Phase Of Recruitment Research Articles

Duox1-derived H2O2 modulates Cxcl8 expression and neutrophil recruitment via JNK/c-JUN/AP-1 signaling and chromatin modifications.

DUOX1-derived hydrogen peroxide (H2O2) and CXCL8 are two key neutrophil chemoattractants. H2O2 is critical at the early phase, whereas CXCL8 plays a key role in the late phases of recruitment, but the crosstalks between the two phases in vivo remain unknown. In this study using zebrafish, we report that H2O2 also contributes to neutrophil recruitment to injuries at the late phase as it induces Cxcl8 expression in vivo through a JNK/c-JUN/AP-1 signaling pathway. However, Erk and NF-κB signaling were not involved in this crosstalk. Strikingly, H2O2 also promotes cxcl8 expression through modulation of histone 3 lysine 4 trimethylation, histone 3 lysine 9 acetylation, and histone 3 lysine 9 trimethylation levels at its promoter. These results explain how early H2O2 signal regulates neutrophil recruitment at all phases, directly via Lyn oxidation or indirectly by modulating cxcl8 gene expression, via the activation of redox-sensitive signaling pathways, and further point out H2O2/DUOX1 as a key drug target for anti-inflammatory therapies.

Analyzing the effects of stromal cells on the recruitment of leukocytes from flow.

Stromal cells regulate the recruitment of circulating leukocytes during inflammation through cross-talk with neighboring endothelial cells. Here we describe two in vitro "vascular" models for studying the recruitment of circulating neutrophils from flow by inflamed endothelial cells. A major advantage of these models is the ability to analyze each step in the leukocyte adhesion cascade in order, as would occur in vivo. We also describe how both models can be adapted to study the role of stromal cells, in this case mesenchymal stem cells (MSC), in regulating leukocyte recruitment. Primary endothelial cells were cultured alone or together with human MSC in direct contact on Ibidi microslides or on opposite sides of a Transwell filter for 24 hr. Cultures were stimulated with tumor necrosis factor alpha (TNFα) for 4 hr and incorporated into a flow-based adhesion assay. A bolus of neutrophils was perfused over the endothelium for 4 min. The capture of flowing neutrophils and their interactions with the endothelium was visualized by phase-contrast microscopy. In both models, cytokine-stimulation increased endothelial recruitment of flowing neutrophils in a dose-dependent manner. Analysis of the behavior of recruited neutrophils showed a dose-dependent decrease in rolling and a dose-dependent increase in transmigration through the endothelium. In co-culture, MSC suppressed neutrophil adhesion to TNFα-stimulated endothelium. Our flow based-adhesion models mimic the initial phases of leukocyte recruitment from the circulation. In addition to leukocytes, they can be used to examine the recruitment of other cell types, such as therapeutically administered MSC or circulating tumor cells. Our multi-layered co-culture models have shown that MSC communicate with endothelium to modify their response to pro-inflammatory cytokines, altering the recruitment of neutrophils. Further research using such models is required to fully understand how stromal cells from different tissues and conditions (inflammatory disorders or cancer) influence the recruitment of leukocytes during inflammation.

Analyzing the Effects of Stromal Cells on the Recruitment of Leukocytes from Flow

