Reconstruction of metatarsal bone after giant cell tumor resection with no vascularized fibular graft in a pediatric patient: Case report and review of literature.

The Giant Cell tumor (GCT) is a benign, locally aggressive lesion that cause bone destruction and shows a malignant potential. It is a relatively common skeletal tumor that is therefore typically seen in young adults. Few cases are described in literature of GCT in the immature skeleton, and the metatarsal is an unusual location for a primary bone GCT, especially in pediatric age. Therefore, there are very few data reported regarding the management protocol of GCT in metatarsal bones. We report a case about the use of no vascularized fibular graft for an original Y-shaped reconstruction of the metatarsal bone after Giant Cell Tumor resection in a 9 years-old patient, and performed a literature review about metatarsal bone reconstruction in skeletally immature patient.

Managing of musculoskeletal infections in children.

OBJECTIVE: Epidemiological features of musculoskeletal infections are in continuous evolution. The incidence of emerging causative pathogen is arising. Nevertheless, up to 50% of osteoarticular infections shows negative cultures. Septic arthritis, with or without concurrent osteomyelitis, are most common in newborn while osteomyelitis frequently affects older patients. We retrospectively analyzed all the children affected by musculoskeletal infections treated at the Children's Hospital Bambino Gesù in ten years, focusing on the results of an early diagnostic and therapeutic management. MATERIALS AND METHODS: The study population consists of 150 children with acute septic arthritis, osteomyelitis and discitis, treated from 2006 to 2016, excluding patients with less than 12 months of follow-up and previous treatment sustained in others hospitals. A wide spectrum of data has been extracted from clinical charts, laboratory studies and imaging. Patients were categorized into 3 groups on the base of their age. The diagnostic and therapeutic protocol consisted of intravenous empirical treatment while diagnosis was ongoing then switched to oral treatment, according to the pathogen and the systemic symptoms. RESULTS: Only 31% of pathogens were identified. The most common was Staphylococcus aureus methicillin-sensible (MSSA) but an increase of cases caused by Kingella Kingae and Staphylococcus aureus methicillin-resistant (MRSA) was observed. The mean antibiotic treatment was 6.8 weeks. It's important to underline a significant correlation between age and C-reactive protein serum levels. CONCLUSIONS: Among others frequent pathogens, MRSA shows a high rate of physis involvement. Musculoskeletal infections represent a challenge in skeletally immature patients because of their potential severe complications. Timing of diagnosis and consequent targeted treatment is fundamental to avoid complications and functional sequelae.

Single-step microwave digestion of food and biological samples for the quantitative conversion of Se into the +4 oxidation state.

An improved single step microwave digestion procedure is described for providing the fast and easy exhaustive mineralisation of biological samples concomitantly with the quantitative conversion of any type of selenium compounds into Se(IV). In such a way, digested samples are directly suitable for the subsequent Se analysis at trace and ultratrace levels by both spectrometric methods such as HG-ICP-MS or HG-ICP-OES and differential pulse cathodic stripping voltammetry (DPCSV). It is based on the use, under suitably optimised microwave irradiation conditions, of a digestion mixture with a carefully tailored composition such that its redox potential is made lower than that allowing Se(IV) to be oxidized to Se(VI), but high enough to permit total destruction of biological or, in general, organic matrices. It consists of a nitric acid (65%, w/w) and hydrogen peroxide (30%, w/w) mixture in a volume ratio 5:1, frequently adopted for the mineralisation of organic and biological samples, but added simply with 0.25 g mL(-1) of NaCl. Successful application of the procedure, in terms of both repeatability and accuracy, to the quantification of selenium by the instrumental methods above in standard compounds and in a certified biological sample proved its good performance. The application to the Se determination in human blood plasma and in a wide variety of foods is also reported.

An electroanalytical investigation on the redox properties of lacidipine supporting its anti-oxidant effect.

The redox properties of lacidipine (PyH2), one of the most pharmacologically active N-unsubstituted 1,4-dihydropyridines, have been studied by cyclic voltammetry and controlled potential electrolysis in acetonitrile, an aprotic solvent that is, at best, a mimic of the lipofilic layer of biological membranes. PyH2 undergoes a two-electron oxidation process involving two consecutive one-electron releases, the latter requiring potentials much less positive than the former. The overall process occurs through a primary one-electron step accompanied by a fast proton release, with the formation of a neutral radical (PyH*), which undergoes a further and quite easier one-electron step, thus providing the main ultimate product (PyH+) consisting in the protonated form of the parent pyridine derivative. This appears relevant for the anti-oxidant effect since the radical intermediate is much more prone to be oxidized than to be reduced, thus preventing the propagation of the oxidative chain reaction. The mentioned release of protons in the primary electrode step causes the overall process to be complicated by a parassite side reaction involving the coupling between one of the electrode products (H+) and the starting species. The protonation of PyH2 subtracts part of the original species from the electrode process because the parent cationic species (PyH3+) is no longer electroactive. This parassite reaction occurs rather slowly in the timescale of electroanalytical measurements (the relevant kinetic constant has been estimated to be 6.4 l mol(-1) s(-1)), thus markedly affecting the process only in the presence of relatively high PyH2 concentrations and progressively decreasing with the starting PyH2 concentration. All the products formed in the oxidation process (PyH+, H+ and PyH3+) have been identified by voltammetric evidences based on deep investigations on their cathodic behaviour. The advantageous anti-oxidant properties displayed by PyH2 with respect to those exhibited by phenolic anti-oxidants such as vitamin E are also discussed.

