Evidence Of Individual Variation Research Articles

Opioid Withdrawal is Not the Same: Evidence of Individual Variation in Opioid Withdrawal Symptomatology

Opioid Withdrawal is Not the Same: Evidence of Individual Variation in Opioid Withdrawal Symptomatology

Dairy Cattle Response to a Virtual Fence When Pasture on Offer Is Restricted to the Post-grazing Residual

Pasture-based dairy systems rely on the accurate allocation of pasture to both meet livestock requirements and maintain the growth of herbage. Currently, physical fences are used to contain livestock however they can be labor-intensive to shift and maintain. Alternatively, virtual fence (VF) systems offer flexibility and real-time control of livestock location. Pre-commercial neckbands (eShepherd®, Agersens, Melbourne, VIC) emit a warning audio tone (AT) when a cow approaches a VF boundary, paired with an electrical pulse (EP) if the cow continues forward into the exclusion zone (EZ). However, the ability of VF technology to control animal location when pasture is restricted to the previous day's residual, remains unknown. Ten non-lactating Holstein-Friesian dairy cows were trained to use a VF system for 6 days before strip grazing a 1.2 ha paddock of annual ryegrass. Over 10 days the cows grazed eight pasture allocations at a pre-grazing pasture mass of 2,324 ± 81 kg DM/ha (mean ± SE) and post-grazing pasture-mass (post-grazing residual) of 1,649 ± 48 kg/DM/ha with a front VF. The allocations had a physical backing fence that included the fresh allocation and a small area of residual to cater for any GPS drift of the front VF. On each day, with the exception of days 5 and 10, the VF was moved forward, and the cows were provided a new pasture allocation. On days 5 and 10, the VF was not shifted, and cows were only offered the previous allocation's residual pasture. The location of each animal (inclusion, buffer, and exclusion zones) and number of stimuli (AT and EP) delivered were recorded. The number of stimuli delivered between the grazing and hold-off days was similar. Cows spent 89% of time within the inclusion zone (IZ), with significant peaks observed on day 5 and 10. Distance that cows traveled into the EZ reduced across time. There was also evidence of individual variation in the number of stimuli and thus time spent in each zone. Overall, the VF system was successful in containing the dairy cows during strip grazing even when only offered the previous days post-grazing residual.

Individual-based acoustic variation of the alarm calls in the long-tailed ground squirrel.

Based on their phylogenetic position, Nearctic ground squirrels are closest relatives to the long-tailed ground squirrel Urocitellus undulates even though it has Palaearctic distribution. We aimed to investigate the variability of alarm calls of the long-tailed ground squirrel to test the individual variation in alarm calls. This species is known to produce two types of alarm calls: whistle alarms and wideband calls. Although ground squirrels are a model group for the study of vocal individuality, this phenomenon has not yet been studied in a species producing two such completely different types of alarms. Most of ground squirrel species produce either whistle or wideband alarms and this species represents a unique model for testing the degree of individual variability depending on completely different acoustic structures. We analysed 269 whistle alarms produced by 13 individuals and 591 wideband alarms from 25 individuals at the western part of Lake Baikal. A discriminant function analysis (DFA) assigned 93.5% (88.9%, cross-validated result) of whistle alarms to the correct individual and 91.4% (84%) of wideband alarms. This is the first evidence of individual variation in wideband alarms compared with whistle alarms and occurrence of vocal individuality in two warning signals of a completely different acoustic structure produced by a ground squirrel.

