First evidence for digenic inheritance in hereditary colorectal cancer by mutations in the base excision repair genes

Biallelic mutations in the base excision repair gene Mut Y homologue (MUTYH) are responsible for variable recessively inherited phenotypes of polyposis. Beside MUTYH, the proteins 8-oxo-guanine DNA glycosylase (OGG1) and MTH1 (or NUDT1) are also involved in the repair of 7,8-dihydro-8-oxoguanine (8-oxo-G), previous studies, however, only found missense mutations of unclear pathogenicity in either MTH1 or OGG1. To investigate the role of a defective 8-oxo-G repair we performed a germline mutation screening in the genes OGG1, MTH1 and MUTYH, in 81 patients with a clinical phenotype ranging from attenuated or atypical adenomatous polyposis coli including hyperplastic polyps to hereditary non-polyposis colorectal cancer (HNPCC) type X syndrome without mono- or biallelic mutations in either APC, MUTYH or the DNA mismatch repair genes.We describe here the first pathogenic germline mutation in OGG1, a splice site mutation affecting exon 1, which was inherited from the father, in combination with a maternal MUTYH missense mutation p.Ile223Val in a female patient with advanced synchronous colon cancer and adenomas at the age of 36 years pointing towards digenic inheritance for colorectal cancer (CRC) predisposition.Monoallelic missense mutations in MTH1 (3x), OGG1 (2x), or MUTYH (3x) were identified in 10 patients (12%), three of them were novel.Our findings indicate that mutations in other genes of the 8-oxo-G repair beside MUTYH are involved in CRC predisposition. Oligogenic inheritance affecting genes of a certain repair pathway might therefore be the missing link between monogenic and polygenic traits.     

Low number of regulatory T cells in skin lesions of patients with cutaneous lupus erythematosus

OBJECTIVE: To define the phenotype and function of CD4+,CD25+ regulatory T cells (Treg) in patients with cutaneous lupus erythematosus (CLE), a heterogeneous autoimmune disease characterized primarily by inflammatory skin lesions. METHODS: The number of Treg in skin specimens obtained from patients with various subtypes of CLE was investigated by immunohistochemical analysis, using anti-Foxp3 and anti-CD4 monoclonal antibodies. Furthermore, characterization of peripheral blood CD4+,CD25+ Treg from normal healthy donors and patients with CLE was carried out by flow cytometry, analyzing the expression of Foxp3 and Treg subpopulations. We also purified CD4+,CD25(high) Treg obtained from patients with CLE and tested the sensitivity of these cells to CD95L-mediated apoptosis. RESULTS: Quantitative analysis of CD4+ T cells in skin lesions from patients with CLE revealed that the number was similar to that in lesions from patients with other chronic inflammatory diseases, but the number of Foxp3+ Treg in CLE was significantly reduced. There was no correlation between disease subtype and the frequency of Foxp3+ Treg in the skin of patients with CLE. In peripheral blood, no significant differences were observed in the number and phenotype of CD4+,CD25+ Treg or in the sensitivity to apoptosis of CD4+,CD25(high) Treg derived from patients with CLE and those derived from normal healthy donors. CONCLUSION: These data suggest that an organ-specific abnormality of Treg in the skin underscores the importance of analyzing Treg in the affected tissue. Such a local process might give insight into the pathogenic mechanisms of CLE and differs from a global peripheral dysfunction as reported for patients with a systemic manifestation of the disease.     

Variation in nursing home antipsychotic prescribing rates

BACKGROUND: Excessive prescribing of antipsychotic therapy is a concern owing to their potential to cause serious adverse events. We explored variation in the use of antipsychotic therapy across nursing homes in Ontario, Canada, and determined if prescribing decisions were based on clinical indications. METHODS: A point-prevalence study of antipsychotic therapy use in 47 322 residents of 485 provincially regulated nursing homes in December 2003. Facilities were classified into quintiles according to their mean antipsychotic prescribing rates. Residents were grouped into those with a potential clinical indication or no identified clinical indication for antipsychotic therapy. RESULTS: A total of 15 317 residents (32.4%) were dispensed an antipsychotic agent. The mean rate of antipsychotic prescribing by home ranged from 20.9% in the quintile of facilities with the lowest mean prescribing rates (quintile 1) to 44.3% in facilities with the highest mean prescribing rates (quintile 5). Compared with individuals residing in nursing homes with the lowest mean antipsychotic prescribing rates, those residing in facilities with the highest rates were 3 times more likely to be dispensed an antipsychotic agent (adjusted odds ratio [AOR], 3.0; 95% confidence interval [CI], 2.74-3.19). Similar rates were observed among residents with psychoses with or without dementia (AOR, 2.7; 95% CI, 2.35-3.09) and residents without psychoses or dementia (AOR, 2.9; 95% CI, 2.19-3.81) who had no identifiable indication for an antipsychotic therapy. CONCLUSION: Residents in facilities with high antipsychotic prescribing rates were about 3 times more likely than those in facilities with low prescribing rates to be dispensed an antipsychotic agent, irrespective of their clinical indication.     

