Optimized genetic code expansion technology for time-dependent induction of adhesion GPCR-ligand engagement

The introduction of an engineered aminoacyl-tRNA synthetase/tRNA pair enables site-specific incorporation of unnatural amino acids (uAAs) with functionalized side chains into proteins of interest. Genetic Code Expansion (GCE) via amber codon suppression confers functionalities to proteins but can also be used to temporally control the incorporation of genetically encoded elements into proteins. Here, we report an optimized GCE system (GCEXpress) for efficient and fast uAA incorporation. We demonstrate that GCEXpress can be used to efficiently alter the subcellular localization of proteins within living cells. We show that click labeling can resolve co-labeling problems of intercellular adhesive protein complexes. We apply this strategy to study the adhesion G protein-coupled receptor (aGPCR) ADGRE5/CD97 and its ligand CD55/DAF that play central roles in immune functions and oncological processes. Furthermore, we use GCEXpress to analyze the time course of ADGRE5-CD55 ligation and replenishment of mature receptor-ligand complexes. Supported by fluorescence recovery after photobleaching (FRAP) experiments our results show that ADGRE5 and CD55 form stable intercellular contacts that may support transmission of mechanical forces onto ADGRE5 in a ligand-dependent manner. We conclude that GCE in combination with biophysical measurements can be a useful approach to analyze the adhesive, mechanical and signaling properties of aGPCRs and their ligand interactions. This article is protected by copyright. All rights reserved.

Comparing ultrastable lasers at 7 × 10-17 fractional frequency instability through a 2220 km optical fibre network

Ultrastable lasers are essential tools in optical frequency metrology enabling unprecedented measurement precision that impacts on fields such as atomic timekeeping, tests of fundamental physics, and geodesy. To characterise an ultrastable laser it needs to be compared with a laser of similar performance, but a suitable system may not be available locally. Here, we report a comparison of two geographically separated lasers, over the longest ever reported metrological optical fibre link network, measuring 2220 km in length, at a state-of-the-art fractional-frequency instability of 7 × 10-17 for averaging times between 30 s and 200 s. The measurements also allow the short-term instability of the complete optical fibre link network to be directly observed without using a loop-back fibre. Based on the characterisation of the noise in the lasers and optical fibre link network over different timescales, we investigate the potential for disseminating ultrastable light to improve the performance of remote optical clocks.

A fine-tuned azobenzene for enhanced photopharmacology in vivo

Despite the power of photopharmacology for interrogating signaling proteins, many photopharmacological systems are limited by their efficiency, speed, or spectral properties. Here, we screen a library of azobenzene photoswitches and identify a urea-substituted "azobenzene-400" core that offers bistable switching between cis and trans with improved kinetics, light sensitivity, and a red-shift. We then focus on the metabotropic glutamate receptors (mGluRs), neuromodulatory receptors that are major pharmacological targets. Synthesis of "BGAG_12,400," a photoswitchable orthogonal, remotely tethered ligand (PORTL), enables highly efficient, rapid optical agonism following conjugation to SNAP-tagged mGluR2 and permits robust optical control of mGluR1 and mGluR5 signaling. We then produce fluorophore-conjugated branched PORTLs to enable dual imaging and manipulation of mGluRs and highlight their power in ex vivo slice and in vivo behavioral experiments in the mouse prefrontal cortex. Finally, we demonstrate the generalizability of our strategy by developing an improved soluble, photoswitchable pore blocker for potassium channels.

KCNE1 is an auxiliary subunit of two distinct ion channel superfamilies

Determination of what is the specificity of subunits composing a protein complex is essential when studying gene variants on human pathophysiology. The pore-forming α-subunit KCNQ1, which belongs to the voltage-gated ion channel superfamily, associates to its β-auxiliary subunit KCNE1 to generate the slow cardiac potassium I_Ks current, whose dysfunction leads to cardiac arrhythmia. Using pharmacology, gene invalidation, and single-molecule fluorescence assays, we found that KCNE1 fulfils all criteria of a bona fide auxiliary subunit of the TMEM16A chloride channel, which belongs to the anoctamin superfamily. Strikingly, assembly with KCNE1 switches TMEM16A from a calcium-dependent to a voltage-dependent ion channel. Importantly, clinically relevant inherited mutations within the TMEM16A-regulating domain of KCNE1 abolish the TMEM16A modulation, suggesting that the TMEM16A-KCNE1 current may contribute to inherited pathologies. Altogether, these findings challenge the dogma of the specificity of auxiliary subunits regarding protein complexes and questions ion channel classification.

