Prevalence of otolaryngological disease in a refugee population compared to US-born patients.

Objective: Limited data exists regarding otolaryngological (ENT) disease in refugees and we aim to characterize its prevalence. Methods: This is a retrospective descriptive chart review of adult US-born, immigrant, and refugee patients receiving care at a primary care clinic between 2014 and 2017. We report the prevalence of ENT disease by immigration status. Bivariable and multivariable logistic regression models were conducted to assess differences in prevalence of ENT disease by immigration status. Results: Of 995 patients included, 202 US-born, 450 immigrants, and 343 were refugees. Immigrants were older (46 years vs. 34 years among refugees, 35.5 years among US-born, p < .001) and more likely to be women (64% vs. 52% among refugees and 56% among US-born, p = .003). Among refugees, 27% were Central American, 22% Chinese, and 9.3% Middle Eastern. Hearing loss and allergic rhinitis were the top two diagnoses among the three groups of immigration status. More refugees had at least 1 ENT diagnosis compared to the other groups (16% vs 14% among immigrants and 6% US-born, p < .001). Refugees were more likely to have at least 1 ENT diagnosis compared to US-born individuals (age and gender adjusted [aOR] 3.40, 95% CI [1.80-6.95], p < .001) and immigrants (aOR 1.62, [1.05-2.51], p = .03). Conclusion: ENT disease is prevalent among refugees, necessitating standardized evaluation during refugee health assessments and identifying barriers to referral and treatment. Level of evidence: 2b.

Predictors of successful natural sleep MRI for sensorineural hearing loss in infants.

OBJECTIVES: Cochlear implantation (CI) in children with sensorineural hearing loss (SNHL) before 12 months of age (mo) improves language outcomes. MRI is important to assess CI candidacy. Anesthesia before 3 years old may increase risk of neurocognitive delay. Natural sleep MRI (NS-MRI) is an emerging technique to avoid anesthesia in infants, but relies on successful sleep for adequate imaging. Our multidisciplinary team hypothesized the following predictors of successful NS-MRI for CI evaluation: age, distance travelled, comorbidities, primary language, insurance type, HL characteristics, time and duration of MRI. METHODS: We performed retrospective review of children 0-12mo who attempted NS-MRI. The NS-MRI was successful if imaging was sufficient for definitive clinical management per the managing otolaryngologist. RESULTS: Among 26 patients (29 scans), the median age was 3.2mo (range: 1.2-6.8mo), distance travelled was 16.3 miles (range: 0.9 to 365 miles), 12 (46%) children had medical comorbidities. 8 (31%) had public insurance. 10 (38%) had bilateral HL. 52% (15/29) of scans were successful. Patients with comorbidities had significantly lower odds of successful NS-MRI (OR 0.09; 95% CI 0.01-0.54). Success was not associated with age, distance travelled, insurance type, primary language, HL characteristics, time or duration of MRI on univariable analysis. All 11 children who failed NS-MRI underwent hearing-aid fitting and/or imaging with sedation and CI as clinically indicated before 12mo. CONCLUSION: NS-MRI was successful in 52% of infants, regardless of age, demographics, HL or MRI characteristics. Unsuccessful NS-MRI did not result in delayed intervention. NS-MRI is an effective consideration for a broad range of infants with SNHL.

Associations between demographic factors and pediatric otolaryngology access disparities in the COVID-19 era.

OBJECTIVES: To assess the impact of demographic factors and telehealth on access to pediatric otolaryngology care during the COVID-19 pandemic, as measured by attendance. METHODS: Retrospective, observational study of all referrals to pediatric otolaryngology at a single, tertiary care pediatric hospital system in the US. All referrals placed to pediatric otolaryngology from March through December 2020 were compared with referrals between March and December 2019. Data on patient demographics, date of referral, duration between referral and appointment, appointment type, and diagnosis acuity were collected. A multivariate linear regression was used to evaluate the impact of the patient age, ethnicity, language, insurance, diagnosis acuity, time to appointment, and appointment type on attendance. RESULTS: This study included 1988 referrals placed between March 16th-December 31st, 2020 and 3704 referrals placed between March 16th-December 31st, 2019. In 2020, attendance proportions were significantly higher at 72% compared to 62% during 2019 (p < 0.001). In 2020, there was a significantly shorter duration between referral and appointment, averaging 10 days as compared to 26 days in 2019 (p < 0.001). Overall, Black and Hispanic patients, children over the age of one, publicly insured patients, and those with longer wait times were less likely to attend their appointments. Primary language and use of telehealth did not predict attendance. CONCLUSION: Early evidence has found significant healthcare access and outcome disparities across ethnicities during the COVID pandemic. However, there is limited data evaluating the effect of demographic factors or telehealth on access to pediatric otolaryngology care. This study identifies age, race and insurance type as predictors of access to pediatric otolaryngologic care, as measured by attendance.

