Shared-care survivorship program for testicular cancer patients: safe and feasible.

BACKGROUND: Testicular cancer survivors are at risk for cardiovascular disease, often preceded by early development of cardiovascular risk factors due to chemotherapeutic treatment. Therefore, close collaboration between oncologists and primary care physicians (PCPs) is needed during follow-up to monitor and manage cardiovascular risk factors. We designed a shared-care survivorship program, in which testicular cancer patients visit both their oncologist and their PCP. The objective of this study was to test the safety and feasibility of shared-care follow-up after treatment for metastatic testicular cancer. PATIENTS AND METHODS: The study was designed as an observational cohort study with a stopping rule to check for the safety of follow-up. Safety boundaries were defined for failures in the detection of signals indicating cancer recurrence. Secondary outcomes were the proportion of carried out cardiovascular risk assessments, psychosocial status and patient preferences measured with an evaluation questionnaire. RESULTS: One hundred and sixty-two patients were enrolled (69% of eligible testicular cancer patients). Almost all (99%, n = 150) PCPs of the enrolled patients agreed to participate in the study. In total, 364 primary care visits took place. No failures occurred in the detection of relapsed testicular cancer. Four follow-up visits were considered as failures because of organizational issues, without activation of the stopping rule. Eventually, the safe boundary was crossed indicating that this shared-care model is a safe alternative for follow-up after testicular cancer. Patients were satisfied with the knowledge level of PCPs. PCPs were willing to further extend their role in follow-up care after cancer. CONCLUSIONS: Shared-care follow-up is safe and feasible in this patient population. Patients benefit from personalized care, partly close to their home. Within shared care, PCPs can have an important role in cardiovascular risk management and psychosocial survivorship issues.

Predictors of adherence to exercise interventions during and after cancer treatment: A systematic review.

OBJECTIVE: Exercise interventions benefit cancer patients. However, only low numbers of patients adhere to these interventions. This review aimed to identify predictors of exercise intervention adherence in patients with cancer, during and after multimodality cancer treatment. METHODS: A literature search was performed using electronic databases (PubMed, Embase, and Cochrane) to identify relevant papers published before February 1, 2017. Papers reporting randomized controlled trials, conducted in adult cancer patients who participated in an exercise intervention during and/or after multimodality cancer treatment, and providing outcome of factors predicting exercise adherence were included. Papers were assessed for methodological quality by using the Physiotherapy Evidence Database scale. RESULTS: The search identified 720 potentially relevant papers, of which 15 fulfilled the eligibility criteria. In these 15 studies, 2279 patients were included and 1383 of these patients were randomized to an exercise intervention. During cancer treatment, the factors predicting exercise adherence were as follows: location of the rehabilitation center, extensive exercise history, high motivation for exercise, and fewer exercise limitations. After cancer treatment, factors that predicted adherence were as follows: less extensive surgery, low alcohol consumption, high previous exercise adherence, family support, feedback by trainers, and knowledge and skills of exercise. Methodological quality of the included papers was rated "high". CONCLUSIONS: The most prominent predictors of adherence to exercise interventions were location of the rehabilitation center, extensive exercise history, high motivation for exercise, and fewer exercise limitations. To increase the number of cancer patients who will benefit, these results should be considered into the development and implementation of future exercise interventions.

Predictors of colorectal neoplasia after polypectomy: based on initial and consecutive findings.

BACKGROUND: Colorectal adenoma patients are kept under surveillance because of the risk of developing metachronous neoplasia. The aim is to determine predictors of neoplasia development after polypectomy. METHODS: It is an observational cohort study. 433 Patients who had ≥1 adenoma removed between 1988 and 2004 were included, with follow-up until 2010. Multivariate analysis of patient and adenoma characteristics was performed at initial colonoscopy and at consecutive positive examinations. The main outcome measured was the development of metachronous (advanced) adenomas during follow-up. RESULTS: Median follow-up was 85 months. Multivariate analysis identified male sex, ≥3 adenomas, high-grade dysplasia and age ≥55 years as risk factors for metachronous lesions at first surveillance. Analysis using life expectancy as a timescale showed ≥3 adenomas to be the only predictive factor. The time to second or third metachronous adenoma did not depend on the number of adenomas. Patients with ≥3 adenomas were five years older at the time of their first polypectomy compared with those with fewer adenomas, but of the same age at the first recurrence. Prevalence of high-grade dysplasia was associated with age and high-grade dysplasia in the prior adenoma independent of time interval. CONCLUSIONS: Adenoma development after polypectomy occurs in a regular and repetitive way. Our data suggest that only the interval between the initial colonoscopy and the first follow-up colonoscopy should be based on initial findings, i.e. number of adenomas, and that subsequent colonoscopies can be planned at predetermined intervals.

