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1.
Phys Chem Chem Phys ; 24(39): 24487-24494, 2022 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-36193701

RESUMEN

In this paper, we address the unique nature of fully textured, high surface-to-volume 3C-SiC films, as produced by intrinsic growth anisotropy, in turn generated by the high velocity of the stacking fault growth front in two-dimensional (111) platelets. Structural interpretation of high resolution scanning electron microscopy and transmission electron microscopy data is carried out for samples grown in a hot-wall low-pressure chemical vapour deposition reactor with trichlorosilane and ethylene precursors, under suitable deposition conditions. By correlating the morphology and the X-ray diffraction analysis we also point out that twinning along (111) planes is very frequent in such materials, which changes the free-platelet configuration.

2.
Cell Mol Life Sci ; 64(9): 1158-68, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17417742

RESUMEN

In this study we have assessed the effect of testosterone (T), dihydrotestosterone (DHT) and 5alphaandrostan-3alpha, 17beta-diol (3alpha-diol) therapies on diabetic neuropathy. Diabetes was induced in adult male rats by the injection of streptozotocin and resulted in decreased T and increased 3alpha-diol levels in plasma and in decreased levels of pregnenolone and DHT in the sciatic nerve. Moreover, a reduced expression of the enzyme converting Tinto DHT (i.e., the 5alpha-reductase) also occurs at the level of sciatic nerve, suggesting that the decrease of DHT levels could be due to an impairment of this enzyme. Chronic treatment for 1 month with DHT or 3alpha-diol increased tail nerve conduction velocity and partially counteracted the increase of thermal threshold induced by diabetes. Treatment with DHT increased tibial Na(+),K(+)-ATPase activity and the expression of myelin protein P0 in the sciatic nerve.DHT, 3alpha-diol and T reversed the reduction of intra-epidermal nerve fiber density induced by diabetes. These observations indicate that T metabolites can reverse behavioral, neurophysiological, morphological and biochemical alterations induced by peripheral diabetic neuropathy.


Asunto(s)
Diabetes Mellitus Experimental/fisiopatología , Neuropatías Diabéticas/prevención & control , Dihidrotestosterona/uso terapéutico , Fármacos Neuroprotectores/uso terapéutico , Testosterona/uso terapéutico , Anabolizantes/uso terapéutico , Androstano-3,17-diol/uso terapéutico , Animales , Masculino , Ratas , Ratas Sprague-Dawley
3.
Neuroscience ; 144(4): 1293-304, 2007 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-17187935

RESUMEN

One important complication of diabetes is damage to the peripheral nervous system. However, in spite of the number of studies on human and experimental diabetic neuropathy, the current therapeutic arsenal is meagre. Consequently, the search for substances to protect the nervous system from the degenerative effects of diabetes has high priority in biomedical research. Neuroactive steroids might be interesting since they have been recently identified as promising neuroprotective agents in several models of neurodegeneration. We have assessed whether chronic treatment with progesterone (P), dihydroprogesterone (DHP) or tetrahydroprogesterone (THP) had neuroprotective effects against streptozotocin (STZ)-induced diabetic neuropathy at the neurophysiological, functional, biochemical and neuropathological levels. Using gas chromatography coupled to mass-spectrometry, we found that three months of diabetes markedly lowered P plasma levels in male rats, and chronic treatment with P restored them, with protective effects on peripheral nerves. In the model of STZ-induced of diabetic neuropathy, chronic treatment for 1 month with P, or with its derivatives, DHP and THP, counteracted the impairment of nerve conduction velocity (NCV) and thermal threshold, restored skin innervation density, and improved Na(+),K(+)-ATPase activity and mRNA levels of myelin proteins, such as glycoprotein zero and peripheral myelin protein 22, suggesting that these neuroactive steroids, might be useful protective agents in diabetic neuropathy. Interestingly, different receptors seem to be involved in these effects. Thus, while the expression of myelin proteins and Na(+),K(+)-ATPase activity are only stimulated by P and DHP (i.e. two neuroactive steroids interacting with P receptor, PR), NCV, thermal nociceptive threshold and intra-epidermal nerve fiber (IENF) density are also affected by THP, which interacts with GABA-A receptor. Because, a therapeutic approach with specific synthetic receptor ligands could avoid the typical side effects of steroids, future experiments will be devoted to evaluating the role of PR and GABA-A receptor in these protective effects.