Racial and ethnic disparities in diagnostic efficacy of comprehensive genetic testing for sensorineural hearing loss.

Understanding racial and ethnic disparities in diagnostic rates of genetic testing is critical for health equity. We sought to understand the extent and cause of racial and ethnic disparities in diagnostic efficacy of comprehensive genetic testing (CGT) for sensorineural hearing loss (SNHL). We performed a retrospective cohort study at two tertiary children's hospitals on a diverse cohort of 240 consecutive pediatric patients (76% publicly insured, 82% non-White) with SNHL of unknown etiology who underwent CGT. Definite and possible genetic diagnoses were assigned for each patient, representing the likelihood of a genetic cause of hearing loss. Associations between diagnostic rates were examined. 3.8 ± 2.1 variants were detected per patient; this frequency did not vary between White/Asian and Hispanic/Black cohorts. Overall, 82% of variants were variants of uncertain significance (VUS). Compared with White and Asian subjects, variants identified among Hispanic and Black children were less likely to be classified as pathogenic/likely pathogenic (15% vs. 24%, p < 0.001), and Hispanic and Black children were less likely to have a definite genetic diagnosis (10% vs. 37%, p < 0.001). The adjusted odds ratio for definite genetic diagnosis in Black and Hispanic children compared with White and Asian children was 0.19. Expanding genetic diagnostic criteria to include predicted deleterious VUSs reduced these disparities between White/Asian and Hispanic/Black children, with comparable molecular diagnostic rates (41% vs. 38%, p = 0.72). However, in silico predictions are insufficiently valid for clinical use. Increased inclusion of underrepresented groups in genetic hearing-loss studies to clinically validate these variants is necessary to reduce racial and ethnic disparities in diagnostic efficacy of comprehensive genetic testing.

Efficacy of endoscopic sinus surgery alone versus in combination with neurosurgical intervention for the treatment of pediatric subdural empyema.

OBJECTIVES: To compare treatment outcomes for sinogenic subdural empyema (SE) between those managed with initial endoscopic sinus surgery (ESS) alone versus those treated with a combination of ESS and craniotomy over the last decade at our institution. To better characterize subdural empyema with regard to presentation, causative pathogens, and treatment course. METHODS: Retrospective single-center chart review to identify and evaluate pediatric SE patients between 2009 and 2019. Patients meeting inclusion criteria were classified in one of two groups: those who initially underwent ESS or frontal trephination without concurrent neurosurgical procedure and those who underwent craniotomy or burr hole in addition to a sinus procedure. Presenting characteristics and treatment outcomes were compared between the two groups. RESULTS: Eighteen patients met inclusion criteria. The ESS alone and the ESS + craniotomy subgroups each had 9 patients with similar baseline characteristics. The ESS + craniotomy group was more likely to present with neurological symptoms (p = 0.039) and have multiple intracranial fluid collections (p = 0.046). 74.1% of patients presented to the Emergency Department (ED) or to their primary medical doctor and were treated with outpatient management prior to hospitalization with definitive surgical management. The most common presenting symptoms were fever, headache and nausea/vomiting. There were no differences between treatment groups in rate of return to the operating room (OR) (p = 1.00), length of stay (LOS) (p = 0.553), or adverse neurological outcomes (p = 0.456). 44.4% of patients in the ESS alone group eventually required neurosurgical intervention. CONCLUSIONS: Surgical SE patients often present to medical professionals in the primary care setting or ED and are managed with outpatient treatment before admission with definitive treatment. In this small retrospective cohort patients who underwent sinus intervention alone had similar rates of return to OR, LOS and adverse neurological outcomes use as those who underwent a sinus procedure in coordination with a neurosurgical intervention. There may be a group of patients with SE who may be managed with endoscopic procedures alone and further studies should seek to determine the characteristics of this population.

