Francesco Meli

Neuroprotection by erythropoietin administration after experimental traumatic brain injury.

A large body of evidence indicates that the hormone erythropoietin (EPO) exerts beneficial effects in the central nervous system (CNS). To date, EPOs effect has been assessed in several experimental models of brain and spinal cord injury. This study was conducted to validate whether treatment with recombinant human EPO (rHuEPO) would limit the extent of injury following experimental TBI. Experimental TBI was induced in rats by a cryogenic injury model. rHuEPO or placebo was injected intraperitoneally immediately after the injury and then every 8 h until 2 or 14 days. Forty-eight hours after injury brain water content, an indicator of brain edema, was measured with the wet-dry method and blood-brain barrier (BBB) breakdown was evaluated by assay of Evans blue extravasation. Furthermore, extent of cerebral damage was assessed. Administration of rHuEPO markedly improved recovery from motor dysfunction compared with placebo group (P<0.05). Brain edema was significantly reduced in the cortex of the EPO-treated group relative to that in the placebo-treated group (80.6+/-0.3% versus 91.8%+/-0.8% respectively, P<0.05). BBB breakdown was significantly lower in EPO-treated group than in the placebo-treated group (66.2+/-18.7 mug/g versus 181.3+/-21 mug/g, respectively, P<0.05). EPO treatment reduced injury volume significantly compared with placebo group (17.4+/-5.4 mm3 versus 37.1+/-5.3 mm3, P<0.05). EPO, administered in its recombinant form, affords significant neuroprotection in experimental TBI model and may hold promise for future clinical applications.

Neuroprotective effect of erythropoietin and darbepoetin alfa after experimental intracerebral hemorrhage.

OBJECTIVEIntracerebral hemorrhage (ICH) is a devastating clinical syndrome for which no truly efficacious therapy has yet been identified. In preclinical studies, erythropoietin (EPO) and its long-lasting analog, darbepoetin alfa, have been demonstrated to be neuroprotective in several models of neuronal insult. The objectives of this study were to analyze whether the systemic administration of recombinant human EPO (rHuEPO) and its long-lasting derivative darbepoetin alfa expedited functional recovery and brain damage in a rat model of ICH. METHODSExperimental ICH was induced in rats by injecting autologous blood into the right striatum under stereotactic guidance. Subsequently, animals underwent placebo treatment, daily injections of rHuEPO, or weekly injections of darbepoetin alfa. Animals were killed 14 days after injury. RESULTSBoth rHuEPO and darbepoetin alfa were effective in reducing neurological impairment after injury, as assessed by the neurological tasks performed. rHuEPO- and darbepoetin alfa–treated animals exhibited a restricted brain injury with nearly normal parenchymal architecture. In contrast, the saline-treated group exhibited extensive cerebral cytoarchitectural disruption and edema. The number of surviving NeuN-positive neurons was significantly higher in the rats treated with rHuEPO and darbepoetin alfa compared with those that received saline (P < 0.05). CONCLUSIONThese results demonstrate that weekly administered darbepoetin alfa confers behavioral and histological neuroprotection after ICH in rats similar to that of daily EPO administration. Administration of EPO and its long-lasting recombinant forms affords significant neuroprotection in an ICH model and may hold promise for future clinical applications.

The treatment of venous leg ulcers - A new therapeutic use of Iloprost

Background:We conducted a study using an intravenous (i.v.) infusion of iloprost in the treatment of venous ulcers to verify whether the association of i.v. iloprost + local therapy + elastic compression has a favorable effect when compared with traditional treatment with local therapy and elastic compression. Study Design:We evaluated the effects of iloprost in 98 consecutive patients with noncomplicated venous ulcers of lower limbs subdivided into 2 groups: the first group (48 patients) received iloprost in saline solution for 3 weeks and the second group (50 patients) received a venous infusion of a saline solution. The patients were examined at baseline time 0 (first visit) and then after 15, 30, 45, 60, 75, 90, 105, 120, 135, and 150 days. Results:In the first group, after 90 days, all the ulcers had healed, whereas in the second group only 50% of ulcers had healed after 105 days. At the end of the study, in the second group only 84.09% of ulcers had healed. The statistical analysis showed a significant difference between the first (iloprost group) and the second group (placebo group). Besides, in the first group the cicatrization of the ulcer happened in a shorter period (27.90% after 60 days; 41.86% after 75 days; and 100% after 100 days) whereas in the second group, at the end of the study, in 15.91% of patients the ulcers had not recovered. Conclusion:Iloprost can significantly reduce healing time for venous leg ulcers through several actions.

