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C Floris

Publications and source records attributed to C Floris.

At least 19 recordsLinked to original sources
PubMed2001

Antimicrobial evaluation of coumarins and flavonoids from the stems of Daphne gnidium L.

The antimicrobial activity of stems methanol extract from Daphne gnidium L. collected from Sardinia (Italy) was evaluated against 6 strains of standard and clinical isolated gram (+/-) bacteria. The antimicrobial effect on two strains of fungi was also tested. The extract in toto exhibited antibacterial activity against Bacillus lentus and Escherichia coli, but was inactive against fungi. Four coumarins (daphnetin, daphnin, acetylumbelliferone, daphnoretin) and seven flavonoids (luteolin, orientin, isoorientin, apigenin-7-O-glucoside, genkwanin, 5-O-beta-D-primeverosyl genkwanine, 2,5,7,4'-tetrahydroxyisoflavanol) present in the plant extract were also investigated against the same strains of bacteria and fungi assayed for the crude extract. The most active compounds were daphnetin, genkwanin, and 2,5,7,4'-tetrahydroxyisoflavanol.

Anti-Bacterial Agents↗
PubMed2000

Definition of the role of chromosome 9p21 in sporadic melanoma through genetic analysis of primary tumours and their metastases. The Melanoma Cooperative Group.

Malignant melanoma (MM) is thought to arise by sequential accumulation of genetic alterations in normal melanocytes. Previous cytogenetic and molecular studies indicated the 9p21 as the chromosomal region involved in MM pathogenesis. In addition to the CDKN genes (p16/CDKN2A, p15/CDKN2B and p19(ARF), frequently inactivated in familial MM), widely reported data suggested the presence within this region of other melanoma susceptibility gene(s). To clearly assess the role of the 9p21 region in sporadic melanoma, we evaluated the presence of microsatellite instability (MSI) and loss of heterozygosity (LOH) in primary tumours as well as in synchronous or asynchronous metastases obtained from the same MM patients, using 9 polymorphic markers from a 17-cM region at 9p21. LOH and MSI were found in 27 (41%) and 11 (17%), respectively, out of 66 primary tumours analysed. In corresponding 58 metastases, MSI was found at higher rate (22; 38%), whereas a quite identical pattern of allelic deletions with 27 (47%) LOH+ cases were observed. Although the CDKN locus was mostly affected by LOH, an additional region of common allelic deletion corresponding to marker D9S171 was also identified. No significant statistical correlation between any 9p21 genetic alteration (LOH, MSI or both) and clinicopathological parameters was observed.

Adolescent↗
PubMed1999

Reversal by flunarizine of the decrease in hippocampal acetylcholine release in pentylenetetrazole-kindled rats.

The aim of our study was to evaluate the effect of the non-selective calcium antagonist flunarizine on hippocampal acetylcholine (ACh) release with the microdialysis technique in freely moving rats after long-term concomitant administration of pentylenetetrazole (PTZ) in comparison with rats treated long-term with PTZ (kindled animals). The basal extracellular concentration of ACh in the hippocampus of rats treated with PTZ alone was significantly reduced relative to that of vehicle-treated rats (2.04+/-0.2 vs 3.94+/-0.3 pmol per 20-min sample; P < 0.01). Administration of flunarizine (7.5 mg/kg i.p.) before each PTZ injection prevented this decrease in basal ACh output (3.75+/-0.4 pmol per 20-min sample). On the contrary, the expression of PTZ-induced kindling was not prevented by administration of flunarizine. The specific antagonistic effect of flunarizine on the kindling-induced decrease in hippocampal ACh release is shared by the selective antagonist of the L-type calcium channel, nifedipine, but not by the dopamine D2 antagonist, (-)-sulpiride, suggesting that the decrease in Ca2+ overload by a blockade of the L-type calcium channel may be responsible for the protective action on cholinergic neurons exerted by flunarizine. These data also suggest a potential therapeutic role for flunarizine in counteracting impairment of hippocampal cholinergic activity.

Acetylcholine↗
PubMed1999

Molecular and neurochemical evaluation of the effects of etizolam on GABAA receptors under normal and stress conditions.