(R)-Roscovitine and CFTR modulators enhance killing of multi-drug resistant Burkholderia cenocepacia by cystic fibrosis macrophages

Cystic fibrosis (CF) is characterized by chronic bacterial infections and heightened inflammation. Widespread ineffective antibiotic use has led to increased isolation of drug resistant bacterial strains from respiratory samples. (R)-roscovitine (Seliciclib) is a unique drug that has many benefits in CF studies. We sought to determine roscovitine’s impact on macrophage function and killing of multi-drug resistant bacteria. Human blood monocytes were isolated from CF (F508del/F508del) and non-CF persons and derived into macrophages (MDMs). MDMs were infected with CF clinical isolates of B. cenocepacia and P. aeruginosa. MDMs were treated with (R)-roscovitine or its main hepatic metabolite (M3). Macrophage responses to infection and subsequent treatment were determined. (R)-roscovitine and M3 significantly increased killing of B. cenocepacia and P. aeruginosa in CF MDMs in a dose-dependent manner. (R)-roscovitine-mediated effects were partially dependent on CFTR and the TRPC6 channel. (R)-roscovitine-mediated killing of B. cenocepacia was enhanced by combination with the CFTR modulator tezacaftor/ivacaftor and/or the alternative CFTR modulator cysteamine. (R)-roscovitine also increased MDM CFTR function compared to tezacaftor/ivacaftor treatment alone. (R)-roscovitine increases CF macrophage-mediated killing of antibiotic-resistant bacteria. (R)-roscovitine also enhances other macrophage functions including CFTR-mediated ion efflux. Effects of (R)-roscovitine are greatest when combined with CFTR modulators or cysteamine, justifying further clinical testing of (R)-roscovitine or optimized derivatives.

Migraine and Two-Pore-Domain Potassium Channels

Migraine is a common, disabling neurological disorder with a genetic, environmental, and hormonal component with an annual prevalence estimated at ~15%. It is characterized by attacks of severe, usually unilateral and throbbing headache, and can be accompanied by nausea, vomiting, and photophobia. Migraine is clinically divided into two main subtypes: migraine with aura, when it is preceded by transient neurological disturbances due to cortical spreading depression (CSD), and migraine without aura. Activation and sensitization of trigeminal sensory neurons, leading to the release of pro-inflammatory peptides, is likely a key component in headache pain initiation and transmission in migraine. In the present review, we will focus on the function of two-pore-domain potassium (K_2P) channels, which control trigeminal sensory neuron excitability and their potential interest for developing new drugs to treat migraine.

A (+)-Larixol Congener with High Affinity and Subtype Selectivity toward TRPC6

Natural products have many health benefits, and their application can improve the quality of life. Recently, the diterpene (+)-larixol and its acetylated congeners demonstrated selective inhibition of the second-messenger-gated cation channel transient receptor potential canonical 6 (TRPC6) over its close isoforms TRPC3 and TRPC7. Building on this knowledge, we expanded these findings by chemical diversification of (+)-larixol mostly at position C6. Implementing high-throughput Ca²⁺ FLIPR screening assays and electrophysiological patch-clamp recordings, we showcase larixyl N-methylcarbamate, termed SH045, as a compound with nanomolar affinity and 13-fold subtype selectivity over TRPC3 in stably expressing HEK293 cells. Expanding on this finding, TRPC6 inhibition was also observed in rat pulmonary smooth muscle cells. Furthermore, treatment of isolated perfused lung preparations with SH045 led to a decrease in lung ischemia-reperfusion edema (LIRE), a life-threatening condition associated with TRPC6 that may occur after organ transplantation. Taken together, and given the inexpensive, straightforward, and scalable preparation of SH045, we report a TRPC6 blocker that holds promise for the translational treatment of LIRE.

