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C Clemente

Publications and source records attributed to C Clemente.

At least 37 records · Page 2Linked to original sources
PubMed2000

[Multifactorial analysis of therapeutic outcome of pseudophakic retinal detachment surgery].

BACKGROUND: Pseudophakic retinal detachment is one of the most severe complications after cataract surgery and is a common cause of permanently reduced visual acuity. We evaluated parameters predicting reduced functional outcome by a model of stepwise regression analysis. PATIENTS AND METHODS: A series of 102 consecutive patients with pseudophakic retinal detachment were analyzed for various parameters regarding cataract surgery, retinal surgery, and retinal detachment features. First, univariate analysis determined the correlations with reduced functional outcome. Secondly, a stepwise regression model analyzed statistically significant variables for their predictive value of a reduced visual outcome. RESULTS: The overall reattachment rate was 99%. In 69% of the patients there was an improvement of more than two lines at the end of the follow-up period. The most predictive factors for reduced functional outcome were the need for a silicone oil tamponade and the visual acuity prior to retinal detachment surgery. When silicone oil tamponade was not needed, the requirement of more than two retinal surgeries was the most predictive factor for reduced visual outcome. CONCLUSION: In our series the strongest predictive factors for a reduced functional outcome were the necessity of silicone oil, reduced visual acuity at the time of retinal detachment, and the requirement of more than two retinal surgeries. These findings suggest that first-line procedures should not be necessarily minimally invasive measurements but rather procedures that result in a stably attached retina in the first instance without permanent silicone oil tamponade, even if this first operation consists of an extended pars plana vitrectomy.

Adult↗
PubMed2000

Effect of flutamide-induced androgen-receptor blockade on adenylate cyclase activation through G-protein coupled receptors in rat prostate.

The effect of the antiandrogen flutamide on the prostatic vasoactive intestinal peptide (VIP) receptor/effector system was studied in rats. Rats were s.c. injected with a daily dose of flutamide (15 mg/kg B.W.) or vehicle for 14 days. Drug treatment resulted in histological evidence of gland involution and increased plasma membrane fluidity as estimated by fluorescence spectroscopy. The number of VIP receptors and the stimulatory effect of VIP on adenylate cyclase activity in prostatic membranes decreased in flutamide-treated rats. However, the pattern of forskolin stimulation of the enzyme activity was not modified by this drug. Androgen-receptor blockade by flutamide also decreased the prostatic levels of alpha(s,) alpha(i1/2), and alpha(i3/0) G-protein subunits, as estimated by an immunological procedure. Whereas apoptotic DNA fragmentation was evidenced in prostate from 3-day castrated animals, a heterogeneous electrophoretic pattern was observed after flutamide treatment. Thus, androgen-receptor blockade by flutamide results in an important impairment of the components of the VIP receptor/effector system in rat prostate as well as in a modification of their coupling extent, which is presumably due to differences observed in plasma membrane fluidity. These results represent a crosstalk in the prostate between two mechanisms of signal transduction involved in cell proliferation.

Adenylyl Cyclases↗
PubMed1999

Antioxidant effect of short-term hormonal treatment in postmenopausal women.

OBJECTIVES: Recent studies have shown that estrogens alone or in association with progestins can exert an antioxidant effect on Low-Density Lipoprotein (LDL) and lipids of platelet membranes. It has been demonstrated that the oxidative modification of LDLs also involving the formation of lipid peroxides, exerts several biological effects that may contribute to the onset and progression of cardiovascular diseases. Therefore, the aim of our study was to evaluate the effect of short-term treatment with oral estrogens alone and estrogens plus progestin on endogenous and copper-induced serum levels of lipid peroxides in postmenopausal women. METHODS: Thirty-nine postmenopausal women were randomly divided into three groups: group I was treated with oral conjugated equine estrogens (CEE) for 21 days; group II received oral CEE for 21 days and, after 14 days of this treatment, 5 mg/day of medrogestone was added for 7 days; group III did not receive any therapy (controls). Endogenous and copper-induced serum levels of lipid peroxides were determined before and after 21 days of treatment in the two treated groups and in the control group. RESULTS: The serum endogenous levels of lipid peroxides in postmenopausal women did not change after short-term treatment with hormone replacement therapy. Moreover, copper-induced serum levels of lipid peroxides significantly decreased after therapy in both groups I and II. CONCLUSIONS: Our data show that hormone replacement therapy (HRT) inhibits lipid peroxidation and may play a role in preventing cardiovascular diseases.

