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PubMed1989

Change in plasma acetate levels in diabetic subjects on mixed high fiber diets.

When 10 diabetic (five insulin-dependent) subjects with reasonable glycemic control were randomized from their usual (U) diet (about 30 g fiber/day) between two different but isocaloric high fiber diets, each sequentially over 6 wk [HF (55 g fiber/day) and HFS (55 g fiber/day with sucrose taken as 15 g three times daily, with meals)], plasma acetate (mmol/L) increased by 35% on both high fiber diets from 0.21 +/- 0.06 (SD) to 0.28 +/- 0.10 (HF) and 0.30 +/- 0.10 (HFS) (both p less than 0.01). This was higher than the random weekly variation in plasma acetate levels of 11% in six other glycemically stable diabetic patients. When the acetate value was expressed as acetate/glucose, i.e., relative to the fasting glucose level (since fasting levels of acetate and glucose consistently positively correlate), the increase was about 80%. Fasting plasma non-esterified fatty acid (NEFA) levels fell during the high fiber diets and correlated negatively with the fasting acetate level (rs -0.51, p less than 0.005). The fall in NEFA and rise in acetate levels appeared greatest with the sucrose-supplemented meals. These results suggest increased exogenous contribution to the plasma acetate level from increased colonic fermentation of dietary fiber and raise the possibility of using such measurements in the assessment of compliance to high fiber diets. The fall in NEFA levels associated with raised plasma acetate levels may contribute to the beneficial effects on glycemic control observed with the high fiber diets.

Acetates↗

PubMedDate not supplied

Metabolic conversion of 2-propylpentanal acetals to valproic acid in vitro. Model prodrugs of carboxylic acid agents.

As part of an investigation to test the feasibility of using acetals as precursors of acidic drugs, the dimethyl, diethyl, [2H10]diethyl, and diisopropyl acetals of 2-propylpentanal were synthesized and their metabolic conversion to the anticonvulsant, valproic acid (2-propylpentanoic acid), was investigated. The acetals were incubated with either 10,000g supernatant or microsomes isolated from rat liver. Data from the measurement of the metabolite, valproic acid, with selected ion monitoring gas chromatography/mass spectrometry indicated that the dimethyl, diethyl, [2H10]diethyl, and diisopropyl acetals were substrates. The amount of valproic acid produced from the incubation of 2-propylpentanal diethyl acetal with 10,000g supernatant was reduced by the cytochrome P-450 inhibitor, SKF-525A. The production of acid was also decreased by lack of NADPH or oxygen. These data are consistent with a cytochrome P-450 mediated reaction. 2-Propyl-1-pentanol was the major metabolite identified from microsomal preparations free of soluble fraction enzymes. A deuterium isotope effect calculated as the ratio of the amount of valproic acid produced from unlabeled and [2H5]ethyl-labeled substrate was 1.2. Failure to detect an ester as a metabolite of 3-phenylpropanal diethyl acetal along with the results of the isotope effect studies suggest that the mechanistic pathway of acyclic acetal metabolism involves oxidation of an ether methylene and not oxidation at the acetal carbon.

Acetals↗

PubMed1989

L-lactate for high-efficiency hemodialysis: feasibility studies and a randomized comparison with acetate and bicarbonate.

We evaluated the feasibility of using L-lactate as a base for hemodialysis. In one study, acid-base changes using 40 mM L- or DL-lactate were compared. In a second study, acid-base status using various amounts of L-lactate exclusively was studied. The third study compared symptoms and acid-base changes during 9 weeks of high-efficiency dialysis when using L-lactate, acetate, or bicarbonate as base. In the first study, plasma bicarbonate changes were equivalent with 40 mM L-lactate and 40 mM DL-lactate, but overall correction of acidosis appeared to be suboptimal. In the second study, when compared to a bicarbonate control period, correction of acidosis was reduced when using 40 mM L-lactate + 4 mM acetate solution, but increased when using a 46 mM L-lactate + 4 mM acetate solution. In the third study, correction of acidosis was comparable when using 42 mM L-lactate + 4 mM acetate, 39 mM acetate, or 35 mM HCO3 + 4 mM acetate. Whereas 46% +/- 12 (SEM) treatments "failed" because of symptoms when using acetate, the percentages of "failed" treatments were only 7% +/- 4.2 with L-lactate (p less than 0.05) and 11% +/- 4.2 with bicarbonate (p less than 0.05). The results suggest that L-lactate is a suitable dialysis solution base that is capable of correcting chronic uremic acidosis. During high-efficiency dialysis, the incidence of intradialytic symptoms with L-lactate is comparable to that with bicarbonate and less than that with acetate.

