Assessing the trophic ecology and migration on the exposure of cape petrels and Wilson's storm petrels from Antarctica to perfluoroalkylated substances, trace and major elements

Chemical pollution is a global concern as contaminants are transported and reach even the remote regions of Antarctica. Seabirds serve as important sentinels of pollution due to their high trophic position and wide distribution. This study examines the influence of migration and trophic ecology on the exposure of two Antarctic seabirds, Wilson's storm petrel (Oceanites oceanicus - Ooc), and Cape petrel (Daption capense - Dca), to chemical elements and perfluoroalkyl substances (PFAS). Our methodology involved assessing the concentration of these pollutants in feather samples obtained from carcasses, offering a practical means for monitoring contamination. Trace and major element concentrations were comparable in both species, suggesting that migratory patterns have a minimal impact on exposure levels. However, Ooc had higher concentration of PFAS compared to Dca (mean, ng g-1dry weight, PFOA: Ooc:0.710, Dca:0.170; PFTrDA: Ooc:0.550, Dca:0.360, and PFTeDA: Ooc:1.01, Dca:0.190), indicating that migration to the more polluted Northern Hemisphere significantly affects PFAS exposure. Furthermore, while no strong associations were found between either trace elements or PFAS and the three stable isotopes (δ13C, δ15N, and δ34S), a negative association was observed between PFUnDA and δ15N, hinting at potential biodilution. The research concludes that the migratory patterns of these seabird species affect their PFAS exposure, underscoring the critical need for further exploration and understanding of these relationships to better inform conservation strategies.

Impact of annual TB screening on stone quarry workers in high-incidence Portuguese municipalities

SETTING

The Portuguese municipalities of Penafiel and Marco de Canaveses are high TB incidence areas, where stone quarry workers represent a vulnerable population.

OBJECTIVE

To assess the annual rate of TB infection (ARI) in stone quarry workers and to compare it with the TB notification rate in the general community.

DESIGN

An annual TB infection screening strategy using interferon-gamma release assay (IGRA) was implemented in 2018 for workers from high-risk stone quarries. A prospective cohort was enrolled and workers screened in periods of 2 years were included. IGRA-positive workers were referred for preventive treatment. ARI was calculated as the proportion of workers with IGRA conversion.

RESULTS

Of the 232 IGRA-negative workers in 2018, 20 tested positive in 2019 (8.6% ARI). Of 171 IGRA-negative workers in 2019, eight tested positive in 2021 (4.7% in 2 years). Two of the 150 IGRA-negative workers in 2021 tested positive in 2022 (1.3% ARI). ARI decreased by 84.9% between 2019 and 2022. In the two municipalities, the TB notification rate declined 23.9% between 2018 and 2021.

CONCLUSION

A more pronounced reduction in ARI was observed among stone quarry workers regularly screened for TB infection compared to the notification rate among the general population in high-incidence municipalities. A screening strategy for high-risk populations, together with enforced community measures, could foster risk reduction in the community..

Obstructive Sleep Apnea: a risk for uncontrolled and more severe asthma in adults that we should keep an eye on

Summary

Background. Asthma control can be influenced by several factors, including obstructive sleep apnea (OSA). The literature reports variable prevalence and magnitude of OSA impact on asthma outcomes. The aim of our study is to analyze the frequency of high-risk for OSA in asthma patients and its impact on disease severity and control. Methods. We conducted a cross-sectional study at an Allergy Department with adult asthma patients recruited while undergoing routine lung function tests. Data on sex, age, body mass index, allergen sensitization, smoking habits, risk of OSA (using the Berlin questionnaire), rhinitis control (through CARAT), asthma severity (based on GINA 2023), asthma control (using the ACT), adherence to asthma treatment (through Treatment Adherence Measure) and pulmonary function test results were collected. Results. We included 216 patients, predominantly women (70.4%), with a median (P25-P75) age of 29.0 (21.0-45.0) years, of whom 28.2% were on GINA treatment levels 4-5. In 75.5% of cases asthma was controlled. High-risk for OSA was identified in 21.8% of patients. Asthma patients with high-risk for OSA were more likely to have uncontrolled [(47.8%; n = 22) vs (15.8%; n = 26); p less than 0.001] and more severe disease [(44.7%; n = 21) vs (23.7%; n = 40), p = 0.006]. In multivariable analysis, high-risk for OSA (OR 2.81 [95%CI 1.1.28-6.17], p = 0.010), sex (women) (OR 5.21 [95% CI 1.70-15.96], p = 0.004), uncontrolled rhinitis (OR 3.65 [95%CI 1.38-9.64], p = 0.009) and GINA asthma treatment steps 4-5 (OR 2.46 [95%CI 1.15-5.26], p = 0.020) were associated with uncontrolled asthma. Conclusions. It is crucial to actively investigate OSA, especially in patients with uncontrolled and more severe forms of asthma.

Mercury exposure in Antarctic seabirds: Assessing the influence of trophic position and migration patterns

Although naturally present in the environment, mercury (Hg) input is significantly amplified by anthropogenic activities on a global scale, leading to a growing concern about the recent increase in Hg levels observed in Antarctica. This study investigated total mercury (THg) concentrations in feathers and eggs of resident and migratory Antarctic seabirds. Stable isotope data (δ15N, δ13C, and δ34S) were employed to ascertain the key factors influencing the exposure of these species to Hg. We gathered feathers and eggs from three resident species - Adélie, Gentoo, and Chinstrap penguins, as well as five migratory species - Snowy Sheathbill, Antarctic Tern, Southern Giant Petrel, Kelp Gull, and South Polar Skua. These samples were collected from Admiralty Bay, King George Island, in the Antarctica Peninsula. For all species, THg concentrations were higher in feathers (mean ± SD: 2267 ± 2480 ng g-1 dw) than in eggs (906 ± 1461 ng g-1 dw). Species occupying higher trophic positions, such as the Southern Giant Petrel (5667 ± 1500 ng g-1 dw) and South Polar Skua (4216 ± 1101 ng. g-1 dw), exhibited higher THg levels in their feathers than those at lower positions, like Antarctic Tern (1254 ± 400 ng g-1 dw) and Chinstrap Penguin (910 ± 364 ng g-1 dw). The δ15N values, which serve as a proxy for the trophic position, significantly correlated with THg concentrations. These findings reveal that trophic position influences THg concentrations in Antarctic seabirds. Migration did not appear to significantly affect the exposure of seabirds to THg, contrary to initial expectations. This research highlights the importance of evaluating the impacts of THg contamination on the Antarctic ecosystem by considering a variety of species. This multi-species approach offers critical insights into the factors that may potentially influence the exposure of these species to contaminants.

Maternal care experience and postpartum depressive symptoms among migrant and native in Portugal

Background

Migration is a risk factor for both, poor maternal experience with healthcare services (MEHCS) and postpartum depressive symptoms (PPDS), a matter of concern due to their adverse consequences. We aimed to assess the association between MEHCS and PPDS taking into account the migration status.

