Social media and e-learning use among European exercise science students

With the rise of digital technologies, electronic learning and communication tools are becoming a firm part of academia to promote knowledge of health sciences. This study sought to analyse the attitude of students regarding social media and digital learning for study purposes in sport and exercise science. A survey was carried out with a questionnaire (20 main items) in six sport science faculties, equally spread across Germany (G), Italy (I) and the United Kingdom (UK) between February and October 2017. The focus areas were students' usage of social media (Facebook, Google+, Instagram, LinkedIn, Skype, Twitter, WhatsApp, YouTube) for academic purposes and their use of e-learning. Data were analysed by quantitative and qualitative methods. 229 students participated in the study (G: 68, I: 121, UK: 40). While YouTube was mostly used for receiving knowledge, WhatsApp and Facebook showed additional preferences for peer contacts for learning purposes and knowledge discussions. Preferred online data sources were PubMed (77%), free access journals (67%), YouTube (66%) and Wikipedia (63%). Often used digital learning materials were own universities' PowerPoints (77%), scripts (59%) and scientific articles (53%). However, some preferences showed national differences. The evaluated participants showed an overall high use of social media and e-learning tools for their studies. Students would like more digital learning sources made available to them by their institutions. However, some differences in preferences of digital learning or communication tools may exist and this should be considered for international approaches to promote health knowledge among students.

Using the LHB score for assessment of LHB pathologies and LHB surgery: a prospective study

INTRODUCTION

The long head of biceps tendon (LHB) score was designed to clinically assess LHB pathologies. Purpose of this study was to prospectively assess patients with LHB pathologies preoperatively and after LHB surgery using the LHB score.

MATERIALS AND METHODS

Fifty-seven patients (29 f/28 m, Ø age 61.0 years), showing clinical signs of LHB pathologies, were prospectively included into this study. In 43 patients LHB pathologies could be confirmed intraoperatively. Among these, in 26 patients a biceps tenodesis (group I; 8 f/18 m, Ø age 61.2 years), and in 17 patients a biceps tenotomy was performed (group II; 12 f/5 m, Ø age 64.2 years). In 14 patients no intraoperative correlate concerning the biceps symptoms could be found (group III; 9 f/5m, Ø age 56.8 years). In these patients no further LHB treatment was carried out. The clinical evaluation contained the Constant score (CS) as well as the LHB score preoperatively and 2 years postoperatively.

RESULTS

The CS improved significantly in all the three groups [group I: 41.7 (20-70) to 81.3 (62-100); group II: 42.2 (18-66) to 75.3 (41-84); group III: 45.7 (22-77) to 72.9 (48-85)] (p < 0.05). Also the LHB score increased significantly in all three groups [group I: 74.3 (41-97) to 94.2 (80-100); group II: 73.4 (57-97) to 84.2 (49-100); group III: 71.1 (58-80) to 90.8 (70-100)] (p < 0.05). Compared to group II, group I showed significant better results in the total LHB score and in the cosmetic result (p < 0.05).

CONCLUSIONS

We recommend that patients with LHB pathologies are evaluated using the LHB score, since it provides LHB related information and is a proper tool to assess the clinical outcome after surgery. However, the score is not appropriate to detect LHB pathologies preoperatively.

LEVEL OF EVIDENCE

II.

Form follows function: a computational simulation exercise on bone shape forming and conservation

The present paper explores whether the shape of long bone shafts can be explained as a mere result of mechano-adapation. A computer simulation study was conducted in order to investigate adaptation processes of bone-like structures under load patterns comparable to those acting on the diaphysis of long bones. The aim of the study was to have a deeper look into the relationship between typical loading patterns and resulting bone shape and structure. The simulations are based on a mechanistic model approach for mechano-transduction and bone transformation. Results of the simulations are that axial torsion around the long axis is important for the evolvement and maintenance of tube-like structures. Of note such structures can form from a variety of starting geometries, provided that axial torsion is present. The selection of the set-point parameter for the regulation of load adapted bone transformation has an impact on the final structure as well. In conclusion, the present study confirms the mechanical environment's potential to generate shaft-like structures and demonstrates the respective boundary conditions.