Acetates↗

PubMed1985

Comparison of lipid and androgen levels after conjugated estrogen or depo-medroxyprogesterone acetate treatment in postmenopausal women.

Thirty-five women who had undergone a natural or surgical menopause were randomized to receive either 0.625 mg of conjugated estrogen to be ingested for 25 days each month or 150 mg of depo-medroxyprogesterone acetate intramuscularly every three months. Plasma lipids were determined before and after one year of therapy. Serum androgens were measured before and after six months of therapy. Conjugated estrogens and depo-medroxyprogesterone acetate had similar effects on plasma lipids. Cholesterol was decreased (P less than .02 for conjugated estrogen therapy and P less than .01 for depo-medroxyprogesterone acetate therapy), as was low-density lipoprotein cholesterol (P less than .02 for conjugated estrogen and P less than .05 for depo-medroxyprogesterone acetate). Conjugated estrogens also significantly increased high-density lipoprotein cholesterol (P less than .02). High-density lipoprotein cholesterol levels were unchanged after depo-medroxyprogesterone acetate therapy. Serum androgens were generally unchanged after depo-medroxyprogesterone acetate or conjugated estrogen therapy. The data from this study suggest that long-term conjugated estrogen and depo-medroxyprogesterone acetate treatment have similar effects on lipid and androgen levels except that high-density lipoprotein cholesterol was not significantly increased by depo-medroxyprogesterone acetate.

Adult↗

PubMed1988

Effects of ammonium acetate and sodium cholate on N-methyl-N'-nitro-N-nitrosoguanidine-induced colon carcinogenesis of rats.

This study was conducted to determine the effects of ammonium acetate alone or in combination with sodium cholate upon N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced colon carcinogenesis in rats. Ammonia, acetate, and deconjugated bile acids are produced by microbial enzymes in the gastrointestinal lumen. One hundred twenty male Sprague-Dawley rats, weighing 196 +/- 2 g at 8 wk of age, were given four intrarectal doses of MNNG (2 mg/dose) over 2 wk. They were then randomly assigned among four treatment groups, each containing 30 rats. The groups were arranged in a 2 x 2 factorial design and given intrarectal infusions of the agents under study in 0.3 ml of double-distilled water 3 times weekly for 52 wk beginning 4 wk after the initial MNNG treatment. The experimental treatments were: double-distilled water as control; ammonium acetate (24.8 mg of ammonia); sodium cholate (2 mg of cholic acid); and a combination of ammonium acetate and sodium cholate. Ammonium acetate treatment increased the number of rats with fecal blood 4-fold after 56 wk, and this was associated with a higher incidence of adenocarcinomas with a polypoid morphology. The incidence and total number of carcinomas in situ (high grade dysplasia) increased with ammonium acetate treatment. Ammonium acetate increased the total number of adenocarcinomas. Sodium cholate had no significant main effects on the incidence or morphology of colon lesions. The data support the conclusion that ammonium acetate treatment acted as a promoting agent in MNNG-induced colon carcinogenesis.

Acetates↗

PubMed1981

Effect of acetate or chloride anions on intestinal absorption of water and solutes in the calf.

The influence of acetate, compared with chloride, included in glucose-glycine-sodium formulation was investigated in anesthetized calves, using isolated segments of jejunum or ileum filled with one of the formulations. Maximal absorption of water was observed in the jejunum; this absorption was markedly higher with acetate formulations. The absorption of sodium was highest in the jejunum with the acetate formulation. With the acetate formulation, sodium absorption was still substantial in the ileum, but sodium absorption was maximal with the chloride formulation. Acetate was readily absorbed in the small intestine, particularly in the jejunum, whereas chloride was essentially absorbed in the ileum. With acetate formulations, there was a concomitant secretion of chloride and bicarbonate. These results indicate that acetate favors very efficiently the absorption of water and sodium in the jejunum. In addition, acetate has other interesting properties, such as alkalinizing effects after metabolization.

