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Copyright of Der Nervenarzt is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Deep brain stimulation (DBS) represents an established treatment option in a growing number of movement disorders. Recent case reports suggest beneficial effect of globus pallidus internus (GPi)-DBS in selected patients suffering from Huntington's disease with marked disabling chorea. We present a 41-year-old man with genetically confirmed HD following quadruple GPi- and subthalamic nucleus (STN)-DBS. Motor function was assessed by Abnormal Involuntary Movement Scale (AIMS) and by Unified Huntington Disease Rating Scale (UHDRS) presurgery and postsurgery for up to 4 years. Furthermore, cognitive, neuropsychiatric state and quality of life (QoL) including life satisfaction (QLS) were annually evaluated. Chorea assessed by AIMS and UHDRS subscores improved by 52 and 55 %, 45 and 60 %, 35 and 45 % and 55-66 % at 1-4 years, respectively, compared to presurgical state following GPi-STN-DBS. During these time periods bradykinesia did not increase following separate STN- and combined GPi-STN-DBS compared to presurgical state. Mood, QoL and QLS were ameliorated. However, dysexecutive symptoms increased at 4 years postsurgery. The present case report suggests that bilateral GPi- and STN-DBS may represent a new treatment avenue in selected HD patients. Clinically, GPi-DBS attenuated chorea and was associated with a larger effect-adverse effect window compared to STN-DBS. However, GPi-DBS-induced bradykinesia may emerge as one main limitation of GPi-DBS in HD. Thus, quadruple GPi-STN-DBS may be indicated, if separate GPi-DBS does not result in sufficient control of motor symptoms. Future controlled studies need to confirm if the present anecdotal observation of additive beneficial effects of GPi- and STN-DBS in a HD patient with severe generalized chorea and relatively intact cognitive and affective functions indeed represents a new therapeutic option. [ABSTRACT FROM AUTHOR]

Aims/hypothesis: Inspired by recent speculation about the potential utility of α-antagonism in the treatment of type 2 diabetes, the study examined the contribution of α-antagonism vs other mechanisms to the antihyperglycaemic activity of the imidazoline (±)-efaroxan. Methods: Effects of the racemate and its pure enantiomers on isolated pancreatic islets and beta cells in vitro, as well as on hyperglycaemia in vivo, were investigated in a comparative manner in mice. Results: In isolated perifused islets, the two enantiomers of efaroxan were equally potent in counteracting inhibition of insulin release by the ATP-dependent K (K) channel-opener diazoxide but (+)-efaroxan, the presumptive carrier of α-antagonistic activity, was by far superior in counteracting inhibition of insulin release by the α-agonist UK14,304. In vivo, (+)-efaroxan improved oral glucose tolerance at 100-fold lower doses than (−)-efaroxan and, in parallel with observations made in vitro, was more effective in counteracting UK14,304-induced than diazoxide-induced hyperglycaemia. The antihyperglycaemic activity of much higher doses of (−)-efaroxan was associated with an opposing pattern (i.e. with stronger counteraction of diazoxide-induced than UK14,304-induced hyperglycaemia), which implicates a different mechanism of action. Conclusions/interpretation: The antihyperglycaemic potency of (±)-efaroxan in mice is almost entirely due to α-antagonism, but high doses can also lower blood glucose via another mechanism. Our findings call for reappraisal of the possible clinical utility of α-antagonistic compounds in recently identified subpopulations of patients in which a congenitally higher level of α-adrenergic activation contributes to the development and pathophysiology of type 2 diabetes. [ABSTRACT FROM AUTHOR]

