Hydrogels for biomedical applications from glycol chitosan and PEG diglycidyl ether exhibit pro-angiogenic and antibacterial activity.

We aimed at producing a hydrogel from a chitosan (CS) derivative soluble in physiological conditions to avoid any purification step thus allowing to use the materials also as an in-situ forming material. So, we crosslinked glycol chitosan (GCS) with poly(ethylene glycol) diglycidyl ether (PEGDE) in water at 37 °C. The scaffolds, referred as GCS-PEG, were specifically designed to be used as wound dressing materials as such (after crosslinking) or as in-situ forming materials. Different amounts of PEGDE were tested. The obtained scaffolds showed macroscopic pores and a tailorable swelling in water by controlling the crosslinking degree. Moreover, GCS-PEG scaffolds displayed a significant antimicrobial activity against Staphylococcus aureus. In-vivo study using the chick embryo choriallantoic membrane resulted in a highly pronounced pro-angiogenic activity suggesting important tissue regeneration properties. Moreover, the employed materials are commercially available, no organic solvents are required and the scaling up is quite predictable.

Nanoparticle delivery of grape seed-derived proanthocyanidins to airway epithelial cells dampens oxidative stress and inflammation.

BACKGROUND: Chronic respiratory diseases, whose one of the hallmarks is oxidative stress, are still incurable and need novel therapeutic tools and pharmaceutical agents. The phenolic compounds contained in grape are endowed with well-recognized anti-oxidant, anti-inflammatory, anti-cancer, and anti-aging activities. Considering that natural anti-oxidants, such as proanthocyanidins, have poor water solubility and oral bioavailability, we have developed a drug delivery system based on solid lipid nanoparticles (SLN), apt to encapsulate grape seed extract (GSE), containing proanthocyanidins. METHODS: Plain, 6-coumarin (6-Coum), DiR- and GSE-loaded SLN were produced with the melt-emulsion method. Physicochemical characterization of all prepared SLN was determined by photon correlation spectroscopy and laser Doppler anemometry. MTT assay (spectrophotometry) and propidium iodide (PI) assay (cytofluorimetry) were used to assess cell viability. Flow cytometry coupled with cell imaging was performed for assessing apoptosis and necrosis by Annexin V/7-AAD staining (plain SLE), cell internalization (6-Coum-SLN) and reactive oxygen species (ROS) production (SLN-GSE). NF-κB nuclear translocation was studied by immunofluorescence. In vivo bio-imaging was used to assess lung deposition and persistence of aerosolized DiR-loaded SLN. RESULTS: Plain SLN were not cytotoxic when incubated with H441 airway epithelial cells, as judged by both PI and MTT assays as well as by apoptosis/necrosis evaluation. 6-Coum-loaded SLN were taken up by H441 cells in a dose-dependent fashion and persisted into cells at detectable levels up to 16 days. SLN were detected in mice lungs up to 6 days. SLN-GSE possessed 243 nm as mean diameter, were negatively charged, and stable in size at 37 °C in Simulated Lung Fluid up to 48 h and at 4 °C in double distilled water up to 2 months. The content of SLN in proanthocyanidins remained unvaried up to 2 months. GSE-loaded SLN determined a significant reduction in ROS production when added 24-72 h before the stimulation with hydrogen peroxide. Interestingly, while at 24 h free GSE determined a higher decrease of ROS production than SLN-GSE, the contrary was seen at 48 and 72 h. Similar results were observed for NF-κB nuclear translocation. CONCLUSIONS: SLN are a biocompatible drug delivery system for natural anti-oxidants obtained from grape seed in a model of oxidative stress in airway epithelial cells. They feature stability and long-term persistence inside cells where they release proanthocyanidins. These results could pave the way to novel anti-oxidant and anti-inflammatory therapies for chronic respiratory diseases.

Nociceptin (1-13)NH2 inhibits stimulated calcitonin-gene-related-peptide release from primary cultures of rat trigeminal ganglia neurones.

In this work we have developed and characterized primary cultures of neonatal rat trigeminal ganglia neurones; calcitonin-gene-related-peptide (CGRP) released from cells was taken as a marker of neuronal function. A significant and consistent increase in CGRP secretion was elicited by non-specific (56 mm KCl or veratridine) or specific (capsaicin) depolarizing stimuli. This paradigm was subsequently used to investigate the effects of nociceptin, an opioid-like peptide involved in central and peripheral control of nociception. We found that the nociceptin analogue nociceptin (1-13)NH2 (NOC) did not affect baseline CGRP release, but it reduced in a concentration-dependent manner CGRP release induced by all tested stimuli. NOC-induced reduction was statistically significant from 0.01 nm onward and achieved maximal effects at 10 nm. Such effects of NOC were seemingly mediated by the activation of specific ORL1 receptors, as a well-known nociceptin antagonist, N(Phe1)nociceptin (1-13)NH2, was able to completely revert NOC inhibition of capsaicin-stimulated CGRP release.

