Long‐term Effects of Prenatal Stress and Glucocorticoid Exposure

There is a growing body of evidence suggesting that events during prenatal life can have long‐lasting effects on development and adult health. Stress during pregnancy is common and has been linked to increased incidence of a range of affective and behavioral outcomes in the offspring in later life and also some somatic outcomes. Glucocorticoids, and their actions on the fetus, which are regulated by placental 11β‐hydroxysteroid dehydrogenase type 2 (11β‐HSD2), are hypothesized to mediate these effects. Animal studies have demonstrated long‐term effects of stress and glucocorticoid administration on behavioral outcomes, as well as increased blood pressure, altered hypothalamic pituitary adrenal axis (HPA) function, and decreased glucose tolerance and brain size. In humans, licorice, which inhibits placental 11β‐HSD2 when consumed during pregnancy, has been shown to increase the risk of behavioral problems linked to altered HPA activity. Synthetic glucocorticoids administered during pregnancy to improve fetal lung maturity in threatened preterm birth have been shown to reduce birth weight and head circumference, but have not been linked to grosschanges in long‐term health todate. It is important to consider thelong‐term consequences of stress, and medication that mimics stress, during pregnancy. Birth Defects Research (PartC) 96:315–324, 2012. © 2013 Wiley Periodicals, Inc.     

Long‐term ecological monitoring and institutional memories

Many important ecological management issues can only be addressed by long‐term monitoring or through studies carried out over extended periods. But such studies require institutional settings that ensure funding is sustained and that data arising from these studies are securely managed. Recent experience suggests both are difficult to achieve. This is because management agencies and research bodies are periodically restructured, especially in recent years. This has often led to long‐term work being terminated. But there is anecdotal evidence that the data collected in at least some of these studies are not always lost. Instead, it can remain stored in the back rooms of agencies or in the personal files of former staff. Such data are clearly at risk; with time fewer people remain aware of the work or of the existence of data that were collected, thereby increasing the likelihood that the information will eventually disappear. This seems a waste. Securing funds for any long‐term ecological study is always likely to be difficult, and many of these previous long‐term studies are likely to be relevant to some of our present management problems. One approach to taking advantage of these earlier studies would be to ask scientific and professional associations to survey their older members to identify relevant previous investigations. But any re‐establishment of former studies will require the creation of new institutional arrangements, more robust institutional memories and sufficient funds that are able to sustain any resurrected investigations into the future.     

Long‐term amelioration of acidity accelerates decomposition in headwater streams

The secondary production of culturally acidified streams is low, with a few species of generalist detritivores dominating invertebrate assemblages, while decomposition processes are impaired. In a series of lowland headwater streams in southern England, we measured the rate of cellulolytic decomposition and compared it with values measured three decades ago, when anthropogenic acidification was at its peak. We hypothesized that, if acidity has indeed ameliorated, the rate of decomposition will have accelerated, thus potentially supporting greater secondary production and the longer food chains that have been observed in some well‐studied recovering freshwater systems. We used cellulose Shirley test cloth as a standardized bioassay to measure the rate of cellulolytic decomposition, via loss in tensile strength, for 31 streams in the Ashdown Forest over 7 days in summer 2011 and 49 days in winter 2012. We compared this with data from an otherwise identical study conducted in 1978 and 1979. In a secondary study, we determined whether decomposition followed a linear or logarithmic decay and, as Shirley cloth is no longer available, we tested an alternative in the form of readily available calico. Overall mean pH had increased markedly over the 32 years between the studies (from 6.0 to 6.7). In both the previous and contemporary studies, the relationship between decomposition and pH was strongest in winter, when pH reaches a seasonal minimum. As in the late 1970s, there was no relationship in 2011/2012 between pH and decay rate in summer. As postulated, decomposition in winter was significantly faster in 2011/2012 than in 1978/1979, with an average increase in decay rate of 18.1%. Recovery from acidification, due to decreased acidifying emissions and deposition, has led to an increase in the rate of cellulolytic decomposition. This response in a critical ecosystem process offers a potential explanation of one aspect of the limited biological recovery that has been observed so far, an increase in larger bodied predators including fish, which in turn leads to an increase in the length of food chains.     

