Preclinical safety evaluation in rats using a highly purified ethyl ester of algal-docosahexaenoic acid.

Preclinical studies have shown that docosahexaenoic acid (DHA) derived from microalgae (DHASCO) is neither mutagenic nor toxic in acute, subchronic or developmental tests. DHASCO, triglyceride oil from the fermentation of Crypthecodinium cohnii, contains 40-50% (400-500 mg/g) of DHA by weight. Martek Biosciences Corporation has developed a concentrated ethyl ester of DHA (900 mg/g) from DHASCO (MATK-90). A 90-day subchronic safety study with a one-month recovery period using Sprague-Dawley rats included clinical observations, ophthalmic examination, hematology, clinical chemistry, toxicokinetic evaluation, and pathological assessments. Effects of MATK-90 were compared with those produced from DHASCO and control (corn oil). Doses of MATK-90 (1.3, 2.5 and 5.0 g/kg/day) and DHASCO (5.0 g/kg/day=2g of DHA) were administered once-daily by oral gavage at a volume of 10 mL/kg. The corn oil was also administered by oral gavage (10 mL/kg/day). There were no treatment-related adverse effects in any of the parameters measured at doses of

Fungus gnat feeding and mechanical wounding inhibit Pythium aphanidermatum infection of geranium seedlings.

ABSTRACT A series of laboratory tests were conducted to investigate potential effects of fungus gnat (Bradysia impatiens) feeding damage on susceptibility of geranium seedlings (Pelargonium x hortorum) to infection by the root rot pathogen Pythium aphanidermatum. Effects were compared with those from similar tests in which the seedlings were mechanically wounded by severing the root tip with a scalpel. Assays of geranium seedlings in petri dishes revealed a pronounced negative fungus gnat-Pythium interaction, with exposure to fungus gnat larvae 24 h prior to inoculation with P. aphanidermatum zoospores resulting in up to 47% fewer seedling deaths than would have been expected if the two agents had acted independently. Similar results were observed when seedlings were subjected to mechanical wounding 24 h prior to zoospore inoculation. In contrast, no interaction occurred when seedlings were mechanically wounded immediately prior to inoculation. The degree of plant damage inflicted by the feeding activities of the larval fungus gnats had no significant effect on the combined damage from fungus gnats and Pythium in petri dishes. Ancillary studies showed that Pythium development on V8 agar was not inhibited by the presence of fungus gnat-associated microorganisms, nor were seedlings inoculated with these microbes less susceptible to Pythium infection. The precise mechaism or mechanisms underlying the observed interactions were not elucidated; however, the results strongly suggest that both fungus gnat feeding and mechanical wounding activated systemic defenses that made the seedlings more resistant to Pythium infection.

Seed-colonizing microbes from municipal biosolids compost suppress Pythium ultimum damping-off on different plant species.

Composts are known for their suppressive properties toward many different seed- and root-infecting pathogens and diseases. Although disease and pathogen suppression induced by composts is believed to be mediated by microbial activities, the nature of the microbial species and processes responsible for suppressiveness remain unknown. We demonstrated previously that seed-colonizing microbial consortia from leaf compost could explain the observed levels of Pythium ultimum-induced damping-off suppression on cotton. The aim of the present work was to determine whether seed-colonizing microbial consortia could explain Pythium damping-off suppression in municipal biosolids compost on three different plant species. Significant levels of disease suppression were observed on cucumber, wheat, and pea at water potentials of -2 kPa. The suppression of damping-off on cucumber and wheat could be eliminated by autoclaving the compost prior to sowing. High levels of suppressiveness were expressed both on cucumber and on wheat seed surfaces within 8 h of sowing. However, the expression of damping-off suppression on the surface of pea seeds was inconsistent and highly variable. Our results demonstrate that compost-induced suppression of P. ultimum damping-off of cucumber and wheat can be explained by the microbial consortia colonizing seeds within 8 h of sowing. These results further suggest that disease suppression in composts is related to microbial species that interact with the pathogen in its infection court and not in the bulk compost.

Efficacy of nonprescription doses of ibuprofen for treating migraine headache. a randomized controlled trial.

