Biomedical subjects

J Camps

Publications and source records attributed to J Camps.

At least 19 recordsLinked to original sources

PubMed2006

Cytotoxicity of Epiphany and Resilon with a root model.

AIM: To record the cytotoxicity of Resilon and Epiphany (Pentron clinical technologies, Wallingford, CT, USA) using a root model. METHODOLOGY: Thirty teeth with single roots were sectioned at the enamel-cementum junction, the root canals prepared and each root then sterilized before filling with the lateral condensation technique using one of three filling materials (n = 10 per group): Resilon and Epiphany, Sealite (Septodont, Pierre Rolland, Merignac, France) and gutta-percha, Roekoseal Automix (Coltène/Whaledent, Langenau, Germany) and gutta-percha. The roots were stored at 37 degrees C in an incubator to allow for setting of the root filling materials. The apices of the roots were dipped in 1 mL of MEM culture medium for 1, 2, 7 and 30 days renewing the medium every day. After 24 h contact between the medium and the filled roots, the medium was used to measure the cytotoxicity on mouse fibroblasts L 929 with the MTT assay that recorded the mitochondrial activity of the target cells. An additional test according to ISO 10993-5 standards was undertaken to compare Resilon and Epiphany. RESULTS: The root model showed no statistically significant differences between the sealers at 7 and 30 days (NS). Epiphany and Resilon were the most cytotoxic materials at 1 and 2 days (P < 0.001). Unlike Epiphany, Resilon was not cytotoxic when tested according to ISO 10993-5 standards. CONCLUSIONS: The cytotoxicity of Resilon + Epiphany, due mainly to Epiphany, decreased after 2 days to reach a level comparable with commonly used root canal sealers.

Analysis of Variance↗

PubMed2005

[Multiple enterolithiasis, coexisting with bladder and gallbladder lithiasis, associated with colon adenocarcinoma].

Enteroliths are calculi primarily formed in the intestine. Enterolithiasis is a rare condition frequently associated with intestinal stasis. Usually it causes no symptoms in most cases, but it can be an important diagnostic clue in patients presenting intestinal occlusive symptoms. We report a case of multiple enterolithiasis, very infrequent pathology, coexisting with bladder and gall bladder lithiasis in a patient with colon adenocarcinoma. Diagnosis was made by X-rays and CT images. Calculi were analysed by several methods: chemical, infrared spectroscopy, stereoscopic microscopy and atomic emission spectroscopy; they showed that caluli are made up of organic material and whilokita (calcium and magnesium ortophosphate). No risk factors for lithogenesis were found in this patient excluding the intestinal stasis caused by intestinal narrowing as a result of adenocarcinoma. Genetic factors are suggested as main contributors to hyperlithogenesis observed in this patient. The physiopathological conditions were studied in depth and literature about this subject reviewed.

Abdominal Pain↗

PubMed2004

Influence of the powder/liquid ratio on the properties of zinc oxide-eugenol-based root canal sealers.

OBJECTIVE: The purpose of this study was to investigate the effects of modifications of the powder/liquid ratio by endodontists on the physical properties recommended by ISO standards as well as on other clinically relevant properties of zinc oxide-eugenol-based root canal sealers. METHODS: The powder/liquid ratio of two zinc oxide-eugenol-based root canal sealers (Cortisomol and Pulp Canal Sealer EWT) was recorded by 10 endodontists. The materials, prepared according to the different consistencies, were tested according to ISO standards to evaluate their physical properties. Their sealing efficiency and the release of eugenol were also evaluated on 20 single rooted teeth. RESULTS: Some results varied according to the material. Nevertheless, for both cements, an increased powder/liquid ratio led to a decreased flow, an increased radiopacity and a decreased amount of eugenol released. The variations in the powder/liquid ratio did not influence the dimensional changes and the apical leakage of both cements. SIGNIFICANCE: Variations in the powder/liquid ratio of zinc oxide-eugenol-based root canal sealers have a limited influence on the properties of the sealers. The endodontists can prepare the zinc oxide-eugenol-based root canal sealers at their chosen consistency according to the filling technique they use.

