Neuropsychological effects of occupational exposure to polychlorinated biphenyls.

In the context of a health surveillance program for former PCB-exposed workers of a transformer and capacitor recycling company in Germany, their family members, employees of surrounding companies and area residents a broad range of cognitive functions covering attention, executive processing, reasoning, memory and motor performance was examined. The study aimed at identifying potential adverse effects of PCB load on cognitive functions. Detailed analysis of PCB burden of the participants revealed rather high correlations of lower and higher chlorinated as well as dioxin-like PCBs. Nearly one half of the participants exhibited increased burden in all three PCB classes whereas only 33 out of 237 participants did not show any increased PCB burden. Thus, data analysis followed a two-fold strategy: (1) Based on studies providing data on PCB exposure of the German general population the PCB burden of every participant was classified as normal (percentile rank PR <95) or increased (PR ≥95). Increased burden with respect to lower (LPCBs) and higher chlorinated (HPCBs) as well as dioxin-like (dlPCBs) PCBs was assumed if a participant showed at least one congener surpassing the PR95 criterion for the respective congener class and (2) Overall plasma PCB level per congener class was used as measure of PCB load. In a multivariate approach using structural equation modelling and multiple regression analysis we found a significant impact of PCBs on word fluency and sensorimotor processing irrespective of the measure of PCB burden (PR95 criterion or overall plasma level). However, no effect of PCB burden on memory, attention, and cognitive flexibility could be demonstrated. Particularly, an increase of LPCBs was associated with an overall reduction of verbal fluency of letter and semantic word generation as well as word production based on a single or two alternating criteria. In addition, participants with increased burden of LPCBs exhibited a time-on-task effect in terms of a stronger decline of performance with increasing duration of the verbal fluency task. Moreover, we found adverse effects of HPCBs on Aiming and of dlPCBs on Line Tracking. Results are discussed in terms of (1) a decrease of cerebral dopamine (DA) with non-coplanar PCBs resulting in an impact on fronto-striatal cerebral structures subserving verbal fluency and motor processing, (2) a PCB-induced reduction of norepinephrine leading to the time-on-task effect with verbal fluency, and (3) adverse effects of PCBs on dopaminergic receptors in the cerebellum resulting in impaired fine motor function.

Ex vivo reversal of effects of rivaroxaban evaluated using thromboelastometry and thrombin generation assay.

BACKGROUND: In major bleeding events, the new direct oral anticoagulants pose a great challenge for physicians. The aim of the study was to test for ex vivo reversal of the direct oral anticoagulant rivaroxaban with various non-specific reversal agents: prothrombin complex concentrate (PCC), activated prothrombin complex concentrate (aPCC), recombinant activated factor VII (rFVIIa), and fibrinogen concentrate (FI). METHODS: Blood was obtained from healthy volunteers and from patients treated with rivaroxaban. Blood samples from healthy volunteers were spiked with rivaroxaban to test the correlation between rivaroxaban concentration and coagulation tests. Patient blood samples were spiked with various concentrations of the above-mentioned agents and analysed using thromboelastometry and thrombin generation. RESULTS: When added in vitro, rivaroxaban was significantly (P<0.05) correlated with ROTEM® thromboelastometry EXTEM (extrinsic coagulation pathway) clotting time (CT), time to maximal velocity (MaxV-t), and with all measured thrombin generation parameters. In vivo, CT, MaxV-t, lag time, and peak thrombin generation (Cmax) were significantly correlated with rivaroxaban concentrations. Regarding reversal of rivaroxaban, all tested agents significantly (P<0.05) reduced EXTEM CT, but to different extents: rFVIIa by 68%, aPCC by 47%, PCC by 17%, and FI by 9%. Only rFVIIa reversed EXTEM CT to baseline values. Both PCC (+102%) and aPCC (+232%) altered overall thrombin generation (area under the curve) and increased Cmax (+461% for PCC, +87.5% for aPCC). CONCLUSIONS: Thromboelastometry and thrombin generation assays do not favour the same reversal agents for rivaroxaban anticoagulation. Controlled clinical trials are urgently needed to establish doses and clinical efficacy of potential reversal agents. CLINICAL TRIAL REGISTRATION: EudracCT trial no. 213-00474-30.

