Outcomes of Patients with Opioid-Related Diagnoses in Acute Coronary Syndrome: a National Inpatient Sample-Based Analysis.

BACKGROUND: Acute coronary syndrome (ACS) and opioid use are both major causes of morbidity and mortality globally. Although epidemiological studies point to increased risk of ACS in opioid users, in-hospital management and outcomes are unknown for this population when presenting with ACS. We sought to determine whether there are differences for in-hospital outcomes and management of ACS for those with and without opioid-related diagnoses (ORD). METHODS AND RESULTS: From the National Inpatient Sample database, we extracted patients hospitalized between 2012 and 2016 for ACS. The primary independent variable was ORD by International Classification of Diseases, 9th and 10th Revision, codes. The primary outcome was in-hospital mortality; secondary outcomes were cardiac arrest, receipt of angiogram, and percutaneous coronary intervention (PCI). Statistical comparisons were performed using χ2 test and Student's t test. Multivariable logistic regression was performed to determine the independent association between ORD and outcomes of interest. Among the estimated 5.8 million admissions for ACS, the proportion of patients with ORD increased over the study period (p for trend < 0.01). Compared to patients without ORD presenting with ACS, patients with ORD were younger with fewer cardiovascular risk factors. Yet, in-hospital mortality was higher in patients with ORD presenting with ACS (AOR 1.36, 95% CI 1.26-1.48). Patients with ORD were more likely to experience in-hospital cardiac arrest (AOR 1.42, 95% CI 1.23-1.63) and less likely to undergo angiogram (AOR 0.42, 95% CI 0.38-0.45) or PCI (AOR 0.30, 95% CI 0.28-0.32). CONCLUSION: Despite evidence of increased risk of mortality and cardiac arrest, patients with ORD admitted for ACS are less likely to receive ACS management.

Usefulness of computed tomography to predict residual mitral regurgitation after transcatheter mitral valve edge-to-edge repair.

BACKGROUND: Multidetector computed tomography (MDCT) can provide valuable information for preprocedural planning of transcatheter mitral valve interventions. However, no data exist on MDCT parameters predicting residual mitral regurgitation (MR) post-MitraClip (Abbott Laboratories, Abbott Park, IL, USA). METHODS: We analyzed preprocedural MDCTs of 78 consecutive patients with secondary MR undergoing MitraClip implantation at our institution. Moderate-or-severe mitral leaflet calcification (MLC) was defined as calcification, with-or-without mitral annular calcification, extending beyond the mitral leaflet base. Residual MR was assessed by postprocedural transesophageal echocardiography, and clinical outcomes were assessed at 1-year. RESULTS: Fifteen patients (19 %) had residual MR ≥2+. Compared to patients with none-or-mild residual MR, MDCT-derived mitral valve orifice area (MVOA) to mitral annulus area (MAA) ratio was significantly lower (0.32 ±â€¯0.06 vs. 0.39 ±â€¯0.09; p = 0.003), and the prevalence of MLC was higher (40 % vs. 18 %; p = 0.057) in those with residual MR ≥2+. Furthermore, the MVOA/MAA ratio and MLC were independent predictors of residual MR ≥2+ post-MitraClip [adjusted odds ratio (ORadj): 0.88 (0.80-0.97) and 5.50 (1.16-26.23), respectively]. On receiver-operating-characteristic-curve analysis, MVOA/MAA ratio <0.31 had a sensitivity of 87 % and a specificity of 60 % for residual MR ≥2+. When patients were classified according to the presence of MLC and an MVOA/MAA ratio <0.31, those with both parameters had significantly higher rates of postprocedural residual MR ≥2+ and mitral reintervention at 1-year than those with only one, and those without both parameters. CONCLUSIONS: In patients with secondary MR undergoing the MitraClip procedure, preprocedural MDCT parameters, specifically MVOA/MAA ratio and MLC, are useful to predict postprocedural residual MR.

Outcomes of mechanical circulatory support for acute myocardial infarction complicated by cardiogenic shock.

