Testing a Prostate Cancer Educational Intervention in High-Burden Neighborhoods.

To better capitalize on our enhanced understanding of prostate cancer (PCa) risk factors, it is important to better understand how knowledge and attitudes contribute to ethnic disparities in PCa outcomes. The goal of this study was to test the impact of a targeted PCa educational intervention vs. a healthy lifestyle educational control intervention on levels of knowledge, concern, and intention to screen for PCa.We recruited 239 men from neighborhoods with the highest PCa burden in Philadelphia. We assigned 118 men from two of the neighborhoods to the control group 121 men from 2 other neighborhoods to the intervention group. Repeated outcome assessment measures were obtained by administering the survey at baseline, post-session, 1 month post-session, and 4 months post-session.We conducted descriptive statistics to characterize the study sample and linear mixed effect regression models to analyze the intervention's effect on the outcomes. At baseline, we observed no differences in the outcomes between the PCa-targeted intervention and healthy lifestyle control groups.We found that knowledge of PCa and intention to screen increased significantly over time for both the control and intervention groups (p ≤ 0.01 at the 4-month follow-up). In contrast, change in the level of PCa concern was only significant for the intervention group immediately post-session and at 1-month follow-up (p = 0.04 and p = 0.01, respectively).This study showed that gathering at-risk men for discussions about PCa or other health concerns may increase their PCa knowledge and intention to talk to a doctor about PCa screening.

Fast production of microwave component prototypes by additive manufacturing and copper coating.

We present a novel method for efficient production of prototypes of microwave components by fused depositing modeling, also known as 3D plastic printing, and vapor deposition coating of a 1 µm copper layer. We demonstrate that the properties of the components follow the predicted performance for low power microwave propagation. The production method offers new opportunities for cheap and efficient production of mock-ups and prototypes of advanced-geometry components for tests with low-power microwaves.

Impact of a multidisciplinary training programme on outcome of upper rectal cancer by critical appraisal of the extent of mesorectal excision with postoperative MRI.

BACKGROUND: Optimal management of patients with upper rectal cancer remains unclear. Partial mesorectal excision (PME) without neoadjuvant therapy is currently advocated for the majority of patients. Recent studies, however, reported a high risk of local recurrence and suboptimal surgery. The aim of this study was to evaluate the effects of a quality assurance initiative with postoperative MRI to improve outcomes in these patients. METHODS: Patients who underwent mesorectal excision with curative intent for rectal cancer in 2007-2013 were included. Postoperative MRI of the pelvis was performed 1 year after surgery. In 2011, a multidisciplinary workshop with focus on extent and completeness of surgery was held for training surgeons, pathologists and radiologists involved in treatment planning. Images of residual mesorectum and histopathological reports were reviewed with regard to the distal resection margin. Local recurrence after a minimum of 3 years' follow-up was compared between two cohorts from 2007-2010 and 2011-2013. RESULTS: A total of 627 patients were included; postoperative MRI of the pelvis was done in 381 patients. The 3-year actuarial local recurrence rate in patients with upper rectal cancer improved from 12·9 to 5·0 per cent (P = 0·012). After the workshop, fewer patients with cancer of the upper rectum were selected to have PME (90·8 per cent in 2007-2010 versus 80·2 per cent in 2011-2013; P = 0·023), and fewer patients who underwent PME had an insufficient distal resection margin (61·7 versus 31 per cent respectively; P < 0·001). CONCLUSION: Quality assessment of surgical practice may have a major impact on oncological outcome after surgery for upper rectal cancer.

