Nomenclature of prokaryotic 'Candidatus' taxa: establishing order in the current chaos

In the mid-1990s, the category 'Candidatus' was established for putative taxa of as yet uncultivated prokaryotes. The status of 'Candidatus' is not formally included in the rules of the International Code of Nomenclature of Prokaryotes. Thus, 'Candidatus' names do not have standing in the nomenclature. Curated annotated lists of 'Candidatus' names (not including phyla) have been published since 2020. By April 2021, about 2700 names of 'Candidatus' taxa had been published. The International Committee on Systematics of Prokaryotes recently rejected proposals to allow gene sequence data as nomenclatural types. An alternative code for naming uncultivated microorganisms (the 'SeqCode') is now being developed for naming the majority of prokaryotes that are as yet uncultivated. In the opinion of the author, there is no need for such a code, as the existing system, with nomenclature quality control also for 'Candidatus' names, fulfills the needs. Computer programs such as GAN which generates large numbers of correctly formed names from the short lists of Latin and Greek word elements and Protologger that produce descriptions directly from genome sequences will become important in the future for automated naming and description of large numbers of 'Candidatus' taxa from metagenomic and single cell genome data. However, the formation of interesting and meaningful names is encouraged whenever possible.

P–441 Semen quality and cryopreservation in adolescent transgender females

Study question

What are the semen quality and cryopreservation outcomes among adolescent transgender females at the time of fertility preservation (FP) before initiating gender-affirming hormone (GAH) treatment?

Summary answer

Semen quality is strongly reduced among adolescent transgender females before hormone therapy and their stored sperm samples are suitable for intracytoplasmic sperm injection (ICSI).

What is known already

The age of individuals seeking treatment for gender affirmation has fallen sharply in recent years and many of them are adolescents. Estrogen, the primary treatment for transgender women, is known to impair semen quality and fertility potential. Sperm cryopreservation enables young transgender females to circumvent GAH therapy-related fertility impairment and have genetically related children. There are recent data on semen quality among adult transgender women who preserve fertility before exposure to GAH therapy, but little is known about pubertal transgender female adolescents.

Study design, size, duration

This retrospective cohort study included 26 adolescent transgender females who underwent FP between June 2013 and October 2020.

Participants/materials, setting, methods

Before initiating gonadotropin-releasing hormone agonists solely or with GAH treatment, 25 adolescent transgender females were referred to FP in our Fertility Institute of a tertiary university-affiliated medical center. Pre-freezing semen parameters were compared to WHO 2010 reference values. Post-thaw semen parameters were used to determine adequate assisted reproductive technology (ART). A multivariate linear regression analysis was performed to assess the impact of selected medical and lifestyle factors on the semen quality of our study participants.

Main results and the role of chance

The mean age at which adolescent transgender females underwent sperm cryopreservation was 16.2 ± 1.38 years. The median values of all semen parameters in our study group were significantly lower compared to the WHO data on semen quality in the general population of unscreened men, including volume (1.46 ml vs 3.2 ml, respectively, P = 0.001 ), sperm concertation (28*106/ml vs 64*106/ml, P < 0.001), total sperm number (28.2*106 vs 196*106, P < 0.001), total motility (51.6% vs 62%, P < 0.001), and normal morphology (2% vs 14%, P < 0.001). The frequency of semen abnormalities was teratozoospermia 72%, hypospermia 52%, oligozoospermia 28%, and azoospermia 4%. The median post-thaw total motile count was 0.17*106 per vial, and the quality was adequate only for ICSI in 87.7% of the thawed semen samples. Attention-deficit/hyperactivity disorder (ADHD) diagnosis, history of depression/anxiety, medication for ADHD, and antidepressant drugs were found to correlate with hypospermia. No correlation was found between the time of FP, body mass index, autistic spectrum disorder diagnosis, cannabis use, testis tucking, or the levels of follicle-stimulating hormone, estradiol, and testosterone on the semen parameters.

Limitations, reasons for caution

Because no normal values of semen in adolescents are available and the absence of a matched control group, we used WHO 2010 semen data as reference values, and they may not be representative of the adolescent population.

Wider implications of the findings: Although adolescent transgender females have poor semen quality and limited stored semen samples suitable for advanced ART interventions, even before starting GAH therapy, we highly recommend sperm cryopreservation before initiating GAH treatment and thereby prevent further impairment of sperm quality associated with the hormonal treatment.

Trial registration number

Not applicable

Maternal mediation strategies during interaction with toddlers- a comparison of dyads with autism spectrum disorder (ASD) and dyads with typical development (TD)

Introduction

During interactions with toddlers, mothers use various mediation strategies to encourage mutual play. Such mediation skills play an important role in the development of toddlers’ communicative skills. Autism Spectrum Disorder (ASD) introduces challenges to this interaction.

Objectives

To study the use of maternal strategies during interaction with ASD and TD toddlers at early lexical levels.

