Hypertrophic cardiomyopathy MYH7 mutation R723G alters mRNA secondary structure.

Point mutation R723G in the MYH7 gene causes hypertrophic cardiomyopathy (HCM). Heterozygous patients with this mutation exhibit a comparable allelic imbalance of the MYH7 gene. On average 67% of the total MYH7 mRNA are derived from the MYH7R723G-allele and 33% from the MYH7WT allele. Mechanisms underlying mRNA allelic imbalance are largely unknown. We suggest that a different mRNA lifetime of the alleles may cause the allelic drift in R723G patients. A potent regulator of mRNA lifetime is its secondary structure. To test for alterations in the MYH7R723G mRNA structure we used selective 2'-hydroxyl acylation analyzed by primer extension (SHAPE) analysis. We show significantly different SHAPE reactivity of wild-type and MYH7R723G RNA, which is in accordance with bioinformatically predicted structures. Thus, we provide the first experimental evidence for mRNA secondary structure alterations by the HCM point mutation. We assume that this may result in a prolonged lifetime of MYH7R723G mRNA in vivo and subsequently in the determined allelic imbalance.

Successful knock-in of Hypertrophic Cardiomyopathy-mutation R723G into the MYH7 gene mimics HCM pathology in pigs.

Familial Hypertrophic Cardiomyopathy (HCM) is the most common inherited cardiac disease. About 30% of the patients are heterozygous for mutations in the MYH7 gene encoding the ß-myosin heavy chain (MyHC). Hallmarks of HCM are cardiomyocyte disarray and hypertrophy of the left ventricle, the symptoms range from slight arrhythmias to sudden cardiac death or heart failure. To gain insight into the underlying mechanisms of the diseases' etiology we aimed to generate genome edited pigs with an HCM-mutation. We used TALEN-mediated genome editing and successfully introduced the HCM-point mutation R723G into the MYH7 gene of porcine fibroblasts and subsequently cloned pigs that were heterozygous for the HCM-mutation R723G. No off-target effects were determined in the R723G-pigs. Surprisingly, the animals died within 24 h post partem, probably due to heart failure as indicated by a shift in the a/ß-MyHC ratio in the left ventricle. Most interestingly, the neonatal pigs displayed features of HCM, including mild myocyte disarray, malformed nuclei, and MYH7-overexpression. The finding of HCM-specific pathology in neonatal R723G-piglets suggests a very early onset of the disease and highlights the importance of novel large animal models for studying causative mechanisms and long-term progression of human cardiac diseases.

Plasma concentration of high-mobility group box 1 (HMGB1) after 100 drop to vertical jumps and after a 1200-km bicycle race.

High-mobility group box 1 (HMGB1) has recently been reported to be involved in proinflammation and tissue repair. Therefore, we hypothesized that HMGB1 is released into the bloodstream after eccentric exercises or prolonged endurance activities. Blood samples from 11 participants that performed 100 drop to vertical jumps (DVJ) and from 10 participants that took part in the 1200-km 'Paris-Brest-Paris' bicycle race (PBP) were tested for HMGB1 and creatine kinase (CK) levels. CK increased after both DVJ (pre: 150.6 ± 81.5 U/L; post: 188.8 ± 95.5 U/L 8 h: 790.5 ± 346.4 U/L) and PBP (pre: 81.3 ± 36.4 U/L; post: 725.2 ± 229.5 U/L; 12 h: 535.8 ± 188.6 U/L), indicating membrane damage. However, HMGB1 plasma levels remained below the detection limit (78 pg/mL) of the applied enzyme-linked immunosorbent assay kit for all blood samples analysed. That is, neither high intensity eccentric exercises (DVJ) nor prolonged endurance events (PBP) seemed to affect HMGB1 levels in blood at selected time points.

Electrically induced muscle cramps induce hypertrophy of calf muscles in healthy adults.

