Microbial diversity in persistent root canal infections investigated by checkerboard DNA-DNA hybridization.

INTRODUCTION: The aim of the present study was to investigate the composition of the root canal microbiota in endodontic failures in order to identify and quantify these microorganisms. METHODS: Microbiological samples were taken from 36 root canals with persistent endodontic infection. The presence, levels, and proportions of 79 bacterial species were determined by checkerboard DNA-DNA hybridization. The Pearson correlation coefficient was used to investigate the relations between bacterial counts and clinical conditions (P ≤ .05). RESULTS: Enterococcus faecium (36%), Streptococcus epidermidis (36%), Eubacterium saburreum (28%), Parvimonas micra (28%), Streptococcus sanguis (28%), Capnocytophaga sputigena (28%), Leptotrichia buccalis (28%), Enterococcus faecalis (28%), and Staphylococcus warneri (28%) were the most prevalent species; and there was a low prevalence of Treponema socranskii (3%), Fusobacterium periodonticum (3%), Capnocytophaga gingivalis (3%), and Spiroplasma ixodetis (3%). The highest mean levels were found for the following species: E. faecium, Dialister pneumosintes, Staphylococcus epidermidis and Helicobacter pylori. There was a statistically significant difference between the levels of gram-negative species and gram-positive species (13.5 × 10(5) vs 6.5 × 10(5), respectively). A positive correlation was found between the area of the periapical lesion and the levels of gram-negative and rod species (P < .05). CONCLUSIONS: The microbiota from teeth with persistent apical periodontitis presents a mixed and complex profile, hosting E. faecium and S. epidermidis as the most highly prevalent species. No correlation was found between any of the species tested and clinical findings; however, periapical lesions with the largest areas presented higher counts of gram-negative and rod species.

Similar expression of through-and-through fluid movement along orthograde apical plugs of MTA Bio and white Portland cement.

AIM: To compare the sealing ability of four hydraulic cements when used as an apical plug in teeth with wide-open apices. METHODOLOGY: A sample of 70 maxillary central incisors were divided into four groups (n = 15) and a further 10 teeth served as controls. An artificial open apex was created in the teeth using Gates Glidden drills numbers 6-1 in a crown-down manner until the size 1 bur passed through the foramen. A divergent open apex was prepared to a size of 1.24 mm at the foramen by retrograde apical transportation using a number 8 (0.60) Profile Series 29 0.4 taper instrument inserted to the length of the cutting blade. In G1, the open apices were repaired with WMTA Angelus whilst in G2, G3 and G4 MTA Bio, Pro-Root MTA and Portland cement was employed respectively. Each root was assembled in a hermetic cell to allow the evaluation of fluid filtration. Leakage was measured by the movement of an air bubble travelling within a pipette connected to the teeth. Measurements of the air bubble movement were made after 10 min at a constant pressure of 50 cm H(2)O. The Kruskal-Wallis H-test was applied to the fluid flow data to detect differences between the experimental groups (P < 0.05). RESULTS: Fluid movement occurred in every sample but was variable in all the experimental groups, ranging from 0.61 to 2.45 microL min(-1). There was no significant difference in mean fluid flow between the experimental groups (P > 0.05). CONCLUSIONS: Fluid movement through teeth with open apices and filled with four hydraulic cements was similar. All cements allowed fluid movement.

The effect of the canal-filled area on the bacterial leakage of oval-shaped canals.

AIM: To compare the sealing ability and the canal-filled area (gutta-percha + sealer) of three current filling techniques in oval-shaped canals. METHODOLOGY: A total of 50 oval-shaped root canals were prepared and root filled as follows: G1: lateral condensation (n = 10), G2: System B (n = 10) and G3: Thermafil system (n = 10). All teeth were mounted in a two-chamber apparatus and the coronal access was exposed to human saliva. The appearance of turbidity in the BHI broth over a 15-week period was observed. A cross section of each tooth was made 5 mm from the apex and the samples were prepared for microscopic analysis. Digital image measurements of the cross-sectional area and the area filled by gutta-percha and sealer were performed. Log-rank and Fisher's exact tests were used to analyse the leakage data. Student's t-test was used to analyse the filled-area data. RESULTS: Overall, 30% of the specimens of G1 and G2 and 20% of G3 demonstrated leakage after 15 weeks and no significant difference was found amongst the groups (P > 0.05). The percentage of canal-filled area was 68, 70 and 78%, respectively (P > 0.05). The correlation analysis revealed no significant relation between the pattern of bacterial leakage and canal-filled area (P = 0.128). CONCLUSIONS: No significant difference in apical sealing and canal-filled area in oval-shaped canals was seen between the three filling techniques. No significant correlation was found between the quality of the apical seal and the filled-area of the root canal space.

Programming features of the CLARION Multi-Strategy Cochlear Implant.

