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1.
J Endocrinol Invest ; 43(5): 575-585, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31797309

RESUMEN

BACKGROUND: Sellar melanocytomas represent a small subgroup of primary melanocytic tumors. They arise from melanocytes located in the meningeal lining of the sellar floor or in the diaphragma sellae and this location is very uncommon. Usually, sellar melanocytomas are benign and slow-growing tumors with a high likelihood of recurrence. PURPOSE: To our knowledge, due to the rarity of this condition, there are no guidelines regarding their diagnosis and treatment in the medical literature to date. We have developed a narrative review, analyzing the available studies regarding primary sellar melanocytomas reported in the medical literature. We have found ten papers on this topic and all of them are case reports. In all patients, tumor diagnosis was performed after the occurrence of neurological symptoms, in particular progressive visual loss or endocrinological disorders. The diagnosis is difficult, and it requires several preoperative and postoperative investigations, but histological examination is crucial. CONCLUSIONS: Transsphenoidal surgery is the first-choice treatment. In case of tumor's recurrence or regrowth, the role of radiation therapy and chemotherapy is not entirely clear.


Asunto(s)
Melanocitos/patología , Hipófisis/patología , Neoplasias Hipofisarias/patología , Humanos , Hipófisis/cirugía , Neoplasias Hipofisarias/cirugía
2.
J Pharm Biomed Anal ; 169: 260-268, 2019 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-30884324

RESUMEN

An integrated chromatographic system was developed to rapidly investigate the biocatalytic properties of ω-transaminases useful for the synthesis of chiral amines. ATA-117, an (R)-selective ω-transaminase was selected as a proof of concept. The enzyme was purified and covalently immobilized on an epoxy monolithic silica support to create an immobilized enzyme reactor (IMER). Reactor efficiency was evaluated in the conversion of a model substrate. The IMER was coupled through a switching valve to an achiral analytical column for separation and quantitation of the transamination products. The best conditions of the transaminase-catalyzed bioconversion were optimized by a design of experiments (DoE) approach. The production of (R)-1-(4-methoxyphenyl)propan-2-amine and (R)-1-methyl-3-phenylpropylamine, intermediates for the synthesis of the bronchodilator formoterol and the antihypertensive dilevalol respectively, was achieved in the presence of different amino donors. The enantiomeric excess (ee) was determined off-line by developing a derivatization procedure using Nα-(2,4-dinitro-5-fluorophenyl)-L-alaninamide reagent. The most satisfactory conversion yields were 60% for (R)-1-(4-methoxyphenyl)propan-2-amine and 29% for (R)-1-methyl-3-phenylpropylamine, using isopropylamine as amino donor. The enantiomeric excess of the reactions were 84%R and 99%R, respectively.


Asunto(s)
Cromatografía/métodos , Enzimas Inmovilizadas/química , Transaminasas/química , Aminación/fisiología , Aminas/química , Biocatálisis , Catálisis , Propilaminas/química , Estereoisomerismo
3.
Acta Otorhinolaryngol Ital ; 37(4): 281-285, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28663599

RESUMEN

Cocaine abuse occasionally causes extensive destruction of the osteocartilaginous structures of the nose, sinuses and palate, which mimics the clinical picture of other diseases associated with necrotising midfacial lesions. The differentiation of cocaine-induced midline destructive lesions (CIMDL) and limited granulomatosis with polyangiitis (GPA) may be difficult, particularly if patients do not readily admit substance abuse. We studied 10 patients with CIMDL and palate perforation referred to our Unit between 2002 and 2015. All cases underwent nasal endoscopy, sinus CT or MRI and ANCA test. In 8 patients, a nasal biopsy was performed. The PubMed database was searched to review all cases of palate perforation described in patients affected by CIMDL or GPA. All 10 cases presented with septal perforation and inferior turbinate destruction. We found hard palate perforation in 7 patients, soft palate perforation in 2 patients, and perforation of both in one patient. ANCA testing was negative in 8 patients and positive in 2, with C-ANCA and P-ANCA specificity, respectively. A review of the English literature identified palate perforation in 5 patients with GPA and in 73 patients with CIMDL. The presence of palate perforation in patients with MDL may represent a clinical marker that strongly favors CIMDL over GPA.


