Predicting NOx Catalysis by Quantifying Ce3+ from Surface and Lattice Oxygen.

Our work introduces a novel technique based on the magnetic response of Ce3+ and molecular oxygen adsorbed on the surface of nanoceria and ceria-based catalysts that quantifies the number and type of defects and demonstrates that this information is the missing link that finally enables predictive design of NOx catalysis in ceria-based systems. The new insights into ceria catalysis are enabled by quantifying the above for different ceria nanoparticle shapes (i.e., surface terminations) and O2 partial pressure. We used ceria nanorods, cubes, and spheres and evaluated them for catalytic reduction of NO by CO. We then demonstrated the quantitative prediction of the reactivity of nanomaterials via their magnetism in different atmospheric environments. We find that the observed enhancement of reactivity for ceria nanocubes and nanorods is not directly due to improved reactivity on those surface terminations but rather due to the increased ease of generating lattice defects in these materials. Finally, we demonstrate that the method is equally applicable to highly topical and industrially relevant ceria mixed oxides, using nanoscale alumina-supported ceria as a representative case-a most ill-defined catalyst. Because the total oxide surface is a mixture of active ceria and inactive support and ceria is not likely present as crystallographically well-defined phases, reactivity does not easily scale with surface area or a surface termination. The key parameter to design efficient NO reduction in ceria-based catalysts is knowing and controlling the surface localized excess Ce3+ ion areal density.

Pediatric Neurosurgery Patients Need More than a Pediatric Neurosurgeon. Part II. A Clinical Report: In the USA Lack of Parent/Caregiver Compliance Interferes with the Patient Care Sequence.

We have previously reported on the initiation, development, and preliminary results of a comprehensive multidisciplinary team for the long-term management of children with neurosurgical conditions other than spina bifida. This report addresses the follow-up of the care of these patients and identifies limitations in the care sequence including, but not limited to, lack of parental/caregiver compliance, unmet educational needs, and medical insurance issues.

Characteristics and In-Hospital Outcomes of Peripartum Cardiomyopathy Diagnosed During Delivery in the United States From the Nationwide Inpatient Sample (NIS) Database.

BACKGROUND: Peripartum cardiomyopathy (PPCM) is associated with advanced maternal age, African-American race, hypertensive disorders of pregnancy, and multiple-gestation pregnancies. Less is known regarding racial differences in risk factors and predictors of adverse in-hospital outcomes. METHODS AND RESULTS: A total of 1,337 women with PPCM were identified with the use of the Nationwide Inpatient Sample (2004-2011). Clinical profiles and maternal outcomes in delivering mothers with and without PPCM were compared and stratified by race. In multivariate analysis, established risk factors for PPCM were confirmed. Anemia (odds ratio [OR] 2.0, 95% confidence interval [CI] 1.6-2.5; P < .0001), asthma (OR 2.2, 95% CI 1.5-3.2; P = .0002), smoking (OR 33.6, 95% CI 9.3-159.4; P < .0001), and thyroid disease (OR 5.9; 95% CI 1.5-21.3; P = .01) were associated with PPCM. Risk factors significant in whites, African Americans, and Hispanics were hypertension during pregnancy and anemia. Patients with PPCM had higher rates of in-hospital adverse outcomes (P < .0001), but no differences in race or comorbidities predicted adverse events. CONCLUSIONS: Hypertensive disorders during pregnancy and anemia were associated with PPCM in whites, African Americans, and Hispanics, providing further evidence that vascular stress may play a role in the pathogenesis of PPCM. Thyroid disorders may represent a novel risk factor for PPCM.

Association of Geroprotective Effects of Metformin and Risk of Open-Angle Glaucoma in Persons With Diabetes Mellitus.