Optimal Duration of Treatment in Surgical Patients With Calf Venous Thrombosis Involving One or More Veins

The aim of this study was to evaluate different durations of treatment in patients with calf venous thrombosis (CVT) involving 1 or more deep veins. The authors studied 2 groups of patients with postsurgical CVT diagnosed by echo-color Doppler. The first group consisted of 68 patients with CVT involving a single vein, and the second group consisted of 124 patients with CVT involving 2 or more veins. Immediately after diagnosis, all patients were treated with nadroparin calcium and sodium warfarin. Heparin treatment was withdrawn after 5–6 days of treatment, when the international normalized ratio (INR) was stabilized between 2 and 3. Each group was divided into 2 subgroups receiving anticoagulation treatment for 6 or 12 weeks, respectively. The endpoint was proximal extension of the thrombotic lesion, defined as the extension of the thrombus to the popliteal and/or femoral vein. In patients with single-vessel CVT there was no significant difference between the 2 subgroups, whereas in patients with CVT involving 2 or more vessels, a statistically significant difference was observed, the number of cases showing proximal extension of the thrombus being higher among patients treated for 6 weeks. Twelve weeks of anticoagulation treatment is better than 6 weeks only in patients with postsurgical CVT involving 2 or more veins.

An immunohistochemical study of extracellular matrix proteins laminin, fibronectin and type IV collagen in paediatric glioblastoma multiforme

SummaryAims. In the recent decades many studies have been addressed in the literature to assess specific factors related to glioblastoma multiforme (GBM) invasion. However, few studies have evaluated tumour cell’s interaction with specific extracellular matrix (ECM) components, and, moreover, there is a lack of information regarding the occurrence of these phenomena in paediatric GBM.Methods and results. ECM proteins were evaluated in six cases of paediatric GBM assessing the immunohistochemical expression of laminin, fibronectin, and type IV collagen. We used a semiquantitative scale, ranging from not detected (zero) to marked (3). Laminin expression was minimal in three cases, moderate in one case, marked and generalised in one patient and marked and focal in the last case. Fibronectin expression was minimal in three patients; moderate immunoreactivity was documented in one case. Conversely, one case was classified as marked with generalised distribution and the remaining case as marked with focal immunostaining. Type IV collagen expression was minimal in three cases, moderate in one, marked with focal reaction in one and marked with generalised reaction in the remaining case.Conclusions. This study provides additional insights into tumour invasion features of paediatric GBM, as ECM plays a pivotal role in numerous cellular functions during normal and pathological processes. Although based on a limited number of patients, this investigation may serve as a challenge for the management of paediatric GBM, stimulating trials with larger patient numbers aimed at documenting specific factors influencing GBM prognosis.

Growing skull fracture of the posterior cranial fossa and of the orbital roof

Summary. Background: Growing Skull Fractures (GSF) are rare complications of head trauma, primarily reported in infancy and early childhood. GSF are commonly located on calvaria, and rarely in other locations, including the skull base. Method: In this study, we report two cases of GSF occurring in unusual locations. The first, a 8-month old girl, with a GSF of the suboccipital posterior fossa region, and the second, a 4-year old boy with a GSF of the right orbital roof. Both cases underwent operative treatment of the GSF, with microsurgical dissection and excision of the protruding gliotic brain tissue, watertight duraplasty and autologous bone cranial repair. The authors conducted a Medline search of the relevant English literature from 1966 to 2002. Findings: From the search, three cases of suboccipital posterior fossa region GSF and twelve series of orbital GSF, describing a total of 22 cases, have been found. Interpretation: A survey of the pathogenic mechanisms underling this entity in these locations is reported. A review of suboccipital posterior fossa and orbital roof GSF cases, of nosological, ophthalmological and neurological data, neuroradiological and operative findings, and results of different treatment strategies are described.

Residual vein thrombosis and onset of post-thrombotic syndrome: Influence of the 4G/5G polymorphism of plasminogen activator inhibitor-1 gene

BACKGROUND Plasminogen activator inhibitor-1 (PAI-1) is the most important inhibitor of plasminogen activator. The functional 4G/5G polymorphism of the gene coding for PAI-1 may affect PAI-1 plasmatic activity, influencing the imbalance between coagulation and fibrinolysis cascades. In this prospective cohort analytic study, we investigated the role of this single nucleotide polymorphism in the persistence of thrombotic lesion and the occurrence of post-thrombotic syndrome. PATIENTS/METHODS In a group of 168 patients with post-surgical deep vein thrombosis of the legs, we analyzed the 4G/5G polymorphism in the promoter of PAI-1 gene and plasmatic PAI-1 activity. Enrolled patients were divided in two groups: patients with 4G/5G polymorphism and increased PAI-1 activity (n=85) and patients without 4G/5G polymorphism and normal PAI-1 activity (n=83). All patients were treated according to current protocols and re-examined after 3, 12 and 36 months in order to evaluate the persistence of thrombotic lesion and the occurrence of post-thrombotic syndrome. RESULTS We found a significantly increased PAI activity in carrier of the 4G allele, who experienced much more frequently a persistence of thrombosis after 3, 12 and 36 months and/or the development of post-thrombosis syndrome, in spite of the anticoagulant treatment. CONCLUSIONS These data not only confirm the role played by PAI-1 activity and by the 4G/5G SNP of the PAI-1 gene, but also suggest that current therapeutic protocols, recommending the administration of low weight molecular heparin and oral anticoagulant for the treatment of deep vein thrombosis, could be non sufficient for patients genetically predisposed to a less efficient clot lysis.

