Inability to work following COVID-19 vaccination-a relevant aspect for future booster vaccinations.

OBJECTIVES: COVID-19 vaccination is a key prevention strategy to reduce the spread and severity of SARS-CoV-2 infections. However, vaccine-related inability to work among healthcare workers (HCWs) could overstrain healthcare systems. STUDY DESIGN: The study presented was conducted as part of the prospective CoVacSer cohort study. METHODS: This study examined sick leave and intake of pro re nata medication after the first, second, and third COVID-19 vaccination in HCWs. Data were collected by using an electronic questionnaire. RESULTS: Among 1704 HCWs enrolled, 595 (34.9%) HCWs were on sick leave following at least one COVID-19 vaccination, leading to a total number of 1550 sick days. Both the absolute sick days and the rate of HCWs on sick leave significantly increased with each subsequent vaccination. Comparing BNT162b2mRNA and mRNA-1273, the difference in sick leave was not significant after the second dose, but mRNA-1273 induced a significantly longer and more frequent sick leave after the third. CONCLUSION: In the light of further COVID-19 infection waves and booster vaccinations, there is a risk of additional staff shortages due to postvaccination inability to work, which could negatively impact the already strained healthcare system and jeopardise patient care. These findings will aid further vaccination campaigns to minimise the impact of staff absences on the healthcare system.

Magnetic Turbulence and Current Drive during Local Helicity Injection.

Magnetic measurements during dc helicity injection tokamak startup indicate Alfvénic turbulence in the injected current streams mediates magnetic relaxation and results in macroscopic plasma current drive. Localization of such activity to the injected current streams, a bias voltage dependence to its onset, and higher-order spectral analysis indicate super-Alfvénic electrons excite instabilities that drive the observed turbulence. Measured fluctuation helicity is consistent with an α-dynamo electromotive force driving net current comparable to the macroscopic equilibrium current density. These results imply new constraints for scaling local helicity injection to larger devices.

Noninductively Driven Tokamak Plasmas at Near-Unity Toroidal Beta.

Access to and characterization of sustained, toroidally confined plasmas with a very high plasma-to-magnetic pressure ratio (ß_{t}), low internal inductance, high elongation, and nonsolenoidal current drive is a central goal of present tokamak plasma research. Stable access to this desirable parameter space is demonstrated in plasmas with ultralow aspect ratio and high elongation. Local helicity injection provides nonsolenoidal sustainment, low internal inductance, and ion heating. Equilibrium analyses indicate ß_{t} up to ∼100% with a minimum |B| well spanning up to ∼50% of the plasma volume.

Gestational diabetes outcome in a single center study: higher BMI in children after six months.

The aim of the study was to examine obstetric outcomes and metabolic disorders in patients with gestational diabetes mellitus (GDM) and their offspring compared to mothers without GDM and their offspring. We performed a retrospective single center cohort study of mothers with GDM using a questionnaire with items concerning the maternal medical history, neonatal complications, and child development. Mothers with gestational diabetes (GDM; n=130) and those with normal glucose tolerance (NGT; n=77) were recruited. GDM mothers were older (37.58 years vs. 34.32 years, p<0.0001) and had a greater body mass index (25.18 kg/m² vs. 23.37 kg/m², p<0.01). There were no significant differences regarding the mean birth weight, the frequency of Cesarean sections, and the prevalence of macrosomia (> 4 000 g). At follow-up (pediatric U5 screening visit after 6 months of birth) children of mothers with GDM had significantly higher BMI than the children of the NGT group (17.07 kg/m² vs. 16.59 kg/m², p=0.042). GDM women in need of insulin therapy during pregnancy had higher BMI than dieting GDM mothers and experienced more frequently an operative vaginal delivery (17.95% vs. 6.17%, OR 3.23, p=0.04). We found less significant differences between GDM mothers with treatment of impaired glucose tolerance and NGT mothers concerning the neonatal outcome than expected. Despite higher BMI of the GDM group's offspring at follow-up U5 visit, the children did not show any other development disorder. In conclusion treatment of GDM could minimize the frequency of obstetric and neonatal complications in this risk group.

