Implant insertion torque value in immediate loading: A retrospective study.

BACKGROUND: The aim of this study is to verify if the Insertion Torque Value (ITV) of 32 Ncm for immediate loading protocol (ILP), as indicated by literature, is still, with the advance in implant research, a real significant cut-off for long-term implant survival. MATERIAL AND METHODS: In this retrospective study, data from 224 patients that during three years of clinical practice, were submitted to the insertion of 322 implants with immediate loading protocol, have been recorded, pooled and analyzed. Data were organized based on Insertion Torque Value (ITV): > 32 Ncm (CG) and < 32 Ncm (LTG) and two different groups of equal sample size, 161 implants each, were distinguished. Crestal bone reabsorption, and the implant failure rate were evaluated after 2-years of follow-up. RESULTS: The bone reabsorption in LTG (0.49 ± 0.11 mm ) was significantly greater than CG (0.22 ± 0.04 mm), p<0.001. However, the survival rate after 2-years of follow-up was quite high and similar for both groups: 96.89% for LTG and 97.52% for CG and no statistically significant differences have been found among the two groups for the implant failure rate (p=0.455).The Odds Ratio (OR) of implant failure was of 1.258 (95% CI 0.332, 4.772), but results were not statistical significant, p=0.740. CONCLUSIONS: The present study showed that although implants with ITV> 32 Ncm are still characterized by a lower crestal bone resorption, there are no statistically significant differences among the two groups for what concerning the failure rate during the 2 years of follow-up and OR. These results permit us to suppose that the cut-off of ITV >32 Ncm for immediate loading implants, could be reduced to inferior values. However further studies are necessary to indicate precise clinical guidelines.

Time course analysis of brachial artery flow mediated dilatation in subjects with gingival inflammation.

AIM: Several investigations report an inverse association between periodontal disease and endothelial function measured by brachial artery Flow-Mediated-Dilatation (FMD) technique. These studies examined endothelial function by using the traditional approach to FMD calculation, that is from diameters assessed at 60 seconds after deflation. Nevertheless, possible relationship between gingival inflammation and endothelial dysfunction observed over this temporal threshold remains still unexplored. The purpose of our study was to explore the relationship between gingival inflammation and endothelial function, by considering the time course of brachial FMD. METHODS: Forty-six free-living white subjects, participating in a cardiovascular disease prevention campaign, were enrolled. FMD was measured at 60s and at 2 and 3 min after forearm ischemia. Maximal FMD was calculated (Peak FMD), for each patient. Gingival Index (GI) was evaluated as measure of gingival inflammation. RESULTS: In univariate analyses, GI was associated with both FMD at 60 sec (r=-0.30, P=0.038) and Peak FMD (r=-0.41, P=0.004). In multiple regression analyses including GI, age, gender, and known risk factors for atherosclerosis, only GI and age were independently and inversely associated with Peak FMD and FMD at 60 s, but this association was stronger with Peak FMD. Moreover, when we divided subjects on the basis of GI value, patients with GI > 1 presented lower Peak FMD and higher prevalence of absent FMD. CONCLUSION: The present study extends previous observations about the negative effects of periodontal disease on endothelial function, highlighting the importance of the evaluation of time course of vascular reactivity.

Medroxyprogesterone acetate increases anthracyclines uptake in chronic lymphatic leukemia cells: role of nitric oxide and lipid peroxidation.

Anthracyclines are one of the most used drugs in the therapy of several malignant tumors. Unfortunately, its use is still limited by their cardio-toxicity and by the presence of cancer cells resistant to these drugs. In the present study we evaluated the ability of a chemo-sensitizer agent, MPA (Medroxyprogesterone Acetate), to modify anthracyclines intranuclear uptake in normal leukocytes (NL) and in chronic lymphatic leukemia leukocytes (CLL). Moreover we evaluated the role of lipid peroxidation and nitric oxide (NO) production on antracyclines activity and on their combination with MPA. Our data show that MPA significantly increases anthracyclines uptake only in CLL cells and decreases anthracyclines induced lipid peroxidation.