Hypoxia-inducible expression of the mouse carbonic anhydrase IX demonstrated by new monoclonal antibodies

CA IX is a transmembrane carbonic anhydrase isoenzyme predominantly expressed in human tumors in response to hypoxia and functionally implicated in adaptation of tumor cells to hypoxic stress via control of pH and cell adhesion. Intense investigations of the human CA IX as a hypoxic marker and a therapeutic target have been facilitated by specific monoclonal antibodies. However, no such reagents existed for the mouse CA IX ortholog. We generated five new anti-mouse CA IX monoclonal antibodies AM1-4, AM4-3, AM27-4, AM34-7 and AM35-1 produced using CA IX-deficient mice. The antibodies are suitable for various immunodetection methods including immunoblotting and immunohistochemistry. Using these reagents we show that the mouse CA IX is expressed in three out of nine tested mouse cell lines, namely in L929, MEF and TSA and is regulated by hypoxia and cell density similarly to human CA IX. We also demonstrate that the mouse CA IX exhibits hypoxia-related expression pattern in multicellular spheroids and in tumor xenografts. Our results indicate the use of the mouse model as suitable for further studies of CA IX role in tumor development and for its pre-clinical investigations. The new monoclonal antibodies represent potent tools for accomplishment of these future studies.     

S-adenosyl-L-methionine co-administration prevents the ethanol-elicited dissociation of hepatic mitochondrial ribosomes in male rats

Background:  Chronic ethanol feeding to male rats has been shown to result in decreased mitochondrial translation, depressed respiratory complex levels and mitochondrial respiration rates. In addition, ethanol consumption has been shown to result in an increased dissociation of mitoribosomes. S-adenosyl-L-methionine (SAM) is required for the assembly and subsequent stability of mitoribosomes and is depleted during chronic ethanol feeding. The ability of dietary SAM co-administration to prevent these ethanol-elicited lesions was investigated.
Methods:  Male Sprague-Dawley rats were fed a nutritionally adequate liquid diet with ethanol comprising 36% of the calories according to a pair-fed design for 28 days. For some animals, SAM was supplemented in the diet at 200 mg/l. Liver mitochondria were prepared and mitoribosomes isolated. Respiration rates, ATP levels, respiratory complex levels, and the extent of mitoribosome dissociation were determined.
Results:  Twenty-eight days of ethanol feeding were found to result in decreased SAM content, depressed respiration, and increased mitoribosome dissociation. No changes in mitochondrial protein content; levels of respiratory complexes I, III, and V; complex I activities; and ATP levels were detected. Co-administration of SAM in the diet was found to prevent ethanol-induced SAM depletion, respiration decreases and mitoribosome dissociation.
Conclusions:  Taken together, these findings suggest (1) that mitoribosome dissociation precedes respiratory complex depressions in alcoholic animals and (2) that dietary supplementation of SAM prevents some of the early mitochondrial lesions associated with chronic ethanol consumption.     

