Ebf1 is a mouse deafness gene and deletion causes a dramatic increase in hair cells and support cells of the organ of Corti.

Following up on our previous observation that early B cell factor (EBF) sites are enriched in open chromatin of the developing sensory epithelium of the mouse cochlea, we investigated the effect of deletion of Ebf1 on inner ear development. We used a Cre driver to delete Ebf1 at the otocyst stage prior to development of the cochlea. We examined the cochlea at postnatal day (P) 1 and found that the sensory epithelium had doubled in size but the length of the cochlear duct was unaffected. We also found that deletion of Ebf1 led to ectopic sensory patches in the Kölliker's organ. Innervation of the developing organ of Corti was disrupted with no obvious spiral bundles. The ectopic patches were also innervated. All the extra hair cells (HCs) within the sensory epithelium and Kölliker's organ contained mechanoelectrical transduction channels as indicated by rapid uptake of FM1-43. The excessive numbers of HCs were still present in the adult Ebf1 conditional knockout (cKO) animal. The animals had no detectable auditory brainstem response (ABR) suggesting that this gene is essential for hearing development.

Endolymphatic sac decompression effect on secondary symptoms of Meniere's disease.

OBJECTIVE: To evaluate if endolymphatic sac decompression (ESD) significantly improves secondary symptoms of Meniere's disease including tinnitus and aural fullness. STUDY DESIGN: Survey study with retrospective chart review. SETTING: Tertiary care center. METHODS: Survey of adult patients with Meniere's disease that underwent primary ESD surgery from 2015 to 2020. Subjective reporting of pre- and postoperative aural fullness and tinnitus based on postoperative survey. Survey results and audiologic data of the patients that reported were compared pre- and postoperatively. RESULTS: Statistical analysis was performed using weighted kappa statistics to examine the level of agreement. There was a value of 0.12 for pre- and postoperative aural fullness, indicating a difference in the two groups with 77 % having improvement and only 4 % having worsening. There was a value of 0.21 for pre- and postoperative tinnitus, demonstrating a lack of agreement with 58 % having improvement and 4 % having worsening. Overall, there was significant improvement in both tinnitus and aural fullness postoperatively. There was no significant difference in word recognition score, speech reception threshold, or pure tone average between the pre- and postoperative group based on paired t-test. CONCLUSIONS: There is a significant improvement in both aural fullness and tinnitus for patients undergoing ESD with no negative effect on audiologic status. ESD is a viable option for treatment of Meniere's disease with vertigo, aural fullness, and tinnitus relief. Future prospective studies are needed to further improve the evidence of ESD's effect on secondary symptoms of Meniere's disease.

Novel cell types and developmental lineages revealed by single-cell RNA-seq analysis of the mouse crista ampullaris.

This study provides transcriptomic characterization of the cells of the crista ampullaris, sensory structures at the base of the semicircular canals that are critical for vestibular function. We performed single-cell RNA-seq on ampullae microdissected from E16, E18, P3, and P7 mice. Cluster analysis identified the hair cells, support cells and glia of the crista as well as dark cells and other nonsensory epithelial cells of the ampulla, mesenchymal cells, vascular cells, macrophages, and melanocytes. Cluster-specific expression of genes predicted their spatially restricted domains of gene expression in the crista and ampulla. Analysis of cellular proportions across developmental time showed dynamics in cellular composition. The new cell types revealed by single-cell RNA-seq could be important for understanding crista function and the markers identified in this study will enable the examination of their dynamics during development and disease.

Utility and value of pre-operative CT and MRI for cochlear implantation in the elderly.

