Good Predictor Of Occurrence Research Articles

Role of Polyomavirus BK and Adenovirus in the Development of Urinary Tract Complications in Pediatric Hematopoietic Stem Cell Transplantation

One of the major challenges in pediatric hematopoietic stem cell transplantation (HSCT) is the susceptibility to viral infections and reactivations that can lead to potentially life-threatening complications and increase the transplant-related mortality (TRM). Polyomavirus BK (BKPyV) and Adenovirus (AdV) represent the predominant causes of urinary tract complications, in particular hemorrhagic cystitis (HC), in HSCT recipients. Treatment options for BKPyV and AdV infections are limited and there is no accepted standard of care for the prevention and treatment of these HSCT complications. The aim of our retrospective study was to analyze the incidence of BKPyV and AdV infection in urinary and plasma samples of pediatric patients undergoing HSCT for both malignant and non-malignant disease at a single pediatric Hematology-Oncology unit. Endpoints were the cumulative incidence of infection, measured on blood and urine samples, in the first 100 days after HSCT, prevalence of asymptomatic and symptomatic infection, and correlation between BKPyV and AdV DNAemia and DNAuria and the development of HC. A total of 79 patients were analyzed. Thirty-seven (47%) patients were positive for BKPyV on urine samples and 20 (30%) on blood samples within the first 30 days after transplantation. As for AdV, 11 (9%) patients were positive on urine samples and 18 (15%) on blood samples. In our pediatric cohort, BKPyV DNAuria was a frequent event after HSCT, while BKPyV DNAemia was observed less frequently, and was accompanied by higher viruria values (p-value <0,001, with a median viral load in the urine of 3.8 x 10 9 copies/mL). Conversely, AdV positivity in urine is rare, while AdV DNAemia was more frequent, due to the modality of BKPyV and AdV distribution (urothelium is the main reservoir for BKPyV, while intestinal lymphocytes represents the main reservoir for AdV). Of the 37 patients with BKPyV DNA on urine samples, 11 (30%) developed a symptomatic infection with grade II (5 patients, 40%) and grade III (6 patients, 60%) HC. We did not observe any correlation between BKPyV DNA urinary levels and the development of HC, as higher viral loads have not been shown to be good predictors of occurrence or severity of HC. Cumulative incidence (CI) of BKPyV infection was higher in haploidentical HSCT (51%) and matched unrelated donors (MUD) (48%) than in HSCT from matched familiar donors (31%). Similarly, CI of AdV reactivation was higher in haploidentical HSCT (16%) than MUD (6%) and matched familiar donors (9%). Choice of donor, the type of immunosuppression used and the intensity of conditioning regimen represented predictors of both blood and urine DNA positivity for both viruses. In our cohort, positivity for BKPyV on blood and/or urine did not increase the risk of transplant-related mortality and did not affect the overall survival after HSCT. On the basis of our data, we now perform screening of BKPyV viruria only in symptomatic patients or in transplant recipients with specific risk factors (type of donor, severity of immunosuppression). Similarly, search for BKPyV DNAemia is reserved to subjects with a high viral load on urine. Likewise, search for AdV on urine samples is performed on symptomatic patients with high-load AdV DNAemia.

Stream Amphibian Detectability and Habitat Associations in a Reduced Impact Logging Concession in Malaysian Borneo

Borneo's amphibians face an uncertain future due to high levels of forest degradation and a paucity of data for effective conservation management. Several studies identified strong species–habitat relationships in pristine and conventionally logged forests. However, these studies did not account for detectability or habitat associations in sustainably managed forest reserves. Here, we determined detectability and species habitat relationships in stream amphibians within the Deramakot forest reserve, a reduced impact logging concession in the Malaysian state of Sabah, northern Borneo. We analyzed data for 10 stream species collected along 32 stream transects. An occupancy modeling framework was used to determine the climatological, temporal, and environmental covariates associated with detection and occupancy probabilities. We identified high variability in detection probability between species, including significant associations with moon phase (six species), time since sunset (five species), humidity (five species), rainfall (four species), and temperature (three species). Stream slope and volume provided by far the best predictors of occurrence, with significant positive or negative associations with the occupancy of six species each. These associations were more similar to those found in pristine compared with conventionally logged habitats. The highly variable detectability associations within our amphibian community suggest a level of temporal separation in regard to activity and breeding phenology in these species. This stresses the importance of accounting for detection probability via surveying sites across varying climatic/temporal conditions to obtain a representative sample of amphibian communities in pristine and disturbed tropical forests.