Asunto(s)
Trastornos Relacionados con Cocaína/complicaciones , Granulomatosis con Poliangitis/complicaciones , Enfermedades de la Boca/etiología , Hueso Paladar , Perforación Espontánea/etiología , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades de la Boca/diagnóstico , Estudios Retrospectivos , Perforación Espontánea/diagnóstico
4.
Eur J Endocrinol ; 176(5): 543-553, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28179449

RESUMEN

OBJECTIVE: Glucose-dependent insulinotropic polypeptide receptor (GIPR) overexpression has been recently described in a proportion of gsp- somatotropinomas and suggested to be associated with the paradoxical increase of GH (GH-PI) during an oral glucose load. DESIGN AND METHODS: This study was aimed at linking the GIP/GIPR pathway to GH secretion in 25 somatotropinomas-derived primary cultures and correlating molecular with clinical features in acromegalic patients. Given the impairment of the GIP/GIPR axis in acromegaly, an additional aim was to assess the effect of GH/IGF-1 stimulation on GIP expression in the enteroendocrine cell line STC-1. RESULTS: Nearly 80% of GIPR-expressing somatotropinomas, all of them negative for gsp mutations, show increased GH secretion upon GIP stimulation, higher sensitivity to Forskolin but not to somatostatin analogs. Besides increased frequency of GH-PI, GIPR overexpression does not appear to affect acromegalic patients' clinical features. In STC-1 cells transfected with GIP promoter-driven luciferase vector, IGF-1 but not GH induced dose-dependent increase in luciferase activity. CONCLUSIONS: We demonstrate that GIPR mediates the GH-PI in a significant proportion of gsp- acromegalic patients. In these cases, the stimulatory effect of IGF-1 on GIP promoter support the hypothesis of a functional GH/IGF-1/GIP axis. Further studies based on larger cohorts and the development of a stable transgenic model with inducible GIPR overexpression targeted to pituitary somatotroph lineage will be mandatory to establish the real role of GIPR in the pathogenesis of somatotropinomas.


Asunto(s)
Polipéptido Inhibidor Gástrico/genética , Polipéptido Inhibidor Gástrico/metabolismo , Adenoma Hipofisario Secretor de Hormona del Crecimiento/genética , Adenoma Hipofisario Secretor de Hormona del Crecimiento/metabolismo , Hormona de Crecimiento Humana/metabolismo , Neoplasias Hipofisarias/genética , Neoplasias Hipofisarias/metabolismo , Receptores de la Hormona Gastrointestinal/genética , Receptores de la Hormona Gastrointestinal/metabolismo , Acromegalia/genética , Acromegalia/metabolismo , Adolescente , Adulto , Anciano , Línea Celular , Linaje de la Célula/genética , Colforsina/farmacología , ADN/genética , Femenino , Humanos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Persona de Mediana Edad , Cultivo Primario de Células , Regiones Promotoras Genéticas/genética , Adulto Joven
5.
Crit Rev Oncol Hematol ; 88(3): 564-72, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23953683

RESUMEN

BACKGROUND: Extraneural dissemination of oligodendroglioma is rare. Cases of breast metastases have never been described in the literature. CASE REPORTS: We report the first two cases of young women with initial diagnosis of anaplastic oligodendroglioma who experienced mammary gland metastases and a review of the literature. RESULTS: Immunohistochemical analysis performed on material from both primary and metastatic sites did not allow to draw any conclusion on possible etiopathogenetic hypothesis. A review of literature yielded 35 cases of extracranial metastatic oligodendroglioma from 1989 to 2012. CONCLUSION: Though rare, extracranial dissemination from oligodendroglioma may occur not only in long surviving heavily pre-treated patients. The review of literature and these two cases suggest that spread is primarily to bone and then from bone to other organs through hematogenous route mostly due to leptomeningeal or dura mater invasion. Chemotherapy regimens similar to those commonly used for non metastatic oligodendroglioma are recommended for patients with good performance status.


Asunto(s)
Neoplasias Encefálicas/patología , Neoplasias de la Mama/secundario , Oligodendroglioma/patología , Adulto , Biopsia , Neoplasias Encefálicas/diagnóstico , Neoplasias de la Mama/diagnóstico , Femenino , Humanos , Angiografía por Resonancia Magnética , Clasificación del Tumor , Neovascularización Patológica/diagnóstico , Oligodendroglioma/diagnóstico
6.
Br J Neurosurg ; 27(3): 316-20, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23163297

RESUMEN

Cerebellopontine angle (CPA) medulloblastomas (MB) are rare lesions with few cases previously described in the literature. We report two further cases of CPA MB. The patients were a 22-year-old man and a 26-year-old woman with a mass developing in the CPA. The preoperative radiological diagnosis was vestibular schwannoma in the first case and petrosal meningioma in the second case. The patients were operated on through a retrosigmoid approach. The intraoperative findings revealed an intra-axial tumour and the histological diagnosis was classic type of MB in both cases. We review the literature and discuss pathological and radiological features and possible pathogenesis of CPA MB, underlining the necessity to consider MB in the differential diagnosis of CPA lesions.


