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Biomedical subjects

B Barbieri

Publications and source records attributed to B Barbieri.

At least 19 recordsLinked to original sources
PubMed2004

Endograft treatment in ruptured abdominal aortic aneurysms using the Talent AUI stentgraft system. Design of a feasibility study.

OBJECTIVES: To study the outcome of patients with ruptured AAA treated by EVAR using the Talent AUI stentgraft system. DESIGN: A multicenter prospective consecutive patient cohort of 100 patients. MATERIALS: Consecutive patients with ruptured AAA will be screened for treatment by EVAR. All patients screened, including those excluded from EVAR, will be clustered and called the study group. The study group will be compared with a historical group of patients with ruptured AAA derived from literature. The New ERA study started February 2003. OUTCOME: Main outcome events are applicability rate and operative mortality rate of the study group. CONCLUSION: The study rationale and design are reported here.

Aneurysm, Ruptured↗
PubMed2001

Signaling system in Porphyromonas gingivalis based on a LuxS protein.

The luxS gene of quorum-sensing Vibrio harveyi is required for type 2 autoinducer production. We identified a Porphyromonas gingivalis open reading frame encoding a predicted peptide of 161 aa that shares 29% identity with the amino acid sequence of the LuxS protein of V. harveyi. Conditioned medium from a late-log-phase P. gingivalis culture induced the luciferase operon of V. harveyi, but that from a luxS insertional mutant did not. In P. gingivalis, the expression of luxS mRNA was environmentally controlled and varied according to the cell density and the osmolarity of the culture medium. In addition, differential display PCR showed that the inactivation of P. gingivalis luxS resulted in up-regulation of a hemin acquisition protein and an arginine-specific protease and reduced expression of a hemin-regulated protein, a TonB homologue, and an excinuclease. The data suggest that the luxS gene in P. gingivalis may function to control the expression of genes involved in the acquisition of hemin.

Amino Acid Sequence↗
PubMed2001

[Ovarian function after total simple hysterectomy].

BACKGROUND: The aim of this prospective study is to evaluate the ovarian function and its duration after total simple hysterectomy. METHODS: This research was carried out on thirty regularly menstruating patients who underwent simple hysterectomy. Ovarian function has been evaluated by measuring FSH, E2, PP at 6 and 24 months from hysterectomy or from the first observation at the beginning of the study. RESULTS: None of the patients showed ovarian failure at 6 months. Nine patients (average age: 48,8 years) showed ovarian failure at 24 months. CONCLUSIONS: The conclusion is drawn that the cessation of ovarian activity is not influenced by hysterectomy: it rather depends on the age of the patient.

Adult↗
PubMed1999

p-Aminobenzoic acid and its metabolite p-acetamidobenzoic acid inhibit agonist-induced aggregation and arachidonic acid-induced [Ca2+]i transients in human platelets.

We have previously found that the naturally occurring amine p-aminobenzoic acid (PABA) inhibits the thrombin-induced thromboxane B2 production in human platelets. In this report we show that PABA and its acetylated metabolite p-acetamidobenzoic acid (PACBA) inhibit platelet aggregation induced by agonists such as adenosine diphosphate (ADP) and arachidonic acid (AA). Both substances were equipotent to acetylsalicylic acid regarding inhibition of ADP-induced aggregation and approximately 50% as potent as acetylsalicylic acid regarding arachidonic acid-induced aggregation. Although not significantly inhibiting collagen aggregation, PABA and PACBA reduced the concomitant adenosine triphosphate (ATP) secretion by approximately 30 and 20%, respectively. The antiaggregatory effect does not seem to be mediated through cyclic adenosine monophosphate (cAMP) increase because in our experiments PABA and PACBA did not significantly affect cAMP levels. However, we have found that PABA and PACBA inhibit the intracellular aequorin indicated Ca2+ transient upon arachidonic acid stimulation. Our results describe a hitherto unknown effect of PABA and PACBA on platelet aggregation.

4-Aminobenzoic Acid↗
PubMed1999

Coenzyme Q10 administration increases antibody titer in hepatitis B vaccinated volunteers--a single blind placebo-controlled and randomized clinical study.

Persons involved in the study, 21 per treatment arm, were consuming ubiquinone (Q10), 90 mg/day, 180 mg/day or placebo, for two weeks prior to hepatitis B vaccination. After 30 days this vaccination was repeated. Q10 was given as soft gelatin capsules containing 30 mg each. The consumption was continued throughout the study conducted for 90 days. Clinical observations and laboratory tests were performed throughout the study and no adverse effects were observed in any of the groups. Already after 30 days the two groups receiving Q10 showed a slightly titer of antibodies to hepatitis B surface antigen then the placebo group. This difference escalated and the immunopotentiating effect of Q10 was even more clear-cut in the residual part of the study. In addition, a dose response did also seem to be present when comparing the 90 mg group with the 180 mg group. Statistics revealed that Q10 in the dose 180 mg/day is able to increase antibody response in vivo in humans vaccinated against hepatitis B with up to 57% (p = 0.011).