Menstrual cycle effects on selective attention and its underlying cortical networks.

It was the aim of the present study to investigate menstrual cycle effects on selective attention and its underlying functional cerebral networks. Twenty-one healthy, right-handed, normally cycling women were investigated by means of functional magnetic resonance imaging using a go/no-go paradigm during the menstrual, follicular and luteal phase. On the behavioral level there was a significant interaction between visual half field and cycle phase with reaction times to right-sided compared to left-sided stimuli being faster in the menstrual compared to the follicular phase. These results might argue for a more pronounced functional cerebral asymmetry toward the left hemisphere in selective attention during the menstrual phase with low estradiol and progesterone levels. Functional imaging, however, did not reveal clear-cut menstrual phase-related changes in activation pattern in parallel to these behavioral findings. A functional connectivity analysis identified differences between the menstrual and the luteal phase: During the menstrual phase, left inferior parietal cortex showed a stronger negative correlation with the right middle frontal gyrus while the left medial frontal cortex showed a stronger negative correlation with the left middle frontal gyrus. These results can serve as further evidence of a modulatory effect of steroid hormones on networks of lateralized cognitive functions not only by interhemispheric inhibition but also by affecting intrahemispheric functional connectivity.

Long-term effects of weight loss after bariatric surgery on functional and structural markers of atherosclerosis.

OBJECTIVE: Pronounced weight loss after bariatric surgery was demonstrated to have significant beneficial effects on surrogates of early atherosclerosis. The aim of this prospective examination was to investigate whether these improvements of endothelial function and vascular structure are persistent in the long-term. DESIGN AND METHODS: A total of 52 obese adults were examined before and 5 years after bariatric surgery. Carotid intima media thickness (IMT), brachial flow-mediated dilation (FMD), abdominal fat distribution, and metabolic parameters were determined. Additional 18 months data were available from 27 patients. RESULTS: After 5 years, mean weight loss ± SD of 25% ± 12 in all subjects was accompanied by known improvements in metabolism. Change in IMT was -0.02 mm ± 0.007, whereas FMD improved by +1.5% ± 0.5. In the subgroup IMT decreased by 0.04 mm ± 0.06 within the first 18 months, whereas no significant change was observed between 18 month and 5 years. FMD improved by 3.8% ± 0.6 after 18 months followed by a nonsignificant decrease of -1.4% ± 0.9. CONCLUSIONS: These long-term results demonstrate that bariatric surgery-induced weight loss improves both functional and structural markers of early atherosclerosis providing further evidence for the beneficial effects of weight loss on obesity-associated alterations of the vasculature.

The novel insulin resistance parameters RBP4 and GLP-1 in patients treated with valproic acid: just a sidestep?

Valproic acid (VPA), as one of the most widely prescribed antiepileptic drugs (AED) for many types of epilepsy in adults and children, is associated with weight gain, alteration of adipocytokine homeostasis, insulin resistance and Non-Alcoholic Fatty Liver Disease (NAFLD). Retinol-binding protein 4 (RBP4) and Glucagon-like peptide-1 (GLP-1) are considered as important new targets in modern type 2 diabetes mellitus therapy linked to insulin resistance, NAFLD and visceral obesity acting via peripheral or central mechanisms. We herein demonstrate the lack of an influence of VPA treatment on RBP4 and GLP-1 in otherwise healthy patients. In summary, the absence of any relationship with RBP4 and GLP-1 concentrations does not suggest a role of these novel insulin resistance parameters as potential regulators of glucose and fat metabolism during VPA-therapy.

Influence of airflow intensity on phytase production by solid-state fermentation.

