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Life‐history strategies are known to shift with latitude in many species. While life‐history variation related to body size, reproductive investment, and behavior has been studied for years, another crucial life‐history component is the immune system, which can influence an animal's survival. We measured selected life‐history traits in side‐blotched lizards in southern Utah and Oregon in the field for two consecutive years and conducted a common‐garden experiment in the laboratory to determine how organisms from different latitudes optimize either immunity or reproduction. We observed lizards from southern populations, which are known to be shorter‐lived, had lower immune function during reproduction when compared to northern lizards in 2012, but the relationship reversed in the following year. Our laboratory study revealed that southern lizards healed cutaneous wounds faster and had higher microbiocidal ability when compared to their northern counterparts, but lost mass doing so. The northern lizards ate more than the southern ones and maintained their body mass. It is possible that northern lizards are better adapted to taking advantage of available food resources. Alternatively, southern lizards may have exhibited sickness behavior in response to an immune challenge or reacted more strongly to the stress of captivity. We found differences in life‐history strategies used by animals from different latitudes, and that these changes can shift within a population depending on the weather conditions of the year. Furthermore, when taken from the field and placed into a common‐garden environment, some of these differences in strategy appear to be intrinsic to the animals (i.e., whether they came from southern or northern populations).

Low-grade endometrial stromal sarcoma (LGESS) is a rare malignant uterine tumor with the potential to metastasize years after the primary resection. There is a broad differential diagnosis for endometrial stromal sarcomas (ESS), including both benign and malignant entities. Herein, we present the case of a 64-year-old female with metastatic LGESS to the lung, diagnosed by cytology, 24 years after her initial presentation. This report discusses the cytomorphologic and histopathologic characteristics, and ancillary studies including immunohistochemical stains and recent advances in molecular diagnostics of ESS. Accurate diagnosis of spindle cell lesions in the lung can be challenging. As such, this case highlights the instrumental role of ancillary testing and molecular diagnostics to achieve a more definitive diagnosis.

A myxozoan parasite, Myxobolus inornatus, is one disease agent identified in young of the year (YOY) smallmouth bass in the Susquehanna River Basin, Pennsylvania. We investigated spatial and temporal variability in M. Inornatus prevalence across the Susquehanna River Basin and at several out-of-basin sites. We examined potential land use drivers of M. Inornatus prevalence including agricultural and developed land use. In 1,267 YOY smallmouth bass collected from 32 sites during 2013-2016, M. Inornatus was documented in 43.6% of samples. Among-site variability in parasite prevalence was greater than among-year variability. The effect of agricultural land use on M. Inornatus prevalence had a high probability of being positively correlated at multiple spatial scales (probability of positive effect > 0.80). The effect of developed land use on M. Inornatus prevalence had a relatively high probability of being negatively correlated at multiple spatial scales (probability of negative effect > 0.70). Our results suggest that land use practices could be related to M. Inornatus infection of smallmouth bass. Further study will be necessary to determine whether disease dynamics are a consequence of effects on the host, alterations of instream habitat mediating invertebrate host dynamics and/or survival and dispersal of the parasite infective stage.

Assessing the health and condition of animals in their natural environment can be problematic. Many physiological metrics, including immunity, are highly influenced by specific context and recent events to which researchers may be unaware. Thus, using a multifaceted physiological approach and a context-specific analysis encompassing multiple time scales can be highly informative. Ecoimmunological tools in particular can provide important indications to the health of animals in the wild. We collected blood and hair samples from free-ranging polar bears (Ursus maritimus) in the southern Beaufort Sea and examined the influence of sex, age, and reproductive status on metrics of immunity, stress, and body condition during 2013-2015. We examined metrics of innate immunity (bactericidal ability and lysis) and stress (hair cortisol, reactive oxygen species, and oxidative barrier), in relation to indices of body condition considered to be short term (urea to creatinine ratio; UC ratio) and long term (storage energy and body mass index). We found the factors of sex, age, and reproductive status of the bear were critical for interpreting different physiological metrics. Additionally, the metrics of body condition were important predictors for stress indicators. Finally, many of these metrics differed between years, illustrating the need to examine populations on a longer time scale. Taken together, this study demonstrates the complex relationship between multiple facets of physiology and how interpretation requires us to examine individuals within a specific context.

