Facultative Parthenogenesis in California Condors.

Parthenogenesis is a relatively rare event in birds, documented in unfertilized eggs from columbid, galliform, and passerine females with no access to males. In the critically endangered California condor, parentage analysis conducted utilizing polymorphic microsatellite loci has identified two instances of parthenogenetic development from the eggs of two females in the captive breeding program, each continuously housed with a reproductively capable male with whom they had produced offspring. Paternal genetic contribution to the two chicks was excluded. Both parthenotes possessed the expected male ZZ sex chromosomes and were homozygous for all evaluated markers inherited from their dams. These findings represent the first molecular marker-based identification of facultative parthenogenesis in an avian species, notably of females in regular contact with fertile males, and add to the phylogenetic breadth of vertebrate taxa documented to have reproduced via asexual reproduction.

Safety, efficacy, and pharmacokinetics of balsalazide in pediatric patients with mild-to-moderate active ulcerative colitis: results of a randomized, double-blind study.

OBJECTIVES: : A multicenter, double-blind study was conducted to evaluate the safety, efficacy, and pharmacokinetics of balsalazide in pediatric patients with mild-to-moderate ulcerative colitis (UC). PATIENTS AND METHODS: : Sixty-eight patients, 5 to 17 years of age, with mild-to-moderate active UC based on the modified Sutherland UC activity index (MUCAI) were randomized to receive oral balsalazide 2.25 or 6.75 g/day for 8 weeks. The primary endpoint was clinical improvement (reduction of the MUCAI score by > or =3 points from baseline). Clinical remission (MUCAI score of 0 or 1 for stool frequency) and histological improvement after 8 weeks were also assessed. Pharmacokinetic parameters for balsalazide, 5-aminosalicylic acid, and N-acetyl-5-aminosalicylic acid were determined at 2 weeks. Adverse events and laboratory changes were monitored throughout the study. RESULTS: : Clinical improvement was achieved by 45% and 37% of patients and clinical remission by 12% and 9% of patients receiving 6.75 and 2.25 g/day, respectively. Improvement in histologic grade was achieved by 8 of 16 (50%) and 3 of 10 (30%) patients receiving 6.75 and 2.25 g/day, respectively. No significant differences were seen in efficacy. Pharmacokinetics in 12 patients were characterized by large interpatient variability and low systemic exposure. Adverse events were similar between the treatment groups, the most common being headache and abdominal pain. No clinically significant changes were observed in laboratory values, including those indicative of hepatic or renal toxicity. CONCLUSIONS: : Balsalazide is well tolerated and improves the signs and symptoms of mild-to-moderate active UC in pediatric patients 5 to 17 years of age.

A randomized, multicenter study comparing the safety and efficacy of sodium phosphate tablets with 2L polyethylene glycol solution plus bisacodyl tablets for colon cleansing.

OBJECTIVE: The safety and efficacy of NaP tablets have not been compared with 2L PEG lavage solution. A multicenter, investigator-blinded study was conducted to compare the colon-cleansing efficacy of a new NaP tablet formulation with that of 2L PEG solution plus bisacodyl tablets in adults undergoing colonoscopy. METHODS: A total of 481 patients were randomized to receive either 32 tablets (48 g) of NaP or 2L PEG solution plus 4 (20 mg) bisacodyl tablets. Quality of colon cleansing was assessed using a 4-point scale (1 = excellent, 2 = good, 3 = fair, and 4 = inadequate), and the primary efficacy end point was mean overall colon-cleansing score. Safety assessments included recording of adverse events and changes in biochemical tests and vital signs. RESULTS: A total of 411 patients were included in the efficacy analysis. The mean overall and ascending colon-cleansing scores for NaP tablets were significantly better than PEG plus bisacodyl (overall 1.5 vs 1.8, ascending 1.4 vs 1.8, P < 0.0001 for both). Patients treated with NaP tablets experienced significantly fewer adverse events (66%vs 82%, P= 0.0003) and gastrointestinal symptoms (64%vs 79%, P= 0.0001) compared with patients receiving PEG plus bisacodyl. Patients receiving NaP tablets were significantly less likely to experience abdominal distention, abdominal pain, and vomiting than patients receiving PEG plus bisacodyl (P < 0.0012). Transient fluctuations in laboratory parameters were observed in both treatment groups; however, the fluctuations were more common and of greater magnitude in the NaP group particularly in phosphorous, sodium, and potassium. CONCLUSION: The colon-cleansing efficacy of the new 32-tablet NaP dosing regimen in this study was found to be significantly better than the 2L PEG solution plus bisacodyl tablets regimen. The 32-tablet NaP dosing regimen was associated with fewer adverse events. As expected electrolyte shifts were more common and of greater magnitude in the NaP group compared with the PEG plus bisacodyl group; however, both treatment groups demonstrated significant changes in electrolytes and creatinine.

Safety and colon-cleansing efficacy of a new residue-free formulation of sodium phosphate tablets.

OBJECTIVE: A residue-free sodium phosphate tablet (RF-NaP) was formulated that lacks microcrystalline cellulose, which can appear as a whitish residue in the colon. A multicenter, randomized, investigator-blinded study was conducted to compare the colon-cleansing efficacy of 40 or 32 tablets of RF-NaP with the marketed 40-tablet NaP treatment regimen. METHODS: Eight hundred sixteen patients were randomized prior to colonoscopy to receive either 40 tablets (60 g) of NaP or RF-NaP or 32 tablets (48 g) of RF-NaP. Colon cleansing was assessed using a 4-point scale based on retained "colonic contents." The primary end point was overall colon-cleansing response rate to treatment (score of excellent/good) versus nonresponse (fair/inadequate). RESULTS: Seven hundred four patients were included in the efficacy analysis. The overall colon-cleansing response rates were comparable among treatment arms (94.5%, 97.0%, and 95.3% for NaP, RF-NaP 40, and RF-NaP 32 tablets, respectively). Ascending colon-cleansing response rates for RF-NaP 40 (95.7%) and 32 tablets (93.6%) were significantly better than for NaP tablets (88.5%, p < 0.03 for both). Patients treated with RF-NaP 32 tablets experienced less pronounced changes in electrolyte levels and fewer adverse events (138/239, 58%) compared with patients receiving NaP (161/238, 68%, p= 0.07) and RF-NaP 40 tablets (156/236, 66%, p= 0.03). The most common adverse events reported were abdominal distention, nausea, abdominal pain, and vomiting. CONCLUSIONS: Based on the safety, efficacy, and patient preferences, the 32-tablet RF-NaP regimen was superior to the 40-tablet RF-NaP and NaP regimen for colon cleansing prior to colonoscopy.