Asunto(s)
Neoplasias Cerebelosas/diagnóstico , Ángulo Pontocerebeloso , Meduloblastoma/diagnóstico , Adulto , Neoplasias Cerebelosas/cirugía , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Meduloblastoma/cirugía , Tomografía Computarizada por Rayos X , Adulto Joven
7.
Biochemistry ; 50(30): 6549-58, 2011 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-21707079

RESUMEN

Uridine phosphorylase (UP), a key enzyme in the pyrimidine salvage pathway, catalyzes the reversible phosphorolysis of uridine or 2'-deoxyuridine to uracil and ribose 1-phosphate or 2'-deoxyribose 1-phosphate. This enzyme belongs to the nucleoside phosphorylase I superfamily whose members show diverse specificity for nucleoside substrates. Phylogenetic analysis shows Streptococcus pyogenes uridine phosphorylase (SpUP) is found in a distinct branch of the pyrimidine subfamily of nucleoside phosphorylases. To further characterize SpUP, we determined the crystal structure in complex with the products, ribose 1-phosphate and uracil, at 1.8 Å resolution. Like Escherichia coli UP (EcUP), the biological unit of SpUP is a hexamer with an α/ß monomeric fold. A novel feature of the active site is the presence of His169, which structurally aligns with Arg168 of the EcUP structure. A second active site residue, Lys162, is not present in previously determined UP structures and interacts with O2 of uracil. Biochemical studies of wild-type SpUP showed that its substrate specificity is similar to that of EcUP, while EcUP is ∼7-fold more efficient than SpUP. Biochemical studies of SpUP mutants showed that mutations of His169 reduced activity, while mutation of Lys162 abolished all activity, suggesting that the negative charge in the transition state resides mostly on uracil O2. This is in contrast to EcUP for which transition state stabilization occurs mostly at O4.


Asunto(s)
Proteínas Bacterianas/química , Familia de Multigenes , Streptococcus pyogenes/enzimología , Uridina Fosforilasa/química , Proteínas Bacterianas/genética , Catálisis , Dominio Catalítico/genética , Cristalografía por Rayos X , Mutagénesis Sitio-Dirigida , Pliegue de Proteína , Ribosamonofosfatos/química , Electricidad Estática , Especificidad por Sustrato/genética , Uracilo/química , Uridina Fosforilasa/genética
8.
J Neuroendocrinol ; 23(7): 641-9, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21554434

RESUMEN

Somatic mutations in the GNAS1 gene, encoding the α-subunit of the heterotrimeric stimulatory G protein (Gαs), occur in approximately 40% of growth hormone (GH)-secreting pituitary tumours. By altering the adenylate cyclase-cAMP-protein kinase A pathway, they unequivocally give somatotroph cells a growth advantage. Hence, the pathogenesis of somatotropinomas could be linked to anomalies in receptors coupled to the cAMP second-messenger cascade. Among them, the glucose-dependent insulinotropic polypeptide receptor (GIPR) is already known to play a primary role in the impaired cAMP-dependent cortisol secretion in patients affected by food-dependent Cushing's syndrome. In the present study, 43 somatotropinomas and 12 normal pituitary glands were investigated for GIPR expression by quantitative reverse transcriptase-polymerase chain reaction, western blotting and immunohistochemistry. Tumoural specimens were also evaluated for GNAS1 mutational status. The effect of GIPR overexpression on cAMP levels and GH transcription was evaluated in an in vitro model of somatotropinomas, the GH-secreting pituitary cell line GH3. GIPR was expressed at higher levels compared to normal pituitaries in 13 GNAS1 mutation-negative somatotropinomas. GIP stimulated adenylyl cyclase and GH-promoter activity in GIPR-transfected GH3 cells, confirming a correct coupling of GIPR to Gαs. In a proportion of acromegalic patients, GIPR overexpression appeared to be associated with a paradoxical increase in GH after an oral glucose tolerance test. Whether GIPR overexpression in acromegalic patients may be associated with this paradoxical response or more generally involved in the pathogenesis of acromegaly, as suggested by the mutually exclusive high GIPR levels and GNAS1 mutations, remains an open question.


