Hospital-based antimicrobial stewardship in Denmark, Greenland and the Faroe Islands - current landscape and barriers.

OBJECTIVES: To describe the current organization and implementation of formalized, multi-disciplinary hospital-based antimicrobial stewardship (AMS) structures in Denmark, the Faroe Islands and Greenland. METHODS: A structured electronic questionnaire was sent to all trainees and specialists in clinical microbiology (N=207) and infectious diseases (N=260), as well as clinical pharmacists (N=20) and paediatricians (N=10) with expertise in infectious diseases. The survey had 30 multiple-choice, rating-scale, and open-ended questions based on an international consensus checklist for hospital AMS, adapted to a Danish context. RESULTS: Overall, 145 individual responses representing 20 hospitals were received. Nine hospitals (45%) reported a formal AMS strategy, eight (40%) a formal organizational multi-disciplinary structure and a multi-disciplinary AMS team, and six (30%) a designated professional as a leader of the AMS team. A majority of hospitals reported access to updated guidelines (80%) and regularly monitored and reported the quantity of antibiotics prescribed (70% and 65%, respectively). Only one hospital (5%) reported a dedicated, sustainable and sufficient AMS budget, three hospitals (15%) audited courses of therapy for specific agents/clinical conditions and four hospitals (20%) had a document clearly defining roles, procedures of collaboration and responsibilities for AMS. A total of 42% of all individual respondents had received formal AMS training. Main barriers were a lack of financial resources (52%), a lack of mandate from the hospital management (30%) and AMS not being a priority (18%). CONCLUSIONS: Core elements important for multi-disciplinary hospital-based AMS can be strengthened in Danish hospitals. Funding, clear mandates, prioritization from the hospital management and the implementation of multi-disciplinary AMS structures may help close the identified gaps.

Monocyte secretory profiling in a clinical and MEFV genotype-characterized cohort of Danish familial Mediterranean fever patients: diagnostic potential of CCL1 and CXCL1.

OBJECTIVE: The autoinflammatory disease familial Mediterranean fever (FMF), characterized by recurrent attacks of sterile fever, serosal, and/or synovial inflammation, is caused by variants in the Mediterranean fever gene, MEFV, coding for the pyrin inflammasome sensor. The diagnosis of FMF is mainly based on clinical symptoms and confirmed by detection of disease-associated MEFV variants. However, the diagnosis is challenging among patients carrying variants of uncertain clinical significance (VUS). In this study, we aimed to identify potential FMF discriminatory diagnostic markers in a cohort of clinically characterized FMF patients. METHOD: We established a cohort of clinically and MEFV genotype-characterized FMF patients by enrolling patients from major Danish hospitals (n = 91). The secretory profile of pyrin inflammasome-activated monocytes from healthy donors (HDs) and MEFV-characterized FMF patients (n = 28) was assessed by analysing cell supernatants for a custom-designed panel of 23 cytokines, chemokines, and soluble tumour necrosis factor receptors associated with monocyte and macrophage function. RESULTS: MEFV genotypes in Danish FMF patients were associated with age at symptom onset (p < 0.05), FMF among relatives (p < 0.01), proportion of patients in colchicine treatment (p < 0.01), and treatment response (p < 0.05). Secretion of chemokines CCL1 and CXCL1 from pyrin-activated FMF monocytes was significantly decreased compared to HDs (p < 0.05), and could discriminate FMF patients with 'non-confirmatory' MEFV genotypes from HDs with 80.0% and 70.0% sensitivity for CCL1 and CXCL1, respectively (p < 0.05). CONCLUSION: Our data suggest that a functional diagnostic assay based on CCL1 or CXCL1 levels in pyrin-activated patient monocytes may contribute to FMF diagnosis in patients with VUS.

Non-invasive sampling of water-borne hormones demonstrates individual consistency of the cortisol response to stress in laboratory zebrafish (Danio rerio).

Glucocorticoid (GC) stress hormones are well-known for their impact on phenotypic traits ranging from immune function to behaviour and cognition. For that reason, consistent aspects of an individual's physiological stress response (i.e. GC responsiveness) can predict major elements of life-history trajectory. Zebrafish (Danio rerio) emerge as a promising model to study such consistent trait correlations, including the development of individual stress coping styles, i.e. consistent associations between physiological and behavioral traits. However, consistency in GC responsiveness of this popular animal model remains to be confirmed. Such a study has so far been hampered by the small-bodied nature and insufficient blood volume of this species to provide repeated measurements of circulating GCs. Here, we adopted a technique that allows for repeated, non-invasive sampling of individual zebrafish by quantifying GCs from holding water. Our findings indicate consistency of the magnitude of post-stress GC production over several consecutive stress events in zebrafish. Moreover, water-borne GCs reflect individual variation in GC responsiveness with the strongest consistency seen in males.

