The chromatin landscape of healthy and injured cell types in the human kidney

There is a need to define regions of gene activation or repression that control human kidney cells in states of health, injury, and repair to understand the molecular pathogenesis of kidney disease and design therapeutic strategies. Comprehensive integration of gene expression with epigenetic features that define regulatory elements remains a significant challenge. We measure dual single nucleus RNA expression and chromatin accessibility, DNA methylation, and H3K27ac, H3K4me1, H3K4me3, and H3K27me3 histone modifications to decipher the chromatin landscape and gene regulation of the kidney in reference and adaptive injury states. We establish a spatially-anchored epigenomic atlas to define the kidney's active, silent, and regulatory accessible chromatin regions across the genome. Using this atlas, we note distinct control of adaptive injury in different epithelial cell types. A proximal tubule cell transcription factor network of ELF3, KLF6, and KLF10 regulates the transition between health and injury, while in thick ascending limb cells this transition is regulated by NR2F1. Further, combined perturbation of ELF3, KLF6, and KLF10 distinguishes two adaptive proximal tubular cell subtypes, one of which manifested a repair trajectory after knockout. This atlas will serve as a foundation to facilitate targeted cell-specific therapeutics by reprogramming gene regulatory networks.

C-peptide and metabolic outcomes in trials of disease modifying therapy in new-onset type 1 diabetes: an individual participant meta-analysis

BACKGROUND

Metabolic outcomes in type 1 diabetes remain suboptimal. Disease modifying therapy to prevent β-cell loss presents an alternative treatment framework but the effect on metabolic outcomes is unclear. We, therefore, aimed to define the relationship between insulin C-peptide as a marker of β-cell function and metabolic outcomes in new-onset type 1 diabetes.

METHODS

21 trials of disease-modifying interventions within 100 days of type 1 diabetes diagnosis comprising 1315 adults (ie, those 18 years and older) and 1396 children (ie, those younger than 18 years) were combined. Endpoints assessed were stimulated area under the curve C-peptide, HbA1c, insulin use, hypoglycaemic events, and composite scores (such as insulin dose adjusted A1c, total daily insulin, U/kg per day, and BETA-2 score). Positive studies were defined as those meeting their primary endpoint. Differences in outcomes between active and control groups were assessed using the Wilcoxon rank test.

FINDINGS

6 months after treatment, a 24·8% greater C-peptide preservation in positive studies was associated with a 0·55% lower HbA1c (p<0·0001), with differences being detectable as early as 3 months. Cross-sectional analysis, combining positive and negative studies, was consistent with this proportionality: a 55% improvement in C-peptide preservation was associated with 0·64% lower HbA1c (p<0·0001). Higher initial C-peptide levels and greater preservation were associated with greater improvement in HbA1c. For HbA1c, IDAAC, and BETA-2 score, sample size predictions indicated that 2-3 times as many participants per group would be required to show a difference at 6 months as compared with C-peptide. Detecting a reduction in hypoglycaemia was affected by reporting methods.

INTERPRETATION

Interventions that preserve β-cell function are effective at improving metabolic outcomes in new-onset type 1 diabetes, confirming their potential as adjuncts to insulin. We have shown that improvements in HbA1c are directly proportional to the degree of C-peptide preservation, quantifying this relationship, and supporting the use of C-peptides as a surrogate endpoint in clinical trials.

FUNDING

JDRF and Diabetes UK.

The chromatin landscape of healthy and injured cell types in the human kidney

There is a need to define regions of gene activation or repression that control human kidney cells in states of health, injury, and repair to understand the molecular pathogenesis of kidney disease and design therapeutic strategies. However, comprehensive integration of gene expression with epigenetic features that define regulatory elements remains a significant challenge. We measured dual single nucleus RNA expression and chromatin accessibility, DNA methylation, and H3K27ac, H3K4me1, H3K4me3, and H3K27me3 histone modifications to decipher the chromatin landscape and gene regulation of the kidney in reference and adaptive injury states. We established a comprehensive and spatially-anchored epigenomic atlas to define the kidney's active, silent, and regulatory accessible chromatin regions across the genome. Using this atlas, we noted distinct control of adaptive injury in different epithelial cell types. A proximal tubule cell transcription factor network of ELF3 , KLF6 , and KLF10 regulated the transition between health and injury, while in thick ascending limb cells this transition was regulated by NR2F1 . Further, combined perturbation of ELF3 , KLF6 , and KLF10 distinguished two adaptive proximal tubular cell subtypes, one of which manifested a repair trajectory after knockout. This atlas will serve as a foundation to facilitate targeted cell-specific therapeutics by reprogramming gene regulatory networks.

