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2.
Neuropathol Appl Neurobiol ; 30(2): 118-25, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15043709

RESUMEN

Much of the morbidity of intracranial meningiomas is related to the degree of tumour vascularity and the extent of peritumoural vasogenic oedema. Several studies have shown that vascular endothelial growth factor (VEGF) is up-regulated in meningiomas, although its relationship with tumour vasculature is still unclear. In order to better understand the angiogenic assessment of intracranial meningiomas, we analysed its vascular pattern, both as number and as morphologic configuration of microvessels. Moreover, we investigated the mRNA-VEGF expression, relating this expression to vascular pattern. A total of 40 intracranial meningiomas, classified as benign (31 cases), atypical (7 cases), and anaplastic (2 cases) were analysed. RT-PCR analyses of mRNA-VEGF and competitive-PCR were performed. VEGF expression and microvessel density (MVD) were also immunohistochemically investigated. Grade II-III meningiomas showed numerous small microvessels (mean: 34), while the majority of Grade I showed few larger vessels (mean: 13.09) (P = 0.000003). A microvessel pattern overlapping into atypical subtype was found in eignt of the 31 (25.8%) Grade I meningiomas. A significant association was found between grading and vascular pattern (P = 0.0002), as well as between the MVD and the immunohistochemical expression of VEGF (P = 0.0005). The expression of mRNA agreed with the immunohistochemical expression of the protein (P < 0.0001). A total of 39 cases expressed the 121 VEGF isoform and, among these, 28 cases also expressed the 165 isoform. Only 9 cases expressed both isoforms 165 and 189. Grade II and III meningiomas showed a preponderant expression of soluble isoforms (121 and 165). These results prompt us to speculate that the microvessel pattern could underlie a higher metabolic demand, probably due to a rapid growth with a consequent worse clinical behaviour of the tumour. In this sense, the vascular pattern may be used as a prognostic factor, in order to mostly focus attention on those Grade I meningiomas which have a higher likelihood of either recurrence or development of perilesional oedema. The pattern of vasculature itself seems to be dependent on the types of VEGF isoforms: the Grade II-III meningiomas (that presented numerous microvessels) expressed the soluble isoforms 121 and 165, while the isoform 189 was more frequently detected in Grade I meningiomas.


Asunto(s)
Neoplasias Meníngeas/patología , Meningioma/patología , Neovascularización Patológica/patología , Adulto , Anciano , Anciano de 80 o más Años , Edema Encefálico/patología , Femenino , Humanos , Inmunohistoquímica , Antígeno Ki-67/metabolismo , Masculino , Neoplasias Meníngeas/metabolismo , Meningioma/metabolismo , Persona de Mediana Edad , Neovascularización Patológica/metabolismo , Pronóstico , Isoformas de Proteínas/biosíntesis , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor A de Crecimiento Endotelial Vascular/biosíntesis
3.
Int J Mol Med ; 12(6): 943-7, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14612971

RESUMEN

Telomere length maintenance is essential for tumorigenesis; most human tumors stabilize their chromosome ends via the activity of a specialized reverse transcriptase, telomerase, that uses the template region of the RNA moiety complementary to the TTAGGG repeat to synthesize one strand of telomeric DNA. Meningiomas are estimated to constitute between 13% and 26% of primary intracranial tumors. The aim of this study was to evaluate telomerase activity and its messenger expression in meningiomas in relation to their different histologic pattern and grade of cytonuclear atypies, which are associated with relapse, and consequently represent the most important parameter for the evaluation of the clinical behavior of this tumor. Telomerase activity was examined by the telomeric repeat amplification protocol (TRAP) assay in 32 meningiomas (26 typical and 6 atypical/anaplastic). Telomerase messenger expression (hTERT mRNA) was evaluated by reverse transcription-PCR analysis in the same group of tumors. Telomerase activity ranged from undetectable to low levels in 19/26 (73%) of typical meningiomas, while all the atypical/anaplastic meningiomas showed medium-high levels of activity (>3 TPG units, median value), (chi(2) test; p=0.001). The levels of telomerase in terms of its messenger level expression overlapped the activity; a significant association between telomerase activity and hTERT mRNA expression was also found (chi(2) test; p=0.01). Moreover, 2 atypical/anaplastic meningiomas of our series relapsed; in these samples we found high levels of telomerase, both in terms of activity and mRNA expression. Telomerase activity and its hTERT mRNA expression tended to increase as the histologic grading of intracranial tumors increased, suggesting a role of telomerase reactivation in the progression of these tumors. Moreover, our results indicate RT-PCR assay as a rapid tool to identify and quantify telomerase RNA in intracranial meningiomas as in other human tumor models.