ANTECEDENTES: El tratamiento óptimo para los pacientes con cáncer del tercio superior de recto no está claro. En este momento, la conducta más empleada es la exéresis parcial del mesorrecto (partial mesorectal excision, PME) sin tratamiento neoadyuvante. Sin embargo, estudios recientes han apuntado que se trata de una cirugía subóptima con un elevado riesgo de recidiva local. El objetivo de este estudio fue evaluar los efectos de una iniciativa de control de calidad con una resonancia magnética (magnetic resonance imaging, MRI) postoperatoria para mejorar los resultados en estos pacientes. MÉTODOS: Se incluyeron los pacientes con cáncer rectal a los que se realizó una exéresis del mesorrecto con intención curativa entre los años 2007 y 2013. Un año después de la cirugía se realizó una MRI de la pelvis. En el 2011, se organizó un taller multidisciplinario para educar a los cirujanos, patólogos y radiólogos involucrados en la planificación del tratamiento, en el que se discutieron la extensión y la radicalidad de la cirugía. Se revisaron las imágenes de mesorrecto residual y los informes histopatológicos respecto al margen de resección distal. Se comparó la recidiva local después de más de 3 años de seguimiento entre dos cohortes temporales, 2007-2010 y 2011-2013, respectivamente. RESULTADOS: Se incluyeron un total de 627 pacientes, en los que en 381 se realizó una MRI postoperatoria de la pelvis. Las tasa actuarial de recidiva local a 3 años en pacientes con cáncer del tercio superior de recto mejoraron del 12,9% al 5,0% (P = 0,012). Después del taller, se realizaron menos PME en pacientes con cáncer del tercio superior de recto (91% versus 80%, P = 0,023) y menos pacientes en los que se realizó una PME presentaron un margen de resección distal insuficiente (62% versus 31%, P < 0,001). CONCLUSIÓN: La evaluación de la calidad de la práctica quirúrgica puede tener un gran impacto en los resultados oncológicos después de la cirugía del cáncer del tercio superior de recto.

Overall risk and risk factors for metachronous peritoneal metastasis after colorectal cancer surgery: a nationwide cohort study.

BACKGROUND: This study aimed to identify the cumulative incidence and risk factors of metachronous peritoneal metastasis (M-PM) from colorectal cancer in patients who had intended curative treatment. METHODS: Patients with colorectal cancer were identified using the Danish Colorectal Cancer Group database for 2006-2015. The Danish Pathology Registry and the Danish National Patient Registry were used to identify M-PM to 2017. Risk factors were estimated by multivariable absolute risk regression, treating death and other cancers as competing risks. Overall risk and risk differences (RDs) were estimated at 1, 3 and 5 years. RESULTS: In 22 586 patients with colorectal cancer, the overall risk of M-PM was reported to be 0·9 (95 per cent c.i. 0·8 to 1·0) per cent at 1 year, 1·9 (1·8 to 2·1) per cent at 3 years and 2·2 (2·0 to 2·4) per cent at 5 years. Advanced tumour category ((y)pT4 versus (y)pT1) increased the RD of both M-PM (2·9 (95 per cent c.i. 2·1 to 3·7) at 1 year and 6·0 (4·9 to 7·2) at 3 years) and lymph node involvement ((y)pN2 versus (y)pN0) (2·5 (1·8 to 3·2) at year and 4·3 (3·2 to 5·3) at 3 years). No further increase in risk was observed at 5 years. In a subanalysis, tumour-involved resection margin (R1 versus R0) was associated with M-PM with a RD of 3·9 (1·6 to 6·2) at 1 year and 5·9 (2·6 to 9·3) at 3 years. CONCLUSION: The overall risk of M-PM in patients with colorectal cancer is low, but is increased in advanced T and N status. Follow-up of at least 3 years after colorectal cancer surgery may be necessary, given the potential curative treatment of early diagnosed M-PM.