Alterations in Protein Translation and Carboxylic Acid Catabolic Processes in Diabetic Kidney Disease

Diabetic kidney disease (DKD) remains the leading cause of end-stage kidney disease despite decades of study. Alterations in the glomerulus and kidney tubules both contribute to the pathogenesis of DKD although the majority of investigative efforts have focused on the glomerulus. We sought to examine the differential expression signature of human DKD in the glomerulus and proximal tubule and corroborate our findings in the db/db mouse model of diabetes. A transcriptogram network analysis of RNAseq data from laser microdissected (LMD) human glomerulus and proximal tubule of DKD and reference nephrectomy samples revealed enriched pathways including rhodopsin-like receptors, olfactory signaling, and ribosome (protein translation) in the proximal tubule of human DKD biopsy samples. The translation pathway was also enriched in the glomerulus. Increased translation in diabetic kidneys was validated using polyribosomal profiling in the db/db mouse model of diabetes. Using single nuclear RNA sequencing (snRNAseq) of kidneys from db/db mice, we prioritized additional pathways identified in human DKD. The top overlapping pathway identified in the murine snRNAseq proximal tubule clusters and the human LMD proximal tubule compartment was carboxylic acid catabolism. Using ultra-performance liquid chromatography–mass spectrometry, the fatty acid catabolism pathway was also found to be dysregulated in the db/db mouse model. The Acetyl-CoA metabolite was down-regulated in db/db mice, aligning with the human differential expression of the genes ACOX1 and ACACB. In summary, our findings demonstrate that proximal tubular alterations in protein translation and carboxylic acid catabolism are key features in both human and murine DKD.

A positive relationship between functional redundancy and temperature in Cenozoic marine ecosystems

The long-term effects of climate change on biodiversity and biogeographic patterns are uncertain. There are known relationships between geographic area and both the number of species and the number of ecological functional groups-termed the species-area relationship and the functional diversity-area relationship, respectively. We show that there is a positive relationship between the number of species in an area, the number of ecological functional groups, and oceanic temperature in the shallow-marine fossil record of New Zealand over a time span of ~40 million years. One implication of this relationship is that functional redundancy increases with temperature. This reveals a long-lived and persistent association between the spatial structuring of biodiversity, the temperature-dependence of functional redundancy, and shallow-marine biodiversity in mid-latitudes.

Integration of spatial and single-cell transcriptomics localizes epithelial cell-immune cross-talk in kidney injury

Single-cell sequencing studies have characterized the transcriptomic signature of cell types within the kidney. However, the spatial distribution of acute kidney injury (AKI) is regional and affects cells heterogeneously. We first optimized coordination of spatial transcriptomics and single-nuclear sequencing data sets, mapping 30 dominant cell types to a human nephrectomy. The predicted cell-type spots corresponded with the underlying histopathology. To study the implications of AKI on transcript expression, we then characterized the spatial transcriptomic signature of 2 murine AKI models: ischemia/reperfusion injury (IRI) and cecal ligation puncture (CLP). Localized regions of reduced overall expression were associated with injury pathways. Using single-cell sequencing, we deconvoluted the signature of each spatial transcriptomic spot, identifying patterns of colocalization between immune and epithelial cells. Neutrophils infiltrated the renal medulla in the ischemia model. Atf3 was identified as a chemotactic factor in S3 proximal tubules. In the CLP model, infiltrating macrophages dominated the outer cortical signature, and Mdk was identified as a corresponding chemotactic factor. The regional distribution of these immune cells was validated with multiplexed CO-Detection by indEXing (CODEX) immunofluorescence. Spatial transcriptomic sequencing complemented single-cell sequencing by uncovering mechanisms driving immune cell infiltration and detection of relevant cell subpopulations.

Observation of a prethermal discrete time crystal

Extending the framework of statistical physics to the nonequilibrium setting has led to the discovery of previously unidentified phases of matter, often catalyzed by periodic driving. However, preventing the runaway heating that is associated with driving a strongly interacting quantum system remains a challenge in the investigation of these newly discovered phases. In this work, we utilize a trapped-ion quantum simulator to observe the signatures of a nonequilibrium driven phase without disorder-the prethermal discrete time crystal. Here, the heating problem is circumvented not by disorder-induced many-body localization, but rather by high-frequency driving, which leads to an expansive time window where nonequilibrium phases can emerge. Floquet prethermalization is thus presented as a general strategy for creating, stabilizing, and studying intrinsically out-of-equilibrium phases of matter.

Clinical, histopathologic and molecular features of idiopathic and diabetic nodular mesangial sclerosis in humans

BACKGROUND

Idiopathic nodular mesangial sclerosis, also called idiopathic nodular glomerulosclerosis (ING), is a rare clinical entity with an unclear pathogenesis. The hallmark of this disease is the presence of nodular mesangial sclerosis on histology without clinical evidence of diabetes mellitus or other predisposing diagnoses. To achieve insights into its pathogenesis, we queried the clinical, histopathologic and transcriptomic features of ING and nodular diabetic nephropathy (DN).

METHODS

All renal biopsy reports accessioned at Indiana University Health from 2001 to 2016 were reviewed to identify 48 ING cases. Clinical and histopathologic features were compared between individuals with ING and DN (n = 751). Glomeruli of ING (n = 5), DN (n = 18) and reference (REF) nephrectomy (n = 9) samples were isolated by laser microdissection and RNA was sequenced. Immunohistochemistry of proline-rich 36 (PRR36) protein was performed.

RESULTS

ING subjects were frequently hypertensive (95.8%) with a smoking history (66.7%). ING subjects were older, had lower proteinuria and had less hyaline arteriolosclerosis than DN subjects. Butanoate metabolism was an enriched pathway in ING samples compared with either REF or DN samples. The top differentially expressed gene, PRR36, had increased expression in glomeruli 248-fold [false discovery rate (FDR) P = 5.93 × 10-6] compared with the REF and increased 109-fold (FDR P = 1.85 × 10-6) compared with DN samples. Immunohistochemistry revealed a reduced proportion of cells with perinuclear reaction in ING samples as compared to DN.