Methods

This is part of a population-based study (baMBINO project), enrolling native (PT; n = 1568), permanent migrant (PM; n = 676) and temporary migrant (TM; n = 757) women recruited at delivery (2017-2019) in 32 Portuguese public hospitals. MEHCS was assessed based on 39 items of the Migrant Friendly Maternal Care Questionnaire asking about how women have experienced maternal care during pregnancy, during delivery and after birth. Items were grouped into 9 components each one assessing a different issue of MEHCS. For each component women were classified as having “good” or “less than good” experience. PPDS were assessed using the Edinburgh Postnatal Depression Scale (cut-off≥12). Multivariate logistic regression model was fitted to estimate the association between MEHCS and PPDS. Adjusted odds ratio (aOR) and respective 95% confidence interval were obtained.

Results

PPDS were reported by 3.8%, 5.8% and 8.2% of PT, PM and TM women, respectively (p < 0.001). After adjustment, 4 out 9 components of MEHCS appeared related with PPDS, such that women reporting less than good experience with “understanding information” (aOR=1.72 95%CI:1.14-2.60), “decisions according to maternal wishes” (aOR=1.56 95% CI:1.04-2.34), “time waiting for healthcare” (aOR=1.50 95%CI:1.04-2.18) and “healthcare provider's attitudes during pregnancy” (aOR=1.58 95%CI:1.01-2.47) showed higher odds of PPDS than women reporting good experience.

Conclusions

Further than the migration status, poor experience with some issues of maternal care seems play a role in the risk of PPDS

Key messages

P-505 Mapping acceptance and commitment therapy (ACT) outcomes in the context of infertility: A systematic review

Study question

How ACT variables are associated or may impact mental health outcomes (i.e., anxiety, stress, and depression symptoms) in patients with an infertility diagnosis?

Summary answer

ACT variables seem to be associated with better mental health outcomes in patients with an infertility diagnosis.

What is known already

Evidence indicates that people with infertility face psychosocial challenges, with a significant number of studies finding that mental health seems to be negatively affected. ACT is part of the family of behavioral and cognitive therapies and was already established as having a beneficial effect on psychological issues in other health conditions. Since infertility is a relevant stressor, we expected that ACT had also a protective role on mental health. To date, no study tried to summarize this evidence, which might help to develop the intervention with ACT components for this population.

Study design, size, duration

A systematic review of the literature was conducted to identify studies assessing Infertility and ACT. A literature search was conducted from inception to October 2021 in the following electronic databases: Web of Science, Pubmed, and B-On. The PRISMA guidelines were followed.

Participants/materials, setting, methods

A search was conducted using combinations of keywords and MeSH (“infertility” AND “Acceptance and Commitment Therapy” AND “depression”; “anxiety”; “stress”). No limitation regarding the type of publication, date, or language was created during the searches. Empirical and quantitative studies were considered if they assessed mental health variables and ACT hexagon model components in patients with infertility.

Main results and the role of chance

Out of 137 studies initially identified, six of them met eligibility criteria and were included in the review. The studies were carried out between 2012 and 2020 and originated from two countries: four from Portugal and two from Iran. The samples were composed by women (three) and couples (three). The results revealed that couples dealing with infertility present higher psychological inflexibility and experiential avoidance scores, and lower scores of acceptance when compared with fertile couples and couples who pursued adoption. Psychological inflexibility seems to be positively correlated with depressive, anxiety, and stress symptoms. Gender differences were also found, i.e., women tend to show higher scores of depression symptoms, psychological inflexibility, and experiential avoidance than men. Women dealing with infertility have the tendency to avoid thoughts, emotions, and situations somehow associated with pregnancy and parenthood as a way of trying to escape from infertility’s painful experience. In general, studies suggest that ACT may be an adequate approach for patients dealing with infertility.

Limitations, reasons for caution

The number of studies was small and they were predominantly from Portugal, increasing the likelihood of a risk of bias of the findings. Cultural variables must be considered and conclusions need to be interpreted with caution.

Wider implications of the findings

Since ACT variables seem to be associated with better mental health outcomes, these results indicated that couples with infertility would benefit from intervention addressing ACT components. Future studies should explore the effectiveness of these interventions in this population.

Trial registration number

not applicable

P-803 DNA-FISH analysis in testicular tissue cells of prepuberal patients with Klinefelter Syndrome

Study question

Can we accurately assess sex-chromosomes number in testicular cells (germ and somatic) of Klinefelter Syndrome (KS) prepuberal patients by DNA-FISH in paraffin embedded sections?

Summary answer

We have evaluated the sex-chromosomes content of testicular cells in KS prepuberal patients and the presence of XY lines evidenced a gonadal mosaicism status.

What is known already

Prepuberal boys with Klinefelter Syndrome usually have fertility problems in adulthood, mainly azoospermia. Due to the symptoms cause by the disease, Spermatogonial Stem Cells (SSCs) are less abundant and spermatogenesis does not occur. These patients do not have any alternative to restore the fertility in the future. When a boy has both XY and XXY cell lines, this patient is mosaic (46,XY/47,XXY). Meaning some cells could undergo spermatogenesis and generate gametes with normal sex-chromosomes number. The aim of this work is to test if KS patients diagnosed as pure can have testicular cell lines with XY chromosome number (mosaic).

Study design, size, duration

We obtained samples from human prepuberal patients diagnosed with pure Klinefelter Syndrome (47,XXY) for the last 5 years. Testicular biopsy fragments are fixed for histological studies and other fragments are cryopreserved. Some fragments are used for immunofluorescence and subsequently processed by DNA-FISH to determine the sex-chromosomes content of testicular cells.

Participants/materials, setting, methods

In this study, we used 10 prepuberal patients with KS and 5 prepuberal patients with other fertility problems with normal chromosome set as controls. We performed immunofluorescence to determine expression of germ cells (VASA) and SSCs (MAGEA4) markers and somatic cells markers such as Leydig cells (StAR) and Sertoli cells (SOX9). Afterwards, we perform DNA-FISH, with probes specific for chromosomes X and Y and chromosome 18 as a control.

Main results and the role of chance

The methodology used allows cytogenetic characterization of testicular tissue in paraffin embedded sections. Testicular mosaicism has been observed in all patients diagnosed as pure KS. We have observed a degree of mosaicism of 66-80% in SSCs, of 20-50% in Sertoli cells and of 30-50% in Leydig cells.

We pursued a protocol with a good FISH efficiency that allows colocalization of previous immunocharacterized testicular cells.

Limitations, reasons for caution

The DNA-FISH technique is made just in a single paraffin section of each KS patient testicular sample. Due to the limited and difficulty to obtain KS testicular tissue, we use a limited number of samples.

Wider implications of the findings

We succeed to demonstrate the mosaicism of testicular cells in prepuberal patients that are diagnosed with KS. Thus, the better understanding of the SSCs with normal chromosome set (XY) could be useful for future in vitro expansion and stem cell therapies.