Phytase production by Aspergillus niger F3 by solid state fermentation (SSF) on citrus peel was evaluated at pilot scale under different aeration conditions. The best airflow intensity was 1 VkgM (Lair kg medium(-1) min(-1)), which allowed to produce 65 units of phytases per gram in dry basis (65 Ug(-1) d.b.) as it removed the metabolic heat generated by the microorganism, Agitation did not improve heat removal. Airflow intensity was considered as scale-up criterion. When the airflow intensity was maintained at 1 VkgM for SSF with 2 and 20 kg of medium, the kinetics parameters for biomass and enzyme concentration at the end of fermentation differed by less than 2. The air flow intensity was required to maintain the temperature and cool the SSF and to provide oxygen for microbial growth. Air flow intensity is a key a factor that must be considered when scale-up of SSF is attempted.

Plasminogen activator inhibitor 1 and visceral obesity during pronounced weight loss after bariatric surgery.

BACKGROUND AND AIMS: Elevated plasminogen activator inhibitor 1 (PAI-1) concentrations are a hallmark of obesity and are considered to contribute to the development of cardiovascular disease. As adipose tissue constitutes a major source for PAI-1 in obesity, we investigated the individual contribution of subcutaneous and intra-abdominal fat on PAI-1 concentrations during pronounced weight loss after bariatric surgery. METHODS AND RESULTS: Thirty-seven obese adults were examined before and 18 months after surgery. Abdominal fat distribution was determined by ultrasound, metabolic parameters and plasma PAI-1 levels by standard methods. BMI was reduced by 9.2 ± 4.9 kg/m(2), while total fat mass and visceral fat diameter (VFD) decreased by 20.7 ± 11.9 kg and 4.2 ± 2.3 cm, respectively. Concomitantly, PAI-1 levels diminished by 3.2 ± 5.6 ng/ml (all p ≤ 0.015). Change in PAI-1 levels was correlated with change in VFD (r = 0.441, p = 0.008), but not with subcutaneous fat diameter. In stepwise multiple regression analysis change in VFD was an independent predictor of change in PAI-1 concentrations. When adjusted for age and sex or total fat mass associations between PAI-1 and VFD remained significant. CONCLUSION: We demonstrate that VFD is a major determinant for PAI-1 concentrations during pronounced weight loss after bariatric surgery. Thus, significant reduction of visceral fat mass may contribute to the reduced cardiovascular morbidity and mortality after bariatric surgery by a concomitant decrease in PAI-1 concentrations.

The behavior of kinetic parameters in production of pectinase and xylanase by solid-state fermentation.

Solid-state fermentation (SSF) is defined as the growth of microbes without a free-flowing aqueous phase. The feasibility of using a citrus peel for producing pectinase and xylanase via the SSF process by Aspergillus niger F3 was evaluated in a 2 kg bioreactor. Different aeration conditions were tested to optimize the pectinase and xylanase production. The best air flow intensity was 1 V kg M (volumetric air flow per kilogram of medium), which allowed a sufficient amount of O2 for the microorganism growth producing 265 U/g and 65 U/g pectinases and xylanases, respectively. A mathematical model was applied to determine the different kinetic parameters related to SSF. The specific growth rate and biomass oxygen yield decreased during fermentation, whereas an increase in the maintenance coefficient for the different employed carbon sources was concurrently observed.

Non-alcoholic fatty liver disease (NAFLD), insulin resistance and lipid profile in antiepileptic drug treatment.

PURPOSE: Patients undergoing long-term treatment with valproic acid (VPA) are prone to develop different features of the metabolic syndrome (MS). The aim of the present study was to evaluate the occurrence of non-alcoholic fatty liver disease (NAFLD), insulin resistance (IR) and a pro-atherogenic lipid profile in patients undergoing VPA, carbamazepine (CBZ) and lamotrigine (LTG) monotherapy compared to healthy controls. METHODS: Abdominal ultrasound as well as measurement of serum fasting insulin and glucose, serum lipids and liver function parameters were performed in VPA (n=23), CBZ (n=22) and LTG (n=23) treated non-diabetic and non-obese epileptic patients compared to healthy controls (n=16). RESULTS: Ultrasound measurement demonstrated characteristics of fatty liver disease in 60.9% of VPA, in 22.7% of CBZ, in 8.7% of LTG treated patients and in 12.5% of the healthy controls, with highest level of steatosis seen in VPA treated patients. In addition, patients on VPA monotherapy showed a higher body-mass index (BMI) when compared to LTG treated patients and controls (p

Neural correlates of recovery from acute hemispatial neglect.

