Grazing in sagebrush rangelands in western North America: implications for habitat quality for a sagebrush specialist, the pygmy rabbit

Livestock grazing is one of the primary uses of sagebrush rangelands in western North America; therefore, an understanding of the ecological implications of grazing on habitat quality for sagebrush-dependent wildlife is needed to help land managers balance multiple objectives for land use. We studied effects of cattle grazing on components of habitat for an uncommon sagebrush habitat specialist, the pygmy rabbit (Brachylagus idahoensis), which has been petitioned for endangered or threatened status in the USA. We evaluated multiple components of habitat before and after grazing in replicated control and treatment plots in a mesic, high-elevation sagebrush-steppe environment in south-western Montana, USA. We predicted that grazing would decrease the biomass of herbaceous forage, alter security cover, and increase rate of collapse of rabbit burrows, and we expected that these effects would be more pronounced during summer than spring. As expected, cattle grazing reduced the biomass of perennial grasses available to pygmy rabbits after grazing that occurred during either spring or summer, and the biomass of forbs after spring grazing. In contrast, grazing did not markedly influence the functional properties of vegetation related to predation risk or the integrity of rabbit burrow systems. In the context of the stocking rate of the allotments in our study (7.3 acres/Animal Unit Month, 2.95 ha/Animal Unit Month), annual cattle grazing did not seem to markedly change habitat for pygmy rabbits in our study area; however, longer-term and higher intensity grazing might result in more pronounced habitat changes. Understanding the ecological implications of cattle grazing on habitat quality for pygmy rabbits and other sagebrush-dependent wildlife can guide conservation strategies for these species on sagebrush rangelands managed under multiple-use policies.

Generalized linear models with coarsened covariates: a practical Bayesian approach

Coarsened covariates are a common and sometimes unavoidable phenomenon encountered in statistical modeling. Covariates are coarsened when their values or categories have been grouped. This may be done to protect privacy or to simplify data collection or analysis when researchers are not aware of their drawbacks. Analyses with coarsened covariates based on ad hoc methods can compromise the validity of inferences. One valid method for accounting for a coarsened covariate is to use a marginal likelihood derived by summing or integrating over the unknown realizations of the covariate. However, algorithms for estimation based on this approach can be tedious to program and can be computationally expensive. These are significant obstacles to their use in practice. To overcome these limitations, we show that when expressed as a Bayesian probability model, a generalized linear model with a coarsened covariate can be posed as a tractable missing data problem where the missing data are due to censoring. We also show that this model is amenable to widely available general-purpose software for simulation-based inference for Bayesian probability models, providing researchers a very practical approach for dealing with coarsened covariates.

Effects of genetic management on reproduction, growth, and survival in captive endangered pygmy rabbits (Brachylagus idahoensis)

A quarter of all lagomorph species worldwide are threatened with extinction. Captive breeding programs, such as that developed for the Columbia Basin (CB) pygmy rabbit (Brachylagus idahoensis), sometimes are implemented as emergency conservation measures to restore small, genetically distinct populations. However, small source populations also may have low genetic diversity, which may influence attributes related to fitness, including growth, survival, and reproduction. We used mixed-effects regression models to explore the influence of genetic pedigree (% CB) on pairing success, growth, and survival during the 10-year captive breeding program at Washington State University, which included controlled pairings and outbreeding with pygmy rabbits from Idaho. Pairing success, juvenile growth, and juvenile survival declined with increasing CB pedigree of 1 or both parents, suggesting inbreeding depression among the small number of related founders. Demographic variables such as age, sex, and previous pregnancies, and environmental variables such as month and temperature at birth also were associated with production of pygmy rabbits. Our study illustrates the difficulty of retaining a unique genome of a small source population while simultaneously producing enough rabbits for restoration into natural habitat as part of endangered species recovery programs.

Evaluating DNA degradation rates in faecal pellets of the endangered pygmy rabbit

Noninvasive genetic sampling of faecal pellets can be a valuable method for monitoring rare and cryptic wildlife populations, like the pygmy rabbit (Brachylagus idahoensis). To investigate this method's efficiency for pygmy rabbit monitoring, we evaluated the effect of sample age on DNA degradation in faecal pellets under summer field conditions. We placed 275 samples from known individuals in natural field conditions for 1-60 days and assessed DNA quality by amplifying a 294-base-pair (bp) mitochondrial DNA (mtDNA) locus and five nuclear DNA (nDNA) microsatellite loci (111-221 bp). DNA degradation was influenced by sample age, DNA type, locus length and rabbit sex. Both mtDNA and nDNA exhibited high PCR success rates (94.4%) in samples <1 day old. Success rates for microsatellite loci declined rapidly from 80.0% to 42.7% between days 5 and 7, likely due to increased environmental temperature. Success rates for mtDNA amplification remained higher than nDNA over time, with moderate success (66.7%) at 21 days. Allelic dropout rates were relatively high (17.6% at <1 day) and increased to 100% at 60 days. False allele rates ranged from 0 to 30.0% and increased gradually over time. We recommend collecting samples as fresh as possible for individual identification during summer field conditions. Our study suggests that this method can be useful for future monitoring efforts, including occupancy surveys, individual identification, population estimation, parentage analysis and monitoring of genetic diversity both of a re-introduced population in central Washington and across their range.