Characteristics of patients with familial Mediterranean fever in Denmark: a retrospective nationwide register-based cohort study.

Objectives: To investigate epidemiology, demography, and genetic and clinical characteristics of patients with familial Mediterranean fever (FMF) in Denmark. Method: In this population-based, cross-sectional cohort study, we identified FMF patients from discharge diagnoses using ICD-10 codes in the Danish National Patient Register, and linked data from the Danish Civil Registration System and laboratory databases for results of MEFV gene variant screening. Results: We identified 495 FMF patients (prevalence 1:11 680) with a median age of 29 years and a female ratio of 51%. The median age at diagnosis of FMF was 13 (IQR 7-22) years, with an estimated median diagnostic delay of 3 (IQR 0.7-6.9) years. The predominant ethnicities were Turkish (41.8%), Lebanese (15.8%), Syrian (6.5%), South-West Asian (7.9%), and South-East Asian (3.0%). The MEFV genotype distribution was 18.7% homozygous, 21.2% compound heterozygous, 32.0% heterozygous, 11.0% with complex alleles or unresolved zygosity, and 17.1% with no detected variants. M694V was the most prevalent variant in the overall cohort (32.5%). Homozygous or compound heterozygous MEFV exon 10 variants were associated with younger age at diagnosis (p < 0.001) and reduced number of hospital contacts before diagnosis (p = 0.008). The Charlson Comorbidity Index was ≥ 2 in 8.1% of patients. The prevalence of amyloidosis was 1.0%. Conclusions: FMF in Denmark is rare and patients are mainly of Eastern Mediterranean ethnicity. Diagnostic delay was long but patients with exon 10 MEFV variants were diagnosed at a younger age. Prolonged diagnostic delay is probably caused by lack of FMF awareness in the Danish healthcare system.

Molecular evidence of sustained urban malaria transmission in Amazonian Brazil, 2014-2015.

The relative contribution of imported vs. locally acquired infections to urban malaria burden remains largely unexplored in Latin America, the most urbanised region in the developing world. Here we use a simple molecular epidemiology framework to examine the transmission dynamics of Plasmodium vivax in Mâncio Lima, the Amazonian municipality with the highest malaria incidence rate in Brazil. We prospectively genotyped 177 P. vivax infections diagnosed in urban residents between June 2014 and July 2015 and showed that local parasites are structured into several lineages of closely related microsatellite haplotypes, with the largest genetic cluster comprising 32% of all infections. These findings are very unlikely under the hypothesis of multiple independent imports of parasite strains from the rural surroundings. Instead, the presence of an endemic near-clonal parasite lineage circulating over 13 consecutive months is consistent with a local P. vivax transmission chain in the town, with major implications for malaria elimination efforts in this and similar urban environments across the Amazon.

Detection of meticillin-resistant Staphylococcus aureus and carbapenemase-producing Enterobacteriaceae in Danish emergency departments - evaluation of national screening guidelines.

BACKGROUND: Multi-resistant bacteria (MRB) are an emerging problem. Early identification of patients colonized with MRB is mandatory to avoid in-hospital transmission and to target antibiotic treatment. Since most patients pass through specialized emergency departments (EDs), these departments are crucial in early identification. The Danish National Board of Health (DNBH) has developed exposure-based targeted screening tools to identify and isolate carriers of meticillin-resistant Staphylococcus aureus (MRSA) and carbapenemase-producing Enterobacteriaceae (CPE). AIM: To assess the national screening tools for detection of MRSA and CPE carriage in a cohort of acute patients. The objectives were to investigate: (i) if the colonized patients were detected; and (ii) if the colonized patients were isolated. METHODS: This was a multi-centre cross-sectional survey of adults visiting EDs. The patients answered the DNBH questions, and swabs were taken from the nose, throat and rectum. The collected samples were examined for MRSA and CPE. Screening performances were calculated. FINDINGS: Of the 5117 included patients, 16 were colonized with MRSA and four were colonized with CPE. The MRSA screening tool had sensitivity of 50% [95% confidence interval (CI) 25-75%] for carrier detection and 25% (95% CI 7-52%) for carrier isolation. The CPE screening tool had sensitivity of 25% (95% CI 1-81%) and none of the CPE carriers were isolated. CONCLUSION: The national screening tools were of limited use as the majority of MRSA and CPE carriers passed unidentified through the EDs, and many patients were isolated unnecessarily.