Neonatal respiratory insufficiency caused by an (homozygous) ABCA3-stop mutation: a systematic evaluation of therapeutic options

BACKGROUND

Autosomal recessive ABCA3 (ATP-binding cassette protein A3) gene mutations have been associated with neonatal respiratory distress and pediatric interstitial lung disease. The clinical course of the disease depends on the underlying mutations. Therefore, knowledge of course, symptoms and treatment of the disease is important.

PATIENT AND METHODS

A term newborn suffered from progressive respiratory insufficiency, which led to death at the age of 4.8 months. The girl developed interstitial lung disease. Infections as well as structural and functional disorders of the lung were systematically excluded. A homozygous c.4681C > T (Arg 1561 Stop) mutation of the ABCA3 gene was identified. A literature review of the pathophysiology and treatment options of the disease was done. Therapeutic approaches with corticosteroids, macrolide, and hydroxychloroquine did not improve the clinical course.

RESULTS

Therapeutic strategies for chronic interstitial lung disease have been used successfully in cases of a mild clinical course in juvenile patients with ABCA3 gene mutation. In our patient with homozygous ABCA3 gene mutation,they were not effective. Lung transplantation remains as a therapeutic option, but because of donor organ shortage and associated morbidity and mortality it is rarely feasible.

CONCLUSION

More experience in the treatment of newborns with ABCA3 gene mutations is needed. Randomized, prospective evaluation of the different therapeutic approaches in a specific registry may improve prognosis and treatment of affected individuals.

Simvastatin modulates mouse embryonic stem cell-derived chondrogenesis in vitro

It has been studied in detail that cellular differentiation during chondrogenesis can be recapitulated in vitro by differentiation of embryonic stem (ES) cells as embryoid bodies (EBs). We here used this model system of cartilage development to analyze the effect of simvastatin, a potentially embryotoxic substance. Statins are a group of drugs used to treat hypercholesterolaemia. We found that simvastatin activated cartilage nodule formation during EB differentiation. Extended application of simvastatin resulted in enhanced expression of cartilage marker molecules and prolonged persistence of cartilage nodules. Expression of collagen type II was upregulated during simvastatin-induced chondrogenic ES cell differentiation as demonstrated by quantitative real time PCR. However, immunostaining for cartilage marker molecules revealed that cartilage nodules within simvastatin-treated EBs were defective, bearing cavities of cell loss. Furthermore, caspase activity was reduced in comparison to untreated controls indicating reduced apoptosis. Taken together, we may speculate that simvastatin prolongs survival of chondrocytes and disrupts cellular integrity of cartilage nodules during EB development by affecting apoptotic mechanisms. The study underlines that ES cell-derived EBs are a useful in vitro model to screen substances for their embryotoxic and teratogenic potential.

Deformation Behavior of Polycrystalline MoSi2 Between 495°C and 1250°C

In order to study the deformation processes of reaction-sintered and hot pressed MoSi2, compression tests have been performed and the microstructure of the deformed samples has been investigated by optical, scanning and transmission electron microscopy. At a low strain rate of 2.5× 10−7 S−1 permanent deformation has been achieved at 1250°C. The deformation behaviour is controlled by different microprocesses within different temperature ranges. Below 1000°C, hardening occurs beyond the upper and lower yield points. Inside the grains, dislocations glide at sufficiently high stresses in a homogeneous way as well as in localized slip bands. A plateau in the dependence of the yield stress on temperaturecorresponds to the flow stress anomaly of easy slip systems in single crystals. However, since there are not enough independent slip systems to satisfy the van Mises criterion, the material does not deform homogeneously in all grains. Intergranular and intragranular cracks, which are formed after the yield point, carry an increasing part of strain at decreasing temperatures. Above 1000°C, softening occurs after the yield point. A grain boundary phase flows viscously and carries most of the deformation. Since the grains do not deform themselves, intergranular cracks develop also at high temperatures.

