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PubMed1996

Longitudinal sealing ability of mineral trioxide aggregate as a root-end filling material.

This study evaluated the ability of mineral trioxide aggregate (MTA) to seal the root end effectively. Seventy-six single-rooted, extracted human teeth were cleaned and shaped using a step-back technique. After root-end resection and ultrasonic preparation, 72 root sections were randomly allocated to three groups and filled with dental amalgam and cavity liner, Super-EBA, or MTA. Microleakage was assessed at 24 h, 72 h, 2 wk, 4 wk, 8 wk, and 12 wk, using a fluid filtration measurement system. MTA demonstrated excellent sealing ability throughout 12 wk of fluid immersion, comparable with that observed for Super-EBA. Microleakage in the MTA group, as well as the Super-EBA group, was significantly less (p < 0.05) than in the amalgam group at 24 h, 72 h, and 2 wk. At the subsequent periods, there were no significant differences among the three materials. In this study, MTA was determined to be superior to amalgam, and comparable with Super-EBA in preventing microleakage when used as a root-end filling.

Aluminum Compounds↗

PubMed1979

Prevention of intraperitoneal adhesions: a comparison of noxythiolin and a new povidone-iodine/PVP solution.

Peritoneal adhesions were induced in 250 female Wistar rats by the excision and closure of a right lower quadrant parietal peritoneal defect. After closure of the defect each rat was randomly allocated to one of five treatment groups: A, control with no instillate; B, control with Ringer solution; C, noxythiolin 0.5 per cent solution; D, noxythiolin 1 per cent solution; E povidone-iodine/PVP solution. Two millilitres of the appropriate solution were injected into the peritoneal cavity just before closure of a standard 4-cm midline incision. Assessment of adhesion formation was made at 1 week in ignorance of the treatment group. Noxythiolin 1 per cent was more effective than Ringer solution and noxythiolin 0.5 per cent in reducing the mean number of adhesions (P less than 0.05) but was inferior to povidone-iodine/PVP (P less than 0.05). Povidone-iodine/PVP solution significantly reduced the number of adhesions compared with the four other groups. In addition, it significantly reduced the mean length of attachment of each adhesion compared with the two control groups (P less than 0.001).

Animals↗

PubMed2000

Tooth preparation techniques for porcelain laminate veneers.

OBJECTIVE: The purpose of this study was to determine the effect that two guides to tooth preparation had on an operator's ability to appropriately and consistently prepare teeth for porcelain laminate veneers. STUDY DESIGN: In-vitro study. MATERIALS AND METHODS: Thirty typodont central incisor teeth were randomly allocated into three groups and a general dental practitioner was asked to prepare the teeth for porcelain laminate veneers. Group A were prepared freehand while Groups B and C were prepared with the assistance of a silicone index and depth preparation bur respectively. Images of the prepared teeth were used to calculate the mean labial depth of preparation and incisal reduction of teeth in each group. RESULTS: The mean labial reduction for Groups A, B and C was 0.37 mm (SD 0.13), 0.62 mm (SD 0.17) and 0.61 mm (SD 0.15) and the mean incisal reduction for Groups A, B and C was 1.0 mm (SD 0.28), 1.0 mm (SD 0.38) and 1.03 mm (SD 0.26) respectively. CONCLUSION: It is suggested that consideration be given to the use of a silicone index or depth gauge bur when teeth are prepared for porcelain laminate veneers.

Dental Instruments↗

PubMed2005

Field experiences on post-cervical artificial insemination in the sow.