Long‐term effects of the transient COD concentration on the performance of microbial fuel cells

In this work, the long‐term effects of transient chemical oxygen demands (COD) concentrations over the performance of a microbial fuel cell were studied. From the obtained results, it was observed that the repetitive change in the COD loading rate during 12 h conditioned the behavior of the system during periods of up to 7 days. The main modifications were the enhancement of the COD consumption rate and the exerted current. These enhancements yielded increasing Coulombic efficiencies (CEs) when working with COD concentrations of 300 mg/L, but constant CEs when working with COD concentrations from 900 to 1800 mg/L. This effect could be explained by the higher affinity for the substrate of Geobacter than that of the nonelectrogenic organisms such as Clostridia. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:883–890, 2016     

Long‐term Changes in Bird Communities after Wildfires in the Central Brazilian Amazon

We examined long‐term responses of an Amazonian bird assemblage to wildfire disturbance, investigating how understory birds reacted to forest regeneration 1, 3, and 10 years after a widespread fire event. The bird community was sampled along the Arapiuns and Maró river catchments in central Brazilian Amazonia. Sampling took place in 1998, 2000, and 2008 using mist‐nets in eight plots (four burned, four unburned sites). Species richness did not change significantly in unburned sites. In burned sites, however, we found significantly lower richness in 1998, higher richness in 2000, and similar richness in 2008. Multi‐dimensional scaling ordination showed consistent differences in bird communities both within burned sites sampled in different sampling years, and between burned and unburned sites in all years. Of the 30 most abundant species, 12 had not recovered 10 years after the fires, including habitat specialists such as mixed flocks specialists and ant‐followers. Fire‐disturbance favored three species (two hummingbirds and a manakin) in the short term only. All other species were either favored throughout the study (seven species of omnivores and small insectivores) or did not show a clear response (eight species). In burned sites, we also found significantly lower abundance of species sensitive to disturbances and habitat specialists over the entire study period. Although the bird community seems to be recovering in terms of richness, the overall community composition and abundance of some species in post‐burned and unburned sites remain very different, and have not recovered after 10 years of forest regeneration.     

Long‐term culture optimization of human omentum fat‐derived mesenchymal stem cells

Recent scientific explorations in search of novel sources for autologous transplantation transpired an alternative source of MSCs (mesenchymal stem cells) derived from omentum fat. The scarcity of experimental evidences probing into the biosafety concerns of omentum fat‐derived MSC under prolonged culture conditions limits its applicability as an efficient tool in regenerative medicine. This study, thus, aims to optimize human omentum fat‐derived MSC in four different media [DMEM (Dulbecco's modified Eagle's medium) LG (low glucose), DMEM KO (knock out), α‐MEM (α‐minimal essential media) and DMEM F12] in the facets of phenotypic characterization, growth kinetics, differentiation and karyotyping under prolonged culture. The cells exhibited a similarity in expression profile for the majority of markers with evidential variations in certain markers. The relevance of omentum fat‐derived MSCs became evident from its triumphant differentiation potential and karyotypic stability substantiated even at later passage. The results obtained from growth curve and PDT (population doubling time) lead to optimization of appropriate media for omentum fat‐derived stem cell research, thereby bringing omentum fat into the forefront of regenerative medicine.     

Long‐term hydrogen peroxide exposure potentiates anoikis resistance and anchorage‐independent growth in lung carcinoma cells

Hydrogen peroxide (H₂O₂) is upregulated in tumour microenvironments and may contribute to effects on metastatic cancer cells. This study demonstrates that treatment of lung carcinoma and melanoma cells with H₂O₂ for 14 days results in an induction of anoikis resistance and growth in an anchorage‐independent condition. H₂O₂ exposure increased the Cav‐1 (caveolin‐1) level through an increase of Cav‐1 mRNA with minimal effect on protein degradation. Upregulation of Cav‐1 induced anoikis resistance and facilitated growth in a detached manner. The findings show a novel role of hydrogen peroxide in the regulation of metastatic potential of cancer cells.     