Methods

Nine ASD and fifteen TD dyads participated. Toddlers were matched by lexical levels. The mean age in the ASD was 31.5 months and in TD - 17 months. Each dyad was video-recorded three times, during naturalistic interaction. Mothers’ verbal mediation strategies were divided into five main communicative categories.

Results

1. Exact repetition of toddler’s utterances was similarly used and increased in both groups across the three visits (f (2,44)=3.77, p< 0.05). 2. Significant differences were found between the two groups regarding strategies associated with control of the interaction eg mothers of toddlers with ASD (MASD) made more frequent attempts to redirect their child’s attention (F (1,22)= 74.56, p<0.01). 3. MASD had higher indices of overall talkativeness (F (1,22)= 5.43, p<0.05); use of nonverbal means (F(1,22)= 9,51, p<0.01); simultaneous use of different means of communication (F (1,22)=19.8, p<0.01).

Conclusions

Our results highlight that in some respects, maternal mediation strategies reflect the child’s lexical level. However, our main finding is a distinct interaction style expressed in MASD’s elevated use of verbal and nonverbal mediation strategies. This, in hope of maintaining continuous interaction that could not be otherwise achieved due to their toddlers’ difficulties

Disclosure

No significant relationships.

Between Abnormal "Otherness" to Groundbreaking "Uniqueness": The Family-Construction Process of the GLBT Family

The GLBT family is a new postmodern phenomenon demonstrating the accomplishments of marginal groups seeking acceptance within mainstream society. The article is based on a qualitative phenomenological study conducted in Israel during 2012, providing a theoretical model combining a vast number of GLBT parenting options ranging from surrogacy, sperm donation, adoption, and co-parenting. The research consisted of 50 personal interviews that concentrated on the family experiences of couples of gay men and lesbian woman who opted to bring a child into their families. Analysis of the data points to a process of empowerment where societal norms in respect to gender, parenting, and family are deconstructed and then reconstructed. The theoretical model conceptualizes three parenting challenges that highlight the respondent's family experience: "Otherness," belonging, and self-actualization. Research shows that every period of family life addresses a different segment, where one of the three challenges becomes the dominant experience.

Dynamic assessment of the tear film muco-aqueous and lipid layers using a novel tear film imager (TFI)

PURPOSE

The objective of the study was to assess a new technology, the tear film imager (TFI), which can dynamically image the muco-aqueous and lipid layers.

METHODS

Prospective pilot case series of individuals with and without dry eye (DE). Two sequential images were obtained with the TFI. Measurements were assessed for reproducibility and compared with clinically derived DE metrics. Individuals were grouped into DE categories based on signs of DE.

RESULTS

49 patients participated in the study with a mean age of 58.8 years (SD 15.9) and a female majority (69%). Reproducibility of the muco-aqueous layer thickness (MALT) was excellent (r=0.88). MALT measurements significantly correlated with the Schirmer score (r=0.31). Lipid break up time (LBUT) as measured by the TFI significantly correlated with the clinical measure of tear break up time (TBUT) (r=0.73). MALT and LBUT were significantly thinner and shorter, respectively, in the DE groups (mild-moderate and severe) compared with the control group. When comparing TFI parameters to clinically assessed signs, sensitivity of the device was 87% and specificity was 88%.

CONCLUSION

The TFI is the first machine capable of reproducibly measuring muco-aqueous thickness in human subjects which correlates with Schirmer score. In parallel, it assesses other important aspects of tear film function which correlate with clinician assessed DE metrics.

ILDR2 Is a Novel B7-like Protein That Negatively Regulates T Cell Responses

The B7-like protein family members play critical immunomodulatory roles and constitute attractive targets for the development of novel therapies for human diseases. We identified Ig-like domain-containing receptor (ILDR)2 as a novel B7-like protein with robust T cell inhibitory activity, expressed in immune cells and in immune-privileged and inflamed tissues. A fusion protein, consisting of ILDR2 extracellular domain with an Fc fragment, that binds to a putative counterpart on activated T cells showed a beneficial effect in the collagen-induced arthritis model and abrogated the production of proinflammatory cytokines and chemokines in autologous synovial-like cocultures of macrophages and cytokine-stimulated T cells. Collectively, these findings point to ILDR2 as a novel negative regulator for T cells, with potential roles in the development of immune-related diseases, including autoimmunity and cancer.

Gp96 Peptide Antagonist gp96-II Confers Therapeutic Effects in Murine Intestinal Inflammation

Background

The expression of heat shock protein gp96 is strongly correlated with the degree of tissue inflammation in ulcerative colitis and Crohn’s disease, thereby leading us to the hypothesis that inhibition of expression via gp96-II peptide prevents intestinal inflammation.

Methods

We employed daily injections of gp96-II peptide in two murine models of intestinal inflammation, the first resulting from five daily injections of IL-12/IL-18, the second via a single intrarectal application of TNBS (2,4,6-trinitrobenzenesulfonic acid). We also assessed the effectiveness of gp96-II peptide in murine and human primary cell culture.