Analysis of Variance↗

PubMed2002

Cytotoxicity of orthodontic bands, brackets and archwires in vitro.

OBJECTIVES: In orthodontic therapy, different materials are used and subjected to a damp oral environment, which can modify their properties. In order to evaluate the biocompatibility of metallic and non-metallic orthodontic appliances their in vitro cytotoxicity has been measured. METHODS: Twenty-eight new and nine clinically used materials, including brackets, molar bands and archwires were used. The metallic materials were made of stainless steel, gold-plated steel, pure titanium, nickel-titanium, titanium-molybdenum and silver-based soldering alloy. The non-metallic materials were in polycarbonates and ceramics. After a release period of the material in the culture medium (0.1 mg/ml) for 3 and 14 days, the viability of fibroblasts L929 cultivated with this medium was compared to negative control with MTT assay. RESULTS: The results showed the non-cytotoxicity of the materials. The metallic and non-metallic materials were similar in terms of cytotoxicity. The cytotoxicity of clinically used samples was equivalent to that of the same non-used samples, except a cytotoxic sample, at 14 days, corresponding to a soldered and clinically used molar band. The 3 day results were different from the 14 day results in six cases out of 37. SIGNIFICANCE: In spite of the presence of one cytotoxic sample, the orthodontic materials can be considered as non cytotoxic. However, the practitioner should pay attention to the composition and the polish of soldering silver-based alloys containing copper and zinc in order to limit cytotoxic ion release. The cytotoxicity of the used sample related to ion release might be related to some clinical sub-acute effects related with orthodontic materials, thus a long term release period may be suitable to evaluate in vitro the sub-acute clinical effects of alloys.

Analysis of Variance↗

PubMed2002

Two- versus three-dimensional in vitro differentiation of human pulp cells into odontoblastic cells.

The spatial organization of the pulp cells may modify the cytodifferentiation process. The purpose of this study was to compare the two- versus three-dimensional cell culture systems for differentiation of human odontoblastic cells in vitro. Pulpal cores from freshly extracted human third molars were cultured in vitro in a perfusion device on two types of membranes: polyester membrane (two-dimensional [2D] cell culture) and nylon mesh (three-dimensional [3D] cell culture). The cells were incubated with minimum essential medium containing (a) substitute serum, (b) 10% fetal calf serum (FCS), (c) 10% fetal calf serum + 2 mM beta-glycerophosphate (beta GP), and (d) 10% fetal calf serum + transforming growth factor (TGF) beta 1. Immunohistochemistry was used to evaluate the expression of collagen I, osteonectin, and nestin. Small differences were observed between 2D and 3D cell culture systems. This was particularly evident in the 10% FCS group. beta-Glycerophosphate in the 3D system seems to stimulate the osteogenic cell phenotype, as a considerable induction of osteonectin is observed.

Adolescent↗

PubMed2001

Effects of high-fat, low-cholesterol diets on hepatic lipid peroxidation and antioxidants in apolipoprotein E-deficient mice.

The present study describes the effects of several high-fat low-cholesterol antiatherogenic diets on the hepatic lipid peroxidation and hepatic antioxidant systems in apolipoprotein E-deficient mice. Eighty mice were distributed into five groups and fed with regular mouse chow or chow supplemented with coconut, palm, olive and sunflower seed oils. After ten weeks, they were sacrificed and the livers were removed so that lipid peroxidation and alpha-tocopherol concentrations, and superoxide dismutase, glutathione peroxidase and glutathione reductase activities could be measured. The size of the atherosclerotic lesions in the aortas was also measured. Results showed that the diets supplemented with olive oil, palm oil or sunflower seed oil significantly decreased the size of the lesion. However, there was an association between those mice that were on diets supplemented with palm or coconut oils and a significant increase in hepatic lipid peroxidation. This association was not found in animals fed with olive or sunflower seed oils, the diets with the highest content of vitamin E. The dietary content of vitamin E was significantly correlated (r = 0.98; p < 0.05) with the hepatic concentration of this compound. Our study suggests that the high content of vitamin E in olive oil or sunflower seed oil may protect from the undesirable hepatotoxic effects of high-fat diets in apo E-deficient mice and that this should be taken into account when these diets are used to prevent atherosclerosis.