Abstract P121: Metabolic Influences Of Bisphenol F Exposure In Population-based Heterogeneous Stock Rats

Bisphenol F (BPF) is marketed as a ‘safe’ substitute for bisphenol A (BPA), an endocrine disruptor associated with obesity and heart disease (i.e. cardiometabolic disease), in manufacturing polycarbonates and common consumer products. BPF’s environmental presence is growing and is detected in 66.5% of U.S. adults. Evidence of individual variation in bisphenol levels suggests that gene x environment (GxE) interactions influence cardiometabolic disease risk from bisphenol exposure. Few studies of BPF exposure in either humans or animals have been performed, thus health risks associated with BPF exposure are unknown. Traditional in vivo toxicity studies are performed in isogenic or genetically undefined outbred rodents, leading to conflicting results possibly due to GxE interactions. The N/NIH Heterogeneous Stock (HS) rats are a genetically heterogeneous population amenable to genetic study. Our overall study hypothesis is that BPF-induced cardiometabolic disease has underlying genetic risk, which can be identified using the HS rat model. The goal of this pilot project was to determine if BPF exposure affects growth and adiposity in HS rats. Weanling littermate pairs of male HS rats were randomly exposed to either vehicle (0.1% EtOH) or 1.125 mg BPF/L in 0.1% EtOH for five weeks in drinking water. Cardiometabolic measures, tissues, urine, and feces were taken. Our studies determined BPF exposure in HS rats significantly increases body growth (154.2 ± 3.0 g vs 160.9 ± 3.2 g, p=0.03). BPF exposure alters body composition seen in nuclear magnetic resonance measurements by increasing %fat (7.8 ± 0.3 % vs 8.4 ± 0.3 %; p=0.06), mirroring the significant increase in gonadal white adipose tissue (GWAT) mass (7.58 ± 0.29 mg/g vs 8.37 ± 0.34 mg/g, p=0.01) and perirenal white adipose tissue mass (10.6 ± 0.5 mg/g vs 12.2 ± 0.5 mg/g, p<0.01) in BPF-exposed males. Linear regressions of liver Ugt1a9 expression, an enzyme implicated in BPF metabolism, and %fat or GWAT mass were significantly different between exposure groups (%fat p=0.02, GWAT p=0.02), suggesting that Ugt1a9 expression is related to adiposity phenotype development in BPF-exposed rats. Our data suggest that BPF exposure increases body growth and adiposity, which are risk factors for cardiometabolic disease.

A carbohydrate-active enzyme (CAZy) profile links successful metabolic specialization of Prevotella to its abundance in gut microbiota

Gut microbiota participates in diverse metabolic and homeostatic functions related to health and well-being. Its composition varies between individuals, and depends on factors related to host and microbial communities, which need to adapt to utilize various nutrients present in gut environment. We profiled fecal microbiota in 63 healthy adult individuals using metaproteomics, and focused on microbial CAZy (carbohydrate-active) enzymes involved in glycan foraging. We identified two distinct CAZy profiles, one with many Bacteroides-derived CAZy in more than one-third of subjects (n = 25), and it associated with high abundance of Bacteroides in most subjects. In a smaller subset of donors (n = 8) with dietary parameters similar to others, microbiota showed intense expression of Prevotella-derived CAZy including exo-beta-(1,4)-xylanase, xylan-1,4-beta-xylosidase, alpha-l-arabinofuranosidase and several other CAZy belonging to glycosyl hydrolase families involved in digestion of complex plant-derived polysaccharides. This associated invariably with high abundance of Prevotella in gut microbiota, while in subjects with lower abundance of Prevotella, microbiota showed no Prevotella-derived CAZy. Identification of Bacteroides- and Prevotella-derived CAZy in microbiota proteome and their association with differences in microbiota composition are in evidence of individual variation in metabolic specialization of gut microbes affecting their colonizing competence.