CONCLUSIONS

Despite similar clinical and histopathologic characteristics in ING and DN, the uncovered transcriptomic signature suggests that ING has distinct molecular features from nodular DN. Further study is warranted to understand these relationships.

Molecular characterization of the human kidney interstitium in health and disease

The gene expression signature of the human kidney interstitium is incompletely understood. The cortical interstitium (excluding tubules, glomeruli, and vessels) in reference nephrectomies (N = 9) and diabetic kidney biopsy specimens (N = 6) was laser microdissected (LMD) and sequenced. Samples underwent RNA sequencing. Gene signatures were deconvolved using single nuclear RNA sequencing (snRNAseq) data derived from overlapping specimens. Interstitial LMD transcriptomics uncovered previously unidentified markers including KISS1, validated with in situ hybridization. LMD transcriptomics and snRNAseq revealed strong correlation of gene expression within corresponding kidney regions. Relevant enriched interstitial pathways included G-protein coupled receptor. binding and collagen biosynthesis. The diabetic interstitium was enriched for extracellular matrix organization and small-molecule catabolism. Cell type markers with unchanged expression (NOTCH3, EGFR, and HEG1) and those down-regulated in diabetic nephropathy (MYH11, LUM, and CCDC3) were identified. LMD transcriptomics complements snRNAseq; together, they facilitate mapping of interstitial marker genes to aid interpretation of pathophysiology in precision medicine studies.

The orchestrated cellular and molecular responses of the kidney to endotoxin define a precise sepsis timeline

Sepsis is a dynamic state that progresses at variable rates and has life-threatening consequences. Staging patients along the sepsis timeline requires a thorough knowledge of the evolution of cellular and molecular events at the tissue level. Here, we investigated the kidney, an organ central to the pathophysiology of sepsis. Single-cell RNA-sequencing in a murine endotoxemia model revealed the involvement of various cell populations to be temporally organized and highly orchestrated. Endothelial and stromal cells were the first responders. At later time points, epithelial cells upregulated immune-related pathways while concomitantly downregulating physiological functions such as solute homeostasis. Sixteen hours after endotoxin, there was global cell–cell communication failure and organ shutdown. Despite this apparent organ paralysis, upstream regulatory analysis showed significant activity in pathways involved in healing and recovery. This rigorous spatial and temporal definition of murine endotoxemia will uncover precise biomarkers and targets that can help stage and treat human sepsis.

Multiple reaction monitoring profiling as an analytical strategy to investigate lipids in extracellular vesicles

Extracellular vesicles (EVs) convey information used in cell-to-cell interactions. Lipid analysis of EVs remains challenging because of small sample amounts available. Lipid discovery using traditional mass spectrometry platforms based on liquid chromatography and high mass resolution typically employs milligram sample amounts. We report a simple workflow for lipid profiling of EVs based on multiple reaction monitoring (MRM) profiling that uses microgram amounts of sample. After liquid-liquid extraction, individual EV samples were injected directly into the electrospray ionization (ESI) ion source at low flow rates (10 μl/min) and screened for 197 MRM transitions chosen to be a characteristic of several classes of lipids. This choice was based on a discovery experiment, which applied 1,419 MRMs associated with multiple lipid classes to a representative pooled sample. EVs isolated from 12 samples of human lymphocytes and 16 replicates from six different rat cells lines contained an estimated amount of total lipids of 326 to 805 μg. Samples showed profiles that included phosphatidylcholine (PC), sphingomyelin (SM), cholesteryl ester (CE), and ceramide (Cer) lipids, as well as acylcarnitines. The lipid profiles of human lymphocyte EVs were distinguishable using principal component and cluster analysis in terms of prior antibody and drug exposure. Lipid profiles of rat cell lines EV's were distinguishable by their tissue of origin.

Genotype-Guided Hydralazine Therapy

BACKGROUND

Despite its approval in 1953, hydralazine hydrochloride continues to be used in the management of resistant hypertension, a condition frequently managed by nephrologists and other clinicians. Hydralazine hydrochloride undergoes metabolism by the N-acetyltransferase 2 (NAT2) enzyme. NAT2 is highly polymorphic as approximately 50% of the general population are slow acetylators. In this review, we first evaluate the link between NAT2 genotype and phenotype. We then assess the evidence available for genotype-guided therapy of hydralazine, specifically addressing associations of NAT2 acetylator status with hydralazine pharmacokinetics, antihypertensive efficacy, and toxicity.

SUMMARY

There is a critical need to use hydralazine in some patients with resistant hypertension. Available evidence supports a significant link between genotype and NAT2 enzyme activity as 29 studies were identified with an overall concordance between genotype and phenotype of 92%. The literature also supports an association between acetylator status and hydralazine concentration, as fourteen of fifteen identified studies revealed significant relationships with a consistent direction of effect. Although fewer studies are available to directly link acetylator status with hydralazine antihypertensive efficacy, the evidence from this smaller set of studies is significant in 7 of 9 studies identified. Finally, 5 studies were identified which support the association of acetylator status with hydralazine-induced lupus. Clinicians should maintain vigilance when prescribing maximum doses of hydralazine. Key Messages: NAT2 slow acetylator status predicts increased hydralazine levels, which may lead to increased efficacy and adverse effects. Caution should be exercised in slow acetylators with total daily hydralazine doses of 200 mg or more. Fast acetylators are at risk for inefficacy at lower doses of hydralazine. With appropriate guidance on the usage of NAT2 genotype, clinicians can adopt a personalized approach to hydralazine dosing and prescription, enabling more efficient and safe treatment of resistant hypertension.