Outcomes associated with a negotiated asthma treatment plan

Negotiated treatment plans are increasingly recommended in asthma clinical care. However, limited data are available to indicate whether this more patient-engaged process results in improved health outcomes. The aim of this study was to determine the associations between the presence of a negotiated treatment plan and the outcomes related to adherence to the medical regimen, symptom control, and health care use. The focus of the study was on women, the subgroup of adult patients, who are most vulnerable for negative asthma outcomes. Data were collected by telephone interview and medical record review from 808 women diagnosed with asthma at baseline, first year, and second year follow-up. Associations were examined between the presence of a negotiated treatment plan at baseline and subsequent asthma outcomes. Women with a negotiated treatment plan reported more adherent to prescribed asthma medicines (odds ratio (OR) = 2.41, 95% confidence interval (CI) = (1.82, 3.19)) and those with a plan and using oral steroids at baseline had less oral steroid use at follow-up (OR = 0.21, 95% CI = (0.05, 0.93)). Women with a negotiated plan also had more days (17%, 95% CI = (8, 27)) and nights (31%, 95% CI = (16, 48)) with symptoms than those without such a plan. No differences in hospitalizations, emergency department visits, or urgent physician office visits were noted between the groups. Patients with higher education levels were more likely to have a negotiated treatment plan. Negotiated treatment plans appear to have achieved greater adherence to prescribed asthma medicines and less need for oral steroids but were not related to fewer symptoms of asthma or reductions in urgent health care use. Additional strategies may be needed to reduce symptom and health services utilization outcomes.

A COMPARISON OF TWO TIME INTERVALS FOR THE AUSCULTATED ACCELERATION TEST

OBJECTIVE

Interest in an inexpensive, easy-to-administer antenatal screening test that did not rely on the use of electronic fetal monitoring led to development of the fetoscope administered auscultated acceleration test (AAT) in the late 1980s. More recent efforts have been directed toward providing those who may use the AAT with important information about the most effective and clinically appropriate AAT procedures. The purpose of this study was to determine the screening test validity performance of two AAT time intervals--6 minutes and 10 minutes.

METHODS

Two auscultated acceleration tests (AAT6 and AAT10) were simultaneously performed using different time intervals on 205 women with high-risk pregnancies undergoing simultaneous nonstress tests (NSTS) who were referred to a tertiary care unit for antepartum testing. Standard measurements of screening test validity were calculated for each test in the prediction of selected perinatal outcomes. NST findings were included for comparative purposes.

RESULTS

The AAT6 yielded an overall higher specificity as compared with the AAT10 at the expense of a slightly lower sensitivity for most perinatal outcomes; these differences were not significant at the .05 level. Relative risk ratios were similar for the AAT6 and AAT10 for both fetal distress and neonatal morbidity, with both AAT being a more effective predictor of neonatal morbidity than for fetal distress. Both tests yielded better sensitivity when compared with NST.

CONCLUSIONS

Even though there was a nonsignificant trend toward higher sensitivities and lower specificities for the 10-minute AAT, this study showed that the differences in prediction of perinatal outcomes between the 6-minute and 10-minute AAT were minimal. In view of the added labor required for the 10-minute AAT in the absence of enhanced screening test validity, the 6-minute AAT is clinically preferred. This study has prompted new research questions for the continued development of the AAT as a low-technology fetal assessment technique with potential usefulness by midwives and their colleagues in a variety of settings worldwide.

Abstract B13: High-risk human papillomavirus prevalence in oral and oropharyngeal premalignant lesions: A critical literature review

Introduction: During the past decade, there has been a significant increase in the incidence of human papillomavirus (HPV) related squamous cell cancer of the oropharynx, especially those of the tonsil and tongue base. HPV-16 and HPV-18 have been linked to these malignant neoplasms. Generally, oral epithelium undergoes a sequence of histopathological pre-malignant transformations before the development of invasive carcinoma. A study evaluating the prevalence of HPV-16/18 types in histopathologically diagnosed oral pre-malignant lesions (OPL) is lacking. Therefore, we conducted a comprehensive literature review to estimate the prevalence of HR HPV types in different grades of OPLs.

