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Biomedical subjects

P Ferrari

Publications and source records attributed to P Ferrari.

At least 181 records · Page 10Linked to original sources
PubMed1996

Cell-mediated immunity in breast cancer patients.

In clinical practice, reports have been made on immunosuppression after surgical excision of primary tumor or at relapse. However, the relationship between undefined or overt metastases and the host immune system has not been sufficiently examined over a prolonged period. These aspects were investigated in 160 breast cancer patients followed up post-operatively with serial controls over a long period. One hundred and thirty-four cases (91 node negative, (N-), 43 node positive (N+)) were disease-free and 26 relapsed. In all patients, serum T cell populations, serum B lymphocytes and skin reaction of delayed hypersensitivity (SRDH) were serially determined for 39 +/- 12 months (m +/- SD). The reference values for these parameters were assessed as follows: T populations were evaluated in 24 healthy donors and SRDH in 95 healthy females. In non-relapsed patients, constant CD8+ T cell decrease and T4/T8 ratio increase were observed; the T4/T8 ratio was significantly higher (ranging from P < 0.05 - P < 0.001) than in the control group. The mean values of NK cells and B lymphocytes, the former parameter being highly significant (P < 0.001), were higher than in controls. In the 26 metastatic patients, the T4/T8 ratio from 20 months before to 30 months after the first sign of relapse decreased from 3.2 to about 1 (r = -0.256, P < 0.05) and from 30 to 92 months after relapse progressively increased to 2. Similarly, in the former subinterval a progressive decrease in the number of positive antigens and score was found (from 2.4 to 0 and from 10 to zero respectively). A significant inverse correlation between these two parameters and observation time occurred (P < 0.01 and P < 0.001 respectively). From 30 to 86 months after relapse, a progressive increase in the number of positive antigens and scores up to 2 and 12 were observed. A significant direct correlation (P < 0.05) was noted. In conclusion, these data indicate significant changes in T populations during the disease-free interval in breast cancer patients. The decrease in circulating CD8+ T cells is compatible with the hypothesis of CD8+ T cell localization at the site of the micrometastases. The increase in circulating B lymphocytes and NK cells suggests activation of aspecific humoral immunity and NK function. In addition, they show that progressive deficiency in cell-mediated immunity appears many months before and that recovery continues for a long time after overt metastatic disease.

Breast Neoplasms↗
PubMed1996

Immunological and side effects of low sc recombinant interleukin-2 dose in addition to conventional treatment in relapsed breast and colorectal cancer patients.

Thirteen relapsed cancer patients, four of them operated for colorectal and the nine remaining for breast cancer, were cyclically given low subcutaneous (sc) recombinant interleukin-2 (rIL-2) doses in addition to chemo- or hormone therapy. Cycle intervals were 2 or 6 weeks in length, and the number of cycles ranged from one to 14 and from one to six respectively. Tolerance assessed by clinical and laboratory data, eosinophils, lymphocytes (total number), T subpopulations, B lymphocytes and NK cells were the evaluated parameters. One (7.6%) of the 13 studied patients interrupted the first low dose sc rIL-2 cycle due to a hypersensitive reaction. This case showed relapse from breast cancer. During further cycles, three patients (25%), one operated on for colorectal and two others for breast cancer of the 12 remaining cases who completed all rIL-2 cycles showed an increase in glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), gamma-gt, and creatininemia without any clinical symptoms. A slight influenza-like syndrome and 10-20 mmHg decrease in blood pressure sporadically occurred in all patients under rIL-2 therapy. In both cancer types, a significant (P < 0.05 - P < 0.001) increase in lymphocytes, eosinophils. T4 and T3 subpopulations but not in T8 subpopulations and NK cells occurred at the end of the rIL-2 cycles. In 11 of the 13 patients responsive to conventional therapy, a highly significant increase (P < 0.001) in all parameters apart from B lymphocytes and T4/T8 ratio was observed, while in three cases which were no longer responsive and in another case which had never been responsive to conventional therapy, a slightly significant increase in eosinophils only occurred (P < 0.05). Three colorectal cancer patients showed a partial response and the last a complete response to conventional therapy. In these four patients, time to progression during rIL-2 cycles ranged from 2.5-5 months and the duration of response ranged from 8-19 months. In seven of the eight breast cancer patients who completed all rIL-2 cycles, the response ranged from 3-51+ months and in the last case, which was not responsive to conventional therapy, the disease progressed in spite of the addition of rIL-2. These data suggest that: a) rIL-2 is likely to constitute a well-tolerated and suitable home therapy even when cyclically given for a prolonged period; b) following rIL-2 administration, eosinophils and lymphocytes increase in addition to the T subpopulations.