Identification of reliable predictors of golden sun moth Synemon plana habitat over multiple survey years can benefit conservation, restoration and surveys for new populations

Native grasslands, and the fauna that inhabit them, are globally some of the most threatened ecosystems and organisms. Knowledge of the relative importance of climate, landscape context and site-based resources for local insect populations is critical for the restoration and conservation of these communities. We investigated the site and landscape-scale best predictors of occurrence and abundance over three consecutive years of sampling, for the critically endangered golden sun moth Synemon plana in south-eastern Australia. We found eight vegetation factors to be significantly associated with golden sun moth occurrence using data from combined survey data and data for each year alone; we identified just three common factors from year to year. Modelling indicated that Austrostipa and Rytidosperma species richness was the most consistent parameter, but for each year alone, there was a combination of aspect, landscape position and Austrostipa and Rytidosperma species richness. Our study shows that environmental characteristics where golden sun moth occur are relatively predictable over multiple years. This information can be used to protect sites where monitoring of extant populations is yet to occur, predict the location of new populations in the region, and restore adjacent habitat that is suitable but degraded.

Environmental Factors Governing Soil Water Repellency Dynamics in a Pinus Pinaster Plantation in NW Spain

AbstractSoil water repellency (SWR) is a dynamic property that changes throughout the year. The objective of this work was to identify the environmental factors governing the temporal patterns in SWR in a pine plantation in northwest Spain with a view of predicting its occurrence and persistence. For this purpose, 24 samples were collected from the soil surface (0–5 cm) at 25 different times over a 1‐year period and analysed for SWR by using water drop penetration time test and soil moisture measurements. Temporal variations in SWR exhibited a well‐defined seasonal pattern. The soil surface was largely wettable from late autumn to early spring and extremely water repellent during summer and early autumn. Repellency persistence was rather variable during spring. There was highly significant correlation between SWR and soil moisture content. The moisture range defining the presence or absence of repellency under field conditions was 22–57%. There were also significant correlations with the target variables (maximum temperature, minimum temperature, precipitation and water balance during variably long antecedent periods), with coefficients that increased with increasing length of the antecedent period considered. The moisture content of soil at the time of sampling and the average maximum temperature for the 28 days before sampling are the best predictors of occurrence of SWR and its persistence in different seasons. Copyright © 2015 John Wiley & Sons, Ltd.

Quantitative analysis of serum levels of trace elements in patients with oral submucous fibrosis and oral squamous cell carcinoma: A randomized cross-sectional study.

Background and Objectives:Metabolic disorders, oral precancerous conditions and oral cancer are accompanied by alterations in the concentration of one or more trace elements like copper, iron, zinc, magnesium etc., in some body fluids, especially blood serum or plasma, which can help not only in the early diagnosis and treatment but also in prognosis. The objective of the study is to evaluate the levels of circulating trace elements (copper, iron, magnesium, zinc and calcium) in serum of patients with Oral Submucous Fibrosis (OSF) and Oral Squamous Cell Carcinoma (OSCC), to analyze the alteration and identify the best predictors amongst these parameters for disease occurrence and progression and their association with areca nut and betel quid chewing habits.Materials and Method:Serum levels of trace elements (copper, iron, magnesium, zinc and calcium) were estimated using electronic absorption colorimetric method. These levels were compared with controls and statistically evaluated using ANOVA and POST-HOC TUKEY tests.Results:The data analysis revealed that serum copper levels increased gradually from precancer to cancer, as the duration of betel quid chewing habit increased. However, serum iron, magnesium, zinc levels were decreased significantly in both the groups. Serum calcium levels were increased in the cancer group owing to bone resorption in the later stages of the disease, whereas it was close to normal in OSF patients. Among all the trace elements, the best predictor for occurrence of both the lesions was copper.Conclusion:The present study shows that the above trace elements may be associated with the pathogenesis and progression of OSF and OSCC. Betel quid and areca nut chewing habits are frequently associated with both disease states and may play a role in altering the serum levels of these trace elements. Concerted efforts would, therefore, help in early detection, management and monitoring the efficacy of treatment.

