Gout in Native Hawaiian Patients in Hawai'i: Clinical Characteristics and Disparities.

OBJECTIVE: The purpose of this study was to investigate differences in clinical characteristics and health care use of Native Hawaiian and White patients with gout. METHODS: We performed a retrospective chart review of Native Hawaiian and White patients with gout treated from 2011 to 2017 within a large health care system in Hawai'i. We compared demographic characteristics, clinical outcomes, and risk factors for gout. We used multivariable logistic regression to identify predictive factors of emergency department visits. RESULTS: We identified 270 Native Hawaiian patients with gout and 239 White patients with gout. The Native Hawaiian patients were younger on average (54.0 vs 64.0 years; P < 0.0001) and had an earlier onset of disease (50.0 vs 57.0 years; P < 0.0001). Native Hawaiian patients with gout had higher mean (7.58 vs 6.87 mg/dL; P < 0.0001) and maximum (10.30 vs 9.50 mg/dL; P < 0.0001) serum urate levels compared to White patients with gout. Native Hawaiian patients with gout also had a greater number of tophi (median 2.00 vs 1.00; P < 0.0001). Native Hawaiians patients with gout were 2.7 times more likely to have frequent (≥1) emergency department visits than White patients with gout. Native Hawaiian patients with gout were less likely to have a therapeutic serum urate ≤6.0 mg/dL and had lower rates of rheumatology specialty care. CONCLUSION: Native Hawaiian patients have a higher disease burden of gout, with earlier disease onset and more tophi. Native Hawaiian patients with gout are more likely to use emergency services for gout and have lower rates of rheumatology specialty care compared to White patients. Future studies are needed to promote culturally appropriate preventive care and management of gout in Native Hawaiians.

Limbic Encephalitis Associated with Human Herpesvirus-7 Infection in an Immunocompetent Adolescent.

Despite the ubiquitous nature of human herpesvirus-7 (HHV-7) infection, its clinical significance in the central nervous system (CNS) is poorly understood. However, the related human herpesvirus-6 (HHV-6), which has remarkable genomic similarity to HHV-7, is linked to encephalitis. We present the case of a 17-year-old immunocompetent male with remote history of seizure who arrived in status epilepticus. Upon resolution, he required hospitalization for worsening encephalopathy. Electroencephalogram (EEG) revealed bilateral temporal lobe dysfunction and magnetic resonance imaging (MRI) showed increased signaling in bilateral medial temporal lobes with hippocampal microhemorrhages. Empiric intravenous (IV) acyclovir was initiated despite initially negative cerebrospinal fluid (CSF) studies due to concern for herpes simplex virus (HSV) encephalitis. The patient improved and was discharged on hospital day 13 (HD13). After discharge, a human metagenomics CSF panel resulted positive only for HHV-7, making a case for possible etiology and empiric treatment of HHV-7 despite delayed CSF and serum studies.

The Suicide Prevention, Depression Awareness, and Clinical Engagement Program for Faculty and Residents at the University of California, Davis Health.

OBJECTIVE: The objective of the study is to present results of a depression and suicide screening and treatment referral program for physicians at an academic medical center. METHODS: An anonymous web-based screening questionnaire was sent to all physicians at a large academic center. Responses were classified as indicating either high, moderate, or low risk for depression and suicide. Physicians at high and moderate risk were contacted by a counselor through a messaging system. The counselor's message contained information on risk level and an invitation to meet in person. High-risk respondents who did not reply to the message or declined to meet received mental health resources. Respondents who met with the counselor were offered individualized treatment referrals and to participate in a 1-year follow-up of self-reports every 3 months. RESULTS: The questionnaire was sent to approximately 1800 residents, fellows, and faculty from February 2013 through March 2019. A total of 639 questionnaires were received, 100 were excluded for various reasons, and 539 were used to conduct analyses (14.4% response rate). The majority of respondents were classified at moderate (333 [62%]) or high (193 [36%]) risk for depression or suicide. Eighty-three respondents were referred for mental health care, and 14 provided data for the follow-up study. CONCLUSIONS: Results of screening physicians for depression and suicide at one academic medical center highlight the challenges of engaging most of them in this activity and the satisfaction of the minority who successfully engaged in a treatment referral program.