OBJECTIVES: Skeletal muscles usually cramp at short lengths, where the tension that can be exerted by muscle fibers is low. Since high tension is an important anabolic stimulus, it is questionable if cramps can induce hypertrophy and strength gains. In the present study we investigated if electrically induced cramps (EIMCs) can elicit these adaptations. METHODS: 15 healthy male adults were randomly assigned to an intervention (IG; n=10) and a control group (CG; n=5). The cramp protocol (CP) applied twice a week to one leg of the IG, consisted of 3x6 EIMCs, of 5 s each. Calf muscles of the opposite leg were stimulated equally, but were hindered from cramping by fixating the ankle at 0° plantar flexion (nCP). RESULTS: After six weeks, the cross sectional area of the triceps surae was similarly increased in both the CP (+9.0±3.4%) and the nCP (+6.8±3.7%). By contrast, force of maximal voluntary contractions, measured at 0° and 30° plantar flexion, increased significantly only in nCP (0°: +8.5±8.8%; 30°: 11.7±13.7%). CONCLUSION: The present data indicate that muscle cramps can induce hypertrophy in calf muscles, though lacking high tension as an important anabolic stimulus.

The repeated bout effect: is the blunted creatine kinase response an effect of an altered enzyme inactivation kinetic?

AIM: If unaccustomed lengthening contractions are repeated within a certain period of time, muscle damage symptoms are blunted. This observation, often referred to as the repeated bout effect (RBE), also holds true for the response of muscle damage markers like creatine kinase (CK). However, measuring plasma enzyme activity rather than the concentration of enzyme protein might conceal the actual amount of damaged tissue. Therefore, the primary aim of the study was to investigate if the RBE of CK can partially be explained by enzyme inactivation. METHODS: Ten healthy male subjects performed two bouts of 100 drop-to-vertical jumps (DVJs) from a 70-cm high platform at an interval of three weeks. CK activity, CK concentration, and neutrophils were measured prior to, and on four consecutive days after the interventions. RESULTS: Besides significant main effects, there was a significant group by time interaction for the specific CK activity (CK activity in blood [U/L] divided by the enzyme concentration [ng/mL]). Higher values following the first bout (133.1±99.4 U/µg) than the second bout (94.7±63.0 U/µg) indicate that the ratio of inactive to active CK molecules increased. Neutrophil levels were similar following both bouts and differed only at 8 hours (7.0±2.5 bout 1, 5.1±1.6 bout 2). CONCLUSION: The findings of the present study support the hypothesis that the blunted response of CK activity after a repeated bout of eccentric exercise is not solely the result of tissue protection, but can be at least partially attributed to enzyme inactivation.

[Prevalence and Correlates of Substance Use in 5,688 Vocational School Students]. / Verbreitung und Korrelate des Substanzkonsums unter 5,688 Auszubildenden an beruflichen Schulen.

OBJECTIVE: The aim of this study was to investigate the prevalence of substance use of German apprentices in vocational schools, considering socio-demographic characteristics and vocational field. METHODS: Cross-sectional study of 5,688 first year apprentices. These were 5,001 apprentices from 34 schools of the "Dual System" and 687 students from 15 vocational schools of the social and health sector. Sociodemographic characteristics and prevalence of tobacco, alcohol, cannabis, other illegal drugs, and pharmaceuticals were assessed. There was also a screening for problematic alcohol and cannabis use. The paper-pencil survey was conducted by trained research staff in 7 German federal states from September to December 2012. RESULTS: Half of the apprentices (49.9%) used tobacco in the 30 days prior to questioning, 40.7% reported daily smoking. Alcohol use in the past 30 days was reported by 68.9%, 45.0% of the sample had a positive screening result for problematic alcohol use. Prevalence rates for the use of cannabis and other illegal drugs in the last 30 days were 7.5% and 2.6%, taking pharmaceuticals was reported by 20.7%. Significant correlates of substance use were gender and socio-economic status. Differences between vocational clusters were also found, with higher average rates in service-based and commercial-technical professions. However, these differences could mostly be explained by sociodemographic differences in the composition of the vocational clusters. CONCLUSIONS: Use of psychotropic substances is a widespread activity in German apprentices. Prevalence rates are higher than in the same age total population. The highest proportion of variance was explained by differences in gender and socio-economic status.

