Mechanobiology of myeloid cells

Tissue-resident myeloid cells sense and transduce mechanical signals such as stiffness, stretch and compression. In the past two years, our understanding of the mechanosensitive signalling pathways in myeloid cells has significantly expanded. Moreover, it is increasingly clear which mechanical signals induce myeloid cells towards a pro- or anti-inflammatory phenotype. This is especially relevant in the context of altered matrix mechanics in immune-related pathologies or in the response to implanted biomaterials. A detailed understanding of myeloid cell mechanosensing may eventually lead to more effective cell-based immunotherapies for cancer, the development of mechanically inspired therapies to target fibrosis, and the engineering of safer implants. This review covers these recent advances in the emerging field of mechanoimmunology of myeloid cells.

Low major bleeding, pump thrombosis and death rates in continuous flow left ventricular assist devices patients with good anticoagulation control

Background

Continuous-flow left ventricular assist device (CF-LVAD) patients require anticoagulation with vitamin K antagonists (VKAs). Good versus suboptimal anticoagulation control expressed as high versus low time in target range (TTR) of international normalized ratio results in less clinical events in atrial fibrillation patients. However, data in CF-LVAD patients are lacking.

Purpose

To study the association between TTR and clinical events in patients with CF-LVAD as destination therapy.

Methods

Single-centre cohort study in patients receiving CF-LVAD between 2010–2021. Patients were followed from start of VKAs until outcome or end of follow-up. Outcomes were combined major adverse events, thromboembolisms, major bleedings, neurologic events and all-cause mortality. The TTR (low vs. high; <50% vs. >50%) was calculated during the overall study period and over 1-month periods by the Rosendaal-method. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated by Cox regression with time-dependent covariables, adjusted for confounding.

Results

74 patients were included; median age 63 years [interquartile range 58–68], 77% males and 60%ischemic heart failure. During 191 years follow-up, 39 combined major adverse events, 14 thromboembolisms, 21 major bleeding, 22 neurologic events and 38 deaths occurred. For 1-month periods, high TTR was associated with less combined major adverse events (HR 0.3 95% CI 0.2–0.7), major bleeding (HR 0.4 95% CI 0.2–1.1), thromboembolism (HR 0.3 95% CI 0.1–1.3) and death (HR 0.2 95% CI 0.1–0.5) (Table 1). Results considering the overall study period were similar.

Conclusion

Good anticoagulation compared with suboptimal control during 1-month and the overall study period in CF-LVAD patients with destination therapy is associated with lower rates of combined major adverse events, major bleedings, pump thrombosis and death.

Funding Acknowledgement

Type of funding sources: None.

Female-specific reference values for blood pressure and its relationship with subclinical echocardiographic findings in women with a history of preeclampsia: the Queen of Hearts study

Introduction

Hypertension is the most crucial modifiable risk factor for cardiovascular disease (CVD). Sex differences in what is considered optimal blood pressure (BP) might deviate from current sex-blinded guidelines for hypertension. In women, an obstetric history of preeclampsia relates to postpartum hypertension and substantially increases the risk of premature CVD.

Purpose

To establish female-specific reference values for BP in relatively young women and assess its association with subclinical aberrant echocardiographic findings in a high-risk female population.

Methods

Data was used from the Queen of Hearts study; a cross-sectional cohort study on early detection of heart failure among young women with a history of preeclampsia and a control group of low-risk healthy women with a history of uncomplicated pregnancy. The control group was used to non-parametrically establish reference values for BP (95th percentile). The association between the derived reference values and the risk of subclinical aberrant echocardiographic findings was evaluated in the former preeclamptic group using logistic regression. All women were admitted to a standardized cardiovascular assessment including transthoracic echocardiography and 30-minutes BP measurement. Subclinical echocardiographic findings included left ventricular (LV) hypertrophy (LVH), LV concentric remodelling (LCVR), diastolic dysfunction (DD) and impaired LV ejection fraction (LVEF, <55%).

Results

A total of 429 women in the healthy control group and 856 in the former preeclamptic group were included (44±8 and 38±8 years, respectively). In the healthy control group, 97.7% and 99.8% of women had a systolic (SBP) and diastolic BP (DBP) value below the European Society of Cardiology (ESC) guidelines for hypertension. Overall, the derived reference value for SBP and DBP in our control group was 133 and 82 mmHg, respectively. Age-specific reference curves are presented in Figure 1 and 2. In the subgroup of former preeclamptic women 10.4% and 14.6% had SBP and DBP levels above 133 mmHg and 82mmHg, respectively. In this group, the Odds Ratio (OR) for subclinical aberrant echocardiographic findings when having SBP ≥133mmHg was 5.3 (95% CI 2.3–12.3) for LVH, 1.4 (95% CI 0.6–3.2) for LVCR, 5.9 (95% CI 3.3–10.7) for DD and 1.3 (95% CI 0.3–6.0) for impaired LVEF. For DBP ≥82mmHg, the OR for LVH was 3.5 (95% CI 1.5–8.0), LVCR 1.3 (95% CI 0.6–2.7), DD 3.4 (95% CI 1.9–6.0) and impaired LVEF 1.5 (95% CI 0.4–5.3).

