NET formation is a default epigenetic program controlled by PAD4 in apoptotic neutrophils

Neutrophil extracellular traps (NETs) not only counteract bacterial and fungal pathogens but can also promote thrombosis, autoimmunity, and sterile inflammation. The presence of citrullinated histones, generated by the peptidylarginine deiminase 4 (PAD4), is synonymous with NETosis and is considered independent of apoptosis. Mitochondrial- and death receptor-mediated apoptosis promote gasdermin E (GSDME)-dependent calcium mobilization and membrane permeabilization leading to histone H3 citrullination (H3Cit), nuclear DNA extrusion, and cytoplast formation. H3Cit is concentrated at the promoter in bone marrow neutrophils and redistributes in a coordinated process from promoter to intergenic and intronic regions during apoptosis. Loss of GSDME prevents nuclear and plasma membrane disruption of apoptotic neutrophils but prolongs early apoptosis-induced cellular changes to the chromatin and cytoplasmic granules. Apoptotic signaling engages PAD4 in neutrophils, establishing a cellular state that is primed for NETosis, but that occurs only upon membrane disruption by GSDME, thereby redefining the end of life for neutrophils.

Limited plasticity of monocyte fate and function associated with epigenetic scripting at the level of progenitors

Myeloid cell heterogeneity is known, but whether it is cell-intrinsic or environmentally-directed remains unclear. Here, an inducible/reversible system pausing myeloid differentiation allowed the definition of clone-specific functions that clustered monocytes into subsets with distinctive molecular features. These subsets were orthogonal to the classical/nonclassical categorization and had inherent, restricted characteristics that did not shift under homeostasis, after irradiation, or with infectious stress. Rather, their functional fate was constrained by chromatin accessibility established at or before the granulocyte-monocyte or monocyte-dendritic progenitor level. Subsets of primary monocytes had differential ability to control distinct infectious agents in vivo. Therefore, monocytes are a heterogeneous population of functionally restricted subtypes defined by the epigenome of their progenitors that are differentially selected by physiologic challenges with limited plasticity to transition from one subset to another.

H3K36 methylation maintains cell identity by regulating opposing lineage programmes

The epigenetic mechanisms that maintain differentiated cell states remain incompletely understood. Here we employed histone mutants to uncover a crucial role for H3K36 methylation in the maintenance of cell identities across diverse developmental contexts. Focusing on the experimental induction of pluripotency, we show that H3K36M-mediated depletion of H3K36 methylation endows fibroblasts with a plastic state poised to acquire pluripotency in nearly all cells. At a cellular level, H3K36M facilitates epithelial plasticity by rendering fibroblasts insensitive to TGFβ signals. At a molecular level, H3K36M enables the decommissioning of mesenchymal enhancers and the parallel activation of epithelial/stem cell enhancers. This enhancer rewiring is Tet dependent and redirects Sox2 from promiscuous somatic to pluripotency targets. Our findings reveal a previously unappreciated dual role for H3K36 methylation in the maintenance of cell identity by integrating a crucial developmental pathway into sustained expression of cell-type-specific programmes, and by opposing the expression of alternative lineage programmes through enhancer methylation.

Epigenetic reader SP140 loss of function drives Crohn's disease due to uncontrolled macrophage topoisomerases

How mis-regulated chromatin directly impacts human immune disorders is poorly understood. Speckled Protein 140 (SP140) is an immune-restricted PHD and bromodomain-containing epigenetic "reader," and SP140 loss-of-function mutations associate with Crohn's disease (CD), multiple sclerosis (MS), and chronic lymphocytic leukemia (CLL). However, the relevance of these mutations and mechanisms underlying SP140-driven pathogenicity remains unexplored. Using a global proteomic strategy, we identified SP140 as a repressor of topoisomerases (TOPs) that maintains heterochromatin and macrophage fate. In humans and mice, SP140 loss resulted in unleashed TOP activity, de-repression of developmentally silenced genes, and ultimately defective microbe-inducible macrophage transcriptional programs and bacterial killing that drive intestinal pathology. Pharmacological inhibition of TOP1/2 rescued these defects. Furthermore, exacerbated colitis was restored with TOP1/2 inhibitors in Sp140-/- mice, but not wild-type mice, in vivo. Collectively, we identify SP140 as a TOP repressor and reveal repurposing of TOP inhibition to reverse immune diseases driven by SP140 loss.

Brain motor and fear circuits regulate leukocytes during acute stress

The nervous and immune systems are intricately linked¹. Although psychological stress is known to modulate immune function, mechanistic pathways linking stress networks in the brain to peripheral leukocytes remain poorly understood². Here we show that distinct brain regions shape leukocyte distribution and function throughout the body during acute stress in mice. Using optogenetics and chemogenetics, we demonstrate that motor circuits induce rapid neutrophil mobilization from the bone marrow to peripheral tissues through skeletal-muscle-derived neutrophil-attracting chemokines. Conversely, the paraventricular hypothalamus controls monocyte and lymphocyte egress from secondary lymphoid organs and blood to the bone marrow through direct, cell-intrinsic glucocorticoid signalling. These stress-induced, counter-directional, population-wide leukocyte shifts are associated with altered disease susceptibility. On the one hand, acute stress changes innate immunity by reprogramming neutrophils and directing their recruitment to sites of injury. On the other hand, corticotropin-releasing hormone neuron-mediated leukocyte shifts protect against the acquisition of autoimmunity, but impair immunity to SARS-CoV-2 and influenza infection. Collectively, these data show that distinct brain regions differentially and rapidly tailor the leukocyte landscape during psychological stress, therefore calibrating the ability of the immune system to respond to physical threats.