Radiographic and neurobehavioral profile of sports-related concussion associated with scholastic wrestling: a case report.

Sports-related concussions (SRCs) are typically characterized by transient neurologic deficits due to physiologic and metabolic brain injury. However, following an SRC, subsequent insults may lead to severe and permanent injury in the affected brain cells. We present the case of a 15-year-old female scholastic wrestler who developed acute encephalopathy, macroscopic white matter injury on imaging, and chronic behavioral changes from inadequate neuro-recovery after a documented SRC. We also compare her case with established SRC data, demonstrating that wrestling-related concussions and repetitive head impacts can produce similar degrees of diffuse neuroinflammation, myelinated axonopathy, blood-brain barrier disruption, and post-concussive symptoms.

Appointment completion in pediatric neurology telemedicine clinics serving underserved patients.

BACKGROUND: To determine whether telemedicine improves access to outpatient neurology care for underserved patients, we compared appointment completion between urban, in-person clinics and telemedicine clinics held in rural and underserved communities where neurology consultations are provided remotely. METHODS: In this retrospective study, we identified patients scheduled for outpatient care from UCDH pediatric neurologists between January 1, 2009, and July 31, 2017, in person and by telemedicine. Demographic and clinical variables were abstracted from electronic medical records. We evaluated the association between consultation modality and visit completion in overall and matched samples using hierarchical multivariable logistic regression. RESULTS: We analyzed 13,311 in-person appointments by 3,831 patients and 1,158 telemedicine appointments by 381 patients. The average travel time to the site of care was 45.8 ± 52.1 minutes for the in-person cohort and 22.3 ± 22.7 minutes for the telemedicine cohort. Telemedicine sites were located at an average travel time of 217.1 ± 114.8 minutes from UCDH. Telemedicine patients were more likely to have nonprivate insurance, lower education, and lower household income. They had different diagnoses and fewer complex chronic conditions. Telemedicine visits were more likely to be completed than either "cancelled" or missed ("no show") compared with in-person visits (OR 1.57, 95% CI: 1.34-1.83; OR 1.66, 95% CI: 1.31-2.10 matched on travel time to the site of care; OR 2.22, 95% CI: 1.66-2.98 matched on travel time to UCDH). CONCLUSIONS: The use of telemedicine for outpatient pediatric neurology visits has high odds of completion and can serve as an equal adjunct to in-person clinic visits.

Hospital Utilization Among Rural Children Served by Pediatric Neurology Telemedicine Clinics.

Importance: Telemedicine is increasingly used to provide outpatient pediatric neurology consultations in underserved communities. Although telemedicine clinics have been shown to improve access, little is known about how they alter patients' utilization of hospital services. Objective: To evaluate the association between access to telemedicine clinics and hospital utilization among underserved children with neurologic conditions. Design, Setting, and Participants: This retrospective cross-sectional study included 4169 patients who received outpatient care from pediatric neurologists affiliated with an academic children's hospital in California between January 1, 2009, and July 31, 2017, either in person or using telemedicine. Exposures: Consultation modality (telemedicine or in person) in the outpatient neurology clinics. Main Outcomes and Measures: Demographic and clinical variables were abstracted from the hospital's electronic medical records. The association between the modality of outpatient neurology care and patients' utilization of the emergency department and hospitalizations was evaluated. Both all-cause and neurologic condition-related hospital utilization were analyzed using multivariable negative binomial regression in overall and matched samples. Results: The telemedicine cohort comprised 378 patients (211 [55.8%] male), and the in-person cohort comprised 3791 patients (2090 [55.1%] male). The mean (SD) age at the first encounter was 7.4 (5.4) years for the telemedicine cohort and 7.8 (5.1) years for the in-person cohort. The telemedicine cohort was more likely than the in-person cohort to have nonprivate insurance (public insurance, self-pay, or uninsured), lower education, and lower household income. The rates of all-cause and neurologic hospital encounters were lower among children who received pediatric neurology consultations over telemedicine compared with children who received care in the in-person clinics (5.7 [95% CI, 3.5-8.0] vs 20.1 [95% CI, 18.1-22.1] per 100 patient-years and 3.7 [95% CI, 2.0-5.3] vs 8.9 [95% CI, 7.8-10.0] per 100 patient-years, respectively; P < .001). Even after adjusting for demographic and clinical factors, the telemedicine cohort had a lower risk of hospital encounters (emergency department visits and admissions) with an adjusted incidence rate ratio of 0.57 (95% CI, 0.38-0.88) for all-cause encounters and an adjusted incidence rate ratio of 0.60 (95% CI, 0.36-0.99) for neurologic encounters. After matching on travel time to the neurology clinic, the adjusted incidence rate ratio was 0.19 (95% CI, 0.04-0.83) for all-cause admissions and 0.14 (95% CI, 0.02-0.82) for neurologic admissions. Conclusions and Relevance: Pediatric neurology care through real-time, audiovisual telemedicine consultations was associated with lower hospital utilization compared with in-person consultations, suggesting that high-cost hospital encounters can be prevented by improving subspecialty access.

