Genome-wide Scan of Dental Fear and Anxiety Nominates Novel Genes

Dental care-related fear and anxiety (DFA) is prevalent, affects oral health care utilization, and is related to poor oral health and decreased quality of life. In addition to learned and cultural factors, genetics is hypothesized to contribute to DFA. Therefore, we performed a genome-wide association study to identify genetic variants contributing to DFA. Adult and adolescent participants were from 4 cohorts (3 from the US-based Center for Oral Health Research in Appalachia, n = 1,144, 1,164, and 535, and the UK-based Avon Longitudinal Study of Parents and Children [ALSPAC], n = 2,078). Two self-report instruments were used to assess DFA: the Dental Fear Survey (US cohorts) and Corah's Dental Anxiety Scale (ALSPAC). Genome-wide scans were performed for the DFA total scores and subscale scores (avoidance, physiological arousal, fear of dental treatment-specific stimuli), adjusting for age, sex, educational attainment, recruitment site, and genetic ancestry. Results across cohorts were combined using meta-analysis. Heritability estimates for DFA total and subscale scores were similar across cohorts and ranged from 23% to 59%. The meta-analysis revealed 3 significant (P < 5E-8) associations between genetic loci and 2 DFA subscales: physiological arousal and avoidance. Nearby genes included NTSR1 (P = 3.05E-8), DMRTA1 (P = 4.40E-8), and FAM84A (P = 7.72E-9). Of these, NTSR1, which was associated with the avoidance subscale, mediates neurotensin function, and its deficiency may lead to altered fear memory in mice. Gene enrichment analyses indicated that loci associated with the DFA total score and physiological arousal subscale score were enriched for genes associated with severe and persistent mental health (e.g., schizophrenia) and neurocognitive (e.g., autism) disorders. Heritability analysis indicated that DFA is partly explained by genetic factors, and our association results suggested shared genetic underpinnings with other psychological conditions.

P-259 Cumulus cells mitochondrial membrane potential as a marker of oocyte competence in assisted reproduction

Study question

Is mitochondrial function of human Cumulus-oophurus Cells (hCCs) an important non-invasive biomarker for oocyte competence and a predictor of in vitro fertilisation (IVF) outcomes?

Summary answer

Advanced maternal age of women undergoing IVF is characterized by an impairment in cumulus cell mitochondrial function.

What is known already

The increasing delay of childbearing has led to urgent development of new non-invasive biomarkers of oocyte competency. Aging is a complex process that includes impairment of mitochondrial function and metabolic activity, increase of oxidative stress, alteration in the activity of several cell-signaling systems.

A great candidate to monitoring oocyte quality is the hCCs. During folliculogenesis there is an intense bidirectional communication between oocyte and its follicular cells. During oogenesis, CCs supply the oocyte with energy substrates and essential nutrients. Age-related mitochondrial dysfunction in hCCs was described to adversely affect oocyte growth and development.

Study design, size, duration

The objective of this study was to characterise the mitochondrial membrane potential (Δψm) of hCCs provided from patients undergoing ICSI (intracytoplasmic sperm injection) or oocyte cryopreservation in the Reproductive Medicine Unit of CHUC (Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal) between July and December 2021, to establish a predictive biomarker of oocyte competency and successful IVF outcomes.

Participants/materials, setting, methods

hCCs, collected from cumulus-oocyte complexes of 53 patients, were incubated with tetramethylrhodamine methyl ester (TMRM - 50 nM), MitoTracker Green (MTG 100 nM) and Hoechst (5µg/mL). Briefly, TMRM, due to its positive charge, accumulates within the mitochondria in a ΔΨm-depend manner, and emits red fluorescence. On the other hand, MTG is green-fluorescent mitochondrial dye which appears to localize in mitochondria regardless of Δψm. Therefore, the red/green fluorescence ratio can be measured as mitochondrial activity outcome.

Main results and the role of chance

The 53 patients studied were divided in two age groups (27 patients with &lt;35 and 26 with ≥ 35 years old). A decrease in hCCs Δψm of women with advanced maternal age (≥35 y) compared with hCCs recovered from women with &lt;35 was observed (P = 0.001). No differences were found in CCs Δψm in terms of infertility cause, body mass index and social habits (e.g., smoking) (P &gt; 0.05). We also investigated if Δψm can be an effective indicator of clinical outcomes in IVF techniques; however, no correlation was observed between Δψm and oocyte maturation, fertilization, D3 embryo development and blastocyst development rates.

Our preliminary data strongly support the idea that advanced reproductive age of women undergoing IVF is accompanied by impaired cumulus cell mitochondrial function.

Limitations, reasons for caution

More data is needed to be collected to support our preliminary results, such as increasing the sample size, as well as better characterisation of the mitochondrial function in hCCs.

Wider implications of the findings

This knowledge opens a new window of opportunities in the development of new strategies to mitigate the effects of oocyte aging on (in)fertility, through clinical therapies, such as enhancing the mitochondrial function in hCCs.

