Evaluating the utility of an accelerometer and urinary hormone analysis as indicators of estrus in a Zoo-housed koala (Phascolarctos cinereus)

Induced ovulators, such as the koala, do not always have overt signs of estrus, which makes pairing these animals for breeding purposes difficult to achieve in a zoo setting. This study examined the possibility of using alternative methods to behavioral sampling and weight fluctuations for monitoring estrus in a female koala of reproductive age. We attempt to gain an improved understanding of koala estrus and enhance our ability to detect it by combining a noninvasive technique for hormone analysis with a newer method for recording activity level. The findings suggest that activity levels were accurately measured using an accelerometer and increased activity was associated with one estrus behavior, bellowing. Weekly weight declines occur with increases in activity registered from the accelerometer. We also validated an assay to detect progesterone and estradiol in female koala urine in an attempt to detect an estrus spike. However, neither urinary concentrations of estradiol nor progesterone was associated with behavioral cues of estrus in our subject. We suggest that increased female activity, bellowing, and weight loss all indicate a pro-estrus state that requires proper male stimulation in order to achieve a full estrus display. Zoo Biol 28:59–68, 2009. ©2008 Wiley-Liss, Inc.     

Erythrocyte pyrimidine 5′-nucleotidase inhibition by acute lead exposure in neonatal rats

Inhibition by lead of erythrocyte pyrimidine 5′-nucleotidase (P5N) is thought to contribute to morphological abnormalities observed in red blood cells (RBC) of lead-exposed subjects. However, neither the mechanism of lead inhibition of P5N nor the relationship of this inhibition to blood lead levels attained in exposed subjects is known. In the present investigation, acute in vivo and in vitro lead acetate effects on erythrocyte P5N from 21-day-old rat pups were determined and were related to blood lead concentrations ascertained by atomic absorption spectrophotometry. Acute lead administration to rat pups resulted in a 16% to 21% reduction in erythrocyte P5N, with mean blood lead levels ranging from 77 to 108 μg/dl 24 hours later. Inhibition of erythrocyte P5N was linearly related to blood lead level (r = ?0.67, P < 0.05) following acute lead administration. Lead acetate addition to RBC preparations from 21-day-old rats resulted in concentration-dependent P5N inhibition which was comparable to that produced following acute in vivo exposure. The results indicate that acute P5N inhibition in lead-treated neonatal rats is due to noncompetitive P5N inhibition by lead. The inhibition of P5N produced by acute lead treatment is linearly related to blood lead concentrations.     

The genetic influence on serum haemolytic complement levels in cattle

Total serum haemolytic complement (HC) activity has been determined in 130 young bulls of the Norwegian Red Cattle Breed (NRF). A highly significant sire effect (p < 0.01) on HC with a corresponding heritability of about 0.75 was estimated. Evidence of any simple mode of inheritance is not produced but the distribution patterns of HC indicate influences of relatively few genes.     

Endangered Cape Sable Seaside Sparrow Survival

ABSTRACT We investigated survival for male, female, and first-year Cape Sable seaside sparrows (Ammodramus maritimus mirabilis, hereafter sparrows), a federally endangered bird restricted to the Florida Everglades, USA. Accurate estimates of survival are critical to improve management decisions and population estimates for this and other threatened species. We used Program MARK to evaluate effects of age, sex, population membership, temporal variation, and ground-water levels on annual survival from mark-recapture data collected across 3 sparrow populations from 1997 to 2007. We found little evidence that annual survival rates differed between the populations or across ground-water levels, but we found high variability between years for both adult and juvenile survival. Our results revealed female sparrows experienced 14–19% lower survival than males. Sparrows experienced much lower survival during their first year of life and were short-lived (2–3 yr). Our results highlight sparrows' susceptibility to population declines and suggest that management actions aimed at increasing survival may be effective for this species' management.     

Elevation in liver enzymes is associated with increased IL-2 and predicts severe outcomes in clinically apparent dengue virus infection

The objective of the present study was to assess the circulating TNF-α and IL-2 levels in dengue virus (DENV) infected patients and to correlate these with clinical severity of DENV infections. A single analyte quantitative immunoassay was used to detect TNF-α and IL-2 in 24 dengue fever (DF) and 43 dengue haemorrhagic fever (DHF) patients, 15 healthy adults and 6 typhoid patients. The mean TNF-α and IL-2 levels of DENV- infected patients were higher than that of healthy adults and typhoid patients. No significant difference in TNF-α levels was noted between DF and DHF patients (p = 0.5) but a significant increase in IL-2 levels was observed in DHF compared with DF patients (mean of DF = 59.7 pg/mL, mean of DHF = 166.9 pg/mL; p = 0.02). No significant association of TNF-α or IL-2 levels was noted with packed cell volume (>45), thrombocytopenia, leucopenia or the presence of viraemia. The liver function tests measuring AST (aspartate aminotransferase) (p = 0.01) and ALT (alanine aminotransferase) (p = 0.02) levels were significantly elevated in DENV-infected patients. AST:ALT was significantly elevated in DHF/DSS (dengue shock syndrome) compared with DF patients. A significant positive linear correlation was noted between AST and IL-2 (r = 0.31; p = 0.01) and ALT and IL-2 elevations (r = 0.2; p = 0.02). Thus, AST and ALT levels correlate with both disease severity and circulating IL-2 levels. We suggest a role for circulating IL-2 in liver dysfunction and propose that a combined assessment of AST/ALT in conjunction with IL-2 at the early stages of symptomatic DENV infection may be useful to predict the severe forms of dengue.     