Study Design: A critical literature search was conducted using Pubmed and SCOPUS databases for the key terms human papillomavirus infection, head and neck cancer, oral cancer, oral hyperplasia, oral dysplasia, and oral leukoplakia. A total of 90 articles related to HPV in oral tissue and pre-malignant lesions were identified. Of these, 29 articles evaluated the prevalence of HPV in histopathological OPLs (hyperplasia and dysplasia). In addition, 11 out of these 29 articles determined the prevalence of HPV in histologically evaluated leukoplakic samples. Only research articles published from 1990 — 2009 were used for this review.

Results: Overall, the 29 articles evaluated high-risk (HR) HPV in 1,171 OPLs. This included 140 hyperplasias, 467 dysplasias, 425 leukoplakic lesions without dysplasia, and 139 leukoplakic lesions with dysplasia. The prevalence of any type of HPV in hyperplasia, dysplasia, leukoplakia without dysplasia, and leukoplakia with dysplasia was 24%, 25%, 28%, and 20% respectively. The prevalence of HR HPV-16/18 in these lesions was 24%, 21%, 26% and 26% respectively. The difference in prevalence of different grades of OPLs was not statistically significant. The prevalence of any HPV type in mild, moderate, and severe dysplastic lesions was 43%, 39%, and 33% respectively. The prevalence of HR HPV-16/18 in mild, moderate, and severe dysplastic lesions was 39%, 32%, and 28% respectively.

Conclusion: High-risk HPV infection has been noted even in early stage histopathological OPLs like hyperplasias and mild dysplasias, and their prevalence rate is very similar to high grade OPLs, and oral (OC) and oropharyngeal cancers (OPC). Larger studies are needed to obtain a more precise estimate of the prevalence and persistence of HR HPV in histopathologically diagnosed OPLs in order to better understand the etiopathogenesis of HPV related OC and OPC.

Citation Information: Cancer Prev Res 2010;3(12 Suppl):B13.

From the female perspective: Long-term effects on quality of life of a program for women with asthma

BACKGROUND

Although, among adults, asthma predominates in women, the role of sex and gender in asthma has only recently been studied. Moreover, only one study has focused on the management of asthma by women, reporting that 1 year subsequent to an intervention addressing sex and gender role factors, women's asthma status was improved.

OBJECTIVE

Data from a 2-year postintervention follow-up were assessed to determine whether there were longer-term effects on the asthma status and quality of life (QoL) of the participants.

METHODS

A randomized controlled design was used in which female patients with asthma, who were receiving services at the University of Michigan Health System, Ann Arbor, Michigan (2002-2006), were assigned to either a control group or a female-oriented intervention group that focused on management challenges related to sex and gender role factors. Data were collected at baseline and 2 years' postintervention (2008) by telephone interview and review of medical records. Measures included asthma-related QoL, health care and medication use for asthma, level of self-regulation, self-confidence in managing the condition, sex and gender role-related asthma problems, and days of missed work or school because of asthma. Data were analyzed using both generalized estimating equations logistic regression and log-linear regression.

RESULTS

The mean (SD) age of the 808 women participating in the study was 48.2 (13.1) years in the intervention group and 48.7 (14.3) years in the control group, and the percentage of minority participants was 15.8% and 16.3%, respectively. Despite randomization, women in the intervention group had more persistent asthma at baseline. At 2 years' postrandomization, the only significant difference in health care use was associated with scheduled office visits; no other significant health care use differences were evident. However, the women in the intervention group had a significantly greater decrease of asthma symptoms with sexual activity (P = 0.01) and greater reduction in days of work/school missed for asthma in winter months (P = 0.03), were better able to self-regulate (P = 0.01), were more confident in managing their asthma (P = 0.01), and had higher levels of asthma-related QoL (P = 0.02). They also had a greater reduction in the use of short-acting bronchodilators (ie, rescue medications) than did women in the control group (P < or = 0.05).

CONCLUSION

An intervention that focuses on female-specific aspects of asthma management may result in improved QoL and health status for women with asthma, as was evident 2 years' postintervention in this study.

