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G Guazzi

Publications and source records attributed to G Guazzi.

At least 19 recordsLinked to original sources
PubMed2006

Three-dimensional analysis of pulmonary nodules by MSCT with Advanced Lung Analysis (ALA1) software.

PURPOSE: The purpose of this study was to test the reproducibility of the three-dimensional (3D) Advanced Lung Analysis software (3D-ALA, GE Healthcare) in the estimation of pulmonary nodule volume. MATERIALS AND METHODS: We retrospectively reviewed the unenhanced multislice CT scans (Lightspeed Pro 16 GE) of 77 patients with a solitary pulmonary nodule (n=71) or metastatic pulmonary disease (n=6). A total of 103 pulmonary nodules (19 well-circumscribed, 45 juxtavascular and 39 juxtapleural) were analysed grouped into five classes based on diameter: <5 mm, 10 nodules (9.7%); >or=5 to <10 mm, 25 nodules (24.2%); >or=10 mm to <15 mm, 41 nodules (39.8%); >or=5 to <18 mm, 14 nodules (13.6% ); >or=8 to <30 mm, 13 nodules (12.62%). The following acquisition parameters were used: slice thickness 0.625 mm, reconstruction interval 0.4 mm, pitch 0.562:1, 140 kV, 300 mAs, field of view 13 cm, bone kernel. For each of the 103 nodules three, 3D volume measurements were obtained by the 3D-ALA software. The reproducibility of nodule segmentation was evaluated according to a visual score (1=optimal, >or=95%; 2=fair, 90-95%; 3=poor, 0.05). CONCLUSIONS: Three-dimensional volume measurement with ALARiassunto 1 software is reproducible for all nodules as regards dimension and site. ALA-1 software provided a good and reproducible volume measurement in well-circumscribed and most juxtavascular nodules. Volumetric evaluation and reproducibility of volume estimation in juxtapleural pulmonary nodules, particularly those adjacent to diaphragmatic pleura, is inadequate, and software improvement is needed.

Aged↗
PubMed2000

Type I sialidosis: a clinical, biochemical and neuroradiological study.

We report biochemical, morphological and neuroradiological findings in a 40-year-old woman affected with type I sialidosis. The clinical symptoms, consisting of a cerebellar syndrome, were first noted at the age of 17 years. The macular cherry-red spot was first observed after 23 years of disease. A CT scan performed at 21 years of age showed enlargement of the fourth ventricle. Nuclear magnetic resonance imaging of the brain performed at the age of 40 showed severe atrophy of the cerebellum and pontine region; atrophy of cerebral hemispheres and of the corpus callosum was also observed. We emphasize the prolonged course of illness in this patient, observed over a long period of time. Of particular interest is the neuroradiological study showing our findings both at the beginning of the disease and after 20 years.

Adult↗
PubMed2000

Autonomic nervous system and smooth muscle cell involvement in systemic sclerosis: ultrastructural study of 3 cases.

OBJECTIVE: To investigate morphological abnormalities in nerve and smooth muscle structures of the anorectal wall underlying gastrointestinal dysfunction in patients with systemic sclerosis (SSc). METHODS: We performed deep rectal biopsy in 3 patients with limited scleroderma of relatively recent onset and intestinal symptoms. RESULTS: We found ultrastructural signs of axonal degeneration and cytoskeletal abnormalities in the bundles of unmyelinated fibers. There was also focal degeneration of smooth muscle cells, often in association with the presence of partially degranulated mast cells. Many mast cells were also observed in close relation to nerve fibers and vessels. The enteric vessels often showed basal lamina reduplication and hypertrophied endothelial cells with obliterated lumen. No significant fibrosis was found. CONCLUSION: Our findings indicate early involvement of the autonomic nervous system and to a lesser extent of smooth muscle cells. We confirmed the presence of early vascular lesions and involvement of mast cells in the pathological process.

Adult↗
PubMed1999

Inheritance of a 38-kb fragment in apparently sporadic facioscapulohumeral muscular dystrophy.