The present study was performed in order to evaluate the effects of post-cervical artificial insemination (post-CAI) in eastern European continental climate with multiparous sows. The sows were randomly allocated into two groups, and were AI by using CAI with 3 x 10(9) spermatozoa per dose (group 1, n = 859) or by post-CAI, using pooled semen with 1 x 10(9) spermatozoa per dose (group 2, n = 924). Wean-to-oestrus intervals, duration of oestrus, day 24 pregnancy rates, farrowing rates, and total pigs born were evaluated. Wean-to-oestrus intervals (CAI 114.3 +/- 4.1 h; post-CAI 115.2 +/- 5.2 h), duration of oestrus (CAI 64.1 +/- 4.1 h; post-CAI 65.0 +/- 5.2 h), day 24 pregnancy rates (CAI 90.2 +/- 1.7%; post-CAI 89.3 +/- 1.8%) and farrowing rates (CAI 88.1 +/- 2.3%; post-CAI 87.8 +/- 2.9%) did not differ significantly between CAI and post-CAI inseminated sows. The total number of pigs born differed significantly (p < 0.01) between the groups (CAI 12.3 +/- 1.1; post-CAI 10.2 +/- 0.9).

Animals↗

PubMed1998

Root positioning and leakage to dye in extracted teeth using reduced pressure.

A study was conducted in vitro to assess the root apex position on leakage to dye under reduced pressure (560 mm Hg). A total of 132 extracted single-rooted teeth were randomly allocated to four groups. The teeth were prepared using a step-back technique and sealed with the cold lateral condensation technique, using gutta-percha without sealer. No significant differences (P < 0.813) were found between horizontally positioned experimental groups under reduced pressure and those in passive immersion. In the group in which the apices were in an upright position, the mean leakage was significantly different (P < 0.024) from the mean dye penetration in the group of teeth positioned horizontally under reduced pressure. Those teeth with apices upright allowed the most linear leakage (0.51 mm), whereas the groups in which the roots were horizontally positioned (with and without reduced pressure) had the least dye penetration (0.21 mm and 0.19 mm, respectively). These results show that tooth positioning has a significant effect on linear dye penetration under reduced pressure and emphasize the need to standardize factors that may influence penetration when assessing leakage study methodology.

Coloring Agents↗

PubMed2002

Vascular closure staples reduce intimal hyperplasia in prosthesis implantation.

BACKGROUND: Vascular surgery, like the various other surgical specialities, has seen an increasing demand toward faster and more minimally invasive procedures. One such need is to create a reliable vascular anastomosis that is faster, easier and less damaging to the tissue. The vascular closure staples (VCS*) device provides such characteristics but, to date, no studies have investigated its effectiveness in reducing intimal hyperplasia when used for vascular prosthesis implantation. The present study evaluated its effectiveness compared with suturing of a graft in vascular prosthesis implantation. METHODS: Twelve female Merino sheep underwent gelatin sealed Dacron patch graft implantation into the left and right common carotid artery. Grafts were randomly allocated so that one carotid artery and graft was anastomosed using sutures and the other with VCS*. The two techniques were compared for operation time, clip/suture numbers and blood loss during the implantation procedure. After a 4-week period, the sheep were killed and the grafts were harvested for intimal hyperplasia (IH) assessment. RESULTS: There was a significant reduction in the amount of IH seen in the VCS* group (mean +/- SD: 0.278 +/- 0.079 mm2/mm) when compared with the sutured group (0.575 +/- 0.331 mm2/mm) (P < 0.05). There was also significant reduction in anastomosis time (mean +/- SD: 14 +/- 4.4 min) and fewer points of contact (23 +/- 1.4) using the VCS* compared with suturing (22 +/- 3.2 min, P < 0.01; 27 +/- 3.3, P < 0.05, respectively). CONCLUSIONS: In this model, the VCS* shows several distinct advantages over suturing with significant time saving at operation and, most importantly, the reduction of IH seen at 1 month.

Anastomosis, Surgical↗

PubMed2001

Prevention of postsurgical adhesions with an autocrosslinked hyaluronan derivative gel.