IMPORTANCE: Caloric restriction mimetic drugs have geroprotective effects that delay or reduce risks for a variety of age-associated systemic diseases, suggesting that such drugs might also have the potential to reduce risks of blinding ophthalmologic conditions for which age is a major risk factor. OBJECTIVE: To determine whether the caloric restriction mimetic drug metformin hydrochloride is associated with reduced risk of open-angle glaucoma (OAG) in persons with diabetes mellitus. DESIGN, SETTING, AND PATIENTS: Retrospective cohort study of patients aged 40 years or older with diabetes mellitus and no preexisting record of OAG in a large US managed care network from January 1, 2001, through December 31, 2010. EXPOSURES: Quantity of metformin and other prescribed diabetes medications as captured from outpatient pharmacy records. MAIN OUTCOMES AND MEASURES: Risk of developing OAG. RESULTS: Of 150 016 patients with diabetes mellitus, 5893 (3.9%) developed OAG. After adjusting for confounding factors, those prescribed the highest quartile of metformin hydrochloride (>1110 g in 2 years) had a 25% reduced OAG risk relative to those who took no metformin (hazard ratio = 0.75; 95% CI, 0.59-0.95; P = .02). Every 1-g increase in metformin hydrochloride use was associated with a 0.16% reduction in OAG risk (adjusted hazard ratio = 0.99984; 95% CI, 0.99969-0.99999; P = .04), which predicts that taking a standard dose of 2 g of metformin hydrochloride per day for 2 years would result in a 20.8% reduction in risk of OAG. After accounting for potential confounders, including metformin and diabetic medications, the risk of developing OAG was increased by 8% (hazard ratio = 1.08; 95% CI, 1.03-1.13; P = .003) for each unit of increase in glycated hemoglobin level. CONCLUSIONS AND RELEVANCE: Metformin use is associated with reduction in risk of developing OAG, and risk is reduced even when accounting for glycemic control in the form of glycated hemoglobin level. Other diabetes medications did not confer a similar OAG risk reduction. This study suggests that metformin may be affecting OAG risk on multiple levels, some involving improved glycemic control and some involving mechanisms outside glycemic control such as neurogenesis, inflammatory systems, or longevity pathways targeted by caloric restriction mimetic drugs. If confirmed by prospective clinical trials, these findings could lead to novel treatments for this sight-threatening disease.

Structural evolution of an intermetallic Pd-Zn catalyst selective for propane dehydrogenation.

We report the structural evolution of Pd-Zn alloys in a 3.6% Pd-12% Zn/Al2O3 catalyst which is selective for propane dehydrogenation. High signal-to-noise, in situ synchrotron X-ray diffraction (XRD) was used quantitatively, in addition to in situ diffuse-reflectance infrared Fourier transform spectroscopy (DRIFTS) and extended X-ray absorption fine structure (EXAFS) to follow the structural changes in the catalyst as a function of reduction temperature. XRD in conjunction with DRIFTS of adsorbed CO indicated that the ß1-PdZn intermetallic alloy structure formed at reduction temperatures as low as 230 °C, likely first at the surface, but did not form extensively throughout the bulk until 500 °C which was supported by in situ EXAFS. DRIFTS results suggested there was little change in the surfaces of the nanoparticles above 325 °C. The intermetallic alloy which formed was Pd-rich at all temperatures but became less Pd-rich with increasing reduction temperature as more Zn incorporated into the structure. In addition to the ß1-PdZn alloy, a solid solution phase with face-center cubic structure (α-PdZn) was present in the catalyst, also becoming more Zn-rich with increasing reduction temperature.

Risk factors for developing thyroid-associated ophthalmopathy among individuals with Graves disease.

IMPORTANCE: Thyroid-associated ophthalmopathy (TAO) is a common and debilitating manifestation of Graves disease (GD). Presently little is known about factors that may increase the risk of developing TAO among patients with GD. OBJECTIVE: To identify risk factors associated with the development of TAO among individuals with newly diagnosed GD. DESIGN, SETTING, AND PARTICIPANTS: In this longitudinal cohort study, all beneficiaries 18 years of age or older with newly diagnosed GD who were continuously enrolled in a large nationwide US managed care network and who visited an eye care professional 1 or more times from 2001 to 2009 were identified. International Classification of Diseases, Ninth Revision, Clinical Modification billing codes were used to identify those who developed manifestations of TAO. Multivariable Cox regression was used to determine the hazard of developing TAO among persons with newly diagnosed GD, with adjustment for sociodemographic factors, systemic medical conditions, thyrotropin levels, and medical and surgical interventions for management of hyperthyroidism. MAIN OUTCOMES AND MEASURES: Manifestations of TAO measured by hazard ratios (HRs) with 95% CIs. RESULTS: Of 8404 patients with GD who met the inclusion criteria, 740 (8.8%) developed TAO (mean follow-up, 374 days since initial GD diagnosis). After adjustment for potential confounders, surgical thyroidectomy, alone or in combination with medical therapy, was associated with a 74% decreased hazard for TAO (adjusted HR, 0.26 [95% CI, 0.12-0.51]) compared with radioactive iodine therapy alone. Statin use (for ≥60 days in the past year vs <60 days or nonuse) was associated with a 40% decreased hazard (adjusted HR, 0.60 [CI, 0.37-0.93]). No significant association was found for the use of nonstatin cholesterol-lowering medications or cyclooxygenase 2 inhibitors and the development of TAO. CONCLUSIONS AND RELEVANCE: If prospective studies can confirm our finding that a thyroidectomy and statin use are associated with substantially reduced hazards for TAO among patients with GD, preventive measures for this burdensome manifestation of GD may become a reality.