Results

In the IL-12/IL-18 model, all gp96-II peptide-treated animals survived until day 5, whereas 80% of placebo-injected animals died. gp96-II peptide reduced IL-12/IL-18-induced plasma IFNγ by 89%, IL-1β by 63%, IL-6 by 43% and tumor necrosis factor (TNF) by 70% compared to controls. The clinical assessment Disease Activity Index of intestinal inflammation severity was found to be significantly lower in the gp96-II-treated animals when compared to vehicle-injected mice. gp96-II peptide treatment in the TNBS model limited weight loss to 5% on day 7 compared with prednisolone treatment, whereas placebo-treated animals suffered a 20% weight loss. Histological disease severity was reduced equally by prednisolone (by 40%) and gp96-II peptide (35%). Mice treated with either gp96-II peptide or prednisolone exhibited improved endoscopic scores compared with vehicle-treated control mice: vascularity, fibrin, granularity, and translucency scores were reduced by up to 49% by prednisolone and by up to 30% by gp96-II peptide. In vitro, gp96-II peptide reduced TLR2-, TLR4- and IL-12/IL-18-induced cytokine expression in murine splenocytes, with declines in constitutive IL-6 (54%), lipopolysaccharide-induced TNF (48%), IL-6 (81%) and in Staphylococcus epidermidis-induced TNF (67%) and IL-6 (81%), as well as IL-12/IL-18-induced IFNγ (75%). gp96-II peptide reduced IL–1β, IL-6, TNF and GM-CSF in human peripheral blood mononuclear cells to a similar degree without affecting cell viability, whereas RANTES, IL-25 and MIF were twofold to threefold increased.

Conclusion

gp96-II peptide protects against murine intestinal inflammation by regulating inflammation in vivo and in vitro, pointing to its promise as a novel treatment for inflammatory bowel disease.

Induction of immune tolerance by CGEN-15001, a novel immunomodulatory Fc fusion protein of the B7 family (THER5P.823)

We discovered a novel immune checkpoint protein based on characteristics of the B7/CD28 family. CGEN-15001 is a fusion protein composed of the extracellular domain of this protein fused to IgG Fc. CGEN-15001 inhibits T cell activation, demonstrates immunomodulation by inhibiting pro-inflammatory Th1 and Th17 responses while promoting anti-inflammatory IL-10 and Th2 responses, and enhances iTreg differentiation. CGEN-15001 is efficacious in animal models of autoimmunity such as multiple sclerosis (MS), rheumatoid arthritis, type1 diabetes (T1D) and psoriasis. In the EAE model of MS and in the NOD model of T1D, short 2-week treatment with CGEN-15001 resulted in long term inhibition of disease. In the T1D model, mice treated with CGEN-15001 retained normal blood glucose levels18 weeks after cessation of treatment. To further study tolerance induction, the H-Y minor Ag mismatch bone marrow transplantation model was used. CGEN-15001 treatment resulted in graft survival and increase in Tregs, indicating donor specific tolerance induction. The prolonged therapeutic responses in models of autoimmunity and the prevention of graft rejection, imply establishment of immune tolerance by CGEN-15001. Taken together, the mode of action of CGEN-15001 that combines inhibition of autoreactive cells, immunomodulation and restoration of immune tolerance, suggests it should provide long standing and safe therapy for autoimmune diseases.

Abstract B291: Identification of novel immune checkpoints and their implementation as mAb targets for cancer immunotherapy

Immune checkpoints, such as CTLA4 and PD-1, have emerged as promising drug targets for cancer immunotherapy. We hypothesize that additional novel members of the B7/CD28 family play a role in T cell regulation and thus may serve as targets for therapeutic mAbs. However, the discovery of novel family members is challenging since proteins of the immune system, including proteins of the B7 protein In order to identify novel members of the B7/CD28 protein family, Compugen has developed a discovery approach integrating gene and protein information with extensive expression data, and has identified nine novel membrane proteins that possess characteristics of the B7/CD28 protein family members and are therefore predicted to play a role in T cell co-stimulation.

In order to validate our predictive discovery findings, we evaluated the effect of our proteins on immune cells, particularly T cells. For that goal, we expressed the proteins on the cell surface upon ectopic expression, and also produced fusion proteins consisting of the extracellular domain of the predicted proteins, fused to an IgG Fc domain. Here we present results obtained for two of our novel proteins, CGEN-15001T and CGEN-15022. Both display robust inhibition of T cell activation. Interestingly, CGEN-15001, one of the Fc-fused proteins, leads to increased levels of anti-inflammatory cytokines such as IL-4 and IL5, while reducing pro-inflammatory cytokines such as IFN-γ and IL-17. In addition, CGEN-15001 was found to enhance iTregs differentiation. Furthermore, these molecules showed therapeutic efficacy in mouse models of multiple sclerosis and rheumatoid arthritis.

To investigate the potential of these membrane proteins as drug targets for treatment of cancer we have performed extensive IHC studies, on a variety of healthy and malignant tissues. Both CGEN-15001T and CGEN-15022 were found to be expressed in numerous types of cancers, each showing a unique pattern of expression. CGEN-15001T, in addition to its expression on tumor cells, was found to be expressed on tumor infiltrating immune cells, especially on Macrophages and Mast cells.

