Species-Specific Responses to Human Trampling Indicate Alpine Plant Size Is More Sensitive than Reproduction to Disturbance.

Human disturbance, such as trampling, is an integral component of global change, yet we lack a comprehensive understanding of its effects on alpine ecosystems. Many alpine systems are seeing a rapid increase in recreation and in understudied regions, such as the Coast Mountains of British Columbia, yet disturbance impacts on alpine plants remain unclear. We surveyed disturbed (trail-side) and undisturbed (off-trail) transects along elevational gradients of popular hiking trails in the T'ak't'ak'múy'in tl'a In'inyáxa7n region (Garibaldi Provincial Park), Canada, focusing on dominant shrubs (Phyllodoce empetriformis, Cassiope mertensiana, Vaccinium ovalifolium) and graminoids (Carex spp). We used a hierarchical Bayesian framework to test for disturbance by elevation effects on total plant percent cover, maximum plant height and diameter (growth proxies), and buds, flowers, and fruits (reproduction proxies). We found that trampling reduces plant cover and impacts all species, but that effects vary by species and trait, and disturbance effects only vary with elevation for one species' trait. Growth traits are more sensitive to trampling than reproductive traits, which may lead to differential impacts on population persistence and species-level fitness outcomes. Our study highlights that disturbance responses are species-specific, and this knowledge can help land managers minimize disturbance impacts on sensitive vegetation types.

Integrating demographic niches and black spruce range expansion at subarctic treelines.

When investigating relationships between species' niches and distributions, niches can be divided demographically, resulting in unique niches for different life stages. This approach can identify changing substrate requirements throughout a species' life cycle. Using non-metric multidimensional scaling, we quantified microsite conditions associated with successful recruitment in the tundra landscape and successful seed production amongst adult trees of black spruce (Picea mariana) at subarctic treeline in Yukon, Canada to assess how life stage-specific requirements may impact the distribution of this widespread boreal tree species. Treeline ecotones in this region showed high heterogeneity in tundra microsites available for establishment. Black spruce exhibited changing microsite associations from germination to reproductive maturity, which were mainly driven by changes in plant community and soil moisture. These associations limit the microsites where individuals can establish and reproduce to a subset available within the heterogeneous landscape. Overall, we suggest that (1) substrates suitable for early recruitment are limited at the range edge; and (2) reproductive adults have a narrow niche, limiting successful seed production in adults and forming sink populations where suitable conditions are limited. Our multivariate assessment of microsite suitability can provide valuable insights into the spatial distribution of a species throughout its life cycle and identify life stage-specific constraints to range expansion.

Email Reminders Increase the Frequency That Pet Owners Update Their Microchip Information.

Stray animals with incorrect microchip details are less likely to be reclaimed, and unclaimed strays are at increased risk of euthanasia. A retrospective cohort study was performed using 394,747 cats and 904,909 dogs registered with Australia's largest microchip database to describe animal characteristics, determine whether annual email reminders increased the frequency that owners updated their information, and to compare frequencies of microchip information updates according to pet and owner characteristics. More than twice as many dogs (70%) than cats (30%) were registered on the database; the most numerous pure-breeds were Ragdoll cats and Staffordshire Bull Terrier dogs, and the number of registered animals per capita varied by Australian state or territory. Owners were more likely (p < 0.001) to update their details soon after they were sent a reminder email, compared to immediately before that email, and there were significant (p < 0.001) differences in the frequency of owner updates by state or territory of residence, animal species, animal age, and socioeconomic index of the owner's postcode. This research demonstrates that email reminders increase the probability of owners updating their details on the microchip database, and this could reduce the percentages of stray animals that are unclaimed and subsequently euthanized.

Dietary Vitamin A and Visceral Adiposity: A Modulating Role of the Retinol-Binding Protein 4 Gene.