Regulation of TRAIL receptor expression by ß-catenin in colorectal tumours.

Tumour-necrosis-factor-related apoptosis-inducing ligand (TRAIL) is being investigated as a targeted cancer therapeutic and the expression of its pro-apoptotic receptors, DR4 and DR5, increases during colorectal carcinogenesis. This study investigated the role of ß-catenin in the regulation of these receptors. In human colorectal adenoma and carcinoma cell lines, downregulation of ß-catenin resulted in lower total DR4 and DR5 protein levels. Similarly, cell membrane expression of DR4 and DR5 was reduced after downregulation of ß-catenin in colon carcinoma cells, whereas induction of ß-catenin in HeLa cells led to increased cell membrane expression of DR4 and DR5. Downregulation of ß-catenin decreased the recombinant human TRAIL sensitivity of human colon carcinoma cells. Activation of the transcription factor T-cell factor-4 (TCF-4) is an important function of ß-catenin. Dominant-negative TCF-4 overexpression, however, did not significantly affect TRAIL receptor expression or recombinant human TRAIL sensitivity. Human colorectal adenomas (N = 158) with aberrant (cytoplasmic and nuclear) ß-catenin expression had a higher percentage of immunohistochemical DR4 and DR5 staining per tumour (mean: 73 and 88%, respectively) than those with membranous ß-catenin staining only (mean: 50 and 70%, respectively, P < 0.01 for both). Furthermore, aberrant ß-catenin staining co-localized with DR4 and DR5 expression in 92% of adenomas. In 53 human colorectal carcinomas, aberrant ß-catenin expression was present in most cases and DR4/5 expression was largely homogenous. Similarly, in adenomas from APC(min) mice, cytoplasmic ß-catenin staining co-localized with staining for the murine TRAIL death receptor. In conclusion, the gradual increase in TRAIL receptor expression during colorectal carcinogenesis is at least partially mediated through increased ß-catenin expression, independently of TCF-4-signalling.

Defective NDUFA9 as a novel cause of neonatally fatal complex I disease.

BACKGROUND: Mitochondrial disorders are associated with abnormalities of the oxidative phosphorylation (OXPHOS) system and cause significant morbidity and mortality in the population. The extensive clinical and genetic heterogeneity of these disorders due to a broad variety of mutations in several hundreds of candidate genes, encoded by either the mitochondrial DNA (mtDNA) or nuclear DNA (nDNA), impedes a straightforward genetic diagnosis. A new disease gene is presented here, identified in a single Kurdish patient born from consanguineous parents with neonatally fatal Leigh syndrome and complex I deficiency. METHODS AND RESULTS: Using homozygosity mapping and subsequent positional candidate gene analysis, a total region of 255.8 Mb containing 136 possible mitochondrial genes was identified. A pathogenic mutation was found in the complex I subunit encoding the NDUFA9 gene, changing a highly conserved arginine at position 321 to proline. This is the first disease-causing mutation ever reported for NDUFA9. Complex I activity was restored in fibroblasts of the patient by lentiviral transduction with wild type but not mutant NDUFA9, confirming that the mutation causes the complex I deficiency and related disease. CONCLUSIONS: The data show that homozygosity mapping and candidate gene analysis remain an efficient way to detect mutations even in small consanguineous pedigrees with OXPHOS deficiency, especially when the enzyme deficiency in fibroblasts allows appropriate candidate gene selection and functional complementation.

The value of detectable thyroglobulin in patients with differentiated thyroid cancer after initial ¹³¹I therapy.

