Coronary artery calcium score in people living with HIV. Results from the French CAC study

Background

People living with HIV (PLWH) have a higher risk of CAD. Whether coronary artery calcification (CAC) score could better stratify the CV risk remains debated in this middle age population.

Purpose

We conducted the French CAC score study to compare the CAC score between PLHIV and HIV− subjects at intermediate risk.

Methods

689 subjects (257 PLHIV and 432 HIV−) were consecutively addressed for CV risk evaluation including CAC score assessment in 2 centers between 2013 and 2019. Subjects were included if they were 18 years'old or older, had no known cardiovascular disease and had a CAC score along with cardiometabolic assessment.

Results

The mean age of the cohort was 59.3 years ± 10.7 and predominantly male (54%). PLHIV were younger (55.8 years ± 9.1 vs 61.3±11.3, p<0.004), with a lower rate of diabetics (18% vs 26%, p=0.009) and lower levels of total cholesterol, LDLc, and HDLc (2.0 mmol/l vs, 2.2 mmol/l; 1.2 mmol/L vs 1.3 mmol/L; and 1.2 mmol/L vs 1.4 mol/L respectively, all p<0.001). The prevalence of hypertension, dyslipidemia and obesity was similar between PLHIV and the HIV− group (40%, 43% and 21%, respectively). No differences were observed in CV therapies prescribed including antihypertensive drugs and statins between PLHIV and the HIV− group (39% vs 37%, p=0.54 and 46% vs 39%, p=0.065). In contrast, PLHIV had higher rate of triglycerides (1.4 mmol/L vs 1.2 mmol/L, p=0.01), higher rate of active smoking (28% vs 14%, p<0.001), CRP level (4.0 mg/L vs 2.9 mg/L, p<0.001) along with higher black ethnicity representation (17% vs 5%;, p<0.001). 96% of PLHIV were under antiretroviral therapy at the time of enrollment with 88% who had been exposed to protease inhibitors. In subjects who had carotid and/or limb ultrasound evaluation (67% and 45% respectively in PLHIV and HIV), no increased rate of arterial stenosis >50% was found (13% vs 8%, p=0.16). Concerning, CV risk estimation using 10-year ASCVD and HEART scores, we observed that the median ASCVD score was similar between PLHIV and HIV− group (10.7% vs 9.8, p=0.15) but that PLHIV had a higher HEART score (3.0% vs 2.0%, p<0.001). The repartition between the ASCVD or HEART scores classes between the 2 groups was similar with 80% of the cohort classified as low or intermediate CV risk with the ASCVD score and 88% at intermediate or borderline CV risk with the HEART score. However, no statistically significant differences was found between the 2 groups regarding the prevalence of CAC = 0 (41% vs 44%, p=0.52) and the median CAC score (7.7 vs 8.2, p=0.81).

Conclusion

In this cohort of subjects at intermediate CV risk according to CV risk scores estimation (ASCVD or HEART scores), PLHIV had a similar prevalence of CAC = 0 and median CAC scores as compared to HIV− subjects despite a younger age (6 years). Longitudinal follow up will explore whether this similar CAC score evaluation will be translated into higher CV events.

Funding Acknowledgement

Type of funding sources: None.

“A sorrow shared …”: a qualitative content analysis of what couples with recurrent miscarriages expect from one another and their families and friends

STUDY QUESTION

When couples have to face recurrent pregnancy loss (RPL), what are the partners’ wishes and needs and what is their perception of helpful and unhelpful factors with regard to their own, their partners’ and their families’ and friends’ ways of dealing with the problem?

SUMMARY ANSWER

Women and men with repeated miscarriages want open communication about their losses, but expect a sensitive and empathetic attitude from others, not pity or trivialization.

WHAT IS KNOWN ALREADY

RPL not only causes the women affected and their partners considerable emotional distress; it also has an impact on the couples’ relationships and the way they relate to their families and friends. Studies suggest that women have a greater need than their male partners to talk about their losses and that these differences may lead to dissatisfaction and cause relational tension. In addition, men often assume a ‘mainstay’ role, supporting their partners and displaying fortitude in the face of distress. As yet, however, little research has been conducted so far on the question of what the members of couples with RPL expect from one another and from their families and friends.