Based on the immunomodulatory activities and the expression pattern on malignant and immune cells, CGEN15001T and CGEN15022 may serve as mAb targets for cancer immunotherapy.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):B291.

Citation Format: Gady Cojocaru, Ofer Levy, Amir Toporik, Liat Dassa, Iris Hecht, Ilan Vaknin, Sergey Nemzer, Tania Pergan, Amit Novik, Shirley Sameah-Greenwald, Anat Oren, Zohar Tiran, Peter Steinberger, Joseph Podojil, Nora Tarcic, Eyal Neria, Galit Rotman, Zurit Levine. Identification of novel immune checkpoints and their implementation as mAb targets for cancer immunotherapy. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr B291.

Influence of emulsifier structure on lipid bioaccessibility in oil-water nanoemulsions

The influence of several nonionic surfactants (Tween-20, Tween-40, Tween-60, Span-20, Span-60, or Span-80) and anionic surfactants (sodium lauryl sulfate, sodium stearoyl lactylate, and sodium stearyl fumarate) showed drastic differences in the rank order of lipase activity/lipid bioaccessibility. The biophysical composition of the oil and water interface has a clear impact on the bioaccessibility of fatty acids (FA) by altering the interactions of lipase at the oil-water interface. It was found that the bioaccessibility was positively correlated with the hydrophilic/lipophilic balance (HLB) of the surfactant and inversely correlated to the surfactant aliphatic chain length. Furthermore, the induction time in the jejunum increased as the HLB value increased and decreased with increasing aliphatic chain length. The rate of lipolysis slowed in the jejunum with increasing HLB and with increasing aliphatic chain length.

Do health policy advisors know what the public wants? An empirical comparison of how health policy advisors assess public preferences regarding smoke-free air, and what the public actually prefers

BACKGROUND

Health policy-making, a complex, multi-factorial process, requires balancing conflicting values. A salient issue is public support for policies; however, one reason for limited impact of public opinion may be misperceptions of policy makers regarding public opinion. For example, empirical research is scarce on perceptions of policy makers regarding public opinion on smoke-free public spaces.

METHODS

Public desire for smoke-free air was compared with health policy advisor (HPA) perception of these desires. Two representative studies were conducted: one with the public (N = 505), and the other with a representative sample of members of Israel's health-targeting initiative, Healthy Israel 2020 (N = 34), in December 2010. Corresponding questions regarding desire for smoke-free areas were asked. Possible smoke-free areas included: 100% smoke-free bars and pubs; entrances to health facilities; railway platforms; cars with children; college campuses; outdoor areas (e.g., pools and beaches); and common areas of multi-dweller apartment buildings. A 1-7 Likert scale was used for each measure, and responses were averaged into a single primary outcome, DESIRE. Our primary endpoint was the comparison between public preferences and HPA assessment of those preferences. In a secondary analysis, we compared personal preferences of the public with personal preferences of the HPAs for smoke-free air.

RESULTS

HPAs underestimated public desire for smoke-free air (Public: Mean: 5.06, 95% CI:[4.94, 5.17]; HPA: Mean: 4.06, 95% CI:[3.61, 4.52]: p < .0001). Differences at the p = .05 level were found between HPA assessment and public preference for the following areas: 100% smoke-free bars and pubs; entrances to healthcare facilities; train platforms; cars carrying children; and common areas of multi-dweller apartment buildings. In our secondary comparison, HPAs more strongly preferred smoke-free areas than did the public (p < .0001).

CONCLUSIONS

Health policy advisors underestimate public desire for smoke-free air. Better grasp of public opinion by policy makers may lead to stronger legislation. Monitoring policy-maker assessment of public opinion may shed light on incongruities between policy making and public opinion. Further, awareness of policy-maker misperceptions may encourage policy-makers to demand more accurate information before making policy.

Bacterioruberin and salinixanthin carotenoids of extremely halophilic Archaea and Bacteria: a Raman spectroscopic study

Laboratory cultures of a number of red extremely halophilic Archaea (Halobacterium salinarum strains NRC-1 and R1, Halorubrum sodomense, Haloarcula valismortis) and of Salinibacter ruber, a red extremely halophilic member of the Bacteria, have been investigated by Raman spectroscopy using 514.5nm excitation to characterize their carotenoids. The 50-carbon carotenoid α-bacterioruberin was detected as the major carotenoid in all archaeal strains. Raman spectroscopy also detected bacterioruberin as the main pigment in a red pellet of cells collected from a saltern crystallizer pond. Salinibacter contains the C40-carotenoid acyl glycoside salinixanthin (all-E, 2'S)-2'-hydroxy-1'-[6-O-(methyltetradecanoyl)-β-d-glycopyranosyloxy]-3',4'-didehydro-1',2'-dihydro-β,ψ-carotene-4-one), for which the Raman bands assignments of are given here for the first time.