Cardiovascular Diseases↗
PubMed1999

Sentinel node biopsy and selective lymph node dissection in cutaneous melanoma patients.

Sentinel node biopsy allows an accurate selection of melanoma patients to be submitted to therapeutic dissection. From February 1994 to August 1998, at the National Cancer Institute, S. Pio X Hospital in Milan and Bufalini Hospital in Cesena, 580 sentinel node biopsies were performed in 540 stage I melanoma patients (242 males; 298 females; median age 47). Primary melanoma was located in the trunk in 201 patients, in lower limbs in 242 cases, in upper limbs in 80 cases and in head and neck in 17 patients. Injection of blue dye for sentinel node identification was performed in all cases; 372 patients were submitted to preoperative lymphoscintigraphy and in 272 cases an intraoperatory probe for a radioguided biopsy was utilized. Sentinel node identification rate was 91%. Sentinel node positivity rate was 15%. Frozen sections were examined in 199 cases. Distribution of positive cases according to primary thickness is the following: <1 mm: 1%; 1-1.99 mm: 5%; 2-2.99 mm: 18% and > or =3 mm: 27%. Sentinel node appeared to be the only metastatic node in 77% of patients submitted to dissection. The adoption of preoperative lymphoscintigraphy and the intraoperative use of the gamma probe contributed substantially in S.N. identification. No complications caused by the procedure were reported. Eight patients had a regional node relapse after a negative sentinel node biopsy and were submitted to therapeutic distant dissection. Currently 513 patients are alive with no evidence of disease. Present data confirm the feasibility and safety of sentinel node technique for selection of patients to be submitted to radical node dissection and to eventual adjuvant treatments.

Adolescent↗
PubMed1998

Spectrophotometric imaging of cutaneous pigmented lesions: discriminant analysis, optical properties and histological characteristics.

Reflectance imaging spectroscopy at 17 selected wavelengths in the range 420-1040 nm has been applied as a method to discriminate melanoma from other pigmented cutaneous lesions. Reflectance images are acquired for 18 primary melanomas and 33 benign naevi in 44 patients. From each spectral image, four parameters related to lesion reflectance (mean value of reflectance, variegation, area and roundness of lesion) are derived at the corresponding wavelength. A discriminant function between the two groups of lesions is determined by using a stepwise discriminant analysis, resulting in a test with a sensitivity of 89% and a specificity of 88%. Since analyses are carried out on the same data set used to obtain the discriminant function, our results should be interpreted with caution. Moreover, in an attempt to assign a physical and/or physiological meaning to the lesion image descriptors, some histological features (i.e., lesion thickness, degree and uniformity of pigmentation) have also been analysed, and their correlations with the image descriptors investigated. Neither degree nor uniformity of pigmentation can fully explain the variations observed in the lesion image descriptors. It is hypothesized that the presence of pathologically related biological components such as lymphocytes and highly aggregated cells may play an important role. The actual performance of the spectrophotometric imaging system should be proven in an additional, unselected number of cases before being used as a diagnostic adjunct for physicians in the clinical detection of melanoma.

Diagnosis, Differential↗
PubMed1998

Evaluation of clinical efficacy and tolerability of intravenous high dose thymopentin in advanced melanoma patients.

Thymopentin (TP5) has been recently evaluated as an immunotherapeutic agent for the treatment of cancer. Melanoma is a highly immunogenic malignancy, and in our previous studies the treatment of metastatic melanoma with TP5 showed encouraging results. In the present study, we evaluated the clinical efficacy and tolerability of high dose intravenous TP5 in 16 patients with melanoma which had metastasized to cutaneous and subcutaneous tissue. All patients were given 1 g intravenous TP5 every second day for 7 weeks and were then evaluated; responders were given a subsequent course of 2 g intravenous TP5 every second day for 5 weeks. Six patients showed a partial response after the first course and were given the second course: one patient achieved a complete response, while the other five remained in partial response at the end of the treatment. The mean duration of response was 7.5 months. No drug side effects were observed. Histopathological and immunohistochemical evaluation of regressing metastatic nodules showed the presence of tumour-infiltrating lymphocytes, necrosis, sclerosis, intratumoral vascular proliferation and microthrombosis. Immunophenotyping of lymphoid infiltrates demonstrated the prevalence of CD4+ and CD45RO+ T-lymphocytes in one patient. We conclude that high dose intravenous TP5 three times a week may induce a clinical response in patients with cutaneous and subcutaneous metastases of melanoma without relevant side effects.

