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Biomedical subjects

M Bucci

Publications and source records attributed to M Bucci.

At least 73 records · Page 4Linked to original sources
PubMed1995

Role of the pyrimidine-rich tract on the translation of 'chimeric' polio-hepatitis A mRNAs with engineered 5'-terminal untranslated regions.

The 5'-terminal untranslated region (5'-UTR) of picornavirus RNA contains a series of cis-acting elements required for the internal initiation of translation, including a pyrimidine-rich tract (PRT), which in entero- and rhinoviruses is located about 20 nts upstream from a silent AUG triplet in the vicinity of the translation initiation site. In hepatitis A virus (HAV) RNA, the PRT is only 12 nts upstream from the legitimate AUG initiation codon, and a second, longer PRT in a region far removed from the translation initiation site. This 5'-distal PRT includes a 'core' sequence 80% homologous to the PRT of poliovirus RNA. A 'chimeric' polio-hepatitis A mRNA was constructed in which the sequences extending between nucleotides 45 and 156 of HAV RNA replaced the corresponding ones in poliovirus 5'-UTR. The construction was extended with poliovirus sequences up to position 1809. The recombinant mRNA so generated carried two copies of the PRT. In vitro translation in lysates of truncated poliovirus mRNAs generated a single peptide of Mr = 39 kDa, while the chimeric mRNA generated a series of short peptides as a result of fortuitous (or aberrant) initiation events. A more extensive substitution in the chimeric 5'-UTR which removed the 3'-most PRT brought by the poliovirus sequences, restored the translation at the authentic initiation site. Point mutations were engineered in the 5'-most PRT of the chimeras, and bi-cistronic plasmids were constructed in which either the parental poliovirus 5'-UTR or the chimeric ones were introduced in the intergenic region. Upon transfection of COS-1 cells, the chimeric polio-hepatitis A 5'-UTR containing two PRTs did not express the reporter gene. Removal of the 3'-distal PRT or point mutations engineered into the 5'-most PRT partially restored the transient expression of the reporter gene, consistent with the notion that a single (and only a single) functionally active PRT in a proper context is required to secure the internal initiation of translation of bi-cistronic mRNAs in vivo.

Base Sequence↗
PubMed1994

The receptor-recycling and lysosome biogenesis mutant TfT1.11 belongs to a new complementation group, End6.

We have previously isolated a Chinese hamster ovary (CHO) mutant with a temperature-dependent pleiotropic defect in receptor recycling. This mutant, TfT1.11, has also been shown to have defects in fluid-phase endocytosis and lysosome biogenesis. Previously isolated CHO cell mutants with defects in endocytosis have been assigned to five recessive complementation groups (End1-End5). We have performed complementation analysis using polyethylene glycol-induced fusion of genetically marked sublines of TfT1.11 with representative mutants from each of the End groups. Complementation of the receptor trapping and lysosome biogenesis defects as well as temperature lethality was observed with all groups, demonstrating that TfT1.11 defines a new complementation group, End6.

Animals↗
PubMed1990

A prospective evaluation of a simplified captopril test for the detection of renovascular hypertension.

Renovascular hypertension is potentially curable but of low prevalence. A previous retrospective study has demonstrated the use of a potentiated increase in plasma renin activity after captopril administration as a diagnostic test for renovascular hypertension; this requires two blood samples for plasma renin activity determination and three inclusive criteria for a positive test result. We applied this test prospectively to screen 100 hypertensive patients for renovascular hypertension. We evaluated 29 patients with renovascular hypertension; the remainder were diagnosed as having essential hypertension. In our patient population, a postcaptopril plasma renin activity of 5.7 ng of angiotensin per milliliter per hour (ngAl.mL-1.h-1) or greater had a 100% sensitivity and an 80% specificity for renovascular hypertension. An absolute increase in plasma renin activity with captopril of 4.7 ngAl.mL-1.h-1 or greater had a lower sensitivity of 90% and a specificity of 87%, whereas a fractional increase in plasma renin activity after captopril of 150% or higher had the lowest sensitivity of 69% and a specificity of 86%. A subgroup analysis of 38 patients who were receiving diuretic therapy demonstrated that the test sensitivity was unchanged but the specificity was reduced. In conclusion, a single postcaptopril plasma renin activity value of 5.7 ngAl.mL-1.h-1 or greater is a simplified screening test for renovascular hypertension, with excellent sensitivity and acceptable specificity. This test is well tolerated, inexpensive, and easy to perform.

Captopril↗
PubMed1983

Particular features of cell-mediated immunity in patients with anaplastic gliomas. A comparison with kidney and bladder cancer patients.