BACKGROUND/AIMS: Visceral fat (VF) compared with subcutaneous fat (SF) is more closely associated with cardiometabolic disease. Dietary vitamin A (retinol) may reduce adiposity through its effects on adipogenesis differentially in VF and SF, and this effect may be modulated by retinol-binding protein-4 (RBP4). We investigated whether intake of vitamin A is associated with either VF or SF, and whether this association is moderated by the RBP4 genotype (rs10882272, C/T) previously associated with circulating retinol levels. METHODS: This was a cross-sectional association study in a sample of 947 adolescents from a French-Canadian founder population. VF and SF were quantified with magnetic resonance imaging, and vitamin A intake was assessed with a 24-hour food recall. All participants were genotyped to determine their RBP4 variant. RESULTS: Dietary intake of vitamin A was negatively associated with VF; however, it was not associated with SF. These relationships were independent of age, sex, height and energy intake, and were modulated by the RBP4 variant. The T allele promoted adiposity-reducing effects of vitamin A in VF and adiposity-enhancing effects in SF, while the C allele had adiposity-reducing effects in both VF and SF. CONCLUSIONS: Dietary vitamin A may reduce abdominal adiposity and promote visceral to subcutaneous body fat redistribution during adolescence in an RBP4-dependent manner. These observational findings provide the basis for future interventional studies, which together with genetic information may inject further causality in the association between dietary vitamin A intake and abdominal adiposity.

Routine clinical measures of adiposity as predictors of visceral fat in adolescence: a population-based magnetic resonance imaging study.

OBJECTIVE: Visceral fat (VF) increases cardiometabolic risk more than fat stored subcutaneously. Here, we investigated how well routine clinical measures of adiposity, namely body mass index (BMI) and waist circumference (waist), predict VF and subcutaneous fat (SF) in a large population-based sample of adolescents. As body-fat distribution differs between males and females, we performed these analyses separately in each sex. DESIGN AND METHODS: VF and SF were measured by magnetic resonance imaging in 1,002 adolescents (482 males, age 12-18 years). Relationships of BMI and waist with VF and SF were tested in multivariable analyses, which adjusted for potentially confounding effects of age and height. RESULTS: In both males and females, BMI and waist were highly correlated with VF and SF, and explained 55-76% of their total variance. When VF was adjusted for SF, however, BMI and waist explained, respectively, only 0% and 4% of VF variance in males, and 4% and 11% of VF variance in females. In contrast, when SF was adjusted for VF, BMI and waist explained, respectively, 36% and 21% of SF variance in males, and 48% and 23% of SF variance in females. These relationships were similar during early and late puberty. CONCLUSIONS AND RELEVANCE: During adolescence, routine clinical measures of adiposity predict well SF but not VF. This holds for both sexes and throughout puberty. Further longitudinal studies are required to assess how well these measures predict changes of VF and SF over time. Given the clinical importance of VF, development of cost-effective imaging techniques and/or robust biomarkers of VF accumulation that would be suitable in everyday clinical practice is warranted.

Risk of third-trimester amniocentesis: a case-control study.

Risks of third-trimester amniocentesis are considered minimal; however, only case series have been reported. We performed a case-control study in which women undergoing third-trimester amniocentesis were matched with controls undergoing antenatal testing for similar indications to determine adverse outcomes associated with the procedure. Cases undergoing amniocentesis at > 32 weeks for fetal lung maturity assessment followed by antepartum testing with nonstress test and amniotic fluid index determination were matched with controls undergoing only antepartum testing based on gestational age at testing and maternal age. The main outcome variable was a composite occurrence of obstetric complications within 48 hours of testing, including urgent delivery, placental abruption, premature rupture of membranes (PROM), perinatal death, or Apgar score at 5 minutes < 7. Statistical analysis included Fisher's exact test and Student T-test, with P < 0.05 considered significant. A total of 167 matched pairs of patients fulfilled the study criteria. Indications for both amniocentesis and antepartum testing, which included diabetes, preterm labor, and cholestasis, were similar in the two groups. As expected, gestational age at sampling/testing (36.4 +/- 1.4 [mean +/- standard deviation] versus 36.6 +/- 1.7 weeks; P = 0.2) and maternal age (31.4 +/- 5.8 versus 31.5 +/- 6.3 years; P = 0.9) were not different between cases and controls. The rate of the main outcome variable within 48 hours of testing was 0 of 167 among cases and 1 of 167 among controls. Amniocentesis in the third trimester is not associated with increased risk of urgent delivery, placental abruption, PROM, Apgar score at 5 minutes < 7, or perinatal death within 48 hours of the procedure.