ANTECEDENTES: Este estudio tuvo como objetivo identificar la incidencia acumulada y los factores de riesgo de metástasis peritoneales metacrónicas (metachronous peritoneal metastases, M-PM) del cáncer colorrectal en pacientes que se sometieron al tratamiento curativo previsto. MÉTODOS: Se identificaron los pacientes con cáncer colorrectal a partir de la base de datos del grupo danés de cáncer colorrectal (Danish Colorectal Cancer Group) durante el periodo 2006-2015. El Registro Danés de Patología (Danish Pathology Registry) y el Registro Nacional Danés de Pacientes (Danish National Patient Registry) se utilizaron para identificar los casos de M-PM hasta el 2017. Los factores de riesgo se estimaron mediante una regresión de riesgo absoluto multivariable, tratando la muerte y otros tipos de cáncer como riesgos competitivos. El riesgo general y las diferencias de riesgo (risk differences, RD) se estimaron a 1, 3 y 5 años. RESULTADOS: De los 22.586 pacientes con CCR, el riesgo global de M-PM fue del 0,9% (i.c. del 95%: 0,8 a 1,0) al año, 1,9 (i.c. del 95%: 1,8 a 2,1) a los 3 años y 2,2 (i.c. del 95%: 2,0 a 2.4) después de 5 años. El estadio T tumoral avanzado ((y) pT4 versus (y) pT1) aumentó el riesgo de M-PM, DR a 1 año: 2,9% (i.c. del 95%: 2,1 a 3,), 3 años: 6,0 (i.c. 95% 4,9 a 7,2), así como la afectación de los ganglios linfáticos ((y) pN2 versus (y) pN0), 1 año: 2,5 (i.c. 95% 1,8 a 3,2), 3 años: 4,3 (i.c. 95% 3,2 a 5,3). No se observó un aumento adicional en la DR después de 5 años. Los márgenes de resección tumoral (R1 versus R0) se asociaron con una DR a 1 año de 3,9 (i.c. del 95% 1,6 a 6,2), y a 3 años de 5,9 (i.c. del 95% 2,6 a 9,3) de riesgo de M-PM en un subanálisis. CONCLUSIÓN: El riesgo global de M-PM en el cáncer colorrectal en pacientes es bajo, pero aumenta en las categorías de estadios T y N avanzados. Puede ser necesario un seguimiento de al menos 3 años después de la cirugía de CCR, dado el tratamiento potencialmente curativo de la M-PM diagnosticada precozmente.

Mucosal and systemic immune modulation by Trichuris trichiura in a self-infected individual.

Helminthic therapy of immune-mediated diseases has gained attention in recent years, but we know little of how helminths modulate human immunity. In this study, we investigated how self-infection with Trichuris (T.) trichiura in an adult man without intestinal disease affected mucosal and systemic immunity. Colonic mucosal biopsies were obtained at baseline, during T. trichiura infection, and after its clearance following mebendazole treatment. Unexpectedly, the volunteer experienced a Campylobacter colitis following T. trichiura clearance, and this served as a positive infectious control. Trichuris trichiura colonization induced equally increased expressions of T-helper (h)1-, Th2-, Th17- and Treg-associated cytokines and transcription factors, measured by quantitative polymerase chain reaction. We observed several indicators of modulation of systemic immunity during the T. trichiura infection. Plasma eosinophils and anti-Trichuris antibodies rose markedly during the inoculation phase, and a shift towards a Th2-dominated T cell response at the expense of the Th1-response was observed in circulating T cells. Taken together, our findings corroborate that helminths modulate regional and systemic human immunity.

A common variation of the PTEN gene is associated with peripheral insulin resistance.

AIM: Phosphatase and tensin homologue (PTEN) reduces insulin sensitivity by inhibiting the phosphatidylinositol 3-kinase (PI3K)/v-akt murine thymoma viral oncogene homologue (Akt) pathway. This study investigated how a common single nucleotide polymorphism near PTEN, previously associated with fasting levels of plasma insulin and glucose, influences in vivo glucose metabolism and insulin signalling. The primary outcome measure was the gene variant's association with peripheral glucose disposal rate and, secondarily, whether this association was explained by altered activities of PTEN targets PI3K and Akt. METHODS: A total of 183 normoglycaemic Danes, including 158 twins and 25 singletons, were genotyped for PTEN rs11202614, which is in complete linkage disequilibrium with rs2142136 and rs10788575, which have also been reported in association with glycaemic traits and type 2 diabetes (T2D). Hepatic and peripheral insulin sensitivity was measured using tracer and euglycaemic-hyperinsulinaemic clamp techniques; insulin secretion was assessed by intravenous glucose tolerance test; and muscle biopsies were taken during insulin infusion from 150 twins for measurement of PI3K and Akt activities. RESULTS: The minor G allele of PTEN rs11202614 was associated with elevated fasting plasma insulin levels and a decreased peripheral glucose disposal rate, but not with the hepatic insulin resistance index or insulin secretion measured as the first-phase insulin response and disposition index. The single nucleotide polymorphism was not associated with either PI3K or Akt activities. CONCLUSION: A common PTEN variation is associated with peripheral insulin resistance and subsequent risk of developing T2D. However, the association with insulin resistance is not explained by decreased proximal insulin signalling in skeletal muscle.

