Mesoscopic Structure of Lipid Nanoparticle Formulations for mRNA Drug Delivery: Comirnaty and Drug-Free Dispersions

Lipid nanoparticles (LNPs) produced by antisolvent precipitation (ASP) are used in formulations for mRNA drug delivery. The mesoscopic structure of such complex multicomponent and polydisperse nanoparticulate systems is most relevant for their drug delivery properties, medical efficiency, shelf life, and possible side effects. However, the knowledge on the structural details of such formulations is very limited. Essentially no such information is publicly available for pharmaceutical dispersions approved by numerous medicine agencies for the use in humans and loaded with mRNA encoding a mimic of the spike protein of the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) as, e.g., the Comirnaty formulation (BioNTech/Pfizer). Here, we present a simple preparation method to mimic the Comirnaty drug-free LNPs including a comparison of their structural properties with those of Comirnaty. Strong evidence for the liquid state of the LNPs in both systems is found in contrast to the designation of the LNPs as solid lipid nanoparticles by BioNTech. An exceptionally detailed and reliable structural model for the LNPs i.a. revealing their unexpected narrow size distribution will be presented based on a combined small-angle X-ray scattering and photon correlation spectroscopy (SAXS/PCS) evaluation method. The results from this experimental approach are supported by light microscopy, 1H NMR spectroscopy, Raman spectroscopy, cryogenic electron microscopy (cryoTEM), and simultaneous SAXS/SANS studies. The presented results do not provide direct insights on particle formation or dispersion stability but should contribute significantly to better understanding the LNP drug delivery process, enhancing their medical benefit, and reducing side effects.

POS0684 IS UPADACITINIB CAPABLE OF IMPROVING PATIENT-REPORTED OUTCOMES OF RHEUMATOID ARTHRITIS IN A REAL-WORLD SETTING? RESULTS FROM THE POST-MARKETING OBSERVATIONAL UPwArds STUDY

Background

The efficacy of Upadacitinib (UPA), a selective Janus kinase inhibitor, has been evaluated in the SELECT clinical program 1-6. In addition, recent results from the non-interventional UPwArds study further confirmed UPAs clinical effectiveness regarding standard disease activity scores for rheumatoid arthritis (RA) in a real-world setting 7. However, patient-reported outcomes (PROs) as another cornerstone of clinical decision making yet remain to be addressed in the context of a post-marketing setting. This interim analysis, conducted after 250 patients had completed the 6-month follow-up visit, aims to fill this gap.

Objectives

To evaluate the change of selected PROs over 6 months in patients treated with UPA in a real-world data environment.

Methods

UPwArds is a prospective, open-label, multicenter, non-interventional, post-marketing study including adult patients with moderate-to-severe RA (swollen joint count [SJC28] ≥ 3 and inadequate response or intolerance to at least one previous disease-modifying antirheumatic drug). According to the German label, patients were treated with UPA 15 mg once daily, as monotherapy or in combination with methotrexate. For this analysis, the following PROs were included: 0-10 numerical rating scales (NRS) for pain and fatigue, the Health Assessment Questionnaire Disability Index (HAQ-DI), the duration and severity of morning stiffness, the Patient Health Questionnaire 9 (PHQ-9), and the Rheumatoid Arthritis Impact of Disease Questionnaire (RAID). Changes from baseline were evaluated for follow-up periods of 1 month, 3 months, and 6 months. Results are presented for the total sample using descriptive measures reflecting sample size (N), average values (standard deviation) for each assessment and average change scores (standard deviation) for follow-up visits. All data were analyzed as observed, with no imputation of missing data.

Results

483 patients (369 female, 114 male) were included in the study, with available baseline PRO information for 481 patients. 6-months follow-up data were yet available from 279 patients The baseline average age and disease duration were 58.0 (12.3) years and 9.0 (8.0) years, respectively, whereas the mean initial DAS28-CRP was 4.6 (1.0). At baseline, 60.8% of enrolled patients had previously been treated with biologic or targeted synthetic disease-modifying antirheumatic drugs. Overall, PRO scores improved from baseline throughout month 6 with a considerable amelioration at month 3, which was maintained at month 6. Responses were rapid, with improvement already evident at month 1 (Table 1). The NRS pain as a crucial PRO in RA confirmed the previously described pattern of results seen for most of the other PROs (Figure 1).