Landscape and habitat characteristics associated with fish occurrence and richness in southern Brazil palustrine wetland systems

We investigated the influence of environmental factors in fish communities of 146 palustrine wetlands, covering a wide range of altitude and wetland surface area in Neotropical region. Two questions were analyzed: (1) Are wetland altitude, area, habitat diversity, hydroperiod (permanent and intermittent), ecoregion, and macroinvertebrate richness good predictors of occurrence, richness, abundance and composition of fish species? and (2) Are the predictors of fish richness similarly applicable to different ecoregions in Southern Brazil? Our data showed that fish richness was related to habitat diversity and macroinvertebrate richness, and fish occurrence was influenced by wetland area and macroinvertebrate richness. Fish abundance was influenced by altitude, hydroperiod and macroinvertebrate richness, and the fish composition was jointly associated with ecoregion, and hydroperiod. The predictors of fish richness were not similarly applicable to different ecoregions. Our results showed that the habitat diversity, macroinvertebrate richness, altitude and hydroperiod were the environmental predictors that potentially structure and maintain the fish occurrence and richness in southern Brazil palustrine wetlands. Such information is essential to develop wetland conservation and management programs in this region, where more than 90 % of wetland systems have already been lost and the remaining ones are still at high risk due to the anthropogenic activities.

Vegetation structural and compositional heterogeneity as a key feature in Alpine black grouse microhabitat selection: conservation management implications

European Alpine landscapes are facing marked land-use changes. On the one hand, outdoor winter recreation is spreading, with ski infrastructure degrading fragile mountain habitats, and snowsports causing disturbance and stress to wildlife. On the other hand, the abandonment of traditional grazing practices on timberline grasslands is leading to their encroachment by shrubs and forest, which decreases habitat heterogeneity and negatively affects biodiversity. We used the black grouse, a declining key indicator species of the Alpine timberline ecosystem, to assess optimal breeding habitat characteristics, with the goal of providing guidelines for appropriate restoration. Using Mixed Effects Logistic Regression analyses, we compared habitat features both at visited and at pseudo-absence locations within individual home ranges in order to determine the optimal habitat for males and females. Horizontal and vertical structural heterogeneity within all vegetation layers was the best predictor of occurrence for both sexes. In contrast, vegetation composition affected the presence of females, but not that of males. Females preferred a diverse, complex mosaic consisting of isolated mature coniferous trees and scattered small regenerating trees, associated with shrub cover (Ericacea) and Alpine meadows (Nardion). Chick-rearing females furthermore avoided roads, forest tracks and walking paths. The optimal predicted proportions of habitat types obtained from the model provide guidelines for the restoration of timberline ecosystems through corrective forestry measures and/or adapted grazing practices. These measures are likely to also benefit other Alpine timberline biodiversity.

The Shared Preference Niche of Sympatric Asiatic Black Bears and Sun Bears in a Tropical Forest Mosaic

BackgroundEcologically similar species often coexist by partitioning use of habitats or resources. Such partitioning can occur through divergent or shared niches. We investigated overlap in habitat use and spatial co-occurrence by sympatric Asiatic black bears and sun bears in three habitats in Thailand, and thereby assessed which niche model best accounts for their coexistence.Methods/Principal FindingsWe used density of species-specific signs to assess habitat use. Signs of both bear species occurred in all three habitats, and on >60% of sampling transects. Both species fed mostly on fruit; insect feeding signs were uncommon, and were mostly from sun bears. Significant differences in habitat use occurred only in montane forest, the habitat in which fruit was most abundant; incidence of black bear sign there was six times higher than that of sun bears. Habitat use was similar between the two species in the other habitats, which comprised 85% of the area. Of 10 habitat attributes examined, fruiting tree density was the best predictor of occurrence for both species. Models that included interspecific competition (fresh foraging activity of the other species) were less supported than the top models without competition.Conclusions/SignificanceBear species co-occurrence at both coarse and fine spatial scales and use of the same resources (fruit trees) indicated common niche preferences. However, their habitat use differed in ways expected from their physical differences: larger black bears dominated in the most fruit-rich habitat, and smaller sun bears used less-preferred insects. These results indicate broadly overlapping fundamental niches combined with asymmetric competition—features consistent with the concept of shared preference niches. This model of the niche has received little attention in ecology, but appears to be relatively common in nature.

