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B Battiston

Publications and source records attributed to B Battiston.

At least 19 recordsLinked to original sources

Comparison of fresh and predegenerated muscle-vein-combined guides for the repair of rat median nerve.

Over the last 10 years, we have investigated a particular type of bioengineered nerve guide, the muscle-vein-combined tube, which is made by filling a vein with skeletal muscle. In our previous studies we have always used fresh skeletal muscle to fill vein conduits. In the present study we compared the use of fresh and predegenerated (freeze-thawed) skeletal muscle for muscle-vein-combined nerve guides. In this study, a 10-mm-long rat median nerve defect was repaired using either type of nerve guide. The samples were analyzed 5 and 30 days after surgery by light and electron microscopy. In addition, reverse transcription polymerase chain reaction (RT-PCR) was carried out to investigate the expression of mRNAs coding for glial markers, as well as glial growth factor (NRG1) and its receptors (erbB2 and erbB3). Results showed differences between the two types of nerve guides at postoperative day 5; however, no difference was detected at day 30 suggesting that both types of tissue-engineered conduit are effective for repairing peripheral nerve defects in this experimental model.

Animals↗

Low-power laser biostimulation enhances nerve repair after end-to-side neurorrhaphy: a double-blind randomized study in the rat median nerve model.

Previous studies have shown that low-power laser biostimulation (lasertherapy) promotes posttraumatic nerve regeneration. The objective of the present study was to investigate the effects of postoperative lasertherapy on nerve regeneration after end-to-side neurorrhaphy, an innovative technique for peripheral nerve repair. After complete transection, the left median nerve was repaired by end-to-side neurorrhaphy on the ulnar "donor" nerve. The animals were then divided into four groups: one placebo group, and three laser-treated groups that received lasertherapy three times a week for 3 weeks starting from postoperative day 1. Three different types of laser emission were used: continuous (808 nm), pulsed (905 nm), and a combination of the two. Functional testing was carried out every 2 weeks after surgery by means of the grasping test. At the time of withdrawal 16 weeks postoperatively, muscle mass recovery was assessed by weighing the muscles innervated by the median nerve. Finally, the repaired nerves were withdrawn, embedded in resin and analyzed by light and electron microscopy. Results showed that laser biostimulation induces: (1) a statistically significant faster recovery of the lesioned function; (2) a statistically significant faster recovery of muscle mass; (3) a statistically significant faster myelination of the regenerated nerve fibers. From comparison of the three different types of laser emissions, it turned out that the best functional outcome was obtained by means of pulsed-continuous-combined laser biostimulation. Taken together, the results of the present study confirm previous experimental data on the effectiveness of lasertherapy for the promotion of peripheral nerve regeneration and suggest that early postoperative lasertherapy should be considered as a very promising physiotherapeutic tool for rehabilitation after end-to-side neurorrhaphy.

Animals↗

Schwann-cell proliferation in muscle-vein combined conduits for bridging rat sciatic nerve defects.

Among the various grafting procedures that have been studied as alternatives to traditional fresh nerve autografts for the repair of severed peripheral nerves, muscle-vein-combined graft conduits have recently been devised and successfully employed. In the present study, the early presence, origin, and proliferation activity of Schwann cells (SCs) along this particular type of biological graft conduit have been investigated, using antibodies directed against glial fibrillar acid protein (GFAP), a protein that is specifically expressed in glial cells, and proliferating cell nuclear antigen (PCNA), a protein that is expressed by cells during DNA synthesis. Results showed that the muscle-vein-combined graft was progressively invaded by a number of GFAP-immunopositive SCs, many of which were also found to be immunopositive for PCNA, thus demonstrating that their proliferation continues to occur inside the graft. Among the molecules that could be involved in the stimulation of Schwann-cell proliferation is neuregulin-1 (NRG-1) that mediates its effects by binding to the ErbB receptor tyrosine kinase family. In the present study, the authors report on the RT-PCR analysis for NRG-1 and ErbB3 mRNAs, showing an overall increase in the content of these transcripts inside the muscle-vein-combined graft. These results suggest that the muscle-vein-combined graft conduit constitutes an environment favorable to potentiate Schwann-cell proliferation during the early regeneration phases.

Animals↗

Management of neuromas in continuity of the median nerve with the pronator quadratus muscle flap.

Treatment of painful neuromas in continuity of the median nerve at the wrist level is a challenging problem. Nine median nerve neuromas were covered with the pronator quadratus muscle preelevated as an island flap. Patients were followed for 10 to 60 months after surgery. Results showed a marked improvement in terms of symptoms in all patients. In particular, 6 patients had complete pain relief and 3 patients complained of mild intermittent pain.