Acetates↗

PubMed1996

[Supportive treatment with megestrol acetate during radio(chemo)therapy in patients with tumors in the head-neck area. A randomized study].

BACKGROUND: The value of megestrol acetate in treating tumor anorexia and cachexia of terminal patients is well known. However, the supportive effect of megestrol acetate during intensive radio-(chemo-)therapy was not investigated up to now. Therefore a randomized trial was performed including patients with advanced tumors in the head and neck region. PATIENTS AND METHODS: From June 1991 to December 1993 a total of 64 patients were admitted to a randomized, double-blind placebo-controlled study. During and up to 6 weeks following radiotherapy patients received 160 mg/d megestrol acetate or placebo. The nutritional status (anthropometric and laboratory parameters) and the quality-of-life index according to Padilla et al. [24] were determined prior to therapy, 1, 4, 6 weeks later during radiotherapy and 12, 18 weeks after completion. RESULTS: Sixty-one out of 64 patients were evaluable (control group: n = 30; megestrol acetate patients: n = 31). One patient refused further participation after randomization. One patient in each arm was excluded due to side effects (impotence, diarrhoea). Further side effects were not observed. In the control group the nutritional parameters (body weight, triceps skinfold) and the subjective feeling of the patients deteriorated during radiotherapy and did not restore following radiotherapy. By contrast, the patients of the megestrol acetate group were able to stabilize these parameters. This difference was most prominent in the orally nourished patients (weight loss during therapy: control group: -4.1 kg; megestrol acetate group: -0.8 kg; p = 0.004); but not in the patients fed by percutaneous endoscopically guided gastrostomy (weight loss control group: -2.4 kg; megestrol acetate group: -0.8 kg; p = 0.14). CONCLUSION: In patients on radiochemotherapy megestrol acetate prevents patients from further deterioration of the nutritional status and quality of life.

Anthropometry↗

PubMed1997

[Protective role of carnitine in acetate metabolism of patients with uremia treated by hemodialysis].

In 25 patients with chronic renal failure treated by haemodialysis with acetate-37 mEq/l containing fluid, plasma free, total carnitine and acetate concentration before and after HD were assessed. The concentration of acetate was high-12 mmol/l in 4 patients in which carnitine concentration was low. In these patients the incidence of the so-called "dialysis intolerance" or "acetate intolerance" such as acute hypotension, nausea, vomiting and headache were increased. The correlation between the serum acetate level and carnitine level and the symptoms suggest that the acetate overload during acetate dialysis affects acetate metabolism and administration of L-carnitine decreases the amount of accumulated acyl-CoA in the cytosol, and consequently--the citrate cycle function increases and diminish the intolerance symptoms.

Acetates↗

PubMed1998

Long term use of megestrol acetate by cancer survivors for the treatment of hot flashes.

BACKGROUND: Hot flashes are often a troublesome symptom in breast carcinoma survivors and men with prostate carcinoma who have undergone androgen deprivation therapy. A previous clinical study demonstrated that, on a short term basis, low dose megestrol acetate markedly reduced hot flashes and was well tolerated. Little information has been available regarding the long term use of low dose megestrol acetate for hot flashes. METHODS: Patients previously enrolled on a randomized placebo-controlled trial that evaluated the short term use of megestrol acetate for hot flashes were contacted and interviewed by telephone. RESULTS: A total of 132 persons were contacted. Nine percent of the patients discontinued megestrol acetate after resolution of their hot flashes. Forty-five percent of the patients contacted were continuing to utilize megestrol acetate approximately 3 years beyond the conclusion of the 1992 study. Three-quarters of these patients were utilizing < or =20 mg of megestrol acetate per day. Potential toxicities attributed to megestrol acetate included episodes of chills, appetite stimulation/weight gain, vaginal bleeding, and carpal tunnel syndrome symptoms. CONCLUSIONS: A substantial proportion of patients continue to use megestrol acetate for periods of up to 3 years or longer with continued control of hot flashes. This treatment appears to be relatively well tolerated.

