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Biomedical subjects

C Bertoli

Publications and source records attributed to C Bertoli.

9 recordsLinked to original sources

Ceramide triggers an NF-kappaB-dependent survival pathway through calpain.

We have shown that C2 ceramide, a cell-permeable analog of this lipid second messenger, triggers an NF-kappaB dependent survival pathway that counteracts cell death. Activation of NF-kappaB and subsequent induction of prosurvival genes relies on calpain activity and is prevented on silencing of the calpain small subunit (Capn4) that is required for the function of ubiquitous calpains. We have demonstrated that p105 (NF-kappaB1) and its proteolytic product p50 can be targets of micro- and milli-calpain in vitro and that a p50 deletion mutant, lacking both the N- and the C-terminal ends, is resistant to calpain-mediated degradation. Capn4 silencing results in stabilization of endogenous p105 and p50 in diverse human cell lines. Furthermore, p105 processing and activation of NF-kappaB survival genes in response to C2 ceramide is impaired in Capn4-/- mouse embryonic fibroblasts defective in calpain activity. Altogether, these data argue for the existence of a ceramide-calpain-NF-kappaB axis with prosurvival functions.

Animals↗

Dentin bond strengths as a function of solvent and glutaraldehyde content.

PURPOSE: To evaluate the effect of the inclusion of glutaraldehyde on the shear bond strength of new ethanol-based adhesives (Gluma Comfort Bond & Desensitizer, GCBD and Gluma Comfort Bond, GCB) versus acetone-based Gluma One Bond (GOB) and a conventional three-step adhesive as a control. MATERIALS AND METHODS: Forty bovine incisors were mounted in acrylic, polished to 600-grit, and randomly assigned to four groups (n=10). Dentin was etched for 15 s using 35% phosphoric acid, rinsed, and lightly dried. After adhesive application and curing, Charisma composite was applied in a #5 gelatin capsule and light-cured. Specimens were loaded in shear using an Instron at 5 mm/min. Shear bond strengths were calculated by dividing failure load by bonded surface area. ANOVA showed a significant difference in means at P< 0.01, so Tukey's test was used for pairwise comparisons. RESULTS: Mean SBS (+/- SD, MPa) were: GOB: 8 (4.4)ab; GCB: 10 (4.4)ab; GCBD: 14 (6)bc; SBMP: 17.7 (6.4)c. Superscript letters indicate Tukey's homogeneous subsets (P< 0.05).

Acetone↗

Interaction between the HPV-16 E2 transcriptional activator and p53.

The HPV-16 E2 protein is a major regulator of viral DNA replication and gene expression. Through interactions with the viral origin binding protein, E1, it localizes E1 to the origin of replication and stimulates the initiation of viral DNA replication. However, several recent reports have described a number of diverse activities of E2 relating to the induction of apoptosis through both p53 dependent and independent mechanisms, and to induction of growth arrest in both the G1 and G2M phases of the cell cycle. Recent studies have also shown that p53 can specifically inhibit HPV DNA replication, albeit through an unknown mechanism. Since p53 has been described in the replication centres of Herpes Viruses, Adenovirus and SV40 we decided to investigate whether any of the above activities of E2 may be related to an association with p53. We show, in a series of in vitro assays, specific interaction between p53 and HPV-16 E2 via residues in the carboxy terminal half of the E2 protein. Mutational analysis of p53 indicates that sequences in both the DNA binding and oligomerization domains are essential for the interaction, and a mutant of p53 which is unable to bind E2 is also unable to inhibit HPV DNA replication. Finally, using an inducible system of p53 expression we also show that E2 will complex with p53 in vivo. These results raise the intriguing possibility that p53 may also be involved in HPV DNA replication centres, and also provides explanations for some of the diverse activities reported for the HPV E2 proteins.

Amino Acid Sequence↗

Advantages of spinal anesthesia in abdominal gynecologic surgery.

The advantages obtained in vaginal surgery and caesarean section using spinal anesthesia led us to test this anesthesia to verify feasibility, problems and advantages in abdominal surgery. Spinal anesthesia was performed in 60 patients between 21 and 87 years of age. Thirty-seven total abdominal hysterectomies with or without adnexectomy, 5 laparotomic miomectomies, 3 adnexectomies, 5 colposacropexies, 2 hysterectomies with lymphadenectomy, 7 Burch colposuspension with or without hysterectomy and 1 laparoscopy for sterilization were performed. No significant problems during surgery and the postoperative period were observed. Resumption of the different physiologic functions were more rapid, hospital stay shorter and compliance greater than with general anesthesia.

Adnexa Uteri↗

The effect of fuel composition on the mutagenicity of diesel engine exhaust.

The effect of fuel composition on the mutagenicity of diesel engine emission was investigated. To this end, a fuel matrix comprising fuels with different contents of aromatic and naphthenic compounds was used. Extracts of the organic phase of raw exhausts obtained with different fuels were tested for mutagenicity in bacterial reversion assays. The results obtained demonstrate that the mutagenicity of diesel exhaust is largely dependent on the aromatic content of the fuel. In fact, mutagenicity was greatly reduced when the aromatic content of the fuel was lowered by hydrogen treatment. Conversely, mutagenicity was enhanced when the fuel was enriched with fractions of di- or triaromatic compounds. The addition of di- and trinaphthenic compounds only produced borderline mutagenicity. No clear relationship was observed between sulfur content of the fuel and mutagenicity of the exhaust. Assays in bacterial strains with different sensitivity to nitroaromatic compounds suggest a low contribution of the highly mutagenic dinitropyrenes to the responses observed, and a relatively greater contribution of 1-nitropyrene or other nitroaromatics processed by the same bacterial nitroreductase.

Mutagenicity Tests↗

Giant parathyroid adenoma demonstrated by dual tracer parathyroid imaging.

Noninvasive diagnostic imaging modalities have played an increasingly important role in preoperative localization of parathyroid lesions. The radionuclide method using TI-201 and Tc-99m subtraction imaging is quite successful in detecting such lesions, with a reported sensitivity of 92%. A case of surgically proven primary hyperparathyroidism, caused by an unusually large parathyroid adenoma and detected by the dual tracer method, is presented.

Adenoma↗