Stromal cells regulate the recruitment of circulating leukocytes during inflammation through cross-talk with neighboring endothelial cells. Here we describe two in vitro “vascular” models for studying the recruitment of circulating neutrophils from flow by inflamed endothelial cells. A major advantage of these models is the ability to analyze each step in the leukocyte adhesion cascade in order, as would occur in vivo. We also describe how both models can be adapted to study the role of stromal cells, in this case mesenchymal stem cells (MSC), in regulating leukocyte recruitment. Primary endothelial cells were cultured alone or together with human MSC in direct contact on Ibidi microslides or on opposite sides of a Transwell filter for 24 hr. Cultures were stimulated with tumor necrosis factor alpha (TNFα) for 4 hr and incorporated into a flow-based adhesion assay. A bolus of neutrophils was perfused over the endothelium for 4 min. The capture of flowing neutrophils and their interactions with the endothelium was visualized by phase-contrast microscopy. In both models, cytokine-stimulation increased endothelial recruitment of flowing neutrophils in a dose-dependent manner. Analysis of the behavior of recruited neutrophils showed a dose-dependent decrease in rolling and a dose-dependent increase in transmigration through the endothelium. In co-culture, MSC suppressed neutrophil adhesion to TNFα-stimulated endothelium. Our flow based-adhesion models mimic the initial phases of leukocyte recruitment from the circulation. In addition to leukocytes, they can be used to examine the recruitment of other cell types, such as therapeutically administered MSC or circulating tumor cells. Our multi-layered co-culture models have shown that MSC communicate with endothelium to modify their response to pro-inflammatory cytokines, altering the recruitment of neutrophils. Further research using such models is required to fully understand how stromal cells from different tissues and conditions (inflammatory disorders or cancer) influence the recruitment of leukocytes during inflammation.

The unnoticed effect of a top predator on complex mutualistic ecological interactions

Vertebrates often mediate seed dispersal systems, essential for the maintenance of biodiversity. Some of these acquire a complex multistep process in island environments, where for example a native predatory bird can predate upon a frugivorous vertebrate, dispersing seeds secondarily. These complex mutualistic processes are really threatened by biological invasions especially on islands, due to the particular and intrinsic traits of their biotas. One of the most pernicious invasive mammals is the feral cat, widely introduced on at least 179,000 islands worldwide. Despite the potential impact of disruption of these complex seed dispersal processes, their ecological effects remain largely unknown. Therefore, the main aim of this contribution is to assess the impact of an invasive vertebrate on seed dispersal effectiveness at the crucial phases of plant recruitment: seed damage, viability, and germination. We designed a laborious captivity experiment with lizards and cats to simulate the four potential ways seeds could be dispersed in the wild: (1) control plants, (2) lizard droppings, (3) cat droppings and (4) cat droppings after consuming frugivorous lizards. We considered those four plant species whose seeds were the most abundant in feral cat droppings in all the main habitats of the Canary Islands. The main results indicated that (1) species with thicker seed coat better resisted abrasion caused by the digestive effect of the invasive cats and, (2) native and endemic species with thinner seed coats, that have not evolved with invasive mammals, suffered from a negative effect on seed effectiveness. To our knowledge, this is the first study reporting the potential disruptive impact of secondary seed dispersal systems caused by an invasive predator and one of the scant contributions evaluating seed dispersal effectiveness.

Early netrin-1 expression impairs central nervous system remyelination.

Chronically demyelinated multiple sclerosis (MS) lesions are frequently characterized by scarce undifferentiated oligodendrocyte progenitor cells (OPCs), suggesting the exhaustion of a local OPC pool followed by failure of recruitment and differentiation. Stimulating prompt OPC recruitment following demyelination could improve myelin repair by providing sufficient numbers of remyelinating cells during the repair-permissive period. Understanding mechanisms that determine this process may have important therapeutic implications. We therefore investigated the role of the guidance molecule netrin-1 in OPC recruitment and central nervous system (CNS) remyelination. Netrin-1 expression was analyzed immunohistochemically in different types of MS lesions and in the murine lysolecithin model of demyelination. The influence of netrin-1 on CNS remyelination was examined using gain and loss of function experiments. We show that in MS lesions, astrocytes upregulate netrin-1 expression early during demyelination and netrin-1 receptors are expressed by OPCs. In contrast, in the efficiently repairing lysolecithin model of demyelination (astrocyte-free), netrin-1 expression is absent during early phases and detected concomitant with completion of OPC recruitment. In vitro migration assays demonstrated that netrin-1 is a chemorepellent for migrating adult OPCs. In mouse lesions, antibody-mediated disruption of netrin-1 function at the peak phase of recruitment increased OPC numbers. Conversely, lentiviral-mediated induction of netrin-1 expression prior to OPC recruitment reduced the number of cells recruited and impaired remyelination. Our findings support the conclusion that netrin-1 expression within demyelinating MS plaques blocks OPC recruitment, which with repeated demyelinating episodes contributes to permanent remyelination failure.

