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41.
BACKGROUND AND OBJECTIVES: Oxidative stress can induce cell mutations or proliferation which then can progress to carcinogenesis or remodeling. The same oxidative stress-mediated mechanism could participate in prostate cell proliferation and remodeling present in benign prostatic hyperplasia (BPH). Doxazosin induces prostate epithelial and stromal cell apoptosis through production of transforming growth factor-beta (TGF-beta), but cellular mechanisms are not completely clarified. In 10 prostate samples from BPH untreated patients who underwent TUR, we have assessed the gene and protein expression of: p22(phox) (subunit of NAD(P)H oxidase essential for O(2)(-) production); heme oxygenase-1 (HO-1) (induced by oxidative stress and antiapoptotic); TGF-beta (inhibitor of prostatic epithelial and stromal cell growth); the in vitro effect of doxazosin on expression of these markers. METHODS: RT-PCR and Western blot with specific primers and antibodies. p22(phox), HO-1 and TGF-beta were quantified by the ratio between their PCR and Western blot products and GAPDH. RESULTS: Doxazosin significantly reduced p22(phox) gene and protein expression (0.61 +/- 0.04 vs. 0.36 +/- 0.04 d.u., p < 0.0002; 0.85 +/- 0.03 vs. 0.47 +/- 0.03, p < 0.0001, respectively). Doxazosin concentration dependently reduced HO-1 gene and protein expression (0.57 +/- 0.07 vs. 0.49 +/- 0.06 d.u. (1 microM) p < 0.04, vs. 0.22 +/- 0.08 (10 microM) p < 0.0001; 0.78 +/- 0.04 vs. 0.44 +/- 0.1 (10 microM) p < 0.003 respectively) and increased TGF-beta protein expression (0.58 +/- 0.05 vs. 0.74 +/- 0.16 (1 microM) n.s. vs. 0.81 +/- 0.07 (10 microM) p < 0.01). CONCLUSIONS: Induction of oxidative stress-related proteins seems to be involved in the prostate cell proliferation and remodeling present in BPH. Doxazosin may reduce oxidative stress through reduction of p22(phox). Surprisingly, HO-1, which is induced and protected by oxidative stress, is also reduced by doxazosin. HO-1 is a potent antiapoptotic factor and downregulator of TGF-beta. From the results of this preliminary study it could be proposed that the proapoptotic effect of doxazosin could be mediated, at least in part, through the contemporary inhibition of HO-1.  相似文献   
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Eighty-six patients with locally advanced, high-grade soft tissue sarcomas of the extremities were studied prospectively in order to determine the efficacy of hyperthermic perfusion (HP) or hyperthermic antiblastic perfusion (HAP) as the first step of a combined multimodality therapy. The immediate response was evaluated in terms of tumor regression, and results confirmed the in vivo sensitivity of human sarcomas to the selective antineoplastic action of heat alone or combined with drugs (melphalan, actinomycin D, and cis-platinum). HAP has been shown to be simpler and safer than HP, and it is now currently routinely employed. As far as the long-term cure is concerned, all the patients have been evaluated for functional results, locoregional control, and survival, according to the different treatment schedules. The first clinical trials employed HP or HAP followed by delayed surgery alone. In 11 of 17 evaluable patients treated with HP, and in 17 of 29 treated with HAP, conservative surgery could be performed. A high incidence of locoregional relapse (24%) occurred, with low overall survival rates: 50.1% and 31.7% at 5 and 10 years after HP plus surgery, and 47.9% after HAP plus surgery at both 5 and 10 years. The protocol was, therefore, modified to include continuous intraarterial infusion of Adriamycin® (ADR) (17 patients) or radiotherapy (9 patients) before surgery. The results obtained thus far may be summarized as follows: (a) conservative surgery with functional limb-salvage was possible in all patients; (b) the percentage of locoregional failure decreased to approximately 12% after HAP + ADR infusion + excision, the 5- and 10-year overall survival rates both being 77.6 %, and the 5- and 10-year disease-free rates both being 57.8%; (c) no local recurrences occurred in the group treated with HAP + radiotherapy + excision with a 5-year overall survival rate of 71.5% and a 5-year disease-free rate of 50.4%. In conclusion, the combined multimodality approaches employed appear to have improved both functional results and long-term cure, even though these must be further confirmed on a larger series of patients.
