Biomedical subjects

L Santoro

Publications and source records attributed to L Santoro.

At least 37 records · Page 2Linked to original sources

PubMed2003

Neurophysiologic evaluation of central-peripheral sensory and motor pudendal pathways in primary premature ejaculation.

OBJECTIVES: Pudendal nerve somatosensory evoked potentials (SEPs), the bulbocavernosus (BC) reflex, and BC perineal motor evoked potentials after transcranial magnetic cortical stimulation were performed in patients with primary premature ejaculation to investigate the somatic sensory and motor function of the genital area. METHODS: Fourteen patients with primary premature ejaculation underwent psychological counseling, urologic physical examination, transrectal ultrasound examination, laboratory testing, and the Stamey test. The spinal and cortical pudendal nerve SEPs were performed by dorsal nerve stimulation at the penile shaft (DN-SEPs) in all patients and at the glans penis (GP-SEPs) in 3 of them. The BC reflex was obtained by stimulating the base of the penis. RESULTS: The mean sensory threshold did not significantly differ between the patients and normal subjects. Cortical DN-SEPs were normal in all patients. The sensory central conduction time, calculated in 6 patients, was normal. The mean cortical DN-SEP amplitude was significantly smaller in patients than in controls. In 3 patients and in 3 controls who underwent both DN-SEP and GP-SEP testing, the glans penis sensory threshold was lower than the dorsal nerve threshold and the cortical GP-SEP latency was longer than the cortical DN-SEP latency. The BC reflex was normal in most patients. The BC motor evoked potentials were normal in all patients, but one. CONCLUSIONS: We did not confirm either a faster conduction along the pudendal sensory pathway or a greater cortical representation of the sensory stimuli from the genital area in our patients. Moreover, we did not confirm hyperexcitability of the BC reflex in them. Our results suggest that the electrophysiologic approach is probably not sufficient to clarify the causes of primary premature ejaculation. A more integrated investigation could allow better results in this field.

Adult↗

PubMed2003

Is Ross syndrome a dysautonomic disorder only? An electrophysiologic and histologic study.

OBJECTIVE: To define the involvement of peripheral nerve fibers in Ross syndrome. METHODS: Mechanical pain perception, tactile and thermal thresholds on hand, foot dorsum, thigh, median nerve orthodromic sensory conduction velocity (SCV) and motor conduction velocity (MCV), sural nerve antidromic SCV, peroneal nerve MCV, H-reflex, F-wave, median, tibial nerve somatosensory evoked potentials (SSEPs), perioral, hand CO(2) laser late (LEPs) and ultralate evoked potentials, sympathetic skin response (SSRs), cardiovascular, Minor sweat, silastic imprint, histamine, photopletysmographic and pupil pilocarpine tests, cutaneous innervation immunohistochemical techniques were studied in 3 patients with Ross syndrome. RESULTS: Quantitative sensory testing showed altered results in patients 1 and 2, and patient 3 had a slight impairment of mechanical pain perception. Nerve conduction, except for a median nerve distal reduction of sensory conduction in patient 1, F-wave and SSEP findings were normal; H-reflex was absent at rest in all patients. Hand LEPs were absent in patient 2, ultralate potentials were absent in patients 1 and 2. Skin biopsy showed a disease duration related reduction of unmyelinated and myelinated sensory fibers and a lack of unmyelinated autonomic fibers in all patients. CONCLUSIONS: Our data suggest that Ross syndrome is a degenerative disorder involving progressive sudomotor fibers, and then epidermal sensory unmyelinated and myelinated fibers.

Adult↗

PubMed2003

Heavy metal stabilization by means of innovative alumino-silicate matrix.

Powdered tuff mixed with NaOH solution has been hydrothermally cured at temperatures ranging from 90 to 150 degrees C. Hardening takes place due to the formation of an amorphous binding phase. At the lowest temperature tested a non-autoclaved process can be carried out. Values of unconfined compressive strength were found to vary from 15.5 MPa to 28.9 MPa depending on reaction conditions. The matrix was tested as a binder for the stabilization of model systems containing cadmium, chromium and lead and for a real system containing a secondary lead smelter slag. The stabilization process was tested from both the environmental and technological points of view by means of leahcing tests and compressive strength measurement. Basic characterization leaching tests carried out with the model systems showed that metal release from hardened paste is below 1%. Compliance leaching test carried out with the real system showed that lead release is below the limit set by law. From the technological pont of view, it was found that unconfined compressive strength is always higher for the real system. Specifically, this system showed compressive strength increasing with slag content to values exceeding 86.5 MPa.