Table 1.

Baseline scores and average changes from baseline scores

NBaseline scores (SD)NChange from baseline - month 1 (SD)NChange from baseline - month 3 (SD)NChange from baseline - month 6(SD)Pain (NRS)4816.2 (2.2)393-2.2 (2.3)392-2.5 (2.5)258-2.4 (2.4)Fatigue (NRS)4815.5 (2.6)393-1.4 (2.3)393-1.6 (2.4)259-1.5 (2.3)HAQ-DI4711.3 (0.6)380-0.2 (0.3)376-0.2 (0.4)253-0.2 (0.4)Morning stiffness (duration, minutes)43968.9 (63.9)313-25.0 (55.3)296-29.6 (54.9)179-31.6 (51.7)Morning stiffness (severity)4785.2 (2.7)386-1.8 (2.3)393-2.2 (2.6)258-2.2 (2.9)PHQ-94778.7 (5.2)383-1.9 (3.9)381-2.3 (4.0)255-2.2 (3.8)RAID4815.6 (2.0)393-1.7 (1.8)392-2.0 (2.0)258-1.9 (1.9)

Conclusion

This interim analysis confirmed a meaningful improvement regarding included PROs that cover various RA-related symptoms, depressiveness and the impact of symptoms of RA on daily life.

References

[1]Smolen JS, et al. Lancet 2019;393:2303–11

[2]Burmester GR, et al. Lancet 2018;391:2503–12

[3]Genovese MC, et al. Lancet 2018;391:2513–24

[4]van Vollenhoven R, et al. Arthritis Rheumatol 2020;72:1607–20

[5]Fleischmann R, et al. Arthritis Rheumatol 2019;71:1788–800

[6]Rubbert-Roth A, et al. N Engl J Med 2020;383:1511–21

[7]Witte T et al. P0833 at ACR, Nov 5–9, 2021

Acknowledgements

AbbVie funded this study; contributed to its design; participated in data collection, analysis, and interpretation of the data; and in the writing, review, and approval of the abstract. AbbVie and the authors thank all study investigators for their contributions and the patients who participated in this study. No honoraria or payments were made for authorship. The medical writing support was provided by Matthias Englbrecht, Freelance Healthcare Data Scientist (Eckental, Germany) and was funded by AbbVie. Statistical analyses were provided by Dr. Daniela Adolf of StatConsult GmbH (Magdeburg, Germany) which was funded by AbbVie.

Disclosure of Interests

Torsten Witte Grant/research support from: AbbVie, Amgen, Bristol-Myers Squibb, Celgene, Chugai, Gilead, Janssen, Lilly, MSD, Mylan, Novartis, Pfizer, Roche, and UCB, Uta Kiltz Consultant of: AbbVie, Biocad, Eli Lilly and Company, Grünenthal, Hexal, Janssen, MSD, Novartis, Pfizer, Roche, and UCB, Grant/research support from: AbbVie, Amgen, Biogen, Fresenius, GSK, Hexal, Novartis, and Pfizer, Florian Haas Consultant of: AbbVie, Celgene, Novartis, and Pfizer, Grant/research support from: AbbVie, BMS, Celgene, Chugai, MSD, Novartis, Pfizer, Roche, and Sanofi Genzyme, Elke Riechers Consultant of: AbbVie, Chugai, Novartis, and UCB, Grant/research support from: AbbVie, Chugai, Lilly, Janssen, Novartis, Pfizer, Roche, and UCB, Ulrich Prothmann Grant/research support from: AbbVie, Amgen, Bristol-Myers Squibb, Chugai, Glaxo Smith Kline, Novartis, Pfizer, Roche, Sanofi, SOBI, and UCB, Daniela Adolf Shareholder of: Employee of StatConsult and may own stock or options, Employee of: Employee of StatConsult, Carsten Holland Shareholder of: Employee of AbbVie and may own stock or options, Employee of: Employee of AbbVie, Alexander Roessler Shareholder of: Employee of AbbVie and may own stock or options, Employee of: Employee of AbbVie, Kirsten Famulla Shareholder of: Employee of AbbVie and may own stock or options, Employee of: Employee of AbbVie, Konrad Götz Shareholder of: Employee of AbbVie and may own stock or options, Employee of: Employee of AbbVie, Klaus Krueger Grant/research support from: AbbVie, Biogen, BMS, Celltrion, Gilead, Hexal, Janssen, Lilly, Medac, MSD, Novartis, Pfizer, Roche, and UCB

