CaM-dependent modulation of human CaV1.3 whole-cell and single-channel currents by C-terminal CaMKII phosphorylation site S1475.

Phosphorylation enables rapid modulation of voltage-gated calcium channels (VGCC) in physiological and pathophysiological conditions. How phosphorylation modulates human CaV1.3 VGCC, however, is largely unexplored. We characterized modulation of CaV1.3 gating via S1475, the human equivalent of a phosphorylation site identified in the rat. S1475 is highly conserved in CaV1.3 but absent from all other high-voltage activating calcium channel types co-expressed with CaV1.3 in similar tissues. Further, it is located in the C-terminal EF-hand motif, which binds calmodulin (CaM). This is involved in calcium-dependent channel inactivation (CDI). We used amino acid exchanges that mimic either sustained phosphorylation (S1475D) or phosphorylation resistance (S1475A). Whole-cell and single-channel recordings of phosphorylation state imitating CaV1.3 variants in transiently transfected HEK-293 cells revealed functional relevance of S1475 in human CaV1.3. We obtained three main findings: (1) CaV1.3_S1475D, imitating sustained phosphorylation, displayed decreased current density, reduced CDI and (in-) activation kinetics shifted to more depolarized voltages compared with both wildtype CaV1.3 and the phosphorylation-resistant CaV1.3_S1475A variant. Corresponding to the decreased current density, we find a reduced open probability of CaV1.3_S1475D at the single-channel level. (2) Using CaM overexpression or depletion, we find that CaM is necessary for modulating CaV1.3 through S1475. (3) CaMKII activation led to CaV1.3_WT-current properties similar to those of CaV1.3_S1475D, but did not affect CaV1.3_S1475A, confirming that CaMKII modulates human CaV1.3 via S1475. Given the physiological and pathophysiological importance of CaV1.3, our findings on the S1475-mediated interplay of phosphorylation, CaM interaction and CDI provide hints for approaches on specific CaV1.3 modulation under physiological and pathophysiological conditions. KEY POINTS: Phosphorylation modulates activity of voltage-gated L-type calcium channels for specific cellular needs but is largely unexplored for human CaV1.3 channels. Here we report that S1475, a CaMKII phosphorylation site identified in rats, is functionally relevant in human CaV1.3. Imitating phosphorylation states at S1475 alters current density and inactivation in a calmodulin-dependent manner. In wildtype CaV1.3 but not in the phosphorylation-resistant variant S1475A, CaMKII activation elicits effects similar to constitutively mimicking phosphorylation at S1475. Our findings provide novel insights on the interplay of modulatory mechanisms of human CaV1.3 channels, and present a possible target for CaV1.3-specific gating modulation in physiological and pathophysiological conditions.

Autism-associated mutations in the CaVß2 calcium-channel subunit increase Ba2+-currents and lead to differential modulation by the RGK-protein Gem.

Voltage-gated calcium-channels (VGCCs) are heteromers consisting of several subunits. Mutations in the genes coding for VGCC subunits have been reported to be associated with autism spectrum disorder (ASD). In a previous study, we identified electrophysiologically relevant missense mutations of CaVß2 subunits of VGCCs. From this, we derived the hypothesis that several CaVß2-mutations associated with ASD show common features sensitizing LTCCs and/or enhancing currents. Using a CaVß2d backbone, we performed extensive whole-cell and single-channel patch-clamp analyses of Ba2+ currents carried by Cav1.2 pore subunits co-transfected with the previously described CaVß2 mutations (G167S, S197F) as well as a recently identified point mutation (V2D). Furthermore, the interaction of the mutated CaVß2d subunits with the RGK protein Gem was analyzed by co-immunoprecipitation assays and electrophysiological studies. Patch-clamp analyses revealed that all mutations increase Ba2+ currents, e.g. by decreasing inactivation or increasing fraction of active sweeps. All CaVß2 mutations interact with Gem, but differ in the extent and characteristics of modulation by this RGK protein (e.g. decrease of fraction of active sweeps: CaVß2d_G167S > CaVß2d_V2D > CaVß2d_S197F). In conclusion, patch-clamp recordings of ASD-associated CaVß2d mutations revealed differential modulation of Ba2+ currents carried by CaV1.2 suggesting kind of an "electrophysiological fingerprint" each. The increase in current finally observed with all CaVß2d mutations analyzed might contribute to the complex pathophysiology of ASD and by this indicate a possible underlying molecular mechanism.

