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Background/aim: Quantitative analysis of amoxicillin and clavulanic acid in biological matrices requires sensitive and specific methods which allow determination of therapeutic concentration in 1 g/mL range. Analytical methods for determination of their concentrations in body fluids described in literature include high performance liquid chromatography coupled to UV detector (HPLC-UV) and liquid chromatography-mass spectrometry (LC-MS). The aim of this study was to develop sensitive and specific ultra performance liquid chromatography/mass spectrometry (UPLC/MS) method which could be used for the spectral identification and quantification of the low concentrations of amoxicillin and clavulanic acid in the human plasma., Method: A sensitive and specific UPLC/MS method for amoxicillin and clavulanic acid determination was developed in this study. The samples were taken from the adult healthy volunteers receiving per os one tablet of amoxicillin (875 mg) in combination with clavulanic acid (125 mg)., Results: Plasma samples were pretreated by direct deproteinization with perchloric acid. Quantification limit of 0.01 microg/ml for both amoxicillin and clavulanic acid was achieved. The method was reproducible day by day (RSD < 7%). Analytical recoveries for amoxicillin ranged from 98.82% to 100.9% (for concentrations of 1, 5 and 20 microg/mL), and recoveries for clavulanic acid were 99.89% to 100.1% (for concentrations of 1, 2 and 5 microg/mL). This assay was successfully applied to a pilot pharmacokinetic study in healthy volunteers after a single-oral administration of amoxicillin/clavulanic combination. The determined plasma concentrations of both amoxicillin and clavulanic acid were in the range of the expected values upon the literature data for HPLC-UV and LC-MS methods., Conclusion: The described method provided a few advantages comparing with LC/MS-MS method. The method is faster using running time of 5 minute, has lower limit of quantification (LOQ) and it could be used in pharmacokinetic studies of both amoxicillin and clavulanic acid.

After limb or body part amputation, three different types of perceptual sensitive phenomena can be recognized. They can be all named posttraumatic neuropathies: painless sensations in phantom limb, painful phantom limb and painful posttraumatic stump. Painless sensations in phantom limb can be seen in 90% of cases in resected body parts as soon as first postoperative day, less often during the first week, and its clinical characteristics are usually stabilized during the first year. Painful posttraumatic stump appears because of pain neuroma existing, that forms at the proximal end of amputational stump as a consequence of physiological nerve regeneration attempt. Frequency of pain significantly varies considering authors from 5-90%, depending on definition of this phenomena and criteria used. It is considered that 5-10% mast be under permanent medicament treatment. Phantom pain appears more often in elderly and people with specific affective personality construction. It can be permanent, burning, nettling, tearing (25%), or intermittent, lancerating, in the shape of electrical discharging (32%), but it can also have bizarre attributes. Phantom pain appearance usually announces its duration in the longer period. After two years it is present at 59% of patients, with decreasing intensity, and only 5-10% suffer severe pain. In our Institute in the period from 1980-2003, 48 patients have been treated, 36 patients with medicamentous treatment, local blockades and chronic stimulations, and 12 patients, who did not react at conservative treatment were operated. In operated group in 10 patients pain disappeared, one patient it was with decreasing intensity, and one patient was without change.

Autologous nerve grafting is the most commocommnlynly used operative technique in delayed primary, or secondary nerve repair after the peripheral nerve injuries. The aim of this procedure is to overcome nerve gaps that results from the injury itself, fibrous and elastic retraction forces, resection of the damaged parts of the nerve, position of the articulations and mobilisation of the nerve. In this study we analyse the results of operated patients with transections and lacerations of the peripheral nerves from 1979 to 2000 year. Gunshot injuries have not been analyzed in this study. The majority of the injuries were in the upper extremity (more than 87% of cases). Donor for nerve transplantation had usually been sural nerve, and only occasionally medial cutaneous nerve of the forearm was used. In about 93% of cases we used interfascicular nerve grafting, and cable nerve grafting was performed in the rest of them. Most of the grafts were 1 do 5 cm long (70% of cases). Functional recovery was achieved in more than 86% of cases, which is similar to the results of the other authors. Follow up period was minimum 2 years. We analyzed the influence of different factors on nerve recovery after the operation: patient's age, location and the extent (total or partial) of nerve injury, the length of the nerve graft, type of the nerve, timing of surgery, presence of multiple nerve injuries and associated osseal and soft tissue injuries of the upper and lower extremities.

The facial nerve is main motor nerve of the face and its injury leads to total ipsilateral paralysis. There are several surgical procedures in reconstruction of the facial nerve, and the most frequent one is hypoglosso-facial anastomosis. In this study were analysed a series of 69 patients operated on Institute of neurosurgery from 1981 to 2000 year. The most frequent cause of injury was the operation of cerebellopontine angle tumors, as well as the skull base fractures. Hypoglosso-facial anastomosis was done in 57 patients, in 5 cases we performed nerve grafting in the cerebellopontine angle, and in 7 patients the facial nerve was operated peripherally. Results were analyzed in 27 of 57 patients with hipoglosso-facial nerve anastomosis. Functional recovery was achived in 22 (81.4%) patients.

There have been studied effects of cystaphos, gammaphos, hydroxyurea, polyadenyl-polyuridinic acids (poly A:poly U) as well as the combination of gammaphos and poly A:poly U, that is, cystaphos and superoxide dismutase on the thymus of Wistar and AO rats irradiated by the hard X-rays in the dose of 5 or 3.5 Gy. Changes were observed up to 30 days after irradiation. The most efficacious protective effect has shown cystaphos (358 mg/kg i.p. 20 min. after irradiation) in Wistar rats irradiated by the dose of 3.5 Gy. It lowered involutive changes and accelerated thymus regeneration. On the basis of phenotypic analysis of thymocytes it can be supposed that such a favourable effect is the consequence of a larger protection of the cortical (strong OX 7+) thymocytes. Differing from cystaphos, transplantation of the syngeneic cells of the bone marrow in AO rats irradiated by the dose of 5 Gy showed favourable effect on thymus regeneration in later phase after irradiation preventing secondary thymus involution.