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In both diurnal and nocturnal mammals, the timing of activity is regulated by the central circadian clock of the suprachiasmatic nucleus (SCN). The SCN is synchronized to the external light cycle via the retinohypothalamic tract (RHT). To investigate potential differences in light processing between nocturnal mice and the diurnal rodent Rhabdomys pumilio, we mimicked retinal input by stimulation of the RHT ex vivo. Using Ca2+ imaging, we observed excitations as well as inhibitions of SCN neurons in response to electrical RHT stimulation. In mice, the vast majority of responses were excitatory (85%), whereas in Rhabdomys, the proportion of excitatory and inhibitory responses was similar (51% excitatory, 49% inhibitory). Glutamate blockers AP5 and CNQX blocked the excitatory responses to RHT stimulation but did not abolish the inhibitory responses in mice or Rhabdomys, indicating that the inhibitions were monosynaptically transmitted via the RHT. Simultaneous application of glutamate blockers with the GABA(A) antagonist gabazine blocked all inhibitory responses in mice, but not in Rhabdomys. Collectively, our results indicate that in Rhabdomys, considerably more inhibitory responses to light are present and that these responses are driven directly by the RHT. We propose that this increased proportion of inhibitory input could reflect a difference in the entrainment mechanism employed by diurnal rodents.

Cl−-sensitive with-no-lysine kinase (WNK) plays a key role in regulating the thiazide-sensitive Na+-Cl−cotransporter (NCC) in the distal convoluted tubule (DCT). Cl−enters DCT cells through NCC and leaves the cell across the basolateral membrane via the Cl−channel ClC-K2 or K+-Cl−cotransporter (KCC). While KCC is electroneutral, Cl−exit via ClC-K2 is electrogenic. Therefore, an alteration in DCT basolateral K+channel activity is expected to influence Cl−movement across the basolateral membrane. Although a role for intracellular Cl−in the regulation of WNK and NCC has been established, intracellular Cl−concentrations ([Cl−]i) have not been directly measured in the mammalian DCT. Therefore, to measure [Cl−]iin DCT cells, we generated a transgenic mouse model expressing an optogenetic kidney-specific Cl-Sensor and measured Cl−fluorescent imaging in the isolated DCT. Basal measurements indicated that the mean [Cl−]iwas ~7 mM. Stimulation of Cl−exit with low-Cl−hypotonic solutions decreased [Cl−]i, whereas inhibition of KCC by DIOA or inhibition of ClC-K2 by NPPB increased [Cl−]i, suggesting roles for both KCC and ClC-K2 in the modulation of [Cl−]i. Blockade of basolateral K+channels (Kir4.1/5.1) with barium significantly increased [Cl−]i. Finally, a decrease in extracellular K+concentration transiently decreased [Cl−]i, whereas raising extracellular K+transiently increased [Cl−]i, further suggesting a role for Kir4.1/5.1 in the regulation of [Cl−]i. We conclude that the alteration in ClC-K2, KCC, and Kir4.1/5.1 activity influences [Cl−]iin the DCT.

Selective laser sintering (SLS) of thermoplastic powders allows for the creation of parts with complex geometries and functionally robust designs. Based on the principle of selectively fusing regions in a layer-by-layer process, SLS has gained increasing interest as an economical way to supplement small batch production for traditional manufacturing techniques. To introduce SLS parts into functionally demanding applications, it is imperative that they exhibit good surface quality to prevent wear caused by surface friction. Parts produced with SLS, however, typically have a higher surface roughness than those produced through traditional manufacturing techniques. Understanding the relationship between processing parameters and surface quality will allow one to better predict and control surfaces for end-use parts. A design of experiments was formulated to investigate the effects of four process parameters on parts produced across the powder bed: powder type, roller speed, laser power, and scan spacing. To analyze the surface roughness and area ratio of the parts, Focus Variation (FV) technology was implemented. Statistical models were developed to estimate the surface roughness and area ratio of manufactured specimens.