Facioscapulohumeral dystrophy (FSHD) is an autosomal-dominant muscular disorder associated with a short (<35 kb) EcoRI/BlnI fragment resulting from deletion of an integral number of units of a 3.3-kb repeat located at 4q35. In this study, we determined fragment sizes separated by pulsed-field gel electrophoresis in a patient with an apparently sporadic case of FSHD and in his healthy family members. A 38-kb fragment was detected in the proband, in his older brother, and in their father. This finding prompted a clinical reevaluation of the father and brother. A subclinical phenotype restricted to abdominal muscle weakness was detected, and serum creatine kinase values were found to be elevated in both. The proband's brother also showed evidence of an independently occurring subtelomeric rearrangement of 4q35, which normally occurs in about 20% of the population. The identification of a "borderline" 38-kb EcoRI/BlnI fragment in an affected subject and his very mildly affected relatives extends the size range of disease alleles and expands existing data on the variable intrafamilial expressivity of FSHD. This study highlights the importance of a careful molecular and clinical analysis extended to family members of apparently sporadic cases with larger EcoRI/BlnI fragments for accurate diagnosis and appropriate genetic counseling in FSHD.

Adult↗
PubMed1998

CAG repeat expansion in an italian family with spinocerebellar ataxia type 2 (SCA2): a clinical and genetic study.

We report an Italian family in which molecular genetic analysis showed expansion of CAG repeats indicative of the SCA2 genotype. This family confirms that ataxia, ophthalmoparesis and sensory peripheral neuropathy are the salient features of the SCA2 phenotype. In the present cases, early onset and mental deterioration were important additional findings. Nerve biopsy findings were compatible with a chronic axonopathy. We found a direct correlation between length of triplet expansion and severity of the clinical symptoms. Of particular interest is the late-onset phenotypical expression in a patient with 34 repeats.

Adult↗
PubMed1997

Localization of the laminin alpha 2 chain in normal human skeletal muscle and peripheral nerve: an ultrastructural immunolabeling study.

A particular form of congenital muscular dystrophy is associated with a deficiency of the tissue-specific basement membrane protein laminin alpha 2. A more precise knowledge of the normal distribution and localization of laminin alpha 2 would be useful in further elucidating the development of this disorder. In this study we used specific electron microscopic techniques, i.e., thin-section fracture labeling and cryoultramicrotomy in combination with immunogold labeling for laminin alpha 2, to determine its ultrastructural localization in normal human muscle and peripheral nerve. Both in muscle and in peripheral nerve, laminin alpha 2 is found to be associated solely with the basal lamina of myofibers and Schwann cells, respectively. Of special interest is the finding that in peripheral nerve, laminin alpha 2 is associated only with myelinated and not with unmyelinated nerve fibers.

Humans↗
PubMed1997

High levels of cerebrospinal fluid IgM binding to myelin basic protein are associated with early benign course in multiple sclerosis.

We assessed human myelin basic protein (MBP) binding IgM levels in CSF. MBP is the most studied putative antigen in multiple sclerosis (MS) and immune responses against it may be involved in the demyelination process. We also correlated these levels with EDSS score and other parameters of disease progression and prognosis, both at the time of CSF analysis and during follow-up. CSF IgM anti-MBP levels were assayed by measuring total IgM levels with solid-phase ELISA in CSF samples from 66 patients with relapsing-remitting MS, 11 subjects without neurological diseases, 20 patients with non-inflammatory neurological diseases and 7 patients with lymphocytic meningitis, before and after immunoabsorption with human MBP. Confirmation of IgM binding specificity was performed by immunoblotting of positive CSF samples onto MBP coated-nitrocellulose sheets. Clinical evaluation (disability score, number and time of attacks) was performed during a mean follow-up of 2.7 +/- 1.1 years. 23 of the 66 relapsing-remitting MS patients (33.8%) had elevated IgM anti-MBP levels. In this patient subgroup, IgM anti-MBP levels correlated with the IgM index (r = 0.71; P = 0.0001), but not with CSF/serum albumin (r = 0.08; P = 0.72). In the first year of follow-up, patients with low IgM anti-MBP suffered from more numerous attacks than those with elevated levels (0.86 +/- 0.63 versus 0.43 +/- 0.58; P = 0.017). Patients with high IgM binding to MBP had a first attack during follow-up in a significantly higher time than those with low binding (28.87 +/- 4.7 versus 17 +/- 2.6 months, respectively; P = 0.005) and reached a decrease of 0.5 EDSS point significantly faster than those with low IgM (16.17 +/- 1.2 versus 29.7 +/- 2.6 months, respectively; P = 0.0002). A similar significant finding was observed when the time to reach low disability score (EDSS < or = 2.0) was analyzed (10.7 +/- 2.57 +/- 3.3 months, respectively; P = 0.014). These findings demonstrate that in a subgroup of MS patients, elevated CSF levels of IgM anti-MBP are associated with early favorable course and therefore suggest that IgM binding to MBP could be a possible prognostic marker in relapsing-remitting MS to select early MS patients for future trials.