Asunto(s)
Adenoma/genética , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Adenoma Hipofisario Secretor de Hormona del Crecimiento/genética , Hormona de Crecimiento Humana/genética , Regiones Promotoras Genéticas/fisiología , Receptores de la Hormona Gastrointestinal/genética , Somatotrofos/metabolismo , Acromegalia/complicaciones , Acromegalia/genética , Acromegalia/metabolismo , Adenoma/complicaciones , Adenoma/metabolismo , Adenoma/patología , Adulto , Animales , Células Cultivadas , Cromograninas , Análisis Mutacional de ADN , Femenino , Regulación Neoplásica de la Expresión Génica , Adenoma Hipofisario Secretor de Hormona del Crecimiento/complicaciones , Adenoma Hipofisario Secretor de Hormona del Crecimiento/metabolismo , Adenoma Hipofisario Secretor de Hormona del Crecimiento/patología , Hormona de Crecimiento Humana/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Mutación/fisiología , Ratas , Receptores de la Hormona Gastrointestinal/metabolismo , Regulación hacia Arriba/genética
9.
Nucleosides Nucleotides Nucleic Acids ; 29(4-6): 445-8, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20544534

RESUMEN

Four Clostridium perfringens phosphorylases were subcloned, overexpressed and analyzed for their substrate specificity. DeoD(1) and PunA could use a variety of purine substrates, including an antiviral drug 2',3'-dideoxyinosine (ddI). In one-pot synthesis using Clostridium phosphorylases, 2',3'-dideoxyuridine and hypoxanthine were converted to ddI at yield of about 30%.


Asunto(s)
Clostridium perfringens/enzimología , Didanosina/metabolismo , Pentosiltransferasa/metabolismo , Cromatografía Líquida de Alta Presión , Didanosina/síntesis química
10.
Minerva Endocrinol ; 32(3): 231-6, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17912159

RESUMEN

Pituitary carcinomas are very rare tumors, nearly always presenting as widely invasive masses, although the hallmark of these lesions is the finding of distant metastases. One third of reported cases are prolactin (PRL)-secreting tumors. We report the case of a fatal pituitary carcinoma evolving within 4 years from a PRL-secreting microadenoma. A 22-year-old woman presented because of galactorrhea. Evaluation of the patient disclosed slight hyperprolactinemia and magnetic resonance imaging (MRI) showed a 7-mm intrapituitary lesion, which responded to treatment with cabergoline. About 4 years after the first evaluation she developed sudden headache, ptosis, and diplopia in the right eye. MRI disclosed the growth of a large pituitary mass, invading the right cavernous sinus. Despite two trans-sphenoidal surgical procedures followed by gamma-knife radiosurgery, the patient showed rapid local progression of the tumor and the occurrence of new lung lesions, probably of metastatic nature. The patient died 7 months after the development of her first neurological symptoms because of tumor apoplexy and subsequent subarachnoid hemorrhage. This case represents the first documented rapid evolution from a microprolactinoma initially responding to dopamine agonists to a fatal pituitary carcinoma.


Asunto(s)
Carcinoma/patología , Neoplasias Hipofisarias/patología , Prolactinoma/patología , Adulto , Cabergolina , Terapia Combinada , Progresión de la Enfermedad , Agonistas de Dopamina/uso terapéutico , Resistencia a Medicamentos , Ergolinas/uso terapéutico , Resultado Fatal , Femenino , Humanos , Octreótido/uso terapéutico , Apoplejia Hipofisaria/etiología , Neoplasias Hipofisarias/complicaciones , Neoplasias Hipofisarias/tratamiento farmacológico , Neoplasias Hipofisarias/radioterapia , Neoplasias Hipofisarias/cirugía , Prolactinoma/complicaciones , Prolactinoma/tratamiento farmacológico , Prolactinoma/radioterapia , Prolactinoma/cirugía , Radiocirugia , Hemorragia Subaracnoidea/etiología
11.
Br J Haematol ; 138(3): 316-23, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17555470

RESUMEN

Well-established histopathological prognostic factors are lacking in primary central nervous system (CNS) lymphomas (PCNSL). The present study investigated the presence and prognostic role of tumour necrosis (TN) and reactive perivascular T-cell infiltrate (RPVI), defined as a rim of small reactive T-lymphocytes occurring alone or located between the vascular wall and large neoplastic cells, in tumour samples from 100 immunocompetent patients with PCNSL. World Health Organization histotypes of the patients were: 96 diffuse large B-cell lymphomas, two Burkitt-like lymphomas, one anaplastic large T-cell lymphoma and one unclassified B-cell lymphoma. TN was observed in 24 (24%) cases and RPVI in 26 (36%) of 73 assessable cases. Patients with RPVI-positive lesions exhibited a significantly better overall survival (OS) than patients with RPVI-negative lymphoma, particularly among patients treated with high-dose methotrexate-based chemotherapy (3-year OS: 59 +/- 14% vs. 42 +/- 9%, P = 0.02). By contrast, the presence of TN did not demonstrate prognostic significance. Multivariate analysis confirmed an independent association between RPVI and survival. In conclusion, the presence of RPVI is independently associated with survival in PCNSL. This parameter can be easily and routinely assessed at diagnosis on histopathological specimens.