Trial registration number

not applicable

Pharmacological Targeting of Senescence with ABT-263 in Experimental Heart Failure with Preserved Ejection Fraction

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Fundação Ciência e Tecnlogia

HFpEF is the most common form of heart disease in the elderly and is associated with high morbidity and mortality. Our understanding of HFpEF pathophysiology is limited and development of efficient therapies that alter the clinical course of the disease has proved greatly challenging. Although aging is a risk factor of HFpEF1, the involvement of aging hallmarks such as cell senescent and immunosenescence is unclear. Recently, a link between endothelial senescence and HFpEF development was demonstrated in mice with accelerated aging [1], endorsing anti-aging pharmacologic as potential new therapeutic alternatives for HFpEF. In fact, the senolytic (drugs that selectively promote apoptosis of senescent cells) ABT-263 has already proven efficacy in the context of cardiovascular diseases. Further studies are needed to clarify the relevance of aging and of anti-aging therapies in the context of HFpEF.

Using ZSF1 obese rats (ZSF1-Ob) as model of HFpEF we showed from 18 weeks signs of immunosenescence compared to ZSF1-Ln, namely an increased frequency of circulating myeloid cells and decreased frequency of T and B cells. Concomitantly, expression of pro-inflammatory factors (IL-6, IL-1, TGF-β, TNF-α) was upregulated in peripheral blood mononuclear cells (PBMCs) of ZSF1-Ob which also displayed characteristic features of cell senescence (p21 expression, lysosomal endogenous Beta-galactosidase (SA-B-Gal) senescence-associated secretory phenotype (SASP) and up-regulation of BCL-XL. Importantly, no signs of cellular senescence (SA-B-gal, pH2AX and senescence associated pathways) were found in the main hematopoietic organs (spleen and bone marrow). Alongside, these systemic alterations, an upsurge of cellular senescence was observed in myocardium of ZSF1-Ob rats, particularly in endothelial and hematopoietic cells. Serum of ZSF1-Ob rat was able to induce activation and cellular senescence of cardiac microvascular endothelial cells, indicating that systemic circulating factors may be the upstream mechanism of cellular senescence and dysfunction in HFpEF. Analysis of HFpEF patients and a control cohort adjusted to main co-morbidities further demonstrated accumulation of senescent monocytes in HFpEF patients. In these patients, the senescence marker SA-B-Gal correlated with plasmatic brain natriuretic peptide (BNP) levels and pulmonary artery systolic pressure. Targeting aging hallmarks through the treatment of ZSF1-Ob rat with ABT-263 resulted in a reduction in circulating senescent cells, decreased systemic and local inflammation, re-established immune proportions, restore the levels of circulating BNP and attenuated myocardial remodeling, particularly endothelial dysfunction and fibrosis.

Collectively these findings support that premature cellular senescence contributes to the establishment of a deleterious pro-inflammatory environment in HFpEF and that senolytic agents hold promise for the treatment of this syndrome.

Proteomics of sea bass skin-scales exposed to the emerging pollutant fluoxetine compared to estradiol

Teleost fish skin-scales are essential for protection and homeostasis and the largest tissue in direct contact with the environment, but their potential as early indicators of pollutant exposure are hampered by limited knowledge about this model. This study evaluated multi-level impacts of in vivo exposure of European sea bass to fluoxetine (FLX, a selective serotonin-reuptake inhibitor and an emerging pollutant) and 17β-estradiol (E2, a natural hormone and representative of diverse estrogenic endocrine-disrupting pollutants). Exposed fish had significantly increased circulating levels of FLX and its active metabolite nor-FLX that, in contrast to E2, did not have estrogenic effects on most fish plasma and scale indicators. Quantitative proteomics using SWATH-MS identified 985 proteins in the scale total proteome. 213 proteins were significantly modified 5 days after exposure to E2 or FLX and 31 were common to both treatments and responded in the same way. Common biological processes significantly affected by both treatments were protein turnover and cytoskeleton reorganization. E2 specifically up-regulated proteins related to protein production and degradation and down-regulated the cytoskeleton/extracellular matrix and innate immune proteins. FLX caused both up- and down-regulation of protein synthesis and energy metabolism. Multiple estrogen and serotonin receptor and transporter transcripts were altered in sea bass scales after E2 and/or FLX exposure, revealing complex disruptive effects in estrogen/serotonin responsiveness, which may account for the partially overlapping effects of E2 and FLX on the proteome. A large number (103) of FLX-specifically regulated proteins indicated numerous actions independent of estrogen signalling. This study provides the first quantitative proteome of the fish skin-scale barrier, elucidates routes of action and biochemical and molecular signatures of E2 or FLX-exposure and identifies potential physiological consequences and candidate biomarkers of pollutant exposure, for monitoring and risk assessment.

Effects of stress exposure in captivity on physiology and infection in avian hosts: no evidence of increased Borrelia burgdorferi s.l. infectivity to vector ticks

Exposure to environmental stressors, an increasingly recurring event in natural communities due to anthropogenic-induced environmental change, profoundly impacts disease emergence and spread. One mechanism through which this occurs is through stress-induced immunosuppression increasing disease susceptibility, prevalence, intensity and reactivation in hosts. We experimentally evaluated how exposure to stressors affected both the physiology of avian hosts and the prevalence of the zoonotic bacteria Borrelia burgdorferi sensu lato (s.l.), in two model species-the blackbird Turdus merula and the robin Erithacus rubecula captured in the wild, using xenodiagnoses and analysis of skin biopsies and blood. Although exposure to stressors in captivity induced physiological stress in birds (increased the number of circulating heterophils), there was no evidence of increased infectivity to xenodiagnostic ticks. However, Borrelia detection in the blood for both experimental groups of blackbirds was higher by the end of the captivity period. The infectivity and efficiency of transmission were higher for blackbirds than robins. When comparing different methodologies to determine infection status, xenodiagnosis was a more sensitive method than skin biopsies and blood samples, which could be attributed to mild levels of infection in these avian hosts and/or dynamics and timing of Borrelia infection relapses and redistribution in tissues.

Impact of COVID-19 disease on platelet reactivity and association with inflammatory parameters

Background

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the pathogen responsible for the coronavirus disease 2019 (COVID-19) pandemic. Aside from the pulmonary manifestations, COVID-19 is associated with increased risk of venous and arterial thrombotic complications. The actual impact of SARS-CoV-2 infection on platelet reactivity and whether this is mediated by a hyperinflammatory status has not been fully elucidated to date.

Objective

To evaluate platelet reactivity in COVID-19 patients compared to healthy subjects and to assess the association between platelet reactivity and levels of inflammatory biomarkers among COVID-19 patients.

Methods

This prospective observational investigation included COVID-19 patients admitted into a tertiary care hospital and adult healthy volunteers, all of them not receiving any antiplatelet therapy. Subjects were classified in three groups: 1) Healthy subjects (HS group); 2) COVID-19 patients in a pulmonary phase (viral pneumonia and bilateral infiltrates) but without meeting criteria for systemic hyperinflammation (C19-Pulm group); and 3) COVID-19 patients in a hyperinflammation phase (C19-Infl group) meeting at least 2 of the following criteria: CRP>100mg/l, D-dimer >1000mcg/l, LDH>400U/l, ferritin>1000ng/ml, IL-6>70ng/l. Blood samples for platelet function testing and quantification of inflammatory parkers were collected at a single visit. Platelet function was measured with multiple electrode aggregometry using ADP (MEA-ADP, primary endpoint), arachidonic acid (AA) and thrombin receptor activating peptide (TRAP) as stimuli. Unadjusted analyses are presented.