Inhibition of EIF-5A prevents apoptosis in human cardiomyocytes after malaria infection.

In this study, a determination of Troponin I and creatine kinase activity in whole-blood samples in a cohort of 100 small infants in the age of 2-5 years from Uganda with complicated Plasmodium falciparum malaria suggests the prevalence of cardiac symptoms in comparison to non-infected, healthy patients. Troponin I and creatine kinase activity increased during infection. Different reports showed that complicated malaria coincides with hypoxia in children. The obtained clinical data prompted us to further elucidate the underlying regulatory mechanisms of cardiac involvement in human cardiac ventricular myocytes. Complicated malaria is the most common clinical presentation and might induce cardiac impairment by hypoxia. Eukaryotic initiation factor 5A (eIF-5A) is involved in hypoxia induced factor (HIF-1α) expression. EIF-5A is a protein posttranslationally modified by hypusination involving catalysis of the two enzymes deoxyhypusine synthase (DHS) and deoxyhypusine hydroxylase. Treatment of human cardiomyocytes with GC7, an inhibitor of DHS, catalyzing the first step in hypusine biosynthesis led to a decrease in proinflammatory and proapoptotic myocardial caspase-1 activity in comparison to untreated cardiomyocytes. This effect was even more pronounced after co-administration of GC7 and GPI from P. falciparum simulating the pathology of severe malaria. Moreover, in comparison to untreated and GC7-treated cardiomyocytes, co-administration of GC7 and GPI significantly decreased the release of cytochrome C and lactate from damaged mitochondria. In sum, coadministration of GC7 prevented cardiac damage driven by hypoxia in vitro. Our approach demonstrates the potential of the pharmacological inhibitor GC7 to ameliorate apoptosis in cardiomyocytes in an in vitro model simulating severe malaria. This regulatory mechanism is based on blocking EIF-5A hypusination.

Single-Channel Resolution of the Interaction between C-Terminal CaV1.3 Isoforms and Calmodulin.

Voltage-dependent calcium (CaV) 1.3 channels are involved in the control of cellular excitability and pacemaking in neuronal, cardiac, and sensory cells. Various proteins interact with the alternatively spliced channel C-terminus regulating gating of CaV1.3 channels. Binding of a regulatory calcium-binding protein calmodulin (CaM) to the proximal C-terminus leads to the boosting of channel activity and promotes calcium-dependent inactivation (CDI). The C-terminal modulator domain (CTM) of CaV1.3 channels can interfere with the CaM binding, thereby inhibiting channel activity and CDI. Here, we compared single-channel gating behavior of two natural CaV1.3 splice isoforms: the long CaV1.342 with the full-length CTM and the short CaV1.342A with the C-terminus truncated before the CTM. We found that CaM regulation of CaV1.3 channels is dynamic on a minute timescale. We observed that at equilibrium, single CaV1.342 channels occasionally switched from low to high open probability, which perhaps reflects occasional binding of CaM despite the presence of CTM. Similarly, when the amount of the available CaM in the cell was reduced, the short CaV1.342A isoform showed patterns of the low channel activity. CDI also underwent periodic changes with corresponding kinetics in both isoforms. Our results suggest that the competition between CTM and CaM is influenced by calcium, allowing further fine-tuning of CaV1.3 channel activity for particular cellular needs.

