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Introduction: Stress and environmental perturbations influence postnatal brain development and may account for the high disability rates of preterm survivors following intensive care treatment. This study aims to investigate the impact of early environmental factors on the monoaminergic neurotransmitter system in the developing rat brain by using an innovative neonatal stress model., Materials and Methods: After birth, in the experimental groups newborn rats were separated from their mothers and exposed to different stressful stimuli four times a day on day P0 to P6 for 10 min each. To mimic intensive care treatment, the stress protocol applied environmental factors like bright light, noise, and low temperature alternating with pain and handling stress at day- and night-time in a varying sequence. The non-stressed control mothers and litters were left completely undisturbed until sacrificing on day P7 or P20., Results: Brains of stressed animals revealed significantly higher levels of norepinephrine (NE) and dopamine (DA) as determined by HPLC-ED and electrochemical detection at day P7 as compared to controls. When returned to their mothers' undisturbed care, juvenile rats at day P20 still showed higher (yet statistically not significant) concentrations of NE and DA in brain. The stressed animals gained less weight with significantly lower body weights at day P7 compared to controls. Their mothers developed various forms of stressed behaviour., Conclusions: A novel animal model for postnatal intensive care stress was established leading to changes in brain monoamine levels of newborn rats, while undisturbed maternal care seems to moderate the stress effects subsequently., (Copyright © 2011 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.)

Congenital pseudarthrosis of the tibia (CPT) is caused by an ill-defined, segmental disturbance of periosteal bone formation leading to spontaneous bowing, followed by fracture and subsequent pseudarthrosis in the first 2 years of life. The results of conventional treatment modalities (e.g., bracing, internal and external fixation and bone grafting) are associated with high failure rates in terms of persisting pseudarthrosis, malunion and impaired growth. As a more promising alternative, a more aggressive approach, including wide resection of the affected bone, reconstruction with free vascularised fibula grafts from the healthy contralateral leg and stable external fixation at a very early stage has been suggested. Between 1995 and 2007, 10 children (age 12-31 months, median 20 months) suffering from CPT were treated at our institutions according to this principle. Two patients were treated before a fracture had occurred. The length of the fibula graft was 7-9cm. End-to-end anastomoses were performed at the level of the distal tibia stump. The follow-up was 80 months (median, range 12 months to 12 years). Radiologic examination at 6 weeks postoperatively showed normal bone density and structure of the transplanted fibula in all cases and osseous consolidation at 19 of the 20 graft/tibia junctions. One nonunion was sucessfully treated with bone grafting and plate osteosynthesis. Pin-tract infection occurred in three patients. Five children sustained graft fractures that were successfully treated with internal or external fixation. Two patients developed diminished growth of the affected limb or foot; all others had equal limb length and shoe size. At long-term follow-up, tibialisation of the transplant had occurred, and normal gait and physical activities were possible in all children. We conclude that in spite of a relatively high complication rate and the reluctance to perform free flap surgery in infants at this young age, the present concept may successfully prevent the imminent severe sequelae associated with CPT., (Copyright 2009 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.)

The Point Contact-Fixator (PC-Fix) was designed as part of the developmental evolution of more biological devices for internal fixations. It is a device characterized by minimal contact to the underlying periosteum and bone, hereby minimizing potential damage to perfusion. A multicentre handling test was conducted in 1993 and 1994 in six hospitals to assess its performance. A total of 83 fractured forearm bones (34 radii and 49 ulnae) in 52 patients were stabilized with a PC-Fix. The mean age of the patients was 37 years. There were 24 AO type A, 24 type B and 5 type C fractures. Nine fractures were open. Mean follow-up was 15.6 months; follow-up was 100%. All 21 surgeons involved considered the use of the PC-Fix self-explanatory and relatively easy. Handling difficulties were mainly related to insertion of the monocortical screws. In particular, the precision required for insertion, the inability to incline the screw and the inability to pull the plate to the bone using the screw were considered hard to deal with. Stripping of the hexagonal slot was a problem at removal of the implant, possibly related to overtightening of the screws at insertion. In 76 of 83 bones (49 of 53 forearms), the fractures united without additional surgery. The healing pattern typically showed early callus formation bridging the fracture, followed by progressive mineralization of the central radiolucent line. Complications included one infection, one late displacement and four delayed unions, all requiring revision surgery. In 8 forearms, plate removal was performed after a mean of 10.3 months. Two refractures occurred after removal of the implant 6 and 7 months postoperatively. In conclusion, the practical handling of the new implant was straightforward and easily learnt. The treatment failures observed were related to technical and strategic errors. We consider that, when using devices with a locking compression principle, a minimum number of three screws should be placed on each side of the fracture, that interfragmentary compression of simple fractures is desirable in order to increase stability and that, contrary to in vivo animal studies, early plate removal is not indicated. The trend in fracture fixation is to improve the biomechanical and biological properties of operating technique and the devices used. The PC-Fix has proven a useful step in the right direction in this evolutionary process.