Effects of different cyclodextrins on the morphology, loading and release properties of poly (DL-lactide-co-glycolide)-microparticles containing the hypnotic agent etizolam.

The aim of this study was to gain insight into the feasibility of using microparticles (MPs) constituted by the biodegradable poly (DL-lactide-co-glycolide) (PLGA) and a number of cyclodextrins (CDs) as an orally sustained delivery system of the hypnotic agent etizolam (ETZ). A further aim of the work was to investigate the effects of different CDs on the morphology, loading, and release properties of the MPs prepared. For these purposes, ETZ alone, and ETZ/CD-PLGA loaded MPs were prepared by the W/O/W emulsion-solvent evaporation method. It was found that the release of ETZ in vitro was more prolonged over three days with a kinetic constant proportional to t(1/2). It was also demonstrated that the CDs in these MPs are able to modulate several properties such as morphology, drug loading, and release properties. In fact, marked differences in shape, surface, and encapsulation efficiencies were noted depending on the presence, hydrophilicity, and charge of the CD employed. The obtained results induce us to consider the present ETZ-containing formulations as new valuable tools for the treatment of different insomnia categories.

A safe immunosuppressive protocol in adult-to-adult living related liver transplantation.

BACKGROUND: In this series of 32 adult-to-adult living related liver transplantations, we assessed the efficacy and safety of basiliximab in combination with a tacrolimus-based regimen. Basiliximab, a chimeric monoclonal antibody directed against the alpha chain of the interleukin-2 (IL-2) receptor (CD25), has been extensively evaluated as induction therapy for cadaveric liver transplant recipients. PATIENTS AND METHODS: Thirty-two adult-to-adult living related liver transplantations were performed in the last 3 years. All patients received two 20 mg doses of basiliximab (days 0 and 4 posttransplantation) followed by tacrolimus (0.15 mg/kg/d; 10-15 ng/mL target trough levels) and steroids (starting with 20 mg IV switched to PO as soon as the patient was able to eat and weaned within 1-2 months). The average follow-up was 395 days after transplantation. RESULTS: Of the patients, 93.75% remained rejection-free during follow-up with an actuarial rejection-free probability of 92.59% within 3 months. Two patients (6%) had one episode of biopsy-proven acute cellular rejection (ACR). Actuarial patient and graft survival rates at 3 years were 86.85% and 81.25%. One patient (3%) experienced one episode of sepsis. There was no evidence of cytomegalovirus infections or side effects related to the basiliximab. We found zero de novo malignancy but we observed two patients with metastatic spread of their primary malignancy during the follow-up. CONCLUSION: Basiliximab in association with tacrolimus and steroids is effective as prophylaxis of ACR among adult living related liver transplant recipients.

Dysfunction of arousal systems in sleep-related migraine without aura.

Primary headaches are closely related to sleep. Modifications in the patterns of arousal during sleep have been reported in migraine, especially in the nights preceding a headache attack. We aimed at evaluating the pattern of arousal from sleep in a group of patients affected by sleep-related migraine. We enrolled 10 consecutive patients, three males and seven females, aged between 20 and 62 years, who presented frequent attacks of migraine without aura (more than five per month), closely related to sleep (more than one-half of the attacks occurred during sleep, causing an awakening). A control group was studied, matched for age and sex. Patients and controls underwent a full-night polysomnographic study, following adaptation; arousal pattern was studied by the scoring of the high-frequency EEG arousal and by the cyclic alternating pattern (CAP). Migraineurs showed a lower CAP rate in non-rapid eye movement (NREM) sleep and, in particular, a lower number of A1 phases (low-frequency, high-amplitude EEG bursts) compared with the controls. Migraineurs also showed a lower index of high-frequency EEG arousals during rapid eye movement (REM) sleep. The reduction in the CAP rate indicates a lower level of arousal fluctuation in NREM sleep. The reduced arousal index in REM suggests a dysfunction in neural structures involved in both the control of REM sleep and the pathophysiology of migraine, such as the hypothalamus and the brainstem.

A sleep study in cluster headache.