Enhancing monoclonal antibodies and hybridoma cell lines

We are interested in determining the range of variants present in a cell population that can actually be isolated. We have used subcloning and sublining to search for variants with increased antibody stability, increased cell line stability to freezing and defrosting, increased cell population viability, increased antibody production and the ability to grow in simpler media. This paper presents the case histories of several different hybridoma cell lines which required some property changed before they became production ready clones. We found that switching the class of an antibody from IgG₃ to IgG₁ did increase its stability, decrease its tendency to aggregate and allowed it to be used in a commercial diagnostic kit. We could isolate subclones that produced twice the level of antibody with a frequency of 1–3%. It was straight forward to isolated clones that were stable to freezing and defrosting or grew in a simpler media. We were not successful in increasing the maximum viability of a cell line. In conclusion, we have found that any population of hybridoma cells has natural variants with significantly enhanced properties that can be isolated.     

Integrating effects of contaminants across levels of biological organization: an overview

Effects of contaminants may occur at all levels oforganization, from molecular to ecosystem-levelresponses. While biochemical and physiologicalalterations in organisms may occur rapidly and areoften stressor-specific, the ecological relevance ofthese suborganismal indicators is uncertain.Alterations in populations and communities havegreater ecological relevance, but a firm mechanisticunderstanding of these responses is often lacking.Developing mechanistic linkages across levels ofbiological organization would greatly improve ourunderstanding of how organisms are affected bycontaminants in nature. The papers in this seriespresent several innovative approaches for integratingeffects of contaminants across levels of biologicalorganization. Authors were asked to describe theecological consequences of responses at lower levelsof organization (biochemical, physiological,individual) and to speculate on the underlyingmechanisms associated with population and communityalterations. The most consistent finding of the fivepapers in this series is that there is no singlespatiotemporal scale or level of biologicalorganization at which ecotoxicological investigationsshould be conducted.     

Genetic variants affecting human TRPA1 or TRPM8 structure can be classified in?vitro as ‘well expressed’, ‘poorly expressed’ or ‘salvageable’

Multiple mis-sense variants of TRPA1 (transient receptor potential A1) and TRPM8 (transient receptor potential M8) are recorded in the human genome single nt polymorphism (SNP) database, but their potential impact on channel signalling in patho-physiology is not fully explored. Variants, mostly quite rare in the general human population, alter sites in different structural domains of these homo-tetrameric ion channel proteins. The effects of individual SNPs affecting the large cytoplasmic N-terminal domain have not been completely documented for TRPM8 or TRPA1. We examined the Ca²⁺ signalling properties of a short-list of eight variants affecting the N-terminal domain by individual expression in human embryonic kidney HEK293 or neuroblastoma (SH-SY5Y) cell lines (four SNP variants for TRPM8: G150R, K423N, R475C, R485W and four for TRPA1: Y69C, A366D, E477K, D573A). These were compared with TRPA1 SNP variants affecting intracellular loops located beyond the N-terminal domain and associated with gain of function (such as increased sensitivity to agonists: TRPA1 R797T and N855S). A substitution in TRPA1 (Y69C) exhibited high expression/sensitivity to agonists (high iCa²⁺max (maximum level of intracellular calcium ion), similar to R797T, but less sensitive than N855S), whereas each of the other non-conservative substitutions exhibited poor signalling response (low iCa²⁺max). Responses from these poorly expressed variants could be salvaged, to different extents, by pre-treating cells with the Src (Src protein) family inhibitor protein kinase inhibitor PP2 (PP2: 4-Amino-3-(4-chlorophenyl)-1-(t-butyl)-1H-pyrazolo[3,4-d]pyrimidine, 4-Amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine), or with micromolar Zn²⁺. The TRPA1 variants and several experimental mutants (TRPA1 Y97F, Y226F and YY654–655FF) expressed poorly in SH-SY5Y compared with HEK293 cells. More in-depth studies are needed to identify SNP variants eliciting gain of function in these TRP (transient receptor potential) channels and to assess their roles in medical conditions.