BACKGROUND: Mechanical circulatory support (MCS) with the Impella device (Abiomed, Danvers, MA) has been associated with higher in-hospital mortality than intra-aortic balloon pump (IABP) in the Premier Healthcare Database and National Cardiovascular Data Registry. METHODS: The objective of this retrospective cohort study was to describe trends and outcomes of Impella usage in acute myocardial infarction complicated by cardiogenic shock (AMICS) treated with MCS (Impella or IABP) using real-world observational data from the National Inpatient Sample (NIS) including hospitalizations for AMICS managed with MCS between January 2012 to December 2017. The primary outcomes included in-hospital mortality, transfusion, acute kidney injury, stroke, total costs, and length of stay. Propensity score matching was performed with hierarchical models using risk factor and Elixhauser comorbidity variables. RESULTS AND CONCLUSION: We identified 54,480 hospitalizations for AMICS managed with MCS including 5750 (10.5%) utilizing Impella. Throughout the study period, Impella usage increased yearly to 19.9% of AMICS cases in 2017. After propensity score matching, Impella was associated with higher in-hospital mortality (odds ratio [OR] 1.74, 95% confidence interval [CI] 1.41-2.13) and transfusions (OR 1.97, 95% CI 1.40-2.78) than IABP, without association with acute kidney injury or stroke. Impella use was associated with higher hospital costs (mean difference $22,416.80 [95% CI $17,029-27,804]). Impella usage for AMICS increased significantly from 2012 to 2017 and was associated with increased in-hospital mortality and costs. Randomized controlled trials are urgently needed to assess the safety and efficacy of Impella.

Machine-Learning-Based In-Hospital Mortality Prediction for Transcatheter Mitral Valve Repair in the United States.

BACKGROUND: Transcatheter mitral valve repair (TMVR) utilization has increased significantly in the United States over the last years. Yet, a risk-prediction tool for adverse events has not been developed. We aimed to generate a machine-learning-based algorithm to predict in-hospital mortality after TMVR. METHODS: Patients who underwent TMVR from 2012 through 2015 were identified using the National Inpatient Sample database. The study population was randomly divided into a training set (n = 636) and a testing set (n = 213). Prediction models for in-hospital mortality were obtained using five supervised machine-learning classifiers. RESULTS: A total of 849 TMVRs were analyzed in our study. The overall in-hospital mortality was 3.1%. A naïve Bayes (NB) model had the best discrimination for fifteen variables, with an area under the receiver-operating curve (AUC) of 0.83 (95% CI, 0.80-0.87), compared to 0.77 for logistic regression (95% CI, 0.58-0.95), 0.73 for an artificial neural network (95% CI, 0.55-0.91), and 0.67 for both a random forest and a support-vector machine (95% CI, 0.47-0.87). History of coronary artery disease, of chronic kidney disease, and smoking were the three most significant predictors of in-hospital mortality. CONCLUSIONS: We developed a robust machine-learning-derived model to predict in-hospital mortality in patients undergoing TMVR. This model is promising for decision-making and deserves further clinical validation.

Seasonal variation in U.S. hospitalizations for chronic limb-threatening ischemia.

BACKGROUND: Seasonal variation in coronary artery disease is well described, with a peak in the winter and a trough in the summer. However, little is known about seasonal trends in hospital admission for critical limb-threatening ischemia (CLTI) and associated outcomes. METHODS: Patients admitted with CLTI from January 1, 2012 through August 31, 2015 were identified in the Healthcare Cost and Utilization Project's National Inpatient Sample based upon administrative claims diagnosis codes. The primary outcome was seasonal hospitalization incidence, and secondary outcomes included mortality rates and rates of in-hospital major and minor amputations among nondiabetics and diabetics. RESULTS: Of 1,276,745 hospitalizations for CLTI during the study period, 28.3% occurred in the spring, the peak admission season, and 19.1% occurred in the fall, the nadir. In-hospital mortality was highest during the winter (adjusted odds ratio [OR]: 1.08; 95% confidence interval [CI]: 1.03-1.14), and followed the highest seasonal rates of influenza in the fall; however, other important comorbidities did not differ significantly by season. For the overall cohort, there was no significant seasonal variation in rates of major or minor amputation, although seasonal rates were different according to diabetic status. Patients without diabetes had the highest odds of amputation in the spring (OR 1.07; 95% CI: 1.02-1.12), although this trend was not identified among patients with diabetes. CONCLUSIONS: There is significant seasonal variability in CLTI admissions and mortality but minimal variability in amputation rates. Understanding the seasonal variation in CLTI may help to identify individuals at greatest risk for hospitalization and death through patient and provider education efforts.