Asunto(s)
Neoplasias Encefálicas/enzimología , Meningioma/enzimología , Telomerasa/metabolismo , Proteínas de Unión al ADN , Humanos , ARN Mensajero/metabolismo , Telomerasa/genética
4.
Int J Mol Med ; 11(5): 607-11, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12684697

RESUMEN

Telomerase, a ribonucleoprotein, is capable of adding telomeric sequences (TTAGGG hexameric repeats) to the ends of chromosomes and, thereby, halting the erosion of chromosome at each cell division. Whereas most normal somatic cells contain minimal or no detectable telomerase activity, most immortal and tumour cells exhibit significant levels of telomerase activity and show no net loss of telomere length during proliferation. The evaluation of telomerase has been proposed for diagnostic and therapeutic purposes in human cancer. Skin cancer is the most common cancer in humans; the precise molecular events in skin carcinogenesis are numerous and complicated and not yet completely clarified. In this study, we evaluated telomerase in 35 basal cell carcinomas and in 14 squamous cell carcinomas in order to determine if activation of the telomerase enzyme was a pivotal step in the development of skin cancer and whether telomerase activity levels were different between the two histotypes. A higher enzymatic level was shown to be associated with squamous cell carcinomas, while low levels were mainly detected in the basal cell histotype (chi2 test; p=0.02). Telomerase complex activity is dependent on its catalytic subunit, telomerase reverse transcriptase hTERT. By reverse transcription-PCR, using primers within the reverse transcriptase domain of hTERT, we observed a significant correlation between hTERT expression and telomerase activity in our skin tumour samples (p=0.0003). We detected the presence of multiple, alternately spliced transcripts, corresponding to full-length messages as well as spliced messages with critical reverse transcriptase motifs deleted. A higher telomerase messenger level was shown to be associated with squamous cell carcinomas (chi2 test; p<0.0001), as for telomerase activity. Our results provide arguments supporting the role of telomerase in skin cancer and suggest RT-PCR of telomerase RNA as a tool easier and faster than TRAP assay to identify more aggressive malignancies among non-melanoma skin specimens.


Asunto(s)
Carcinoma Basocelular/enzimología , Carcinoma de Células Escamosas/enzimología , Neoplasias Cutáneas/enzimología , Telomerasa/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Proteínas de Unión al ADN , Femenino , Humanos , Masculino , Persona de Mediana Edad , Telomerasa/genética
5.
Int J Mol Med ; 10(5): 589-92, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12373297

RESUMEN

Telomerase activity, a cardinal requirement for immortalization, is a crucial step in the development of cancer and has been studied in many kinds of malignant tumours for clinical diagnostic and/or prognostic utilities. Using a PCR-based TRAP assay, we investigated telomerase activity in 8 adenomatous polyps, 9 dysplastic polyps, and in 36 paired cancer-normal mucosa specimens, one liver and one spleen metastasis from patients resected for sporadic colorectal cancer. Telomerase was absent or very low in normal mucosa and in adenomatous polyps. Dysplastic polyps and adenocarcinoma samples showed telomerase activity, with higher levels in cancer tissues compared to dysplastic lesions. A high telomerase activity was shown to be associated with late-staged cancers and metastasis, providing arguments supporting the role of telomerase not only in the development but also in the progression of colorectal carcinoma. Moreover, telomerase evaluation may help to confirm the malignant transformation in polypoid colorectal lesions with different levels of dysplastic alterations.