1.5 μm Lasers with Sub-10 mHz Linewidth

We report on two ultrastable lasers each stabilized to independent silicon Fabry-Pérot cavities operated at 124 K. The fractional frequency instability of each laser is completely determined by the fundamental thermal Brownian noise of the mirror coatings with a flicker noise floor of 4×10^{-17} for integration times between 0.8 s and a few tens of seconds. We rigorously treat the notorious divergences encountered with the associated flicker frequency noise and derive methods to relate this noise to observable and practically relevant linewidths and coherence times. The individual laser linewidth obtained from the phase noise spectrum or the direct beat note between the two lasers can be as small as 5 mHz at 194 THz. From the measured phase evolution between the two laser fields we derive usable phase coherence times for different applications of 11 to 55 s.

Justinus Kerner and mesmerism

Introduction

The German physician and poet Justinus Kerner (1786–1862), Swabian public health officer in Weinsberg, is well known as an allround, even an epoch-making personality in his time and a natural scientist typical for late romanticism. His greatest merit is not due to his poetic scripts, but to his scientific work. This begins with his medical dissertation “Observata de functione singularum partium auris”, a mine of experimental behaviourism.

Objectives

The aim of this study is to evaluate the influence of Franz Anton Mesmer (1734–1815) on Kerner's way of treating patients.

Methods

A literature research was done on Kerner and mesmerism.

Results

Kerner's first contact with animal magnetism was in 1797, when he was magnetized and healed by Dr. Eberhard Gmelin, one of the first mesmerian doctors in Germany, because of his nervous stomach. With the “Seeress of Prevorst” the author ventured to advance into deep layers of the soul unknown so far. During the years 1826–1829 Justinus Kerner treated Friederike Hauffe (1801–1829), the “Seeress of Prevorst”, at his Weinsberg domicile. In the year 1829 he published the description of her life and disease with the title “The Seeress of Prevorst, being revelations concerning the inner-life of man, and the interdiffusion of a world of spirits in the one we inhabit”.

Conclusions

Kerner was very much influenced by Mesmer and left volumes of psycho-pathological case histories that helped to prepare a way for a medicine more psychotherapeutically founded.

Disclosure of interest

The author has not supplied his/her declaration of competing interest.

Transportable Optical Lattice Clock with 7×10^{-17} Uncertainty

We present a transportable optical clock (TOC) with ^{87}Sr. Its complete characterization against a stationary lattice clock resulted in a systematic uncertainty of 7.4×10^{-17}, which is currently limited by the statistics of the determination of the residual lattice light shift, and an instability of 1.3×10^{-15}/sqrt[τ] with an averaging time τ in seconds. Measurements confirm that the systematic uncertainty can be reduced to below the design goal of 1×10^{-17}. To our knowledge, these are the best uncertainties and instabilities reported for any transportable clock to date. For autonomous operation, the TOC has been installed in an air-conditioned car trailer. It is suitable for chronometric leveling with submeter resolution as well as for intercontinental cross-linking of optical clocks, which is essential for a redefinition of the International System of Units (SI) second. In addition, the TOC will be used for high precision experiments for fundamental science that are commonly tied to precise frequency measurements and its development is an important step to space-borne optical clocks.

A clock network for geodesy and fundamental science

Leveraging the unrivalled performance of optical clocks as key tools for geo-science, for astronomy and for fundamental physics beyond the standard model requires comparing the frequency of distant optical clocks faithfully. Here, we report on the comparison and agreement of two strontium optical clocks at an uncertainty of 5 × 10⁻¹⁷ via a newly established phase-coherent frequency link connecting Paris and Braunschweig using 1,415 km of telecom fibre. The remote comparison is limited only by the instability and uncertainty of the strontium lattice clocks themselves, with negligible contributions from the optical frequency transfer. A fractional precision of 3 × 10⁻¹⁷ is reached after only 1,000 s averaging time, which is already 10 times better and more than four orders of magnitude faster than any previous long-distance clock comparison. The capability of performing high resolution international clock comparisons paves the way for a redefinition of the unit of time and an all-optical dissemination of the SI-second.

Comparing the frequency of two distant optical clocks will enable sensitive tests of fundamental physics. Here, the authors compare two strontium optical-lattice clocks 690 kilometres apart to a degree of accuracy that is limited only by the uncertainty of the individual clocks themselves.