Risk factors during pregnancy and birth-related complications in HIV-positive versus HIV-negative women in Denmark, 2002-2014.

OBJECTIVES: We aimed to compare risk factors for adverse pregnancy outcomes in women living with HIV (WLWH) with those in women of the general population (WGP) in Denmark. Further, we estimated risk of pregnancy- or birth-related complications. METHODS: A retrospective cohort study including all WLWH who delivered a live-born child from 2002 to 2014 and WGP, matched by origin, age, year and parity, was carried out. We compared risk factors during pregnancy and estimated risk of pregnancy- and birth-related complications using multivariate logistic regression. RESULTS: A total of 2334 pregnancies in 304 WLWH and 1945 WGP were included in the study. WLWH had more risk factors present than WGP during pregnancy: previous caesarean section (CS) (24.7% versus 16.3%, respectively; P = 0.0001), smoking (14.2% versus 7.5%, respectively; P = 0.0001) and previous perinatal/neonatal death (2.3% versus 0.9%, respectively; P = 0.03). We found no difference between groups regarding gestational diabetes, hypertensive disorders, low birth weights or premature delivery. More children of WLWH had intrauterine growth retardation (IUGR) [adjusted odds ratio (aOR) 1.9; 95% confidence interval (CI) 1.1-3.2; P = 0.02]. Median gestational age and birth weight were lower in children born to WLWH. WLWH had a higher risk of emergency CS (EmCS) (aOR 1.6; 95% CI 1.2-2.1; P = 0.0005) and postpartum haemorrhage (aOR 1.4; 95% CI 1.0-1.9; P = 0.02) but not infection, amniotomy, failure to progress, low activity-pulse-grimace-appearance-respiration (APGAR) score or signs of asphyxia. CONCLUSIONS: WLWH had more risk factors present during pregnancy, similar risks of most pregnancy- and birth-related complications but a higher risk of postpartum haemorrhage and EmCS compared with WGP. Children born to WLWH had lower median birth weights and gestational ages and were at higher risk of IUGR.

Contrasting associations between breeding coloration and parasitism of male Arctic charr relate to parasite species and life cycle stage.

Conspicuous carotenoid ornamentation is considered a signal of individual "quality" and one of the most intensely studied traits found to co-vary with parasitism. Since it has been suggested that only "high quality" individuals have enough resources to express excessive sexual ornaments and resist parasites, current theory struggles to explain cases where the brightest individuals carry the most parasites. Surprisingly little emphasis has been put on the contrasting routes to fitness utilized by different parasite species inhabiting the same host. Using Arctic charr (Salvelinus alpinus) as model species, we hypothesized that skin redness and allocation of carotenoids between skin and muscle (redness ratio) will be positively and negatively associated with parasites using the fish as an intermediate and final host, respectively. Both pigment parameters were indeed positively associated with abundances of parasites awaiting trophic transmission (Diplostomum sp. and Diphyllobothrium spp.) and negatively associated with the abundance of adult Eubothrium salvelini tapeworms. These empirical data demonstrate that contrasting associations between carotenoid coloration and parasite intensities relates to the specific premises of different parasite species and life cycle stages.

Primary health care: an opportunity for early identification of people living with undiagnosed HIV infection.