A Gene Expression Classifier from Whole Blood Distinguishes Benign from Malignant Lung Nodules Detected by Low-Dose CT.

Low-dose CT (LDCT) is widely accepted as the preferred method for detecting pulmonary nodules. However, the determination of whether a nodule is benign or malignant involves either repeated scans or invasive procedures that sample the lung tissue. Noninvasive methods to assess these nodules are needed to reduce unnecessary invasive tests. In this study, we have developed a pulmonary nodule classifier (PNC) using RNA from whole blood collected in RNA-stabilizing PAXgene tubes that addresses this need. Samples were prospectively collected from high-risk and incidental subjects with a positive lung CT scan. A total of 821 samples from 5 clinical sites were analyzed. Malignant samples were predominantly stage 1 by pathologic diagnosis and 97% of the benign samples were confirmed by 4 years of follow-up. A panel of diagnostic biomarkers was selected from a subset of the samples assayed on Illumina microarrays that achieved a ROC-AUC of 0.847 on independent validation. The microarray data were then used to design a biomarker panel of 559 gene probes to be validated on the clinically tested NanoString nCounter platform. RNA from 583 patients was used to assess and refine the NanoString PNC (nPNC), which was then validated on 158 independent samples (ROC-AUC = 0.825). The nPNC outperformed three clinical algorithms in discriminating malignant from benign pulmonary nodules ranging from 6-20 mm using just 41 diagnostic biomarkers. Overall, this platform provides an accurate, noninvasive method for the diagnosis of pulmonary nodules in patients with non-small cell lung cancer. SIGNIFICANCE: These findings describe a minimally invasive and clinically practical pulmonary nodule classifier that has good diagnostic ability at distinguishing benign from malignant pulmonary nodules.

The Suicide Prevention, Depression Awareness, and Clinical Engagement Program for Faculty and Residents at the University of California, Davis Health System.

OBJECTIVE: The authors replicated a program developed by UC San Diego, identified medical staff at risk for depression and suicide using a confidential online survey, and studied aspects of that program for 1 year. METHODS: The authors used a 35-item, online assessment of stress and depression depression developed and licensed by the American Foundation for Suicide Prevention that aims to identify and suicide risk and facilitate access to mental health services. RESULTS: During 2013/2014, all 1864 UC Davis residents/fellows and faculty physicians received an invitation to take the survey and 158 responded (8% response rate). Most respondents were classified at either moderate (86 [59%]) or high risk for depression or suicide (54 [37%]). Seventeen individuals (11%) were referred for further evaluation or mental health treatment. Ten respondents consented to participate in the follow-up portion of the program. Five of the six who completed follow-up surveys reported symptom improvement and indicated the program should continue. CONCLUSIONS: This program has led to continued funding and a plan to repeat the Wellness Survey annually. Medical staff will be regularly reminded of its existence through educational interventions, as the institutional and professional culture gradually changes to promptly recognize and seek help for physicians' psychological distress.

Choline Acetyltransferase Mutations Causing Congenital Myasthenic Syndrome: Molecular Findings and Genotype-Phenotype Correlations.