Adult↗
PubMed1996

Substrate and inhibitor specificity of the cloned human 11 beta-hydroxysteroid dehydrogenase type 2 isoform.

The 11 beta-hydroxysteroid dehydrogenase type 2 (11betaHSD2) enzyme is thought to confer specificity on the mineralocorticoid receptor by inactivating glucocorticoids in mineralocorticoid target organs. The cloned 11 beta HSD2 displayed Michaelis constant values for corticosterone and cortisol of 5.1 and 61 nM, respectively. Linearity in the dose-response curve ranged between 1 and 200 nM for corticosterone and 25 and 2,000 nM for cortisol, with no evidence for complex kinetics. Inhibition of cortisol oxidation by other steroids was purely competitive in nature. Inhibition of 11 beta HSD2 activity by the end product or aldosterone occurred only at supraphysiological levels, whereas corticosterone and deoxycorticosterone displayed significant inhibition at physiological concentrations and progesterone at concentrations that occur during pregnancy. In intact transfected CHOP cells, dexamethasone was converted to 11-dehydrodexamethasone by 11 beta HSD2 but not type 1 11 beta-hydroxysteroid dehydrogenase, an aspect that may be useful in evaluating 11 beta HSD activity in intact cells.

11-beta-Hydroxysteroid Dehydrogenases↗
PubMed1996

Combination treatment versus LHRH alone in advanced prostatic cancer.

Androgen deprivation based on hormone manipulation is the treatment of choice in advanced prostatic cancer. The unequivocal role of adrenal androgens in the growth of prostatic cancer after medical or surgical castration requires a new logical approach (complete androgen blockade) in the treatment of advanced prostate cancer. One hundred and fifty patients with biopsy-proven advanced prostatic cancer were randomized into two groups. One group (74 patients) received leuprolide + flutamide (complete androgen blockade); the second group (76 patients) received only leuprolide and, during the first 3 weeks of treatment, cyproterone acetate (150 mg/day) to prevent flare-up phenomena. The aim of the study was to evaluate the differences between the two groups on overall survival and time to progression (log-rank test). One hundred and twenty-five patients were evaluable, 62 in the leuprolide-only group and 63 in the leuprolide + flutamide group. Median duration of follow-up was 102 weeks. No statistical difference between the two groups was observed in overall survival, in time to disease progression, and in time to treatment failure. In the combination (leuprolide + flutamide) treatment group, a positive trend for overall survival and in time to progression was observed in a subgroup of patients with good performance status and no bone metastases. We observed mild gastrointestinal toxicity (diarrhea, nausea) in the group treated with leuprolide + flutamide. The aim of this study was to compare the effectiveness of total androgen withdrawal with medical testicular suppression in advanced prostatic cancer. No significant statistical difference was observed between the two groups in overall survival and in time to progression, but probably too few patients were enrolled in each treatment arm to give a statistical interpretation of our results. We conclude that there is a positive trend in the combination treatment arm in patients with good prognostic factors.

Age Distribution↗
PubMed1996

Renal Na,K-ATPase in genetic hypertension.

Milan hypertensive rats (MHS) develop hypertension because of a primary renal alteration. Both apical and basolateral sodium transport are faster in membrane vesicles derived from renal tubules of MHS than in those of Milan normotensive control rats (MNS). These findings suggest that the increased renal sodium retention and concomitant development of hypertension in MHS may be linked to an altered transepithelial sodium transport. Since this transport is mainly under the control of the Na-K pump, we investigated whether an alteration of the enzymatic activity and/or protein expression of the renal Na,K-ATPase is detectable in prehypertensive MHS. We measured the Na,K-ATPase activity, Rb+ occlusion, turnover number, alpha 1- and beta 1-subunit protein abundance, and alpha 1 and beta 1 mRNA levels in microsomes from renal outer medulla of young (prehypertensive) and adult (hypertensive) MHS and in age-matched MNS. In both young and adult MHS, the Na,K-ATPase activity was significantly higher because of an enhanced number of active pump sites, as determined by Rb+ occlusion maximal binding. The higher number of pump sites was associated with a significant pretranslational increase of alpha 1 and beta 1 mRNA levels that preceded the development of hypertension in MHS. Since a molecular alteration of the cytoskeletal protein adducin is genetically associated with hypertension in MHS and is able to affect the actin-cytoskeleton and Na-K pump activity in transfected renal cells, we propose that the in vivo upregulation of Na-K pump in MHS is primary and linked to a genetic alteration of adducin.