BACKGROUND: ACP gel is a new crosslinked derivative of hyaluronic acid (HA) that displays the biocompatibility properties of its original polymer but has a higher viscosity. It has been demonstrated in an animal model that the gel reduces adhesions after gynecological surgery. The aim of the present study was therefore to investigate the efficacy of ACP gel in increasing viscosity for the prevention of adhesions after abdominal surgery. METHODS: The antiadhesive effect of ACP gel was tested in a controlled randomized study using a standardized animal model of abdominal surgery involving the creation of defects in the parietal peritoneum and muscular fascia and cecal abrasion. The animals (100 female New Zealand white rabbits) were randomly allocated into five treatment groups to receive: ACP gel (1, 2, 4, and 6%) on the injured area or no ACP gel (control). The incidence of adhesions and their grade (score 0-11) were blindly evaluated 10 weeks after surgery. RESULTS: The percentages of adhesion-free animals were 60, 84, 90, and 84% in the 1, 2, 4, and 6% ACP gel concentration groups, respectively, versus 15% in the control group (P = 0.001). The mean adhesion scores were 3.00 +/- 0.91, 1.37 +/- 0.75, 0.65 +/- 0.45, and 1.16 +/- 0.64 in the 1, 2, 4, and 6% ACP gel groups, respectively, versus 7.70 +/- 0.83 in the control group (P < 0.001). CONCLUSION: ACP gel prevents postsurgical abdominal adhesions even at a 1% concentration. This finding may be of clinical importance in situations in which large volumes of antiadhesive solution are required.

Abdomen↗

PubMed2000

Effect of CO(2) pneumoperitoneum on early cellular markers of retinal ischemia in rabbits with alpha-chymotrypsin-induced glaucoma.

BACKGROUND: Increased intraperitoneal pressure in the head-down position is associated with a significant increase in intraocular pressure (IOP) in rabbits with alpha-chymotrypsin-induced glaucoma. Also, the retinal cells are weakened by the induction of increased IOP, and/or glaucoma, even when IOP is controlled by adequate therapy; therefore, these cells need to be protected from any additional aggression. Actin and vimentin are proteins of the retinal cell cytoskeleton that react readily in response to retinal injuries, including ischemia and glaucoma. Early changes in these cytoskeleton proteins determine the morphological changes observed after retinal damage. Therefore, we set out to investigate intracytoplasmic changes in vimentin and actin after a 4-h CO(2) pneumoperitoneum in the head-down position in rabbits with alpha-chymotrypsin-induced glaucoma. METHODS: Twenty-one rabbits with alpha-chymotrypsin-induced glaucoma in one eye received general anesthesia for 4 h in the head-down position and were randomly allocated to have (a) no pneumoperitoneum, (b) a 10 mmHg CO(2) pneumoperitoneum, or (c) a 20 mmHg CO(2) pneumoperitoneum. At the end of the trial, both the right glaucomatous and the left control eyes were enucleated and investigated immunocytochemically for alterations in vimentin and actin, and morphologically for retinal layer disorganization. RESULTS: Except for the preexisting morphological changes induced by glaucoma, both the control and the glaucomatous eyes in all rabbits appeared normal in terms of retinal layer organization and the distribution of intracellular vimentin and actin whatever the intraperitoneal pressure level applied. CONCLUSION: In rabbits with alpha-chymotrypsin-induced glaucoma, a 4-h CO(2) pneumoperitoneum of </=20 mmHg in the head-down position did not induce either retinal layer disorganization or alteration of actin or vimentin.

Actins↗

PubMed2001

Cyathostome fecal egg count trends in horses treated with moxidectin, ivermectin or fenbendazole.

Commercial preparations of fenbendazole (Safe-Guard, Intervet), ivermectin (Eqvalan, Merial) or moxidectin (Quest, Fort Dodge) were administered once to horses scheduled for routine parasiticide treatment. In total, 93 horses from six cooperating farms were used in the study. Computer generated, random allocation of horses to treatment group was conducted at each farm. Fecal egg counts were determined for all horses on trial days 0, 56, 84 and 112, with corresponding calendar dates that were unique to each farm. Only strongyle egg counts from animals which were positive at day 0 were used for analysis of variance and comparisons. Counts for the three treatment groups were similar at day 0, moxidectin<ivermectin<fenbendazole for days 56 and 84, and moxidectin<ivermectin=fenbendazole on day 112 (P<0.05). Reductions of geometric mean egg counts from day 0 levels were 99.1, 97.6 and 94.9% for moxidectin, 16.4, -27.0 and -32.0% for fenbendazole and 85.9, 24.2 and -8.1% for ivermectin on trial days 56, 84 and 112, respectively. Adverse reactions to treatment were not observed for any of the parasiticides.

