Coherent beam combining of high power quasi continuous wave tapered amplifiers.

We demonstrate coherent beam combining of four high brightness tapered amplifiers in pulsed, quasi continuous wave (QCW) operation, seeded by a 976 nm laser diode. The maximum power of 22.7 W was achieved with > 64% combining efficiency in a close to diffraction limited beam. We discuss turn-on dynamics of tapered amplifiers operated in pulsed mode in detail.

Magnetic moments of chromium-doped gold clusters: the Anderson impurity model in finite systems.

The magnetic moment of a single impurity atom in a finite free electron gas is studied in a combined x-ray magnetic circular dichroism spectroscopy, charge transfer multiplet calculation, and density functional theory study of size-selected free chromium-doped gold clusters. The observed size dependence of the local magnetic moment can be understood as a transition from a local moment to a mixed valence regime. This shows that the Anderson impurity model essentially describes finite systems even though the discrete density of states introduces a significant deviation from a bulk metal, and the free electron gas is only formed by less than 10 electrons. Electronic shell closure in the gold host minimizes the interaction of localized impurity states with the confined free electron gas and preserves the magnetic moment of 5 µ_{B} fully in CrAu_{2}^{+} and almost fully in CrAu_{6}^{+}. Even for open-shell species, large local moments are observed that scale with the energy gap of the gold cluster. This indicates that an energy gap in the free electron gas stabilizes the local magnetic moment of the impurity atom.

Insulin degludec improves long-term glycaemic control similarly to insulin glargine but with fewer hypoglycaemic episodes in patients with advanced type 2 diabetes on basal-bolus insulin therapy.

The aim of the present study was to compare the long-term safety and efficacy of insulin degludec with those of insulin glargine in patients with advanced type 2 diabetes (T2D) over 78 weeks (the 52-week main trial and a 26-week extension). Patients were randomized to once-daily insulin degludec or insulin glargine, with mealtime insulin aspart ± metformin ± pioglitazone, and titrated to pre-breakfast plasma glucose values of 3.9-4.9 mmol/l (70-88 mg/dl). After 78 weeks, the overall rate of hypoglycaemia was 24% lower (p = 0.011) and the rate of nocturnal hypoglycaemia was 31% lower (p = 0.016) with insulin degludec in the extension trial set, while both groups of patients achieved similar glycaemic control. Rates of adverse events and total insulin doses were similar for both groups in the safety analysis set. During 18 months of treatment, insulin degludec + mealtime insulin aspart ± oral antidiabetic drugs in patients with T2D improves glycaemic control similarly, but confers lower risks of overall and nocturnal hypoglycaemia than with insulin glargine treatment.

Insulin degludec results in lower rates of nocturnal hypoglycaemia and fasting plasma glucose vs. insulin glargine: A meta-analysis of seven clinical trials.

BACKGROUND AND AIMS: Basal insulin analogues have a reduced risk of hypoglycaemia compared with NPH insulin, but hypoglycaemia still remains a major impediment to achieving recommended fasting plasma glucose (FPG) targets in patients with diabetes. Insulin degludec (IDeg) is a new basal insulin that forms soluble multihexamers after subcutaneous injection resulting in an ultra-long duration of action and stable glucose-lowering effect. The aim of this analysis was to compare the effect of IDeg on FPG and nocturnal confirmed hypoglycaemia as compared to insulin glargine (IGlar). METHODS AND RESULTS: Data were included from seven phase 3a, randomised, open-label, treat-to-target clinical trials in which once-daily IDeg was compared with once-daily IGlar. Two trials included a total of 957 patients with type 1 diabetes (T1D) and five trials included a total of 3360 patients with type 2 diabetes (T2D); all trials were 26 or 52 weeks in duration. Confirmed hypoglycaemia was defined as plasma glucose <3.1 mmol/L or severe episodes requiring assistance, and nocturnal hypoglycaemia occurred between 00:01 and 05:59. In all trials, the mean end-of-trial FPG was lower for IDeg than IGlar, reaching statistical significance in three trials. Similarly, IDeg was associated with a lower rate of nocturnal confirmed hypoglycaemia vs. IGlar, which was statistically significant in three trials, regardless of type of diabetes or background therapy. CONCLUSION: This analysis shows that the lower rate of nocturnal confirmed hypoglycaemia seen with IDeg relative to IGlar is accompanied by a reduced mean FPG, in particular in patients with T2D.