Metabolic Effects of Maternal Bisphenol F Exposure in Population‐based Heterogeneous Stock Rats

Bisphenol F (BPF) is marketed as a ‘safe’ substitute for bisphenol A (BPA), a risk factor for obesity and heart disease, in manufacturing polycarbonates and in common consumer products. BPF’s environmental presence is growing rapidly and is detected in 66.5% of U.S. adults. There is evidence of individual variation in bisphenol levels, suggesting that gene x environment (GxE) interactions influence risk of cardiometabolic disease from bisphenol exposure. Few studies of BPF exposure in either humans or animals have been performed, thus their associated health risks are mostly unknown. Traditional in vivo toxicity studies are performed in genetically undefined outbred rats or genetically homogeneous inbred mice, leading to conflicting results possibly due to GxE interactions. The N/NIH Heterogeneous Stock (HS) rats are outbred rats that better model humans yet are amenable to genetic study. Our overall hypothesis is that BPF exposure is a cardiometabolic disease risk factor based on underlying genetic susceptibility, which can be identified using the HS rat model.We previously demonstrated that five weeks of post‐wean BPF exposure significantly impacts body growth and adiposity in male HS rats. The goal of this project was to determine if maternal BPF exposure also influences growth and adiposity in HS rats, since maternal exposure to BPA is known to impact the metabolic health of both the mother and offspring. HS female breeders were randomly selected for exposure to either vehicle (0.1% Ethanol), 0.1125 mg/L BPF in 0.1% Ethanol (Low Dose), or 1.125 mg/L BPF in 0.1% Ethanol (High Dose) in drinking water during gestation and lactation (~6 weeks total exposure time). One pup of each sex was weaned at 3 weeks of age with no additional exposure. Tissues were taken from dams. Weight and adiposity measures were obtained from weanlings until 8 weeks of age.Our study determined that dams exposed to High Dose showed significantly increased gonadal white adipose tissue (GWAT) mass and trended increased brown adipose tissue (BAT) mass (Table 1). Maternal High Dose exposure impacted weanling body composition at 7 weeks of age as measured by nuclear magnetic resonance (NMR), with the female weanlings significantly increasing %fat mass and trending decreased %lean mass. Maternal BPF exposure also impacted weanling BAT mass, with High Dose female weanlings trending increased BAT mass. No differences were found in male offspring. Our preliminary data suggest that maternal BPF exposure alters adiposity of both the HS dams and female offspring. This work supports BPF exposure as a cardiometabolic disease risk factor and indicates that the HS rat will be a useful model for dissecting GxBPF interactions on metabolic health.Support or Funding InformationNIH P30 ES005605, National Institutes of Health Predoctoral Training Grant T32GM008629 Subject Phenotype Vehicle Low Dose High Dose Dam % BAT (mg) 313 ± 14 343 ± 20 370 ± 31 GWAT (g) 5.7 ± 0.4 5.3 ± 0.5 7.9 ± 0.8 * Female Weanling # Fat % 9.9 ± 1.1 14.0 ± 2.9 17.0 ± 2.0 * Lean % 73.0 ± 1.1 69.3 ± 2.6 66.4 ± 1.7 BAT (mg) 175 ± 9 180 ± 10 213.8 ± 23 Values: mean ± SEM %Vehicle n = 10, Low Dose n = 9, High Dose n = 5 #Vehicle n = 10, Low Dose n = 10, High Dose n = 8 (NMR Vehicle n = 8, Low Dose n = 6, High Dose n = 4) *p < 0.05 High Dose vs Vehicle (linear mixed model regression, Likelihood Ratio Test)

Metabolic Influences of Bisphenol F Exposure in Population‐based Heterogeneous Stock Rats