CD68 and CR3/43 immunohistochemical expression in secretory meningiomas.

OBJECTIVE: Secretory meningiomas (SMs) are unusual benign meningiomas. SMs are highly vascularized lesions, with angiomatous features and a perivascular arrangement, and they are accompanied frequently by massive peritumoral edema. Microglia have been called the brain’s immune system, although the specific role and prognostic significance of microglia remain uncertain. The objective of this study was to analyze the expression of CD68, a macrophage marker specific for resting microglia, and the expression of major histocompatibility complex Class II CR3/43 in SMs. METHODS: From 1995 to 2002, six patients with SMs were treated surgically at our institution. Immunohistochemistry was used to analyze the expression of CD68 and CR3/43 in tumor specimens. The intensity of expression was graded semiquantitatively. A correlation between immunohistochemical expression and the occurrence of brain edema was studied. RESULTS: CD68-positive mononuclear cells were observed in neoplastic tissue or around pseudopsammoma bodies and in perivascular areas, with minimal expression in one patient and moderate expression in three patients. CR3/43-positive complexes were detected in mononuclear elongated elements with ameboid extensions, presumably referable to cells at different stages of immunological activation phenomena, with minimal expression in two patients, moderate expression in one patient, and marked expression in one patient. Edema was severe in all patients. Therefore, it may be indirectly hypothesized that edema may not be correlated with the CD68 and CR3/43 immunohistochemical expression. CONCLUSION: Macrophage infiltration and major histocompatibility complex Class II immunoreactivity in this subtype of meningioma suggest the occurrence of an immune response in the presence of SM.

Immunohistochemical study of the extracellular matrix proteins laminin, fibronectin and type IV collagen in secretory meningiomas

The extracellular matrix plays a pivotal role in numerous cellular functions during normal and pathological processes. Secretory meningiomas are rare histological meningioma subtypes that have benign behavior, are highly vascularized and are frequently accompanied by massive peritumoral edema. The aim of this study was to assess in secretory meningiomas the immunohistochemical expression of laminin, fibronectin and type IV collagen, proteins found in the extracellular matrix. Extracellular matrix proteins were evaluated in samples from six secretory meningiomas using a semiquantitative scale ranging from not detected (0) to marked (3). Laminin expression was not detected in two cases, but was minimal in one, moderate in one and marked in the remaining cases. Fibronectin expression was absent in two cases, minimal in two, moderate in one and marked with generalized distribution in the remaining case. Type IV collagen expression was minimal in three cases, moderate in two and marked with generalized distribution in the remaining case. Our results are indicative of significant neoangiogenic activity. Meningiomas increase in size through increased production of extracellular matrix; furthermore, the proliferation of cells typically associated with neoplasia requires considerable interaction with the extracellular matrix.

With a Little Help from My Friends: The Role of Intraoperative Fluorescent Dyes in the Surgical Management of High-Grade Gliomas

High-grade gliomas (HGGs) are the most frequent primary malignant brain tumors in adults, which lead to death within two years of diagnosis. Maximal safe resection of malignant gliomas as the first step of multimodal therapy is an accepted goal in malignant glioma surgery. Gross total resection has an important role in improving overall survival (OS) and progression-free survival (PFS), but identification of tumor borders is particularly difficult in HGGS. For this reason, imaging adjuncts, such as 5-aminolevulinic acid (5-ALA) or fluorescein sodium (FS) have been proposed as superior strategies for better defining the limits of surgical resection for HGG. 5-aminolevulinic acid (5-ALA) is implicated as precursor in the synthetic pathway of heme group. Protoporphyrin IX (PpIX) is an intermediate compound of heme metabolism, which produces fluorescence when excited by appropriate light wavelength. Malignant glioma cells have the capacity to selectively synthesize or accumulate 5-ALA-derived porphyrins after exogenous administration of 5-ALA. Fluorescein sodium (FS), on the other hand, is a fluorescent substance that is not specific to tumor cells but actually it is a marker for compromised blood-brain barrier (BBB) areas. Its effectiveness is confirmed by multicenter phase-II trial (FLUOGLIO) but lack of randomized phase III trial data. We conducted an analytic review of the literature with the objective of identifying the usefulness of 5-ALA and FS in HGG surgery in adult patients.