OBJECTIVE: To evaluate the efficacy and safety of ibuprofen, 200 mg and 400 mg, compared with placebo and each other for the treatment of pain of migraine headache. BACKGROUND: Migraine headache is a common illness with significant social and economic impact. DESIGN: Randomized, placebo-controlled, double-blind trial of 6 hours' treatment duration. METHODS: Fifteen investigators at 17 private practice and referral centers in the United States participated in this study of 660 outpatient adults aged 18 to 84 years with migraine headache of moderate to severe intensity. Each patient was randomly assigned to a single dose of study medication: ibuprofen 200 mg (n = 216) or 400 mg (n = 223), or placebo (n = 221). The percentage of patients with a reduction in baseline headache intensity from severe or moderate to mild or none 2 hours after treatment and the headache pain intensity difference from baseline at 2 hours were the primary efficacy measures. Secondary outcomes included other measures of pain relief, severity differences from baseline for migraine-associated symptoms of nausea, photophobia, phonophobia, and functional disability, and percentage of patients with migraine-associated symptoms reduced to none. RESULTS: Significantly (P < or = .006) more patients treated with ibuprofen, 200 mg or 400 mg, reported mild to no pain after 2 hours (41.7% and 40.8%, respectively), compared with those treated with placebo (28.1%). The mean pain intensity difference from baseline measured at 2 hours was significantly (P < or = .001) greater for patients treated with ibuprofen 200 mg or 400 mg (0.68 and 0.65, respectively), compared with those treated with placebo (0.39). Statistically significant differences in favor of both doses of ibuprofen over placebo were observed for mean pain intensity difference at 1 hour after treatment. In patients with severe baseline pain intensity, ibuprofen, 400 mg, was significantly (P < or = .048) superior to placebo for the primary efficacy end points, while ibuprofen, 200 mg, was not. Ibuprofen, 200 mg and 400 mg, were statistically significantly more effective than placebo for all clinically important secondary pain relief outcomes. Mean severity changes of migraine-associated symptoms of nausea, photophobia, phonophobia, and functional disability at 2 and 6 hours were significantly (P < or = .03) in favor of both doses of ibuprofen over placebo, and results for the percentage of patients with symptoms reduced to none consistently, although less often statistically significant, favored ibuprofen. No statistically significant differences in adverse events were found among treatment groups. CONCLUSIONS: Ibuprofen at doses of 200 mg and 400 mg is an efficacious, cost-effective, well-tolerated, single-ingredient nonprescription treatment for pain of migraine headache. In addition, while not always statistically significant, ibuprofen provided a beneficial effect on associated symptoms of migraine including nausea, photophobia, phonophobia, and functional disability.

A placebo-controlled, crossover trial of granisetron in SRI-induced sexual dysfunction.

BACKGROUND: Sexual side effects are commonly associated with serotonin reuptake inhibitor (SRI) therapy. The mechanism underlying SRI-induced sexual dysfunction has been hypothesized to be mediated by direct serotonergic effects. Evidence from open-label reports suggests that cyproheptadine, nefazodone, mirtazapine, and mianserin, which block one or more serotonin receptors, may reverse sexual side effects. The current study was a prospective, randomized, crossover trial comparing granisetron, a serotonin-3 antagonist, with placebo in outpatients who developed sexual dysfunction during SRI treatment. METHOD: Thirty-one outpatients who were currently experiencing sexual dysfunction associated with SRIs were randomly assigned to double-blind treatment with granisetron (1-1.5 mg) or placebo for use 1 to 2 hours prior to sexual activity. Patients rated sexual symptoms after each trial using the Sexual Side Effect Scale (SSES). After 4 trials of the medication, patients crossed over to the other treatment for 4 more trials. RESULTS: Twenty patients received at least 1 dose of placebo and granisetron. Analysis by repeated-measures analysis of variance showed no significant effects of granisetron relative to placebo. Significant improvement between baseline and treatment-phase SSES scores was observed for both granisetron (p = .0004) and placebo (p = .0081). The study medication was generally well tolerated. CONCLUSION: The results of this study do not support the efficacy of granisetron (1-2 mg) in the treatment of SRI-associated sexual side effects. A significant placebo response may be associated with the treatment of SRI-induced sexual dysfunction.

An open trial of olanzapine in the treatment of patients with psychotic depression.