OBJECTIVE: To assess the prognostic value of detectable thyroglobulin (Tg) after initial surgery and radioactive iodine (¹³¹I) therapy by comparing patients with a negative post-therapeutic whole body scan (WBS) with either detectable or undetectable Tg. BACKGROUND: Differentiated thyroid cancer has a good prognosis. However, recurrences can occur up to 30 years after initial treatment. Because life-long follow-up is necessary, it is important to explore possible risk factors associated with recurrence and mortality. DESIGN, PATIENTS AND MEASUREMENTS: We studied 539 patients who were treated between 1980 and 2007. After the last therapeutic dosage of 5550 MBq ¹³¹I, 72 patients had negative post-therapeutic WBS and positive Tg levels (Tg+ group) and 399 patients had negative post-therapeutic WBS and negative Tg (Tg- group). The 68 remaining patients had proven residual macroscopic disease. We investigated recurrences and overall mortality in the Tg+ and Tg- group compared with the Dutch population. RESULTS: In the Tg+ group, detectable recurrences occurred significantly earlier and more frequently than in the Tg- group (19%vs 13%, P = 0·024). Survival between these groups was comparable, but shorter than the general Dutch population [Standardised Mortality Rate (SMR) 1·38 (95% CI 1·12;1·63) (P = 0·003)]. Disease-free survival in the Tg groups was comparable and not significantly different from the Dutch population [SMR = 1·09 (95% CI 0·81;1·34) (P = 0·569)]. CONCLUSION: Patients with detectable Tg during the last ¹³¹I treatment and a negative post-therapeutic WBS have significant earlier and more recurrences than patients without detectable Tg. Survival in both groups is comparable. After initial therapy, the combination of a negative high dose post-therapeutic WBS with detectable Tg is a valuable predictor for earlier and more recurrences, but is not associated with survival.

Deficiencies in fat-soluble vitamins in long-term users of somatostatin analogue.

BACKGROUND: Somatostatin analogues are administered to control hormone hypersecretion in acromegaly and carcinoid patients. Somatostatin analogues can increase fat in the stools, which can lead to loss of fat-soluble vitamins. The effect of long-term somatostatin analogue use on vitamin levels remains unknown. AIM: To investigate the prevalence of fat-soluble vitamin deficiencies in long-term somatostatin analogue users. METHODS: All acromegaly and carcinoid patients using somatostatin analogues for ≥ 18 months visiting the University Medical Center Groningen between December 2008 and April 2009 were eligible. Vitamin levels of fat-soluble vitamins in blood, clinical and vitamin-dependent laboratory parameters were collected. RESULTS: In all, 19 acromegaly and 35 carcinoid patients were included. Twelve patients experienced steatorrhoea; two carcinoid patients experienced night blindness. Forty-two (78%) were deficient for one or more vitamins, and 32% (n = 17) had multiple deficiencies. Deficiencies for vitamin A, D, E, K1 and E in erythrocytes occurred in 6%, 28%, 15%, 63% and 58% of the patients. Prevalence of vitamin D, E and K1 deficiencies was similar in both patient groups. Treatment duration did not influence vitamin levels. The length of intestinal resection and age correlated negatively with vitamin A levels. CONCLUSIONS: Fat-soluble vitamin deficiencies are frequent during long-term somatostatin analogue treatment. Therefore, fat-soluble vitamins should be monitored in these patients.

Plasma lecithin: cholesterol acyltransferase activity modifies the inverse relationship of C-reactive protein with HDL cholesterol in nondiabetic men.