Public support for smoke-free areas in Israel: a case for action

OBJECTIVE

Secondhand smoke exposure (SHSe) harms adults and children. Though most governments are obliged by international health treaty to protect nonsmokers from SHSe, few adequately do so. Public opinion can provide a powerful mandate for smoke-free policies, but a representative public voice is often absent from the political discussion. For example, following Cabinet approval of a national tobacco control plan, Israel remains embroiled in stormy debate about smoke-free legislation. This debate has unfolded without benefit of current empirical evidence on nationwide public support. The present study reports and assesses public opinion regarding smoke-free places.

METHODS

A nationally representative survey (n=505) was conducted in December, 2010. The response rate was 61%.

RESULTS

Public opinion supports smoke-free air in many places. There was broad consensus among current, former, and never-smokers for smoke-free cars carrying children (94.4%), and smoke-free healthcare facility entrances (92.6%). A clear majority (67.0%) supported completely smoke-free bars and pubs. Nearly half (47.3%) supported eliminating school staff smoking rooms.

CONCLUSIONS

These data strengthen the case for the recent government-approved tobacco control plan. Valid data regarding public opinion on tobacco control can facilitate passage and implementation of smoke-free legislation, thus speeding transition to smoke-free societies.

Increased cord serum inflammatory markers in small-for-gestational-age neonates

OBJECTIVE

The pathological picture in ischemic tissue injury shares features with the inflammatory response. Hypoxia-mediated induction of interleukin-6 (IL-6) could set in motion the mechanisms limiting inflammation in ischemia. Intrauterine growth restriction (IUGR) represents a human model of chronic fetal hypoxia. The purpose of this study was a first-time exploration to determine whether cord blood obtained at the delivery of small-for-gestational-age (SGA) infants has increased concentrations of inflammatory markers.

STUDY DESIGN

Cord blood was collected from 20 SGA (term and near-term) infants and 20 appropriate-for-gestational-age (AGA) controls. Infants exposed to maternal smoking, diabetes, maternal chronic diseases, or alcohol or drug use were excluded. Both groups had Apgar score ≥7 at 1 min with a normal cord pH (>7.25). Cord-serum cytokines and thrombopoietin (TPO) levels were measured by enzyme linked immunosorbent assay. C-reactive protein (CRP) was measured using a turbidometric immunoassay.

RESULT

SGA infants had a significantly smaller birth weight than AGA controls, with a smaller gestation age by 1 week. There were significant elevations in IL-6, tumor necrosis factor (TNF-α), CRP and TPO in the SGA compared with the AGA group, which persisted in multiple regression analysis even after gestational age was taken into account.

CONCLUSION

As hypothesized, significant increases in the cord blood concentrations of known inflammatory markers were found in SGA infants compared with the controls.

Increased cord serum inflammatory markers in small-for-gestational-age neonates

OBJECTIVE

The pathological picture in ischemic tissue injury shares features with the inflammatory response. Hypoxia-mediated induction of interleukin-6 (IL-6) could set in motion the mechanisms limiting inflammation in ischemia. Intrauterine growth restriction (IUGR) represents a human model of chronic fetal hypoxia. The purpose of this study was a first-time exploration to determine whether cord blood obtained at the delivery of small-for-gestational-age (SGA) infants has increased concentrations of inflammatory markers.

STUDY DESIGN

Cord blood was collected from 20 SGA (term and near-term) infants and 20 appropriate-for-gestational-age (AGA) controls. Infants exposed to maternal smoking, diabetes, maternal chronic diseases, or alcohol or drug use were excluded. Both groups had Apgar score ≥7 at 1 min with a normal cord pH (>7.25). Cord-serum cytokines and thrombopoietin (TPO) levels were measured by enzyme linked immunosorbent assay. C-reactive protein (CRP) was measured using a turbidometric immunoassay.

RESULT

SGA infants had a significantly smaller birth weight than AGA controls, with a smaller gestation age by 1 week. There were significant elevations in IL-6, tumor necrosis factor (TNF-α), CRP and TPO in the SGA compared with the AGA group, which persisted in multiple regression analysis even after gestational age was taken into account.

CONCLUSION

As hypothesized, significant increases in the cord blood concentrations of known inflammatory markers were found in SGA infants compared with the controls.

Quantum yields for oxygenic and anoxygenic photosynthesis in the cyanobacterium Oscillatoria limnetica

A comparison of the quantum yield spectra of the oxygenic (H(2)O as the electron donor) with the anoxygenic (H(2)S as the electron donor) photosynthesis of the cyanobacterium, Oscillatoria limnetica reveals that anoxygenic photosynthesis is driven by photosystem I only. The highest quantum yields of the latter (maximum; 0.059 CO(2) molecules/quantum of absorbed light) were obtained with wavelengths which preferentially excite photosystem I (<550, >650) in which chlorophyll a and carotenoids are the major pigments. The addition of 3-(3,4-dichlorophenyl)-1,1-dimethylurea had no effect on anoxygenic photosynthesis, and no enhancement in quantum efficiency was observed by a superimposition of light preferentially exciting photosystem II.Oxygenic photosynthesis efficiently utilizes only a narrow range of the absorption spectrum (550-650 nm) where light is provided in excess to photosystem II via phycocyanin. The quantum yield (0.033 CO(2) molecules/quantum of absorbed light) is lower than the theoretical yield by a factor of 3, possibly due to inefficient light transfer from photosystem II to I. Thus, 3-fold enhancement of oxygenic photosynthesis by superimposition of photosystem I light, and low quantum yields for anoxygenic photosynthesis, were obtained in this region. These results are consonant with the suggestion that such a cyanobacterium represents an intermediate stage in phototrophic evolution.