Conclusions

Upper limits for SBP and DBP values in current guidelines correspond with the value of less than 2% of women in our healthy (no pre-eclampsia) population. We derived new reference values with the upper limit corresponding with the upper 5th centile. Values above this level, even below decision limits for hypertension, are associated with abnormal subclinical cardiac function and geometry in a high-risk young female population.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Dutch Heart Foundation

POS0591 TREATMENTS TO PREVENT RHEUMATOID ARTHRITIS IN FIRST DEGREE RELATIVES: DEMOGRAPHIC AND PSYCHOLOGICAL PREDICTORS OF RISK TOLERANCES

Background

There is a growing research focus on the development of interventions to reduce risk of rheumatoid arthritis (RA) in at-risk groups.(1) RA patients’ first-degree relatives (FDRs) have an elevated risk of developing RA and are potential candidates for preventive interventions. Recent studies have quantified the preferences of at risk groups for preventive treatments.(2-4) Little is known about predictors of preference heterogeneity in this context.

Objectives

Assess the extent to which FDR characteristics and beliefs predict risk tolerances for preventive treatments.

Methods

Adult FDRs of patients with confirmed RA in the UK were invited to take part in a web-based survey. FDRs enrolled in a UK prospective cohort (PREVeNT-RA) were also invited. Survey development, including attribute selection and presentation, was informed by qualitative research, ranking surveys, literature review, and expert opinion including patient research partners. Respondents received information about RA, questions to check comprehension, and an introduction to the survey. Participants were asked to imagine they were experiencing arthralgia and had positive autoantibody tests indicating a 60% chance of developing RA within two years. Using a probabilistic threshold technique, participants made choices between no treatment (no benefit and no risks) or a preventive treatment option. Treatment options were defined by a fixed level of benefit (reduction in risk of RA from 60% to 20%) and varying levels of risks (Table 1). For each treatment risk, participants made a series of choices where the risk was systematically increased or decreased until they switched their choice. This procedure was repeated for each of the remaining risks. Participants also completed items assessing demographics, perceived risk of developing RA, health literacy, subjective numeracy, the Brief Illness Perception Questionnaire (IPQ) and the Beliefs about Medicines Questionnaire General (BMQ-G). The maximum acceptable risk (MAR) respondents were willing to accept for a 40% (60% to 20%) point risk reduction in developing RA was summarized across participants using descriptive statistics. Associations between MARs and participants’ characteristics and illness/medication beliefs were assessed using interval regression. Independent variables were dichotomized and effects coded.

Table 1.

Attributes and levels of treatment options

Treatment attributeLevels describing no treatment optionLevels describing treatment optionChance of developing RA60%20%Chance of mild side effects0%2%; 4%; 5%; 7% or 10%Chance of a serious infection due to treatment0%1%; 1.5%; 2%; 3% or 5%Chance of a serious side effect that is potentially irreversible0%0.001%; 0.01%; 0.02%; 0.05% or 0.1%

Results

289 FDRs (80 male) responded. The mean (SE) MAR for mild side effects, serious infection, and serious side effects was 29.08 (1.52), 9.09 (0.60) and 0.85 (0.27), respectively. Participants aged over 60 years were less tolerant of risk of serious infection than average (mean MAR - 2.06 (0.78)) and younger participants were more tolerant of risk of serious infection than average (mean MAR + 2.06 (0.78)). Risk of mild side effects was less acceptable to participants who perceived they were likely/very likely to develop RA (mean MAR - 3.34 (1.55)) than to those who did not (mean MAR + 3.34 (1.55)). Education level, health literacy, numeracy, IPQ and BMQ-G subscales were not predictors of risk tolerance.

Conclusion

Age and perceived risk of RA had a significant impact on FDRs’ tolerance for specific, but not all, included risks. Cognitive ability and beliefs about RA/medicine did not explain preference heterogeneity. This is informative for drug development and the development of tailored risk communication resources to support preventive approaches.

References

[1]Mankia et al. Ann Rheum Dis. 2021;80(10):1286-98.

[2]Simons et al. Ann Rheum Dis. 2021;80:96-7.

[3]Harrison et al. Plos One. 2009; 14(4): e0216075.

[4]Finckh et al. Curr Rheumatol Rep. 2016;18: 51.

Acknowledgements

On behalf of the PREFER project. PREFER received funding from the IMI 2 Joint Undertaking (grant No. 115966), which receives support from the EU’s Horizon 2020 research and innovation program and European Federation of Pharmaceutical Industries and Associations (EFPIA). K. Raza is supported by the NIHR Birmingham Biomedical Research Centre.