Efficacy and safety of insulin degludec given as part of basal-bolus treatment with mealtime insulin aspart in type 1 diabetes: a 26-week randomized, open-label, treat-to-target non-inferiority trial.

AIMS: The efficacy and safety of insulin degludec (IDeg) was compared with insulin detemir (IDet), both administered once daily (OD) as basal treatment in participants with type 1 diabetes mellitus (T1DM). The primary outcome was non-inferiority of IDeg to IDet in glycated haemoglobin (HbA1c) reduction after 26 weeks. METHODS: This multinational, 26-week, controlled, open-label, parallel-group trial randomized adults with T1DM to IDeg or IDet as OD basal insulin treatment combined with mealtime bolus insulin aspart (IAsp). Participants with T1DM treated with any basal-bolus insulin regimen for ≥ 12 months prior to the trial, a mean HbA1c ≤ 10.0% (85.8 mmol/mol) and body mass index (BMI) ≤ 35.0 kg/m(2) at screening participated in the trial (IDeg: N = 302; IDet: N = 153). RESULTS: After 26 weeks, HbA1c decreased 0.73% (8.0 mmol/mol) (IDeg) and 0.65% (7.1 mmol/mol) (IDet) [estimated treatment difference (ETD) IDeg-IDet: -0.09% (-0.23; 0.05)95% CI (-10.0 mmol/mol [-2.6; 0.6]95% CI ); confirming non-inferiority]. Mean fasting plasma glucose improved in both groups, and was lower with IDeg than IDet [ETD IDeg-IDet: -1.66 mmol/l (-2.37; -0.95)95% CI , p < 0.0001]. The rate of confirmed hypoglycaemia was similar with IDeg and IDet [45.83 vs. 45.69 episodes per patient-year of exposure (PYE); estimated rate ratio (RR) IDeg/IDet: 0.98 (0.80; 1.20)95% CI , p = 0.86]. The rate of nocturnal confirmed hypoglycaemia was lower with IDeg than IDet [4.14 vs. 5.93 episodes per PYE; RR IDeg/IDet: 0.66 (0.49; 0.88)95% CI , p = 0.0049]. Adverse event profiles were similar between groups. CONCLUSION: IDeg administered OD in basal-bolus therapy effectively improved long-term glycaemic control in participants with T1DM with a lower risk of nocturnal confirmed hypoglycaemia than IDet.

Bubbles in live-stranded dolphins.

Bubbles in supersaturated tissues and blood occur in beaked whales stranded near sonar exercises, and post-mortem in dolphins bycaught at depth and then hauled to the surface. To evaluate live dolphins for bubbles, liver, kidneys, eyes and blubber-muscle interface of live-stranded and capture-release dolphins were scanned with B-mode ultrasound. Gas was identified in kidneys of 21 of 22 live-stranded dolphins and in the hepatic portal vasculature of 2 of 22. Nine then died or were euthanized and bubble presence corroborated by computer tomography and necropsy, 13 were released of which all but two did not re-strand. Bubbles were not detected in 20 live wild dolphins examined during health assessments in shallow water. Off-gassing of supersaturated blood and tissues was the most probable origin for the gas bubbles. In contrast to marine mammals repeatedly diving in the wild, stranded animals are unable to recompress by diving, and thus may retain bubbles. Since the majority of beached dolphins released did not re-strand it also suggests that minor bubble formation is tolerated and will not lead to clinically significant decompression sickness.

Spin coupling and orbital angular momentum quenching in free iron clusters.

Magnetic spin and orbital moments of size-selected free iron cluster ions Fe{n}{+} (n=3-20) have been determined via x-ray magnetic circular dichroism spectroscopy. Iron atoms within the clusters exhibit ferromagnetic coupling except for Fe{13}{+}, where the central atom is coupled antiferromagnetically to the atoms in the surrounding shell. Even in very small clusters, the orbital magnetic moment is strongly quenched and reduced to 5%-25% of its atomic value while the spin magnetic moment remains at 60%-90%. This demonstrates that the formation of bonds quenches orbital angular momenta in homonuclear iron clusters already for coordination numbers much smaller than those of the bulk.