Both inhibitory and excitatory GABA transmission exist in the mature suprachiasmatic nucleus (SCN), the master pacemaker of circadian physiology. Whether GABA is inhibitory or excitatory depends on the intracellular chloride concentration ([Cl−]i). Here, using the genetically encoded ratiometric probe Cl-Sensor, we investigated [Cl−]i in AVP and VIP-expressing SCN neurons for several days in culture. The chloride ratio (RCl) demonstrated circadian rhythmicity in AVP + neurons and VIP + neurons, but was not detected in GFAP + astrocytes. RCl peaked between ZT 7 and ZT 8 in both AVP + and VIP + neurons. RCl rhythmicity was not dependent on the activity of several transmembrane chloride carriers, action potential generation, or the L-type voltage-gated calcium channels, but was sensitive to GABA antagonists. We conclude that [Cl−]i is under circadian regulation in both AVP + and VIP + neurons.

The passive surveillance system is an important tool in pharmacovigilance of vaccines. However, reporting of adverse events following immunization (AEFI) post-marketing has limitations regarding under-reporting, biased reports and lack of exposure data resulting in imprecise estimates. New mobile application technology may provide an opportunity for an enhanced surveillance. A pre-requisite for the use of new app-based technology is to identify practical challenges and end users' preferences for design of app-features. The objectives were (i) to investigate the recruitment and feasibility of an app-based study in Germany, (ii) to assess individuals' motivation to participate in such a study and (iii) to identify app-features for reporting AEFI. We conducted a cross-sectional study among employees of a financial institution who attended the occupational health office during the seasonal influenza vaccination in November 2017. Participants tested feasibility and assessed an app prototype for AEFI reporting by using a case vignette and a questionnaire. Of the 153 attending employees, 65 (42%) agreed to participate and returned the questionnaire. Twenty-three (63%) rated the experience of reporting AEFI with the app prototype to be positive. Among three features offered for gamification, collecting points was most frequently chosen (n=22, 34%). The main reason for declining participation was the apprehension about data protection (n=28, 43%). Results suggest that the app-based technology was well accepted and is a suitable supplement for AEFI reporting and in our study. A convincing data protection concept is likely to enhance acceptability of such a system.

Background The kidney plays a key role in the regulation of K+ excretion and K+ homeostasis. Previous studies have demonstrated that the thiazide-sensitive Na-Cl cotransporter (NCC) in the distal convoluted tubule (DCT) plays an important role in the regulation of renal K+ excretion by controlling sodium and volume delivery to the distal nephron. It has been shown that NCC is inhibited when K+ intake is high and activated when dietary K+ intake is low. It is now generally accepted that WNKs (with-no-lysine kinases) plays a major role in NCC phosphorylation and activation. A large body of evidence has demonstrated that WNK1 and WNK4 are chloride-sensitive kinases, which are inhibited by high intracellular chloride concentration ([Cl-]i) and activated by low [Cl-]i. It has also been suggested that membrane voltage changes by extracellular K+ concentrations are responsible for altering the [Cl-]i thereby affecting WNK activity. The aim of our study is to test the hypothesis that changes in the basolateral cell voltage alter the [Cl-]i in the DCT. Methods To determine the [Cl-]i in the DCT, we have used isolated single DCT tubule of transgenic mice expressing Cl-sensor, a chloride-sensitive fluorescent protein modified from Chlomeleon. The Cl-sensor includes both yellow and cyan fluorescent moieties, allowing ratiometric estimation of [Cl-]i. Results We first measured the [Cl-]i in the isolated DCT by establishing the calibration curve. Using this calibration curve, we estimated that basal DCT [Cl-]i is 7± 2.3mM (n=18) . Changing the extracellular potassium concentration from 10 mM to 2 mM decreases the [Cl-]i. To test the role of the basolateral Kir4.1/Kir5.1 of the DCT in altering [Cl-]i, we examined whether inhibition of the basolateral K+ channels with Ba2+ would increase the [Cl-]i since Ba2+ has been shown to depolarize DCT membrane. Indeed, Inhibition of Kir4.1/Kir5.1 significantly increased the [Cl-]i in the DCT bathed in a solution containing 2 mM K+. Conclusion Our results indicate that the intracellular Cl- concentrations of DCT cells are low at baseline and that the depolarization increases whereas hyperpolarization decreases the intracellular Cl- concentrations. Thus, changes in DCT voltage are associated with alteration of intracellular Cl- concentrations. &nbsp