Asunto(s)
Neoplasias del Colon/enzimología , Neoplasias del Colon/etiología , Telomerasa/metabolismo , Adenocarcinoma/enzimología , Adenocarcinoma/etiología , Adenocarcinoma/genética , Adenocarcinoma/secundario , Pólipos Adenomatosos/enzimología , Pólipos Adenomatosos/etiología , Pólipos Adenomatosos/genética , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias del Colon/genética , Pólipos del Colon/enzimología , Pólipos del Colon/etiología , Pólipos del Colon/genética , Neoplasias Colorrectales/enzimología , Neoplasias Colorrectales/etiología , Neoplasias Colorrectales/genética , Femenino , Humanos , Neoplasias Hepáticas/enzimología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/secundario , Masculino , Persona de Mediana Edad , Neoplasias del Bazo/enzimología , Neoplasias del Bazo/genética , Neoplasias del Bazo/secundario , Telomerasa/genética
6.
Int J Oncol ; 21(3): 493-7, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12168091

RESUMEN

Telomerase activation, a cardinal requirement for immortalization, is a crucial step in the development of malignancy and requires the induction of the catalytic component, human telomerase reverse transcriptase (hTERT), encoded by the hTERT gene. By reverse transcription-PCR, using primers within the reverse transcriptase domain of hTERT, we investigated telomerase messenger in 8 adenomatous and 9 dysplastic polyps, and in 32 paired cancer-normal mucosa specimens, one liver and one spleen metastasis from patients resected for sporadic colorectal cancer. Telomerase messenger was absent or very low in normal mucosa and in adenomatous polyps. Dysplastic polyps and adenocarcinoma samples showed hTERT mRNA, with higher levels in cancer tissues compared to dysplastic lesions. A high telomerase messenger level was shown to be associated with late-staged cancers and with metastasis; thus, detection of telomerase messenger may be useful in the early diagnosis of colon cancer, and telomerase may be a new target for therapeutic intervention.


Asunto(s)
Neoplasias del Colon/enzimología , ARN Mensajero/biosíntesis , Telomerasa/genética , Adenoma/enzimología , Adenoma/genética , Adenoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Empalme Alternativo , Neoplasias del Colon/genética , Neoplasias del Colon/patología , Pólipos del Colon/enzimología , Pólipos del Colon/genética , Pólipos del Colon/patología , Proteínas de Unión al ADN , Femenino , Humanos , Mucosa Intestinal/enzimología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , ARN Mensajero/genética , Telomerasa/biosíntesis
7.
Oncol Rep ; 9(3): 617-20, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-11956638

RESUMEN

Angiogenesis is an essential requirement for the development, progression and metastasis of malignant tumors. Vascular endothelial growth factor (VEGF) plays an essential role in the development of angiogenesis of numerous solid malignancies, including colon cancer. The tumor suppressor gene p53 is a potent transcriptional regulator of genes which are involved in many cellular activities, including cell-cycle arrest, apoptosis and angiogenesis. In order to better understand the relation among p53 status, VEGF expression and microvessels count (MVC) in colon cancer, we evaluated immunoreactivity for CD34 endothelium-associated antigen, VEGF and p53 proteins in 43 cases of colon adenocarcinoma. Our results demonstrated an association between VEGF expression, p53 status and angiogenesis, suggesting that mutant p53 plays a central role in promoting angiogenesis in colon cancer progression.


Asunto(s)
Neoplasias del Colon/irrigación sanguínea , Factores de Crecimiento Endotelial/biosíntesis , Linfocinas/biosíntesis , Neovascularización Patológica , Proteína p53 Supresora de Tumor/biosíntesis , Anciano , Antígenos CD34/biosíntesis , Neoplasias del Colon/metabolismo , Progresión de la Enfermedad , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Mutación , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
8.
Br J Cancer ; 86(4): 558-63, 2002 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-11870537

RESUMEN

It has been widely demonstrated that neo-angiogenesis and its mediators (i.e. vascular endothelial growth factor), represent useful indicators of poor prognosis in non small cell lung carcinoma. In order to verify whether neovascularization and vascular endothelial growth factor may be considered useful markers of clinical outcome also in the small cell lung cancer subgroup, we retrospectively investigated a series of 75 patients with small cell lung carcinoma treated by surgery between 1980 and 1990. Immunohistochemically-detected microvessels and vascular endothelial growth factor expressing cells were significantly associated with poor prognosis, as well as with nodal status and pathological stage. In fact, patients whose tumours had vascular count and vascular endothelial growth factor expression higher than median value of the entire series (59 vessels per 0.74 mm(2) and 50% of positive cells, respectively), showed a shorter overall and disease-free survival (P=0.001, P=0.001; P=0.008, P=0.03). Moreover, the presence of hilar and/or mediastinal nodal metastasis and advanced stage significantly affected overall and disease-free interval (P=0.00009, P=0.00001; P=0.0001, P=0.00001). At multivariate analysis, only vascular endothelial growth factor expression retained its influence on overall survival (P=0.001), suggesting that angiogenic phenomenon may have an important role in the clinical behaviour of this lung cancer subgroup.