Effect of a randomised controlled vitamin D trial on insulin resistance and glucose metabolism in patients with type 2 diabetes mellitus.

The aim of our study was to investigate the influence of a 6-month vitamin D supplementation in patients with noninsulin-requiring type 2 diabetes mellitus. We included 86 patients in a placebo-controlled, randomised, double-blind study. During 6 months patients received Vigantol oil once a week corresponding to a daily dose of 1904 IU or placebo oil, followed by 6 months of follow-up. At start and at 3-month intervals 25OHD, PTH, body mass index, HbA1c, insulin, C-peptide, and homeostasis model assessment-index were measured. The primary outcome was a change in fasting blood glucose and insulin levels. After 6 months of therapy, the verum group's 25OHD had increased to a median of 35 ng/ml in comparison to the placebo group (median 20 ng/ml, p<10-6). PTH tended to decrease in the verum group (25.5 pg/ml vs. 35.0 pg/ml, p=0.08). After 6 months of therapy, 31 patients (78%) achieved a 25OHD concentration of >20 ng/ml. Their HbA1c was significantly lower at baseline (p=0.008) and after therapy (p=0.009) than in patients with 25OHD below 20 ng/ml. C-Peptide, insulin, and HOMA-index did not change significantly in the verum group but fasting insulin was positively correlated with 25OHD concentrations after 6 months of therapy in both groups. There were no significant effects of vitamin D with a daily dose of 1904 IU on metabolic parameters in type 2 diabetes. However, the correlative findings of this study suggest a link of the 25OHD status and metabolic function in type 2 diabetes. Whether vitamin D therapy with higher doses can improve glucose metabolism needs to be investigated in follow-up trials.

Efficacy and safety of once-weekly glucagon-like peptide 1 receptor agonist albiglutide (HARMONY 1 trial): 52-week primary endpoint results from a randomized, double-blind, placebo-controlled trial in patients with type 2 diabetes mellitus not controlled on pioglitazone, with or without metformin.

AIMS: To show that albiglutide, a glucagon-like peptide-1 receptor agonist, is an effective and generally safe treatment to improve glycaemic control in patients with type 2 diabetes mellitus whose hyperglycaemia is inadequately controlled with pioglitazone (with or without metformin). METHODS: In this 3-year, randomized, double-blind, placebo-controlled study, 310 adult patients on a regimen of pioglitazone (with or without metformin) were randomly assigned to receive additional treatment with albiglutide [30 mg subcutaneous (s.c.) once weekly, n = 155] or matching placebo (n = 155). The primary efficacy endpoint was change from baseline to week 52 (intention-to-treat) in glycated haemoglobin (HbA1c). RESULTS: The model-adjusted change from baseline in HbA1c at week 52 was significantly better with albiglutide than with placebo (-0.8%, 95% confidence interval -1.0, -0.6; p < 0.0001). Change from baseline fasting plasma glucose was -1.3 mmol/l in the albiglutide group and +0.4 mmol/l in the placebo group (p < 0.0001); a significantly higher percentage of patients reached the HbA1c goals with albiglutide (p < 0.0001), and the rate of hyperglycaemia rescue up to week 52 for albiglutide was 24.4 versus 47.7% for placebo (p < 0.0001). Albiglutide plus pioglitazone had no impact on weight, and severe hypoglycaemia was observed rarely (n = 2). With few exceptions, the results of safety assessments were similar between the groups, and most adverse events (AEs) were mild or moderate. The 52-week incidence rates for gastrointestinal AEs for albiglutide and placebo were: 31.3 and 29.8%, respectively (diarrhoea: 11.3 and 8.6%; nausea: 10.7 and 11.3%; vomiting: 4.0 and 4.0%). CONCLUSIONS: Albiglutide 30 mg administered once weekly as an add-on to pioglitazone (with or without metformin) provided effective and durable glucose lowering and was generally well tolerated.

Stereotactic ablative radiotherapy for small lung tumors with a moderate dose. Favorable results and low toxicity.