While the use of nanoparticles has dramatically increased in recent years, the ecological consequences are not well known. In particular, little research has been done to investigate the potentially detrimental effects of nanoparticles on amphibians, especially across all life-history stages of salamanders and newts (caudates). To address this dearth in knowledge, we examined the effects of zinc oxide (ZnO) nanoparticles on egg, larval, and adult Rough-skinned Newts (Taricha granulosa). Chronic toxicity was tested on eggs and larvae, and acute toxicity was tested on eggs, larvae, and adults. For eggs, chronic exposure to ZnO nanoparticles caused higher mortality at 10.0 and 100.0 mg L(-1) compared to 0.0, 0.1, and 1.0 mg L(-1) . When given an acute exposure (24 hr) to 10.0 mg L(-1) nanoparticles at a late developmental stage, larvae hatched 5 days early, at a decreased developmental stage, and smaller size compared to the control. Chronic and acute exposure of larvae increased mortality up to 75% at both 10.0 and 100.0 mg L(-1) and exhibited sublethal effects, most dramatically, severe gill degradation. These results suggest nanoparticles can have lethal and sublethal effects on all life stages of amphibians.

Summary Glucocorticoids are important mediators of energy utilization for key physiological processes, including immune function. Much work has focused on the effects of energy limitation and stress for key physiological processes such as reproduction and immunity. However, it is unclear how stress alters energy use across different energy states, and the physiological ramifications of such effects are even less clear. In this study, we altered energy and stress states of an infrequent feeder, the terrestrial gartersnake (Thamnophis elegans), using fasting and repeated restraint stress (chronic stressors) to test how these challenges interacted to affect immune function, energy metabolites and glucocorticoid reactivity (a traditional indicator of stress state) to restraint stress, a standardized, acute stressor. After this acute stressor, the snakes which had received chronic stress had increased glucocorticoid reactivity, and both treatments altered energy metabolite use and storage. Evidence of interaction of food restriction and chronic stress treatments on innate immune function and energy metabolites (triglycerides and glycerol) suggests that stress alters energy use in a manner dependent on the energy state of the animal. Snakes have a remarkable ability to maintain functionality of key physiological processes under stressful conditions but are still susceptible to multiple simultaneous stressors, a situation increasingly prevalent in our ever-changing environment.

SUMMARY Transient exposure to elevated temperature (37-40 °C) inhibited N2 fixation (acetylene reduction) in cultures of the heterocystous cyanobacterium Anabaena cylindrica (Lemmermann) ATCC 27899 and the unicellular, non-heterocystous cyanobacterium Gloeothece sp. (Nageli) ATCC 27152. In neither organism was inhibition of N2 fixation due to thermal inactivation of nitrogenase. Rather, inactivation of N2 fixation at elevated temperature was a consequence of increased sensitivity to inhibition by O2 In A. cylindrica, thermally induced inactivation of N2 fixation by O2 could be correlated with inhibition of uptake hydrogenase. However, in Gloeothece, inhibition of carbon-supported respiratory O2 consumption by elevated temperature was the probable cause of the increased sensitivity of N2 fixation to O2.

The Cl and ClO quantum yields from the photodissociation of Cl2O have been measured at 320, 360, 400, and 440 nm with the use of chemical ionization mass spectrometry (CIMS). All yields were measur...

The cyanobacterium Anabaena cylindrica can adapt to protect its nitrogenase activity against greater than atmospheric (up to 100%) oxygen tension. The adaptation is light-dependent and involves induction of superoxide dismutase and catalase. After adaptation, the cells are resistant to photooxidation as measured by phycocyanin release and microscopic examination.

A method for the subcellular fractionation of rat liver using whole homogenates of rat liver and analytical sucrose density gradient centrifugation is presented. The distributions in the sucrose gradients of marker enzymes for all organelles have been determined for control homogenates and for homogenates prepared in the presence of selective membrane perturbants. This technique is not subject to potential loss of information inherent in the use of postnuclear supernatants as starting material for fractionation experiments. Particular attention has been paid to the distributions of putative plasma membrane marker enzymes, up to 50% of which may be found in the nuclear pellet. Gamma-Glutamyltransferase has been found to be entirely plasma membrane in location but has a different distribution pattern when compared with other plasma membrane markers. Particulate alkaline phosphatase and alkaline phosphodiesterase are shown to have bimodal distribution, one peak of which is coincident with 5'-nucleotidase. The other peak is coincident with that of the golgi marker, galactosyltransferase, but the membrane structure containing these activities shows characteristics of plasma membrane rather than golgi apparatus.

The cyanobacterium Anabaena cylindrica B629 was suspended in small glass beads and incubated in a gas-tight glass vessel outdoors under a gas atmosphere comprising carbon monoxide (0.2%), acetylene (5%), oxygen (6.5%), and nitrogen. The solution phase initially contained sodium bicarbonate (10mM) at pH 7. Under these conditions the organism continuously produced hydrogen gas for over three weeks. The temperature of the culture was maintained below 30 /degree/C and the minimum night temperatures were recorded. The vessel was covered by a shadecloth, which reduced the natural illumination by approximately 70%. The system is an alternative to those requiring the strict absence of oxygen and little nitrogen, and requires virtually no attention during the incubation period. 18 refs.