Predicting patterns of richness, occurrence and abundance of small fish in New Zealand estuaries

Estuarine fish habitats are vulnerable to human impacts and are poorly studied. We surveyed 69 of New Zealand’s 443 estuaries across 1500 km to: determine species composition of small fishes; model and predict their richness, occurrence and abundance; test marine classification schemes as a basis for Marine Protected Areas; and inform impact mitigation measures. Boosted regression tree models produced acceptable fits for richness and occurrence at estuary and site scales and abundance at the site scale. Richness was greatest in northern North Island; the best predictors were estuary area and area of intertidal habitat. Within estuaries, richness increased towards the head, as water clarity declined and the substratum became muddier. Air temperature, estuary and intertidal area, tidal range and freshwater and seawater influx were the best predictors of occurrence at the estuary scale; water temperature and salinity were important at the site scale. Biological classification schemes seldom improved model fits and have little predictive utility. Richness predictions were made for 380 estuaries and occurrence predictions for 16 species. These predictions inform resource managers about estuarine fishes within their jurisdiction, bypassing the need to undertake expensive field surveys. However, sampling of environmental predictors is still required to drive some models.

Nest site selection and the effects of land use in a multi-scale approach on the distribution of a passerine in an island arid environment

We examine the predictive ability of habitat-species relationship models in island semi-desert environments using as model species the Canary Islands stonechat ( Saxicola dacotiae), an endemic bird inhabiting the arid island of Fuerteventura. We investigated nest site selection and the effects of land use on its distribution in a multi-scale approach using nest positions obtained during three consecutive breeding seasons. We identified two environmental predictors, namely Tasseled cap 1 (a range value of land brightness) and slope, and three variables derived from human use (house densities, unpaved roads and fences) as the best predictors of occurrence of the species. Only slope had a positive and significant effect on stonechat occurrence; the rest being negative. Results were not restricted by the scale, indicating that design of special protection areas should be developed considering the landscape scale. Our results provide a robust prediction of the species distribution throughout Fuerteventura, demonstrating that our approach can also cope for the low vegetation signal within small arid regions such as islands. Future land use planning and management for the island should avoid the presence of negative impact elements such as opening new roads and new urbanisations in nearby habitats with the highest probabilities of species occurrence.

Abstract A22: Spirometric surveillance for premalignant and malignant bronchial lesions

Abstract Background: Chronic obstructive pulmonary disease (COPD) and lung cancer (LC) are diseases that share common risk factors. It has been reported that more than half of the patients diagnosed with LC also suffer from COPD. Although COPD is a well known risk factor for LC, the relationship between impaired lung function (LF) and the incidence and progression of pre-malignant lesions (PMLs) in the central airways is still unclear. Methods: The study included 217 high-risk patients from a hospital-based lung cancer surveillance cohort who underwent bronchoscopy with endobronchial biopsy of suspicious lesions, at the Roswell Park Cancer Institute, Buffalo, New York. All patients had lung function measurement within 6 months preceding their baseline biopsy. Baseline histopathology diagnoses included 91squamous metaplasia (SM), 25 squamous dysplasia (SD), 1 in-situ carcinoma and 5 invasive bronchial carcinoma. Follow-up bronchoscopy and biopsy were performed on 69 patients. Sixteen patients had a progression of the baseline lesion to a higher grade. The relationship between the baseline LF measures and the incidence and progression of PMLs were examined using regression models. Results: Patients with forced expiratory volume in 1 second percent predicted (FEV1%) of <50% had 4.5 times greater risk of being diagnosed with PML/cancer, when compared to patients with FEV1% ≥80. Increased risk was noted for all grades of PMLs and cancers, with the risk being almost 8 times for squamous dysplasia [Odds ratio = 7.95; 95%confidence interval (CI) =1.77–35.6]. Similarly, FEV-1/FVC ratio of <50% was associated with 3 times greater risk of detecting a PML/cancer. When COPD was classified based on GOLD criteria, the patients with severe COPD had 2.7 times and 4.8 times greater risk of being detected with SM and SD, respectively. The risk persisted for SD even when an age standardized classification was used to define COPD. COPD patients also had a non-statistically significant 2.5 times greater risk of their baseline lesion progressing to a higher grade [Hazard Ratio 2.48 (95% CI 0.65 – 9.41), p-value - 0.18)]. The mean time to progression from a lower grade lesion to a higher grade was 27 months for patients with COPD and 50 months for patients without COPD. Conclusion: Impaired LF can be a good predictor of occurrence and progression of PMLs in central airways of high risk patients. Spirometric measurement of lung function can be used as an additional tool for identifying target populations in need of more aggressive LC surveillance. Citation Information: Cancer Prev Res 2010;3(1 Suppl):A22.