Disclosure of Interests

Gwenda Simons: None declared, Ellen Janssen Shareholder of: Johnson & Johnson, Employee of: Janssen Research and Development, Jorien Veldwijk: None declared, Rachael DiSantostefano Shareholder of: Johnson & Johnson, Employee of: Janssen Research and Development, Matthias Englbrecht Speakers bureau: Abbvie, Chugai, Eli Lilly, Novartis, Roche, Sanofi, Mundipharma, Paid instructor for: Abbvie, Chugai, Roche, Consultant of: Abbvie, Novartis, Roche, Sanofi, Grant/research support from: Roche, Chugai, Christine Radawski Shareholder of: Eli Lilly, Employee of: Eli Lilly, Larissa Valor: None declared, Jenny Humphreys: None declared, Ian N. Bruce: None declared, Brett Hauber Shareholder of: Pfizer Inc., Employee of: Pfizer Inc., Karim Raza Consultant of: Abbvie, Sanofi, Grant/research support from: Bristol Myers Squibb, Marie Falahee: None declared.

The forces driving cancer extracellular vesicle secretion

The discovery that cancer cells discharge vast quantities of extracellular vesicles (EVs), underscored the explosion of the EV field. A large body of evidence now supports their onco-functionality in an array of contexts; stromal crosstalk, immune evasion, metastatic site priming, and drug resistance - justifying therapeutic intervention. The current bottleneck is a lack of clear understanding of why and how EV biogenesis ramps up in cancer cells, and hence where exactly avenues for intervention may reside. We know that EVs also play an array of physiological roles, therefore effective anticancer inhibition requires a target distinct enough from physiology to achieve efficacy. Taking the perspective that EV upregulation may be a consequence of the tumor landscape, we examine classic mutational events and tumor characteristics for EV regulators. All the while, aiming to illuminate topics worth further research in therapeutic development.

RNF43 truncations trap CK1 to drive niche-independent self-renewal in cancer

Wnt/β-catenin signaling is a primary pathway for stem cell maintenance during tissue renewal and a frequent target for mutations in cancer. Impaired Wnt receptor endocytosis due to loss of the ubiquitin ligase RNF43 gives rise to Wnt-hypersensitive tumors that are susceptible to anti-Wnt-based therapy. Contrary to this paradigm, we identify a class of RNF43 truncating cancer mutations that induce β-catenin-mediated transcription, despite exhibiting retained Wnt receptor downregulation. These mutations interfere with a ubiquitin-independent suppressor role of the RNF43 cytosolic tail that involves Casein kinase 1 (CK1) binding and phosphorylation. Mechanistically, truncated RNF43 variants trap CK1 at the plasma membrane, thereby preventing β-catenin turnover and propelling ligand-independent target gene transcription. Gene editing of human colon stem cells shows that RNF43 truncations cooperate with p53 loss to drive a niche-independent program for self-renewal and proliferation. Moreover, these RNF43 variants confer decreased sensitivity to anti-Wnt-based therapy. Our data demonstrate the relevance of studying patient-derived mutations for understanding disease mechanisms and improved applications of precision medicine.

Combinatorial Immunotherapies for Metastatic Colorectal Cancer

Colorectal cancer (CRC) is one of the most frequent and deadly forms of cancer. About half of patients are affected by metastasis, with the cancer spreading to e.g., liver, lungs or the peritoneum. The majority of these patients cannot be cured despite steady advances in treatment options. Immunotherapies are currently not widely applicable for this disease, yet show potential in preclinical models and clinical translation. The tumour microenvironment (TME) has emerged as a key factor in CRC metastasis, including by means of immune evasion-forming a major barrier to effective immuno-oncology. Several approaches are in development that aim to overcome the immunosuppressive environment and boost anti-tumour immunity. Among them are vaccination strategies, cellular transplantation therapies, and targeted treatments. Given the complexity of the system, we argue for rational design of combinatorial therapies and consider the implications of precision medicine in this context.

Myiasis in einem ulzerierten spinozellulären Karzinom – ein Fall von „aided giant tumor neglect“

Eine 91-jährige Patientin mit einem vorbekannten metastasierten Mammakarzinom stellte sich in der Hochschulambulanz der Hautklinik aufgrund eines ulzerierten Kopfhauttumors von etwa 10 cm Durchmesser vor. Obwohl sie mit jüngeren Angehörigen gemeinsam ein Haus bewohnte, zeigte die Patientin Hinweise auf eine Verwahrlosung. Histologisch zeigte sich an der Kopfhaut ein spinozelluläres Karzinom. Zusätzlich wurden 12 Maden aus der Wunde entfernt. Im hier vorgestellten Fall konnte gezeigt werden, dass bei mangelnder Pflege durch Mitbewohner durchaus zwei „giant“ Tumore auch gleichzeitig auftreten können, deren Diagnose und Therapie lange Zeit verschleppt und die im Verlauf sogar mit Maden besiedelt werden können. Wir schlagen hierfür den Begriff „giant tumor neglect (GTN)“ oder „aided giant tumor neglect (AGTN)“ vor.