Role of lamellar body count for the prediction of neonatal respiratory distress syndrome in non-diabetic pregnant women.

OBJECTIVE: Lamellar body count is a new and fast technique to establish the presence of fetal lung maturity. We have assessed the predictive ability of lamellar body count for neonatal respiratory distress syndrome (RDS) in a non-diabetic population. STUDY DESIGN: We accessed a cohort of amniocenteses in non-diabetic women from 1998 to 2002 (n=102). Neonatal RDS was defined as need for surfactant, intubation, or continuous positive airway pressure (CPAP) in the setting of chest X-ray findings consistent with RDS. The predictive ability of lamellar body count was compared with those of lecithin/sphingomyelin (L/S) ratio and presence of phosphatidylglycerol (PG) using logistic regression analysis. The optimal threshold value of lamellar body count for prediction of neonatal RDS was established with receiver operating characteristic (ROC) curve analysis. RESULTS: Lamellar body count ROC curve analysis identified a lamellar body count >37,000 microl(-1) as optimal diagnostic threshold for diagnosis of lung maturity, having a negative predictive value of 98%. Lamellar body count and PG, but not L/S ratio, added significantly to the prediction of RDS. CONCLUSIONS: Lamellar body count is a reliable predictor of fetal lung maturity in non-diabetic women and it can replace the L/S ratio.

Differential expression of c-fos in a mouse model of fetal alcohol syndrome.

OBJECTIVE: Fetal alcohol syndrome (FAS) results in stillbirth, fetal growth restriction, and mental retardation with injury attributed to oxidative stress. Our objective was to identify signal transduction pathways expressed in a model of FAS and to quantify expression of c-fos, a gene in the stress signal pathway. STUDY DESIGN: Timed, pregnant C57Bl6/J mice were injected on E8 with saline solution or alcohol. RNA was extracted from decidua and embryo 6 and 24 hours later. Microarray analysis was used to screen gene pathways. Differential gene expression was confirmed using real-time polymerase chain reaction with results presented as the ratio of c-fos concentration to that of glyceraldehyde-3-phosphate dehydrogenase (GAPDH). RESULTS: Differential gene expression between alcohol and control was noted for stress signal pathway genes including c-fos. Real-time polymerase chain reaction demonstrated that c-fos messenger RNA expression was greater in the alcohol than control decidua at 6 hours after injection (P<.01). This effect persisted at 24 hours (P<.01). There was no difference in c-fos expression in embryos whose mothers received alcohol versus control after 6 hours (P=.12) or 24 hours (P=.89). CONCLUSION: Alcohol administration during pregnancy results in differential gene expression in the stress signal pathway, particularly in c-fos. C-fos expression in the decidua increases from 6 to 24 hours after alcohol injection, but does not change in the embryo, which may contribute to alcohol-induced damage in FAS.

The role of activity-dependent neuroprotective protein in a mouse model of fetal alcohol syndrome.