Beta-adrenergic regulation of the heart expressing the Ser1700A/Thr1704A mutated Cav1.2 channel.

Beta-adrenergic stimulation of the heart increases ICa. PKA dependent phosphorylation of several amino acids (among them Ser 1700 and Thr 1704 in the carboxy-terminus of the Cav1.2 α1c subunit) has been implicated as decisive for the ß-adrenergic up-regulation of cardiac ICa. Mutation of Ser 1700 and Thr 1704 to alanine results in the Cav1.2PKA_P2-/- mice. Cav1.2PKA_P2-/- mice display reduced cardiac L-type current. Fractional shortening and ejection fraction in the intact animal and ICa in isolated cardiomyocytes (CM) are stimulated by isoproterenol. Cardiac specific expression of the mutated Cav1.2PKA_P2-/- gene reduces Cav1.2 α1c protein concentration, ICa, and the ß-adrenergic stimulation of L-type ICa in CMs. Single channels were not detected on the CM surface of the cCav1.2PKA_P2-/- hearts. This outcome supports the notion that S1700/1704 is essential for expression of the Cav1.2 channel and that isoproterenol stimulates ICa in Cav1.2PKA_P2-/- CMs.

Medical students' medication communication skills regarding drug prescription-a qualitative analysis of simulated physician-patient consultations.

PURPOSE: Poor medication communication of physicians to patients is detrimental, e.g. for medication adherence. Reasons for physicians' deficits in medication communication may be unfavourable conditions in daily practice or already insufficient training during their (undergraduate) medical studies. We explored medical students' communication on new medications in simulated physician-patient conversations to identify actual deficits indicating apparent educational needs. METHODS: Fifth year medical students attending a mandatory course at the University of Cologne had simulated physician-patient consultations aiming at drug prescription. In 2015, 21 consultations were recorded, transcribed and subjected to qualitative content analysis based on the method of inductive coding. RESULTS: Even essential information on drug therapy was often lacking (e.g. adverse effects, drug administration). Some aspects were addressed more frequently than others. This seemed to differ depending on the diagnosis underlying the particular treatment (acute event vs. chronic disease). The extent of information on drug treatments given in simulated physician-patient consultations varied significantly between students. CONCLUSIONS: Fifth year medical students showed appreciable deficits in communicating drug prescriptions to patients though there were remarkable inter-individual differences. Our findings suggest that communication on drug therapy to patients is no self-evolving skill. Thus, there is obviously a need for emphasizing medication communication in the training of medical students. Communication aids specifically aiming at medication communication might facilitate learning of adequate medication communication skills.

Spectrum of Cav1.4 dysfunction in congenital stationary night blindness type 2.

Defective retinal synaptic transmission in patients affected with congenital stationary night blindness type 2 (CSNB2) can result from different dysfunction phenotypes in Cav1.4 L-type calcium channels. Here we investigated two prototypical Cav1.4 variants from either end of the functional spectrum. Using whole-cell and single-channel patch-clamp techniques, we provide analysis of the biophysical characteristics of the point mutation L860P and the C-terminal truncating mutation R1827X. L860P showed a typical loss-of-function phenotype attributed to a reduced number of functional channels expressed at the plasma membrane as implied by gating current and non-stationary noise analyses. This phenotype can be rationalized, because the inserted proline is predicted to break an amphipatic helix close to the transmembrane segment IIIS1 and thus to reduce channel stability and promote misfolding. In fact, L860P was subject to an increased turnover. In contrast, R1827X displayed an apparent gain-of-function phenotype, i.e., due to a hyperpolarizing shift of the IV-curve and increased single-channel activity. However, truncation also resulted in the loss of functional C-terminal modulation and thus unmasked calcium-dependent inactivation. Thus R1827X failed to support continuous calcium influx. Current inactivation curtails the dynamic range of photoreceptors (e.g., when adapting to variation in illumination). Taken together, the analysis of two representative mutations that occur in CSNB2 patients revealed fundamental differences in the underlying defect. These may explain subtle variations in the clinical manifestation and must be taken into account, if channel function is to be restored by pharmacochaperones or related approaches.