PURPOSE: To determine the utility and value of pre-operative imaging among the elderly population ≥70 y.o. with bilateral progressive sensorineural hearing loss undergoing cochlear implantation. MATERIALS AND METHODS: A retrospective, cross-sectional review was performed at a tertiary referral center between 2010 and 2018 including patients ≥70 y.o. with bilateral presbycusis who underwent preoperative imaging and cochlear implantation. Primary outcome was whether pre-operative imaging changed the surgeon's surgical plan such as side of implant or abort procedure entirely. Patient characteristics including age, sex, side of implant, imaging modality, whether imaging changed surgical plan, and surgical complications were reviewed. One-way analysis of variance with post-hoc tests using the Bonferroni and Fisher's exact test were used to examine differences between groups. Secondary outcome was cost of preoperative imaging. RESULTS: One hundred thirty-three patients (mean age 79.38 [5.51 SD]) who underwent a total of 142 surgical cases and 147 total scans. There were 92, 27, and 14 patients who underwent CT, MRI, or both, respectfully (n=133). Of the 142 implants that were placed, preoperative imaging did not reveal a contraindication to placing implant on one side over another. Total cost of imaging was $29,694. Estimated cost if 20% of cochlear implant eligible patients ≥70 y.o. underwent imaging is $7,763,490. CONCLUSION: Decreasing unnecessary preoperative imaging can potentially decrease cost in cochlear implantation. In this sample, preoperative imaging did not affect the surgeon's choice of which side to operate on. However, imaging may provide an anatomic roadmap and contribute to either surgical confidence or caution. With the increasing amount of cochlear implant eligible elderly adults, preoperative imaging needs to be more clearly defined in this unique population.

STAT Signaling Modifies Ascl1 Chromatin Binding and Limits Neural Regeneration from Muller Glia in Adult Mouse Retina.

Müller glia (MG) serve as sources for retinal regeneration in non-mammalian vertebrates. We find that this process can be induced in mouse MG, after injury, by transgenic expression of the proneural transcription factor Ascl1 and the HDAC inhibitor TSA. However, new neurons are generated only from a subset of MG. Identifying factors that limit Ascl1-mediated MG reprogramming could make this process more efficient. In this study, we test whether injury-induced STAT activation hampers the ability of Ascl1 to reprogram MG into retinal neurons. Single-cell RNA-seq shows that progenitor-like cells derived from Ascl1-expressing MG have a higher level of STAT signaling than do those cells that become neurons. Ascl1-ChIPseq and ATAC-seq show that STAT potentially directs Ascl1 to developmentally inappropriate targets. Using a STAT inhibitor, in combination with our previously described reprogramming paradigm, we found a large increase in the ability of MG to generate neurons.

Validating the Utility of High Frequency Ocular Vestibular Evoked Myogenic Potential Testing in the Diagnosis of Superior Semicircular Canal Dehiscence.

INTRODUCTION: Ocular vestibular evoked myogenic potential (oVEMP) is a diagnostic test employed in the evaluation of superior semicircular canal dehiscence (SSCD) syndrome. Previous work showed that the presence of the n10 component of oVEMP at 4000 Hz was diagnostic of SSCD with perfect sensitivity and specificity of 1.0 in a series of 22 patients. This study sought to validate the diagnostic accuracy of high-frequency oVEMP with comparison to 500 Hz oVEMP and cervical vestibular evoked myogenic potential (cVEMP) in a larger series of patients. METHODS: Retrospective chart review of 171 patients with clinical symptoms consistent with SSCD who underwent oVEMP and cVEMP testing. Dehiscence of the superior semicircular canal (SCC) on high-resolution computed tomography (CT) imaging of the temporal bone was used to identify cases of likely SSCD. The presence or absence of 4000 Hz oVEMP n10 responses, increased amplitude of 500 Hz oVEMP responses, and reduced threshold of 500 Hz cVEMP responses were identified for each patient. RESULTS: SCC dehiscence was identified by CT imaging in 48 of 171 patients with symptoms consistent with SSCD. High-frequency oVEMP testing at 4000 Hz elicited a n10 response in 40 of 48 (83.3%) of patients and was present in 48 of 171 (28.1%) patients overall. The corresponding sensitivity was 0.83, specificity was 0.93, positive predictive value was 0.83, and negative predictive value was 0.93. oVEMP and cVEMP testing at 500 Hz was less accurate with sensitivity of 0.62 and 0.64, respectively, and specificity of 0.73 and 0.73, respectively. CONCLUSION: The presence of a 4000 Hz oVEMP n10 response was predictive of SSC dehiscence on CT imaging among patients with symptoms consistent with SSCD with sensitivity of 0.83, specificity of 0.93, positive predictive value of 0.83, and negative predictive value of 0.93. A negative finding strongly rules out SSCD. High-frequency oVEMP was more accurate than 500 Hz oVEMP or cVEMP.