A radical change in traffic law: effects on fatalities in the Czech Republic.

BACKGROUND: This study examines short- and long-run effects of a new-stricter-road traffic law on traffic accident-related fatalities in the Czech Republic. The law introduced tougher punishments through the introduction of a demerit point system and a manifold increase in fines, together with augmented authority of traffic police. METHODS: Identification is based on difference-in-differences methodology, with neighbouring countries serving as a control group. RESULTS: There was a sharp, 33.3%, decrease in accident-related fatalities during the first three post-reform months. This translates into 127 saved lives (95% confidence interval: 51, 204). The decline was, however, temporary; the estimates of the effects going beyond the first year are around zero. Unique data on traffic police activity reveal that police resources devoted to traffic law enforcement gradually declined. CONCLUSIONS: Tougher penalties have significant, but often short-lived effects. Weaker enforcement in the aftermath of such reforms may explain the absence of long-run effects.

Dissociated representations of irritation and valence in human primary olfactory cortex.

Irritation and negative valence are closely associated in perception. However, these perceptual aspects can be dissociated in olfaction where irritation can accompany both pleasant and unpleasant odorants. Whereas the sensation of odor reflects transduction at olfactory receptors, irritation reflects concurrent transduction of the odorant at trigeminal receptors. Thus a stimulus can be either a pure olfactant activating the olfactory receptors only or a bimodal odorant activating both types of receptors. Using event-related functional magnetic resonance imaging and a 2 x 2 experimental design contrasting odorant valence (pleasant/unpleasant) and odorant type (pure olfactant/bimodal) we found activity in piriform cortex to be associated with valence, and not type, of odors. In contrast, activity in the olfactory tubercle was associated with type, and not valence, of odors. Importantly, this was found when perceived intensity was held equal across odorants. These findings suggest that dissociable neural substrates subserve the encoding of irritation and valence in olfaction.

Prior psychiatric problems in rehabilitation clients with work-related injuries.

Psychiatric histories were obtained in 56 patients beginning rehabilitation following a work-related injury in order to establish the temporal relationship between the onset of psychiatric problems and the date of the work injury. The presence of major depression and alcohol abuse was determined using structured, directed interviews and the criteria set forth in the Diagnostic and Statistical Manual of Mental Disorders. A history of either alcohol abuse or depression was found in 36 (64.3%) of the 56 subjects. Of these 36 subjects, 32 (88.9%) reported a history of psychiatric problems that antedated the work injury. These data suggest that, in injured workers, the conceptualization of psychiatric problems solely as reactive illnesses in otherwise psychiatrically healthy persons is often inaccurate. Furthermore, these data suggest the hypothesis that the presence of clinical depression or alcohol abuse may increase the risks of a work-related injury.

Prediction of return to work by rehabilitation professionals.

Rehabilitation therapists made predictions of return to work for 57 patients evaluated prior to beginning a work-hardening program. These predictions, along with 14 specific demographic, injury, and physical function measures were entered into a stepwise discriminant analysis to develop a predictive model for return to work. Therapists correctly predicted the eventual return to work for 47 (73.7%) of the 57 subjects. Therapist prediction was the most powerful variable in the model, explaining 29% of the variance (p≤.0001). Only two other variables, self-report of pain severity and injury type, contributed significantly to the prediction model, accounting respectively for 12% and 9% of the variance (p's<.05). These data highlight the predictive acuity of rehabilitation therapists and suggest that the process involved in formulating clinical predictions merits further study. The findings also suggest that weighing information such as self-report of pain severity and injury type might further enhance the practitioner's ability to predict return to work.

An outbreak of Campylobacter jejuni infection in a neonatal intensive care unit.