Recruitment and abuse of trafficked children in south-west Nigeria

This article examines the recruitment and transportation of internally trafficked children from Benue State in the north-central geo-political zone of Nigeria to Oyo State in the south-western zone of Nigeria. The study is essentially qualitative: with the aid of the snowball sampling technique, in-depth interviews (IDIs) were conducted with drivers, employers and trafficking agents in two recipient communities in Ibadan. The findings show that human rights abuses manifest at the recruitment, transportation and destination phases. The human rights abuses include the recruitment of underage children for domestic work outside their immediate family environments; transportation under inhumane conditions; restriction of movement at traffickers' ‘warehouses’; non-disclosure of amount payable for the services of domestic servants by agents/traffickers; exclusion of domestic servants in wage negotiations; and violence by employers. In view of these, there is a need for the National Agency for the Prohibition of Trafficking in Persons to strengthen its internal trafficking campaign.

Implementing trials of complex interventions in community settings: the USC-Rancho Los Amigos pressure ulcer prevention study (PUPS).

Randomized trials of complex, non-pharmacologic interventions implemented in home and community settings, such as the University of Southern California (USC)-Rancho Los Amigos National Rehabilitation Center (RLANRC) Pressure Ulcer Prevention Study (PUPS), present unique challenges with respect to (1) participant recruitment and retention, (2) intervention delivery and fidelity, (3) randomization and assessment, and (4) potential inadvertent treatment effects. We describe the methods employed to address the challenges confronted in implementing PUPS. In this randomized controlled trial, we are assessing the efficacy of a complex, preventive intervention in reducing the incidence of, and costs associated with, the development of medically serious pressure ulcers in people with spinal cord injury. Individuals with spinal cord injury recruited from RLANRC were assigned to either a 12-month preventive intervention group or a standard care control group. The primary outcome is the incidence of serious pressure ulcers with secondary endpoints including ulcer-related surgeries, medical treatment costs, and quality of life. These outcomes are assessed at 12 and 24 months after randomization. Additionally, we are studying the mediating mechanisms that account for intervention outcomes. PUPS has been successfully implemented, including recruitment of the target sample size of 170 participants, assurance of the integrity of intervention protocol delivery with an average 90% treatment adherence rate, and enactment of the assessment plan. However, implementation has been replete with challenges. To meet recruitment goals, we instituted a five-pronged approach customized for an underserved, ethnically diverse population. In intervention delivery, we increased staff time to overcome economic and cultural barriers to retention and adherence. To ensure treatment fidelity and replicability, we monitored intervention protocol delivery in accordance with a rigorous plan. Finally, we have overcome unanticipated assessment and design concerns related to (1) determining pressure ulcer incidence/severity, (2) randomization imbalance, and (3) inadvertent potential control group contamination. We have addressed the most daunting challenges encountered in the recruitment, assessment, and intervention phases of PUPS. Some challenges and solutions may not apply to trials conducted in other settings. Overcoming challenges has required a multifaceted approach incorporating individualization, flexibility, and persistence, as well as the ability to implement needed mid-course corrections.

The biogeomorphological life cycle of poplars during the fluvial biogeomorphological succession: a special focus on Populus nigra L.

