Polychlorinated biphenyls and biotransformation enzymes in three species of sea turtles from the Baja California peninsula of Mexico.

Concentrations of polychlorinated biphenyls (PCBs) as well as the expression patterns of cytochrome P450 (CYP) enzymes and glutathione-S-transferase (GST) activities were measured in livers of loggerhead (Caretta caretta), green (Chelonia mydas), and olive ridley (Lepidocheyls olivacea) sea turtles from the Baja California peninsula of Mexico. The mean concentrations of total PCBs were 18.1, 10.5, and 15.2 ng/g wet weight (ww) respectively for the three species and PCB 153 was the dominant congener in all samples. Total PCB concentrations were dominated by penta- and hexa-chlorinated biphenyls. The mean estimated TEQs were 42.8, 22.9, and 10.4 pg/g (ww) for loggerhead, green, and olive ridley, respectively, and more than 70% was accounted for by non-ortho PCBs. Western blots revealed the presence of hepatic microsomal proteins that cross-reacted with anti-CYP2K1 and anti-CYP3A27 antibodies but not with anti-CYP1A antibody. There were no significant differences in GST activities between species. Grouping congeners based on structure-activity relationships for CYP isoenzymes suggested limited activity of CYP1A contribution to PCB biotransformation in sea turtles. These results suggest potential accumulation of PCBs that are CYP1A substrates and provide evidence for biotransformation capacity, which differs from known animal models, highlighting the need for further studies in reptiles, particularly those threatened with extinction.

Learedius learedi infection in black turtles (Chelonia mydas agassizii), Baja California Sur, Mexico.

Black turtle (Chelonia mydas agassizii) carcasses, recovered as a result of incidental capture in Magdalena Bay, Mexico, revealed invasion by spirorchiid trematode eggs in liver, kidney, intestines, muscle, heart, pancreas, and duodenum. Seventy-five adult Learedius learedi Price, 1934, were recovered from the heart of 1 turtle. Most of the organs showed a mild or absent inflammatory response in histological sections, with the exception of a pancreatic-duodenal section that revealed severe lymphocyte and phagocyte infiltration associated with an infestation of more than 200 eggs. A linear formation of 35 eggs from the pancreas toward the intestinal lumen is described as resembling migration. This is among the first reports of a parasitic infection of L. learedi Price 1934, in C. m. agassizii in Mexico.

Isovaleric acid accumulation in odontocete melon during development.

Biosonar in odontocetes is a highly complex process for gathering information about the surrounding environment. The forehead melon lipid and mandibular lipid tissues, which comprise the region known as the acoustical window for cetacean sound production and reception, have a unique biochemical composition that is made up of unusual fatty deposits rich in isovaleric acid. Although the structure of these acoustical lipids was elucidated three decades ago, little work has been done to determine their origin during cetacean development. The objective of this research was to examine development of the acoustical region by characterizing the accumulation of isovaleroyl lipids throughout cetacean early life stages. Biochemical analyses of melon tissue of Phocoena phocoena and Tursiops truncatus of different sizes (as an indicator of age) demonstrated that the proportion of isovalerate increased significantly with length. These results indicate that the acoustic system is not fully developed at birth and that its biochemical structure changes throughout development.

Risk factors for intermediate-term survival after coronary artery bypass grafting.

BACKGROUND: Risk factors for short-term mortality after coronary artery bypass grafting are well established, but little is known about risk factors for intermediate-term mortality. METHODS: We analyzed the outcomes of 11,815 patients undergoing coronary artery bypass grafting in one of the 43 cardiac surgery programs of the Department of Veteran Affairs. Risk factors for intermediate- and short-term mortality were determined using Cox proportional hazards regression models. Effects of risk factors during these two periods were explicitly compared. RESULTS: We found important differences in mortality risk-factor sets between the intermediate- and short-term periods after coronary artery bypass grafting. The majority of predictors of intermediate-term mortality were noncardiac-related variables, whereas the majority of predictors of short-term mortality were cardiac-related variables. Impaired functional status, chronic obstructive pulmonary disease, and renal dysfunction had greater effects in the intermediate-term period. Previous heart operation, angina class III or IV, previous myocardial infarction, and preoperative use of an intraaortic balloon pump had greater effects in the short-term period. CONCLUSIONS: The risk factors for intermediate-term mortality identified in this study can augment preoperative risk assessment and counseling of patients. Clinicians should be aware of the importance of noncardiac-related variables as predictors of mortality in the intermediate-term period after coronary artery bypass grafting.