Atorvastatin favorably modulates a clinical hepatocellular carcinoma risk gene signature

Lipophilic but not hydrophilic statins have been shown to be associated with reduced risk for hepatocellular carcinoma (HCC) in patients with chronic viral hepatitis. We investigated differential actions of lipophilic and hydrophilic statins and their ability to modulate a clinical prognostic liver signature (PLS) predicting HCC risk in patients with liver disease. Hepatitis C virus (HCV)–infected Huh7.5.1 cells, recently developed as a model to screen HCC chemopreventive agents, were treated with lipophilic statins (atorvastatin and simvastatin) and hydrophilic statins (rosuvastatin and pravastatin), and then analyzed by RNA sequencing and PLS. Lipophilic statins, particularly atorvastatin, more significantly suppressed the HCV‐induced high‐risk pattern of PLS and genes in YAP and AKT pathway implicated in fibrogenesis and carcinogenesis, compared with the hydrophilic statins. While atorvastatin inhibited YAP activation through the mevalonate pathway, the distinctive AKT inhibition of atorvastatin was mediated by stabilizing truncated retinoid X receptor alpha, which has been known to enhance AKT activation, representing a target for HCC chemoprevention. In addition, atorvastatin modulated the high‐risk PLS in an in vitro model of nonalcoholic fatty liver disease (NAFLD). Conclusion: Atorvastatin distinctively inhibits YAP and AKT activation, which are biologically implicated in HCC development, and attenuates a high‐risk PLS in an in vitro model of HCV infection and NAFLD. These findings suggest that atorvastatin is the most potent statin to reduce HCC risk in patients with viral and metabolic liver diseases.

Human enteric viruses autonomously shape inflammatory bowel disease phenotype through divergent innate immunomodulation

Altered enteric microorganisms in concert with host genetics shape inflammatory bowel disease (IBD) phenotypes. However, insight is limited to bacteria and fungi. We found that eukaryotic viruses and bacteriophages (collectively, the virome), enriched from non-IBD, noninflamed human colon resections, actively elicited atypical anti-inflammatory innate immune programs. Conversely, ulcerative colitis or Crohn's disease colon resection viromes provoked inflammation, which was successfully dampened by non-IBD viromes. The IBD colon tissue virome was perturbed, including an increase in the enterovirus B species of eukaryotic picornaviruses, not previously detected in fecal virome studies. Mice humanized with non-IBD colon tissue viromes were protected from intestinal inflammation, whereas IBD virome mice exhibited exacerbated inflammation in a nucleic acid sensing-dependent fashion. Furthermore, there were detrimental consequences for IBD patient-derived intestinal epithelial cells bearing loss-of-function mutations within virus sensor MDA5 when exposed to viromes. Our results demonstrate that innate recognition of IBD or non-IBD human viromes autonomously influences intestinal homeostasis and disease phenotypes. Thus, perturbations in the intestinal virome, or an altered ability to sense the virome due to genetic variation, contribute to the induction of IBD. Harnessing the virome may offer therapeutic and biomarker potential.

Transcriptional regulation of neural stem cell expansion in the adult hippocampus

Experience governs neurogenesis from radial-glial neural stem cells (RGLs) in the adult hippocampus to support memory. Transcription factors (TFs) in RGLs integrate physiological signals to dictate self-renewal division mode. Whereas asymmetric RGL divisions drive neurogenesis during favorable conditions, symmetric divisions prevent premature neurogenesis while amplifying RGLs to anticipate future neurogenic demands. The identities of TFs regulating RGL symmetric self-renewal, unlike those that regulate RGL asymmetric self-renewal, are not known. Here, we show in mice that the TF Kruppel-like factor 9 (Klf9) is elevated in quiescent RGLs and inducible, deletion of Klf9 promotes RGL activation state. Clonal analysis and longitudinal intravital two-photon imaging directly demonstrate that Klf9 functions as a brake on RGL symmetric self-renewal. In vivo translational profiling of RGLs lacking Klf9 generated a molecular blueprint for RGL symmetric self-renewal that was characterized by upregulation of genetic programs underlying Notch and mitogen signaling, cell cycle, fatty acid oxidation, and lipogenesis. Together, these observations identify Klf9 as a transcriptional regulator of neural stem cell expansion in the adult hippocampus.

In humans and other mammals, a region of the brain known as the hippocampus plays important roles in memory. New experiences guide cells in the hippocampus known as radial-glial neural stem cells (RGLs) to divide to make new neurons and other types of cells involved in forming memories.

Each time an RGL divides, it can choose to divide asymmetrically to maintain a copy of itself and make a new cell of another type, or divide symmetrically (a process known as symmetric self-renewal) to produce two RGLs. Symmetric self-renewal helps to restore and replenish the pool of stem cells in the hippocampus that are lost due to injury or age, allowing us to continue making new neurons.

Proteins known as transcription factors are believed to control how RGLs divide. Previous studies have identified several transcription factors that regulate the RGLs splitting asymmetrically to make neurons and other cells. But the identities of the transcription factors that regulate symmetric self-renewal in the adult hippocampus have remained elusive.

Here, Guo et al. searched for transcription factors that regulate symmetric self-renewal of RGLs in mice. The experiments found that RGLs that are resting and not dividing (referred to as ‘quiescent’) have higher levels of a transcription factor called Klf9 than RGLs that are actively dividing. Loss of the gene encoding Klf9 triggered quiescent RGLs to start dividing, and further experiments showed that Klf9 directly inhibited symmetric self-renewal. Guo et al. then used an approach called in vivo translational profiling to generate a blueprint that revealed new insights into the molecular processes involved in this symmetric division.

These findings pave the way for researchers to develop strategies that may expand the numbers of stem cells in the hippocampus. This could eventually be used to help replenish brain circuits with neurons and improve the memory of individuals with Alzheimer’s disease or other conditions that cause memory loss.