Abstract P2-10-19: Are the mitotic factors Mitotic Activity Index (MAI) and Phosphohistone 3 (PPH3) stronger prognostic proliferation factors than Ki67 in node-negative breast cancer?

Background: The prognostic value of proliferation in node-negative breast cancer, either in the form of Ki67 or as the main common denominator in different gene expression profiles, has become clearer over the last years. The St Gallen guidelines recommend the use of Ki67 to distinguish between the luminal A and luminal B-like subtypes. Also, data have shown that Ki67 can separate patients with histological grade 2 into two groups with significant difference in prognosis. However, there is no consensus on the methodology for Ki67, and genetic profiling is still expensive. Previous studies have shown a strong prognostic value of the mitosis- and late G2-specific proliferation factors Phosphohistone H3 (PPH3) and mitotic activity index (MAI) in node-negative breast cancer. The present study was set up to study the value of these two factors compared to Ki67, alone and combined.

Material and methods: In 221 consecutive premenopausal node-negative breast cancer patients, of whom 87% had received no adjuvant medical treatment, PPH3 was assessed on tissue microarray (TMA), and MAI on whole sections. TMA-data on Ki67 was already available. Cut-offs for MAI, PPH3, and Ki67 were predefined. Cox proportional hazards regression was used to model the impact of the prognostic factors on distant disease-free survival (DDFS). The follow-up was restricted to the first 5 years after diagnosis, a time period during which 34 patients developed distant recurrences.

Results: In univariate analysis the strongest prognostic proliferation factor for DDFS was MAI (HR 5.1 95%CI 2.4–11, p < 0.0001), followed by PPH3 (HR 3.7 95%CI 1.8–7.5, p < 0.0001), and Ki67 (HR 2.7 95%CI 1.3–5.4, p = 0.005). ER, PR, HER2, histological grade, and age were also significant prognostic factors. When adding PPH3 to MAI, the prognostic value of MAI was strengthened (HR 6.3 95%CI 2.6–15, p < 0.0001). This corresponded to a 5-year DDFS of 95% for the 57% of the patients who were low risk (95%CI 88–98%), and 71% (95%CI 60–80%) for the 43% high risk patients. Ki67 did however not add any prognostic value to MAI. When stratifying for ER status and histological grade, MAI was a significant prognostic factor in the ER+ patients (HR 15 95%CI 5.1–41, p < 0.0001), as well as in patients with histological grade 2 (HR 11 95%CI 3.2–38, p < 0.0001). In multivariate analysis including HER2, age, and ER, and one proliferation factor at a time, MAI was the only proliferation factor that added independent prognostic value (HR 3.6 95%CI 1.1–11, p = 0.028).

Discussion: The present study on node-negative breast cancer patients confirms the strong prognostic value of the proliferation factors MAI and PPH3, in all patients, and more specifically in ER+ patients, and patients with histological grade 2. The study also suggests that by combining two proliferation factors, MAI and PPH3, an even stronger prognostic value is found. Ki67 however, did not add any prognostic value to MAI. Taken together, MAI and PPH3, alone and in combination may be helpful for prognostic considerations and for selection of adjuvant medical treatment.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-10-19.

Flexible PLED displays and related technologies

Flexible, free shape displays are the enabling technology for new robust, lightweight, extremely thin, portable electronic devices. Polymer Light Emitting Diodes (PLED) are especially suited for these applications, due to their fast response time, low voltage, high luminous efficiency and viewing angle performance. On the other hand, PLED displays are extremely sensitive to moisture and oxygen. Substrate materials provided with high performance hermetic and conducting layers are therefore an essential component for manufacturing these flexible devices. Polymer based substrates provide the necessary mechanical flexibility; they also require several thin, brittle, functional inorganic layers such diffusion barriers and transparent electrodes. The structural integrity, dimensional stability and thermal properties of the substrate stack are crucial to insure device functionality and reliability. For polymer-based substrate several effects lead to dimensional variation of the substrates, such as solvent uptake, physical ageing of the polymer base, thermal expansion and stress induced deformations. These effects must be taken into account to successfully perform classic photolithographic steps.

Ink-jet printing is a critical enabling technology for flexible PLED displays, providing a customizable means to dispense solution-based polymers onto a flexible substrate, allowing for multi-color devices. On the other hand, IJP must meet several challenges, especially to comply with industrial applications. For example, accurate landing position of the droplets to form homogeneous hole-transport and electroluminescent layers as well as good wetting characteristic of the substrates must be obtained with reliable high throughput techniques.