Adolescent↗
PubMed1997

[Role of Doppler color in the differential diagnosis of benign and malignant adenopathies].

The diagnosis of enlarged lymph nodes is of the utmost importance especially in the treatment planning of cancer patients. US yields such morphological findings as node size, longitudinal/transverse diameter ratio, hilum visibility and cortical thickness, which however do not permit the differential diagnosis of benign from malignant forms. Some authors tried to distinguish inflammatory enlargement from metastatic forms on the basis of color Doppler findings, with conflicting and questionable results. We investigated the potentials of color Doppler US in the differential diagnosis of benign and malignant lymph node enlargement using morphological data and flow measurements in lymphatic hilum vessels. The palpable superficial lymph nodes of 70 patients were studied with color Doppler with a linear probe (7.5-10 MHz) equipped for Doppler flow measurements. The largest lymph node was studied in multiple enlargement. The final diagnosis was made with US-guided cytology and/or excisional biopsy. The venous hilar vessels were depicted with color Doppler US in 44/45 patients with lymphadenitis and only in 1/17 patients with metastatic enlargement. Spectral Doppler exams of the hilar arteries showed flows with a wide telediastolic component in lymphadenitis (relative RI:0.58), while flow was rapid and with poor telediastolic component (relative RI:0.84) in metastatic enlargement. Average RI was 0.62 in Hodgkin's lymphomas and 0.71 in all the other lesions. We conclude that the distortion and compression of the main hilar vessels in metastatic lymph node enlargement often prevents color Doppler depiction of venous vessels. Moreover, the compression and distortion of the intranodal capillary network (the "mass" effect) often results in increased RI, as detected with power Doppler in the lymphatic hilum. Even though color Doppler US studies of the hemodynamic changes in the hilar vessels need further validation in larger series of cases, our preliminary results suggest interesting potentials in distinguishing inflammatory from metastatic enlargement, which differentiation remains nevertheless difficult especially in Hodgkin's lymphoma.

Adolescent↗
PubMed1997

[High-resolution ultrasonography in the study of carpal tunnel syndrome].