Growth Hormone Releasing Hormone Reduces Plasma Markers of Immune Activation and Hepatic Immune Pathways in Nonalcoholic Fatty Liver Disease

Introduction: The GH/IGF-1 axis affects multiple metabolic pathways, and animal models demonstrate that it also modulates immune function. Little is known, however, regarding effects of augmenting GH secretion on immune function in humans. This study used proteomics and gene set enrichment analysis to assess effects of a GH releasing hormone (GHRH) analog, tesamorelin, on circulating immune markers and immune-related gene pathways in the liver in people with HIV (PWH) and NAFLD. We hypothesized that tesamorelin would decrease circulating markers of immune activation in conjunction with previously reported reductions in visceral fat and hepatic triglyceride. Methods: 92 biomarkers associated with immune function (Olink Immuno-Oncology panel) were measured in plasma samples from 61 PWH with NAFLD who participated in a double-blind, randomized, 12-month trial of tesamorelin versus identical placebo. Proteins differentially altered by tesamorelin at a false discovery rate < 0.1 were considered significantly changed. Gene set enrichment analysis targeted to immune pathways was subsequently performed on liver tissue from serial biopsies. Results: Compared to placebo, tesamorelin decreased circulating concentrations of 13 proteins, including four chemokines (C-C Motif Chemokine Ligands 3 [CCL3, effect size -0.38 Log₂ fold change], 4 [CCL4, -0.36 Log₂ fold change], and 13 [CCL13 or MCP4, -0.42 Log₂ fold change] and interleukin-8 [-0.50 Log₂ fold change]), two cytokines (interleukin-10 [-0.32 Log₂ fold change] and cytokine stimulating factor 1 [-0.22 Log₂ fold change]), and four T-cell associated molecules (CD8A [-0.37 Log₂ fold change], Cytotoxic And Regulatory T Cell Molecule [CRTAM, -0.47 Log₂ fold change], granzyme A [-0.53 Log₂ fold change], and adhesion G protein-coupled receptor G1 [ADGRG1, -0.54 Log₂ fold change]), as well as arginase-1 [-0.95 Log₂ fold change], galectin-9 [-0.26 Log₂ fold change], and hepatocyte growth factor [-0.30 Log₂ fold change]. No proteins in the panel were significantly increased by tesamorelin. Network analysis indicated close interaction among the gene pathways responsible for the reduced proteins, with imputational analyses suggesting down regulation of a closely related cluster of immune pathways. Targeted transcriptomics using tissue from liver biopsy confirmed an end-organ signal of down-regulated immune pathways, including pathways involved in antigen presentation, complement activation, toll like receptor and inflammatory signaling, and T-cell activation. Conclusions: Long-term treatment with tesamorelin decreased circulating markers of T-cell and monocyte/macrophage activity, with corresponding downregulation of immune pathways in the liver. These findings suggest that augmenting pulsatile GH may ameliorate immune activation in a population with metabolic dysregulation and systemic inflammation.

Growth Hormone Releasing Hormone Reduces Circulating Markers of Immune Activation in Parallel with Effects on Hepatic Immune Pathways in Individuals with HIV-Infection and Nonalcoholic Fatty Liver Disease

BACKGROUND

The growth hormone (GH)/insulin-like growth factor-1 (IGF-1) axis modulates critical metabolic pathways; however, little is known regarding effects of augmenting pulsatile GH secretion on immune function in humans. This study used proteomics and gene set enrichment analysis to assess effects of a GH releasing hormone (GHRH) analog, tesamorelin, on circulating immune markers and liver tissue in people with HIV (PWH) and NAFLD.

METHODS

92 biomarkers associated with immunity, chemotaxis, and metabolism were measured in plasma samples from 61 PWH with NAFLD who participated in a double-blind, randomized trial of tesamorelin versus placebo for 12 months. Gene set enrichment analysis was performed on serial liver biopsies targeted to immune pathways.

RESULTS

Tesamorelin, compared to placebo, decreased interconnected proteins related to cytotoxic T-cell and monocyte activation. Circulating concentrations of 13 proteins were significantly decreased, and no proteins increased, by tesamorelin. These included four chemokines (CCL3, CCL4, CCL13 [MCP4], IL8 [CXCL8]), two cytokines (IL-10 and CSF-1), and four T-cell associated molecules (CD8A, CRTAM, GZMA, ADGRG1), as well as ARG1, Gal-9, and HGF. Network analysis indicated close interaction among the gene pathways responsible for these proteins, with imputational analyses suggesting down regulation of a closely related cluster of immune pathways. Targeted transcriptomics using liver tissue confirmed a significant end-organ signal of down-regulated immune activation pathways.

CONCLUSIONS

Long-term treatment with a GHRH analog reduced markers of T-cell and monocyte/macrophage activity, suggesting that augmentation of the GH axis may ameliorate immune activation in an HIV population with metabolic dysregulation, systemic and end organ inflammation.

Type I, II, and III interferon signatures correspond to COVID-19 disease severity

We analyzed the plasma levels of interferons and cytokines, and the expression of interferon-stimulated genes in peripheral blood mononuclear cells in COVID-19 patients with different disease severity. Mild patients exhibited transient type I interferon responses, while ICU patients had prolonged type I interferon responses with hyper-inflammation mediated by interferon regulatory factor 1. Type II interferon responses were compromised in ICU patients. Type III interferon responses were induced in the early phase of SARS-CoV-2 infection, even in convalescent patients. These results highlight the importance of type I and III interferon responses during the early phase of infection in controlling COVID-19 progression.

Liver X receptors are required for thymic resilience and T cell output

The thymus is a primary lymphoid organ necessary for optimal T cell development. Here, we show that liver X receptors (LXRs)—a class of nuclear receptors and transcription factors with diverse functions in metabolism and immunity—critically contribute to thymic integrity and function. LXRαβ-deficient mice develop a fatty, rapidly involuting thymus and acquire a shrunken and prematurely immunoinhibitory peripheral T cell repertoire. LXRαβ’s functions are cell specific, and the resulting phenotypes are mutually independent. Although thymic macrophages require LXRαβ for cholesterol efflux, thymic epithelial cells (TECs) use LXRαβ for self-renewal and thymocytes for negative selection. Consequently, TEC-derived LXRαβ protects against homeostatic premature involution and orchestrates thymic regeneration following stress, while thymocyte-derived LXRαβ limits cell disposal during negative selection and confers heightened sensitivity to experimental autoimmune encephalomyelitis. These results identify three distinct but complementary mechanisms by which LXRαβ governs T lymphocyte education and illuminate LXRαβ’s indispensable roles in adaptive immunity.