[Novel uses of afterbirth tissues in regenerative medicine]. / Neue Verwendungsmöglichkeiten von Nachgeburtsgewebe für die Regenerative Medizin.

INTRODUCTION: Afterbirth tissues, which include the umbilical cord, placenta, amnion, and cord blood, are usually discarded. Recent progress in regenerative medicine suggests that we re-evaluate these tissues and assess their therapeutic potential. METHODS: Firstly the unique properties of afterbirth tissues and their current use in regenerative medicine are summarised. Then we introduce the cooperation of our institutions and our experiences regarding the collection and utilisation of afterbirth tissues. RESULTS: A literature survey suggests that besides the well-known transplantation of hematopoietic stem cells from cord blood, afterbirth tissues were also used as a source of stem cells, progenitor cells, differentiated cells, and blood vessels for tissue engineering purposes. According to our own experience, the two participating OB/GYN departments and the blood donation service were able to organise a sufficient supply of umbilical cords for research purposes. The yield correlated with incentives for the midwives. A total of more than 4,300 cords was collected for experiments designed to create small caliber vessel grafts. The contamination rate was low. Birth mode significantly affected umbilical vein function, whereas ischaemia for up to 40 h did not have any deleterious effects. Umbilical veins were cryopreserved with a moderate loss of function. Fresh umbilical veins were endothelium-denuded and reseeded with endothelial cells harvested from coronary artery disease patients to generate an autologous surface. CONCLUSIONS: Afterbirth tissues have unique properties which make them ideally suited for regenerative medicine. These tissues can be procured and utilised in research facilities even in the absence of an in-house birthing centre.

Ultrastructure of human placental tissue after 6 h of normoxic and hypoxic dual in vitro placental perfusion.

The dual in vitro perfusion model of human placental tissue allows the study of different aspects of placental function, such as metabolism, transport and secretion of proteohormones, cytokines and prostaglandins. The integrity of the perfused placental tissue is an important parameter to validate the perfusion system. Using light and electron microscopy, the morphology of villous tissue was examined before and after six hours of normoxic (n=10) vs. hypoxic (n=10) perfusion. An apical shift of the rough endoplasmic reticulum and occasional vacuoles were found in the syncytiotrophoblast of the terminal villi, the exchange area of the placenta. No unexpected pathological findings were seen before the perfusion experiments and only slight changes with moderate distension of the endoplasmic reticulum after 6 h of normoxic perfusion. After hypoxic perfusions, distinct ultrastructural alterations, such as oedematous villous stroma, swollen or completely destroyed cell organelles (e.g., mitochondria and endoplasmic reticulum), multiple vacuoles inside syncytio- and cytotrophoblasts as well as the microvilli were seen, which leads to an impairment of the placental barrier and other functions. The ultrastructural examination of placental tissue before and after dual in vitro perfusion broadens the knowledge of physiological and pathophysiological processes in the perfused placenta and may be a beneficial part of regular validation.

[Intravitreal bevacizumab for recurring choroidal neovascularisation]. / Intravitreales Bevacizumab bei rezidivierender idiopathischer chorioidaler Neovaskularisation.

We administered bevacizumab intravitreally to treat a recurrence of CNV after confocal laser coagulation and photodynamic therapy in a 32-year-old female patient with a single functional eye. Before and after treatment the vision in the affected eye was stable at 1.0. Before administration of the VEGF antibody leakage was distinctly seen on fluorescein angiography, which did not appear on examination after the treatment. Despite the entailed measure of risk we decided in favour of intravitreal application because it seemed promising in view of earlier positive clinical experience with it in exsudative AMD and macular oedema following central retinal vein occlusion. Intravitreal bevacizumab is an alternative that should also be considered for the treatment of idiopathic CNV. Careful clinical studies will follow.

Cloning, cellular distribution and functional expression of small intestinal epithelium guinea pig ClC-5 chloride channel.