Purification, primary structure, and homology relationships of a chloroplast ribosomal protein

A chloroplast ribosomal protein that showed immunological homology to Escherichia coli ribosomal protein L12 was purified from spinach (Spinacia oleracea) leaves and its primary structure was determined by manual micro Edman degradation. The protein is composed of 130 amino acid residues and has M(r) 13,576. It shows structural features characteristic of the L12 proteins of eubacterial 70S ribosomes (e.g., identical amino acid residues in about 50% of the sequence) but no apparent homology to the L12-type proteins of eukaryotic cytoplasmic 80S ribosomes. The homology to eubacterial proteins is highest in the COOH-terminal region (70%) and low in the NH(2)-terminal region (<20%).

[Gaussian distribution of intelligence in VLBW preterm infants at age 5: very low correlation with very low birth weight]

BACKGROUND

Preterm infants with very low birth weight < 1500 g (VLBW) have a higher risk of developmental disorders. In addition to the common estimation of the mean intelligence values, we studied the distribution of intelligence at preschool age in VLBW infants and the risk factors influencing this distribution.

PATIENTS AND METHODS

A prospective cohort study of 277 VLBW infants < 32 weeks born in 1991-1995 and treated according to a standardized regimen in one Perinatal Center was carried out, including measurement of intelligence (Kaufman-Assessment Battery for Children) at age 5. Statistical methods employed were: explorative data analysis, correlation, chi (2)- and t-tests; the tested variables were: small for gestational age (< third percentile), perinatal acidemia (umbilical arterial pH < 7.10), perinatal hypoxia (BE < - 10), hypothermia (< 36 degrees C), hypoglycemia after the first day of life (< 30 mg / dL), bronchopulmonary dysplasia (FiO (2) > 0.21 > or = 36 weeks), intraventricular hemorrhage, ventricular dilation, periventricular leukomalacia, seizures, abnormal acoustic evoked potentials, and hyperexcitability at discharge.

RESULTS

The distribution of intelligence in 137 VLBW infants < 32 weeks (60 % follow-up rate) was similar to a symmetrical Gaussian bell curve. The intelligence increased very slightly with birth weight (Pearson correlation: 0.172; p = 0.045) and was significantly lower in children with hypoglycemia after the first day of life (- 13.35; 95 % confidence interval: - 20.08 to - 6.63; p = 0.002), hyperexcitability at discharge (- 16.28; 95 % confidence interval: - 25.26 to - 7.31; p = 0.005), and bronchopulmonary dysplasia (- 7.00; 95 % confidence interval - 11.71 to - 2.29; p = 0.039).

CONCLUSIONS

At preschool age, the intelligence of VLBW infants is normally distributed and correlates only slightly with the very low birth weight. Hypoglycemia after the first day of life and bronchopulmonary dysplasia are risk factors for lower intelligence. Hyperexcitability at discharge seemed to represent a promising prognostic factor for a later intelligence reduction.

A new method of monitoring osteomyelitis

Chronic infections of bone such as osteomyelitis are frequent events, especially in immunocompromised or diabetic patients, and costly on a national level. Incorrect treatment or delayed diagnosis may lead to loss of the affected extremity or mandible. The aim of this study was to assess the possible value of urinary lysylpyridinoline (LP) and hydroxylysylpyridinoline (HP) concentrations in the monitoring of mandibular osteomyelitis. Patients were assigned to the following groups: group 1 (n=85), control; group 2a (n=38), patients with active disease; group 2b (n=25), patients of group 2a 6 months after successful treatment; group 2c (n=7), patients of group 2a with ongoing osteomyelitis 6 months after treatment. The range and upper limit of normal values (HP(max) and LP(max)) were determined in group 1. Levels of LP and HP were measured by high-performance liquid chromatography and fluorescence detection. There was a significant decrease (mean 45.43% for HP and 32.12% for LP) in samples of group 2b compared to 2a (P<0.001 for HP and LP). There was a significant increase in HP values in samples from group 2c compared to 2a (P=0.018). The urinary concentrations of HP and LP appear to act as a marker of disease activity, with a decrease reflecting treatment success and an increase or stable values indicating persistent disease. An inexpensive tool (US$5 per analysis) for the monitoring of osteomyelitis is described.