Use of Receiver Operating Characteristic (ROC) Analysis To Determine the Most Optimal Prognostic Threshold for Adjuvant! in Lymph Node Negative Breast Cancer Patients < 55 Years

Background: Adjuvant!1 is a web based tool to predict the 10-year relapse free survival (RFS), breast cancer specific survival (BCSS) and overall survival (OS) probabilities using age, tumor size (pT), lymph node status (pN), histological grade (Grade 1-3), Estrogen receptor (ER) status in the estimation. A challenge is to find optimal cut-off values of the Adhuvant probabilities to compare the predictions with other prognostic factors.Patients and methods: In the Dutch nationwide Multicenter Morphometric Mamma Carcinoma Project 3472 patients have been enroled2, of which 516 <55 years with T1-3N0M0 underwent surgery and local radiation therapy when indicated. Adjuvant systemic treatment was not given according to the Dutch guidelines at that time. Median follow-up is 10 years. The 10-year RFS, BCSS and OS probabilities were evaluated with Adjuvant! Since these estimated predicted probabilities are continuous, optimal thresholds can be evaluated by the Receiver Operating Characteristic (ROC) analyses. Concordances between the Adjuvant predicted outcomes and, classical prognosticators were evaluated by the Spearman-correlation test.Results: The optimal cut-points for Adjuvant-RFS, Adjuvant-BCSS and Adjuvant-OS were 62% (Area Under the Curve=AUC==0.603, p=0.0004), 86% (AUC=0.635, p=0.0001) and 72% (AUC=0.598, p=0.0002) respectively. Using these thresholds, a moderate correlation was found between all the Adjuvant! endpoints and pT, Grade 1-3 and ER status (r=0.34 – 0.63). In the univariate survival analysis (Kaplan Meier) the above Adjuvant thresholds were highly prognostic. For Adjuvant-RFS >63/≤63 the 14-year survival was 77% and 64% respectively (p=0.001; log-rank). Moreover, for Adjuvant-BCSS (≥86/<86) the corresponding numbers were 82% and 67% ( P < 0.0001; log-rank). For Adjuvant-OS (≥72/<72) the survivals were 77% and 64% respectively (p<0.0001; log-rank). With multivariate analyses, Adjuvant! variables were part of the model only for BCSS and OS. However, Grade1-3 was prognostically stronger than Adjuvant! regarding both BCSS and OS. Furthermore, when the three features that constitute grade (tubular formation, nuclear atypia and mitosis count), only the latter was included in the final model.Discussion: ROC analysis can obtain optimal prognostic threshold values from web-based prognostic tools using time dependent endpoints3. A high grade of dependency between Adjuvant! and its’ underlying variables must be taken into account when the multivariate model is put up. Mitotic activity in the tumor seems to overrule Adjuvant!. This should be further explored.1 www.adjuvantonline.com2 Baak JPA, et al.: Pathol Res Pract 185:664-70, 19893 Zlobec I, et al.:J Clin Pathol 60:1112-1116, 2007.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3178.

Mitotic Activity Index Identifies Both Over- and Undertreated Lymph Node Negative Breast Cancer Patients < 55 Year According to the Norwegian Treatment Guidelines

Background: It is a challenge to avoid under- and overtreatment of breast cancer patients in the adjuvant setting. Patients who have not received adjuvant systemic treatment and with a known outcome demonstrate the natural course of the disease after surgery. Such patients may be re-evaluated in specific guidelines like the Norwegian Breast Cancer Group (NBCG) based on the St. Gallen criteria. NBCG classify the patients in a low-risk group which should not receive systemic treatment, and a high-risk group which should be offered such therapy. New factors may be evaluated in these two strata, possibly discriminating groups of under- or overtreated patients. The aim of this study was to explore if the previous established marker of proliferation, the mitotic activity index (MAI), could give any additional information.Patients and methods: The study comprised 516 lymph node negative patients < 55 years from the Dutch prospective Multicenter Morphometric Mammary Carcinoma Project (MMMCP; 1987-1989)1. No adjuvant systemic treatment was given after surgery to these patients. The guidelines from NBCG-2005 were used to classify the patients in “NBCG low-risk” group (n=100) defined as pT1/Grade 1, all ages and pT1a-b/Grade 2-3, >35 years, all hormone receptor positive. The rest of the patients (n=416) was grouped as “NBCG high-risk”. Breast Cancer Specific Survival (BCSS) was estimated by the Kaplan-Meier method. MAI was analyzed after a standardized protocol in the invasive front of the tumor. The previous established thresholds of MAI with low (<3), intermediate (3-9) and high (≥10) proliferation were used in the calculations.Results: In the “NBCG low-risk” group 10 % of the patients had MAI ≥10. These had a 14-years BCSS of 50 % (HR=15.47, 95 % CI=3.61-66.30) and may be regarded as undertreated patients. Patients with MAI <3 and 3-9 had a BCSS of 95 % and 83 % respectively. In the “NBCG high-risk”group 24 % of the patients with MAI<3 had a 14-years BCSS of 92 % indicating overtreatment. Furthermore, patients with MAI 3-9 and ≥10 had a BCSS of 74 % and 63 % (p-trend <0.0001).Discussion: MAI represents the “converging mitotic drive” from all cellular signal pathways in the peripheral growing zone of the tumor, where also micro-environmental factors are known to influence proliferation of cancer cells. This may explain why MAI gives original information strong enough to identify subgroups breast cancer patients who would not get optimal adjuvant treatment. A disadvantage of this study is that the HER-2 status in this MMMCP material is not known. National prospective studies are needed to verify our results.1 Baak, JPA et al: Pathol Res Pract 185:664-70,1989.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3182.