The use of cochlear implantation in the elderly.

PURPOSE OF REVIEW: To evaluate the impact of cochlear implantation on hearing outcomes, quality of life, complications, and cognitive function in elderly patients. RECENT FINDINGS: Nine articles published between 2014 and 2019 pertain to cochlear implantation in the elderly population. The findings conclude that cochlear implantation improves autonomy and overall quality of life in the elderly. SUMMARY: Design: a pubmed search was employed with title search terms 'cochlear implant,' AND 'elderly' or 'aged.' Twenty-one articles were generated. Of the 21, articles without evidence-based findings were excluded and those published more than 5 years ago were excluded, yielding a final number of nine articles for review. RESULTS: nine articles published on the use of cochlear implantation in the elderly were identified through the literature search between the years 2014-2019. Outcomes included quality of life, speech recognition improvement, improvement in cognitive function as defined by geriatric validated scales, outcomes of hearing rehabilitation, improvement in verbal comprehension, surgical complications, and the ability to manage the external components of the device. CONCLUSION: cochlear implantation improves autonomy and the quality of life in the elderly. Age should not be a factor limiting surgical decision-making, and cochlear implantation can be utilized as a well tolerated, efficient treatment option for severe-to-profound hearing loss in the elderly population.

Open chromatin dynamics in prosensory cells of the embryonic mouse cochlea.

Hearing loss is often due to the absence or the degeneration of hair cells in the cochlea. Understanding the mechanisms regulating the generation of hair cells may therefore lead to better treatments for hearing disorders. To elucidate the transcriptional control mechanisms specifying the progenitor cells (i.e. prosensory cells) that generate the hair cells and support cells critical for hearing function, we compared chromatin accessibility using ATAC-seq in sorted prosensory cells (Sox2-EGFP+) and surrounding cells (Sox2-EGFP-) from E12, E14.5 and E16 cochlear ducts. In Sox2-EGFP+, we find greater accessibility in and near genes restricted in expression to the prosensory region of the cochlear duct including Sox2, Isl1, Eya1 and Pou4f3. Furthermore, we find significant enrichment for the consensus binding sites of Sox2, Six1 and Gata3-transcription factors required for prosensory development-in the open chromatin regions. Over 2,200 regions displayed differential accessibility with developmental time in Sox2-EGFP+ cells, with most changes in the E12-14.5 window. Open chromatin regions detected in Sox2-EGFP+ cells map to over 48,000 orthologous regions in the human genome that include regions in genes linked to deafness. Our results reveal a dynamic landscape of open chromatin in prosensory cells with potential implications for cochlear development and disease.

Accuracy and precision of age determination using growth layer groups for California sea lions (Zalophus californianus) with known ages.

Age determination from counts of growth layer groups (GLGs) in tooth dentine is a common method for aging marine mammals. Using known-aged animals, we validated this method for acid etched teeth of California sea lions (CSLs), Zalophus californianus. Between 1991 and 2013, the upper left canine (n = 33) was collected opportunistically during necropsy from animals tagged or branded as pups that later died. Overall, 55%-61% of age estimates by GLG counting were within 1 yr of the known-age in the sample of 1-30-yr-old CSLs. Accuracy of age estimates was found to be dependent on age of the CSLs, however. 71%-79% of age estimates were within 1 yr of the known-age in CSLs <10 yr old. These findings support the validity of counting GLGs to estimate age for CSLs <10 yr old to within 1 yr of accuracy.

Effects of 3,3'-Iminodipropionitrile on Hair Cell Numbers in Cristae of CBA/CaJ and C57BL/6J Mice.