Primary amides. A general nitrogen source for catalytic asymmetric aminohydroxylation of olefins

N-Bromo,N-lithio salts of primary carboxamides have been shown to be efficient nitrogen sources for catalytic asymmetric aminohydroxylation of olefins, behaving much like the parent N-bromoacetamide in these reactions. alpha-Chloro-N-bromoacetamide is a particularly interesting nitrogen source, as it is functionalized for further reaction, including easy deprotection by treatment with thiourea.

Serum androgen levels in adolescents with type 1 diabetes: relationship to pubertal stage and metabolic control

Delayed sexual maturation is still frequently seen in adolescents with type 1 diabetes. A close relationship between insulin and androgen metabolism has been found in a number of studies. Our study was designed to investigate whether or not abnormalities in androgen secretion could play a role in the onset of sexual maturation in adolescents with type 1 diabetes. We have asked whether or not there was a correlation between daily insulin dosage, duration of diabetes, metabolic control, age, pubertal stage, and body mass index (BMI) versus serum androgen concentrations. Basal total and free testosterone, dehydroepiandrosterone-sulfate (DHEA-S), dihydrotestosterone (DHT), sex hormone binding globulin (SHBG) and 3alpha-androstanediol glucuronide (3alpha diol-G) plasma concentrations were measured in 36 pubertal boys and 31 pubertal girls with type 1 diabetes and in 59 sex- and pubertal stage-matched control subjects without diabetes. Significantly higher serum total testosterone (p<0.01) and free testosterone (p<0.05) levels were found in females and males with type 1 diabetes than in controls at pubertal stage 5. DHEA-S, SHBG, DHT and 3alpha diol G concentrations in patients with diabetes were not significantly different from those in controls. There was no correlation between daily insulin requirements and serum androgen levels. These data suggest that adolescents with diabetes have similar serum levels of DHEA-S, SHBG, DHT and 3alpha diol G as healthy subjects at all stages of puberty. However, there are significant differences in serum testosterone and free testosterone levels in adolescents with diabetes when compared to healthy, sex- and pubertal stage-matched controls in late puberty. We hypothesize that the increased testosterone levels in patients with diabetes could relate to reduced fertility in females, disorders of sexual maturation and an increased risk for cardiovascular complications later in life.

[Hearing screening of high risk newborn infants]

OBJECTIVE

This prospective study reports on the prevalence of hearing impairment in an at-risk neonatal intensive care unit (NICU) population.

DESIGN

From 1990 to 1998, 1062 neonates were screened with the use of transitory evoked otoacoustic emissions (TEOAE) and brainstem evoked response audiometry (BERA).

RESULTS

934 infants passed the primary screen for both ears, 75 for one ear, adding up to 95%. 17 infants (1.6%) were lost to follow-up. In fourteen infants (1.3%), bilateral hearing impairment above 30 dB was confirmed. While all children with hearing impairment belonged to the group of 862 children receiving aminoglycosides, only one of them presented no other risk factors. In twelve of the hearing impaired children other anamnestic factors, i.e. dysmorphism, prenatal rubella or cytomegaly, family history of hearing loss or severe peri- and postnatal complications seem to be more probable causes of the identified hearing loss. In one of these children, delayed onset or progression of hearing loss is suspected.

CONCLUSIONS

From our data, aminoglycosides are not an important risk factor for hearing impairment, when serum levels are continuously monitored, as in our cohort. After adjustment for other risk factors, birth weight between 1000 gr and 1500 gr and a gestational age between 29 and 31 weeks were no predictive markers for hearing impairment. It might be speculated that the improved medical treatment in a NICU reduces the probability of hearing impairment for those two groups. Conductive hearing loss as a possible additional cause for hearing impairment was not studied in detail, but the high percentage of malformations detected (four out of fourteen hearing impaired infants) demands further monitoring, close follow-up, adequate treatment and counselling.