BACKGROUND: Stereotactic ablative body radiotherapy (SBRT, SABR) is being increasingly applied because of its high local efficacy, e.g., for small lung tumors. However, the optimum dosage is still under discussion. Here, we report data on 45 lung lesions [non-small cell lung cancer (NSCLC) or metastases] in 39 patients treated between 2009 and 2010 by SABR. PATIENTS AND METHODS: SABR was performed with total doses of 35 Gy (5 fractions) or 37.5 Gy (3 fractions) prescribed to the 60% isodose line encompassing the planning target volume. Three-monthly follow-up CT scans were supplemented by FDG-PET/CT if clinically indicated. RESULTS: The median follow-up was 17 months. Local progression-free survival rates were 90.5% (all patients), 95.0% (NSCLC), and 81.8% (metastases) at 1 year. At 2 years, the respective local progression-free survival rates were 80.5%, 95.0%, and 59.7%. Overall survival rates were 71.1% (all patients), 65.4% (NSCLC), and 83.3% (metastases) at 1 year. Overall survival rates at 2 years were 52.7%, 45.9%, and 66.7%, respectively. Acute side effects were mild. CONCLUSION: With the moderate dose schedule used, well-tolerated SABR led to favorable local tumor control as in other published series. Standardization in reporting the dose prescription for SABR is needed to allow comparison of different series in order to determine optimum dosage.

Thermoneutrality induces vascular dysfunction and impaired metabolic function in male Wistar rats: a new model of vascular disease.

OBJECTIVE: Cardiovascular disease is of paramount importance, yet there are few relevant rat models to investigate its pathology and explore potential therapeutics. Housing at thermoneutral temperature (30 °C) is being employed to humanize metabolic derangements in rodents. We hypothesized that housing rats in thermoneutral conditions would potentiate a high-fat diet, resulting in diabetes and dysmetabolism, and deleteriously impact vascular function, in comparison to traditional room temperature housing (22 °C). METHODS: Male Wistar rats were housed at either room temperature or thermoneutral temperatures for 16 weeks on either a low or high-fat diet. Glucose and insulin tolerance tests were conducted at the beginning and end of the study. At the study's conclusion, vasoreactivity and mitochondrial respiration of aorta and carotid were conducted. RESULTS: We observed diminished vasodilation in vessels from thermoneutral rats ( P  < 0.05), whereas high-fat diet had no effect. This effect was also observed in endothelium-denuded aorta in thermoneutral rats ( P  < 0.05). Vasoconstriction was significantly elevated in aorta of thermoneutral rats ( P  < 0.05). Diminished nitric oxide synthase activity and nitrotyrosine, and elevated glutathione activity were observed in aorta from rats housed under thermoneutral conditions, indicating a climate of lower nitric oxide and excess reactive oxygen species in aorta. Thermoneutral rat aorta also demonstrated less mitochondrial respiration with lipid substrates compared with the controls ( P  < 0.05). CONCLUSION: Our data support that thermoneutrality causes dysfunctional vasoreactivity, decreased lipid mitochondrial metabolism, and modified cellular signaling. These are critical observations as thermoneutrality is becoming prevalent for translational research models. This new model of vascular dysfunction may be useful for dissection of targetable aspects of cardiovascular disease and is a novel and necessary model of disease.

Experimental evidence for a reduction in electron thermal diffusion due to trapped particles.

New high time resolution measurements of the electron thermal diffusion χ(e) throughout the sawtooth cycle of the Madison Symmetric Torus reversed-field pinch have been made by utilizing the enhanced capabilities of the upgraded multipoint, multipulse Thomson scattering system. These measurements are compared to the χ(e) due to magnetic diffusion predicted by using information from a new high spectral resolution zero-ß nonlinear resistive magnetohydrodynamic simulation performed, for the first time, at the Lundquist number of high current Madison Symmetric Torus plasmas (S≈4×10(6)). Agreement between the measured and predicted values is found only if the reduction in thermal diffusion due to trapped particles is taken into account.