Asunto(s)
Carcinoma de Células Pequeñas/metabolismo , Factores de Crecimiento Endotelial/metabolismo , Neoplasias Pulmonares/metabolismo , Linfocinas/metabolismo , Neovascularización Patológica/patología , Adulto , Anciano , Carcinoma de Células Pequeñas/irrigación sanguínea , Carcinoma de Células Pequeñas/cirugía , Recuento de Células , Femenino , Humanos , Técnicas para Inmunoenzimas , Neoplasias Pulmonares/irrigación sanguínea , Neoplasias Pulmonares/cirugía , Masculino , Microcirculación/patología , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia , Proteína p53 Supresora de Tumor/metabolismo , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
9.
J Neurooncol ; 60(2): 159-64, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12635663

RESUMEN

BACKGROUND: Approximately 60% of meningiomas are associated with perilesional brain oedema. Several aspects have been evaluated in order to understand the pathophysiological mechanisms of oedema (age, sex of the patient, size and location of the tumour, histotype, grading), although at present they have yet to be completely clarified. We focused on pial blood supply, microvascular density (MVD) and angiogenic growth factors (i.e. vascular endothelial growth factor--VEGF) in order to evaluate their putative role in the development of brain oedema. METHODS: We retrospectively studied 55 patients with intracranial meningiomas. Computerized tomography (CT) and angiographic studies were obtained in all cases. The angiograms provided an accurate differentiation between pial and dural blood supply, concomitantly with its semi-quantitative evaluation. The location and the volume of oedema, in relation to the meningioma surface, was evaluated using CT scans, as an oedema index (E/I). We also determined the expression of VEGF and MVD using standard immunohistochemical methods. RESULTS: Thirty-two out of 55 meningiomas presented peritumoural oedema, with an angiographic blush ranging from 2 to 4; VEGF protein was expressed in 27 out of 32 cases, independent of grade or histotype of tumours. In all patients, MVD ranged from 4 to 33.3 vessels (median value: 10.6). A significant relationship was found between the expression of VEGF and MVD (p = 0.0003) and between VEGF and E/I (p = 0.0023). Moreover, the E/I ratio was related to the blush (p = 0.0005). A significant association was also present between VEGF expression and pial blush (p = 0.0001). CONCLUSION: Our data confirm the central role of VEGF and pial blood supply in the pathogenesis of peritumoural oedema and support the hypothesis that the development of oedema in meningioma is vasogenic in type.


Asunto(s)
Edema Encefálico/etiología , Factores de Crecimiento Endotelial/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Linfocinas/metabolismo , Neoplasias Meníngeas/complicaciones , Meningioma/complicaciones , Piamadre/irrigación sanguínea , Adulto , Anciano , Edema Encefálico/diagnóstico por imagen , Edema Encefálico/metabolismo , Angiografía Cerebral , Femenino , Humanos , Masculino , Neoplasias Meníngeas/diagnóstico por imagen , Neoplasias Meníngeas/metabolismo , Meningioma/diagnóstico por imagen , Meningioma/metabolismo , Persona de Mediana Edad , Neovascularización Patológica/diagnóstico por imagen , Neovascularización Patológica/etiología , Neovascularización Patológica/metabolismo , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
10.
Tumori ; 87(4): 252-5, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11693803