Choline acetyltransferase catalyzes the synthesis of acetylcholine at cholinergic nerves. Mutations in human CHAT cause a congenital myasthenic syndrome due to impaired synthesis of ACh; this severe variant of the disease is frequently associated with unexpected episodes of potentially fatal apnea. The severity of this condition varies remarkably, and the molecular factors determining this variability are poorly understood. Furthermore, genotype-phenotype correlations have been difficult to establish in patients with biallelic mutations. We analyzed the protein expression of phosphorylated ChAT of seven CHAT mutations, p.Val136Met, p.Arg207His, p.Arg186Trp, p.Val194Leu, p.Pro211Ala, p.Arg566Cys, and p.Ser694Cys, in HEK-293 cells to phosphorylated ChAT, determined their enzyme kinetics and thermal stability, and examined their structural changes. Three mutations, p.Arg207His, p.Arg186Trp, and p.Arg566Cys, are novel, and p.Val136Met and p.Arg207His are homozygous in three families and associated with severe disease. The characterization of mutants showed a decrease in the overall catalytic efficiency of ChAT; in particular, those located near the active-site tunnel produced the most seriously disruptive phenotypic effects. On the other hand, p.Val136Met, which is located far from both active and substrate-binding sites, produced the most drastic reduction of ChAT expression. Overall, CHAT mutations producing low enzyme expression and severe kinetic effects are associated with the most severe phenotypes.

Pediatric super-refractory status epilepticus treated with allopregnanolone.

Super-refractory status epilepticus is a life-threatening condition. Resistance to benzodiazepine and barbiturate treatment for this disorder is thought to be due to internalization of synaptic γ-aminobutyric acid (GABA)A receptors, and withdrawal of benzodiazepines and barbiturates during treatment often triggers seizure recurrence. The neurosteroid allopregnanolone acts as a positive allosteric modulator of synaptic and extrasynaptic GABAA receptors. Here we describe the use of allopregnanolone in 2 pediatric patients with super-refractory status epilepticus. This treatment allowed the general anesthetic infusions to be weaned with resolution of status epilepticus. This is the first report of allopregnanolone use to treat status epilepticus in children.

Comparative functional genomics of adaptation to muscular disuse in hibernating mammals.

Hibernation is an energy-saving adaptation that involves a profound suppression of physical activity that can continue for 6-8 months in highly seasonal environments. While immobility and disuse generate muscle loss in most mammalian species, in contrast, hibernating bears and ground squirrels demonstrate limited muscle atrophy over the prolonged periods of physical inactivity during winter, suggesting that hibernating mammals have adaptive mechanisms to prevent disuse muscle atrophy. To identify common transcriptional programmes that underlie molecular mechanisms preventing muscle loss, we conducted a large-scale gene expression screen in hind limb muscles comparing hibernating and summer-active black bears and arctic ground squirrels using custom 9600 probe cDNA microarrays. A molecular pathway analysis showed an elevated proportion of overexpressed genes involved in all stages of protein biosynthesis and ribosome biogenesis in muscle of both species during torpor of hibernation that suggests induction of translation at different hibernation states. The induction of protein biosynthesis probably contributes to attenuation of disuse muscle atrophy through the prolonged periods of immobility of hibernation. The lack of directional changes in genes of protein catabolic pathways does not support the importance of metabolic suppression for preserving muscle mass during winter. Coordinated reduction in multiple genes involved in oxidation-reduction and glucose metabolism detected in both species is consistent with metabolic suppression and lower energy demand in skeletal muscle during inactivity of hibernation.

Inflammation and Its Correlates in Regenerative Wound Healing: An Alternate Perspective.

Objective: The wound healing response may be viewed as partially overlapping sets of two physiological processes, regeneration and wound repair with the former overrepresented in some lower species such as newts and the latter more typical of mammals. A robust and quantitative model of regenerative healing has been described in Murphy Roths Large (MRL) mice in which through-and-through ear hole wounds in the ear pinna leads to scarless healing and replacement of all tissue through blastema formation and including cartilage. Since these mice are naturally autoimmune and display many aspects of an enhanced inflammatory response, we chose to examine the inflammatory status during regenerative ear hole closure and observed that inflammation has a clear positive effect on regenerative healing. Approach: The inflammatory gene expression patterns (Illumina microarrays) of early healing ear tissue from regenerative MRL and nonregenerative C57BL/6 (B6) strains are presented along with a survey of innate inflammatory cells found in this tissue type pre and postinjury. The role of inflammation on healing is tested using a COX-2 inhibitor. Innovation and Conclusion: We conclude that (1) enhanced inflammation is consistent with, and probably necessary, for a full regenerative response and (2) the inflammatory gene expression and cell distribution patterns suggest a novel mast cell population with markers found in both immature and mature mast cells that may be a key component of regeneration.

