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2.
Gastroenterol Clin Biol ; 33(1 Pt 1): 88-91, 2009 Jan.
Artículo en Francés | MEDLINE | ID: mdl-18603394

RESUMEN

Sporadic colonic juvenile polyps are uncommon in adults. We report three cases for which clinical manifestations were presence of occult blood in the stool, rectal bleeding or chronic diarrhea. Two of these polyps occurred in the caecum which is an uncommon localisation. Endoscopic characteristics of these polyps were indistinguishable from adenomas. Endoscopic resection was complicated in one case by bleeding.


Asunto(s)
Pólipos del Colon/diagnóstico , Adulto , Anciano , Pólipos del Colon/cirugía , Diarrea/etiología , Endoscopía Gastrointestinal , Femenino , Hemorragia Gastrointestinal/etiología , Humanos , Masculino , Sangre Oculta , Recto
3.
Med Lav ; 98(1): 18-24, 2007.
Artículo en Italiano | MEDLINE | ID: mdl-17240641

RESUMEN

BACKGROUND: Wood dust exposure is strongly associated with the induction of cancer of the nasal cavity and paranasal sinuses (NSC), mainly among furniture production workers. Only limited information is available on wood dust exposure in other industrial sectors, including agriculture. NSC's are defined as "high occupational aetiology fraction" neoplasms, and are therefore indicated as sentinel tumours in occupational medicine. OBJECTIVES: The report concerns two cases of NSC that occurred in two poultry breeders and the investigations performed in order to define their occupational exposure. METHODS AND RESULTS: Epidemiological surveillance of NSC within the framework of routine activity of the Cancer Registry of the Province of Brescia (one million inhabitants) identified the two cases. Initially the first NSC case was considered as "probably exposed to formaldehyde" during shed tile disinfecting operations. After discovery of a similar case and further investigation in the sector formaldehyde exposure was found to be at a very low level. However, the observation that hard and soft wood dust was present, followed by dust monitoring, revealed a high level of exposure. The 23 personal and area air samples, performed in a turkey breeding shed, gave concentrations of between 1.3 and 2.3 mg/mc during low dust exposure jobs and concentrations of between 4 and 43.2 mg/mc during litter replacement (100% exceeded the ACGH TLV limit of 1 mg/cm and 25% were even above the legal limits (5 mg/mc according to Italian D.Lgs. 66/2000)). Since breeders are not aware of this type of risk and the use ofpersonal protection is not scrupulous, the local health and safety unit has started an information campaign for the entire work category as regards the necessity of controlling this cancer risk. The two cases of NSC described here were reported to the National Labour Insurance Institute (INAIL) for compensation. CONCLUSION: NSC epidemiological surveillance performed through a population registry proved to be of great use in the identification of cases among employees in similar sectors, and thus the identification of previously unknown wood dust exposures with consequent implementation of preventive measures.


Asunto(s)
Crianza de Animales Domésticos , Cavidad Nasal , Neoplasias Nasales/etiología , Enfermedades Profesionales/etiología , Neoplasias de los Senos Paranasales/etiología , Anciano , Animales , Humanos , Masculino , Persona de Mediana Edad , Aves de Corral , Factores de Riesgo
4.
Biophys J ; 89(2): 1353-61, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15951375

RESUMEN

We have previously shown that lamellar body-like particles, the form in which pulmonary surfactant is secreted, spontaneously disintegrate when they contact an air-liquid interface, eventually creating an interfacial film. Here, we combined these studies with a new technique enabling the simultaneous and non-invasive measurement of surface tension (gamma). This method is a refinement of the pendant-drop principle. A sapphire cone with a 300-microm aperture keeps the experimental fluid by virtue of surface coherence in a fixed and nearly planar position above the objective of an inverted microscope. The radius of curvature of the fluid meniscus is related to gamma and determines the pattern of light back-reflection upon epi-illumination. This method, which we name "inverted interface", has several novel aspects, in particular its microscopic dimensions. When using lamellar body-like particles freshly released by alveolar type II cells, we found that their conversion at the interface resulted in gamma-reduction close to 30 mN/m. After a fast initial decay, gamma-decrease proceeded slowly and in proportion to single particle conversions. These conversions ceased with time whereas gamma decreased further, probably due to reorganization of the already deposited material. The present investigation indicates that surface film formation by adsorption of large surfactant aggregates is an important mechanism by which gamma is reduced in the lung.