[Drug related deaths in France. A critical view]

BACKGROUND

Available data suggest a reduction in the number of overdoses due to psychoactive substances (tobacco and alcohol excluded) in France. Nevertheless, official levels remain considerably low compared to other European countries, and strong differences between the different sources providing information support the hypothesis of under-reporting.

METHODS

Two cross-tabulations of the main sources of information (police data and national mortality registry on one hand; police data and on another hand) allow the use of easy-to-compute, capture-recapture based indicators to estimate the invisible population (i.e. hidden overdoses).

RESULTS

Results support a significant under-reporting of overdoses, reaching a minimum level of 30%.

CONCLUSION

Unlike official claims, there has been a rise in overdoses in France during the last decade. Besides the applied corrections, levels of overdoses still remain low. Attention should be paid to death certification. Other issues of interest are the lack of a common definition and the need for greater institutional coordination.

TLR signaling pathways: opportunities for activation and blockade in pursuit of therapy

The identification of the TLRs as key sensors of microbial infection has presented a series of new targets for drug development. The TLRs are linked to the most powerful inflammatory pathways in mammals. The question arises from the start: do we wish to stimulate TLR signaling in order to eradicate specific infections and/or neoplastic diseases? Or do we wish to block TLR signaling to treat inflammatory diseases? If we accept that it would be useful to modulate TLR signaling, the next step is to identify the correct molecular target(s) for the task. Perhaps it might even be possible to exercise selectivity, modulating some aspects of TLR signaling and not others. Classical and reverse genetic analyses offer insight into the possibilities that exist, and point to specific checkpoints within signaling pathways at which modulation might normally be imposed.

Identification of Lps2 as a key transducer of MyD88-independent TIR signalling

In humans, ten Toll-like receptor (TLR) paralogues sense molecular components of microbes, initiating the production of cytokine mediators that create the inflammatory response. Using N-ethyl-N-nitrosourea, we induced a germline mutation called Lps2, which abolishes cytokine responses to double-stranded RNA and severely impairs responses to the endotoxin lipopolysaccharide (LPS), indicating that TLR3 and TLR4 might share a specific, proximal transducer. Here we identify the Lps2 mutation: a distal frameshift error in a Toll/interleukin-1 receptor/resistance (TIR) adaptor protein known as Trif or Ticam-1. Trif(Lps2) homozygotes are markedly resistant to the toxic effects of LPS, and are hypersusceptible to mouse cytomegalovirus, failing to produce type I interferons when infected. Compound homozygosity for mutations at Trif and MyD88 (a cytoplasmic TIR-domain-containing adaptor protein) loci ablates all responses to LPS, indicating that only two signalling pathways emanate from the LPS receptor. However, a Trif-independent cell population is detectable when Trif(Lps2) mutant macrophages are stimulated with LPS. This reveals that an alternative MyD88-dependent 'adaptor X' pathway is present in some, but not all, macrophages, and implies afferent immune specialization.

Adenylate kinase phosphotransfer communicates cellular energetic signals to ATP-sensitive potassium channels

Transduction of energetic signals into membrane electrical events governs vital cellular functions, ranging from hormone secretion and cytoprotection to appetite control and hair growth. Central to the regulation of such diverse cellular processes are the metabolism sensing ATP-sensitive K+ (K(ATP)) channels. However, the mechanism that communicates metabolic signals and integrates cellular energetics with K(ATP) channel-dependent membrane excitability remains elusive. Here, we identify that the response of K(ATP) channels to metabolic challenge is regulated by adenylate kinase phosphotransfer. Adenylate kinase associates with the K(ATP) channel complex, anchoring cellular phosphotransfer networks and facilitating delivery of mitochondrial signals to the membrane environment. Deletion of the adenylate kinase gene compromised nucleotide exchange at the channel site and impeded communication between mitochondria and K(ATP) channels, rendering cellular metabolic sensing defective. Assigning a signal processing role to adenylate kinase identifies a phosphorelay mechanism essential for efficient coupling of cellular energetics with K(ATP) channels and associated functions.