Accumulation of trehalose and sucrose in cyanobacteria exposed to matric water stress

The drought-resistant cyanobacteria Phormidium autumnale, strain LPP(4), and a Chroococcidiopsis sp. accumulated trehalose, sucrose, and both trehalose and sucrose, respectively, in response to matric water stress. Accumulated sugar concentrations reached values of up to 6.2 mug of trehalose per mug of chlorophyll in P. autumnale, 6.9 mug of sucrose per mug of chlorophyll in LPP(4), and 4.1 mug of sucrose and 3.2 mug of trehalose per mug of chlorophyll in the Chroococcidiopsis sp. The same sugars were accumulated by these cyanobacteria in similar concentrations under osmotic water stress. Cyanobacteria that did not show drought resistance (Plectonema boryanum and Synechococcus strain PCC 7942) did not accumulate significant amounts of sugars when matric water stress was applied.

Prohepcidin concentrations and erythroid progenitors in cord blood of appropriate versus small for gestational age neonates

OBJECTIVE

Prohepcidin (Pro-Hep), synthesized in the liver, is the prohormone of hepcidin (Hep), which reduces iron absorption in the gut; its synthesis is enhanced by inflammation and is reduced during hypoxia. We aimed to study the hypothesis that infants born small for gestational age (SGA) have reduced cord blood concentrations of Pro-Hep.

STUDY DESIGN

Cord blood was collected from 20 SGA (term and near term >35 week gestation) infants and 20 appropriate for gestational age (AGA) controls. We excluded infants exposed to maternal chronic diseases, smoking, diabetes, alcohol or drug use. Both groups had a 1 min Apgar score above or equal to 7 and had normal cord blood pH (above 7.25). ELISA was used to determine serum concentrations of Pro-Hep and erythropoietin (EPO). Circulating CD71(+)/CD45(-)/SSC(low) cells were measured by flow cytometry as an index of erythroid progenitors.

RESULT

There were no significant differences between groups in terms of hemoglobin concentrations, and Pro-Hep. In contrast, EPO levels and circulating CD71(+)/CD45(-)/SSC(low) erythroid progenitors were significantly higher in the SGA group. These differences remained significant even after controlling for gestational age and gravidity.

CONCLUSION

Contrary to EPO upregulation during intrauterine growth restriction (IUGR), and higher concentrations of circulating erythroid progenitors, Pro-Hep concentration is not affected by IUGR.

Birth size and coronary heart disease risk score in young adulthood. The Atherosclerosis Risk in Young Adults (ARYA) study

Data of the Atherosclerosis Risk in Young Adults (ARYA) study were used to investigate the association between birth size and the absolute risk for coronary heart disease in healthy young adults. The cohort study comprises 750 (46.9% men) subjects born between 1970 and 1973. Birth characteristics were obtained from school health records. At young adulthood, blood pressure, anthropometry and fasting lipid levels were measured. Questionnaires were taken about smoking and diabetes. The young adult 10-year risk for coronary heart disease was calculated using the Framingham risk score. The overall 10-year risk for coronary heart disease was 1.6% (standard deviation (SD) 1.9), 3.0% (SD 1.9) in men and 0.3% (SD 0.2) in women. Using linear regression it was shown that a SD lower birth weight (=0.54 kg) was associated with 0.1% greater risk in the overall population (95% confidence interval (CI): -0.19, -0.004). Similarly, a lower ponderal index at birth was associated with an 0.11% higher risk (95% CI: -0.21, -0.002). These relations were stronger in men. Lower birth length was related with an increased risk in women (-0.02% risk/SD birth length; 95% CI: -0.04, 0.0001). These results suggest that small birth size is associated with an increased risk score for coronary artery disease in young adulthood.

Cytoskeletal and cell contact control of the glucocorticoid pathway

The cytoskeleton is a dynamic network that undergoes restructuring during a variety of cellular events including cell contact formation, cell invasion and the mitotic phase of the cell cycle. Here, we review the contribution of the cytoskeletal network to the inductive activity of glucocorticoids by focusing on the hormonal control of glutamine synthetase in the chick neural retina. Depolymerization of the cytoskeleton in cells of the intact retinal tissue inhibits the hormonal induction of glutamine synthetase, but does not alter the cellular amount of the glucocorticoid-receptor protein or the ability of the receptor molecules to translocate into the nucleus. Inhibition of glutamine synthetase induction occurs via a mechanism that involves elevation of c-Jun protein accumulation and repression of glucocorticoid-receptor transcriptional activity. Unlike growth factors and other c-Jun inducing stimuli that control the transcription of the c-Jun gene, depolymerization of the cytoskeleton elevates c-Jun accumulation by upregulating the translation of the c-Jun transcript. We postulate that the cytoskeletal-dependent increase in c-Jun accumulation is involved in cell contact control of both cell proliferation and transcriptional activity of the glucocorticoid-receptor protein.