A novel experimental approach for nanostructure analysis: simultaneous small-angle X-ray and neutron scattering

Exploiting small-angle X-ray and neutron scattering (SAXS/SANS) on the same sample volume at the same time provides complementary nanoscale structural information in two different contrast situations. Unlike an independent experimental approach, the truly combined SAXS/SANS experimental approach ensures the exactness of the probed samples, particularly for in situ studies. Here, an advanced portable SAXS system that is dimensionally suitable for installation in the D22 zone of ILL is introduced. The SAXS apparatus is based on a Rigaku switchable copper/molybdenum microfocus rotating-anode X-ray generator and a DECTRIS detector with a changeable sample-to-detector distance of up to 1.6 m in a vacuum chamber. A case study is presented to demonstrate the uniqueness of the newly established method. Temporal structural rearrangements of both the organic stabilizing agent and organically capped gold colloidal particles during gold nanoparticle growth are simultaneously probed, enabling the immediate acquisition of correlated structural information. The new nano-analytical method will open the way for real-time investigations of a wide range of innovative nanomaterials and will enable comprehensive in situ studies on biological systems. The potential development of a fully automated SAXS/SANS system with a common control environment and additional sample environments, permitting a continual and efficient operation of the system by ILL users, is also introduced.

Internal Structure of Nanometer-Sized Droplets Prepared by Antisolvent Precipitation

Antisolvent precipitation (AP) is a low-cost and less-invasive preparation alternative for organic nanoparticles compared to top-down methods such as high-pressure homogenization or milling. Here we report on particularly small organic nanoparticles (NPs) prepared by AP. It has been found for various materials that these NPs in their liquid state exhibit a significant degree of molecular order at their interface toward the dispersion medium including ubiquinones (coenzyme Q10), triglycerides (trimyristin, tripalmitin), and alkanes (tetracosane). This finding is independent of the use of a stabilizer in the formulation. While this is obviously a quite general interfacial structuring effect, the respective structural details of specific NPs systems might differ. Here, a detailed structural characterization of very small liquid coenzyme Q10 (Q10) NPs is presented as a particular example for this phenomenon. The Q10 NPs have been prepared by AP in the presence of two different stabilizers, sodium dodecyl sulfate (SDS) and pentaethylene glycol monododecyl ether (C₁₂E₅), respectively, and without any stabilizer. The NPs' size is initially analyzed by photon correlation spectroscopy (PCS). The SDS-stabilized Q10 NPs have been studied further by differential scanning calorimetry (DSC), small-angle X-ray and neutron scattering (SAXS, SANS), wide-angle X-ray scattering (WAXS), and cryogenic transmission electron microscopy (CryoTEM). A simultaneous analysis of SAXS and contrast variation SANS studies revealed the molecular arrangement within the interface between the NPs and the dispersion medium. The Q10 NPs stabilized by SDS and C₁₂E₅, respectively, are small (down to 19.9 nm) and stable (for at least 16 months) even when no stabilizer is used. The SDS-stabilized Q10 NPs reported here, are therewith, to the best of our knowledge, the smallest organic NPs which have been reported to be prepared by AP so far. In particular, these NPs exhibit a core-shell structure consisting of an amorphous Q10 core and a surrounding shell, which is mainly composed of oriented Q10 molecules and aligned SDS molecules. This structure suggests a significant amphiphilic behavior and a rather unexpected stabilizing role of Q10 molecules.