The algae living endosymbiotically within coral are thought to increase algal pigmentation with increasing depth to capture the diminishing light. Here, we follow distribution of the hermatypic coral Seriatopora hystrix along a 60-m bathymetric gradient in the Gulf of Eilat, Red Sea, to study coral ecophysiology and response to light regimes. Combining work on coral morphology, pigment content and genotyping of the photosymbiont, we found that total chlorophyll concentration per zooxanthellae cell and the dark- and light-acclimated quantum yield of photosystem II did not vary significantly along the 60-m gradient. However, the chlorophyll a/c ratio increased with depth. This suggests that the symbiotic algae in S. hystrix possess a mechanism for acclimatization or adaptation that differs from previously described pathways. The accepted photoacclimatory process involves an increase in chlorophyll content per alga as light intensity decreases. Based on corallite and branch morphology, this research suggests that S. hystrix has two depth-dependent ecophenotypes. Above 10 m depth, S. hystrix exhibits sturdier colony configurations with thick branches, while below 30 m depth, colonies are characterized by thin branches and the presence of a larger polyp area. Between 10 and 30 m depth, both ecophenotypes are present, suggesting that corallite morphology may act as another axis of photoacclimation with depth. [ABSTRACT FROM AUTHOR]

Copyright of Manuelle Medizin is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of BHM Berg- und Hüttenmännische Monatshefte is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of BHM Berg- und Hüttenmännische Monatshefte is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Rationale: Daytime fatigue, which at the neuro-physiological level is due to vigilance decrements, is a frequent complaint in postmenopausal women. Objectives: In a three-arm, 2-month, parallel group-design study, vigilance-promoting effects of a novel continuous combination (=Climodien 2/3) of estradiol valerate (EV; 2 mg) and dienogest (DNG; 3 mg) were compared with the effects of both EV alone and placebo in 55 insomniac, postmenopausal syndrome patients. Methods: Low-resolution brain electromagnetic tomography (LORETA) was undertaken to identify the cerebral target regions of hormone replacement therapy. Results: An omnibus significance test revealed Climodien to increase activity in 882 of 2,394 voxels in the alpha-2 band, followed by 733, 706, and 664 voxels in the beta-2, beta-1, and beta-3 bands, and 509 voxels in the delta band, whereas 2 mg EV alone did not produce a significant suprathreshold activity. Current density increased predominantly in the right hemisphere, which had already been described in the literature as the center of the vigilance system. In the fast alpha range, which plays a major role in the context of vigilance, increased activity was found in the right prefrontal, temporal, and superior parietal cortices, i.e., those brain areas of the right-sided fronto-parietal neuronal network that are responsible for sustained attention. A further activity increase was seen in the anterior cingulate gyrus associated with attentional control and conflict monitoring. The right temporal lobe showed increased current density in all frequency bands. Conclusions: Electroencephalographic tomography (LORETA) identified the right-hemispheric vigilance system as the target region of Climodien. [ABSTRACT FROM AUTHOR]

Parametric four-wave mixing, stimulated electronic Raman scattering and amplified spontaneous emission cascades have been studied experimentally by single-photon resonant and near-resonant excitation of the 4 P levels of dense sodium vapour. The dependence of emission intensities on laser detuning and exciting laser power is discussed. [ABSTRACT FROM AUTHOR]

The locomotor response of juvenile Ginglymostoma cirratum, the nurse shark, to six covert, discrete sources of an attractant chemical stimulus (fresh shrimp extract) was monitored in a tank (5×5×0.5 m) by means of a square matrix of 1936 photocells embedded in the floor and an on line computer. The experiments were done in flowing (1.17 cm/s) and stagnant water in order to determine the effects of flow on the accuracy of localization and to clarify some of the locomotor mechanisms involved. The response was quantified by a temporal and spatial analysis of activity, distance travelled, mean velocity, mean turn size, step length between turns and its direction vector, frequency of turning, the time spent by the animal in the quadrants of the tank, the mean direction vector of the steps and computer plots of locomotor pathways. For controls, the locomotion was monitored in the absence of chemical stimulation and with a placebo (seawater) replacing the shrimp extract. Five animals were used in 22 experiments in flowing, 20 in stagnant water. The relationship between each of the above-mentioned locomotor variables and the position of the discrete source of stimulation was examined by regression analyses and compared quantitatively between flowing and stagnant water. Localization is very precise in flowing water and is dependent on the gradient of the stimulus in the medium. Downstream sites of stimulation are better localized than upstream ones. In stagnant water only generalized localization occurs. The flowing water provides the direction vector for precise localization. [ABSTRACT FROM AUTHOR]