Suboptimal surgery and omission of neoadjuvant therapy for upper rectal cancer is associated with a high risk of local recurrence.

AIM: The aim of the present study was to estimate the risk of local recurrence in an audited cohort of patients, with a particular focus on patients with upper rectal cancer treated by partial mesorectal excision without neoadjuvant therapy. METHOD: Perioperative clinical data on all patients who underwent mesorectal excision for primary adenocarcinoma of the rectum in the period from 2007 to 2010 were prospectively collected and follow-up data on oncological outcome were retrieved from patient records. Three-year actuarial local recurrence rates were estimated using Kaplan-Meier methods. RESULTS: Local recurrence was diagnosed in 17 of 247 patients treated with curative intent. The 3-year actuarial local recurrence rate was 7.0% (95% CI 4.0-11.8). The risk of local recurrence was negatively associated with tumour stage (P = 0.015), an involved circumferential resection margin (P = 0.007) and tumour height (P = 0.044). The local recurrence rate at 3 years was 13.5% after partial mesorectal excision, 2.9% following total mesorectal excision and 5.7% after extralevator abdominoperineal excision (P = 0.032). CONCLUSION: Tumour stage and an involved circumferential resection margin were the most important predictors of local recurrence. For cancer of the upper rectum, partial mesorectal excision was associated with a high risk of local recurrence.

Implementation of complete mesocolic excision at a university hospital in Denmark: An audit of consecutive, prospectively collected colon cancer specimens.

AIM: Over recent years there has been a new focus on the quality of colon cancer surgery following the description and introduction of complete mesocolic excision (CME). In the same period, laparoscopic surgery has been widely applied to the treatment of colon cancer. We aimed to evaluate the introduction of both CME and laparoscopic-assisted surgery at Aarhus University Hospital, Denmark between 2008 and 2011. Secondly we aimed to evaluate the impact on the quality of surgery of post-operative team meetings where pathologists demonstrated the plane of surgery on the specimens. METHOD: A series of 209 consecutive and prospectively collected colon cancer specimens were evaluated by assessing the plane of surgery and measuring the amount of tissue resected. Multivariate analyses were used to control for influencing factors. RESULTS: The proportion of specimens resected in the mesocolic plane was high and increased significantly following the introduction of post-operative team meetings (52%-76%, p = 0.02). Laparoscopic surgery enhanced the distance between the tumour and the arterial tie by a mean of 27 mm (p < 0.0001) and the distance between the nearest bowel wall and the arterial tie by 26 mm (p < 0.0001) when compared to an open approach. Factors such as body mass index and age influenced the outcome for surgical quality. CONCLUSION: Implementation of CME and laparoscopic-assisted surgery for colon cancer is a challenge and requires continuous training and feedback. Post-operative multidisciplinary team meetings may be a key element in this process.

Routine noninvasive prenatal screening for fetal RHD in plasma of RhD-negative pregnant women-2 years of screening experience from Denmark.