STUDY DESIGN, SIZE, DURATION

The study sample consisted of 147 couples and 17 women with at least 2 miscarriages attending the special unit for RPL at the University Women’s Hospital in Heidelberg (Germany) for the first time between September 2018 and October 2020 (response rate: 82.7%). The patients were asked to participate in this combined qualitative and questionnaire study.

PARTICIPANTS/MATERIALS, SETTING, METHODS

In order to explore the wishes and needs of those affected in more detail, the free text responses obtained were examined in this study by using qualitative content analysis. Categories and subcategories were created inductively to summarize and systematize content.

MAIN RESULTS AND THE ROLE OF CHANCE

Patients affected by RPL want their partners and their families and friends to deal with the topic openly and empathically. In the partnership itself, acceptance of individual grieving modes and sharing a common goal are important factors. Men, in particular, want their partners to be optimistic in facing up to the situation. Regarding communication with family and friends, it transpired that ‘good advice’, playing the matter down, inquiries about family planning, pity and special treatment are explicitly not appreciated.

LIMITATIONS, REASONS FOR CAUTION

The sample was a convenience sample, so self-selection effects cannot be excluded. In addition, the level of education in the sample was above average. Accordingly, the sample cannot be regarded as representative. The results of the content analysis are based on the respondents’ written answers to open-ended questions in the questionnaire. Unlike qualitative interview studies, further questioning was not possible in the case of ambiguities or to request more details.

WIDER IMPLICATIONS OF THE FINDINGS

Frank and sincere communication about miscarriages and about one’s own emotions and needs should be promoted both in the partnership and among family members and friends in order to strengthen the potential of social support as a resource. Open communication about the different needs of both partners is necessary to create mutual understanding. The results show the importance not only of empathy and consideration for the couples concerned but also their desire not to be pitied. Striking a fine balance between fellow-feeling and pity may also lead to tension, and this potential dilemma should be addressed in psychosocial counselling. Overall, the study contributes to a better understanding of what couples want from their families and friends when they are attempting to come to terms with RPL and highlights potential challenges in the interaction between affected couples and their families and friends.

STUDY FUNDING/COMPETING INTEREST(S)

No funding was received for this study. None of the authors declared any conflicts of interest.

TRIAL REGISTRATION NUMBER

DRKS00014965.

Evaluation of malignant effusions using MR-based T1 mapping

Our aim was to investigate the diagnostic yield of rapid T1-mapping for the differentiation of malignant and non-malignant effusions in an ex-vivo set up. T1-mapping was performed with a fast modified Look-Locker inversion-recovery (MOLLI) acquisition and a combined turbo spin-echo and inversion-recovery sequence (TMIX) as reference. A total of 13 titrated albumin-solutions as well as 48 samples (29 ascites/pleural effusions from patients with malignancy; 19 from patients without malignancy) were examined. Samples were classified as malignant-positive histology, malignant-negative histology and non-malignant negative histology. In phantom analysis both mapping techniques correlated with albumin-content (MOLLI: r = − 0.97, TMIX: r = − 0.98). MOLLI T1 relaxation times were shorter in malignancy-positive histology fluids (2237 ± 137 ms) than in malignancy-negative histology fluids (2423 ± 357 ms) as well as than in non-malignant-negative histology fluids (2651 ± 139 ms); post hoc test for all intergroup comparisons: < 0.05. ROC analysis for differentiation between malignant and non-malignant effusions (malignant positive histology vs. all other) showed an (AUC) of 0.89 (95% CI 0.77–0.96). T1 mapping allows for non-invasive differentiation of malignant and non-malignant effusions in an ex-vivo set up.

Medicine in motion: Opportunities, challenges and data analytics-based solutions for traditional medicine integration into western medical practice

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional pharmacopeias have been developed by multiple cultures and evaluated for efficacy and safety through both historical/empirical iteration and more recently through controlled studies using Western scientific paradigms and an increasing emphasis on data science methodologies for network pharmacology. Traditional medicines represent likely sources of relatively inexpensive drugs for symptomatic management as well as potential libraries of new therapeutic approaches. Leveraging this potential requires hard evidence for efficacy that separates science from pseudoscience.

MATERIALS AND METHODS

We performed a review of non-Western medical systems and developed case studies that illustrate the epistemological and practical translative barriers that hamper their transition to integration with Western approaches. We developed a new data analytics approach, in silico convergence analysis, to deconvolve modes of action, and potentially predict desirable components of TM-derived formulations based on computational consensus analysis across cultures and medical systems.