Yeast cell-wall products containing beta-glucan plus ascorbic acid affect neonatal Bos taurus calf leukocytes and growth after a transport stressor

The objectives were to ascertain whether a yeast cell-wall derivative that was 1.8% beta-glucan in combination with ascorbyl-2-polyphosphate could improve innate immunity and mediate transportation stress in neonatal calves, and to compare the 1.8% beta-glucan yeast cell-wall derivative with a more purified yeast cell-wall derivative (70% beta-glucan). Treatments were 1) an unsupplemented control (CNT); 2) 113 g of a 1.8% (approximately 2%) beta-glucan derivative of yeast cell walls plus 250 mg of l-ascorbic acid phosphate (BG2); or 3) 150 mg of a purified beta-glucan fraction from yeast cell walls (approximately 70% beta-glucan) plus 250 mg/feeding of l-ascorbic acid phosphate (BG70). Calves (n = 39) were transported for 4 h, placed in outdoor hutches, and randomly assigned to treatments. Treatments (mixed with a milk replacer) were individually fed twice daily for 28 d. Calves were offered calf starter, free choice, throughout the study. Weekly starter intake and BW were measured, and fecal samples were collected for Salmonella Typhimurium and Escherichia coli O157:H7 PCR analysis. Blood was collected immediately before transport (d 0) and on d 3, 7, 10, 14, 21, and 28 after transport. Starter intake and DMI were less (P < 0.05) at d 28 for the BG2 and BG70 treatments compared with the CNT treatment. Hematocrit percentages increased (P = 0.002) throughout the experiment. White blood cell counts (treatment x time interaction, P = 0.066) were less for the calves supplemented with BG70 than for those supplemented with BG2 (P = 0.01) or for CNT calves (P = 0.04) on d 28. Granulocyte counts changed (P = 0.04) throughout the experiment. A trend (P = 0.077) for a treatment x time interaction was detected for peripheral blood mononuclear cell counts (PBMC). Counts of PBMC were greater (P = 0.006) for the BG2 treatment compared with the CNT treatment on d 3. Calves given the BG70 supplement had fewer PBMC than those given the BG2 supplement on d 21 (P = 0.03) and 28 (P = 0.05). Fibrinogen concentrations were affected only by time (P = 0.002). Time effects were detected for phagocytosis (P = 0.005), oxidative burst (P < 0.001), expression of cluster of differentiation 18 (P = 0.001), and increased cluster of differentiation 18 (P = 0.006). Phagocytosis was less (P = 0.05) for calves in the BG70 group than for those in the CNT group. Percentage of calves positive for E. coli O157:H7 was greatest (P <or= 0.05) for those in the BG2 group on d 7 compared with those in the other treatments. The BG2 and BG70 supplements both increased feed intake, but only the BG2 supplement increased E. coli shedding on d 7, and the BG2 and BG70 supplements varied in modulating immune functions, indicating differences in yeast extract function.

Overweight women and management of asthma

PURPOSE

We sought to describe clinical and psychosocial characteristics of overweight women with asthma.

METHODS

Telephone interview and medical record review involving 808 women with asthma participating in a randomized study to identify those who were overweight. We assessed the relationship of their weight to asthma symptoms, health care use, quality of life, self-esteem, need for social support, and demographic characteristics. Regression analyses were used to investigate relationships between overweight and asthma.

FINDINGS

Sixty-eight percent of the women in the study were overweight or obese. Demographic characteristics associated with overweight in women with asthma included being minority (p=.000), having a lower education level (p=.000), and a lower household income (p=.024). Overweight was associated with greater health care use, comorbidities (acid reflux, urinary incontinence), and persistent disease (p=.001). Overweight women exhibited lower self-esteem (p=.002) and lower perceived quality of life (p=.000).

CONCLUSION

Overweight females with asthma experience significant challenges because of their weight, more persistent and severe disease, specific comorbidities, and lower rates of obtaining psychosocial resources. Clinical consultations and interventions should account for the influence of overweight on asthma control and health status in female patients.

Loss of the SMRT/NCoR2 corepressor correlates with JAG2 overexpression in multiple myeloma

Multiple myeloma (MM) is a clonal B-cell neoplasm that accounts for 10% of all malignant hematologic neoplasms and that affects terminally differentiated B cells (i.e., plasma cells). It is now well recognized that the cytokine interleukin-6 (IL-6) is a major cytokine that promotes the proliferation of malignant plasma cells in MM. The IL-6 gene can be regulated by the NOTCH genes products. We have previously shown that the NOTCH ligand, JAG2, is overexpressed in MM. To investigate the mechanism(s) leading to JAG2 overexpression in MM, we assessed potential epigenetic modifications of the JAG2 promoter. We showed that the JAG2 promoter region is aberrantly acetylated in MM cell lines and patient samples. The acetylation state of histones is regulated by the recruitment of histone deacetylases (HDAC). HDACs are typically recruited to promoter regions through interaction with nuclear corepressors such as SMRT. SMRT levels were therefore investigated. Interestingly, MM cell lines and patient samples presented significantly reduced SMRT levels. The experiments suggest a correlation between constitutive acetylation of the JAG2 core promoter in the MM cell lines and reduced levels of the SMRT corepressor that recruits HDAC to promoter regions. Finally, SMRT function restoration induced JAG2 down-regulation as well as MM cell apoptosis.