Differential Plasma Protein Regulation and Statin Effects in Human Immunodeficiency Virus (HIV)-Infected and Non-HIV-Infected Patients Utilizing a Proteomics Approach

BACKGROUND

People with human immunodeficiency virus (PWH) demonstrate increased atherosclerotic cardiovascular disease (ASCVD). Statins are being studied to prevent ASCVD in human immunodeficiency virus (HIV), but little is known regarding the effects of statins on a broad range of inflammatory and cardiovascular proteins in this population.

METHODS

We used a highly specific discovery proteomic approach (Protein Extension Assay), to determine statin effects on over 350 plasma proteins in relevant ASCVD pathways among HIV and non-HIV groups. Responses to pitavastatin calcium were assessed in 89 PWH in the INTREPID trial and 46 non-HIV participants with features of central adiposity and insulin resistance. History of cardiovascular disease was exclusionary for both studies.

RESULTS

Among participants with HIV, PCOLCE (enzymatic cleavage of type I procollagen) significantly increased after pitavastatin therapy and PLA2G7 (systemic marker of arterial inflammation) decreased. Among participants without HIV, integrin subunit alpha M (integrin adhesive function) and defensin alpha-1 (neutrophil function) increased after pitavastatin therapy and PLA2G7 decreased. At baseline, comparing participants with and without HIV, differentially expressed proteins included proteins involved in platelet and endothelial function and immune activation.

CONCLUSIONS

Pitavastatin affected proteins important to platelet and endothelial function and immune activation, and effects differed to a degree within PWH and participants without HIV.

Vaccine hesitancy and the resurgence of vaccine preventable diseases: the way forward for Malaysia, a Southeast Asian country

This study engaged health professionals in in-depth, semi-structured interviews to explore their opinions concerning the issues surrounding vaccine hesitancy in Malaysia and strategies to improve vaccination to stamp the rise of vaccine preventable diseases (VPDs). Opinions on how to address the resurgence of VPDs in the era of increasing vaccine hesitancy were obtained. Eight health professionals, including geriatricians, pediatricians, microbiologists, public health specialists, and family medicine specialists were interviewed. The influence of anti-vaccination propaganda, past-experience of adverse event following immunization (AEFI), perceived religious prohibition, a belief that traditional complementary and alternative medicine (TCAM) use is safer, pseudoscience beliefs, and anti-vaccine conspiracy theories were identified as reasons for refusing to vaccinate. The interplay of social, cultural and religious perspectives in influencing perceived religious prohibition, pseudoscience beliefs, and the use of TCAM contributing to vaccine refusal was found. Five broad themes emerged from the health professionals regarding strategies to address vaccine hesitancy, including establishing an electronic vaccination registry, increasing public awareness initiatives, providing feedback to the public on the findings of AEFI, training of front-line healthcare providers, and banning the dissemination of anti-vaccine information via social media. With regards to identifying strategies to address the resurgence of VPDs, mandatory vaccination received mixed opinions; many viewed supplementary immunization activity and the prevention of travel and migration of unvaccinated individuals as being necessary. In conclusion, the present study identified unique local cultural, traditional and religious beliefs that could contribute to vaccine hesitancy in addition to issues surrounding vaccination refusal similarly faced by other countries around the world. This information are important for the formulation of targeted intervention strategies to stamp vaccine hesitancy in Malaysia which are also a useful guide for other countries especially in the Southeast Asia region facing similar vaccine hesitancy issues.

Vaccine hesitancy and the resurgence of vaccine preventable diseases: the way forward for Malaysia, a Southeast Asian country

This study engaged health professionals in in-depth, semi-structured interviews to explore their opinions concerning the issues surrounding vaccine hesitancy in Malaysia and strategies to improve vaccination to stamp the rise of vaccine preventable diseases (VPDs). Opinions on how to address the resurgence of VPDs in the era of increasing vaccine hesitancy were obtained. Eight health professionals, including geriatricians, pediatricians, microbiologists, public health specialists, and family medicine specialists were interviewed. The influence of anti-vaccination propaganda, past-experience of adverse event following immunization (AEFI), perceived religious prohibition, a belief that traditional complementary and alternative medicine (TCAM) use is safer, pseudoscience beliefs, and anti-vaccine conspiracy theories were identified as reasons for refusing to vaccinate. The interplay of social, cultural and religious perspectives in influencing perceived religious prohibition, pseudoscience beliefs, and the use of TCAM contributing to vaccine refusal was found. Five broad themes emerged from the health professionals regarding strategies to address vaccine hesitancy, including establishing an electronic vaccination registry, increasing public awareness initiatives, providing feedback to the public on the findings of AEFI, training of front-line healthcare providers, and banning the dissemination of anti-vaccine information via social media. With regards to identifying strategies to address the resurgence of VPDs, mandatory vaccination received mixed opinions; many viewed supplementary immunization activity and the prevention of travel and migration of unvaccinated individuals as being necessary. In conclusion, the present study identified unique local cultural, traditional and religious beliefs that could contribute to vaccine hesitancy in addition to issues surrounding vaccination refusal similarly faced by other countries around the world. This information are important for the formulation of targeted intervention strategies to stamp vaccine hesitancy in Malaysia which are also a useful guide for other countries especially in the Southeast Asia region facing similar vaccine hesitancy issues.

Factors associated with nurses' perceptions about quality of end-of-life care

AIM

To examine the factors associated with nurses' perceptions of the quality of end-of-life care.

BACKGROUND

With increasing demand for hospitals to provide end-of-life care, the low quality of palliative care provided in hospital settings is an issue of growing concern in developing countries. Most dying patients receive their care from general nurses, irrespective of the nurses' specialty or level of training.

METHOD

A structured cross-sectional questionnaire survey was conducted of 553 nurses working at a teaching hospital in Malaysia.

RESULTS

The mean scores for nurses' knowledge about end-of-life care, their attitudes towards end-of-life care and the perceived quality of end-of-life care were low. The factors identified as significantly associated with the quality of end-of-life care were nurses' levels of knowledge and their attitudes towards end-of-life care.

DISCUSSION

Factors that contributed to the low quality of end-of-life care were inadequate knowledge and negative attitudes. These findings may reflect that end-of-life care education is not well integrated into nursing education.