Injectable microcarriers as human mesenchymal stem cell support and their application for cartilage and degenerated intervertebral disc repair

Degeneration of the intervertebral disc (IVD) is a progressive and chronic process, and the high incidence of discogenic disorders calls for new therapeutic approaches, such as cell-based therapies using three dimensional cultures and mesenchymal stem cells (MSC), which can differentiate to chondrogenic- and IVD-lineages. Here, we investigated the growth and differentiation of human MSC culture on biodegradable collagen scaffolds in order to obtain an injectable suspension. Commercially available wound dressings were downsized to dimensions between 100 and 1500 μm and seeded with freshly isolated or early passages MSC. Proliferation rate and chondrogenic differentiation potential was tested at oxygenation levels of 2%, 5%, 10% and 21% in static and dynamic cultures. Evaluation methods included cell viability test, disc marker genes expression (aggrecan, collagen type I and type II), histological detection of proteoglycans and immunohistochemical analysis. On microcarriers, freshly isolated MSC had lower proliferation rate and chondrogenic differentiation potential compared with early passages MSC. Proliferation of MSC was significantly increased 1.7-fold at 5% oxygen level and in combination with dynamic culture was further increased to 2.3-fold, with respect to normoxia. Chondrogenesis was positively affected by 2% and 5% hypoxia, as shown by increased transcription levels and protein expression of collagen type II and proteoglycan accumulation in static cultures, while it was inhibited in dynamic cultures. Collagen type I and aggrecan expression were not affected by hypoxia. In conclusion, collagen based microcarriers are a suitable support for in vitro MSC growth and chondrogenesis especially when cultured at 5% oxygen level.

Observation of Efimov resonances in a mixture with extreme mass imbalance

We observe two consecutive heteronuclear Efimov resonances in an ultracold Li-Cs mixture by measuring three-body loss coefficients as a function of magnetic field near a Feshbach resonance. The first resonance is detected at a scattering length of a_((0))=-320(10)a_((0)), corresponding to ∼7(∼3) times the Li-Cs (Cs-Cs) van der Waals range. The second resonance appears at 5.8(1.0)a_((0)), close to the unitarity-limited regime at the sample temperature of 450 nK. Indication of a third resonance is found in the atom loss spectra. The scaling of the resonance positions is close to the predicted universal scaling value of 4.9 for zero temperature. Deviations from universality might be caused by finite-range and temperature effects, as well as magnetic field-dependent Cs-Cs interactions.

How much does it hurt to be lonely? Mental and physical differences between older men and women in the KORA-Age Study

OBJECTIVE

Loneliness has a deep impact on quality of life in older people. Findings on sex-specific differences on the experience of loneliness remain sparse. This study compared the intensity of and factors associated with loneliness between men and women.

METHODS

Analyses are based on the 2008/2009 data of the KORA-Age Study, comprising 4127 participants in the age range of 64-94 years. An age-stratified random subsample of 1079 subjects participated in a face-to-face interview. Loneliness was measured by using a short German version of the UCLA-Loneliness-Scale (12 items, Likert scaled, ranging from 0 to 36 points). Multiple logistic regression analysis was conducted to analyze the associations of socio-demographic, physical, and psychological factors with loneliness.

RESULTS

The mean level of loneliness did not significantly differ between men (17.0 ± 4.5) and women (17.5 ± 5.1). However, among the oldest old (≥85 years), loneliness was higher in women (p value = 0.047). Depression, low satisfaction with life, and low resilience were associated significantly with loneliness, which was more pronounced in men. Living alone was not associated with loneliness, whereas lower social network was associated with a three time higher risk for feeling lonely in both men and women.

CONCLUSIONS

The extent of loneliness was equally distributed between men and women, although women were more disadvantaged regarding living arrangements as well as physical and mental health. However, loneliness was stronger associated with adverse mental health conditions in men. These findings should be considered when developing intervention strategies to reduce loneliness.

[Friedrich Schiller and Psychosomatics from the Perspective of Recent Research]

RESEARCH QUESTION

The aim of this study is to show that Friedrich Schiller (1759 - 1805) was very early in life inclined towards psychosomatic interactions.

MATERIAL AND METHODS

An analysis of the secondary literature since the death of Friedrich Schiller for the subjects "Friedrich Schiller" and "psychosomatics" was undertaken.