We report the cloning of a guinea pig ClC-5 chloride channel (gpClC-5) from distal small intestinal epithelial cells by RT-PCR and RACE. The transcript is shown to be present in duodenum, jejunum and ileum epithelium by RT-PCR and Northern analysis. This is confirmed by in situ hybridisation which also shows the transcript to be homogeneously distributed in the crypt and villus regions. Expression of gpClC-5 in HEK-293 cells generated markedly outwardly rectified chloride currents with a perm-selectivity sequence of NO(3)(-)>Cl(-)>Br(-)>I(-)>F(-)>gluconate(-). The possible role of gpClC-5 in this epithelial location is discussed.

Paradoxical pressor effects of beta-blockers in standing elderly patients with mild hypertension: a beneficial side effect.

BACKGROUND: Baroreflex sensitivity declines with age, creating a fall in systolic blood pressure and pulse pressure when standing. If, in addition, blood pressure is reduced as a result of antihypertensive medication, compensatory mechanisms may be inadequate and orthostatic problems may occur. This may be less true in patients on beta-blockers. beta-blockers cause pressor effects in standing patients with autonomic neuropathy, but their effects on standing pulse pressures in elderly subjects with mild hypertension have not been systematically studied. METHODS AND RESULTS: We studied 3741 patients with mild hypertension for 6 months who were being treated with the beta-blocker nebivolol 5 mg daily. Blood pressures were measured after 10 minutes in the supine position and after 1 minute in the standing position. Overall, systolic and diastolic blood pressures rose slightly while standing, whereas pulse pressures remained unchanged. When previously untreated patients (n=2085) >60 and <60 years of age were assessed separately, supine pulse pressures were consistently higher in the elderly group compared with those of the younger subjects by 6 to 11 mm Hg (P<0.001 to 0.0001). However, while standing, pulse pressures rose in the younger subjects, whereas they tended to fall in the elderly group. After 6 months of beta-blockade, this pattern was unchanged in the younger subjects but reversed into significant rise of pulse pressures in the elderly group by 4 (SD 1) mm Hg (P<0.001). In the patients previously treated with other classes of antihypertensive drugs (n=712), the effects were essentially the same. CONCLUSIONS: In elderly patients with mild hypertension, a depressor trend of pulse pressure while standing can be turned into a significant pressor response by treatment with a beta-blocker.

Improvement of diagnosis in the non-invasive assessment of coronary artery disease: enhanced evaluation of quantitative exercise 201thallium imaging by multivariate analysis.

STUDY OBJECTIVE: The aim was to evaluate discriminant analysis, performed in patients without prior myocardial infarction, in enhancing the diagnostic value of quantitative exercise 201thallium scintigraphy. DESIGN: All clinical, electrocardiographic, and scintigraphic variables were first subjected to a univariate analysis. Afterwards a discriminant analysis was done. PATIENTS: 135 patients (104 male) were studied. Age was 24-70 years, mean 55 years. MEASUREMENTS AND MAIN RESULTS: Two discriminant analyses were done. In the first analysis, the ability to detect the presence of coronary artery disease was tested. Significant variables were: (1) history of angina, (2) sex, (3) quantitative analysis of 201thallium scintigraphy, (4) age, (5) ischaemic ST response, (6) angina during the test, and (7) the pressure-rate product. The sensitivity, specificity, and accuracy of classification using the discriminant function were 91%, 87%, and 90%, respectively. The sensitivity was higher than when using only visual interpretation (sensitivity 70%; p less than 0.0002) or quantitative interpretation (sensitivity = 66%; p less than 0.0001) of thallium scans, without significant loss of specificity (p less than 0.5488; p less than 0.6875). In the second analysis, a discriminant function was calculated to detect multivessel disease. Five input variables were selected: (1) number of vessels with stenosis predicted by quantitative analysis, (2) number of vessels with stenosis predicted by visual analysis, (3) ischaemic ST response, (4) sex, (5) angina during the test. Multivariate analysis showed an increase in sensitivity when compared with visual interpretation (78% v 55%; p less than 0.0043) and quantitative analysis (66%; p less than 0.0156). Using the classification, the discriminant function was more accurate than visual analysis (81% v 69%) or quantitative analysis (77%). CONCLUSIONS: The results show that multivariate analysis of non-invasive test results in quantitative thallium exercise testing allows convenient use for clinical purposes with improved results.