Resumen Ochenta y seis pacientes con sarcomas de los tejidos blandos de las extremidades, de alto grado histológico, e invasión local avanzada fueron estudiados en forma prospectiva con el objeto de determinar la eficacia de la perfusión hipertérmica (PH) o la perfusión hipertérmica antiblástica (PHA) como primer paso dentro de una terapia combinada multimodal.La respuesta inmediata fue valorada en términos de la regresión tumoral, y los resultados confirmaron la sensibilidad in vivo de los sarcomas humanos a la acción antineoplásica selectiva del calor sólo o combinado con drogas (melfalán, actinomicina D, y cis-platino). La PHA ha demostrado ser más sencilla y más segura que la PH y actualmente es utilizada en forma rutinaria.En lo referente a curación a largo plazo, todos los pacientes han sido evaluados en cuanto a resultados funcionales, control locorregional, y supervivencia, de acuerdo a los diferentes programas terapéuticos.En los primeros ensayos clínicos se utilizó PH o PHA seguida de cirugía solamente. En 11 de 17 pacientes valorables tratados con PH y 17 con PHA, fue posible realizar cirugía conservadora. Se presentó una incidencia alta de relapso locorregional (24%), con tasas bajas de supervivencia global: 50.1% y 31.7% a 5 y 10 años con PH y cirugía, y 47.9% con PHA y cirugía tanto a 5 como a 10 años.El protocolo fue consecuentemente modificado para incluir una infusión intraarterial continua de Adriamicina® (ADR) (17 pacientes) o radioterapia (9 pacientes) antes de la cirugía.Los resultados logrados hasta el momento pueden ser resumidos así: (a) la cirugía conservadora con salvamento del miembro fue posible en la totalidad de los pacientes; (b) el porcentaje de falla locorregional disminuyó aproximadamente 12% después de PHA + infusión de ADR + resección, con supervivencias globales a 5 y 10 años de 77.6%, y tasas de estado libre de enfermedad a 5 y 10 años de 57.8%; (c) no se presentaron recurrencias locales en el grupo tratado con PHA + radioterapia + resección, con una tasa de supervivencia global a 5 años de 71.5% y una tasa de estado libre de enfermedad a 5 años de 50.4%.En conclusión, los aproches con terapia combinada multimodal empleados parecen haber mejorado tanto los resultados funcionales como las tasas de curación a largo plazo, aunque estos resultados aún deben ser reconfirmados en una serie mayor de pacientes.

Résumé Une étude prospective concernant 86 malades qui présentaient un sarcome des parties molles des membres de stade évolutif avancé a été entreprise pour déterminer l'efficacité de la perfusion hyperthermique ou de la perfusion hyperthermique antiblastique en tant que première étape d'un traitement à modalités multiples.La réponse immédiate a été appréciée en fonction de la régression tumorale. Les résultats ont confirmé la sensibilité in vivo des sarcomes humains à l'action antinéoplasique sélective de la chaleur employée isolemment ou combinée avec des drogues (melphalan, actinomycine D, et cis-platinum). La perfusion hyperthermique antiblastique s'est montrée plus simple et plus sûre que la perfusion hyperthermique, et de ce fait est devenue une méthode thérapeutique normalement employée.Pour apprécier l'action thérapeutique à long terme tous les malades ont été étudiés en tenant compte des résultats fonctionnels, du contrôle loco-régional, et de la survie obtenus selon les différentes thérapeutiques appliquées.Les premiers essais ont eu recours à l'hyperthermie thermique ou à l'hyperthermie thermique antiblastique suivie d'une intervention chirurgicale. Chez 11 des 17 malades traités par l'hyperthermie thermique, et chez 17 des 29 malades soumis à l'hyperthermie antiblastique le traitement chirurgical conservateur a pu être réalisé. Les résultats furent les suivants: fréquence importante des récidives loco-régionales (24%); taux global de survie bas: 50.1% et 31.7% à 5 ans et 10 ans après perfusion hyperthermique suivie de chirurgie, ce taux étant de 47.9% après perfusion hyperthermique antiblastique suivie de chirurgie à 5 ans et 10 ans.En fonction de ces résultats le protocole thérapeutique fut modifié en y ajoutant une transfusion intra-artérielle continue d'Adriamycine® (17 malades) ou de la radiothérapie (9 malades) avant l'intervention.Les résultats obtenus à ce jour peuvent se résumer ainsi: (a) la chirurgie conservatrice permettant de sauver un membre fonctionnel est toujours possible; (b) la poucentage d'échec régional décroit environ jusqu' à 12% après perfusion hyperthermique antiblastique associée à la perfusion d'Adriamycine® et l'excision, le taux global de survie à 5 ans et 10 ans étant de 77.6%, le taux d'absence de la maladie à 5 ans et 10 ans étant de 57.8%; (c) aucune récidive locale n'est survenue dans le groupe traité par perfusion hyperthermique antiblastique associé à la radiothérapie et à l'exérèse, le taux global de survie à 5 ans étant de 71.5% et le taux d'absence de la maladie à 5 ans étant de 50.4%.En conclusion le traitement qui a été employé associant plusieurs modalités thérapeutiques a entrainé une amélioration des résultats fonctionnels et de la cure à long terme encore que ce fait demande a été confirmé par une étude étendue à un plus grand mombre de malades.


Supported by Special Project Hyperthermia from the Italian Ministry of Health.  相似文献   
44.
A 55-year-old man presented to our Department with a 10-year history of coarsening of the facial features. The soft tissue of the forehead had become progressively thickened and corrugated, resulting in marked, hard-elastic asymmetrical convolutions involving the underlying eyelids, with partial reduction of the visual field ( Fig. 1a,b ). The patient also exhibited moderately prominent nasolabial folds, pachydermia of the hands and feet without nail changes, significant seborrhoea and palmo-plantar hyperhydrosis.