Cluster headache (CH) is a primary headache with a close relation to sleep. CH presents a circa-annual rhythmicity; attacks occur preferably during the night, in rapid eye movement (REM) sleep, and they are associated with autonomic and neuroendocrine modifications. The posterior hypothalamus is the key structure for the biological phenomenon of CH. Our aim is to describe a 55-year-old man presenting a typical episodic CH, in whom we performed a prolonged sleep study, consisting of a 9-week actigraphic recording and repeated polysomnography, with evaluation of both sleep macrostructure and microstructure. During the acute bout of the cluster we observed an irregular sleep-wake pattern and abnormalities of REM sleep. After the cluster phase these alterations remitted. We conclude that CH was associated, in this patient, with sleep dysregulation involving the biological clock and the arousal mechanisms, particularly in REM. All these abnormalities are consistent with posterior hypothalamic dysfunction.

Multiple attack study on the available triptans in Italy versus placebo.

The aim of the study is to evaluate the efficacy and tolerability of the five triptans that are commercially available in Italy (zolmitriptan 2.5 mg, rizatriptan 10 mg, sumatriptan 100 mg, almotriptan 12.5 mg and eletriptan 40 mg). The study was conducted in single-blind versus placebo and its duration was 18 months. At the Headache Centre of the 'Agostino Gemelli' Hospital in Rome we selected 42 patients, suffering from headache with and without aura (International Headache Society Committee on Headache Classification, 1988 Cephalalgia 8:1-96), whose headache frequency ranged between 1- and 4-monthly crises. For a total of 25 crises, for every five consecutive crises, a different triptan was taken. The end-points of the study were as follows: response at 2 h, 'pain free' at 2 h and 'sustained pain free' (at 24 h). The intra-patient consistency and the tolerability were also evaluated. Thirty patients completed the study and the statistical analysis was only applied to these patients. No substantial difference in terms of the efficacy of the triptans was noted; all triptans were well tolerated. These results suggest the possibility of testing different triptans in the same patient in order to identify the ideal drug for every patient.

Topiramate in migraine prophylaxis: a randomised double-blind versus placebo study.

The objectives of this paper are to evaluate the efficacy and tolerability of topiramate, given at the dose of 100 mg/day, in the prophylactic treatment of migraine. The hypothesis that migraine is the result of a condition of neuronal hyperexcitability and the quest for drugs that are able to limit the number of crises justifies the attempt to utilise the new antiepileptic drugs in the prophylaxis of this pathology, which is so important due to its high prevalence and due to the high disability it causes. The study was randomised double-blind versus placebo, lasting 16 weeks, and was preceded by a run-in period of 4 weeks. One hundred and fifteen patients were randomly allocated to treatment with topiramate (TPM) or placebo: 35 patients completed the study in the TPM group and 37 patients in the placebo group. At the end of the double-blind phase of study, in the TPM group, we recorded a significant reduction in the frequency of migraine crises (from 5.26 at baseline to 2.60 in the last 4 weeks), a significant reduction in the quantity of symptomatic drugs taken as compared to the placebo control group (from 6.17+/-1.80 SD to 2.57+/-0.80) and a significant downward trend in the number of days of disability over the 16-week period of therapy. In the TPM group, side effects were transient and well tolerated. TPM has thus proven its efficacy and tolerability in the prophylaxis of migraine.

Internal auditory canal metastasis.

This report deals with 3 cases of internal auditory canal metastasis, an extremely rare lesion, few cases having been reported in the international literature. Since pre-operative diagnosis is fundamental in the planning of a correct therapeutic strategy, it is important that the neurotologist be aware of the possibility of their occurrence in this particular area. Metastasis can occur unilaterally as well as bilaterally; the latter being the case in 1 of the patients described herein. Correct pre-operative diagnosis is particularly difficult in patients in whom the primary tumour has not been detected at the time of identification of the lesion in the internal auditory canal. The only characteristic, specific of metastasis, is the presence of multifocal cerebral lesions. However, these were detected in only 1 of the present cases. On the contrary, in cases of a single metastasis, both magnetic resonance imaging and computed tomography usually fail to show any distinctive feature when compared to the most common tumours of the internal auditory canal (vestibular schwannomas and meningiomas). Bilateral metastases can also be misdiagnosed as neurofibromatosis type 2. Clinical data that should alert the clinician are: rapidly progressive sensorineural hearing loss, followed by onset of progressive facial nerve weakness. Radiotherapy and/or chemotherapy are the two main treatment modalities, while surgical removal is reserved for selected cases of a single metastasis. Albeit, due to the paucity of specific radiological and clinical characteristics, surgical removal is often necessary to reach the correct diagnosis, as occurred in 2 of the present patients.

