The reproductive cycle of the female American alligator (Alligator mississippiensis)

We examined ovarian and oviducal gross morphology and collected blood samples from wild female alligators in central Florida during most of the year. Females with vitellogenic follicles were observed throughout the year, although ovaries containing follicles larger than 15 mm were seen only during the spring and early summer (March-June). We detected a poor relationship between female body size and the number of vitellogenic follicles whereas body size was significantly correlated with clutch size. Plasma samples were analyzed for (1) estradiol-17beta (E2), testosterone (T), and corticosterone by specific radioimmunoassays; (2) vitellogenin by one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis; and (3) total protein, phosphorus, and calcium by spectrophotometric assays. Reproductively active females showed elevated plasma concentrations of E2 during the fall (September-November) and spring (March-May) whereas non-reproductively active females exhibited basal levels with no apparent peaks. Vitellogenin was detected in the plasma during the same months that plasma E2 concentrations were elevated. Elevated plasma vitellogenin and E2 were not correlated with plasma total protein but were correlated with plasma calcium concentration. During late vitellogenesis, plasma T concentrations were elevated in reproductively active females coincident with a period of intense courtship and mating. Corticosterone plasma concentrations exhibit no significant monthly variation, nor apparent changes during various stages of reproductive activity although plasma concentrations were elevated during late gravidity. Our data suggest that female reproductive activity begins in the fall with an increase in plasma E2 concentration in September or October and vitellogenesis in October. Ovarian activity slows during winter and reactivates with the onset of spring.     

Long-term interferon-alpha therapy does not affect sex hormones in males with chronic hepatitis C

The effects of interferon-alpha (IFN-alpha), given at a dosage of 6 MU thrice weekly for 12 months, on gonadal function were investigated in 18 males affected by chronic hepatitis C. Periodically, all patients were clinically monitored and questioned about sexual function. Gonadotropin and serum androgen concentrations (follicle-stimulating hormone, luteinizing hormone, total testosterone, free testosterone, androstenedione, dehydroepiandrosterone, dehydroepiandrosterone sulfate, and sex hormone binding globulin) were tested every 3 months. Ten of 18 patients (55%) responded to IFN-alpha therapy. Serum total testosterone and sex hormone binding globulin values decreased slightly at the third month of treatment, then returned to baseline values. Serum free testosterone and other sex hormones remained essentially unchanged during IFN-alpha therapy. Four patients (22.2%) complained of sexual dysfunction (impaired libido, erectile failure, and impaired ejaculation), which was unrelated to any significant hormonal change and resolved after IFN therapy was stopped. Serum sex hormones values did not differ between responders and nonresponders to IFN-alpha. This study indicates that 12 months treatment with 6 MU of IFN-alpha thrice weekly does not significantly affect gonadal function in men with chronic hepatitis C. The sexual dysfunction observed could be ascribed to such other side effects of IFN as asthenia, fatigue, or anxiety, or it could have a psychologic basis.     

Eosinophilic pulmonary arteritis in a full-term fetus with hypereosinophilia

The case refers to a term-fetus, small-for-date, with polydramnios, idiopathic hypereosinophilic syndrome and eosinophilic vasculitis of large, medium and small-size pulmonary arteries. The pulmonary arteritis was the only lesion observed in the fetus.     

Environmental urban lead exposure and blood lead levels in children of Mexico City

Lead contamination is now a leading public health problem in Mexico. However, there are few data on the lead content of various environmental sources, and little is known about the contribution of these sources to the total lead exposure in the population of children residing in Mexico City. We conducted a cross-sectional study in a random sample of 200 children younger than 5 years of age who lived in one of two areas of Mexico City. Environmental samples of floor, window, and street dust, paint, soil, water, and glazed ceramics were obtained from the participants' households, as well as blood samples and dirt from the hands of the children. Blood lead levels ranged from 1 to 31 micrograms/dl with a mean of 9.9 micrograms/dl (SD 5.8 micrograms/dl). Forty-four percent of the children 18 months of age or older had blood lead levels exceeding 10 micrograms/dl. The lead content of environmental samples was low, except in glazed ceramic. The major predictors of blood lead levels were the lead content of the glazed ceramics used to prepare children's food, exposure to airborne lead due to vehicular emission, and the lead content of the dirt from the children's hands. We conclude that the major sources of lead exposure in Mexico City could be controlled by adequate public health programs to reinforce the use of unleaded gasoline and to encourage production and use of unleaded cookware instead of lead-glazed ceramics.     

Separation by thermodialysis of acetic acid aqueous solutions

The effect of thermodialysis has been investigated in non-ideal liquid mixtures, employing coarse, unselective porous partitions. For the case investigated — aqueous solutions of acetic acid — the temperature differences applied across the partition induced remarkable separations of the components. This effect may be applicable to the purification of industrial wastes. Furthermore, the investigation of thermodialysis in non-ideal solutions has provided valuable data, aiding to our understanding of the physical basis of the phenomenon.     

Classification of amino acid spin systems using PFG HCC(CO)NH-TOCSY with constant-time aliphatic 13C frequency labeling

We have developed a useful strategy for identifying amino acid spin systems and side-chain carbon resonance assignments in small 15N-, 13C-enriched proteins. Multidimensional constant-time pulsed field gradient (PFG) HCC(CO)NH-TOCSY experiments provide side-chain resonance frequency information and establish connectivities between sequential amino acid spin systems. In PFG HCC(CO)NH-TOCSY experiments recorded with a properly tuned constant-time period for frequency labeling of aliphatic 13C resonances, phases of cross peaks provide information that is useful for identifying spin system types. When combined with 13C chemical shift information, these patterns allow identification of the following spin system types: Gly, Ala, Thr, Val, Leu, Ile, Lys, Arg, Pro, long-type (i.e., Gln, Glu and Met), Ser, and AMX-type (i.e., Asp, Asn, Cys, His, Phe, Trp and Tyr).     

Quasi-Bayesian Behaviour: A more realistic approach to decision making?

Summary In this paper the theoretical and practical implications of dropping-from the basic Bayesian coherence principles- the assumption of comparability of every pair of acts is examined. The resulting theory is shown to be still perfectly coherent and has Bayesian theory as a particular case. In particular we question the need of weakening or ruling out some of the axioms that constitute the coherence principles; what are their practical implications; how this drive to the notion of partial information or partial uncertainty in a certain sense; how this partial information is combined with sample information and how this relates to Bayesian methods. We also point out the relation of this approach to rational behaviour with the more (and apparently unrelated) general notion of domination structures as applied to multicrieria decision making.     

The temporal relationship between emotional distress and cigarette smoking during adolescence and young adulthood.

Empirical evidence regarding the causal nature of the relationship between emotional distress and tobacco use in male and female adolescents provides support for both the distress-to-use and the use-to-distress hypotheses. Using a cross-lagged model with 3 waves of data from 2,961 adolescents followed into young adulthood, the authors tested the hypothesis that this relationship changes over time. As hypothesized, emotional distress in Grade 10 was associated with increased smoking in Grade 12 for both boys and girls. Smoking in Grade 12 was in turn associated with increased emotional distress in young adulthood. The addition of 3 third factors (rebelliousness, deviance, and family problems) to the model did not alter the results. Results suggest that the relationship between tobacco use and emotional distress is a dynamic one in which distress initially leads to use but then becomes exacerbated by it over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)