Asunto(s)
Neoplasias del Sistema Nervioso Central/inmunología , Linfoma de Células B/inmunología , Linfocitos T/patología , Adulto , Anciano , Linfocitos B/patología , Vasos Sanguíneos , Neoplasias del Sistema Nervioso Central/mortalidad , Femenino , Humanos , Activación de Linfocitos , Linfoma de Células B/mortalidad , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pericitos/patología , Pronóstico , Tasa de Supervivencia
12.
Acta Neurochir (Wien) ; 148(12): 1311-4; discussion 1314, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17039304

RESUMEN

Intrasellar paragangliomas are very rare lesions with only six previous cases described in the literature. We present a further case of intrasellar paraganglioma. The patient was a 52 yr-old man who developed two transient ischemic attacks. A CT scan showed an intra- and supra-sellar expanding lesion, which was regarded as a possible non-functioning pituitary macro-adenoma. Removal of the lesion was accomplished by transsphenoidal surgery. Histological examination was diagnostic of a paraganglioma. We review the literature and discuss pathological features and possible pathogenesis of sellar and parasellar paragangliomas, underlining the necessity to consider paraganglioma in the differential diagnosis of sellar lesions.


Asunto(s)
Paraganglioma/patología , Hipófisis/patología , Neoplasias Hipofisarias/patología , Silla Turca/patología , Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/metabolismo , Diagnóstico Diferencial , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Proteínas del Tejido Nervioso/análisis , Proteínas del Tejido Nervioso/metabolismo , Procedimientos Neuroquirúrgicos , Paraganglioma/diagnóstico por imagen , Paraganglioma/cirugía , Hipófisis/diagnóstico por imagen , Hipófisis/cirugía , Neoplasias Hipofisarias/diagnóstico por imagen , Neoplasias Hipofisarias/cirugía , Silla Turca/diagnóstico por imagen , Silla Turca/cirugía , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
13.
J Neural Transm (Vienna) ; 113(6): 757-67, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16755380

RESUMEN

In this study a comparative analysis of iron molecules during aging was performed in locus coeruleus (LC) and substantia nigra (SN), known targets of Parkinson's Disease (PD) and related disorders. LC and SN neurons, especially the SN pars compacta, degenerate in PD and other forms of parkinsonism. Iron and its major molecular forms, such as ferritin and neuromelanin (NM), were measured in LC and SN of normal subjects at various ages. Iron levels were lower, H-ferritin/iron ratio was higher and the iron content in NM was lower in LC than in SN. Iron deposits were abundant in SN tissue, very scarse in LC tissue and completely absent in pigmented neurons of both SN and LC. In both regions H- and L-ferritins were present only in glia. This suggests that in LC neurons iron mobilization and toxicity is lower than that in SN and is efficiently buffered by NM. Ferritins accomplish the same buffering function in glial cells.


Asunto(s)
Envejecimiento , Hierro/análisis , Locus Coeruleus/química , Melaninas/análisis , Neuronas/química , Sustancia Negra/química , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Ferritinas/análisis , Humanos , Quelantes del Hierro/química , Locus Coeruleus/citología , Masculino , Persona de Mediana Edad , Neuroglía/química , Neuroglía/citología , Neuronas/citología , Sustancia Negra/citología
14.
Artículo en Inglés | MEDLINE | ID: mdl-16732881

RESUMEN

Vaccination with bacterins is an important tool for the control of Mycoplasma hyopneumoniae infection of pigs. Because such vaccination often involves piglets that have suckled M. hyopneumoniae antibody-positive dams it is important to understand the effect of pre-existing (passively acquired) antibody on vaccine-induced immunity. To investigate this issue experimentally, 20 sows that were seronegative for M. hyopneumoniae were selected from a M. hyopneumoniae-infected herd and then randomly allocated to one of four treatment groups (five sows/group): Group A, vaccinated sows/vaccinated piglets; Group B, vaccinated sows/non-vaccinated piglets; Group C, non-vaccinated sows/vaccinated piglets; Group D, non-vaccinated sows/non-vaccinated piglets. Sows (Groups A and B) were vaccinated 14 days before farrowing and seroconverted within the next 14 days. Conversely, none of the non-vaccinated sows was seropositive at farrowing. Piglets (Groups A and C) were vaccinated when they were 7 days of age. Regardless of treatments none of the piglets had any evidence of an active immune response until many of those of Groups A and C and a few of those of Groups B and D seroconverted after it had been shown that at least some pigs of all groups had been naturally infected with a field strain of M. hyopneumoniae. This pattern of immune responsiveness (i.e. the collective results of Groups A, B, C and D) suggested that vaccination of pigs had primed their immune system for subsequent exposure to M. hyopneumoniae, and that passively acquired antibody had little or no effect on either a vaccine-induced priming or a subsequent anamnestic response. According to the statistical analysis sow serological status did not interfere with the antibody response in early vaccinated piglets. In conclusion, the results pointed out that early vaccination of piglets may assist M. hyopneumoniae control independently from the serological status of sows.