Compared to major depression without psychosis, psychotic depression often responds poorly to treatment with tricyclic antidepressants alone. Atypical antipsychotics, which appear to possess thymoleptic properties, may represent a new treatment alternative for patients with psychotic mood disorders. This open-label, pilot study evaluated the efficacy of olanzapine monotherapy in patients with psychotic depression. Seven inpatients who met DSM-IV criteria for a major depressive episode (unipolar) with psychotic features participated in a 10-week open-label trial of olanzapine 10-20 mg/day. The Hamilton Rating Scale for Depression (HRSD), the Scale for the Assessment of Positive Symptoms (SAPS), and the Clinical Global Impression Scale (CGI) were performed at each visit to evaluate clinical response. Four out of the 5 study completers responded during the trial. Overall, there was a statistically significant change between baseline and final visit on the SAPS, HRSD, and the CGI Scale (p < .001). The results of this pilot study suggest that olanzapine may be an effective treatment for some patients with unipolar psychotic depression. However, these observations require replication in randomized, controlled trials.

Fatty acid competition as a mechanism by which Enterobacter cloacae suppresses Pythium ultimum sporangium germination and damping-off.

Interactions between plant-associated microorganisms play important roles in suppressing plant diseases and enhancing plant growth and development. While competition between plant-associated bacteria and plant pathogens has long been thought to be an important means of suppressing plant diseases microbiologically, unequivocal evidence supporting such a mechanism has been lacking. We present evidence here that competition for plant-derived unsaturated long-chain fatty acids between the biological control bacterium Enterobacter cloacae and the seed-rotting oomycete, Pythium ultimum, results in disease suppression. Since fatty acids from seeds and roots are required to elicit germination responses of P. ultimum, we generated mutants of E. cloacae to evaluate the role of E. cloacae fatty acid metabolism on the suppression of Pythium sporangium germination and subsequent plant infection. Two mutants of E. cloacae EcCT-501R3, Ec31 (fadB) and EcL1 (fadL), were reduced in beta-oxidation and fatty acid uptake, respectively. Both strains failed to metabolize linoleic acid, to inactivate the germination-stimulating activity of cottonseed exudate and linoleic acid, and to suppress Pythium seed rot in cotton seedling bioassays. Subclones containing fadBA or fadL complemented each of these phenotypes in Ec31 and EcL1, respectively. These data provide strong evidence for a competitive exclusion mechanism for the biological control of P. ultimum-incited seed infections by E. cloacae where E. cloacae prevents the germination of P. ultimum sporangia by the efficient metabolism of fatty acid components of seed exudate and thus prevents seed infections.

Placebo-controlled trial of sertraline in the treatment of binge eating disorder.

OBJECTIVE: The authors' goal was to assess the efficacy of sertraline in the treatment of binge eating disorder. METHOD: Thirty-four outpatients with DSM-IV binge eating disorder were randomly assigned to receive either sertraline (N=18) or placebo (N=16) in a 6-week, double-blind, flexible-dose (50-200 mg) study. Except for response level, outcome measures were analyzed by random regression methods, with treatment-by-time interaction as the effect measure. RESULTS: Compared with placebo, sertraline was associated with a significantly greater rate of reduction in the frequency of binges, clinical global severity, and body mass index as well as a significantly greater rate of increase in clinical global improvement. Patients receiving sertraline who completed the study demonstrated a higher level of response, although the effect was not significant. CONCLUSIONS: In a 6-week trial, sertraline was effective and well tolerated in the treatment of binge eating disorder.

A multicenter randomized controlled trial of a liquid loperamide product versus placebo in the treatment of acute diarrhea in children.

This randomized, double-blind, placebo-controlled trial of 48 hours' duration conducted in 13 primary care ambulatory practices in the United States and Mexico was used to compare the efficacy and safety of loperamide with placebo for the treatment of acute diarrhea in children aged 2 through 11 years. Two hundred fifty-eight children with acute nonspecific diarrhea were enrolled. Children were randomly assigned to treatment with loperamide HCl 0.5 mg/5 mL (n = 130) or placebo (n = 128). The first dose of loperamide consisted of either 1.0 mg (children 2 through 5 years of age) or 2.0 mg (children 6 through 11 years of age) of study medication under the observation of study personnel. This was followed by 1 mg after each unformed stool, with a total daily dose of up to 3.0 mg in the children 2-5 years of age, 4.0 mg in the children 6-8 years of age, and 6.0 mg in the children 9-11 years of age. The primary outcome measures were time to last unformed stool, time to first unformed stool, number of unformed stools during six consecutive 8-hour periods, and overall rating of efficacy/acceptability. Secondary outcomes included abdominal pain/cramping, vomiting, and fever. Children who received loperamide had significantly shorter time to last unformed stool (p = 0.0017) and fewer numbers of unformed stools (p = 0.0237) than children who received placebo. The end-of-study overall efficacy/acceptability rating of loperamide was significantly better than for placebo (p = 0.0107). All other clinically important outcome measures related to diarrhea relief favored loperamide. There was no significant difference in the incidence of drug-related adverse events between treatment groups, although total adverse events were reported more frequently (p = 0.048) by the loperamide group (15%) compared with the placebo group (7%). In conclusion, this controlled study provides data demonstrating that at recommend doses, loperamide is well tolerated and significantly shortens the duration and severity of symptoms of acute nonspecific diarrhea in children 2 through 11 years of age.