PURPOSE: To investigate the neural correlates associated with recovery from acute spatial neglect resulting from right hemispheric stroke. METHODS: Four neglect patients were investigated both behaviourally and by fMRI at an acute (18 +/- 5 days) and at a chronic stage (123 +/- 18 days) post stroke. RESULTS: At the second assessment all patients showed substantial behavioural improvements. These were associated with an increase of neural activity in the right middle frontal gyrus, right inferior parietal cortex, right inferior temporal gyrus/fusiform gyrus, left superior temporal gyrus/angular gyrus and left anterior cingulate gyrus. Decreased neural activity at the second assessment was found in the right parahippocampal gyrus and left fusiform gyrus. CONCLUSIONS: The pattern of neural reorganisation comprises areas of a right hemisphere fronto-parietal attentional network and corresponding left hemisphere areas suggesting a compensatory recruitment of analogous contralesional areas. Interestingly, a more complex pattern of neural changes was observed in the fusiform gyri which have previously been implicated in lateralised directed spatial attention. There was an increase in the right hemisphere and a decrease in the left hemisphere. This pattern of recovery is reminiscent of a "push-pull" pattern previously described for the dorsal parietal cortex by Corbetta et al. (2005) in the recovery from spatial neglect.

Low effectiveness of syndromic treatment services for curable sexually transmitted infections in rural South Africa.

OBJECTIVES: Syndromic sexually transmitted infection (STI) treatment remains a cost-saving HIV prevention intervention in many countries in Africa. We estimate the effectiveness of syndromic treatment for curable STIs in rural KwaZulu-Natal, South Africa, and the trend in STI prevalences before and after the introduction of syndromic treatment in 1995. METHODS: Data were available from various clinical studies, surveys of public and private health providers, the general population and women attending antenatal, family planning and child immunisation clinics in rural northern KwaZulu-Natal between 1987 and 2004. Overall effectiveness was defined as the estimated proportion of the annual number of symptomatic curable STI episodes cured by syndromic treatment based on separate estimates for six curable STI aetiologies by gender. RESULTS: Median overall effectiveness was 13.1% (95% CI 8.9 to 17.8%) of symptomatic curable STI episodes cured. Effectiveness increased to 25.0% (95% CI 17.3 to 33.8%), 47.6% (95% CI 44.5 to 50.8%) or 14.3% (95% CI 9.9 to 19.4%) if 100% treatment seeking, 100% correct treatment provision or 100% cure were assumed, respectively. Time-trends were difficult to assess formally but there was little evidence of decreasing STI prevalences. Including incurable but treatable herpes simplex virus (HSV)-2 ulcers in the effectiveness calculation would halve the proportion of ulcers cured or correctly treated, but this reduction could be entirely countered by including episodic antiviral treatment in the national guidelines. CONCLUSION: Overall effectiveness of syndromic treatment for curable STIs in rural KwaZulu-Natal remains low and there is little evidence of reduced curable STI prevalences. As syndromic treatment is likely to be a cost-saving HIV prevention intervention in South Africa, innovative strategies are urgently needed to increase rates of treatment seeking and correct treatment provision.

Effect of pronounced weight loss on visceral fat, liver steatosis and adiponectin isoforms.