CONCLUSION

The findings of this study suggest that there is a need to increase the nurses' level of knowledge and improve their attitude towards end-of-life care in order to enhance the quality of care provided to dying patients.

IMPLICATIONS FOR NURSING AND HEALTH POLICY

Nurse managers and hospital policymakers should develop strategies to enhance nurses' level of knowledge, as well as providing adequate emotional support for nurses who care for dying patients and their families. Nurses should be proactive in increasing their knowledge and adopting more positive attitudes towards end-of-life care.

Chromatin landscapes and genetic risk in systemic lupus

BACKGROUND

Systemic lupus erythematosus (SLE) is a multi-system, complex disease in which the environment interacts with inherited genes to produce broad phenotypes with inter-individual variability. Of 46 single nucleotide polymorphisms (SNPs) shown to confer genetic risk for SLE in recent genome-wide association studies, 30 lie within noncoding regions of the human genome. We therefore sought to identify and describe the functional elements (aside from genes) located within these regions of interest.

METHODS

We used chromatin immunoprecipitation followed by sequencing to identify epigenetic marks associated with enhancer function in adult neutrophils to determine whether enhancer-associated histone marks were enriched within the linkage disequilibrium (LD) blocks encompassing the 46 SNPs of interest. We also interrogated available data in Roadmap Epigenomics for CD4+ T cells and CD19+ B cells to identify these same elements in lymphoid cells.

RESULTS

All three cell types demonstrated enrichment of enhancer-associated histone marks compared with genomic background within LD blocks encoded by SLE-associated SNPs. In addition, within the promoter regions of these LD blocks, all three cell types demonstrated enrichment for transcription factor binding sites above genomic background. In CD19+ B cells, all but one of the LD blocks of interest were also enriched for enhancer-associated histone marks.

CONCLUSIONS

Much of the genetic risk for SLE lies within or near genomic regions of disease-relevant cells that are enriched for epigenetic marks associated with enhancer function. Elucidating the specific roles of these noncoding elements within these cell-type-specific genomes will be crucial to our understanding of SLE pathogenesis.

Factors influencing registered nurses perception of their overall job satisfaction: a qualitative study

AIM

The purpose of this qualitative descriptive study was to explore factors related to critical care and medical-surgical nurses' job satisfaction as well as dissatisfaction in Iran.

BACKGROUND

Job satisfaction is an important factor in healthcare settings. Strong empirical evidence supports a causal relationship between job satisfaction, patient safety and quality of care.

METHOD

A convenient sample of 85 nurses from surgical, medical and critical care wards of a large hospital was recruited. Ten focus group discussions using a semi-structured interview guide were conducted. Interviews were audio-recorded, transcribed verbatim and analysed using a thematic approach.

FINDINGS

The study identified three main themes that influenced nurses' job satisfaction and dissatisfaction: (1) spiritual feeling, (2) work environment factors, and (3) motivation. Helping and involvement in patient care contributed to the spiritual feeling reported to influence nurses' job satisfaction. For work environment factors, team cohesion, benefit and rewards, working conditions, lack of medical resources, unclear nurses' responsibilities, patient and doctor perceptions, poor leadership skills and discrimination at work played an important role in nurses' job dissatisfaction. For motivation factors, task requirement, professional development and lack of clinical autonomy contributed to nurses' job satisfaction.

CONCLUSION AND IMPLICATIONS FOR NURSING AND HEALTH POLICY

Nurse managers should ensure a flexible practice environment with adequate staffing and resources with opportunities for nurses to participate in hospital's policies and governance. Policy makers should consider nurses' professional development needs, and implement initiatives to improve nurses' rewards and other benefits as they influence job satisfaction.

Stigmatization and discrimination towards people living with or affected by HIV/AIDS by the general public in Malaysia

Globally, HIV/AIDS-related stigma and discriminatory attitudes deter the effectiveness of HIV prevention and care programs. This study investigated the general public's perceptions about HIV/AIDS-related stigma and discrimination towards people living with or affected by HIV/AIDS in order to understand the root of HIV/AIDS-related stigma and discriminatory attitudes. Study was carried out using qualitative focus group discussions (FGD). An interview guide with semi-structured questions was used. Participants were members of the public in Malaysia. Purposive sampling was adopted for recruitment of participants. A total 14 focus group discussions (n = 74) was carried out between March and July 2008. HIV/AIDS-related stigma and discrimination towards people living with HIV/AIDS (PLWHA) was profound. Key factors affecting discriminatory attitudes included high-risk taking behavior, individuals related to stigmatized identities, sources of HIV infection, stage of the disease, and relationship with an infected person. Other factors that influence attitudes toward PLWHA include ethnicity and urban-rural locality. Malay participants were less likely than other ethnic groups to perceive no stigmatization if their spouses were HIV positive. HIV/AIDS-related stigma and discrimination were stronger among participants in rural settings. The differences indicate attitudes toward PLWHA are influenced by cultural differences.

Calculation of energy recovery and greenhouse gas emission reduction from palm oil mill effluent treatment by an anaerobic granular-sludge process

Conventional aerobic and low-rate anaerobic processes such as pond and open-tank systems have been widely used in wastewater treatment. In order to improve treatment efficacy and to avoid greenhouse gas emissions, conventional treatment can be upgraded to a high performance anaerobic granular-sludge system. The anaerobic granular-sludge systems are designed to capture the biogas produced, rendering a potential for claims of carbon credits under the Kyoto Protocol for reducing emissions of greenhouse gases. Certified Emission Reductions (CERs) would be issued, which can be exchanged between businesses or bought and sold in international markets at the prevailing market prices. As the advanced anaerobic granular systems are capable of handling high organic loadings concomitant with high strength wastewater and short hydraulic retention time, they render more carbon credits than other conventional anaerobic systems. In addition to efficient waste degradation, the carbon credits can be used to generate revenue and to finance the project. This paper presents a scenario on emission avoidance based on a methane recovery and utilization project. An example analysis on emission reduction and an overview of the global emission market are also outlined.