[What do medical students think of family medicine? Results of an online cross-sectional study in the federal state of Baden-Wuerttemberg]

BACKGROUND

In the context of physician shortages, critical factors influencing career choice need to be better understood. The aim of this study was to explore experiences students have had with family medicine in order to develop additional strategies for recruiting family medicine trainees.

METHODS

Students from the five medical faculties in the federal state of Baden-Wuerttemberg were invited to participate in an online-survey via email. A purpose-built questionnaire was used. In addition to descriptive statistics, analysis included linear partial correlations controlled for age, gender, and semester, which were calculated between the variable "I believe family medicine is an attractive job" and the 31 variables of the survey. Linear regression was used to analyze the influence of experiences with family medicine and statements about family medicine to the perception of family medicine as an attractive specialty.

RESULTS

1299 students participated in the survey. About half of the participants (49.7 %) considered working as a primary care physician to be attractive or partly attractive. 49.6 % of students reported positive experiences with family medicine as a patient and 33.1 % as a family member. 24.3 % reported positive experiences during the compulsory 1-2 weeks general practice internship and 18.1 % during a four weeks elective placement. For 302 participants (23.3 %), family medicine is presented positively in the media. 178 (13.7 %) consider family medicine to have high importance in both undergraduate and postgraduate education. Positive influences on judging attractiveness of family medicine were: own experience with family medicine as a clinical elective (rpart= + 0.450), own experience with family medicine as a patient (rpart= + 0.218), perception that family medicine offers a diversified working day (rpart= + 0.259), and perception that family medicine offers a good salary (rpart= + 0.242).

CONCLUSION

To enable students during undergraduate studies to have practical experience with family medicine seems to be an important influence on judging family medicine attractive.

[Perceptions of the local government about the primary care physicians shortage - a survey among mayors in the Federal State of Baden-Wuerttemberg]

BACKGROUND

Local governments have a crucial role in dealing with the primary care physicians shortage (PS). The aim of this study is to evaluate the perspectives and experiences of the local mayors on this issue.

METHODS

In May 2011, all 1101 mayors in the Federal State of Baden-Wuerttemberg (BW) were invited to participate in the study by filling out a survey developed by the authors. Data were analysed descriptively.

RESULTS

Of the contacted mayors in BW, 63% (n=698) responded. More than 90% of the participants consider it their duty to ensure future primary care. 16% experienced local practice closures due to PS. The infrastructure provided by the communities seems to be at a high level, whereas emergency practices exist in only 15% of the communities at present. Supportive actions to attract new GPs are evaluated as appropriate by almost half of the participants.

CONCLUSIONS

The PS topic is of high relevance for communities in BW. In order to gain future physicians for their region, the majority of the communities are maintaining a high level of infrastructure and are willing to offer more actions. The young generation physicians need to be informed about these existing conditions. Innovative ideas should be implemented in individual communities as pilot projects.

[Development, factor-analytical control and psychometric evaluation of a questionnaire on specialty choices among medical students]

AIM OF THE STUDY

A questionnaire was developed and validated which assesses factors influencing career choices of medical students and their perception of possibilities in general practice.

METHODS

The first questionnaire version, which was developed based on a systematic literature review, was checked for comprehensibility and redundancy using concurrent think aloud. The revised version was filled out by a pilot sample of medical students and the factor structure was assessed using principal component analysis (PCA). The final version was filled out in an online survey by medical students of all 5 Medical Faculties in the federal state of Baden-Wuerttemberg. The factor structure was validated with a confirmatory factor analysis (CFA). Reliability was assessed as internal consistency using Cronbach's α.

