Tobacco in adolescence: importance to knowledge the health hazards and preventive measures

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Drogas, sujeito e proibicionismo: uma discussão sobre os modelos de atenção aos usuários de drogas

Pós-graduação em Psicologia - FCLAS

Clinicopathologic and immunohistochemical features of oral neurofibroma

Objective. The purposes of this study were to assess clinical, histopathological and immunohistochemical features of 22 oral neurofibromas (NFs) and discuss with previously described literature, addressing the main aspects regarding the differential diagnosis. Materials and methods. Immunohistochemical reactions included S-100, CD34, GLUT-1, EMA, Ki-67, p53 and Collagen IV and histochemical reactions for Alcian blue. Results. Clinically, the preferential location was the maxillary bones, tongue and buccal mucosa. Microscopically, widely spread spindle-shaped cells with scant cytoplasm and elongated nuclei were observed. Immunostaining revealed that the tumor cells weakly expressed GLUT-1, Collagen IV, Ki-67 and p53. They were variably positive for CD34, S-100 protein and membrane epithelial antigen (EMA). Conclusions. The different types of nerve sheath cells observed in the present series reinforce the presence of heterogeneous population in NFs. The strong positivity for S-100 suggests that the lesions were more composed by S-100-positive Schwann cells than other cells. Besides, the high number of CD34-positive cells suggests that this marker can be useful for the differential diagnosis of NFs against PEN, traumatic neuromas and Schwannomas. Finally, the low immunostaining for p53 and Ki-67 may indicate that NFs massively composed by S-100-positive Schwann cells present low potential of aggressiveness and malignant transformation.

Motor Neuron Disease and Acquired Axonal Neuropathy Association in HIV Infection: Case Report and Update

Background: A possible viral etiology has been documented in the genesis of motor neuron disorders and acquired peripheral neuropathies, mainly due to the vulnerability of peripheral nerves and the anterior horn to certain viruses. In recent years, several reports show association of HIV infection with Amyotrophic Lateral Sclerosis Syndrome, Motor Neuron Diseases and peripheral neuropathies. Objective: To report a case of an association between Motor Neuron Disease and Acquired Axonal neuropathy in HIV infection, and describe the findings of neurological examination, cerebrospinal fluid, neuroimaging and electrophysiology. Methods: The patient underwent neurological examination. General medical examinations were performed, including, specific neuromuscular tests, analysis of cerebrospinal fluid, muscle biopsy and imaging studies. Results and Discussion: The initial clinical presentation of our case was marked by cramps and fasciculations with posterior distal paresis and atrophy in the left arm. We found electromyography tracings with deficits in the anterior horn of the spinal cord and peripheral nerves. Dysphagia and release of primitive reflexes were also identified. At the same time, the patient was informed to be HIV positive with high viral load. He received antiretroviral therapy, with load control but with no clinical remission. Conclusion: Motor Neuron disorders and peripheral neuropathy may occur in association with HIV infection. However, a causal relationship remains uncertain. It is noteworthy that the antiretroviral regimen may be implicated in some cases.

Oestrogen receptor beta in adenoid cystic carcinoma of salivary glands

Aims: This study aimed to describe the expression of oestrogen receptor (ER)alpha, ER beta and aromatase in salivary gland adenoid cystic carcinoma (ACC). Methods and results: ER alpha, ER beta and aromatase expression was analysed by immunohistochemistry in tissue microarray blocks from 38 cases of ACC and seven normal salivary glands. The intracellular localization and amount of total protein expression were investigated by immunofluorescence and western blotting in an ACC cell line. Western blotting analysis showed overexpression of ER alpha, ER beta and aromatase in the ACC cell line; however, with immunofluorescence, only ER beta was shown to be expressed in the nucleus. Immunohistochemistry revealed positive nuclear expression of ER beta, positive cytoplasmic expression of aromatase and a lack of ER alpha expression as compared with normal salivary glands. Conclusions: The nuclear expression of ER beta indicates that oestrogen may be active in ACC and possibly able to mediate E2-targeted gene transcription. This study strongly suggests that ER beta may be involved in tumour progression, playing a role in tumour development, and thus corroborating the indication for ER antagonists in the clinical control of ACC. This study opens a new perspective on the potential use of anti-oestrogens and aromatase inhibitors as therapeutic agents against ACC.

Oral leukoplakia manifests differently in smokers and non-smokers

Oral leukoplakias (OL) are potentially malignant lesions that are typically white in color. Smoking is considered a risk factor for developing OL, and dysplastic lesions are more prone to malignant transformation. The aim of this study was to describe the clinical features observed in dysplastic and non-dysplastic OL in both smokers and nonsmokers. A total of 315 cases of OL were retrieved and separated into either dysplastic or non-dysplastic lesions, and these cases were further categorized as originating in either smokers or non-smokers. Frequencies of the type of OL lesion, with respect to whether the patients smoked, were established. The results demonstrated that 131 cases of OL were dysplastic (74 smokers and 57 non-smokers), and 184 were non-dysplastic (96 smokers and 88 non-smokers). For OL cases in smokers for which information about alcohol consumption was also available (84 cases), the results revealed no significant difference in the amount of dysplastic and non-dysplastic lesions. Dysplastic lesions were more frequent in male smokers and in non-smoking females. The median age of smokers with cases of OL was significantly lower than in non-smokers; the lowest median ages were observed for female smokers with dysplastic OL. The most frequent anatomical sites of dysplastic lesions were the floor of the mouth in smokers and the tongue in non-smokers. Dysplastic lesions in smokers were significantly smaller than non-dysplastic lesions in non-smokers. Being a male smoker, being female, being younger, and having smaller lesions were associated with dysplastic features in OL. These clinical data may be important for predicting OL malignant transformation.