Lecithin:cholesterol acyltransferase (LCAT) is instrumental in high-density lipoprotein (HDL) maturation, but high LCAT levels do not predict low cardiovascular risk. LCAT may affect antioxidative or anti-inflammatory properties of HDL. We determined the relationship of plasma high-sensitivity C-reactive protein (CRP) with LCAT activity and evaluated whether LCAT activity modifies the decreasing effect of HDL cholesterol (HDL-C) on CRP, as an estimate of its anti-inflammatory properties. Plasma HDL-C, apolipoprotein (apo) A-I and LCAT activity (exogenous substrate method) were measured in 260 nondiabetic men without cardiovascular disease. CRP was correlated inversely with HDL-C and apo A-I, and positively with LCAT activity (P<0.01 to 0.001). Multivariate regression analysis demonstrated that age- and smoking-adjusted plasma CRP levels were associated negatively with HDL-C (beta=-0.224, P<0.001) and positively with LCAT activity (beta=0.119, P=0.034), as well as with the interaction between HDL-C and LCAT activity (beta=0.123, P=0.026). There was also an interaction between apo A-I and LCAT activity on CRP (beta=0.159, P=0.005). These relationships remained similar after adjustment for apo B-containing lipoproteins. In conclusion, the inverse relationship of HDL-C with CRP is attenuated by LCAT activity at higher HDL-C levels. It is hypothesized that LCAT could mitigate HDL's anti-inflammatory or antioxidative properties at higher HDL-C concentrations.

Defective complex I assembly due to C20orf7 mutations as a new cause of Leigh syndrome.

BACKGROUND: Leigh syndrome is an early onset, progressive, neurodegenerative disorder with developmental and motor skills regression. Characteristic magnetic resonance imaging abnormalities consist of focal bilateral lesions in the basal ganglia and/or the brainstem. The main cause is a deficiency in oxidative phosphorylation due to mutations in an mtDNA or nuclear oxidative phosphorylation gene. METHODS AND RESULTS: A consanguineous Moroccan family with Leigh syndrome comprise 11 children, three of which are affected. Marker analysis revealed a homozygous region of 11.5 Mb on chromosome 20, containing 111 genes. Eight possible mitochondrial candidate genes were sequenced. Patients were homozygous for an unclassified variant (p.P193L) in the cardiolipin synthase gene (CRLS1). As this variant was present in 20% of a Moroccan control population and enzyme activity was only reduced to 50%, this could not explain the rare clinical phenotype in our family. Patients were also homozygous for an amino acid substitution (p.L159F) in C20orf7, a new complex I assembly factor. Parents were heterozygous and unaffected sibs heterozygous or homozygous wild type. The mutation affects the predicted S-adenosylmethionine (SAM) dependent methyltransferase domain of C20orf7, possibly involved in methylation of NDUFB3 during the assembly process. Blue native gel electrophoresis showed an altered complex I assembly with only 30-40% of mature complex I present in patients and 70-90% in carriers. CONCLUSIONS: A new cause of Leigh syndrome can be a defect in early complex I assembly due to C20orf7 mutations.

Prevalence of paraneoplastic hyperthyroidism in patients with metastatic non-seminomatous germ-cell tumors.

BACKGROUND: Patients with elevated human chorionic gonadotrophin (HCG) can have hyperthyroidism. We assessed the prevalence of hyperthyroidism in patients presenting with disseminated non-seminomatous germ-cell tumors (NSGCT). PATIENTS AND METHODS: In all patients with metastatic NSGCT who started chemotherapy at our center from April 2001 to April 2007, thyroid function was analyzed. The association between thyroid function and HCG level was examined and the frequency of hyperthyroidism in patients with low (<5000 IU/l), intermediate (> or = 5000 but <50 000 IU/l) and high (> or = 50 000 IU/l) serum HCG was assessed. RESULTS: For 144 of 148 eligible patients, thyroid function tests were available. Five patients with hyperthyroidism (3.5%) were identified, who all had high-serum HCG (mean 1 325 147 IU/l). Fifty percent of the patients with high HCG levels had hyperthyroidism versus 0% of the patients with HCG <50 000 IU/l (P < 0.001). Free thyroxin levels normalized within 26 days after starting chemotherapy in all patients. CONCLUSIONS: Hyperthyroidism frequently accompanies NSGCT with highly elevated HCG. Since its symptoms overlap with those of extensive metastatic disease, it may not be recognized. Thyroid function should be assessed in patients with high HCG levels and symptomatic hyperthyroidism should be treated temporarily with beta-blockade or antithyroidal medication.

Serum paraoxonase-I activity is unaffected by short-term administration of simvastatin, bezafibrate, and their combination in type 2 diabetes mellitus.