Adjuvants, Immunologic↗
PubMed1998

Immunohistochemical analysis of the T-cell receptor beta-chain variable regions expressed by T lymphocytes infiltrating primary human melanoma.

The T-cell receptor beta-chain variable (TCRBV) region repertoire expressed by tumor-infiltrating lymphocytes was characterized by immunohistochemical analysis using a panel of 18 monoclonal antibodies on cryosectioned specimens of 14 primary vertical growth phase (VGP) melanomas with a T-cell infiltrate histopathologically defined as brisk or nonbrisk. T lymphocytes present in the VGP of all patients displayed a restricted T-cell receptor usage, with a pattern of reactivity similar in brisk versus nonbrisk infiltrates. No evidence of restriction was found in the extra-VGP lymphocytic infiltrates, when available, within the same specimen. Furthermore, the repertoire of TCRBV expressed in nodal metastases was similar to that of the corresponding primary melanomas in the two cases tested. The results obtained by this in situ analysis indicate that the TCRBV repertoire in VGP is determined by a preferential migration of T lymphocytes, possibly indicative of an immune response to melanoma-associated antigens.

Adult↗
PubMed1997

G-proteins and beta-adrenergic stimulation of adenylate cyclase activity in the diabetic rat prostate.

BACKGROUND: The consequences of experimental diabetes on membrane lipids, beta-adrenergic stimulation of adenylate cyclase activity, and G-protein levels in the prostate gland are not defined. METHODS: Prostatic membranes from control and streptozotocin (STZ)-diabetic rats were used to study adenylate cyclase stimulation as well as for immunodetection of stimulatory (alpha s) and inhibitory (alpha i) G-protein subunits. Changes in membrane lipid composition were estimated by [1-14C] acetate incorporation into lipid subclasses. RESULTS: The efficacy of isoproterenol on stimulation of adenylate cyclase activity and the levels of alpha s, alpha i1/2, and alpha i3/0 G-protein subunits were drastically reduced in prostatic membranes from STZ-diabetic rats. Insulin treatment of diabetic rats tended to normalize G-protein levels, but it was ineffective on the poor adenylate cyclase response to isoproterenol or forskolin. However, it prevented enzyme desensitization to vasoactive intestinal peptide. The pattern of [1-14C] acetate incorporation into lipid subclasses did not vary with diabetes or insulin treatment. CONCLUSIONS: STZ-induced diabetes results in desensitization for the beta-adrenergic response of adenylate cyclase, as supported by previous data on the low density of beta-adrenergic receptors and the present results on the general decrease of Gs and Gi proteins levels and even of the enzyme itself in the diabetic rat prostate.

Acetates↗
PubMed1997

Active immunization of metastatic melanoma patients with interleukin-2-transduced allogeneic melanoma cells: evaluation of efficacy and tolerability.

From January 1994 to July 1996 we immunized metastatic melanoma patients with HLA-A2-compatible, interleukin-2 (IL-2)-secreting, immunogenic melanoma lines in an attempt to induce a systemic reaction that might also affect distant melanoma lesions. Twelve patients (6 male and 6 female) aged from 28 to 72 years, affected with visceral and/or subcutaneous (s.c.) melanoma metastases, were treated. Two different HLA-A2+ melanoma lines were transduced with the human IL-2 gene (14932/IL-2 and 1B6/IL-2) and used as vaccine. Two groups of 4 patients each were injected s.c. with 5 x 10(7) and 15 x 10(7) irradiated 14932/IL-2 melanoma cells respectively, whereas a third group received 5 x 10(7) cells of the second line (1B6/IL-2). All patients received the vaccine on days 1, 13, 26; if no progression was evident, further immunizations were administered at monthly intervals. All patients were assessable for clinical response after at least three injections of the vaccine. In 4 cases a stabilization of disease lasting from 2 to 6 months was observed: in 2 of them a mixed type of response to treatment was noted with simultaneous evidence of regressing and non-responding lesions in the same patients. No signs of clinical response were found in the remaining patients. Nine patients died of disease between 3 and 24 months after the onset of therapy, whereas 3 were alive 3 months after the end of therapy. The local and systemic side-effects of treatment were mild. These results indicate that vaccination with cells bearing the appropriate antigens and releasing IL-2 locally can produce weak clinical responses, but also indicate that better results may be achieved through modifications of the vaccine, the schedule of immunization and/or a more appropriate selection of patients.

