Mannose-Binding Lectin Deficiency Is Associated with Myocardial Infarction: The HUNT2 Study in Norway

Objectives

Mannose-binding lectin (MBL) and ficolins activate the complement cascade, which is involved in atherogenesis. Based on a pilot study, we hypothesized that functional polymorphisms in the MBL gene (MBL2) leading to dysfunctional protein are related to development of myocardial infarction (MI). The aim of the present study was to study polymorphisms in MBL2 and ficolin genes in relation to the risk of MI.

Methods and Results

Using the population-based HUNT Study in Norway, 57133 persons were followed up for a first-time MI from 1995–1997 until the end of 2008. The 370 youngest MI patients were matched by age (range 29–62 years) and gender to 370 controls. A younger population was selected because disease in this group might be less dependent on non-genetic risk factors. The study size was based on power calculation. Polymorphisms in MBL2 and in the genes of ficolin-1, ficolin-2 and ficolin-3 were genotyped by pyrosequencing and related to the risk of MI, estimated as odds ratios (OR). Functional haplotypes were analyzed and stringent alpha levels of significance were set by permutation testing. Variant MBL2 haplotypes causing MBL deficiency were associated with a two-fold higher risk of MI (OR 2.04, 95%CI 1.29–3.24). Adjustments for conventional cardiovascular risk factors did not substantially influence the association. The ficolins were not associated with MI risk.

Conclusion

In a young to middle aged and relatively healthy Caucasian population, MBL2 variants related to functional MBL deficiency were associated with a doubling of the risk for MI, independent of conventional risk factors. This supports that MBL deficiency may lead to increased atherosclerosis or development of vulnerable plaques.     

Bacterial diversity in suspected prosthetic joint infections: an exploratory study using 16S rRNA gene analysis

Formation of biofilm is a prominent feature of prosthetic joint infections (PJIs) and constitutes a challenge to current sampling procedures and culture practices. Molecular techniques have a potential for improving diagnosis of biofilm-adapted, slow-growing and non-culturable bacteria. In this exploratory study we investigated the bacterial diversity in specimens from 22 patients clinically suspected of having PJIs. Bacteriological cultures were performed according to standard practice. A total of 55 specimens from 25 procedures ('specimen sets') were submitted to broad range 16S rRNA gene PCR, cloning, sequencing and phylogenetic analysis. More than 40 bacterial taxa within six phyla were identified in 14 specimen sets originating from 11 patients. Direct observation of biofilm was made in selected specimens by fluorescence in situ hydridization. 16S rRNA gene analysis and bacteriological cultures were concordant for 15/25 specimen sets (60%; five positive, 10 negative); additional taxa were detected in four sets by gene analysis, and discrepant results were obtained for six sets, five of which were negative on culture. Polymicrobial communities were revealed in 9/14 sets by gene analysis and 1/10 sets by culture (P?相似文献   

The microorganisms in chronically infected end-stage and non-end-stage cystic fibrosis patients

Patients suffering from cystic fibrosis (CF) develop chronic lung infections because of highly viscous mucus, where bacteria can form biofilms. In this study, we investigated the microorganisms present in the lungs of end-stage and non-end-stage patients using standard culturing techniques and molecular methods. Tissue and sputum samples (n?=?34) from explanted lungs of five end-stage patients were examined along with routine expectorates (n?=?15) from 13 patients with non-end-stage CF, representing earlier stages of chronic lung infections. Previously, using peptide nucleic acid (PNA) fluorescence in situ hybridization (FISH), we have shown that Pseudomonas aeruginosa was the sole pathogen in end-stage CF lungs (Pediatr Pulmonol 2009, 44: 547). In this study, this tendency was supported by the results of real-time PCR, confirming previous results obtained by standard culturing and 16S rRNA gene analysis (J Clin Microbiol 2011, 49: 4352). Conversely, the non-end-stage patients were found to harbor several species by culturing. PNA FISH confirmed heterogeneous microbiota and showed that the bacteria were located in monospecies aggregates with no apparent physical interaction between the different microcolonies. In conclusion, standard culturing identifies the dominating pathogens, which seem to reside in monospecies microcolonies. The possibility of signaling between the distinct microcolonies still has to be verified and elucidated.     