Frequency of Management of Cardiogenic Shock With Mechanical Circulatory Support Devices According to Race.

Mechanical circulatory support (MCS) has influenced the management of cardiogenic shock (CS), but the association between race and MCS utilization is unknown. We sought to evaluate the effect of race on MCS utilization in CS and whether there are racial differences in in-hospital outcomes. Our study was a population-based retrospective cohort study that enrolled patients with CS, defined by International classification of disease, ninth Revision, clinical modification (ICD-9-CM) codes, between 2013 and 2015 from the National Inpatient Sample. Race was adjudicated by National Inpatient Sample and included White, Black, Hispanic, Asian, and Native American. The primary outcomes were the utilization of MCS devices in CS with and without acute myocardial infarction (AMI), and in-hospital mortality by race. The statistical adjustment was performed for clinical co-morbidities as well as in-hospital events using multivariate logistic regressions. Among 332,885 patients with CS, there were 71% white and 14% black patients, and AMI was present in 42% and MCS was utilized in 23% of patients. There was less utilization of MCS only in Black patients with CS, and with AMI after adjustment (odds ratio [OR] 0.84, 95% confidence interval [CI][0.79 to 0.89] and OR 0.85, 95% CI 0.78 to 0.92, respectively). In addition, only Black patients had greater in-hospital mortality in AMI after adjustment (OR 1.16, 95% CI [1.06 to 1.27]) whereas there was no statistically significant increase in in-hospital mortality in any other race. In conclusion, these results suggest that there is less utilization of MCS devices and, in parallel, increased odds of in-hospital mortality in Black patients in comparison to other races. Further steps may be needed to address possible implicit bias in acute clinical scenarios as new devices emerge, which carries new opportunities to improve clinical outcomes but there is a lack of clear guidelines.

Machine Learning Prediction Models for In-Hospital Mortality After Transcatheter Aortic Valve Replacement.

OBJECTIVES: This study sought to develop and compare an array of machine learning methods to predict in-hospital mortality after transcatheter aortic valve replacement (TAVR) in the United States. BACKGROUND: Existing risk prediction tools for in-hospital complications in patients undergoing TAVR have been designed using statistical modeling approaches and have certain limitations. METHODS: Patient data were obtained from the National Inpatient Sample database from 2012 to 2015. The data were randomly divided into a development cohort (n = 7,615) and a validation cohort (n = 3,268). Logistic regression, artificial neural network, naive Bayes, and random forest machine learning algorithms were applied to obtain in-hospital mortality prediction models. RESULTS: A total of 10,883 TAVRs were analyzed in our study. The overall in-hospital mortality was 3.6%. Overall, prediction models' performance measured by area under the curve were good (>0.80). The best model was obtained by logistic regression (area under the curve: 0.92; 95% confidence interval: 0.89 to 0.95). Most obtained models plateaued after introducing 10 variables. Acute kidney injury was the main predictor of in-hospital mortality ranked with the highest mean importance in all the models. The National Inpatient Sample TAVR score showed the best discrimination among available TAVR prediction scores. CONCLUSIONS: Machine learning methods can generate robust models to predict in-hospital mortality for TAVR. The National Inpatient Sample TAVR score should be considered for prognosis and shared decision making in TAVR patients.

Qualitative Assessment of Color M-Mode Signals in the Evaluation of Left Ventricular Diastolic Function: A Proof of Concept Study.