Psychiatric features of 36 men convicted of sexual offenses.

BACKGROUND: To increase understanding of the relationship between sexual violence and mental illness, the authors assessed the legal histories and psychiatric features of 36 males convicted of sexual offenses. METHOD: Thirty-six consecutive male sex offenders admitted from prison, jail, or probation to a residential treatment facility received structured clinical interviews for DSM-IV Axis I and II disorders. The participants' legal histories, histories of sexual and physical abuse, and family histories of psychiatric disorders were also assessed. RESULTS: The participants' mean +/- SD age was 33+/-8 years. They had been convicted a mean of 1.8+/-1.4 times (range, 1-9 times) for sexual offenses and incarcerated a mean of 8+/-6 years (range, 0-22 years). Participants displayed high rates of lifetime DSM-IV Axis I disorders: 30 (83%) had a substance use disorder; 21 (58%), a paraphilia; 22 (61%), a mood disorder (13 [36%] with a bipolar disorder); 14 (39%), an impulse control disorder; 13 (36%), an anxiety disorder; and 6 (17%), an eating disorder. Participants also displayed high rates of Axis II disorders, with 26 (72%) meeting DSM-IV criteria for antisocial personality disorder. In addition, subjects reported experiencing high rates of sexual (but not physical) abuse and high rates of Axis I disorders, especially substance use and mood disorders, in their first-degree relatives. Compared with subjects without paraphilias, subjects with paraphilias displayed statistically significantly higher rates of mood, anxiety, and eating disorders, as well as significantly higher rates of childhood sexual abuse. CONCLUSION: Recognition and treatment of major psychiatric disorders among sex offenders may increase chances for successful rehabilitation, reduce recidivism and public victimization, and produce significant public health and economic benefits. More studies in this area appear warranted to search for more effective interventions for this severe public health problem.

Loperamide-simethicone vs loperamide alone, simethicone alone, and placebo in the treatment of acute diarrhea with gas-related abdominal discomfort. A randomized controlled trial.

CONTEXT: Acute diarrhea with gas-related abdominal discomfort is a common, usually self-limited disorder with substantial social and economic impact. OBJECTIVE: To compare the efficacy and safety of a loperamide hydrochloride-simethicone combination product with those of loperamide alone, simethicone alone, and placebo in treating acute diarrhea with gas-related abdominal discomfort. DESIGN: Randomized, placebo-controlled, double-blind trial of 48 hours' duration. SETTING: A primary care, ambulatory practice in Acapulco, Mexico. PATIENTS: A total of 493 outpatient adults aged 18 to 63 years, with acute nonspecific diarrhea with at least moderately severe abdominal discomfort. INTERVENTIONS: Each patient was randomly assigned to receive 2 chewable tablets containing loperamide hydrochloride, 2 mg, and simethicone, 125 mg (n = 124); loperamide hydrochloride, 2 mg (n = 123); simethicone, 125 mg (n = 123); or placebo (n = 123). This was followed by 1 tablet after each unformed stool, up to 4 tablets in any 24-hour period. MAIN OUTCOME MEASURES: Time to last unformed stool and time to complete relief of gas-related abdominal discomfort were the protocol-specified primary outcomes. Secondary outcomes included time to complete relief of diarrhea, number of unformed stools, and patient-assessed variables at the end of the study (overall illness relief, diarrhea relief, and abdominal discomfort relief). RESULTS: Patients who received loperamide-simethicone had significantly (P < .001) shorter time to last unformed stool and faster relief of gas-related abdominal discomfort than patients who received loperamide, simethicone, or placebo alone. Loperamide-simethicone was significantly (P < or = .01) more effective than the other 3 treatments for all end-of-study patient-assessed outcomes and all clinically important secondary outcomes. No significant differences in adverse events were found among treatment groups. CONCLUSIONS: The loperamide-simethicone combination chewable product provides faster and more complete relief of acute nonspecific diarrhea and associated gas-related abdominal discomfort (gas pain, cramps, gas pressure, and bloating) than either of its components or placebo. The combination is well tolerated.