Information needs, preferred educational messages and channel of delivery, and opinion on strategies to promote organ donation: a multicultural perspective

INTRODUCTION

This study assessed the information needs, preferred educational messages and channels of delivery, as well as opinions on strategies to promote organ donation. It aimed to provide insight into a culturally sensitive public education campaign to encourage organ donation in diverse ethnic communities in Asia, namely the Malays, Chinese and Indians.

METHODS

A total of 17 focus group discussions with 105 participants were conducted between September and December 2008. The participants were members of the general public aged 18 to 60 years, who were recruited through convenient sampling in the Klang Valley area of Malaysia.

RESULTS

Across ethnic groups, there was a general concern about the mistreatment of the deceased's body in the organ procurement process. The Chinese and Indian participants wanted assurance that the body would be treated with respect and care. The Muslims wanted assurance that the handling of a Muslim's body would follow the rules and regulations of the Islamic faith. The most important information requested by the Muslim participants was whether cadaveric donation is permissible in Islam. A lack of national public education and promotion of organ donation was noted. All the three ethnic groups, especially the Malays, required community and religious leaders for support, encouragement and involvement, as sociocultural influences play a significant role in the willingness to donate organs.

CONCLUSION

The pronounced ethnic differences in information needs suggest that culturally sensitive public educational messages are required. Organ donation and transplantation organisations should work closely with community and religious organisations to address the sociocultural barriers identified.

Cervical cancer screening attitudes and beliefs of Malaysian women who have never had a pap smear: a qualitative study

BACKGROUND

Attitudes toward cervical cancer and participation in early detection and screening services are well known to be profoundly affected by cultural beliefs and norms.

PURPOSE

This study explored the attitudes and sociocultural beliefs on cervical cancer screening among Malaysian women.

METHOD

In this qualitative study, in-depth interviews were conducted with 20 Malaysian women, ages 21 to 56 years, who have never had a Papanicolaou (Pap) smear.

RESULTS

Respondents generally showed a lack of knowledge about cervical cancer screening using Pap smear, and the need for early detection for cervical cancer. Many believed the Pap smear was a diagnostic test for cervical cancer, and since they had no symptoms, they did not go for Pap screening. Other main reasons for not doing the screening included lack of awareness of Pap smear indications and benefits, perceived low susceptibility to cervical cancer, and embarrassment. Other reasons for not being screened were related to fear of pain, misconceptions about cervical cancer, fatalistic attitude, and undervaluation of own health needs versus those of the family.

CONCLUSION

Women need to be educated about the benefits of cervical cancer screening. Health education, counseling, outreach programs, and community-based interventions are needed to improve the uptake of Pap smear in Malaysia.

Knowledge and awareness of cervical cancer and screening among Malaysian women who have never had a Pap smear: a qualitative study

INTRODUCTION

Cervical cancer is one of the commonest cancers in women worldwide. Despite the existence of effective screening using Pap smear, the uptake of screening is poor. A qualitative study was undertaken using face-to-face in-depth interviews to investigate knowledge, attitudes and beliefs on cervical cancer screening of Malaysian women.

METHODS

In-depth interviews were conducted with 20 Malaysian women aged 21-56 years and who have never had a Pap smear test, with the aim to explore their knowledge and awareness of cervical cancer and its screening.

RESULTS

A lack of knowledge on cervical cancer and the Pap smear test was found among the respondents. Many women did not have a clear understanding of the meaning of an abnormal cervical smear and the need for the early detection of cervical cancer. Many believe the purpose of the Pap smear test is to detect existing cervical cancer, leading to the belief that Pap smear screening is not required because the respondents had no symptoms. Despite considerable awareness of a link between cervical cancer and sexual activity, as well as the role of a sexually-transmitted infection, none of the respondents had heard of the human papillomavirus.

CONCLUSION

The findings highlight the importance of emphasising accurate information about cervical cancer and the purpose of Pap smear screening when designing interventions aimed at improving cervical cancer screening for Malaysian women.

Focus group discussion: a tool for health and medical research

Focus group discussion is a research methodology in which a small group of participants gather to discuss a specified topic or an issue to generate data. The main characteristic of a focus group is the interaction between the moderator and the group, as well as the interaction between group members. The objective is to give the researcher an understanding of the participants' perspective on the topic in discussion. Focus groups are rapidly gaining popularity in health and medical research. This paper presents a general introduction of the use of focus groups as a research tool within the context of health research, with the intention of promoting its use among researchers in healthcare. A detailed methodology for the conduct of focus groups and analysis of focus group data are discussed. The potentials and limitations of this qualitative research technique are also highlighted.

Characterization of the pathogenic mechanism of a novel BRCA2 variant in a Chinese family

INTRODUCTION

Germline mutations of BRCA1 and BRCA2 account for the majority of hereditary breast cancers, many of which are classified as variants of unknown significance (VUS). We report the identification of a novel BRCA2 variant (c.7806-9T > G) in a Chinese family with multiple breast cancers and document it as a pathogenic mutation.

METHODS

The proband in this family was diagnosed with breast cancer at age 50 with a strong family history of breast cancer. DNA and RNA were extracted from the blood of the proband and her family, and was used for BRCA gene mutation/deletion screening and RNA splicing analysis.

RESULTS

BRCA2 c.7806-9T > G was identified in the proband, which was suggestive of a variant. This change was also found in two sisters of the proband with a history of breast cancer, as well as from the proband's maternal gastric cancer. The only sibling free of breast cancer did not carry the BRCA2 variant, thus demonstrating that the mutation segregates with the clinical phenotype in this family. RNA analysis on the proband blood sample revealed three aberrant splicing variants: c.7806_7874del, c.7806_7976del, and c.7806-8_7806-1ins. The latter causes a frameshift and creates a truncated protein, whilst the other two splicing variants resulted in shorter forms of the protein.

CONCLUSIONS

The identified BRCA2 c.7806-9T > G [Genbank: DQ889340] was found to be pathogenic, based on aberrant splicing events resulting in the formation of truncated protein products. Thus, better understanding and classification of BRCA variants as neutral or disease causing has important implications for genetic counseling so that appropriate management can be given.