Objectives: There are no data available on the quality of care after discharge from hospital and only limited data are available on the psychosocial effects of being an MRSA carrier within the German health system. Methods: Patients who tested positive for MRSA in the previous year were invited to take part in focus groups. Results: 2 focus groups with a total of 9 MRSA-carriers were conducted. The level of knowledge about MRSA differed between participants. In some cases, lack of information led to uncertainty and inappropriate measures to counteract MRSA. Some participants restricted their social contacts, especially to children, in order to prevent transmission. Patients experienced stigmatization in the health care system more often in inpatient care than in the outpatient sector. Only in a few cases both eradication therapy and swabs for control purposes were carried out. Conclusions: Information about the appropriate treatment and management of MRSA should be made available to patients more easily; in particular, patients need to be informed that MRSA is no threat to healthy individuals. Despite the desire of MRSA-carriers to become MRSA negative, treatment and control of MRSA seem to have low priority in the ambulant health care sector in Germany.

Several reports have described excitatory GABA transmission in the suprachiasmatic nucleus (SCN), the master pacemaker of circadian physiology. However, there is disagreement regarding the prevalence, timing, and neuronal location of excitatory GABA transmission in the SCN. Whether GABA is inhibitory or excitatory depends, in part, on the intracellular concentration of chloride ([Cl−]i). Here, using ratiometric Cl− imaging, we have investigated intracellular chloride regulation in AVP and VIP-expressing SCN neurons and found evidence suggesting that [Cl−]i is higher during the day than during the night in both AVP+ and VIP+ neurons. We then investigated the contribution of the cation chloride cotransporters to setting [Cl−]i in these SCN neurons and found that the chloride uptake transporter NKCC1 contributes to [Cl−]i regulation in SCN neurons, but that the KCCs are the primary regulators of [Cl−]i in SCN neurons. Interestingly, we observed that [Cl−]i is differentially regulated between AVP+ and VIP+ neurons-a low concentration of the loop diuretic bumetanide had differential effects on AVP+ and VIP+ neurons, while blocking the KCCs with VU0240551 had a larger effect on VIP+ neurons compared to AVP+ neurons.

SK2-containing channels are expressed in the postsynaptic density (PSD) of dendritic spines on mouse hippocampal area CA1 pyramidal neurons and influence synaptic responses, plasticity and learning. The Sk2 gene (also known as Kcnn2) encodes two isoforms that differ only in the length of their N-terminal domains. SK2-long (SK2-L) and SK2-short (SK2-S) are coexpressed in CA1 pyramidal neurons and likely form heteromeric channels. In mice lacking SK2-L (SK2-S only mice), SK2-S-containing channels were expressed in the extrasynaptic membrane, but were excluded from the PSD. The SK channel contribution to excitatory postsynaptic potentials was absent in SK2-S only mice and was restored by SK2-L re-expression. Blocking SK channels increased the amount of long-term potentiation induced in area CA1 in slices from wild-type mice but had no effect in slices from SK2-S only mice. Furthermore, SK2-S only mice outperformed wild-type mice in the novel object recognition task. These results indicate that SK2-L directs synaptic SK2-containing channel expression and is important for normal synaptic signaling, plasticity and learning.

Zusammenfassung »Starke« Familien, so das Ergebnis vieler Untersuchungen, machen Kontinuitat und Erfolg eines Familienunternehmens wahrscheinlicher. Doch auch das geteilte Eigentum an einem Unternehmen kann das Entstehen gesunder Grosfamilien begunstigen, wie man sie in westlichen Breiten sonst selten findet. Mit einem Betrieb, so wird im vorliegenden Text argumentiert, kauft sich die Unternehmensfamilie bestimmte Zumutungen ein, an deren Bewaltigung sie sich aufrichten kann. Das gelingt allerdings nur in seltenen Fallen. Doch ausgerechnet in denen sind oft eigenartige Routinen und Instrumente im Spiel, die man jenseits von Familienunternehmen und ihren Familie kaum zu sehen bekommt. Der Text geht der Frage nach, wie sich solche Hilfsmittel mit der Langlebigkeit und Stabilitat groser Unternehmensfamilien in Verbindung bringen lassen. Fur mit dem Gegenstand weniger vertraute Leser wird die Thematik einfuhrend in den Kontext der Familienunternehmensforschung und Ratgeberliteratur gestellt.