Interindividual Variability in Lymphocyte Stimulation and Transcriptomic Response Predicts Mycophenolic Acid Sensitivity in Healthy Volunteers

Mycophenolic acid (MPA) is an immunosuppressant commonly used to prevent renal transplant rejection and treat glomerulonephritis. MPA inhibits IMPDH2 within stimulated lymphocytes, reducing guanosine synthesis. Despite the widespread use of MPA, interindividual variability in response remains with rates of allograft rejection up to 15% and approximately half of individuals fail to achieve complete remission to lupus nephritis. We sought to identify contributors to interindividual variability in MPA response, hypothesizing that the HPRT1 salvage guanosine synthesis contributes to variability. MPA sensitivity was measured in 40 healthy individuals using an ex vivo lymphocyte viability assay. Measurement of candidate gene expression (n ± 40) and single‐cell RNA‐sequencing (n ± 6) in lymphocytes was performed at baseline, poststimulation, and post‐MPA treatment. After stimulation, HPRT1 expression was 2.1‐fold higher in resistant individuals compared with sensitive individuals (P ± 0.049). Knockdown of HPRT1 increased MPA sensitivity (12%; P ± 0.003), consistent with higher expression levels in resistant individuals. Sensitive individuals had higher IMPDH2 expression and 132% greater stimulation. In lymphocyte subpopulations, differentially expressed genes between sensitive and resistant individuals included KLF2 and LTB. Knockdown of KLF2 and LTB aligned with the predicted direction of effect on proliferation. In sensitive individuals, more frequent receptor‐ligand interactions were observed after stimulation (P ± 0.0004), but fewer interactions remained after MPA treatment (P ± 0.0014). These data identify a polygenic transcriptomic signature in lymphocyte subpopulations predictive of MPA response. The degree of lymphocyte stimulation, HPRT1, KLF2, and LTB expression may serve as markers of MPA efficacy.

Implementation of a Renal Precision Medicine Program: Clinician Attitudes and Acceptance

A precision health initiative was implemented across a multi-hospital health system, wherein a panel of genetic variants was tested and utilized in the clinical care of chronic kidney disease (CKD) patients. Pharmacogenomic predictors of antihypertensive response and genomic predictors of CKD were provided to clinicians caring for nephrology patients. To assess clinician knowledge, attitudes, and willingness to act on genetic testing results, a Likert-scale survey was sent to and self-administered by these nephrology providers (N = 76). Most respondents agreed that utilizing pharmacogenomic-guided antihypertensive prescribing is valuable (4.0 ± 0.7 on a scale of 1 to 5, where 5 indicates strong agreement). However, the respondents also expressed reluctance to use genetic testing for CKD risk stratification due to a perceived lack of supporting evidence (3.2 ± 0.9). Exploratory sub-group analyses associated this reluctance with negative responses to both knowledge and attitude discipline questions, thus suggesting reduced exposure to and comfort with genetic information. Given the evolving nature of genomic implementation in clinical care, further education is warranted to help overcome these perception barriers.

Influence of Uridine Diphosphate Glucuronosyltransferase Family 1 Member A1 and Solute Carrier Organic Anion Transporter Family 1 Member B1 Polymorphisms and Efavirenz on Bilirubin Disposition in Healthy Volunteers

Chronic administration of efavirenz is associated with decreased serum bilirubin levels, probably through induction of UGT1A1 We assessed the impact of efavirenz monotherapy and UGT1A1 phenotypes on total, conjugated, and unconjugated serum bilirubin levels in healthy volunteers. Healthy volunteers were enrolled into a clinical study designed to address efavirenz pharmacokinetics, drug interactions, and pharmacogenetics. Volunteers received multiple oral doses (600 mg/day for 17 days) of efavirenz. Serum bilirubin levels were obtained at study entry and 1 week after completion of the study. DNA genotyping was performed for UGT1A1 [*80 (C>T), *6 (G>A), *28 (TA₇), *36 (TA₅), and *37 (TA₈)] and for SLCO1B1 [*5 (521T>C) and *1b (388A>G] variants. Diplotype predicted phenotypes were classified as normal, intermediate, and slow metabolizers. Compared with bilirubin levels at screening, treatment with efavirenz significantly reduced total, conjugated, and unconjugated bilirubin. After stratification by UGT1A1 phenotypes, there was a significant decrease in total bilirubin among all phenotypes, conjugated bilirubin among intermediate metabolizers, and unconjugated bilirubin among normal and intermediate metabolizers. The data also show that UGT1A1 genotype predicts serum bilirubin levels at baseline, but this relationship is lost after efavirenz treatment. SLCO1B1 genotypes did not predict bilirubin levels at baseline or after efavirenz treatment. Our data suggest that efavirenz may alter bilirubin disposition mainly through induction of UGT1A1 metabolism and efflux through multidrug resistance-associated protein 2. SIGNIFICANCE STATEMENT: Efavirenz likely alters the pharmacokinetics of coadministered drugs, potentially causing lack of efficacy or increased adverse effects, as well as the disposition of endogenous compounds relevant in homeostasis through upregulation of UGT1A1 and multidrug resistance-associated protein 2. Measurement of unconjugated and conjugated bilirubin during new drug development may provide mechanistic understanding regarding enzyme and transporters modulated by the new drug.