Asunto(s)
Neuropatías Diabéticas/tratamiento farmacológico , Fármacos Neuroprotectores/farmacología , Nervios Periféricos/efectos de los fármacos , Nervios Periféricos/metabolismo , Progesterona/farmacología , 20-alfa-Dihidroprogesterona/farmacología , 20-alfa-Dihidroprogesterona/uso terapéutico , Animales , Diabetes Mellitus Experimental/complicaciones , Neuropatías Diabéticas/fisiopatología , Neuropatías Diabéticas/prevención & control , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/fisiología , Masculino , Proteínas de la Mielina/genética , Conducción Nerviosa/efectos de los fármacos , Conducción Nerviosa/fisiología , Fármacos Neuroprotectores/uso terapéutico , Umbral del Dolor/efectos de los fármacos , Umbral del Dolor/fisiología , Nervios Periféricos/fisiopatología , Pregnanolona/farmacología , Pregnanolona/uso terapéutico , Progesterona/sangre , Progesterona/uso terapéutico , ARN Mensajero/efectos de los fármacos , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores de GABA-A/efectos de los fármacos , Receptores de GABA-A/metabolismo , Recuperación de la Función/efectos de los fármacos , Recuperación de la Función/fisiología , Células Receptoras Sensoriales/efectos de los fármacos , Células Receptoras Sensoriales/metabolismo , Piel/inervación , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Resultado del Tratamiento
5.
J Clin Endocrinol Metab ; 86(2): 608-12, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11158017

RESUMEN

The psychological symptoms assessed with a validated psychometric scale, SCL-90, were significantly higher in postmenopausal women (PMW; 60 subjects) than in premenopausal women (20 subjects). In the same PMW, the activity of the dopaminergic system, assessed with the PRL response to the dopamine-blocking agent sulpiride, was significantly lower than that in premenopausal women. During a period of 12 weeks the 60 PMW were randomly divided into 3 groups: no treatment (group A; n = 20), treatment with estradiol (E(2)) alone (patches with a E(2) release of 50 microg/24 h; group B; n = 20), and treatment with hormonal replacement therapy [estradiol valerate (EV) at a daily dose of 2 mg for 11 days and EV at the same daily doses plus cyproterone acetate (CPA) at a daily dose of 1 mg/day for 10 days; group C; n = 20). At the 12th week of the observation, only in group C women were the psychological symptoms significantly decreased, and the indirect evaluation of the dopaminergic system activity through PRL response to sulpiride showed a significant increase. During the same period, no changes in testosterone levels were observed in any group of PMW, whereas a significant increase in E(2) levels was found in both groups B and C. Although it is likely that the improvement in psychological symptoms with EV and CPA was due to progestin, we cannot rule out the possibility that greater estrogen exposure may have played a role.


Asunto(s)
Antagonistas de Andrógenos/uso terapéutico , Acetato de Ciproterona/uso terapéutico , Dopamina/fisiología , Estradiol/análogos & derivados , Terapia de Reemplazo de Estrógeno , Trastornos Mentales/tratamiento farmacológico , Posmenopausia/psicología , Adulto , Ansiedad , Área Bajo la Curva , Depresión , Estradiol/administración & dosificación , Femenino , Humanos , Trastornos Mentales/etiología , Persona de Mediana Edad , Posmenopausia/fisiología , Premenopausia/fisiología , Premenopausia/psicología , Prolactina/sangre , Prolactina/metabolismo , Pruebas Psicológicas , Psicometría , Reproducibilidad de los Resultados , Sulpirida
6.
J Pineal Res ; 21(4): 239-42, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8989723

