Morning rapid eye movement sleep naps facilitate broad access to emotional semantic networks

STUDY OBJECTIVES

The goal of the study was to assess semantic priming to emotion and nonemotion cue words using a novel measure of associational breadth for participants who either took rapid eye movement (REM) or nonrapid eye movement (NREM) naps or who remained awake; assess relation of priming to REM sleep consolidation and REM sleep inertia effects.

DESIGN

The associational breadth task was applied in both a priming condition, where cue-words were signaled to be memorized prior to sleep (primed), and a nonpriming condition, where cue words were not memorized (nonprimed). Cue words were either emotional (positive, negative) or nonemotional. Participants were randomly assigned to either an awake (WAKE) or a sleep condition, which was subsequently split into NREM or REM groups depending on stage at awakening.

SETTING

Hospital-based sleep laboratory.

PARTICIPANTS

Fifty-eight healthy participants (22 male) ages 18 to 35 y (Mage = 23.3 ± 4.08 y).

MEASUREMENTS AND RESULTS

The REM group scored higher than the NREM or WAKE groups on primed, but not nonprimed emotional cue words; the effect was stronger for positive than for negative cue words. However, REM time and percent correlated negatively with degree of emotional priming. Priming occurred for REM awakenings but not for NREM awakenings, even when the latter sleep episodes contained some REM sleep.

CONCLUSIONS

Associational breadth may be selectively consolidated during REM sleep for stimuli that have been tagged as important for future memory retrieval. That priming decreased with REM time and was higher only for REM sleep awakenings is consistent with two explanatory REM sleep processes: REM sleep consolidation serving emotional downregulation and REM sleep inertia.

Lack of seasonal variation in bleeding and patient-assessed pain patterns in patients with haemophilia B receiving on-demand therapy

Spontaneous haemorrhage in patients with haemophilia is generally considered to occur randomly and without a predictable temporal or seasonal pattern; however, there is a lack of evidence in the literature on the effects of weather, temperature and atmosphere on bleeding episodes. This post hoc analysis of a multicentre, open-label crossover study examined the influence of seasonality on bleeding frequency and patient-assessed pain in patients with moderately severe and severe (FIX C ≤ 2%) haemophilia B. Fifty patients were enrolled and treated on-demand for 16 weeks; 47 were subsequently randomized to one of two prophylactic regimens (nonacog alfa 100 IU kg⁻¹ once weekly or 50 IU kg⁻¹ twice weekly) for 16 weeks. Patients then underwent an 8-week washout period of on-demand therapy before being crossed over to the other prophylactic regimen for 16 weeks. Bleeding episodes during the on-demand treatment periods were analysed. To assess for temporal trends, data were graphed as scatter plots. The primary end point was the annualized bleeding rate (ABR). Additional measures included raw and median pain scores during every joint bleeding event (spontaneous or traumatic), with pain scored using the Brief Pain Inventory (0 = ‘no pain’ to 10 = ‘pain as bad as you can imagine’). The observed ABRs during the on-demand periods showed no distinguishable trend over time. Analysis of pain associated with joint bleeding episodes also did not demonstrate any discernible temporal trend. No apparent seasonal variation in bleeding pattern or patient-reported pain was observed in this analysis of patients with haemophilia B.

The effect of two different domperidone doses on maternal milk production

BACKGROUND

The benefits of breast milk to the newborn infant are well established. The Canadian Paediatric Society recommends exclusive breastfeeding for the first 6 months of life for healthy, term infants. Mothers of premature newborns, however, may have difficulty providing an adequate supply of breast milk. Domperidone is officially used as a prokinetic agent. However, it is used widely around the world as a galactogogue. Despite its widespread use as a galactogogue, only a small number of investigators have studied domperidone for this indication.

AIMS

The purpose of this study was to determine an optimal dosage of domperidone as a galactogogue.

METHODS

Eligible subjects were randomized to receive domperidone 10 mg 3 times daily or domperidone 20 mg 3 times daily for 4 weeks. At week 5, the frequency was decreased to twice daily in both groups, and finally once daily for week 6.