OBJECTIVES: Although the most recent American Society of Echocardiography guidelines are a major step forward in echocardiographic evaluation of diastolic function, the ability to differentiate between normal and abnormal function remains challenging. The authors aimed to determine whether qualitative assessments of color M-mode flow displays could be a useful parameter in the evaluation of left ventricular (LV) diastolic dysfunction. DESIGN: Retrospective observational study. SETTING: Tertiary care level hospital. PARTICIPANTS: The study comprised echocardiographic data from 105 consecutive patients. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: Patients were allocated into the following 3 groups according to the LV diastolic function based on current American Society of Echocardiography recommendation guidelines for LV diastolic dysfunction classification: group I-normal function (n = 40); group II-early relaxation abnormalities (grade I) (n = 50), and group III-elevated LV pressures (grade II) (n = 15). Patients with normal diastolic function were younger (45 ± 14 y) than those with diastolic dysfunction (group II: 64 ± 10 y and group III: 56 ± 15 y) (p < 0.05). Volumetric echocardiographic parameters and mitral inflow and mitral annulus tissue Doppler imaging measures were significantly different among the 3 studied groups (p < 0.05). Interestingly, qualitative assessment of color M-mode flows displayed distinctive signals based on the left ventricle filling properties. Intraobserver and interobserver variability to determine the reliability of these signals were robust (weighted kappa 0.84 ± 0.11 and 0.65 ± 0.13, respectively). CONCLUSION: Qualitative assessment of color M-mode flow displays offers simple and reliable information of potential usefulness in the evaluation of LV diastolic function.

Patient Ethnicity Predicts Poor Health Access and Gaps in Perception of Personal Cardiovascular Risk Factors.

BACKGROUND: Focus of health literacy campaigns has centered around raising awareness. It is unknown whether awareness of coronary artery disease risk factors accurately reflects personalization of one's own cardiovascular risk. METHODS: A cross-sectional survey was performed in consecutive patients presenting with chest pain admitted to an observation unit of a tertiary care hospital. A 32-item questionnaire in English or Spanish examined knowledge of coronary artery disease risk factors. Separately, the personalization of coronary risk factors was determined by having patients list their individual risk factors for having a heart attack. Primary outcome was the evaluation of ethnic disparities in awareness of cardiovascular risk factors and the patient's misperceptions on personal risk factors. Secondary outcome was the assessment of access to information in the same population by gender and ethnicity. RESULTS: Between October 2006 and April 2008, 1584 consecutive patients were screened, and 1051 patients were enrolled. Participants were 57.5% female and 62.8% self-identified White, 22.5% Black, and 11.5% Hispanic. Misperception about personal risk was significantly higher in non-White compared with the White participants for diabetes (in Blacks [odds ratio (OR), 2.22; 95% confidence interval (CI), 1.08-5.57] and Hispanics [OR, 3.50; 95% CI, 1.49-8.20]) and for hyperlipidemia (in Hispanics [OR, 2.21; 95% CI, 1.19-4.10]). Although the majority (85%) had a primary care physician, Blacks and Hispanics were less likely to have access to information (OR, 0.25; 95% CI, 0.10-0.49; and OR, 0.71; 95% CI, 0.37-1.04, respectively). CONCLUSIONS: There are major gaps between awareness and personalization of risk in major modifiable coronary artery disease risk factors in different ethnic groups.

Depression is associated with recurrent chest pain with or without coronary artery disease: A prospective cohort study in the emergency department.

BACKGROUND: Only a small fraction of acute chest pain in the emergency department (ED) is due to obstructive coronary artery disease (CAD). ED chest pain remains associated with high rates of recidivism, often in the presence of nonobstructive CAD. Psychological states such as depression, anxiety, and elevation of perceived stress may account for this finding. The objective of the study was to determine whether psychological states predict recurrent chest pain (RCP). METHODS: We conducted a prospective cohort study of low- to moderate-cardiac risk ED patients admitted to the Yale Chest Pain Center with acute chest pain. Depression, anxiety, and perceived stress were assessed in each patient using multistudy-validated screening scales: Patient Health Questionnaire (PHQ8), Clinical Anxiety Scale (CAS), and Perceived Stress Scale (PSS), respectively. All patients ruled out for infarction underwent appropriate cardiac stress testing. Primary outcome was RCP at 30 days evaluated by phone follow-up and medical record. The relationship between each psychological scale and RCP was evaluated using ordinal logistic regressions, controlling for known sociodemographic and cardiac risk factors. Depression (PHQ8≥10), anxiety (CAS≥30), and perceived stress (PSS≥15) were considered positive. RESULTS: Between August 2013 and May 2015, 985 patients were screened at the Yale Chest Pain Center. Of 500 enrolled patients, 483 patients had complete data and 365 (76%) patients completed follow-up. Thirty-six percent (n=131) had RCP within 1 month. On multivariable regression models, depression (odds ratio [OR]=2.11, 95% CI 1.18-3.79) was a significant independent predictor of 30-day chest pain recurrence after adjustment, whereas PSS (OR=0.96, 95% CI 0.60-1.53) and anxiety (OR=1.59, 95% CI 0.80-3.20) were not. Similarly, there was a direct relationship between psychometric evaluation of depression (via PHQ8) and the frequency of chest pain. CONCLUSIONS: Depression is independently associated with RCP regardless of significant cardiac ischemia on stress testing. Identification and targeted interventions may curtail recidivism with RCP.