Long‐term decline of native freshwater mussel assemblages in a federally protected river

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Establishment of COS‐JC cells persistently producing archetype JC polyomavirus

JC polyomavirus (JCPyV) is the causative agent of progressive multifocal leukoencephalopathy (PML), a demyelinating disease of the central nervous system in immunocompromised patients. Archetype JCPyV circulates in the human population. There have been several reports of archetype JCPyV replication in cultured cells, in which propagation was not enough to produce high titers of archetype JCPyV. In this study, we carried out cultivation of the transfected cells with archetype JCPyV DNA MY for more than 2 months to establish COS‐7 cells (designated COS‐JC cells) persistently producing archetype JCPyV. Moreover, JCPyV derived from COS‐JC cells was characterized by analyzing the viral propagation, size of the viral genome, amount of viral DNA, production of viral protein, and structure of the non‐coding control region (NCCR). Southern blotting using a digoxigenin‐labeled JCPyV probe showed two different sizes of the JCPyV genome in COS‐JC cells. For molecular cloning, four of five clones showed a decrease in the size of complete JCPyV genome. Especially, clone No. 10 was generated the large deletion within the Large T antigen. On the other hand, the archetype structure of the NCCR was maintained in COS‐JC cells, although a few point mutations occurred. Quantitative PCR analysis of viral DNA in COS‐JC cells indicated that a high copy number of archetype JCPyV DNA was replicated in COS‐JC cells. These findings suggest that COS‐JC cells could efficiently propagate archetype JCPyV MY and offer a useful tool to study persistent infection of archetype JCPyV in a kidney‐derived system.

     

Long‐Term Weight Development in Women: A 15‐Year Follow‐up of the Effects of Pregnancy

Objective: The aim of this study was to evaluate how well prepregnancy BMI, gestational weight gain, and postpartum weight retention predict retention of weight 15 years later among parous women. Research Methods and Procedures: The Stockholm Pregnancy and Women's Nutrition (SPAWN) study is a long‐term follow‐up study of women who delivered children in 1984 to 1985 (n = 2342). The participants initially filled out questionnaires about their eating and exercise habits, social circumstances, etc. before, during, and at 1 year after pregnancy. Anthropometric data were also sampled. Fifteen years later, these women were invited to take part in the follow‐up study. Anthropometric measurements were collected, and similar questions were asked. Five hundred sixty‐three women participated in the SPAWN 15‐year follow‐up study. The sample was divided into groups to examine three presumably critical time periods: 1) overweight and normal weight before pregnancy; 2) low, intermediate, and high weight gainers during pregnancy; and 3) low, intermediate, and high weight retainers at 1 year after pregnancy. Results: The overweight women did not gain more weight during pregnancy or retain more weight at 1 year follow‐up. High weight gainers during pregnancy retained more weight at the 1‐year and the 15‐year follow‐ups. High weight retainers had gained more during pregnancy and retained it at the 15‐year follow‐up. Fifty‐six percent of the high weight gainers during pregnancy ended up in the high weight retainers group. Discussion: Women who are overweight before pregnancy do not have a higher risk of postpartum weight retention than normal weight women. Thus, it is not necessarily the initially overweight woman who should be the target or focus of weight control programs during or after pregnancy. Both high weight gainers and high weight retainers had higher BMI at the 15‐year follow‐up, although only 56% of the high weight gainers during pregnancy were also classified as high weight retainers at the 1‐year follow‐up. Weight retention at the end of the postpartum year predicts future overweight 15 years later.     

Long‐term regulation of local cytokine production following immunization in mice

Vaccines based on pathogen components require adjuvants to enhance the antigen‐specific adaptive immune response. Intramuscular injection of adjuvanted‐vaccines induces inflammatory cytokines and inflammatory nodules at the injection site within 48 hr after injection (Vaccine 2014; 32 : 3393–401). In the present study, long‐term regulation of cytokine production was investigated at 3, 6, 24, and 48 hr, 5 and 7 days, and 2 and 4 weeks after immunization with human papilloma virus (HPV), diphtheria and tetanus toxoids combined with acellular pertussis (DTaP), Haemophilus influenza type B (Hib), and pneumococcal conjugated (PCV) vaccines in mouse models. The second dose was given 4 weeks later, and cytokine profiles were investigated 2, 5, and 7 days after re‐immunization. IL‐1β, IL‐6, granulocyte‐colony stimulating factor (G‐CSF), and MCP‐1 were produced from 3 hr and peaked at 48 hr after immunization with Cervarix in mice. IL‐4, MCP‐1, and TNF‐α peaked at 5 or 7 days after immunization with Gardasil. These cytokines decreased 7 days after immunization with Cervarix and Gardasil. After the second dose, similar responses were observed. Both vaccines induced neutrophil extracellular traps (NET) in inflammatory nodules. The peak amount of IL‐1β, IL‐6, G‐CSF, and MCP‐1 was observed on day 5 of immunization and that of IL‐4 on days 5‐7 of immunization with DTaP, but no increase in IL‐6 and G‐CSF was observed after re‐immunization. A similar response was noted after immunization with PCV13. An inflammatory response is essential for the development of adaptive immunity through the production of inflammatory cytokines.