RESULTS

Over the entire first 4-week period, there was a significant increase in daily milk volumes within each group (P < .01). The between-group difference over this period, although not statistically significant, was clinically significant. Additionally, there was no significant within- or between-group difference during weeks 5 and 6.

CONCLUSION

A dose of domperidone of 20 mg, 3 times daily instead of 10 mg, 3 times daily was associated with a clinical, but not statistically significant, increase in milk production.

Machine Learning Techniques Applied to Profile Mobile Banking Users in India

This paper profiles mobile banking users using machine learning techniques viz. Decision Tree, Logistic Regression, Multilayer Perceptron, and SVM to test a research model with fourteen independent variables and a dependent variable (adoption). A survey was conducted and the results were analysed using these techniques. Using Decision Trees the profile of the mobile banking adopter’s profile was identified. Comparing different machine learning techniques it was found that Decision Trees outperformed the Logistic Regression and Multilayer Perceptron and SVM. Out of all the techniques, Decision Tree is recommended for profiling studies because apart from obtaining high accurate results, it also yields ‘if–then’ classification rules. The classification rules provided here can be used to target potential customers to adopt mobile banking by offering them appropriate incentives.

Acute neck pain referred to the surgeon: Lemierre's syndrome as a differential diagnosis

Lemierre's syndrome is usually reported in the young and in fit individuals. We report a case of an 81-year-old woman who presented with thrombophlebitis of the internal jugular vein with a pulmonary embolism.

Polychlorinated naphthalenes (PCNs) in Irish foods: Occurrence and human dietary exposure

The concentrations of selected polychlorinated naphthalene (PCN) congeners (PCNs 52, 53, 66/67, 68, 69, 71/72, 73, 74 and 75) were determined in 100 commonly consumed foods, in the first study on occurrence of these contaminants in the Republic of Ireland. Congener selection was based on current knowledge on PCN occurrence and toxicology, and the availability of reliable reference standards. The determinations were carried out using validated analytical methodology based on 13C10 labelled internal standardisation and measurement by HRGC-HRMS. The results showed PCN occurrence in the majority of studied foods--milk, fish, dairy and meat products, eggs, animal fat, shellfish, offal, vegetables, cereal products, etc. ranging from 0.09 ng kg(-1) whole weight for milk to 59.3 ng kg(-1) whole weight for fish, for the sum of the measured PCNs. The most frequently detected congeners were PCNs 66/67, PCN 52, and PCN 73. The highest concentrations were observed in fish, which generally showed congener profiles that reflect some commercial mixtures. The data compares well with other recently reported data for Western Europe. The dioxin-like toxicity (PCN TEQ) associated with these concentrations is lower than that reported for chlorinated dioxins or PCBs in food from Ireland. The dietary exposure of the Irish adult population to PCNs was calculated following a probabilistic approach, using the full dataset of occurrence and current consumption data. The estimates of dietary intakes at approximately 0.14 pg TEQ kg bw(-1) month(-1) for adults on an average diet, reflects the relatively lower occurrence levels.

Lack of correlation between enterococcal counts and the presence of human specific fecal markers in Mississippi creek and coastal waters

The objective of this study was to determine whether statistically valid correlations could be shown between enterococcal counts of samples from creek and coastal sites and the presence of two molecular, library-independent markers that specify human and/or sewage pollution. Four hundred ninety samples were collected between August 2007 and April 2009 to determine enterococcal counts and the presence of genetic markers for the sewage indicator organisms Methanobrevibacter smithii and Bacteroidales. The presence of human/sewage markers and enterococcal counts were higher in creek samples than coastal samples, but the higher creek levels did not statistically correlate with the either enterococcal count or the presence of the markers present in coastal samples. Furthermore, there was no correlation between enterococcal counts in coastal samples and either marker at any of the beach sites tested. The results of this investigation in Mississippi coastal waters suggest that human/sewage markers are unlikely to correlate with enterococci counts in the nearshore environment and that enterococcal counts may be indicative of other animal or environmental sources. Additionally, a study comparing conventional gel electrophoresis with capillary electrophoresis did not convincingly establish that one method was better than the other in regard to the results obtained. The capillary method does allow reproducibility of results and the ability to analyze multiple samples in a short period of time; however, the operational expenditures exceed the cost of traditional gel electrophoresis.