Airway Hemangiomas in PHACE Syndrome: A Multicenter Experience.

OBJECTIVE: To describe the prevalence and clinical characteristics of airway findings in a multi-institutional cohort of PHACE patients. STUDY DESIGN: Multicenter retrospective case series. SETTING: Multidisciplinary vascular anomalies clinics at 2 institutions. METHODS: Data were collected from the electronic medical record, including clinical presentation, airway findings, treatment, and outcomes. RESULTS: Of 55 PHACE patients, 22 (40%) had airway hemangiomas. Patients with airway involvement were more commonly female (P = .034, odds ratio [OR] 23, 95% confidence interval [CI] 1.3-410) and of Caucasian ethnicity (P = .020, OR 5.3, 95% CI 1.3-21). Anatomically, patients with bilateral S3 involvement had higher rates of airway disease (P = .0012, OR 15, 95% CI 2.9-77). Most patients with airway hemangiomas had stridor (68%). Of the patients managed in the propranolol era (2008 or later, n = 35), 14 had airway involvement. All 14 were treated with propranolol, whereas 13 (62%) of 21 nonairway patients were treated with propranolol. The average treatment duration was longer in the airway patients (22.1 vs 16.7 months). All patients who underwent tracheostomy (n = 4) did so before 2008. CONCLUSION: Risk factors for airway involvement in PHACE include female gender, Caucasian ethnicity, and stridor. Since the widespread use of propranolol, fewer patients have required surgical management of their airway disease. Given the high prevalence of airway involvement even in patients without stridor, assessment of the airway is a crucial component of a comprehensive PHACE workup.

Association of Ebola Virus Infection With Hearing Loss in Regions Where Ebola Virus Infection Is Endemic: A Systematic Review.

Importance: Many survivors of Ebola virus infection describe new-onset hearing loss after infection. The prevalence, severity, and pathophysiologic features of hearing loss in this population have not been well characterized. Objective: To perform a systematic review of the current literature to characterize hearing loss in survivors of Ebola virus infection. Evidence Review: This study adhered to the relevant sections of the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline. Searches through PubMed, Embase, and Google Scholar were performed to include publications written in English from January 1, 1965, to October 1, 2018. Relevant vocabulary terms and key terms related to Ebola and hearing loss were used. Two investigators independently screened the eligible studies, extracted data, and assessed quality and risk of bias. Findings: Of 127 publications reviewed, 15 met the criteria for inclusion; 3 were retrospective case-control studies (level of evidence, 3), and 12 were cross-sectional studies or case reports (level of evidence, 4). Studies included 1775 survivors of Ebola virus infection (993 female [55.9%]) and 363 uninfected controls (186 female [51.2%]) from the Democratic Republic of the Congo, Uganda, Guinea, Liberia, and Sierra Leone. The duration of follow-up ranged from 0 to 29 months (median, 5 months). Hearing loss was reported in 147 survivors of Ebola virus infection (8.3%). Among studies that compared survivors with controls, the reported odds ratios for hearing loss in survivors was 7.50 (95% CI, 3.91-14.39; range, 1.4-12.1). Including all studies, the odds ratio of hearing loss in survivors vs controls in countries where Ebola virus infection is endemic was 1.84 (95% CI, 1.10-3.08). Conclusions and Relevance: Survivors of Ebola virus infection had higher rates of hearing loss than uninfected controls in regions where the infection is endemic. Further research with consistent objective methods and pure-tone audiometry may be needed to better characterize the hearing loss, understand its pathophysiologic features, and develop treatments.

Sirolimus for management of complex vascular anomalies - A proposed dosing regimen for very young infants.

Neonates with vascular anomalies causing airway compromise and other complications require early initiation of medical therapy. Sirolimus has emerged as a safe and effective treatment, but standard recommendations for dosing start at seven months. Guidelines are needed for dosing in very young infants, who have reduced hepatic metabolism of sirolimus. We present our experience treating six neonates (mean age 14.8 days) with complicated vascular anomalies. Standard dosing caused supratherapeutic levels in this population. Our modified dosing regimen has resulted in safe therapeutic concentrations. Properly dosed, sirolimus is a viable and potentially lifesaving option for neonates with severe morbidity from vascular anomalies.