Results

A total of 60 patients were included in the present investigation (20 in each group). A significantly greater platelet reactivity, measured with MEA-ADP, was observed in both groups of COVID-patients compared to healthy subjects (HS: 634,9±53,5, C19-Pulm: 919,9±53,5 and C19-Infl: 931,6±53,5 AU*min; p for C19-Pulm vs. HS <0,001, p for C19-Infl vs. HS <0,001, p for C19-Pulm vs. C19-Infl 0,878; Figure 1). Parallel findings were found when using AA as stimulus for platelet aggregation showing greater platelet aggregation in COVID-19 patients compared to healthy subjects, but numerical differences were not statistically significant when using TRAP. Among COVID-19 patients, when stratified by IL-6 levels splitted into tertiles, greater platelet reactivity was observed in patients with higher IL-6 concentrations (mid and upper tertile together) compared to those with values in the lower tertile, as assessed with MEA-ADP (lower tertile: 829,0±75,8, mid and upper tertile: 1028,7±56,2; p=0,043); a similar trend was observed with AA and TRAP as stimuli.

Conclusion

Patients with severe COVID-19 disease have greater platelet reactivity than healthy subjects. Increased IL-6 levels might be associated with the observed heightened platelet reactivity among COVID-19 patients.

Funding Acknowledgement

Type of funding sources: None.

Ancestral genetic legacy of the extant population of Argentina as predicted by autosomal and X-chromosomal DIPs

Aiming to determine their ancestry diagnostic potential, we selected two sets of nuclear deletion/insertion polymorphisms (DIPs), including 30 located on autosomal chromosomes and 33 on the X chromosome. We analysed over 200 unrelated Argentinean individuals living in urban areas of Argentina. As in most American countries, the extant Argentinean population is the result of tricontinental genetic admixture. The peopling process within the continent was characterised by mating bias involving Native American and enslaved African females and European males. Differential results were detected between autosomal DIPs and X-DIPs. The former showed that the European component was the largest (77.8%), followed by the Native American (17.9%) and African (4.2%) components, in good agreement with the previously published results. In contrast, X-DIPs showed that the European genetic contribution was also predominant but much smaller (52.9%) and considerably larger Native American and African contributions (39.6% and 7.5%, respectively). Genetic analysis revealed continental genetic contributions whose associated phenotypic traits have been mostly lost. The observed differences between the estimated continental genetic contribution proportions based on autosomal DIPs and X-DIPs reflect the effects of autosome and X-chromosome transmission behaviour and their different recombination patterns. This work shows the ability of the tested DIP panels to infer ancestry and confirm mating bias. To the best of our knowledge, this is the first study focusing on ancestry-informative autosomal DIP and X-DIP comparisons performed in a sample representing the entire Argentinean population.

Chondrocytes respond both anabolically and catabolically to impact loading generally considered non-injurious

We aimed to determine the longitudinal effects of low-energy (generally considered non-injurious) impact loading on (1) chondrocyte proliferation, (2) chondroprogenitor cell activity, and (3) EGFR signaling. In an in vitro study, we assessed 127 full-thickness, cylindrical osteochondral plugs of bovine cartilage undergoing either single, uniaxial unconfined impact loads with energy densities in the range of 1.5-3.2mJ/mm³ or no impact (controls). We quantified cell responses at two, 24, 48, and 72 h via immunohistochemical labeling of Ki67, Sox9, and pEGFR antibodies. We compared strain, stress, and impact energy density as predictors for mechanotransductive responses from cells, and fit significant correlations using linear regressions. Our study demonstrates that low-energy mechanical impacts (1.5-3.2mJ/mm³) generally stimulate time-dependent anabolic responses in the superficial zone of articular cartilage and catabolic responses in the middle and deep zones. We also found that impact energy density is the most consistent predictor of cell responses to low-energy impact loading. These spatial and temporal changes in chondrocyte behavior result directly from low-energy mechanical impacts, revealing a new level of mechanotransductive sensitivity in chondrocytes not previously appreciated.

Generation, establishment and characterization of a pluripotent stem cell line (CVTTHi001-A) from primary fibroblasts isolated from a patient with activated PI3 kinase delta syndrome (APDS2)

APDS2 is caused by mutations in PIK3R1 gene resulting in constitutive PI3Kδ activation. PI3Kδ is predominantly expressed in leukocytes and plays critical roles in regulating immune responses. Here we first derived fibroblast primary cells from a skin biopsy of a patient carrying a heterozygous single T deletion in intron 11 of the PIK3R1 gene. We next present the derivation of an induced pluripotent stem cell (iPS) line using a non-integrative reprogramming technology. Pluripotent-related hallmarks are further shown, including: iPSCs self-renewal and expression of pluripotent and differentiation markers after in vitro differentiation towards embryonic germ layers, assessed by RT-PCR and immunofluorescence.

The heterogeneous morphology of networked collagen in distal colon and rectum of mice quantified via nonlinear microscopy

Visceral pain from the distal colon and rectum (colorectum) is a major complaint of patients with irritable bowel syndrome. Mechanotransduction of colorectal distension/stretch appears to play a critical role in visceral nociception, and further understanding requires improved knowledge of the micromechanical environments at different sub-layers of the colorectum. In this study, we conducted nonlinear imaging via second harmonic generation to quantify the thickness of each distinct through-thickness layer of the colorectum, as well as the principal orientations, corresponding dispersions in orientations, and the distributions of diameters of collagen fibers within each of these layers. From C57BL/6 mice of both sexes (8-16 weeks of age, 25-35 g), we dissected the distal 30 mm of the large bowel including the colorectum, divided these into three even segments, and harvested specimens (~8 × 8 mm²) from each segment. We stretched the specimens either by colorectal distension to 20 mmHg (reference) or 80 mmHg (deformed) or by biaxial stretch to 10 mN (reference) or 80 mN (deformed), and fixed them with 4% paraformaldehyde. We then conducted SHG imaging through the wall thickness and analyzed post-hoc using custom-built software to quantify the orientations of collagen fibers in all distinct layers. We also quantified the thickness of each layer of the colorectum, and the corresponding distributions of collagen density and diameters of fibers. We found collagen concentrated in the submucosal layer. The average diameter of collagen fibers was greatest in the submucosal layer, followed by the serosal and muscular layers. Collagen fibers aligned with muscle fibers in the two muscular layers, whereas their orientation varied greatly with location in the serosal layer. In colonic segments, thick collagen fibers in the submucosa presented two major orientations aligned approximately ±30° to the axial direction, and form a patterned network. Our results indicate the submucosa is likely the principal passive load-bearing structure of the colorectum. In addition, afferent endings in those collagen-rich regions present likely candidates of colorectal nociceptors to encode noxious distension/stretch.