During a period of 2 weeks Campylobacter jejuni infection was diagnosed in seven infants in a neonatal intensive care unit. An identical serotype of Camp. jejuni was found in five of the cases. Investigations suggested that a common source of infection or infection acquired from mothers during delivery were unlikely. The dates of onset and the common serotype indicate that the outbreak may have been caused by person-to-person spread.

Soft tissue calcification: a complication of vitamin E injection.

Two cases of gross soft tissue calcification following intramuscular administration of vitamin E in two premature babies are described. The drug was administered for prevention of retinopathy of prematurity. The relation between this complication and both the dosage used and the duration of the treatment is discussed. In spite of the extent of the calcifications, a benign course was observed. Other reports about this complication are reviewed.

Primary and familial hypoalphalipoproteinemia.

Our specific aim was to assess within-family clustering of high-density lipoprotein cholesterol (HDLC) levels in kindreds identified through probands with primary hypoalphalipoproteinemia, and to determine whether, and to what degree, familial aggregation of HDLC less than or equal to the tenth percentile represents a heritable trait, familial hypoalphalipoproteinemia. Our probands were selected arbitrarily by virtue of HDLC less than or equal to the age-sex-race-specific tenth percentile as the sole dyslipoproteinemia, with an additional requirement that they be normotriglyceridemic (triglyceride levels less than the 90th percentile). The probands were also required to have primary hypoalphalipoproteinemia, not secondary to diseases and/or drugs. Fifteen of the 16 probands were men; 12 were referred because of premature myocardial infarction, angina, or stroke, 2 because of family history of premature myocardial infarction or stroke, and 2 because of low HDLC observed on routine health examinations. Two of the 16 kindreds exhibited three-generation vertical transmission of bottom decile HDLC. In three kindreds, there was also three-generation vertical transmission of bottom decile HDLC, but top decile triglycerides accompanied bottom decile HDLC in one or more generations. Eight kindreds displayed two-generation vertical transmission of bottom decile HDLC. After excluding probands, there were 11 critical matings (bottom decile HDLC by normal), with 30 living offspring, all of whom were sampled. Of these 30 offspring, 13 had bottom decile HDLC, 17 had HDLC greater than tenth percentile. The ratio of offspring with bottom decile HDLC to those of HDLC greater than tenth percentile was 13:17 (0.76/1), not significantly different from the ratio of 1/1, the ratio predictive of a dominant trait, X2(1) = 0.53, P greater than 0.4. The nearly 1:1 segregation ratio for the group of offspring was not due to the aggregation of sibships with, in general, most of the sibs, or none of the sibs affected; within-family expression of low HDLC was also not sex-linked. The 13 hypoalphalipoproteinemic offspring of 11 critical matings included only two subjects whose bottom decile HDLC was accompanied by top decile triglyceride. Our data suggests that not only (by selection) was low HDLC in the probands the sole dyslipoproteinemia, but that the segregation of low HDLC in offspring of critical matings was primarily accounted for by isolated low HDLC, not by hypoalphalipoproteinemia secondary to hypertriglyceridemia. Familial hypoalphalipoproteinemia is a heritable disorder with a pattern of transmission not significantly different from that expected by a hypothesis of mendel

The role of actin sulfhydryls in actin-myosin interaction.

Rabbit white skeletal and dog cardiac actins combined fully with the heavy meromyosins at 4 degrees C and low ionic strength (10.03); the complexes (actin-heavy meromyosin) were mostly in a heavy component which settled rapidly during rotor acceleration. Increasing the temperature to 24 degrees C favored formation of the heavy component while increasing the ionic strength to 10.3 decreased formation of the heavy component. Modification of actin with p-mercuribenzoate (PCMB) generally reduced the heavy component and viscosity but did not interfere with actin-heavy meromyosin combination. Modification with iodoacetamide or N-ethylmaleimide had similar effects. Addition of ATP reduced viscosity and eliminated the heavy component at levels which partially dissociated actin-heavy meromyosin. Modification of heavy meromyosin with PCMB inhibited combination with actin. The characteristics of interaction of the cardiac proteins varied less with temperature but more with ionic strength than those of skeletal proteins.