RESUMEN

Several experimental studies have shown that melatonin has an oncostatic action, either by stimulating host antitumor immune defenses or by directly inhibiting the growth of some cancer histotypes, including melanoma. Our previous clinical studies demonstrated that melatonin may induce stabilization of the disease in untreatable metastatic solid tumor patients, and these results have been confirmed by others, at least in patients with metastatic melanoma. On the contrary, at present there are no data related to the possible efficacy of melatonin as an adjuvant endocrine therapy. This study was performed to investigate the impact of melatonin therapy on the disease-free survival (DFS) in melanoma patients surgically treated for regional node recurrence. The study included 30 node-relapsed melanoma patients, who were randomized to receive no treatment or adjuvant therapy of melatonin (20 mg/day orally in the evening) every day until disease progression. After a median follow up of 31 months, the percent of DFS was significantly higher in melatonin-treated individuals than in controls. The DFS curve was also significantly longer in melatonin group than in controls. No melatonin-related toxicity was observed. This preliminary study suggests that an adjuvant endocrine therapy with melatonin may be effective in preventing disease progression in node-relapsed melanoma patients.


Asunto(s)
Ganglios Linfáticos/efectos de los fármacos , Melanoma/tratamiento farmacológico , Melatonina/uso terapéutico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Glándula Pineal , Adulto , Anciano , Anciano de 80 o más Años , Quimioterapia Adyuvante , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Ganglios Linfáticos/patología , Ganglios Linfáticos/cirugía , Metástasis Linfática/patología , Masculino , Melanoma/patología , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Recurrencia , Resultado del Tratamiento
8.
Mycoses ; 38(5-6): 229-30, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8531938

RESUMEN

Trichophyton soudanense is an anthropophilic dermatophyte originating in Africa. Over the last 30 years sporadic cases have been reported in countries that had colonial relations with the endemic areas. In recent times, as a result of growing racial mixing linked to migratory movements, this strain has become increasingly integrated with the species most commonly responsible for dermatophytoses. This phenomenon has occurred, although only recently, in Italy too, where there has been a heavy influx of foreign immigrants over the last few years.


Asunto(s)
Tiña/diagnóstico , Trichophyton , Adulto , Angola/etnología , Antifúngicos/uso terapéutico , Pie/patología , Griseofulvina/uso terapéutico , Cabeza/patología , Humanos , Italia/epidemiología , Masculino , Persona de Mediana Edad , Naftalenos/uso terapéutico , Cuello/patología , Terbinafina , Tiña/tratamiento farmacológico , Tiña/epidemiología
9.
G Ital Dermatol Venereol ; 125(9): 397-9, 1990 Sep.
Artículo en Italiano | MEDLINE | ID: mdl-1706683

RESUMEN

A case of cutaneous angiogenesis, probably induced by tumour angiogenic factors (TAF), is described. The patient, a 39-year-old female, affected by a vulvar squamous cell carcinoma, developed some erythematoangiomatous lesions on the lower abdominal quadrants, contiguously to the tumour. Histopathologically, the lesions were characterized by vascular neoformation in the superficial dermis and a slight lymphohistiocytic lesions resolved after the polychemotherapy which preceded enlarged vulvectomy. This supports the hypothesis of a close correlation between neoangiogenesis and TAF.


Asunto(s)
Carcinoma de Células Escamosas/complicaciones , Neovascularización Patológica , Piel/irrigación sanguínea , Neoplasias de la Vulva/complicaciones , Adulto , Femenino , Humanos
10.
Minerva Psichiatr ; 31(3): 121-8, 1990.
Artículo en Italiano | MEDLINE | ID: mdl-2283943

RESUMEN

The study examines the relative influence of sundry psychological risk factors on the various forms of angina pectoris found in two groups of women with classic angina pains attributable in one group to critical organic lesions of the coronary arteries and in the other to functional spasm. In all 81 women were examined and no significant difference was found between the two groups.