OBJECTIVE: Fetal alcohol syndrome (FAS) is the most common nongenetic cause of mental retardation. Peptides NAPVSIPQ (NAP) and SALLRSIPA (SAL), related to activity-dependent neuroprotective protein (ADNP), prevent alcohol-induced damage in a mouse model of FAS. Our objective was to characterize ADNP in this model to relate this protein to the mechanisms of damage and peptide neuroprotection. STUDY DESIGN: Timed, pregnant C57Bl6/J mice were treated on day 8. Groups were control, alcohol, peptide pretreatment, or peptide alone. Embryo and decidua were harvested at 6 and 24 hours and 10 days. To evaluate ADNP expression, real-time polymerase chain reaction was performed with results presented as the ratio of ADNP-to-glyceraldehyde-3-phosphate dehydrogenase (GAPDH) concentration. Analysis of variance was performed for overall comparisons with P<.05 considered significant. RESULTS: At 6 hours, there was no difference in ADNP between alcohol-exposed embryos compared with control embryos. At 24 hours, there was an increase in ADNP in alcohol-exposed embryos compared with controls (P<.001); these findings persisted at 10 days (P<.001). In the decidua at 6 hours, there was no difference between alcohol and control. At 24 hours, there was greater ADNP in alcohol-exposed decidua compared with controls (P<.001), which did not persist at 10 days (P=.97). Peptide pretreatment did not prevent the alcohol-induced increase in ADNP in embryo or decidua. CONCLUSION: Alcohol increased embryonic and decidual ADNP expression at 24 hours and it persisted in the embryo for 10 days. Because ADNP is a known neuroprotectant, these findings suggest that it may be released as a protective mechanism in FAS. Changes in the embryo were persistent suggesting that the embryo is more vulnerable to alcohol-induced damage than the mother.

Total versus subtotal hysterectomy: a survey of gynecologists.

OBJECTIVE: To estimate the attitudes and practice of gynecologists in the Washington, DC, Maryland, and Virginia area regarding total versus subtotal abdominal hysterectomy. METHODS: A questionnaire with 18 questions on physicians' attitudes and practice regarding total versus subtotal hysterectomy was mailed to 1647 gynecologists in Washington, Maryland, and Virginia. RESULTS: The corrected response rate was 51.2%. Forty-five percent of respondents stated that they always removed the cervix. The most common reason cited was to eliminate the risk of cervical cancer. The most common reason for subtotal hysterectomy was surgical difficulty leading to an intraoperative change of procedure. Only 17.8% of respondents always counseled women regarding the advantages and disadvantages of both total and subtotal hysterectomy; 63% rarely or never did. Nineteen percent always offered women a choice between the procedures; 61% rarely or never did. Eighty-eight percent of respondents felt that the risk of cancer in the cervical stump was small or negligible. Gender of the physicians or year of completion of residency made no significant impact on patients being counseled about both procedures or being offered a choice between the two. CONCLUSION: Most gynecologists surveyed favor total abdominal hysterectomy over subtotal hysterectomy. Few counsel women regarding the options of total and subtotal hysterectomy or offer a choice between the procedures. Given that there are no convincing data proving the superiority of either procedure over the other, it may be reasonable to discuss the potential advantages and disadvantages of both procedures with women undergoing hysterectomy for benign disease and to offer them a choice.

Lecithin/sphingomyelin ratio and lamellar body count. What values predict the presence of phosphatidylglycerol?

OBJECTIVE: To assess which values of the lecithin/sphingomyelin (L/S) ratio and lamellar body count (LBC) optimally correspond to the presence of phosphatidylglycerol (PG). STUDY DESIGN: A database of clear amniotic fluid specimens obtained by amniocentesis was accessed. Receiver operating characteristic curve analysis was performed for both L/S ratio and LBC to identify the optimal thresholds for predicting the presence of PG. RESULTS: One hundred eighty-eight patients were included in the analysis. "Trace" PG was more like "absent" PG in relation to both L/S ratio and LBC. There were significant relationships between L/S ratios and presence of PG (area under the curve = .909, P < .0001) and between LBC and presence of PG (area under the curve = .94, P < .0001). The positive predictive value of L/S ratio > 2 was 76%, and that of LBC > 30,000 was 82% in predicting the presence of PG. Optimal threshold values for the prediction of PG presence were > 3.0 for L/S ratio, which had a positive predictive value of 95% and false positive rate of 5%, and > 50,000 for LBC, with a 96% positive predictive value and 5% false positive rate. CONCLUSION: "Mature" results for PG in amniotic fluid are equivalent to an L/S ratio of > 3.0 and LBC > 50,000 and help explain the later gestational age at the appearance of lung maturity by PG than by L/S > 2 or LBC > 30,000.