RESULTS

Already during his medical studies at the "Hohe Karlsschule" in Stuttgart (Germany) Schiller studied very intensively psychosomatic issues on account of the disease of another student, Joseph Frédéric Grammont, and included the topic in his three theses. Not inclined to practical work as a physician, there are many psychosomatic thoughts and medical concepts in his writings, especially in the play "Die Räuber" (1781) and in "Don Carlos, Infant von Spanien" (1787). Towards the then upcoming topic mesmerism he remained very sceptic. In coping with his own illness there are many psychosomatic aspects, too. Despite his own severe somatic illness he could cope with pain and emphasised in his writings the importance of the freedom of anxiety before death.

Hypertension and depressed symptomatology: a cluster related to the activation of the renin-angiotensin-aldosterone system (RAAS). Findings from population based KORA F4 study

CONTEXT

Preliminary evidence points to aldosterone being not only prominently involved in the systemic regulation of the blood pressure but also to play a role in the pathophysiology of depression.

OBJECTIVE

We evaluated whether the combination of hypertension and depressed symptomatology is useful to screen for individuals suffering an activation of the renin-angiotensin-aldosterone system (RAAS).

DESIGN

We conducted a cross-sectional analysis in participants from the Cooperative Health Research in the Region of Augsburg (KORA) F4 Study conducted between 2006 and 2008 in Southern Germany. A total of 1805 participants of the F4 study were included in the study.

METHODS

The association between aldosterone and renin levels and the different combinations of hypertension and depressed symptomatology was examined in four different models of multiple linear regression adjusted for age, sex, creatinine levels, potassium levels, body mass index (BMI) and behavioural risk factors.

RESULTS

Individuals suffering both, depressed symptomatology and hypertension exhibited highly significantly increased aldosterone levels (p<0.001) and slightly, not significantly increased renin levels (p=0.08) compared to individuals with no depressed symptomatology and no hypertension. No significant activation of the RAAS was seen in only depressed or only hypertensive individuals.

CONCLUSIONS

The finding of highly significantly increased aldosterone levels and increased renin levels in individuals suffering both, depressed symptomatology and hypertension provides further evidence for the involvement of the RAAS in the pathogenesis of depressed symptomatology. These findings have important implications for future research concerning the pathophysiological pathways that link depression and cardiovascular disease.

To live alone and to be depressed, an alarming combination for the renin-angiotensin-aldosterone-system (RAAS)

INTRODUCTION

The renin-angiotensin-aldosterone-system (RAAS) is one of the most important systems involved in the pathogenesis of cardiovascular diseases. Its role in stress response has been generally neglected, although the progression of cardiovascular disease is considerably increased in the presence of stress and especially in the presence of depression risk. With the present analysis we aimed to evaluate whether the activity of the RAAS correlates with depressive symptomatology and with chronic stress. Moreover, we aimed to analyse whether stress response is altered in the presence of depressed symptomatology. We chose "living alone" to be our paradigm of chronic stress.

METHODS AND RESULTS

Aldosterone and renin levels were assessed in 1743 (829 men, 914 women) from the population-based KORA study (Cooperative Health Research in the Region of Augsburg). The relationship between aldosterone, renin levels and the different combinations of living alone and depressive symptomatology was examined in three different multiple linear regression models adjusted for age, sex, creatinine levels, potassium levels, body mass index (BMI) and bio-behavioural factors. Neither "living alone" nor depressive symptomatology alone were associated with an activation of the RAAS, but the combination of living alone and depressive symptomatology yielded a highly significant increase in the aldosterone (p<0.01) and renin level (p=0.03).

CONCLUSION

Our findings show that depressive symptomatology is associated with a hyper-responsiveness to chronic stress. Under the condition of chronic stress depressed individuals have an activated RAAS. Activation of the RAAS might explain the known increased risk of negative cardiovascular disease outcomes in this group.

Association between social isolation and inflammatory markers in depressed and non-depressed individuals: results from the MONICA/KORA study

INTRODUCTION

Depressed individuals not only suffer from chronic low grade inflammation, but also exhibit an inflammatory hyper-responsiveness to acute stress. We investigate whether chronic stress also induces an exaggerated inflammatory response in individuals with increased depression features. As model for chronic stress, social isolation was chosen.

METHODS

Interleukin (IL)-6 and hs-CRP levels were assessed in 1547 subjects (847 men and 700 women), derived from the population-based MONICA/KORA study. Standardized questionnaires were used to assess depressed mood (depression and exhaustion subscale) and social isolation (social network index). The relationship between the two inflammatory markers, social isolation and depressed mood was examined taking into account interactions social isolation × depressed mood using multivariable linear regression models, adjusted for age, BMI, smoking, alcohol, and physical activity. Analyses were performed in men and women separately.