BACKGROUND: Weight loss induced by bariatric surgery is an effective method to reverse obesity and comorbidities. The aim of this prospective weight loss study was to investigate changes of body fat distribution in relation to adiponectin and its isoforms and further to investigate the influence of both body fat distribution and adiponectin on the degree of liver steatosis. DESIGN: Fifteen severely obese female patients (body mass index 43.1 +/- 4.1, mean age 34.5 +/- 8.6 years) were examined before and after surgical treatment. Grading of fatty liver disease and the subcutaneous and visceral fat diameters were determined by abdominal ultrasonography. Metabolic parameters were determined using standard methods; serum total adiponectin and its isoforms were detected by enzyme immuno assay (EIA). RESULTS: Mean weight loss was 28.3 kg, which was mostly due to a loss in fat mass, accompanied by an increase in total adiponectin and the high molecular weight (HMW) adiponectin isoform. Visceral adipose tissue (VAT) diameter was highly correlated with liver steatosis, even more strongly than the parameters of liver function. In addition, liver steatosis correlated negatively with HMW adiponectin and binary logistic regression revealed that changes in fat mass, HMW adiponectin and alanine aminotransferase (ALT) were the best predictors for changes in the degree of hepatic steatosis. CONCLUSIONS: Our results suggest that circulating HMW adiponectin is associated with both VAT and liver steatosis. In summary, the major findings were that the VAT diameter is highly correlated with liver steatosis, even stronger than the parameters of liver function and the association of HMW adiponectin with liver steatosis was better than with total adiponectin.

Alertness-training in neglect: behavioral and imaging results.

PURPOSE: It has been proposed that the right hemisphere alerting network co-activates, either directly or via the brainstem, the spatial attention system in the parietal cortex. The observation that measures of impaired alertness and sustained attention can be used to predict the outcome of neglect might suggest such a relationship, too. The aim of the present study was to investigate the effects of alertness training on hemispatial neglect. METHOD: A three-week computerised alertness training was applied to patients with chronic (> 3 months) stable visuospatial hemineglect. Training effects were investigated both in a single case and in a group of 7 patients by means of neuropsychological tests and functional magnetic resonance imaging (fMRI). RESULTS: After the training, the patients showed a significant improvement in a neglect test battery above any natural fluctuation during a three-week baseline phase. Improvements in the neglect tasks were accompanied by an increase of both right and left hemisphere frontal, anterior cingulate and superior parietal activation, areas known to be associated with both alertness and spatial attention. Four weeks after the end of the training, the patients' neglect test performance had mostly returned to baseline. Despite decreases of activation in some of the initially reactivated areas, increases in neural activity bilaterally in frontal areas, in the right anterior cingulate cortex, the right angular gyrus and in the left temporoparietal cortex remained. An Optokinetic Stimulation Training (OKS) in a control group of another 7 neglect patients led to comparable behavioral results. After the training, however, there was a reactivation mainly in posterior parts of both hemispheres suggesting training specific functional reorganization. CONCLUSION: The limited stability of the behavioral and reactivation results over time demonstrates that a three-week alertness or OKS training alone does not result in long lasting behavioral improvements and stable reactivation patterns in every patient. We rather suggest that combining alertness and spatial attention oriented training procedures might lead to a more stable amelioration of neglect symptoms.

Impact of alertness training on spatial neglect: a behavioural and fMRI study.

The effects of a 3-week computerised alertness training on chronic (>3 months) visuospatial hemineglect were investigated prospectively in seven patients by means of neuropsychological tests and functional magnetic resonance imaging (fMRI). Following the alertness training, the group showed improved alertness and a significant improvement in the performance of a neglect test battery over and above any improvement during a 3-week baseline phase. Improvements in the neglect tasks were accompanied by an increase of right hemisphere neural activity in frontal cortex, anterior cingulate cortex, precuneus, cuneus and angular gyrus. These areas have previously been associated with alertness and spatial attention. A similar pattern of increased neural activity was found for the left hemisphere. Four weeks after the end of the training, the patients' neglect test performance had mostly returned to baseline, while the increases in neural activity bilaterally in frontal areas, in the right anterior cingulate cortex, the right angular gyrus and the left temporoparietal cortex remained. The data show that a 3-week computerised alertness training can improve performance both in alertness and neglect tests and that these behavioural improvements are associated with reactivation in areas associated with alerting and visuospatial attention. The limited stability of these effects over time suggests that a 3-week alertness training alone does not result in long lasting improvements in every patient, but refining the treatment protocol may lead to a more stable amelioration of neglect symptoms.