Expression of apoptosis and cell cycle related genes in proliferating and colcemid arrested cells of divergent lineage

Progression through the cell cycle and redirection of cells towards programmed cell death (apoptosis) are tightly inter-related processes. However the requirement for tissue and cell type specificity suggests that a wide variety of mechanisms are used to achieve the same purpose. To examine this issue, we investigated cell cycle (c-myc, p53, p21/WAF) and apoptosis related (bcl-2, bcl-X(L), bax-alpha) gene expression in two cell lines of very different origin under proliferating and apoptosis-inducing conditions. Transformed human osteosarcoma cells (MG63) and non-transformed human kidney embryonal fibroblasts (293-0) were kept in culture in medium containing 10% FCS and growth arrest was induced by the addition of 50 ng/ml colcemid. Colcemid treatment caused growth arrest and elevated expression of cyclin B1 protein in both cell lines. Apoptosis was significantly elevated in both cell lines after colcemid exposure for at least one cell cycle. However the pattern of expression of cell cycle and apoptosis related genes, determined by RT-PCR, was quite different between the two cell lines during exponential growth and cell cycle arrest. Colcemid treatment did not markedly influence c-myc, p53 and p21/WAF expression in MG63 cells but did suppress c-myc and increase p21/WAF in 293-0 cells. Furthermore colcemid treated MG63 cells exhibited elevated bcl-2 and bax-alpha expression while similar treatment of 293-0 cells resulted in decreased bcl-X(L) and slightly increased bax-alpha expression. While growth arrest and apoptosis were induced in both MG63 and 293 cells following colcemid treatment, the differences in gene expression suggest that the mechanism by which these cells determine cell fate is quite different and may determine the sensitivity of different cell populations to anti-neoplastic drug therapy. The distinct patterns of gene expression should be carefully defined before mechanisms of apoptotic cell death are studied.

Hearing screening in at-risk neonate cohort

OBJECTIVE

This prospective study reports on the prevalence of hearing impairment in an at-risk neonatal intensive care unit (NICU) population.

DESIGN

From 1990 to 1997, 942 neonates were screened with transient evoked otoacoustic emissions (TEOAE) and brainstem evoked response audiometry (BERA).

RESULTS

835 Infants passed the primary screen for both ears, 57 for one ear, adding up to 94.7%. Seventeen infants (1.9%) were lost to follow-up. In thirteen infants (1.4%), bilateral hearing impairment above 30 dB was confirmed. While all children with hearing impairment belonged to the group of 820 children receiving aminoglycosides, only one presented no other risk factors. In 11 of the hearing impaired children other anamnestic factors, i.e. dysmorphism, prenatal rubella or cytomegaly, family history of hearing loss or severe peri- and postnatal complications seem to be more probable causes of the identified hearing loss.

CONCLUSIONS

From our data, aminoglycosides seem not to be an important risk factor for communication related hearing impairment, when serum levels are continuously monitored, as occurred in our cohort. After adjustment for other risk factors, birth weight between 1000 and 1500 g and a gestational age between 29 and 31 weeks were no predictive markers for hearing impairment. It might be speculated that the improved medical treatment in a Neonatal Intensive Care Unit (NICU) reduces the probability of hearing impairment for those two groups. Conductive hearing loss as a possible additional cause for hearing impairment was not studied in detail, but the high percentage of malformations detected (four out of 13 hearing impaired infants) demands further monitoring, close follow-up, counselling and adequate treatment.

High-Temperature In Situ Straining Experiments in the High-Voltage Electron Microscope

: Design rules are described here for high-temperature straining stages for transmission electron microscopy. Temperatures above 1000 degreesC can be attained by electron bombardment of the specimen grips. Thermal equilibrium can be reached in a short time by carrying off the heat by water cooling. Some applications of this stage are described. Ferroelastic deformation was observed at 1150 degreesC in t' and partially stabilized zirconia, which changes the microstructure for successive dislocation plasticity. In the oxide-dispersion-strengthened alloy INCOLOY MA 956, dislocations are impeded by oxide particles and move smoothly between the particles. At high temperatures, both the resting and traveling times control the average dislocation velocity. In MoSi2 single crystals of a soft orientation, dislocations with 1/2<111> Burgers vectors are created in localized sources and move on {110} planes in a viscous manner. The dislocations in Al-Pd-Mn single quasicrystals are oriented in preferred crystallographic directions and move in a viscous way as well. On the basis of in situ observations, conclusions are drawn for interpreting macroscopic deformation behavior at high temperatures.

