Dysbiosis of the Fecal Microbiota in Cattle Infected with Mycobacterium avium subsp. paratuberculosis.

Johne's disease (JD) is a chronic, intestinal infection of cattle, caused by Mycobacterium avium subsp. paratuberculosis (MAP). It results in granulomatous inflammation of the intestinal lining, leading to malabsorption, diarrhea, and weight loss. Crohn's disease (CD), a chronic, inflammatory gastrointestinal disease of humans, has many clinical and pathologic similarities to JD. Dysbiosis of the enteric microbiota has been demonstrated in CD patients. It is speculated that this dysbiosis may contribute to the intestinal inflammation observed in those patients. The purpose of this study was to investigate the diversity patterns of fecal bacterial populations in cattle infected with MAP, compared to those of uninfected control cattle, using phylogenomic analysis. Fecal samples were selected to include samples from 20 MAP-positive cows; 25 MAP-negative herdmates; and 25 MAP-negative cows from a MAP-free herd. The genomic DNA was extracted; PCR amplified sequenced on a 454 Roche platform, and analyzed using QIIME. Approximately 199,077 reads were analyzed from 70 bacterial communities (average of 2,843 reads/sample). The composition of bacterial communities differed between the 3 treatment groups (P < 0.001; Permanova test). Taxonomic assignment of the operational taxonomic units (OTUs) identified 17 bacterial phyla across all samples. Bacteroidetes and Firmicutes constituted more than 95% of the bacterial population in the negative and exposed groups. In the positive group, lineages of Actinobacteria and Proteobacteria increased and those of Bacteroidetes and Firmicutes decreased (P < 0.001). Actinobacteria was highly abundant (30% of the total bacteria) in the positive group compared to exposed and negative groups (0.1-0.2%). Notably, the genus Arthrobacter was found to predominate Actinobacteria in the positive group. This study indicates that MAP-infected cattle have a different composition of their fecal microbiota than MAP-negative cattle.

Evaluation of safety and pharmacokinetics of consecutive multiple-day dosing of palonosetron in healthy subjects.

This study evaluated the safety and pharmacokinetics of consecutive multiple-day dosing of palonosetron. Sixteen healthy subjects received an intravenous bolus dose of palonosetron 0.25 mg (n = 12) or placebo (n = 4) daily for 3 consecutive days. Safety was evaluated throughout the study. Serial plasma samples were collected on days 1 and 3 for pharmacokinetic determinations. Three days of dosing with palonosetron 0.25 mg was safe and well tolerated. There were no clinically significant changes from baseline in laboratory values, vital signs, physical examinations, or electrocardiogram intervals. Plasma palonosetron concentrations declined in a biphasic manner, measurable up to 168 hours after dosing on day 3. Mean terminal phase elimination half-life after day 3 dosing was 42.8 hours. The 2.1-fold accumulation of palonosetron in plasma following 3 daily doses was predictable based on elimination half-life of approximately 40 hours, and the maximum plasma concentration remained below the maximum plasma concentration previously observed after a single, well-tolerated 0.75 mg intravenous bolus dose of palonosetron.

Pharmacokinetics of palonosetron in combination with aprepitant in healthy volunteers.

BACKGROUND: Palonosetron is a second-generation 5-HT(3) receptor antagonist with a prolonged duration of action and higher receptor binding affinity than first-generation agents (ondansetron, granisetron, and dolasetron). Aprepitant is a selective antagonist of substance P/neurokinin 1 that augments the benefit of 5-HT(3) receptor antagonists in the prevention of chemotherapy-induced nausea and vomiting. METHODS: This randomized, open-label, two-way, crossover trial was designed to evaluate the effect of oral aprepitant on the pharmacokinetics and safety of a single intravenous (IV) dose of palonosetron in 12 healthy subjects. Treatment A consisted of a single IV bolus dose of palonosetron 0.25mg on day 1. Treatment B added oral aprepitant 125 mg on day 1 (30 minutes prior to palonosetron) and 80 mg on days 2 and 3. Blood for pharmacokinetic evaluations was collected through 168 hours after palonosetron administration on days 1 and 15; safety was monitored through day 22. RESULTS: Mean plasma concentration-time plots for palonosetron were virtually identical for palonosetron administered alone or with concomitant aprepitant. The ratio of geometric least-square mean values (with:without aprepitant) for C(max) was 98.6% (90% confidence interval [CI]: 61.8-157%), and for AUC(0-infinity) the ratio was 101% (90% CI: 85.6-119%). With and without aprepitant coadministration, respectively, mean plasma elimination half-life was 40 hours and 43 hours (difference: -3.0 hours; p = 0.348), mean total body clearance was 130 mL/min and 136 mL/min (difference: -5.6 mL/min; p = 0.735), and mean volume of distribution at steady-state was 410.9 L and 442.3 L (difference: -31.4 L; p = 0.463). Palonosetron alone and the palonosetron/aprepitant regimen were well tolerated. CONCLUSION: These results indicate no significant differences in pharmacokinetic parameters for palonosetron between the two treatments, and suggest that palonosetron can be safely coadministered with aprepitant with no alterations in the expected safety profile and no dosage adjustment necessary.