OBJECTIVES: We aimed to determine the fraction of HIV-diagnosed individuals who had primary health care (PHC) contacts 3 years prior to HIV diagnosis and whether the risk of HIV diagnosis and degree of immunodeficiency were associated with the frequency of visits or procedures performed. METHODS: We used data from national registries to conduct a population-based nested case-control study. Cases were individuals diagnosed with HIV infection in Denmark from 1998 to 2016. Population controls were extracted from the general population matched 13:1 on gender and age. We used conditional logistic regression. As there was a statistically significant interaction, analyses were further stratified by gender and Danish/non-Danish origin. RESULTS: We identified 2784 cases and 36 192 controls. Ninety-three per cent of cases and 88% of controls attended PHC at least once in the 3 years prior to diagnosis, with a higher median number of visits to PHC (NVPC) for cases. We found a statistically significant positive association between NVPC and risk of subsequent HIV diagnosis in men and non-Danish women. A U-shaped association between NVPC and risk of HIV diagnosis among Danish women. No substantial association between NVPC and degree of immunodeficiency was found. Risk of HIV diagnosis and degree of immunodeficiency were weakly associated with type of procedures performed. CONCLUSIONS: For most HIV-infected individuals, there seem to be many opportunities for earlier diagnosis in PHC. In men and non-Danish women, the risk of HIV diagnosis but not the degree of immunodeficiency was related to NVPC. The results suggest that the type of medical procedure performed cannot not be used as a guide by the primary physician to indicate which patients to test.

Assessment of mode of delivery and predictors of emergency caesarean section among women living with HIV in a matched-pair setting with women from the general population in Denmark, 2002-2014.

OBJECTIVES: We aimed to assess mode of delivery and predictors of emergency caesarean section (EmCS) in women living with HIV (WLWH) in a matched-pair setting with women from the general population (WGP) in Denmark. Further, we analysed birth plan in WLWH. METHODS: All WLWH giving birth to live-born children from 2002 to 2014 were included in the study. Data were retrieved from medical records and national registries. WLWH were matched 1:5 by age, birth year, parity and ethnicity to WGP. Multivariate logistic regression was used to estimate predictors. RESULTS: We included 389 WLWH and 1945 WGP in the study. At delivery, all WLWH were on antiretroviral therapy and 85.6% had HIV RNA <40 HIV-1 RNA copies/mL. Mean age was 32.7 years [95% confidence interval (CI) 32.1-33.2 years]. Mode of delivery differed significantly between WLWH and WGP [vaginal delivery, 33.4% versus 73.3%, respectively; elective caesarean section (ECS), 40.6% versus 9.7%, respectively; EmCS, 26% versus 17%, respectively; P < 0.0001]. Age > 40 years [adjusted odds ratio (aOR) 2.3; 95% CI 1.5-3.5], asphyxia (aOR 3.2; 95% CI 2.4-4.1), delivery during the evening and at night [aOR 2.3 (95% CI 1.7-3.0) and aOR 2.0 (95% CI 1.5-2.7), respectively], preterm delivery (aOR 3.8; 95% CI 2.6-5.6) and premature rupture of membranes (aOR 3.0; 95% CI 2.1-4.4) predicted EmCS. WLWH had a higher risk of EmCS compared with WGP [2002-2006, aOR 2.0 (95% CI 1.2-3.3); 2007-2008, aOR 2.9 (95% CI 1.4-5.9); 2009-2014, aOR 2.6 (95% CI 1.7-3.9)]. After 2007, more than half of WLWH planned to deliver vaginally. Prior caesarean section was associated with ECS (aOR 11.0; 95% CI 4.5-26.8). No mother-to-child transmission occurred. CONCLUSIONS: Increasing numbers of WLWH deliver vaginally. Despite virological suppression, more WLWH plan and deliver by ECS than WGP. WLWH had a twofold higher risk of EmCS compared with WGP.

Managing atypical and typical herpetic central nervous system infections: results of a multinational study.

There have been many studies pertaining to the management of herpetic meningoencephalitis (HME), but the majority of them have focussed on virologically unconfirmed cases or included only small sample sizes. We have conducted a multicentre study aimed at providing management strategies for HME. Overall, 501 adult patients with PCR-proven HME were included retrospectively from 35 referral centres in 10 countries; 496 patients were found to be eligible for the analysis. Cerebrospinal fluid (CSF) analysis using a PCR assay yielded herpes simplex virus (HSV)-1 DNA in 351 patients (70.8%), HSV-2 DNA in 83 patients (16.7%) and undefined HSV DNA type in 62 patients (12.5%). A total of 379 patients (76.4%) had at least one of the specified characteristics of encephalitis, and we placed these patients into the encephalitis presentation group. The remaining 117 patients (23.6%) had none of these findings, and these patients were placed in the nonencephalitis presentation group. Abnormalities suggestive of encephalitis were detected in magnetic resonance imaging (MRI) in 83.9% of the patients and in electroencephalography (EEG) in 91.0% of patients in the encephalitis presentation group. In the nonencephalitis presentation group, MRI and EEG data were suggestive of encephalitis in 33.3 and 61.9% of patients, respectively. However, the concomitant use of MRI and EEG indicated encephalitis in 96.3 and 87.5% of the cases with and without encephalitic clinical presentation, respectively. Considering the subtle nature of HME, CSF HSV PCR, EEG and MRI data should be collected for all patients with a central nervous system infection.