The cytoskeletal network controls c-Jun translation in a UTR-dependent manner

The cytoskeleton is a dynamic network that undergoes restructuring during various cellular events, influencing cell proliferation, differentiation, and apoptosis. Here, we report that accumulation of c-Jun, a member of the AP1 family of transcription factors that play a key role in normal and aberrant cell growth, dramatically increases upon depolymerization of the cytoskeleton, and that, unexpectedly, this increase is controlled translationally. Depolymerization of the actin or microtubule network induces an increase in c-Jun accumulation with no corresponding increase in c-Jun mRNA or in the half-life of the c-Jun protein, but rather in the translatability of its transcript. This increase is mediated by the untranslated regions (UTRs) of c-Jun mRNA, and is not dependent on activated mitogen-activated protein kinase pathways. This novel mechanism of c-Jun regulation might be relevant to physiological conditions in which c-Jun plays a pivotal role.

Yeast diversity in hypersaline habitats

Thus far it has been considered that hypersaline natural brines which are subjected to extreme solar heating, do not contain non-melanized yeast populations. Nevertheless we have isolated yeasts in eight different salterns worldwide, as well as from the Dead Sea, Enriquillo Lake (Dominican Republic) and the Great Salt Lake (Utah). Among the isolates obtained from hypersaline waters, Pichia guilliermondii, Debaryomyces hansenii, Yarrowia lipolytica and Candida parapsilosis are known contaminants of low water activity food, whereas Rhodosporidium sphaerocarpum, R. babjevae, Rhodotorula laryngis, Trichosporon mucoides, and a new species resembling C. glabrata were not known for their halotolerance and were identified for the first time in hypersaline habitats. Moreover, the ascomycetous yeast Metschnikowia bicuspidata, known to be a parasite of the brine shrimp, was isolated as a free-living form from the Great Salt Lake brine. In water rich in magnesium chloride (bitterns) from the La Trinitat salterns (Spain), two new species provisionally named C. atmosphaerica - like and P. philogaea - like were discovered.

Determinants of augmentation index in young men: the ARYA study

BACKGROUND

There is an increasing interest in the augmentation index (AIx), the proportion of the central pulse pressure resulting from peripheral arterial wave reflection, which has been related to cardiovascular disease risk and mortality. Most of the data on the AIx have been collected in patients with established cardiovascular disease. In contrast, data in the young are scarce. However, as AIx might be used to evaluate cardiovascular disease risk already at an early age, we aimed to study determinants of AIx in a population of healthy young men.

MATERIALS AND METHODS

Three hundred and thirty males (mean age of 28 years) of the Atherosclerosis Risk in Young Adults study (ARYA-study) were studied in this cross sectional, population-based study. Anthropometrics and risk factors for cardiovascular disease were determined and AIx was estimated by radial applanation tonometry. The data were analysed using linear regression models.

RESULTS

Augmentation index was associated with age, height (inverse), heart rate (inverse) and mean arterial pressure (positive). After adjustment for these determinants, smoking (beta = 0.31%/pack years, 95% CI [0.06; 0.55]) and LDL-cholesterol (beta = 1.28%/(mmol L(-1)), 95% CI [0.04; 2.51]) were statistically significant related to AIx.

CONCLUSIONS

This study among young adult males shows that smoking and LDL-cholesterol are positively related to AIx. These findings support the view that AIx may be used as a marker for early vascular damage and cardiovascular disease risk.

hCHL2, a novel chordin-related gene, displays differential expression and complex alternative splicing in human tissues and during myoblast and osteoblast maturation

Chordin-like cysteine-rich repeats (CRs) are conserved domains present in an expanding family of secreted proteins that associate with members of the TGF beta superfamily. In this study, we report the molecular cloning and characterization of CHL2 (chordin-like 2), a novel protein closely related to CHL (chordin-like). Both are members of the chordin family of proteins, and contain a signal peptide and three CR domains. We found that recombinant human CHL2 (hCHL2) protein is secreted and binds activin A, but not BMP-2, -4, or -6. Expression of hCHL2 mRNA and protein was detected in a variety of human tissues and is particularly abundant in the uterus. Extensive and complex alternative splicing of hCHL2 was observed in different tissues, resulting in several distinct protein isoforms that vary substantially in the presence of a signal peptide and their content of CR domains. Differential expression of CHL2 variants was observed during myoblast and osteoblast differentiation, implying a role for this gene in these physiological processes.