Adult↗

Confocal imaging of Schwann-cell migration along muscle-vein combined grafts used to bridge nerve defects in the rat.

Schwann cells guide axonal regrowth during peripheral nerve repair. In a case of a nerve lesion with substance loss, a graft conduit is necessary to enable axons to reach the distal nerve stump. If a non-nervous autograft is used, the question arises as to the presence and origin of Schwann cells along the grafted tube. We addressed this issue using a tubulization technique based on the use of an autologous vein filled with fresh skeletal muscle for the repair of sciatic nerve defects in the rat. We showed that both ends of the graft were early and progressively colonized by a number of glial fibrillar acid protein-immunopositive and S-100 immunonegative cells, an immunocytochemical pattern typical of immature Schwann cells. These cells, which were located in the interstice between grafted skeletal muscle fibers, are mainly organized into long chains oriented along the main axis of the graft and progressively colonize all the graft. Schwann cells coming from the distal nerve end are suitable for being responsible for guiding regeneration of nerve fibers along the graft toward the correct periphery (tissue specificity).

Animals↗

Methodological issues in size estimation of myelinated nerve fibers in peripheral nerves.

Size estimation of myelinated nerve fibers in peripheral nerves is a very common task in neuromorphology and different dedicated morpho-quantitative procedures have been devised and used to date. Unfortunately, many reports on experimental nerve studies lack comprehensive information on the procedures that have been designed and applied for myelinated fiber size estimation. This paper addresses the issue in the light of the recent advances in quantitative morphology that have recognized the concept of unbiased estimates as the key methodological issue to be addressed in morpho-quantitative studies. The potential foundations of bias at various study levels are analysed together with indications on how to cope with them. In addition, the issue of the precision of size estimates is addressed and the various geometrical parameters that can be selected for myelinated nerve fiber size assessment are outlined. Taken together, information provided in this paper is expected to help investigators conduct an appropriate preliminary study design phase, the key step for setting up the most adequate morpho-quantitative procedure for any given research goal.

Animals↗

Nerve repair by means of vein filled with muscle grafts I. Clinical results.

Peripheral nerve lesions with a long segment defect need a grafting conduit to heal. Although autogenous nerve grafting is still considered the best method for bridging nerve defects, several alternative types of conduits (biological and synthetic) have been studied. We have demonstrated in previous experimental research in rats that a graft made using a vein (providing a guide for nerve regeneration) filled with fresh skeletal muscle (to prevent vein collapse and support axon regeneration) gave similar results to traditional nerve grafts. On this basis, we decided to use the muscle-vein-combined grafts in clinical cases. From 1993 to 1997, this technique was applied for bridging both sensory and mixed nerve defects (21 cases). We report good results in 85% of our cases with a minimum follow-up of 14 months. These results, obtained on nerve defects ranging from 0.5 to 6 cm in length, seem to be superior to those reported with other kinds of artificial or biological conduits.

Adolescent↗

Nerve repair by means of vein filled with muscle grafts. II. Morphological analysis of regeneration.

The morphological features of regeneration in long-distance (3 cm) muscle-vein-combined grafts were experimentally investigated in the rat sciatic nerve by means of light and electron microscopy. In the early phases of regeneration (14 days after surgery), many regenerating nerve fibers were detected along the muscle-vein-combined graft. Six months after surgery, quantitative morphometrical analysis of myelinated nerve fibers showed that both the total number and density of myelinated nerve fibers were significantly greater in regenerated nerves than in control nerves. The contrary appeared true for the mean fiber size, with fiber size significantly smaller in regenerated nerves. Ultrastructural observations allowed the description of some peculiar aspects of the relationship between muscle fibers, nerve fibers, and Schwann cells in both early and late phases of regeneration.

Animals↗

Tissue specificity in rat peripheral nerve regeneration through combined skeletal muscle and vein conduit grafts.