RESULTS

The questionnaire comprises 2 parts: ratings of (A) the individual importance and of (B) the possibilities in general practice on 5-point scales. The first version comprising 118 items was shortened to 63 items after conducting interviews using concurrent think aloud. A further 3 items giving no information were removed after piloting the questionnaire on 179 students. The 27 items of part A were structured in 7 factors (PCA): image, personal ambition, patient orientation, work-life balance, future perspectives, job-related ambition, and variety in job. This structure had a critical fit in the CFA applied to the final version filled out by 1 299 students. Internal consistency of the factors was satisfactory to very good (Cronbach's α=0.55-0.81).

CONCLUSION

The questionnaire showed good psychometric properties. Further, not assessed factors influence career choice resulting in unexplained variance in our dataset and the critical fit of the model.

[Aspirations of medical students: "planning for a secure career" - results of an online-survey among students at five medical schools in Germany]

BACKGROUND

In times of shortage of doctors, expectations and interests of the future generation of doctors towards their career aspiration is of major importance. The aim of this study was to analyze expectations of medical students at the five medical schools in the State of Baden-Wuerttemberg (Germany) concerning their career choice and factors influencing it.

METHODS

Between January and February 2010, 1299 medical students (out of 12 062 medical students at the five medical schools) participated in an online-survey. In addition to sociodemographic items, career choice and aspects of planning reliability were raised.

RESULTS

Three quarters of the students assign a medical profession for their future occupation. There is a dominance of internal medicine (n = 152), gynaecology (n = 127), paediatrics (n = 125), surgery (n = 115), anaesthesiology (n = 101), and family medicine (n = 88). The time point of decision varies between the different undergraduate years of medical school and specialty. Students at the beginning of their studies seem to be interested mostly in surgery. During medical school the interests towards internal medicine grows. Regarding planning dependability important aspects for medical students were to work in a job that has a future (61.2 % fully agree), to have a safe job (57.7 %), and to have a safe income (57.1 %). Less important seems to be to have good opportunity to earn money (29.6 %).

CONCLUSIONS

Interest in a certain specialty changes markedly at during medical school. Factors such as economical guarantee, good future prospects and also the studies itself have an essential impact for students on choosing a specific career. Strategies to face physicians' shortage in different specialties need to be close to the needs and expectations of future physicians. This is not only valid for the undergraduate time period but also for the work circumstances of their future.

Zur Entwicklung transnationaler Unternehmensidentitäten in einer Weltgesellschaft

Vor dem Hintergrund der voranschreitenden Integration der Märkte zu einem weltumfassenden Wirtschaftssystem sowie der zunehmenden Transnationalisierung sozio-kultureller Beziehungen beschäftigen sich Sozial- und Wirtschaftswissenschafter, die die Folgen dieser Globalisierungstrends abzuschätzen versuchen, schon seit Beginn der 90er Jahre mit der Frage, ob territorial definierte, nationalstaatliche Kulturen in der Gegenwart noch das dominante Orientierungsmuster und die vorrangige Grundlage individueller Identifikation bilden. Auf der Grundlage neuer Hypothesen und Theorien werfen Sozial-, Wirtschafts- und Politikwissenschaftler sowie Anthropologen die Frage auf, ob im Zuge der globalen Integration Identifikationsgrundlagen entstehen, die zur Herausbildung transnationaler kultureller Identitäten führen. Diese Frage stellt sich insbesondere für die Personal- und Organisationsentwicklung in global agierenden Unternehmen mit Personen(-gruppen), die einen erheblichen Anteil ihres Arbeits- und Privatlebens an einer Vielzahl von Orten in unterschiedlichen Ländern verbringen.

Numerous anthropologists, political scientists, experts in organization theory and managers of organizational development departments agree in their assessment that national culture influences or even defines to a great extent the business culture within a country and therefore that organizations operating across borders encounter barriers with respect to transnational communication and cooperation. Many empirical studies which have been conducted corroborate this assumption, but few explicitly discuss the fundamental premises on which this perception is based, or how cross-national communication barriers can be explained. Based on a concept of culture that differs considerably from traditional models, a second group of social scientists has recently begun to question the inevitable persistence of such cross-national barriers to transnational interaction. Agreement with one or the other of the two views results in different implications for organizational development programs of cross-nationally operating companies.

