Long-term survival rate of implants placed in conjunction with 246 sinus floor elevation procedures: results of a 15-year retrospective study.

OBJECTIVES: The aim of the present long-term study was to retrospectively evaluate the survival rate of implants placed in regenerated maxillary sinuses and to assess the influence of hypothetical predictors of implant failure. METHODS: A database including 218 patients who received dental implants after sinus lift procedures was analyzed. The following variables were systematically included and evaluated: type of graft material used, number of surgeries performed, and use of membranes to cover the lateral antrostomy and/or to repair accidental Schneiderian membrane perforations. The Kaplan-Meier estimator was used for comparisons among the groups. RESULTS: A total of 589 dental implants were positioned in 246 grafted sinuses and were in function for 3-186 months. The Kaplan-Meier cumulative survival rate was 98.3% after 15.5 years of follow-up. All implant losses occurred within 52 months (4.3 years) after augmentation. According to the log-rank test, no statistically significant difference was shown between each patient/implant variable (p>0.05). CONCLUSIONS: Despite the limitations inherent in this type of study, no statistically significant differences between the groups could be found. Intraoperative Schneiderian membrane perforations did not affect the outcome of the implants positioned. CLINICAL SIGNIFICANCE: The present long-term study is intended as a reference for clinicians approaching sinus floor elevation surgery in order to provide them with relevant operative findings. Since all the drawbacks occurred within the first 5 years, medium-term follow-up studies could be suitable for further retrospective evaluations.

Hepatocyte odd protein shuttling (HOPS) is a bridging protein in the nucleophosmin-p19 Arf network.

Nucleophosmin (NPM), a ubiquitously and abundantly expressed protein, occurs in the nucleolus, shuttling between the nucleoplasm and cytoplasm. The NPM gene is mutated in almost 30% of human acute myeloid leukemia cells. NPM interacts with p53 and p19(Arf), directs localization of p19(Arf) in the nucleolus and protects the latter from degradation. Hepatocyte odd protein shuttling (HOPS) is also a ubiquitously expressed protein that moves between the nucleus and cytoplasm. Within the nucleus of resting cells, HOPS overexpression causes cell cycle arrest in G0/G1. HOPS knockdown causes centrosome hyperamplification leading to multinucleated cells and the formation of micronuclei. We demonstrate a direct interaction of HOPS with NPM and p19(Arf), resulting in a functionally active trimeric complex. NPM appeared to regulate HOPS half-life, which, in turn, stabilized p19(Arf) and controlled its localization in the nucleolus. These findings suggest that HOPS acts as a functional bridge in the interaction between NPM and p19(Arf), providing new mechanistic insight into how NPM and p19(Arf) will oppose tumor cell proliferation.

Chromatin sphingomyelin changes in cell proliferation and/or apoptosis induced by ciprofibrate.

It has been shown that neutral-sphingomyelinase and sphingomyelin-synthase activities are present in chromatin and they modify the sphingomyelin (SM) content. The activity of the first enzyme is stimulated and the second inhibited, when the hepatocytes enter into the S-phase after partial hepatectomy, thus suggesting that ceramide may have a pivotal role in cell proliferation. An opposite function was attributed to ceramide in hepatocytes which undergo apoptosis after lobular ligature. In order to clarify this point, a model was developed in which the same liver cells undergo proliferation followed by induced apoptosis. To this purpose, the rats were treated for 7 days with ciprofibrate and then left without treatment for 4 days. During the treatment, the peroxisome enzyme markers increase their activity and the number of proliferating cells increases, reaching a maximum after 3 days of treatment, as shown by the number of cells positive for the proliferating cell nuclear antigen. At the same time, the chromatin sphingomyelinase activity reaches the maximum, while a similar increase is not found in the cytoplasm or in the isolated nuclei. On the contrary, SM-synthase activity is depressed in chromatin, but not in the nuclei in which a peak is shown after 3 days of ciprofibrate treatment. After drug withdrawal, the hepatocytes undergo apoptosis as confirmed by the increase of Bax and tissue transglutaminase (tTGase) expression; the chromatin SM increases as a consequence of an increase of SM-synthase activity. It can be hypothesised that chromatin SM may have a role in cell duplication by influencing the chromatin structure stability.

Two dosage interferon-alpha 2b maintenance therapy in patients affected by low-risk multiple myeloma in plateau phase: a randomized trial.

BACKGROUND AND OBJECTIVE: The role of interferon (IFN) in the remission phase of multiple myeloma (MM) is still an open question, particularly for its scheduling and the subset of patients who could benefit from this approach. The present randomized multicenter study was designed to compare two schedules of IFN maintenance therapy in order to assess the difference in effectiveness and tolerance. DESIGN AND METHODS: This prospective randomized multicenter study was attempted to assess the best schedule of IFN administration in the maintenance treatment of MM in plateau phase with regard to progression free survival (PFS) and toxicity. The second aim was defining the difference between the two schedules in overall survival (OS) and identifying the critical dose of IFN therapy needed to prolong plateau phase and survival. We enrolled 52 patients affected with low-risk MM (i.e. with serum beta 2-microglobulin < 6.0 mg/L and serum albumin > 3.0 g/dL); 27 patients (group A) were randomly assigned to receive IFN alpha-2b 3 megaunits (MU) subcutaneously three times a week and 25 patients (group B) 3 MU/day until disease progression. RESULTS: Median progression free survival (PFS) was 11.9 months in group A and 38.3 months in group B (p = 0.0038). Median survival was 63.2 months in group A and 61.9 months in group B (p = 0.489). However, those patients who were given an IFN dose > or = 30 MU/month experienced a significantly longer PFS and survival than the other patients. Seventeen patients (32.7%) discontinued therapy and sixteen patients (30.8%) reduced IFN alpha-2b dose because of severe side effects without having a significant difference between the two schedules. INTERPRETATION AND CONCLUSIONS: Our results show that patients treated with IFN alpha 3 MU/day had a significantly longer remission duration than patients treated with IFN alpha 3 MU three times weekly. Moreover, an IFN dose is probably critical for obtaining a longer survival in patients affected with low-risk MM. Since the patients' discomfort during a IFN maintenance therapy was frequently experienced the quality of their lives should be carefully taken into account.