Diffusible factors from the distal stumps of transected peripheral nerves exert a neurotropic effect on regenerating nerves in vivo (specificity). This morphological study was designed to investigate the existence of tissue specificity in peripheral nerve fiber regeneration through a graft of vein filled with fresh skeletal muscle. This tubulization technique demonstrated experimental and clinical results similar to those obtained with traditional autologous nerve grafts. Specifically, we used Y-shaped grafts to assess the orientation pattern of regenerating axons in the distal stump tissue. Animal models were divided into four experimental groups. The proximal part of the Y-shaped conduit was sutured to a severed tibial nerve in all experiments. The two distal stumps were sutured to different targets: group A to two intact nerves (tibial and peroneal), group B to an intact nerve and an unvascularized tendon, group C to an intact nerve and a vascularized tendon, and group D to a nerve graft and an unvascularized tendon. Morphological evaluation by light and electron microscopy was conducted in the distal forks of the Y-shaped tube. Data showed that almost all regenerating nerve fibers spontaneously oriented towards the nerve tissue (attached or not to the peripheral innervation field), showing a good morphological pattern of regeneration in both the early and late phases of regeneration. When the distal choice was represented by a tendon (vascularized or not), very few nerve fibers were detected in the corresponding distal fork of the Y-shaped graft. These results show that, using the muscle-vein-combined grafting technique, regenerating axons are able to correctly grow and orientate within the basement membranes of the graft guided by the neurotropic lure of the distal nerve stump.

Animals↗

Morphological analysis of peripheral nerve regenerated by means of vein grafts filled with fresh skeletal muscle.

Clinical data have shown that a vein segment filled with fresh skeletal muscle can be considered a good autologous grafting conduit for the repair of peripheral nerve lesions. In this study, the long-term morphological organization of rat sciatic nerve fibers regenerated along a muscle-vein-combined graft conduit is further analysed by light and electron microscopy. Regenerated nerve fibers were organized into fascicles of various sizes that were clearly delimited by perineurial-like shells made by long and thin cytoplasmic processes of perineurial-like bipolar cells and by densely packed collagen fibrils. Grafted skeletal muscle fibers were still detectable among nerve fiber fascicles. However, in spite of the persistence of skeletal muscle along the graft, regenerated nerve fibers showed a good morphological pattern of regeneration, providing further evidence that the muscle-vein-combined grafting technique represents an effective surgical alternative to the classical fresh nerve autograft for the repair of peripheral nerve defects.

Animals↗

Verification of the two-dimensional disector, a method for the unbiased estimation of density and number of myelinated nerve fibers in peripheral nerves.

Quantification of the number of myelinated fibers in peripheral nerves is a common requirement in quantitative morphology. This parameter provides important information on the consequences of various physiological, pathological and experimental conditions on the nerve structure and is one of the main indicators of success of peripheral nerve repair. In this paper, the theoretical rationale for the application of stereological principles to obtain unbiased estimates of the density and total number of myelinated fibers in peripheral nerves is discussed and a simple stereological method is described. The method is applied together with a systematic random sampling scheme, that was optimized for the purposes of the present study, and with sampling scheme analysis by calculating the coefficient of error (CE). The stereological method, which consists of a two-dimensional variation of the classical disector procedure (two-dimensional disector), and the sampling scheme are verified by comparing estimates with the true density and total number of myelinated fibers in peripheral nerve trunks where true values have been accurately determined by extensive counting. The verification of the 2-D disector method, both of normal and regenerated nerves, showed that estimates of density and total number of myelinated nerve fibers are unbiased. The method also proved to be efficient (time-saving): Estimation of density and total number of myelinated fibers in a single nerve takes about 2-3 hours.

Animals↗

Reconstruction of high ulnar nerve lesions by distal double median to ulnar nerve transfer.

Ulnar nerve lesions around the elbow often carry an unfavorable prognosis due to insufficient sensory and intrinsic muscle recovery. We present a series of 7 cases in which restoration of ulnar innervated intrinsic muscles of the hand and of skin sensibility was achieved. This was accomplished by a distal connection of the anterior interosseous nerve and the superficial sensory palmar branch of the median nerve to the motor and sensory components of the ulnar nerve at Guyon's canal. The length of the follow-up period ranged from 1 to 3.5 years. Results were graded by the Highet-Zachary scale. Good motor and sensory recovery was obtained in 6 cases; only return of protective sensation occurred in the remaining case.

Adult↗

Assessment of vascularized fibular graft one year after reconstruction of the wrist after excision of a giant-cell tumour.

We report a patient in whom the distal radius was resected for a giant cell tumour and the bone defect was replaced using a vascularized proximal fibular graft. The graft was viable and hypertrophied and normal callus formed on the distal radius. Due to chronic instability of the wrist the patient underwent revision arthrodesis 1 year after resection. Microscopic studies of the epishyseal region of the fibula showed wide necrosis of the graft with active creeping substitution. Despite the good technical result of the vascularized fibular graft, the vascularization was incomplete in the proximal epiphysis. We discuss possible reasons for this.