Factors associated with disallowance of compulsory mental healthcare referrals.

OBJECTIVE: Norwegian studies report that a substantial amount of referrals for compulsory mental health care are disallowed at specialist assessment, at a rate that varies with referring agent. Knowledge on factors associated with disallowance could improve the practice of compulsory mental health care. This study aims to examine such factors, placing particular emphasis on the impact of referring agents. METHOD: This study utilized data from the prospective, longitudinal cohort study 'Suicidality in Psychiatric Emergency Admissions' conducted at a Norwegian psychiatric emergency unit which served approximately 400 000 inhabitants. Data on referral, admission and patient characteristics were retrieved on compulsory admissions conducted between 1 May 2005 and 30 April 2008. Bivariate and logistic regression analyses and structural multilevel modelling were performed. RESULTS: Among 2813 compulsory admissions, 764 were disallowed. Low competence in the referring agent, high GAF S score, observed alcohol or drug intoxication, reported suicide risk, and the presence of neurotic, stress-related and somatoform disorders, personality disorders and other non-specified diagnoses were associated with above average disallowance frequency. Non-Norwegian ethnicity and schizophrenia spectrum disorders were associated with below average disallowance rates. CONCLUSION: Among several factors associated with disallowance, low symptom load was the strongest, whilst referring agent competence modestly affected disallowance rate.

Incidence of cervical dysplasia and cervical cancer in women living with HIV in Denmark: comparison with the general population.

OBJECTIVES: Women living with HIV (WLWH) are reportedly at increased risk of invasive cervical cancer (ICC). A recent publication found that WLWH in Denmark attend the national ICC screening programme less often than women in the general population. We aimed to estimate the incidence of cervical dysplasia and ICC in WLWH in Denmark compared with that in women in the general population. METHODS: We studied a nationwide cohort of WLWH and a cohort of 15 age-matched women per WLWH from the general population for the period 1999-2010. Pathology samples were obtained from The Danish Pathology Data Bank, which contains nationwide records of all pathology specimens. The cumulative incidence and hazard ratios (HRs) for time from inclusion to first cervical intraepithelial neoplasia (CIN)/ICC and time from first normal cervical cytology result to first CIN/ICC were estimated. Sensitivity analyses were performed to include prior screening outcome, screening intensity and treatment of CIN/ICC in the interpretation of results. RESULTS: We followed 1140 WLWH and 17 046 controls with no prior history of ICC or hysterectomy for 9491 and 156 865 person-years, respectively. Compared with controls, the overall incidences of CIN1 or worse (CIN1+), CIN2+ and CIN3+, but not ICC, were higher in WLWH and predicted by young age and a CD4 count < 200 cells/µL. In women with normal baseline cytology, incidences of CIN1+ and CIN2+ were higher in WLWH. However, when we compared subgroups of WLWH and controls where women in both groups were adherent to the national ICC screening programme and had a normal baseline cytology, incidences of CIN and ICC were comparable. CONCLUSIONS: Overall, WLWH developed more cervical disease than controls. Yet, in WLWH and controls adherent to the national ICC screening programme and with normal baseline cytology, incidences of CIN and ICC were comparable.

Penium margaritaceum as a model organism for cell wall analysis of expanding plant cells.

The growth of a plant cell encompasses a complex set of subcellular components interacting in a highly coordinated fashion. Ultimately, these activities create specific cell wall structural domains that regulate the prime force of expansion, internally generated turgor pressure. The precise organization of the polymeric networks of the cell wall around the protoplast also contributes to the direction of growth, the shape of the cell, and the proper positioning of the cell in a tissue. In essence, plant cell expansion represents the foundation of development. Most studies of plant cell expansion have focused primarily upon late divergent multicellular land plants and specialized cell types (e.g., pollen tubes, root hairs). Here, we describe a unicellular green alga, Penium margaritaceum (Penium), which can serve as a valuable model organism for understanding cell expansion and the underlying mechanics of the cell wall in a single plant cell.