     

Long‐term spatial memory in Vespula germanica social wasps: the influence of past experience on foraging behavior

Social insects exhibit complex learning and memory mechanisms while foraging. Vespula germanica (Fab.) (Hymenoptera: Vespidae) is an invasive social wasp that frequently forages on undepleted food sources, making several flights between the resource and the nest. Previous studies have shown that during this relocating behavior, wasps learn to associate food with a certain site, and can recall this association 1 h later. In this work, we evaluated whether this wasp species is capable of retrieving an established association after 24 h. For this purpose, we trained free flying individuals to collect proteinaceous food from an experimental plate (feeder) located in an experimental array. A total of 150 individuals were allowed 2, 4, or 8 visits. After the training phase, the array was removed and set up again 24 h later, but this time a second baited plate was placed opposite to the first. After 24 h we recorded the rate of wasps that returned to the experimental area and those which collected food from the previously learned feeding station or the nonlearned one. During the testing phase, we observed that a low rate of wasps trained with 2 collecting visits returned to the experimental area (22%), whereas the rate of returning wasps trained with 4 or 8 collecting visits was higher (51% and 41%, respectively). Moreover, wasps trained with 8 feeding visits collected food from the previously learned feeding station at a higher rate than those that did from the nonlearned one. In contrast, wasps trained 2 or 4 times chose both feeding stations at a similar rate. Thus, significantly more wasps returned to the previously learned feeding station after 8 repeated foraging flights but not after only 2 or 4 visits. This is the first report that demonstrates the existence of long‐term spatial memory in V. germanica wasps.     

Long‐term cytological and histological outcomes in women managed with loop excision treatment under local anaesthetic for high‐grade cervical intraepithelial neoplasia

Y. L. Woo, C. Badley, E. Jackson and R. Crawford Long‐term cytological and histological outcomes in women managed with loop excision treatment under local anaesthetic for high‐grade cervical intraepithelial neoplasia Objective: This study examines the impact of excision margin status after large loop excision of the transformation zone (LLETZ) under local anaesthetic for high‐grade cervical intraepithelial neoplasia (HG‐CIN) on the cytological and histological outcomes up to 5 years after treatment. Methods: Prospective cytological and histological data were obtained by examination of the colposcopy database at Addenbrooke’s Hospital, Cambridge, UK. All women aged between 19 and 50 years who underwent treatment for HG‐CIN by LLETZ under local anaesthetic were included in the study. Patients without follow‐up data were excluded from the study. The excision margin status was correlated with the subsequent cytological and histological outcomes. Results: A series of 967 women with CIN2 and CIN3 underwent LLETZ excision under local anaesthetic. Overall, 42% of women had disease present at the excision margin following LLETZ. Women with CIN3 were more likely than those with CIN2 to have an involved excision margin (P < 0.0001). Cytological recurrence was highest at 12 months (16%) and did not correlate with the CIN grade or excision margin status. Histological recurrence/persistence was also highest at 12 months follow‐up (15%) and this correlated with grade of CIN and margin status (P < 0.0001). Conclusions: Histological recurrence/persistence correlates with grade of CIN and excision margin status. Management of HG‐CIN in an outpatient setting under local anaesthetic is safe, cost effective and yields a favourable long‐term outcome.     

The importance of long‐term social‐ecological research for the future of restoration ecology

In the face of rapid environmental and cultural change, long‐term ecological research (LTER) and social‐ecological research (LTSER) are more important than ever. LTER contributes disproportionately to ecology and policy, evidenced by the greater proportion of LTER in higher impact journals and the disproportionate representation of LTER in reports informing policymaking. Historical evidence has played a significant role in restoration projects and it will continue to guide restoration into the future, but its use is often hampered by lack of information, leading to considerable uncertainties. By facilitating the storage and retrieval of historical information, LTSER will prove valuable for future restoration.     