Aluminum Silicates↗

PubMed2003

Temporal evolution and functional outcome of no reflow: sustained and spontaneously reversible patterns following successful coronary recanalisation.

OBJECTIVE: To identify in humans the temporal patterns of no reflow and their functional implications. METHODS: 24 patients with first acute myocardial infarction and successful coronary recanalisation by recombinant tissue-type plasminogen activator (n = 15) or primary percutaneous transluminal coronary angioplasty (n = 9) were studied by myocardial contrast echocardiography within 24 hours of recanalisation and at one month's follow up. Myocardial contrast echocardiography was performed by intermittent harmonic power Doppler and intravenous Levovist. The regional contrast score index (CSI) was calculated within dysfunctioning myocardium. Videointensity was measured (dB) within risk and control areas and their ratio was calculated. RESULTS: In 8 patients reflow was observed at 24 hours and persisted at one month. Conversely in 16 patients areas of no reflow were detectable at 24 hours. At one month, no reflow was spontaneously reversible in 9 patients (mean (SD) CSI and videointensity ratio improved from 2.5 (0.5) to 1.4 (0.6) and from 0.6 (0.1) to 0.7 (0.1), respectively; p < 0.05) and was sustained in the remaining 7 patients (CSI and videointensity ratio remained unchanged from 2.6 (0.6) to 2.6 (0.5) and from 0.5 (0.2) to 0.5 (0.2), respectively; NS). Left ventricular function improved significantly in patients with reflow and reversible no reflow. Volumes were enlarged only in patients with sustained no reflow. CONCLUSIONS: No reflow detected at 24 hours may be sustained or spontaneously reversible at one month. Such reversibility of the phenomenon is associated with preserved left ventricular volumes and function. Clarification of the mechanisms of delayed reversibility may lead to tailored treatment of no reflow even in the subacute phase of myocardial infarction.

Angioplasty, Balloon, Coronary↗

PubMed2003

Acute inflammatory demyelinating polyradiculoneuropathy associated with perforin-deficient familial haemophagocytic lymphohistiocytosis.

UNLABELLED: This study reports the first paediatric case of acute inflammatory demyelinating polyradiculoneuropathy (AIDP) associated with a fatal haemophagocytic lymphohistiocytosis (HLH). The patient developed progressive weakness of the lower limbs in the context of a picture of infectious mononucleosis and Epstein-Barr virus (EBV) infection. After an apparent improvement, a fulminant hepatic failure and pancytopenia ensued, leading to death. Molecular genetic studies documented a compound heterozygosity for two mutations in the perforin (PRF1) gene as the background defect for a familial haemophagocytic lymphohistiocytosis (FHL). CONCLUSION: In this patient EBV infection triggered both AIDP and FHL. The latter condition was due to PRF1 deficiency. Two novel mutations in the PRF1 gene were concomitantly present in the patient. The first caused an amino acid change, while the second introduced a stop codon in the sequence which resulted in a truncated protein.

Child↗

PubMed2002

Environmental and technological effectiveness of a process for the stabilization of a galvanic sludge.

A binding matrix containing calcium silicate beta-2CaO.SiO(2) and sulphoaluminate 4CaO.3Al(2)O(3).SO(3), and CaSO(4) that gives calcium silicate and trisulphoaluminate hydrates upon hydration has been used for the stabilization of a solid waste from a galvanic treatment process. The waste is to be disposed of in a hazardous wastes landfill to prevent the risk of cadmium, chromium and nickel release. Anhydrous calcium silicate and sulphoaluminate of the binder have been synthesized using a mixture containing powdered tuff in addition to bauxite and calcium carbonate and sulphate. Powdered tuff is quarry dust and is, as such, a true residue. Experiments have been carried out with mixtures containing up to 60% waste and have been addressed towards the environmental and technological assessment of the effectiveness of the stabilization process. Specifically, the study has been carried out taking into account requirements from three different points of view, that is the influence of the waste on the hydration process and on the technological properties of the stabilized products, the leaching behavior under some selected conditions and the effect of the leaching medium on the binding matrix in the stabilized system.

Calcium Compounds↗

PubMed2002

Charcot-Marie-Tooth disease type 2C: a distinct genetic entity. Clinical and molecular characterization of the first European family.