Trial registration number

-

Prognostic significance of anemia in women with suspected ischemia, an insight from the women ischemia syndrome evaluation study (WISE)

Background

Anemia is associated with adverse cardiovascular outcomes in patients with myocardial infarction and congestive heart failure. Anemia is more prevalent in women. We investigated the prognosis of anemia in women with suspected ischemic heart disease.

Purpose

To study if hemoglobin levels at baseline in women with symptoms of ischemia predicts long term all-cause mortality and major adverse cardiac events.

Methods

We studied 885 women enrolled in WISE (1997–2001) undergoing clinically indicated coronary angiography for suspected ischemia. Anemia was defined as hemoglobin (Hb) level &lt;12g/dL. Major adverse cardiovascular event (MACE) included all-cause death, nonfatal myocardial infarction, stroke and heart failure hospitalization. Cox regression models and Kaplan-Meier methods were was used.

Results

Overall, 885 women, mean age 58.4±11.7 years, 21.1% and anemia were followed for 6.8 years. Anemic women had higher creatinine, history of diabetes mellitus, hypertension and CHF (p&lt;0.05), but not obstructive coronary artery disease compared to non-anemia women (p=0.97). Anemic women had higher all-cause mortality and MACE (Figure). In multivariate analysis, anemia was independently associated with increased MACE risk (hazard ratio (HR): 1.5, 95% confidence interval [1.11- 2.01, p=0.007]) but not all-cause mortality (HR: 1.2 [0.84–1.72, p=0.30]).

Conclusions

Among women evaluated for symptoms of ischemia, anemia is associated with and independently predicts MACE. Further research targeting anemia treatment in women to mitigate these adverse outcomes is warranted.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): NIH USA

P–452 The challenge of ovarian tissue culture: 2D versus 3D

Study question

Does an alginate matrix scaffold improve ovarian tissue culture?

Summary answer

Ovarian tissue culture within an alginate scaffold has no advantage over conventional culture, being more time consuming and less reproductible

What is known already

Cryopreservation of ovarian tissue is a powerful technique for preserving female fertility, as it can restore fertility and endocrine function. Several studies have been carried out aiming to increase the longevity of the transplant and decrease the risk of reimplantation of neoplastic cells. For in vitro follicle culture, recent research has shifted from two dimensional (2D) toward the use of three-dimensional (3D) structures. The use of a matrix maintains the architecture and mimics in vivo conditions, with a variable access to oxygen and nutrients. This bridges the gap between conventional cell culture and animal models.

Study design, size, duration

Ovarian tissue fragments were divided into 2 groups: conventional culture (2D culture) and culture using an alginate matrix scaffold (3D culture). Tissue was evaluated at four time-points: immediately after thawing and after 24, 48 and 72 hours of culture.

Participants/materials, setting, methods

Rat ovarian tissue was cryopreserved and thawed with validated protocols. Follicular analysis was conducted after haematoxylin and eosin staining, regarding density, classification and degeneration. Tissue viability was assessed using lactate dehydrogenase (LDH) levels in supernatants and histological score. Three parameters were considered, namely, interstitial oedema, follicular cell degeneration and percentage of tissue in necrosis. Apoptosis was assessed by caspase 3 immunostaining. Proliferating cells were identified using Ki67 immunohistochemical labelling.

Main results and the role of chance

Follicular density, cell proliferation and apoptosis both in follicles and stroma was similar in both culture conditions. Stromal cells proliferation was stable in conventional culture but decreased in 3D culture (p = 0.001), which can be explained by the rigidity of alginate matrix. At 24 hours of culture, cytotoxicity was lower in the 3D model (p = 0.006), due to low levels of LDH in the supernatant, that may be related to retention within the matrix. As culture time increased cytotoxicity seemed to be similar. Degradation of the tissue was suggested by the histological score analysis of tissue during 72 hours of culture. Tissue injury was greater (p = 0.01) in 3D culture due to higher interstitial oedema (p = 0.017) and tissue necrosis (p = 0.035). In the interior of the alginate scaffold, the bioavailability of oxygen and nutrients may be limited, affecting cell survival over time and conditioning higher level of necrosis and release of intracellular content.

Limitations, reasons for caution

There are two major limitations that should be addressed in future research, namely the study of the tissue-matrix interactions and culture medium supplementation to decrease follicular atresia.

Wider implications of the findings: There is no advantage in the use of an alginate matrix scaffold for ovarian tissue culture, as it is more time consuming, difficult to perform and less reproductible.

Trial registration number

Not applicable

Transferrin-functionalized lipid nanoparticles for curcumin brain delivery

Curcumin is an anti-inflammatory and antioxidant compound with potent neuroprotective activity. Due to its poor water solubility, low bioavailability, rapid elimination and the challenges for crossing and transposing the blood-brain barrier (BBB), solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) loaded with curcumin were successfully produced and functionalized with transferrin, in order to mediate the transport of these particles through the BBB endothelium to the brain. The nanosystems revealed Z-averages under 200 nm, polydispersity index below 0.2 and zeta potential around -30 mV. Curcumin encapsulation around 65 % for SLNs and 80 % for NLCs was accomplished, while the functionalized nanoparticles presented a value around 70-75 %. A stability study revealed these characteristics remained unchanged for at least 3 months. hCMEC/D3 cells viability was firstly analysed by MTT and LDH assays, respectively, and a concentration of 10 μM of curcumin-loaded nanoparticles were then selected for the subsequent permeability assay. The permeability study was conducted using transwell devices with hCMEC/D3 cells monolayers and a 1.5-fold higher permeation of curcumin through the BBB was verified. Both SLNs and NLCs are promising for curcumin brain delivery, protecting the incorporated curcumin and targeting to the brain by the addition of transferrin to the nanoparticles surface.