Antiepileptic drugs in migraine prophylaxis: state of the art.

Antiepileptic drugs have proven their efficacy in the prophylactic treatment of migraine. Our study comprises a clinical trial that examines the efficacy of gabapentin and topiramate and a description of the pharmacologic characteristics and the efficacy of tiagabine, lamotrigine, levetiracetam and zonisamide. Antiepileptic drugs have multiple modes of action which can explain their efficacy in reducing neuronal excitability which is proven in epilepsy and postulated in migraine. The relationship between epilepsy and migraine has, in fact, been much debated but never convincingly proven. Antiepileptic drugs could be useful in migraine prophylaxis as some of these have determined a reduction in the monthly frequency and intensity of crises in subjects suffering from migraine with and without aura. These are the aims that have been proposed by the U.S. Headache Consortium Evidence-Based Guidelines. Further double-blind placebo-controlled studies are necessary in order to assess their safety and efficacy.

Valproic acid-hydrophilic cyclodextrin complexes and valproic acid-solid dispersions: evaluation of their potential pharmaceutical use.

The purpose of this study was to evaluate the potential use of two novel solid formulations of valproic acid (VPA) prepared by complexation with hydrophilic cyclodextrins (CDs) as hydroxypropyl-beta- and sulfobutylether-beta-cyclodextrin and by solid dispersion (SD) in hydrophilic carriers as polyethylene glycol 6000 (PEG 6000) and polyvinylpyrrolidone K-30 (PVP K-30). The corresponding cyclodextrin-based complexes were prepared by the freeze-drying method while the solid dispersions were obtained by the solvent method. Valproic acid solubility improved by CDs complexation and solid dispersion techniques. Comparison of dissolution profiles with that of VPA sodium salt (NaVP) was made by using release parameters such as dissolution efficiency, percent of drug dissolved after 60 min, and difference and similarity factors. Based on difference and similarity factors, it can be concluded that all the VPA formulations possess dissolution profiles essentially equivalent to those of NaVP at pH 6. However, this conclusion is not confirmed by using the analysis of variance (ANOVA) approach, indicating some significant differences between some SD-based formulations and NaVP at that pH value. Preliminary pharmacological studies in the pentylenetetrazole test in rats showed some important differences among the SD-based formulations, NaVP, and VPA as oil/water emulsion. Some implications and limitations of the investigated formulations are discussed.

Reduced habituation to experimental pain in migraine patients: a CO(2) laser evoked potential study.

The habituation to sensory stimuli of different modalities is reduced in migraine patients. However, the habituation to pain has never been evaluated. Our aim was to assess the nociceptive pathway function and the habituation to experimental pain in patients with migraine. Scalp potentials were evoked by CO(2) laser stimulation (laser evoked potentials, LEPs) of the hand and facial skin in 24 patients with migraine without aura (MO), 19 patients with chronic tension-type headache (CTTH), and 28 control subjects (CS). The habituation was studied by measuring the changes of LEP amplitudes across three consecutive repetitions of 30 trials each (the repetitions lasted 5 min and were separated by 5-min intervals). The slope of the regression line between LEP amplitude and number of repetitions was taken as an index of habituation. The LEPs consisted of middle-latency, low-amplitude responses (N1, contralateral temporal region, and P1, frontal region) followed by a late, high-amplitude, negative-positive complex (N2/P2, vertex). The latency and amplitude of these responses were similar in both patients and controls. While CS and CTTH patients showed a significant habituation of the N2/P2 response, in MO patients this LEP component did not develop any habituation at all after face stimulation and showed a significantly lower habituation than in CS after hand stimulation. The habituation index of the vertex N2/P2 complex exceeded the normal limits in 13 out of the 24 MO patients and in none of the 19 CTTH patients (P<0.0001; Fisher's exact test). Moreover, while the N1-P1 amplitude showed a significant habituation in CS after hand stimulation, it did not change across repetitions in MO patients. In conclusion, no functional impairment of the nociceptive pathways, including the trigeminal pathways, was found in either MO or CTTH patients. But patients with migraine had a reduced habituation, which probably reflects an abnormal excitability of the cortical areas involved in pain processing.

Occupational head injury and subsequent glioma.