BACKGROUND: The high-density lipoprotein (HDL)-associated anti-oxidative and anti-inflammatory enzyme, paraoxonase-I, has been found previously to be lower in type 2 diabetes mellitus. We studied whether statin and fibrate treatment, alone and in combination, affect serum paraoxonase-I activity in conjunction with changes in HDL cholesterol in diabetic patients. SUBJECTS AND METHODS: A placebo-controlled crossover study was carried out in 14 type 2 diabetic patients to test the effect of 8 weeks of active treatment with simvastatin (40 mg daily), bezafibrate (400 mg daily), and their combination on serum paraoxonase-I activity, measured as its activity towards arylesterase and paraoxon. Serum paraoxonase-I activity was also compared between these diabetic patients and 49 non-diabetic control subjects. RESULTS: Serum arylesterase activity was lower in type 2 diabetic patients compared to control subjects (P < 0.001), but the difference in paraoxonase activity was not significant (P = 0.22). Neither arylesterase (P = 0.24) nor paraoxonase activity (P = 0.37) was increased in response to treatment, despite higher HDL cholesterol and apolipoprotein A-I during combination therapy (P < 0.05 for both). CONCLUSION: Short-term administration of simvastatin and bezafibrate, even when combined, is ineffective in raising serum paraoxonase-I activity in type 2 diabetes.

Skin autofluorescence provides additional information to the UK Prospective Diabetes Study (UKPDS) risk score for the estimation of cardiovascular prognosis in type 2 diabetes mellitus.

AIMS/HYPOTHESIS: The UK Prospective Diabetes Study (UKPDS) risk engine has become a standard for cardiovascular risk assessment in type 2 diabetes mellitus. Skin autofluorescence was recently introduced as an alternative tool for cardiovascular risk assessment in diabetes. We investigated the prognostic value of skin autofluorescence for cardiovascular events in combination with the UKPDS risk engine in a cohort of patients with type 2 diabetes managed in primary care. METHODS: Clinical, UKPDS risk engine and skin autofluorescence data were obtained at baseline in 2001-2002 in the type 2 diabetes group (n = 973). Follow-up data concerning fatal and non-fatal cardiovascular events (primary endpoint) were obtained till 2005. Patients were classified as 'low risk' when their 10 year UKPDS risk score for fatal cardiovascular events was <10%, and 'high risk' if >10%. Skin autofluorescence was measured non-invasively with an autofluorescence reader. Skin autofluorescence was classified by the median (i.e. low risk < median, high risk > median). RESULTS: The incidence of cardiovascular events was 119 (44 fatal, 75 non-fatal). In multivariate analysis, skin autofluorescence, age, sex and diabetes duration were predictors for the primary endpoint. Addition of skin autofluorescence information to that from the UKPDS risk engine resulted in re-classification of 55 of 203 patients from the low-risk to the high-risk group. The 10 year cardiovascular event rate was higher in patients with a UKPDS score >10% when skin autofluorescence was above the median (55.8% vs 38.9%). CONCLUSIONS/INTERPRETATION: Skin autofluorescence provides additional information to the UKPDS risk engine which can result in risk re-classification of a substantial number of patients. It furthermore identifies patients who have a particularly high risk for developing cardiovascular events.

Termination of damaged protein repair defines the occurrence of symptoms in carriers of the m.3243A > G tRNA(Leu) mutation.

BACKGROUND: The m.3243A>G mutation in the mitochondrial tRNA(Leu(UUR)) gene is an example of a mutation causing a very heterogeneous phenotype. It is the most frequent cause (80%) of the MELAS syndrome (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes), but it can also lead in addition or separately to type 2 diabetes, deafness, renal tubulopathy and/or cardiomyopathy. METHODS: To identify pathogenic processes induced by this mutation, we compared global gene expression levels of muscle biopsies from affected and unaffected mutation carriers with controls. RESULTS AND CONCLUSIONS: Gene expression changes were relatively subtle. In the asymptomatic group 200 transcripts were upregulated and 12 were downregulated, whereas in the symptomatic group 15 transcripts were upregulated and 52 were downregulated. In the asymptomatic group, oxidative phosphorylation (OXPHOS) complex I and IV genes were induced. Protein turnover and apoptosis were elevated, most likely due to the formation of dysfunctional and reactive oxygen species (ROS) damaged proteins. These processes returned to normal in symptomatic patients. Components of the complement system were upregulated in both groups, but the strongest in the symptomatic group, which might indicate muscle regeneration--most likely, protein damage and OXPHOS dysfunction stimulate repair (protein regeneration) and metabolic adaptation (OXPHOS). In asymptomatic individuals these processes suffice to prevent the occurrence of symptoms. However, in affected individuals the repair process terminates, presumably because of excessive damage, and switches to muscle regeneration, as indicated by a stronger complement activation. This switch leaves increasingly damaged tissue in place and muscle pathology becomes manifest. Therefore, the expression of complement components might be a marker for the severity and progression of MELAS clinical course.