Identification of a 251 gene expression signature that can accurately detect M. tuberculosis in patients with and without HIV co-infection.

BACKGROUND: Co-infection with tuberculosis (TB) is the leading cause of death in HIV-infected individuals. However, diagnosis of TB, especially in the presence of an HIV co-infection, can be limiting due to the high inaccuracy associated with the use of conventional diagnostic methods. Here we report a gene signature that can identify a tuberculosis infection in patients co-infected with HIV as well as in the absence of HIV. METHODS: We analyzed global gene expression data from peripheral blood mononuclear cell (PBMC) samples of patients that were either mono-infected with HIV or co-infected with HIV/TB and used support vector machines to identify a gene signature that can distinguish between the two classes. We then validated our results using publically available gene expression data from patients mono-infected with TB. RESULTS: Our analysis successfully identified a 251-gene signature that accurately distinguishes patients co-infected with HIV/TB from those infected with HIV only, with an overall accuracy of 81.4% (sensitivity = 76.2%, specificity = 86.4%). Furthermore, we show that our 251-gene signature can also accurately distinguish patients with active TB in the absence of an HIV infection from both patients with a latent TB infection and healthy controls (88.9-94.7% accuracy; 69.2-90% sensitivity and 90.3-100% specificity). We also demonstrate that the expression levels of the 251-gene signature diminish as a correlate of the length of TB treatment. CONCLUSIONS: A 251-gene signature is described to (a) detect TB in the presence or absence of an HIV co-infection, and (b) assess response to treatment following anti-TB therapy.

Delta-aminolevulinate-induced host-parasite porphyric disparity for selective photolysis of transgenic Leishmania in the phagolysosomes of mononuclear phagocytes: a potential novel platform for vaccine delivery.

Leishmania double transfectants (DTs) expressing the 2nd and 3rd enzymes in the heme biosynthetic pathway were previously reported to show neogenesis of uroporphyrin I (URO) when induced with delta-aminolevulinate (ALA), the product of the 1st enzyme in the pathway. The ensuing accumulation of URO in DT promastigotes rendered them light excitable to produce reactive oxygen species (ROS), resulting in their cytolysis. Evidence is presented showing that the DTs retained wild-type infectivity to their host cells and that the intraphagolysosomal/parasitophorous vacuolar (PV) DTs remained ALA inducible for uroporphyrinogenesis/photolysis. Exposure of DT-infected cells to ALA was noted by fluorescence microscopy to result in host-parasite differential porphyrinogenesis: porphyrin fluorescence emerged first in the host cells and then in the intra-PV amastigotes. DT-infected and control cells differed qualitatively and quantitatively in their porphyrin species, consistent with the expected multi- and monoporphyrinogenic specificities of the host cells and the DTs, respectively. After ALA removal, the neogenic porphyrins were rapidly lost from the host cells but persisted as URO in the intra-PV DTs. These DTs were thus extremely light sensitive and were lysed selectively by illumination under nonstringent conditions in the relatively ROS-resistant phagolysosomes. Photolysis of the intra-PV DTs returned the distribution of major histocompatibility complex (MHC) class II molecules and the global gene expression profiles of host cells to their preinfection patterns and, when transfected with ovalbumin, released this antigen for copresentation with MHC class I molecules. These Leishmania mutants thus have considerable potential as a novel model of a universal vaccine carrier for photodynamic immunotherapy/immunoprophylaxis.

Preservation of bone mass and structure in hibernating black bears (Ursus americanus) through elevated expression of anabolic genes.