Lucky guess or knowledge: a cross-sectional study using the Bland and Altman analysis to compare confidence-based testing of pharmacological knowledge in 3rd and 5th year medical students.

Multiple-choice-questions are common in medical examinations, but guessing biases assessment results. Confidence-based-testing (CBT) integrates indicated confidence levels. It has been suggested that correctness of and confidence in an answer together indicate knowledge levels thus determining the quality of a resulting decision. We used a CBT approach to investigate whether decision quality improves during undergraduate medical education. 3rd- and 5th-year students attended formative multiple-choice exams on pharmacological issues. Students were asked to indicate their confidence in a given answer. Correctness of answers was scored binary (1-correct; 0-wrong) and confidence levels were transformed to an ordinal scale (guess: 0; rather unsure: 0.33; rather sure: 0.66; very sure: 1). 5th-year students gave more correct answers (73 ± 16 vs. 49 ± 13 %, p < 0.05) and were on average more confident regarding the correctness of their answers (0.61 ± 0.18 vs. 0.46 ± 0.13, p < 0.05). Correlation of these parameters was stronger for 5th-year students (r = 0.81 vs. r = 0.52), but agreement of confidence and correctness ('centration') was lower. By combining the Bland-and-Altman approach with categories of decision-quality we found that 5th-year students were more likely to be 'well-informed' (41 vs. 5 %), while more 3rd-students were 'uninformed' (24 vs. 76 %). Despite a good correlation of exam results and confidence in given answers increased knowledge might be accompanied by a more critical view at the own abilities. Combining the statistical Bland-and-Altman analysis with a theoretical approach to decision-quality, more advanced students are expected to apply correct beliefs, while their younger fellows are rather at risk to hesitate or to act amiss.

Protective effects of Gαi3 deficiency in a murine heart-failure model of ß1-adrenoceptor overexpression.

We have shown that in murine cardiomyopathy caused by overexpression of the ß1-adrenoceptor, Gαi2-deficiency is detrimental. Given the growing evidence for isoform-specific Gαi-functions, we now examined the consequences of Gαi3 deficiency in the same heart-failure model. Mice overexpressing cardiac ß1-adrenoceptors with (ß1-tg) or without Gαi3-expression (ß1-tg/Gαi3-/-) were compared to C57BL/6 wildtypes and global Gαi3-knockouts (Gαi3-/-). The life span of ß1-tg mice was significantly shortened but improved when Gαi3 was lacking (95% CI: 592-655 vs. 644-747 days). At 300 days of age, left-ventricular function and survival rate were similar in all groups. At 550 days of age, ß1-tg but not ß1-tg/Gαi3-/- mice displayed impaired ejection fraction (35 ± 18% vs. 52 ± 16%) compared to wildtype (59 ± 4%) and Gαi3-/- mice (60 ± 5%). Diastolic dysfunction of ß1-tg mice was prevented by Gαi3 deficiency, too. The increase of ANP mRNA levels and ventricular fibrosis observed in ß1-tg hearts was significantly attenuated in ß1-tg/Gαi3-/- mice. Transcript levels of phospholamban, ryanodine receptor 2, and cardiac troponin I were similar in all groups. However, Western blots and phospho-proteomic analyses showed that in ß1-tg, but not ß1-tg/Gαi3-/- ventricles, phospholamban protein was reduced while its phosphorylation increased. Here, we show that in mice overexpressing the cardiac ß1-adrenoceptor, Gαi3 deficiency slows or even prevents cardiomyopathy and increases shortened life span. Previously, we found Gαi2 deficiency to aggravate cardiac dysfunction and mortality in the same heart-failure model. Our findings indicate isoform-specific interventions into Gi-dependent signaling to be promising cardio-protective strategies.