Differential expression of embryonic and maternal activity-dependent neuroprotective protein during mouse development.

OBJECTIVE: Activity-dependent neuroprotective protein (ADNP) potently enhances the survival of neurons and is regulated by vasoactive intestinal peptide, which also mediates postimplantation mouse embryonic growth. The objective of this study was to characterize ADNP in mouse embryonic tissues throughout development. STUDY DESIGN: Developmental tissues (embryo, decidua, placenta) from timed pregnant C57B16/J mice were harvested on days 6 though 18. To evaluate ADNP expression, RNA was extracted from at least three samples from three different mice per day. Five micrograms of total RNA from each sample was used per reverse transcriptase-polymerase chain reaction. Immunocytochemistry with anti-ADNP-derived peptide immunoglobulin and anti-gammadelta T-cell receptor was performed on 20 microm thick fixed sections of day 9.5 uteri. RESULTS: Embryonic ADNP messenger RNA (mRNA) has a temporal pattern with greater amounts present from gestational days 9 to 16. Placental ADNP mRNA was uniformly expressed on gestational days 11 to 18. Levels of decidual ADNP mRNA were greatest early in gestation and declined until delivery. Within the decidua, ADNP and gammadelta T-cell receptor immunoreactivity was present in the same cells. CONCLUSION: The expression of ADNP during pregnancy supports a developmental role for this protein. These data indicate both embryonic and maternal sources of ADNP during the critical period of organogenesis.

Vasoactive intestinal peptide mRNA and immunoreactivity are decreased in fetal alcohol syndrome model.

Vasoactive intestinal peptide (VIP) regulates growth in the early post-implantation embryo. Previous work has demonstrated that peptide agonists (SALLRSIPA and NAPVSIPQ) from downstream mediators that are regulated by VIP were able to prevent the alcohol-induced fetal death, growth restriction and microcephaly associated with fetal alcohol syndrome. Here we evaluated the role of VIP in this mouse model of fetal alcohol syndrome, to determine if fetal or maternal levels of VIP are altered. In addition, we evaluated whether peptide treatment would alter the effects of alcohol on VIP levels. Treatment groups included control, alcohol, and alcohol+peptides. VIP levels were measured with enzyme immunoassay [EIA] (Peninsula Laboratories, Belmont, CA). Quantitation of VIP expression was measured with rt-PCR using mimic cDNA primers. Embryo/decidual VIP levels were similar in control and alcohol-treated groups 6 h after treatment. However, in the embryo/deciduas at 12 and 24 h, VIP levels were below the EIA's detection limit in the alcohol-treated groups, and significantly lower than the control or peptide-pretreated groups (p<0.05). Maternal cortex VIP levels were undetectable and significantly lower in the alcohol-treated group than control or peptide+alcohol group at 6 and 12 h (p<0.001). VIP mRNA expression was quantitated in the embryo and deciduas, with a significant decline noted at 6 h to 58% of control levels (p=0.02). Pretreatment with the peptides attenuated the alcohol-induced decrease in VIP mRNA. These studies demonstrate that treatment with alcohol can decrease the expression and immunoreactivity of VIP in both maternal and fetal tissues. This alcohol-induced loss of a recognized regulator of embryonic growth and differentiation may contribute to the sequelae of toxicity observed in fetal alcohol syndrome.