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Neonatal brachial plexus palsy remains a problem, even in light of current advances in perinatal care. While many cases resolve spontaneously, the concern remains on the best means of surgical management for restoration of elbow flexion and shoulder reanimation. The present experimental study in an animal model examines the evidence that supports that neonatal brachial plexus injuries result in structural changes in the affected bone. The study suggests that if the microsurgical reinnervation takes place early enough, these changes may be diminished. On the other hand there is no way to identify at birth, which injuries will be permanent and will need surgical repair and which will spontaneously improve.

Objective There are several factors which affect bone growth. One of them is the peripheralnervous system whose effect on the biomechanics has not been extensively studied. The purpose of this study is to assess the effect of peripheral nervous system in bone biomechanics in an experimental rat model. Materials & methods 27 male Wistar rats were used. In all animals, the roots of the right brachial plexus were dissected and after that the animals were divided into three groups A, B and C. The animals were sacrificed six, nine, and twelve months respectively after the denervation. Both humerus were resected and biomechanical analysis was performed. Results According to the findings of the present study the denervated bones sustain less loading before fracture and they become also more elastic. Additionally, in greater time after denervation plastic deformity is noticed. Conclusion Apart from structural changes, the peripheral nerves are responsible for biomechanic changes in the bones such the greater elasticity of the bone and the reduced strength

A Reversed Phase-High Performance Liquid Chromatography/Diode Array Detection method was developed and validated for paracetamol quantification in cell culture fluid from an in vitro Blood Brain Barrier model. The chromatographic method and sample preparation were developed using only aqueous solvents. The column was a XTerra RP18 150 × 4.6mm, 3.5 μm with a guard column XTerra RP18 20 × 4.6 mm, 3.5 μm at 35 °C and the mobile phase was composed by 100% formate buffer 20 mM at pH 4 and flow rate was set at 1 mL/min. The detection was at 242 nm. The sample was injected at 10 μL. Validation was performed using the accuracy profile approach. The analytical procedure was validated with the acceptance limits at ± 10% over a range of concentration from 1 to 58 mg L(-1). The procedure was then used in routine to determine paracetamol concentration in a brain blood barrier in vitro model. Application of the Unither paracetamol formulation in Blood Brain Barrier model allowed the determination and comparison of the transcellular passage of paracetamol at 37 °C and 4 °C, that excludes paracellular or non specific leakage.

Summary Reconstruction of elbow function in severe or late brachial plexus injuries represents a challenge to the reconstructive microsurgeons. The current sophisticated techniques of nerve reconstruction in combination with secondary local or free functional muscle transfers, may offer satisfactory outcome. Latissimus dorsi can be transferred as a pedicled or free muscle to restore elbow function. We present our experience with elbow reanimation in late cases of brachial plexus paralysis utilising latissimus dorsi muscle transfer. From 1998 to 2006 we operated 103 patients with brachial plexus paralysis. Amongst these patients, 21 were late cases and underwent latissimus dorsi muscle transfer for elbow reanimation. Ten patients had free latissimus dorsi transfer for elbow flexion. Free latissimus dorsi muscle was neurotised either directly via three intercostals in three patients or with a nerve transfer procedure using the contralateral seventh cervical nerve root in seven patients. Care was taken to maintain the proper tension to the muscle, which must hold the elbow in static flexion of about 120° at the end of the procedure. Powerful elbow flexion (M4–M4+) or extension (M4) was obtained after the first 3 months in all patients who had an ipsilateral pedicled latissimus dorsi transfer. In the group of free muscle transfers, elbow flexion was seen after 6–8 months. After the initiation of muscle contraction, eight of the patients regained elbow flexion of M3–M4+. Latissimus dorsi muscle transfer is a reliable method for elbow reanimation. Appropriate postoperative management is also an important factor to obtain better outcome.

With the double goal to streamline biomarker discovery of Multiple Sclerosis neuroinflammatory pathology entangled by non-affected Central Nervous System tissue and to better characterize the complex molecular interactions at the altered blood brain barrier (BBB) that becomes permissive to extravasation of blood derived immune cells and compounds, we choose to identify peptide ligands reacting with inflammatory CNS lesions. With no “a-priori” for targets by applying in vivo the phage displayed 12aa peptide screening in CNS neuroinflammation of the experimental autoimmune encephalomyelitis (EAE) rat model of MS and healthy controls, we generated two complex phage displayed peptide repertoires. By developing molecular DNA subtraction of both phage repertoires we generated a subtraction phage repertoire of EAE specific peptides. In a bioinformatics approach aligning the 270,612 EAE peptides to the human proteome the formed peptide clusters allowed the ranking of proteins being potential “mimicked” indicators of functional protein interactions. Experimentally, among the most high score mimicked proteins, derived synthesized short peptides (22aa) of mimicked domains were tested for labeling of BBB alterations in CNS sections of MS and other chronic neurodegenerative diseases. In vitro studies using the BBB model hCMEC/D3 confirmed their binding to human endothelial cells under proinflammatory stimulation. Finally, with a derived peptide covalently linked to a nanocarrier contrast agent, we could target in vivo and monitor by MRI, experimentally induced inflammatory CNS lesions. Our strategy of combining the developed molecular biology and bioinformatics approaches adapted to phage display is applicable to many disease models to identify biomarkers and functional proteins/domains.