The microbiological diagnosis of tuberculous meningitis: results of Haydarpasa-1 study.

We aimed to provide data on the diagnosis of tuberculous meningitis (TBM) in this largest case series ever reported. The Haydarpasa-1 study involved patients with microbiologically confirmed TBM in Albania, Croatia, Denmark, Egypt, France, Hungary, Iraq, Italy, Macedonia, Romania, Serbia, Slovenia, Syria and Turkey between 2000 and 2012. A positive culture, PCR or Ehrlich-Ziehl-Neelsen staining (EZNs) from the cerebrospinal fluid (CSF) was mandatory for inclusion of meningitis patients. A total of 506 TBM patients were included. The sensitivities of the tests were as follows: interferon-γ release assay (Quantiferon TB gold in tube) 90.2%, automated culture systems (ACS) 81.8%, Löwenstein Jensen medium (L-J) 72.7%, adenosine deaminase (ADA) 29.9% and EZNs 27.3%. CSF-ACS was superior to CSF L-J culture and CSF-PCR (p <0.05 for both). Accordingly, CSF L-J culture was superior to CSF-PCR (p <0.05). Combination of L-J and ACS was superior to using these tests alone (p <0.05). There were poor and inverse agreements between EZNs and L-J culture (κ = -0.189); ACS and L-J culture (κ = -0.172) (p <0.05 for both). Fair and inverse agreement was detected for CSF-ADA and CSF-PCR (κ = -0.299, p <0.05). Diagnostic accuracy of TBM was increased when both ACS and L-J cultures were used together. Non-culture tests contributed to TBM diagnosis to a degree. However, due to the delays in the diagnosis with any of the cultures, combined use of non-culture tests appears to contribute early diagnosis. Hence, the diagnostic approach to TBM should be individualized according to the technical capacities of medical institutions particularly in those with poor resources.

The interplay between P uptake pathways in mycorrhizal peas: a combined physiological and gene-silencing approach.

Arbuscular mycorrhizal fungi (AMF) have a key role in plant phosphate (Pi) uptake by their efficient capture of soil phosphorus (P) that is transferred to the plant via Pi transporters in the root cortical cells. The activity of this mycorrhizal Pi uptake pathway is often associated with downregulation of Pi transporter genes in the direct Pi uptake pathway. As the total Pi taken up by the plant is determined by the combined activity of mycorrhizal and direct pathways, it is important to understand the interplay between these, in particular the actual activity of the pathways. To study this interplay we modulated the delivery of Pi via the mycorrhizal pathway in Pisum sativum by two means: (1) Partial downregulation by virus-induced gene silencing of PsPT4, a putative Pi transporter gene in the mycorrhizal pathway. This resulted in decreased fungal development in roots and soil and led to reduced plant Pi uptake. (2) Changing the percentage of AMF-colonized root length by using non-, half-mycorrhizal or full-mycorrhizal split-root systems. The combination of split roots, use of ³²P and ³³P isotopes and partial silencing of PsPT4 enabled us to show that the expression of PsPT1, a putative Pi transporter gene in the direct pathway, was negatively correlated with increasing mycorrhizal uptake capacity of the plant, both locally and systemically. However, transcript changes in PsPT1 were not translated into corresponding, systemic changes in actual direct Pi uptake. Our results suggest that AMF have a limited long-distance impact on the direct pathway.

Per-unit-living tissue normalization of real-time RT-PCR data in ischemic rat hearts.

In studies of gene expression in acute ischemic heart tissue, internal reference genes need to show stable expression per-unit-living tissue to hinder dead cells from biasing real-time RT-PCR data. Until now, this important issue has not been appropriately investigated. We hypothesized that the expression of seven internal reference genes would show stable per-unit-living tissue expression in Langendorff-perfused rat hearts subjected to ischemia-reperfusion. This was found for cyclophilin A, GAPDH, RPL-32, and PolR2A mRNA, with GAPDH showing the highest degree of stability (R = 0.11), suggesting unchanged rates of mRNA transcription in live cells and complete degradation of mRNA from dead cells. The infarct size-dependent degradation of GAPDH was further supported by a close correlation between changes in GAPDH mRNA and changes in RNA quality measured as RNA integrity number (R = 0.90, P < 0.05). In contrast, ß-actin and 18S rRNA showed stable expression per-unit-weight tissue and a positive correlation with infarct size (R = 0.61 and R = 0.77, P < 0.05 for both analyses). The amount of total RNA extracted per-unit-weight tissue did not differ between groups despite wide variation in infarct size (7.1-50.1%). When ß-actin expression was assessed using four different normalization strategies, GAPDH and geNorm provided appropriate per-unit-living expression, while 18S and total RNA resulted in marked underestimations. In studies of ischemic tissues, we recommend using geometric averaging of carefully selected reference genes for normalization of real-time RT-PCR data. A marked shift in the mRNA/rRNA ratio renders rRNA as useless for normalization purposes.

