Anemia, iron deficiency, and stress fractures in female combatants during 16 months

Yanovich, R, Merkel, D, Israeli, E, Evans, RK, Erlich, T, and Moran, DS. Anemia, iron deficiency, and stress fractures in female combatants during 16 months. J Strength Cond Res 25(12): 3412-3421, 2011-The purpose of this study is to evaluate the hematological profile of military recruits in different settings and training programs and to investigate the link between anemia and iron deficiency with stress fracture (SF) occurrence. We surveyed 3 groups of recruits for 16 months: 221 women (F) and 78 men (M) from 3 different platoons of a gender-integrated combat battalion and a control group (CF) of 121 female soldiers from a noncombat unit. Data were fully collected upon induction and at 4 and 16 months from 48F, 21M, and 31CF. Blood tests, anthropometry, physical aerobic fitness, and SF occurrence were evaluated. On induction day, 18.0 and 19.0% of F and CF were found to be anemic, and 61.4 and 50.9%, respectively, were found to have iron deficiency, whereas 7.7% of M were found to be anemic and 10.2% iron deficient. During the 4 months of army basic training (ABT), anemia and iron deficiency prevalence did not change significantly in any group. After 16-months, anemia prevalence decreased by 8% among F and CF and abated in M. Iron deficiency was prevalent in 50.0, 59.4, and 18.8% of F, CF, and M, respectively. Stress fractures were diagnosed in 14 F during ABT, and they had a significantly higher prevalence (p < 0.05) of anemia and iron deficiency anemia compared to F without SFs. The observed link between anemia and iron deficiency on recruitment day and SFs suggests the importance of screening female combat recruits for these deficiencies. To minimize the health impact of army service on female soldiers, preventative measures related to anemia and iron deficiency should be administered. Further research is needed for evaluating the influence of low iron in kosher meat as a possible explanation for the high prevalence of iron deficiency among young Israeli recruits.     

Prostaglandin E₂ protects murine lungs from bleomycin-induced pulmonary fibrosis and lung dysfunction

Prostaglandin E(2) (PGE(2)) is a lipid mediator that is produced via the metabolism of arachidonic acid by cyclooxygenase enzymes. In the lung, PGE(2) acts as an anti-inflammatory factor and plays an important role in tissue repair processes. Although several studies have examined the role of PGE(2) in the pathogenesis of pulmonary fibrosis in rodents, results have generally been conflicting, and few studies have examined the therapeutic effects of PGE(2) on the accompanying lung dysfunction. In this study, an established model of pulmonary fibrosis was used in which 10-12-wk-old male C57BL/6 mice were administered a single dose (1.0 mg/kg) of bleomycin via oropharyngeal aspiration. To test the role of prostaglandins in this model, mice were dosed, via surgically implanted minipumps, with either vehicle, PGE(2) (1.32 μg/h), or the prostacyclin analog iloprost (0.33 μg/h) beginning 7 days before or 14 days after bleomycin administration. Endpoints assessed at 7 days after bleomycin administration included proinflammatory cytokine levels and measurement of cellular infiltration into the lung. Endpoints assessed at 21 days after bleomycin administration included lung function assessment via invasive (FlexiVent) analysis, cellular infiltration, lung collagen content, and semiquantitative histological analysis of the degree of lung fibrosis (Ashcroft method). Seven days after bleomycin administration, lymphocyte numbers and chemokine C-C motif ligand 2 expression were significantly lower in PGE(2)- and iloprost-treated animals compared with vehicle-treated controls (P < 0.05). When administered 7 days before bleomycin challenge, PGE(2) also protected against the decline in lung static compliance, lung fibrosis, and collagen production that is associated with 3 wk of bleomycin exposure. However, PGE(2) had no therapeutic effect on these parameters when administered 14 days after bleomycin challenge. In summary, PGE(2) prevented the decline in lung static compliance and protected against lung fibrosis when it was administered before bleomycin challenge but had no therapeutic effect when administered after bleomycin challenge.     

Mass spectrometric determination of IgG subclass-specific glycosylation profiles in siblings discordant for myositis syndromes

Many autoimmune conditions are believed to result from chronic inflammation as a consequence of the interaction of genetic and environmental factors in susceptible individuals. One common feature in some autoimmune diseases is the decrease in terminal galactosylation of the constant region N-glycan of the total plasma immunoglobulin. To determine whether a similar pattern is characteristic for the autoimmune disorder myositis, we analyzed the antibody subclass specific glycosylation in patients with myositis, their asymptomatic siblings, and healthy unrelated age- and sex-matched controls. The antibody subclass specific glycosylation was determined from the LC-MS analyses of the IgG glycopeptides generated by trypsin digestion of the antibody heavy chain. The glycosylation profiles of the IgG subclasses were determined relative to the total abundance of all glycoforms. We found elevated amounts of glycoforms lacking terminal galactose in myositis patients. Pairwise statistical analyses reveals that galactosylation is statistically different between the myositis patients and control groups. Furthermore, the trend analysis for glycosylation indicates a pattern of decreasing galactosylation in the order controls ≥ siblings ≥ myositis patients, suggesting the existence of a genetic, immune-related predisposition in the group of asymptomatic siblings that can be detected before the onset of clinical symptoms at the level of plasma proteins.     