Surgically placed wound catheters (SPWC) and local anaesthetic infusion in breast surgery: efficacy and safety analysis

BACKGROUND

The effectiveness of surgically placed wound catheters (SPWC) and local anaesthetic infusion in the management of post-operative pain following breast surgery is controversial. This meta-analysis was performed to assess efficacy SPWC compared to other techniques of pain management.

MATERIAL AND METHODS

The meta-analysis included randomised control trials that compared SPWC with other forms of pain control. Post-operative opioid requirements and pain measured in visual analogue scale (VAS) were analysed using Comprehensive Meta-analysis Software version 2. Literature was reviewed for the safety of the SPWC and local anaesthetic infusion.

RESULTS

Four randomised controlled trials evaluating 147 women were included in the final analysis. The overall standard difference in means was 0.094 and 0.033 for post-operative opioid requirement and pain respectively favouring the SPWC and local anaesthetic infusion group. It is a safe technique with no major adverse events as a result.

CONCLUSION

Surgically placed wound catheters and local anaesthetic infusion is clinically safe in a wide range of surgical procedures on the breast and there appears to be a trend towards improved post operative pain relief. The studies analyzed in this review have several important drawbacks such as inadequate power to detect significant differences (none of them included more than 50 patients). A well designed RCT of patients undergoing breast surgery with an adequate number is of patients required to emphatically demonstrate if the operative site infusion with local anaesthetic solution postoperatively is safe and efficacious compared to opioid based regimens alone for post operative pain relief.

Sentinel lymph node biopsy in early breast cancer surgery--working with the risks of vital blue dye to reap the benefits

AIMS

Sentinel lymph node biopsy (SLNB) is an important method of staging early breast cancer because of the inherent benefits it confers on patients in terms of arm function and quality of life. Its success depends on a high level of accuracy in detecting the sentinel node. This is achieved by a dual mapping technique that employs a radio-labelled nanocolloid and a vital blue dye. The vital dyes however carry the risk of anaphylaxis, and as more surgeons employ SLNB in their daily practice, a proportionate rise in the number of anaphylactic reactions can be expected. A comprehensive review of risks and benefits associated with using vital blues dyes has not been published and therefore a retrospective review was undertaken of the different levels of anaphylaxis associated with vital dyes as well as their benefits in SLNB.

METHODS

An OVID MEDLINE search was performed of the English published literature using appropriate search terms to find published trial data and case series that focused on adverse reactions to vital blue dyes.

RESULTS

The risk of severe anaphylaxis (grade 3) can be as low as 0.06%, and up to 0.4% for patients undergoing SLNB when data is analysed from large trials. Furthermore, adverse reactions associated with blue dyes are reversible with appropriate management.

CONCLUSIONS

Surgeons should continue to use vital dyes to ensure that SLNB remains a highly sensitive procedure.

Distribution of Phage Groups of Staphylococcus aureus in the Years 1927 through 1947

The phage typing patterns of 194 typable strains of Staphylococcus aureus isolated in the years 1927 through 1947 and preserved as stock cultures revealed that 43 strains were of phage type 80/81. The occurrence of other typable strains in the broad phage groups I, II, and III corresponded closely to the frequency distribution of staphylococci reported in 1945 by Wilson and Atkinson.