Common latitudinal gradients in functional richness and functional evenness across marine and terrestrial systems

Functional diversity is an important aspect of biodiversity, but its relationship to species diversity in time and space is poorly understood. Here we compare spatial patterns of functional and taxonomic diversity across marine and terrestrial systems to identify commonalities in their respective ecological and evolutionary drivers. We placed species-level ecological traits into comparable multi-dimensional frameworks for two model systems, marine bivalves and terrestrial birds, and used global species-occurrence data to examine the distribution of functional diversity with latitude and longitude. In both systems, tropical faunas show high total functional richness (FR) but low functional evenness (FE) (i.e. the tropics contain a highly skewed distribution of species among functional groups). Functional groups that persist toward the poles become more uniform in species richness, such that FR declines and FE rises with latitude in both systems. Temperate assemblages are more functionally even than tropical assemblages subsampled to temperate levels of species richness, suggesting that high species richness in the tropics reflects a high degree of ecological specialization within a few functional groups and/or factors that favour high recent speciation or reduced extinction rates in those groups.

Extinction risk in extant marine species integrating palaeontological and biodistributional data

Extinction risk assessments of marine invertebrate species remain scarce, which hinders effective management of marine biodiversity in the face of anthropogenic impacts. To help close this information gap, in this paper we provide a metric of relative extinction risk that combines palaeontological data, in the form of extinction rates calculated from the fossil record, with two known correlates of risk in the modern day: geographical range size and realized thermal niche. We test the performance of this metric-Palaeontological Extinction Risk In Lineages (PERIL)-using survivorship analyses of Pliocene bivalve faunas from California and New Zealand, and then use it to identify present-day hotspots of extinction vulnerability for extant shallow-marine Bivalvia. Areas of the ocean where concentrations of bivalve species with higher PERIL scores overlap with high levels of climatic or anthropogenic stressors should be considered of most immediate concern for both conservation and management.

Improving the Patency of Jugular Vein Catheters in Sprague-Dawley Rats by Using an Antiseptic Nitrocellulose Coating

Preclinical studies in animals often require frequent blood sampling over prolonged periods. A preferred method in rats is the implantation of a polyurethane catheter into the jugular vein, with heparinized glycerol as a lock solution. However, analysis of various biologic compounds (for example, microRNA) precludes the use of heparin. We used sodium citrate as an alternative to heparin but observed more frequent loss of catheter patency. We hypothesized that this effect was due to evaporation of lock solution at the exteriorized portion of the catheter, subsequent blood infiltration into the catheter, and ultimately clot formation within the catheter. We therefore tested evaporation and its variables in vitro by using 5 common catheter materials. We used the migration of dye into vertically anchored catheters as a measure of lock displacement due to evaporation. Exposure to dry room-temperature air was sufficient to cause dye migration against gravity, whereas a humid environment and adding glycerol to the lock solution mitigated this effect, thus confirming loss of the lock solution from the catheter by evaporation. We tested 4 catheter treatments for the ability to reduce lock evaporation. Results were validated in vivo by using male Sprague-Dawley rats (n = 12) implanted with polyurethane jugular vein catheters and randomized to receive a nitrocellulose-based coating on the exteriorized portion of the catheter. Coating the catheters significantly improved patency, as indicated by a Kaplan-Meier log-rank hazard ratio greater than 5 in untreated catheters. We here demonstrate that a simple nitrocellulose coating reduces evaporation from and thus prolongs the patency of polyurethane catheters in rats.

PASSPORT-seq: A Novel High-Throughput Bioassay to Functionally Test Polymorphisms in Micro-RNA Target Sites

Next-generation sequencing (NGS) studies have identified large numbers of genetic variants that are predicted to alter miRNA–mRNA interactions. We developed a novel high-throughput bioassay, PASSPORT-seq, that can functionally test in parallel 100s of these variants in miRNA binding sites (mirSNPs). The results are highly reproducible across both technical and biological replicates. The utility of the bioassay was demonstrated by testing 100 mirSNPs in HEK293, HepG2, and HeLa cells. The results of several of the variants were validated in all three cell lines using traditional individual luciferase assays. Fifty-five mirSNPs were functional in at least one of three cell lines (FDR ≤ 0.05); 11, 36, and 27 of them were functional in HEK293, HepG2, and HeLa cells, respectively. Only four of the variants were functional in all three cell lines, which demonstrates the cell-type specific effects of mirSNPs and the importance of testing the mirSNPs in multiple cell lines. Using PASSPORT-seq, we functionally tested 111 variants in the 3′ UTR of 17 pharmacogenes that are predicted to alter miRNA regulation. Thirty-three of the variants tested were functional in at least one cell line.

Cardiovascular risk factors in women with primary Sjögren's syndrome: United Kingdom primary Sjögren's syndrome registry results

Objective

To determine the prevalence of traditional cardiovascular risk factors using established definitions in a large cohort of clinically well-characterized primary Sjögren's syndrome (SS) patients and to compare them to healthy controls.

Methods

Data on cardiovascular risk factors in primary SS patients and controls were collected prospectively using a standardized pro forma. Cardiovascular risk factors were defined according to established definitions. The prevalence of cardiovascular risk factors in the primary SS group was determined and compared to that in the control group.