Charcot- Marie-Tooth disease type 2 is clinically and genetically heterogeneous. A particular clinical subtype of autosomal dominant Charcot-Marie-Tooth disease type 2, characterized by diaphragm and vocal cord paralysis, is labelled Charcot-Marie-Tooth disease type 2C but no genetic locus has been mapped for this form. We describe the first European family affected by Charcot-Marie-Tooth disease type 2C. Genetic analysis excluded linkage to locus of Charcot-Marie-Tooth disease type 2A, B, D, E and F, and to locus of distal hereditary motor neuronopathy type VII. In this family the disease has high penetrance, variable severity and apparently the most severe limb muscle involvement in the youngest generation. Vocal cord paralysis is unrelated to the degree of muscular weakness and patients with the most severe muscle involvement have absent or minimal respiratory symptoms. Charcot-Marie-Tooth disease type 2C is clinically and genetically different from Charcot-Marie-Tooth disease type 2A, B, D, E and F, and is not allelic with distal hereditary motor neuronopathy type VII.

Adult↗

PubMed2002

Cement stabilization of tannery sludge using quaternary ammonium salt exchanged bentonite as pre-solidification adsorbent.

In this paper a cement-based cementitious system is studied for the stabilization of tannery sludge. Two binders were used as stabilizing matrices: pozzolanic cement alone and a 3:7 cement/blast furnace slag mixture. Due to the high organic content of the sludge, organophilic bentonite was added to the stabilization system; the modified bentonite was obtained by ionic exchange with benzyldimethyloctadecylammonium chloride and proved to be an effective sorbent of the organic components of the sludge. The different process steps were arranged to minimize the water requirement. The process was evaluated from three different points of view: chemicaL environmental and technological. From the chemical point of view, it was found that the binder hydration products are unaffected by the presence of sludge, although the hydration process is retarded. From the environmental and technological points of view, it was found that the presence of organophilic bentonite strongly enhances process performance. In fact, th e release of both organic carbon and chromium is greatly reduced and the unconfined compressive strength of the stabilized products is increased. According to Italian standards, the stabilized products are suitable for the manufacture of pre-formed building blocks.

Adsorption↗

PubMed2001

Excitatory and inhibitory mechanisms in Wilson's disease: investigation with magnetic motor cortex stimulation.

We have evaluated cortical excitability in nine patients affected by Wilson's disease (WD) using transcranial magnetic (TMS) and electric (TES) cortical stimulation and central silent period (CSP) data. A clinical score was derived from the sum of scores assigned to extrapyramidal, pyramidal and cerebellar signs. All patients underwent TMS. Motor evoked potentials (MEPs) from abductor pollicis brevis (APB) and tibialis anterior (TA) muscles were recorded. MEP threshold and amplitude, central motor conduction time (CMCT), CSP threshold, CSP and peripheral silent period (PSP) duration were measured. Three patients also underwent transcranial bifocal electric cortical stimulation (TES) and MEPs were recorded from the APB muscle, and CMCT, MEP threshold and amplitude were measured. TMS MEPs were absent from relaxed muscles in six patients and from contracted muscles in three. CMCT was prolonged in six patients. APB CMCT correlated with clinical score. In three patients in whom TMS revealed abnormal or no MEP, TES MEPs were of normal threshold and amplitude. The CSP threshold was increased in seven patients, and CSP was absent in one. These results suggest an intracortical presynaptic motor dysfunction in WD.

Adult↗

PubMed2001

Case of Myhre syndrome with autism and peculiar skin histological findings.

Myhre syndrome (MS) (MIM 139210) is a rare disorder characterized by short stature, mental retardation, muscular build, blepharophimosis, and decreased joint mobility. We report on a 14-year-old boy with clinical findings consistent with a diagnosis of Myhre syndrome, associated with autism and peculiar skin histological findings.

Abnormalities, Multiple↗

PubMed2001

Multiple sclerosis retrovirus particles and recombinant envelope trigger an abnormal immune response in vitro, by inducing polyclonal Vbeta16 T-lymphocyte activation.