Figure 1 Open in figure viewer PowerPoint (a) Normal aspect of the face (before pulmonary disease); (b) definitive changes in the face: asymmetrical convolutions of the forehead, hypertrophy of the eyelids and prominent nasolabial folds  相似文献   
45.
Exogenous ochronosis is a paradoxical hyper-pigmentation of the skin caused by the long-term use of hydroquinone-containing bleaching creams. Ochronosis is an uncommon condition characterized by yellow-brown pigmented deposits in the dermis. We report two cases of exogenous ochronosis in two female patients of the sub-Saharan African population. The lesions were characterized by an asymptomatic hyper-pigmentation of the face with gradually progressive blue-black macular patches, and in case no. 2, in addition to dyschromic lesions, striae atrophicae were present. This phenomenon is the outcome of the use of skin care products containing high concentrations of hydroquinone- and glucocorticoid-based products, and, in addition, certain modalities in the use of bleaching products are likely to facilitate complications.  相似文献   
46.
AIM: We present a case of squamous-cell carcinoma developing within perianal lichen planus. This is a chronic or recurrent cutaneous and/or mucosal dermatosis affecting less than 1 percent of the population. Neoplastic degeneration of cutaneous lichen planus is rare; only one case of squamous-cell carcinoma developing within perianal lichen planus has been described up until now in the international literature. CASE REPORT: Our case involved a 68-year-old woman with chronic, long-term lichen planus spreading all over the vulva and perianal region and the mucosa of the anal canal, where squamous-cell carcinoma developed within the perianal lichen planus. Treatment consisted of wide, circular excision of the perianal skin and mucosectomy of the anal canal up to as far as 1 cm above the dentate line. Reconstruction was performed by means of two V-Y bilateral subcutaneous flaps. CONCLUSION: Wide excision was performed not only to remove the squamous-cell carcinoma but also the lichen planus to prevent recurrence of metachronous or synchronous squamous-cell carcinoma. Follow-up at one year after surgery showed no local recurrence of either lichen planus or squamous-cell carcinoma, which suggests that surgical removal should be the therapy of choice for long-term, chronic perianal lichen planus that has proved to be resistant to medical therapy.  相似文献   
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48.
BACKGROUND: Spontaneous variations in the chronic stimulation threshold were widely investigated in the last few years and formed the basis of the safety margin concept of stimulation energy. The dynamic variability of sensitivity, particularly in the atrium, is less studied and, in the literature, contrasting data are present about the actual entity of these variations. A 2:1 safety margin is still recommended by many authors, although some papers reported that this value was inadequate to guarantee a correct sensing function. AIM OF THE STUDY: We evaluated daily variability of atrial sensitivity (AS) in patients implanted with the Cosmos 3 DDD cardiac pacemaker, with a special algorithm that continuously measures the minimum-maximum sensitivity values in atrium or in the ventricle during a 12-h sampling period. MATERIALS AND METHODS: 34 patients, 20 males and 14 females, with a mean age of 72+/-5 years, were implanted with a Cosmos 3 DDD pacemaker (PM). The indication to implant a PM was sick sinus syndrome in 21 patients and a high degree of AV block in 13 patients. Atrial bipolar leads were always employed. At 1, 2, 3 and 6 months after the implant, we analyzed the minimum-maximum values of atrial sensitivity for the last 12-h. This analysis was performed in the late afternoon. RESULTS: The mean AS varied more than threefold, from a mean minimum of 0.68 to a mean maximum value of 2.19 mV at 1 month, from 0.68 to 2.21 mV at 2 months, from 0.69 to 2.19 mV at 3 months and from 0.67 to 2.17 mV at 6 months, without significant differences among the four follow-up controls. In seven patients, there was a fourfold variation, while the variation was fivefold in five patients. CONCLUSION: In conclusion, from our data, we can confirm that atrial sensitivity may vary widely during the day and, consequently, we recommend that a 3:1 safety margin should be programmed and the recommended 2:1 ratio should be abandoned. Moreover, at implant, particular attention should be paid to obtaining the best atrial signal amplitude, at least threefold higher than the highest sensitivity value available in the implanted PM. To achieve this goal and to obviate to the oversensing phenomena, bipolar leads are preferable to unipolar leads.  相似文献   
49.
Ninety-two patients affected by chronic cerebrovasculopathy were treated with cytidine diphosphate choline (CDP-choline) 1000 mg/day i.m. or with placebo, in a double-blind study. Two cycles of therapy of 4 weeks each were performed, with an interval of 1 week. There were 46 patients in each group with chronic cerebrovascular diseases, and the two groups were comparable as far as mental deterioration was concerned. The following psychometric tests were administered: Toulouse-Piéron (attention to non-verbal stimuli), Randt Memory test (memory), Sandoz Clinical Assessment of Geriatrics (SCAG, measurement of the behavioral and emotional control). The comparison between the two groups revealed significant improvements in the CDP-choline group compared with the placebo group in some of the attention capabilities (decrease in the number of wrong answers at the Toulouse-Piéron test), of the mnemonic capabilities ('General Information' subtest of Randt Memory test) and behavioral capabilities (SCAG 'affective disturbances' score). No side-effects were detected in the CDP-choline group.  相似文献   
50.
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