Arthrodesis↗

The role of allopurinol in preventing oxygen free radical injury to skeletal muscle and endothelial cells after ischemia-reperfusion.

One of the most important mechanisms in the production of ischemic damage after replantation surgery is the rise of oxygen free radicals during revascularization of ischemic tissues. Free radicals produce damage in the cell membranes (lipoperoxydation). This occurs not only in muscle tissue, but also in endothelial cells, with a consequent increase of local edema and the risk of compartment syndrome. This study attempted to interrupt the ischemic-reperfusion injury process in ischemic rat hindlimbs. Complete ischemia was induced for different numbers of hours (3, 6, 9, 12 hr) in four groups of rats (24 animals in each group). Allopurinol, an oxygen free radical scavenger, was tested in solution, 12.5 mg/kg b.w., in half the studied animals (n = 12). Collected data showed an increase (mean value: 0.60 nM/mg 3 hri 0.90 nM/mg at 6 hr; 0.80 nM/mg at 9 hr; 0.89 nM/mg at 12 hr; mean value in nonischemic muscle = 0.526 nM/mg) in lipoperoxides (NS between treated/untreated groups, p > 0.05) and high tissue pressure values in the posterior compartment of the ischemic rat hindlimbs. Allopurinol reduced the pressure values (p < 0.05 in Groups 1-3; p < 0.1 in Group 4), but was not effective in reducing lipoperoxides in skeletal muscle.

Allopurinol↗

Coracoacromial ligament: a comparative arthroscopic and anatomic study.

An anatomic study of the coracoacromial ligament was conducted. The data collected from 20 anatomical preparations and the arthroscopic findings in 40 cases were compared. The shape and the tension of the ligament were evaluated, as well as the thickness. Anatomic tradition describes the ligament as a fibrous triangular lamina inserted with its apex on the acromial tip and its base on the lateral edge of the coracoid. It simply closes the coracoacromial arch and has no mechanical role. However, our observations suggest that the ligament has a trapezoidal shape and is situated below the acromion with a wide reflex portion. Its thickness varies from 2 to 5.6 mm. Given that structure, the ligament appears like a robust suspension structure of the coracoid, which contrasts the action of the muscles that connect to it. From these observations, a pathogenic hypothesis of the subacromial impingement proposes itself.

Acromion↗

Bridging nerve defects with combined skeletal muscle and vein conduits.

The use of vein or muscle grafts to bridge nerve defects longer than 1-1.5 cm gives poor results. Veins collapse and in muscle grafts axons may regrow outside the graft. We used veins (to guide regeneration) filled with muscle (to avoid vein collapse). Nerve regeneration through 1 and 2 cm grafts made of vein plus muscle was compared with similarly long traditional nerve grafts, free fresh muscle grafts, and empty vein grafts. Regeneration was assessed clinically and histologically (qualitative and quantitative evaluation) in the graft and distal nerve stumps. Vein plus muscle grafts were superior to vein and fresh muscle grafts both functionally and histologically. Functional results were similar to those found in traditional nerve grafts, but axon number was superior in the veins filled with muscle. This suggests that vein filled with muscle might serve as a grafting conduit for the repair of peripheral nerve injuries and could give better results than traditional nerve grafting.

Animals↗

Gnostic rings: usefulness in sensibility evaluation and sensory reeducation.

The benefit of additional clinical tools for quantifying patients' ability to recognize objects is clear, as well as its correlation with the moving two-point discrimination test. The recognition of letters is such a tool. The authors describe gnostic rings, an additional technique, that is useful for clinical sensibility testing, as well as for sensory reeducation.

Discrimination, Psychological↗

The effects of lengthening on nerves.

Use of external fixators in limb lengthening and skin expanders in plastic surgery are well-known operative techniques. In some cases neurologic complications arise due to distraction which is either excessive or too fast. What happens to the nerve in these cases has not yet been thoroughly investigated. We therefore conducted an experiment on the sciatic nerve of rats. In one group of animals the nerve was studied after lengthening the femur, and in the other group after lengthening the nerve itself with a skin expander. Electrophysiologic and histologic studies (optic microscopy and axon teasing) were used to examine the effects of tension on the sciatic nerve. The results suggest that if distraction is performed gradually, the nerve does not undergo any electrophysiologic functional changes. It does, however, undergo some morphologic changes, such as a decrease in both the areas of the axons and the myelin sheaths, an increase in the distances between the nodes, and proliferation of Schwann cells.

Animals↗