Results

Primary SS patients had a higher prevalence of hypertension (28–50% versus 15.5–25.6%; P < 0.01) and hypertriglyceridemia (21% versus 9.5%; P = 0.002) than age- and sex-matched healthy controls. Furthermore, a significant percentage (56%) of hypertensive patients expected to be on antihypertensive treatment according to best practice was not receiving it.

Conclusion

Primary SS patients are more than 2 times more likely to experience hypertension and hypertriglyceridemia than age- and sex-matched healthy controls. Additionally, hypertension is underdiagnosed and suboptimally treated in primary SS.

Assessment of blood clot formation and platelet receptor function ex vivo in patients with primary Sjogren's syndrome

OBJECTIVES

Primary Sjögren's syndrome (pSS) shares clinical features and pathogenetic mechanisms with systemic lupus erythematosus (SLE). SLE is associated with an increased thromboembolic risk; however, it is unclear whether pSS patients are susceptible to thromboembolic diseases. In this study, we examined ex vivo blood clot formation (clot strength, rates of clot formation and lysis) in pSS using thromboelastography (TEG) and platelet aggregation to common agonists using multiple electrode aggregometry (MEA). We also investigated the relationship between TEG/MEA parameters and clinical/laboratory features of pSS.

DESIGN

Case control.

SETTING

Secondary care, single centre.

PARTICIPANTS

34 pSS patients, 11 SLE patients and 13 healthy volunteers (all women) entered and completed the study.

PRIMARY OUTCOMES

TEG and MEA parameters between three subject groups.

SECONDARY OUTCOMES

The relationships between TEG/MEA and clinical/laboratory parameters analysed using bivariate correlation analysis with corrections for multiple testing.

RESULTS

All TEG and MEA parameters were similar for the three subject groups. After corrections for multiple testing, interleukin (IL)-1α and Macrophage inflammatory proteins (MIP)-1α remain correlated inversely with clot strength (r=-0.686, p=0.024 and r=-0.730, p=0.012, respectively) and overall coagulability (r=-0.640, p=0.048 and r=-0.648, p=0.048). Stepwise regression analysis revealed that several cytokines such as MIP-1α, IL-17a, IL-1α and Interferon (IFN)-γ may be key predictors of clot strength and overall coagulability in pSS.

CONCLUSIONS

Clot kinetics and platelet receptor function are normal in pSS. Several cytokines correlate with clot strength and overall coagulability in pSS.

Living longer, staying well: promoting good health for older women

Women are living longer than ever. A woman who is 65 today can, on average, expect to live another 19 years to age 84. Despite recognition of the essential role preventive care and healthy habits play in these later years, older women and their physicians often miss opportunities to promote good health. Medicare, which provides basic health insurance coverage for those 65 and older, does include coverage of many preventive services. But cost-sharing for many covered services -- as well as uncovered services such as prescription drugs -- creates financial hardship for many older women, particularly those living on low incomes. This issue brief, based on a new analysis of The Commonwealth Fund 1998 Survey of Women's Health, provides insight into the gaps in preventive care that currently exist and the disparities in access to care found between lower- and higher-income older women. It also suggests steps that can be taken to improve older women's health and quality of life.

Managed care in three states: experiences of low-income African Americans and Hispanics

This article examines the experiences of low-income, nonelderly Hispanics, African Americans, and whites in managed care (MC), and compares them to their racial/ethnic counterparts enrolled in fee-for-service (FFS) health plans. Survey findings from Florida, Tennessee, and Texas show that MC and FFS enrollees do not differ substantially on most access and satisfaction measures, with a few notable exceptions. When compared with their FFS counterparts, African-American MC enrollees are twice as likely to report problems in obtaining needed care, and Hispanic MC enrollees are nearly twice as likely to rate the extent to which their providers care about them as "fair" or "poor." In contrast, whites in MC are less likely to be without a regular provider than their FFS counterparts, but report greater dissatisfaction with the extent to which providers care about them.

Access to medical care for adolescents: results from the 1997 Commonwealth Fund Survey of the Health of Adolescent Girls

PURPOSE

This study examined the factors associated with access to care among adolescents, including gender, insurance coverage, and having a regular source of health care.

METHODS

Analyses were done on the 1997 Commonwealth Fund Survey of the Health of Adolescent Girls, a nationally representative sample of in-school adolescents in 5th through 12th grade. Access to health care, missing needed care, and whether the adolescent had private time with their provider were assessed. Cochran-Mantel-Haenszel chi-square statistics were computed using SUDAAN.

RESULTS

Nearly a third of the 6748 adolescents surveyed had missed needed care. The most common reason for missing care was not wanting a parent to know (35%). Girls were more likely than boys to miss care (29% vs. 24%). Most adolescents reported using a source of primary health care (92%); girls were more likely than boys to use a physician's office rather than another site (65% vs. 60%). Eleven percent of adolescents reported having no health insurance. Uninsured adolescents were more likely to have missed needed care (46% vs. 25%) [corrected].

CONCLUSIONS

Certain groups of adolescents have less access to health care. Girls have more emotional barriers, such as not wanting parents to know about care, and embarrassment. Adolescents without health insurance are at high risk for missing care because of financial strain. States, insurers, and advocates can influence policies around confidentiality and insurance coverage to address these issues.