Background: Short-acting anesthetic agents are suitable and commonly used in ocular surgery. Propofol and remifentanil are known to reduce intraocular pressure (IOP), but no information is available regarding the effects of sevoflurane combined with remifentanil on IOP. Methods: Therefore, a prospective, randomized study was conducted to compare the effects on IOP of two different anesthetic techniques: one based on a total intravenous anesthesia with propofol (Group P, bolus 1.5–2.0 mg/kg, maintenance 3.0–7.0 mg/kg/h); and the other based on sevoflurane (Group S, inhalational induction, end-tidal concentration 0.7–1.2 vol.%). An infusion of remifentanil (10 µg/kg/h) was used with both techniques. In ASA I–III patients with normal IOP undergoing elective cataract surgery, using an applanation tonometer, IOP was measured contralateral to the operated eye at nine predefined time points before, during and after anesthesia. Results: The two groups (n=20 each) were comparable with regard to demographic data and hemodynamic variables. Baseline IOP was 14.2±2.8 mmHg (Group P) and 14.1±2.4 mmHg (Group S; NS). During and following the induction of anesthesia, IOP was reduced in both groups. Intraocular pressure was significantly lower in Group P (6.0±3.2 mmHg) than in Group S (8.9±3.4 mmHg) during the induction of anesthesia. Conclusion: In patients undergoing cataract surgery under general anesthesia with tracheal intubation, anesthetic regimens with propofol as well as with sevoflurane, both combined with remifentanil, decrease IOP significantly. The decrease in IOP was significantly more pronounced in the propofol group than in the sevoflurane group.

GABAergic neurotransmission is a fundamental component of the suprachiasmatic nucleus (SCN) neural network, and virtually all SCN neurons communicate using GABA as a neurotransmitter. GABAergic neurotransmission plays a critical role in light-induced phase shifts, synchronization of the dorsal and ventral SCN, and, although controversial, synchronization of the circadian phase of individual SCN neurons. The circadian clock regulates the strength of GABAA receptor-mediated neurotransmission although the signaling mechanisms mediating this regulation are not known. GABA released from axon terminals acts on synaptic GABAA receptors producing postsynaptic currents that have a rapid onset and offset and desensitize in the continued presence of GABA. In the SCN, the postsynaptic GABAA receptor-mediated currents may be excitatory or inhibitory depending on the time of day. Once released GABA is removed from the synaptic cleft by specific sodium–chloride-dependent transporters (GAT). Some GABA can diffuse out of the synaptic cleft and act on extrasynaptic GABAA receptors. These extrasynaptic GABAA receptors have high affinity for GABA and show little or no desensitization. They mediate a “tonic” GABAA current that could modulate the input–output characteristics of individual SCN neurons. While significant scientific questions remain about the roles of GABAergic neurotransmission in the circadian timing signals, recent findings have yielded important advances in our understanding of GABAergic neurotransmission in the SCN.

Aim: The long-acting insulin analogue detemir (Levemir®) has structural and physicochemical properties which differ from human insulin. The aim of the present study was to test whether this leads to altered hormone and symptom response during hypoglycaemia. Methods: 12 healthy subjects [6f/6m, age 32 ± 6 years (mean ± s.d.), body mass index (BMI) 24.2 ± 2.5 kg/m2] underwent a 200-min stepwise hypoglycaemic clamp (45 min steps of 4.4, 3.7, 3.0 and 2.3 mmol/l) with either detemir or human insulin in random order. A bolus of detemir (660 mU/kg) or human insulin (60 mU/kg) was given before insulin was infused at a rate of 5 (detemir) or 2 (human insulin) mU/kg/min. Blood was drawn and a semi-quantitative symptom questionnaire was administered before and after each plateau of the hypoglycaemic clamp. Cognitive function was assessed during each step. Results: Blood glucose levels and glucose infusion rates were comparable with detemir and human insulin. The total symptom score was higher with detemir during the 3 and 2.3 mmol glucose step compared to human insulin (p = 0.048). Especially sweating was increased with detemir (p = 0.02) with an earlier and faster increase during the clamp (interaction insulin × time: p = 0.04). No significant differences between detemir and human insulin in cortisol, norepinephrine, epinephrine, glucagon, growth hormone, lactate or free fatty acid (FFA) levels during hypoglycaemia were observed, and there were no significant differences in cognitive function tests. Conclusions: Insulin detemir increased symptom awareness during hypoglycaemia compared to human insulin in healthy individuals, whereas counter-regulatory hormone response and cognitive function were unaltered.

