Homocyst(e)ine and the C677T mutation of methylenetetrahydrofolate reductase in survivors of premature myocardial infarction.
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Adult↗
Biomedical subjects
J Camps
Publications and source records attributed to J Camps.
Factors influencing pulpal response to cavity restorations.
OBJECTIVES: The purposes of this retrospective work were: (1) to determine the relative importance of bacteria on cavity walls, remaining dentin thickness and post-operative time on pulpal inflammation after cavity restoration; (2) to compare the respective influences of bacterial microleakage and the restorative material itself on pulp reaction severity. METHODS: 317 class V cavities, in human bicuspids scheduled for extraction for orthodontic reasons were used for this study. Nine different materials were included. The severity of the pulpal reaction was ranked on hematoxylin/eosin stained sections according to FDI standards. The further parameters recorded were: (1) the presence or absence of bacteria on the cavity walls was noted on Brown and Brenn stained sections; (2) the remaining dentin thickness was measured and the teeth classified into three groups (< 500, 500-1000, > 1000 microns); and (3) the post-operative delay before extraction was recorded and classified as short time (< 5 weeks) or long time (> 5 weeks). Three two-way analyses of variance (ANOVA) followed by Kruskall and Wallis tests evaluated the influence of the three parameters on pulpal reaction severity. The third ANOVA also compared pulpal reactions under the different materials when the teeth were pooled, on bacteria free teeth and on bacteria contaminated teeth. RESULTS: The first ANOVA ranked by decreasing order of importance: the presence of bacteria (p < 0.0001), the remaining dentin thickness (p = 0.02) and the post-operative delay (p = 0.04). The second ANOVA showed no difference among the restorative materials when bacteria were present on the cavity walls. SIGNIFICANCE: The presence of bacteria on the cavity walls is the main factor influencing pulpal reaction under restorative materials, but does not account for 100% of the cases.
Adolescent↗
Time-course of changes in hepatic lipid peroxidation and glutathione metabolism in rats with carbon tetrachloride-induced cirrhosis.
1. The aims of the present study were to assess: (i) the temporal relationships between hepatic lipid peroxidation, changes in the glutathione detoxification system and the onset/development of cirrhosis in CCl4-treated rats; and (ii) the effects of oral zinc administration on these parameters. 2. Cirrhosis was induced in 120 rats by intraperitoneal injections of CCl4 twice a week over 9 weeks. One hundred and twenty additional animals were used as controls. Both groups were further subdivided to receive either a standard diet or one supplemented with zinc. Subsets of 10 animals each were killed at weeks 1, 2, 3, 5, 7 and 9 from the start of the study. 3. Induction of cirrhosis produced a decrease in the components of the hepatic glutathione anti-oxidant system: glutathione transferase activity decreased from week 1, the concentration of reduced glutathione (GSH) decreased from week 5 and glutathione peroxidase (GPx) activity decreased from week 7. This impairment was chronologically related to an increase in free radical generation. Hepatic lipid peroxidation was significantly correlated with GPx activity (r = -0.47; P < 0.001) in CCl4-treated rats. Zinc administration did not produce any significant improvement of the hepatic glutathione system. 4. In conclusion, cirrhosis induction in rats by CCl4 administration produced a decrease in the hepatic glutathione antioxidant system that was related to an increase in free radical production. Furthermore, zinc supplementation produced a reduction in the degree of hepatic injury and a normalization of lipid peroxidation, but not an improvement of the hepatic GSH anti-oxidant system.
Animals↗
Agreement study of methods based on the elimination principle for the measurement of LDL- and HDL-cholesterol compared with ultracentrifugation in patients with liver cirrhosis.
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Cholesterol, HDL↗
Buffering action of human dentin in vitro.
PURPOSE: The purpose of this study was to determine the relative contributions of the mineral and organic phases of dentin to its total buffering capacity and to compare the buffering abilities of normal and caries-affected dentin for acids used in adhesive dentistry. MATERIALS AND METHODS: Disks of normal and caries-affected human coronal dentin 0.6 mm thick were prepared. Fifty microL of various acids were applied to the surface of mineralized or completely demineralized dentin for varying lengths of time. They were collected from the surface and combined with water rinses to permit titration of the total amount of acid applied, the amount recovered, the total amount that was taken up by the dentin, and the amount that diffused across dentin into 1 mL of water. Equal volumes of acids were applied to mineralized or demineralized dentin powder or hydroxyapatite powder. RESULTS: About 88% to 90% of applied acid was recovered from the surface; only 10% to 12% of the acid was taken up by dentin. Of the H+ that was taken up, only 1% to 2% actually diffused across 0.6 mm of dentin. Increasing the application time of 37% phosphoric acid did not increase the amount of H+ that diffused across dentin. Increasing the concentration of phosphoric acid from 10% to 65% produced only slight increases in H+ diffusion across dentin. There was no difference in the buffering capacity of normal vs caries-affected dentin disks. Almost all of the buffering capacity of dentin is due to its mineral phase. CONCLUSION: The high buffering capacity of dentin and the high reactivity of H+ insure that little H+ diffuses through dentin more than 0.6 mm thick.
