Primary structure and reactive site of a novel wheat proteinase inhibitor of subtilisin and chymotrypsin

The proteinase inhibitor WSCI, active in inhibiting bacterial subtilisin and a number of animal chymotrypsins, was purified from endosperm of exaploid wheat (Triticum aestivum, c.v. San Pastore) by ion exchange chromatography and its complete amino acid sequence was established by automated Edman degradation. WSCI consists of a single polypeptide chain of 72 amino acid residues, has a molecular mass of 8126.3 Da and a pl of 5.8. The inhibition constants (Ki) for Bacillus licheniformis subtilisin and bovine pancreatic alpha-chymotrypsin are 3.92 x 10(-9) M and 7.24 x 10(-9) M, respectively. The inhibitor contains one methionine and of tryptophan residue and has a high content of essential amino acids (41 over a total of 72 residues), but no cysteines. The primary structure of WSCI shows high similarity with barley subtilisin-chymotrypsin isoinhibitors of the Cl-2 type and with maize subtilisinchymotrypsin inhibitor MPI. Significant degrees of similarity were also found between sequences of WSCI and of other members of the potato inhibitor I family of the serine proteinase inhibitors. The wheat inhibitor WSCI has a single reactive site (the peptide bond between methionyl-48 and glutamyl-49 residues) as identified by affinity chromatography and sequence analysis.     

Antimicrobial activity of Mitracarpus scaber extract and isolated constituents

The antimicrobial activity of a methanol extract and isolated constituents of Mitracarpus scaber, a species used in folk medicine by West African native people, was evaluated against Staphylococcus aureus and Candida albicans strains. The mitracarpus methanol extract possesses both antibacterial and antimycotic activities (minimum inhibitory concentration-MIC 31.25 and 62.50 microg ml-, respectively). This extract was subsequently fractioned and monitored by bioassays leading to the isolation of seven compounds screened for antibacterial and antimycotic activities. Among these compounds, gallic acid and 3,4,5-trimethoxybenzoic acid inhibited the growth of Staph. aureus (MIC 3.90 and 0.97 microg ml-). 4-Methoxyacetophenone and 3,4,5-trimethoxyacetophenone effectively inhibited C. albicans (MIC 1.95 microg ml-). The other compounds (kaempferol-3-O-rutinoside, rutin and psoralen) which were also isolated showed low antibacterial and antimycotic activities (125-500 microg ml-).     

Long-term results with growth hormone therapy in idiopathic hypopituitarism

More than 30 years after its introduction, growth hormone (GH) treatment is well established in children with GH deficiency. Nevertheless, the long-term results of this therapy, expressed as height, are generally considered unsatisfactory. We report on results obtained in a group of GH-deficient children who were treated with daily injections of recombinant GH within the first 5 years of life and who reached an adult height very close to their target height. The full catch-up growth to the target height demonstrated in these patients suggests that replacement therapy should be started early and continued until adulthood. Height at onset of puberty is an important variable which might significantly influence the adult height. The significant and prolonged influence of birth weight on growth response to GH therapy underlines the important role of fetal growth in planning early treatment of GH-deficient children.     

Somatic embryogenesis and plant regeneration from undeveloped ovules and stigma/style explants of sweet orange navel group [ Citrus sinensis (L.) Osb.]

Somatic embryogenesis was induced and plant regeneration was obtained in 11 different genotypes of sweet orange navel group [Citrus sinensis (L.) Osb.] from cultures of stigma/style explants and undeveloped ovules. Explants were cultured on 3 different modifications of Murashige and Skoog medium: 500 mg l-1 malt extract; 500 mg l-1 malt extract and 4.6 μM kinetin; and 500 mg l-1 malt extract and 13.3 μM 6-benzylaminopurine. Sucrose (146 mM) was used as carbon source. Somatic embryogenesis occurred 1–3 months after culture initiation from undeveloped ovule and stigma/style cultures of all the genotypes tested. Somatic embryos developed into plantlets with a high frequency (74%) after transfer to Murashige and Skoog medium supplemented with 146 mM sucrose and 500 mg l-1 malt extract. Plants were successfully transferred to soil. This revised version was published online in June 2006 with corrections to the Cover Date.     

The Application of the Tissue Microarray (TMA) Technology to Analyze Cerebral Organoids

“Multi-Omics” technologies have contributed greatly to the understanding of various diseases by enabling researchers to accurately and rapidly investigate the molecular circuitry that connects cellular systems. The tissue-engineered, three-dimensional (3D), in vitro disease model “organoid” integrates the “omics” results in a model system, elucidating the complex links between genotype and phenotype. These 3D structures have been used to model cancer, infectious disease, toxicity, and neurological disorders. Here, we describe the advantage of using the tissue microarray (TMA) technology to analyze human-induced pluripotent stem cell–derived cerebral organoids. Compared with the conventional processing of individual samples, sectioning and staining of TMA slides are faster and can be automated, decreasing labor and reagent costs. The TMA technology faithfully captures cell morphology variations and detects specific biomarkers. The use of this technology can scale up organoid research results in at least two ways: (1) in the number of specimens that can be analyzed simultaneously and (2) in the number of consecutive sections that can be produced for analysis with different probes and antibodies.     