Adult↗
PubMed1997

Ambulatory narrow excision for thin melanoma (< or = 2 mm): results of a prospective study.

Although narrow surgical excision may be sufficient for thin melanoma, questions remain concerning how narrow the excision should be and how it should be related to tumour thickness. To address these issues, a group of 168 consecutive patients with primary invasive melanoma up to 2 mm thick underwent ambulatory surgery with excision margins of 1 cm. 40 (24%) of these patients had lesions thicker than 1 mm. In a median follow-up of 5 years, 11 patients relapsed and 3 developed second malignancies. The crude cumulative incidence of regional and distant metastases were, respectively, 5.6% and 1.5%. No local isolated recurrence was observed, indicating that ambulatory narrow excision is justified for melanoma up to 2 mm thick.

Ambulatory Surgical Procedures↗
PubMed1996

Clinical diagnosis and therapy of cutaneous melanoma in situ.

BACKGROUND: The frequency of in situ melanoma is increasing, and it is often diagnosed fortuitously by histology. METHODS: We retrospectively reviewed 121 melanomas in situ in 113 patients with the aim of identifying the clinical features of, and optimal surgical treatment for this cutaneous malignancy. Treatment was limited surgery with 3 mm margins of excision in 69 cases (57%) and wider margins of excision (more than 3 mm) in 52 cases (43%). The lesions had a median diameter of 1 cm (range, 2-35 mm) and were generally macular (92% of cases) asymmetric (87%), with an irregular border (88%) and nonuniform pigmentation (98%), usually in shades of brown (41%) and black (48%). These features had permitted a clinical diagnosis of melanoma or suspected melanoma in 62% of cases and of doubtful nevus in an additional 18% of cases. RESULTS: At a median follow-up of 4 years, there were six local recurrences (three treated by limited surgery and three by wider excision), all in situ melanomas. CONCLUSIONS: The typical clinical features of melanoma in situ, which are similar to those of early invasive melanoma, are usually sufficiently distinctive to suggest the clinical diagnosis of melanoma or suspected melanoma. Except for large size and superficially extended lesions (larger than 2 cm), adequate treatment is excision with 3 mm margins, although larger lesions (larger then 2 cm) may have an appreciable incidence of local recurrence.

Aged↗
PubMed1996

The invisible colours of melanoma. A telespectrophotometric diagnostic approach on pigmented skin lesions.

Reflectance images of 43 pigmented lesions of the skin (18 melanomas, 17 common melanocytic naevi and eight dysplastic naevi) were acquired by a telespectrophotometric system and were analysed in the spectral range from 420 to 1040 nm, to discriminate melanoma from benign melanocytic entities. Different evaluations were carried out considering the whole spectrum, the visible and the near infra-red. A total of 33 (76.7%) lesions were correctly diagnosed by the telespectrophotometric system, compared with 35 (81.4%) correct clinical diagnoses. Reflectance in the infra-red band appears diagnostically relevant. A larger study is needed to prove the validity of this diagnostic method.

Diagnosis, Differential↗
PubMed1996

alpha-Tocopherol and beta-carotene serum levels in post-menopausal women treated with transdermal estradiol and oral medroxyprogesterone acetate.

Estrogens exert a protective effect against atherosclerosis. It is well known that hormone replacement therapy (HRT) can effectively decrease LDL-cholesterol and increase HDL-cholesterol and Apo-Al serum levels. Some recent studies have suggested that estrogens alone or in association with progestins may exert an antioxidant effect on lipids. Besides sex steroids, also vitamins exert an antioxidant effect on LDL and may preserve the endogenous antioxidants of LDL. The aim of our study was to evaluate whether HRT can improve alpha-tocopherol and beta-carotene serum levels in post-menopausal women. Fifteen postmenopausal women with climacteric symptoms were treated with 50 micrograms/24 h estradiol transdermally applied twice a week for 21 days. A daily dose of 10 mg oral medroxyprogesterone acetate was added for 12 days in each treatment cycle. This therapy lasted 6 months. A significant reduction was found in total cholesterol and LDL-cholesterol after treatment. Besides, our study has shown that alpha-toc/LDL and beta-car/LDL ratios significatively increased after treatment, while alpha-tocopherol and beta-carotene serum levels did not change significantly after therapy. These preliminary findings suggest that HRT can preserve the content of alpha-tocopherol and beta-carotene in LDL particles and keep the LDL in a reduced antioxidant state.

Administration, Cutaneous↗