Targeted nanostructured lipid carriers for doxorubicin oral delivery

The treatment with anticancer drugs remains a challenge, as available drugs still entail the risk of deleterious off-target effects. The present study describes folic acid conjugated nanostructured lipid carriers (NLCs) as an effective doxorubicin delivery approach targeted to breast cancer cells. Two distinct NLCs formulations were designed and optimized leading to an encapsulation efficiency over than 65%. Cytotoxic and targeting potential of NLCs were studied in vitro, using MDA-MB-231 cell line. Results showed an enhanced cellular uptake of conjugated NLCs. In vitro release studies, mimicking the path in the body after oral administration, show that all formulations would reach the tumor microenvironment bearing 50% of the encapsulated doxorubicin. Moreover, NLCs demonstrated storage stability at 25 °C for at least 42 days. Overall, results revealed that the developed NLCs enable the possibility of oral administration and are a promising approach for the targeted delivery of doxorubicin to breast cancer cells.

Role of physical fitness in the obesity paradox. Long-term major adverse cardiovascular events in the Women's Ischemia Syndrome Evaluation (WISE)

Background

Emerging data suggests there is an “obesity paradox” where obesity may be protective against cardiovascular morbidity and mortality in patients with cardiovascular disease. However, weight status primarily assessed through body mass index (BMI) is limited in its ability to discern contributions from fat vs. lean muscle mass. Most studies on BMI have not accounted for physical fitness, which is a known modifier of weight status and a potential mediator of effects of obesity on major adverse cardiovascular events (MACE).

Purpose

To investigate the relationship between BMI and physical fitness, measured by self-reported Duke Activity Status Index (DASI) score, with long-term MACE in women evaluated for suspected myocardial ischemia.

Methods

The National Heart, Lung, and Blood Institute Women's Ischemia Syndrome Evaluation (WISE) study is a multicenter prospective cohort study. From 1996–2000, 936 women were enrolled at the time of clinically indicated coronary angiography and assessed with a median follow up of 5.8 (range 0–9 years) for MACE. MACE was defined as a composite of death, nonfatal myocardial infarction, stroke, or congestive heart failure. Proportional hazards regression was used to estimate adjusted hazard ratios of MACE in relation to metabolic status and physical fitness. DASI scores ≥25, equivalent to ≥7 metabolic equivalents [METs]) was used as cut point to define high physical fitness, in our prior studies DASI &gt;25 approximates completion of the second stage of a Bruce treadmill protocol.

Results

Among the 899 women with complete data, 69.5% had low physical fitness (DASI scores &lt;25), 34.9% overweight (BMl ≥25 to 30), 40.5% obese (BMI ≥30). In fit women, obesity was associated with lower hazard ratio for MACE (HR 0.64, p=0.01); while low fitness in normal weight women was associated with 60% excess risk of MACE (HR 1.61, p=0.01) (Figure 1).

Conclusions

Among women undergoing coronary angiography for suspected myocardial ischemia, obesity was inversely related with long-term MACE in physically fit women. Our findings suggest that physical fitness may play a role in the obesity paradox. These results support the inclusion of fitness in understanding the relations between body weight and long-term MACE. The DASI is a simple, self reported tool that can identify higher-risk symptomatic women and should be considered in future investigations and routine examination of normal, overweight and obese women.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): U01 HL064829

Influence of land use and host species on parasite richness, prevalence and co-infection patterns

Tropical forests are experiencing increasing impacts from a multitude of anthropogenic activities such as logging and conversion to agricultural use. These perturbations are expected to have strong impacts on ecological interactions and on the transmission dynamics of infectious diseases. To date, no clear picture of the effects of deforestation on vector-borne disease transmission has emerged. This is associated with the challenge of studying complex systems where many vertebrate hosts and vectors co-exist. To overcome this problem, we focused on an innately simplified system - a small oceanic island (São Tomé, Gulf of Guinea). We analyzed the impacts of human land-use on host-parasite interactions by sampling the bird community (1735 samples from 30 species) in natural and anthropogenic land use at different elevations, and screened individuals for haemosporidian parasites from three genera (Plasmodium, Haemoproteus, Leucocytozoon). Overall, Plasmodium had the highest richness but the lowest prevalence, while Leucocytozoon diversity was the lowest despite having the highest prevalence. Interestingly, co-infections (i.e. intra-host diversity) involved primarily Leucocytozoon lineages (95%). We also found marked differences between bird species and habitats. Some bird species showed low prevalence but harbored high diversity of parasites, while others showed high prevalence but were infected with fewer lineages. These infection dynamics are most likely driven by host specificity of parasites and intrinsic characteristics of hosts. In addition, Plasmodium was more abundant in disturbed habitats and at lower elevations, while Leucocytozoon was more prevalent in forest areas and at higher elevations. These results likely reflect the ecological requirements of their vectors: mosquitoes and black flies, respectively.