Physical inactivity reduces mechanical load on the skeleton, which leads to losses of bone mass and strength in non-hibernating mammalian species. Although bears are largely inactive during hibernation, they show no loss in bone mass and strength. To obtain insight into molecular mechanisms preventing disuse bone loss, we conducted a large-scale screen of transcriptional changes in trabecular bone comparing winter hibernating and summer non-hibernating black bears using a custom 12,800 probe cDNA microarray. A total of 241 genes were differentially expressed (P < 0.01 and fold change >1.4) in the ilium bone of bears between winter and summer. The Gene Ontology and Gene Set Enrichment Analysis showed an elevated proportion in hibernating bears of overexpressed genes in six functional sets of genes involved in anabolic processes of tissue morphogenesis and development including skeletal development, cartilage development, and bone biosynthesis. Apoptosis genes demonstrated a tendency for downregulation during hibernation. No coordinated directional changes were detected for genes involved in bone resorption, although some genes responsible for osteoclast formation and differentiation (Ostf1, Rab9a, and c-Fos) were significantly underexpressed in bone of hibernating bears. Elevated expression of multiple anabolic genes without induction of bone resorption genes, and the down regulation of apoptosis-related genes, likely contribute to the adaptive mechanism that preserves bone mass and structure through prolonged periods of immobility during hibernation.

Resection of non-small cell lung cancers reverses tumor-induced gene expression changes in the peripheral immune system.

PURPOSE: To characterize the interactions of non-small cell lung cancer (NSCLC) tumors with the immune system at the level of mRNA and microRNA (miRNA) expression and to define expression signatures that characterize the presence of a malignant tumor versus a nonmalignant nodule. EXPERIMENTAL DESIGN: We have examined the changes of both mRNA and miRNA expression levels in peripheral blood mononuclear cells (PBMC) between paired samples collected from NSCLC patients before and after tumor removal using Illumina gene expression arrays. RESULTS: We found that malignant tumor removal significantly changes expression of more than 3,000 protein-coding genes, especially genes in pathways associated with suppression of the innate immune response, including natural killer cell signaling and apoptosis-associated ceramide signaling. Binding sites for the ETS domain transcription factors ELK1, ELK4, and SPI1 were enriched in promoter regions of genes upregulated in the presence of a tumor. Additional important regulators included five miRNAs expressed at significantly higher levels before tumor removal. Repressed protein-coding targets of those miRNAs included many transcription factors, several involved in immunologically important pathways. Although there was a significant overlap in the effects of malignant tumors and benign lung nodules on PBMC gene expression, we identified one gene panel which indicates a tumor or nodule presence and a second panel that can distinguish malignant from nonmalignant nodules. CONCLUSIONS: A tumor presence in the lung influences mRNA and miRNA expression in PBMC and this influence is reversed by tumor removal. These results suggest that PBMC gene expression signatures could be used for lung cancer diagnosis.

Modulation of gene expression in heart and liver of hibernating black bears (Ursus americanus).

BACKGROUND: Hibernation is an adaptive strategy to survive in highly seasonal or unpredictable environments. The molecular and genetic basis of hibernation physiology in mammals has only recently been studied using large scale genomic approaches. We analyzed gene expression in the American black bear, Ursus americanus, using a custom 12,800 cDNA probe microarray to detect differences in expression that occur in heart and liver during winter hibernation in comparison to summer active animals. RESULTS: We identified 245 genes in heart and 319 genes in liver that were differentially expressed between winter and summer. The expression of 24 genes was significantly elevated during hibernation in both heart and liver. These genes are mostly involved in lipid catabolism and protein biosynthesis and include RNA binding protein motif 3 (Rbm3), which enhances protein synthesis at mildly hypothermic temperatures. Elevated expression of protein biosynthesis genes suggests induction of translation that may be related to adaptive mechanisms reducing cardiac and muscle atrophies over extended periods of low metabolism and immobility during hibernation in bears. Coordinated reduction of transcription of genes involved in amino acid catabolism suggests redirection of amino acids from catabolic pathways to protein biosynthesis. We identify common for black bears and small mammalian hibernators transcriptional changes in the liver that include induction of genes responsible for fatty acid ß oxidation and carbohydrate synthesis and depression of genes involved in lipid biosynthesis, carbohydrate catabolism, cellular respiration and detoxification pathways. CONCLUSIONS: Our findings show that modulation of gene expression during winter hibernation represents molecular mechanism of adaptation to extreme environments.