Aging↗
PubMed1996

Acute cyclosporine-induced nephrotoxicity in renal transplant recipients: the role of the transplanted kidney.

Cyclosporine A causes an acute reduction in GFR. The interindividual variable reduction in GFR is most likely the result of arteriolar vasoconstriction. Vasoconstriction is attributable either to a local effect of cyclosporine on renal blood vessels (intrinsic mechanism) or to a systemic effect of cyclosporine on circulating and/or neuronal factors (extrinsic mechanism). The aim of the investigation presented here was to establish whether intrinsic or extrinsic mechanisms account for the interindividual differences in the susceptibility to acute cyclosporine-induced nephrotoxicity. For that purpose, this study took advantage of the clinical transplant situation in which two (intrinsically identical) kidneys from a cadaveric donor are transplanted into two (extrinsically) different subjects. The preexisting regular daily cyclosporine doses were raised by 25% for 2 wk and by 50% for another 2 wk in 16 patients with stable renal graft function, representing eight pairs of patients, each of whom had received kidneys from the same donor. In these patients, a mean (+/- SD) maximum cyclosporine-induced increase in serum creatinine concentration of 13 +/- 11% (P < 0.001) and in serum BUN of 27 +/- 33% (P < 0.01), together with a decline in the fractional uric acid excretion of 51 +/- 89% (P < 0.02) were observed. The percentage change in serum creatinine concentrations after increased dosing of cyclosporine paralleled within the subjects receiving their kidneys from the same donor, i.e., when one recipient experienced a large percentage of change after increases of cyclosporine dosing, the corresponding recipient of a kidney from the same donor had a change of the same magnitude. Seven of eight pairs showed a consistent response with respect to a clinically significant increase in serum creatinine concentration of > 15%, with a consistent response purely by chance being < 5%. Thus, the transplanted kidney itself rather than the recipient determines the susceptibility to acute cyclosporine-induced nephrotoxicity.

Acute Kidney Injury↗
PubMed1996

Reduced plasma cyclic GMP but normal renal responses to atrial natriuretic factor in pre-hypertension.

The amount of, and response of the kidneys to, endogenous natriuretic factor(s) could be important in the pathogenesis of essential hypertension. Searching for possible disturbance(s) related to atrial natriuretic factor (ANF) and its second messenger, cyclic guanosine monophosphate (c-GMP), we assessed plasma immunoreactive (ir) ANF and c-GMP, effective renal plasma flow (ERPF), glomerular filtration rate (GFR), urinary c-GMP, absolute and fractional (FE) excretions of sodium (Na) and chloride (Cl) before and during infusions of low ANF doses or vehicle (V) in 7 normotensive sons of essential hypertensive parents (SEH) compared with 7 sons of normotensive parents (SN). Each subject was infused at 2-week intervals in a single-blind randomized sequence with 4 different solutions: V only or ANF 0.004, 0.008 and 0.016 microgram/kg/min, infused over 90 min. Plasma irANF was lower in SEH than in SN (p < 0.001) during vehicle infusion. Basal plasma c-GMP levels were, on all 4 different study days lower (p < 0.05 to < 0.01) in SEH in SN. Response of plasma c-GMP to infused ANF was also slightly decreased in SEH (p < 0.05 to < 0.01). BP, ERPF and GFR did not differ between SEH and SN and were unchanged during the 4 infusions. Urinary c-GMP excretion, FENa and FECl increased dose-dependently during ANF (p < 0.05 to < 0.0001) but not V infusions. These findings indicate that at the stage of pre-hypertension a disturbance in the ANF-c-GMP regulatory pathway may occur, which is expressed primarily at the circulatory rather than the renal excretory level.