An endoscopic comparison of gastroduodenal injury with over-the-counter doses of ketoprofen and acetaminophen.

OBJECTIVE: The objective of this study was to endoscopically assess in healthy subjects the gastrointestinal effects of over-the-counter (OTC) doses of ketoprofen. Ketoprofen is a potent nonsteroidal antiinflammatory agent (NSAID) recently approved for OTC use as an analgesic/antipyretic at doses of 75 mg versus the usual dose of < or = 300 mg daily. In epidemiological studies, ketoprofen at prescription doses has consistently been in the higher relative risk group of NSAIDs in the occurrence of gastrointestinal complications of therapy. The gastrointestinal effects of the OTC (US) dose of ketoprofen have not been reported. METHODS: In a randomized, double blind, three way crossover study, 24 healthy subjects received 7 days of therapy with ketoprofen 75 mg/day, acetaminophen 4000 mg/day, and placebo. Gastroduodenal endoscopy was performed before and at the end of each treatment period. The condition of the mucosa was graded compositely for the gastric antrum, fundus, body, and duodenum. RESULTS: Significantly more frequent and severe gastric mucosal injury was observed after dosing with ketoprofen compared with acetaminophen (p = 0.0001). The acetaminophen group showed no difference from placebo (p = 0.8783). Two subjects developed frank gastric ulcers with ketoprofen therapy. Marginally more frequent (p = 0.0703) and significantly more severe (p = 0.0117) duodenal mucosal injury was seen. No significant differences were observed between treatment groups with respect to subjective symptoms of gastric discomfort or adverse events. CONCLUSION: These results indicate that even at lower (OTC) doses (75 mg/day) ketoprofen is associated with significant gastrointestinal irritation.

Attentional performance in patients with psychotic and nonpsychotic major depression and schizophrenia.

OBJECTIVE: The authors examined Continuous Performance Test scores of patients with major depression with or without psychosis and schizophrenia. METHOD: Patients with major depression with psychosis (N = 13), major depression without psychosis (N = 14), and schizophrenia (N = 15) and normal volunteers (N = 14) completed the degraded-stimulus version of the Continuous Performance Test. Patients were rated with the Hamilton Depression Rating Scale and measures of positive formal thought disorder. RESULTS: Continuous Performance Test scores of patients with major depression with psychosis and schizophrenia were significantly worse than those of patients with major depression without psychosis and of normal volunteers. Positive formal thought disorder was correlated with performance on this test in patients with schizophrenia. CONCLUSIONS: These findings suggest that attentional impairment on the Continuous Performance Test is associated with psychosis in general and may be specifically associated with positive formal thought disorder in patients with schizophrenia.

Ecological Studies of Transformed Trichoderma harzianum Strain 1295-22 in the Rhizosphere and on the Phylloplane of Creeping Bentgrass.

ABSTRACT A beta-glucuronidase (GUS) reporter gene and a hygromycin B (hygB) phosphotransferase gene were integrated separately into the Trichoderma harzianum strain 1295-22 genome, using biolistic transformation. The mycelial growth and biocontrol ability of the transformed strains did not differ from that of the original strain. The transformed Gus(+)-kanamycin-resistant (Gus(+)Kan(R)) strains were used to monitor growth and interactions with Rhizoctonia solani on creeping bentgrass plants. The hygB-resistant (hygB(R)) strains were used to selectively recover strain 1295-22 from the rhizosphere soil and phylloplane of creeping bentgrass after spray applications. The population levels of two hygB(R) strains and the original strain were very similar for all treatments. All three strains persisted for the duration of the experiment (28 days) in both the rhizosphere soil and on leaves, although population levels declined somewhat over the course of the experiment in unautoclaved soils. In this study, the results demonstrated that hygB(R) strains remained dominant over time when assayed on Trichoderma-selective medium containing hygB. The hygB(R) strains were not displaced by strains that colonized untreated plants. Microscopic observation showed that the Gus(+)Kan(R) strains colonized the rhizoplane, seed coat, and phylloplane of creeping bentgrass. These results supported our earlier observation that strain 1295-22 was rhizosphere and phyllo-plane competent. Interactions between T. harzianum and R. solani were readily observed in situ and changed over time. Two types of reactions were found in these experiments. In the first type, sections of hyphae of R. solani near the hyphae of T. harzianum appeared damaged, and the pathogen appeared necrotic when viewed with a microscope. The second type, observed less frequently than the first type, was typical of myco-parasitism. The findings in this study provide new insight into the interactions between R. solani and T. harzianum, providing a basis for future research.