A new cacospongionolide derivative from the sponge Fasciospongia cavernosa.

Cacospongionolide F (4a), a new bioactive cacospongionolide-related sesterterpene, has been isolated from the Northern Adriatic sponge Fasciospongia cavernosa. The structure was proposed on the basis of spectroscopic data and chemical transformations. The absolute configuration was established using the modified Mosher's method. A molecular mechanics study of the dehydrodecalin ring explained the observed differences in dynamic behavior between cacospongionolide F and mamanuthaquinone, a related compound. Antimicrobial activity, brine shrimp and fish lethalities of this new compound are reported.

Ovarian function suppression with a GnRH analogue: D-ser(But[t])[6]-Arzgly[10]-LHRH (Goserelin) in hormone dependent canine mammary cancer.

Hormones and hormone level modifying substances have long been used to treat hormone-dependent tumours in humans. Recently, attempts have been made to use hormone manipulation regimens for the treatment of these tumours in veterinary medicine. The aim of the present study was to evaluate the activity of the luteinizing hormone-releasing hormone (LHRH)-agonist, D-ser(But[t])[6]-Azgly[10]-LHRH (Goserelin) in hormone-dependent mammary cancer in dogs. Eighteen female dogs with hormone-dependent mammary cancer (T2-T4, N0, M0 according to TNM clinical staging classification) were selected and allocated into two groups: nine dogs not treated with Goserelin (Group 1) referred to as control; and nine dogs treated with 60 microg/kg depot Goserelin every 21 days for 12 months (Group 2). Goserelin treatment decreased circulating levels of oestradiol and progesterone and reduced the size of mammary tumours; all the animals showed objective response (OR) to treatment after 3 months, and the relapse-free survival after 2 years was 88%. Haematology and blood chemistry parameters, measured every month from the beginning of treatment, as well as physical examination, showed that the drug was without toxic effects. This suggests that, at the dose administered, Goserelin blocks the hypothalamus-pituitary-ovary axis, and consequently can be useful to treat hormone-dependent mammary tumours in female dogs.

A new cacospongionolide inhibitor of human secretory phospholipase A2 from the Tyrrhenian sponge Fasciospongia cavernosa and absolute configuration of cacospongionolides.

A new inhibitor of human secretory phospholipase A2 (PLA2), cacospongionolide E (4a), has been isolated from the Tyrrhenian sponge Fasciospongia cavernosa. The structure was proposed on the basis of spectroscopic data and by chemical transformations. The absolute configuration of cacospongionolides 2a-4a was established using the modified Mosher's method. Cacospongionolide E was the most potent inhibitor toward human synovial PLA2, showing higher potency than the reference compound manoalide and exerting no signs of toxicity on human neutrophils. It showed high activity in the Artemia salina bioassay and moderate toxicity in the fish (Gambusia affinis) lethality assay.

Modification of membrane fluidity and depolarization by some anthracyclines in different cell lines.

One of the major problems in cancer treatment is the progressive desensitization of cancer cells to chemotherapeutic drugs. Several hypotheses have been advanced to explain this property of cancer cells. In recent years different calcium channel blockers and other chemosensitizing agents like synthetic progestins have been used to revert drug resistance. In our experiments we evaluated the effects of Doxorubicin and Idarubicin on membrane fluidity and depolarization using normal lymphocytes, chronic lymphatic leukemia lymphocytes, normal breast and hormone dependent breast cancer cells and cardiomyocytes. The drugs were used alone or in combination with Verapamil and Medroxyprogesterone acetate. We showed that MPA enhances DOXO and IDA biochemical effects, acting not only on the membrane lipid bilayer, but also on ion channels. VERA instead does not seem to act through the same mechanism.

Preliminary observations on the interference of antiblastic agents in membrane fluidity and leukocyte potential.