Allogeneic recombinant soluble MHC class I molecules modify urinary odor cues in rats

The highly polymorphic genes of the major histocompatibility complex (MHC) determine, in part, the odor cues and behavior of an individual. In animal models, MHC-associated odors that regulate distinct behavior have been identified mainly in urine. However, the underlying mechanism is still not clear. Here, we show that injected recombinant soluble (rs) MHC class I molecules (DA, rsRT1.A(a) and Lewis, rsRT1.A(l)) temporarily alter urine odor of Lewis test rats (RT1.A(l)). This change in urinary signals was observed in behavioral assays using the habituation/dishabituation test and in odor signals analysed by gas chromatography (GC) and mass spectrometry (MS). Gas chromatographic analysis revealed that these altered odor signals are caused by quantitative changes of at least two nitrogen-containing urinary compounds. The results suggest that urinary olfactory cues are directly or indirectly influenced by MHC class I gene products.

Compromised energetics in the adenylate kinase AK1 gene knockout heart under metabolic stress

Rapid exchange of high energy carrying molecules between intracellular compartments is essential in sustaining cellular energetic homeostasis. Adenylate kinase (AK)-catalyzed transfer of adenine nucleotide beta- and gamma-phosphoryls has been implicated in intracellular energy communication and nucleotide metabolism. To demonstrate the significance of this reaction in cardiac energetics, phosphotransfer dynamics were determined by [(18)O]phosphoryl oxygen analysis using( 31)P NMR and mass spectrometry. In hearts with a null mutation of the AK1 gene, which encodes the major AK isoform, total AK activity and beta-phosphoryl transfer was reduced by 94% and 36%, respectively. This was associated with up-regulation of phosphoryl flux through remaining minor AK isoforms and the glycolytic phosphotransfer enzyme, 3-phosphoglycerate kinase. In the absence of metabolic stress, deletion of AK1 did not translate into gross abnormalities in nucleotide levels, gamma-ATP turnover rate or creatine kinase-catalyzed phosphotransfer. However, under hypoxia AK1-deficient hearts, compared with the wild type, had a blunted AK-catalyzed phosphotransfer response, lowered intracellular ATP levels, increased P(i)/ATP ratio, and suppressed generation of adenosine. Thus, although lack of AK1 phosphotransfer can be compensated in the absence of metabolic challenge, under hypoxia AK1-knockout hearts display compromised energetics and impaired cardioprotective signaling. This study, therefore, provides first direct evidence that AK1 is essential in maintaining myocardial energetic homeostasis, in particular under metabolic stress.

Adenylate kinase 1 gene deletion disrupts muscle energetic economy despite metabolic rearrangement

Efficient cellular energy homeostasis is a critical determinant of muscle performance, providing evolutionary advantages responsible for species survival. Phosphotransfer reactions, which couple ATP production and utilization, are thought to play a central role in this process. Here, we provide evidence that genetic disruption of AK1-catalyzed ss-phosphoryl transfer in mice decreases the potential of myofibers to sustain nucleotide ratios despite up-regulation of high-energy phosphoryl flux through glycolytic, guanylate and creatine kinase phosphotransfer pathways. A maintained contractile performance of AK1-deficient muscles was associated with higher ATP turnover rate and larger amounts of ATP consumed per contraction. Metabolic stress further aggravated the energetic cost in AK1(-/-) muscles. Thus, AK1-catalyzed phosphotransfer is essential in the maintenance of cellular energetic economy, enabling skeletal muscle to perform at the lowest metabolic cost.

The dual control model of male sexual response: a theoretical approach to centrally mediated erectile dysfunction

A theoretical model of dual control of male sexual response is considered, based on the balancing of central excitation and inhibition, with individuals varying in their propensity for both sexual excitation and inhibition of sexual response. A questionnaire method for measuring propensities for sexual excitation and inhibition has been developed (SIS/SES questionnaire), resulting in one excitation factor (SES) and two inhibition factors (SIS1 and SIS2). Evidence for the existence of both inhibitory and excitatory tone is discussed. The first inhibition factor (SIS1) may be related to level of inhibitory tone and is associated with fear of performance failure. The second inhibition factor (SIS2) may be related to external threats (e.g. from within the sexual relationship). The implications for the treatment of centrally mediated erectile dysfunction are discussed, with predictions that high SIS2 individuals will respond to psychological treatment, whereas high SIS1 individuals will respond better to pharmacological methods of treatment.

Effects of fragrance on female sexual arousal and mood across the menstrual cycle

The effects of fragrance on sexual response in women were investigated using subjective and physiological measures of sexual arousal and of mood. Responses were obtained from female participants in three different fragrance conditions (female fragrance, male fragrance, and a "blank" or neutral substance), as they viewed erotic and sexually neutral films, and fantasized about sexual situations. Each woman was tested twice: during the midfollicular and periovulatory phases of her menstrual cycle. Menstrual cycle phase effects were apparent; self-report data indicated greater sexual arousal and more positive mood during the periovulatory than during the follicular phase. Results demonstrated a positive effect of the male fragrance on genital arousal during erotic fantasy, but this finding was apparent only during the follicular phase testing session. This effect did not appear to be mediated by any effects of fragrance on mood.