Asunto(s)
Animales Lactantes/inmunología , Anticuerpos Antibacterianos/sangre , Mycoplasma hyopneumoniae/inmunología , Neumonía Porcina por Mycoplasma/prevención & control , Neumonía Porcina por Mycoplasma/transmisión , Animales , Animales Lactantes/microbiología , Calostro/inmunología , Calostro/microbiología , Ensayo de Inmunoadsorción Enzimática/métodos , Ensayo de Inmunoadsorción Enzimática/veterinaria , Femenino , Mycoplasma hyopneumoniae/aislamiento & purificación , Neumonía Porcina por Mycoplasma/inmunología , Reacción en Cadena de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa/veterinaria , Embarazo , Distribución Aleatoria , Estudios Seroepidemiológicos , Porcinos
15.
Biotechnol Prog ; 20(3): 825-9, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15176888

RESUMEN

The porcine pancreatic lipase (PPL) extracts contain a mixture of several lipases. Their fractioning was performed by sequential adsorption via interfacial activation on supports with different hydrophobicity. A protein of 25 KDa was preferentially adsorbed on octyl-Sepharose, another protein of 33 kDa was mainly adsorbed on octadecyl-Sepabeads support, and the PPL was mainly adsorbed on the support bearing phenyl groups. The different immobilized preparations showed different properties and different response due to change in the experimental conditions. Thus, in the hydrolysis of (+/-)-2-hydroxy-4-phenylbutyric acid ethyl ester [(+/-)-1] to produce the corresponding acid [2], the octyl-25KDa preparation showed the best enantioselectivity (E) value (E = 7) at pH 5 and 25 degrees C, whereas the phenyl-PPL was the most enantioselective (E = 10) at pH 5, 4 degrees C, and 10% dioxane. Using different preparations at different pHs it was possible to resolve (+/-)-2-O-butyryl-2-phenylacetic acid [(+/-)-3] with a high E value (E > 100); for example, with octadecyl-33 KDa enzyme at pH 8.


Asunto(s)
Extractos Celulares/química , Extractos Celulares/aislamiento & purificación , Lipasa/química , Lipasa/aislamiento & purificación , Páncreas/enzimología , Animales , Extractos Celulares/clasificación , Cromatografía en Agarosa/métodos , Activación Enzimática , Estabilidad de Enzimas , Enzimas Inmovilizadas/química , Precipitación Fraccionada , Concentración de Iones de Hidrógeno , Isoenzimas , Cinética , Lipasa/clasificación , Estereoisomerismo , Especificidad por Sustrato , Porcinos , Temperatura
16.
J Neurol Neurosurg Psychiatry ; 75(6): 889-92, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15146007

RESUMEN

OBJECTIVES: The aim of the study was to correlate the Ki-67 and cyclin A labelling index (LI) with clinical characteristics and risk of recurrence of craniopharyngiomas. METHODS: 47 consecutive patients were studied, 21 female and 26 male, aged 34.3 (2.8) years. Immunohistochemical analysis was performed on paraffin wax embedded material using monoclonal antibodies directed against the proliferation associated nuclear antigen Ki-67 and cyclin A. RESULTS: The median Ki-67 LI was 8.6% (interquartile range, 4.4%-14.0%). Ki-67 LI was significantly higher in tumours with a heavy inflammatory reaction and diabetes insipidus at presentation, whereas other clinical and histological features were not associated with the proliferation index. There was a strong linear correlation between Ki-67 LI and cyclin A LI (r = 0.77; p<0.0001); therefore, cyclin A LI showed the same clinical and histological relations described for Ki-67 LI. Recurrence of craniopharyngioma occurred in 13 of 46 patients (28.3%). The median Ki-67 LI in the 13 recurrent craniopharyngiomas (9.0%) was not significantly different from that of non-recurring tumours (7.9%). Cyclin A LI was also not associated with the risk of relapse. CONCLUSIONS: This study confirms the great variability of proliferative activity in craniopharyngiomas. Ki-67 and cyclin A LIs were associated with the presence of a heavy inflammatory reaction and diabetes insipidus, but did not correlate with the long term risk of tumour regrowth.