Radiological findings in individuals at high risk of psychosis

OBJECTIVE

To assess the prevalence of radiological magnetic resonance imaging (MRI) findings in individuals at high risk of schizophrenia.

METHODS

MRI scans from individuals at high risk of schizophrenia (HR; n = 37) were assessed by a radiologist blind to group status and compared with scans from patients with first episode psychosis (FE; n = 30), depressive controls (DC; n = 17), and healthy controls (HC; n = 26).

RESULTS

There was a significantly higher proportion of radiological findings in individuals at high risk of schizophrenia (35%) and patients with first-episode psychosis (40%) than in patients with depression (18%) or healthy controls (12%). These differences were specific to findings regarded as potentially clinically significant as opposed to normal variants; however, there was no indication for medical treatment.

CONCLUSIONS

The results suggest that a large proportion of those at high risk of psychosis have radiological findings on MRI scanning, and that the prevalence of radiological findings in this group is similar to that in patients with first episode psychosis.

Estimation of x ray overexposure in a childhood leukaemia cluster by means of chromosome aberration analysis

Only multiple X ray diagnostics could be identified as a common risk factor in a leukaemia cluster that appeared between 1985-1989 in the municipality of Sittensen in northern Germany. In order to judge if the effect could be explained by irradiation dose, estimates were done in two of the leukaemia cases and seven former patients of a practice where some of the leukaemia cases had been treated for orthopaedic reasons. The methods used for the reconstruction of doses were physical simulation and biological dosimetry by dicentric chromosomes in peripheral lymphocytes. Compared to the Bremen laboratory control the mean frequency of dicentric chromosomes in the lymphocytes of the seven volunteers was significantly elevated. An overexposure of about 12-fold could be derived compared to state of the art X raying. At least two cases of the leukaemia cluster in Sittensen can therefore be correlated to an overexposure by diagnostic X rays.

Task-specific association of photoreceptor systems and steering parameters in Drosophila

Visual motion processing enables moving fruit flies to stabilize their course and altitude and to approach selected objects. Earlier attempts to identify task-specific pathways between two photoreceptor systems (peripheral retinula cells 1-6, and central retinula cells 7 + 8) and three steering parameters (wingstroke asymmetry, abdomen deflection, hindleg deflection) attributed course control and object fixation to peripheral retinula cells 1-6-mediated simultaneous reactions of these parameters. The present investigation includes first results from fixed flying or freely walking ninaE17 mutants which cannot synthesize the peripheral retinula cells 1-6 photoreceptor-specific opsin. Retention of about 12% of the normal course control and about 58% of the object fixation in these flies suggests partial input sharing for both responses and, possibly, a specialization for large-field (peripheral retinula cells 1-6) and small-field (central retinula cells 7 + 8) motion. Such signals must be combined to perceive relative motion between an object and its background. The combining links found in larger species might explain a previously neglected interdependence of course control and object fixation in Drosophila. -Output decomposition revealed an unexpected orchestration of steering. Wingstroke asymmetry and abdomen deflection do not contribute in fixed proportions to the yaw torque of the flight system. Different steering modes seem to be selected according to their actual efficiency under closed-loop conditions and to the degree of intended turning. An easy experimental access to abdominal steering is introduced.

Role of potassium channels in the control of renin secretion from isolated perfused rat kidneys

This study aimed to assess the relevance of specific potassium channels, such as inwardly or outwardly rectifying and calcium-regulated potassium channels, to the control of renin secretion. For this purpose we examined the effects of the K+ channel blockers 4-aminopyridine (1 mmol/l), barium (100 micromol/l), tetraethylammonium (2 mmol/l) and apamin (200 nmol/l) on basal renin secretion, on renin secretion stimulated by isoproterenol (10 nmol/l) and on the inhibition of renin secretion by angiotensin II (100-300 pmol/l) in the isolated rat kidney perfused at constant pressure. Whilst all four K+ channel blockers increased renal vascular resistance, only 4-aminopyridine and barium attenuated isoproterenol-stimulated renin secretion in an additive fashion and augmented the inhibitory effect of angiotensin II. These effects of K+ channel blockers were not changed by the L-type calcium channel blocker amlodipine (5 pmol/l), indicating that their effects on renin secretion are not due to voltage-operated calcium influx. Our data, moreover, suggest that potassium efflux from renal juxtaglomerular cells is not important for the inhibitory action of angiotensin II on renin secretion. As a consequence it appears that the membrane potential of renal juxtaglomerular cells per se is relevant to renin secretion such that membrane depolarization inhibits the exocytosis of renin whilst hyperpolarization favors renin secretion. By their activity, potassium channels can contribute to membrane hyperpolarization and thus facilitate renin secretion.