A retroviral element (MSRV) defining a family of genetically inherited endogenous retroviruses (HERV-W) has recently been characterized in cell cultures from patients with multiple sclerosis (MS). To address the possible relationship with MS, direct detection of circulating virion RNA was proposed but revealed technically difficult to perform in standardized conditions, in the face of multiple endogenous HERV-W copies. A parallel approach has evaluated MSRV potential pathogenicity in relation to characteristic features of multiple sclerosis, in particular, T-lymphocyte-mediated immunopathology. We report here that MSRV particles induce T-lymphocyte response with a bias in the Vbeta16 chain usage in surface receptor, whatever the HLA DR of the donor. A recombinant MSRV envelope-but not core-protein reproduced similar nonconventional activation. Molecular analysis of Vbeta CDR3 showed that Vbeta16 expansions are polyclonal. Our results thus provide evidence that MSRV envelope protein can trigger an abnormal immune response with similar characteristics to that of superantigens.

Antigens, Viral↗

PubMed2001

Adult-onset familial laryngeal abductor paralysis, cerebellar ataxia, and pure motor neuropathy.

Two brothers presented with late-onset cerebellar ataxia and severe dysphonia. Brain MRI showed vermian and hemispheric cerebellar atrophy. Laringofiberscopy revealed laryngeal abductor paralysis in both patients. Neurophysiologic studies showed a pure motor neuropathy. The combined findings and the molecular analysis suggest a new familial disorder. Inheritance is most likely autosomal recessive, but X-linked transmission is also possible.

Aged↗

PubMed2001

Small fibers involvement in Friedreich's ataxia.

Although the involvement of large myelinated sensory fibers in Friedreich's ataxia (FA) is well documented, an impairment of unmyelinated fibers has not been described. We demonstrate an involvement of cutaneous unmyelinated sensory and autonomic nerve fibers in FA patients. We performed a morphological and functional study of cutaneous nerve fibers in 14 FA patients and in a population of control subjects. We used immunohistochemical techniques and confocal microscopy applied to punch skin biopsies from thigh, distal leg, and fingertip, and compared the density of epidermal nerve fibers (ENFs) with the results of mechanical pain sensation and thermal and tactile thresholds performed on hand dorsum, thigh, distal leg, and foot dorsum. We observed in our patients a statistically significant loss of ENFs, a reduced innervation of sweat glands, arrector pilorum muscles and arterioles, and an impairment of thermal and tactile thresholds and mechanical pain detection.

Adolescent↗

PubMed2001

T2 relaxometry of brain in myotonic dystrophy.

We investigated the nature and extent of brain involvement in myotonic dystrophy (DM), examining possible T2 relaxation abnormalities in the brain of 20 patients with adult-onset DM and 20 sex- and age-matched normal controls. Brain MRI was performed at 0.5 T, and T2 values were calculated from signal intensity in two echoes. Regions of interest included: frontal, parietal, temporal, occipital and callosal (rostral and splenial) normal-appearing white matter; frontal, occipital, insular and hippocampal cortex; caudate nucleus, putamen, globus pallidus and thalamus. All white-matter and occipital and right frontal cortex regions showed a significantly longer T2 in the patients. Multiple regression analysis, including grey- and white-matter T2 as dependent variables, plus age at onset and at imaging, disease duration, muscular disability, brain atrophy and CTG trinucleotide repeats as independent variables, revealed that only white-matter T2 elongation and disease duration correlated positively. White-matter involvement in DM is more extensive than previously reported by MRI and neuropathological studies and seems to be progressive in the course of disease.

Adolescent↗

PubMed2001

Temporal integration of optic flow, measured by contrast and coherence thresholds.

We measured, as a function of exposure duration, contrast sensitivity and coherence sensitivity for discerning the direction of motion of random dot patterns moving in circular, radial or translational directions. Contrast sensitivity for these patterns increased linearly with exposure duration, up to about 200-300 ms, consistent with previous estimates of temporal summation of early motion units. Coherence sensitivity, however, showed much longer summation periods, about 3 s. When the stimulus was embedded within 10 s of noise, sensitivity increased with duration up to 2-3 s, approximately linearly, as expected from an ideal integrator. When presented without the noise period, sensitivity also increased, but in a different way. For radial and circular motion the increase tended towards the theoretically predicted square root relationship for the same duration as that found with the embedded noise (about 3 s). For translation, however, the curve was steeper than the theoretical prediction (nearly linear), and the summation estimates of around 1000 ms. When the duration of the target was constant at 200 ms, but that of the flanking noise varied, sensitivity decreased with total duration over a similar interval. We interpret our results to reflect at least two stages of analysis, a threshold-limited early stage of local-motion analysis, with a time constant of 200-300 ms, and a later global-motion integration stage with a much longer time constant, around 3000 ms. There may also exist an intermediate stage, with an integration time of around 1000 ms.