Voltage control of calcium transients elicited by caffeine and tetracaine in cultured rat muscle cells.

Cultured hind limb skeletal muscle cells from newborn rats were used to study the effect of caffeine and tetracaine upon intracellular Ca2+ release under voltage or current clamp conditions. Free [Ca2+]i was measured using the fluorescent calcium-sensitive dye Fluo-3. A field containing one or several myotubes was observed with a video camera and image analysis of fluorescence changes was performed. Addition of 100-500 microM tetracaine to the external saline elicited strong fluorescence responses in non-clamped cells, but significantly lower responses in cells clamped at -90 mV. At the same time, tetracaine inhibited voltage induced calcium release. Voltage and tetracaine modulation over the action of caffeine (500 microM) was also observed. Pretreatment of cells with 10 microM nifedipine abolished the caffeine induced fluorescence response in non-clamped cells. These findings suggest that, in cultured muscle cells, calcium release through the caffeine and tetracaine sensitive pathways is controlled by both membrane potential and the dihydropyridine receptor.

Evaluation of the incremental diagnostic value and impact on patient treatment of thallium scintigraphy.

The incremental diagnostic yield of exercise 201Tl scintigraphy with visual and quantitative analysis was determined in 191 patients with known or suspected coronary artery disease (CAD). The coronary arteriogram was used as the gold standard. After pre-test clinical and exercise electrocardiographic data were taken into consideration, scintigraphy was found to have additional diagnostic value both in the diagnosis of CAD and of multivessel disease, with quantitative analysis being superior to visual analysis. The impact of 201Tl scintigraphy on the patient's treatment--conservative treatment versus revascularization--was also evaluated. The impact was relatively low, as the decision for revascularization was based primarily on the angiographic result and the severity of the anginal pain. This result reflects only the decision making process used in our clinic and permits no conclusion to be made concerning the possible value of 201Tl scintigraphy in this type of medical decision making process.

Different efficacy of specific agonists at 5-HT3 receptor splice variants: the role of the extra six amino acid segment.

1. Whole cell voltage clamp electrophysiology and radioligand binding were used to examine the agonist characteristics of the two splice variants of the 5-HT3 receptor which have been cloned from neuronal cell lines. Homo-oligomeric 5-HT3 receptors were examined in HEK 293 cells stably transfected with either long (5-HT3-L) or short (5-HT3-S) receptor subunit DNAs. 2. Functional homo-oligomeric receptors were formed from both subunits, and responses to 5-HT3 receptor agonists (5-hydroxytryptamine (5-HT), 2-methyl 5-HT and m-chlorophenylbiguanide) were qualitatively similar. 3. Maximum currents (Rmax) elicited by the 5-HT3 receptor agonists m-chlorophenylbiguanide (mCPBG) and 2-methyl-5-HT (2-Me-5-HT), as compared to 5-HT, differed in the two splice variants: Rmax mCPBG/Rmax 5-HT values were 0.68+/-0.04 and 0.91+/-0.01 in 5-HT3-L and 5-HT3-S receptors, respectively. Comparable values for 2-Me-5-HT were 0.30+/-0.02 and 0.23+/-0.02. 4. Radioligand binding data showed no difference in affinity of agonist or antagonist binding sites; thus the six amino acid deletion appears to cause differences in agonist efficacy. 5. The role of the 6 amino acid insertion was further investigated by use of site-directed mutagenesis to create two mutant receptors, one where serine 286 was replaced with alanine, and the second where all 6 amino acids were replaced with alanines. 6. Examination of the mutant receptors when stably expressed in HEK 293 cells revealed agonist properties resembling long and not short 5-HT3 receptors. Thus specific amino acids in this region are not responsible for the observed differences. 7. The data show intracellular structure can have significant effects on ligand-gated ion channel function, and suggest that minor changes in structure may be responsible for differences in function observed when ligand-gated ion channel proteins are modulated intracellularly.

