Distinguishing the molecular diversity, nutrient content, and energetic potential of exometabolomes produced by macroalgae and reef-building corals

Metabolites exuded by primary producers comprise a significant fraction of marine dissolved organic matter, a poorly characterized, heterogenous mixture that dictates microbial metabolism and biogeochemical cycling. We present a foundational untargeted molecular analysis of exudates released by coral reef primary producers using liquid chromatography-tandem mass spectrometry to examine compounds produced by two coral species and three types of algae (macroalgae, turfing microalgae, and crustose coralline algae [CCA]) from Mo'orea, French Polynesia. Of 10,568 distinct ion features recovered from reef and mesocosm waters, 1,667 were exuded by producers; the majority (86%) were organism specific, reflecting a clear divide between coral and algal exometabolomes. These data allowed us to examine two tenets of coral reef ecology at the molecular level. First, stoichiometric analyses show a significantly reduced nominal carbon oxidation state of algal exometabolites than coral exometabolites, illustrating one ecological mechanism by which algal phase shifts engender fundamental changes in the biogeochemistry of reef biomes. Second, coral and algal exometabolomes were differentially enriched in organic macronutrients, revealing a mechanism for reef nutrient-recycling. Coral exometabolomes were enriched in diverse sources of nitrogen and phosphorus, including tyrosine derivatives, oleoyl-taurines, and acyl carnitines. Exometabolites of CCA and turf algae were significantly enriched in nitrogen with distinct signals from polyketide macrolactams and alkaloids, respectively. Macroalgal exometabolomes were dominated by nonnitrogenous compounds, including diverse prenol lipids and steroids. This study provides molecular-level insights into biogeochemical cycling on coral reefs and illustrates how changing benthic cover on reefs influences reef water chemistry with implications for microbial metabolism.

Database of Immune Cell EQTLs, Expression, Epigenomics

Database of Immune Cell EQTLs, Expression, Epigenomics (DICE, dice-database.org) is a freely accessible web resource for diving deep into RNA-seq data across 13 human immune cell type (subsets of T cells, B cells, monocytes and NK cells), in a cohort of 91 healthy, genotyped donors1. The site is composed of four main modules that allow users to view the integrated data by gene, limit the scope to individual cell types, compare expression across cell types, and explore the effect of SNPs on gene expression. The site is optimized to be accessible on both desktop and mobile devices. DICE is an evolving resource with data for additional cell types being deposited on a continuous basis, with 3 additional B cell subsets being next in line. In addition to the core database website, an associated tools website (tools.dice-database.org) is actively being developed and currently hosts tools that operate on lists of genes to perform interactive GO enrichment analysis (GOnet), identify cell types most likely responsible for expression of a set of genes (CellTypeScorer), and examine GeneNetworks deduced from gene co-expression analysis.

Impact of genetic polymorphisms on human immune cell gene expression

While many genetic variants have been associated with risk for human diseases, how these variants affect gene expression in various cell types remains largely unknown. To address this gap, the DICE (database of immune cell expression, expression quantitative trait loci (eQTLs), and epigenomics) project was established. Considering all human immune cell types and conditions studied, we identified cis-eQTLs for a total of 12,254 unique genes, which represent 61% of all protein-coding genes expressed in these cell types. Strikingly, a large fraction (41%) of these genes showed a strong cis-association with genotype only in a single cell type. We also found that biological sex is associated with major differences in immune cell gene expression in a highly cell-specific manner. These datasets will help reveal the effects of disease risk-associated genetic polymorphisms on specific immune cell types, providing mechanistic insights into how they might influence pathogenesis (https://dice-database.org).

Generating lung tumor internal target volumes from 4D-PET maximum intensity projections

PURPOSE

Positron emission tomography (PET) of lung tumors suffers from breathing-motion induced blurring. Respiratory-correlated PET ameliorates motion blurring and enables visualization of lung tumor functional uptake throughout the breathing cycle but has achieved limited clinical use in radiotherapy planning. In this work, the authors propose a process for generating a gated PET maximum intensity projection (MIP), a breathing-phase projection of the 4D image set comprising gated PET images, as a technique to quantitatively and efficiently incorporate respiratory-correlated PET information into radiotherapy treatment planning.