How does the major histocompatibility complex influence behavior?

The major histocompatibility complex (MHC) encodes highly polymorphic cell surface glycoproteins that form the basis of immunological individuality. It has been postulated that MHC besides its role in immune defence also determines behavior through formation of specific odor cues. In addition several studies have implicated MHC disassortative odor and mating preferences in mice, rats, and humans. Further leading studies have suggested that mice and humans prefer to mate with MHC dissimilar individuals. Although the latter remains controversial, MHC dependent mating preferences provide a potentially important selective factor driving the polymorphisms of the MHC genes. Here we review some of the available data and hypotheses on the influence of the MHC on behavior and discuss its molecular and chemical basis.

Purified truncated recombinant HLA-B7 molecules abrogate cell function in alloreactive cytotoxic T lymphocytes by apoptosis induction

BACKGROUND

Soluble MHC class I molecules are ubiquitous in human body fluids, including serum, urine, sweat, and cerebrospinal fluid. However, their biological function has remained unresolved. Membrane-derived human soluble MHC molecules (soluble human leukocyte antigen; sHLA) have been shown to induce apoptosis in alloreactive cytotoxic T lymphocytes (CTL). Here we report the efficacy of recombinant soluble HLA-B7 (rsHLA-B7) to modulate T-cell function.

METHODS

Primers of HLA-B7 were designed to allow amplification of a cDNA lacking the transmembrane and cytoplasmic domains yielding a truncated gene. rsHLA-B7 molecules were expressed in the human myeloma cell line 721.221 and purified by affinity chromatography using the BB7.7 mouse monoclonal antibody. CTL were generated from peripheral blood lymphocytes derived from healthy blood donors by stimulation with irradiated Epstein Barr virus-transformed HLA-B7-positive B cells. CTL were preincubated with rsHLA-B7, and cytotoxicity and apoptosis were tested according to standard procedure.

RESULTS

A total of 2 x 10(6) cells/ml secreted 10 microg/ml rsHLA-B7 as determined by a conformation-dependent ELISA, suggesting that rsHLA-B7 do not require the transmembrane and cytoplasmic regions for proper folding. After purification by affinity chromatography, rsHLA-B7 induced apoptosis in anti-HLA-B7 CTL, but not in anti-HLA-A2-specific, CTL. As a consequence, allorecognition of target cells by the CTL was significantly blocked.

CONCLUSION

Recombinant sHLA are sufficient binding cues for T cells, which efficiently induce apoptosis and block allorecognition of target cells by CTL. Thus, recombinant sHLA molecules may become a valuable new modality for specific immunological therapeutic intervention.

[Histopathological findings in the proprioception of the shoulder joint]

Purpose of this study was the evaluation of distribution and morphology of mechanoreceptors in the glenohumeral joint capsule and rotator cuff in comparison to the coracoacromial ligament by means of specific immunfluorescence microscopy. The complemente joint capsules, rotator cuffs and coracoacromial ligaments of three fresh cadaver shoulder were harvesed. Serial cryostate sections were taken and alternately incubated with antiserum against neurofilament, lamin or myelin of peripheral nerves. The antibody-reaction was visualized with fluorescin lg-G. The nerve endings were photographed and computer-aided 3-dimensional reconstructions were performed. Three types of corpuscular and free nerve endings of different morphology were found in different distributions: whereas the Ruffini corpuscles were much more frequent in the coracoacromial ligament and rotator cuff, Pacini endings were predominantly found in the joint capsule. Generally corpuscular nerve endings were more frequent in the coracoacromial ligament and the rotator cuff than in the antero-inferior capsule and the number of corpuscles increased from medial to lateral within the anterior and inferior parts of the capsule. The dense ligamentous tissue was almost aneural whereas the periarticular fatty or loose connective tissue contained nerve fibres and nerve endings. In view of the results of other experimental and clinical studies the high frequency of Ruffini and Pacini endings in the rotator cuff and coracoacromial ligament suggest, that both are involved in the neurosensory control of glenohumeral stability and subacromial impingement. In contrast our findings in the joint capsule do not clearly prove, that those joint receptors predominantly maintain joint stability.

Asking for the indicator function of bioassays evaluating soil contamination: are bioassay results reasonable surrogates of effects on soil microflora?

In evaluating the biological effect of solid materials like soil a bacterial contact assay often shows higher sensitivity than elutriate testing. Results of the Bacillus cereus contact assay for some environmental important toxicants are presented in this article. A comparison with another heterotrophic soil bacterium, Arthrobacter globiformis, shows comparable sensitivity. In a bioassay approach organisms at the level of individuals or populations are exposed to soil material to determine the significance of contaminants. An investigation that incorporates community level processes in comparison with toxicity test results provides a better understanding of the indicator function of bioassays. Comparison of soil bioassays (aqueous and solid phase) with ecological parameters demonstrates the problems in predicting ecological effects of soil contamination.