RESULTS

Abstraction, simplification and altered dose and delivery modalities were identified as factors that influence actual and perceived efficacy once a medicine is moved from a non-Western to Western setting. Case studies on these factors highlighted issues with translation between non-Western and Western epistemologies, including those where epistemological and medicinal systems drive markets that can be epicenters for zoonoses such as the novel Coronavirus. The proposed novel data science approach demonstrated the ability to identify and predict desirable medicinal components for a test indication, pain.

CONCLUSIONS

Relegation of traditional therapies to the relatively unregulated nutraceutical industry may lead healthcare providers and patients to underestimate the therapeutic potential of these medicines. We suggest three areas of emphasis for this field: First, vertical integration and embedding of traditional medicines into healthcare systems would subject them to appropriate regulation and evidence-based practice, as viable integrative implementation mode. Second, we offer a new Bradford-Hill-like framework for setting research priorities and evaluating efficacy, with the goal of rescuing potentially valuable therapies from the nutraceutical market and discrediting those that are pseudoscience. Third, data analytics pipelines offer new capacity to generate new types of TMS-inspired medicines that are rationally-designed based on integrated knowledge across cultures, and also provide an evaluative framework against which to test claims of fidelity and efficacy to TMS made for nutraceuticals.

In vitro exposure to Hymenoptera venom and constituents activates discrete ionotropic pathways in mast cells

Calcium entry is central to the functional processes in mast cells and basophils that contribute to the induction and maintenance of inflammatory responses. Mast cells and basophils express an array of calcium channels, which mediate responses to diverse stimuli triggered by small bioactive molecules, physicochemical stimuli and immunological inputs including antigens and direct immune cell interactions. These cells are also highly responsive to certain venoms (such as Hymenoptera envenomations), which cause histamine secretion, cytokine release and an array of pro-inflammatory functional responses. There are gaps in our understanding of the coupling of venom exposure to specific signaling pathways such as activation of calcium channels. In the present study, we performed a current survey of a model mast cell line selected for its pleiotropic responsiveness to multiple pro-inflammatory inputs. As a heterogenous stimulus, Hymenoptera venom activates multiple classes of conductance at the population level but tend to lead to the measurement of only one type of conductance per cell, despite the cell co-expressing multiple channel types. The data show that I_CRAC, I_ARC, and TRPV-like currents are present in the model mast cell populations and respond to venom exposure. We further assessed individual venom components, specifically secretagogues and arachidonic acid, and identified the conductances associated with these stimuli in mast cells. Single-cell calcium assays and immunofluorescence analysis show that there is heterogeneity of channel expression across the cell population, but this heterogeneity does not explain the apparent selectivity for specific channels in response to exposure to venom as a composite stimulus.

P1409Effectiveness of atrial fibrillation ablation using a contact force stability module with contact force or non-contact force catheter

Funding Acknowledgements

This study was funded by Biosense Webster, Inc.

Background

Catheter ablation is a mainstream treatment option for atrial fibrillation (AF). Recently, contact force (CF) enabled ablation catheters and a stability module were developed to allow for real-time CF sensing and improvement of catheter-tissue stability, which is important for achieving an optimal clinical outcome.  We assessed the relative effectiveness of these new technologies, as well as the optimal CF stability parameters, in a real-world setting.

Purpose

To compare the clinical effectiveness of AF ablations performed with a CF catheter using location stability settings of 2.5 mm maximum distance for 12 s minimum (2.5/12) vs. a non-CF catheter with settings of 3 mm for 7 s (3/7).

Methods

Within 1/14–4/18, 176 de novo AF ablations using either a CF catheter with stability settings of 2.5/12 (n = 92, 5/16–4/18) or a non-CF catheter with stability settings of 3/7 (n = 84, 1/14–3/14) were performed by a single operator at a Canadian medical center. Patients routinely wore 48 hour Holter monitors every three months through the first year. The primary measures of effectiveness were Kaplan-Meier (KM) survival estimates of freedom from AF/atrial tachycardia (AT)/atrial flutter (AFL) recurrence after a 3-month blanking period and reablation.