Is Isolated Low High-Density Lipoprotein Cholesterol a Cardiovascular Disease Risk Factor? New Insights From the Framingham Offspring Study.

BACKGROUND: Although the inverse association between high-density lipoprotein cholesterol (HDL-C) and risk of cardiovascular disease (CVD) has been long established, it remains unclear whether low HDL-C remains a CVD risk factor when levels of low-density lipoprotein cholesterol (LDL-C) and triglycerides (TG) are not elevated. This is a timely issue because recent studies have questioned whether HDL-C is truly an independent predictor of CVD. METHODS AND RESULTS: 3590 men and women from the Framingham Heart Study offspring cohort without known CVD were followed between 1987 and 2011. Low HDL-C (<40 mg/dL in men and <50 mg/dL in women) was defined as isolated if TG and LDL-C were both low (<100 mg/dL). We also examined higher thresholds for TG (150 mg/dL) and LDL-C (130 mg/dL) and compared low versus high HDL-C phenotypes using logistic regression analysis to assess association with CVD. Compared with isolated low HDL-C, CVD risks were higher when low HDL-C was accompanied by LDL-C ≥100 mg/dL and TG <100 mg/dL (odds ratio 1.3 [1.0, 1.6]), TG ≥100 mg/dL and LDL-C <100 mg/dL (odds ratio 1.3 [1.1, 1.5]), or TG and LDL-C ≥100 mg/dL (odds ratio 1.6, [1.2, 2.2]), after adjustment for covariates. When low HDL-C was analyzed with higher thresholds for TG (≥150 mg/dL) and LDL-C (≥130 mg/dL), results were essentially the same. In contrast, compared with isolated low HDL-C, high HDL-C was associated with 20% to 40% lower CVD risk except when TG and LDL-C were elevated. CONCLUSIONS: CVD risk as a function of HDL-C phenotypes is modulated by other components of the lipid panel.

Relation of Vitamin E and Selenium Exposure to Prostate Cancer Risk by Smoking Status: A Review and Meta-Analysis.

BACKGROUND: Epidemiological studies of selenium and vitamin E, two antioxidants hypothesized to reduce prostate cancer risk, have shown no discernible benefit. It has been proposed, however, that tobacco smoking may modify the effect of these nutrients. MATERIALS AND METHODS: We performed a meta-analysis of studies evaluating the relation of vitamin E and selenium exposure to prostate cancer risk in never smokers vs. ever smokers and, when feasible, former and current smokers. Overall and stratum-specific meta-risk ratios (meta-RRs) and 95% confidence intervals (CIs) were calculated using random-effects models. RESULTS: A total of 21 studies have met the inclusion criteria. Meta-RR (95% CI) estimates of prostate cancer associated with vitamin E use were 1.03 (0.95-1.11) in never smokers and 0.98 (0.90-1.07) in ever-smokers. For selenium, meta-RRs were 1.09 (0.78-1.52 and 0.76 (0.60-0.96) for never and ever-smokers, respectively; however, results for current smokers were weaker than those for former smokers. Sub-analyses according to different exposure assessment methods and outcome definitions produced similar results across strata. CONCLUSION: The association between vitamin E and prostate cancer is not modified by smoking. Selenium exposure is associated with lower prostate cancer risk among ever-smokers; however, the lack of an association for current smokers indicates that this finding needs to be interpreted with caution.

Virally mediated Kcnq1 gene replacement therapy in the immature scala media restores hearing in a mouse model of human Jervell and Lange-Nielsen deafness syndrome.