Proteomic profiling of S-acylated macrophage proteins identifies a role for palmitoylation in mitochondrial targeting of phospholipid scramblase 3

S-Palmitoylation, the reversible post-translational acylation of specific cysteine residues with the fatty acid palmitate, promotes the membrane tethering and subcellular localization of proteins in several biological pathways. Although inhibiting palmitoylation holds promise as a means for manipulating protein targeting, advances in the field have been hampered by limited understanding of palmitoylation enzymology and consensus motifs. In order to define the complement of S-acylated proteins in the macrophage, we treated RAW 264.7 macrophage membranes with hydroxylamine to cleave acyl thioesters, followed by biotinylation of newly exposed sulfhydryls and streptavidin-agarose affinity chromatography. Among proteins identified by LC-MS/MS, S-acylation status was established by spectral counting to assess enrichment under hydroxylamine versus mock treatment conditions. Of 1183 proteins identified in four independent experiments, 80 proteins were significant for S-acylation at false discovery rate = 0.05, and 101 significant at false discovery rate = 0.10. Candidate S-acylproteins were identified from several functional categories, including membrane trafficking, signaling, transporters, and receptors. Among these were 29 proteins previously biochemically confirmed as palmitoylated, 45 previously reported as putative S-acylproteins in proteomic screens, 24 not previously associated with palmitoylation, and three presumed false-positives. Nearly half of the candidates were previously identified by us in macrophage detergent-resistant membranes, suggesting that palmitoylation promotes lipid raft-localization of proteins in the macrophage. Among the candidate novel S-acylproteins was phospholipid scramblase 3 (Plscr3), a protein that regulates apoptosis through remodeling the mitochondrial membrane. Palmitoylation of Plscr3 was confirmed through (3)H-palmitate labeling. Moreover, site-directed mutagenesis of a cluster of five cysteines (Cys159-161-163-164-166) abolished palmitoylation, caused Plscr3 mislocalization from mitochondrion to nucleus, and reduced macrophage apoptosis in response to etoposide, together suggesting a role for palmitoylation at this site for mitochondrial targeting and pro-apoptotic function of Plscr3. Taken together, we propose that manipulation of protein palmitoylation carries great potential for intervention in macrophage biology via reprogramming of protein localization.     

Synergy between social and private information increases foraging efficiency in ants

Insect societies integrate many information sources to organize collective activities such as foraging. Many ants use trail pheromones to guide foragers to food sources, but foragers can also use memories to find familiar locations of stable food sources. Route memories are often more accurate than trail pheromones in guiding ants, and are often followed in preference to trail pheromones when the two conflict. Why then does the system expend effort in producing and acquiring seemingly redundant and low-quality information, such as trail pheromones, when route memory is available? Here we show that, in the ant Lasius niger, trail pheromones and route memory act synergistically during foraging; increasing walking speed and straightness by 25 and 30 per cent, respectively, and maintaining trail pheromone deposition, but only when used together. Our results demonstrate a previously undescribed major role of trail pheromones: to complement memory by allowing higher confidence in route memory. This highlights the importance of multiple interacting information sources in the efficient running of complex adaptive systems.     

Fatty Acid Labeling from Glutamine in Hypoxia Can Be Explained by Isotope Exchange without Net Reductive Isocitrate Dehydrogenase (IDH) Flux

Acetyl-CoA is an important anabolic precursor for lipid biosynthesis. In the conventional view of mammalian metabolism, acetyl-CoA is primarily derived by the oxidation of glucose-derived pyruvate in mitochondria. Recent studies have employed isotope tracers to show that in cancer cells grown in hypoxia or with defective mitochondria, a major fraction of acetyl-CoA is produced via another route, reductive carboxylation of glutamine-derived α-ketoglutarate (catalyzed by reverse flux through isocitrate dehydrogenase, IDH). Here, we employ a quantitative flux model to show that in hypoxia and in cells with defective mitochondria, oxidative IDH flux persists and may exceed the reductive flux. Therefore, IDH flux may not be a net contributor to acetyl-CoA production, although we cannot rule out net reductive IDH flux in some compartments. Instead of producing large amounts of net acetyl-CoA reductively, the cells adapt by reducing their demand for acetyl-CoA by importing rather than synthesizing fatty acids. Thus, fatty acid labeling from glutamine in hypoxia can be explained by spreading of label without net reductive IDH flux.     