Spatial attention: more than intrinsic alerting?

It has been proposed that the right hemisphere alerting network co-activates, either directly or via the brainstem, the attention system in the parietal cortex involved in spatial attention. The observation that impaired alertness and sustained attention can predict the outcome of neglect might suggest such a relationship, too. In the present fMRI study, we intended to analyse and compare the functional anatomy of two attentional conditions both involving intrinsic (endogenous) alerting and fixation but differing with respect to the degree of spatially distributed attention by using the same paradigm under two different attentional conditions. In a group of ten participants, both a focused and a distributed visuospatial attention condition evoked similar patterns of activation in dorsolateral prefrontal regions, in the anterior cingulate gyrus, in the superior and inferior parietal cortex as well as in the superior temporal gyrus and in the thalamus. These activation foci were stronger in the right hemisphere under both conditions. After subtraction of the alertness condition with focused spatial attention, distributed spatial attention with stimuli appearing at unpredictable locations within both visual fields induced additional bilateral activations only in the left and right superior parietal cortex and in the right precuneus suggesting that these regions are specific for a more widespread dispersion of spatial attention.

Laparoscopic retroperitoneal lymphadenectomy in the management of low-stage testicular cancer: technique and results.

Retroperitoneal lymph node dissection (RPLND) is still the most sensitive and specific method for detection of lymph node metastases of testicular cancer. Because of its invasiveness and morbidity the acceptance of open RPLND has decreased significantly resulting in a diagnostic deficit. To reduce morbidity and to increase the acceptance of RPLND, laparoscopy has been introduced. Meanwhile, clinical data with long-term follow-ups are available demonstrating the technical feasibility and oncological safety of laparoscopic RPLND. Studies comparing laparoscopy and open surgery could show advantages for the laparoscopic approach concerning blood loss, intraoperative complications and operative time. Antegrade ejaculation can be preserved in the majority of patients. In conclusion, laparoscopic RPLND is a safe method for the management of low-stage germ cell tumors with minimal invasiveness and excellent clinical results. With an increasing number of urologists trained in laparoscopy and an increasing number of published data, it may become a standard approach for low-stage nonseminomatous testicular cancer.

Large-vessel arteritis and myelodysplastic syndrome: report of two cases.

Myelodysplastic syndrome (MDS) is frequently associated with autoimmune diseases such as polymyalgia, arthritis, and rarely, with systemic vasculitis. The pathogenesis of these autoimmune complications remains unknown, but there is increasing evidence of profound immune dysregulation in MDS. In the few cases reported so far, vasculitides associated with MDS affected mainly cutaneous vessels. Here we describe two cases of acute large-vessel vasculitis in association with MDS. The first patient is a 67-yr-old male presenting with a massive large-vessel arteritis as primary manifestation of refractory anemia with excess of blasts type 1 (RAEB-1). The second patient is a 60-yr-old male, who presented with acute thoracic aortitis after a 2-yr history of refractory anemia with ringed sideroblasts (RARS). Both patients received immunosuppressive treatment with steroids, leading to rapid improvement of systemic inflammatory symptoms, vessel wall injury and peripheral blood counts. Whereas the first patient displayed sustained favorable hematologic responses under long-term steroid therapy, there was a rapid transformation into secondary acute myeloid leukemia in the second patient. We conclude that large-vessel vasculitis should be added to the list of potential autoimmune complications in MDS. In this clinical setting, steroid therapy may alleviate inflammatory symptoms and result in beneficial hematologic responses.

Sensitive detection of tumour cells in effusions by combining cytology and fluorescence in situ hybridisation (FISH).