Asunto(s)
Angina de Pecho/psicología , Trastorno Depresivo/complicaciones , Trastornos Neuróticos/complicaciones , Dolor/etiología , Humanos , Masculino , Persona de Mediana Edad , Dolor/psicología , Factores de Riesgo
11.
G Ital Dermatol Venereol ; 125(6): 271-3, 1990 Jun.
Artículo en Italiano | MEDLINE | ID: mdl-2279755

RESUMEN

A case of a 49-year-old woman affected by wide ulcerations on the face which have been caused by the patient herself, as she has admitted, is reported. The lesions were strictly limited to the area of innervation of the first and second branch of the trigeminal nerve. The patient presented parasthesias and analgesia in the trigeminal area as the consequence of a neurosurgical operation. She also suffered from important psychosis. All these elements enable us to diagnose "trigeminal trophic ulcers". The pathogenesis of this syndrome is discussed.


Asunto(s)
Dermatosis Facial/etiología , Úlcera Cutánea/etiología , Nervio Trigémino , Enfermedades de los Nervios Craneales/etiología , Femenino , Humanos , Persona de Mediana Edad , Automutilación
12.
Arch Dermatol ; 125(11): 1540-2, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2554818

RESUMEN

The chemotherapy of leishmaniasis is still far from satisfactory. Itraconazole, one of the most recent azole antifungal agents, appears to be well tolerated in man. Two patients with cutaneous leishmaniasis (Leishmania tropica), contracted in Saudi Arabia, were treated orally for 2 months with itraconazole (100 mg/d). Both recovered without side effects or abnormalities in their main biologic parameters.


Asunto(s)
Antiprotozoarios/uso terapéutico , Cetoconazol/análogos & derivados , Leishmaniasis/tratamiento farmacológico , Adulto , Estudios de Seguimiento , Humanos , Itraconazol , Cetoconazol/uso terapéutico , Masculino
13.
G Ital Dermatol Venereol ; 124(6): 277-9, 1989 Jun.
Artículo en Italiano | MEDLINE | ID: mdl-2698380

RESUMEN

Three cases with coexisting psoriasis and bullous pemphigoid are reported and the possible etiopathogenetic relationships between the two diseases are discussed.


Asunto(s)
Penfigoide Ampolloso/complicaciones , Psoriasis/complicaciones , Enfermedades Cutáneas Vesiculoampollosas/complicaciones , Anciano , Humanos , Masculino , Persona de Mediana Edad , Penfigoide Ampolloso/etiología
14.
G Ital Dermatol Venereol ; 124(4): 163-5, 1989 Apr.
Artículo en Italiano | MEDLINE | ID: mdl-2807395

RESUMEN

The Authors describe the case of a 23 year old woman affected by lichen aureus in a zosteriform pattern localized at the right side of the trunk.


Asunto(s)
Enfermedades de la Piel , Adulto , Enfermedad Crónica , Diagnóstico Diferencial , Femenino , Humanos , Púrpura/diagnóstico , Piel/patología , Enfermedades de la Piel/diagnóstico , Enfermedades de la Piel/patología
16.
Int Clin Psychopharmacol ; 3(3): 245-53, 1988 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3153712

RESUMEN

Unlike conventional antidepressants, rolipram stimulates both the presynaptic as well as the postsynaptic component of monoaminergic transmission. Several double-blind comparative trials are on the way to assess the clinical efficacy and safety of this novel compound. The present study was a randomized double-blind double-dummy comparison with imipramine in inpatients with major, "minor" and atypical depressions (DSM III). Results show no relevant differences between rolipram and imipramine regarding efficacy and safety.


Asunto(s)
Antidepresivos , Trastorno Depresivo/tratamiento farmacológico , Hospitalización , Imipramina/uso terapéutico , Pirrolidinonas/uso terapéutico , Adolescente , Adulto , Anciano , Trastorno Depresivo/psicología , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Rolipram
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