The Atherosclerosis Risk in Young Adults (ARYA) study: rationale and design

INTRODUCTION

Despite recent advances in treatment, cardiovascular disease (CVD) is still health problem number one in western societies. Aiming at specific prevention strategies for high-risk individuals and shifting the available prevention programs towards younger age groups might increase the success of primary prevention. However, before addressing age-specific prevention programs, more insight in the determinants of early vascular damage and increased cardiovascular risk is warranted as well as insight in determinants increased cardiovascular risk, including vascular damage, at an early age. The Atherosclerosis Risk in Young Adults (ARYA) study was specifically designed to address this issue.

OBJECTIVES

The ARYA study started off with studies evaluating (1) whether it is possible to predict cardiovascular risk at young adulthood by routinely measured adolescent data, and (2) evaluating the role of birth characteristics and adolescent characteristics to the development of vascular damage at young adulthood.

METHODS

The ARYA study comprises of two cohorts of young adults. The Utrecht cohort includes 750 young adults, aged 27-30 years. The Hague-cohort includes 261 young adults born between 1963 and 1968. Data on birth characteristics, growth in early infancy as well as adolescent anthropometry, blood pressure, lipids, body mass index were obtained from the original medical records of the Municipal Health Service. In 1999/2001, the extent of subclinical vascular damage was measured using carotid wall thickness and aortic stiffness. Also, data on adult cardiovascular risk profile, bone density and central blood pressure were assessed, fasting blood was drawn and timed overnight urine samples were collected.

CONCLUSION

The ARYA study is aimed to provide data on early determinants of cardiovascular risk, including vascular damage, at an early age. This knowledge enhances the understanding of atherosclerosis development and CVD risk and is needed to improve the available primary prevention programs.

Aortic stiffness and carotid intima-media thickness: two independent markers of subclinical vascular damage in young adults?

BACKGROUND

Previous reports have shown that carotid intima-media thickness (CIMT) and arterial stiffness are strong predictors of subsequent cardiovascular disease (CVD) morbidity and mortality, and are well related to an unfavourable cardiovascular risk profile in middle-aged and older subjects. These similarities suggest that arterial stiffness may play a role in the development of atherosclerosis or vice versa. However, studies show conflicting results and are limited to elderly subjects. To study this issue further, we evaluated the relation of arterial stiffness to subclinical atherosclerosis in 524 healthy young adults, aged 27-30 years.

METHODS AND RESULTS

Aortic stiffness was assessed using pulse wave velocity (PWV) and CIMT was used as measure of subclinical atherosclerosis. The positive crude correlation between for mean arterial pressure adjusted PWV and CIMT (Pearson's correlation coefficient: 0.11; P=0.016) attenuated after adjustment for common determinants of both measurements like gender and age (partial correlation coefficient: 0.03; P=0.512). Furthermore, multivariate linear regression models showed that male gender, age and blood pressure were independent determinants of both CIMT and PWV while body mass index and LDL-cholesterol were independent determinants of CIMT only.

CONCLUSIONS

These observations suggest that in healthy young adults arterial stiffness and CIMT reflect two separate entities of vascular damage.

Change in body mass index from adolescence to young adulthood and increased carotid intima-media thickness at 28 years of age: The Atherosclerosis Risk in Young Adults study

Obesity has become a major health problem in Western societies by increasing the risk of atherosclerosis and cardiovascular disease. Although data on tracking of body mass index (BMI) are available, little is known about the impact of weight change over time on the development of vascular damage.

OBJECTIVE

To evaluate the relationship between adolescent BMI as well as change in BMI from adolescence into young adulthood and cardiovascular risk, as estimated by common carotid intima-media thickness (CIMT).

DESIGN

Cohort study.

SUBJECTS

A total of 750 healthy young adults, aged 27-30 y, who attended secondary school in Utrecht, the Netherlands.

MEASUREMENTS

Data on adolescent weight, height, blood pressure and puberty stage were available from the original school health records of the Municipal Health Service. At young adulthood, a questionnaire on cardiovascular risk factors was completed and fasting blood sample was drawn and common CIMT was measured.

RESULTS

One standard deviation (s.d.) increase in adolescent BMI was associated with 2.3 microm [95% confidence interval (CI): 1.3; 3.3] increase in mean common CIMT in young adults after adjustment for gender, adolescent age, adolescent blood pressure, puberty stage and lumen diameter. Further adjustment for adult cardiovascular risk factors did not change the relationship (linear regression coefficient=2.1 microm/s.d.; 95% CI: 1.0; 3.1). Adjustment for adult BMI attenuated the association (linear regression coefficient=0.9 microm/s.d.; 95% CI: -0.3; 2.2) as the majority of overweight and obese adolescents remained overweight or became obese young adults. Subjects who remained in the upper BMI distribution from adolescence into young adulthood had a significantly higher common CIMT compared to those who showed relative weight loss over time (mean difference 14.7 mum; P<0.001). These latter showed similar CIMT values as individuals with constant low BMI.

CONCLUSION

Adolescent BMI predicts cardiovascular risk, as estimated by common CIMT in young adulthood. Individuals who experience the largest increase in BMI and those who remain overweight over time have the thickest common CIMT.