Immunochemical assay for recognition of 2-S-glutathionyl acetate, a glutathione conjugate derived from 1,1-dichloroethylene-epoxide

Cytotoxicities induced by 1,1-dichloroethylene (DCE) are ascribed to cytochrome P450-dependent metabolism to an epoxide. Conjugation of the DCE-epoxide with glutathione (GSH) results in the formation of the conjugates 2-S-glutathionyl acetate (GTA) and 2-(S-glutathionyl) acetyl glutathione (GAG); GAG undergoes hydrolysis to form GTA, and thus GTA is a major metabolite of DCE metabolism. Our objective is to develop an antiserum against the chemically synthesized GTA, and for immunization, we have used a hapten that consists of GTA conjugated to bovine serum albumin (BSA) as the carrier protein and glutaraldehyde (GLUT) as a chemical cross-linker. The antisera were raised in rabbits and were characterized by using the following synthesized structural analogs: GTA, glycine-GLUT-BSA (GLY-GLUT-BSA), GTA-GLUT-ovalbumin (GTA-GLUT-OVB), GTA-1-ethyl-3-(3-dimethylaminopropyl) carbodiimide-BSA (GTA-EDC-BSA), TRIS-GLUT-BSA, glutathione-GLUT-BSA (GSH-GLUT-BSA). The enzyme-linked immunosorbent assay (ELISA) and slot immunoblotting were used to characterize the specificity of the antisera. Noncompetitive ELISA experiments showed that the reaction of the antiserum with the antigen was concentration-dependent. In the competitive ELISA, GTA-GLUT-BSA inhibited binding efficiently; in contrast, the unconjugated GTA did not inhibit binding to the antigen. Competitive studies with the other analogs indicated low or minimal reactivities with the antibodies, which were blocked by incubation with GLY-GLUT-BSA. However, there was residual reactivity with the antigen that was not competitively inhibited by either the GTA-EDC-BSA or the GSH-GLUT-BSA conjugates. Slot-blotting experiments confirmed the findings of the ELISA studies and revealed high specificity of the antiserum to detect the hapten. These results demonstrated the successful development of polyclonal antibodies to detect GTA and hence DCE-epoxide.

Women and managed care: satisfaction with provider choice, access to care, plan costs and coverage

This article reports on differences in satisfaction with provider choice, access to care, and plan costs and coverage between women enrolled in fee-for-service and those in managed car plans. It also examines differences in satisfaction, access, and costs and coverage between higher and lower income women and between those in reported fair or poor health and those in excellent or good health, among women in managed care plans. The data for this study are from The Commonwealth Fund's 1994 Managed Care Survey, which included 1,544 women with employer- or union-sponsored insurance in Boston, Los Angeles, and Miami. The study found that women in managed care were less satisfied with provider choice and access to services, but more satisfied with out-of-pocket costs for services and the range of services covered. Both low-income women and those in fair to poor health reported more problems with access barriers than did either higher income women or those in excellent or good health.

Practice satisfaction and experiences of women physicians in an era of managed care

Managed care is dramatically changing the way the nation pays for health care and fueling rapid restructuring of health care delivery. In response, the medical profession is confronting new pressures and major shifts in delivery. At the same time, more women are entering the medical profession and more are in medical practice than ever before. To examine practice satisfaction and concerns of women physicians in the current health care environment, this article analyzes the responses to a national survey of physicians by gender. Women physicians were more likely than men physicians to be in generalist or primary care fields, to be practicing in groups than as solo practitioners, to have practices with a high proportion of managed care patients, and to report dissatisfaction with the amount of time they have to spend with patients and colleagues and with their ability to stay knowledgeable. Further research and more in-depth probing of women's experiences are needed to track experiences over time and to relate practice experiences to quality of patient care.

Bilateral jones fractures in a high school football player

OBJECTIVE

To present a case of a high school football player with bilateral Jones fractures who was treated both conservatively and with acute intramedullary compression screw fixation.

BACKGROUND

Jones fractures tend to heal slowly, have a propensity for reinjury, and a significant number progress to delayed union or nonunion. Because of the time constraints imposed by athletic seasons, there is a need to avoid lengthy periods of immobilization.

DIFFERENTIAL DIAGNOSIS

Tuberosity fracture, metatarsal stress fracture.

TREATMENT

Treatment options include either conservative care or acute intramedullary compression screw fixation. Jones fractures are difficult to treat and can cause prolonged disability.

UNIQUENESS

The athlete was treated conservatively for a delayed union of an old stress fracture. X-rays revealed a sclerotic fracture line with partial union after 6 weeks. The athlete underwent open reduction and internal fixation using an intramedullary screw to obtain compression fixation and a graft to aid healing. Several months later, x-rays showed excellent resolution. One year later, he suffered a similar fracture of the other foot. Because of his history and his desire to return to play, he underwent open reduction and internal fixation using an intramedullary compression screw and was allowed to return to competition by the end of the sixth week postsurgery.

CONCLUSIONS

Treatment of Jones fracture should be individualized, based on the athlete's needs, the history and clinical presentation, and the initial radiographic appearance of the injury. The literature indicates that a rapid return to activity can be realized using rigid internal fixation and may be the treatment of choice in athletes.