A major problem in cancer treatment is the progressive desensitization of the cancer cells to chemotherapeutic drugs. Several hypotheses have been advanced to explain this property of neoplastic cells. In recent years, some calcium-channel blockers have successfully been used to restore drug-sensitivity in previously resistant tumors. The presence of a correlation between ion channels and membrane fluidity is well known. In the ambit of our studies on the activity of several chemotherapeutic drugs on tumors, we have studied the variations in membrane depolarization and fluidity in some leukemic cells as a result of polychemotherapeutic treatments. Our results demonstrate that the membrane fluidity and K(+)-induced depolarization of some types of leukemic cells in patients untreated and treated with some chemotherapeutic agents, are altered significantly as compared to those of normal leukocytes.

Effect of cis-diamminedichloroplatinum (II) on rat thymocyte membrane potential.

The effect of cis-diamminedichloroplatinum (II) (cisDDP) on rat thymocytes has been investigated. Changes of anisotropy constant and depolarization of the cell membrane have been determined. The effect of cisDDP on the anisotropy constant has been observed on treated animal thymocytes but not on treated isolated cell membranes. CisDDP inhibits KCl-induced depolarization in isolated rat thymocytes. This inhibiting effect is still present at a concentration as low as 5 microM and it is dose-dependent with a 9.6 microM ED50. CisDDP also boosts the inhibition of the polarization caused by 10 microM tetrodotoxin (TTX) and 10 microM doxorubicin (DOXO). The replacement of Na+ by choline and the inactivation of Ca2+ by EGTA, in the incubation medium, reduces the inhibiting effect of cisDDP on the KCl-induced depolarization. These results suggest that cisDDP induced alterations could be due to the interference of cisDDP with the activity of the ionic channels pertaining to Na+ and Ca2+. This interference is stronger for Na+ channels.

Cacospongionolide B, a new sesterterpene from the sponge Fasciospongia cavernosa.

Cacospongionolide B [2a], a new cacospongionolide-related sesterterpene, has been isolated from the Adriatic sponge Fasciospongia cavernosa. The structure was elucidated by spectral and chemical means. The antimicrobial activity and brine shrimp and fish lethalities of 2a are reported.

A new scalarane sesterterpenoid from the marine sponge Cacospongia mollior.

A new sesterterpene, 12-deacetoxyscalaradial [2a] has been isolated from the sponge Cacospongia mollior, together with the previously described scalaradial [2b] and furoscalarol [3]. The structure of the new compound, proposed by spectral data, was confirmed by X-ray diffraction analysis. Compound 2a is the first scalarane sesterterpenoid, without a substituent at C-12, to have been identified in nature. It shows high antifeedant activity and is hot to taste for the human tongue. Both 2a and 2b display cytotoxic activity.

4-acetylaplykurodin B and aplykurodinone B, two ichthyotoxic degraded sterols from the Mediterranean mollusk Aplysia fasciata.

Two ichthyotoxic lactones, 4-acetylaplykurodin B [1] and aplykurodinone B [2], were isolated from the external parts of the body of the mollusk Aplysia fasciata. Their structures, determined by spectroscopic and chemical means, are closely related to aplykurodin B [3] previously isolated from Aplysia kurodai. The interconversion of delta- and gamma-lactones in the aplykurodin derivatives has been also investigated.

A novel multifunctional metabolic pathway in a marine mollusc leads to unprecedented prostaglandin derivatives (prostaglandin 1,15-lactones).