Habitat selection by the Canary Islands stonechat ( Saxicola dacotiae) (Meade-Waldo, 1889) in Fuerteventura Island: a two-tier habitat approach with implications for its conservation

Habitat selection by the Canary Islands stonechat ( Saxicola dacotiae), an endemic bird of Fuerteventura Island (Canary Islands, Spain), was studied in a two-tier habitat approach of microhabitat and landscape. Birds spent all their foraging time on stony fields and barrancos, avoiding lava and sandy fields. Slopes with high shrub coverage were the best predictors of occurrence of Canary Islands stonechats at a landscape scale. At a microhabitat scale, slopes with large boulders were selected, whilst those covered with small stones were clearly avoided. Birds used those places that supported the largest invertebrate densities. Two main threats to the species are: (1) grazing pressure (which could increase the process of desertification and decrease the availability of food), and (2) the destruction or alteration of optimal habitats, mainly owing to an increase in tourism development. Future management efforts should include the protection of large patches of stony field and barranco habitats, with slopes having at least 50% of shrub cover and large boulders. In addition, rigorous studies are needed to ascertain the maximum level of goat grazing for maintaining these optimal habitats for the Canary Island stonechat.

Risk Factors for Neonatal Intraventricular Haemorrhage in Spontaneous Prematurity at 32 Weeks Gestation or Less

In this study we aimed to establish which clinical and histopathological factors are associated with early-onset neonatal intraventricular haemorrhage (IVH) in non-iatrogenic preterm delivery before 32 weeks of gestation.We retrospectively reviewed all singleton pregnancies delivered before 32 weeks of gestation after spontaneous onset of preterm labour or preterm membrane rupture during the period January 1993 to June 1997. Clinical and histopathological data in cases with IVH diagnosed at neonatal cranial ultrasound within 72h of birth (n=17) were compared with those of neonates not experiencing this complication (non-IVH) (n=54). Histological lesions analysed were those of acute inflammation and those on a uteroplacental vascular basis. Statistical methods included the Wilcoxon rank sum test, Fisher's exact test, and logistic regression analysis. A P< 0.05 was considered significant.IVH and non-IVH groups were not significantly different in birthweight, gestational age at delivery, cord pH at birth, rates of 5-min Apgar score below 7, caesarean delivery, diagnosis of clinical chorioamnionitis or antenatal administration of steroids. Respiratory distress syndrome was more frequently diagnosed in the IVH than non-IVH group (64 per cent versus 33 per cent, P=0.02). Placental acute inflammatory or uteroplacental vascular lesions were present in 100 per cent of IVH neonates versus 22 per cent of non-IVH cases (P< 0.001). Logistic regression analysis demonstrated that only respiratory distress syndrome (P=0.04) and histological evidence of acute placental inflammation (P=0.02) were significantly and independently associated with IVH.Histopathological evidence of acute inflammatory placental lesions is the best predictor of occurrence of neonatal IVH.