Animals↗

PubMed1994

Administration of prostaglandin E1 after lung transplantation improves early graft function.

Early graft dysfunction continues to be a major clinical problem after lung transplantation. The objective of this experiment was to determine whether continuous administration of prostaglandin E1 (PGE1) after lung transplantation has a beneficial effect on early graft function. Left lung allotransplantation was performed in 10 size-matched mongrel dogs (weight, 24.4 to 31.4 kg). Lung preservation consisted of a bolus injection of PGE1 (250 micrograms) into the pulmonary artery, followed by a pulmonary artery flush with 50 mL/kg of 4 degrees C modified Euro-Collins solution. The lungs were then stored at 1 degree C for 12 hours. Left lung transplantation was performed using standard technique. The right pulmonary artery and right bronchus were ligated prior to chest closure. Animals were placed in the supine position and ventilated for 6 hours with 100% oxygen at a rate of 20 breaths/min, a tidal volume of 550 mL, and a positive end-expiratory pressure of 5 cm H2O. Animals were randomly allocated to one of two groups. Group I animals (n = 6) received continuous PGE1 infusion from the onset of implantation. The dose was gradually increased and fixed when mean systemic pressure showed a 10% decrease (mean PGE1 dose, 31.7 +/- 6.9 ng.kg-1.min-1). Group II animals (n = 4) received no PGE1. After the 6-hour assessment period, arterial oxygen tension and alveolar-arterial oxygen pressure difference were preserved in group I compared with group II (group I versus group II: arterial oxygen tension, 255.8 +/- 37.6 mm Hg versus 64.7 +/- 7.9 mm Hg [p < 0.05]; alveolar-arterial oxygen pressure difference, 411.1 +/- 70.5 mm Hg versus 597.5 +/- 1.3 mm Hg [p < 0.05]).(ABSTRACT TRUNCATED AT 250 WORDS)

Alprostadil↗

PubMed1984

Comparison of a triphasic oestradiol/norethisterone acetate preparation with and without an oestriol component in the treatment of climacteric complaints.

This study was undertaken to evaluate the effects of oestriol in combination with oestradiol in the treatment of women with climacteric complaints. Forty-three post-menopausal women were randomly allocated to two groups on a double-blind basis. Over a 28-day cycle 23 of the women were treated sequentially for 12 days with 1 tablet containing 17 beta-oestradiol 2 mg plus oestriol 1 mg, then for 10 days with 1 tablet containing the same oestrogens plus norethisterone acetate 1 mg, thereafter for 6 days with 1 tablet containing 17 beta-oestradiol 1 mg plus oestriol 0.5 mg. The other 20 women received the same treatment but without the oestriol. No clinical, laboratory or histological differences were seen between the two groups. Both treatments were found to be equally effective in alleviating climacteric symptoms, with few side effects. It may be stated in conclusion that, on the basis of routine clinical and laboratory parameters no differences were found between the two preparations.

Adult↗

PubMed2002

Rumination and social problem-solving in depression.

We tested the hypothesis that impaired social problem solving in depression is a consequence of state-oriented rumination, which can be ameliorated by improving awareness of mental processes. 32 currently depressed, 26 recovered depressed, and 26 never depressed participants completed the Means Ends Problem Solving Test while randomly allocated to no questions, state-oriented ruminative questions, (e.g. focusing on why you have a problem) or process-focused questions (e.g. focusing on how you decide to solve a problem). In the no question condition, the currently depressed group was significantly impaired at problem solving compared to the never depressed and recovered depressed groups, which did not differ from each other. As predicted, the process-focused questions significantly improved social problem solving in depressed patients, compared to no questions and state-oriented questions, which did not differ from each other. As predicted, compared to the process-focused questions, the state-oriented questions significantly impaired social problem solving in the recovered depressed group. These results are consistent with recent theories and treatment developments which suggest that increased awareness of mental processes can shift people away from ruminative thinking, thereby, reducing depressive relapse.