Reliable exclusion of acute coronary syndrome among hospitalized patients with elevated troponin.

BACKGROUND: Elevated cardiac troponin I (cTnI) occurs in acute coronary syndrome (ACS) as well as various scenarios not associated with ACS. HYPOTHESIS: Simple clinical criteria can reliably exclude ACS among hospitalized patients with elevated cTnI. METHODS: Records for patients hospitalized from January to April 2011 with elevated cTnI (>0.29 ng/dL) and an available echocardiogram were retrospectively reviewed. Patients with ST-segment elevation myocardial infarction were excluded. Based on available clinical data, patients were classified as having ACS or elevation of cTnI unrelated to ACS (non-ACS). Median follow-up was 365 days. RESULTS: Of 265 records meeting inclusion criteria, 82 (31%) had ACS and 183 (69%) had non-ACS. In multivariable analysis, odds ratios for non-ACS were 7.6 (95% confidence interval [CI]: 3.8-15.3) for peak cTnI <2 ng/dL, 6.3 (95% CI: 3.1-13.0) for absent wall-motion abnormality, and 4.4 (95% CI: 2.2-8.6) for no prior coronary artery disease history. The area under the receiver operating curve for amodel using these 3 variables was 0.86, with a 98% negative predictive value for excluding ACS. Patients who met these 3 criteria had no ACS-related deaths over 1-year follow-up. CONCLUSIONS: Hospitalized patients with peak Tn level<2 ng/dL, no prior history of coronary artery disease, and no new echocardiographic wall-motion abnormality appear to have a very low likelihood of ACS. Prospective validation of these results is needed to determine whether additional diagnostic testing could be safely avoided in hospitalized patients meeting these simple clinical criteria.

Congenital scoliosis SRS-22 outcomes in children treated with observation, surgery, and VEPTR.

STUDY DESIGN: Prospective, nonrandomized study of children with congenital scoliosis. OBJECTIVE: To determine the outcomes of children with congenital scoliosis using SRS-22. SUMMARY OF BACKGROUND DATA: Outcome measures in children with congenital scoliosis are unreported. Novel treatments such as VEPTR (vertical expandable prosthetic titanium rib) must show positive patient-reported outcomes during treatment because improvement in pulmonary function has not been demonstrated. METHODS: Patients with congenital scoliosis were prospectively enrolled and divided into 3 groups: children under observation (OBSERVATION), children who had surgery (SURGICAL), and children treated with VEPTR (VEPTR). The SRS-22 questionnaire reports 6 domains: Total, Function, Mental Health, Image, Satisfaction, and Pain. SRS-22 questionnaires were prospectively collected from 184 OBSERVATION patients, 27 SURGICAL patients, and 22 VEPTR patients. Because of repeated measurement on each patient, the observations cannot be assumed to be independent. To account for this dependence, linear mixed models were used. RESULTS: OBSERVATION scores were near normal in all domains. Initial postoperative scores for Function and Pain decreased for the SURGICAL group and subsequently Total, Function, Image, and Satisfaction scores increased. Initial postoperative VEPTR scores in Mental Health and Pain decreased and Total, Function, and Image scores increased during subsequent visits. CONCLUSION: Children with congenital scoliosis had SRS-22 scores that compare favorably with scores reported in the literature for adolescent idiopathic scoliosis. For SURGICAL and VEPTR patients with congenital scoliosis, SRS-22 Total, Function, and Image scores increased over time. Function, Image, and Pain require focus in children with congenital scoliosis. This is the first study that documents improvement in outcomes of VEPTR patients while in treatment. LEVEL OF EVIDENCE: 2.

Maternal physiologic parameters in relationship to systemic inflammatory response syndrome criteria: a systematic review and meta-analysis.