Tuberculosis: where and how fast are stone quarry workers infected?

Background

In 2018 an annual tuberculosis (TB) screening program targeting stone quarry workers was implemented in two municipalities in Northern Portugal. These have been hotspots for TB (76 and 59 cases per 100 000 population per year in 2012-2016, well above the 18 cases per 100 000 population observed in Portugal in 2016), with 30% of active TB cases occurring among stone quarry workers. Screening in this setting is recommended by the World Health Organization, as exposure to silica and silicosis increase the risk of TB. Occupational health services, TB outpatient centers, the hospital, a laboratory, primary health care and public health services work closely together with employers, employees, municipal council and the community promoting meetings and continuous training.

Screening activities included a symptom questionnaire, chest X-ray and sputum exam; and, after exclusion of active TB, interferon-gamma release assay (IGRA) for latent tuberculosis infection (LTBI). Preventive treatment was offered.

Objective

Assess annual rate of TB infection

Methods

Workers without history of TB/LTBI were IGRA tested in 2018, and retested in 2019. Annual rate of infection was calculated as the proportion of workers IGRA negative in 2018 becoming positive in 2019.

Results

In 2018-2019, 274 workers were screened yearly. In 2018, 22 were diagnosed with LTBI and 26 had previous history of TB/LTBI. Out of 226 IGRA negative workers in 2018, 19 tested positive in 2019 (8.4% annual rate of infection). These individuals were not identified as close contacts of any new TB case and no cases of active TB were reported in their stone quarries. Some active TB cases were regular customers of specific bars.

Conclusions

Active transmission of TB seems to be occurring among stone quarry workers. Workers that converted from IGRA negative to positive had no co-workers with active TB in the study period, suggesting they could have been infected away from the workplace, possibly in community public places.

Key messages

Stone quarry workers in a high-risk TB sub-region were infected at an 8.4% annual rate, and could have been infected in community public places such as bars. Besides screening close contacts and at workplace, more efforts should be made identifying social contacts of active TB cases.

Interprofessional health education and its impact on integral healthcare

Background

Interprofessionality is a tool for optimizing the human resources available towards the consolidation of a resolutive healthcare. However, applying it is a challenge due to the fragmented training of health professionals.

Objective

to describe the experience of planning and executing an interprofessional health education activity.

Methods

An educational workshop was developed aiming at interprofessional health practice. A clinical case was distributed, which addressed the story of an elderly person who suffered a stroke and lived with the sequels of this episode in addition to emotional trauma from the experience. Each professional was asked to define a therapeutic proposal for the case and one of them was invited to present his proposal and complement it based on the suggestions of the other members.

Results

the workshop enabled the perception that, in isolation, no profession would be able to fully contemplate the patient's needs. Therefore, it encouraged the use of integrated action between different professionals by demonstrating that punctual and disjointed actions would not be sufficient to act effectively in the care and needs related to the individual's health.

Conclusions

the final product of this workshop resulted in a consistent activity contemplated by multiple perspectives, experiences and knowledges which would not be so successful if planned in isolation by a single professional group.

Key messages

Due to its low cost, interprofessional action responds to the new health needs of contemporary times and its implementation is of great value in combating the fragmented trend in health training. The interprofessional view is a common ground to health not only where the study took place but worldwide, consolidating itself as a valuable asset to the construction of integral healthcare.

International Nosocomial Infection Control Consortium (INICC) report, data summary of 45 countries for 2012-2017: Device-associated module

BACKGROUND

We report the results of International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2012 to December 2017 in 523 intensive care units (ICUs) in 45 countries from Latin America, Europe, Eastern Mediterranean, Southeast Asia, and Western Pacific.

METHODS

During the 6-year study period, prospective data from 532,483 ICU patients hospitalized in 242 hospitals, for an aggregate of 2,197,304 patient days, were collected through the INICC Surveillance Online System (ISOS). The Centers for Disease Control and Prevention-National Healthcare Safety Network (CDC-NHSN) definitions for device-associated health care-associated infection (DA-HAI) were applied.

RESULTS

Although device use in INICC ICUs was similar to that reported from CDC-NHSN ICUs, DA-HAI rates were higher in the INICC ICUs: in the medical-surgical ICUs, the pooled central line-associated bloodstream infection rate was higher (5.05 vs 0.8 per 1,000 central line-days); the ventilator-associated pneumonia rate was also higher (14.1 vs 0.9 per 1,000 ventilator-days,), as well as the rate of catheter-associated urinary tract infection (5.1 vs 1.7 per 1,000 catheter-days). From blood cultures samples, frequencies of resistance, such as of Pseudomonas aeruginosa to piperacillin-tazobactam (33.0% vs 18.3%), were also higher.

CONCLUSIONS

Despite a significant trend toward the reduction in INICC ICUs, DA-HAI rates are still much higher compared with CDC-NHSN's ICUs representing the developed world. It is INICC's main goal to provide basic and cost-effective resources, through the INICC Surveillance Online System to tackle the burden of DA-HAIs effectively.

Abstract P6-08-36: Uptake of preventive surgeries in a prospective cohort of BRCA1/2 healthy women

PURPOSE

Previous studies referred to uptake of preventive surgeries (PS) in BRCA1/2 healthy carriers in ages older than recommended (35yrs). Since our population has a higher prevalence of BRCA2 mutations (usually associated with an older age at Breast Cancer diagnosis) we proposed to study ages and type of preventive surgeries uptaken by BRCA1/2 women included in prospective follow up.

PATIENTS AND METHODS

Review of all healthy (without a previous cancer diagnosis) BRCA1/2 carriers included in our program from January 2000 to June 2019. Follow-up started after genetic testing. Men were excluded from this analysis.

RESULTS

A total of 5504 cases (4021 index, 1483 relatives) consented for BRCA1/2 testing. We identified 238 healthy BRCA1/2 carriers (BRCA2:158 (66.4%) vs BRCA1 80 (33.6%). Median age at genetic diagnosis was 38.9 yrs (16-78). With a median follow up of 4yrs, bilateral adnexectomy (BA) was the most frequent PS observed (45 BRCA2 and 28 BRCA1 cases) with 15/45 % and 6/28% undergoing BA and bilateral mastectomy (BM) simultaneously. Bilateral mastectomy was uptaken by 14% BRCA2 women and 10% BRCA1 women. Median ages for PS were: BRCA2-AB: 47,4 (28-71), BRCA1-AB: 46.7 (37-59); BRCA2-BM: 36.6 (31-52) and BRCA1-BM:42.5 (30-55). Isolated BM was observed in 7 BRCA2 cases and 2 BRCA1 cases. Most of women submitted to BA, also underwent total hysterectomy (HT): 65% for BRCA2 and 61% BRCA1. Most cases (88% non-adherent) adhere to radiological surveillance, 111/238 with annual breast S MRI and mammography. All pts submitted to BM are prescribed at least one breast MRI to check for remaining breast tissue.