Effect of High-Fidelity Simulation on Medical Students’ Knowledge about Advanced Life Support: A Randomized Study

High-fidelity simulation (HFS) is a learning method which has proven effective in medical education for technical and non-technical skills. However, its effectiveness for knowledge acquisition is less validated. We performed a randomized study with the primary aim of investigating whether HFS, in association with frontal lessons, would improve knowledge about advanced life support (ALS), in comparison to frontal lessons only among medical students. The secondary aims were to evaluate the effect of HFS on knowledge acquisition of different sections of ALS and personal knowledge perception. Participants answered a pre-test questionnaire consisting of a subjective (evaluating personal perception of knowledge) and an objective section (measuring level of knowledge) containing 100 questions about algorithms, technical skills, team working/early warning scores/communication strategies according to ALS guidelines. All students participated in 3 frontal lessons before being randomized in group S, undergoing a HFS session, and group C, receiving no further interventions. After 10 days from the end of each intervention, both groups answered a questionnaire (post-test) with the same subjective section but a different objective one. The overall number of correct answers of the post-test was significantly higher in group S (mean 74.1, SD 11.2) than in group C (mean 65.5, SD 14.3), p = 0.0017, 95% C.I. 3.34 – 13.9. A significantly higher number of correct answers was reported in group S than in group C for questions investigating knowledge of algorithms (p = 0.0001; 95% C.I 2.22–5.99) and team working/early warning scores/communication strategies (p = 0.0060; 95% C.I 1.13–6.53). Students in group S showed a significantly higher score in the post-test subjective section (p = 0.0074). A lower proportion of students in group S confirmed their perception of knowledge compared to group C (p = 0.0079). HFS showed a beneficial effect on knowledge of ALS among medical students, especially for notions of algorithms and team working/early warning scores/communication.     

High Sodium and Low Potassium Intake among Italian Children: Relationship with Age,Body Mass and Blood Pressure

Background

Hypertension is the leading cause of death in developed countries and reduction of salt intake is recommended as a key preventive measure.

Objective

To assess the dietary sodium and potassium intakes in a national sample of Italian children and adolescents and to examine their relationships with BMI and blood pressure (BP) in the framework of the MINISAL survey, a program supported by the Italian Ministry of Health.

Population and Methods

The study population included 1424 healthy subjects (766 boys, 658 girls) aged 6-18 years (mean age: 10.1±2.9) who were consecutively recruited in participating National Health Service centers in 10 Italian regions. Electrolyte intake was estimated from 24 hour urine collections tested for completeness by the concomitant measurement of creatinine content. Anthropometric indices and BP were measured with standardized procedures.

Results

The average estimated sodium intake was 129 mmol (7.4 g of salt) per day among boys and 117 mmol (6.7 g of salt) among girls. Ninety-three percent of the boys and 89% of the girls had a consumption higher than the recommended age-specific standard dietary target. The estimated average daily potassium intakes were 39 mmol (1.53 g) and 36 mmol (1.40 g), respectively, over 96% of the boys and 98% of the girls having a potassium intake lower than the recommended adequate intake. The mean sodium/potassium ratio was similar among boys and girls (3.5 and 3.4, respectively) and over 3-fold greater than the desirable level. Sodium intake was directly related to age, body mass and BP in the whole population.

Conclusions

The Italian pediatric population is characterized by excessive sodium and deficient potassium intake. These data suggest that future campaigns should focus on children and adolescents as a major target in the framework of a population strategy of cardiovascular prevention.     

A Unifying Organ Model of Pancreatic Insulin Secretion

The secretion of insulin by the pancreas has been the object of much attention over the past several decades. Insulin is known to be secreted by pancreatic β-cells in response to hyperglycemia: its blood concentrations however exhibit both high-frequency (period approx. 10 minutes) and low-frequency oscillations (period approx. 1.5 hours). Furthermore, characteristic insulin secretory response to challenge maneuvers have been described, such as frequency entrainment upon sinusoidal glycemic stimulation; substantial insulin peaks following minimal glucose administration; progressively strengthened insulin secretion response after repeated administration of the same amount of glucose; insulin and glucose characteristic curves after Intra-Venous administration of glucose boli in healthy and pre-diabetic subjects as well as in Type 2 Diabetes Mellitus. Previous modeling of β-cell physiology has been mainly directed to the intracellular chain of events giving rise to single-cell or cell-cluster hormone release oscillations, but the large size, long period and complex morphology of the diverse responses to whole-body glucose stimuli has not yet been coherently explained. Starting with the seminal work of Grodsky it was hypothesized that the population of pancreatic β-cells, possibly functionally aggregated in islets of Langerhans, could be viewed as a set of independent, similar, but not identical controllers (firing units) with distributed functional parameters. The present work shows how a single model based on a population of independent islet controllers can reproduce very closely a diverse array of actually observed experimental results, with the same set of working parameters. The model’s success in reproducing a diverse array of experiments implies that, in order to understand the macroscopic behaviour of the endocrine pancreas in regulating glycemia, there is no need to hypothesize intrapancreatic pacemakers, influences between different islets of Langerhans, glycolitic-induced oscillations or β-cell sensitivity to the rate of change of glycemia.