Analysis of Variance↗
PubMed1998

Lower arachidonic acid content and preferential beta-oxidation of arachidonic acid over palmitic acid in tumour cell lines as compared to normal lymphoid cells.

In several studies certain polyunsaturated fatty acids (PUFA) have been shown to be selectively tumouricidal or suppressive of tumour cell proliferation. The mechanism behind this phenomenon likely involves peroxidation of the PUFA and generation of free radicals to which tumour cells seem to be more sensitive than normal cells. In this report we have measured the total lipid content in separated lymphoid cells and several tumour cell lines, among which, T-cell leukaemia, monocytic leukaemia, melanoma, fibrosarcoma, lung carcinoma and colon adenocarcinoma are included. Generally these tumour cell lines contain only one half to one third of the relative amount of arachidonic acid (AA) as compared to freshly prepared lymphocytes and monocytes or lymphocytes kept in culture. Furthermore, when we measured the beta-oxidation in long term incubation of [1-14C] AA and compared it with that of [1-14C] palmitic acid we found that several of the tumour cell lines showed a preference for AA over palmitic acid in the tumour cell lines whereas the opposite was observed for normal lymphoid cells.

Arachidonic Acid↗
PubMed1998

Changing strategies of lung biopsies in diffuse lung diseases: the impact of video-assisted thoracoscopy.

The aims of this report were: 1) to compare the strategy of bioptic approach in Italy during the last 4 yrs with a previous period; and 2) to compare efficacy and safety of video-assisted thorascopic lung biopsy (VTLB) versus OLB. We retrospectively evaluated: 1) the strategy of the bioptic approach in the Milan Sarcoid Clinic in the years 1992-1995 (201 patients) versus 1988-1991 (197 patients); and 2) data from 65 VTLB procedures in the years 1992-1995 versus 68 OLB procedures in the years 1988-1991 performed in patients with diffuse lung disease. It was found that the use of OLB (17-9%), mediastinoscopy (15-5%), and scalene node biopsy (20-7%) decreased, whereas transbronchial biopsy (TBB) increased (11-17%). VTLB biopsy is now performed in 17% of patients. VTLB compares favourably with OLB as there is less need for analgesia (7.5+/-7.5 versus 17.5+/-8.0 methadone mg i.m.: p<0.001), lower blood loss (61+/-58 versus 156+/-84 mL in the first postoperative day: p<0.001), and shorter postoperative stay (4.7+/-1.6 versus 5.7+/-1.4 days: p<0.001). Specimen adequacy (98.6 versus 985%) and diagnostic accuracy (86.1% VTLB, versus 92.6% OLB: p>0.05) were the same in the two groups. In conclusion, video-assisted thoracoscopic lung biopsy is replacing both mediastinoscopy and open lung biopsy. It is at present the best option when a surgical procedure is required for histological confirmation of diffuse lung disease.

Adult↗
PubMed1997

p-Aminobenzoic acid, but not its metabolite p-acetamidobenzoic acid, inhibits thrombin induced thromboxane formation in human platelets in a non NSAID like manner.

We have previously shown that p-aminobenzoic acid (PABA) is acetylated by several cell lines and most peripheral blood cells, including platelets, to p-acetamidobenzoic acid (PACBA). The structural similarity of PABA and PACBA to local anesthetics and some non steroidal anti inflammatory drugs urged us to perform the present investigation. When human platelets were stimulated with thrombin to liberate AA, we found that PABA inhibited the production of thromboxane (TxB2) as measured with enzyme-linked immunosorbent assay. The inhibition was reversible and observed at PABA concentrations ranging between 55 and 1000 microM. At 328 microM PABA the production of TxB2 diminished by 87% (p = 0.013). PACBA in the same doses did not affect the production of TxB2. When platelets were incubated with [1-14C]AA, in the presence of PABA, the production of [1-14C]TxB2 was only slightly inhibited, according to analysis by high pressure liquid chromatography. Obviously PABA is not mainly acting as a prostaglandin H (cyclooxygenase) or Tx synthase inhibitor. It is rather affecting a step prior to thromboxane production, most likely the liberation of the precursor AA. In conclusion, our results demonstrate for the first time that PABA, a substance occurring in nature, inhibits endogenous TxB2 synthesis in human platelets and might thus exert profound effects on platelet AA metabolism.