Atrial Natriuretic Factor↗
PubMed1996

Synthesis and antibacterial activity of derivatives of the glycopeptide antibiotic A-40926 and its aglycone.

Starting from the antibiotic A-40926 and the aglycone of A-40926 a series of compounds were prepared by modifying the free functionalities. Their antimicrobial activity was determined, particularly against Neisseria gonorrhoeae, against which A-40926, unlike other natural glycopeptides, is active. Improved in vivo activity was displayed by the monomethyl ester of A-40926 esterified at the carboxyl group of the N-acylamino-glucuronyl moiety.

Animals↗
PubMed1996

Synthesis and biological evaluation of new fragments from kirromycin antibiotic.

New N-acyl derivatives of 1-N-desmethyl goldinamine were obtained from degradation of kirromycin. Periodate-oxidation of these derivatives provided new aldehydic fragments that were further elaborated. Both N-phenyl ureido and N-phthalimido derivatives of 1-N-desmethyl goldinamine are able to inhibit bacterial protein synthesis in cell-free assay and are active against whole microorganisms, although with lower potency than kirromycin. The derivatives from the aldehydic fragments are totally inactive.

Anti-Bacterial Agents↗
PubMed1996

Antibiotics A21459 A and B, new inhibitors of bacterial protein synthesis. II. Structure elucidation.

The structures of the antibiotics, active against a few Gram-negative bacteria and Clostridium difficile, were determined on the basis of physicochemical analyses on the intact molecules and on the acid hydrolysate of A21459 A. FAB-MS and 1H and 13C NMR investigations identified the amino acid units and determined their sequence. Antibiotics A21459 A and B are homodetic cyclic peptides constituted by eight amino acid units. They are glycine, methoxytryptophan, tryptophan, cysteine, alanine, sarcosine, dehydroalanine, and alpha-aminobutyric acid for A21459 A (alanine for A21459 B). Cysteine and alanine condensed to form a thiazole moiety, according to the biosynthesis of thiazole containing antibiotics.

Amino Acid Sequence↗
PubMed1996

Inhibitors of myo-inositol monophosphatase, ATCC 20928 factors A and C. Isolation, physico-chemical characterization and biological properties.

During the course of a screening program for inhibitors of myo-inositol monophosphatase we fermented the strain ATCC 20928, a known producer of L-671,776. We now show that this strain produces a complex of at least three sesquiterpenic compounds, L-671,776 (termed factor B) and two structurally related substances, termed factors A and C. Both factors A and C, like L-671,776, exhibited inhibitory activity against myo-inositol monophosphatase. Six other fungi producing the above mentioned compounds were also isolated and taxonomically characterized.

Benzofurans↗
PubMed1996

Isolation and structure determination of a novel complex of the teicoplanin family.

A new teicoplanin-like antibiotic was discovered when using Actinoplanes teichomyceticus strain 3/W, the fermentation medium containing Alburex, and the fermentation time 275 hours. The new product was separated from teicoplanin complex by polyamide resin chromatography and purified by Amberlite XAD-7 and affinity resin chromatographies. The structure was established on the basis of the physico-chemical characteristics of the complex and of its aglycone. The new structure is that of teicoplanin with a carbonyl group substituting for the CHNH2 group of amino acid 1. We hypothesize that the novel complex is a transformation product of teicoplanin due to a simple transamination reaction, as supported by its structure and by the concomitant decrease in teicoplanin concentration during its production.

Actinomycetales↗
PubMed1996

Synthesis and antimicrobial activities of 4-purpuromycin derivatives.

Purpuromycin (1) is a natural antibiotic with a broad spectrum of activity encompassing bacteria, fungi and protozoa. A new series of derivatives of 1 was prepared by the modification or replacement of the C-4 hydroxyl group. The physico-chemical characteristics and the in vitro antimicrobial activity of these new semisynthetic purpuromycin derivatives are reported. Attachment of a variety of bulky groups to the C-4 hydroxyl group as well as acylation or mesylation of 1 gave derivatives with significantly reduced antifungal activity, while the antimicrobial activity of these derivatives against Gram-positive and Gram-negative bacteria was only slightly decreased. All compounds were inactive against Escherichia coli. The C-4 epimers showed different in vitro activity as compared with those having the natural configuration, particularly against fungi.

Anti-Bacterial Agents↗