METHODS

4D-CT and respiratory-gated PET using [(18)F]fluorodeoxyglucose (FDG) were acquired of three patients with a total of four small (4-18 cc), clearly defined lower-lobe lung tumors. Internal target volumes (ITVs) for the lung tumors were generated by threshold-based segmentation of PET-MIP images and ungated PET images (ITV(PET-MIP) and ITV(3D-PET), respectively), and by manual contouring of CT-MIP and end-exhale and end-inhale phases of 4D-CT (ITV(CT-MIP)) by a radiation oncologist. Because of the sensitivity of tumor segmentation to threshold value, several different thresholds were tested for ITV generation, including 40%, 30%, and 20% of maximum standardized uptake value (SUV(max)) for FDG as well as absolute SUV thresholds of 2.5 and 3.0. The normalized overlap and relative volumes of ITV(PET-MIP) and ITV(3D-PET) with respect to ITV(CT-MIP) were compared. The images were also visually compared. ITV(CT-MIP) was considered a gold standard for these tumors with CT-visible morphology.

RESULTS

The mean and standard deviation normalized overlap and relative volumes between ITV(PET-MIP) and ITV(CT-MIP) were 0.68 ± 0.07 and 1.07 ± 0.42, respectively, averaged over all four tumors and all five threshold values. The mean and standard deviation normalized overlap and relative volumes of ITV(3D-PET) and ITV(CT-MIP) were 0.47 ± 0.12 and 0.69 ± 0.56, respectively.

CONCLUSIONS

PET-MIP images better match CT-MIP images for this sample of four small CT-visible tumors as compared to ungated PET images, based on the metrics of volumetric overlap and relative volumes as well as visual interpretation. The PET-MIP is a way to incorporate 4D-PET imaging into the process of lung tumor contouring that is time-efficient for the radiation oncologist and involves minimal effort to implement in treatment planning software, because it requires only a single PET image beyond contouring on CT alone.

gamma-Linolenic acid treatment of rheumatoid arthritis. A randomized, placebo-controlled trial

OBJECTIVE

To assess the clinical efficacy and adverse effects of gamma-linolenic acid (GLA), a plant seed oil-derived unsaturated fatty acid that suppresses inflammation and joint tissue injury in animal models, in the treatment of active rheumatoid arthritis (RA).

METHODS

Fifty-six patients with active RA were randomized to treatment groups in a 6-month, double-blind trial of GLA versus placebo. This was followed by a 6-month, single-blind trial during which all patients received GLA. Patients were treated with 2.8 gm/day of GLA as the free fatty acid or with sunflower seed oil (placebo) administered in identical capsules.

RESULTS

Treatment with GLA for 6 months resulted in statistically significant and clinically relevant reductions in the signs and symptoms of disease activity in patients with RA. Overall meaningful responses (at least 25% improvement in 4 measures) were also better in the GLA treatment group (14 of 22 patients versus 4 of 19 in the placebo group; P = 0.015). During the second 6 months, both groups exhibited improvement in disease activity. Thus, patients taking GLA during the entire study showed progressive improvement during the second 6 months. In this group, 16 of 21 patients showed meaningful improvement at 12 months compared with study entry.

CONCLUSION

GLA at doses used in this study is a well-tolerated and effective treatment for active RA. GLA is available as a component of several plant seed oils and is usually taken in far lower doses than were used in this trial. It is not approved in the United States for the treatment of any condition, and should not be viewed as therapy for any disease. Further controlled studies of its in RA are warranted.

Perinatal mortality in the infants of diabetic women

The causes of 50 perinatal deaths which occurred over an 18-year period in the infants of women with either established (n = 205) or gestational (n = 2,442) diabetes were studied. The perinatal mortality rate in these groups was 5.4% and 1.6% respectively and the causes of deaths were similar in both groups. Intrauterine hypoxia was found to be the commonest cause of death, followed by congenital malformations and respiratory distress syndrome. The implications of these findings for measures to reduce such deaths are discussed.