Survival and Surgical Outcomes for Pediatric Head and Neck Melanoma.

Importance: Melanoma in children is rare, accounting for approximately 2% of all pediatric malignant neoplasms. However, for the past 30 years, the incidence of melanoma in those younger than 20 years has been increasing. Location of the primary tumor has been shown to be an important prognostic factor, with melanomas of the scalp and neck conferring a worse prognosis than those originating at other sites. Objective: To examine the survival, demographic, tumor, and treatment characteristics of pediatric head and neck melanoma. Design, Setting, and Participants: We performed a retrospective cohort study using information from the National Cancer Data Base from January 1, 1998, to December 31, 2012, on pediatric (≤18 years) and adult (>18 years) patients with head and neck melanoma. Data analysis was conducted from August 1, 2015, to June 30, 2016. Exposure: Pediatric age (≤18 years) at diagnosis of head and neck melanoma. Main Outcomes and Measures: Survival differences were estimated using a Cox proportional hazards regression model. Surgical outcomes, including nodal sampling and margin status, were estimated with generalized linear models comparing pediatric and adult patients. Patient demographic, tumor, and treatment characteristics were estimated using t tests and χ2 tests between pediatric and adult patients with head and neck melanoma for continuous and categorical data, respectively. Results: Of the 84 744 patients with head and neck melanoma, 657 (0.8%) were 18 years or younger (mean [SD] age, 13.5 [4.7] years; 285 female and 372 male; 610 white). Pediatric and adult patients had similar demographics but different histologic subtypes (risk difference of pediatric vs adult patients: melanoma, not otherwise specified, 8.5% [95% CI, 4.7%-12.3%]; superficial spreading, 4.2% [95% CI, 0.89%-7.4%]; and lentigo maligna, -13.4% [95% CI, -14.1% to 12.6%]). Pediatric patients had tumors of similar mean depth to those in adult patients (pediatric, 1.54 mm; adult; 1.39 mm; absolute difference, 0.15 mm; [95% CI, -0.32 to 0.008]) and more frequent nodal metastases than did adult patients (risk difference of pediatric vs adult patients for stage T2, 23.9% [95% CI, 14.1%-33.6%]). Five-year survival among pediatric patients was higher for those with stage 1, 2, or 3 disease (absolute difference of pediatric vs adult patients: stage 1, 18% [95% CI, 9.7%-26.3%]; stage 2, 36% [95% CI, 25.3%-46.7%]; stage 3, 39% [95% CI, 26.8%-51.2%]; and stage 4, 2% [95% CI, -8.2% to 12.2%]). Conclusions and Relevance: Although pediatric patients with head and neck melanoma present with similar tumor depth and more frequent nodal metastases than do adult patients, younger patients have higher overall survival.

Catch-up growth in infants with laryngomalacia after supraglottoplasty.

IMPORTANCE: Laryngomalacia, the most common congenital anomaly of the infant airway, can lead to poor feeding and failure to thrive. The decision to perform the standard surgical treatment, supraglottoplasty, is often based upon a sustained period of poor weight gain or weight loss. OBJECTIVE: To characterize patterns of growth in infants with laryngomalacia, preceding and following supraglottoplasty. DESIGN: Retrospective chart review. Bioinformatics techniques were used to procure data from a clinical data warehouse based on the HL7 Reference Information Model consisting of all infants who underwent supraglottoplasty from June 1, 2005 to October 31, 2013. Height and weight measurements were obtained from 76 operated patients allowing for characterization of growth changes from the time of surgery to an average of 9 months following surgery. Logistic regression analysis was performed to examine the following variables for correlations with changes in weight, height and body mass index percentiles: patient age at surgery, preoperative weight, gender, and ethnic background. SETTING: Academic pediatric tertiary medical center. PARTICIPANTS: Patients under 2 years of age at the time of surgery, who underwent supraglottoplasty for laryngomalacia, with height and weight measurements recorded within 3 months preceding surgery and greater than 3 months following surgery. INTERVENTION: Supraglottoplasty. MAIN OUTCOMES AND MEASURES: Change in weight, height and body mass index (BMI) percentile from pre-op to post-op. RESULTS: BMI increased from a mean of 15.4 to 18.0 and BMI percentile from a mean of 34 to 51 from pre-op to post-op. The largest BMI percentile increases were observed in infants that were 3 months or younger at the time of surgery, as well as in those under 12 months of age, who were in the lowest BMI quintile. CONCLUSIONS AND RELEVANCE: Infants who underwent supraglottoplasty tended to be small in weight and stature, and gained weight after surgery. Most of the weight gain occurred within 6 months of surgery. The largest increases in BMI percentile were observed in infants who were younger and smaller at the time of surgery while the infants older than 18 months had no significant gain.