ABSTRACTRiverine ecosystems are recurrently rejuvenated during destructive flood events and vegetation succession starts again. Poplars (i.e. species from Populus genera) respond to hydrogeomorphological constraints, but, in turn, also influence these processes. Thus, poplar development on bare mineral substrates is not exclusively a one‐way vegetative process. Reciprocal interactions and adjustments between poplar species and sediment dynamics during their life cycle lead to the emergence of biogeomorphological entities within the fluvial corridor, such as vegetated islands, benches and floodplains. Based on a review of geomorphological, biological and ecological literature, we have identified and described the co‐constructing processes between riparian poplars and their fluvial environment. We have explored the possibility that the modification of the hydrogeomorphological environment exerted, in particular, by the European black poplar (Populus nigra L.), increases its fitness and thus results in positive niche construction. We focus on the fundamental phases of dispersal, recruitment and establishment until sexual maturity of P. nigra by describing the hierarchy of interactions and the pattern of feedbacks between biotic and abiotic components. We explicitly relate the biological life cycle of P. nigra to the fluvial biogeomorphic succession model by referring to the ‘biogeomorphological life cycle’ of P. nigra. Finally, we propose new research perspectives based on this theoretical framework. Copyright © 2014 John Wiley & Sons, Ltd.

Extracellular ATP mediates the late phase of neutrophil recruitment to the lung in murine models of acute lung injury

Acute lung injury (ALI) is a severe inflammatory condition whose pathogenesis is irrevocably linked to neutrophil emigration to the lung. Activation and recruitment of neutrophils to the lung is mostly attributable to local production of the chemokines. However, much of our understanding of neutrophil recruitment to the lung is based on studies focusing on early time points after initiation of injury. In this study, we sought to evaluate the extended temporal relationship between neutrophil chemotactic factor expression and influx of neutrophils into the lung after intratracheal administration of either LPS or bleomycin. In both models, results demonstrated two phases of neutrophil chemotactic factor expression; first, an early phase characterized by high levels of CXCL1/keratinocyte-derived chemokine, CXCL2/monocyte-inhibitory protein-2, and CXCL5/LPS-induced chemokine expression, and second, a late phase distinguished by increases in extracellular ATP. Furthermore, we show that strategies aimed at either enhancing ATP catabolism (ip ecto-5'-nucleotidase administration) or inhibiting glycolytic ATP production (ip 2-deoxy-d-glucose treatment) reduce extracellular ATP accumulation, limit vascular leakage, and effectively block the late, but not the early, stages of neutrophil recruitment to the lung after LPS instillation. In conclusion, this study illustrates that neutrophil recruitment to the lung is mediated by the time-dependent expression of chemotactic factors and suggests that novel strategies, which reduce extracellular ATP accumulation, may attenuate late neutrophil recruitment and limit lung injury during ALI.

Multimolecular Analysis of Stable Immunological Synapses Reveals Sustained Recruitment and Sequential Assembly of Signaling Clusters

The formation of the immunological synapse between T cells and antigen-presenting cells (APC) begins within minutes of contact and can take hours for full T-cell activation. Although early phases of the synapse have been extensively studied for a select number of proteins, later phases have not yet been examined in detail. We studied the signaling network in stable synapses by measuring the simultaneous localization of 25 signaling and structural molecules over 2 h at the level of individual synapses using multi-epitope ligand cartography (MELC). Signaling proteins including phospho(p)ZAP70, pSLP76, pCD3ζ, and pLAT, along with proteins that influence synapse structure such as F-actin, tubulin, CD45, and ICAM-1, were localized in images of synapses and revealed the multidimensional construction of a mature synapse. The construction of the stable synapse included intense early TCR signaling, a phase of recruitment of structural proteins, and a sustained increase in signaling molecules and colocalization of TCR and pLAT signaling clusters in the center of the synapse. Consolidation of TCR and associated proteins resulted in formation of a small number of discrete synaptic microclusters. Development of synapses and cSMAC composition was greatly affected by the absence of Vav1, with an associated loss in PLCγ1 recruitment, pSLP76, and increased CXCR4. Together, these data demonstrate the use of multi-epitope ligand cartography to quantitatively analyze synapse formation and reveal successive recruitment of structural and signaling proteins and sustained phosphorylation at the mature synapse.