The discovery of high levels of prostaglandin (PG) 1,15-lactones of both the E and F series and their co-existence with PGs has been recently described in the opisthobranch mollusc Tethys fimbria. The present study was undertaken in order to investigate the biosynthesis of these novel natural PG derivatives in vivo using radiolabelled precursors, and to gain a preliminary understanding of their biological role. PGE2 1,15-lactone was shown to be produced from both PGE2 and PGF2 alpha in the mollusc mantle and appeared to be quickly transferred to the mollusc dorsal appendices (cerata). The detachment of the latter during the typical defence behaviour of T. fimbria was accompanied by the conversion of PGE2 and PGE3 1,15-lactones back to the corresponding PGs. Both PGE2 and PGE2 1,15-lactone were also shown to be biosynthesized from arachidonic acid. Lactones of the F series were present as 11-acetyl derivatives in T. fimbria mantle and as 9- and 11-fatty acyl esters in the mollusc egg-mass and reproductive gland, and their biosynthesis from PGF2 alpha was demonstrated in all of these tissues. A multiple biological role of PG 1,15-lactones in T. fimbria defensive behaviour, smooth muscle contraction and egg production/fertilization control is hypothesized. The high amounts of PG derivatives found in T. fimbria and the biosynthetic studies described herein indicate that this marine mollusc may be a useful model for future studies on PG biosynthesis.

A marine mollusc provides the first example of in vivo storage of prostaglandins: prostaglandin-1,15-lactones.

Prostaglandin-(PG) 1,15-lactones and, in smaller amounts, free acids, were isolated from both the mantle and the dorso-lateral appendices of the opisthobranch mollusc Tethys fimbria. In vivo conversion of PGs into the corresponding lactones and accumulation of PGE2- and PGE3-1,15-lactones in the appendages were shown. The detachment of these appendages from the molested mollusc caused the in vivo conversion of PGE2- and PGE3-lactones back to PGE2 and PGE3 respectively, thus providing the first example of a mechanism by which prostaglandins can be stored and, when needed, released.

Oxytoxins, bioactive molecules produced by the marine opisthobranch mollusc Oxynoe olivacea from a diet-derived precursor.

The ethereal extract of the mucous secretion from the opisthobranch mollusc Oxynoe olivacea was examined and found to contain two novel ichthyotoxic compounds, named oxytoxin 1 and 2 (1,2). The structures of 1 and 2 are closely related to the metabolites previously isolated from the alga Caulerpa prolifera. The activity of the most stable compound was studied in order to investigate the possibility of a further biological role for these metabolites, which represent an uncommon example of bioactive molecules produced in vivo from a dietary precursor.

A new bioactive derivative of avarol from the marine sponge Dysidea avara.

A new derivative of avarol, monoacetyl avarol, has been isolated from the sponge Dysidea avara. The structural elucidation and biological activities are reported.

Effects of medroxyprogesterone acetate on DMBA-induced mammary tumors.

Rats with DMBA-induced mammary tumors were treated for 30 days i.m. with medroxyprogesterone acetate (MPA) at doses of 7.5, 15 or 75 mg/kg. Complete regression (disappearance of tumor) was observed in 60% and 20% of tumors from rats treated with 75 or 15 mg/kg MPA respectively. Partial regression (50% decrease in tumor area) was found in the remaining 20% of tumors from rats treated with 15 mg/kg MPA. The dose of 7.5 mg/kg MPA resulted in being devoid of effectiveness. Estrogen receptor (ER) levels were significantly reduced at all doses of MPA injected both in responsive and non-responsive tumors. However, only tumors with ER levels above 15 fmol/mg before therapy resulted in being responsive to MPA treatment. Progesterone receptors were so reduced at the end of the experiment as to not be detectable in all treated groups. It was concluded that MPA is effective as an antitumoral drug also in DMBA-induced mammary tumors and that this effect is at least in part related to ER levels before treatment.

Effects of bromocriptine on adenylate cyclase and phosphodiesterase activities of rat striatum.

The activity of 2-bromo-alpha-ergokryptine (bromocriptine) (5 mg kg-1, i.p.) on adenylate cyclase and on phosphodiesterase (PDE-PDE II) of rat striatum, has been examined both in vitro and in vivo. In vitro and in vivo bromocriptine stimulated adenylate cyclase activity, but reduced the stimulating effect of dopamine on adenylate cyclase activity. Bromocriptine showed a dose-dependent biphasic action on phosphodiesterases in vitro while in vivo it stimulated them. The results obtained proved bromocriptine to have an agonist-antagonist action at striatal dopamine receptor level, with a relevant effect on the cAMP system.