Adult↗

PubMed2001

Stabilization of chloro-organics using organophilic bentonite in a cement-blast furnace slag matrix.

The application of cement-based stabilisation/solidification treatment to organic-containing wastes is made difficult by the adverse effect of organics on cement hydration. The use of organophilic clays as pre-solidification adsorbents of the organic compounds can reduce this problem because of the high adsorption power of these clays and their compatibility with the cementitious matrix. This work presents an investigation of the effect on hydration kinetics, physico-mechanical properties and leaching behaviour of cement-based solidified waste forms containing 2-chlorophenol and 1-chloronapthalene adsorbed on organophilic bentonites. These were prepared by cation exchange with benzyldimethyloctadecylammonium chloride and trimethyloctadecylammonium chloride. The binder was a 30% pozzolanic cement, 70% granulated blast furnace slag mixture. Several binder-to-bentonite ratios and different concentrations of the organics on the bentonite were used. Kinetics of hydration were studied by measurement of chemically bound water and by means of thermal and calorimetric analyses. Microstructure and other physico-mechanical properties of the solidified forms were studied by means of mercury intrusion porosimetry, scanning electron microscopy and unconfined compressive strength measurement. Leaching was checked by two different leaching tests: one dynamic, on monolithic samples, and the other static, on powdered samples. This study indicates that the incorporation of the organic-loaded bentonite in the binder matrix causes modifications in the hardened samples by altering cement hydration. The effects of the two organic contaminants are differentiated.

Adsorption↗

PubMed2001

Human mitochondrial DNA deletions associated with mutations in the gene encoding Twinkle, a phage T7 gene 4-like protein localized in mitochondria.

The gene products involved in mammalian mitochondrial DNA (mtDNA) maintenance and organization remain largely unknown. We report here a novel mitochondrial protein, Twinkle, with structural similarity to phage T7 gene 4 primase/helicase and other hexameric ring helicases. Twinkle colocalizes with mtDNA in mitochondrial nucleoids. Screening of the gene encoding Twinkle in individuals with autosomal dominant progressive external ophthalmoplegia (adPEO), associated with multiple mtDNA deletions, identified 11 different coding-region mutations co-segregating with the disorder in 12 adPEO pedigrees of various ethnic origins. The mutations cluster in a region of the protein proposed to be involved in subunit interactions. The function of Twinkle is inferred to be critical for lifetime maintenance of human mtDNA integrity.

Amino Acid Sequence↗

PubMed2001

A placebo-controlled, double-blind study of mesoglycan in the treatment of chronic venous ulcers.

OBJECTIVES: to assess the effect of treatment with mesoglycan, a sulphated polysaccharide compound, on the healing of venous ulcers. Design randomised, placebo-controlled, double-blind, multicentre trial. METHODS: non-diabetic outpatients with chronic venous insufficiency confirmed by duplex ultrasound, normal ankle/arm pressure index and presence of a leg ulcer were eligible. Patients were randomised to mesoglycan, 30 mg/day intramuscularly for 3 weeks followed by 100 mg/day orally, or matching placebo, as an adjunct to compression therapy and topical wound care. Treatment and observation were continued until complete ulcer healing or for 24+/-1 weeks. Time to ulcer healing and healing rates were estimated with the Kaplan-Meier method. RESULTS: One hundred and eighty-three patients were randomised and included in the analysis (92 mesoglycan, 91 placebo). Median ulcer area upon inclusion was 3.6 cm(2)in the mesoglycan group and 3.9 cm(2)in the placebo group. The estimated time to heal 75% of the patients was 90 days on mesoglycan versus 136 days on placebo, while the cumulative rate of healing by the end of observation was 97% versus 82%, respectively. The difference in favour of mesoglycan was statistically significant (p < 0.05, centre-stratified Cox's model). The relative risk of ulcer healing with mesoglycan was 1.48. The rate of adverse events was 7/92 on mesoglycan and 6/91 on placebo. CONCLUSIONS: treatment with mesoglycan in addition to established venous ulcer therapy resulted in a significantly faster and more frequent ulcer healing, and did not raise any safety concerns.

Chronic Disease↗