Mast cell and macrophage chemokines CXCL1/CXCL2 control the early stage of neutrophil recruitment during tissue inflammation

AbstractNeutrophil recruitment is an important early step in controlling tissue infections or injury. Here, we report that this influx depends on both tissue-resident mast cells and macrophages. Mice with mast cell deficiency recruit reduced numbers of neutrophils in the first few hours of intraperitoneal lipopolysaccharide (LPS) stimulation. Conversely, in mice with clodronate-ablated macrophages, neutrophils extravasate, but have limited ability to reach the peritoneal fluid. Tissue macrophages synthesize neutrophil chemoattractants CXCL1/CXCL2 (CXC chemokine ligands 1/2) in response to LPS. Mast cells also produce these chemokines of which a proportion are preformed in granules. Release of the granules and new CXCL1/CXCL2 synthesis is Toll-like receptor 4–dependent. Both in vivo studies with blocking monoclonal antibodies and in vitro chemotaxis experiments show the neutrophil response to mast cells and macrophages to be CXCL1/CXCL2-dependent. The data are in keeping with the model that mast cells, optimally positioned in close proximity to the vasculature, initiate an early phase of neutrophil recruitment by releasing the chemoattractants CXCL1/CXCL2. Having arrived within the stimulated tissue, neutrophils penetrate further in a macrophage-dependent manner. Therefore, we demonstrate a positive role for mast cells in tissue inflammation and define how this comes about with contribution from a second tissue cell, the macrophage.

Amperometric Resolution of a Prespike Stammer and Evoked Phases of Fast Release from Retinal Bipolar Cells

The neurotransmitter glutamate is used by most neurons in the brain to activate a multitude of different types of glutamate receptors and transporters involved in fast and relatively slower signaling. Synaptic ribbons are large presynaptic structures found in neurons involved in vision, balance, and hearing, which use a large number of glutamate-filled synaptic vesicles to meet their signaling demands. To directly measure synaptic vesicle release events, the ribbon-type presynaptic terminals of goldfish retinal bipolar cells were coaxed to release a false transmitter that could be monitored with amperometry by placing the carbon fiber directly on the larger synaptic terminal. Spontaneous secretion events formed a unimodal charge distribution, but single spike properties were heterogeneous. Larger events rose exponentially without interruption (τ ∼ 30 μs), and smaller events exhibited a stammer in their rising phase that is interpreted as a brief pause in pore dilation, a characteristic commonly associated with large dense core granule fusion pores. These events were entirely Ca(2+)-dependent. Holding the cells at -60 mV halted spontaneous release; and when the voltage was stepped to >-40 mV, secretion ensued. When stepping the voltage to 0 mV, novel kinetic phases of vesicle recruitment were revealed. Approximately 14 vesicles were released per ribbon in two kinetic phases with time constants of 1.5 and 16 ms, which are proposed to represent different primed states within the population of docked vesicles.

Effect of Type 1 Herpes Simplex Infection of Phenotypic Peculiarities of Human Vascular Endothelial Cells in Culture

We studied the effect of type 1 herpes simplex infection on the production of innate immunity mediators in human vascular endothelial cells in culture. It was found that production of anti-inflammatory cytokines IL-1β, IL.6, and TNF-α in infected cultures depended on the level of their spontaneous production, while IL-8 production was suppressed irrespective of its spontaneous level. Shedding of cell adhesion molecules of early (P-selectin and E-selectin) and late (PECAM-1 and VE-cadherin) phases of leukocyte recruitment depended on individual capacity of human vascular endothelial cell cultures to maintain reproduction of type 1 herpes simples virus. The production of vasodilator NO and vasoconstrictor endothelin-1 by infected cultures also depended on spontaneous synthesis of this transmitter by non-infected cultures.