Asunto(s)
Pruebas de Dureza/instrumentación , Interpretación de Imagen Asistida por Computador/métodos , Microscopía Fluorescente/instrumentación , Alveolos Pulmonares/química , Surfactantes Pulmonares/química , Refractometría/instrumentación , Tensión Superficial , Animales , Células Cultivadas , Diseño de Equipo , Análisis de Falla de Equipo , Pruebas de Dureza/métodos , Microscopía Fluorescente/métodos , Alveolos Pulmonares/citología , Ratas , Ratas Sprague-Dawley , Refractometría/métodos
6.
Int J Biol Macromol ; 28(3): 219-26, 2001 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-11251229

RESUMEN

This paper reports isolation, structural characterization and some physico-chemical properties in aqueous solution of the exopolysaccharide (EPS) produced by Streptococcus thermophilus strain SFi20. The yield of the purified EPS was found to be reproducible and close to the average value of 143 mg/l. The chemical structure, previously suggested, has been confirmed on the basis of NMR data. Viscometric, chiro-optical and rheological measurements have been carried out with the aim of characterizing the conformational state of the polysaccharide in aqueous solution. All the data reported indicate that the EPS does not undergo a cooperative conformational transition under the investigated experimental conditions. Furthermore, the viscosity data and the viscoelastic behaviour suggest that the polymer is rather flexible and adopts a random coil conformation in aqueous solution.


Asunto(s)
Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/aislamiento & purificación , Streptococcus/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Dicroismo Circular , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Peso Molecular , Reología
7.
Ann Pathol ; 19(1): 23-5, 1999 Mar.
Artículo en Francés | MEDLINE | ID: mdl-10320907

RESUMEN

We report a case of intraneural perineurioma, developed in the left cubital nerve, in a five-year old girl. This intraneural tumor is rare and shows a typical histologic appearance: concentric whorls of perineurial cells EMA+, PS100-, around nerve fibers. This tumor must be distinguished from extraneural or soft tissue perineurioma, also composed of perineurial cells, with distinct clinical presentation and histological appearance.


Asunto(s)
Neoplasias de la Vaina del Nervio/patología , Neoplasias del Sistema Nervioso Periférico/patología , Preescolar , Femenino , Humanos
8.
Lung Cancer ; 22(2): 97-102, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10022217

RESUMEN

Several authors proposed the stage at diagnosis and some histopathological features as prognostic factors of bronchial carcinoids. However, since large tumour diameters or nodal metastases are frequently associated to aggressive histology, their prognostic role is unclear. To investigate the relationships between the clinicopathological parameters at diagnosis and outcome, 21 patients were analysed. Overall 26% of the radically resected patients recurred. Recurrences and disease-specific mortality were related to atypical histology and, only in cases with typical histology, to the presence of hilar or mediastinal lymph node metastases. These prognostic factors were valuable independently of the size of the primary tumour, that was remarkably homogeneous, always less than 3 cm, thus not predictive of recurrence. Moreover we evaluated the role of somatostatin receptor scintigraphy, a diagnostic tool only preliminary studied in this field. Scintigraphy with 111In-octreotide revealed the primary tumours at diagnosis (8/8), the increase in tumour size in two unresected patients, and all the cases of recurrent or metastatic disease (5/11), sometimes before the appearance of symptoms. These results suggest the usefulness of histology and nodal status as prognostic factors in clinical practice. Somatostatin receptor scintigraphy turns out to be a powerful diagnostic tool, for an accurate staging and an early diagnosis of recurrence in bronchial carcinoids.