Betriebliche Weiterbildung zur Persönlichkeitsentwicklung für Führungskräfte

Betriebliche Bildung hat nicht nur die Zielsetzung, Mitarbeiter zu qualifizieren, sie will sie auch sensibilisieren. Verbreitete Werthaltungen, die der allgemeinen Bildung den Vorzug vor der beruflichen geben und umgekehrt sind nicht mehr zeitgemäß und führen zu Dualismen, die der Vorstellung von der Unvereinbarkeit von allgemeiner und betrieblicher Bildung neuen Nährboden geben. Diese Haltungen sind umso überraschender, da doch mit der ganzheitlichen Betrachtung des Menschen (und seiner Systeme) er immer in seiner beruflichen und privaten Rolle gesehen werden muß. Diese Betrachtung betrifft die Führungskräfte im Betrieb in besonderen Maße, da sie sich und andere in einem organisatorischen Rahmen und unter funktionellen Gesichtspunkten führen müssen. In dem Artikel soll geschildert werden, mit welchen Konzeptionen in der Führungskräfteförderung an Problemen gearbeitet wird, die sich auf den ganzen Menschen beziehen: Werte, Grundhaltungen, Einstellungen, Normen und Sinnfragen. Fragen, die im Seminar zentral sind lauten z.B. “Wo komme ich her?”, Wo stehe ich gerade?”, “Wo will ich hin?”.

Ziel des Beitrages ist es zu zeigen, daß es auch die Aufgabe von Personalforschung ist, die Umsetzungsmöglichkeiten von theoretischen Konzepten aufzuzeigen und zu entwickeln.

Which factor mediates reno-renal control of renin gene expression?

OBJECTIVE

To obtain information about possible pathways mediating the suppression of renin gene expression in the contralateral kidneys of stenosed kidneys.

DESIGN

The effects of unilateral renal denervation and of treatment with an angiotensin II antagonist (losartan) on renal renin gene expression were examined in a two-kidney, one-clip model.

METHODS

Renal renin messenger RNA levels, plasma renin activity, blood pressure and kidney weights were monitored over 10 days in adult male Sprague-Dawley rats with various unilateral reductions of renal blood flow achieved with silver clips of 0.2, 0.3 and 0.4 mm inner diameter.

RESULTS

With all the clip sizes used, renin messenger RNA levels increased transiently in the clipped kidneys, the time course and the magnitude of the increase being dependent on the degree of flow reduction. In the contralateral kidneys clipping caused sustained decreases in renin messenger RNA to levels proportional to the clip size. The suppression of renin gene expression in the contralateral kidneys was not related to compensatory growth of the organs nor to changes in plasma renin activity or arterial pressure. Unilateral denervation of the kidney before clipping had no influence on the characteristic increase and decrease in renin messenger RNA in the stenosed and contralateral kidneys, respectively. Treatment of the rats with losartan led to fourfold increases in renal renin messenger RNA levels and to sixfold increases in plasma renin activity in control rats. A 0.3-mm clip did not further increase renin messenger RNA or plasma renin activity in losartan-treated rats but again led to suppression of renin messenger RNA in the contralateral kidney to 50% of the levels found in the clipped kidneys.

CONCLUSIONS

The results suggest that the suppression of renin gene expression in the contralateral kidneys of stenosed kidneys is not due to compensatory renal growth nor mediated by systemic blood pressure, angiotensin II AT1 receptors or renal nerves. We therefore hypothesize that kidneys with reduced perfusion release a humoral factor that acts as a potent inhibitor of renin gene expression.