OBJECTIVE: To establish the normal maternal range in healthy pregnant women for each component of the systemic inflammatory response syndrome (SIRS) criteria and compare these ranges with existing SIRS criteria. DATA SOURCES: PubMed, Embase, and ClinicalTrials.gov databases were searched to identify studies of healthy parturients from the first trimester through 12 weeks postpartum that reported maternal temperature, respiratory rate, PaCO2, heart rate, white blood cell count data, or a combination of these. METHODS OF STUDY SELECTION: Data were extracted from studies providing maternal values for components of SIRS criteria. The mean, standard deviation, and two standard deviations from the mean for all criteria parameters published in the literature were reported. TABULATION, INTEGRATION, AND RESULTS: Eighty-seven studies met inclusion criteria and included 8,834 patients and 15,237 data points: temperature (10 studies and 2,367 patients), respiratory rate (nine studies and 312 patients), PaCO2 (12 studies and 441 patients), heart rate (39 studies and 1,374 patients), and white blood cell count (23 studies and 4,553 patients). Overlap with SIRS criteria occurred in healthy pregnant women during the second trimester, third trimester, and labor for each of the SIRS criteria except temperature. Every mean value for PaCO2 during pregnancy (and up to 48 hours postpartum) was below 32 mm Hg. Two standard deviations above the mean for temperature, respiratory rate, and heart rate were 38.1°C, 25 breaths per minute, and 107 beats per minute, respectively. CONCLUSION: Current SIRS criteria often overlap with normal physiologic parameters during pregnancy and the immediate postpartum period; thus, alternative criteria must be developed to diagnose maternal sepsis.

The impact of Michigan's text messaging restriction on motor vehicle crashes.

PURPOSE: The purpose of this study was to determine the effects of Michigan's universal text messaging restriction (effective July 2010) across different age groups of drivers and crash severities. METHODS: Changes in monthly crash rates and crash trends per 10,000 licensed drivers aged 16, 17, 18, 19, 20-24, and 25-50 years were estimated using time series analysis for three levels of crash severity: (1) fatal/disabling injury; (2) nondisabling injury; and (3) possible injury/property damage only (PDO) crashes for the period 2005-2012. Analyses were adjusted for crash rates of drivers' aged 65-99 years, Michigan's unemployment rate, and gasoline prices. RESULTS: After the introduction of the texting restriction, significant increases were observed in crash rates and monthly trends in fatal/disabling injury crashes and nondisabling injury crashes, and significant decreases in possible injury/PDO crashes. The magnitude of the effects where significant changes were observed was small. CONCLUSIONS: The introduction of the texting restriction was not associated with a reduction in crash rates or trends in severe crash types. On the contrary, small increases in the most severe crash types (fatal/disabling and nondisabling injury) and small decreases in the least severe crash types (possible injury/PDO) were observed. These findings extend the literature on the effects of cell phone restrictions by examining the effects of the restriction on newly licensed adolescent drivers and adult drivers separately by crash severity.

Postoperative spine and VEPTR infections in children: a case-control study.

BACKGROUND: Surgical site infection (SSI) after pediatric scoliosis surgery is a major cause of morbidity. We compared the odds ratios of various potential risk factors for infection among patients who developed a deep SSI following spinal deformity surgery and those who remained infection free. METHODS: This was a case-control study, not a matched study. More noninfection cases (50) than infection cases (20) were selected because more were available. Twenty children with a deep SSI after scoliosis surgery were compared with 50 similar children who did not develop a deep SSI. Fourteen perioperative factors were examined in both the groups. RESULTS: Of the 20 patients who had a deep SSI, 14 had neuromuscular scoliosis. In the infected group, 6 patients had undergone vertical expandable prosthetic titanium rib placement, 2 had undergone growing rod insertion, and 12 had undergone posterior spinal fusion. Eighteen patients developed a SSI within 1 year of the operation and 2 patients presented with a SSI >1 year after surgery. Sixteen patients had positive cultures. Majority were skin flora: coagulase-negative Staphylococcus (8) and Propionibacterium acnes (4). Both patients with tracheostomies had Enterococcus faecalis infections. When comparing the 20 patients with deep SSI to the 50 controls, increased preoperative Cobb angle (P=0.011), increased postoperative Cobb angle (P=0.0043), nonambulatory status (P=0.0002), and increased length of stay (P=0.015) were associated with significantly increased odds of infection. CONCLUSIONS: Our study shows that patients with neuromuscular scoliosis are at higher risk of developing a deep SSI after spinal deformity surgery. Skin flora is a common cause of deep SSI. We have now instituted a standard skin preparation protocol to include alcohol and chlorhexidine washes the night before and the morning of surgery. We have altered our prophylactic antibiotic regimen to cover skin flora in all patients and gastrointestinal flora in patients with a tracheostomy. We have counseled the families of nonambulatory children with large neuromuscular curves regarding the significantly increased odds of postoperative deep SSI. LEVEL OF EVIDENCE: Level III.

