RESUMO
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.
Assuntos
Implantes Dentários para Um Único Dente , Implantes Dentários , Carga Imediata em Implante Dentário , Implantação Dentária Endóssea , Falha de Restauração Dentária , Humanos , Estudos Retrospectivos , TorqueRESUMO
Adenylate cyclase and phosphodiesterase activities were evaluated in the striatum and hypothalamus of male rats after single treatment with different substituted benzamides (sulpiride, sultopride, tiapride, metoclopramide and bromopride) or chlorpromazine. None of the benzamides modifies the adenylate cyclase activity in the striatum but all of them stimulate this activity in the hypothalamus. The stimulating effect on the adenylate cyclase activity exerted by the in vitro addition of dopamine is not modified by the previous treatment with benzamides. Phosphodiesterase activity is not modified in the striatum, whereas it is depressed in the hypothalamus and completely inhibits the in vitro stimulating effect of dopamine.
RESUMO
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.
Assuntos
Antibióticos Antineoplásicos/metabolismo , Doxorrubicina/metabolismo , Idarubicina/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Leucócitos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Acetato de Medroxiprogesterona/farmacologia , Lipídeos de Membrana/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Óxido Nítrico/fisiologia , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Transporte Biológico/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Fenômenos Químicos , Físico-Química , Doxorrubicina/química , Doxorrubicina/farmacologia , Interações Medicamentosas , Inibidores Enzimáticos/farmacologia , Humanos , Idarubicina/química , Idarubicina/farmacologia , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucócitos/metabolismo , Malondialdeído/análise , Proteínas de Neoplasias/antagonistas & inibidores , Células-Tronco Neoplásicas/metabolismo , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase Tipo I , Nitroprussiato/farmacologia , Vitamina E/farmacologiaRESUMO
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.
Assuntos
Antraciclinas/farmacologia , Membrana Celular/fisiologia , Doxorrubicina/farmacologia , Idarubicina/farmacologia , Leucócitos/fisiologia , Fluidez de Membrana/efeitos dos fármacos , Animais , Neoplasias da Mama , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B , Leucócitos/citologia , Leucócitos/efeitos dos fármacos , Bicamadas Lipídicas , Linfócitos/efeitos dos fármacos , Linfócitos/fisiologia , Acetato de Medroxiprogesterona/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Miocárdio/citologia , Ratos , Ratos Sprague-Dawley , Células Tumorais Cultivadas , Verapamil/farmacologiaRESUMO
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.
Assuntos
Adenilil Ciclases/metabolismo , Bromocriptina/farmacologia , Corpo Estriado/enzimologia , Diester Fosfórico Hidrolases/metabolismo , Animais , Corpo Estriado/efeitos dos fármacos , Dopamina/farmacologia , Técnicas In Vitro , Cinética , Masculino , RatosRESUMO
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.
Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Timo/efeitos dos fármacos , Timo/fisiologia , Animais , Antibióticos Antineoplásicos/farmacologia , Antitoxinas/farmacologia , Doxorrubicina/farmacologia , Feminino , Técnicas In Vitro , Masculino , Ratos , Ratos Wistar , Tetrodotoxina/farmacologiaRESUMO
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.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doenças Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/tratamento farmacológico , Leucócitos/efeitos dos fármacos , Fluidez de Membrana/efeitos dos fármacos , Estudos de Casos e Controles , Doenças Hematológicas/sangue , Neoplasias Hematológicas/sangue , Humanos , Potenciais da Membrana/efeitos dos fármacosRESUMO
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.
Assuntos
Artéria Braquial , Endotélio Vascular/fisiopatologia , Gengivite/fisiopatologia , Vasodilatação , Idoso , Artéria Braquial/diagnóstico por imagem , Artéria Braquial/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estatística como Assunto , Fatores de Tempo , UltrassonografiaAssuntos
Estradiol/farmacologia , Histamina/farmacologia , Hipotálamo/efeitos dos fármacos , Receptores Histamínicos/efeitos dos fármacos , Adenilil Ciclases/metabolismo , Fatores Etários , Animais , Castração , Feminino , Hipotálamo/enzimologia , Masculino , Metiltestosterona/farmacologia , Progesterona/farmacologia , RatosRESUMO
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.
Assuntos
Neoplasias Mamárias Experimentais/tratamento farmacológico , Medroxiprogesterona/uso terapêutico , 9,10-Dimetil-1,2-benzantraceno , Animais , Citoplasma/metabolismo , Feminino , Neoplasias Mamárias Experimentais/metabolismo , Ratos , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismoRESUMO
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.
Assuntos
Moluscos/análise , Venenos de Moluscos/isolamento & purificação , Toxinas Biológicas/isolamento & purificação , Aldeídos , Animais , Dieta , Eucariotos , Espectroscopia de Ressonância Magnética , Moluscos/metabolismo , Venenos de Moluscos/metabolismo , Toxinas Biológicas/metabolismoRESUMO
A new derivative of avarol, monoacetyl avarol, has been isolated from the sponge Dysidea avara. The structural elucidation and biological activities are reported.
Assuntos
Antineoplásicos/isolamento & purificação , Poríferos/análise , Sesquiterpenos/farmacologia , Animais , Ensaios de Seleção de Medicamentos Antitumorais , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Sesquiterpenos/isolamento & purificaçãoRESUMO
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.
Assuntos
Moluscos/metabolismo , Prostaglandinas/biossíntese , Prostaglandinas/metabolismo , Animais , Ácido Araquidônico , Ácidos Araquidônicos/metabolismo , Cromatografia Líquida de Alta Pressão , Dinoprosta/metabolismo , Dinoprostona/metabolismo , Lactonas/isolamento & purificação , Modelos Biológicos , Prostaglandinas/isolamento & purificação , TrítioRESUMO
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.
Assuntos
Lactonas/metabolismo , Moluscos/metabolismo , Prostaglandinas/metabolismo , Animais , Biotransformação , Cromatografia Líquida de Alta Pressão , Lactonas/isolamento & purificação , Prostaglandinas/isolamento & purificação , Técnica de Diluição de Radioisótopos , Espectrofotometria Ultravioleta , TrítioRESUMO
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.
Assuntos
Aplysia/química , Indanos/química , Lactonas/química , Animais , Indanos/isolamento & purificação , Lactonas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Conformação Molecular , Estrutura Molecular , Rotação OcularRESUMO
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.
Assuntos
Antineoplásicos/isolamento & purificação , Homosteroides/isolamento & purificação , Poríferos/química , Terpenos/isolamento & purificação , Animais , Antineoplásicos/farmacologia , Artemia , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Comportamento Alimentar/efeitos dos fármacos , Peixes , Homosteroides/farmacologia , Homosteroides/toxicidade , Humanos , Dose Letal Mediana , Espectrometria de Massas , Espectrofotometria Ultravioleta , Paladar/efeitos dos fármacos , Terpenos/farmacologia , Terpenos/toxicidadeRESUMO
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.