Asunto(s)
Neoplasias Encefálicas/cirugía , Ciclo Celular/fisiología , Craneofaringioma/cirugía , Recurrencia Local de Neoplasia/diagnóstico , Adolescente , Adulto , Anciano , Anticuerpos Monoclonales , Biomarcadores de Tumor/metabolismo , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/metabolismo , Ciclo Celular/inmunología , Niño , Craneofaringioma/diagnóstico , Craneofaringioma/metabolismo , Ciclina A/metabolismo , Femenino , Humanos , Inmunohistoquímica , Antígeno Ki-67/metabolismo , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/metabolismo , Factores de Riesgo
17.
Ann Oncol ; 13(11): 1827-32, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12419758

RESUMEN

BACKGROUND: Primary central nervous system lymphomas (PCNSLs) are rare tumors, mostly represented by diffuse large B cells. PCNSLs with a T phenotype are less frequently reported; even rarer are anaplastic large cell lymphomas (ALCLs). PCNSL ALCLs are commonly represented, like their systemic counterpart, by a variably prevalent amount of large pleomorphic tumor cells ('hallmark cells'), and this feature enhances their recognition. Patient and methods We report the first case of primary brain CD30+ ALK-1+ ALCL with a T-cell phenotype, showing the combination of both the 'lymphohistiocytic' and the 'small cell' variants of the disease. A few elements consistent with 'hallmark cells' were recognizable. However, these cells were never prominent, increasing diagnostic difficulties. Immunohistochemistry results were critical for the correct interpretation. Our findings also differ from the majority of PCNSL ALCLs for the absence of tumor necrosis and the lack of prominent mitotic activity. The neuroimaging picture was not specific. A comparison with literature data concerning the clinical/instrumental features shows a very frequent meningeal involvement in PCNSL ALCLs, in contrast to the majority of PCNSLs. CONCLUSION: The occurrence of such a rare form of ALCL may widen the spectrum of differential diagnoses in PCNSL and their recognition may allow a rapid diagnosis, thus encouraging adequate treatment, which should take into account the high rate of meningeal involvement observed in these cases.


Asunto(s)
Neoplasias Encefálicas/patología , Antígeno Ki-1/análisis , Linfoma Anaplásico de Células Grandes/patología , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Biopsia con Aguja , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/inmunología , Estudios de Seguimiento , Humanos , Inmunocompetencia , Inmunohistoquímica , Linfoma Anaplásico de Células Grandes/tratamiento farmacológico , Linfoma Anaplásico de Células Grandes/inmunología , Imagen por Resonancia Magnética , Masculino , Estadificación de Neoplasias , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
18.
Biomacromolecules ; 2(1): 95-104, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11749160

RESUMEN

The importance of the stabilization of the quaternary structure of multimeric enzymes has been illustrated using a model reaction with great industrial relevance: the enzymatic synthesis of ampicillin from 6-amino penicillanic acid (6APA) and phenylglycine methyl ester (PGM) catalyzed by the tetrameric enzyme alpha-amino acid ester hydrolase from Acetobacter turbidans. The stabilization of the multimeric structure of the enzyme was achieved by multi-subunit immobilization of the enzyme followed by its further solid-phase chemical intersubunit cross-linking with polyfunctional macromolecules (dextran-aldehyde). This stabilized derivative has permitted the study of the reaction under conditions where nonstabilized enzyme molecules tended to dissociate (e.g., absence of phosphate ions). Synthetic yields improved from around 65%, under conditions where the nonstabilized derivative was stable, to around 85% in conditions where only the stabilized derivative could be utilized (40% methanol and absence of phosphate ions). When using high concentrations of PGM, a significant worsening of the reaction performance was detected with a significant decrease in the yields (below 55%, using 50 mM 6APA and PGM). This problem has been sorted out by using a fed-batch reaction system. By addition of PGM continuously to the reaction mixture (to maintain the concentration between 0.5 and 3 mM), 95% of 6-APA could be transformed to antibiotic (47.5 mM) by only using a 20% excess of acylating ester.