Analysis of Variance↗
Laparoscopic repair of recurrent hernias.
BACKGROUND: Recurrence after primary conventional inguinal herniorrhaphy occurs in approximately 10% of patients depending on the type of repair and expertise of the surgeon. The repair of the resulting recurrent hernia is a daunting task because of already weakened tissues and obscured and distorted anatomy. The failure rate of these repairs using an open anterior approach may reach as high as 36%. Because of such a high failure rate, a number of investigators have focused on repairing these difficult recurrent hernias laparoscopically using a tension-free approach. Some of the earlier reports suggested a low recurrence rate of 0.5% to 5% when a laparoscopic approach was used to repair these hernias. The purpose of this study was to evaluate the efficacy of laparoscopic treatment for recurrent hernias in our institutions. METHODS: Between February 1991 and February 1995, 96 recurrent hernias were repaired in 85 patients (78 men and 7 women). There were 48 right, 26 left, and 11 bilateral hernias. The mean age of the patients was 59 years (range, 18-86 years); the mean height was 69 in. (range, 54-77 in.); and the mean weight was 176 pounds (range, 109-280 pounds). A total of 68 herniorrhaphies were performed using the transabdominal preperitoneal (TAPP) method: 19 using intraperitoneal on-lay mesh (IPOM) repair and 8 using the total extraperitoneal (TEP) method. The method of repair in one patient was not recorded. The mean operating time was 76 min (range, 47-172 min). Thirteen patients underwent additional procedures. RESULTS: Long-term follow-up was performed by questionnaire, examination, or both in 76 patients (85 hernias). Median follow-up time was 27 months (range, 2-56 months). There were four recurrences (2 in IPOM and 2 in TAPP). Three of these were repaired laparoscopically and one conventionally. There were 20 minor and 14 major complications and no mortality. One conversion occurred in the TAPP group. Mean postoperative stay was 1.4 days (range, 0-4 days). It was felt by 92% of the patients that their symptoms were completely relieved, whereas 4% of the patients continued to exhibit symptoms for which their hernia was repaired, and 3.6% failed to answer. As reported, 86% of the patients preferred their laparoscopic repair; 1% preferred the conventional repair; and 13% failed to reply. Afterward, 77% of the patients returned to normal activity, and 35% returned to vigorous activity within 4 weeks of surgery. Satisfaction with laparoscopic repair was expressed by 92% of the patients, whereas 8% either were dissatisfied or did not answer. In the end, 95% of the patients stated that they would recommend laparoscopic hernia surgery to their family and friends. CONCLUSIONS: These preliminary data show that laparoscopic repair of recurrent inguinal hernia is a safe alternative procedure with acceptable rates of recurrence and complications.
Adult↗
In vitro cytotoxicity of one-step dentin bonding systems.
The cytotoxicity of resinous monomers may vary on mixing, calling into question the cytotoxicity of the new dentin bonding agents that are mixed in a single vial. The cytotoxicity of fourth and fifth generation dentin bonding agents was compared in vitro. All-Bond 2, One-Step, Scotchbond Multi-Purpose, Scotchbond One, Syntac, Syntac Single Component, Tenure, and Tenure Quick were tested uncured. The cytotoxicity of several dilutions of fourth generation dentin primer, dentin bonding agent, dentin primer + dentin bonding agent, and fifth generation single component products diluted at 10(-1) to 10(-8) in culture medium was recorded with a MTT assay on L929 fibroblasts. Only one synergistic (increased cytotoxicity after mixing primer and bonding agent) cytotoxic effect was observed with Tenure at 10(-5) dilution. An antagonistic effect (decreased cytotoxicity after mixing primer and bonding agent) was observed with All-Bond 2 between 10(-4) and 10(-8) dilutions. Scotchbond and Syntac fifth generation dentin bonding agents were less cytotoxic than their fourth generation counterparts. All-Bond and Tenure fifth generation dentin bonding agents were more cytotoxic than their fourth generation counterparts only in low dilutions. Clinical studies should confirm these good results, because no dramatic synergistic cytotoxic effect could be detected.
