Kinematics and dynamics of the auto-rotation of a model winged seed.

Numerical simulations of the auto-rotation of a model winged seed are presented. The calculations are performed by solving simultaneously the Navier-Stokes equations for the flow surrounding the seed and the rigid-body equations for the motion of the seed. The Reynolds number based on the descent speed and a characteristic chord length is varied in the range 80-240. Within this range, the seed attains an asymptotic state with finite amplitude auto-rotation, while for smaller values of the Reynolds number no auto-rotation is observed. The motion of the seed is characterized by the coning and pitch angles, the angular velocity and the horizontal translation of the seed. The values obtained for these quantities are qualitatively similar to those reported in the literature in experiments with real winged seeds. When increasing the Reynolds number, the seed tends to rotate at higher speeds, with less inclination with respect to the horizontal plane, and with a larger translation velocity. With respect to the aerodynamic forces, it is observed that, with increasing Reynolds number, the horizontal components decrease in magnitude while the vertical component increases. The force distribution along the wing span is characterized using both global and local characteristic speeds and chord lengths for the non-dimensionalisation of the force coefficients. It is found that the vertical component does not depend on the Reynolds number when using local scaling, while the chordwise component of the force does.

[Discharge from hospital: how to improve continuity of medical care?]. / Au sortir de l'hôpital, comment renforcer la continuité de la prise en charge médicale?

Early readmission is the major success indicator of the transition between hospital and home. Patients admitted with heart failure reach a 20% rate. Potentially avoidable readmissions, defined as unpredictable and related to a known condition during index hospitalization, represent the improvement margin. For these latter, implementation of specific interventions can be effective. Complex interventions on transition, including several modalities and seeking to encourage patient autonomy seem more effective than others. We describe two models: a pragmatic one developed in a regional hospital, and a more complex one developed in a university hospital during the LEAR-HF study. In both cases, it is imperative to work on "medical liability": should it extend beyond discharge up to the threshold of the private practice?

Primary wound closure with a Limberg flap vs. secondary wound healing after excision of a pilonidal sinus: a multicentre randomised controlled study.

PURPOSE: Off-midline procedures seem to be the best method of primary wound closure after excision of a pilonidal sinus. Primary wound closure with a Limberg flap was compared to secondary wound healing. METHODS: From January 2006 to July 2012, 102 patients with given informed consent (mean age 28 years, men 81%) who had excision of a pilonidal sinus in three hospitals in Switzerland were randomised to group L (Limberg flap, n = 51) or to group E (excision only, n = 51). Primary endpoint was duration of incapacity for work. Follow-up was at 3 weeks and at 1 year postoperative (95% follow-up). RESULTS: Both groups were comparable with regard to patient characteristics. The median (range) operation time was 60 (30-80) min in group L vs. 30 (10-75) min in group E (p < 0.001). No significant differences were found in postoperative pain and painkiller intake; pain, percentage of patients at work and overall satisfaction at 3 weeks postoperative; and overall duration of incapacity for work and overall satisfaction at 1-year follow-up. The complication rate was 49% in group L vs. 12% in group E (p < 0.001). Complications in group L were seroma (6%), wound dehiscence (45%), skin necrosis (10%), hematoma (6%), infection (4%) and recurrent disease (13%). Complications in group E were recurrent disease (6%) and wound healing disorder (6%). CONCLUSIONS: After excision of a pilonidal sinus, primary wound closure with a Limberg flap has no advantage over secondary wound healing. The main reason for this conclusion is the relatively high complication rate of primary wound closure with a Limberg flap.

[Treatment of isolated fractures of the olecranon: percutaneous double-screw fixation versus conventional tension band wiring]. / Behandlung von isolierten Olekranonfrakturen: Perkutane Doppelschraubenosteosynthese vs. konventionelle Zuggurtung.

BACKGROUND: Isolated fractures of the olecranon account for 7-10% of all osseous injuries in adults. These fractures are usually treated surgically by conventional tension band wiring. The percutaneous double-screw fixation is an optional treatment in patients with two fragment olecranon fractures with some postoperative advantages. PATIENTS AND METHODS: A total of 13 patients with isolated fractures of the olecranon (Schatzker-Schmelling type A) treated by percutaneous double-screw fixation were included in this prospective study. The mean age of patients was 43.6 ± 11.0 years. Intraoperative and postoperative complications were recorded. Functional results were assessed after a mean follow-up of 38.2 ± 11.5 months using the Quick-DASH score. The results were compared with those obtained in the control group including 26 patients treated by conventional tension band wiring. RESULTS: No intraoperative complications were observed in both groups. In the group with percutaneous double-screw fixation the scar length was significantly shorter (2.4 ± 0.4 cm vs. 11.0 ± 1.8 cm, p < 0.001) and the hardware removal was substantially less frequent that in the group with conventional tension band wiring with 38.5 % and 73.1 %, respectively. At the minimum follow-up of 2 years comparable functional results were obtained in both groups (Quick-DASH score 2.3 vs. 0.0 points, respectively, p = 0.155); however, the range of elbow motion was significantly higher in the group with percutaneous double-screw fixation (extension/flexion 145° vs. 130°, p < 0.001; pronation/supination 165° vs. 155°, p < 0.001). CONCLUSIONS: The percutaneous double-screw fixation is a safe and viable treatment option in patients with isolated fractures of the olecranon (Schatzker-Schmelling type A). The functional results regarding DASH scores obtained using this technique were comparable with those observed in patients with conventional tension band wiring; however, range of elbow motion and cosmetic results were significantly better in the patient group with percutaneous double-screw fixation.