Bisphenol F (BPF) is marketed as a ‘safe’ substitute for bisphenol A (BPA), an endocrine disruptor associated with obesity and heart disease (i.e. cardiometabolic disease), in manufacturing polycarbonates and in common consumer products (e.g. food packaging). BPF's environmental presence is growing rapidly and is detected in over 85% of U.S. adults and children. There is evidence of individual variation in bisphenol levels, suggesting that genetic variation or gene x environment (GxE) interactions influence risk of cardiometabolic disease due to bisphenol exposure.Characterizing the cardiometabolic effects of BPF in either humans or an animal model has not been performed, and the health risks associated with BPF exposure are vastly unknown. Traditional in vivo toxicity studies are performed in genetically undefined, outbred rats or genetically homogeneous, inbred mice, leading to conflicting results possibly due to GxE interactions. The N/NIH Heterogeneous Stock (HS) rats are a genetically heterogeneous rat population that is amenable to genetic study. The overall hypothesis of this project is that BPF‐induced cardiometabolic disease is based on underlying genetic susceptibility which can be identified using the HS rat model.The goal of this pilot project was to determine if BPF exposure influences growth and adiposity in HS rats. Weanling littermate pairs of male HS rats were randomly selected for exposure to either vehicle (0.1% Ethanol) or 1.125 mg/L BPF in 0.1% Ethanol (average dose 154 μg BPF/kg body weight/day) for five weeks in drinking water. Cardiometabolic measures, tissues, urine, and feces were taken.Our studies determined BPF treatment in HS rats significantly increases body growth (Table 1). Heritability estimates of gain in body weight at eight weeks of age were 0.90±0.13 for vehicle‐treated males and 0.67±0.25 for BPF‐treated males (median±SEM). BPF treatment alters body composition seen in nuclear magnetic resonance (NMR) measurements by increasing % fat and decreasing % lean, mirroring the increase in gonadal white adipose tissue (GWAT) mass and the significant increase in perirenal white adipose tissue (PWAT) mass in BPF‐treated males at eight weeks of age (Table 1). Our data suggest that BPF treatment increases body growth and adiposity, which are risk factors for cardiometabolic disease. Future studies will determine if the response to BPF is genetically regulated.Support or Funding InformationUniversity of Iowa Environmental Health Sciences Research Center (NIH P30 ES005605); National Institutes of Health Predoctoral Training Grant T32GM008629, PI Daniel Eberl.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Dynamic assessment of human sperm DNA damage II: the effect of sperm concentration adjustment during processing.

To evaluate the effect of sperm concentration adjustment in human ejaculates on the sperm DNA quality and longevity. Semen samples were obtained from 30 donors with a normal spermiogram. Following centrifugation, the sperm pellet was resuspended in PBS, and the sperm concentration adjusted to 200, 100, 50, 25, 12, and 6 × 106/mL. Each set of samples was incubated at 37°C for 24h, and the sperm DNA damage was assessed using the chromatin-dispersion test following 0h, 2h, 6h, and 24h of incubation. Sperm DNA fragmentation (SDF) did not differ between the selected experimental conditions at T0; however, Kaplan-Meier estimates for survival showed significant differences with respect to the dilution and time (all P values were smaller than .001). DNA fragmentation in semen samples adjusted to 200 × 106/mL was approximately 3.3 times higher when compared to samples containing 25 × 106/mL and 3.9 higher in comparison with samples adjusted to 12 × 106/mL following 2h of in vitro incubation. Although there was evidence of individual variation in SDF during the incubation period, the general finding was that lower sperm concentrations resulted in a slower rate of DNA fragmentation. Incubation of spermatozoa for ART purposes should be done following a concentration adjustment below 25 × 106/mL in order to avoid a higher susceptibility of the sperm DNA molecule towards fragmentation.

Inner reading voices: An overlooked form of inner speech

Inner speech is theorized to be the basis for auditory verbal hallucinations (AVHs), but few empirical studies have examined the phenomenology of inner speech, particularly while reading. One hundred and sixty posts from a popular question and answer community website were analyzed using a qualitative content analysis approach, to examine the phenomenology of inner reading voices (IRVs). Results indicated that many individuals report routinely experiencing IRVs, which often have the auditory qualities of overt speech, such as recognizable identity, gender, pitch, loudness and emotional tone. IRVs were sometimes identified as the readers’ own voices, and sometimes as the voices of other people. Some individuals reported that IRVs were continuous with audible thoughts. Both controllable and uncontrollable IRVs were reported. IRVs may provide evidence for individual variation in imagery vividness and support for inner speech accounts of AVHs. IRVs may be a useful model for studying AVHs in the non-clinical population and need further investigation.