The authors studied 24 patients affected by anaplastic gliomas in regard to the killer (Antibody-Dependent Cellular Cytotoxicity) and natural killer (Spontaneous Lymphocyte-Mediated Cytotoxicity) immunological functions, by counting the Cr51 release in Change liver and K 562 cell cultures, respectively. These parameters were also evaluated in 24 healthy donors as control, in 24 patients affected by bladder cancer and in nine cases of kidney cancer. Our data show, pre-operatively, a statistically significant impairment of ADCC and SLMC activity in glioma patients as compared both with controls, bladder and kidney cancer patients. The particular impairment of K and NK functions in gliomas is discussed with regard to the specific features of Central Nervous System malignancies. An improvement of ADCC activity was also found in the post-operative samples. This finding confirms other reports about partial restoring of altered immunocompetence after surgery, suggesting a link between extention of tumor mass and impaired immunological reactions.

Adult↗
PubMed1982

Immunological monitoring of patients affected by anaplastic glioma concerning in effects of surgery, radio-, and chemotherapy. A preliminary report.

The authors studied 24 patients affected by anaplastic gliomas, as regards immunology. In all of them the authors evaluated the lymphocyte subpopulation (B and T), firstly by simple lymphocyte count, secondly by studying the rosettes E-total and EAC, thirdly by stimulating the lymphocytes with mitogens phyto-haemoagglutinin-P (PHA), concanavalin A (Con A), and pokeweed mitogen (PWM), and lastly by counting the release of Cr51 in Chang liver cells culture in order to obtain antibody dependent cellular cytotoxicity (ADCC). The parameters were also evaluated after surgery and during conventional radio-chemotherapy with BCNU. Whereas the so-called B-pool seems to be unaffected, the preliminary results show that the T-pool (identified by the E-t rosettes and by responses to PHA, PWM, and ConA) is depressed to a statistically significant degree, if compared with a control group. This depression seems to be related to the tumoral mass, and it is not increased by radio-chemotherapy. In addition, ADCC also seems to be depressed in our glioma patients in comparison with a control group and witha group of bladder cancer patients.

Adult↗
PubMed1977

[Bencyclan's effects "in vitro" on fibrinolysis (author's transl)].

The eventual fibrinolytic activity of Bencyclan (N-3-(1-benzil-cicloeptil-ossi)-propil-N-N-dimetil-amino-fumarato-acid) has been studied in vitro. The presence of eventuals FDP has been calculated through the Staphylococcal clumping test (SCT), by previous incubation of blood-samples with scalar concentrations of Bencyclan. No increase in the fibrinolytic activity with regard to the incubation of samples with the above-mentioned substance has been noticed.

Bencyclane↗
PubMedDate not supplied

The effects of renal transplantation on circulating precursor dendritic cells.

BACKGROUND: Dendritic cells (DCs) are potent antigen-presenting cells that induce and regulate immune responses. Recent advances allow accurate quantification of peripheral blood (PB) myeloid and plasmacytoid DC populations (mDC and pDC, respectively), although the response to renal transplantation (RT) remains unknown. METHODS: Using flow cytometry, PBDC levels were quantified in patients with end-stage renal disease (ESRD) undergoing renal transplantation. RESULTS: PBDC levels were significantly reduced in ESRD patients pretransplantation compared to healthy controls, with further reduction noted immediately following a hemodialysis session. RT resulted in a dramatic decrease in both subsets, with a greater reduction of pDC levels. Both subset levels were significantly lower than in control patients undergoing abdominal surgery without RT. Subgroup analysis revealed significantly greater mDC reduction in RT recipients receiving antilymphocyte therapy, with preferential binding of antibody preparation to this subset. Samples from later time points revealed a gradual return of PBDC levels back to pretransplant values concurrent with overall reduction of immunosuppression. Finally, PBDC levels were significantly reduced in patients with BK virus nephropathy compared to recipients with stable graft function, despite lower overall immunosuppression. CONCLUSIONS: Our findings suggest that PBDC levels may reflect the degree of immunosuppression in renal allograft recipients. Furthermore, PBDC monitoring may represent a novel strategy to predict important outcomes such as acute rejection, long-term graft loss, and infectious complications.

Adult↗
PubMedDate not supplied

Effect of HSV-2 infection on the expression of HPV 16 genes in CaSki cells.