RESUMEN

AIMS AND BACKGROUND: The B72.3, MM1.80 and 4.63 monoclonal antibodies directed against tumor-associated antigens react in human breast also with metaplastic, preneoplastic and metastatic cells, whereas they do not react with normal adult mammary tissue. The aim of our study was to point out the expression of these antigens during mammary gland development, since tumor-associated antigens are known to represent antigens of differentiation. STUDY DESIGN: Fifty female fetal breasts between 20 and 40 weeks of gestational age were studied. RESULTS: Mammary tissue was identified only in 15 cases. B72.3, MM1.80 and 4.36 monoclonal antibodies reacted with epithelial antigens and maintained the same location and intensity in the various gestational ages. Immunoreactivity was weak, cytoplasmic and widespread for the 4.36 monoclonal antibody, intense and cytoplasmatic in a large number of cells for the B72.3 monoclonal antibody, and intense and luminal for the MM1.80 monoclonal antibody. CONCLUSIONS: Such data further support the hypothesis that the normal process of development and differentiation can occur during tumor progression processes. Identification of these new oncofetal markers could offer a new perspective able to recognize the different phases of neoplastic progression and could be useful for prevention.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Antígenos de Neoplasias/inmunología , Mama/embriología , Mama/inmunología , Femenino , Humanos , Inmunohistoquímica
11.
J Am Acad Dermatol ; 45(4): 606-8, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11568755

RESUMEN

Lichen myxedematosus is a rare disease that is characterized by the formation of lichenoid papules and plaques. Histologic examination shows deposition of mucinous material in the dermis. We report the case of a patient with cutaneous and systemic involvement and examine the clinical and postmortem data.


Asunto(s)
Mucinosis/patología , Enfermedades Cutáneas Papuloescamosas/patología , Anciano , Ascitis/etiología , Autopsia , Sistema Digestivo/patología , Femenino , Humanos
12.
Tumori ; 87(3): 179-86, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11504374

RESUMEN

AIMS AND BACKGROUND: Thickness and level of invasion are the main morphological elements for an approximate but not sufficiently sensitive prognostic evaluation of cutaneous melanomas. By using immunohistochemical methods it is possible to detect biological markers related to prognosis. We have studied p53, PCNA, Bcl-2 and P-gp expression in 49 primary cutaneous melanomas. MATERIALS: We used the immunophosphatase APAAP immunohistochemical method. The percentage of labeled cells (according to four classes of positivity: <5%; 5-25%; 25-50%; >50%) and the localization of immunoreactivity were expressed for each marker. Statistical analysis was performed to determine the correlations between markers and level or thickness of melanomas. RESULTS: We found a good correlation between p53 expression and melanoma thickness (P <0.005), PCNA and P-gp expression. No relationship was observed between Bcl-2 expression and the different variables considered or other markers. CONCLUSIONS: Our data seem to indicate an unfavorable prognostic role of higher nuclear p53 expression. However, we believe that our results need to be integrated with patients' clinical follow-up and with the study of the expression of these markers in benign melanocytic lesions to gain more accurate information about their prognostic significance.


Asunto(s)
Biomarcadores de Tumor/análisis , Resistencia a Antineoplásicos , Melanoma/patología , Antígeno Nuclear de Célula en Proliferación/análisis , Proteínas Proto-Oncogénicas c-bcl-2/análisis , Neoplasias Cutáneas/patología , Proteína p53 Supresora de Tumor/análisis , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/análisis , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Masculino , Melanoma/química , Melanoma/tratamiento farmacológico , Melanoma/mortalidad , Persona de Mediana Edad , Invasividad Neoplásica , Valor Predictivo de las Pruebas , Pronóstico , Neoplasias Cutáneas/química , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/mortalidad , Estadísticas no Paramétricas , Análisis de Supervivencia
14.
Ann Ital Chir ; 72(3): 323-7, 2001.
Artículo en Italiano | MEDLINE | ID: mdl-11765350

RESUMEN

OBJECTIVE: Carcinoma of the rectal colon begins as a small neoplastic polyp which gradually increases in size and, after passing through various degrees of dysplasia, develops into an overtly malignant carcinoma. Clinical experience suggests that patients may be divided into subgroups based on the aggressivity of the tumour. The genetic mutations associated with colorectal cancer have been studied and it is known that the genes primarily responsible for biological changes in the tumour cell, in the early stages, are APC, hMSH2, k-ras2 and, in particular, p53. Indeed, the mutation at the level of gene p53 has been recognized as the most common mutation in tumour cells. The aim of this study was investigate the role of p53 and CD34 in colorectal cancer. METHODS: We studied p53 positivity using immunohistological methods and compared our results with the site, stage (using the TNM system) and histological grade of the tumour. We evaluated CD34 positivity using the same methods in order to detect and quantity the presence of angiogenesis in colorectal cancer. RESULT: P53 was found to be markedly raised in the T3 stage of colorectal cancer, while its expression was decreased in stage T2 and stage T1 carcinomas and it was not detectable in adenomas. These results suggest a close correlation between the tumour stage and the expression of p53. An analogous correlation was found between CD34 expression and angiogenesis. CONCLUSION: The overexpression of p53 in epithelial cells and raised angiogenesis (as reflected in CD34 levels) in stromal cells could represent useful prognostic factors in the management of colorectal cancer.