OBJECTIVE: Prenatal and postnatal RhD prophylaxis reduces the risk of RhD immunization in pregnancies of RhD-negative women. Based on the result from prenatal screening for the fetal RHD gene, prenatal RhD prophylaxis in Denmark is targeted to RhD-negative women who carry an RhD-positive fetus. Here, we present a 2-year evaluation of a nationwide prenatal RHD screening. METHODS: Blood samples were drawn from RhD-negative women in gestational week 25. DNA was extracted from maternal plasma and analyzed for the RHD gene. The prenatal RHD results were compared with the serological typing of newborns in 12,668 pregnancies. Early compliance was assessed for 690 pregnancies. RESULTS: The sensitivity for the detection of fetal RHD was 99.9% (95% CI: 99.7-99.9%). Unnecessary recommendation of prenatal RhD prophylaxis was avoided in 97.3% of the women carrying an RhD-negative fetus. Fetuses that were seropositive for RhD were not detected in 11 pregnancies (0.087%). The sample uptake percentage was 84.2%, and the compliance for prenatal anti-D administration was 93.2%. CONCLUSION: The high sensitivity, maintained over 2 years, underlines the reliability of routine prenatal fetal RHD screening in RhD-negative pregnant women, specifically at 25 weeks of gestation. The remaining challenges are logistical and are related to program compliance.

Effect of IL-6 on the insulin sensitivity in patients with type 2 diabetes.

Elevated interleukin-6 (IL-6) levels are associated with type 2 diabetes, but its role in glucose metabolism is controversial. We investigated the effect of IL-6 on insulin-stimulated glucose metabolism in type 2 diabetes patients and hypothesized that an acute, moderate IL-6 elevation would increase the insulin-mediated glucose uptake. Men with type 2 diabetes not treated with insulin [n = 9, age 54.9 ± 9.7 (mean ± SD) yr, body mass index 34.8 ± 6.1 kg/m(2), HbA1c 7.0 ± 1.0%] received continuous intravenous infusion with either recombinant human IL-6 (rhIL-6) or placebo. After 1 h with placebo or rhIL-6, a 3-h hyperinsulinemic-isoglycemic clamp was initiated. Whole body glucose metabolism was measured using stable isotope-labeled tracers. Signal transducer and activator of transcription 3 (STAT3) phosphorylation and suppressor of cytokine signaling 3 (SOCS3) expression were measured in muscle biopsies. Whole body energy expenditure was measured using indirect calorimetry. In response to the infusion of rhIL-6, circulating levels of IL-6 (P < 0.001), neutrophils (P < 0.001), and cortisol (P < 0.001) increased while lymphocytes decreased (P < 0.01). However, IL-6 infusion did not change glucose infusion rate, rate of appearance, or rate of disappearance during the clamp. While IL-6 enhanced phosphorylation of STAT3 in skeletal muscle (P = 0.041), the expression of SOCS3 remained unchanged. Whole body oxygen uptake (P < 0.01) and expired carbon dioxide (P < 0.01) increased during rhIL-6 infusion. In summary, although IL-6 induced local and systemic responses, the insulin-stimulated glucose uptake was not affected. While different contributing factors may be involved, our results are in contrast to our hypothesis and previous findings in young, healthy men.

The effect of GWAS identified BMI loci on changes in body weight among middle-aged Danes during a five-year period.

OBJECTIVE: Genome-wide association studies have identified genetic variants associating with BMI, however, it is un-clarified whether the same variants also influence body weight fluctuations. METHODS: Among 3,982 adult individuals that attended both a baseline and a five-year follow-up examination in the Danish Inter99 intervention study, a genetic risk score (GRS) was constructed based on 30 BMI variants to address whether it is associated with body weight changes. Moreover, it was examined whether the effect of lifestyle changes was modulated by the GRS. RESULTS: The GRS associated strongly with baseline body weight, with a per risk allele increase of 0.45 (0.33-0.58) kg (P = 2.7 × 10(-12) ), corresponding to a body weight difference of 3.41 (2.21-4.60) kg comparing the highest (≥ 30 risk alleles) and lowest (≤ 26 risk alleles) risk allele tertile. No association was observed with changes in body weight during the five years. Changes in lifestyle, including physical activity, diet and smoking habits associated strongly with body weight changes, however, no interactions with the GRS was observed. CONCLUSION: The GRS associated with body weight cross-sectionally, but not with changes over a five-year period. Body weight changes were influenced by lifestyle changes, however, independently of the GRS.