The thienobenzodiazepine derivative etizolam (CAS 40054-69-1, 6-(o-chlorophenyl)-8-ethyl-1-methyl-4H-s-triazolo-(3,4-c)thienol(1 ,4) diazepine) is a potent anxiolytic with a pharmacological profile similar to that of classical benzodiazepines. In order to rationalize the therapeutic use of etizolam, its pharmacodynamics properties on GABAA receptors were investigated by a comparative study with other ligands on human recombinant GABAA as well as rat brain native receptors. Etizolam inhibited in a concentration-dependent manner [3H]flunitrazepam (CAS 1622-62-4) binding to rat cortical membranes, with an affinity of 4.5 nmol/l greater than that of alprazolam (CAS 28981-97-7) (7.9 nmol/l). Ethizolam enhanced GABA-induced Cl- currents in oocytes expressing human cloned GABAA receptors. With alpha 1 beta 2 gamma 2S subunit combination, etizolam produced a 73% increase in GABA-induced currents with an EC50 of 92 nmol/l. At the same receptor type, alprazolam showed a higher degree of potentiation and potency (98%, EC50 56 nmol/l). At alpha 2 beta 2 gamma 2S or alpha 3 beta 2 gamma 2S subunit constructs, the effects of etizolam were similar to those of alprazolam. Flumazenil (CAS 78755-81-4) completely blocked both etizolam and alprazolam effects on GABA-induced currents. Etizolam, administered i.p., was uneffective in changing ex vivo t-[35S]butylbicyclophosphorothionate ([35S]-TBPS) binding to rat cerebral cortex, whereas alprazolam and abecarnil (CAS 111841-85-1) significantly reduced this parameter. However, etizolam similarly to abecarnil and alprazolam, antagonized isoniazid-induced increase (61%) in [35S]-TBPS binding to rat cortical membranes. Further, etizolam inhibited in a dose-dependent manner basal acetylcholine release from both hippocampus and prefrontal cortex, and reversed foot-shock-induced increase of basal acetylcholine release to a control level. Altogether, these results suggest that etizolam may have a reduced intrinsic activity, at least at specific subpopulations of GABAA receptors. This property, together with the pharmacokinetic indication of a short-acting drug, may characterize etizolam as a ligand endowed with less side-effects typical of full agonits such as diazepam (CAS 439-14-5) and alprazolam. Finally, given its marked efficacy under conditions of GABAergic deficit, etizolam may represent a possible drug of choice with reduced liability to produce tolerance and dependence after long-term treatment of anxiety and stress syndromes.

Acetylcholine↗
PubMed1989

Intralymphatic infusion of interferon in patients with lymph nodal metastases from melanoma of the lower limbs.

In five patients with regional lymph nodal metastases from malignant melanoma of the lower limbs, intralymphatic infusion of interferon caused a complete remission in one patient and a partial remission in two others. The remaining two patients, in whom the massive neoplastic infiltration had obstructed the inflow of the drug in the tumoural seat, were unresponsive. Since the efficacy of interferon seems to be dose-dependent, intralymphatic infusion causes the accumulation of massive quantities of the drug in the tumoural seat, thus favouring its antiproliferative action.

Adult↗
PubMed1988

Role of interleukin-2 (IL-2) in cancer-related immune deficiency: in vitro response to IL-2, production of IL-2, and IL-2 receptor expression in patients with advanced cancer.

The aims of the investigation were 1) to determine if there are defects in interleukin-2 (IL-2) regulation on either phytohemagglutinin (PHA)-activated or non-PHA-activated peripheral blood mononuclear cells (PBMC) in cancer patients to ascertain the role of IL-2 in this disease; 2) to carry out preliminary experiments for a direct quantitative evaluation of endogenous IL-2 production by PBMC cultures; and 3) to evaluate the IL-2 receptor expression by PBMC of cancer patients. An assessment of lymphocyte subsets was also performed with monoclonal antibodies in a selected group of patients. A total of 170 patients entered the study. Cancer sites were larynx (48), breast (44), lung (30), colorectal(23), and gynecologic (25). Staging showed in the former three cancer sites predominantly localized or only locally advanced disease and in the latter two sites disseminated disease. PBMC cultures were performed with microtiter plate technique and 3H-thymidine uptake evaluation using polyclonal mitogens, IL-2, and a monoclonal antibody against IL-2 receptor. Our results provided evidence that the cancer patients exhibit a T-cell functional immunodepression, which, to some extent, progresses during tumor growth so that the localized disease shows a low-grade defect and advanced disease a high-grade defect. Our data also clearly suggest that IL-2 deficiency is the primary factor involved in this functional immune impairment. We found no significant defect in the IL-2 receptor expression by PBMC of cancer patients. Our data also seem to support the in vivo therapeutic administration of IL-2 and lymphokine-activated killer cells to cancer patients.

Antibodies, Monoclonal↗
PubMed1987

Sequential treatment with interferon and chemotherapy of metastatic malignant melanoma. Total remission of cutaneous and visceral metastasis, but not of cerebral metastasis.

A woman 35 years of age suffering from cutaneous and visceral metastatic melanoma was treated with recombinant Interferon alpha 2b (rIFN alpha 2b) subcutaneously 3 X 10(6) U/m2 3 times a week for 3 months with no apparent effect on the course of the illness. Two months after IFN therapy the patient developed cerebral metastasis. A cycle of carmustine, 100 mg/day for 3 days, was given, and complete disappearance of the cutaneous and visceral, but not of the cerebral manifestations was observed. Two consolidation cycles based on vincristine, dacarbazine and lomustine were then administered. The patient died 26 months after beginning treatment with IFN and 18 months after chemotherapy for the cerebral metastasis. No trace of tumor at the cutaneous or visceral level was found at autopsy.