Altered plasma serine and 1-deoxydihydroceramide profiles are associated with diabetic neuropathy in type 2 diabetes and obesity.

Recent studies suggest that the accumulation of atypical, 1-deoxysphingolipids that lack the C1 hydroxyl group may be associated with diabetic neuropathy (DN). We hypothesized that specific plasma 1-deoxysphingolipids associate with DN severity, and that alterations in plasma serine and alanine associate with 1-deoxysphingolipid elevation in patients with type 2 diabetes (T2D). We examined individual 1-deoxysphingolipid species using LC/MS/MS in plasma samples from 75 individuals including lean controls (LC, n = 19), those with obesity (n = 19), obesity with T2D without DN (ob/T2D, n = 18), and obesity with T2D with DN (Ob/T2D/DN, n = 19). We observed a step wise increase in 1-deoxydihydroceramides across these four groups (spearman correlation coefficient r = 0.41, p = 0.0002). Mean total concentrations of 1-deoxydihydroceramides, and most individual 1-deoxydihydroceramide species, were higher in ob/T2D/DN versus LC group (8.939 vs. 5.195 pmol/100 µL for total 1-deoxydihydroceramides p = 0.005). No significant differences in 1-deoxydihydroceramides were observed between the ob/T2D and ob/T2D/DN groups. l-alanine was higher and l-serine lower in ob/T2D/DN versus LC groups (326.2 vs. 248.0 µM, p = 0.0086 and 70.2 vs. 89.8 µM, p = 0.0110), consistent with a potential contribution of these changes to the observed 1-deoxysphingolipids profiles. 1-deoxydihydroceramides correlated inversely with leg intraepidermal nerve fiber density (CC -0.40, p = 0.003). These findings indicate that 1-deoxydihydroceramides may be important biomarkers and/or mediators of DN.

Cyclic changes of vitamin D and PTH are primarily regulated by solar radiation: 5-year analysis of a German (50 degrees N) population.

Cutaneous vitamin D precursor production depends on UV-exposure and is ineffective in most regions above latitudes of 50 degrees in winter. We hypothesized whether the cyclic course of vitamin D levels can be modelled with sunshine duration and would affect parathyroid hormone concentrations, but not calcium in a large patient population. We investigated 13330 blood samples from 6099 in- and out patients for 25(OH)D3, 1,25(OH)2D3, PTH, and total Ca in Frankfurt, Germany over 6.5 years. Vitamin D deficiency [25(OH)D3 <10 ng/ml] was found in 12.23% and vitamin D insufficiency [25(OH)D3 <20 ng/ml] in 40.62% of all the blood samples and more frequently during winter. We observed a significant difference between men and women, children and adults, migrants and local residents. Cycling of the curve was significantly related to Julian day for 25(OH)D3 and parathyroid hormone (PTH), but not for 1,25(OH)2D3 and Ca. The peak concentration of 25(OH)D3 was found at Aug 16th and correlated well with the length of day whereas PTH is inversely related with 25(OH)D (3). Seasonal cycling of 25(OH)D3-levels correlated significantly with Julian Day and inversely with PTH. This tight feed back ensures stable Ca concentrations within narrow limits. We conclude that changes in vitamin D levels are mainly regulated by solar radiation and to a lesser degree by other factors such as nutrition.

Radially scanning magnetic probes to study local helicity injection dynamics.

Two new magnetic probes have been deployed on the Pegasus spherical tokamak to study the dynamics of local helicity injection non-solenoidal plasma start-up and current drive. The magnetic radial array probe consists of 15 pickup coils (∼5 × 8 mm each) that measure B ̇ z ( R ) over a 15 cm linear extent. The coils consist of traces embedded in a printed circuit board. Three coil designs are utilized to balance frequency response and coil sensitivity. Helmholtz coil measurements are used to measure coil and full assembly bandwidths (∼2 MHz and ∼200 kHz, respectively) and sensitivities (0.18/0.35/0.96 mV T-1 s). The magnetic radial scanning probe is an array of Hall effect sensors that measure field strength ( | B | ≤ 177 mT) and direction at 8 spatial points (ΔR = 1.5 cm), supporting the studies of equilibrium field structure and low-frequency (≤5 kHz) current dynamics. It uses commercial surface-mount Hall effect sensors with chip-integrated amplifiers and compensators that are mounted in a 3-D printed frame. Helmholtz coil measurements indicate negligible cross-field gain nonlinearity and provide absolute calibration of the diagnostic. Both probes are constructed as an electrostatically shielded insertable air-side assembly that mounts within a radially translatable ultrahigh vacuum assembly from an existing probe.