Asunto(s)
Neoplasias Colorrectales/genética , Anciano , Neoplasias Colorrectales/patología , Humanos , Persona de Mediana Edad
15.
Am J Otol ; 21(6): 799-803, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11078066

RESUMEN

OBJECTIVE: To evaluate the inner anatomy of the auditory apparatus by means of virtual endoscopy of spiral computed tomography (CT) data sets. BACKGROUND: Virtual endoscopy permits simulation of the fiberoptic endoscopy perspective by processing CT or magnetic resonance images. METHODS: Seven formalin-fixed specimens of human mastoid were scanned with spiral CT with the following protocol: beam collimation 1 mm, pitch ratio 1, reconstruction spacing 0.2 to 0.5 mm, field of view 90 mm. For the generation of endoscopic views of the auditory spaces, the axial images were processed with Navigator software 2.0 running on UltraSparc I workstation. RESULTS: Virtual endoscopy allowed the demonstration of the external auditory canal, the head and handle of the malleus, the stapes and incudostapedial articulation, the corpus, the long process of the incus with its lenticular process and the short limb, the malleoincudal articulation, the rounded promontory, the round and oval windows, and Prussak's space. From inside the basal turn of the cochlea, virtual endoscopy showed the orifices of the fenestrae cochlea and vestibuli, the origin of the lateral and the anterior semicircular canals, and the basal turn of cochlea. The optimal perspectives that allowed demonstration of the anatomical details of the middle and inner ear are described. CONCLUSION: Virtual endoscopy allows the generation of inner views of the auditory spaces. This new method of image processing can be proposed as an integrative tool of spiral CT imaging.


Asunto(s)
Oído Interno/diagnóstico por imagen , Oído Medio/diagnóstico por imagen , Endoscopía/métodos , Procedimientos Quirúrgicos Otológicos/métodos , Tomografía Computarizada por Rayos X , Interfaz Usuario-Computador , Técnicas de Cultivo , Humanos , Apófisis Mastoides/diagnóstico por imagen , Terapia Asistida por Computador
16.
Addict Behav ; 25(5): 641-52, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11023008

RESUMEN

The present study examined whether individual differences in personality could differentiate two types of cocaine users. We hypothesized that self-medicators (SM) use cocaine as a way to alleviate their dysphoric moods, whereas sensation seekers (SS), in contrast, use cocaine primarily to engender positive mood states. Eighteen male cocaine users were classified based on two dimensions of the Tridimensional Personality Questionnaire. SM were defined by having high harm avoidance (>17) and low novelty-seeking scores (<18), and SS by high novelty-seeking (>18) and low harm-avoidance scores (<17). It was predicted that SM would report higher depression and anxiety than would SS, and would also exhibit a brain activity pattern similar to that found in clinical depression. The results showed that SM reported higher anxiety than SS, F(1, 8) = 27.5, p < .001, but did not differ in depression. SM exhibited decreased blood flow within the left frontal lobes, F(1, 10) = 6.78, p < .05, similar to what has been observed in major depressive disorder. These findings suggest the importance of attending to individual differences in the motivation for cocaine use so that treatment can be targeted more effectively.