This study examines absolute hair cell numbers in the cristae of C57BL/6J mice and CBA/CaJ mice from weaning to adulthood as well as the dose required for 3,3'-iminodiproprionitrile (IDPN)-injury of the cristae in C57BL/6J mice and CBA/CaJ mice, the two mouse strains most commonly used by inner ear researchers. In cristae of CBA/CaJ and C57BL/6J mice, no loss of hair cells was observed up to 24 weeks. In both strains, dose-dependent loss of hair cells was observed 7 days after IDPN treatment of 2-month-old mice (IC50 = 16.1 mmol/kg in C57BL/6J mice vs. 25.21 mmol/kg in CBA/CaJ mice). Four-month-old C57BL/6J mice exposed to IDPN developed dose-dependent vestibular dysfunction as indicated by increased activity and circling behavior in open field tests and by failure to swim 7 days after treatment. IDPN-hair cell injury in C57BL/6J mice and CBA/CaJ mice represents a fast and predictable experimental model for the study of vestibular degeneration and a platform for the testing of vestibular therapies.

The Impact of Comorbidities in the Aging Population on Cochlear Implant Outcomes.

OBJECTIVES: Cochlear implants have been used for many years for bilateral profound hearing loss. General longevity has continued to increase and, therefore, the age at which cochlear implants are placed has concomitantly increased. Our purpose is to determine whether outcomes and complications are significantly different in the elderly. STUDY DESIGN: Retrospective, clinical review. SETTING: Tertiary referral center, primarily ambulatory setting. PATIENTS: One hundred and one patients with moderate-to-profound hearing loss who ranged in age from 18 to 89 years. Subjects were divided into younger (<69, n = 51) and older (>70, n = 50) groups for analysis. INTERVENTION: All patients received either a unilateral or bilateral multichannel cochlear implant. The change in hearing in noise testing and AZBio testing between pre and postimplantation was evaluated in each group. MAIN OUTCOME MEASURES: Primary outcome measures include preimplant and postimplant hearing in noise test (HINT) and/or AZBio speech perception testing. Preimplant HINT/AZBio was compared with postimplant HINT/AZBio for each patient and between the two groups. In addition, we reviewed the comorbidities between the two groups as well as complication rates between less than 70 and more than 70 group. RESULTS: Both the younger and the older group demonstrated a significant improvement in postimplant HINT and/or AZBio scores. No statistically significant difference was noted in precochlear implant HINT/AZBio testing (p = 0.65/p = 0.48) between the two groups or the postimplant HINT/AZBio testing (p = 0.19/p = 0.22) between the two groups. Although, more than 70 yo group had significantly more comorbidities, the complication rates between the groups were insignificant. There was no shown association of specific comorbidities to complications between the two groups. CONCLUSIONS: Both older and younger patients can receive a significant improvement in speech perception with cochlear implantation. Older patients tend to have more comorbidities compared with the younger patients, however, the complication rates are not higher in this population.

The role of sphingosine-1-phosphate in endothelial barrier function.

Loss of endothelial barrier function is implicated in the etiology of metastasis, atherosclerosis, sepsis and many other diseases. Studies suggest that sphingosine-1-phosphate (S1P), particularly HDL-bound S1P (HDL-S1P) is essential for endothelial barrier homeostasis and that HDL-S1P may be protective against the loss of endothelial barrier function in disease. This review summarizes evidence providing mechanistic insights into how S1P maintains endothelial barrier function, highlighting the recent findings that implicate the major S1P carrier, HDL, in the maintenance of the persistent S1P-signaling needed to maintain endothelial barrier function. We review the mechanisms proposed for HDL maintenance of persistent S1P-signaling, the evidence supporting these mechanisms and the remaining fundamental questions.

Transcriptomes and shRNA suppressors in a TP53 allele-specific model of early-onset colon cancer in African Americans.