Asunto(s)
Neoplasias de los Bronquios/diagnóstico por imagen , Neoplasias de los Bronquios/patología , Tumor Carcinoide/diagnóstico por imagen , Tumor Carcinoide/patología , Radioisótopos de Indio , Octreótido/análogos & derivados , Ácido Pentético/análogos & derivados , Adulto , Anciano , Neoplasias de los Bronquios/clasificación , Tumor Carcinoide/clasificación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Cintigrafía
9.
Biochim Biophys Acta ; 1336(2): 211-7, 1997 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-9305792

RESUMEN

A wild-type Acetobacter pasteurianus was subjected to chemical mutagenesis for the induction and isolation of a cellulose overproducing strain. A mutagenized strain capable of synthesizing double amounts of cellulose compared to the wild type was obtained. Cellulose, both from the wild-type and the mutagenized strain, was extracted and purified for chemical characterization and investigation of its physico-chemical properties. The comparison of the two microbial polysaccharides shows that the putative mutation of A. pasteurianus strain had no effect on some cellulose features such as chemical structure, polymorphic form, crystallinity.


Asunto(s)
Acetobacter/química , Celulosa/química , Acetobacter/metabolismo , Celulosa/biosíntesis , Celulosa/aislamiento & purificación , Mutación
11.
Q J Nucl Med ; 39(4 Suppl 1): 9-12, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9002741

RESUMEN

Chemodectoma is a rare, slow growing neoplasm with local aggressiveness and a high rate of residuals after surgery, arising from paraganglionic tissue (neural crest) and therefore able to take up Metaiodobenzylguanidine (MIBG). The aim of this study was to evaluate the diagnostic accuracy of 123I-MIBG Single Photon Emission Computed Tomography (SPECT) in comparison to Selective Digital Angiography (SDA), Computed Tomography (CT) and Magnetic Resonance Imaging (MRI). We studied 50 patients (41 women, 9 men) mean age 56 years (range 14-79), with diagnostic suspicion of chemodectoma (CH). There were 2 groups of patients: Group A (26 patients) examined before Surgery and Group B (24 patients) examined after surgery. SPECT of the head and neck region was performed 4 hours after i.v. administration of 185 MBq of 123I-MIBG. All patients were pre-treated with iodine solution. We performed a qualitative evaluation of the reconstructed slices. In Group A, all patients with CH (24) showed accumulation of MIBG in agreement with SDA, CT and MRI: 2 patients (histologically one had a cordoma, the other metastasis of papillary thyroid carcinoma), did not show any accumulation of 123I-MIBG. In Group B, 6 patients showed accumulation of 123I-MIBG in local residuals, and 9 were negative. Six patients with a lesion smaller than 1.5 cm were negative. Three patients had a positive scan but no lesion on SDA, CT and MRI. 123I-MIBG SPECT proved to be useful procedure in the diagnosis of untreated CH. During follow-up after surgery this procedure may assume a role in the perspective of radiometabolic therapy with 131I-MIBG.


Asunto(s)
Radioisótopos de Yodo , Yodobencenos , Paraganglioma Extraadrenal/diagnóstico por imagen , Radiofármacos , Tomografía Computarizada de Emisión de Fotón Único , 3-Yodobencilguanidina , Adolescente , Adulto , Anciano , Angiografía de Substracción Digital , Carcinoma Papilar/secundario , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Procesamiento de Imagen Asistido por Computador , Inyecciones Intravenosas , Radioisótopos de Yodo/administración & dosificación , Yodobencenos/administración & dosificación , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neoplasia Residual/diagnóstico por imagen , Neoplasia Residual/patología , Paraganglioma Extraadrenal/patología , Paraganglioma Extraadrenal/cirugía , Radiofármacos/administración & dosificación , Neoplasias de la Tiroides/patología , Tomografía Computarizada por Rayos X
12.
Int J Biol Macromol ; 17(3-4): 183-8, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7577816