RESULTS

We observed a significant interaction between depressed mood and social isolation regarding IL-6 and hs-CRP, respectively in men (p-value=0.02 for IL-6 and <0.01 for hs-CRP), evidencing a substantial synergistic effect of social isolation, and depressed mood on inflammatory responses. Furthermore, depressed and socially isolated men had highly significantly elevated IL-6 levels (geometric mean: 3.76 vs. 1.92 pg/ml, p-value <0.01) and heightened hs-CRP levels (geometric mean: 2.01 vs. 1.39 mg/l, p=0.08) in comparison with non-depressed and socially integrated men. In women, no significant associations were seen.

CONCLUSION

The interaction of depressed mood and social isolation elicits a substantial synergistic impact on inflammatory markers in men, but not in depressed women.

Sleep disturbances and depressed mood: a harmful combination associated with increased leptin levels in women with normal weight

Leptin, involved in energy regulation and contributor to cardiovascular disease, has been implicated to play a role in depression and sleep disturbances, two closely intertwined conditions. Previous results investigating leptin level alterations either in sleep disorders or in depression have been inconsistent. We investigate the association between leptin levels and the different combinations of depressed mood and sleep disturbances in 1369 subjects (706 men, 663 women), derived from the population-based MONIKA/KORA study. As leptin regulation is known to differ by sex and weight, analyses were performed in normal weight and overweight men and women separately. We found a highly significant association between leptin levels and the combination of depressed mood and sleep disturbances in normal-weight women (BMI ≤ 25) (p<0.01). No associations were found in men and in overweight women. Our results suggest that leptin regulation in depressed mood and sleep disturbances very much depend on sex and weight.

[Depression. An underestimated risk for the development and progression of coronary heart disease]

The aim of this article is to provide an overview on depression as a risk factor for the onset and follow-up of cardiovascular disease (CVD). In brief, the current state of psychobiological mechanisms bridging the gap between affective states and somatic consequences are presented. Four meta-analyses dealing with depression as a CVD risk factor in apparently healthy populations with >100,000 participants included, extracted an adjusted effect estimator of 1.60-1.90. Depressed subjects present with an unhealthier lifestyle (nutrition, smoking, physical activity). Three major psychobiological pathways directly acting on the circulatory system are under discussion: (1) hyperregulation of the autonomic nervous system (e.g., increased mean heart rate, increased heart rate responses, impaired heart rate variability), (2) overshooting stress responses of the endocrine system with impaired feedback mechanisms (e.g., for cortisol release), and (3) the immune system with dysregulated release of acute phase proteins and proinflammatory cytokines, all involved in a bidirectional crosstalk with the patient's affective state and leading to platelet activation and flow mediated endothelial (dys-)function. Nonadherence and adverse side effects of medications also contribute to the lethal properties of depression in CVD.

Social isolation and depressed mood are associated with elevated serum leptin levels in men but not in women

BACKGROUND

Leptin, involved in energy homeostasis and a predictor of cardiovascular disease, has recently been recognized as mediator in stress reactions. We aimed to explore the association between leptin levels and two stress-related conditions, social isolation and depressed mood, both associated with increased cardiovascular mortality.

METHODS

We analysed leptin levels in 1229 subjects (643 men, 586 women), derived from the population-based MONIKA/KORA study. Standardized questionnaires were used to assess depressive mood and social isolation. In a multiple linear regression adjusted for body weight, age and survey, the association between leptin, social isolation and depressed mood and its interaction was explored in men and women separately. Leptin was then dichotomized and four analyses, adjusted for age, BMI, lifestyle factors, psychosomatic complaints and metabolic variables were performed to compare the risk of elevated leptin levels in the risk groups.

RESULTS

Increased leptin levels were associated with social isolation (p=0.04) and the interaction between social isolation and depressed mood (p=0.02) in men but not in women. In socially isolated and depressed men, leptin levels (mean: 6.07 ng/ml) were significantly increased compared to neither depressed nor isolated men (mean: 4.51 ng/ml, p=0.04). In the multivariate adjusted logistic regression model, the combination of depressed state and social isolation was associated with a 4-fold increased risk (p<0.001) for elevated leptin levels.