Pharmacoresistant Cav 2·3 (E-type/R-type) voltage-gated calcium channels influence heart rate dynamics and may contribute to cardiac impulse conduction.

Voltage-gated Ca(2+) channels regulate cardiac automaticity, rhythmicity and excitation-contraction coupling. Whereas L-type (Cav 1·2, Cav 1·3) and T-type (Cav 3·1, Cav 3·2) channels are widely accepted for their functional relevance in the heart, the role of Cav 2·3 Ca(2+) channels expressing R-type currents remains to be elucidated. We have investigated heart rate dynamics in control and Cav 2·3-deficient mice using implantable electrocardiogram radiotelemetry and pharmacological injection experiments. Autonomic block revealed that the intrinsic heart rate does not differ between both genotypes. Systemic administration of isoproterenol resulted in a significant reduction in interbeat interval in both genotypes. It remained unaffected after administering propranolol in Cav 2·3(-|-) mice. Heart rate from isolated hearts as well as atrioventricular conduction for both genotypes differed significantly. Additionally, we identified and analysed the developmental expression of two splice variants, i.e. Cav 2·3c and Cav 2·3e. Using patch clamp technology, R-type currents could be detected in isolated prenatal cardiomyocytes and be related to R-type Ca(2+) channels. Our results indicate that on the systemic level, the pharmacologically inducible heart rate range and heart rate reserve are impaired in Cav 2·3 (-|-) mice. In addition, experiments on Langendorff perfused hearts elucidate differences in basic properties between both genotypes. Thus, Cav 2·3 does not only contribute to the cardiac autonomous nervous system but also to intrinsic rhythm propagation.

A simple approach of applying blended learning to problem-based learning is feasible, accepted and does not affect evaluation and exam results-a just pre-pandemic randomised controlled mixed-method study.

We tested for feasibility, acceptance, and "non-inferiority" of small-group teaching applying blended learning (i.e., the integration of face-to-face and online instruction) to problem-based learning (bPbL) compared to conventional PbL (cPbL). In a just pre-pandemic, randomised controlled trial, 317 students attended either bPbL or cPbL groups. The first meeting of the bPbL groups took place online via written internet chat, while cPbL groups met on site. All groups met on site the second time. All students had the opportunity to attend lectures either on site or as videos on demand. We analysed student evaluation data, results in a final summative exam, attendance of lectures on site and use of lecture videos. Furthermore, we performed a qualitative analysis of student statements made in semi-structured group interviews about pros and cons of the bPbL approach. There was no difference between students of either bPbL or cPbL groups with respect to exam results (score: 14.3 ± 2.8 vs. 13.8 ± 2.7) or course evaluation. However, relatively more bPbL than cPbL students reported having used lecture videos, while the proportion of those attending lectures on-site was higher among cPbL students. Interviews revealed that some of the bPbL students' experiences were unexpected and feared disadvantages seemed to be less severe than expected. Participation in a blended PbL format did not worsen course evaluations or exam results, but seemed to influence lecture attendance. The combination of face-to-face and digital elements could be suitable as a hybrid approach to digital instruction in the post-pandemic era.

Implementing nutritional medicine into medical curricula: A student-initiated course improves knowledge and attitudes.