Animals↗

PubMed2001

Supplementation with vitamin E and/or zinc does not attenuate atherosclerosis in apolipoprotein E-deficient mice fed a high-fat, high-cholesterol diet.

Ever since oxidation has been known to be involved in atherogenesis, antioxidants have received considerable attention as potential antiatherogenic agents. The lipid-soluble vitamin E is the main antioxidant carried by lipoproteins. Zinc is a water-soluble trace element that acts as a cofactor of superoxide dismutase (SOD) and has an antioxidant role in several oxidative processes. To test the hypothesis that zinc could adjuvate the antioxidant activity of vitamin E and diminish atherogenesis, we explored how supplementing diet with vitamin E and/or zinc would affect an atherosclerosis-prone animal like Apo E-deficient mice. The increased plasma concentrations of both vitamin E and zinc showed that absorption was high. They had a significant hypolipidemic effect and the supplemented animals had 25% less plasma cholesterol and triglyceride than controls. The SOD activity was significantly higher in washed erythrocytes from mice supplemented with zinc. The plasma of supplemented animals was also significantly more resistant to oxidation. The size of lesions in the proximal aortic region did not differ among groups. Therefore, dietary supplementation resulted in the expected antioxidant effects but there was no substantial attenuation of atherosclerosis in this particular model.

Animals↗

PubMed2001

The antioxidant and hepatoprotective effects of zinc are related to hepatic cytochrome P450 depression and metallothionein induction in rats with experimental cirrhosis.

The aim of the present study was to investigate the time-course of changes in hepatic lipid peroxidation, cytochrome P450 and metallothionein concentrations, and superoxide dismutase and catalase activities in relation to the onset and development of cirrhosis in CCl4-treated rats. Further, the effects of oral zinc administration on these parameters were assessed. Cirrhosis was induced in 120 rats by intraperitoneal injections of CCl4 twice weekly over 9 weeks. Controls were 120 additional animals. Both groups were further subdivided to receive either a standard diet or one supplemented with zinc. Subsets of 10 animals each were euthanized at weeks 1, 2, 3, 5, 7 and 9 from the start of the study. Results indicated that zinc administration delayed the cirrhotic process and the increase in lipid peroxidation. These changes, consistently maintained during the first 5 weeks of the study, were associated with a significant decrease in the hepatic concentration of cytochrome P450 and an increase in the hepatic concentration of metallothioneins. Zinc supplementation did not produce any significant change in superoxide dismutase and catalase activities. These results suggest that cytochrome P450 and metallothioneins may play an important role in the hepato-protective effects of zinc against lipid peroxidation in experimental cirrhosis.

Administration, Oral↗

PubMed2001

In vivo diagnostic assessment of dentinal caries by junior and senior students using red acid dye.

The aim of this study was firstly to determine and compare the ability of inexperienced junior dental students (Fourth-year) and senior students (Fifth-year) versus a dental school instructor to identify demineralized dentine with the aid of a caries-disclosing solution and secondly to evaluate an eventual improvement of the caries diagnosis accuracy of junior (Fourth-year) and senior (Fifth-year) dental students. Three successive stages were used to check the ability of the dental students to diagnose and excavate the de-mineralized dentine. This study pointed out that 96% of junior dental students versus a teacher failed to remove all of the demineralized dentine without the use of a caries detector at the first stage and 79% at the second stage in the same condition. 100% of senior students versus a teacher, also failed to diagnose dental caries without a caries detector, but only at the first stage. However, at the second stage, unlike the junior students, all of the senior students were able to remove all of the demineralized dentine. Without the use of a caries detector dye, the risks of the dental students leaving demineralized dentine are high. This technique may be particularly helpful for the fourth-year students who are performing their first restorative treatment.