Human papillomaviruses (HPVs) have been proposed to be the most important etiological factors for cervical cancer although different agents may act in conjunction. Herpes simplex virus type 2 (HSV-2) infection is considered as a possible cofactor to malignant transformation. To examine the influence of HSV-2 infection on the HPV genes expression, CaSki cells bearing 60 to 600 copies of HPV-16 DNA per cell were used as a model system. Twenty hours post HSV-2 infection the mRNA transcripts for HPV-16 early (E1, E2 and E6) and late (L1) genes were analysed by RT-PCR assay. Results indicated that the level of transcription of E1, E2 and E6 genes was up to 3-fold enhanced in HSV-2 infected CaSki cells suggesting that HSV-2 infection could increase the risk of cervical cancer by overexpression of both HPV regulatory and oncogenic genes.

Cell Line, Tumor↗
PubMedDate not supplied

Treatment of long-distance intermittent claudication with pentoxifylline: a 12-month, randomized trial.

The efficacy, safety, and cost of pentoxifylline (PXF) in long-range (>400 m interval) intermittent claudication was studied comparing PXF and placebo in a 12-month study. A standardized treadmill test was performed at inclusion and at 6 and 12 months. A training plan based on walking was associated with the control of risk factor levels. Of the 194 included patients, 135 completed the study: 75 in the PXF group and 60 in the placebo group. There were 59 dropouts (due to low compliance). The authors observed a 148% increase in total walking distance (TWD) at 6 months with PXF (vs 110% with placebo; p<0.05); at 12 months, the increase was 170% with PXF (vs 131% with placebo; p<0.02). There was a 38% difference at 6 months and 39% at 12 months in favor of PXF. Treatment was well tolerated. In conclusion, PXF improved walking distance significantly better than placebo.

Aged↗
PubMedDate not supplied

Treatment of intermittent claudication with pentoxifylline: a 12-month, randomized trial--walking distance and microcirculation.

The efficacy, safety and cost of pentoxifylline (PXF) in severe intermittent claudication was studied comparing PXF and placebo in a 12-month study. A treadmill test and microcirculatory evaluation with laser Doppler flowmetry were performed at inclusion and at the end of 6 and 12 months. A physical training plan (based on walking) and reduction in risk factor levels plan was used in both groups. Of the 120 included patients, 101 completed the study: 56 in the PXF group and 45 in the placebo group. There were 19 dropouts (due to low compliance). The two groups were comparable for age, sex distribution, walking distance, and the presence of risk factors and smoking. Intention-to-treat analysis indicated a 268% increase in walking distance in the PXF group (vs 198% in the placebo group; p<0.05) at 6 months and an increase of 404% (vs 280% in the placebo group; p<0.02) at 12 months. The absolute and percent increase in pain-free walking distance (PFWD) was greater in the PXF group (p<0.05). Treatment was well tolerated. No serious drug-related side effects were observed. Microcirculatory evaluation indicated an increase in flux (p < 0.05) in the PXF group (not significant in the placebo group); the after-exercise flux (AEF) was increased (p<0.05) in both groups at 6 months but the increase in AEF was greater in the PXF group at 12 month. In conclusion, between-group analysis favors PXF considering walking distance and microcirculatory parameters. Results indicate good efficacy and tolerability.

Aged↗
PubMedDate not supplied

Clarithromycin in rheumatoid arthritis patients not responsive to disease-modifying antirheumatic drugs: an open, uncontrolled pilot study.

OBJECTIVE: In 1996 we found by serendipity that 2 patients with rheumatoid arthritis (RA) who were taking clarithromycin (CM) to eradicate Helicobacter pylori experienced a regression of their RA symptoms. Following this observation, we tested the hypothesis that this reduction in symptoms could have been caused by CM administration. METHODS: We performed a 6-month, open, uncontrolled pilot study on 18 patients (14 females and 4 males, mean age 62 yrs.) with RA who had previously received DMARDs (mean 2.6) and discontinued the treatment at least one month earlier because lack of efficacy or severe side effects. Patients were treated with CM at the dose of 500 mg twice per day for the first 10 days, followed by a daily maintenance dose of 250 mg twice per day. RESULTS: 4/18 patients did not complete the treatment, 2/18 were not responsive to the treatment and 2/18 discontinued the treatment. Following ACR criteria the improvement was: 10 patients ACR 20; 6 patients ACR 50; and 2 patients ACR 70. The remaining 4 patients did not reach ACR 20 since either the number of tender or swollen joints was not to the level required. Reductions in PGE2 and soluble phospholipase A2 plasma levels were closely related to CM plasma levels. CONCLUSIONS: Ourfindings suggest that CM treatment can be beneficial in those patients who are not responsive to or cannot tolerate DMARDs. No definitive conclusions can be drawn based on the present study, due to the small sample size involved.

Adult↗