Treatment of Anemia in Inflammatory Bowel Disease– Systematic Review and Meta-Analysis

Background

Anemia is considered the most common systemic complication of inflammatory bowel disease (IBD). We aimed to provide all available evidence regarding the safety and efficacy of therapy existing today to correct anemia in IBD.

Methods

Systematic review and meta-analysis of randomized controlled trials that compared any treatment for anemia in patients with IBD. We searched electronic databases, conference proceedings and clinical trials registries. Two reviewers independently extracted data from included trials. The primary outcome was the effect of treatment for anemia in IBD on the hemoglobin (Hb) response, defined as rate of patients who achieved an increase of 2 g/dl in Hb concentration at the end of the follow-up. Secondary outcomes included disease severity scores, iron indices, Hb levels, inflammatory markers, adverse effects, and mortality. Dichotomous data were analysed by calculating the relative risk (RR) for each trial with the uncertainty in each result being expressed using 95% confidence intervals (CI). A fixed effect model was used, except in the event of significant heterogeneity between the trials (P<0.10, I²>40%), in which we used a random effects model.

Results

Nine trials fulfilled the inclusion criteria, to a total of 973 patients. We were able to perform meta-analysis for intravenous (IV) versus oral iron and for ESAs versus placebo. IV iron was associated with a higher rate of achieving Hb response in comparison to oral iron; RR 1.25 (95% CI 1.04–1.51, I² = 2%, 4 trials), CRP levels and disease activity indexes were not significantly affected by IV iron. IV iron was associated with a decrease in adverse events that required discontinuation of intervention and without an increase in serious adverse.

Discussion

Treatment for anemia in IBD should include IV iron and not oral iron replacement, due to improved Hb response, no added toxicity and no negative effect on disease activity.     

Shedding light on the system: studying embryonic development with light sheet microscopy

Light sheet-based fluorescence microscopy (LSFM) is emerging as a powerful imaging technique for the life sciences. LSFM provides an exceptionally high imaging speed, high signal-to-noise ratio, low level of photo-bleaching and good optical penetration depth. This unique combination of capabilities makes light sheet-based microscopes highly suitable for live imaging applications. There is an outstanding potential in applying this technology to the quantitative study of embryonic development. Here, we provide an overview of the different basic implementations of LSFM, review recent technical advances in the field and highlight applications in the context of embryonic development. We conclude with a discussion of promising future directions.     

Mapping the landscape of host-pathogen coevolution: HLA class I binding and its relationship with evolutionary conservation in human and viral proteins

The high diversity of HLA binding preferences has been driven by the sequence diversity of short segments of relevant pathogenic proteins presented by HLA molecules to the immune system. To identify possible commonalities in HLA binding preferences, we quantify these using a novel measure termed "targeting efficiency," which captures the correlation between HLA-peptide binding affinities and the conservation of the targeted proteomic regions. Analysis of targeting efficiencies for 95 HLA class I alleles over thousands of human proteins and 52 human viruses indicates that HLA molecules preferentially target conserved regions in these proteomes, although the arboviral Flaviviridae are a notable exception where nonconserved regions are preferentially targeted by most alleles. HLA-A alleles and several HLA-B alleles that have maintained close sequence identity with chimpanzee homologues target conserved human proteins and DNA viruses such as Herpesviridae and Adenoviridae most efficiently, while all HLA-B alleles studied efficiently target RNA viruses. These patterns of host and pathogen specialization are both consistent with coevolutionary selection and functionally relevant in specific cases; for example, preferential HLA targeting of conserved proteomic regions is associated with improved outcomes in HIV infection and with protection against dengue hemorrhagic fever. Efficiency analysis provides a novel perspective on the coevolutionary relationship between HLA class I molecular diversity, self-derived peptides that shape T-cell immunity through ontogeny, and the broad range of viruses that subsequently engage with the adaptive immune response.     

Multiple functions for the N-terminal region of Msh6

The eukaryotic mismatch repair protein Msh6 shares five domains in common with other MutS members. However, it also contains several hundred additional residues at its N-terminus. A few of these residues bind to PCNA, but the functions of the other amino acids in the N-terminal region (NTR) are unknown. Here we demonstrate that the Msh6 NTR binds to duplex DNA in a salt-sensitive, mismatch-independent manner. Partial proteolysis, DNA affinity chromatography and mass spectrometry identified a fragment comprised of residues 228–299 of yeast Msh6 that binds to DNA and is rich in positively charged residues. Deleting these residues, or replacing lysines and arginines with glutamate, reduces DNA binding in vitro and elevates spontaneous mutation rates and resistance to MNNG treatment in vivo. Similar in vivo defects are conferred by alanine substitutions in a highly conserved motif in the NTR that immediately precedes domain I of MutS proteins, the domain that interacts with mismatched DNA. These data suggest that, in addition to PCNA binding, DNA binding and possibly other functions in the amino terminal region of Msh6 are important for eukaryotic DNA mismatch repair and cellular response to alkylation damage.