Anesthesia, Dental↗

PubMed2001

Hepatic paraoxonase activity alterations and free radical production in rats with experimental cirrhosis.

Relationships between hepatic antioxidant paraoxonase (PON1) activity, lipid peroxidation, and liver injury were investigated in rats with CCl(4)-induced cirrhosis. The study was performed in 60 CCl(4)-treated rats and 60 control animals receiving a standard diet or one supplemented with zinc. Subsets of 10 animals each were killed at weeks 1, 5, and 7 of the study. Results showed that PON1 significantly decreased in rats given CCl(4) alone compared with control animals. This effect was partially reversed in animals receiving zinc. Conversely, lipid peroxides were significantly increased in rats given CCl(4) alone and returned to approximately normal values in animals receiving zinc supplement. PON1 was inversely correlated with lipid peroxidation in all the animals studied. These alterations coincided with changes in serum alanine aminotransferase activity. In vitro incubation of isolated microsomes with CCl(4) or malondialdehyde did not produce any significant changes in PON1, indicating that the decrease in PON1 in CCl(4)-treated animals was not secondary to a direct inhibitory effect of lipid peroxidation products. These data show a time course and quantitative relationship between PON1 activity and lipid peroxidation in rats with CCl(4)-induced cirrhosis and suggest that this enzyme plays a significant role within the antioxidant systems in liver microsomes.

Alanine Transaminase↗

PubMed2001

Effects of pressure and measurement time on the fluid filtration method in endodontics.

The purpose of this study was to evaluate the influence of the measurement time and the pressure on the outcome of a fluid filtration test. Thirty-six roots were prepared with a Profile device and filled with Thermafil. The leakage along the filling material was recorded under a 15 cm H2O pressure (n = 18) or a 150 cm H2O pressure (n = 18) at 3 min, 1 h, and 24 h. The fluid flow expressed as microl min(-1) decreased with an increased measurement time (p = 0.001) and was higher in the high pressure group (p = 0.001). The fluid flow of this study, where all of the teeth were filled with the same technique, ranged from 3.8 x 10(-5) microl min(-1) cm H2O(-1) to 43 x 10(-5) microl min(-1) cm H2O(-1), depending on the pressure and measurement time. This shows the need for standardization to compare the results from various studies.

Analysis of Variance↗

PubMed2001

Lack of correlation among three methods for evaluation of apical leakage.

The purpose of this study was to compare three methods of evaluation of the apical seal. Thirty-six teeth were prepared with a ProFile device and filled according to three filling methods: Thermafil (n = 12), warm vertical condensation (n = 12), and the single cone technique (n = 2). The apical seal was recorded with three methods, each successively used on the same teeth: a fluid filtration method, an electrochemical method, and a dye penetration study. The three methods of evaluation did not rank the apical leakage of the three filling techniques in the same order. The fluid filtration method showed that the vertical condensation was superior to Thermafil, which was in turn superior to the single cone technique (p = 0.04). The dye penetration study showed that the Thermafil was a better technique than the vertical condensation and the single cone technique (p = 0.005). The electrochemical method showed no statistical difference among the three filling techniques. No correlation was found among the results obtained with the three methods of evaluation. This study shows that several studies are necessary before comparing the apical seal obtained with various filling techniques.

Analysis of Variance↗

PubMed2001

In vitro apical leakage of system B compared with other filling techniques.