UNLABELLED: African Americans are disproportionately affected by early-onset, high-grade malignancies. A fraction of this cancer health disparity can be explained by genetic differences between individuals of African or European descent. Here the wild-type Pro/Pro genotype at the TP53Pro72Arg (P72R) polymorphism (SNP: rs1042522) is more frequent in African Americans with cancer than in African Americans without cancer (51% vs. 37%), and is associated with a significant increase in the rates of cancer diagnosis in African Americans. To test the hypothesis that Tp53 allele-specific gene expression may contribute to African American cancer disparities, TP53 hemizygous knockout variants were generated and characterized in the RKO colon carcinoma cell line, which is wild type for TP53 and heterozygous at the TP53Pro72Arg locus. Transcriptome profiling, using RNAseq, in response to the DNA-damaging agent etoposide revealed a large number of Tp53-regulated transcripts, but also a subset of transcripts that were TP53Pro72Arg allele specific. In addition, a shRNA-library suppressor screen for Tp53 allele-specific escape from Tp53-induced arrest was performed. Several novel RNAi suppressors of Tp53 were identified, one of which, PRDM1ß (BLIMP-1), was confirmed to be an Arg-specific transcript. Prdm1ß silences target genes by recruiting H3K9 trimethyl (H3K9me3) repressive chromatin marks, and is necessary for stem cell differentiation. These results reveal a novel model for African American cancer disparity, in which the TP53 codon 72 allele influences lifetime cancer risk by driving damaged cells to differentiation through an epigenetic mechanism involving gene silencing. IMPLICATIONS: TP53 P72R polymorphism significantly contributes to increased African American cancer disparity.

Cubilin maintains blood levels of HDL and albumin.

Cubilin is an endocytic receptor highly expressed in renal proximal tubules, where it mediates uptake of albumin and filtered forms of apoA-I/HDL. Cubilin deficiency leads to urinary loss of albumin and apoA-I; however, the consequences of cubilin loss on the homeostasis of blood albumin and apoA-I/HDL have not been studied. Using mice heterozygous for cubilin gene deletion (cubilin HT mice), we show that cubilin haploinsufficiency leads to reduced renal proximal tubular uptake of albumin and apoA-I and significantly increased urinary loss of albumin and apoA-I. Moreover, cubilin HT mice displayed significantly decreased blood levels of albumin, apoA-I, and HDL. The levels of albumin and apoA-I protein or mRNA expressed in the liver, kidney, or intestine of cubilin HT mice did not change significantly. The clearance rate of small HDL3 particles (density>1.13 g/ml) from the blood increased significantly in cubilin HT mice. In contrast, the rate of clearance of larger HDL2 particles from the blood did not change significantly, indicating a decreased half-life for HDL particles capable of filtering through the glomerulus. On the basis of these findings, we conclude that cubilin deficiency reduces renal salvage and delivery back to the blood of albumin and apoA-I, which decreases blood levels of albumin and apoA-I/HDL. These findings raise the possibility that therapeutic increase of renal cubilin expression might reduce proteinuria and increase blood levels of albumin and HDL.

Somatic mutations, allele loss, and DNA methylation of the Cub and Sushi Multiple Domains 1 (CSMD1) gene reveals association with early age of diagnosis in colorectal cancer patients.

BACKGROUND: The Cub and Sushi Multiple Domains 1 (CSMD1) gene, located on the short arm of chromosome 8, codes for a type I transmembrane protein whose function is currently unknown. CSMD1 expression is frequently lost in many epithelial cancers. Our goal was to characterize the relationships between CSMD1 somatic mutations, allele imbalance, DNA methylation, and the clinical characteristics in colorectal cancer patients. METHODS: We sequenced the CSMD1 coding regions in 54 colorectal tumors using the 454FLX pyrosequencing platform to interrogate 72 amplicons covering the entire coding sequence. We used heterozygous SNP allele ratios at multiple CSMD1 loci to determine allelic balance and infer loss of heterozygosity. Finally, we performed methylation-specific PCR on 76 colorectal tumors to determine DNA methylation status for CSMD1 and known methylation targets ALX4, RUNX3, NEUROG1, and CDKN2A. RESULTS: Using 454FLX sequencing and confirming with Sanger sequencing, 16 CSMD1 somatic mutations were identified in 6 of the 54 colorectal tumors (11%). The nonsynonymous to synonymous mutation ratio of the 16 somatic mutations was 15:1, a ratio significantly higher than the expected 2:1 ratio (p = 0.014). This ratio indicates a presence of positive selection for mutations in the CSMD1 protein sequence. CSMD1 allelic imbalance was present in 19 of 37 informative cases (56%). Patients with allelic imbalance and CSMD1 mutations were significantly younger (average age, 41 years) than those without somatic mutations (average age, 68 years). The majority of tumors were methylated at one or more CpG loci within the CSMD1 coding sequence, and CSMD1 methylation significantly correlated with two known methylation targets ALX4 and RUNX3. C:G>T:A substitutions were significantly overrepresented (47%), suggesting extensive cytosine methylation predisposing to somatic mutations. CONCLUSIONS: Deep amplicon sequencing and methylation-specific PCR reveal that CSMD1 alterations can correlate with earlier clinical presentation in colorectal tumors, thus further implicating CSMD1 as a tumor suppressor gene.