CONCLUSION

The finding of elevated leptin levels in socially isolated and depressed men raises the possibility that increased cardiovascular mortality in socially isolated men is partially mediated by hyperleptinemia.

[Immanuel Kant--a genius of pedantry and punctuality]

The German philosopher Immanuel Kant (22.4.1724 - 12.2.1804), who formulated the ideal of man lead by consciousness, had a peculiar personality and suffered from many somatic complaints. Nevertheless his ritualized way of living determined by many rules and ritualized lunch seems to be a resource that enabled a great and epoch-making work despite his physical weakness. His "maximized" way of living seems to have had no negative consequences either on his work or on his life. It seems that it made his work and life very agreeable and contributed to the legendary calm and regularity he appreciated so much. Kant's character was specified by his "constant pursuit for intellectually well-founded principles in every manner" - at least according to his persuasion. So his compulsive personality traits seem to be a necessary condition for his work.

[Psychic symptoms and mental health service utilisation--an epidemiologic study in the city of Stuttgart]

A newly developed questionnaire has been administered to the children and their parents during the medical examination of the school doctors of the local board of public health. The 40-item questionnaire asks for sociodemographic data (age, gender, nationality, brothers and sisters), height, weight, psychic symptoms for the prevalence period of the last seven days and the last month, alcohol, nicotine and drug abuse, medication, eating behavior and delinquency. The questionnaire for parents additionally asks if the child has been in psychotherapy during the last twelve months and if parents think that there are enough treatment facilities that are easily available. As it takes only about five to eight minutes to answer the questionnaire the acceptance has been very good. 481 pupils from eleven primary schools in ten sections of the city of Stuttgart (Germany) could be included. Answering the questionnaire could quite easily be integrated in the medical examinations of the school doctors of the local board of public health. The most common complaints of the pupils for the last seven days were feelings of inner restlessness (24.0%), difficulties in falling asleep (22.5%), headaches (20.8%), stomachaches or cramps (19.6%) and nervousness (18.5%). Alcohol and nicotine abuse were not relevant in this age group. The treatment rate during the last 12 months has been 4.4% and the utilisation of mental health services has been considered by 4.2% of the parents during this period. Only 25.8% of non-German parents think that the care provision is sufficient. The substantial unfulfilled mental health needs of the pupils should have consequences for service planning.

[Indications for inpatient psychotherapy. When does your patient belong in a clinic?]

Institutionalized psychotherapy is indicated for specific disorders, the treatment of which at certain times or phases cannot be implemented in the doctor's office. Further Indications are patient denial and lack of motivation, a need to remove the patient from a pathogenic environment, a need for outpatient treatment initiation, and, in selected patients, a crisis situation, when the symptoms become acute or when internistic reasons are present. When these positive indication criteria apply--apart from emergency and crisis situations--a mental and somatic pre-evaluation--best done by the admitting institution--should be part of the pre-diagnostic work-up.

[Not Available]

Since the epoch-making publication of Sir Francis Galton, twin research has been an excellent method in order to assess the influence of nature and nurture. In this overview the history of twin research is described for the field of psychogenic disorders by the examples of diagnosis of zygosity, representativity of the sample, criminality, homosexuality and some disorders such as enuresis, obsessive-compulsive disorders and anorexia nervosa. Nowadays the modern methods of molecular genetics for diagnosis of zygosity offer new and overwhelming possibilities of twin research.

Identification and characterization of a novel hsc70-like gene in the human lung tumor cell line HS24

We determined the cDNA sequence and analyzed the genomic structure of a novel human gene designated HS24/p52, which shows significant similarity to the ATP-binding domain of stress-70 proteins in the human lung tumor cell line HS24. The 2,203-nucleotide-long cDNA sequence is divided into an incomplete 10-nucleotide 5' nontranslated region, a 1,425-nucleotide open reading frame which codes for 474 amino acids and a 768-nucleotide 3' nontranslated region. The first 404 of the deduced 474 amino acids resemble the amino-terminal regions of Hsp70 proteins from different species. Furthermore, single amino acid and short amino acid stretches, which are thought to be essential for the ATPase mechanism and ATP-binding activity in Hsp70 proteins, are conserved in this sequence, too. The carboxy-terminal 70 amino acids exhibit no significant similarity to hsp70 nor to any other known protein sequences. The HS24/p52 gene contains at least five introns, which differ significantly from hsc70 genes with regard to their size and location within the coding sequences. The total size of this gene is more than 15 kbp. Polymerase chain reaction (PCR) experiments showed that this gene is expressed in different human cell lines and tissues and it also seems to be highly conserved between human and mouse.