Asunto(s)
Trastornos Relacionados con Cocaína/complicaciones , Trastornos de la Personalidad/complicaciones , Trastornos de la Personalidad/diagnóstico , Adulto , Afecto/efectos de los fármacos , Anciano , Ansiedad/diagnóstico , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Circulación Cerebrovascular , Cocaína/farmacología , Depresión/diagnóstico , Conducta Exploratoria/efectos de los fármacos , Lóbulo Frontal/irrigación sanguínea , Humanos , Masculino , Persona de Mediana Edad , Motivación , Inventario de Personalidad , Automedicación , Índice de Severidad de la Enfermedad , Exametazima de Tecnecio Tc 99m , Tomografía Computarizada de Emisión de Fotón Único
17.
J Consult Clin Psychol ; 67(4): 547-54, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10450625

RESUMEN

Adult smokers (N = 253) without clinically significant depression were randomized on a double-blind basis to receive fluoxetine (30 or 60 mg daily) or a placebo for 10 weeks in combination with cognitive-behavioral therapy (CBT). It was predicted that fluoxetine would selectively benefit smokers with higher baseline depression, nicotine dependence, and weight concern and lower self-efficacy about quitting smoking. Among those who completed the prescribed treatment regimen, baseline depression scores moderated the treatment response. Logistic regression analyses showed that 1 and 3 months after the quit date, fluoxetine increased the likelihood of abstinence, as compared with placebo, among smokers with minor depression but not among those with little or no depression. Results suggests that, as an adjunct to CBT, fluoxetine enhances cessation by selectively benefiting medication-compliant smokers who display even subclinical levels of depression.


Asunto(s)
Antidepresivos de Segunda Generación/administración & dosificación , Fluoxetina/administración & dosificación , Cese del Hábito de Fumar/psicología , Adolescente , Adulto , Anciano , Terapia Cognitivo-Conductual , Terapia Combinada , Depresión/diagnóstico , Depresión/terapia , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
18.
Int J Exp Pathol ; 79(3): 141-9, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9741356

RESUMEN

In the rat, a single subcutaneous injection of sodium dichromate (20 mg/kg) causes acute renal injury and significant polyuria, proteinuria, and glycosuria (peaking 2-3 days after treatment, and returning to normal by day 5) without any changes in the plasma levels of protein, glucose, and glycated haemoglobin. Surprisingly, the percentage levels of glycated plasma total proteins and albumin (assayed by boronate affinity chromatography) transiently and significantly decrease during recovery from proteinuria (days 4 and 10 after treatment) and were found in the normal range of values by day 18. These changes are concomitant with a significant increase in the percentage level of glycated albumin in urine. Constancy of total plasma protein and the temporal pattern of levels of glycation suggest that changes in the percentage values of glycated proteins are secondary to a transient selective loss of glycated plasma proteins in urine.


Asunto(s)
Lesión Renal Aguda/sangre , Proteínas Sanguíneas/metabolismo , Proteinuria/sangre , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/orina , Animales , Glucemia/metabolismo , Cromatos , Electroforesis en Gel de Poliacrilamida , Hemoglobina Glucada/metabolismo , Glicosilación , Masculino , Proteinuria/inducido químicamente , Ratas , Ratas Sprague-Dawley , Albúmina Sérica/metabolismo
20.
Minerva Chir ; 53(3): 129-34, 1998 Mar.
Artículo en Italiano | MEDLINE | ID: mdl-9617107

RESUMEN

BACKGROUND: Surgeons variously estimate usage of mechanical staplers in digestive surgery especially about the increase of the incidence of late complications like stricture (as some authors refer). We report a histomorphological aid to the comparison of staplers and hand-sewn sutures. Our aim was to observe at long term the healing process in the sutured tissue in the canine gastro-enteric tract. METHODS: We describe three histological pieces: one manual suture in a dog which was euthanatized and necropsied 5 months after operation and two mechanical sutures performed in two different dogs: one died because of a gastric torsion 18 months after the operation while the other was euthanatized 5 months after the operation. The histomorphological study has been carried out with a peculiar cutting (Exact) and including method which lets the staples in situ. RESULTS AND CONCLUSIONS: Compared analysis showed that cicatrization goes on better in stapled than in hand sutured tissue.


Asunto(s)
Anastomosis Quirúrgica/efectos adversos , Procedimientos Quirúrgicos del Sistema Digestivo , Engrapadoras Quirúrgicas , Técnicas de Sutura , Animales , Constricción Patológica , Perros , Estudios de Evaluación como Asunto , Estudios de Seguimiento , Intestino Delgado/anatomía & histología , Intestino Delgado/patología , Intestino Delgado/cirugía , Estómago/anatomía & histología , Estómago/patología , Estómago/cirugía , Factores de Tiempo , Cicatrización de Heridas
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