Extent and completeness of mesorectal excision evaluated by postoperative magnetic resonance imaging.

BACKGROUND: The major advance in rectal cancer management over the past 20 years has been the standardization of mesorectal excision. The aim of this study was to determine the prevalence and localization of inadvertent residual mesorectum detected on magnetic resonance imaging (MRI) after rectal cancer surgery. METHODS: Postoperative T2-weighted MRI of the pelvis was performed on patients following mesorectal excision. A multidisciplinary team radiologist evaluated the images with regard to residual mesorectum and distal margin. Only mesorectum above the level of the anastomosis perpendicular to the bowel was regarded as inadvertent residual mesorectum after partial mesorectal excision. Histopathological records, standardized photographs and clinical records were assessed. The pathology and MRI findings were evaluated independently in a blinded fashion. RESULTS: MRI-detected residual mesorectum was identified in 54 (39·7 per cent) of 136 patients. There was agreement with the pathology findings in 88 patients (64·7 per cent). Residual mesorectum was more frequent in patients treated with partial mesorectal excision (63 per cent) than those who had total mesorectal excision (36 per cent) or abdominoperineal resection (13 per cent) (P < 0·001). Pathology and MRI findings both showed that the distal resection margin after partial mesorectal excision was less than 5 cm in more than three-quarters of patients, and less than 3 cm in more than one-third. CONCLUSION: Inadvertent residual mesorectum was commonly found on postoperative MRI, especially after partial mesorectal excision.

Plasma follistatin is elevated in patients with type 2 diabetes: relationship to hyperglycemia, hyperinsulinemia, and systemic low-grade inflammation.

BACKGROUND: Plasma follistatin is elevated in patients with low-grade inflammation and insulin resistance as observed with polycystic ovary syndrome. In the present study, we evaluated plasma follistatin in patients with type 2 diabetes characterised by low-grade inflammation and assessed the acute effects of hyperglycemia, hyperinsulinemia and LPS on plasma follistatin. METHODS: Baseline plasma follistatin and inflammatory biomarkers were measured in a cross-sectional study that involved 95 patients with type 2 diabetes and 103 matched controls. To determine the acute effect of hyperglycemia and hyperinsulinemia on follistatin, hyperglycemic and hyperinsulinemic-euglycemic clamps were performed in five healthy males. Furthermore, 15 patients with type 2 diabetes and 22 healthy controls were challenged with low-dose LPS to determine the effect on follistatin. RESULTS: Patients with type 2 diabetes have higher HOMA2-IR values mean [95% CI] 1.64 [1.40-1.93] versus mean 0.86 [0.75-0.99], p < 0.001 and inflammatory markers compared with controls. Baseline plasma follistatin is elevated in patients with type 2 diabetes compared with controls mean 1564 [1456-1680] versus mean 1328 [1225-1440] ng/L, p = 0.003 and correlates with fasting glucose levels (r = 0.44, p < 0.0001), 2 h glucose (r = 0.48, p < 0.0001), HbA1c (r = 0.41, p < 0.0001), triacylglycerol (r = 0.28, p = 0.008) and total cholesterol (r = 0.33, p = 0.004) in patients but not in controls. No correlation exists between plasma follistatin and inflammatory biomarkers in either of the groups. Neither hyperglycemia, hyperinsulinemia nor LPS increase plasma follistatin. CONCLUSIONS: Plasma follistatin is moderately elevated in patients with type 2 diabetes. Our findings suggest that this is not likely caused by hyperglycemia, hyperinsulinemia or systemic low-grade inflammation.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for peritoneal carcinomatosis: the Danish experience.