Arv1 promotes cell division by recruiting IQGAP1 and myosin to the cleavage furrow

Cell division is strictly regulated by a diversity of proteins and lipids to ensure proper duplication and segregation of genetic material and organelles. Here we report a novel role of the putative lipid transporter ACAT-related protein required for viability 1 (Arv1) during telophase. We observed that the subcellular localization of Arv1 changes according to cell cycle progression and that Arv1 is recruited to the cleavage furrow in early telophase by epithelial protein lost in neoplasm (EPLIN). At the cleavage furrow Arv1 recruits myosin heavy chain 9 (MYH9) and myosin light chain 9 (MYL9) by interacting with IQ-motif-containing GTPase-activating protein (IQGAP1). Consequently the lack of Arv1 delayed telophase-progression, and a strongly increased incidence of furrow regression and formation of multinuclear cells was observed both in human cells in culture and in follicle epithelial cells of egg chambers of Drosophila melanogaster in vivo. Interestingly, the cholesterol-status at the cleavage furrow did not affect the recruitment of either IQGAP1, MYH9 or MYL. These results identify a novel function for Arv1 in regulation of cell division through promotion of the contractile actomyosin ring, which is independent of its lipid transporter activity.     

Metabolic consequences of limited substrate anion permeability in brown fat mitochondria from a hibernator,the golden hamster

Brown fat mitochondria obtained from a hibernator, the golden hamster, were investigated in order to elucidate the significance of membrane permeability for metabolic functioning at different temperatures. The mitochondria were shown to have active permeases for phosphate and pyruvate, but very poorly developed permeases for di- and tricarboxylate substrate anions. This was shown with both osmotic swelling techniques and respiration-driven uptake studies. It was shown that the very limited malate permeation observed was compatible with it being a non-carrier-mediated diffusion process. The role of malate transport in supporting fatty-acid oxidation in vitro as a function of temperature was studied in detail. The results support our earlier suggestion that physiologically pyruvate carboxylase probably functions to generate oxaloacetate when high concentrations of condensing partner are needed during thermogenesis. They may also explain earlier observations that acetate was produced from palmitoyl-carnitine at low temperatures even when malate was present; this is here shown to be due to the limited malate permeability at these low temperatures. Thus, even at the body temperature of the hibernating hamster (4–5°C), brown fat is probably able to combust fatty acids totally.     

Impact of food supplements on early child development in children with moderate acute malnutrition: A randomised 2 x 2 x 3 factorial trial in Burkina Faso

BackgroundLipid-based nutrient supplements (LNS) and corn–soy blends (CSBs) with varying soy and milk content are used in treatment of moderate acute malnutrition (MAM). We assessed the impact of these supplements on child development.Methods and findingsWe conducted a randomised 2 × 2 × 3 factorial trial to assess the effectiveness of 12 weeks’ supplementation with LNS or CSB, with either soy isolate or dehulled soy, and either 0%, 20%, or 50% of protein from milk, on child development among 6–23-month-old children with MAM. Recruitment took place at 5 health centres in Province du Passoré, Burkina Faso between September 2013 and August 2014. The study was fully blinded with respect to soy quality and milk content, while study participants were not blinded with respect to matrix. This analysis presents secondary trial outcomes: Gross motor, fine motor, and language development were assessed using the Malawi Development Assessment Tool (MDAT). Of 1,609 children enrolled, 54.7% were girls, and median age was 11.3 months (interquartile range [IQR] 8.2–16.0). Twelve weeks follow-up was completed by 1,548 (96.2%), and 24 weeks follow-up was completed by 1,503 (93.4%); follow-up was similar between randomised groups. During the study, 4 children died, and 102 children developed severe acute malnutrition (SAM). There was no difference in adverse events between randomised groups. At 12 weeks, the mean MDAT z-scores in the whole cohort had increased by 0.33 (95% CI: 0.28, 0.37), p < 0.001 for gross motor; 0.26 (0.20, 0.31), p < 0.001 for fine motor; and 0.14 (0.09, 0.20), p < 0.001 for language development. Children had larger improvement in language z-scores if receiving supplements with milk (20%: 0.09 [−0.01, 0.19], p = 0.08 and 50%: 0.11 [0.01, 0.21], p = 0.02), although the difference only reached statistical significance for 50% milk. Post hoc analyses suggested that this effect was specific to boys (interaction p = 0.02). The fine motor z-scores were also improved in children receiving milk, but only when 20% milk was added to CSB (0.18 [0.03, 0.33], p = 0.02). Soy isolate over dehulled soy increased language z-scores by 0.07 (−0.01, 0.15), p = 0.10, although not statistically significant. Post hoc analyses suggested that LNS benefited gross motor development among boys more than did CSB (interaction p = 0.04). Differences between supplement groups did not persist at 24 weeks, but MDAT z-scores continued to increase post-supplementation. The lack of an unsupplemented control group limits us from determining the overall effects of nutritional supplementation for children with MAM.ConclusionsIn this study, we found that child development improved during and after supplementation for treatment of MAM. Milk protein was beneficial for language and fine motor development, while suggested benefits related to soy quality and supplement matrix merit further investigation. Supplement-specific effects were not found post-intervention, but z-scores continued to improve, suggesting a sustained overall effect of supplementation.Trial registrationISRCTN42569496