A fluid filtration system was used to compare the apical microleakage of roots filled with the system B (Analytic Technology), single-cone technique, lateral condensation, vertical condensation, and Thermafil (Caulk-Dentsply). After preparation of the canal system with a Profile (Caulk-Dentsply) five groups of 10 single-rooted teeth were randomly filled according to 1 of the 5 techniques. Phosphate-buffered saline was forced under a 15 cm H2O pressure, through the apex, toward the coronal part of the root. The filtration rate in L s(-1) Kpa(-1) was recorded 24 h after filling and after 1-month storage in phosphate-buffered saline. The 24 h results showed that the single cone technique provided the highest leakage (p = 0.001). At 1-month system B, Thermafil and vertical condensation had less leakage than the two other techniques (p = 0.0001): lateral condensation produced moderate apical leakage, whereas the single cone technique showed the highest leakage. Regardless of the technique the apical leakage increased after 1-month storage (p = 0.001 or p = 0.0001, depending on the technique).

Analysis of Variance↗

PubMed2001

Instability of lipoprotein(a) in plasma stored at -70 degrees C: effects of concentration, apolipoprotein(a) genotype, and donor cardiovascular disease.

BACKGROUND: There is considerable evidence to suggest that plasma lipoprotein(a) [Lp(a)] concentration is a cardiovascular risk factor. Confusing results in epidemiologic studies, however, suggest that the effects of storage should be further investigated. The influence of the assay method, the initial plasma Lp(a) concentration, and the apolipoprotein(a) [apo(a)] genotype are all factors that should be considered. METHODS: Blood was obtained from 65 survivors of premature myocardial infarction and 95 age-matched controls. The plasma samples were stored in sterile conditions at -70 degrees C for 5 years in the presence of antioxidant and antiproteolytic substances. Plasma Lp(a) was measured by immunoturbidimetry, and apo(a) alleles were determined by pulsed-field gel electrophoresis and Southern blotting. RESULTS: Plasma Lp(a) was significantly higher in patients. The mean kringle number for the smallest isoform was also lower in patients than in controls, but no differences were found in the distribution of the largest isoform. All patients and controls were heterozygotes. During storage, mean Lp(a) decreased significantly in samples from patients (-23%; P <0.001) but not in samples from controls (-9%; P, not significant). This was not related to the kringle number and was limited to samples with initial plasma Lp(a) concentrations between 41 and 345 mg/L. CONCLUSIONS: Plasma Lp(a) from patients is less stable than Lp(a) from controls, and the difference is not related to distribution of apo(a) genotypes but may be concentration-dependent. Differential sample stability may complicate the interpretation of several studies.

Adult↗

PubMed2000

The continuous administration of aspirin attenuates atherosclerosis in apolipoprotein E-deficient mice.

Aspirin reduces the incidence of thrombotic occlusive events. Classically this has been thought to be due to the platelet inhibitory action of aspirin but it has recently been shown that inflammation plays a predominant role in the initiation and progression of lesions in atherosclerosis. In humans, treatment with aspirin reduces cardiovascular risk and slows carotid plaque growth in a dose-dependent fashion. We have explored this issue in Apo E-deficient mice on a high-fat, high cholesterol diet which provided these animals with a continuous administration of 500 microg/day of acetylsalicylic acid in the drinking water. After 10 weeks of treatment, the size of the atherosclerotic lesion at the aortic sinus had reduced by 35%. At the end of the trial there were no significant changes in either plasma lipids or in the quantitative distribution among lipoproteins. Likewise, the total antioxidant status and the resistance of plasma to oxidation in vitro was similar and there was no change in the distribution of iron deposits and in the relative composition of plasma pro-oxidants and antioxidants, or in the concentration of plasma in ferritin. Therefore, it is our hypothesis that the antiinflammatory effect is responsible for the reduction in lesion size. We propose that antiinflammatory molecules which do not cause gastrointestinal complications should be tested in humans to determine long-term efficacy in the attenuation of atherosclerosis.

Animals↗

PubMed2000

Human dentin production in vitro.