Older women's health: clinical care in the postmenopausal years. A roundtable discussion part 2

Prevention of late-life disability is an important goal in managing the health care of older women. Hormone replacement therapy and regular exercise can protect against osteoporosis and heart disease. Dietary measures can control weight and prevent diabetes. Adequate calcium and vitamin D intake help protect bones from fractures. Mammography and Pap smears are proven screens for early cancer detection. Depression is not unusual in older women, but it is often masked by physical symptoms. Physicians can help women at risk for caregiver burnout by providing referrals and information on community resources. Use of other health professionals, as well as patient education videos and printed materials, can help physicians provide comprehensive care within the time limits of office practice.

Older women's health: 'taking the pulse' reveals gender gap in medical care

In the United States, for every 100 men age 65 and older, there are 147 women, a ratio that has social and medical consequences. Five panelists "take the pulse" of older women's health in general and in the offices of primary care physicians in particular. They assess the status of medical education and the need to include older women in research and drug trials, issues of gender bias in health insurance and quality of treatment, ways to improve the use of preventive health services--such as mammography and Pap smears--by older women, and the role of office physicians in identifying and helping victims of domestic violence.

Corneal tissue levels of topically applied ciprofloxacin

The effectiveness of the fluoroquinolone ciprofloxacin is dependent on stromal drug concentrations which exceed the minimum inhibitory concentration90 (MIC90). The purpose of this study is to compare corneal tissue ciprofloxacin levels in patients exposed to three ciprofloxacin dosing regimens before undergoing penetrating keratoplasty. Thirty-one patients were assigned to one of three treatment groups. Group 1 followed a ciprofloxacin dosing regimen compatible with home use [two drops of 0.3% ciprofloxacin (Ciloxan; Alcon Laboratories, Fort Worth, TX, U.S.A.) every 4 h over a 24-h period]. Groups 2 and 3 followed a more tightly controlled dosing regimen designed for a health-care setting (two drops of Ciloxan applied by a trained professional every 15 min over a 4-h period). In groups 1 and 2, corneal epithelium was left intact, whereas in group 3 corneas were abraded. Corneal tissue samples were surgically obtained. Excised buttons were frozen and Ciloxan concentration determined by high-pressure liquid chromatography. Ciloxan corneal tissue concentrations (mean +/- SD) were 8.82 +/- 8.24 micrograms/g tissue in group 1, 166.20 +/- 336.94 micrograms/g tissue in group 2, and 938.30 +/- 1,081.51 micrograms/g tissue in group 3. Ciloxan penetration can be improved by administering the drug in a controlled setting at 15-min intervals over a 4-h period. Individual Ciloxan concentrations exceeded the MIC90 for most key ocular pathogens despite wide variability in all experimental groups.

Choice matters: enrollees' views of their health plans

Enrollees' views of their health plans and physicians are important measures of the performance of the health care system. The Commonwealth Fund's 1994 survey of 3,000 adults in fee-for-service and managed care organizations documents enrollees' experiences with choosing a plan and satisfaction with that plan. Fee-for-service enrollees were more satisfied with their plan's access to and quality of care; managed care enrollees were more satisfied with their plan's cost, paperwork, and coverage of preventive care. The survey also found a high rate of involuntary plan changing, limited choice of physicians, and low levels of satisfaction among low-income managed care enrollees.

Predictors of nursing home admission in a biracial population

Racial differences in predictors of institutionalization were studied in a biracial North Carolina cohort (n = 4074). During 3 years of follow-up, 8.5% of Whites and 6.4% of African Americans were admitted to nursing homes. African Americans were one half as likely as Whites to be institutionalized after adjustment for other risk factors. Among Whites, impaired activities of daily living and cognition were the strongest predictors; among African Americans, impaired instrumental activities of daily living and prior history of nursing home use were strongest. Racial differences in nursing home use were not explained by financial and social support or physical and cognitive impairment.

Five-year corneal graft survival. A large, single-center patient cohort

OBJECTIVE

To determine the survival rates and causes of secondary graft failure in a large, consecutive series of penetrating keratoplasties.

DESIGN

All eyes undergoing penetrating keratoplasty at a single center were evaluated for factors relating to penetrating keratoplasty preoperatively, surgically, and postoperatively at 1, 3, 6, 9, 12, 18, and 24 months and then at yearly intervals. Since 1986, data analysis has been prospective.

SETTING

A large, private practice, tertiary center for corneal disorders and surgery.

PATIENTS

A consecutive series of 1819 penetrating keratoplasties performed from August 1982 through August 1990; 13 eyes with primary graft failure were excluded.

MAIN OUTCOME MEASURE

Graft failure and causes of failure. Follow-up ranged from 1 to 96 months, with a mean of 26.6 months.

RESULTS

Pseudophakic bullous keratopathy was the most common diagnosis necessitating keratoplasty (38.6%). Secondary failures occurred 111 times (6.1%). The 2- and 5-year survival rates for all grafts in the study were 95% and 91%, respectively. While endothelial failure as a result of immunologic allograft reactions was the most common cause of graft failure (27%), problems with the external surface of the graft caused nearly as many failures (25%). The risk of failure from surface-related problems was highest at 3 months after surgery. There were significantly decreased survival rates for grafts in eyes with regrafts (P < .0001), in eyes left aphakic at keratoplasty (P < .0001), and in eyes with deep stromal vascularization (P < .0001).

CONCLUSION

Penetrating keratoplasty is a successful form of transplantation, and survival rates are gradually increasing. The risk of graft failure appears highest within the first year after transplantation.