In this analysis of secondary trial outcomes, Mette F. Olsen and colleagues show the effects of different supplements on child language and motor skill development.     

Morphological adaptations to induced changes in transepithelial sodium transport in chicken lower intestine (coprodeum): a study of resalination, aldosterone stimulation, and epithelial turnover

Transepithelial sodium transport and epithelial morphology during short-term adaptation to resalination or aldosterone stimulation were studied in the chicken coprodeum. Coprodeum was sampled for light and electron microscopy after 0–3 days of resalination in hens on a low-NaCl diet and after 0–6 days of aldosterone stimulation in hens on a high-NaCl diet. Sodium transport was measured in vitro with Ussing chambers. Plasma osmolality and electrolyte concentrations were measured in aldosterone-stimulated hens. Epithelial proliferation and migration between 1 h and 16 days were investigated in chickens on high-NaCl and low-NaCl diets using a bromodeoxyuridine technique. Resalination abolished the otherwise high sodium transport within 1 day, while the height and number of microvilli, as well as the number of brush cells, decreased over 3 days. Aldosterone stimulation increased sodium transport, the height and number of microvilli, and the brush-cell number. Bromodeoxyuridine studies indicated an epithelial cell turnover of more than 16 days. The results thus demonstrate that epithelial cells have an unusual capacity to adjust rap- idly to variations in sodium intake. A strong correlation between structure and function was apparent.     

Behavioral Responses of Nursing Home Residents to Visits From a Person with a Dog,a Robot Seal or aToy Cat

Previous studies suggest that contact with dogs can positively affect the wellbeing of elderly people in nursing homes, but there is a lack of research investigating the causal pathways of these effects. One such path- way may relate to the behavioral responses of the elderly when interacting with a dog. The present study compared the immediate behavioral responses of nursing home residents to bi-weekly visits from a person accompanied by either a dog, a robot seal (PARO®), or a soft toy cat, using a randomized controlled design. A total of 100 nursing home residents com- pleted the study. Each participant received a total of 12 visits, during which their behaviors, including interactions between the visitor and the accom- panying animal (real or artificial), were recorded. Also, data on cognitive im- pairment, presence of depressive symptoms, age, time lived in the nursing home, dementia diagnoses, and gender were collected. We found that the immediate responses to, and interaction with, the visiting animal depended on the type of animal that was brought along. The dog and the interactive robot seal triggered the most interaction, in the form of physical contact (F(2,103) = 7.50, p < 0.001), eye contact (F(4,151) = 6.26, p < 0.001), and verbal communication (F(4,195) = 2.87, p < 0.05). As well, the cognitive impairment level of the residents affected with whom they interacted. The higher the cognitive impairment level, the more interaction was directed toward the animal and less toward humans, regardless of visit type (F(2,101) = 4.10, p < 0.05). The dogs and the robot seal stimulated the residents to more in- teraction, compared with the toy cat, but the robot seal failed to maintain the attention at the same level over time. The cognitive functioning of the residents correlated with the level of interaction, and this needs to be studied further.