BACKGROUND & AIMS: Although the risks and opportunities of nutrition in health trajectories are well known, it is rarely addressed in doctors' daily routine. This is partly related to physicians' lack of confidence in their ability to provide nutritional counselling, possibly due to insufficient training in medical school. Our study aimed at assessing the status quo of nutrition in the German medical curricula and the impact of a recently implemented, student-initiated online teaching initiative on perceived competence, knowledge and attitudes. METHODS: "Eat This!" was the first Germany-wide initiative for online nutritional medicine (NM) education, consisting of 11 digital lectures on nutrition basics, nutrition medicine and public health nutrition. The contact time with NM during studies as well as the effects on students' attitudes towards NM, their self-perceived competence in NM and their nutrition knowledge were assessed from October 2020 to February 2021 in a cross-sectional as well as a prospective study using online questionnaires. RESULTS: Over 1500 medical students from 42 German faculties participated in the lecture series and the online survey. One hundred and twenty-two students formed a control group. Although considering the topic relevant, students rated their training in NM as insufficient, in terms of both quality and quantity. Initially, they did not feel able to counsel patients and rated their knowledge as low. However, self-ratings and the score in a 33-item multiple-choice test knowledge improved by participating in Eat This! as did their attitude towards nutrition and planetary health. No such changes were observed in the control group of 122 students not attending the course. CONCLUSION: Our results show that education in NM at German medical schools is perceived insufficient despite high student interest. But even low-threshold educational options like "Eat This!" can improve students' perceived competence, knowledge, and attitudes, and thus be an efficient and cost-effective way to address related deficits.

A comparison of urinary bladder weight in male and female mice across five models of diabetes and obesity.

Introduction: Diabetes often leads to lower urinary tract dysfunction. The most frequently assessed parameter of urinary bladder dysfunction in animal models of diabetes is an enlargement of the bladder, which is consistently observed in type 1 and less consistently in type 2 diabetes. The vast majority of studies on bladder weight in animal models of diabetes and obesity has been performed in males, and no studies have directly compared this outcome parameter between sexes. Methods: Therefore, we have compared bladder weight and bladder/body weight ratio in five mouse models of obesity and diabetes (RIP-LCMV, db/db, ob/ob (two studies), insulin receptor substrate 2 (IRS2) knock-out mice and mice on a high-fat diet; pre-specified secondary analysis of a previously reported study). Results: In a pooled analysis of the control groups of all studies, females exhibited slightly lower glucose levels, lower body weight, and lower bladder weight, but bladder/body weight ratio was similar in both sexes (0.957 vs. 0.986 mg/g, mean difference 0.029 [-0.06; 0.118]). Among the six diabetic/obese groups, bladder/body weight ratio was similar in both sexes in three but smaller in female mice in three other groups. The mRNA expression of a panel of genes implied in the pathophysiology of bladder enlargement and/or fibrosis and inflammation did not differ systematically between sexes. Conclusions: We conclude that sex differences in diabetes/obesity-associated bladder enlargement may be model dependent.

Improvement of Dietary Habits among German Medical Students by Attending a Nationwide Online Lecture Series on Nutrition and Planetary Health ("Eat This!").

Nutrition is a major influential factor in optimizing human health and environmental sustainability. Medical students often do not follow national dietary guideline recommendations. Raising awareness of a healthy lifestyle is important as physicians with healthy lifestyle behaviors are more likely to counsel on nutrition. Our study aims to evaluate a Germany-wide online lecture series on nutritional medicine, "Eat This!". Before and after the course, 520 medical students who participated and 64 who did not participate in the course (comparison group) filled out an online survey. To assess the students' dietary habits, a validated FFQ was used. According to this questionnaire, only 31% of the lecture participants consumed enough fruits and 24% consumed enough vegetables, while almost half of the students exceeded the recommended maximum amount of crisps and sweets. After attending the lecture series, guideline adherence with respect to fruits and vegetables showed a significant increase, as did awareness of healthy nutrition and percentage of students with low-risk lifestyle habits. Our results show that low-threshold approaches, such as "Eat This!", can positively influence the dietary behaviors and lifestyle habits of medical students. This can help future doctors fulfill their role in the fight against the global burden of non-communicable diseases.

Inhibitory effects on L- and N-type calcium channels by a novel CaVß1 variant identified in a patient with autism spectrum disorder.