Effects of a tart cherry juice beverage on the sleep of older adults with insomnia: a pilot study

This study ascertained whether a proprietary tart cherry juice blend (CherryPharm, Inc., Geneva, NY, USA) associated with anecdotal reports of sleep enhancement improves subjective reports of insomnia compared to a placebo beverage. The pilot study used a randomized, double-blind, crossover design where each participant received both treatment and placebo for 2 weeks with an intervening 2-week washout period. Sleep continuity (sleep onset, wake after sleep onset, total sleep time, and sleep efficiency) was assessed by 2-week mean values from daily sleep diaries and disease severity by the Insomnia Severity Index in a cohort of 15 older adults with chronic insomnia who were otherwise healthy. The tart cherry juice beverage was associated with statistically significant pre- to post-treatment improvements on all sleep variables. When compared to placebo, the study beverage produced significant reductions in insomnia severity (minutes awake after sleep onset); no such improvements were observed for sleep latency, total sleep time, or sleep efficiency compared to placebo. Effect sizes were moderate and in some cases negligible. The results of this pilot study suggest that CherryPharm, a tart cherry juice blend, has modest beneficial effects on sleep in older adults with insomnia with effect sizes equal to or exceeding those observed in studies of valerian and in some, but not all, studies of melatonin, the two most studied natural products for insomnia. These effects, however, were considerably less than those for evidence-based treatments of insomnia: hypnotic agents and cognitive-behavioral therapies for insomnia.

Phase I study of bryostatin 1, a protein kinase C modulator, preceding cisplatin in patients with refractory non-hematologic tumors

PURPOSE

Preclinical data suggested that bryostatin-1 (bryo) could potentiate the cytotoxicity of cisplatin when given prior to this drug. We designed a phase I study to achieve tolerable doses and schedules of bryo and cisplatin in combination and in this sequence.

METHODS

Patients with non-hematologic malignancies received bryo followed by cisplatin in several schedules. Bryo was given as an 1 and a 24 h continuous infusion, while cisplatin was always given over 1 h at 50 and 75 mg/m(2); the combined regimen was repeated on an every 3-week and later on an every 2-week schedule. Bryo doses were escalated until recommended phase II doses were defined for each schedule. Patients were evaluated with computerized tomography every 2 cycles.

RESULTS

Fifty-three patients were entered. In an every 2-week schedule, the 1-h infusion of bryo became limited by myalgia that was clearly cumulative. With cisplatin 50 mg/m(2) its recommended phase II dose was 30 microg/m(2). In the 3-week schedule, dose-limiting toxicities were mostly related to cisplatin effects while myalgias were tolerable. Pharmacokinetics unfortunately proved to be unreliable due to bryo's erratic extraction. Consistent inhibition of PKC isoform eta (eta) in peripheral blood mononuclear cells was observed following bryo.

CONCLUSIONS

Bryo can be safely administered with cisplatin with minimal toxicity; however, only four patients achieved an objective response. Modulation of cisplatin cytotoxicity by bryo awaits further insight into the molecular pathways involved.

'It's quite hard to grasp the enormity of it': perceived needs of people upon diagnosis of rheumatoid arthritis

OBJECTIVES

The diagnosis of rheumatoid arthritis (RA) brings rapid pharmacological and multidisciplinary team interventions to address inflammatory processes and symptom management. However, people may also need support on the journey to self-management. The aim of this study was to explore what professional support patients feel they receive upon diagnosis, and what support they feel would be most helpful.

METHODS

Two focus groups comprised patients with at least five years'; disease duration (n = 7), and patients more recently diagnosed (5-18 months, n = 5). The latter had attended at least two appointments in a rheumatology nurse specialist clinic during the previous year, aimed at providing support upon diagnosis. Transcripts were subjected to thematic analysis to identify common issues regarding support needs, which were then grouped into themes. Interviewing and analysis was performed by researchers not involved in clinical care.

RESULTS

Four overarching themes emerged. 'Information' was needed about the symptoms of RA, its management and personal outcome, while 'Support' related to emotional needs ('It's quite hard to grasp the enormity of it'). Information and Support overlapped, in that patients wanted someone to talk to, and to be listened to. These two themes were underpinned by issues of service delivery: 'Choice' (patient or professional to talk to, groups, one-to-one) and 'Involvement' (holistic care, partnership), which overlapped in terms of the opportunity to decide when and which interventions to access.