CONCLUSION

Our data reveal that even if, in general, BRCA1/2 women uptake preventive surgeries at a later age that recommended, we observed a strong adherence to radiological (most with breast MRI) surveillance. BA is the PS most frequently observed but, surprisingly for healthy women, most cases also underwent TH. BRCA2 healthy women uptaken bilateral mastectomy at an earlier age than BRCA1 women. It´s possible that BRCA1 women, when deciding for BM also decided for BA.

Citation Format: Priscila Nejo, Catarina Bexiga, S. Fragoso, A Mayer, S Santos, P Louro, A Luis, C Moura, Ana Clara, Fatima Vaz. Uptake of preventive surgeries in a prospective cohort of BRCA1/2 healthy women [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P6-08-36.

Adult peripheral blood and umbilical cord blood NK cells are good sources for effective CAR therapy against CD19 positive leukemic cells

Among hematological cancers, Acute Lymphoblastic Leukemia (ALL) and Chronic Lymphocytic Leukemia (CLL) are the most common leukemia in children and elderly people respectively. Some patients do not respond to chemotherapy treatments and it is necessary to complement it with immunotherapy-based treatments such as chimeric antigen receptor (CAR) therapy, which is one of the newest and more effective treatments against these cancers and B-cell lymphoma. Although complete remission results are promising, CAR T cell therapy presents still some risks for the patients, including cytokine release syndrome (CRS) and neurotoxicity. We proposed a different immune cell source for CAR therapy that might prevent these side effects while efficiently targeting malignant cells. NK cells from different sources are a promising vehicle for CAR therapy, as they do not cause graft versus host disease (GvHD) in allogenic therapies and they are prompt to attack cancer cells without prior sensitization. We studied the efficacy of NK cells from adult peripheral blood (AB) and umbilical cord blood (CB) against different target cells in order to determine the best source for CAR therapy. AB CAR-NK cells are slightly better at killing CD19 presenting target cells and CB NK cells are easier to stimulate and they have more stable number from donor to donor. We conclude that CAR-NK cells from both sources have their advantages to be an alternative and safer candidate for CAR therapy.

Influence of oxytocin receptor single nucleotide sequence variants on contractility of human myometrium: an in vitro functional study

Background

Oxytocin receptor (OXTR) gene variants have been shown to affect the prevalence of preterm birth, mode of delivery and oxytocin (OXT) requirements for labor induction and augmentation. We hypothesized that this might be associated with different myometrium responses to oxytocin. Our aim was to investigate the influence of a selection of eight OXTR gene single nucleotide variants on oxytocin-induced stimulation of human myometrium contractility in vitro.

Methods

Human myometrium biopsies were collected during elective cesarean sections at term, if patients had given informed consent. Myometrial strips were submerged under tension in an organ bath and allowed to contract; the remaining material was stored at − 80 °C for further determination of relevant genetics and mRNA level. The area under the curve (AUC) of all contractions taking place in the absence of OXT and of those occurring upon OXT addition (for 30 min each) was measured. OXT stimulation, defined as the ratio between AUC measurements after OXT addition and those in the absence of OXT was calculated for each strip. TaqMan™ Assays were used to detect the allele distribution of the eight OXTR variants and to determine the relative amounts of OXTR-mRNA in the samples. For each variant, oxytocin stimulation of contractility was compared between samples homozygous for the reference allele (reference group) and samples with at least one variant allele (variant group) by linear regression.

Results

Sixty samples were included in the present study. For rs1042778, rs11706648, rs4686301, rs53576, rs237895, and rs237902, OXT stimulation was similar in the reference and in the variant groups. However, the values of OXT stimulation differed significantly between the reference and the variant groups for rs4686302 (3.1 vs. 4.1 times; p = 0.022) and rs237888 (3.2 vs. 5.5 times; p = 0.001). No significant differences between the levels of OXTR-mRNA in the various reference and corresponding variant groups were detected.

Conclusions

Patients with variant alleles of rs237888 and/or rs4686302 may be more sensitive to oxytocin stimulation, explaining why these sequence variants have been associated with lower cesarean section prevalence and premature birth, respectively.

Bryophyllum pinnatum enhances the inhibitory effect of atosiban and nifedipine on human myometrial contractility: an in vitro study

BACKGROUND

The herbal medicine Bryophyllum pinnatum has been used as a tocolytic agent in anthroposophic medicine and, recently, in conventional settings alone or as an add-on medication with tocolytic agents such as atosiban or nifedipine. We wanted to compare the inhibitory effect of atosiban and nifedipine on human myometrial contractility in vitro in the absence and in the presence of B. pinnatum press juice (BPJ).

METHODS

Myometrium biopsies were collected during elective Caesarean sections. Myometrial strips were placed under tension into an organ bath and allowed to contract spontaneously. Test substances alone and at concentrations known to moderately affect contractility in this setup, or in combination, were added to the organ bath, and contractility was recorded throughout the experiments. Changes in the strength (measured as area under the curve (AUC) and amplitude) and frequency of contractions after the addition of all test substances were determined. Cell viability assays were performed with the human myometrium hTERT-C3 and PHM1-41 cell lines.

RESULTS

BPJ (2.5 μg/mL), atosiban (0.27 μg/mL), and nifedipine (3 ng/mL), moderately reduced the strength of spontaneous myometrium contractions. When BPJ was added together with atosiban or nifedipine, inhibition of contraction strength was significantly higher than with the tocolytics alone (p = 0.03 and p < 0.001, respectively). In the case of AUC, BPJ plus atosiban promoted a decrease to 48.8 ± 6.3% of initial, whereas BPJ and atosiban alone lowered it to 70.9 ± 4.7% and to 80.9 ± 4.1% of initial, respectively. Also in the case of AUC, BPJ plus nifedipine promoted a decrease to 39.9 ± 4.6% of initial, at the same time that BPJ and nifedipine alone lowered it to 78.9 ± 3.8% and 71.0 ± 3.4% of initial. Amplitude data supported those AUC data. The inhibitory effects of BPJ plus atosiban and of BPJ plus nifedipine on contractions strength were concentration-dependent. None of the test substances, alone or in combination, decreased myometrial cell viability.

CONCLUSIONS

BPJ enhances the inhibitory effect of atosiban and nifedipine on the strength of myometrial contractions, without affecting myometrium tissue or cell viability. The combination treatment of BPJ with atosiban or nifedipine has therapeutic potential.

P6324Contribution of muscle efficiency in heart failure patients post phase 2 cardiac rehabilitation

Background

Muscle efficiency (ME), can help explain the observed improvement in patients without increase in oxygen uptake (VO2) after cardiac rehabilitation programme (CRP). The better use of energy, independent to the oxygen delivery to muscle, may improve the functional capacity in Heart failure (HF) patients. Our aim was to evaluate the contribution of muscle efficiency improvement after CR on functional capacity.