Improved Biocontrol Efficacy of Trichoderma harzianum 1295-22 for Foliar Phases of Turf Diseases by Use of Spray Applications.

Trichoderma harzianum strain 1295-22 is an effective biocontrol agent for several fungal diseases. The efficacy of granule and spray applications of strain 1295-22 for control of Pythium root rot, brown patch, and dollar spot of creeping bentgrass was investigated. Spray applications of conidial suspensions (SA) of strain 1295-22 significantly reduced all three diseases of creeping bentgrass turf in both greenhouse and field experiments. Control was greatest when Triton X-100 at 0.1% was added to aqueous spray suspensions. When SA were applied weekly, the biocontrol treatments were equivalent to standard fungicides. Broadcast granule applications (GA) also significantly reduced foliar symptoms of Pythium root rot, dollar spot, and brown patch; turf quality also was enhanced. The populations of Trichoderma spp. in the root zone of a bentgrass putting green treated with SA or GA of strain 1295-22 increased 10- to 100-fold after treatment compared with untreated plots. However, strain 1295-22 was present at high levels on bentgrass leaves only following SA. Collectively, the results suggest that strain 1295-22 possesses both rhizosphere and phylloplane competence. The combination of broadcast applications of granules followed by spray applications of conidia reduced damage from both root and foliar diseases.

Microbial Properties of Composts That Suppress Damping-Off and Root Rot of Creeping Bentgrass Caused by Pythium graminicola.

Composts prepared from a variety of feedstocks were tested for their ability to suppress seedling and root diseases of creeping bentgrass caused by Pythium graminicola. Among the most suppressive materials in laboratory experiments were different batches of a brewery sludge compost and a biosolids compost from Endicott, N.Y. Batches of these composts that were initially not suppressive to Pythium damping-off became more suppressive with increasing compost age. Leaf, yard waste, food, and spent mushroom composts as well as certain biosolids, cow manure, chicken-cow manure, and leaf-chicken manure composts were not suppressive to Pythium damping-off. In some cases, turkey litter, chicken manure, chicken-leaf, and food waste composts were inhibitory to creeping bentgrass seed germination in laboratory experiments. Microbial populations varied among all of the composts tested. Bacterial populations were high in all composts except the turkey litter compost, in which populations were 1,000- to 10,000-fold lower than in the other composts tested. Among the highest populations of heterotrophic fungi and antibiotic-producing actinomycetes were those found in all batches of the brewery sludge compost, whereas the lowest populations were found in turkey litter, chicken manure, and food waste composts. Heat treatment of suppressive composts reduced populations of bacteria, fungi, and actinomycetes in all composts tested. Disease suppressiveness was also reduced or eliminated in heated composts. Amending heated composts with small amounts of nonheated compost restored suppressive properties and partially restored microbial populations to wild-type levels. A strong negative relationship between compost microbial activity (as measured by the hydrolysis of fluorescein diacetate) and Pythium damping-off severity was observed. When composts were applied to creeping bentgrass in field experiments, a significant level of suppressiveness was evident with some composts when disease pressure was high (i.e., disease ratings high in uninoculated plots). A 1991 batch of turkey litter compost and the 1990 batch of Endicott biosolids were consistently suppressive to foliar symptoms of Pythium root rot on creeping bentgrass. This study indicates that suppression of Pythium diseases of creeping bentgrass in batches of brewery sludge and Endicott biosolids composts, and possibly in other suppressive composts examined in less detail in this study, is related directly to the microbial activities in the composts. On the other hand, the mechanisms of Pythium suppression in turkey litter and perhaps other poultry-based composts is not related directly to the compost microbial activity. Although turkey litter showed a lack of suppressiveness in laboratory bioassays and low microbial populations and activity, it resulted in a significant and consistent level of suppressiveness in field experiments. Therefore, the microbiological properties of Pythium-suppressive composts may differ substantially, and measurements of microbial populations and activity may not be predictive of the level of disease suppression in all composts.