Mutations in the potassium channel subunit KCNQ1 cause the human severe congenital deafness Jervell and Lange-Nielsen (JLN) syndrome. We applied a gene therapy approach in a mouse model of JLN syndrome (Kcnq1(-/-) mice) to prevent the development of deafness in the adult stage. A modified adeno-associated virus construct carrying a Kcnq1 expression cassette was injected postnatally (P0-P2) into the endolymph, which resulted in Kcnq1 expression in most cochlear marginal cells where native Kcnq1 is exclusively expressed. We also found that extensive ectopic virally mediated Kcnq1 transgene expression did not affect normal cochlear functions. Examination of cochlear morphology showed that the collapse of the Reissner's membrane and degeneration of hair cells (HCs) and cells in the spiral ganglia were corrected in Kcnq1(-/-) mice. Electrophysiological tests showed normal endocochlear potential in treated ears. In addition, auditory brainstem responses showed significant hearing preservation in the injected ears, ranging from 20 dB improvement to complete correction of the deafness phenotype. Our results demonstrate the first successful gene therapy treatment for gene defects specifically affecting the function of the stria vascularis, which is a major site affected by genetic mutations in inherited hearing loss.

Timed conditional null of connexin26 in mice reveals temporary requirements of connexin26 in key cochlear developmental events before the onset of hearing.

Mutations in the Gjb2 gene, which encodes a gap junction protein connexin26 (Cx26), are the most prevalent form of hereditary deafness in humans and represent about half of non-syndromic congenital deafness cases in many ethnic populations. Cochlear potassium (K+) recycling in mature cochlea is required for normal hearing. It is thought that gap junctions are essential for K+ recycling and that Gjb2 mutations cause Gjb2-associated deafness by disrupting K+ recycling in mature cochlea. Here we present evidence showing that Gjb2 is required for normal development of the neonatal organ of Corti prior to the onset of the hearing in mice. In the conditional Gjb2 null (cCx26 null) mice, ribbon synapses in inner hair cells remained poorly developed, the afferent type I fibers failed to finish the refinement process to form convergent innervation to individual inner hair cells. The spontaneous depolarizing activities in the supporting cells, which normally diminish in the wild type cochleae after postnatal day 8 (P8), remained strong in the cochlea after P8 in the mutant mice. Furthermore, the deafness phenotype was readily generated only if the Cx26 expression in the organ of Corti was significantly reduced before P6. Similar amount of Cx26 reduction in more mature cochleae had a much weaker effect in damaging the hearing sensitivity. Our findings indicated that Cx26 plays essential roles in the maturation process of the organ of Corti prior to the establishment of high K+ in the endolymph and the onset of hearing. These results suggest that successful treatment of Cx26 deafness requires early intervention before the cochlea fully matures.

Marked hypertriglyceridemia in a woman receiving metoprolol succinate.

ß-blockers are commonly used therapies after acute myocardial infarction and in the management of congestive heart failure and hypertension. We report a case of a middle-aged woman with a history of mild hypertension who was placed on metoprolol succinate. Before initiation of the ß-blocker, her triglyceride level was in the borderline-high range (150-199 mg/dL). On treatment, her triglyceride levels exceeded 1000 mg/dL. She developed fatigue and mild abdominal discomfort but without biochemical evidence of pancreatitis. After discontinuation of metoprolol succinate, her triglyceride levels receded. This case illustrates an uncommon side effect with a very commonly used therapy in clinical practice. Clinicians should closely evaluate medications and/or other therapies in patients presenting with new-onset hypertriglyceridemia especially when levels are sufficiently elevated to pose increased risk of pancreatitis.

Audiologic and genetic features of the A3243G mtDNA mutation.