AIM: Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is a treatment option with curative intent for selected patients with peritoneal carcinomatosis (PC). CRS and HIPEC have been implemented in Denmark at a single centre since 2006. Six years of data on these patients were analysed. METHOD: Patients with PC from colorectal or appendiceal cancer, pseudomyxoma peritonei or malignant peritoneal mesothelioma referred to the single national HIPEC centre were prospectively registered from June 2006 to July 2012. Morbidity, 30-day mortality and long-term survival of patients who underwent CRS and HIPEC were analysed. RESULTS: In total, 80 patients underwent CRS and HIPEC. PC originated from colorectal cancer in 34 patients, pseudomyxoma peritonei in 29, appendiceal cancer in 13 and malignant peritoneal mesothelioma in four patients. Thirty-two patients had one or more complications during the hospital stay. The 30-day mortality rate was 1.3%. The predicted 2-, 3- and 5-year survival was 60%, 47% and 38% in patients with PC from colorectal cancer, and 100%, 93% and 73% in pseudomyxoma peritonei patients. CONCLUSION: CRS and HIPEC is a safe procedure when centralized as in Denmark. Favourable long-term outcome was achieved in selected patients with PC from colorectal cancer and pseudomyxoma peritonei. Short-term and long-term outcomes were comparable to results from international centres.

Effects of short-term high-fat overfeeding on genome-wide DNA methylation in the skeletal muscle of healthy young men.

AIMS/HYPOTHESIS: Energy-dense diets that are high in fat are associated with a risk of metabolic diseases. The underlying molecular mechanisms could involve epigenetics, as recent data show altered DNA methylation of putative type 2 diabetes candidate genes in response to high-fat diets. We examined the effect of a short-term high-fat overfeeding (HFO) diet on genome-wide DNA methylation patterns in human skeletal muscle. METHODS: Skeletal muscle biopsies were obtained from 21 healthy young men after ingestion of a short-term HFO diet and a control diet, in a randomised crossover setting. DNA methylation was measured in 27,578 CpG sites/14,475 genes using Illumina's Infinium Bead Array. Candidate gene expression was determined by quantitative real-time PCR. RESULTS: HFO introduced widespread DNA methylation changes affecting 6,508 genes (45%), with a maximum methylation change of 13.0 percentage points. The HFO-induced methylation changes were only partly and non-significantly reversed after 6-8 weeks. Alterations in DNA methylation levels primarily affected genes involved in inflammation, the reproductive system and cancer. Few gene expression changes were observed and these had poor correlation to DNA methylation. CONCLUSIONS/INTERPRETATION: The genome-wide DNA methylation changes induced by the short-term HFO diet could have implications for our understanding of transient epigenetic regulation in humans and its contribution to the development of metabolic diseases. The slow reversibility suggests a methylation build-up with HFO, which over time may influence gene expression levels.

Effects of erythropoietin administration on cerebral metabolism and exercise capacity in men.

Recombinant human erythropoietin (EPO) increases exercise capacity by stimulating erythropoiesis and subsequently enhancing oxygen delivery to the working muscles. In a large dose, EPO crosses the BBB and may reduce central fatigue and improve cognition. In turn, this would augment exercise capacity independent of erythropoiesis. To test this hypothesis, 15 healthy young men (18-34 years old, 74 + or - 7 kg) received either 3 days of high-dose (30,000 IU/day; n = 7) double-blinded placebo controlled or 3 mo of low-dose (5,000 IU/wk; n = 8) counter-balanced open but controlled administration of EPO. We recorded exercise capacity, transcranial ultrasonography-derived middle cerebral artery blood velocity, and arterial-internal jugular venous concentration differences of glucose and lactate. In addition, cognitive function, ratings of perceived exertion, ventilation, and voluntary activation by transcranial magnetic stimulation-induced twitch force were evaluated. Although EPO in a high dose increased cerebrospinal fluid EPO concentration approximately 20-fold and affected ventilation and cerebral glucose and lactate metabolism (P < 0.05), 3 days of high-dose EPO administration had no effect on cognition, voluntary activation, or exercise capacity, but ratings of perceived exertion increased (P < 0.05). We confirmed that 3 mo of administration of EPO increases exercise capacity, but the improvement could not be accounted for by other mechanisms than enhanced oxygen delivery. In conclusion, EPO does not attenuate central fatigue or change cognitive performance strategy, suggesting that EPO enhances exercise capacity exclusively by increased oxygen delivery to the working muscles.