Long‐term antagonistic effect of increased precipitation and nitrogen addition on soil respiration in a semiarid steppe

Changes in water and nitrogen (N) availability due to climate change and atmospheric N deposition could have significant effects on soil respiration, a major pathway of carbon (C) loss from terrestrial ecosystems. A manipulative experiment simulating increased precipitation and atmospheric N deposition has been conducted for 9 years (2005–2013) in a semiarid grassland in Mongolian Plateau, China. Increased precipitation and N addition interactively affect soil respiration through the 9 years. The interactions demonstrated that N addition weakened the precipitation‐induced stimulation of soil respiration, whereas increased precipitation exacerbated the negative impacts of N addition. The main effects of increased precipitation and N addition treatment on soil respiration were 15.8% stimulated and 14.2% suppressed, respectively. Moreover, a declining pattern and 2‐year oscillation were observed for soil respiration response to N addition under increased precipitation. The dependence of soil respiration upon gross primary productivity and soil moisture, but not soil temperature, suggests that resources C substrate supply and water availability are more important than temperature in regulating interannual variations of soil C release in semiarid grassland ecosystems. The findings indicate that atmospheric N deposition may have the potential to mitigate soil C loss induced by increased precipitation, and highlight that long‐term and multi‐factor global change studies are critical for predicting the general patterns of terrestrial C cycling in response to global change in the future.     

The Long‐Term Management of Obesity with Continuing Pharmacotherapy

Objective: Long‐term, possibly lifetime, use of medications for the management of obesity may be thought to be similar to the use of pharmacotherapy for other chronic diseases such as hypertension or diabetes. Because there have been no systematic studies of this extended use, the experience of eight patients who have used obesity medications in a sustaining manner was studied. Research Methods and Procedures: The clinical characteristics of eight adult patients, each of whom has experience with long‐term (more than 10 years) use of medications for weight loss and weight maintenance, were studied. Results: The clinical experience of these eight patients was analyzed. Each chose to sustain the use of weight management medications for more than 10 years because of perceived benefit, comfort, and the absence of significant side effects. There has been no evidence of the development of tolerance, addiction, or misuse and no adverse events related to the medication. The beneficial effects of the medication have not diminished with time. Discussion: The clinical characteristics of eight patients, each of whom has used obesity pharmacotherapy for more than 10 years, are described. The experience of these eight individuals cannot be generalized to the entire population of overweight or obese patients. It does suggest, however, that some patients respond successfully to this form of therapy and that they will derive value from it for the management of this disease. Efforts should be made to identify these patients, and consideration should be given to the use of chronic medications for the continuing management of obesity.     

Long‐term balanced fertilization increases the soil microbial functional diversity in a phosphorus‐limited paddy soil

The influence of long‐term chemical fertilization on soil microbial communities has been one of the frontier topics of agricultural and environmental sciences and is critical for linking soil microbial flora with soil functions. In this study, 16S rRNA gene pyrosequencing and a functional gene array, geochip 4.0, were used to investigate the shifts in microbial composition and functional gene structure in paddy soils with different fertilization treatments over a 22‐year period. These included a control without fertilizers; chemical nitrogen fertilizer (N); N and phosphate (NP); N and potassium (NK); and N, P and K (NPK). Based on 16S rRNA gene data, both species evenness and key genera were affected by P fertilization. Functional gene array‐based analysis revealed that long‐term fertilization significantly changed the overall microbial functional structures. Chemical fertilization significantly increased the diversity and abundance of most genes involved in C, N, P and S cycling, especially for the treatments NK and NPK. Significant correlations were found among functional gene structure and abundance, related soil enzymatic activities and rice yield, suggesting that a fertilizer‐induced shift in the microbial community may accelerate the nutrient turnover in soil, which in turn influenced rice growth. The effect of N fertilization on soil microbial functional genes was mitigated by the addition of P fertilizer in this P‐limited paddy soil, suggesting that balanced chemical fertilization is beneficial to the soil microbial community and its functions.