Longitudinal bio-logging reveals interplay between extrinsic and intrinsic carry-over effects in a long-lived vertebrate.

Carry-over effects have major implications for individual fitness and population and evolutionary dynamics. The strength of these effects is dependent on an individual's intrinsic performance and the environmental conditions it experiences. However, understanding the relative importance of environmental and intrinsic effects underpinning seasonal interactions has proved extremely challenging, since they covary. A powerful approach is longitudinal measurement of individuals across a range of conditions, whereby each animal is effectively acting as its own control. We related time spent foraging during the nonbreeding period to subsequent breeding performance in European Shags Phalacrocorax aristotelis. By following individuals for up to six years, we could test simultaneously for extrinsic and intrinsic effects using random regression modeling. We detected significant annual and among-individual variation in daily foraging time during the late winter, and clear variation among individuals in the quadratic relationship between foraging time and date. Shorter foraging times were associated with earlier and more successful breeding, driven by differences among years and individuals, with no evidence of individual variation in the slope of these relationships. That both environmental and intrinsic variation shape carry-over effects has important implications for population responses to environmental change.

Nurses’ aims when managing pediatric postoperative pain: Is what they say the same as what they do?

The purpose of this study was to explore nurses' aims when managing postoperative pain and whether reported aims reflect actual practices. Participant observation was used to collect data regarding nurses' (n = 17) pain management practices. Nurses (n = 19) were asked: When managing postoperative pain, what is your overall aim? Around half the participants (n = 10) aimed for patients to be comfortable while others aimed for a pain score of 2-3 (n = 7), or below 5 (n = 2). Observed practices matched aims for just more than half the participants (n = 9). There is evidence of individual variation in practices. This may impact on the care provided.

Acoustic Repertoire of the Philippine Tarsier (Tarsius syrichta fraterculus) and Individual Variation of Long-Distance Calls

We present the spectrographic description of the vocal repertoire of the Philippine tarsier (Tarsius syrichta fraterculus), a solitary living nocturnal primate for which a very limited information about acoustic communication exists to date. The majority of vocalizations were performed around sunset and, less frequently, at sunrise. We identified eight call types. Five calls recorded during communication between adults included three long-distance calls—loud call, smack-whistle, and whistle—then a soft locust-like chirp and a bird-like trill. Two other calls—cheep and twitter—were recorded during mother-infant communication. One distress call was emitted by adults during handling. All calls were performed in the 9752 Hz to more than 22 kHz frequency range. This study provides the first evidence of individual variation in the long-distance calls performed by tarsiers. Moreover, our study provides a basis for future comparison within as well as between tarsier species taxonomy. Bioacoustic methods can be used in monitoring of these cryptic species and determining their distribution range. Thus, bioacoustic studies can help to improve conservation strategies of different population/species.

Genetic adaptation to extreme hypoxia:: Study of high-altitude pulmonary edema in a three-generation Han Chinese family

Organismal response to hypoxia is essential for critical regulation of erythropoiesis, other physiological functions, and survival. There is evidence of individual variation in response to hypoxia as some but not all of the affected individuals develop polycythemia, and or pulmonary and cerebral edema. A significant population difference in response to hypoxia exist as many highland Tibetan, Ethiopian, and Andean natives developed adaptive mechanisms to extreme hypoxia. A proportion of non-adapted individuals exposed to high altitude develop pulmonary edema (HAPE), pulmonary hypertension, cerebral edema, and extreme polycythemia. The isolation of causative gene(s) responsible for HAPE and other extreme hypoxia complications would provide a rational basis for specific targeted therapy of HAPE, allow its targeted prevention for at-risk populations, and clarify the pathophysiology of other hypoxic maladaptations. The only suggested genetic linkage among unrelated individuals with HAPE has been with endothelial nitric oxide synthase ( eNOS) gene. Here we describe a family with multiple members affected with HAPE in three generations. Families with multiple affected members with HAPE have not been described. We first ruled out linkage of HAPE with the eNOS gene. We then performed an analysis of the whole genome using high-density SNP arrays (Affymetrix v5.0) and, assuming a single gene causation of HAPE, ruled out linkage with 34 other candidate genes. Only the HIF2A haplotype was shared by individuals who exhibit the HAPE phenotype, and work on its possible causative role in HAPE is in progress. The small size of our family does not provide sufficient power for a conclusive analysis of linkage. We hope that collaboration with other investigators with access to more HAPE patients will lead to the identification of gene(s) responsible for HAPE and possibly other maladaptive hypoxic complications.