Direct correlation of parvalbumin levels with myosin isoforms and succinate dehydrogenase activity on frozen sections of rodent muscle

Parvalbumin (PV) is a soluble Ca++ binding protein which is particularly concentrated in fast muscles of rodents. We have developed a new protocol to fix frozen sections of muscle by formaldehyde vapor, which enabled us to immunochemically stain serial frozen sections for PV. Fiber types were defined on the basis of myosin ATPase stability, and of isomyosins identified by a variety of antibodies because ATPase stability alone yielded ambiguous results in the mouse. Slow Type I fibers in mouse and rat were devoid of PV and had intermediate to high SDH levels. Fast fiber subtypes IIA, IIB, and IIX-like were defined in the mouse on the basis of the similarity of their myosin heavy chain immunoreactivity to these types in the rat. The soleus muscle was usually PV negative, but a small population of strongly PV-positive IIX-like fibers was present in the mouse. In mouse fast muscle, small diameter IIA fibers were PV negative with high SDH activity. In both mouse and rat, PV reactivities of IIB and IIX fibers were higher than those of IIA and I, whereas SDH levels of IIA, IIX, and I fibers were higher than those of IIB. Thus, PV content correlated with the type of myosin ATPase but not with SDH levels. The method described for immunocytochemistry of PV may be applicable to other highly soluble proteins.

Color preferences, extraversion, and neuroticism of art students

Color preferences of 190 art students (Götz & Götz, 1974, 1975) were compared with the corresponding scores on extraversion (E) and neuroticism (N). It was found that the preferences of a group of 27 highly gifted young artists were different from preferences of average and less gifted Ss who had little or no artistic practice. In the latter group extraverts and ambiverts mainly preferred primary and secondary colors (light clear and dark clear tones included), while introverts preferred tertiary colors (earth colors) and achromatics. However, in the group of highly gifted Ss no significant differences between positive and negative rankings in both color categories were found. Neuroticism had no effect on color preferences; this holds for introverts and extraverts and for each single color.

Color preferences of art students: surface colors: II

In a previous study (Götz & Götz, 1974b) the preferences of 14 surface colors were analyzed. While this set contained only one red, one blue, one yellow, etc., the color set of the present investigation was extended, and the preferences of 5 different reds, blues, yellow, etc. were analyzed. Between the five variations of red and yellow, respectively, the greatest affective differences were found, while the opposite was true for the 5 oranges, pinks, and grays. The most preferred colors are 2 reds, 2 blues, and 2 yellows; least preferred are a greenish yellow, a penetrating red-violet, and all 5 pinks. Significant sex differences were found for 8 colors.

Color attitudes of art students and university students. I. Imagined colors

The color attitudes of 182 art students and 156 university students were tested. S's task was first to imagine colors and then to rank them on a seven-point rating scale. The results show that for art students only blue and red are “pleasant,” while gray and pink are “unpleasant” colors. Black and white count as “neutral.” The distributions of all other colors listed by Ss are not statistically different from chance. In comparison, university students show the same preference for blue and red as “pleasant” colors, but they prefer a third color, orange. Not only gray and pink are regarded as “unpleasant,” but also black and violet. White and beige are “neutral” colors. The only sex differences found were for violet in the art students group and for orange in the university students group. The drawbacks of the applied procedure, asking Ss to imagine colors, are discussed.

Introversion-extraversion and neuroticism in gifted and ungifted art students

It is generally assumed that artists are mostly introverted. In order to find out if they are also neurotic 50 gifted and 50 ungifted art students were tested with the Maudsley Personality Inventory. The results showed a clear tendency toward introversion and neuroticism for the gifted group. The mean scores of the ungifted group, on the contrary, were in the vicinity of normality. Next, out of the gifted group 15 highly gifted Ss were selected. Their mean scores on introversion and neuroricism were markedly higher than those of the 35 less gifted Ss.