We investigated the reliability of some US signs in the diagnosis of the carpal tunnel syndrome. We carried out a single-blind study with 13-MHz high resolution probes and electromyography on 132 patients with clinical evidence of the carpal tunnel syndrome; a control group of 20 asymptomatic patients was also submitted to US. Eighty-six of 107 patients with US signs of the carpal tunnel syndrome were then submitted to surgical decompression (resection of the transverse carpal ligament), while the extant 21 patients underwent conservative treatment and clinical follow-up. To diagnose the carpal tunnel syndrome, we considered the following US patterns: median nerve changes (swelling before its entrance into the carpal tunnel and flattening in the tunnel itself), palmar bowing of the flexor retinaculum, thickening of the transverse carpal ligament and increased depth of the carpal tunnel, as measured from the apex of the transverse carpal ligament convexity to the underlying carpal bone. Median nerve changes were unreliable signs and were missing in many cases: only 45 of 107 patients exhibited median nerve swelling before and/or its flattening in the carpal tunnel (42%). Such indirect signs as the thickening of the transverse carpal ligament in chronic cases were demonstrated in 94 of 107 patients with the carpal tunnel syndrome (88%) and canal deepening in all unilateral carpal tunnel syndromes was shown in 92 of 107 patients (87%); both these signs proved to be much more reliable. The palmar bowing of the flexor retinaculum was also difficult to demonstrate in surgical patients or in those with connective tissue fibrosis within the tunnel: this sign was demonstrated in 80 of 107 patients with the carpal tunnel syndrome confirmed with electromyography (75%). Tanzer and Rietze reported median nerve changes observed at surgery in 43% and 66% of their patients, respectively. Recent MR findings in asymptomatic wrists have demonstrated that the normal median nerve has an elliptical shape inside the carpal tunnel. To conclude, high resolution US exhibited 96% sensitivity, 95% specificity and 93% diagnostic accuracy and proved to play a major role in the diagnosis of the carpal tunnel syndrome.

Carpal Tunnel Syndrome↗
PubMed1996

Autosomal dominant limb girdle myopathy with ragged-red fibers and cardiomyopathy. A pedigree study by in vivo 31P-MR spectroscopy indicating a multisystem mitochondrial defect.

We describe a late-onset autosomal dominant limb girdle myopathy, associated with dilated cardiomyopathy and mental deterioration. In two affected members of the pedigree with histochemical (ragged-red and cytocrome c oxidase - negative fibers) and ultrastructural abnormalities of muscle mitochondria, in vivo muscle phosphorus MR spectroscopy disclosed a slow rate of phosphocreatine resynthesis after exercise. Brain phosphorus MR spectroscopy revealed a defect of the energy metabolism in the two patients and in a third asymptomatic member, as shown by a significantly low phosphocreatine, increased ADP and decreased phosphorylation potential. Molecular analysis of muscle mitochondrial DNA failed to reveal any known mutation, including multiple deletions of the mtDNA which have been associated with some autosomal dominant mitochondrial diseases. The multisystem clinical involvement, the presence of ragged-red fibers and the alterations revealed by in vivo brain and muscle 31P-MRS suggest that this limb-girdle syndrome represents an unusual phenotype of mitochondrial cytopathy.

Adult↗
PubMed1996

Muscular dystrophy, mental retardation and cardiomyopathy not associated with dystrophin deficiency.

We report on a male patient aged 38, affected by a syndrome whose characteristic features include onset in early childhood, slow progression, diffuse muscle weakness, mental retardation and cardiomyopathy. Muscle biopsy showed myopathic changes compatible with muscular dystrophy. However, immunostaining for dystrophin as well as 50 and 43 kDa dystrophin-associated glycoproteins (DAGs) was normal. Genetic analysis suggested that direct involvement of the dystrophin gene was highly unlikely. No other family members were affected. Although the clinical picture is reminiscent of Duchenne/Becker muscular dystrophy, the immunologically and genetically documented lack of dystrophin involvement suggests that this particular syndrome is as yet undescribed.

Adult↗
PubMed1996

The A to G transition at nt 3243 of the mitochondrial tRNALeu(UUR) may cause an MERRF syndrome.

OBJECTIVE: To verify the phenotype to genotype correlations of mitochondrial DNA (mtDNA) related disorders in an atypical maternally inherited encephalomyopathy. METHODS: Neuroradiological, morphological, biochemical, and molecular genetic analyses were performed on the affected members of a pedigree harbouring the heteroplasmic A to G transition at nucleotide 3243 of the mitochondrial tRNALeu(UUR), which is usually associated with the syndrome of mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS). RESULTS: The proband was affected by a fullblown syndrome of myoclonic epilepsy with ragged red fibres (MERRF), severe brain atrophy, and basal ganglia calcifications, without the MRI T2 hyperintense focal lesions which are pathognomonic of MELAS. Oligosymptomatic relatives were variably affected by lipomas, goitre, brain atrophy, and basal ganglia calcifications. Muscle biopsies in the proband and his mother showed a MELAS-like pattern with cytochrome c oxidase hyperreactive ragged red fibres and strongly succinate dehydrogenase reactive vessels. Quantification of the A3243G mutation disclosed 78% and 70% of mutated mtDNA in the muscle of the severely affected proband and of his oligosymptomatic mother respectively. Nucleotide sequencing of the mitochondrial tRNALeu(UUR) and tRNALys in the proband's muscle failed to show any additional nucleotide change which could account for the clinical oddity of this pedigree by modulating the expression of the primary pathogenic mutation. CONCLUSION: So far, MERRF has been associated with mutations of the mitochondrial tRNALys, and MELAS with mutations of the mitochondrial tRNALeu(UUR). Now MERRF may also be considered among the clinical syndromes associated with the A to G transition at nt 3243 of the tRNALeu(UUR).