Analysis of Growth Curves in Children After Adenotonsillectomy.

IMPORTANCE: Several studies have documented that children gain more weight than expected after adenotonsillectomy. OBJECTIVES: To examine patterns of change in weight and stature percentiles in children after adenotonsillectomy and to analyze clinical and demographic correlates of shifts in the growth curve. DESIGN, SETTING, AND PARTICIPANTS: In this retrospective medical record review, we studied patients 18 years and younger who underwent adenotonsillectomy at an academic pediatric tertiary medical center and had at least one height and weight measurement recorded at each of the following time points: within 3 months before surgery, within 3 to 9 months after surgery, and within 12 to 27 months after surgery. Data were procured from all children from January 1, 2007, through October 31, 2012, and initially included 2893 surgical patients and 161,458 height and weight measurements. The final database consisted of 815 patients with adequate growth data and multiple time points. Logistic regression analysis was performed to examine patient age at surgery, preoperative weight, sex, and ethnic background for correlations with changes in weight, height, and body mass index percentiles. MAIN OUTCOMES AND MEASURES: Change in weight, height, and body mass index percentile before and after surgery. RESULTS: At 18 months after surgery, weight percentiles in the study group increased by a mean of 6.3 percentile points (P < .001). Body mass index percentiles increased by a mean of 8.0 percentile points (P < .001). The greatest increases in weight percentiles were observed in children who were between the 1st and 60th percentiles for weight (P < .001) and younger than 4 years at the time of surgery (P < .001). An increase in weight percentile was not observed in children who preoperatively were already above the 80th percentile in weight (P = .15). CONCLUSIONS AND RELEVANCE: Weight gain after adenotonsillectomy occurs primarily in patients who are smaller and younger at the time of surgery and does not correlate with increased rates of obesity.

High prevalence of hearing impairment in HIV-infected Peruvian children.

OBJECTIVES: To measure the prevalence and to identify risk factors of hearing impairment in human immunodeficiency virus-infected children living in Peru. STUDY DESIGN: Cross-sectional observational study. SETTING: Two public hospitals and 1 nonprofit center in Lima, Peru, between August 2009 and April 2010. SUBJECTS: A total of 139 HIV-infected children, ages 4 to 19 years. METHODS: Hearing impairment and otologic health were assessed with pure tone audiometry, tympanometry, and otoscopy. The primary outcome was hearing loss, defined as average threshold >25dB for 0.5, 1, 2, and 4 kHz, in one or both ears. Historical and socioeconomic information was obtained through parental survey and medical chart review. Statistical analysis included univariate analysis and multivariate logistic regression. RESULTS: Fifty-four (38.8%) of 139 children had hearing impairment. On multivariate analysis, risk factors included: tympanic membrane perforation (odds ratio [OR] 7.08; 95% confidence interval [CI], 1.65-30.5; P = .01), abnormal tympanometry (OR 2.71; 95% CI, 1.09-6.75; P = .03), cerebral infection (OR 11.6; 95% CI, 1.06-126; P = .05), seizures (OR 5.20; 95% CI, 1.21-22.4; P = .03), and CD4 cell count <500 cells/mm(3) (OR 3.53; 95% CI, 1.18-10.5; P = .02). CONCLUSIONS: The prevalence of hearing impairment in HIV-infected children in Lima, Peru was 38.8%. Middle ear disease, prior cerebral infection, and low CD4 cell count were significantly associated with hearing impairment. The high prevalence of hearing impairment emphasizes the need for periodic hearing assessment in the routine clinical care of HIV-infected children.

Synthesis and evaluation of substrate analogue inhibitors of trypanothione reductase.