CONCLUSIONS

People with RA report not only informational, but also emotional support needs at diagnosis. The potential for delivering emotional support to patients around the time of diagnosis warrants further exploration.

Circulating RNA transcripts identify therapeutic response in cystic fibrosis lung disease

RATIONALE

Circulating leukocyte RNA transcripts are systemic markers of inflammation, which have not been studied in cystic fibrosis (CF) lung disease. Although the standard assessment of pulmonary treatment response is FEV(1), a measure of airflow limitation, the lack of systemic markers to reflect changes in lung inflammation critically limits the testing of proposed therapeutics.

OBJECTIVES

We sought to prospectively identify and validate peripheral blood leukocyte genes that could mark resolution of pulmonary infection and inflammation using a model by which RNA transcripts could increase the predictive value of spirometry.

METHODS

Peripheral blood mononuclear cells were isolated from 10 patients with CF and acute pulmonary exacerbations before and after therapy. RNA expression profiling revealed that 10 genes significantly changed with treatment when compared with matched non-CF and control subjects with stable CF to establish baseline transcript abundance. Peripheral blood mononuclear cell RNA transcripts were prospectively validated, using real-time polymerase chain reaction amplification, in an independent cohort of acutely ill patients with CF (n = 14). Patients who responded to therapy were analyzed using general estimating equations and multiple logistic regression, such that changes in FEV(1)% predicted were regressed with transcript changes.

MEASUREMENTS AND MAIN RESULTS

Three genes, CD64, ADAM9, and CD36, were significant and independent predictors of a therapeutic response beyond that of FEV(1) alone (P < 0.05). In both cohorts, receiver operating characteristic analysis revealed greater accuracy when genes were combined with FEV(1).

CONCLUSIONS

Circulating mononuclear cell transcripts characterize a response to the treatment of pulmonary exacerbations. Even in small patient cohorts, changes in gene expression in conjunction with FEV(1) may enhance current outcomes measures for treatment response.

Murine pulmonary response to chronic hypoxia is strain specific

Information concerning the effects of genetic variation between different background strains on hemodynamic, morphometric, and gene expression response to hypoxia would be useful. Three strains of mice were kept in hypoxia and phenotyped followed by gene profiling analysis. Among the variables examined, hematocrit, right heart muscularization, and right ventricular systolic pressure showed a strain-specific effect. Increased gene expression of inflammatory, muscle, and angiogenesis genes were seen in all strains, though the specific genes changed varied among groups. These results suggest that different strains use different gene expression mechanisms to adapt to the challenge of chronic hypoxia, resulting in modified phenotypic changes.

Nursing support at the onset of rheumatoid arthritis: Time and space for emotions, practicalities and self-management

BACKGROUND

Following a diagnosis of rheumatoid arthritis (RA), patients have to adapt to lifelong, unpredictable but repeated episodes of pain and disability, potentially leading to permanent loss of function and its consequences on their lives. We established nurse clinics with the aim of supporting newly diagnosed RA patients in adapting to and managing their long-term condition. The aim of this study was to explore the content of clinic discussions in this new clinical service, in order to ascertain patients' needs upon diagnosis.

METHODS

All clinic letters from the nurse to the family doctor were analysed. Every topic mentioned was systematically coded independently by a researcher and a patient research partner, who compared and agreed codes. Codes were organized into categories, and, finally, into overarching themes.

RESULTS

Twenty-four patients had 74 appointment letters. A total of 79 codes were identified, from which ten categories emerged, and, finally, three overarching themes. The first theme related to 'Emotional support', which underpinned the other two themes and was discussed in almost all appointments. Issues included discussions about the emotional consequences of RA, needing time to adjust, frustration and fears for the future. The second theme 'Practicalities of the treatment of RA', included subordinate themes relating to the nature of RA, such as identity, cause, timeline, consequences and treatment. Medication issues were discussed and referrals to the multidisciplinary team were made. The final theme related to the 'Self-management of RA', and included discussions on physical symptoms and their management.