Quercetin lipid nanoparticles functionalized with transferrin for Alzheimer's disease

Quercetin was encapsulated in lipid nanoparticles (SLN and NLC) to take advantage of its neuroprotective properties in Alzheimer's disease. The nanoparticles were functionalized with transferrin to facilitate the passage across the blood-brain barrier through the transferrin receptors overexpressed in brain endothelial cells. NMR and FTIR confirmed the functionalization of the nanoparticles with transferrin. TEM results showed all nanoparticles presented spherical morphology. Nanoparticles exhibited size around 200 nm and zeta potential values higher than -30 mV. Quercetin entrapment efficiency was around 80-90%. LDH cytotoxicity assays in hCMEC/D3 cell line demonstrated that even for the highest concentration (30 μM) nanoparticles did not reveal cytotoxicity after 4 h of incubation. Permeability studies across hCMEC/D3 cell monolayers showed NLC permeate more the blood-brain barrier, while amyloid-beta studies demonstrated NLC-transferrin have the capacity to inhibit fibril formation. Nanoparticles seem to be suitable for brain applications, mainly for Alzheimer's disease due to inhibition of amyloid-beta aggregation.

Optimization of nanostructured lipid carriers for Zidovudine delivery using a microwave-assisted production method

An adapted methodology for obtaining lipid nanoparticles that only uses the microwave reactor in the synthesis process was developed. The method has the following features: one-pot, one-step, fast, practical, economical, safe, readiness of scaling-up, lack of organic solvents and production of nanoparticles with low polydispersity index (PDI) (below 0.3). This new method was applied for the development of nanostructured lipid carriers (NLC) loaded with a hydrophilic drug, the antiretroviral agent zidovudine (AZT). The aim of the present work was to develop, evaluate and compare optimized NLC formulations produced by two different methods - hot ultrasonication and microwave-assisted method. The development and optimization of the NLC formulations were supported by a Quality by Design (QbD) approach. All formulations were physicochemically characterized by the same parameters. The optimized formulations presented a suitable profile for oral administration (particle size between 100 and 300 nm, PDI < 0.3 and negative zeta potential >-20 mV). Furthermore, the morphologies assessed by TEM showed spherical shape and confirmed the results obtained by DLS. Both AZT loaded formulations were physically stable for at least 45 days and non-toxic on Jurkat T cells. Drug release studies showed a controlled release of AZT under gastric and plasma-simulated conditions.

Effects of resveratrol on the structure and fluidity of lipid bilayers: a membrane biophysical study

Resveratrol is a natural active compound which has been attracting increasing interest due to its several pharmacological effects in cancer prevention, cardiovascular protection and treatment of neurodegenerative disorders and diabetes. The current work investigates how resveratrol affects membrane order and structure, gathering information determined by X-ray scattering analysis, derivative spectrophotometry, fluorescence quenching and fluorescence anisotropy studies. The results indicate that resveratrol is able to be incorporated into DMPC liposome model systems, either fluidizing or stiffening the bilayer, which largely depends on the membrane fluidity state. These findings suggest that the effects of resveratrol resemble cholesterol action on biological membranes, thereby contributing to the regulation of cell membrane structure and fluidity, which may influence the activity of transmembrane proteins and hence control the cell signaling pathways. The regulation of a number of cellular functions, thus may contribute to the pharmacological and therapeutic activities of this compound, explaining its pleiotropic action.

The potential for tree planting strategies to reduce local and regional ecosystem impacts of agricultural ammonia emissions

Trees are very effective at capturing both gaseous and particulate pollutants from the atmosphere. But while studies have often focussed on PM and NOx in the urban environment, little research has been carried out on the tree effect of capturing gaseous emissions of ammonia in the rural landscape. To examine the removal or scavenging of ammonia by trees a long-range atmospheric model (FRAME) was used to compare two strategies that could be used in emission reduction policies anywhere in the world where nitrogen pollution from agriculture is a problem. One strategy was to reduce the emission source strength of livestock management systems by implementing two 'tree-capture' systems scenarios - tree belts downwind of housing and managing livestock under trees. This emission reduction can be described as an 'on-farm' emission reduction policy, as ammonia is 'stopped' from dispersion outside the farm boundaries. The second strategy was to apply an afforestation policy targeting areas of high ammonia emission through two planting scenarios of increasing afforestation by 25% and 50%. Both strategies use trees with the aim of intercepting NH3 emissions to protect semi-natural areas. Scenarios for on-farm emission reductions showed national reductions in nitrogen deposition to semi-natural areas of 0.14% (0.2 kt N-NHx) to 2.2% (3.15 kt N-NHx). Scenarios mitigating emissions from cattle and pig housing gave the highest reductions. The afforestation strategy showed national reductions of 6% (8.4 kt N-NHx) to 11% (15.7 kt N-NHx) for 25% and 50% afforestation scenarios respectively. Increased capture by the planted trees also showed an added benefit of reducing long range effects including a decrease in wet deposition up to 3.7 kt N-NHx (4.6%) and a decrease in export from the UK up to 8.3 kt N-NHx (6.8%).