Between January 1980 and December 1989, 133 consecutive patients were treated for a fracture of the shaft of one or both forearm bones (134 forearms in total). All fractures were stabilized with AO/ASIF 3.5 mm stainless-steel dynamic compression plates. The 1 year follow-up rate was 99 per cent; the long-term follow-up rate was 92 per cent (the mean long-term follow-up was 10.2 years (range, 2.7-15.2)) so there were 96 men and 35 women, with an average age of 37.5 years (range, 16-63). Twenty-two per cent of the forearms had open fractures, 26 per cent of patients had sustained multiple injuries and 19 per cent had a head injury. One hundred and twenty-seven of 132 forearms (96.2 per cent) underwent problem-free consolidation before 6 months. Two delayed unions and two non-unions required reoperation. There was one superficial infection in a patient with a closed fracture. Plates were removed from 70 patients (53 per cent) at a mean of 33.1 months (range, 8-122) after the first operation. In this group, there were three refractures (4.3 per cent) occurring at a mean of 8.7 months (range, 0-14) after plate removal. This study confirms the safety and efficacy of plate osteosynthesis in forearm shaft fractures: a high union rate and low complication rate can be anticipated. The data presented form the most reliable information on this subject currently available with the longest and highest rate of follow up of a sufficient number of patients using a single implant system in a single institution.

The purpose of this project was to verify the value of perfused periosteum as a possibly ideal bed for autogenous cancellous bone graft. The model consisted of a 7 cm defect in the sheep tibia, stabilized with a locked intramedullary nail. The defect was filled with conventional cortico-cancellous bone graft covered either with a muscle or a perfused osteoperiosteal flap. The incorporation of the graft was analysed by a series of radiological and mechanical examinations. The graft embedded in perfused osteo-periosteum was rapidly remodelled to a strong, circular bone. Mechanical testing revealed even better values than for normal bone. The graft embedded in muscle showed an important resorptive phase before scanty, incomplete, reconstitution of bone appeared. Mechanical properties were poor. The study supports the hypothesis that perfused osteo-periosteum is an ideal bed for cancellous bone graft and that perfused muscle is not the ideal environment for incorporation of the graft.

3,4,5-Triiodobenzoic acid, known as auxin transport inhibitor, stimulates specific [3H]verapamil binding to zucchini microsomes by 100% (EC50 = 1 microM). This stimulatory effect is due to a decrease of the apparent equilibrium dissociation constant KD for verapamil from 60 nM to 33 nM without significantly changing the maximum number of binding sites. 3,4,5-Triiodobenzoic acid also increases specific [3H]verapamil binding to rabbit skeletal muscle membranes (EC50 greater than or equal to 20 microM) without affecting [3H]nitrendipine and [3H]-d-cis-diltiazem binding. If 3,4,5-triiodobenzoic acid is added to isolated rings of rabbit A. saphena contracted by potassium depolarization, a dose-dependent relaxation is observed with an IC50 value of about 8 microM. Contractions initiated by the addition of 3 microM norepinephrine can also be abolished by 3,4,5-triiodobenzoic acid with half maximal inhibition at 40 microM.

Determination and quantitation by mass spectrometry can be difficult for compounds in complex biological mixtures where chromatographic interferences are frequently encountered. A gas chromatographic-mass spectrometric system is described which utilizes reverse spectral search and retention time screening to provide a high degree of compound specificity. Computer control of instrument operation, and of data acquisition, analysis and printout allows technologist operators to obtain highly reliable, precise quantitative results using relatively crude sample preparation procedures and short chromatographic times.