Analysis of Variance↗
Concentration of eugenol apically released from zinc oxide-eugenol-based sealers.
This study investigated the amount of eugenol released from a zinc oxide-eugenol-based sealer at the apex of teeth filled according to two techniques: the single-cone and the Thermafil. The crown of 10 maxillary central incisors was removed, and the canal was prepared with ProFile to a size 30 under NaOCl irrigation. The patency of the apex was checked with a #8 K-file between each ProFile. Five roots were filled with a Thermafil #30 and 0.03 g of Sealite; five roots were filled using a Lentulo with 0.07 g of sealer and a gutta-percha cone #30. The powder/liquid ratio of the sealer was of 5/1. The concentration of eugenol released in phosphate-buffered saline was spectrofluorimetrically determined immediately after sealing, after 1 day, and after 1 month of storage. The roots filled with the single-cone technique released significantly more eugenol than these filled with Thermafil immediately after sealing (p = 0.002); but, after 1-day or 1-month storage, there was no difference. For both techniques, eugenol concentration decreased over time (p = 0.01): the immediate concentration was higher than the 1-day concentration (p = 0.04). Eugenol concentration after 1-month storage was undetectable. The results of this work show that the level of eugenol released from a zinc oxide-eugenol-based sealer beyond the apex is very low and decreases over time.
Eugenol↗
Comparison of two implantation sites for testing intraosseous biocompatibility.
The purpose of this study was to compare two implantation sites--the mandible and the femur of the rabbit--for testing in vivo intraosseous biocompatility. Twenty-two new Zealand rabbits were anesthetized, and the mandibular and femur bones were exposed. A hybrid glass ionomer cement or zinc oxide eugenol cement was loaded into silicone carriers and inserted into the two bones after drilling the two cortical plates. Eleven rabbits were killed 4 wk after implantation, and 11 rabbits were killed after 12 wk. The mandibles and femurs were prepared using standard histological procedures; tissue reactions were graded from none to severe. At 4 wk, no statistically significant difference was found between the two implantation sites. After 12 weeks, bone healing was statistically better in the mandible than in the femur. The mandible seems to be a better implantation site in the case of intraosseous implantation tests. The intraosseous biocompatibility of Vitremer was similar at 4 wk and superior at 12 wk to that of Super-EBA.
Animals↗
Inhibition of hepatic cell nuclear DNA fragmentation by zinc in carbon tetrachloride-treated rats.
BACKGROUND/AIMS: The aims of this study were to ascertain: 1) whether hepatic cell DNA fragmentation is increased in rats with early stages of liver disease induced by carbon tetrachloride; 2) whether the inhibition of DNA cleavage is involved in the hepatoprotective effects of zinc; and 3) if relationships exist between DNA fragmentation and the onset of fibrosis in this experimental model. METHODS: Twenty-one treated rats and 23 controls were divided into two groups to receive either a standard diet or one supplemented with zinc. All the animals were sacrificed 1 week later for histological and biochemical assessments, which included a DNA fragmentation index, hepatic zinc and metallothionein concentrations, fibrosis measured by hepatic hydroxyproline concentration and plasma alanine aminotransferase activity. RESULTS: Hepatic cell DNA fragmentation was increased in rats with early hepatic fibrosis and the increase was independent of hepatocytolysis, as measured by alanine aminotransferase activity. Oral zinc administration inhibited hepatic cell DNA fragmentation in the treated rats and was proportional to the hepatic concentration of the metal. The mechanism of the zinc-mediated decrease in DNA cleavage was related to an increase in the hepatic metallothionein concentration. Hepatic cell DNA fragmentation was related to hydroxyproline concentration. CONCLUSIONS: Our results suggest that apoptosis may be involved in the early transformations occurring in the liver and which can lead to the initiation of cirrhosis. As such, the potential therapeutic use of zinc supplementation would warrant further investigation.
Animals↗
Hepatic production of apolar aldehydes in rats with carbon tetrachloride-induced cirrhosis.