Genome-wide DNA methylation analysis in cohesin mutant human cell lines.

The cohesin complex has recently been shown to be a key regulator of eukaryotic gene expression, although the mechanisms by which it exerts its effects are poorly understood. We have undertaken a genome-wide analysis of DNA methylation in cohesin-deficient cell lines from probands with Cornelia de Lange syndrome (CdLS). Heterozygous mutations in NIPBL, SMC1A and SMC3 genes account for ∼65% of individuals with CdLS. SMC1A and SMC3 are subunits of the cohesin complex that controls sister chromatid cohesion, whereas NIPBL facilitates cohesin loading and unloading. We have examined the methylation status of 27 578 CpG dinucleotides in 72 CdLS and control samples. We have documented the DNA methylation pattern in human lymphoblastoid cell lines (LCLs) as well as identified specific differential DNA methylation in CdLS. Subgroups of CdLS probands and controls can be classified using selected CpG loci. The X chromosome was also found to have a unique DNA methylation pattern in CdLS. Cohesin preferentially binds to hypo-methylated DNA in control LCLs, whereas the differential DNA methylation alters cohesin binding in CdLS. Our results suggest that in addition to DNA methylation multiple mechanisms may be involved in transcriptional regulation in human cells and in the resultant gene misexpression in CdLS.

Protogenin defines a transition stage during embryonic neurogenesis and prevents precocious neuronal differentiation.

Many Ig superfamily members are expressed in the developing nervous system, but the functions of these molecules during neurogenesis are not all clear. Here, we explore the expression and function of one of members of this superfamily, protogenin (PRTG), in the developing nervous system. Expression of PRTG protein is strong in the neural tube of mouse embryos between embryonic days 7.75 and 9.5 but disappears after embryonic day 10.5 when the neural progenitor marker nestin expresses prominently. Perturbation of PRTG activity in P19 embryonal carcinoma cells and in chick embryos, by either RNA interference or a dominant-negative PRTG mutant, increases neuronal differentiation. Using yeast two-hybrid screening and an in situ binding assay, we were able to identify ERdj3 (a stress-inducible endoplasmic reticulum DnaJ homolog) as a putative PRTG ligand. Addition of purified ERdj3 protein into the P19 differentiation assay reduced neurogenesis. This effect was blocked by addition of either a neutralizing antibody against PRTG or purified PRTG ectodomain protein, indicating that the effect of ERdj3 on neurogenesis is mediated through PRTG. Forced expression of ERdj3 in the chick neural tube also impairs neuronal differentiation. Together, these results suggest that expression of PRTG defines a stage between pluripotent epiblasts and committed neural progenitors, and its signaling plays a critical role in suppressing premature neuronal differentiation during early neural development.

Gene expression profiles in peripheral blood mononuclear cells can distinguish patients with non-small cell lung cancer from patients with nonmalignant lung disease.

Early diagnosis of lung cancer followed by surgery presently is the most effective treatment for non-small cell lung cancer (NSCLC). An accurate, minimally invasive test that could detect early disease would permit timely intervention and potentially reduce mortality. Recent studies have shown that the peripheral blood can carry information related to the presence of disease, including prognostic information and information on therapeutic response. We have analyzed gene expression in peripheral blood mononuclear cell samples including 137 patients with NSCLC tumors and 91 patient controls with nonmalignant lung conditions, including histologically diagnosed benign nodules. Subjects were primarily smokers and former smokers. We have identified a 29-gene signature that separates these two patient classes with 86% accuracy (91% sensitivity, 80% specificity). Accuracy in an independent validation set, including samples from a new location, was 78% (sensitivity of 76% and specificity of 82%). An analysis of this NSCLC gene signature in 18 NSCLCs taken presurgery, with matched samples from 2 to 5 months postsurgery, showed that in 78% of cases, the signature was reduced postsurgery and disappeared entirely in 33%. Our results show the feasibility of using peripheral blood gene expression signatures to identify early-stage NSCLC in at-risk populations.