Because patient performance with multichannel cochlear implants varies widely, cochlear implant systems must address the diverse needs of patients during the postoperative fitting of the external equipment. This paper describes the processing strategies available with the CLARION Multi-Strategy Cochlear Implant and the different programming features available for optimization of these speech processing strategies. In addition, preliminary data are presented about the frequency of use of various fitting parameters with adult Simultaneous Analog Stimulation (SAS) and Continuous Interleaved Sampler (CIS) patients and pediatric CIS users. The data reveal that many of the programming features available to the clinician are useful with both the adult and pediatric populations and across strategies. The flexibility of both processing strategies and the programming options clearly contribute to the optimization of patient device fittings. Optimized device fittings, in turn, maximize patient performance.

Misoprostol: una nueva alternativa para el tratamiento del aborto incompleto / Misoprostol: a nuew alternative for theMisoprostol: a new alternative for the incomplete abortion treatment

El objetivo de este trabajo es determinar la eficacia del uso del misoprostol oral, como alternativa al legrado evacuador en el aborto incompleto. Se estudio prospectivamente un grupo de 47 pacientes con diagnóstico clínico y ecográfico de aborto incompleto del primer trimestre

Estudio comparativo entre anestesia general vs. anestesia peridural en cesáreas electivas / Comparative estudy among general anesthesia vs. periddural anesthesia en elective cesarean

Existe una creciente tendencia hacia el uso de anestesia regional en cesáreas electivas. Dicho tipo de anestesia, permite que la madre esté despierta, disminuye el riesgo de aspiración materna, y evita la depresión neonatal por las drogas anestésicas. Por otro lado, se ha registrado un índice mayor de acidemia neonatal en los niños nacidos po4 cesárea con anestesia regional

Misoprostol: una nueva alternativa para el tratamiento del aborto incompleto / Misoprostol: a nuew alternative for theMisoprostol: a new alternative for the incomplete abortion treatment

El objetivo de este trabajo es determinar la eficacia del uso del misoprostol oral, como alternativa al legrado evacuador en el aborto incompleto. Se estudio prospectivamente un grupo de 47 pacientes con diagnóstico clínico y ecográfico de aborto incompleto del primer trimestre(AU)

Estudio comparativo entre anestesia general vs. anestesia peridural en cesáreas electivas / Comparative estudy among general anesthesia vs. periddural anesthesia en elective cesarean

Existe una creciente tendencia hacia el uso de anestesia regional en cesáreas electivas. Dicho tipo de anestesia, permite que la madre esté despierta, disminuye el riesgo de aspiración materna, y evita la depresión neonatal por las drogas anestésicas. Por otro lado, se ha registrado un índice mayor de acidemia neonatal en los niños nacidos po4 cesárea con anestesia regional(AU)

Hyperactivated motility is coupled with interdependent modifications at axonemal and cytosolic levels in human spermatozoa.

Whether the motility characteristics of hyperactivated spermatozoa were determined by stable changes at the axonemal level and whether the presence of cytosolic factors was required for the expression of these changes was investigated. Different degrees of sperm hyperactivation were produced in Percoll-washed spermatozoa after incubation for 1 hour to 3 hours at 37 degrees C in Ham's F-10 supplemented with human blood plasma or fetal cord serum. Decomplemented fetal cord serum induced the highest percentage of hyperactivation (19 +/- 3%), followed by human plasma (13 +/- 2%). Fetal cord serum that was not decomplemented did not induce a level of hyperactivation (1.7 +/- 0.2%) significantly different from control levels (0.9 +/- 0.2%). Dialyzed fetal cord serum induced intermediate levels of hyperactivation (6 +/- 1%). The motility characteristics of demembranated sperm models of hyperactivated spermatozoa induced by decomplemented fetal cord serum and nonhyperactivated spermatozoa were compared by videomicroscopy and computer-assisted digital image analysis. After demembranation with Triton X-100 and reactivation of motility by Mg. adenosine triphosphate (Mg.ATP), hyperactivated and nonhyperactivated spermatozoa showed similar motility characteristics. However, hyperactivated spermatozoa that were demembranated and reactivated in cytosolic extracts from hyperactivated spermatozoa had significantly higher (P less than 0.05) linear velocity (33 +/- 4 mu/sec) and lower linearity (0.23 +/- 0.04) than control spermatozoa that were demembranated and reactivated in control cytosolic extracts (velocity = 24 +/- 1 mu/sec; linearity = 0.32 +/- 0.02). The data suggest that the expression of hyperactivated motility requires interdependent changes at the axonemal and cytosolic levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of two iron-chelators, desferrioxamine and diethylenetriaminepentaacetic acid, on the development of tolerance to the physical dependence on ethanol in mice.

Physical dependence on ethanol was induced in mice by exposing the animals to increasing concentrations of ethanol vapor for a period of 9 days. The degree of dependence was assessed by subjective scoring of a characteristic behavioral withdrawal syndrome upon cessation of ethanol administration. The daily administration of desferrioxamine (350 mg/kg, i.p.) or of diethylenetriaminepentaacetic acid (200 mg/kg, i.p.) during the ethanol treatment period reduced by 50% the behavioral withdrawal score. On the other hand, an iron-load of 250 mg/kg administered once prior to ethanol treatment and once during ethanol exposure caused a significant increase in the withdrawal score. While the degree of dependence was significantly lowered by the iron chelators, the state of tolerance after chronic ethanol treatment was not altered by these agents. However, the capacity of these ethanol-treated animals to develop rapid functional tolerance at termination of the chronic ethanol exposure was significantly enhanced by desferrioxamine and diethylenetriaminepentaacetic acid. The results are discussed in view of possible role of iron-induced peroxidation of neuronal membrane lipids in the development of tolerance to and dependence on, ethanol.