The influence of exogenous steroid hormones on steroid receptors, uterine histological structure and the bacterial flora of the normal bitch.

Oestrogen (ER) and progesterone (PR) receptors have been shown to vary in both concentration and distribution during the oestrous cycle of the bitch, influenced by the normal changes in endogenous reproductive hormones. The influence of exogenous steroid hormones on steroid receptors and the histological structure of the uterus was studied in two groups of parous Beagle bitches. Group A (n = 6) were treated with progesterone (P4) in oil i.m. (3 mg/kg) in late metoestrus on the day that peripheral plasma P4 concentrations were first identified as <10 ng/ml, and subsequently once weekly on three other occasions. Group B (n = 6) were treated with a single i.m. injection of MPA (50 mg, 4.2-5.6 mg/kg) following the same protocol. Full-thickness uterine wall biopsies were obtained from the mid part of one horn 2-7 days after the last (fourth) injection of P4 or MPA. During the subsequent oestrus, when peripheral plasma P4 concentrations were between 8 and 10 ng/ml, each bitch in both groups (n = 12) received a single injection of oestradiol benzoate (ODB) in oil i.m. (7.5 mg, 0.63-0.84 mg/kg). All bitches had an ovariohysterectomy 7 days later. Full-thickness uterine wall samples were obtained from the mid part of the intact horn and other parts of the uterus. Swabs were taken from the uterine lumen for bacteriological examination; all were sterile. Tissue samples were sectioned and examined for evidence of lesions, and stained for ER and PR receptors using an immunocytochemical method. The immunoreactivity was scored semiquantitatively, incorporating both the intensity and distribution of specific staining of the receptors using a simplified histoscore (H-score). At the time of ovariohysterectomy, fluid had accumulated in the isolated section of the uterine horn distal to the point of biopsy; the volume was greater in the MPA-treated bitches. There was also evidence in some sections of histological changes in the endometrium. Variations in the expression of both ER and PR were seen between bitches, which may have been due to some not being in mid-metoestrus at the time of treatment. In general, ER scores were low after P4 and MPA treatment, but following ODB there was a significant (P<0.05) increase in ER expression in all parts of the endometrium. PR scores were zero in the glandular epithelium of all 12 bitches after P4, MPA and ODB treatment, whereas in the other parts of the endometrium they were generally moderate to high. Following treatment with ODB, PR generally increased in the three regions of the endometrium where PR were present. The study shows that ER and PR distribution and expression in the endometrium of bitches can be modified by P4, MPA and ODB, with evidence of individual variation.

Perch Height Selection by Juvenile Sceloporus Lizards: Interspecific Differences and Relationship to Habitat Use

Perch height selection was studied in juvenile western fence lizards (Sceloporus occidentalis) and sagebrush lizards (Sceloporus graciosus) in the field and in the laboratory. In nature juvenile S. occidentalis were more arboreal than were juvenile S. graciosus. In laboratory experiments with lab-reared 3-4 wk old lizards, S. occidentalis perched off the ground more frequently. Differences between these two species in habitat preference are inferred to be at least partly innate, and emerge at an early age. Within each species, juveniles from different field populations differed in habitat use in the wild: lizards were more terrestrial at higher elevations. However, lab-reared juveniles from different populations of each species did not differ in laboratory tests of perch selection. In S. occidentalis there was evidence of individual variation in perch selection in the laboratory, but no among-family variation was detected.