Allogeneic blood SCT for children with Hurler's syndrome: results from the German multicenter approach MPS-HCT 2005

Hurler's syndrome is an inborn error of mucopolysaccharide metabolism leading to premature death in childhood. Allogeneic hematopoietic SCT can achieve long-term survival by correcting the enzymatic deficiency. In an attempt to improve long-term engraftment and to reduce regimen-related toxicity (RRT), a prospective multicenter approach was initiated in Germany using a fludarabine-based radiation-free preparative regimen. Between 2001 and 2008, 12 children were enrolled. Median age at SCT was 14 months (range, 4-31 months). The conditioning regimen contained fludarabine, BU, melphalan and antithymocyte globulin. CD34 positively selected PBSC were used in 10 children with a matched unrelated donor. Median cell dose was 24.6 x 10(6) CD34+ cells per kg (range 10.0-54.8). Two children with a matched sibling donor received non-manipulated BM. Donor lymphocyte infusions were given in 6/12 children for mixed hematopoietic chimerism. At a median follow-up of 29 months (range 2-85 months), all children engrafted and have either stabilized or improved neurological function. In total, 12/12 patients showed donor-derived engraftment with 9/12 having full and 3/12 having mixed hematopoiesis. One developed acute GVHD >or=grade II. RRT >or=grade II was observed in two patients.     

Results of modified Norwood's operation for hypoplastic left heart syndrome.

OBJECTIVE: The aim of the study was to analyze intermediate results of treatment of the hypoplastic left heart syndrome based on selective indication criteria. METHODS: Between February 1997 and May 1999 38 patients with hypoplastic left heart syndrome (n=35), or with functional variant of hypoplastic left heart syndrome (n=3) were admitted to our department. Contraindications for surgery were birth weight <2500 g, diameter of ascending aorta <2 mm, severe tricuspid regurgitation persisting after initial stabilization, pulmonary regurgitation more than mild, dysfunction of the systemic right ventricle and failure to effectively resuscitate circulation before surgery. RESULTS: Based on these criteria surgery was not indicated in 17 patients. Twenty-one infants were operated on by modified Norwood's procedure using only autologous great vessel tissue for reconstruction of systemic outflow. Overall hospital mortality was 14% (three patients). Eighteen survivors (86%) were discharged with well-balanced circulation. There was one late death (5%). Thirteen patients had already undergone the second stage (bi-directional Glenn) with no death. The mean follow-up was 13. 2+/-9.1 months (range 4-32 months). Considering both early and late events the probability of survival for the whole group (n=21) from the time of surgery was 86% at 1 month, 80% at 12 months, and it remained unchanged at 18 and 24 months of follow-up. CONCLUSIONS: Only a limited number of European countries offer surgical treatment of hypoplastic left heart syndrome. Promising intermediate results (80% survival rate after stage I and II) achieved at our department do not only reflect overcoming the learning curve but also a selective approach to indication for surgery as well. In a country with limited resources selective approach to the patients with hypoplastic left heart syndrome is justified.     

Cadmium blood concentrations in relation to nutrition

Cadmium is a toxic element ubiquitous in the environment, which damages biological systems in various ways. The major source of cadmium exposure is food. High cadmium content in the soil leads to high cadmium concentrations in certain plants such as grains (above all surface layers and germs), oil or non-oil seeds, fruit and vegetables. These food commodities are the crucial components of a vegetarian nutrition. Blood cadmium concentrations were measured in two non-smoking population groups: the vegetarian group (n = 80) and the non-vegetarian (control) group of general population on traditional mixed diet (n = 84). The significantly higher blood cadmium content (1.78 +/- 0.22 vs. 0.45 +/- 0.04 microg/l) was measured in vegetarian group. Healthy risk values > 5 microg/l were found in 6 vegetarians vs. no non-vegetarian. The highest cadmium concentration (3.15 +/- 0.77 microg/l) was measured in vegan subgroup (plant food only, n = 10) and that value decreased with increasing animal food consumption (1.75 +/- 0.36 microg/l, lactovegetarian and lactoovovegetarian subgroup/added dairy products and eggs, n = 41/, 1.34 +/- 0.21 microg/I, semivegetarian subgroup /as a previous subgroup and added white meat, n = 291). Risk vegetarians vs. non-risk vegetarians consume significantly higher amounts of whole grain products, grain sprouts and oil seeds. Blood cadmium content is directly influenced by age (r = 0.32, p < 0.001), by whole grain product intake (r = 0.66, p < 0.001) and by duration of vegetarianism (r = 0.5, p < 0.001). Oxidative stress plays a major role in chronic cadmium induced hepatic and renal toxicity as well as in other consequences of cadmium injuries. Vegetarians have significantly higher plasma concentrations of natural antioxidants. The sufficient antioxidative protection against cadmium induced free radical formation in vegetarians may inhibit the harmful effects of greater cadmium intake from plant food.