CONCLUSIONS

The offer to attend a nurse clinic soon after diagnosis allowed RA patients to discuss a wide range of practical and self-management issues. However, most patients also took the opportunity and time to discuss emotional reactions and adaptations to diagnosis. The data suggest an unmet need for emotional support that a nurse clinic might be able to provide.

Neonatal lung side population cells demonstrate endothelial potential and are altered in response to hyperoxia-induced lung simplification

Lung side population (SP) cells are resident lung precursor cells with both epithelial and mesenchymal potential that are believed to play a role in normal lung development and repair. Neonatal hyperoxic exposure impairs lung development leading to a long-term decrease in gas exchange surfaces. The hypothesis that lung SP cells are altered during impaired lung development has not been studied. To address this issue, we characterized the endothelial potential of neonatal lung SP and subsets of lung SP from neonatal mice following hyperoxic exposure during room air recovery. Lung SP cells were isolated and sorted on the basis of their capacity to efflux Hoechst 33342. The lung SP was further sorted based on expression of Flk-1 and CD45. In vitro, both CD45pos/Flk-1pos and CD45neg/Flk-1pos bind isolectin B4 and incorporate LDL and form networks in matrigel, indicating that these populations have endothelial cell characteristics. Hyperoxic exposure of neonatal mice resulted in subtle changes in vascular and alveolar density on P13, which persisted with room air recovery to P41. During room air recovery, a decrease in lung SP cells was detected in the hyperoxic-exposed group on postnatal day 13 followed by an increase on day 41. Within this group, the lung SP subpopulation of cells expressing CD45 increased on day 21, 41, and 55. Here, we show that lung SP cells demonstrate endothelial potential and that the population distribution changes in number as well as composition following hyperoxic exposure. The hyperoxia-induced changes in lung SP cells may limit their ability to effectively contribute to tissue morphogenesis during room air recovery.

Molecular effects of loss of BMPR2 signaling in smooth muscle in a transgenic mouse model of PAH

Idiopathic pulmonary arterial hypertension (IPAH) in human patients is associated with mutations in type 2 receptor for the bone morphogenic protein pathway (BMPR2). Mice expressing an inducible dominant negative form of BMPR2 in smooth muscle develop elevated right ventricular pressures when the transgene is activated. We hypothesized that transcriptional changes in these mice may allow insight into the early molecular events leading to IPAH. Microarray analysis was used to examine the transcriptional changes induced in whole lung by loss of normal smooth muscle cell (SMC) BMPR2 signaling in adult male or female mice (12 wk at time of death) expressing the transgene for either 1 or 8 wk. Our key results include a decrease in markers of smooth muscle differentiation, an increase in cytokines and markers of immune response, particularly in female mice, and a decrease in angiogenesis-related genes. These broad patterns of gene expression appear as early as 1 wk and are well established by 8 wk. Results were confirmed by quantitative RT-PCR to RNA from individual mice. Primary pulmonary artery SMC cultures transfected with small interfering RNA to BMPR2 also show loss of SMC markers myosin heavy chain 11 and calponin by quantitative RT-PCR and Western blot. These studies show classes of genes differentially regulated in response to loss of BMPR2 in SMC in vivo with clear relevance to the IPAH disease process, suggesting that the relevance of BMPR2 dysregulation may extend beyond proliferation.

Patterns of asthma admissions in children

Admissions for childhood asthma have declined over the past 10 years in the U.K. The reasons for this decline are not known. There are few published data on Irish children. The study was completed in a paediatric unit in a regional general hospital, with a stable urban/rural catchment population of approximately 45,000 children under 15 years. H.I.P.E. data on paediatric asthma admissions were analysed from 1990-2004. A prospective study of all acute asthma admissions of children aged 1-14 years over a 12 -month period was also undertaken, data were compared to a similar study in 1990, and a retrospective study in 1995. The number of admissions rose to a peak in 1995, and there was a large decline in the number of admissions thereafter. The fall was most marked in school age children. The prospective study showed that the treatment of asthma in the community, and in hospital was more aggressive. There were more children diagnosed, and on prophylactic therapy prior to admission. There was greater use of oxygen and nebulised ipratropium in hospital; milder cases were discharged sooner. Subjective assessment of severity of attacks on admission indicated increased severity, but objective measures showed less change. We have shown that the fall in asthma admissions was accompanied by more aggressive management in the community, with little changes in the attack severity in those admitted. The reduction in admissions was most evident in school age children. These data are consistent with the hypothesis that better management of asthma in the community is responsible for the reduction in admissions.