Numerous static and dynamic techniques have been described for the management of acute acromioclavicular (AC) joint dislocation. To date, no standard technique has been established and several complications have been described for each of these techniques. The purpose of the present study was to evaluate the functional and radiographic outcomes of acute AC joint reconstruction after a mini-open technique using the double-button fixation system.Twelve patients with acute AC joint dislocation treated with the double-button fixation system by one surgeon were retrospectively reviewed. Functional assessment was performed by an independent reviewer using the DASH, Constant and the VAS scores. The coracoclavicular (CC) distance of the affected shoulder was assessed on a standard radiograph and compared with the contralateral normal one.Eight patients were operated on for grade III AC joint dislocation and 4 for grade IV. The mean age of the patients at the time of surgery was 27.5 years. The mean follow-up was 18.25 months (range: 12-30 months). At the most recent follow-up, the mean Constant score was 94.8 (range: 84-100) showing a significant increase compared with the mean pre-operative value of 34.4 (range: 25-52) (p0.001). The mean DASH score was significantly decreased from 19.6 (range: 14-28) preoperatively to 0.25 (range: 0-3) at the last follow-up (p0.001). The mean VAS score showed a significant decrease from 5.75 (range: 4-7) to 0.2 (range: 0-2) (p0.001). The mean CC distance on the operated shoulder was found to have no significant difference from the CC distance on the contralateral normal side (10.5 vs. 10mm) (p0.05). There was no evidence of AC joint osteoarthrosis, CC calcification or osteolysis of the distal clavicle or the coracoid process.The proposed mini-open technique provides adequate exposure of the base of the coracoid with minimal damage to the soft tissues surrounding the CC ligaments while ensures an excellent cosmetic result. We recommend this fast and relatively simple technique for all type IV injuries and for type III injuries in heavy manual workers and high-demand upper extremities athletes.

Purpose To examine the afferent pathways of the scapholunate interosseous ligament (SLIL)–generated stimuli and their contribution to the overall carpal proprioception. Methods We examined 5 selected patients with preganglionic global root avulsion, confirmed by previous brachial plexus exploration, during the initial stage of carpal arthrodesis surgery. Despite their anesthetic-flail extremity, both the distal axon and the ganglionic cell were intact and able to transfer afferent stimuli. We placed electrodes subcutaneously over the adjacent areas of the ulnar, median, and radial nerves at the elbow region and performed an intraoperative neurophysiologic study. We studied the homologous sensory action potentials (SAPs) generated at the wrist in relaxation, flexion, extension, radial deviation, and ulnar deviation positions at each nerve and repeated them in 2 stages. The first took place with the SLIL intact and the second with the SLIL lacerated. The noise from the rest of the wrist elements was digitally eliminated. Results After the SLIL laceration, SAP intensities recorded at the median nerve in every wrist position were reduced. The radial and ulnar nerves showed differences of lesser degrees between the recorded SAP intensities before and after the ligament sectioning in every carpal position, with only the radial nerve following a specific pattern. The SAP intensity recorded at the median nerve in every carpal motion after the SLIL laceration was similar to the SAP intensity at relaxation with the SLIL intact, whereas recordings of various intensities were present for the radial and ulnar nerves. Conclusions The SLIL generates proprioceptive stimuli at every wrist position. The main innervation of the whole SLIL derives from the anterior interosseous nerve; a partial contribution of the posterior interosseous nerve focused on the dorsal subregion of the ligament may also be present.

Only 18 cases of congenital radial pseudarthrosis have been reported in the English literature; of these, 4 have been treated with free vascularized fibular graft. We present a case of a 9-year-old female patient with neurofibromatosis type 1 who underwent gradual distraction through the pseudarthrosis site and subsequent vascularized fibular grafting for isolated congenital pseudarthrosis of her left radius and concomitant longitudinal and angular deformity of the wrist joint. At the last follow-up, 10 years postoperatively, the patient has maintained bony union, with full wrist flexion-extension and forearm pronation-supination.