Complexes of fluconazole with sodium p-sulfonatocalix[n]arenes: characterization, solubility and antifungal activity

Aiming at providing new formulations capable of improving the biopharmaceutical properties of fluconazole, we studied the formation of host–guest complexes of this antifungal agent with water-soluble sodium p-sulfonatocalix[n]arenes.

Optimization of the magnetoelectric response of poly(vinylidene fluoride)/epoxy/Vitrovac laminates

The effect of the bonding layer type and piezoelectric layer thickness on the magnetoelectric (ME) response of layered poly(vinylidene fluoride) (PVDF)/epoxy/Vitrovac composites is reported. Three distinct epoxy types were tested, commercially known as M-Bond, Devcon, and Stycast. The main differences among them are their different mechanical characteristics, in particular the value of the Young modulus, and the coupling with the polymer and Vitrovac (Fe39Ni39Mo4Si6B12) layers of the laminate. The laminated composites prepared with M-Bond epoxy exhibit the highest ME coupling. Experimental results also show that the ME response increases with increasing PVDF thickness, the highest ME response of 53 V·cm(-1)·Oe(-1) being obtained for a 110 μm thick PVDF/M-Bond epoxy/Vitrovac laminate. The behavior of the ME laminates with increasing temperatures up to 90 °C shows a decrease of more than 80% in the ME response of the laminate, explained by the deteriorated coupling between the different layers. A two-dimensional numerical model of the ME laminate composite based on the finite element method was used to evaluate the experimental results. A comparison between numerical and experimental data allows us to select the appropriate epoxy and to optimize the piezoelectric PVDF layer width to maximize the induced magnetoelectric voltage. The obtained results show the critical role of the bonding layer and piezoelectric layer thickness in the ME performance of laminate composites.

Integrating health and environmental impact analysis

Scientific investigations have progressively refined our understanding of the influence of the environment on human health, and the many adverse impacts that human activities exert on the environment, from the local to the planetary level. Nonetheless, throughout the modern public health era, health has been pursued as though our lives and lifestyles are disconnected from ecosystems and their component organisms. The inadequacy of the societal and public health response to obesity, health inequities, and especially global environmental and climate change now calls for an ecological approach which addresses human activity in all its social, economic and cultural complexity. The new approach must be integral to, and interactive, with the natural environment. We see the continuing failure to truly integrate human health and environmental impact analysis as deeply damaging, and we propose a new conceptual model, the ecosystems-enriched Drivers, Pressures, State, Exposure, Effects, Actions or 'eDPSEEA' model, to address this shortcoming. The model recognizes convergence between the concept of ecosystems services which provides a human health and well-being slant to the value of ecosystems while equally emphasizing the health of the environment, and the growing calls for 'ecological public health' as a response to global environmental concerns now suffusing the discourse in public health. More revolution than evolution, ecological public health will demand new perspectives regarding the interconnections among society, the economy, the environment and our health and well-being. Success must be built on collaborations between the disparate scientific communities of the environmental sciences and public health as well as interactions with social scientists, economists and the legal profession. It will require outreach to political and other stakeholders including a currently largely disengaged general public. The need for an effective and robust science-policy interface has never been more pressing. Conceptual models can facilitate this by providing theoretical frameworks and supporting stakeholder engagement process simplifications for inherently complex situations involving environment and human health and well-being. They can be tools to think with, to engage, to communicate and to help navigate in a sea of complexity. We believe models such as eDPSEEA can help frame many of the issues which have become the challenges of the new public health era and can provide the essential platforms necessary for progress.

Functional brain connectivity and deactivation in new onset schizophrenia: A pilot study

There has been previous evidence of aberrant functional connectivity in the so-called “default-mode” network (DMN) in patients with schizophrenia.

Objective

The purpose of this study was to test whether such aberrant connectivity, if existent, can be modulated by a task involving the challenge of attention, working memory and executive functioning.

Methods

A functional magnetic resonance imaging (fMRI) experiment alternating between periods of “rest” and periods of visual stimulation with successive series of pictures extracted from the Wechsler Adult Intelligence Scale-III was carried out in seven patients with new onset schizophrenia according to the DSM-IV criteria and in six healthy control subjects matched for sex, age, and education. The DMN was extracted by using independent component analysis (ICA). The degree of deactivation during periods of stimulation was tested by means of a correlation analysis. To determine the existence of differences in deactivation between patients and controls, we used a non-parametric statistical test.

Results

An overall increased activation of the DMN in patients with schizophrenia relative to control subjects seems to occur. There was also an almost significant difference in the degree of deactivation between the two groups (controls>patients, p = 0.05).

Conclusions

Aberrant connectivity of the DMN is indeed a consistent feature in schizophrenia. An altered deactivation of the DMN during a highly demanding task in patients with schizophrenia confirms previous results suggesting an abnormal behaviour of networks in the transition from “rest” to goal-directed activity.