2826 – Referral of heroin addicts from syringe exchange to evidence-based treatment - a randomized controlled trial

Syringe exchange has been suggested as a potential conduit to treatment for drug addiction. This has been tried in a few US trials, but never in Europe. This study aims to assess effectiveness of a syringe exchange for referral of heroin addicts to evidence-based treatment, and to assess, in an RCT design, the contribution of a case management intervention. Consecutive heroin addicts attending the syringe exchange of Malmö, Sweden, who are willing to participate, are referred to maintenance treatment (methadone or buprenorphine, medication based on clinical assessment and outside the study design), and randomized to either a strength-based case management intervention in order to facilitate referral, or referral-only. If eligible for treatment, patients are initiated on the maintenance treatment after 12 days. Study outcome is successful transfer from syringe exchange to treatment initiation. The study is currently being finalized, and final results (N = 70–75) will be available before presentation at the EPA congress. Pilot data from the first phase of recruitment revealed that among 21 patients, 16 (76%) were willing to join the study. Among them, all 16 successfully showed up for medical assessment, and all but one (94%) successfully initiated medication. Preliminary follow-up until today confirm a similar picture. Pilot data indicate that syringe exchange can be used for transfer to evidence-based treatment in heroin addiction. High rates of patients are successfully transferred to treatment, with or without a facilitating case management intervention. Final results will be presented at the congress.

Effects of environmental and biotic factors on the fluctuations of abundance of Littorina obtusata (Gastropoda: Littorinidae)

To explain periodic fluctuations in abundance of an intertidal flat periwinkle Littorina obtusata, we tested the potential impacts of several key environmental and biotic factors on the population density of this mollusc. The analysis showed that 79% of density variation was due to the changes of the recruitment of the periwinkles and likely caused by intraspecific competition for resources (algae Fucus vesiculosus) between the recruits and the older molluscs under the conditions of depleted habitat capacity. The cyclical changes in L. obtusata density result from the alternating periods of high and low recruitment. High recruitment is observed when the abundance of mature periwinkles is relatively low and enough resources are available to insure high survival of the recruits. The duration of high recruitment periods (approximately 3 years) is determined by the maturation time of the periwinkles. As the recruits mature, the density of adult periwinkles increases and the subsequent recruitment decreases. The duration of the low recruitment phases (an average of 3–4 years) appear linked to the longevity of mature L. obtusata. As the adults age and die out, their density declines and the release of resources leads to an increase of recruitment heralding the beginning of the next cycle.

Reactions to Recruitment Web Sites: Visual and Verbal Attention, Attraction, and Intentions to Pursue Employment

We investigate job seeker visual and verbal attention, and perceptions regarding company web sites in the applicant generation phase of recruitment. We report three studies using varied methodological approaches including eye-tracking, verbal protocol analysis (VPA), and survey data. Eye-tracking results suggest Web-based job seekers focus visual attention on information containing hyperlinks and on text more than graphic images or navigation tools. VPA suggests Web-based job seekers focus verbal attention on content more than design, especially job opening information. Survey results suggest content, design, and communication features are all related to applicant attraction. Design explains the most incremental variance in web site evaluation, while perceptions of communication features explain the most incremental variance in attitude toward the organization and intentions to pursue employment. We provide multi-method evidence concerning features that attract applicant visual and verbal attention, and influence attraction and intentions to pursue employment. The findings also provide practical implications for designing recruitment web sites. We report three methodologically distinct perspectives on an important and timely issue: Web-based recruitment. We are aware of no other psychomotor eye-tracking studies in the recruitment literature, and only one other VPA. Combining multiple methods in this way provides unique perspective.

Successful Minority Recruitment and Adherence in Physical Activity Internet-Based Research: The WIN Study

Researchers studying physical activity often face challenges dealing with recruitment and resources, particularly when conducting longitudinal Internet-based research. Commonly raised methodological problems such as minority recruitment, participant commitment, and participant-staff involvement are addressed through a theoretically driven recruitment and adherence protocol in The Women's Exercise Injuries: Incidence and Risk Factors (WIN) Internet-based study. The objectives of this paper were to review and suggest solutions to problems of: (1) low recruitment of diverse samples, (2) low adherence, and (3) staffing needs. We recruited 1303 community-dwelling women and followed them through a multiple-phase, longitudinal, Internet-based study. Recruitment and adherence data were analyzed through descriptive methods and logistic regressions to examine participant adherence and sociodemographic factors and predictors of who entered the long-term phase of the study. We successfully retained 71.6% of the sample through 4 recruitment phases. Twenty-seven percent of the initially recruited sample was racial/ethnically diverse, 24% began the long-term phase, and 23% completed. Several strategies to enhance participant commitment were successfully used during the practice phase, providing a successful, low staff to participant ratio. Logistic regression indicated being married, being older, and having greater Internet skills were predictive of successfully entering the long-term phase of the study. Recruitment and compliance protocols were successful in meeting overall and racial/ethnic enrollment and recruitment goals. The theoretically based practice phase techniques were successful in re-engaging noncompliant participants. Strategies for minority enrollment and compliance are evaluated.