Results

The CF group was 62.9 ± 10.0 years old, 57.6% male, and 66.3% paroxysmal (PAF). The non-CF group was 61.6 ± 9.9 years old, 63.1% male, and 76.2% PAF. Procedural complications consisted of a single vascular access complication in the non-CF group. The 12-month estimate of freedom from AF/AT/AFL recurrence was 79.4% in the CF group vs. 64.8% in the non-CF group (p = 0.058 for difference in survival over time). 12-month freedom from reablation was 90.4% in the CF group vs. 70.5% in the non-CF group (p = 0.002).

Conclusion

CF ablation with more stringent stability settings of 2.5/12 was more effective than non-CF ablation with stability settings of 3/7, likely attributable to the CF catheter enabling visualization of catheter-tissue contact and the stability module facilitating maintenance of CF stability during ablation.

Abstract Figure.

Myrcene and terpene regulation of TRPV1

Nociceptive Transient Receptor Potential channels such as TRPV1 are targets for treating pain. Both antagonism and agonism of TRP channels can promote analgesia, through inactivation and chronic desensitization. Since plant-derived mixtures of cannabinoids and the Cannabis component myrcene have been suggested as pain therapeutics, we screened terpenes found in Cannabis for activity at TRPV1. We used inducible expression of TRPV1 to examine TRPV1-dependency of terpene-induced calcium flux responses. Terpenes contribute differentially to calcium fluxes via TRPV1 induced by Cannabis-mimetic cannabinoid/terpenoid mixtures. Myrcene dominates the TRPV1-mediated calcium responses seen with terpenoid mixtures. Myrcene-induced calcium influx is inhibited by the TRPV1 inhibitor capsazepine and Myrcene elicits TRPV1 currents in the whole-cell patch-clamp configuration. TRPV1 currents are highly sensitive to internal calcium. When Myrcene currents are evoked, they are distinct from capsaicin responses on the basis of Imax and their lack of shift to a pore-dilated state. Myrcene pre-application and residency at TRPV1 appears to negatively impact subsequent responses to TRPV1 ligands such as Cannabidiol, indicating allosteric modulation and possible competition by Myrcene. Molecular docking studies suggest a non-covalent interaction site for Myrcene in TRPV1 and identifies key residues that form partially overlapping Myrcene and Cannabidiol binding sites. We identify several non-Cannabis plant-derived sources of Myrcene and other compounds targeting nociceptive TRPs using a data mining approach focused on analgesics suggested by non-Western Traditional Medical Systems. These data establish TRPV1 as a target of Myrcene and suggest the therapeutic potential of analgesic formulations containing Myrcene.

Diverse TRPV1 responses to cannabinoids

Cannabinoid compounds are potential analgesics. Users of medicinal Cannabis report efficacy for pain control, clinical studies show that cannabis can be effective and opioid sparing in chronic pain, and some constituent cannabinoids have been shown to target nociceptive ion channels. Here, we explore and compare a suite of cannabinoids for their impact upon the physiology of TRPV1. The cannabinoids tested evoke differential responses in terms of kinetics of activation and inactivation. Cannabinoid activation of TRPV1 displays significant dependence on internal and external calcium levels. Cannabinoid activation of TRPV1 does not appear to induce the highly permeant, pore-dilated channel state seen with Capsaicin, even at high current amplitudes. Finally, we analyzed cannabinoid responses at nociceptive channels other than TRPV1 (TRPV2, TRPM8, and TRPA1), and report that cannabinoids differentially activate these channels. On the basis of response activation and kinetics, state-selectivity and receptor selectivity, it may be possible to rationally design approaches to pain using single or multiple cannabinoids.

Calcium-dependent, non-apoptotic, large plasma membrane bleb formation in physiologically stimulated mast cells and basophils

Large membrane derangements in the form of non-detaching blebs or membrane protrusions occur in a variety of cell stress and physiological situations and do not always reflect apoptotic processes. They have been studied in model mast cells under conditions of cell stress, but their potential physiological relevance to mast cell function and formation in primary mast cells or basophils have not been addressed. In the current study, we examine the large, non-detaching, non-apoptotic, membrane structures that form in model and primary mast cells under conditions of stimulation that are relevant to allergy, atopy and Type IV delayed hypersensitivity reactions. We characterized the inflation kinetics, dependency of formation upon external free calcium and striking geometric consistency of formation for large plasma membrane blebs (LPMBs). We describe that immunologically stimulated LPMBs in mast cells are constrained to form in locations where dissociation of the membrane-associated cytoskeleton occurs. Mast cell LPMBs decorate with wheat germ agglutinin, suggesting that they contain plasma membrane (PM) lectins. Electrophysiological capacitance measurements support a model where LPMBs are not being formed from internal membranes newly fused into the PM, but rather arise from stretching of the existing membrane, or inflation and smoothing of a micro-ruffled PM. This study provides new insights into the physiological manifestations of LPMB in response to immunologically relevant stimuli and in the absence of cell stress, death or apoptotic pathways.