Sepiapterin Improves Vascular Reactivity and Insulin-Stimulated Glucose in Wistar Rats.

In the vasculature, sedentary behavior leads to endothelial abnormalities, resulting in elevated cardiovascular disease risk. Endothelial nitric oxide synthase (eNOS) aberrations characterize endothelial dysfunction; eNOS also regulates mitochondrial function. We hypothesized that sepiapterin (a precursor to eNOS cofactor tetrahydrobiopterin (BH4)) supplementation would improve endothelium-dependent vascular relaxation in sedentary animals via modulation of NOS function and mitochondrial activity. Sedentary male Wistar rats were fed ad libitum for a total of 10 weeks. Sepiapterin was administered in diet during the final 5 weeks. Intraperitoneal insulin and glucose tolerance tests (IP-ITT/IP-GTT) were conducted at baseline and endpoint. Aorta was assessed for vasoreactivity and mitochondrial respiration. Insulin tolerance, determined by IP-ITT, significantly improved in rats treated with sepiapterin (p < 0.05, interaction of time and treatment). Acetylcholine- (ACh-) driven vasodilation was significantly greater in aorta from sepiapterin-treated rats as compared with control (76.4% versus 54.9% of phenylephrine contraction at 20 µM ACh, p < 0.05). Sepiapterin treatment resulted in significantly elevated state 3 (9.00 oxygen pmol/sec∗mg versus 8.17 oxygen pmol/sec∗mg, p < 0.05) and 4 (7.28 oxygen pmol/sec∗mg versus 5.86 oxygen pmol/sec∗mg, p < 0.05) aortic mitochondrial respiration with significantly lower respiratory control ratio (p < 0.05) during octanoylcarnitine-driven respiration. Vasodilation and insulin sensitivity were improved through targeting NOS via sepiapterin supplementation.

CREB activation induces adipogenesis in 3T3-L1 cells.

Obesity is the result of numerous, interacting behavioral, physiological, and biochemical factors. One increasingly important factor is the generation of additional fat cells, or adipocytes, in response to excess feeding and/or large increases in body fat composition. The generation of new adipocytes is controlled by several "adipocyte-specific" transcription factors that regulate preadipocyte proliferation and adipogenesis. Generally these adipocyte-specific factors are expressed only following the induction of adipogenesis. The transcription factor(s) that are involved in initiating adipocyte differentiation have not been identified. Here we demonstrate that the transcription factor, CREB, is constitutively expressed in preadipocytes and throughout the differentiation process and that CREB is stimulated by conventional differentiation-inducing agents such as insulin, dexamethasone, and dibutyryl cAMP. Stably transfected 3T3-L1 preadipocytes were generated in which we could induce the expression of either a constitutively active CREB (VP16-CREB) or a dominant-negative CREB (KCREB). Inducible expression of VP16-CREB alone was sufficient to initiate adipogenesis as determined by triacylglycerol storage, cell morphology, and the expression of two adipocyte marker genes, peroxisome proliferator activated receptor gamma 2, and fatty acid binding protein. Alternatively, KCREB alone blocked adipogenesis in cells treated with conventional differentiation-inducing agents. These data indicate that activation of CREB was necessary and sufficient to induce adipogenesis. Finally, CREB was shown to bind to putative CRE sequences in the promoters of several adipocyte-specific genes. These data firmly establish CREB as a primary regulator of adipogenesis and suggest that CREB may play similar roles in other cells and tissues.

Functional interactions of phosphatidylinositol 3-kinase with GTPase-activating protein in 3T3-L1 adipocytes.