We report the case of a policeman who suffered a severe head injury to the right temporoparietal lobe while driving a police car. Four years later, the patient developed a neoplasm at the precise site of the meningocerebral scar. Histological examination confirmed a glioblastoma multiforme adjacent to the dural scar. Radiological documentation of the absence of tumor at the time of injury, exact localization of the neoplasm in the injured cerebral area, and latency of the cancer supported the hypothesis of a causal relationship with brain trauma. Physicians faced with brain neoplasms in adults should carefully investigate the patient's personal history of head trauma. When a relationship with occupational head injury is probable, reporting of suspect occupational illness is compelling.

Wine in the prevention of chronic bacterial urinary infection.

The observation of statistical public health data, together with lifestyle in a still native population following a strict Mediterranean diet, where local wine consumption of approximately 350 ml daily still has a primary role, demonstrates that this area, Pantelleria, also called the Black Pearl, has better regulation of common intestinal motor disorders. The incidence of chronic bacterial urinary infection is 30% lower than the national average. Further open laboratory studies should be performed to confirm our data and to elucidate whether protection against chronic bacterial urinary infection is congenital or acquired.

Peripheral neuropathy with hypomyelinating features in adult-onset Krabbe's disease.

We describe three brothers suffering from Krabbe's disease with onset in the fifth decade. The proband showed a complete deficiency of leukocyte enzyme galactocerebrosidase and was found to be heterozygous for two previously described mutations: G > A809 and 502T/del consisting of a 30 kb deletion. In all three brothers the neurological examination showed features of asymmetrical peripheral neuropathy associated with pyramidal signs and the electrophysiological examination showed a generalized slowing of nerve conduction velocities. Two patients died at 59 and 61 years of age due to respiratory failure. Both the proband and his brother underwent a sural nerve biopsy. In the former the most striking finding was the presence of uniformly thin myelin sheaths without evidence of demyelination; a complete absence of fibers was found in the latter. Our findings confirm that peripheral neuropathy may be the presenting feature of late-onset Krabbe's disease. Hypomyelination rather than demyelination may represent the distinguishing pathological finding of this condition.

Changes in GABA(A) receptor gene expression induced by withdrawal of, but not by long-term exposure to, zaleplon or zolpidem.

The effects of long-term treatment with and subsequent withdrawal of the two hypnotic drugs zaleplon and zolpidem on the abundance of gamma-aminobutyric acid type A (GABA(A)) receptor subunit mRNAs in cultured rat cerebellar granule cells were investigated. Incubation of neurons with either drug at a concentration of 10 microM for 5 days did not significantly affect the amounts of mRNAs encoding the alpha(1), alpha(4), beta(1), beta(2), beta(3), gamma(2)L, or gamma(2)S subunits. As expected, similar treatment with the nonselective benzodiazepine diazepam resulted in a decrease in the abundance of alpha(1), beta(2), gamma(2)L, and gamma(2)S subunit mRNAs as well as an increase in that of the beta(1) subunit mRNA. Withdrawal of zaleplon or zolpidem, like that of diazepam, induced a marked increase in the amount of the alpha(4) subunit mRNA. In addition, discontinuation of treatment with either hypnotic drug resulted in a decrease in the amounts of alpha(1), beta(2), gamma(2)L, and gamma(2)S subunit mRNAs as well as an increase in that of the beta(1) subunit mRNA. These effects of zaleplon and zolpidem on GABA(A) receptor gene expression are consistent with the reduced tolerance liability of these drugs, compared with that of diazepam, as well as with their ability to induce both physical dependence and withdrawal syndrome.

Binding of [3H]CB 34, a selective ligand for peripheral benzodiazepine receptors, to rat brain membranes.

The 2-phenyl-imidazo[1,2-a]pyridine derivative CB 34 is a ligand for peripheral benzodiazepine receptors. The binding of [3H]CB 34 to rat cerebrocortical membranes was characterized. Specific binding was rapid, reversible, saturable and of high affinity. Kinetic analysis yielded association and dissociation rate constants of 0.2x10(8) M(-1) min(-1) and 0.29 min(-1), respectively. Saturation binding experiments revealed a single class of binding sites with a total binding capacity of 188+/-8 fmol/mg protein and an apparent dissociation constant of 0.19+/-0.02 nM. Specific [3H]CB 34 binding was inhibited by ligands selective for peripheral benzodiazepine receptors, whereas, with the exception of flunitrazepam and diazepam, ligands for central benzodiazepine receptors were inactive. Of the brain regions examined, the density of the [3H]CB 34-binding sites was greatest in the hypothalamus and lowest in the cerebral cortex. [3H]CB 34 is thus a potent and selective ligand for peripheral benzodiazepine receptors and should be proven useful for studies of the roles of these receptors.