Long-term impact of the low-FODMAP diet on gastrointestinal symptoms, dietary intake, patient acceptability, and healthcare utilization in irritable bowel syndrome

BACKGROUND

The low-FODMAP diet is a frequently used treatment for irritable bowel syndrome (IBS). Most research has focused on short-term FODMAP restriction; however, guidelines recommend that high-FODMAP foods are reintroduced to individual tolerance. This study aimed to assess the long-term effectiveness of the low-FODMAP diet following FODMAP reintroduction in IBS patients.

METHODS

Patients with IBS were prospectively recruited to a questionnaire study following completion of dietitian-led low-FODMAP education. At baseline and following FODMAP restriction (short term) only, gastrointestinal symptoms were measured as part of routine clinical care. Following FODMAP reintroduction, (long term), symptoms, dietary intake, acceptability, food-related quality of life (QOL), and healthcare utilization were assessed. Data were reported for patients who continued long-term FODMAP restriction (adapted FODMAP) and/or returned to a habitual diet (habitual).

KEY RESULTS

Of 103 patients, satisfactory relief of symptoms was reported in 12% at baseline, 61% at short-term follow-up, and 57% at long-term follow-up. At long-term follow-up, 84 (82%) patients continued an 'adapted FODMAP' diet (total FODMAP intake mean 20.6, SD 14.9 g/d) compared with 19 (18%) of patients following a 'habitual' diet (29.4, SD 22.9 g/d, P=.039). Nutritional adequacy was not compromised for either group. The 'adapted FODMAP' group reported the diet cost significantly more than the 'habitual' group (P<.001) and affected social eating (P<.01) but there was no effect on food-related QOL. Healthcare utilization was similar between both groups.

CONCLUSION AND INFERENCES

Low-FODMAP education is effective for long-term IBS management, enables a nutritionally adequate diet, and is broadly acceptable to patients.

Healthcare workers' knowledge and perceptions of the risks associated with emerging extensively drug-resistant bacteria

OBJECTIVE

Guidelines have been issued in 2010 to prevent the spread of emerging extensively resistant bacteria (eXDR), but their implementation is difficult. We aimed to evaluate healthcare workers' (HCW) knowledge and their risk perception to identify barriers to the implementation of guidelines.

METHODS

Semi-structured interviews were conducted at a University Hospital, where case patients are regularly admitted. The interviews focused on HCW's knowledge, risk perception, and challenges met. The evaluation of HCW's knowledge and contagiousness and perception of severity of eXDR carriage were analyzed statistically. Risk perception and opinion about guidelines were analyzed by qualitative description.

RESULTS

One hundred and twenty-one HCWs were interviewed. The category of HCW, having searched for information on resistant bacteria, and having taken care of case patients were associated with better knowledge. The HCW category, age, type of unit, seniority, and having taken care of case patients were associated with risk perceptions. Qualitative analysis identified 61 themes. HCWs were extremely concerned by the spread of bacteria within the hospital. The main challenges identified were organizational and communication issues.

CONCLUSION

HCWs reported a lack of knowledge and a lack of resources to implement guidelines. Strategies to improve guidelines implementation must be based on a better availability of resources, better communication, and new educational methods.

Retrospective evaluation of low long-term efficacy of antiepileptic drugs and ketogenic diet in 39 patients with CDKL5-related epilepsy

OBJECTIVE

Mutations in the CDKL5 gene cause an early-onset epileptic encephalopathy. To date, little is known about effective antiepileptic treatment in this disorder.

METHOD

Accordingly, the aim of this retrospective study was to explore the role of different antiepileptic drugs (AEDs) and the ketogenic diet (KD) in the treatment of this rare genetic disorder. We evaluated the efficacy in 39 patients with CDKL5 mutations at 3, 6 and 12 months after the introduction of each treatment. One patient was lost to follow-up after 6 and 12 months.