Effects of land-use changes on landslides in a landslide-prone area (Ardesen, Rize, NE Turkey)

Various natural hazards such as landslides, avalanches, floods and debris flows can result in enormous property damages and human casualties in Eastern Black Sea region of Turkey. Mountainous topographic character and high frequency of heavy rain are the main factors for landslide occurrence in Ardesen, Rize. For this reason, the main target of the present study is to evaluate the landslide hazards using a sequence of historical aerial photographs in Ardesen (Rize), Turkey, by Photogrammetry and Geographical Information System (GIS). Landslide locations in the study area were identified by interpretation of aerial photographs dated in 1973 and 2002, and by field surveys. In the study, the selected factors conditioning landslides are lithology, slope gradient, slope aspect, vegetation cover, land class, climate, rainfall and proximity to roads. These factors were considered as effective on the occurrence of landslides. The areas under landslide threat were analyzed and mapped considering the landslide conditioning factors. Some of the conditioning factors were investigated and estimated by employing visual interpretation of aerial photos and topographic data. The results showed that the slope, lithology, terrain roughness, proximity to roads, and the cover type played important roles on landslide occurrence. The results also showed that degree of landslides was affected by the number of houses constructed in the region. As a consequence, the method employed in the study provides important benefits for landslide hazard mitigation efforts, because a combination of both photogrammetric techniques and GIS is presented.

Oncology patients' experience at the interface between hospital and community care: a mixed method investigation

Introduction

Oncology patients often experience breakdowns in care when transitioning between care settings.

Aims and objectives

To examine the experience of oncology patients at the transition between hospital and community care and identify factors which affect fragmentation.

Methods

We used a complementary mixed method approach. Qualitative phase: semi-structured interviews and focus groups were conducted with patients and their caregivers, nurses, social workers, physicians and medical administrators. Quantitative phase: a survey was administered to 400 oncology patients of a large tertiary medical center in Northern Israel. Patients who were discharged from the hospital completed a validated questionnaire on their transition from the hospital to the community and on their perceptions of the quality of their primary care. The surveys were administered in Hebrew, Arabic, and Russian.

Results

From the preliminary analysis of the qualitative data four broad themes emerged: (1) responsibility for care, (2) administrative and bureaucratic burden, (3) informal routes of communication, and (4) cultural barriers. The regression analyses examined the effect of patient characteristics (gender, age, education, income, health status, and language group) and showed that patients' language accounted for most of the variance in quality scores. Russian speaking patients reported poorer quality of care and Arabic speaking patients reported better quality of care, than Hebrew speakers, in all primary care domains. Both Arabic and Russian speakers scored significantly higher on the Care Transition Measure than Hebrew speakers.

Conclusions

The differences between sub-groups found here suggest that avoidable variations in care exist. To enable a more streamlined process, cultural issues need to be addressed at the interface between care settings. Further research should examine the causes for such differences.

Challenges in quantifying biosphere-atmosphere exchange of nitrogen species

Recent research in nitrogen exchange with the atmosphere has separated research communities according to N form. The integrated perspective needed to quantify the net effect of N on greenhouse-gas balance is being addressed by the NitroEurope Integrated Project (NEU). Recent advances have depended on improved methodologies, while ongoing challenges include gas-aerosol interactions, organic nitrogen and N(2) fluxes. The NEU strategy applies a 3-tier Flux Network together with a Manipulation Network of global-change experiments, linked by common protocols to facilitate model application. Substantial progress has been made in modelling N fluxes, especially for N(2)O, NO and bi-directional NH(3) exchange. Landscape analysis represents an emerging challenge to address the spatial interactions between farms, fields, ecosystems, catchments and air dispersion/deposition. European up-scaling of N fluxes is highly uncertain and a key priority is for better data on agricultural practices. Finally, attention is needed to develop N flux verification procedures to assess compliance with international protocols.

Degradation of keratinous materials by the plant pathogenic fungus Myrothecium verrucaria

In this paper it is described for the first time the capability of Myrothecium verrucaria to grow in submerged and solid state cultures using poultry feathers as the only substrate. The fungus produced a protease with an unusual keratinolytic activity among plant pathogenic fungi. Its crude protease hydrolyzed keratinous substrates at pH 9.0 and 40 degrees C in the following order: poultry feather keratin > sheep wool keratin > human nail keratin > human hair keratin. Protease activity was highly sensitive to phenylmethyl sulphonyl fluoride (PMSF) indicating that the enzyme belonged to the serine protease family.