4-Aminobenzoic Acid↗
PubMed1997

Lipoxygenase inhibitors counteract protein kinase C mediated events in human T lymphocyte proliferation.

Four structurally unrelated inhibitors of lipoxygenase (LO), i.e. nordihydroguaiaretic acid (NDGA), Esculetin, AA861 and 5,8,11,14-eicosatetraynoic acid (ETYA) suppressed mitogen induced proliferation of human peripheral blood lymphocytes in a dose-dependent manner. The degree of suppression was influenced by the type of the mitogenic stimulus. Receptor mediated stimulation, i.e. through phytohemagglutinin or the anti-CD3 antibody OKT3, was overall less susceptible, whereas proliferation initiated by direct activation of protein kinase C (PKC), i.e. through phorbol myristate acetate or indolactam V, was profoundly suppressed (up to 90%). The effect of the LO inhibitors was not due to non-specific interference with intracellular radical intermediates, because AA861 and ETYA showed no radical scavenging activity. Two PKC inhibitors, H-7 and H-8, similarly suppressed lymphocyte proliferation and showed essentially the same suppressive pattern as LO inhibitors. The results clearly indicate that LO product(s) participate in signal transduction mechanisms in T lymphocytes, possibly via stimulation of PKC activity and cell proliferation.

Free Radical Scavengers↗
PubMed1995

Arachidonic acid is a preferred acetyl donor among fatty acids in the acetylation of p-aminobenzoic acid by human lymphoid cells.

We have previously reported that human lymphoid cells, such as peripheral blood mononuclear leukocytes (PBML) and the T-cell leukemia line Jurcat, synthesize p-acetamidobenzoic acid from p-aminobenzoic acid (PABA) and a two carbon fragment from arachidonic acid (AA), conceivably derived from beta-oxidation. Here we demonstrate that AA is a preferred substrate in this acetylation reaction over other common fatty acids such as palmitic (PA), oleic, linoleic or linolenic. This was unexpected because AA is not considered as a fuel fatty acid. In Jurcat cells, AA is also preferred as a substrate for beta-oxidation over PA. In contrast, in PBML, PA was clearly preferred as substrate for beta-oxidation over AA, in accordance with previous observations. The difference between Jurcat cells and PBML was not dependent on culture conditions, because phytohemagglutinin and interleukin-2 activated PBML, kept in culture, showed the same PA preference as freshly prepared non-activated PBML. Furthermore, we observed differences between Jurcat cells and PBML in their relative content of fatty acids and in the incorporation of PA and AA into triacylglycerols and phospholipids. Taken together, our results show differences in beta-oxidation between Jurcat cells and PBML, and suggest the involvement of peroxisomal, besides mitochondrial, beta-oxidation, in the acetylation of PABA with fatty acids as acetyl donors.

4-Aminobenzoic Acid↗
PubMed1994

Identification of a substance, previously shown to enhance mitogenesis of human lymphocytes, as the acetamide of p-aminobenzoic acid.

We characterize here an arachidonic acid (AA)-derived metabolite previously found to have an adjuvant effect in phytohemagglutinin-induced mitogenesis of lymphocytes from mothers of newborn babies and from immunodeficient infants. We named the metabolite 'compound 4' due to its position in a thin-layer chromatography system developed for isolation of eicosanoids. The compound was originally found to be produced by peripheral blood mononuclear leukocytes and the T cell leukemia line Jurcat after long-term (18-24 h) incubation with [1-14C]AA. Compound 4 is also produced by lymphocytes, monocytes, platelets, thrombocytes, cultured fibroblasts and various types of malignant cell lines. We purified this metabolite by means of high pressure liquid chromatography with synchronous detection of radioactivity and measurement of ultraviolet-light absorption at 278 nm. Proton nuclear magnetic resonance spectroscopy and mass spectrometry with electron impact techniques demonstrated that compound 4 is not an eicosanoid, but is identical to p-acetamidobenzoic acid (PACBA). The cells synthesize PACBA from p-aminobenzoic acid and a two-carbon residue from AA.

4-Aminobenzoic Acid↗
PubMed1991

Biological profile of FCE 24517, a novel benzoyl mustard analogue of distamycin A.