RESULTS

The responder rate (>50% reduction in seizure frequency) to at least one AED or KD was 69% (27/39) after 3 months, 45% (17/38) after 6 months and 24% (9/38) after 12 months. The highest rate of seizure reduction after 3 months was reported for FBM (3/3), VGB (8/25), CLB (4/17), VPA (7/34), steroids (5/26), LTG (5/23) and ZNS (2/11). Twelve patients (31%) experienced a seizure aggravation to at least one AED. Most patients showed some but only initial response to various AEDs with different modes of actions.

SIGNIFICANCE

Considering both age-related and spontaneous fluctuation in seizure frequency and the unknown impact of many AEDs or KD on cognition, our data may help defining realistic treatment goals and avoiding overtreatment in patients with CDKL5 mutations. There is a strong need to develop new treatment strategies for patients with this rare mutation.

Circulating Elastin Fragments Are Not Affected by Hepatic, Renal and Hemodynamic Changes, But Reflect Survival in Cirrhosis with TIPS

BACKGROUND AND AIMS

Progressive fibrosis increases hepatic resistance and causes portal hypertension with complications. During progressive fibrosis remodeling and deposition of collagens and elastin occur. Elastin remodeling is crucially involved in fibrosis progression in animal models and human data. This study investigated the association of circulating elastin with the clinical outcome in cirrhotic patients with severe portal hypertension receiving transjugular intrahepatic porto-systemic shunt (TIPS).

METHODS

We analyzed portal and hepatic venous samples of 110 cirrhotic patients obtained at TIPS insertion and 2 weeks later. The circulating levels of elastin fragments (ELM) were determined using specific monoclonal ELISA. The relationship of ELM with clinical short-time follow-up and long-term outcome was investigated.

RESULTS

Circulating levels of ELM showed a gradient across the liver before TIPS with higher levels in the hepatic vein. Interestingly, the circulating ELM levels remained unchanged after TIPS. The circulating levels of ELM in portal and hepatic veins correlated with platelet counts and inversely with serum sodium. Hepatic venous levels of ELM were higher in CHILD C compared to CHILD A and B and were associated with the presence of ascites. Patients with high levels of ELM in the hepatic veins before TIPS showed poorer survival. In multivariate analysis ELM levels in the hepatic veins and MELD were independent predictors of mortality in these patients.

CONCLUSION

This study demonstrated that circulating levels of ELM are not associated with hemodynamic changes, but might reflect fibrosis remodeling and predict survival in patients with severe portal hypertension receiving TIPS independently of MELD.

Conversion from twice-daily to once-daily tacrolimus in simultaneous pancreas-kidney transplant patients

BACKGROUND

Data on the effectiveness of once-daily tacrolimus (Tac-QD) in simultaneous pancreas-kidney (SPK) transplant patients are limited, which is of particular concern because diabetic gastroparesis may affect absorption. The aim of this study was to evaluate the clinical impact of converting SPK patients from twice-daily (Tac-BD) to Tac-QD.

METHODS

From November 2008 to August 2011, 27 SPK recipients (out of 130) were converted from Tac-BD to Tac-QD. Demographics, prescribed doses, trough levels, and creatinine, glucose, and HbA1c values were collected prospectively at the time of conversion and at 1, 2, 3, 6, and 12 months after conversion.

RESULTS

The mean time from transplantation to conversion was 35.81 ± 27.31 months, with 20 patients (74.07%) converted to Tac-QD >12 months after transplantation. There were no significant differences in the tacrolimus dose and trough levels before and after conversion and at all points during the follow-up. Creatinine, glucos,e and HbA1c levels remained stable throughout. Eight patients (29.63%) with gastroparesis had clinical outcomes, drug doses, and trough levels similar to all other patients.

CONCLUSIONS

Stable SPK recipients can safely be converted from Tac-BD to Tac-QD, with no clinical impact on the transplant function. Gastroparesis does not appear to influence tacrolimus dose requirements or trough levels.

Middle East respiratory syndrome coronavirus (MERS-CoV) infections in two returning travellers in the Netherlands, May 2014

Two patients, returning to the Netherlands from pilgrimage in Medina and Mecca, Kingdom of Saudi Arabia, were diagnosed with Middle East respiratory syndrome coronavirus (MERS-CoV) infection in May 2014. The source and mode of transmission have not yet been determined. Hospital-acquired infection and community-acquired infection are both possible.