An electronic pressure-meter nociception paw test for mice

The aim of the present investigation was to describe and validate an electronic mechanical test for quantification of the intensity of inflammatory nociception in mice. The electronic pressure-meter test consists of inducing the animal hindpaw flexion reflex by poking the plantar region with a polypropylene pipette tip adapted to a hand-held force transducer. This method was compared to the classical von Frey filaments test in which pressure intensity is automatically recorded after the nociceptive hindpaw flexion reflex. The electronic pressure-meter and the von Frey filaments were used to detect time versus treatment interactions of carrageenin-induced hypernociception. In two separate experiments, the electronic pressure-meter was more sensitive than the von Frey filaments for the detection of the increase in nociception (hypernociception) induced by small doses of carrageenin (30 microg). The electronic pressure-meter detected the antinociceptive effect of non-steroidal drugs in a dose-dependent manner. Indomethacin administered intraperitoneally (1.8-15 mg/kg) or intraplantarly (30-300 microg/paw) prevented the hypersensitive effect of carrageenin (100 microg/paw). The electronic pressure-meter also detected the hypernociceptive effect of prostaglandin E2 (PGE2; 10-100 ng) in a dose-dependent manner. The hypernociceptive effect of PGE2 (100 ng) was blocked by dipyrone (160 and 320 microg/paw) but not by intraplantar administration of indomethacin (300 microg/paw). The present results validate the use of the electronic pressure-meter as more sensitive than the von Frey filaments in mice. Furthermore, it is an objective and quantitative nociceptive test for the evaluation of the peripheral antinociceptive effect of anti-inflammatory analgesic drugs, which inhibit prostaglandin synthesis (indomethacin) or directly block the ongoing hypernociception (dipyrone).

The pattern and timing of breathing during incremental exercise: a normative study

Clinical evaluation of the pattern and timing of breathing during submaximal exercise can be valuable for the identification of the mechanical ventilatory consequences of different disease processes and for assessing the efficacy of certain interventions. Sedentary individuals (60 male/60 female, aged 20-80 yrs) were randomly selected from >8,000 subjects and submitted to ramp incremental cycle ergometry. Tidal volume (VT)/resting inspiratory capacity, respiratory frequency, total respiratory time (Ttot), inspiratory time (TI), expiratory time (TE), duty cycle (TI/Ttot) and mean inspiratory flow (VT/TI) were analysed at selected submaximal ventilatory intensities. Senescence and female sex were associated with a more tachypnoeic breathing pattern during isoventilation. The decline in Ttot was proportional to the TI and TE reductions, i.e. TI/Ttot was remarkably constant across age strata, independent of sex. The pattern, but not timing, of breathing was also influenced by weight and height; a set of demographically and anthropometrically based prediction equations are therefore presented. These data provide a frame of reference for assessing the normality of some clinically useful indices of the pattern and timing of breathing during incremental cycle ergometry in sedentary males and females aged 20-80 yrs.

The interaction of the Bcr-Abl tyrosine kinase with the Src kinase Hck is mediated by multiple binding domains

Bcr-Abl is found in more than 95% of cases with CML. The mechanism of Bcr-Abl-induced transformation is not fully understood. Bcr-Abl is a constitutively active tyrosine kinase with transforming capacity for hematopoietic cells. We demonstrated recently that the Src kinase Hck interacts directly with Bcr-Abl by a kinase-independent mechanism. Moreover, the inhibition of the Hck kinase seems to block some of the transforming effects of Bcr-Abl. To identify the binding domains mediating this interaction of Hck with Bcr-Abl, we co-expressed different plasmid and baculovirus vectors containing mutants or single domains of Bcr-Abl and/or Hck in COS7 and Sf9 cells. At least four independent binding regions for Hck were identified in Bcr-Abl, one in Bcr, one in the region comprising the SH3 and SH2 domain of Abl, one in the SH1 domain of Abl, and one in the C-terminal domain of Abl. In the Hck kinase, deletion of the SH2 and/or the SH3 region abolished binding to Bcr-Abl. In contrast, deletion of the Hck SH1 domain enhanced binding of Hck to Abl and Bcr-Abl. In conclusion, the results indicate that the interaction of Bcr-Abl with Hck is mediated by a novel, complex mechanism that involves multiple domains of Bcr-Abl and the SH2 and SH3 domains of Hck.

Derivative spectrophotometry as a tool for the determination of drug partition coefficients in water/dimyristoyl-L-alpha-phosphatidylglycerol (DMPG) liposomes

The partition coefficients (K(p)) between lipid bilayers of dimyristoyl-L-alpha-phosphatidylglycerol (DMPG) unilamellar liposomes and water were determined using derivative spectrophotometry for chlordiazepoxide (benzodiazepine), isoniazid and rifampicin (tuberculostatic drugs) and dibucaine (local anaesthetic). A comparison of the K(p) values in water/DMPG with those in water/DMPC (dimyristoyl-L-alpha-phosphatidylcholine) revealed that for chlordiazepoxide and isoniazid, neutral drugs at physiological pH, the partition coefficients are similar in anionic (DMPG) and zwitterionic (DMPC) liposomes. However, for ionised drugs at physiological pH, the electrostatic interactions are different with DMPG and DMPC, with the cationic dibucaine having a stronger interaction with DMPG, and the anionic rifampicin having a much larger K(p) in zwitterionic DMPC. These results show that liposomes are a better model membrane than an isotropic two-phase solvent system, such as water-octanol, to predict drug-membrane partition coefficients, as they mimic better the hydrophobic part and the outer polar charged surface of the phospholipids of natural membranes.

Determining teaching objectives for the family medicine clerkship in medical school--an Israeli national Delphi survey

BACKGROUND

Most of the published documents proposing teaching objectives for undergraduate clerkships were prepared by expert bodies. Seldom have the clinical teachers, who are critical to the learning process and to the implementation of the teaching objectives, been the actual proponents of its core content.