Adolescent↗
PubMed1996

[Interstitial photocoagulation with laser in the treatment of liver metastasis].

Interstitial laser photocoagulation (ILP) causes tumor necrosis with local hyperthermia produced by laser light energy. We treated with US-guided ILP 14 patients (7 men and 7 women; mean age: 67 years) and 20 metastases: 9 of them were < 3 cm in max. diameter and 11 were > 3 cm (mean diameter: 2.9 cm); 14 metastases were from colon carcinoma, 5 from breast cancer and 1 from lung cancer. ILP was performed with 300 and 600 microns quartz fiberoptic guides advanced in 21-18G Chiba needles and a continuous-wave Nd: YAG laser with 1064 nm wavelength. We used single expositions of 5-6 minutes with an irradiation power of 5 watts and scheduled 3 treatment sessions, performing CT scans and biopsies at the end of each session. The extent of induced necrosis was classified as follows on the basis of CT findings: grade 1 = 100% necrosis; grade 2 = necrosis > 50%; grade 3 = necrosis < 50%. The average follow-up was 6 months. After the 3 scheduled treatment sessions, CT showed grade 1 necrosis in all the lesions < 3 cm in diameter and in 4/9 (44%) lesions > 3 cm and grade 2 and 3 necrosis in the remaining cases (necrosis > 50% in 95% of the lesions and 92% of the patients). The cytologic findings were in agreement with CT results in all grade 2 and 3 cases, but in one grade 1 necrosis cytology showed residual viable tumor. To conclude, ILP is a safe and well-tolerated procedure. Maximum efficacy was observed in the lesions < 3 cm, while lesion volume was markedly reduced in the lesions > 3 cm. US is a useful tool in the real-time monitoring of this procedure and CT is the most accurate imaging technique to assess treatment efficacy.

Aged↗
PubMed1994

Ataxia, mental deterioration, epilepsy in a family with dominant enamel hypoplasia: a variant of Kohlschütter-Tönz syndrome?

We describe 3 sibs, their father, and paternal grandfather with amelogenesis imperfecta. In 2 sibs and the father the defect is associated with a neurological syndrome which has a wide range of phenotypic variability. The proposita has ataxia, EEG abnormalities, moderate dementia, and enamel hypoplasia. This case and the affected relatives are discussed in relation to Kohlschütter-Tönz syndrome and neuroectodermal diseases. The syndrome described here, characterized by the association of a genetic enamel defect and neurological impairment, may be of considerable interest in advancing genetic and clinical knowledge on ectodermal tissues and their development.

Abnormalities, Multiple↗
PubMed1994

Atypical McLeod syndrome manifested as X-linked chorea-acanthocytosis, neuromyopathy and dilated cardiomyopathy: report of a family.

We report a family with three members affected by a typically X-linked McLeod syndrome. In the proband a very weak positivity for antigens of the Kell group was detected. His sister showed a normal antigenic pattern. We emphasize the prominent neurological picture characterized by a choreic syndrome with atrophy of the caudate nucleus on MRI, psychiatric disturbances, peripheral nerve and muscle biopsy findings indicating slight neuromuscular involvement, and cardiac abnormalities. The differential diagnosis is discussed.

Aged↗