A randomized, placebo-controlled study of loop diuretics in patients with essential hypertension: the bumetanide and furosemide on lipid profile (BUFUL) clinical study report.

This study was conducted to determine whether loop diuretics are more effective than placebo in reducing blood pressure without raising serum lipid levels, and whether bumetanide is more effective than furosemide in this respect. In a double-blind, 24-week placebo-controlled crossover study, 27 patients with essential hypertension were treated in four periods of 6 weeks each, including placebo twice, furosemide 40 mg daily, and bumetanide 1 mg daily. Several metabolic parameters, including serum lipid levels, and blood pressure were assessed. Overall levels of total cholesterol, triglycerides, and low-density lipoprotein (LDL) cholesterol were 5%, 12.4%, and 4.8% higher, respectively, during loop diuretic therapy than during placebo treatment. Overall systolic and diastolic blood pressure measurements were 12 mmHg and 4 mmHg lower, respectively, during loop diuretic therapy than during placebo treatment. Any added effect of bumetanide on serum lipid levels and blood pressure compared with furosemide, however, could not be confirmed. Our results indicate that the loop diuretics bumetanide and furosemide are effective in reducing blood pressure, and influence serum lipid levels markedly less than do thiazide diuretics or chlorthalidone. In addition, these results indicate that differences in blood pressure reduction and serum lipid levels between the two compounds were small and nonsignificant.

Trisomy of chromosome 22 in acute myelomonocytic leukemia.

A patient with acute myelomonocytic leukemia type M4, with a trisomy 22 as the only chromosomal abnormality is reported. All six previously published cases with this anomaly had acute myeloid leukemia. The subtype was AMMoL in five patients, and the subtype of the sixth one was not indicated.

The role of the agonist binding site in Ca(2+) inhibition of the recombinant 5-HT(3A) receptor.

The mechanism and site of action of Ca(2+) at the recombinant murine 5-hydroxytryptamine (5-HT)(3A) receptor were investigated using whole-cell voltage clamp, radioligand binding and single-cell Ca(2+) imaging. Inhibition of the 5-HT (3 microM)-induced response by 10 mM Ca(2+) reached a plateau at 68.5% inhibition, with half-maximal effect at 2.6 mM. This was due to an increase in EC(50) from 2.35 to 3.87 microM and a 30% reduction in I(max). Ca(2+) also resulted in the inhibition of binding of both 5-HT(3) receptor agonist [3H]m-chlorophenylbiguanide and antagonist [3H]granisetron due to an increase in K(d), with no change in B(max). An increase in EC(50) from 2.6 (1 mM Ca(2+)) to 4.7 microM (10 mM Ca(2+)), with no change in maximal [Ca(2+)](i), was observed from Ca(2+) imaging studies. Largely similar effects were observed with Mg(2+). The combined data suggest that Ca(2+) acting at a site that directly or indirectly influences the agonist binding site plays a significant role in its inhibitory effect at the 5-HT(3) receptor.

Head-to-head comparison between technetium-99m-sestamibi and thallium-201 tomographic imaging for the detection of coronary artery disease using combined dipyridamole-exercise stress.

AIM: The purpose of this study was a head-to-head comparison of tomographic imaging (SPECT) with technetium-99m (Tc-99m)-sestamibi and thallium-201 (Tl-201) using dipyridamole-low-level bicycle exercise stress for the assessment of coronary artery disease. METHODS: We studied 38 consecutive patients referred for the evaluation of chest pain who had undergone coronary angiography. The patients were randomly allocated to Tc-99m-sestamibi SPECT followed by Tl-201 SPECT or vice versa. The accuracy of both tracers in detecting significant coronary artery disease (> 50% luminal stenosis) was 87% (95% confidence interval 72-96%). Only two patients were classified differently by the two methods. RESULTS: On a segmental basis, good agreement was found between Tc-99m-sestamibi and Tl-201 for both the localization and the nature of perfusion defects (reversible or persistent) identified (Cohen's kappa = 0.67). CONCLUSION: No clinically relevant differences in diagnostic accuracy were demonstrated between Tc-99m-sestamibi and Tl-201 SPECT using combined dipyridamole-exercise stress for the evaluation of coronary artery disease.