OBJECTIVE

To develop a national-scale proposal of teaching objectives for the family medicine clerkship in medical school, using a consensus method and the actual, community-based teachers as the expert body.

METHODS

The Delphi method was chosen for that purpose. In the first round all 189 family medicine teachers in Israeli medical schools were asked to propose five teaching objectives. In the second round the objectives, which were generated in the first round, were characterized by key words and were sent to the participants as a second round for ranking according to their importance.

RESULTS

A total of 116 family medicine teachers (61.38%) responded in the first round and 91 of the 116 (78.5%) in the second round. They formulated 51 teaching objectives listed in order of importance, covering a wide array of themes and including knowledge, attitude and skills objectives. The most important objectives were common problems in primary care, recognition of the biopsychosocial model, and understanding the importance of the doctor-patient relationship. The structure of the list provides a unique insight into the relative importance of each objective in the context of the whole core content of the clerkship.

CONCLUSIONS

Constructing a proposal for teaching objectives is feasible using the Delphi method and the field instructors as the selecting body. The process and its results can provide faculty with relevant and important suggestions on the content and structure of the family medicine clerkship.

Trends in medical specialty choice among Israeli medical graduates, 1980-1995

BACKGROUND

Which medical specialties do Israeli medical graduates choose? Answers to this question can serve as an essential means of evaluating both Israeli medical education and the healthcare system.

OBJECTIVES

To determine the distribution of medical specialty choice, its change over time and the possible influence of the medical school on the choice; to study the graduates' gender, gender variability in specialty choice and time trends in both; and to assess the choice of family medicine as a career among the graduates as a group, by medical school, gender, and time trends.

METHODS

The study population comprised all graduates of the four medical schools in Israel during 16 years: 1980-1995 inclusive. Data were obtained from the four medical schools, the Israel Medical Association's Scientific Council, and the Ministry of Health. Data allowed for correct identification of two-thirds of the graduates.

RESULTS

A total of 4,578 physicians graduated during this period. There was a significant growth trend in the proportion of women graduates from 22.6% in 1980 (lowest: 20.0% in 1981) to 35.3 in 1995 (highest: 41.5% in 1991). Overall, 3,063 physicians (66.8%) started residency and 1,714 (37.4%) became specialists. The four most popular residencies were internal medicine, pediatrics, obstetrics and gynecology, and family medicine. Ten percent of Israeli graduates choose family medicine.

CONCLUSIONS

The overall class size in Israel was stable at a time of considerable population change. Women's place in Israeli medicine is undergoing significant change. Family medicine is one of the four most popular residencies. A monitoring system for MSC in Israel is imperative.

Doctor-patient discussions of alternative medicine for back pain

OBJECTIVE

To document the frequency of conversations about alternative medicine during primary care consultations for back pain in diverse settings.

DESIGN

"Exit interview" type patient survey.

SETTINGS

General practices in Seattle, Washington; rural Israel; and Birmingham, England.

PATIENTS

A convenience sample of 218 adults completing a doctor visit for back pain.

MAIN OUTCOME MEASURES

Frequencies of doctor-patient discussions of alternative medicine.

RESULTS

Alternative medicine was discussed in a minority of visits (US site 40%, Israel site 37%, UK site 14%, p < 0.05). At each site, patients initiated at least half of the discussions. Users were five to six times more likely to discuss alternative medicine with their doctor than non-users (p < 0.05 for comparison at each site). The percentage of patients who used alternative medicine but left the consultation without discussing it was similar at all sites (US site 17%, Israel site 23%, UK site 15%).

CONCLUSIONS

Discussions of alternative medicine occurred in a minority of consultations for back pain although the rate varied considerably by site. Discussions were initiated primarily by patients who use it.

Assessment of a rapid HIV test strategy during labor: a pilot study from Rio de Janeiro, Brazil

OBJECTIVES

To use two rapid human immunodeficiency virus (HIV) tests at labor, measure test acceptance and performance, and measure HIV prevalence in these women.

METHODS

Between February and October 2000, two rapid tests (Determine; Abbott, Chicago, IL, U.S.A. and Double Check; Orgenics, Yavne, Israel) were used in three public maternities in Rio de Janeiro, Brazil. Enzyme-linked immunosorbent assay (ELISA) and Western blot (WB) analysis confirmed positive and discordant results.

RESULTS

Of the 858 patients who were enrolled, the mean gestational age was 36 weeks (median = 39, mode = 40) and 17 (2%) refused testing. Of the 841 patients tested, 13 were positive by both tests, which represents a 1.5% prevalence (95% confidence interval: 0.7%-2.3%); all were confirmed by ELISA and WB analysis. Seven samples gave discordant results by the rapid tests; of these, six were ELISA-negative/WB-negative and one was ELISA-negative/WB-indeterminate. The positive predictive value for samples that were positive by both rapid tests simultaneously was 100%.

CONCLUSIONS

Two rapid HIV tests used at labor were well accepted (98%). When the combined results of the two rapid tests (but not a single rapid test) were analyzed, this strategy was as efficient as the standard ELISA and WB HIV strategy for correctly classifying individuals.