Short-acting anesthetic agents are suitable and commonly used in ocular surgery. Propofol and remifentanil are known to reduce intraocular pressure (IOP), but no information is available regarding the effects of sevoflurane combined with remifentanil on IOP.Therefore, a prospective, randomized study was conducted to compare the effects on IOP of two different anesthetic techniques: one based on a total intravenous anesthesia with propofol (Group P, bolus 1.5-2.0 mg/kg, maintenance 3.0-7.0 mg/kg/h); and the other based on sevoflurane (Group S, inhalational induction, end-tidal concentration 0.7-1.2 vol.%). An infusion of remifentanil (10 microg/kg/h) was used with both techniques. In ASA I-III patients with normal IOP undergoing elective cataract surgery, using an applanation tonometer, IOP was measured contralateral to the operated eye at nine predefined time points before, during and after anesthesia.The two groups (n=20 each) were comparable with regard to demographic data and hemodynamic variables. Baseline IOP was 14.2+/-2.8 mmHg (Group P) and 14.1+/-2.4 mmHg (Group S; NS). During and following the induction of anesthesia, IOP was reduced in both groups. Intraocular pressure was significantly lower in Group P (6.0+/-3.2 mmHg) than in Group S (8.9+/-3.4 mmHg) during the induction of anesthesia.In patients undergoing cataract surgery under general anesthesia with tracheal intubation, anesthetic regimens with propofol as well as with sevoflurane, both combined with remifentanil, decrease IOP significantly. The decrease in IOP was significantly more pronounced in the propofol group than in the sevoflurane group.

Six hundred forty newly-admitted schizophrenic men in 35 VA hospitals were randomly assigned to chlorpromazine, triflupromazine, mepazine, prochlorperazine, perphenazine and phenobarbital groups. Treatment followed a double blind procedure for 12 weeks. Patients were started on low "equivalent" doses of each drug which were gradually increased in a predetermined manner during the first 4 weeks. During the final 8 weeks, each prescribing physician adjusted the dose for each of his patients in order to evoke an optimal therapeutic response. Average daily doses during the flexible period were: chlorpromazine, 635 mg.; triflupromazine, 175 mg.; mepazine, 190 mg. ; prochlorperazine, 90 mg. ; and perphenazine, 50 mg. Clinical evaluations using two rating scales provided 24 criteria of change. For each criterion, the mean of each of the 6 treatment groups adjusted for the net effect of 12 control variables was compared by analysis of multiple covariance with the mean of every other treatment group at each of thr...

Chlordiazepoxide, paraldehyde, perphenazine and sodium pentobarbital all produced similarly favorable results in the treatment of uncomplicated delirium tremens. Drugs that are cross-dependent with...

Polypharmacy with psychoactive drugs was surveyed in 1276 elderly psychiatric patients from 12 Veterans Administration hospitals. One out of every six patients received two or more psychoactive agents. No specific combination of drugs was overly popular. The most frequently administered combinations, thioridazine plus phenobarbital and chlorpromazine plus phenobarbital, were administered to only 13 patients each (1% of the sample). The large majority of the combinations involved antipsychotic agents. One antipsychotic drug, thioridazine, was a component of nearly one-third of the combinations. The most frequent pairings were an antipsychotic drug plus and antidepressant, two antipsychotic drugs, and an antipsychotic drug plus an antianxiety agent or sedative-hypnotic. The use of polypharmacy was significantly related to patient age. One out of every four patients 60 to 65 years of age received two or more psychoactive drugs compared to only one out of eight over 75 years of age. The implications of these findings for treatment and research are discussed.

A double-blind study of 537 patients evaluated the relative efficacy of four drugs—chlordiazepoxide, chlorpromazine, hydroxyzine, and thiamine—commonly used in treating alcohol withdrawal symptoms, specifically to prevent delirium tremens and convulsions. Of the 55 patients who developed these symptoms, two percent were in the chlordiazepoxide group; the incidence ranged from ten to 16 percent in the other treatment groups. The authors conclude that chlordiazepoxide appears to be the drug of choice among those tested.