Reduction in severity of physical dependence on ethanol in mice caused by desferrioxamine administration.

Male Swiss mice, when exposed to increasing concentrations of ethanol vapor for a period of 9 days, developed tolerance to as well as physical dependence on ethanol. Desferrioxamine, an iron-chelator and a lipid peroxidation inhibitor, administered to individual mice at a daily dose of 350 mg/kg body weight, caused a reduction in the degree of dependence but not of tolerance. Also, desferrioxamine protected the mice against the reduction in body weight increment observed over the inhalation period. It is suggested that desferrioxamine acts either via inhibiting the ethanol-induced lipid peroxidation, suspected to be involved in dependence, or via a different iron-sensitive mechanism.

Swift increase in alcohol metabolism (SIAM) in the mouse: comparison of the effect of short-term ethanol treatment on ethanol elimination in four inbred strains.

Ethanol metabolism increases 2 to 3 hr after the administration of ethanol. This phenomenon, called the swift increase in alcohol metabolism, has been compared in four inbred strains of mice (DBA/2J, C3H/HeJ, AKR/J and C57BL/6J). Basal rates of ethanol elimination were determined in individual mice after an i.p. injection of ethanol (2 g/kg). Little variability in this basal rate of ethanol elimination was observed within each strain. Mice were then exposed to ethanol vapor (20--22 mg/l) and rates of ethanol elimination were determined every 2 hr for 8 hr. By 2 to 3 hr, the rates of ethanol elimination initially increased 2- to 3-fold and then declined toward basal rates over the 8-hr interval in all strains studied. In another experiment, the dose of ethanol was varied to produce blood ethanol levels ranging from 50 to 250 mg/100 ml in both basal- and ethanol vapor-treated mice. Ethanol elimination increased greater than 1.5-fold in all four strains studied when basal rates were compared to rates observed after 4 hr of vapor treatment at the same blood ethanol level; however, the dose at which the maximal increase occurred differed among the strains. DBA/2J mice exhibited a maximal increase in the rate of ethanol elimination when ethanol concentrations were in the range of 30 to 50 mg/100 ml; the increase was smaller as the dose was increased. In contrast, AKR/J and C57BL/6J mice required 100 to 150 mg/100 ml of ethanol to activate the swift increase in alcohol metabolism effect. These data indicate clearly that the swift increase in alcohol metabolism effect is a common phenomenon and that dose and time relations differ in various inbred strains of mice.

Development and reversal of tolerance and its relationship to physical dependence on ethanol in the rat.

Tolerance to ethanol, as assessed by loss of the righting reflex or by improved performance in the aerial righting reflex test, was only observed in animals which did not show signs of a withdrawal reaction. With long exposure periods to ethanol vapor, tolerance was no longer present in animals exhibiting withdrawal reactions. These data are consistent with the hypothesis that a reversal of tolerance precedes prior to the development of physical dependence on ethanol.

Reversal of tolerance to ethanol associated with the induction of physical dependence on ethanol in the rat.

Three experimental paradigms were employed to investigate the possible relationship between tolerance to and dependence on ethanol in the rat. Groups of rats were exposed to ethanol vapor at various concentrations for different periods of time (e.g., 10 mg/l ethanol vapor for 10 days; 15 mg/l for 0.5 to 10 days; 20 mg/l for up to 12 hours). Tolerance was tested by measuring the concentration of ethanol in the breath at loss of righting reflex of the animal and the withdrawal syndrome was assessed behaviorally. Tolerance developed rapidly and was observed to reverse in association with the development of physical dependence.

Hepatic triglyceride accumulation and the ethanol physical withdrawal syndrome in mice.

Physical dependence on ethanol was induced in TO strain mice by chronic administration of ethanol by inhalation. The severity of the behavioral syndrome of withdrawal from ethanol was quantified by a subjective scoring method. During the chronic administration of ethanol, triglycerides accumulated in livers of male or female mice with a time course similar to that of the induction of physical dependence. When ethanol was withdrawn from adult or weaning dependent mice, a relationship was observed between the decline of triglyceride concentrations in liver and the duration of the ethanol withdrawal syndrome. The addition of DL-carnitine (7% w/w) to diet during the administration of ethanol markedly inhibited the accumulation of triglycerides, and significantly reduced the intensity of the ethanol withdrawal syndrome. Administration of carbon tetrachloride ((1.3 ml/kg i.p.), however, although augmenting hepatic triglyceride accumulation, had no significant effect on the withdrawal syndrome. The results are interpreted as suggesting either that ethanol-induced liver dysfunction plays a part in dependence, or, more likely, that triglyceride accumulation reflects an ethanol-induced metabolic disorder which is itself related to the induction of dependence.