Outbreak of NDM-1-producing Acinetobacter baumannii in France, January to May 2013

We report the first outbreak of carbapenem-resistant NDM-1-producing Acinetobacter baumannii in Europe, in a French intensive-care unit in January to May 2013. The index patient was transferred from Algeria and led to the infection/colonisation of five additional patients. Concurrently, another imported case from Algeria was identified. The seven isolates were genetically indistinguishable, belonging to ST85. The bla(NDM-1) carbapenemase gene was part of the chromosomally located composite transposon Tn125. This report underscores the growing concern about the spread of NDM-1-producing A. baumannii in Europe.

Analyses of multiple-site and concurrent Chlamydia trachomatis serovar infections, and serovar tissue tropism for urogenital versus rectal specimens in male and female patients

OBJECTIVES

The aims of this study were: to determine the incidence of concurrent infections on a serovar level; to determine the incidence of multiple anatomical infected sites on a detection and genotyping level and analyse site-specific serovar distribution; to identify tissue tropism in urogenital versus rectal specimens.

METHODS

Chlamydia trachomatis-infected patients in two populations were analysed: 75 visiting the outpatient department of obstetrics and gynaecology of the MC Haaglanden, and 358 visiting the outpatient sexually transmitted disease clinic, The Hague, The Netherlands. The PACE 2 assay (Gen-Probe) was used to detect C trachomatis from urethral, cervical, vaginal, oropharyngeal and anorectal swabs. C trachomatis genotyping was performed on all C trachomatis positive samples, using the CT-DT genotyping assay.

RESULTS

Samples from 433 patients (256 female and 177 male) with confirmed C trachomatis infection were analysed. In 11 patients (2.6%), concurrent serovars in one anatomical sample site were present. In 62 (34.1%) female and four (9.3%) male patients, multiple sample site infections were found. A substantial percentage of women tested at the cervical/vaginal and rectal site were found to be positive at both sites (36.1%, 22/61). In men, D/Da and G/Ga serovars were more prevalent in rectal than urogenital specimens (p=0.0081 and p=0.0033, respectively), while serovar E was more prevalent in urogenital specimens (p=0.0012).

CONCLUSIONS

The prevalence of multiple serovar infections is relatively low. Significant differences in serovar distribution are found in rectal specimens from men, with serovar G/Ga being the most prominent, suggesting tissue tropism.

The first case of protease-sensitive prionopathy (PSPr) in The Netherlands: a patient with an unusual GSS-like clinical phenotype

An atypical case of prion disease is described in a 54-year-old Dutch man, homozygous for valine at codon 129 of the prion protein gene (PRNP). The clinical phenotype was characterised by progressive dementia, spastic paraplegia and sensorimotor polyneuropathy. The disease duration was 20 months. Genetic analysis of PRNP did not reveal any abnormalities. Neuropathologically, only mild spongiform change and a coarse granular immunohistochemical staining for the abnormal prion protein, PrP(Sc), was observed, with poorly formed plaques in the molecular layer of the cerebellar cortex. However, Western blotting showed low but detectable levels of proteinase K(PK)-resistant PrP(Sc) occurring in an unusual ladder-like profile. These features define a phenotype that corresponds to the recently described protease-sensitive prionopathy (PSPr). Our report on the first Dutch patient with PSPr further expands the spectrum of prionopathies and exemplifies the need to re-evaluate cases of atypical prion disease.

Registering preprocedure volumetric images with intraprocedure 3-D ultrasound using an ultrasound imaging model

For many image-guided interventions there exists a need to compute the registration between preprocedure image(s) and the physical space of the intervention. Real-time intraprocedure imaging such as ultrasound (US) can be used to image the region of interest directly and provide valuable anatomical information for computing this registration. Unfortunately, real-time US images often have poor signal-to-noise ratio and suffer from imaging artefacts. Therefore, registration using US images can be challenging and significant preprocessing is often required to make the registrations robust. In this paper we present a novel technique for computing the image-to-physical registration for minimally invasive cardiac interventions using 3-D US. Our technique uses knowledge of the physics of the US imaging process to reduce the amount of preprocessing required on the 3-D US images. To account for the fact that clinical US images normally undergo significant image processing before being exported from the US machine our optimization scheme allows the parameters of the US imaging model to vary. We validated our technique by computing rigid registrations for 12 cardiac US/magnetic resonance imaging (MRI) datasets acquired from six volunteers and two patients. The technique had mean registration errors of 2.1-4.4 mm, and 75% capture ranges of 5-30 mm. We also demonstrate how the same approach can be used for respiratory motion correction: on 15 datasets acquired from five volunteers the registration errors due to respiratory motion were reduced by 45%-92%.