Abstract. The dependence of the yellow conical emission angle on pump laser intensity is studied experimentally in dense Na vapor under near-resonant one-photon excitation of the sodium 4[sup 2]P levels. A numerical model developed to describe mechanisms involved in the conical emission generation processes indicates that the saturation observed is due to the opposite angular tuning of the near-infrared and yellow conical emission generated in the same process. The mechanisms responsible are assigned to (self)induced phase modulation processes of the waves involved. [ABSTRACT FROM AUTHOR]

The canine has become an accepted research model for the examination of a number of human clinical conditions. Despite it's status as a research model, little is known regarding the peripheral effects of inflammatory mediator substances. Products of arachidonic acid metabolism (leukotrienes) are reported capable of altering leukocyte functions. Because of the emerging importance of the canine research model and leukotrienes we examined the effects of leukotriene B (LTB) on several in vitro functions of isolated canine peripheral polymorphonuclear leukocytes (PMN). Changes in forward angle light scatter properties of the cells were used as one measure of PMN activation. Other functional changes examined following LTB pretreatment included chemotactic capability, the electrophysiological state of the cell plasma membrane, and the metabolic oxidative response (i. e. HO production). Random cellular movement of PMNs increased by 120% and 72% following preincubation with 10 and 10 M LTB, respectively. LTB between 10 and 10 M did not significantly alter cellular resting membrane potential. Between 10 and 10 M LTB elicited significant levels of cellular HO production. Although significant, HO production was <40% that induced by phorbol myristate acetate (PMA). In numerous respects, canine in vitro PMN responses parallel previous reports of human cell function(s) in the presence of inflammatory mediators and may represent an attractive alternative for investigation of PMN dysfunctions. [ABSTRACT FROM AUTHOR]

There is little information about the interaction between melatonin, sexual steroids and neuroendocrine system in postmenopausal females, even if former research showed that melatonin is clearly involved in human physiology and pathophysiology. We evaluated the overnight urinary excretion of 6-sulfatoxymelatonin (6-SMT) using a radioimmunoassay in 60 postmenopausal women. The group has been divided into patients with insomnia (10), hyperprolactinemia (7), depression (9), obesity (7) and controls (27). Compared to controls 6-SMT values were significantly higher in depressive females. Patients with hyperprolactinemia showed a trend toward a significantly elevated average nocturnal melatonin concentration. Melatonin levels were significantly lower in patients with insomnia and obese postmenopausal females than in controls. Since previous studies described lower melatonin levels in postmenopausal than in premenopausal women, the indication of melatonin therapy, especially for sleep disorders in this collective, can be handled more generously. Melatonin should be prescribed restrictively in patients with depression and in those with hyperprolactinemia. The role of melatonin in obese females remains unclear. [ABSTRACT FROM AUTHOR]

Soft-agar clonogenic assay techniques were used to examine 2 sources of colony-stimulating activity (CSA), submandibular gland-conditioned medium (SMG-CM) and pregnant mouse uterine extract (PMUE), for potentiation of granulocyte-macrophage (GM-CFUc) or monocyte-macrophage (M-CFUc) progenitor cell populations. The femoral populations being examined were aspirated from normal mice and from those bearing 1 of 2 types of tumor: Lewis lung carcinoma (3LL) or thymic lymphoma ascites tumor (EL-4). When PMUE was used as a CSA source, normal animals showed a greater clonogenic response per population than either of the tumor-bearing groups. When SMG-CM was used as a CSA source, the pattern of GM-CFUc response was much different: GM-CFUc magnitudes increased by fourfold to sixfold over normal levels in tumor-bearing animals. M-CFUc response patterns were also significant, being similar in response but smaller. [ABSTRACT FROM AUTHOR]