RESUMEN

Conformational analysis of various forms of glucuronic acid dimers as the model structures of oxidized cellulose has been performed using molecular mechanics with a CVFF force field. The effects of ionization of carboxyl groups, ion pairing with explicit consideration of counter-ions (Na+, Mg2+) and the implicit inclusion of a solvent effect via the dielectric constant, epsilon, have been simulated. The non-ionized glucuronic acid dimer shows conformational behaviour similar to that of unoxidized cellobiose. The ionization of COOH groups leads to strong destabilization of C and D conformers (with both COO- groups on the same side of the molecule), while complexation with counter-ions leads to strong stabilization of these forms which yield highly wound low-pitch helices. An increase in the solvent polarity has an attenuating effect on the behaviour described above.


Asunto(s)
Celobiosa/química , Celulosa/química , Disacáridos/química , Modelos Moleculares , Aniones , Conformación de Carbohidratos , Secuencia de Carbohidratos , Glucuronatos , Ácido Glucurónico , Magnesio , Datos de Secuencia Molecular , Oxidación-Reducción , Sodio , Programas Informáticos , Solventes
16.
Eur J Nucl Med ; 19(3): 222-5, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1533370

RESUMEN

Abnormally high uptake of technetium-99m hexakis-2-methoxyisobutylisonitrile (99mTc-SESTAMIBI) in the right ventricle and in the septum was observed in a 47-year-old woman initially presenting with dysarthria and left hemiparesis. Endomyocardial biopsy demonstrated a high-grade malignant non-Hodgkin's lymphoma. Complete remission was achieved by combined cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) chemotherapy and radiotherapy of the heart and mediastinum. The post-remission single photon emission tomography (SPET) 99mTc-SESTAMIBI study showed a homogeneous distribution pattern, in agreement with echocardiography computed tomography and magnetic resonance imaging. Increased uptake of 99mTc-SESTAMIBI, a myocardial perfusion agent, has been observed in some benign and malignant tumours. It may prove to be useful in the diagnosis and follow-up of malignancies.


Asunto(s)
Neoplasias Cardíacas/diagnóstico por imagen , Linfoma no Hodgkin/diagnóstico por imagen , Compuestos de Organotecnecio , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Terapia Combinada , Ciclofosfamida/administración & dosificación , Doxorrubicina/administración & dosificación , Femenino , Neoplasias Cardíacas/tratamiento farmacológico , Neoplasias Cardíacas/radioterapia , Humanos , Linfoma no Hodgkin/tratamiento farmacológico , Linfoma no Hodgkin/radioterapia , Persona de Mediana Edad , Prednisona/administración & dosificación , Cintigrafía , Inducción de Remisión , Tecnecio Tc 99m Sestamibi , Vincristina/administración & dosificación
17.
Agressologie ; 31(5): 257-8, 1990 May.
Artículo en Francés | MEDLINE | ID: mdl-2288337

RESUMEN

Forty five patients suffering by S.A.H., with I-III degree according to Hunt-Hess classification, have been studied with SPECT, performed within 72 hours from the hemorrhage, in order to evaluate early alterations of cerebral blood flow and their prognostic value. The patients with a clinical worsening showed an important diminution of C.B.F. detected by SPECT and a great amount of blood in the sub-arachnoidal spaces at the CT scan (III degree, according to Fischer). If these results will be confirmed with further studies, it could be possible to early identify a group of patients with a high risk of developing a cerebral vasospasm.


Asunto(s)
Circulación Cerebrovascular , Hemorragia Subaracnoidea/diagnóstico por imagen , Tomografía Computarizada de Emisión de Fotón Único , Adulto , Enfermedades Arteriales Cerebrales/diagnóstico , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Riesgo , Espasmo/diagnóstico
18.
Int J Biol Macromol ; 12(2): 79-84, 1990 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2127696