Pediatric neurosurgery patients need more than a neurological surgeon: a clinical experience.

The Division of Pediatric Neurosurgery of the University of Florida College of Medicine Jacksonville initiated and developed a multidisciplinary comprehensive team for the management of patients with a neurosurgical condition other than spina bifida. This report relates the rationale and stages of development of a multidisciplinary team to facilitate the health care and special needs of these children.

Analysis of temporal variation in human masticatory cycles during gum chewing.

OBJECTIVE: The study investigated modulation of fast and slow opening (FO, SO) and closing (FC, SC) chewing cycle phases using gum-chewing sequences in humans. DESIGN: Twenty-two healthy adult subjects participated by chewing gum for at least 20s on the right side and at least 20s on the left side while jaw movements were tracked with a 3D motion analysis system. Jaw movement data were digitized, and chewing cycle phases were identified and analysed for all chewing cycles in a complete sequence. RESULTS: All four chewing cycle phase durations were more variant than total cycle durations, a result found in other non-human primates. Significant negative correlations existed between the opening phases, SO and FO, and between the closing phases, SC and FC; however, there was less consistency in terms of which phases were negatively correlated both between subjects, and between chewing sides within subjects, compared with results reported in other species. CONCLUSIONS: The coordination of intra-cycle phases appears to be flexible and to follow complex rules during gum-chewing in humans. Alternatively, the observed intra-cycle phase relationships could simply reflect: (1) variation in jaw kinematics due to variation in how gum was handled by the tongue on a chew-by-chew basis in our experimental design or (2) by variation due to data sampling noise and/or how phases were defined and identified.

Gauging interest of the general public in laser-assisted in situ keratomileusis eye surgery.

PURPOSE: To assess interest among members of the general public in laser-assisted in situ keratomileusis (LASIK) surgery and how levels of interest in this procedure have changed over time in the United States and other countries. METHODS: Using the Google Trends Web site, we determined the weekly frequency of queries involving the term "LASIK" from January 1, 2007, through January 1, 2011, in the United States, United Kingdom, Canada, and India. We fit separate regression models for each of the countries to assess whether residents of these countries differed in their querying rates on specific dates and over time. Similar analyses were performed to compare 4 US states. Additional regression models compared general public interest in LASIK surgery before and after the release of a 2008 Food and Drug Administration report describing complaints associated with this procedure. RESULTS: During 2007 to 2011, the Google query rate for "LASIK" was highest among persons residing in India, followed by the United Kingdom, Canada, and the United States. During this time period, the query rate declined by 40% in the United States, 24% in India, and 22% in the United Kingdom, and it increased by 8% in Canada. In all 4 of the US states examined, the query rate declined-by 52% in Florida, 56% in New York, 54% in Texas, and 42% in California. Interest in LASIK declined further among US citizens after the Food and Drug Administration report release. CONCLUSIONS: Interest among the general public in LASIK surgery has been waning in recent years.

Neurodevelopmental outcomes of premature infants with severe respiratory failure enrolled in a randomized controlled trial of inhaled nitric oxide.

OBJECTIVES: We hypothesized that inhaled nitric oxide (iNO) would not decrease death or neurodevelopmental impairment (NDI) in infants enrolled in the National Institute of Child Health and Human Development Preemie iNO Trial (PiNO) trial, nor improve neurodevelopmental outcomes in the follow-up group. STUDY DESIGN: Infants <34 weeks of age, weighing <1500 g, with severe respiratory failure were enrolled in the multicenter, randomized, controlled trial. NDI at 18 to 22 months corrected age was defined as: moderate to severe cerebral palsy (CP; Mental Developmental Index or Psychomotor score Developmental Index <70), blindness, or deafness. RESULTS: Of 420 patients enrolled, 109 who received iNO (52%) and 98 who received placebo (47%) died. The follow-up rate in survivors was 90%. iNO did not reduce death or NDI (78% versus 73%; relative risk [RR], 1.07; 95% CI, 0.95-1.19), or NDI or Mental Developmental Index <70 in the follow-up group. Moderate-severe CP was slightly higher with iNO (RR, 2.41; 95% CI, 1.01-5.75), as was death or CP in infants weighing <1000 g (RR, 1.22; 95% CI, 1.05-1.43). CONCLUSIONS: In this extremely ill cohort, iNO did not reduce death or NDI or improve neurodevelopmental outcomes. Routine iNO use in premature infants should be limited to research settings until further data are available.