Potential shifts at electrodes coated with ion-exchange polymeric films.

Voltammetry at electrodes modified with ion-exchange polymers, named "ion exchange voltammetry", has been recently developed for characterizing and determining quantitatively ionic electroactive analytes preconcentrated at the electrode surface. Like for other voltammetric techniques, characterization is based on the position of the response on the potential scale, but an appreciable difference is frequently observed between the formal half-wave potential for redox couples incorporated within ion-exchange polymeric films and those for the same redox couples in solution as measured at bare electrodes. Such a difference has been rationalized here by a generalized equation, inferred from a suitable elaboration of the Nernst equation, whose validity has been tested by a thorough investigation performed at glassy carbon electrodes modified with either cationic (Nafion) or anionic (Tosflex) polymeric films. With this purpose, the effect of both charge and concentration of the analyte and of the loading counterion, this last introduced as the cation or anion of the supporting electrolyte, of the ion-exchange selectivity coefficients of the redox partners and of their stoichiometric coefficients, as well as of the number of electrons involved in the charge transfer has been evaluated. The results obtained agree quite well with theoretical expectations and indicate that the potential shifts found are mainly conditioned by both charge and concentration of the counterion from the supporting electrolyte and by the ratio of the ion-exchange equilibrium constants for the two redox partners involved. Other parameters considered have no influence on the potential shift or lead to negligible effects, provided that the quantities of the redox partners incorporated within the ion-exchange coating represents less than 5% of the film capacity. Again in agreement with theoretical expectations, positive shifts are found for increasing supporting electrolyte concentrations when cationic redox species incorporated within cationic films are involved, while the opposite effect is found for anionic redox species incorporated within anionic films.

[Considerations on the role of echography in the study of hip dysplasia]. / Considerazioni sul ruolo dell'esame ecografico nello studio della displasia dell'anca.

The authors explain the general criteria in performing an ultrasound exam and the pathological finding of congenital dislocation of the hip. They based the study on the screening of 500 patients between the ages of ten days and eight months (2% of which resulted pathological) and on evaluation of 80 cases of dislocated hip not included in the original sample group. The ultrasound test in dislocated hip pathology proved to be superior to traditional x-ray tests for viewing the muscular and cartilaginous elements, obtaining a dynamic view of the anatomical structures and, in particular, studying the morphological aspect and the development of the acetabulum. Thus it is possible diagnose different types of CDH at very early stage. The authors, however, consider an easier classification more useful than the original one suggested by Graf and propose division of the abnormal hip into three pathological types based on clinical, radiological and ultrasound findings: primary sub-luxation or "non-dislocatable" hip; pre-dislocation or "dislocatable" hip; dislocation or "dislocated" hip. This is extremely important in order to better understand and evaluate each singular case and then set up adequate therapy.

[Rare skeletal pathology: the diagnostic problems in the first year of life]. / Patologia rara dello scheletro: problemi diagnostici nel primo anno di vita.

The authors report a series of affections which determine diffused modifications of the skeleton during early childhood. More common pathological forms are dealt with, of relatively simple diagnosis, and having pathological pictures which based on frequency, means of occurrence, and clinical-radiographic aspects, are rarely observed, and difficult to diagnose. Based on several clinical cases, the authors report problems related to diagnosis, emphasising the meaning of various radiographic pictures and the value and choice of hematochemical tests aimed at selecting patients in whom biopsy is required.

[Torsional changes in the lower limbs in childhood]. / Le alterazioni della torsione degli arti inferiori in età pediatrica.

Based on their observation of approximately 1000 patients aged from 4 to 14 years and on a comparison of their experience with the data reported in the literature, the authors discuss the problem of modifications in torsion of the lower limbs during pediatric age. After a brief discussion of anatomy and the natural progression of the angle of femoral anteversion and tibial torsion, they stop to accurately describe the most frequently occurring defects in torsion, both isolated and combined. After affirming the contribution that axial vision has made to an understanding of the subject, they emphasise the current usefulness of the method in cases in which a clinical examination allows for doubts to persist and, in particular, if qualitative and quantitative diagnosis is required in relation to the therapeutic protocol. The authors conclude by suggesting that therapy be carried out during the growth age (much before 14 years of age) while they suggest waiting until skeletal maturity in order to make a general evaluation and to decide on treatment of combined defects.

[The Freeman-Sheldon syndrome]. / La sindrome di Freeman-Sheldon.

The authors report two cases of Freeman-Sheldon syndrome, characterised by recessive autosomic transmission, affecting a brother and a sister born of parents who were not blood relations. The syndrome, for which 50 cases are described in the literature, takes its name from the authors who were the first to describe it in 1938. The typical picture is based on congenital deformity involving the cranium, the face and the locomotor apparatus, with a particular aspect of the subject affected related to his or her expression, resembling that of someone whistling ("whistling face", Burian, 1963). In addition to the descriptive aspect of the syndrome and to the means of its transmission, the authors report orthopaedic aspects concerning the locomotor apparatus and problems related to the type of surgery performed.