Mechanism of inhibition of Raf-1 by protein kinase A

The cytoplasmic Raf-1 kinase is essential for mitogenic signalling by growth factors, which couple to tyrosine kinases, and by tumor-promoting phorbol esters such as 12-O-tetradecanoylphorbol-13-acetate, which activate protein kinase C (PKC). Signalling by the Raf-1 kinase can be blocked by activation of the cyclic AMP (cAMP)-dependent protein kinase A (PKA). The molecular mechanism of this inhibition is not precisely known but has been suggested to involve attenuation of Raf-1 binding to Ras. Using purified proteins, we show that in addition to weakening the interaction of Raf-1 with Ras, PKA can inhibit Raf-1 function directly via phosphorylation of the Raf-1 kinase domain. Phosphorylation by PKA interferes with the activation of Raf-1 by either PKC alpha or the tyrosine kinase Lck and even can downregulate the kinase activity of Raf-1 previously activated by PKC alpha or amino-terminal truncation. This type of inhibition can be dissociated from the ability of Raf-1 to associate with Ras, since (i) the isolated Raf-1 kinase domain, which lacks the Ras binding domain, is still susceptible to inhibition by PKA, (ii) phosphorylation of Raf-1 by PKC alpha alleviates the PKA-induced reduction of Ras binding but does not prevent the downregulation of Raf-1 kinase activity by PKA and (iii) cAMP agonists antagonize transformation by v-Raf, which is Ras independent.

[Georg Groddeck--father of psychosomatic medicine]

Life and work of Georg Groddeck (1866-1934), a nearly forgotten pioneer of psychosomatic medicine, are presented. Special emphasis is laid on the term "Es" and its impacts on putting forward psychoanalytic theories as well as the relationship to Sigmund Freud. The influence of Groddeck on the development of psychoanalysis and his friendship with Sándor Ferenczi are rendered prominent. Finally, the value of Groddeck's ideas for the future of psychosomatic medicine is discussed.

CSF pharmacokinetics of ceftazidime in neurosurgical patients with an external ventriculostomy

In 11 neurosurgical patients (seven women, four men, aged 22-73 years) undergoing external ventriculostomy, serum and cerebrospinal fluid (CSF) pharmacokinetics of ceftazidime (CAZ) administered as a chemoprophylactic agent were evaluated. Concentrations of CAZ in CSF correlated significantly (p less than 0.05) with serum concentrations and with leucocyte counts in CSF. Peak concentrations in CSF (range 0-25.5 mg/l) exceeded the MIC90 of Staphylococcus species in two and of Pseudomonas and Enterobacter species in five of 11 patients. The MIC90 values of the other relevant bacteria causing CNS infections in these patients were surpassed in nine of 11 patients.

Hypothalamo-pituitary-gonadal axis in children with chronic renal failure

Delayed puberty in children with chronic renal failure (CRF) may be due to gonadal dysfunction, increased plasma binding of gonadal hormones, or changes of the hypothalamo-pituitary axis. Plasma androgens were studied in 17 prepubertal boys with preterminal CRF. In addition, the response of luteinizing and follicle-stimulating hormones (LH, FSH) to luteinizing-releasing hormone (LHRH) was followed in the plasma of these boys and of 12 prepubertal girls with CRF. Plasma testosterone (T) was significantly lower in the CRF boys than it was in the controls (mean, 9 vs. 22 ng/ml) and concerned also the free T fraction (2.5% in both groups). Dihydro-T was similarly reduced in CRF, resulting in a normal T/DHT ratio. Basal plasma LH levels were significantly elevated in boys (1.0 vs. 0.5 ng/ml) and in girls with CRF (1.4 vs. 0.4 ng/ml), whereas mean basal FSH values were similar to controls. After LHRH administration, peak levels of LH and FSH were not different in CRF and control children; however, the absolute differences from basal to peak values were lower in CRF. These findings may indicate that Leydig cell dysfunction in CRF already occurs before the onset of puberty. The blunted LH and FSH responses to LHRH suggest an additional disturbance at the hypothalamo-pituitary level.