Voltage-gated calcium channel (VGCC) subunits have been genetically associated with autism spectrum disorders (ASD). The properties of the pore-forming VGCC subunit are modulated by auxiliary ß-subunits, which exist in four isoforms (CaVß1-4). Our previous findings suggested that activation of L-type VGCCs is a common feature of CaVß2 subunit mutations found in ASD patients. In the current study, we functionally characterized a novel CaVß1b variant (p.R296C) identified in an ASD patient. We used whole-cell and single-channel patch clamp to study the effect of CaVß1b_R296C on the function of L- and N-type VGCCs. Furthermore, we used co-immunoprecipitation followed by Western blot to evaluate the interaction of the CaVß1b-subunits with the RGK-protein Gem. Our data obtained at both, whole-cell and single-channel levels, show that compared to a wild-type CaVß1b, the CaVß1b_R296C variant inhibits L- and N-type VGCCs. Interaction with and modulation by the RGK-protein Gem seems to be intact. Our findings indicate functional effects of the CaVß1b_R296C variant differing from that attributed to CaVß2 variants found in ASD patients. Further studies have to detail the effects on different VGCC subtypes and on VGCC expression.

Analysis of 16 studies in nine rodent models does not support the hypothesis that diabetic polyuria is a main reason of urinary bladder enlargement.

The urinary bladder is markedly enlarged in the type 1 diabetes mellitus model of streptozotocin-injected rats, which may contribute to the frequent diabetic uropathy. Much less data exists for models of type 2 diabetes. Diabetic polyuria has been proposed as the pathophysiological mechanism behind bladder enlargement. Therefore, we explored such a relationship across nine distinct rodent models of diabetes including seven models of type 2 diabetes/obesity by collecting data on bladder weight and blood glucose from 16 studies with 2-8 arms each; some studies included arms with various diets and/or pharmacological treatments. Data were analysed for bladder enlargement and for correlations between bladder weight on the one and glucose levels on the other hand. Our data confirm major bladder enlargement in streptozotocin rats and minor if any enlargement in fructose-fed rats, db/db mice and mice on a high-fat diet; enlargement was present in some of five not reported previously models. Bladder weight was correlated with blood glucose as a proxy for diabetic polyuria within some but not other models, but correlations were moderate to weak except for RIP-LCMV mice (r 2 of pooled data from all studies 0.0621). Insulin levels also failed to correlate to a meaningful extent. Various diets and medications (elafibranor, empagliflozin, linagliptin, semaglutide) had heterogeneous effects on bladder weight that often did not match their effects on glucose levels. We conclude that the presence and extent of bladder enlargement vary markedly across diabetes models, particularly type 2 diabetes models; our data do not support the idea that bladder enlargement is primarily driven by glucose levels/glucosuria.

Aspects of Medication and Patient participation-an Easy guideLine (AMPEL). A conversation guide increases patients' and physicians' satisfaction with prescription talks.

Patients want more information and active participation in medical decisions. Information and active participation correlate with increased adherence. A conversation guide, combining patient-relevant drug information with steps of shared decision-making, was developed to support physicians in effective and efficient prescription talks. Six GP trainees in community-based primary care practices participated in a controlled pilot study in sequential pre-post design. Initially, they conducted 41 prescription talks as usual, i.e., without knowing the guide. Then, they conducted 23 talks considering the guide (post-intervention phase). Immediately after the respective talk, patients filled in a questionnaire on satisfaction with the information on medication and physician-patient interaction, and physicians about their satisfaction with the talk and the application of the guide. Patients felt better informed after guide-based prescription talks (e.g., SIMS-D in median 10 vs. 17, p < 0.05), more actively involved (KPF-A for patient activation 2.9 ± 0.8 vs. 3.6 ± 0.8, p < 0.05), and more satisfied with the physician-patient interaction. Physicians rated the guide helpful and feasible. Their satisfaction with the conversation was significantly enhanced during the post-intervention phase. The evaluation of the duration of the talk was not influenced. Enhanced patients' and physicians' satisfaction with prescription talks encourages further examinations of the conversation guide. We invite physicians to try our guide in everyday medical practice.