Genetic polymorphism of cytochrome P450 2C19 in healthy Malaysian subjects

AIMS

Impaired S-mephenytoin 4'-hydroxylation is a well-described genetic polymorphism affecting drug metabolism in humans. Although ethnic differences in its distribution of polymorphism has been described, it is not known whether there is an ethnic heterogeneity of the structure and expression of the CYP2C19 enzyme in the Malaysian population.

METHODS

Study subjects were 142 healthy, unrelated Malaysians aged 18-29 years. Baseline omeprazole and 2-h postingestion omeprazole and 5'-hydroxyomeprazole concentrations were measured for CYP2C19 phenotype determination. Identification of CYP2C19 genotypes was performed with the use of polymerase chain reaction.

RESULTS

Phenotyping of CYP2C19 revealed that the prevalence of poor metabolizers (PMs) in the Malaysian population was 14.1%, whereas prevalence of PMs in genotyping was 12.6%. The PM genotypic prevalence rate was 5.6% in Malays, 19.1% in Chinese and 10.0% in Indian subjects. There were significant differences in PM genotypic prevalence rates among the three primary ethnic groups (P < or = 0.05).

CONCLUSIONS

Phenotyping and genotyping revealed significant differences in the prevalence rates among the three ethnic groups in Malaysia, with Chinese recording highest prevalence.

Unique immunogenicity of hepatitis B virus DNA vaccine presented by live-attenuated Salmonella typhimurium

A novel vaccine for hepatitis B virus (HBV) was designed by putting a naked DNA vaccine carrying hepatitis B surface antigen (HBsAg) into live-attenuated Salmonella typhimurium. Mucosal immunization by the oral route in mice showed significantly stronger cytotoxic T lymphocyte (CTL) response than recombinant HBsAg vaccination (P < 0.01 at an effector:target ratio of 100:1), while comparable to intramuscular naked DNA immunization at all effector:target ratios. Contrary to previous reports on naked DNA vaccines given intramuscularly, the IgG antibody response induced by the mucosal DNA vaccine is relatively weak when compared to recombinant HBsAg vaccine (P < 0.001 at day 21). These findings are supported by a high interferon-gamma but a low interleukin-4 level detected in the supernatant of splenic cell cultures obtained from mucosally immunized mice. As distinct to recombinant HBsAg vaccine which is effective for protection, oral mucosal DNA vaccine should be considered as a candidate for therapeutic immunization in chronic HBV infection, donor immunization before adoptive transfer of HBV-specific CTL to HBsAg positive bone marrow transplant recipients, and immunization of non-responders to recombinant HBsAg vaccine. This strongly cellular and relatively absent humoral response may make this vaccine a better candidate as a therapeutic vaccine for chronic HBV carriers than naked DNA vaccines, as the humoral response is relatively less important for the clearance of HBV from hepatocytes, but its presence may lead to side effects such as serum sickness and immune complex deposition in chronic HBV carriers.

Enhancement by ampicillin of antibody responses induced by a protein antigen and a DNA vaccine carried by live-attenuated Salmonella enterica serovar Typhi

Live-attenuated Salmonella species are effective carriers of microbial antigens and DNA vaccines. In a mouse model, the immunoglobulin M (IgM) and total antibody levels directed toward the lipopolysaccharide of Salmonella enterica serovar Typhi were significantly enhanced at day 21 after oral immunization with live-attenuated serovar Typhi (strain Ty21a) when ampicillin was concomitantly administered (P < 0.05 and P < 0.005, respectively). The heat-killed Ty21a-stimulated lymphocyte proliferation indices for the ampicillin group at day 21 were significantly higher than those for the normal saline (NS) group (P < 0.005, P < 0.001, and P < 0.01) for all three doses of antigen (10(4), 10(5), and 10(6) heat-killed Ty21a per well, respectively). The 50% lethal doses for mice from the ampicillin and NS groups immunized with Ty21a with pBR322 after wild-type serovar Typhi challenge on day 24 were 3.4 x 10(7) and 5.0 x 10(6) CFU, respectively. The fecal bacterial counts for the ampicillin group at days 1, 3, and 5 were significantly lower than those for the NS group (P < 0.01, P < 0.01, and P < 0.05, respectively), and there was a trend toward recovery of Ty21a in a larger number of mice from the ampicillin group than from the NS group. Furthermore, the IgG2a levels directed toward tetanus toxoid were significantly enhanced at days 7 and 21 after oral immunization with Ty21a that carried the fragment c of tetanus toxoid when ampicillin was concomitantly administered (P < 0.05 and P < 0.005, respectively), and the IgM and total hepatitis B surface antibody levels were significantly enhanced at days 7 (P < 0.005 and P < 0.05, respectively) and 21 (P < 0.01 and P < 0.05, respectively) after oral immunization with Ty21a that carried the DNA vaccine that encodes hepatitis B surface antigen when ampicillin was concomitantly administered. The present observation may improve the efficacy of the protein antigens and DNA vaccines carried in live-attenuated bacteria, and further experiments should be carried out to determine the best antibiotics and dosage regimen to be used, as well as the best carrier system for individual protein antigens and DNA vaccines.