The role of phosphatidylinositol (PI) 3-kinase in specific aspects of insulin signaling was explored in 3T3-L1 adipocytes. Inhibition of PI 3-kinase activity by LY294002 or wortmannin significantly enhanced basal and insulin-stimulated GTPase-activating protein (GAP) activity in 3T3-L1 adipocytes. Furthermore, removal of the inhibitory influence of PI 3-kinase on GAP resulted in dose-dependent decreases in the ability of insulin to stimulate p21ras. This effect was specific to adipocytes, as inhibition of PI 3-kinase did not influence GAP in either 3T3-L1 fibroblasts, Rat-1 fibroblasts, or CHO cells. Immunodepletion of either of the two subunits of the PI 3-kinase (p85 or p110) yielded similar activation of GAP, suggesting that catalytic activity of p110 plays an important role in controlling GAP activity in 3T3-L1 adipocytes. Inhibition of PI 3-kinase activity in 3T3-L1 adipocytes resulted in abrogation of insulin-stimulated glucose uptake and thymidine incorporation. In contrast, effects of insulin on glycogen synthase and mitogen-activated protein kinase activity were inhibited only at higher concentrations of LY294002. It appears that in adipocytes, P1 3-kinase prevents activation of GAP. Inhibition of PI 3-kinase activity or immunodepletion of either one of its subunits results in activation of GAP and decreases in GTP loading of p21ras.

Relapsing pheochromocytoma in a Chinese women caused by a novel mutation in exon 6 of the SDHB gene: a case report.

Pheochromocytomas are rare catecholamine-secreting, chromaffin tumors of the autonomic nervous system. Most pheochromocytomas are sporadic, but up to 24% of pheochromocytomas are part of a familial disorder. Here we describe a female patient, who presented to our outpatient clinic 18 years after removal of a pheochromocytoma of the left adrenal gland in China. Now she reported flank pain on the left side and elevated blood pressure. 24-hour urinary catecholamines, metanephrines, and normetanephrines as well as plasma-norepinephrine were elevated. The transabdominal ultrasonography revealed a tumor with reduced echogenicity in the left suprarenal region, which was suspected to be a recurrent pheochromocytoma. This finding was confirmed by MRT and J (123)-MIBG-scan. Parathyroid hormone (PTH) and calcitonin were in the normal range. After surgical excision, histological examination of the adrenal mass proved to be a pheochromocytoma. Molecular genetic analysis with sequencing of the succinate dehydrogenase type B (SDHB) gene revealed a formerly unknown mutation of codon 214 (CAG-->TAG) leading to an amino acid change of glutamine to a stop-Codon (Q214X-mutation) in exon 6. This case report highlights the necessity of re-evaluating patients with nonsyndromic pheochromocytoma who are diagnosed without genetic testing to estimate the risk of a relapse and to initiate testing of first-degree relatives.

Control and automation of the Pegasus multi-point Thomson scattering system.

A new control system for the Pegasus Thomson scattering diagnostic has recently been deployed to automate the laser operation, data collection process, and interface with the system-wide Pegasus control code. Automation has been extended to areas outside of data collection, such as manipulation of beamline cameras and remotely controlled turning mirror actuators to enable intra-shot beam alignment. Additionally, the system has been upgraded with a set of fast (∼1 ms) mechanical shutters to mitigate contamination from background light. Modification and automation of the Thomson system have improved both data quality and diagnostic reliability.

A novel, cost-effective, multi-point Thomson scattering system on the Pegasus Toroidal Experiment (invited).

A novel, cost-effective, multi-point Thomson scattering system has been designed, implemented, and operated on the Pegasus Toroidal Experiment. Leveraging advances in Nd:YAG lasers, high-efficiency volume phase holographic transmission gratings, and increased quantum-efficiency Generation 3 image-intensified charge coupled device (ICCD) cameras, the system provides Thomson spectra at eight spatial locations for a single grating/camera pair. The on-board digitization of the ICCD camera enables easy modular expansion, evidenced by recent extension from 4 to 12 plasma/background spatial location pairs. Stray light is rejected using time-of-flight methods suited to gated ICCDs, and background light is blocked during detector readout by a fast shutter. This ∼103 reduction in background light enables further expansion to up to 24 spatial locations. The implementation now provides single-shot Te(R) for ne > 5 × 1018 m-3.