The aim of this study was to identify apolar aldehydes in liver homogenates from rats with CCl4-induced cirrhosis and, as a corollary, the antioxidant effect of zinc administration. The study was performed in five control rats and in ten cirrhotic rats which were further sub-divided into two groups to receive either a standard diet or one supplemented with zinc. The percentage of hepatic fibrosis, plasma malondialdehyde concentration and alanine aminotransferase activity were measured as well as the following aldehydes: hexanal, octanal, decanal, 2-hexenal, 2-octenal, 2-nonenal, 2,4-heptadienal and 2,4-decadienal. Of the 10 cirrhotic rats, 4 had elevated concentrations of the highly toxic 2,4-dialkenals which coincided with a higher percentage of fibrosis and plasma alanine aminotransferase activity. These aldehydes were not observed in the control group. Zinc administration was associated with a reduction of the hepatic malondialdehyde concentration and an amelioration on the degree of hepatic injury. In conclusion, this study demonstrates the presence of the highly toxic 2,4-dialkenals in hepatic tissue of rats whith CCl4-induced cirrhosis. Results obtained would suggest that these particular aldehydes may be related to the severity of the hepatic injury.
Aldehydes↗
Altered composition of lipoproteins in liver cirrhosis compromises three homogeneous methods for HDL-cholesterol.
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Cholesterol, HDL↗
Evaluation of a particle-enhanced turbidimetric immunoassay for the measurement of immunoglobulin E in an ILab 900 analyzer.
BACKGROUND: The measurement of immunoglobulin E (IgE) in serum is widely used in the diagnosis of allergic reactions and parasitic infections. We describe here a fully automated assay for human IgE suitable for routine application in a general chemistry analyzer. METHODS: We used an ILab 900 analyzer. This instrument automates a particle-enhanced immunoturbidimetric assay with an analysis time of 9 min. RESULTS: The assay was linear in the range 4-1000 kIU/L (r = 0.9998). The intra- and interassay CVs at 57, 235, and 434 kIU/L were <3.5% and <7.4%, respectively. The detection limit was 4 kIU/L. Hemoglobin (</=16 g/L), bilirubin (</=250 micromol/L), and myeloma paraproteins did not interfere with the assay. The assay showed good correlation with a microparticle enzyme immunoassay (r = 0.998) with a mean difference between methods of -6 +/- 26 kIU/L. CONCLUSION: The new automated serum assay for IgE is an attractive alternative that avoids the need for dedicated instrumentation.
Autoanalysis↗
Lipoprotein(a) and the significance of the association between platelet glycoprotein IIIa polymorphisms and the risk of premature myocardial infarction.
Platelet glycoprotein IIb/IIIa may be involved in the pathogenesis of myocardial infarction as the key element in platelet aggregation and as the binding site of lipoprotein(a) to platelets, inhibiting plasminogen binding and activation. Recently, a strong association between the P1A2 polymorphism of the glycoprotein IIIa gene and acute coronary thrombosis has been reported. although this has not been confirmed. In an associated study, we determined plasma lipoprotein levels, the apo E genotype and the P1A genotype in 250 males under 55 years with myocardial infarction and they were compared with 250 age- and sex-matched controls. Patients showed an over-representation of the epsilon3/4 genotype with respect to the control group. We found that there were no differences in the allelic frequency of P1A2 between case patients and age-matched controls (chi2 = 0.05, P = 0.92) and that subjects bearing the P1A2 allele showed higher plasma lipoprotein(a) concentration than p1A1/P1A1 individuals. Therefore, in this population there is no association between carriage of p1A2 allele and increased risk of myocardial infarction but the carriage of P1A2 is associated with higher plasma Lp(a) concentration.
Adult↗
Eugenol diffusion through dentin related to dentin hydraulic conductance.
