HYPERPARATHYROIDISM

Because of the variable and vague clinical symptoms of the disease, diagnosis of hyperparathyroidism may be missed or delayed.Presenting symptoms and findings may be localized to the urological system or to the skeletal framework, with indications of abnormal blood calcium levels.In any case in which the patient''s only complaints are malaise, lassitude, or progressive weakness, and in which routine laboratory findings are inconclusive, the blood calcium level should be determined.While not in itself diagnostic, a high level of calcium in the blood will lead to further investigation such as skeletal x-ray studies and blood phosphorus and serum alkaline phosphatase determinations.Vigilance postoperatively to forestall tetany is of great importance.     

Differential allocation of male-derived nutrients in two lampyrid beetles with contrasting life-history characteristics

Across diverse animal taxa, sperm is transferred from malesto females during mating within a spermatophore produced bymale accessory glands. In some insects, male spermatophoresprovide females with nutrients that may be used to increasereproductive output or for somatic maintenance, while in othersno such benefits have been detected. Boggs suggested that variationin the current function of spermatophores may be explained byconsidering ecological and life-history factors. This studyexamined spermatophore function in Ellychnia corrusca and Photinusignitus (Coleoptera: Lampyridae), two beetles that exhibit markeddifferences in adult diet, adult life span, and overwinteringstage. During mating, males of both species transfer to femalesa complex, proteinaceous spermatophore, which is subsequentlydigested in a specialized sac within the female reproductive tract.Males of each species were injected with ³H-radiolabeled aminoacid mixtures and mated with conspecific females. The fate of spermatophore-derivedproteins was determined by dissecting females at various timesafter mating with these radiolabeled males. Females of thesetwo species showed markedly different patterns of incorporationof spermatophorederived nutrients. P. ignitus females incorporatedthe majority (62%) of spermatophore-derived protein into maturingoocytes within 2 days after mating. In contrast, in E. corruscaa large percentage of radiolabel (46%) appeared in female fatbody at 6 days after mating, with a threefold lower allocationto maturing oocytes compared to P. ignitus. These findings supportthe prediction that short-lived, nonfeeding females are selectedto allocate a greater proportion of male-derived nutrients toreproduction, while longer-lived, feeding females are selectedto allocate a greater proportion to somatic reserves and maintenance.These results suggest that life-history characteristics maybe useful in explaining observed differences in spermatophorefunction across taxa.     

Identification of homoeologous chromosomes in hexaploid oat (A. byzantina cv Kanota) using monosomics and RFLP analysis

The use of RFLP markers, together with a partial set of monosomics available in Avena byzantina cv Kanota, has enabled us to identify putative homoeologous chromosome sets in hexaploid Avena species (2n = 6x = 42, AACCDD). We first identified probes producing distinct three-band patterns on Southern blots that possibly reflect orthologous loci of the three genomes present in the hexaploid. Using monosomic analysis, 51 different restriction fragments that hybridized to 26 probes were localized to 12 different chromosomes for which monosomic stocks were available. These DNA restriction fragments were localized to specific monosomics using image analysis to quantify band intensity relative to other bands in the same lane. From these data, we have tentatively identified two complete homoeologous sets of three chromosomes each and two partial sets of two of the three chromosomes. The results indicate that RFLP dosage analysis is useful in the characterization of homoeologous chromosomes in hexaploid oat where nullisomics for many of the chromosomes are not available.Mention of a trademark or proprietary product does not constitute a guarantee or warranty by the USDA-ARS or the University of Minnesota and does not imply approval over other products that also may be suitableJoint contribution of the Minnesota Agricultural Experiment Station and USDA-ARS. Scientific Journal Series Paper no. 20 650 of the Minnesota Agricultural Experiment Station     

A sedimentary record of the evolution of the global marine phosphorus cycle

Phosphorus (P) is typically considered to be the ultimate limiting nutrient for Earth's biosphere on geologic timescales. As P is monoisotopic, its sedimentary enrichment can provide some insights into how the marine P cycle has changed through time. A previous compilation of shale P enrichments argued for a significant change in P cycling during the Ediacaran Period (635–541 Ma). Here, using an updated P compilation—with more than twice the number of samples—we bolster the case that there was a significant transition in P cycling moving from the Precambrian into the Phanerozoic. However, our analysis suggests this state change may have occurred earlier than previously suggested. Specifically in the updated database, there is evidence for a transition ~35 million years before the onset of the Sturtian Snowball Earth glaciation in the Visingsö Group, potentially divorcing the climatic upheavals of the Neoproterozoic from changes in the Earth's P cycle. We attribute the transition in Earth's sedimentary P record to the onset of a more modern-like Earth system state characterized by less reducing marine conditions, higher marine P concentrations, and a greater predominance of eukaryotic organisms encompassing both primary producers and consumers. This view is consistent with organic biomarker evidence for a significant eukaryotic contribution to the preserved sedimentary organic matter in this succession and other contemporaneous Tonian marine sedimentary rocks. However, we stress that, even with an expanded dataset, we are likely far from pinpointing exactly when this transition occurred or whether Earth's history is characterized by a single or multiple transitions in the P cycle.     

Rapid evolution of a primate sperm protein: relaxation of functional constraint or positive Darwinian selection?

Protamines are arginine-rich proteins that replace histones and bind sperm DNA during spermatogenesis in vertebrates. Previous studies have shown that protamine exons evolve faster than does the protamine intron. It has been suggested that this is a result of a relaxation of functional constraint. However, a more likely explanation is that the evolutionary rate of exons has been accelerated by positive Darwinian selection, because introns are generally believed to evolve in a neutral fashion. Therefore, we examined the possibility that positive selection has been acting on the protamine genes of three groups of placental mammals: primates (hominoids and Old World monkeys), rodents (mice, rats, and guinea pigs), and pecoran ruminants (deer and bovids). We found that the nucleotide substitution rate at nonsynonymous sites is significantly higher than the rate at synonymous and intron sites for protamine P1 of hominoids and Old World monkeys. This result suggests that positive selection has been operating on protamine P1 of these species. In contrast, no clear-cut evidence of positive selection was found for protamine P1 of ruminants and rodents or protamine P2 of primates. The agent of positive selection on primate protamine P1 remains unknown, though sperm competition is a possibility. Further investigations on the function and intraspecific polymorphism of this protein are needed in order to identify the selection agent.