RESUMEN

This paper reports on the chemical structure and on some physicochemical properties of a new exopolysaccharide, CC-EPS, secreted by a filamentous nitrogen-fixing cyanobacterium, Cyanospira capsulata. Solution properties of CC-EPS were studied with the aim of characterizing the conformational state of the polysaccharide in water and in aqueous salt solution, in view of the peculiar rheological properties. Because the molecule has two different uronic acid residues, a variation of pH and/or ionic strength was considered to be the best perturbation to disclose any possible ordered structures. We found no evidence for a cooperative conformational transition from the change of the chiro-optical properties or from the smooth increase of pKa as a function of the degree of ionization, alpha, of the polyacid. The same conclusion was drawn from the study of the temperature dependence and ionic strength dependence (in the range up to 0.1 M NaCl) of solution properties. The data suggest that the solution conformation of CC-EPS is a random coil with a chain flexibility comparable to that of alginate.


Asunto(s)
Cianobacterias/análisis , Polisacáridos/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Dicroismo Circular , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Concentración Osmolar , Temperatura , Viscosidad
19.
FEMS Microbiol Lett ; 53(1-2): 211-7, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2612887

RESUMEN

The pattern of polysaccharide production amongst strains of Rhizobium phaseoli appear very varied: some strains produce anionic exopolysaccharides (EPS) as major polysaccharides (EPS) as major polymer without any other product, but most strains exhibit greater polysaccharide diversity. Apart from EPS they excrete capsular polysaccharides (CPS) and accumulate poly-beta-hydroxybutyric acid (PHB) and/or glycogen in their cells. The latter can then be used as C-sources for further synthesis of EPS and CPS. Some strains are only very poor producers or do not produce at all. Nine strains of R. phaseoli have been analysed and shown to possess the K-36 type of polysaccharide (EPS), as do strains of R. leguminosarum (6 strains) and R. trifolii (9 strains). Three strains of R. phaseoli have been found to possess the K-87 type of polysaccharide and types K-38 and K-44 polysaccharides have only been found in their own type strains.


Asunto(s)
Polisacáridos Bacterianos/biosíntesis , Rhizobium/metabolismo , Conformación de Carbohidratos , Fenómenos Químicos , Química , Galactosa/análisis , Glucosa/análisis , Glucuronatos/análisis , Cinética , Polisacáridos Bacterianos/análisis , Piruvatos/análisis , Rhizobium/crecimiento & desarrollo
20.
Minerva Med ; 80(3): 215-26, 1989 Mar.
Artículo en Italiano | MEDLINE | ID: mdl-2717043

RESUMEN

To prevent delayed cardiomyopathy induced by adriamycin and subsequent severe congestive heart failure, a monitoring schedule with noninvasive techniques to measure cardiac performance (CPK-MB, electrocardiographic, systolic time intervals, echocardiography and quantitative radionuclide angiography) has been used. 15 patients, 33 to 65 years old, with metastatic breast carcinoma, previously treated with a polychemotherapy protocol not including adriamycin have been studied. Monitoring at 0 time allowed to exclude one patient with previous asymptomatic cardiomyopathy and to treat patients at risk with cardiovascular pathology, up to reach and even exceed the dosage of 550 mg/m2. Four of the treated patients showed positive findings of cardiomyopathy at different adriamycin dosage levels: 2 asymptomatic dilatative cardiomyopathies, 1 symptomatic and 1 with congestive heart failure remitted with medical therapy. No patient died because of cardiovascular complications. The results obtained show that of all noninvasive techniques used, only quantitative radionuclide angiocardiography allowed, when employed following an adequate monitoring schedule, to detect reliable findings of moderate and reversible cardiomyopathy thus indicating the appropriate time for drug discontinuation.


Asunto(s)
Cardiomiopatías/inducido químicamente , Doxorrubicina/efectos adversos , Adulto , Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/tratamiento farmacológico , Cardiomiopatías/diagnóstico , Cardiomiopatías/prevención & control , Terapia Combinada , Doxorrubicina/administración & dosificación , Femenino , Pruebas de Función Cardíaca , Humanos , Persona de Mediana Edad , Monitoreo Fisiológico/métodos , Metástasis de la Neoplasia
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