Effects of exercise training on oxygen uptake kinetic responses in women with type 2 diabetes.

OBJECTIVE: Women with uncomplicated type 2 diabetes have both a decreased maximal oxygen consumption (VO2max) and slowed oxygen uptake (VO2) kinetics at the onset of exercise compared with nondiabetic women. These abnormalities are seen not only at maximal workloads, but also at the onset of low-level exercise. To evaluate the hypothesis that VO2max and VO2 kinetics would improve with exercise training in untrained people with type 2 diabetes, we measured these parameters in premenopausal sedentary women before and after 3 months of supervised exercise training. RESEARCH DESIGN AND METHODS: A total of 8 women with type 2 diabetes, 9 overweight nondiabetic women, and 10 lean nondiabetic women were studied. At baseline and after 3 months of exercise training, subjects underwent bicycle ergometer testing to obtain VO2max and VO2 kinetics data. RESULTS: On entry, women with type 2 diabetes had the lowest VO2max and slowest VO2 kinetics of the three groups. After exercise training, the women with type 2 diabetes improved their VO2max more than the lean and overweight control women: 28 vs. 5 and 8%, respectively (P < 0.05 for the diabetic group vs. both control groups). In the group with diabetes, VO2 kinetics improved by 39 and 22% at 20 and 30 W, respectively. For the control subjects, VO2 kinetics did not improve at any workload in either group. CONCLUSIONS: Despite beginning with the lowest VO2max and slowest VO2 kinetics, subjects with type 2 diabetes benefited more from an exercise training program than did control subjects. These findings suggest that in addition to its known metabolic effects, exercise training in individuals with type 2 diabetes may be an effective therapy to improve the cardiovascular response to exercise and to overcome low-level exercise impairment as reflected by improved VO2max and VO2 kinetics. If the ability to make circulatory adjustments at the beginning of exercise at low workloads is improved by an exercise training program, as suggested by the VO2 kinetics data, the clinical significance of exercise for people with type 2 diabetes is clear.

Type 2 diabetes exaggerates exercise effort and impairs exercise performance in older women.

OBJECTIVE: Type 2 diabetes mellitus (T2DM) is associated with high levels of disability and mortality. Regular exercise prevents premature disability and mortality, but people with T2DM are generally sedentary for reasons that are not fully established. We previously observed that premenopausal women with T2DM report greater effort during exercise than their counterparts without diabetes, as measured by the Rating of Perceived Exertion (RPE) scale. We hypothesized that RPE is greater in older women with T2DM versus no T2DM. RESEARCH DESIGN AND METHODS: We enrolled overweight, sedentary women aged 50-75 years with (n=26) or without T2DM (n=28). Participants performed submaximal cycle ergometer exercise at 30 W and 35% of individually-measured peak oxygen consumption (35% VO2peak). We assessed exercise effort by RPE (self-report) and plasma lactate concentration. RESULTS: VO2peak was lower in T2DM versus controls (p=0.003). RPE was not significantly greater in T2DM versus controls (30 W: Control, 10.4±3.2, T2DM, 11.7±2.3, p=0.08; 35% VO2peak: Control, 11.1±0.5, T2DM, 12.1±0.5, p=0.21). However, lactate was greater in T2DM versus controls (p=0.004 at 30 W; p<0.05 at 35% VO2peak). Greater RPE was associated with higher lactate, higher heart rate, and a hypertension diagnosis (p<0.05 at 30 W and 35% VO2peak). CONCLUSIONS: Taken together, physiological measures of exercise effort were greater in older women with T2DM than controls. Exercise effort is a modifiable and thereby targetable end point. In order to facilitate regular exercise, methods to reduce exercise effort in T2DM should be sought. TRIAL NUMBER: NCT00785005.