Breast Neoplasms↗

PubMed1993

Bowel rest, intravenous hydration, and continuous high-dose infusion of octreotide acetate for the treatment of chemotherapy-induced diarrhea in patients with colorectal carcinoma.

BACKGROUND: A prospective trial was conducted involving 16 patients with colorectal adenocarcinoma using a regimen of continuous-infusion octreotide acetate (Sandostatin [octreotide acetate], Sandoz, East Hanover, NJ for the treatment of severe diarrhea induced by the weekly schedule of 5-fluorouracil (5-FU) in combination with leucovorin who were refractory to opiate therapy. METHODS: Fifteen patients had tissue-documented metastatic colorectal adenocarcinoma. An additional patient was treated adjuvantly. Fifteen patients were treated with chemotherapy consisting of 5-FU and high-dose leucovorin. The octreotide acetate regimen used was a continuous infusion of 50 micrograms/h for 12 hours followed by 100 micrograms/h for 12 hours and subsequently 150 micrograms/h for 72 hours. All patients were previous failures of diphenoxylate atropine (Lomotil diphenoxalate], Searle, Chicago, IL) given 2.5 mg orally after each loose bowel movement, but no more than 20 mg in a 24-hour period. Opiate therapy was not continued beyond 48 hours. All patients also were treated with bowel rest (nothing by mouth) and intravenous fluid hydration as well as octreotide acetate. RESULTS: Complete resolution of diarrhea was seen in 15 of 16 patients (94%). In 4 patients this was accomplished during the 100 micrograms/h infusion, and in 11 patients during the 150 micrograms/h infusion. Recurrence of diarrhea was seen in two patients after a complete cycle of octreotide acetate. Both patients were restarted at 150 micrograms/h for 72 hours of octreotide acetate with resolution of the diarrhea within 36 hours of the infusion. No toxicity related to octreotide acetate was seen in this trial. CONCLUSION: The continuous-infusion regimen of octreotide acetate 150 micrograms/h is an effective and safe schedule for the treatment of chemotherapy-induced diarrhea together with bowel rest and intravenous fluid hydration in a group of patients in whom the majority were treated with the weekly schedule of 5-FU and high-dose leucovorin.

Adenocarcinoma↗

PubMed1986

Effects of B-retinyl acetate on human breast epithelium in explant culture.

Explants of human breast (obtained aseptically from ten women ages 18-37) were examined and the vitamin A compound B-retinyl acetate was tested (at 3 X 10(-5) and 3 X 10(-6) M) for its effects on the fine structure and growth of the epithelium. In the absence of B-retinyl acetate, cells growing out from the explant (outgrowth cells) underwent squamous metaplasia, began to accumulate many intermediate filaments (tonofilaments), and revealed large desmosomes after 2 weeks in culture. In the presence of either concentration of B-retinyl acetate, the epithelial cells were largely prevented from undergoing squamous metaplasia. The glandular epithelium inside the explant maintained a typical secretory appearance for 2 weeks in control cultures (without the retinoid) and then began to show increased numbers of lysosomes and a loss of secretory granules. These glandular epithelial cells did not undergo squamous metaplasia, but they contained increased numbers of intermediate filaments. In contrast, glandular epithelium cultured in either concentrations of B-retinyl acetate appeared secretory for as long 6 weeks in culture, and intermediate filaments were not obvious. Autoradiographs demonstrated that both concentrations of B-retinyl acetate inhibited cell division in the outgrowth epithelium and in the (internal) glandular epithelium. The ability of B-retinyl acetate to reverse squamous metaplasia in the outgrowth cells was also tested. Outgrowth cells reversed to a more normal ductlike appearance after 6 weeks culture in standard medium followed by only 1 week in 20 micrograms/ml B-retinyl acetate. After 7 weeks in standard medium and 1 week in 10 micrograms/ml B-retinyl acetate, the cells showed a partial reversal of the squamous metaplasia.