Sphingosine 1-phosphate (S1P) carrier-dependent regulation of endothelial barrier: high density lipoprotein (HDL)-S1P prolongs endothelial barrier enhancement as compared with albumin-S1P via effects on levels, trafficking, and signaling of S1P1.

Sphingosine 1-phosphate (S1P) is a blood-borne lysosphingolipid that acts to promote endothelial cell (EC) barrier function. In plasma, S1P is associated with both high density lipoproteins (HDL) and albumin, but it is not known whether the carriers impart different effects on S1P signaling. Here we establish that HDL-S1P sustains EC barrier longer than albumin-S1P. We showed that the sustained barrier effects of HDL-S1P are dependent on signaling by the S1P receptor, S1P1, and involve persistent activation of Akt and endothelial NOS (eNOS), as well as activity of the downstream NO target, soluble guanylate cyclase (sGC). Total S1P1 protein levels were found to be higher in response to HDL-S1P treatment as compared with albumin-S1P, and this effect was not associated with increased S1P1 mRNA or dependent on de novo protein synthesis. Several pieces of evidence indicate that long term EC barrier enhancement activity of HDL-S1P is due to specific effects on S1P1 trafficking. First, the rate of S1P1 degradation, which is proteasome-mediated, was slower in HDL-S1P-treated cells as compared with cells treated with albumin-S1P. Second, the long term barrier-promoting effects of HDL-S1P were abrogated by treatment with the recycling blocker, monensin. Finally, cell surface levels of S1P1 and levels of S1P1 in caveolin-enriched microdomains were higher after treatment with HDL-S1P as compared with albumin-S1P. Together, the findings reveal S1P carrier-specific effects on S1P1 and point to HDL as the physiological mediator of sustained S1P1-PI3K-Akt-eNOS-sGC-dependent EC barrier function.

Reduction in postoperative high-density lipoprotein cholesterol levels in children undergoing the Fontan operation.

Despite the emerging relevance of high-density lipoprotein (HDL) in the inflammatory cascade and vascular barrier integrity, HDL levels in children undergoing cardiac surgery are unexplored. As a measure of HDL levels, the HDL-cholesterol (HDL-C) in single-ventricle patients was quantified before and after the Fontan operation, and it was determined whether relationships existed between the duration and the type of postoperative pleural effusions. The study prospectively enrolled 12 children undergoing the Fontan operation. Plasma HDL-C levels were measured before and after cardiopulmonary bypass. The outcome variables of interest were the duration and type of chest tube drainage (chylous vs. nonchylous). The Kendall rank correlation coefficient and the Wilcoxon rank sum test were used. There were 11 complete observations. The median preoperative HDL-C level for all the subjects was 30 mg/dl (range, 24-53 mg/dl), and the median postcardiopulmonary bypass level was 21 mg/dl (range, 14-46 mg/dl) (p = 0.004). There was a tendency toward a moderate inverse correlation (-0.42) between the postcardiopulmonary bypass HDL-C level and the duration of chest tube drainage, but the result was not statistically significant (p = 0.07). In the chylous effusion group, the median postcardiopulmonary bypass HDL-C tended to be lower (16 vs. 23 mg/dl; p = 0.09). After the Fontan operation, the plasma HDL-C levels in children are significantly reduced. It is reasonable to conclude that the reduction in HDL-C reflects reduced plasma levels of HDL particles, which may have pertinent implications in postoperative pleural effusions given the antiinflammatory and endothelial barrier functions of HDL.