Myonuclei acquired by overload exercise precede hypertrophy and are not lost on detraining.

Effects of previous strength training can be long-lived, even after prolonged subsequent inactivity, and retraining is facilitated by a previous training episode. Traditionally, such "muscle memory" has been attributed to neural factors in the absence of any identified local memory mechanism in the muscle tissue. We have used in vivo imaging techniques to study live myonuclei belonging to distinct muscle fibers and observe that new myonuclei are added before any major increase in size during overload. The old and newly acquired nuclei are retained during severe atrophy caused by subsequent denervation lasting for a considerable period of the animal's lifespan. The myonuclei seem to be protected from the high apoptotic activity found in inactive muscle tissue. A hypertrophy episode leading to a lasting elevated number of myonuclei retarded disuse atrophy, and the nuclei could serve as a cell biological substrate for such memory. Because the ability to create myonuclei is impaired in the elderly, individuals may benefit from strength training at an early age, and because anabolic steroids facilitate more myonuclei, nuclear permanency may also have implications for exclusion periods after a doping offense.

Melanin-based skin spots reflect stress responsiveness in salmonid fish.

Within animal populations, genetic, epigenetic and environmental factors interact to shape individual neuroendocrine and behavioural profiles, conferring variable vulnerability to stress and disease. It remains debated how alternative behavioural syndromes and stress coping styles evolve and are maintained by natural selection. Here we show that individual variation in stress responsiveness is reflected in the visual appearance of two species of teleost fish; rainbow trout (Oncorhynchus mykiss) and Atlantic salmon (Salmo salar). Salmon and trout skin vary from nearly immaculate to densely spotted, with black spots formed by eumelanin-producing chromatophores. In rainbow trout, selection for divergent hypothalamus-pituitary-interrenal responsiveness has led to a change in dermal pigmentation patterns, with low cortisol-responsive fish being consistently more spotted. In an aquaculture population of Atlantic salmon individuals with more spots showed a reduced physiological and behavioural response to stress. Taken together, these data demonstrate a heritable behavioural-physiological and morphological trait correlation that may be specific to alternative coping styles. This observation may illuminate the evolution of contrasting coping styles and behavioural syndromes, as occurrence of phenotypes in different environments and their response to selective pressures can be precisely and easily recorded.

Virus-induced gene silencing (VIGS) as a reverse genetic tool to study development of symbiotic root nodules.

Virus-induced gene silencing (VIGS) can provide a shortcut to plants with altered expression of specific genes. Here, we report that VIGS of the Nodule inception gene (Nin) can alter the nodulation phenotype and Nin gene expression in Pisum sativum. PsNin was chosen as target because of the distinct non-nodulating phenotype of nin mutants in P. sativum, Lotus japonicus, and Medicago truncatula. The vector based on Pea early browning virus (PEBV) was engineered to carry one of three nonoverlapping fragments (PsNinA, PsNinB, and PsNinC) derived from the PsNin cDNA. Vector inoculation was mediated by agroinfiltration and, 2 weeks later, a Rhizobium leguminosarum bv. viceae culture was added in order to induce root nodulation. At this time point, it was estimated that systemic silencing was established because leaves of reference plants inoculated with PEBV carrying a fragment of Phytoene desaturase displayed photo bleaching. Three weeks after Rhizobium spp. application, plants inoculated with a control vector nodulated normally, whereas nodulation was almost eliminated in plants inoculated with a vector carrying PsNinA and PsNinC. For plants inoculated with a vector carrying PsNinB, nodulation was reduced by at least 45%. Down-regulation of PsNin transcripts in plants inoculated with vectors carrying PsNin cDNA fragments was confirmed and these plants displayed a relative increase in the root/shoot ratio, as expected if nitrogen fixation had been impaired.