BACKGROUND: Mitochondrial mutations have been shown to be responsible for syndromic and nonsyndromic hearing impairment. AIM: To assess the genotypic-phenotypic correlation of mitochondrial DNA mutations in three generations of a single family. METHODS: A single family with maternally inherited diabetes and hearing loss was recruited. Genomic DNA was subject to polymerase chain reaction-restriction fragment length polymorphism analysis (ApaI) for A3243G mutation detection and confirmation with direct DNA sequencing. The degree of heteroplasmy for the A3243G mutation in blood DNA samples was quantified. In addition, we reviewed audiological data of A3243G-associated hearing loss cases from the literature to provide details of audiologic features. RESULTS: Six of 11 family members were recruited. All affected members harbored the A3243G mutation. Four of six members had diabetes. Five of five affected members demonstrated hearing loss ranging from mild to severe. The degree of heteroplasmy ranged from 5.51% to 27.74%. CONCLUSIONS: Patients with a greater percentage of heteroplasmy have a trend toward more severe phenotypic presentations. Hearing loss is bilateral, sensorineural, and symmetric. The main audiogram shapes found were sloping. Additional studies are necessary to clarify the relationship between degree of heteroplasmy and phenotypic presentation.

Early postnatal virus inoculation into the scala media achieved extensive expression of exogenous green fluorescent protein in the inner ear and preserved auditory brainstem response thresholds.

BACKGROUND: Gene transfer into the inner ear is a promising approach for treating sensorineural hearing loss. The special electrochemical environment of the scala media raises a formidable challenge for effective gene delivery at the same time as keeping normal cochlear function intact. The present study aimed to define a suitable strategy for preserving hearing after viral inoculation directly into the scala media performed at various postnatal developmental stages. METHODS: We assessed transgene expression of green fluorescent protein (GFP) mediated by various types of adeno-associated virus (AAV) and lentivirus (LV) in the mouse cochlea. Auditory brainstem responses were measured 30 days after inoculation to assess effects on hearing. RESULTS: Patterns of GFP expression confirmed extensive exogenous gene expression in various types of cells lining the endolymphatic space. The use of different viral vectors and promoters resulted in specific cellular GFP expression patterns. AAV2/1 with cytomegalovirus promoter apparently gave the best results for GFP expression in the supporting cells. Histological examination showed normal cochlear morphology and no hair cell loss after either AAV or LV injections. We found that hearing thresholds were not significantly changed when the injections were performed in mice younger than postnatal day 5, regardless of the type of virus tested. CONCLUSIONS: Viral inoculation and expression in the inner ear for the restoration of hearing must not damage cochlear function. Using normal hearing mice as a model, we have achieved this necessary step, which is required for the treatment of many types of congenital deafness that require early intervention.

Characteristics of ethylnitrosourea-induced cataracts.

PURPOSE: This study analyzed genes associated with the morphology and regulation of ethylnitrosourea (ENU)-induced cataract mouse. MATERIALS AND METHODS: Immunohistochemistry analysis using anti-crystallins and PCNA antibody revealed that the localization pattern of these specific markers differed between the cataractous and wild-type lens epithelium. Two-dimensional electrophoresis and microarray techniques were used to identify the proteins and genes related to ENU-induced cataract. RESULTS: A novel ENU-induced mutation in the mouse led to nuclear and cortical opacity of the eye lens at 5 weeks postnatal. This cataract phenotype was similar to that of the zonular-pulverulent type of human cataract. Crystallin proteins and gap-junction genes have relations to the formation of cataract. CONCLUSIONS: Together, the results suggest that various proteins affect the formation and specific phenotypes of ENU-induced cataract mouse.

Shh and ROCK1 modulate the dynamic epithelial morphogenesis in circumvallate papilla development.

In rodents, a circumvallate papilla (CVP) develops with dynamic changes in epithelial morphogenesis during early tongue development. Molecular and cellular studies of CVP development revealed that there would be two different mechanisms in the apex and the trench wall forming regions with specific expression patterns of Wnt11 and Shh. Molecular interactions were examined using in vitro organ culture with over-expression of Shh, important signalling molecules and various inhibitors revealed that there are two significant different mechanisms in CVP formation by Wnt11 and Shh expressions. Wnt, a well known key molecule to initiate taste papillae, would govern Rho activation and cytoskeleton formation in the apex epithelium of CVP. In contrast, Shh regulates the cell proliferation to differentiate taste buds and to invaginate the epithelium for development of von Ebner's gland (VEG). Based on these results, we suggest that these different molecular signalling cascades of Wnt11 and Shh would play crucial roles in specific morphogenesis and pattern formation of CVP during early mouse embryo development.