Retinopathy of prematurity in infants of birth weight > 2000 g after haemorrhagic shock at birth

BACKGROUND

The risk of retinopathy of prematurity (ROP) is associated with low birth weight and low gestational age. For ROP screening examination is recommended in infants weighing < or = 1500 g or of less than 32 weeks' gestational age.

METHODS

From 1991 ROP screening was performed in 452 premature infants with either a birth weight < or = 1500 g (n = 303) or a birth weight > 1500 g (n = 149) and who required additional oxygen supplementation or underwent surgery with general anaesthesia before estimated term.

RESULTS

Unexpectedly, three infants with birth weights between 2080 and 2325 g and a gestational age of 32 or 33 weeks developed stage 2 or 3 ROP. One of these underwent cryocoagulation. In three infants, preterm birth was induced by sudden placental abruption with severe prenatal blood loss followed by haemorrhagic shock. The umbilical cord packed cell volume was reduced to 0.14-0.19 (normal 0.43-0.63). All three infants underwent surgery with general anaesthesia within the first weeks of life. Of the remaining 449 infants none with a birth weight > 1650 g developed any stage of ROP.

CONCLUSION

Severe prenatal blood loss requiring blood transfusions and surgery with general anaesthesia may induce higher stages of ROP even in infants with birth weights exceeding the usual screening criteria.

[Measuring microcirculation after replantation and revascularization]

Eighty-four patients were evaluated following replantation or revascularization. Extremity function in daily and professional life was altogether satisfactory. Microcirculation investigations in eight patients included thermography, laser-doppler-flowmetry and photoplethysmography. The rewarming period and postocclusive hyperemia after standardized cooling of the upper extremity were determined. In areas of hypesthesia, the rewarming period was clearly delayed. In addition, reactive hyperemia after occlusion of circulation was significantly reduced.

[Digital luminescence radiography of premature and term infants. Possibilities and limitations]

Postmortem images of seven premature and term newborns, acquired with various conventional screen-film combinations and by a digital technique with appropriate radiation exposures, were compared. Images without and with simulated pathology were used in this study. With electronic manipulation of the computed radiographs we obtained well-balanced images with good contrast, and in many cases the artifacts were better visualized than with the conventional screen film. However, in our study no significant dose reduction for this young age group was possible with the digital technique compared with conventional screen film.

[Plaster filling in surgical treatment of enchondroma--a justified therapeutic procedure?]

Enchondroma are the most frequent tumors of the hand. These benign tumours are characterized by slow growth, the lack of clinical symptoms and by accidental discovery. The surgical treatment of enchondroma includes resection of the tumor tissue from the bone matrix, and subsequent filling of the defect with autologous or homologous spongiosa or with sterile plaster of Paris. We showed in a period from 1982 to 1989 that there is no difference with respect to the clinical outcome between our patients receiving autologous spongiosa (n = 25) or plaster filling (n = 35). Owing to its simplicity and lack of additional surgery at the iliac crest, we prefer the method of plaster filling. Animal studies performed by our group have demonstrated that implanted plaster is transformed to spongiosa within four to ten weeks without adverse effects.

[A pragmatic assessment of sense of smell]

A new clinical odour test was developed and validated in a clinical trial including 50 healthy volunteers as well as 35 patients suffering from smell disorders. The aromas were incorporated in an inert gas under disclosure from oxygen, avoiding impairment caused by oxidative transformation. Conventional smell test by Elsberg bottles was used as standard. The spray test proved to be equally effective in discriminating subjects suffering from smell disorders as the standard procedure. Moreover the spray test is feasible and long term constance of the substances is guaranteed.