Diagnosis of malignant cells in effusions is important for staging procedures and resulting therapeutic decisions. Cytodiagnostics in effusions is sometimes difficult since reactive mesothelial cells can mimic malignant cells. We used fluorescence in situ hybridisation (FISH) in single-colour or if appropriate in dual-colour evaluation to detect chromosomal aberrations in effusion cells as markers of malignancy, to raise the diagnostic yield. Cytologic and FISH evaluations--by using probes representing several chromosomes always including chromosomes 11 and 17--were performed in 358 effusion fluids. Cytology was positive for malignancy in 44.4% of all effusions, whereas FISH was positive in 53.9% (P=0.0001). The combination of cytology and FISH was diagnostic for malignancy in 60.9% of effusions. Diagnostic superiority of FISH was demonstrated in effusions from breast cancer, lung cancer, pancreatic cancer, and in effusions from the entire group of gynaecological and gastrointestinal carcinomas. In transudates (effusion protein <2.5 g dl(-1)), malignant cells were detectable by cytology, FISH, and combined use of both methods in 18.6, 30, and 37.1% of effusions, respectively, suggesting that cytologic and molecular analysis should be performed also with transudates. In conclusion, FISH in combination with conventional cytology is a highly sensitive and specific diagnostic tool for detecting malignant cells in effusions.

Heart rate response to ultraendurance cycling.

The heart rate (HR) response to ultraendurance cycling is poorly understood. This case report describes the exercise intensity of ultraendurance cycling by means of HR monitoring in a well trained male amateur cyclist performing the Otztal Radmarathon twice en bloque in a circuit of two identical laps (distance 460 km; cumulative altitude difference 11,000 m). The overall intensity was moderate (HR(mean) = 130 beats/min; HR(mean)/HR(max) = 0.71) corresponding to an average individual workload of 47% of VO(2)MAX. Almost the whole race was performed under aerobic conditions (99.6%); high intensity work was negligible (0.4%). The average speed and the HR response also declined in the course of the two laps, average speed by 17.2% (23.8 to 19.7 km/h), HR(mean) by 10.1% (138 to 124 beats/min), and HR(mean)/HR(max) by 10.7% (0.75 to 0.67). This scale of HR decrease corresponds to comparable data gained in the field of triathlon and represents a specific cardiac feature of ultraendurance exercise in general.

Exercise intensity of cycle-touring events.

The aim of the study was to analyze the exercise intensity of recreational cyclists participating in a cycling-touring event. In 14 male healthy recreational cyclists heart rate (HR) monitoring was performed during the Otztal Radmarathon 1999 (distance: 230 km; altitude difference: 5500 m) in order to evaluate the HR response and to estimate the cardiopulmonary strains for the less-trained athlete confronted with such a marathon. Four different exercise intensities were defined as percentages of maximal HR (HR(max)) as follows: recovery HR (HR(re)) < 70 % of HR max; moderate aerobic HR (HR(ma)) = 70 - 80 %; intense aerobic HR (HR(ia)) = 80 - 90 %; and anaerobic HR (HR(an)) > 90 %. All athletes finished the competition successfully. The mean racing time was 10 h 14 min, the average speed 22.5 km/h. The mean HR(max) was 188 bpm, the average value of the measured HRs (HR(average)) was 145 bpm resulting in a mean HR(average)/HR(max) ratio of 0.77. Athletes spent 18.5 % (1 h 54 min) of total race time within HR(re), 28 % (2 h 52 min) within HR(ma), 39.5 % (4 h 02 min) within HR(ia), and 14 % (1 h 26 min) within HR(an). The vast majority of exercise was done under "aerobic conditions" (HR(re) + HR(ma) + HR(ia) = 86 % or 8 h 48 min) - confirming the knowledge that the aerobic energy supply is crucial for the performance of long-term exercise. The large amount of high exercise intensities (HR(ia) + HR(an) = 53.5 % or 5 h 30 min), however, features the intense cardiopulmonary strains evoked by such competitions. The HR response was related to the course profile with HRs significantly declining in all subjects to an extent of 10 % during the course of race. Our findings show that the exercise intensity borne by recreational cyclists during a cycle-touring event is high and very similar to that of professionals. With respect to the high cardiovascular strains a thorough medical screening is advisable for any participant of such an event combining both high volume and high intensity loads.