Mutans streptococci in xerostomic cancer patients after pilocarpine therapy: a pilot study.

OBJECTIVES: Opiod- and/or radiation-induced xerostomia in cancer patients is frequently associated with elevated levels of cariogenic mutans streptococci (MS). STUDY DESIGN: In a single-center, single blind 8-week clinical trial at The University of Texas M. D. Anderson Cancer Center, and from an initial sample of 32 patients, we evaluated MS counts in 28 cancer patients receiving chronic analgesic treatment for cancer pain. All patients received escalating doses of pilocarpine (Salagen) tablets, either 2.5 mg to 5 mg or 5 mg to 7.5 mg qid for 6 weeks, followed by placebo qid for a 2-week washout period. Whole resting saliva flow rates (g/5 min) and MS counts were evaluated at pretreatment, 3 weeks, 6 weeks, and 8 weeks. MS samples were obtained by 5-mL saline rinse (15 sec) at each visit prior to sialometry. RESULTS: In 19 patients (59%), MS counts exceeded 10(5) CFU/mL. At the end of the 6-week trial, 96% of patients showed a positive response to pilocarpine following a 30-minute postdosing evaluation (P=.001). MS counts were lower in 17 patients, higher in 6 patients, and nondetectable before and after pilocarpine in 5 patients (P=.03). CONCLUSION: The reduced MS counts associated with improved saliva flow rates following pilocarpine therapy in this short-term pilot study are encouraging, but further investigation in a larger group of patients over a longer study period is indicated.

Quantitative real-time PCR for detection of neurotoxin genes of Clostridium botulinum types A, B and C in equine samples.

Botulism in horses in the USA is attributed to Clostridium botulinum types A, B or C. In this study, a duplex quantitative real-time PCR (qPCR) for detection of the neurotoxin genes of C. botulinum types A and B, and a singleplex qPCR for detection of the neurotoxin gene of C. botulinum type C, were optimized and validated for equine gastrointestinal, faecal and feed samples. The performance of these assays was evaluated and compared to the standard mouse bioassay (MBA) using 148 well-characterized samples, most of which were acquired from a repository of veterinary diagnostic samples from cases of botulism: 106 samples positive for C. botulinum (25 type A, 27 type B, 28 type C, 1 type D and 25 type E) and 42 negative samples. The sensitivities of the qPCR assays were 89%, 86% and 96% for C. botulinum types A, B and C, respectively. The overall sensitivity of the mouse bioassay for types A, B and C was 81%. The specificities of the qPCR assays were 99-100% and the specificity of the mouse bioassay was 95%.

Successful Treatment of Dry Mouth and Dry Eye Symptoms in Sjögren's Syndrome Patients With Oral Pilocarpine: A Randomized, Placebo-Controlled, Dose-Adjustment Study.

BACKGROUND: : Sjögren's syndrome is characterized by the presence of xerostomia and/or xerophthalmia. Pilocarpine, a muscarinic cholinergic agonist, has been proven to be efficacious in treating radiation-induced xerostomia (up to 30 mg/day) and symptoms of dry mouth in Sjögren's patients (up to 20 mg/day). OBJECTIVE: : To compare the safety and efficacy of oral pilocarpine (dose-adjusted) versus placebo in the treatment of dry eye and dry mouth symptoms in Sjögren's syndrome at 6 and 12 weeks. METHODS: : In this 11-center, 256-patient placebo-controlled study, the safety and efficacy of oral pilocarpine (20 mg to 30 mg daily) for relief of Sjögren's-related dry mouth and dry eye symptoms was assessed. Changes in symptoms and salivary flow were measured over 12 weeks. RESULTS: : Compared with placebo, salivary flow was significantly increased in the pilocarpine group (P