Adolescent↗

PubMed1996

Methanogenesis from acetate by cell-free extracts of the thermophilic acetotrophic methanogen Methanothrix thermophila CALS-1

High rates of methanogenesis from acetate and ATP were observed from cell-free extracts of the thermophilic acetotrophic methanogen Methanothrix (Methanosaeta) thermophila strain CALS-1 when cultures were grown in a pH auxostat fed with acetic acid. Specific methanogenic activities ranged from 50-300 nmol min-1 (mg protein)-1, which was comparable to those for whole cells. In contrast to results with Methanosarcina spp., the reaction did not require high levels of H2 in the headspace. CO was inhibitory to methanogenesis from acetate. The inhibition by CO and the lack of effect of H2 on methanogenesis from acetate resemble previous results with whole cells of CALS-1. Protein concentrations in extracts > 5 mg/ml were required for good activity, and the optimum temperature for the methanogenesis was near 65° C. ATP was required in substrate quantities and was converted mainly to AMP. The maximum CH4/ATP stoichiometry obtained was near 1.0, consistent with acetate activation using an acetyl-CoA synthetase mechanism that converts ATP to AMP and pyrophosphate. Methanogenesis in extracts was inhibited by bromoethane sulfonate and cyanide, indicating the involvement of methylcoenzyme M methylreductase and a carbon monoxide dehydrogenase complex with methanogenesis from acetate. These results are consistent with acetyl-coenzyme A (CoA) as the form of activated acetate involved in methanogenesis from acetate in strain CALS-1, but no activity could be obtained from extracts using acetyl-CoA as a substrate.

Journal Article↗

PubMed1982

Electrophysiologic effects of flecainide acetate in patients with sinus nodal dysfunction.

Flecainide acetate (R818) is a new antiarrhythmic agent for oral and intravenous use; it has predominantly class I properties and a long plasma half-life. Electrophysiologic effects were evaluated in 11 patients with sinus nodal dysfunction before administration of flecainide acetate and 15 to 60 minutes after intravenous administration of 1.5 mg/kg body weight of flecainide acetate given over 15 minutes. In 8 of 11 patients with maximal sinus nodal recovery time increased after flecainide acetate. However, the mean maximal sinus nodal recovery time was not statistically significantly increased from 1,929 +/- 184 (mean +/- standard error of the mean [SEM]) to 2,770 +/- 500 ms (p less than 0.10). The corrected sinus nodal recovery time increased from 875 +/- 181 before to 1,727 +/- 507 ms after administration of flecainide acetate (p less than 0.05). The sinus cycle length and sinoatrial conduction time were not significantly changed. Flecainide acetate induced a marked prolongation of the H-V interval (from 41 +/- 3 to 52 +/- 4 mg [p less than 0.01]) as well as a significant increase in the A-H interval, QRS duration, and QT100 interval. The effective and functional refractory periods of the atria increased by 12% (p less than 0.01) and 11% (p less than 0.01), respectively. The atrioventricular (AV) nodal functional refractory period increased significantly by 7% (p less than 0.01), whereas the 9% prolongation of the effective refractory period was not statistically significant. No side effects were observed. It is concluded that flecainide acetate prolongs atrial and ventricular conduction and refractoriness, and thus appears to be a potent antiarrhythmic agent. However, the sinus nodal function is depressed, and thus caution is advised in the use of flecainide acetate in patients with sinus nodal dysfunction.

Adult↗

PubMed1990

Octreotide acetate induces fasting small bowel motility in patients with dumping syndrome.

The long acting somatostatin analogue octreotide acetate has been effective in the treatment of early dumping syndrome. We hypothesized that this may be related to its effects on inhibiting gastric emptying and delaying intestinal transit. To study the effect of octreotide acetate on intestinal motility in patients we carried out a randomized, double-blinded study using a subcutaneous injection of either octreotide acetate (100 micrograms) or placebo given 20 min prior to ingestion of a high carbohydrate "dumping" meal in six patients with known severe dumping syndrome. Prior to each study a multilumen polyethylene tube was inserted into the efferent limb to study small intestinal contractions using low compliance pneumo-hydraulic water-perfused manometry. Octreotide acetate prevented dumping symptoms in all six patients and induced the appearance of migrating myoelectric complexes (MMC) characteristic of interdigestive motility. After ingestion of the dumping meal the postprandial "fed" motility pattern lasted for 141 +/- 9 min while after octreotide acetate the fed motility lasted for 29 +/- 5 min (P less than 0.03). The vigor of the fed motility pattern as measured by the motility index (MI = loge (sum of amplitudes X No. of contractions + 1] was lower after octreotide acetate than after placebo (15.1 +/- 0.1 vs 13.4 +/- 0.2, P less than 0.03). The induction of fasting MMC motility pattern and reduction in the duration and vigor of fed motility may explain the symptomatic relief these patients obtained with octreotide acetate. It is not known whether the induction of the MMC is a direct effect of octreotide acetate or secondary to the concomitant inhibition of peptide release (neurotensin, insulin, glucagon, pancreatic polypeptide) that has been demonstrated in earlier studies.