The diagnostic value of 124I-PET in patients with differentiated thyroid cancer.

BACKGROUND: The purpose of this prospective study was to evaluate the clinical diagnostic value of iodine-124 (124I)-positron emission tomography (PET) in patients with advanced differentiated thyroid carcinoma (DTC) and to compare the 124I-PET imaging results with the 131I whole-body scan (WBS). MATERIALS AND METHODS: Twenty patients with histologically proven advanced DTC (including T4, extra-nodal tumour growth, or distant metastases) underwent diagnostic 131I-WBS, 124I-PET scan, and post-treatment 131I-WBS 4 months after ablation. The findings on the 124I-PET were compared with the findings on the diagnostic and post-therapeutic 131I-WBS and were also correlated with radiologic and/or cytological investigations. RESULTS: 124 I-PET vs diagnostic 131 I-WBS. Eleven patients showed uptake on the 124I-PET. Only 3 of these 11 patients also showed uptake on the diagnostic 131I scan, but the uptake was more clearly visible and the abnormalities were more extensive on the 124I-PET. 124 I-PET vs post-treatment 131 I-WBS. Eleven patients showed uptake on the 124I-PET, which was also visible on the post-treatment scan in nine patients; in the other two patients, no uptake was observed on the post-treatment scan and no anatomical localisation could be confirmed. Two patients showed only uptake on the post-treatment scan without uptake on the 124I-PET: in one, the uptake was confirmed by MRI, and in the other, no anatomical localisation was found. In seven patients, no uptake was observed on both the scans. CONCLUSION: 124I-PET proved to be a superior diagnostic tool as compared to low-dose diagnostic 131I scans and adequately predicted findings on subsequent high-dose post-treatment 131I scans.

111Indium-trastuzumab visualises myocardial human epidermal growth factor receptor 2 expression shortly after anthracycline treatment but not during heart failure: a clue to uncover the mechanisms of trastuzumab-related cardiotoxicity.

AIM: Trastuzumab can induce cardiotoxicity, particularly when combined with anthracyclines. Myocardial human epidermal growth factor receptor 2 (HER2) expression may be transiently upregulated by a compensatory mechanism following cardiac stress. 111In-DTPA-trastuzumab, scintigraphy can detect HER2 positive tumour lesions, however previously, we found myocardial uptake in only 1 of the 15 anthracycline-pre-treated patients with a median of 11 months after the last anthracycline administration. To evaluate whether myocardial HER2 expression is upregulated by anthracycline-induced cardiac stress or in case of heart failure by chronic pressure or volume overload, we performed 111In-DTPA-trastuzumab scans in patients shortly after anthracyclines and with non-anthracycline-related heart failure. METHODS: Patients within 3 weeks after undergoing 4-6 cycles first-line anthracycline-based chemotherapy and patients with heart failure due to cardiac disease underwent gammacamera imaging 48 and 96 h after 111In-DTPA-trastuzumab intravenously. RESULTS: Myocardial 111In-DTPA-trastuzumab uptake was observed in 5 out of 10 anthracycline-treated patients, who all were without symptomatic cardiac dysfunction. None of the 10 heart failure patients showed myocardial uptake. CONCLUSION: Shortly after completion of anthracycline treatment, myocardial HER2 over-expression was detectable in 50% of the patients. 111In-DTPA-trastuzumab scintigraphy after anthracyclines prior to adjuvant trastuzumab potentially identifies patients susceptible for trastuzumab-related cardiotoxicity and thus may facilitate the optimal timing of trastuzumab therapy.