Delayed oral estradiol combined with leuprolide increases endometriosis-related pain.

OBJECTIVES: To determine if low-dose estrogen replacement can be added to GnRH agonist therapy after three months to reduce hypoestrogenic symptoms while allowing continued relief of pain in patients with endometriosis. MATERIALS AND METHODS: Thirteen women with endometriosis and pain were treated with six months of leuprolide acetate in a prospective, randomized double-blind placebo controlled study. After three months of therapy, six subjects initiated oral estradiol 1 mg daily, and seven received an identical placebo. RESULTS: Dysmenorrhea improved in both groups, and dyspareunia significantly improved in the GnRH agonist plus placebo group. The mean pain scores of the oral estrogen group tended to be higher than the placebo group, and hot flushes tended to be less severe with estrogen treatment. However, differences observed between the study and placebo groups did not reach statistical significance. CONCLUSION: In a prospective, randomized study, low-dose estrogen replacement increases endometriosis-related pain during GnRH agonist therapy. The study was terminated after the first 13 subjects due to the concerning trend toward recurrent symptoms in women who received oral estradiol during GnRH agonist therapy for endometriosis-related pain. With the trend toward increasing pain with estrogen add-back therapy, a larger study would not seem to be justifiable.

Carbohydrate supplementation of horses during endurance exercise: comparison of fructose and glucose.

To delay the onset of fatigue, endurance horses are often fed at rest stops during races. The resulting increase in blood insulin may adversely inhibit lipolysis. In humans, ingestion of fructose produces a smaller insulin rise than glucose. This study compared glucose and fructose as carbohydrate supplements for endurance horses. Three Arabian geldings were given 300 g of fructose (F), glucose (G) or 50% glucose: 50% fructose (GF), in 1.5 L water, by stomach tube. In the Resting Test, carbohydrate was administered at rest. Following treatment, blood samples were taken every 30 min for 8 h, and feces were collected for 24 h. Treatment did not affect fecal weight or water content. Plasma glucose and insulin responses did not differ among treatments. Post-treatment (60 min), plasma L-lactate tended to be higher (P = 0.06) after the F and GF treatments than after the G treatment. In the Exercise Test, two treadmill exercise bouts at 0 degrees incline (Bout 1: 90 min; Bout 2: 120 min) were separated by a 1-h rest period. A total distance of 36.84 km was covered at a mean speed of 2.9 m/s. Carbohydrate was administered 45 min before Bout 2. Plasma glucose and insulin at the start of Bout 2 were higher (P = 0.02 and 0.03, respectively) with the GF treatment than with the F treatment. However, during exercise, plasma glucose concentrations did not differ among treatments. We conclude that fructose is well-absorbed by horses and rapidly converted to glucose.

Treatment of infected left ventricular assist device using antibiotic-impregnated beads.

There is no well-established therapy for treating infections of heart-assist or artificial heart devices, a serious problem with life-threatening consequences. We used a promising new approach in which antibiotic-impregnated polymethylmethacrylate beads were placed around an implanted left ventricular assist device to control an external blood pump infection in a bridge-to-transplant patient. In this case report, we describe the potential of antimicrobial-impregnated polymethylmethacrylate beads for in situ control of infections involving external surfaces of cardiovascular devices.

Phenotypic involvement in females with the FMR1 gene mutation.

Fragile X syndrome is the most common from of inherited mental retardation. Approximately half of females with the full mutation have significant cognitive deficits, whereas females with the premutation do not. Phenotypic effects seen in 281 females (IQs from 64 to 139) were analyzed. Results showed that females with the full mutation differ significantly from controls on selected anthropometric measurements, physical index score, and various behavioral features. Females with the premutation differed significantly from controls in regards to a few anthropometric measurements and the physical index score but not in behavioral features. These results suggest that phenotypic effects of the FMR1 mutation are not only common in females with the full mutation, but in females with the premutation as well.