Asunto(s)
Ampicilina/metabolismo , Reactores Biológicos , Glicina/análogos & derivados , Ácido Penicilánico/análogos & derivados , Penicilina Amidasa/química , Penicilina Amidasa/metabolismo , Acetobacter/enzimología , Catálisis , Estabilidad de Enzimas , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Escherichia coli/enzimología , Glicina/metabolismo , Concentración de Iones de Hidrógeno , Cinética , Metanol , Estructura Molecular , Ácido Penicilánico/metabolismo , Fosfatos , Estructura Cuaternaria de Proteína , Temperatura
19.
J Clin Endocrinol Metab ; 86(11): 5194-200, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11701676

RESUMEN

To investigate the effects of octreotide administration on the growth rate of GH-secreting pituitary adenomas, we measured both the Ki-67 labeling index (LI) and the apoptotic index in tumor specimens from octreotide-treated or matched untreated acromegalic patients. Thirty-nine patients who received octreotide until the day of or the day before surgery and 39 untreated patients matched for sex, age, tumor size, extension, and invasiveness were studied. Immunocytochemical analysis was performed on paraffin-embedded material using a monoclonal antibody (MIB-1) directed against a proliferation-associated nuclear antigen, Ki-67, to measure the growth fraction. Apoptosis was assessed by the terminal deoxynucleotidyl transferase-mediated deoxy-UTP nick endlabeling method, using a monoclonal antibody recognizing areas of DNA fragmentation. The Ki-67 LI and apoptosis were counted on separate slides in at least 1000 evaluable cells. Octreotide-treated patients showed a lower Ki-67 LI (1.8 +/- 0.3%) than untreated controls (3.8 +/- 0.7%; P < 0.02). Overall, the mean Ki-67 LI of treated patients was 53% lower than that in untreated patients. The antiproliferative effect of octreotide occurred independently of tumor extension and invasiveness. Octreotide-treated and untreated patients showed similar apoptotic indexes (0.6 +/- 0.2% and 0.8 +/- 0.3%, respectively). There was a positive correlation between the Ki-67 LI and the apoptotic index (r = 0.29; P < 0.03). Our study demonstrates that acromegalic patients receiving chronic octreotide treatment have a lower value of the proliferation marker Ki-67, but no significant difference in the apoptotic index compared with matched untreated patients. The antiproliferative effect of octreotide on GH-secreting adenomas should imply a lower risk of tumor growth during long-term chronic treatment with the drug.


Asunto(s)
Adenoma/metabolismo , Apoptosis/efectos de los fármacos , Hormonas/uso terapéutico , Hormona de Crecimiento Humana/biosíntesis , Octreótido/uso terapéutico , Neoplasias Hipofisarias/metabolismo , Acromegalia/patología , Adenoma/patología , Adulto , Anticuerpos Monoclonales/farmacología , División Celular , Femenino , Humanos , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Antígeno Ki-67 , Masculino , Neoplasias Hipofisarias/patología , Adhesión del Tejido
20.
Neuroradiology ; 43(8): 599-607, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11548164

RESUMEN

MRI findings in primary angiitis of the central nervous system (PACNS) are highly variable, ranging from normal to diffusely abnormal. We describe brain and spinal cord abnormalities in patients with PACNS and changes over time, to provide criteria which could be useful for differential diagnosis. We reviewed six patients, with a final diagnosis of PACNS, who underwent serial contrast-enhanced brain and spinal MRI. Follow-up ranged from 12 to 60 months. Brain MRI showed multiple small abnormalities in all patients, giving high signal on T2-weighted images, focal or diffuse, mainly in deep and subcortical white matter; four patients had both supra- and infratentorial lesions. On the initial MRI, in five patients, almost 90% of the abnormal foci showed contrast enhancement. Virchow-Robin perivascular spaces were enlarged and simultaneously enhancing in four patients. Three patients also had spinal cord abnormalities, in the cervical and thoracic segments in two, and exclusively cervical segment in one. Two patients had brain biopsy-proven PACNS; in the remainder, the diagnosis of PACNS was presumptive, considering similarities in clinical and MRI features and MRI follow-up. On MRI, after steroid and immunosuppressive therapy, a significant decrease in the number and size of the abnormalities, enhancing and nonenhancing and of enhancing perivascular spaces was observed. Simultaneous enhancement of brain and spinal cord lesions and of perivascular spaces, at the onset of the disease, which resolves during follow-up, can therefore suggest PACNS.


Asunto(s)
Vasculitis del Sistema Nervioso Central/diagnóstico , Adolescente , Adulto , Biopsia , Encéfalo/diagnóstico por imagen , Angiografía Cerebral , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Angiografía por Resonancia Magnética , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Médula Espinal/diagnóstico por imagen
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