The main hard tissues of teeth are composed of dentin and enamel, synthesized by the mesenchyme-derived odontoblasts and the epithelial-derived ameloblasts, respectively. Odontoblasts are highly differentiated post-mitotic cells secreting the organic matrix of dentin throughout the life of the animal. Pathological conditions such as carious lesions and dental injuries are often lethal to the odontoblasts, which are then replaced by other pulp cells. These cells are able to differentiate into odontoblast-like cells and produce a reparative dentin. In this study we reproduced this physiological event in an in vitro culture system using pulps of human third molars. Pulp cells cultured in presence of beta-glycerophosphate formed mineralization nodules, which grew all over the culture period. The immunohistochemical study revealed that, as odontoblasts, pulp cells contributing to the nodule formation express type I collagen, osteonectin, and nestin. By the exception of nestin, these proteins are also detected in the nodules. The composition of the nodules was also analyzed by Fourier transform infrared microspectroscopy. The spectra obtained showed that both the organic and the mineral composition of the nodules have the characteristics of the human dentin and differ from those of enamel and bone. Taken together, these results show that both the molecular and the mineral characteristics of the human dentin matrix are respected in the in vitro culture conditions.

Adolescent↗

PubMed2000

Determinants of plasma homocyst(e)ine in patients with nephrotic syndrome.

Hyperhomocyst(e)inemia is an independent risk factor for atherothrombosis in several clinical settings in which renal function is impaired, but its prevalence in the nephrotic syndrome has not been investigated in detail, even though this syndrome provides an excellent model in which to study a possible link between albuminuria, proteinuria, and hyperhomocyst(e)inemia. We obtained plasma and urine from 27 patients with biopsy-confirmed membranous glomerulonephritis presenting nephrotic syndrome and 27 matched controls and determined the concentrations of homocyst(e)ine and proteins considered putative markers of glomerular and tubular function. Hyperhomocyst(e)inemia, defined as the mean +SD of the plasma homocyst(e)ine concentration of the controls [plasma homocyst(e)ine concentration >10.8 micromol/l] was present in 26% of the patients with nephrotic syndrome but in only 7.4% of the controls. Furthermore, the degree of hyperhomocyst(e)inemia was more severe in the nephrotic patients than in the controls. The existence of renal failure, tubular damage, and, interestingly, relatively well conserved glomerular function barrier were the main predictors of increased levels of plasma homocyst(e)ine. In conclusion, hyperhomocyst(e)inemia is a frequent cardiovascular risk factor present in patients with nephrotic syndrome and renal failure, but it is not directly associated with proteinuria.

Adult↗

PubMed2000

Evaluation of a particle-enhanced turbidimetric immunoassay for the measurement of ferritin: application to patients participating in an autologous blood transfusion program.

OBJECTIVES: To evaluate a turbidimetric immunoassay for the measurement of ferritin, and to assay this method in a group of patients undergoing an autologous blood transfusion program. DESIGN AND METHODS: We used an ILab 900 analyzer. This instrument automates a particle-enhanced immunoturbidimetric assay with an analysis time of 9 min. This technique was compared with a microparticle immunoassay. The turbidimetric assay was used to measure ferritin in a group of 30 patients undergoing an autologous blood transfusion program. RESULTS: The assay was linear in the range 3-1400 microg/L (r = 0.9999). The intra- and inter-assay imprecision (CV) at 20, 97 and 469 microg/L were <3.0 and <5.0%, respectively. Recovery was 88. 7 to 97.4%. The detection limit was 3 microg/L. Hemoglobin (</=4 g/L), mild hyperbilirubilinemia (bilirubin </=50 micromol/L), triglycerides (</=10 mmol/L) and myeloma paraproteins did not interfere with the assay. The assay showed good correlation with a microparticle enzymoimmunoassay (r = 0.994) with a mean difference between methods of -6 +/- 16 microg/L. This method was sensitive, accurate, and fast enough for an efficient follow-up of autologous blood transfusion patients. CONCLUSIONS: The new automated serum assay for ferritin is an attractive alternative that avoids the need for dedicated instrumentation.

Adult↗