OBJECTIVES: The purpose of this study was (1) to find an easy way of evaluating the concentration of eugenol in cell culture fluids; (2) to confirm the relationship between the concentration and the cytotoxicity of eugenol in vitro; (3) to evaluate the cytotoxicity of four temporary eugenol-based filling materials: IRM, super EBA, Kalsogen and zinc oxide-eugenol cement; and (4) to establish a relationship between dentin permeability, eugenol diffusion and cytotoxicity. METHODS: (1) The concentration of eugenol was measured with a spectrofluorimeter; (2) the cell viability of L 929 cells cultivated for 24 h with eugenol-containing medium was evaluated by the MTT assay; (3) after measurement of hydraulic conductance, occlusal cavities in human teeth in vitro were filled with the restorative materials. The cytotoxicity was measured with undiluted test medium and with various dilutions in culture medium; (4) after Lp measurement, the eugenol concentration in the media in the pulp chamber that diffused from IRM and 10(3) mol/l eugenol solution was measured. RESULTS: (1) A proportional relationship (p = 0.001 and r = 1) was found between the concentration of eugenol; (2) eugenol started to be cytotoxic at 10(-5) mol/l and killed 95% of the cells at 10(-3) mol/l; (3) zinc oxide-eugenol cement was the most cytotoxic filling material when tested with the 1:100 dilution; (4) a significant relationship was found between Lp and cytotoxicity (p = 0.04) depending on the dilution of the test medium. A significant relationship was found between Lp and eugenol diffusion from a 10(-3) mol/l solution (p = 0.03) but not between Lp and eugenol diffusing from solid IRM (non significant). SIGNIFICANCE: Eugenol diffusion from zinc oxide-eugenol cement appears to depend more on the role of hydrolysis of eugenol from zinc oxide-eugenol cement than on dentin permeability.
Analysis of Variance↗
Sealing ability of super EBA and Dyract as root-end fillings: a study in vitro.
The purpose of this study was to compare, in vitro, the sealing ability of Super EBA and a compomer, Dyract, as root-end filling materials. Forty-eight single-rooted human teeth were cleaned, shaped and obturated with gutta-percha. The root apices were resected and root-end cavities were prepared. Twenty teeth were retrofilled with Super EBA and Dyract; eight teeth served as positive and negative controls. Half of the teeth in each group were immersed in basic fuschin for 4 weeks, the other half for 12 weeks. The teeth were then embedded in resin, sectioned, and the maximum extent of dye penetration measured. Statistical analysis (ANOVA) did not reveal a significant difference between the two materials at 4 weeks. At 12 weeks, the extent of dye penetration was statistically significant with Super EBA leaking more than Dyract (P = 0.002). Moreover, the extent of the dye penetration was statistically significantly different for Super EBA between the 4- and 12-week groups (P = 0), whereas no such difference was found for Dyract. Thus, the sealing ability of Dyract was found to be better than Super EBA at 12 weeks.
Compomers↗
Effects of desensitizing agents on human dentin permeability.
PURPOSE: To compare the in vitro effects of three desensitizing agents on hydraulic conductance of human dentin: Protect (n = 10), Gluma Desensitizer (n = 10), MS Coat (n = 10) (Pain-Free in the USA). MATERIALS AND METHODS: Dentin discs were prepared from 40 freshly extracted normal human third molars. The pulpal side of the dentin discs was etched with 37% phosphoric acid for 15 s and then rinsed under tap water. The coronal side was sequentially ground and the dentin discs were sonicated for 30 min. The hydraulic conductance was measured filtering 20% serum in phosphate buffered saline under a pressure of 15 cm H2O. The hydraulic conductance of each dentin specimen was measured before using the desensitizing agent and this value was designated as 100%. Thirty dentin discs were treated, the hydraulic conductance was remeasured and expressed as a percentage of the hydraulic conductance of that specimen before treatment. The teeth were stored for 1 month at 37 degrees C in deionized water and the hydraulic conductance of the 40 dentin discs was recorded again. Ten dentin discs were left untreated to serve as a control. RESULTS: No statistical difference was found between the immediate hydraulic conductance of the three groups after treatment. After 1-month storage, the control group showed a statistically higher hydraulic conductance than the three treated groups. There was no statistical difference between the three dentin desensitizing agents evaluated.
Acid Etching, Dental↗
Evaluation of a homogeneous assay for high-density lipoprotein cholesterol: limitations in patients with cardiovascular, renal, and hepatic disorders.
We evaluated the performance of a homogeneous assay for the automated measurement of high-density lipoprotein cholesterol (HDL-C) and compared it with a conventional precipitation technique in the following groups of people: control subjects (group A), clinically-healthy elderly (group B), myocardial infarction patients (group C), nephrotic syndrome patients (group D), and liver cirrhosis patients (group E). The performance of the technique was acceptable with respect to precision, accuracy, linearity, and detection limit. Triglycerides up to 40 mmol/L and bilirubin up to 150 micromol/L did not cause interferences. Hemoglobin decreased HDL-C measurements. Samples were stable at -20 degrees C for up to four months. Bland-Altman plots showed a good agreement between both techniques in the control group but with a progressive divergence in the patient groups B to E. Results indicate limitations of the technique in certain clinical conditions and, coincidentally, the need for reliable calibration materials.
Adult↗