Aerobic exercise in pregnancy

The effect on fetal and maternal outcome in gestational exercise in a recreational athlete was investigated in a 2 1/2-year prospective study. A training effect in a pregnant subject engaged in aerobic exercise was also determined. One hundred forty-one low-risk pregnant subjects had their aerobic capacity tested during the first trimester, during the third trimester, and post partum. Predicted maximum oxygen consumption values were determined by using standard Bruce treadmill protocol during the first and third tests and the Astrand protocol for submaximal testing on a bicycle ergometer during the third trimester. Exercise prescriptions were given. The primiparous and multiparous subjects were randomized into control and exercise groups, differing only in the frequency of aerobic exercise. The results showed that exercise had no associated increase in neonatal morbidity and obstetric complications. All subjects improved or maintained their level of aerobic fitness. The exercisers showed a significant training effect. The disparity in the second test's results may suggest that the physiologic characteristics of pregnancy masked the aerobic improvement.

Initiation and control of ovulation in the mouse luteal phases. Effects of gonadotropins and gonadotropin releasing hormone

The aim of the present study was to examine the induction of ovulation during pregnancy, pseudopregnancy, and suckling-delayed pregnancy in mice using exogenous gonadotropins. The present results demonstrate that there are mature follicles in the ovary which can be induced to ovulate with administration of either exogenous human chorionic gonadotropin (hCG) or luteinizing hormone (LH) during pregnancy (Days 1-12) and pseudopregnancy (Days 4-8) in the mouse. hCG was relatively ineffective in initiating ovulation during suckling-delayed pregnancy, and hCG could not induce ovulation on Days 3-6 in any animals, suggesting that follicular growth is not continuous during suckling-delayed pregnancy in the mouse. Ovulation occurred in pregnant and pseudopregnant mice following injection of gonadotropin releasing hormone (GnRH) in a gelatin delay vehicle. Injection of GnRH in saline did not initiate ovulation in pregnant or pseudopregnant mice. A large release of LH was shown to occur following injection of GnRH in gelatin, but no release occurred after the same dose of GnRH in saline. In conclusion, the experiments demonstrate the existence of mature follicles during murine pregnancy and pseudopregnancy, and the lack of inductable follicles during suckling-delayed pregnancy.

Initiation and control of ovulation in the mouse luteal phases. Effects of oestrogen, progesterone and prolactin

The aim of the present study was to examine the effect of exogenous oestrogen and progesterone on ovulation in early pregnant mice and at the end of pseudopregnancy. The results demonstrate that there are mature follicles during early pregnancy which were induced to ovulate by administration of large doses of oestrogen (greater than or equal to 10 micrograms) on day 4 of pregnancy. Ovulation was also induced by inhibition of progesterone secretion with bromocriptine. If progesterone or prolactin was given in conjunction with bromocriptine, the ovulation effect was abolished. At the end of pseudopregnancy, the spontaneous ovulation was inhibited by injections of progesterone (1.0 mg). Oestrogen given by itself at the end of pseudopregnancy caused the animals to mate earlier than the control animals. This confirms the presence of mature follicles in mice during pregnancy and suggests that the LH peak needed for ovulation can either be provoked by administration of oestrogen or by blocking of progesterone.

Medical police. Politics and police: the fate of John Roberton

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Effects of adrenalectomy on reproduction in the mouse

Survival of mice treated with sesame seed oil after adrenalectomy was very low and suggested no beneficial effect, whereas treatment with progesterone improved the chances of survival. Treatment with desoxycorticosterone acetate (DOCA) and methyl prednisolone acetate also increased the number of animals surviving after adrenalectomy. The corticosteroids were significantly more effective in ensuring survival than was progesterone. There was no significant difference in survival between mice receiving a single injection of 1.0 mg DOCA and those being given an injection of 1.0 mg DOCA per day for 3 days after the operation. To ensure minimum interference of exogenous corticosteroid with the experimental investigation, animals routinely received only a single injection of 1.0 mg DOCA after the operation. The chance of survival after adrenalectomy was higher in pregnant than in non-pregnant mice. There was a significant linear increase in survival during the first 5 days of pregnancy. Progesterone and prolactin both appeared to be involved in increasing the chance of survival in adrenalectomized pregnant mice. Adrenalectomy had no effect on the number of mice mating and ovulating. Adrenalectomized mice were apparently having normal cycles and 4 weeks after adrenalectomy they were able to mate and ovulate. Compensatory ovulation was seen in hemi-ovariectomized mice and was not abolished by adrenalectomy. Implantation was also unaffected by the operation.