Impact of Nissen fundoplication on laryngopharyngeal reflux symptoms.

The reliability of Nissen fundoplication for the successful treatment of laryngopharyngeal reflux (LPR) symptoms remains in question. The purpose of this study was to assess the effect that antireflux surgery has on a variety of LPR symptoms as well as the patient's perceived success of surgical intervention. A retrospective review of all antireflux surgeries between 1998 and 2008 provided a patient base for a survey in which patients ranked pre- and postoperative LPR symptoms in addition to patient satisfaction with the outcome. Of the 611 patients identified and sent the evaluation forms, 244 responses (40%) were obtained. The percentage of patients with symptom improvement after surgery were: heartburn (90.1%), regurgitation (92.6%), voice fatigue (75.2%), chronic cough (76.3%), choking episodes (83.1%), sore throat (82.9%), lump in throat (77.4%), repetitive throat clearing (72.8%), and adult-onset asthma (59.6%). Twenty per cent with repetitive throat clearing and 30 per cent with adult-onset asthma had no improvement in symptoms. Eighty-one per cent considered surgery to be a success. Comparison of those who claimed the operation was successful with those who claimed it was not revealed no difference in demographics, primary diagnosis, procedure type, or reflux symptom index score. There was a statistically significant difference in patient-perceived outcome according to the length of time since surgery. More than 88 per cent in the "not successful" group had an operation greater than 4 years prior as compared with only 70 per cent in the "successful" group (P = 0.020). Nissen fundoplication is an effective treatment for most LPR symptoms, although patients with adult-onset asthma and repetitive throat clearing appear to benefit least from surgical intervention.

S1P, dihydro-S1P and C24:1-ceramide levels in the HDL-containing fraction of serum inversely correlate with occurrence of ischemic heart disease.

BACKGROUND: The lysosphingolipid sphingosine 1-phosphate (S1P) is carried in the blood in association with lipoproteins, predominantly high density lipoproteins (HDL). Emerging evidence suggests that many of the effects of HDL on cardiovascular function may be attributable to its S1P cargo. METHODS: Here we have evaluated how levels of S1P and related sphingolipids in an HDL-containing fraction of human serum correlate with occurrence of ischemic heart disease (IHD). To accomplish this we used liquid chromatography-mass spectrometry to measure S1P levels in the HDL-containing fraction of serum (depleted of LDL and VLDL) from 204 subjects in the Copenhagen City Heart Study (CCHS). The study group consisted of individuals having high serum HDL cholesterol (HDL-C) (females:≥ 73.5 mg/dL; males:≥ 61.9 mg/dL) and verified IHD; subjects with high HDL-C and no IHD; individuals with low HDL-C (females:≤ 38.7 mg/dL; males:≤ 34.1 mg/dL) and IHD, and subjects with low HDL-C and no IHD. RESULTS: The results show a highly significant inverse relationship between the level of S1P in the HDL-containing fraction of serum and the occurrence of IHD. Furthermore, an inverse relationship with IHD was also observed for two other sphingolipids, dihydro-S1P and C24:1-ceramide, in the HDL-containing fraction of serum. Additionally, we demonstrated that the amount of S1P on HDL correlates with the magnitude of HDL-induced endothelial cell barrier signaling. CONCLUSIONS: These findings indicate that compositional differences of sphingolipids in the HDL-containing fraction of human serum are related to the occurrence of IHD, and may contribute to the putative protective role of HDL in IHD.

Sphingosine-1-phosphate signaling in vasculogenesis and angiogenesis.

Blood vessels either form de novo through the process of vasculogenesis or through angiogenesis that involves the sprouting and proliferation of endothelial cells in pre-existing blood vessels. A complex interactive network of signaling cascades downstream from at least three of the nine known G-protein-coupled sphingosine-1-phosphate (S1P) receptors act as a prime effector of neovascularization that occurs in embryonic development and in association with various pathologies. This review focuses on the current knowledge of the roles of S1P signaling in vasculogenesis and angiogenesis, with particular emphasis on vascular cell adhesion and motility responses.