Dumping Syndrome↗

PubMed1991

Combined lead acetate and disulfiram treatment-induced alterations of glial fibrillary acidic protein (GFA) immunoreactive astrocytes in brain smears.

Dithiocarbamates are known to form lipid-soluble complexes with lead and greatly increase brain lead levels. The present study was undertaken to investigate whether lead acetate, when administered together with disulfiram (Antabuse, metabolite of dithiocarbamate) during development, would induce morphological changes in brain astrocytes. Female Sprague-Dawley rats were given 0.25% lead acetate in the drinking water from day one of pregnancy and this treatment was continued after birth until the litters were 4 weeks old. In addition, some dams received disulfiram in a dose of 0.1 mmol/kg p.o. twice weekly and after parturition this dose was given s.c. directly to the offspring twice a week. Lead acetate and disulfiram treatments were discontinued at weaning and animals sacrificed 3 weeks later. Samples of parietal cortex, hippocampal formation and cerebellar cortex were dissected out and smeared onto glass-slides and astrocytes were visualized in toto using immunohistochemistry with antibodies against glial fibrillary acid protein (GFA), enabling morphometric analysis with a computerized image analyser. Animals treated with lead acetate showed a minor increase in the size of the GFA-immunoreactive astrocytes in parietal cortex smears, while animals treated with disulfiram showed no difference in size or form compared to controls. However, in combined lead acetate and disulfiram-treated animals a profound increase in astrocyte size and an increase in the number of processes of the individual GFA-immunoreactive astrocytes could be demonstrated in parietal cortex. No significant changes were noted in GFA-immunoreactive astrocytes of hippocampal smears following the different treatments, while GFA-immunoreactive astrocytes in cerebellar cortex smears were significantly smaller and had reduced number or processes following the combined lead acetate and disulfiram treatment compared to lead acetate treatment or controls. It is concluded that combined exposure to lead acetate and disulfiram during development induces regionally specific changes in GFA-immunoreactive astrocyte morphology. Furthermore, the present study demonstrates the usefulness of smear preparations combined with computerized image analysis to study the morphology of GFA-immunoreactive astrocytes as an index of toxic effects in CNS.

Animals↗

PubMed2005

An in vitro comparison of retentive force and deformation of acetal resin and cobalt-chromium clasps.

STATEMENT OF PROBLEM: The use of metal clasps on anterior teeth may cause esthetic problems. Recently, acetal resins have been used as an alternative tooth-colored denture clasp material to improve esthetics. However, there are few studies to support acetal resin use. PURPOSE: The purpose of this in vitro study was to compare the retentive force and deformation of acetal resin and cobalt-chromium clasps after 36 months of simulated clinical use. MATERIAL AND METHODS: Forty clasps each of acetal resin (1.2 or 2.0 mm thick) and cobalt-chromium (Dentorium)(1.2 mm thick) were fabricated using half-round standard prefabricated clasp patterns. The groups were further subdivided (n=10) into the type of tooth (premolar or molar metal model) and undercut (0.25 mm or 0.50 mm). The retentive force of the clasps was measured in distilled water by a specially designed insertion-removal testing apparatus with intervals corresponding to 0, 6, 12, 18, 24, 30, and 36 months of simulated clinical use of a removable partial denture. The distance between the clasp tips (mm) was measured with a microscope before and after the insertion-removal testing procedure. Comparison of the mean values of the retentive force (gram force) of the clasps and the distance (mm) between the clasp tips was conducted with 3-way analysis of variance and a Least Significant Difference (LSD) multiple range test (alpha=.05). RESULTS: The mean values of tensile load required to dislodge acetal resin clasps with 1.2-mm thickness (111.6 g or 0.11 N) and with 2.0-mm thickness (178.4 g or 1.75 N) was significantly lower than that to dislodge Co-Cr clasps (694.1 g or 6.81 N) (P<.001). The retentive force needed to dislodge all 3 types of clasps was significantly lower for the molar than premolar models and also lower for the models with 0.25-mm undercuts than for those with 0.50-mm undercuts (P<.001). After 36 months of simulated clinical use, there was evidence of deformation in the cobalt-chromium clasps but no deformation noted for the acetal resin clasps. The retentive force of cobalt-chromium clasps (297.4 g or 2.91 N) after deformation remained significantly higher (P<.001) than the retentive force of acetal resin clasps that were 1.2 mm (110.7 g or 1.08 N) and 2.0 mm thick (177.5 g or 1.74 N), respectively. CONCLUSION: Within the limitations of this study, the results suggest that both thicknesses of acetal resin clasps evaluated required less force for insertion and removal than Co-Cr clasps over a simulated 36-month period.