Home ovulation tests and stress in women trying to conceive: a randomized controlled trial.

STUDY QUESTIONDoes the use of a digital home ovulation test have any effect on the level of stress in women seeking to conceive?SUMMARY ANSWERNo difference was found in levels of stress between women using digital ovulation tests to time intercourse compared with women who were trying to conceive without any additional aids: in addition, their use did not negatively impact time to conception in users but may provide additional benefits, including an increased understanding of the menstrual cycle, reassurance and confidence in focusing conception attempts to the correct time in the cycle.WHAT IS KNOWN ALREADYIt has been suggested that timing of intercourse in such a way that it coincides with ovulation by using ovulation tests can lead to emotional distress; however, no study has been conducted to investigate this hypothesis specifically, until now.STUDY DESIGN, SIZE AND DURATIONThe study was performed over two complete menstrual cycles as a prospective, randomized, controlled trial including quantitative and qualitative methods. The intervention (test) group were given digital ovulation tests to time intercourse to the most fertile time of the cycle and the control group were provided with the current National Institute for Health and Clinical Excellence guidelines for increasing the chances of conception (intercourse every 2–3 days) and asked not to use any additional methods to time when ovulation occurs.PARTICIPANTS/MATERIALS, SETTING AND METHODSA total of 210 women who were seeking to conceive were recruited from the general UK population. A total of 115 women were randomized to the test group and 95 to the control group through block randomization. The positive and negative affect schedule (PANAS) and the Perceived Stress Scale (PSS) were used to measure subjective stress levels, the Short-Form 12 health survey was used as a measure of general health and well-being and urine samples were measured for biochemical markers of stress including urinary cortisol. Qualitative data were collected in the form of a telephone interview upon study completion.MAIN RESULTS AND THE ROLE OF CHANCEThere was no evidence for a difference either in total stress as measured using the PSS or in total positive or negative affect using the PANAS questionnaire between the test and control groups at any time point for the duration of the study. During cycle 1, for example, on Day 6, the difference in total stress score (test–control) was −0.62 [95% confidence interval (CI) −2.47 to 1.24] and on the day of the LH surge, it was 0.53 (95% CI −1.38 to 2.44). In addition, no correlation was observed between time trying to conceive and levels of stress, or between age and levels of stress, and no evidence was found to show that stress affected whether or not a pregnancy was achieved. There is also no evidence that the biochemistry measurements are related to whether a pregnancy was achieved or of a difference in biochemistry between the treatment groups. The use of digital ovulation tests did not negatively affect time to conception and with an adequately sized study, could potentially show improvement. To ensure that the results of this study were not affected by chance, we used a number of different methods for measuring stress, each of which had been independently validated.LIMITATIONS AND REASONS FOR CAUTIONRandomization occurred before the start of the study because of the need to provide the ovulation tests in readiness for Day 6 of the first cycle. As a consequence, a number of women fell pregnant during this period (22 and 13 in the test and control groups, respectively). A further 15 women were either lost to follow-up or withdrew consent prior to study start. Pregnancy rate was higher overall in the test group, so to ensure that there were sufficient data from women who failed to become pregnant in the test group, we implemented an additional biased recruitment. This second cohort may have been different from the first, although no significant differences were observed between the two phases of recruitment for any of the information collected upon admission to the study.WIDER IMPLICATIONS OF THE FINDINGSWomen who seek medical advice while trying to conceive should not be discouraged by health care professionals from using digital ovulation tests in order to time intercourse. The cohort of women recruited to this study initially had no evidence of infertility and were looking to conceive in a non-medical setting. A separate study to assess the impact of home ovulation tests in a subfertile population would be of interest and complementary to the present study.STUDY FUNDING/COMPETING INTERESTSThis study was funded by SPD Swiss Precision Diagnostics, GmbH, manufacturer of Clearblue® pregnancy and ovulation tests. SPD Development Company Ltd is a wholly owned subsidiary of SPD Swiss Precision Diagnostics GmbH; together referred to as SPD.TRIAL REGISTRATION NUMBERNCT01084304 (www.clinicaltrials.gov).