Inherited Creutzfeldt-Jakob disease in a Dutch patient with a novel five octapeptide repeat insertion and unusual cerebellar morphology

An atypical case of inherited Creutzfeldt-Jakob disease (CJD) is described in a 35-year-old Dutch woman, homozygous for methionine at codon 129 of the prion protein gene (PRNP). The clinical phenotype was characterised by slowly progressive cognitive decline and parkinsonism. Neuropathological findings consisted of scanty spongiosis and only faint to absent immunohistochemical staining for the abnormal prion protein, PrP(Sc), with patchy deposits in the cerebellar cortex. Purkinje cells were abnormally located in the molecular layer of the cerebellum. Western blot analysis showed the co-occurrence of PrP(Sc) types 1 and 2 with an unusual distribution. Sequence analysis disclosed a novel 120 bp insertion in the octapeptide repeat region of the PRNP, encoding five additional R2 octapeptide repeats. These features define an unusual neuropathological phenotype and novel genotype, further expanding the spectrum of genotype-phenotype correlations in inherited prion diseases and emphasising the need to carry out pre-mortem PRNP sequencing in all young patients with atypical dementias.

Panencephalopathic Creutzfeldt-Jakob disease in the Netherlands and the UK: clinical and pathological characteristics of nine patients

AIMS

The panencephalopathic type of Creutzfeldt-Jakob disease (PECJD) has extensive abnormalities in cerebral white matter as well as the cortex. PECJD has rarely been described in Caucasians and debate continues on its classification and pathogenesis. We describe our experience of PECJD over a 14-year period of surveillance for CJD in the Netherlands and the UK.

METHODS

Between 1993 and 2006, nine cases of PECJD were identified. Clinical, histological and biochemical characteristics of all patients were analysed and compared; all cases were classified clinically as sporadic CJD.

RESULTS

The median age at onset was 57.8 years and median disease duration was 22 months. The average brain weight was 887 g. Most patients showed a two-stage clinical course with initial rapid deterioration to a state of akinetic mutism, which then persisted over a longer time scale. Neuropathological findings were characterized by severe global atrophy with status spongiosus. Cerebral white matter involvement tended to be associated with either disease duration or severity of cerebral cortical lesions. Five patients could be classified into the MM1 subtype of sporadic CJD, one patient into the MM2 subgroup and another into the MV2 subgroup. Two patients were heterozygous at codon 129 in the prion protein gene and contained both type 1 and type 2 PrP(res) isoforms in the brain.

CONCLUSIONS

We believe that white matter pathology in PECJD represents an end-stage pattern that reflects secondary degeneration due to widespread cortical neuronal loss that occurs in the early part of the disease, rather than representing a primary lesion.

Structural basis for pH-dependent alterations of reaction specificity of vertebrate lipoxygenase isoforms

Lipoxygenases have been classified according to their specificity of fatty acid oxygenation and for several plant enzymes pH-dependent alterations in the product patterns have been reported. Assuming that the biological role of mammalian lipoxygenases is based on the formation of specific reaction products, pH-dependent alterations would impact enzymes' functionality. In this study we systematically investigated the pH-dependence of vertebrate lipoxygenases and observed a remarkable stability of the product pattern in the near physiological range for the wild-type enzyme species. Site-directed mutagenesis of selected amino acids and alterations in the substrate concentrations induced a more pronounced pH-dependence of the reaction specificity. For instance, for the V603H mutant of the human 15-lipoxygenase-2 8-lipoxygenation was dominant at acidic pH (65%) whereas 15-H(p)ETE was the major oxygenation product at pH 8. Similarly, the product pattern of the wild-type mouse 8-lipoxygenase was hardly altered in the near physiological pH range but H604F exchange induced strong pH-dependent alterations in the positional specificity. Taken together, our data suggest that the reaction specificities of wild-type vertebrate lipoxygenase isoforms are largely resistant towards pH alterations. However, we found that changes in the assay conditions (low substrate concentration) and introduction/removal of a critical histidine at the active site impact the pH-dependence of reaction specificity for some lipoxygenase isoforms.