Texture evolution of “Amaretti” cookies during storage

The results of a study on texture evolution during 35 days of storage of amaretti, a typical Italian cookie, packaged in two different ways are reported. Amaretti cookies were wrapped in polyvinylchloride (PVC) film or aluminium foil (ALL), to simulate two different permeability conditions and stored at controlled temperature and humidity. Evolution of texture (such as hardness) and a_w were tested instrumentally by a texture analyser and a hygrometer, respectively. Texture was assessed by a cut and puncturing test. Indices for hardening were the area under the curve (N mm) and gradient (N/mm) for the puncturing test and maximum force (N) for the cut test. Both textural tests showed significantly higher hardening of PVC cookies, compared to the ALL cookies. The latter retained good sensorial properties at the end of the storage period, although their internal structure changed from soft and moist to mealy, while the PVC cookies were no longer edible only 10 days after baking. a_w values decreased and increased in PVC and ALL lots, respectively. The results suggest that hardening may be explained by water loss in PVC and moisture redistribution in ALL.     

Persistent thrombin generation in humans during specific thrombin inhibition with hirudin

BACKGROUND: The degree to which antithrombotic drugs suppress thrombin generation is unknown. Because hirudin, unlike antithrombin III, binds intravascular thrombin rapidly and selectively to yield a circulating inactive complex of 3- to 4-hour half-life, we used intravenous hirudin in humans to investigate the course of thrombin generation during and early after anticoagulation with this potent, direct antithrombin. METHODS AND RESULTS: Intravascular thrombin was measured with an ELISA for the thrombin-hirudin complex formed during and for 18 hours after stopping a 6-hour infusion of hirudin at 0.1, 0.2, and 0.3 mg.kg-1.h-1 in three groups of six patients each. With free hirudin in 20- to 10,000-fold molar excess of thrombin and peak activated partial thromboplastin times of 2.3 to 3.0 times baseline, mean plasma thrombin-hirudin complex increased from 794 +/- 85 pg/mL (mean +/- SEM) 15 minutes after the start of the infusion to 1617 +/- 151 pg/mL at 6 hours of infusion to 2667 +/- 654 pg/mL at 24 hours. During the 24-hour observation period, plasma concentration of fragment 1.2 (the peptide released during conversion of prothrombin to thrombin) never fell below baseline but rather increased transiently during the hirudin infusion. Plasma concentrations of thrombin-antithrombin III complex (in ng/mL) decreased from 4.34 +/- 0.40 at baseline to 1.64 +/- 0.13 at 6 hours (P < .001) and gradually increased after stopping the infusion to 5.7 +/- 0.87 at 24 hours (nonsignificant compared with baseline). CONCLUSIONS: Measurement of thrombin-hirudin complex may be used as a marker of thrombin generation in humans. Persistent accumulation of thrombin-hirudin complex and generation of fragment 1.2 during and after completion of potent anticoagulation with hirudin suggest thrombin generation is not blocked by high-affinity thrombin inhibition. The persistent formation of thrombin during declining plasma levels of hirudin may contribute to the pathogenesis of rethrombosis early after antithrombin therapy or during inadequate anticoagulation.     

Epilepsy in very preterm infants: neonatal cranial ultrasound reveals a high-risk subcategory

Osteoporotic fractures, and in particular, hip fractures result in significant morbidity and mortality. Low bone mass is the main risk factor of enhanced bone fragility, resulting in an increased risk for hip fracture. Bone density of osteoporotic women with and without hip fractures show a considerable overlap. Therefore, other bone-independent factors also play an important role for the development of hip- and other osteoporotic fractures. One other important factor is falling. In 90% of hip fractures falling was involved [10-15], but only 5% or less of these falls resulted in a subsequent fracture. The view that adequate exercise is beneficial for skeletal health of children and for prevention and treatment of osteoporosis in adults is supported primarily by two lines of evidence: longitudinal and cross-sectional trials in children and young adult athletes showing a significant increase of muscle- and bone mass after strenuous (children) or chronic exercise (athletes) as compared to normally active (children) or sedentary control subjects. What are the potential benefits and limits of specific exercise programs with respect to bone mass, prevention of falls and fractures? In this review these questions are discussed and a specific exercise program in osteoporotic patients with fractures is delineated.     