[Surgical treatment of distal humerus fractures in children]

From 1955 to 1987 414 children with supracondylar fractures of the humerus were treated at the surgical department of the University of Erlangen. Most important for the choice of treatment in supracondylar fractures was the classification of Baumann. 33 children concerning stage I were treated with cuff and collar or cast. Out of 381 patients with stage II and III Baumann's extension was used in 352 children; 29 had to be operated. The operation was indicated in a further 56 children. 20 of these had a lesion of the condylus radialis, 18 of the epicondylus ulnaris, 8 children showed diacondylar, 3 transcondylar lesions, 3 children had injuries of the condylus ulnaris and 4 more children showed splintered fractures. In 234 patients a follow-up was carried out according to the scheme of Morger. In 91% there was an ideal or good late result, in only 2% of the patients the result was unsatisfactory. The majority of distal fractures of the humerus can be treated conservatively with good results; operative treatment does not improve the functional and cosmetic results. It is indicated in complicated forms of fracture, in which satisfying results are not to be expected by conservative treatment.

[Primary and secondary chest wall tumors--diagnosis, therapy and results]

In a retrospective study 51 patients who underwent chest wall resection for malignant chest wall tumors were reviewed. There were 28 male and 23 female patients with ages ranging from 6 to 76 years (average 50). 34 patients had primary malignant neoplasms (including breast and lung) 17 had metastatic tumors. The tumor was located in the ribs in 45 patients and in the sternum in 6. Reconstruction was with prosthetic material in 16 patients and further plastic reconstruction in 10. Aggressive resection for malignant chest wall tumors and reliable reconstruction can be performed safely, and early wide resection proved to be a potentially curative treatment for primary neoplasms.

Correlation of chloroplast and bacterial ribosomal proteins by cross-reactions of antibodies specific to purified Escherichia coli ribosomal proteins

Immunological homology between chloroplast ribosomal proteins (r-proteins) from a higher plant (Spinacia) and bacterial r-proteins was examined using antibodies prepared against 35 purified Escherichia coli r-proteins. Cross-reactions were determined on cellulose acetate gels and on nitrocellulose paper, after electrophoretic transfer of r-proteins from one- and two dimensional polyacrylamide gels, using peroxidase and fluorescein-conjugated second antibodies for detection (immunoblotting). The specificity of positive cross-reactions was confirmed by absorption experiments using purified E. coli r-proteins. Antisera against five proteins of the small subunit and six proteins of the large subunit of E. coli ribosome (i.e. anti-S7, -S9, -S11, -S12, and -S19; anti-L1, -L2, -L3, -L6, -L13, and -L17) gave cross-reactions. As an inference from this work, and a recent study on the synthesis of certain chloroplast r-proteins in isolated chloroplasts (Eneas-Filho, J., Hartley, M. R., and Mache, R. (1981) Mol. Gen. Genet. 184, 484-488), we suggest that chloroplast r-proteins S7 and L2 are encoded in the organelle DNA.

Evolution of obesity in young people in Busselton, Western Australia

The height and weight measurement of 928 young people of Busselton were collected over a period of up to 11 years. The prevalence of obesity was low in early childhood and increased progressively through adolescence and adulthood, so that 9% of male subjects and 16% of female subjects aged 21 years or over, were obese. The prevalence and degree of obesity were both greater in female subjects than in male subjects. Although most obese young adults were not obese in childhood, 50% of those who were obese between the ages of 9 and 14 years were still obese when examined in young adult life, and were at greater risk of becoming obese adults than were their non-obese peers. Most subjects who subsequently became obese young adults were significantly heavier than their non-obese peers at all ages from the age of 6 years.

Reconstitution of 50 S ribosomal subunits from Bacillus stearothermophilus with 5 S RNA from spinach chloroplasts and low-Mr RNA from mitochondria of Locusta migratoria and bovine liver

Reconstitution experiments with 50 S ribosomal subunits from Bacillus stearothermophilus demonstrate that spinach chloroplast 5 S rRNA can be incorporated into the bacterial ribosome and yield biologically active particles, thereby establishing the eubacterial nature of chloroplast 5 S rRNA. In contrast, mitochondria from Locusta migratoria or bovine liver do not appear to contain discrete, low-Mr RNAs, which can replace 5 S rRNA in the functional reconstitution of B. stearothermophilus ribosomes.