Antibiotics modulate vaccine-induced humoral immune response

The effects of antibiotics on the antigen-specific humoral immune response are not known. Macrolides, tetracyclines, and beta-lactams are commonly prescribed antibiotics. The first two are known to have immunomodulatory activities. The effects of clarithromycin, doxycycline, and ampicillin on the primary and secondary antibody responses to tetanus toxoid, a pneumococcal polysaccharide vaccine, a hepatitis B virus surface antigen (HBsAg) vaccine, and live attenuated Salmonella typhi (Ty21a) were investigated using a mouse model. For the mice receiving the tetanus toxoid, the immunoglobulin M (IgM) level of the clarithromycin group at day 7 was significantly lower than the corresponding antibody level of the normal saline (NS) group. For the mice receiving the pneumococcal polysaccharide vaccine, the total antibody and IgM levels of the clarithromycin group and the IgM level of the doxycycline group at day 7 were significantly lower than the corresponding antibody levels of the ampicillin and NS groups. For the mice receiving the HBsAg vaccine, the IgM level of the doxycycline group at day 7 was significantly lower than the corresponding antibody levels of the clarithromycin and NS groups, while the IgM level of the clarithromycin group at day 28 was significantly lower than the corresponding antibody levels of the doxycycline, ampicillin, and NS groups. For the mice receiving all three vaccines, there were no statistically significant differences between any of the antibody levels of the ampicillin group and the corresponding antibody levels of the NS group. For the mice receiving Ty21a, the total antibody levels of the ampicillin group at days 7 and 21 were significantly higher than the corresponding antibody levels of the NS group. Moreover, the IgM levels of the clarithromycin, doxycycline, and ampicillin groups at days 7 and 21 were significantly higher than the corresponding antibody levels of the NS group. Furthermore, the total antibody level of the ampicillin group at day 21 was significantly higher than the corresponding antibody level of the doxycycline group. For all four vaccines, there were no statistically significant differences among the serum levels of interleukin-10 and gamma interferon for the mice treated with the various antibiotics. We conclude that clarithromycin and doxycycline, but not ampicillin, suppress the antibody responses of mice to T-cell-dependent and T-cell-independent antigens, whereas all three antibiotics enhance the antibody response to live attenuated mucosal bacterial vaccines.

Comparison of two automated DNA amplification systems with a manual one-tube nested PCR assay for diagnosis of pulmonary tuberculosis

Eighty-four specimens of respiratory secretions culture positive for mycobacteria (70 positive for Mycobacterium tuberculosis and 14 positive for nontuberculous mycobacteria) and 120 culture-negative specimens were evaluated by three DNA amplification techniques: a manual in-house single-tube nested PCR (nPCR) and two commercial automated assays (the Cobas Amplicor System [aPCR-h] from Roche Diagnostic Systems and the Abbott LCx Probe System [aLCx-p] from Abbott Laboratories). The overall diagnostic sensitivities of the nPCR, aPCR-h, and aLCx-p were 77.1, 84.3, and 77.1%, respectively, and the sensitivities were 57.9, 57.9, and 36.8%, respectively, for smear-negative specimens. Specimens culture positive for nontuberculous mycobacteria were negative by all three assays. Eight culture-negative specimens which were positive by one or more assays had previously been documented by culture to be positive for M. tuberculosis and were taken from patients who were treated with antituberculosis agents. Retesting of specimens negative by one assay by the other two assays revealed that each test had its unique group of negative specimens. When considering the DNA extraction and amplification steps of these assays separately, it was found that extracts from aPCR-h and aLCx-p were compatible with nPCR amplication, while the two automated assays could only amplify extracts processed with their own reagents. Limiting dilution analysis revealed that the order of analytical sensitivity was nPCR, followed by aLCx-p and then aPCR-h. Comparison of the work flow of each assay revealed that although the aPCR-h demands the least specimen handling, the turnaround time of aLCx-p is the most favorable.

Cloning and identification of amino acid residues of human phospholipase C delta 1 essential for catalysis

In vitro single point mutagenesis, inositol phospholipid hydrolysis, and substrate protection experiments were used to identify catalytic residues of human phosphatidylinositide-specific phospholipase C delta 1 (PLC delta 1) isolated from a human aorta cDNA library. Invariant amino acid residues containing a functional side chain in the highly conserved X region were changed by in vitro mutagenesis. Most of the mutant enzymes were still able to hydrolyze inositol phospholipid with activity ranging from 10 to 100% of levels in the wild type enzyme. Exceptions were mutants with the conversion of Arg338 to Leu (R338L), Glu341 to Gly (E341G), or His356 to Leu (H356L), which made the enzyme severely defective in hydrolyzing inositol phospholipid. Phospholipid vesicle binding experiments showed that these three cleavage-defective mutant forms of PLC delta 1 could specifically bind to phosphatidylinositol 4,5-bisphosphate (PIP2) with an affinity similar to that of wild type enzyme. Western blotting analysis of trypsin-treated enzyme-PIP2 complexes revealed that a 67-kDa major protein fragment survived trypsin digestion if the wild type enzyme, E341G, or H356L mutant PLC delta 1 was preincubated with 7.5 microM PIP2, whereas if it was preincubated with 80 microM PIP2, the size of major protein surviving was comparable to that of intact enzyme. However, mutant enzyme R338L was not protected from trypsin degradation by PIP2 binding. These observations suggest that PLC delta 1 can recognize PIP2 through a high affinity and a low affinity binding site and that residues Glu341 and His356 are not involved in either high affinity or low affinity PIP2 binding but rather are essential for the Ca(2+)-dependent cleavage activity of PLC.

Effect of pH on in vitro ruminal conversion of L-tryptophan to 3-methylindole and indole

Three in vitro experiments were conducted to determine the effects of pH on ruminal conversion of L-tryptophan (TRP) to 3-methylindole (3-MI) and indole (IND). Experiment 1 involved 2 closed-system incubations, each with triplicate replications of buffered ruminal fluid at initial pH of 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, and 8.0. Highest molar conversions of TRP to 3-MI were 61.5 +/- 2.7% and 64.3 +/- 0.8% at initial pH treatments of 7.5 and 7.0 (final pH 7.3 and 6.9) for the 2 incubations, respectively. Experiment 2 used duplicate continuous cultures at each of 4 pH treatments. Following a common 5-day pretreatment period, effluent pH averaged 5.6, 6.1, 6.5, and 6.9 for the respective treatments. Data for 4 subsequent 5-day time periods showed production of 3-MI was affected by pH treatment (P less than 0.01), time (P greater than 0.01), and treatment X time (P less than 0.01); conversion of TRP to 3-MI reached 78% at pH 6.9 and decreased to less than 1% at pH 5.6. Production of IND was not related to pH treatment (P greater than 0.10). Total moles of volatile fatty acid (VFA) carbon produced showed a pH treatment X time interaction (P less than 0.01) which reflected a trend toward decreasing VFA production at lower pH and increasing VFA production at higher pH. Experiment 3 consisted of 2 pH treatments with additional continuous culture fermenters.(ABSTRACT TRUNCATED AT 250 WORDS)