Mechanism of Rab geranylgeranylation: formation of the catalytic ternary complex

Rab proteins are geranylgeranylated on one or two C-terminal cysteines by Rab geranylgeranyl transferase (RabGGTase). The reaction is dependent on a Rab-binding protein, termed Rab escort protein (REP). Here, we studied the role of REP in the geranylgeranylation reaction. We first characterized the interaction between REP and ungeranylgeranylated Rab using analytical ultracentrifugation and a fluorescence-based assay. We measured an equilibrium dissociation constant of 0.2 microM for the formation of a 1:1 REP-Rab complex and showed that this interaction relies mostly on ionic bonds and does not involve the two C-terminal cysteine residues. Second, we show that REP is required for recognition of Rab by RabGGTase and therefore that the REP-Rab complex is the true substrate for RabGGTase. Third, we show that free REP inhibits the geranylgeranylation reaction, suggesting that the complex is recognized by RabGGTase primarily via a REP-binding site. Our data suggest a model whereby REP behaves kinetically as an essential activator of the reaction.     

Distraction osteogenesis for lengthening of the hard palate: Part I. A possible new treatment concept for velopharyngeal incompetence. Experimental study in dogs

Many procedures have been described to correct velopharyngeal incompetence. Significant complications can occur, and the results may not be satisfactory. If the short soft palate has satisfactory muscle function and if it could be moved toward the posterior pharyngeal wall by distraction osteogenesis of the hard palate, an entirely new concept of treatment for velopharyngeal incompetence would be available. The object of the present study was to explore the possibility of osteogenesis occurring in the hard palate in dogs after gradual distraction (callus distraction). Six adult, mix-bred dogs were anesthetized, and the palatal mucosa was elevated. A midpalatal transverse osteotomy and two lateral osteotomies were performed. Tantalum bone markers for cephalometric analysis were placed, and an individually fabricated, orthodontic-like distraction device with an expansion screw in the sagittal direction was inserted. The device was stabilized on the premolars and fixed to the palatal bone with titanium miniscrews. Gradual distraction began after a latency period of 10 to 18 days. The rate of the distraction varied from 0.25 to 0.75 mm per day. The device was left in place for 6 to 8 weeks after expansion to allow for bony consolidation. Assessment was by direct examination, cephalograms, computed tomography, and histology with bone labeling. Impressions of the jaws were taken preoperatively and after device removal to examine plaster cast changes in the dental occlusion. Cephalometric and computed tomographic scan analysis demonstrated a distraction of up to 8 mm. All gaps were filled with de novo osteogenesis. Comparison of the plaster casts revealed no change in the occlusion. At 1 month after distraction, the computed tomographic scan showed the first signs of ossification of the experimental gap from the anterior and posterior bone ends. After 4.5 months ossification was almost complete with a small translucent zone in the middle of the experimental gap. After 7 months ossification was complete.     

A comparison of transesophageal and transthoracic echocardiographic assessment of left ventricular function in pediatric patients with congenital heart disease

OBJECTIVE: To determine the quantitative utility of transesophageal echocardiographic assessments of left ventricular function in pediatric patients with congenital heart disease by evaluating the variability between observers and between echocardiographic windows. DESIGN: Retrospective, blinded analysis. SETTING: University-associated pediatric hospital. PARTICIPANTS: Transthoracic and transesophageal echocardiographic images of 25 pediatric patients with congenital heart disease were reviewed. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: End-diastolic area, end-systolic area, and fractional area change were measured from short-axis images of the left ventricle at the midpapillary level by two separate investigators. These measurements were compared by the method of Bland and Altman and Sheiner and Beal. Significant differences in measurements of end-diastolic and end-systolic area by different observers were noted, but they were systematic. A similar situation was noted for the comparison of transthoracic and transesophageal measurements of end-diastolic and end-systolic area. In the comparison of fractional area change between observers or windows, bias and absolute prediction error were lower, with 95% confidence limits of bias or absolute prediction error of 10% or less. CONCLUSIONS: The potential error in the measurement of fractional area change in 10% under optimal conditions. This would suggest that the assessment of ventricular function in the operating room or intensive care unit, under less than optimal conditions, should be viewed as a qualitative, rather quantitative, measurement. There may be significant interobserver and interwindow variability.