Adolescent↗

PubMed1984

Failure of weight reduction to reduce mildly elevated blood pressure: a randomized trial.

To determine the value of weight reduction on blood pressure, we randomly allocated 60 untreated, mildly hypertensive, obese individuals to a no-treatment control group or to a behaviourly-oriented weight loss ('diet') programme administered by professional dietitians. Behavioural techniques included self-monitoring, shaping, reinforcement and modelling. Subjects were reassessed after six months by an observer who was unaware of their study group. Fifty-four subjects (90%) completed the study. Diet subjects lost 4.1 kg and controls only 0.8 kg (P = 0.018). However, neither systolic nor diastolic blood pressures differed. The chance that we missed a clinically important diastolic difference of 6 mmHg (our pre-study target) is less than 1%. We conclude that our weight loss programme was successful in reducing weight but that weight loss is not useful in lowering blood pressure in mild, otherwise untreated hypertensives.

Blood Pressure↗

PubMedDate not supplied

The granularity of medical narratives and its effect on the speed and completeness of information retrieval.

OBJECTIVE: Using electronic rather than paper-based record systems improves clinicians' information retrieval from patient narratives. However, few studies address how data should be organized for this purpose. Information retrieval from clinical narratives containing free text involves two steps: searching for a labeled segment and reading its content. The authors hypothesized that physicians can retrieve information better when clinical narratives are divided into many small, labeled segments ("high granularity"). DESIGN: The study tested the ability of 24 internists and 12 residents at a teaching hospital to retrieve information from an electronic medical record--in terms of speed and completeness--when using different granularities of clinical narratives. Participants solved, without time pressure, predefined problems concerning three voluminous, inpatient case records. To mitigate confounding factors, participants were randomly allocated to a sequence that was balanced by patient case and learning effect. RESULTS: Compared with retrieval from undivided notes, information retrieval from problem-partitioned notes was 22 percent faster (statistically significant), whereas retrieval from notes divided into organ systems was only 11 percent faster (not statistically significant). Subdividing segments beyond organ systems was 13 percent slower (statistically significant) than not subdividing. Granularity of medical narratives affected the speed but not the completeness of information retrieval. CONCLUSION: Dividing voluminous free-text clinical narratives into labeled segments makes patient-related information retrieval easier. However, too much subdivision slows retrieval. Study results suggest that a coarser granularity is required for optimal information retrieval than for structured data entry. Validation of these conclusions in real-life clinical practice is recommended.

Cross-Over Studies↗

PubMed1998

[Mechanisms of early gastro-intestinal ischemia after burn: hemodynamic and hemorrheologic features].

OBJECTIVE: To study the mechanisms of early gastro-intestinal ischemia developed in acute burn period and its relationships with hemodynamic and hemorrheologic changes. METHODS: Twelve pigs were randomly allocated into two groups: group C, a sham group that was subjected to all surgical procedures except burn; group B, 30% TBSA cutaneous thermal injury, and was resuscitated with Parkland formula one hour after burn. RESULTS: MAP remained stable after burn, but RAP, MPAP, PAWP and CI decreased significantly to the lowest level 4-8 hours after burn, and recovered after resuscitation 24 hours postburn. Intramucosal pH declined immediately (1 hour after burn) and remained abnormal throughout observation period. Portal venous blood flow demonstrated similar changes as pHi, and correlated well with intestinal pHi. Whole blood viscosity and plasma viscosity in portal venous blood elevated obviously after burn. CONCLUSIONS: 1. GI ischemia occurred early and recovered slowly during burn shock phase with conventional resuscitation regime. 2. GI ischemia correlated significantly with portal venous blood flow, but did not with systemic hemodynamic variables. 3. Hemorheologic changes in portal venous blood may exaggerate ischemia injuries.