Methods

We analyse consecutive patients data that had their phase 2 CR concluded, with HF as admission indication with no medical therapy changes and CRT implantation during this period. The aetiology of HF and biometric data, functional class, BNP, Minnesotta and EuroQol questionnaires and cardiorespiratory test pre and post 4 months of CRP were collected. The average of the exercise load in the first two and last two training sessions were recorded. ME was calculated at peak exercise during cardiopulmonary exercise test in pre and post CRP (see formula above).

Results

From 55 HF patients sequentially admitted in our CRP, during the last 24 months, 45 were included, since 2 were transplanted, 1 died and the 7 didn't concluded the program or not had all the data mentioned in the methods. The mean age was 60,5±10,3 years and 78% were male. Ischemic aetiology with depressed ejection fraction (64%) was the main admission indication, followed by cardiomyopathies (18%). Betablockers, ACEi or ARBs or ARNi and MRA were taken in 91%, 93%, 46%, respectively. ICD and CRT were previously implanted in 44% of the patients. Comparing pre and post CRP VO2 at peak exercise and aerobic threshold levels no statically differences were found. In this cohort 27 (60%) patients increased ME. At the end of the CRP, this group had a higher improvement in METs (p=0,021), higher gain in lean mass (p=0,041), in EuroQoL (p=0,002) and in physical dimension of Minnesotta questionnaire (p=0,032), when compared with patients that didn't improve the ME in at least 5%. In 22 patients that increased ME, the VO2 at aerobic threshold level didn't improve by at least 5% and in this group the same benefits were confirmed.

Formula of Muscle Efficiency

Conclusions

The improvement in exercise load reached in the post CRP cardiopulmonary test, independently of possible cardiac output changes (VO2 peak), seems to be explained in part by the increase in ME improvement.

P3747Does pulmonary vein isolation have similar results for treating AF in Chagas disease?

Background

AF is reported in up to 20% of patients with Chagas, a prevalent disease in Latin-America. PV isolation (PVI) in the cornerstone of AF ablation. However, in Chagas cardiopathy (ChC), microvascular and autonomic abnormalities, atrial fibrosis and sinoatrial dysfunction are possible mechanisms of AF. Therefore, the results of PVI may be different in this subgroup.

Objectives

To describe long-term results of AF ablation in pts with Chagas versus non-Chagas disease (ChC x NonCh) and evaluate risk factors for post-ablation recurrence.

Methods

This is a prospective, single-center study that included pts with nonvalvular AF who underwent PVI between 2013 and 2016. All procedures were guided by eletroanatomic mapping and intracardiac echocardiogram. Categorical variables were analyzed using chi-square test and numerical variables with t-student test. Binary logistic regression was performed to identify independent predictors of recurrence of any sustained atrial tachyarrhythmias.

Results

Ablation was performed in 160 pts (54±15 yo, 59% male): 42 pts with ChC (26%, 62±8 yo) and 118 NonChC (74%, 53±15 yo; p<0,001)). There was no difference in AF type (38x34% paroxysmal, 42x43% persistent, and 19x23% long-term persistent, p=NS) and left atrium diameter (38±5 vs 40±8mm, p=NS). In ChC the mean CHADSVASC score was higher (2.4 vs 1.4, p<0,001) and LVEF was lower (52±18% vs 64±8%, p=0.02). After a follow-up of 31±14 mo and 1.1 ablation per group, recurrence of AF/AT was higher in ChC (33% vs 14%, p=0.03) although more pts with Chagas were on AAD (71 vs 31%, p<0,001). During follow-up, occurrence of embolic events and cardiac or all-cause mortality were not different between groups (0% vs 1.7%, p=NS and 2.4 vs 1.7% p=NS; for ChC vs and NonChC, respectively).

At multivariate analysis, long-term persistent AF, hypertension and Chagas disease (HR= 2.21, 3.36 and 3.16, respectively) were independent predictors of recurrence.

Conclusions

Chagas disease is an independent predictor of recurrence after PVI. Further studies should address which strategy is more appropriate to this group of patients.

Load-bearing function of the colorectal submucosa and its relevance to visceral nociception elicited by mechanical stretch

Mechanical distension beyond a particular threshold evokes visceral pain from distal colon and rectum (colorectum), and thus biomechanics plays a central role in visceral nociception. In this study we focused on the layered structure of the colorectum through the wall thickness and determined the biomechanical properties of layer-separated colorectal tissue. We harvested the distal 30 mm of mouse colorectum and dissected this tissue into inner and outer composite layers. The inner composite consists of the mucosa and submucosa, whereas the outer composite includes the muscular layers and serosa. We divided each composite axially into three 10-mm-long segments and conducted biaxial mechanical extension tests and opening-angle measurements for each tissue segment. In addition, we quantified the thickness of the rich collagen network in the submucosa by nonlinear imaging via second-harmonic generation (SHG). Our results reveal that the inner composite is slightly stiffer in the axial direction, whereas the outer composite is stiffer circumferentially. The stiffness of the inner composite in the axial direction is about twice that in the circumferential direction, consistent with the orientations of collagen fibers in the submucosa approximately ±30° to the axial direction. Submucosal thickness measured by SHG showed no difference from proximal to distal colorectum under the load-free condition, which likely contributes to the comparable tension stiffness of the inner composite along the colorectum. This, in turn, strongly indicates the submucosa as the load-bearing structure of the colorectum. This further implies nociceptive roles for the colorectal afferent endings in the submucosa, which likely encode tissue-injurious mechanical distension.NEW & NOTEWORTHY Visceral pain from distal colon and rectum (colorectum) is usually elicited from mechanical distension/stretch, rather than from heating, cutting, or pinching, which usually evoke pain from the skin. We conducted layer-separated biomechanical tests on mouse colorectum and identified an unexpected role of submucosa as the load-bearing structure of the colorectum. Outcomes of this study will focus attention on sensory nerve endings in the submucosa that likely encode tissue-injurious distension/stretch to cause visceral pain.

Maternal psychological distress during pregnancy and childhood cardio-metabolic risk factors

BACKGROUND AND AIMS

Previous studies suggest that psychological distress during pregnancy may lead to fetal developmental adaptations, which programme cardio-metabolic disease of the offspring. We examined the associations of maternal overall psychological distress, depression and anxiety during pregnancy with cardio-metabolic risk factors in 10-year-old children and explore potential sex-specific differences.

METHODS AND RESULTS

In a population-based prospective cohort study among 4,088 mothers and their children, information about overall psychological distress, including depression and anxiety was obtained through the Brief Symptom Inventory during pregnancy. We measured child blood pressure and heart rate and insulin, glucose, serum lipids and C-reactive protein blood concentrations at 10 years. Analyses were performed in the total group and in boys and girls separately. Psychological distress during pregnancy was associated with higher childhood heart rate among boys only (differences 0.34 (95% Confidence Interval (CI) 0.18, 0.50) standard deviation scores (SDS), 0.22 (95% CI 0.06, 0.38) SDS, 0.33 (95% CI 0.19, 0.48) SDS, for overall psychological distress, depression and anxiety, respectively). Maternal anxiety during pregnancy was associated with higher childhood triglycerides among girls (difference 0.35 (95% CI 0.17, 0.53) SDS). Maternal psychological distress was not associated with childhood blood pressure, cholesterol, insulin, glucose and C-reactive protein concentrations.