Trypanothione reductase (TR) is found in the trypanosomatid parasites, where it catalyses the NADPH-dependent reduction of the glutathione analogue, trypanothione, and is a key player in the parasite's defenses against oxidative stress. TR is a promising target for the development of antitrypanosomal drugs; here, we report our synthesis and evaluation of compounds 3-5 as low micromolar Trypanosoma cruzi TR inhibitors. Although 4 and 5 were designed as potential irreversible inhibitors, these compounds, as well as 3, displayed reversible competitive inhibition. Compound 3 proved to be the most potent inhibitor, with a K(i) = 2 µM.

Prevalence and risk factors for encephalomyocarditis virus infection in Peru.

Although encephalomyocarditis virus (EMCV) infection has been commonly documented among domestic animals, less is known about EMCV transmission among humans. Recently, we described the isolation of EMCV from two febrile patients in Peru. To further investigate EMCV transmission in Peru, we screened febrile patients reporting to health clinics in Peru for serological evidence of recent EMCV infection. We also conducted a serological survey for EMCV-neutralizing antibodies in the city of Iquitos, located in the Amazon basin department of Loreto, Peru. Additionally, we screened serum from rodents collected from 10 departments in Peru for evidence of EMCV exposure. EMCV infection was found to be only rarely associated with acute febrile disease in Peru, accounting for <1% of febrile episodes analyzed. Despite the low acute disease burden associated with the virus, human exposure was quite common, as prevalence of EMCV-neutralizing antibodies ranged between 6.0% in the coastal city of Tumbes and >17% in cities in the tropical rainforest of northeastern Peru (Iquitos and Yurimaguas). On the basis of the serological survey conducted in Iquitos, risk factors for past infection include increased age, socioeconomic indicators such as residence construction materials and neighborhood, and swine ownership. Evidence from the rodent survey indicates that EMCV exposure is common among Murinae subfamily rodents in Peru (9.4% EMCV IgG positive), but less common among Sigmodontinae rodents (1.0% positive). Further studies are necessary to more precisely delineate the mode of EMCV transmission to humans, other potential disease manifestations, and the economic impact of EMCV transmission among swine in Peru.

Hearing impairment and poverty: the epidemiology of ear disease in Peruvian schoolchildren.

OBJECTIVES: 1) To measure prevalence of hearing impairment (HI) in schoolchildren living in poverty in Peru. 2) To identify risk factors for HI and assess its impact on academic performance. STUDY DESIGN: Cross-sectional. SETTING: Elementary schools in an asentimiento humano (shantytown) near Lima, Peru, October 2008 to March 2009. SUBJECTS: Schoolchildren (n = 335), ages six to 19 years. METHODS: Audiological health was assessed with pure-tone audiometry, tympanometry, and otoscopy. The primary outcome was HI, defined as average threshold >25 dB HL for 0.5, 1, 2, and 4 kHz, in one or both ears (per World Health Organization/International Organization for Standardization). A questionnaire on health history was administered to parents. Statistical analysis included univariate analysis for chi(2) values and odds ratios (ORs), and multivariate logistic regression. RESULTS: HI prevalence: 6.9 percent (95% confidence interval [CI] 4.2%-9.6%). Risk factors for HI (OR, 95% CI, P value): neonatal jaundice (5.59, 1.63-19.2, 0.015), seizure (7.31, 2.50-21.4, 0.0013), hospitalization (4.01, 1.66-9.68, 0.003), recurrent otitis media (5.06, 1.98-12.9, 0.002), past otorrhea (4.70, 1.84-12.0, 0.003), family history of HI at <35 years (2.91, 1.19-7.14, 0.026), tympanic membrane abnormality (13.8, 4.48-42.7, <0.001), cerumen impaction (15.8, 4.71-53.1, <0.001), and eustachian tube dysfunction (4.87, 1.74-13.7, <0.001). HI was an independent predictor of academic failure (3.36, 1.15-9.82, 0.03). CONCLUSIONS: Impoverished Peruvian schoolchildren were four to seven times more likely to experience HI than children living in higher-income countries. Untreated middle ear disease in the context of limited access to pediatric care was a major risk factor for HI. Furthermore, HI was associated with worse scholastic achievement. These results support prioritization of pediatric ear health as an essential component of the global health agenda, especially in resource-poor countries.

The anti-apoptotic activity of BAG3 is restricted by caspases and the proteasome.