A simulation-based module in pharmacology education reveals and addresses medical students' deficits in leading prescription talks.

Although doctor-patient communication is essential for drug prescription, the literature reveals deficits in this area. An educational approach at the Cologne medical faculty aims at identifying and addressing those deficits in medical students.Fifth-year medical students first conducted a simulated prescription talk spontaneously. Subsequently, the conversation was discussed with peer students. A pharmacist moderated the discussion based upon a previously developed conversation guide. Afterwards, the same student had the conversation again, but as if for the first time. Conversations were video-recorded, transcribed and subjected to quantitative content analysis. Four days after the simulation, the students who conducted the talk, those who observed and discussed it, and students who did neither, completed a written test that focused on the content of an effective prescription talk.Content analysis revealed clear deficits in spontaneously led prescription talks. Even essential information as on adverse drug reactions were often lacking. Prescription talks became clearly more informative and comprehensive after the short, guided peer discussion. With regard to a comprehensive, informative prescription talk, the written test showed that both the students who conducted the talk and those who only observed it performed clearly better than the students who did not participate in the educational approach.Deficits regarding prescription talks are present in 5th year medical students. We provide an approach to both identify and address these deficits. It thus may be an example for training medical students in simulated and clinical environments like the EACPT recommended to improve pharmacology education.

Depolarization induces nociceptor sensitization by CaV1.2-mediated PKA-II activation.

Depolarization drives neuronal plasticity. However, whether depolarization drives sensitization of peripheral nociceptive neurons remains elusive. By high-content screening (HCS) microscopy, we revealed that depolarization of cultured sensory neurons rapidly activates protein kinase A type II (PKA-II) in nociceptors by calcium influx through CaV1.2 channels. This effect was modulated by calpains but insensitive to inhibitors of cAMP formation, including opioids. In turn, PKA-II phosphorylated Ser1928 in the distal C terminus of CaV1.2, thereby increasing channel gating, whereas dephosphorylation of Ser1928 involved the phosphatase calcineurin. Patch-clamp and behavioral experiments confirmed that depolarization leads to calcium- and PKA-dependent sensitization of calcium currents ex vivo and local peripheral hyperalgesia in the skin in vivo. Our data suggest a local activity-driven feed-forward mechanism that selectively translates strong depolarization into further activity and thereby facilitates hypersensitivity of nociceptor terminals by a mechanism inaccessible to opioids.

Inactivation of L-type calcium channels is determined by the length of the N terminus of mutant beta(1) subunits.

Voltage-dependent calcium channel (Ca(v)) pores are modulated by cytosolic beta subunits. Four beta-subunit genes and their splice variants offer a wide structural array for tissue- or disease-specific biophysical gating phenotypes. For instance, the length of the N terminus of beta(2) subunits has major effects on activation and inactivation rates. We tested whether a similar mechanism principally operates in a beta(1) subunit. Wild-type beta(1a) subunit (N terminus length 60 aa) and its newly generated N-terminal deletion mutants (51, 27 and 18 aa) were examined within recombinant L-type calcium channel complexes (Ca(v)1.2 and alpha(2)delta2) in HEK293 cells at the whole-cell and single-channel level. Whole-cell currents were enhanced by co-transfection of the full-length beta(1a) subunit and by all truncated constructs. Voltage dependence of steady-state activation and inactivation did not depend on N terminus length, but inactivation rate was diminished by N terminus truncation. This was confirmed at the single-channel level, using ensemble average currents. Additionally, gating properties were estimated by Markov modeling. In confirmation of the descriptive analysis, inactivation rate, but none of the other transition rates, was reduced by shortening of the beta(1a) subunit N terminus. Our study shows that the length-dependent mechanism of modulating inactivation kinetics of beta(2) calcium channel subunits can be confirmed and extended to the beta(1) calcium channel subunit.