Animals↗

PubMed1989

Oral pharmacokinetics of felodipine in patients with congestive heart failure: variable prediction using intravenous data.

Peak and trough concentrations after 8 weeks oral therapy with felodipine, a vasodilating calcium antagonist of the dihydropyridine group, were predicted from intravenous pharmacokinetic data before therapy in 11 patients, randomly allocated to felodipine treatment 10 mg b.i.d., during a placebo controlled study in patients with congestive heart failure. Peak concentrations were well predictable, but trough levels varied between a good agreement in some patients to a large underestimation in others. Predictability was significantly correlated with half life, plasma clearance and distribution volume of the intravenous pharmacokinetic study. After 8 weeks chronic oral therapy no significant differences could be detected between the oral pharmacokinetics of predictable (n = 6) and unpredictable (n = 5) patients. This demonstrates that felodipine kinetics change during felodipine treatment. Differences in the distribution of blood flow before therapy combined with an interindividual variability in blood flow response during therapy is probably responsible for the observed impossibility to calculate trough levels, and thus oral dosage schedules, from intravenous pharmacokinetic data in patients with congestive heart failure.

Administration, Oral↗

PubMed2000

Verapamil reduces intimal hyperplasia in a sheep carotid artery patch graft model.

BACKGROUND: The current study investigated the effect of verapamil on the development of intimal hyperplasia (IH) using a sheep model. METHODS: A gelatin-sealed Dacron patch graft was implanted into the left common carotid artery in 40 adult Merino sheep. Sheep were then randomly allocated to four groups. Group 1 were controls given no treatment (n = 10). Groups 2-4 were treated with intravenous verapamil 0.5 mg/kg per day in two divided doses for different lengths of time. Group 2 (n = 10) received treatment for 1 week; group 3 (n = 10) received treatment for 2 weeks and group 4 (n = 10) received treatment for 4 weeks. All sheep were killed at 4 weeks and the grafted segments of artery were harvested for IH assessment by an image analysis system. RESULTS: The IH index from the three groups treated with verapamil was significantly less than that of the control (group 1,0.287+/-0.077: group 2,0.205+/-0.064, P<0.05; group 3, 0.193+/-0.059, P<0.01; group 4,0.171+/-0.046, P<0.01). CONCLUSION: The present study suggests that verapamil inhibits the development of IH even when treatment is given for only 1 week.

Animals↗

PubMed2003

Pilot study: access to fitness facility and exercise levels in olanzapine-treated patients.

BACKGROUND: Increasingly alarmed by the health risks (that is, weight gain, elevated lipids, and poor glucose tolerance) posed by novel antipsychotic medications, clinicians who treat schizophrenia are attempting to help patients improve lifestyle factors. Unfortunately, schizophrenia research has neglected exercise as a legitimate adjunctive treatment for schizophrenia. OBJECTIVE: To assess the extent to which stable patients with schizophrenia would adhere to an exercise program if offered access to a fitness facility. METHODS: Ten of 20 stable patients with schizophrenia or schizoaffective disorder who were treated with olanzapine for at least 4 weeks had the opportunity to receive access to a Young Men's Christian Association (YMCA) fitness facility, based on random allocation. The intervention included a free membership to the YMCA for 6 months, with access to all the fitness amenities and equipment. The mean dosage of olanzapine was 11.5 mg daily for the YMCA group. RESULTS: Of the 10 subjects, 2 did not attend at all. One subject met criteria for full attendance for each of the 6 months and lost 15 Kg. Dropout rates were as follows: 90% at 6 months, 70% at 5 months, and 40% at 4 months. The main reason they gave for poor attendance was lack of motivation. The mean weight gain was 2 kg in the YMCA group. CONCLUSION: Most subjects did not regularly exercise or attend. They cited poor motivation as the main reason. The subject who exercised regularly lost a significant amount of weight.

Adolescent↗