Influence of osteopontin expression on the metastatic growth of CC531 rat colorectal carcinoma cells in rat liver.

Development of hepatic metastasis is responsible for most of colorectal cancer-related deaths. Osteopontin (OPN) is a small integrin-binding N-linked glycoprotein, which plays a crucial role in the formation of hepatic metastasis. This study aimed to suppress Opn expression by an antisense-oligonucleotide (ASO(Opn)) to decrease liver metastasis in vivo. The effect of ASO(Opn) was investigated in vitro in CC531(lacZ) colorectal cancer cells in comparison to sense (SO) or nonsense (NSO) oligomers, by determining mRNA and protein expression levels, as well as cell survival. For in vivo treatment, CC531(lacZ) cells were intraportally inoculated into rats to compare the effects of ASO, SO and NSO oligomers, following prolonged subcutaneous administration by osmotic mini-pumps. The resulting CC531(lacZ) tumor cell load in the liver was measured by a ß-galactosidase assay. Proliferation of CC531(lacZ) cells in vitro was significantly decreased after ASO(Opn) and SO treatment (P<0.001). Liver metastasis development was reduced as long as ASO(Opn) was administered, but this effect was rapidly blunted following the end of the ASO(Opn) administration. In contrast, administration of the SO resulted in a tumor load reduction, which surprisingly surpassed the ASO(Opn) effect in vivo in terms of a long-lasting metastasis suppression, which was accompanied with increased survival of the animals. Administration of the ASO(Opn) in rats was effective in decreasing their liver metastasis. The short-lived effect might be extended by modifications suited to increase the ASOs' half-life. In addition, there was a superior anti-metastatic effect caused by the SO, which has not been reported previously.

Aminoguanidine does not inhibit the initial phase of experimental diabetic retinopathy in rats.

We have previously shown that long-term administration of aminoguanidine, an inhibitor of advanced glycosylation product formation, reduces the extent of experimental diabetic retinopathy in the rat by 85%. In order to determine whether the residual retinopathy that developed despite aminoguanidine was attributable to advanced glycation endproduct formation, a time-course study was performed in three different groups of male Wistar rats: non-diabetic controls (NC), streptozotocin-diabetic controls (DC) and streptozotocin-diabetic rats treated with aminoguanidine HCL, 50 mg/100 ml drinking water (D-AG). Eyes were obtained at 24, 32, 44 and 56 weeks of diabetes/treatment duration and morphologic evaluation was done on retinal digest preparations. At 56 weeks, retinal basement membrane thickness was additionally measured. After 24 weeks of diabetes, the number of acellular capillaries was significantly elevated in DC (44.6 +/- 5.7/mm2 of retinal area, NC 19.6 +/- 4.9; p < 0.001) and increased continuously over time (DC 56 weeks 87.4 +/- 15.1; p < 0.001 vs DC24 weeks). In contrast, acellular capillaries in D-AG increased over the first 24 weeks and then remained constant for the rest of the study (D-AG 24 weeks 35.7 +/- 5.18; p < 0.01 vs NC 24 weeks and NS vs DC 24 weeks; D-AG 56 weeks 42.0 +/- 6.20; p NS vs D-AG 24 weeks).(ABSTRACT TRUNCATED AT 250 WORDS)

[Continuous intravenous infusion of insulin to girls with hereditary tall growth and secretion of human growth hormone, prior to and during Deposiston treatment (author's transl)]. / Intravenöser Insulinbelastungstest und Wachsdtumshormonsekretion bei Mädchen mit konstitutionell-hereditärem Hochwuchs vor und während der Behandlung mit Deposiston.

Continuous intravenous insulin infusion tests, accompanied by growth hormone determination, were applied to 40 girls of tall growth whose final lengths were predicted to be in excess of 181 cm. The girls were aged between nine and half and 14 years and one month, all of them being in the premenarchic phase. The tests were conducted prior to and following at least one year of Deposiston therapy (oestrogen/gestagen). - Really effective inhibition of growth (7.4 +/- 0.6 cm) was obtained only from five girls, aged between nine years and ten months and eleven years, in whom basal secretion of HGH was lower with significance than that of the whole group, with their stimulation reaction being fully retained. Secretion of somatotropic hormone (STH) of the other girls remained unaffected, prior to and following treatment. The weekly oestrogen dose of 1 mg was relatively low, when compared to propositions made by other authors, but it seemed to be justified by the average reduction in expected final body length obtained for the probands reviewed (5.4 +/- 2.0 cm).

PIP: Continuous intravenous insulin infusion tests, accompanied by growth hormone determination, were applied to 40 tall girls whose final heights were predicted to be in excess of 181 cm. The girls, ages 9 1/2 to 14 years 1 month were all premenstrual. Tests were conducted prior to and following at least 1 year of Deposiston therapy (estrogen gestagen). Truly effective inhibition of growth (7.4 + or - 0.6 cm) was seen only in 5 girls ages 9 years 10 months and 11 years in whom basal secretion of HGH was lower than the rest of the group. Their stimulation reaction was fully retained. Secretion of somatotropic hormone of the other girls remained unaffected prior to and following treatment. The weekly estrogen dose of 4 mg was relatively low when compared to administrations reported by other authors but it seemed justified by the average reduction in expected final body height obtained for the subjects reviewed (5.4 + or - 2.0 cm). (Author's modified)