Interaction of interleukin-6 and the BMP pathway in pulmonary smooth muscle

The majority of familial pulmonary arterial hypertension (PAH) cases are caused by mutations in the type 2 bone morphogenetic protein receptor (BMPR2). However, less than one-half of BMPR2 mutation carriers develop PAH, suggesting that the most important function of BMPR2 mutation is to cause susceptibility to a "second hit." There is substantial evidence from the literature implicating dysregulated inflammation, in particular the cytokine IL-6, in the development of PAH. We thus hypothesized that the BMP pathway regulates IL-6 in pulmonary tissues and conversely that IL-6 regulates the BMP pathway. We tested this in vivo using transgenic mice expressing an inducible dominant negative BMPR2 in smooth muscle, using mice injected with an IL-6-expressing virus, and in vitro using small interfering RNA (siRNA) to BMPR2 in human pulmonary artery smooth muscle cells (PA SMC). Consistent with our hypothesis, we found upregulation of IL-6 in both the transgenic mice and in cultured PA SMC with siRNA to BMPR2; this could be abolished with p38(MAPK) inhibitors. We also found that IL-6 in vivo caused a twofold increase in expression of the BMP signaling target Id1 and caused increased BMP activity in a luciferase-reporter assay in PA SMC. Thus we have shown both in vitro and in vivo a complete negative feedback loop between IL-6 and BMP, suggesting that an important consequence of BMPR2 mutations may be poor regulation of cytokines and thus vulnerability to an inflammatory second hit.

Mice deficient in galectin-1 exhibit attenuated physiological responses to chronic hypoxia-induced pulmonary hypertension

Pulmonary hypertension (PH) is characterized by sustained vasoconstriction, with subsequent extracellular matrix (ECM) production and smooth muscle cell (SMC) proliferation. Changes in the ECM can modulate vasoreactivity and SMC contraction. Galectin-1 (Gal-1) is a hypoxia-inducible beta-galactoside-binding lectin produced by vascular, interstitial, epithelial, and immune cells. Gal-1 regulates SMC differentiation, proliferation, and apoptosis via interactions with the ECM, as well as immune system function, and, therefore, likely plays a role in the pathogenesis of PH. We investigated the effects of Gal-1 during hypoxic PH by quantifying 1) Gal-1 expression in response to hypoxia in vitro and in vivo and 2) the effect of Gal-1 gene deletion on the magnitude of the PH response to chronic hypoxia in vivo. By constructing and screening a subtractive library, we found that acute hypoxia increases expression of Gal-1 mRNA in isolated pulmonary mesenchymal cells. In wild-type (WT) mice, Gal-1 immunoreactivity increased after 6 wk of hypoxia. Increased expression of Gal-1 protein was confirmed by quantitative Western analysis. Gal-1 knockout (Gal-1(-/-)) mice showed a decreased PH response, as measured by right ventricular pressure and the ratio of right ventricular to left ventricular + septum wet weight compared with their WT counterparts. However, the number and degree of muscularized vessels increased similarly in WT and Gal-1(-/-) mice. In response to chronic hypoxia, the decrease in factor 8-positive microvessel density was similar in both groups. Vasoreactivity of WT and Gal-1(-/-) mice was tested in vivo and with use of isolated perfused lungs exposed to acute hypoxia. Acute hypoxia caused a significant increase in RV pressure in wild-type and Gal-1(-/-) mice; however, the response of the Gal-1(-/-) mice was greater. These results suggest that Gal-1 influences the contractile response to hypoxia and subsequent remodeling during hypoxia-induced PH, which influences disease progression.