Estradiol receptors agonists induced effects in rat intestinal microcirculation during sepsis

The steroid hormone estradiol is suggested to play a protective role in intestinal injury during systemic inflammation (sepsis). Our aim was to determine the effects of specific estradiol receptor (ER-α and ER-ß) agonists on the intestinal microcirculation during experimental sepsis. Male and sham ovariectomized female rats were subjected to sham colon ascendens stent peritonitis (CASP), and they were compared to male and ovariectomized female rats underwent CASP and either estradiol receptor α (ER-α) agonist propyl pyrazole triol (PPT), estradiol receptor ß (ER-ß) agonist diarylpropiolnitrile (DPN), or vehicle treatment. Intravital microscopy was performed, which is sufficiently sensitive to measure changes in the functional capillary density (FCD) as well as the major steps in leukocyte recruitment (rolling and adhesion). The leukocyte extravasations were also quantified by using histological paraffin sections of formalin fixed intestine. We found that either DPN (ER-β) or PPT (ER-α) significantly reduced (P<0.05) sepsis-induced leukocyte-endothelial interaction (rolling, adherent leukocytes and neutrophil extravasations) and improved the intestinal muscular FCD. [PPT: Female; Leukocyte rolling (n/min): V3 3.7±0.7 vs 0.8±0.2, Leukocyte adhesion(n/mm2): V3 131.3±22.6 vs 57.2±13.5, Neutrophil extravasations (n/10000μm2): 3.1±0.7 vs 6 ±1. Male; Leukocyte adhesion (n/mm2): V1 154.8±19.2 vs 81.3±11.2, V3 115.5±23.1 vs 37.8±12]. [DPN: Female; neutrophil extravasations (n/10000μm2) 3.8±0.6 vs 6 ±1. Male; Leukocyte adhesion (n/mm2) V1 154.8±19.2 vs 70±10.5, V3 115.5±23.1 vs 52.8±9.6].Those results suggest that the observed effects of estradiol receptors on different phases of leukocytes recruitment with the improvement of the functional capillary density could partially explain the previous demonstrated salutary effects of estradiol on the intestinal microcirculation during sepsis. The observed activity of this class of compounds could open up a new avenue of research into the potential treatment of sepsis.

Survey Methods and Aging Research in an Arab Sociocultural Context--A Case Study from Beirut, Lebanon

In Arab countries, the proportion of older adults is rapidly increasing, highlighting the need to conduct research on factors that influence aging. We describe the context-specific challenges faced and the solutions negotiated during the conduct of a survey study on family relations and aging in Greater Beirut, Lebanon. Drawing on the experience of a recently completed survey study, we reflect on the context-specific challenges faced and the solutions negotiated during the phases of questionnaire construction, interviewer training, sampling, and participant recruitment as a means to contribute to the growing area of cross-cultural survey research. The social context of family relations influenced the nature of questions that can be included to obtain valid information. The unavailability of demographic data and the presence of cultural norms that promote deference to older adults also presented methodological challenges to the sampling and recruitment of older adults. We provided illustrative examples on the importance of learning about a country's social and cultural contexts, and the necessity of exercising flexibility in decision making to ensure the collection of valid data and the successful completion of the study. Lessons learned inform elements of the research process in an Arab country, as well as bring to light unusual, yet generalizable, circumstances that will inform experiences in other cultural settings.