FCE 24157 (chemically (beta-[1-methyl-4-(1-methyl-4--[1-methyl-4-(4-N,N- bis(2-chloroethyl) amino-benzene-1-carboxy-amido) pyrrole-2-carboxiamido]pyrrole-2-carboxyamido)pyrrole-2-c arboxyamido]) propionamidine, hydrochloride) is a distamycin A (Dista A) derivative bearing a benzoyl mustard moiety instead of the formyl group at the N-terminal. Contrary to Dista A, FCE 24517 has been found to display potent cytotoxic activity on human and murine tumour cell lines. The compound maintains activity on melphalan (L-PAM)-resistant cells, whereas cross-resistance is observed on doxorubicin-(DX)-resistant cells. In vivo, FCE 24517 was found to possess evident antineoplastic activity on a series of murine transplanted solid tumours and human tumour xenografts. The following neoplasms were in fact found to be sensitive to FCE 24517 treatment: M14 human melanoma xenograft, N592 human small cell lung carcinoma, MTV murine mammary carcinoma, Colon 38 murine carcinoma, PO2 murine pancreatic carcinoma and M5076 murine reticulosarcoma. Lower effectiveness was observed against the murine P388 and Gross leukaemia, Lewis lung murine carcinoma, LoVo human colon carcinoma xenografts and A459 human lung adenocarcinoma. Against the murine L1210 leukaemia, FCE 24517 displayed a clear activity only when the tumour was transplanted i.p. and treatment was given i.p., whereas only marginal activity was seen against this leukaemia if transplanted i.v. and the drug was given i.v. As true also in vitro, FCE 24517 was effective against i.p. implanted L1210 leukaemia resistant to L-PAM. The mode(s) of action of this new compound is under active investigation.

Animals↗
PubMed1989

Emergency laser vaporization and helium-oxygen administration for acute malignant tracheobronchial obstruction.

Two patients with malignant airway obstruction and acute respiratory insufficiency were given emergency treatment with yttrium aluminum garnet (YAG) laser tissue vaporization under local anesthesia only. A mixture of oxygen and helium was administered to reduce the respiratory distress. This case emphasizes the rapidity and effectiveness of YAG laser treatment via fiberoptic bronchoscopy under local anesthesia in the management of acute malignant airway obstructions.

Adult↗
PubMed1989

Typical and atypical bronchial carcinoids.

From January 1955 to April 1987 111 patients with bronchial carcinoid were operated on in our department. There were 62 males and 49 females with a mean age of 45.5 years. Preoperative histological diagnosis was achieved in 22 cases, while in five patients, a false positive diagnosis of small cell lung cancer was reported. Fifteen patients required pneumonectomy, 70 had lobectomy, 16 bilobectomy, and four segmentectomy. One patient required tracheal resection, while in another patient the tumour was removed through bronchotomy. Four patients were completely treated with YAG laser phototherapy. There were three postoperative deaths. The following variables were analysed and discussed in order to evaluate their influence on prognosis: (1) size of the tumour, (2) typical or atypical appearance, (3) endoluminal or extraluminal growth, (4) vascular invasion, (5) node metastases. Atypical onset, node metastases and extraluminal invasion are significant factors in worsening the prognosis.

Adolescent↗
PubMed1989

Synthesis, DNA-binding properties, and antitumor activity of novel distamycin derivatives.

A group of potential alkylating agents have been synthesized that are structurally related to the oligopeptide antiviral antibiotic distamycin. All derivatives form complexes with native calf-thymus DNA but compounds 2, 3, and 6 give rise to covalent adducts. Cytostatic activity against both human and murine tumor cell lines in vitro is displayed by the new compounds. Compounds 3 and 4 are active on melphalan-resistant L1210 leukemia in mice.

Alkylating Agents↗
PubMed1988

Surgical therapy in lung cancer with single brain metastasis.

From January 1975 to April 1987, 27 patients underwent surgical resection of non oat cell lung cancer and a single brain metastasis. There were 25 men and 2 women ranging in age from 37 to 70 years. In 21 cases the brain metastasis was synchronous while in 6 cases the onset was metachronous. In 17 cases, the site of the brain metastasis was supratentorial and in 10 cases it was located in the posterior fossa. The chest X-ray confirmed the primary lung tumour in 24 cases. In 3 cases, only bronchoscopy and cytology revealed the primary focus of the tumour. The lung cancer was located in the upper lobe in 25 patients. Upper lobectomy was performed in 23 patients, pneumonectomy in 3, and lower lobectomy in 1. There were no operative deaths. The cell type was adenocarcinoma in 19 cases, squamous cell carcinoma in 4 patients and large cell carcinoma in 4. Only the tumour and nodes were used for staging at thoracotomy. The classification was: 12 patients in stage I, 2 in stage II, and 13 in stage III. At conclusion of the study the longest survival was 68 months after thoracotomy. There was no significant difference in the duration of survival in patients over or under 50 years old. Better results were obtained in patients without node metastases at thoracotomy (median survival of 30 months and an overall 5-year survival of 35%), and in patients with supratentorial metastases (median survival of 22 months and an overall 5-year survival of 23.4%). Our experience confirms that combined surgery prolongs survival and improves the quality of life.

Adult↗