistically difficult reduction of BCoA to cyclohexa-1,5-dienoyl-1-carboxyl-CoA (dienoyl-CoA) is driven by a stoichiometric ATP hydrolysis, catalyzed by a soluble, three [4Fe-4S] cluster-containing BCR. In this work, an in vitro assay for BCR from the obligately anaerobic Geobacter metallireducens was established. It followed the reverse reaction, the formation of BCoA from dienoyl-CoA in the presence of various electron acceptors. The benzoate-induced activity was highly specific for dienoyl-CoA (K_m = 24 ± 4 μM). The corresponding oxygen-sensitive enzyme was purified by several chromatographic steps with a 115-fold enrichment and a yield of 18%. The 185-kDa enzyme comprised 73- and 20-kDa subunits, suggesting an α₂β₂-composition. MS analysis revealed the subunits as products of the benzoate-induced bamBC genes. The αβ unit contained 0.9 W, 15 Fe, and 12.5 acid-labile sulfur. Results from EPR spectroscopy suggest the presence of one [3Fe-4S]^0/+1 and three [4Fe-4S]^+1/+2 clusters per αβ unit; oxidized BamBC exhibited an EPR signal typical for a W(V) species. The FeS clusters and the W- cofactor could only be fully reduced by dienoyl-CoA. BamBC represents the prototype of a previously undescribed class of dearomatizing BCRs that differ completely from the ATP-dependent enzymes from facultative anaerobes.     

Gastrointestinal failure in intensive care: a retrospective clinical study in three different intensive care units in Germany and Estonia

Background  

While gastrointestinal problems are common in ICU patients with multiple organ failure, gastrointestinal failure has not been given the consideration other organ systems receive. The aim of this study was to evaluate the incidence of gastrointestinal failure (GIF), to identify its risk factors, and to determine its association with ICU mortality.     

CD34-/CD133+/VEGFR-2+ endothelial progenitor cell subpopulation with potent vasoregenerative capacities

Our goal was to identify functionally important subpopulations within the heterogenous group of endothelial progenitor cells (EPC). Fluorescence-activated cell sorter analysis of CD133+ progenitor cells revealed the presence of CD34+ and CD34- subpopulations. CD34-/133+ progenitors differentiate into CD34+/133+ EPC, adhere more potently than these in response to SDF-1, and rapidly home to sites of limb ischemia in human volunteers. In human coronary atherectomy samples, fewer CD34-/133+ than CD34+/133+ EPC are present in stable plaques, whereas cell numbers increase with a reversion of the ratio in unstable lesions. In CD34-/133+ EPC-injected nude mice, more transplanted cells coexpressing endothelial markers home to carotid artery lesion endothelium than in CD34+/133+-injected mice. In the former, lesions were smaller and reendothelialization higher than in the latter. We identified a new CD34-/133+ EPC subpopulation, which is apparently a precursor of "classical" CD34+/133+ EPC, and functionally more potent than these with respect to homing and vascular repair.     

Angiotensin II inhibition reduces stress sensitivity of hypothalamo-pituitary-adrenal axis in spontaneously hypertensive rats

Angiotensin II type 1 (AT(1)) receptors are expressed within organs of the hypothalamo-pituitary-adrenal (HPA) axis and seem to be important for its stress responsiveness. Secretion of CRH, ACTH, and corticosterone (CORT) is increased by stimulation of AT(1) receptors. In the present study, we tested whether a blockade of the angiotensin II system attenuates the HPA axis reactivity in spontaneously hypertensive rats. Spontaneously hypertensive rats were treated with candesartan (2 mg/kg), ramipril (1 mg/kg), or mibefradil (12 mg/kg) for 5 wk. In addition to baseline levels, CORT and ACTH responses to injection of CRH (100 microg/kg) were monitored over 4 h. mRNA of CRH, proopiomelanocortin, AT(1A), AT(1B), and AT(2) receptors was quantified by real-time PCR. All treatments induced equivalent reductions of blood pressure and had no effect on baseline levels of CORT and ACTH. However, both candesartan and ramipril significantly reduced CRH-stimulated plasma levels of ACTH (-26 and -15%) and CORT (-36 and -18%) and lowered hypothalamic CRH mRNA (-25 and -29%). Mibefradil did not affect any of these parameters. Gene expression of AT(1A), AT(1B), and AT(2) receptors within the HPA axis was not altered by any drug. We show for the first time that antihypertensive treatment by inhibition of AT(1) receptors or angiotensin-converting enzyme attenuates HPA axis reactivity independently of blood pressure reduction. This action is solely evident after CRH stimulation but not under baseline conditions. Both a reduced pituitary sensitivity to CRH and a down-regulation of hypothalamic CRH expression have the potential to reduce HPA axis activity during chronic AT(1) blockade or angiotensin-converting enzyme inhibition.     

Das Sterbehilfegesetz verunsichert

Pflegezeitschrift - Im Dezember 2015 wurde das „Gesetz zur Strafbarkeit der geschäftsmäßigen Förderung der Selbsttötung“ beschlossen. Leider verunklart es die...     

Serological and DNA-based evaluation of Chlamydia pneumoniae infection in inflammatory bowel disease

OBJECTIVES: Chlamydia has been associated with autoimmune diseases, but a link between chlamydial infection and the aetiopathogenesis of inflammatory bowel disease (IBD) remains controversial. In this study we assessed the relationship between chlamydial infection and IBD, as evidenced by serological measurement and DNA analysis of mucosal biopsy specimens. PATIENTS AND METHODS: The sera of 78 patients with Crohn's disease (CD), 24 patients with ulcerative colitis (UC), 73 healthy family members, and 20 healthy controls were tested for anti-C. pneumoniae IgG titres. A subgroup consisting of 13 UC and 39 CD patients was screened for the presence of chlamydial DNA on 42 inflamed versus 30 non-inflamed biopsy specimens and for mutations of their NOD2/CARD15 gene. RESULTS: Anti-C. pneumoniae IgG antibodies were found in the sera of 32 (41%) patients with CD, 11 (46%) patients with UC, 35 (48%) of unaffected family members, and nine (45%) unrelated healthy controls. Thirty-five percent of the control, 18% CD and 24% UC biopsy specimens contained C. pneumoniae DNA. In CD, however, C. pneumoniae DNA was significantly more frequently found in inflamed (27%) versus non-inflamed (8%) biopsy specimens (P < 0.05, Fisher's exact test). The frequencies of NOD2/CARD15 mutations were 33% for CD patients with C. pneumoniae DNA compared to 47% for CD patients without C. pneumoniae DNA. CONCLUSION: We found no marked differences in respect to anti-C. pneumoniae serum IgG or C. pneumoniae DNA between healthy controls and patients with IBD. However, in CD patients, inflamed tissue specimens contained significantly more likely C. pneumoniae DNA compared with biopsies from unaffected areas. Thus C. pneumoniae is unlikely to be of pathogenic importance in IBD while it may still influence local clinical manifestations.