Summary An entire generation of orthopaedic and plastic surgeons has been indelibly and perhaps overwhelmingly influenced by the introduction of microvascular technology to the fields of limb salvage and musculoskeletal reconstruction. Free-tissue transfer using microsurgical techniques has become a valuable method for the salvage of lower extremities after trauma. The goals of free flaps are both soft-tissue coverage and improvement of the functional outcome. The flap selection criteria for lower extremity reconstruction are based on the wound surface area, the type of tissue deficiency, length of the pedicle, volume of deficient tissue components and donor site morbidity. Composite flaps represent the state-of-the-art for reconstructive microsurgery, providing more than one function. Although many different treatment protocols have been proposed, they all highlight the importance of early tissue coverage with bone management performed in a later stage.

The aim of the present study is to evaluate the effects of erythropoietin to the collateral sprouting by using systemically delivered erythropoietin in an end-to-side nerve repair model. Forty-five rats were evaluated in four groups: (A) end-to-side neurorrhaphy only, (B) end-to-side neurorrhaphy and erythropoietin administration, (C) end-to-end neurorrhaphy and (D) nerve stumps buried into neighboring muscles. In all animals, the contralateral healthy side served as control. Functional assessment of nerve regeneration was performed at intervals up to 5 months using the Peroneal Function Index. Evaluation 150 days after surgery included peroneal and tibial nerve morphometric examination, and wet weights of the tibialis anterior muscle. During the first three weeks after surgery, when erythropoietin was regularly administered, functional evaluation showed that erythropoietin may facilitate peripheral nerve regeneration. However, there was rapid deterioration in the functional recovery when erythropoietin's administration was discontinued. As a consequence, at the end of this study, erythropoietin failed to maintain its initial stimulating effect in axonal regeneration. The results of wet muscle weights revealed statistically significant differences between Groups A and C, and Group B. Furthermore, data on axonal counting showed significant difference between Groups A and C, and Group B. Erythropoietin appears to facilitate peripheral nerve regeneration at the initial phase of its administration. Further investigation will be necessary to optimise the conditions (dose, mode of administration) in order to maintain its effects.

Femoral neck fractures, frequently complicated by non-union and femoral head osteonecrosis,present a difficult clinical situation, especially when young patients are concerned. Existing treatment options are valgus osteotomy to address the biomechanical factors or bone grafting to address the biologic factor. The authors describe the operative technique and results of combined subtrochanteric valgus osteotomy and free vascularized fibular grafting in management of five young patients with both non-union and avascular necrosis.

Efficiencies of a nuclease resistant antisense oligonucleotide and of siRNA both being targeted against the green fluorescent protein stably expressed in HeLa cells are compared in cell cultures and in xenografted mice. Using Cytofectin GSV to deliver both inhibitors, the siRNAs appear to be quantitatively more efficient and its effect is lasting for a longer time in cell culture. In mice, we observed an activity of siRNAs but not of antisense oligonucleotides. The absence of efficiency of antisense oligonucleotides is probably due to their lower resistance to nuclease degradation.

Yttrium aluminum iron garnet Y 3 Fe 5− x Al x O 12 compounds were produced by the citrate gel process by varying the aluminum content x from 0 to 2. Particles with an average size of about 100 nm and a specific surface area ranging from 6 to 28 m 2 /g were obtained. Curie temperatures ( T C ) were determined from the temperature dependence of the field-cooled magnetization (FCM) and the remnant magnetization (REM) and range from –40°C to 280°C. According to the magnetic moment variation, the aluminum cation seems to replace the iron cation in the tetrahedral site for compounds with x

We developed a microtitre hybridization assay for the detection of polymerase chain reaction (PCR) amplified sequences. For this, cloned Mycoplasma pneumoniae DNA containing a sequence complementary to the PCR products is first covalently bound to microtitre wells. These coated microplates can be stored for several months. Then, an aliquot of the PCR product, labelled with digoxigenin-dUTP during its synthesis is hybridized to the immobilized DNA. The use of a rapid hybridization buffer makes this step very short (5 min). Finally, the hybridization signal is detected by an anti-digoxigenin antibody conjugated with alkaline phosphatase. Compared to Southern or other microplate hybridization techniques, this method is cheaper, involved fewer steps and allows easy handling of a large number of samples. This method was used for detection of M. pneumoniae in a series of clinical specimens.

Tin(II) fluoride reacts with Lewis acids, AsF 5 and SbF 5 , in a 2:1 ratio, to give salts of the [Sn 2 F 3 + ] cation. Reaction of SnF·MF 6 with SnF 2 in liquid SO 2 also produces the [Sn 2 F 3 ] [MF 6 ] salt. Tin-119 Mossbauer data are presented and compared with those for SnF 2 , SnF·MF 6 and Sn(SbF 6 ) 2 .