Analysis of Variance↗

PubMed2000

Intermittent leuprolide acetate for the nonsurgical management of women with leiomyomata uteri.

OBJECTIVE: To evaluate the feasibility of intermittent 6-month courses of leuprolide acetate for the long-term control of symptoms attributed to leiomyomata uteri. DESIGN: Prospective open-label feasibility study. SETTING: University department of obstetrics and gynecology. PATIENT(S): Thirty women with abnormal bleeding or discomfort (pain or pressure) due to leiomyomata uteri. INTERVENTION(S): Patients received an initial 6-month course of the GnRH agonist leuprolide acetate, after which they were observed for symptom recurrence. Symptom recurrence was managed by repeated 6-month courses of leuprolide acetate. MAIN OUTCOME MEASURE(S): Relief of symptoms, responses on a quality-of-life questionnaire, serum lipid levels, blood count, and ferritin level. The number of doses of leuprolide acetate required to maintain symptom control was recorded. Serial bone mineral density measurements were made in selected patients. RESULT(S): Twenty of the 30 women who began therapy with leuprolide acetate continued in the protocol. Each individual 6-month course of leuprolide acetate therapy was followed by a median of 9 additional months of symptom control (range, 2 to >25 months). Women remaining in the protocol experienced a mean decrease of 2.4% in bone mineral density of the lumbar spine; bone mineral density of the hip did not change. CONCLUSION(S): Intermittent courses of leuprolide acetate can be used in the nonsurgical management of women with symptomatic leiomyomata uteri. Use of antiresorptive add-back therapy and monitoring of bone mineral density can be considered when repeated courses of leuprolide acetate are given.

Adult↗

PubMed1998

Leuprolide acetate depot and hormonal add-back in endometriosis: a 12-month study. Lupron Add-Back Study Group.

OBJECTIVE: To evaluate the efficacy and safety of a GnRH agonist, leuprolide acetate depot, alone and in combination with three hormonal add-back regimens in the management of endometriosis-associated pelvic pain. METHODS: Two hundred and one patients were enrolled in this multicenter, randomized, double-blind, 1-year trial. All patients were given an intramuscular injection of leuprolide acetate depot 3.75 mg every 4 weeks. Patients were assigned to one of four treatment groups: Group A received placebos for progestin and estrogen, group B received norethindrone acetate 5 mg daily and placebo for estrogen, group C received norethindrone acetate 5 mg and conjugated equine estrogens 0.625 mg daily, and group D received norethindrone acetate 5 mg and conjugated equine estrogens 1.25 mg daily. Pelvic pain scores were assessed monthly, and bone density was measured after 24 and 52 weeks. RESULTS: By week 8, all four groups showed significant improvement in pelvic pain scores compared with baseline levels. A higher proportion of group D patients terminated the study prematurely due to a lack of improvement in symptoms. Group A experienced a 6.3 +/- 2.3% (P < or = .001) loss in bone density after 52 weeks of treatment, whereas bone density was preserved in all three add-back groups. CONCLUSION: The use of leuprolide acetate depot in combination with norethindrone acetate 5 mg alone, or with norethindrone acetate and conjugated equine estrogens 0.625 mg, provides effective suppression of pelvic pain symptoms associated with endometriosis while protecting against bone loss.

Adult↗