BACKGROUND: Caspase-mediated cleavage and proteasomal degradation of ubiquitinated proteins are two independent mechanisms for the regulation of protein stability and cellular function. We previously reported BAG3 overexpression protected ubiquitinated clients, such as AKT, from proteasomal degradation and conferred cytoprotection against heat shock. We hypothesized that the BAG3 protein is regulated by proteolysis. METHODOLOGY/PRINCIPAL FINDINGS: Staurosporine (STS) was used as a tool to test for caspase involvement in BAG3 degradation. MDA435 and HeLa human cancer cell lines exposed to STS underwent apoptosis with a concomitant time and dose-dependent loss of BAG3, suggesting the survival role of BAG3 was subject to STS regulation. zVAD-fmk or caspase 3 and 9 inhibitors provided a strong but incomplete protection of both cells and BAG3 protein. Two putative caspase cleavage sites were tested: KEVD (BAG3(E345A/D347A)) within the proline-rich center of BAG3 (PXXP) and the C-terminal LEAD site (BAG3(E516A/D518A)). PXXP deletion mutant and BAG3(E345A/D347A), or BAG3(E516A/D518A) respectively slowed or stalled STS-mediated BAG3 loss. BAG3, ubiquitinated under basal growth conditions, underwent augmented ubiquitination upon STS treatment, while there was no increase in ubiquitination of the BAG3(E516A/D518A) caspase-resistant mutant. Caspase and proteasome inhibition resulted in partial and independent protection of BAG3 whereas inhibitors of both blocked BAG3 degradation. STS-induced apoptosis was increased when BAG3 was silenced, and retention of BAG3 was associated with cytoprotection. CONCLUSIONS/SIGNIFICANCE: BAG3 is tightly controlled by selective degradation during STS exposure. Loss of BAG3 under STS injury required sequential caspase cleavage followed by polyubiquitination and proteasomal degradation. The need for dual regulation of BAG3 in apoptosis suggests a key role for BAG3 in cancer cell resistance to apoptosis.

The synthesis and inhibitory activity of dethiotrypanothione and analogues against trypanothione reductase.

Trypanothione reductase (TR) catalyzes the NADPH-dependent reduction of trypanothione disulfide (1). TR plays a central role in the trypanosomatid parasite's defense against oxidative stress and has emerged as a promising target for antitrypanosomal drugs. We describe the synthesis and activity of dethiotrypanothione and analogues (2-4) as inhibitors of Trypanosoma cruzi TR. The syntheses of these macrocycles feature ring-closing olefin metathesis (RCM) reactions catalyzed by ruthenium catalyst 17. Derivative 4 is our most potent inhibitor with a Ki=16 microM.

SELDI-TOF mass spectrometry for cancer biomarker discovery and serum proteomic diagnostics.

Proteomics is more than the identification of proteins that are altered in expression as a consequence of disease. Among the tools critical for the detection, treatment and monitoring of disease are biomarkers. The necessity for new methods to identify and validate biomarkers is underscored by the increased survival of patients diagnosed at early stages of cancer. Serum proteomic pattern diagnostics is a new technique in which proteomic signatures are used as a diagnostic classifier. Surface-enhanced laser desorption/ionization time-of-flight mass spectrometry has shown promise as a modality for biomarker discovery of early-stage cancers. Mass spectrometry-derived protein signatures have been modeled and are now moving into validation. Further sequencing of these key features can lead to new insights into disease etiology and intervention.

The role of proteomics in the diagnosis and treatment of ovarian cancer.

Ovarian cancer is the leading cause of gynecologic cancer death in the Western world and more than 70% of patients are diagnosed with advanced stage disease. The high mortality rate is due to the difficulty in the early detection of ovarian cancer. Current screening strategies lack the necessary sensitivity and specificity to reliably and accurately diagnose affected women, prompting investigators to seek alternative means of analysis found in protein pathways and networks. Proteomics seeks to advance the understanding of how proteins interact in cancer and may provide a mechanism for early stage diagnosis. The proteomic techniques of laser capture microdissection, mass spectrometry and tissue lysate arrays have led to the discovery of new biomarkers and the identification, development and approval of a number of targeted therapeutic agents. Following validation through clinical trials, the application of these techniques will contribute to the changing paradigm of cancer detection and treatment toward personalized medicine.