A simplified and reliable assay for complex I in human blood lymphocytes.

Complex I activity of the mitochondrial respiratory chain is difficult to measure in blood lymphocytes because of the limited access of substrates to the enzyme complex in these cells. The results of the present study show that permeabilization of human blood lymphocytes in the presence of protease inhibitors by three cycles of freeze-thawing enables reproducible detection of the rotenone-sensitive complex I activity. To that end, the water-soluble coenzyme Q(10) analogue CoQ(1) and a relatively high concentration of blood lymphocytes were combined in small quartz cuvettes so that the amount of blood needed for this assay remained low. The relationship between the initial rate of NADH oxidation by complex I and the protein concentration was quasi-linear. The fractional inhibition of the total NADH:CoQ(1) oxidoreductase by a saturating concentration of rotenone decreased sharply at CoQ(1) concentrations higher than 20 muM, which is indicative, but does not prove the involvement of a second CoQ(1) binding site at complex I. Since the present complex I assay requires only a small amount of blood, the functionality of this important respiratory chain complex can be assessed in an easy and reliable manner not only in adult patients but also in children suspected to have a mitochondrial disease.

Plasma cholesteryl ester transfer protein mass and phospholipid transfer protein activity are associated with leptin in type 2 diabetes mellitus.

Adipose tissue contributes to plasma levels of lipid transfer proteins and is also the major source of plasma adipokines. We hypothesized that plasma cholesteryl ester transfer protein (CETP) mass, phospholipid transfer protein (PLTP) activity and cholesteryl ester transfer (CET, a measure of CETP action) are determined by adipokine levels. In this study, relationships of plasma CETP mass, PLTP activity and CET with leptin, resistin and adiponectin were analyzed in type 2 diabetic patients and control subjects. Plasma PLTP activity (P<0.001), CET (P<0.001), leptin (P=0.003), resistin (P<0.001), high sensitive C-reactive protein (P=0.005), and insulin resistance (HOMA(ir)) (P<0.001) were higher, whereas HDL cholesterol (P<0.001) and plasma adiponectin (P<0.001) were lower in 83 type 2 diabetic patients (32 females) than in 83 sex-matched control subjects. Multiple linear regression analysis demonstrated that in diabetic patients plasma leptin levels were related to plasma CETP mass (P=0.018) and PLTP activity (P<0.001), but not to the other adipokines measured. Plasma CET was inversely correlated with adiponectin in univariate analysis, but this association disappeared in multivariate models that included plasma lipids and CETP. In conclusion, both plasma CETP mass and PLTP activity are associated with plasma leptin in type 2 diabetes. The elevated CET in these patients is not independently related to any of the measured plasma adipokines.

The role of superoxide anions in the development of distant tumour recurrence.

We hypothesise that reactive oxygen species (ROS) released from activated polymorphonuclear leucocytes during surgery play a crucial role in enhanced tumour recurrence seen after surgery. Therefore, the effect of ROS on adhesion of tumour cells to microvascular endothelium in a reproducible human in vitro model was studied. Preincubation of microvascular endothelial cells with the superoxide anion producing xanthine-xanthine oxidase complex significantly increased adhesion of the human colon carcinoma cells HT29 (167% vs control, P < 0.01), Caco2 (164% vs control, P < 0.01) and of the pancreas carcinoma cells PanC1 (180% vs control, P < 0.01). Addition of the antioxidant enzymes superoxide dismutase or catalase significantly decreased tumour cell adhesion (P < 0.01). Exposure of endothelial cells to superoxide anions increased the apoptotic rate to 7.9 times the normal rate. Additionally, exposure increased expression of the endothelial adhesion molecules E-Selectin, ICAM-1, and VCAM-1 of maximally 170% vs control (P < 0.01). In conclusion, this study shows that superoxide anions promote the adherence of tumour cells to the microvasculature by inducing endothelial apoptosis that subsequently induces the expression of various adhesion molecules for tumour cells. This indicates that by tackling the production of ROS preventing tumour recurrence at distant sites might be feasible.