Adult↗
PubMed1987

Interleukin 2 (IL 2) relationships with the cancer-related immunodeficiency: in vitro response to exogenous IL 2 by PHA-activated and non PHA-activated peripheral blood mononuclear cells from cancer patients.

The aims of the investigation were: 1) to determine if there are defects in interleukin 2 (IL 2) regulation either on phytohemagluttinin (PHA)-activated or non PHA-activated peripheral blood mononuclear cells (PBMC) in cancer patients, in order to ascertain the role of IL 2 in this disease, and 2) to carry out preliminary experiments for a direct quantitative evaluation of endogenous IL 2 production by PBMC cultures of cancer patients. An assessment of lymphocytes subsets was also performed with monoclonal antibodies in a selected group of patients. A total of 159 patients entered the study. Cancer sites were: larynx, 49; breast, 42; lung (NSC), 25; colorectal, 18; and gynecologic, 25. In the former 3 cancer sites, staging showed localized or only locally advanced disease and in the later 2 sites it showed disseminated disease. Our results provided evidence that the cancer patients exhibit a T cell functional immunodepression, which progresses during tumor growth, so that the localized disease shows a low-grade defect and advanced disease shows a high-grade defect. Our data also clearly suggested that the factor involved with a primary role in this functional immune impairment is the IL 2 deficiency. In our study we have not found a substantial difference of activity between recombinant and nonrecombinant IL 2, although the comparison of the relative activities of the two types of IL 2 is not easy to make, since they are expressed in different ways; however the recombinant one appeared to be slightly more active, probably for the higher purity. Our data also seem to support the perspective of the in vivo therapeutic administration of IL 2 in cancer patients.

Breast Neoplasms↗
PubMed1986

Peripheral blood lymphocyte response to exogenous interleukin 2 by PHA-prestimulated and non-PHA-prestimulated cells in patients with cancer.

The study aims were to assess the response of peripheral blood lymphocytes (PBL) of cancer patients to exogenous Interleukin 2 (IL 2) either by PHA-prestimulated or non PHA-prestimulated PBL, and to carry out preliminary experiments for a direct quantitative evaluation of endogenous IL 2 production by PBL cultures of cancer patients in order to define the actual role of IL 2 in the disease. Analysis of PBL subsets was also carried out with monoclonal antibodies in a selected group of patients. A total of 134 patients entered the study. Cancer sites were: larynx 32, breast 36, lung (NSC) 24, colorectal 17 and gynecologic 25. In the former 3 cancer sites staging showed localized or only locally advanced disease, and in the last 2 sites disseminated disease. Our results provided evidence that cancer patients exhibit a T-cell functional immunodepression, which progresses during tumor growth, so that the localized disease shows a low-grade defect, and advanced disease a high-grade defect. Our data also clearly suggested that the factor involved with a primary role in this functional immune impairment is the IL 2 deficiency. A perspective may be drawn on the therapeutic administration in vivo of IL 2 and IL 2-activated lymphokine-activated killer cells in controlled clinical trials of selected groups of cancer patients.

Cells, Cultured↗
PubMed1977

Variation of glutamate decarboxylase activity and gamma-amino butyric acid content of wheat embryos during ripening of seeds.

GAD activity and gamma-ABA content of wheat embryos at 7 ripening stages were verified with the aim of studying the metabolic activity of embryo during dehydration and quiescence of caryopsis. Data showed that in the early stage of ripening GAD activity is very low, increases rapidly at dough-stage, remaining constant up to waxy-stage, and decreases in the last fully-ripe embryos. gamma-ABA content appears to be roughly parallel to the variations of GAD activity.

Aminobutyrates↗
PubMed1975

[Electrophoretic mobility of peripheral lymphocytes and Hodgkin's erythrocytes. Correlation with some clinical, hematological and immunological parameters of the disease].

In 32 patients with Hodgkin's disease the electrophoretic mobility of peripheral blood lymphocytes and, at the same time, some clinical, hematological, and immunological parameters of the disease were determined. The mean mobility of lymphocytes was normal; nevertheless, the lymphocytic mobility of 8/32 patients was significantly decreased. No correlation with clinical, hematological, and immunological parameters of the disease was detected. However, the functional deficiency of hodgkinian T lymphocytes seems to play a role in their abnormal electrophoretic behaviour. In 9 out of these 32 patients the electrophoretic mobility of peripheral erythrocytes was also determined. The average mobility was significantly (P less than 0.05) decreased. No correlation with clinical, hematological, and immunological parameters nor with electrophoretic mobility of lymphocytes was detected.

Antibodies, Neoplasm↗