CONCLUSIONS

Maternal psychological distress may influence their offspring heart rate and triglycerides concentrations. Further studies are needed to replicate these findings and assess the long-term cardio-metabolic consequences of maternal psychological distress.

Differential biomechanical properties of mouse distal colon and rectum innervated by the splanchnic and pelvic afferents

Visceral pain is one of the principal complaints of patients with irritable bowel syndrome, and this pain is reliably evoked by mechanical distension and stretch of distal colon and rectum (colorectum). This study focuses on the biomechanics of the colorectum that could play critical roles in mechanical neural encoding. We harvested the distal 30 mm of the colorectum from mice, divided evenly into three 10-mm-long segments (colonic, intermediate and rectal), and conducted biaxial mechanical stretch tests and opening-angle measurements for each tissue segment. In addition, we determined the collagen fiber orientations and contents across the thickness of the colorectal wall by nonlinear imaging via second harmonic generation (SHG). Our results reveal a progressive increase in tissue compliance and prestress from colonic to rectal segments, which supports prior electrophysiological findings of distinct mechanical neural encodings by afferents in the lumbar splanchnic nerves (LSN) and pelvic nerves (PN) that dominate colonic and rectal innervations, respectively. The colorectum is significantly more viscoelastic in the circumferential direction than in the axial direction. In addition, our SHG results reveal a rich collagen network in the submucosa and orients approximately ±30° to the axial direction, consistent with the biaxial test results presenting almost twice the stiffness in axial direction versus the circumferential direction. Results from current biomechanical study strongly indicate the prominent roles of local tissue biomechanics in determining the differential mechanical neural encoding functions in different regions of the colorectum. NEW & NOTEWORTHY Mechanical distension and stretch-not heat, cutting, or pinching-reliably evoke pain from distal colon and rectum. We report different local mechanics along the longitudinal length of the colorectum, which is consistent with the existing literature on distinct mechanotransduction of afferents innervating proximal and distal regions of the colorectum. This study draws attention to local mechanics as a potential determinant factor for mechanical neural encoding of the colorectum, which is crucial in visceral nociception.

Impact of maternal body mass index and gestational weight gain on pregnancy complications: an individual participant data meta-analysis of European, North American and Australian cohorts

OBJECTIVE

To assess the separate and combined associations of maternal pre-pregnancy body mass index (BMI) and gestational weight gain with the risks of pregnancy complications and their population impact.

DESIGN

Individual participant data meta-analysis of 39 cohorts.

SETTING

Europe, North America, and Oceania.

POPULATION

265 270 births.

METHODS

Information on maternal pre-pregnancy BMI, gestational weight gain, and pregnancy complications was obtained. Multilevel binary logistic regression models were used.

MAIN OUTCOME MEASURES

Gestational hypertension, pre-eclampsia, gestational diabetes, preterm birth, small and large for gestational age at birth.

RESULTS

Higher maternal pre-pregnancy BMI and gestational weight gain were, across their full ranges, associated with higher risks of gestational hypertensive disorders, gestational diabetes, and large for gestational age at birth. Preterm birth risk was higher at lower and higher BMI and weight gain. Compared with normal weight mothers with medium gestational weight gain, obese mothers with high gestational weight gain had the highest risk of any pregnancy complication (odds ratio 2.51, 95% CI 2.31- 2.74). We estimated that 23.9% of any pregnancy complication was attributable to maternal overweight/obesity and 31.6% of large for gestational age infants was attributable to excessive gestational weight gain.

CONCLUSIONS

Maternal pre-pregnancy BMI and gestational weight gain are, across their full ranges, associated with risks of pregnancy complications. Obese mothers with high gestational weight gain are at the highest risk of pregnancy complications. Promoting a healthy pre-pregnancy BMI and gestational weight gain may reduce the burden of pregnancy complications and ultimately the risk of maternal and neonatal morbidity.

TWEETABLE ABSTRACT

Promoting a healthy body mass index and gestational weight gain might reduce the population burden of pregnancy complications.

Abstract P5-09-09: CHEK2: the third susceptibility BReast CAncer (BC) gene?

INTRODUTION:

Considered a medium penetrance gene, CHEK2 codes for a kinase that is a key component of the DNA damage-signaling pathway. CHEK2 pathogenic variants were previously associated with breast and colorectal families and also with Li-Fraumeni phenotypes. Next generation sequencing (NGS) allowed for systematic inclusion of CHEK2 into gene panels. In here, we characterize the growing subgroup of CHECK2 BC families identified through our multidisciplinary program.

METHODS: Identification and review of CHEK2 families identified between 01/2000-06/2018 (until 2014 only the c.1100delC was tested (MLPA, MRC Holland); since 2014 NGS methods used were either,Trusight Cancer sequencing panel (Illumina, San Diego, CA, USA) or BRCA MASTR Dx (Multiplicom, Niel, Belgium). Carriers were included in a prospective follow up program.

RESULTS: 3646 index pts consented on gene testing. Most hereditary families (HF) were BRCA1/2 (374) (92%) but among non-BRCA HF bigger subgroups were 16 CHEK2, 10 Tp53 and 5 PALB2 HF. All CHEK2 index pts were diagnosed with only 3 different pathogenic variants: c.1100delC (9) c.319+2T&gt;A (6) and c.593-1G&gt;T (1 case of the only male BC pt in all CHEK2 pedigrees).

Index pts: mostly (93,8%) to females, with a mean age at first cancer diagnosis of 39 years (yrs) (30-52), 62,5% between 30-39yrs. With the exception of a Non Hodgking's Lymphoma index case, all index pts had BC(93,8%), 68,8% of which were ductal carcinomas and 12,5% of intraductal, all strongly positive for the estrogen receptor. With a mean follow up of 8,26yrs (3-15), secondary cancer cases occurred in 37,5% of index pts (mostly, 12,5%, BC at a mean of 53yrs (41-59).

Family phenotypes: data form 98 relatives (53,5% females) revealed diagnoses of BC (31,6%), prostate (8,1%), colorectal (7,1%) cancers. Only 22,2% of family cancers were diagnosed before 50yrs.

VUS: Among several complex variants of unknown significance, c.1036C&gt;T;p.Arg346Cys co-segregates in a predominantly male family with 3 prostate, 1 male and 1 female BC.

DISCUSSION AND CONCLUSIONS:

In the Portuguese population, emerging recurrent pathogenic variants in the CHEK2 gene, make it the most important non-BRCA BC gene so far. Carriers are included in prospective follow up but non-CHEK2 relatives are a challenge to genetic testing, as well as pedigree review, that questions its classification as a medium penetrance gene (or suggest the role of modifier factors).

Citation Format: Gomes VL, Machado P, Fragoso S, Santos S, Coelho I, Parreira J, Rodrigues P, Rodrigues F, Clara A, Bento S, Luís A, Opinião A, Vaz F. CHEK2: the third susceptibility BReast CAncer (BC) gene? [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-09-09.