On land management: landowners' attitudes to land and farming in Valdera, Tuscany

This thesis aims at explaining the intersecting dynamics of structural changes in agriculture and urbanisation, which involves changes in urban-rural relationships. The research questions are: how and why do landowners differ in their attitudes to land and farming? what are the main implications on rural landscapes and the policy implications? Relationships between urbanisation and agriculture are firstly analysed through a critical literature review; the analysis focuses on the 'landowner' as the key actor who actively takes decisions on the rural landscape From the empirical study – which is based on a Tuscan area (Valdera), and addressed through qualitative methods – a great diversity of landowners' attitudes to land and farming emerge, thus contributing to the agricultural restructuring, such as: 1) the emphasis on recreational function of the countryside for urban people 2) contracting out of land management, especially when landowners live or/and have 'urban' employment 3) the active role of hobby farmers in land management 4) agricultural operations simplification and lack of investments (especially in case of property rights expropriation). The thesis is framed in three papers, with the same methods and research questions. It seems evident that rural landscapes is subjected to functional changes (e.g. residential) and structural changes (landscape polarisation), which requires the need 1) to consider that rural landscape management is increasingly less connected to agricultural production as economic activity; 2) to give a coherence to the range of policy interventions (physical planning, landscape, sectoral).

Valutazione della qualità delle immagini e della dose in multi-slice computed tomography per l'ottimizzazione dei protocolli clinici che impiegano sistemi di modulazione automatica

In questo studio ci siamo proposti di investigare i sistemi di modulazione automatica della dose sui sistemi TC Multislice (Automatic Exposure Control – AEC) da tre diversi produttori, aventi differenti indicatori di qualità delle immagini. Il presente lavoro è stato svolto presso il Servizio di Fisica Sanitaria dell’Azienda Ospedaliera Universitaria - Policlinico Sant’Orsola-Malpighi di Bologna e consiste in un’analisi quantitativa della dose impiegata durante esami di Tomografia Computerizzata Multi-Slice (TCMS) e delle rispettive immagini radiologiche. Le immagini sono state acquisite con : GE LightSpeed VCT 64 e GE LightSpeed 16 (AEC AutomA 3D longitudinale e angolare), Siemens Sensation 16 (AEC CARE Dose 4D combinato), Philips Brilliance 16 e iCT 64 (separati in AEC ZDOM longitudinale e AEC DDOM angolare). Le acquisizioni TCMS sono state effettuate a differenti kV e mA di riferimento, al fine di investigarne gli effetti sulla modulazione, impiegando algoritmi di ricostruzione standard presenti su ogni macchina. Due fantocci antropomorfi simulanti la zona del torace e dell’addome sono stati utilizzati per simulare un paziente standard posizionato come in un esame clinico di routine ; a questo proposito, sono stati impiegati protocolli elicoidali standard con e senza modulazione. Sono inoltre stati testati differenti valori di indice di qualità delle immagini. Il profilo dei mA lungo la lunghezza è stato ottenuto utilizzando ImageJ, un programma open source comunemente utilizzato per l’elaborazione di immagini; i mAs sono stati normalizzati ad un fattore che tiene conto delle differenti geometrie e delle filtrazioni dei diversi scanner tomografici analizzati nell’esperienza. Il rumore è stato valutato tramite la scelta di determinate ROI (Region Of Interest) localizzate in aree il più possibili uniformi disponibili lungo i fantocci. Abbiamo registrato che una variazione del Noise Index o dei mAs di riferimento a seconda della tipologia di macchina analizzata risulta in uno shift dei profili di dose; lo stesso si è verificato quando sono stati cambiato kV o mA nella scout di acquisizione. Sistemi AEC longitudinali e combinati hanno mostrato profili di mAs normalizzati simili tra loro, con valori elevati evidenziati nella zona delle spalle e zona pelvi; sono state osservate differenze del 30-40% tra i differenti scanner tomografici. Solo in un caso di macchina analizzata si è verificato un comportamento opposto rispetto alle altre due tipologie di macchina in esame. A dispetto della differente natura dei sistemi AEC, i risultati ottenuti dai protocolli combinati e longitudinali sono simili tra loro. Il rumore presente nelle immagini è aumentato ad un livello accettabile e la sua uniformità lungo la direzione di scan è migliorata.

La crittografia nel sistema di moneta digitale Bitcoin

In questo documento si presenta lo studio degli algoritmi matematici e crittografici su cui si basa il sistema di moneta digitale Bitcoin, in circolazione dal 2009. Bitcoin è un sistema di cripto valuta elettronica peer-to-peer, ideato da un anonimo conosciuto con lo pseudonimo "Satoshi Nakamoto", i cui principi sono descritti in un documento pubblicato nel 2008 ed ora accessibile in rete. L'utilizzo di Bitcoin permette di effettuare transazioni con sicurezza da un soggetto ad un altro e, grazie a una tecnologia peer-to-peer che opera senza alcuna autorità centrale e intermediari quali banche o istituzioni governative, sia la gestione delle operazioni sia l'emissione di denaro sono svolte per mezzo di un protocollo P2P. Nel corso della trattazione si propone un analisi più tecnica del sistema di gestione e creazione dei Bitcoin e degli strumenti crittografici che hanno permesso l'avvento di questa moneta elettronica decentralizzata.