Differential aetiology and impact of phosphoinositide 3-kinase (PI3K) and Akt signalling in skeletal muscle on in vivo insulin action.

AIMS/HYPOTHESIS: Insulin resistance in skeletal muscle is a key factor in the development of type 2 diabetes and although some studies indicate that this could be partly attributed to reduced content and activity of various proximal and distal insulin signalling molecules, consensus is lacking. We therefore aimed to investigate the regulation of proximal insulin signalling in skeletal muscle and its effect on glucose metabolism in a large non-diabetic population. METHODS: We examined 184 non-diabetic twins with gold-standard techniques including the euglycaemic-hyperinsulinaemic clamp. Insulin signalling was evaluated at three key levels, i.e. the insulin receptor, IRS-1 and V-akt murine thymoma viral oncogene (Akt) levels, employing kinase assays and phospho-specific western blotting. RESULTS: Proximal insulin signalling was not associated with obesity, age or sex. However, birthweight was positively associated with IRS-1-associated phosphoinositide 3-kinase (PI3K; IRS-1-PI3K) activity (p = 0.04); maximal aerobic capacity (VO2(max)), paradoxically, was negatively associated with IRS-1-PI3K (p = 0.02) and Akt2 activity (p = 0.01). Additionally, we found low heritability estimates for most measures of insulin signalling activity. Glucose disposal was positively associated with Akt-308 phosphorylation (p < 0.001) and Akt2 activity (p = 0.05), but not with insulin receptor tyrosine kinase or IRS-1-PI3K activity. CONCLUSIONS/INTERPRETATION: With the exception of birthweight, 'classical' modifiers of insulin action, including genetics, age, sex, obesity and VO2(max) do not seem to mediate their most central effects on whole-body insulin sensitivity through modulation of proximal insulin signalling in skeletal muscle. We also demonstrated an association between Akt activity and in vivo insulin sensitivity, suggesting a role of Akt in control of in vivo insulin resistance and potentially in type 2 diabetes.

Reduced muscle activation during exercise related to brain oxygenation and metabolism in humans.

Maximal exercise may be limited by central fatigue defined as an inability of the central nervous system to fully recruit the involved muscles. This study evaluated whether a reduction in the cerebral oxygen-to-carbohydrate index (OCI) and in the cerebral mitochondrial oxygen tension relate to the ability to generate a maximal voluntary contraction and to the transcranial magnetic stimulated force generation. To determine the role of a reduced OCI and in central fatigue, 16 males performed low intensity, maximal intensity and hypoxic cycling exercise. Exercise fatigue was evaluated by ratings of perceived exertion (RPE), arm maximal voluntary force (MVC), and voluntary activation of elbow flexor muscles assessed with transcranial magnetic stimulation. Low intensity exercise did not produce any indication of central fatigue or marked cerebral metabolic deviations. Exercise in hypoxia (0.10) reduced cerebral oxygen delivery 25% and decreased 11+/-4 mmHg (P<0.001) together with OCI (6.2+/-0.7 to 4.8+/-0.5, P<0.001). RPE increased while MVC and voluntary activation were reduced (P<0.05). During maximal exercise declined 8+/-4 mmHg (P<0.05) and OCI to 3.8+/-0.5 (P<0.001). RPE was 18.5, and MVC and voluntary activation were reduced (P<0.05). We observed no signs of muscular fatigue in the elbow flexors and all control MVCs were similar to resting values. Exhaustive exercise provoked cerebral deoxygenation, metabolic changes and indices of fatigue similar to those observed during exercise in hypoxia indicating that reduced cerebral oxygenation may play a role in the development of central fatigue and may be an exercise capacity limiting factor.