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1.
J Chem Phys ; 152(5): 054702, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32035457

RESUMO

Indium oxide has received attention as an exciting candidate for catalyzing the CO2 hydrogenation to methanol due to its high selectivity (>80%). Compared to the extent of research on the activity of indium oxide-based powder catalysts, very little is known about the phenomena associated with the formation of surface alloys involving indium or the growth mechanism for indium oxide nanoparticles. In this report, scanning tunneling microscopy and X-ray photoelectron spectroscopy (XPS) were employed to elucidate the growth mode, structure, and chemical state of In/Au(111) alloys and InOx/Au(111) inverse model catalysts. Our study reveals distinct morphological differences between In/Au(111) and InOx/Au(111), and the InOx structure also depends strongly on the preparation conditions. In/Au surface alloy systems with extremely low coverage (0.02 ML) form islands preferentially on the elbow sites of reconstructed Au(111) herringbone, regardless of hexagonally closed packed and face centered cubic stacking. At higher coverage (0.1 ML), the In islands expand over the herringbone in the ⟨110⟩ direction and create two dimensional domain structures over the entire surfaces. Moreover, this 2D domain structure is disturbed by temperature with high dispersion of indium atoms observed during the annealing process. Oxidation of the In/Au(111) surface alloys with O2 at 550 K produces InOx/Au(111) systems which contain various sizes of InOx aggregates (from 0.7 nm to 10 nm). On the other hand, InOx/Au(111) surfaces prepared by vapor deposition of In at 550 K in an O2 background exhibit highly dispersed and uniformly small InOx particles (∼1 nm). Both InOx systems were confirmed to be partially oxidized by XPS.

2.
Pediatr Pulmonol ; 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31951679

RESUMO

OBJECTIVES: Although the benefits of albuterol delivered via metered-dose inhalers with a spacer (MDI+S) have been increasingly recognized, the evidence regarding the cost-effectiveness of MDI+S compared to nebulization (NEB) is not sufficient, especially in less-affluent countries, where the clinical and economic burden of the disease is the greatest. The aim of the present study was to evaluate the cost-effectiveness of MDI+S vs NEB for delivering albuterol for the treatment of pediatric asthma exacerbations. METHODS: A decision-analysis model was developed to estimate the cost-effectiveness of MDI+S vs NEB for delivering albuterol for the treatment of pediatric asthma exacerbations. Effectiveness parameters were obtained from a systematic review of the literature. Cost data were obtained from hospital bills and from the national manual of drug prices in Colombia. The study was carried out from the perspective of the national healthcare system in Colombia, a middle-income country (MIC). The main outcome of the model was the avoidance of hospital admission. RESULTS: For the base-case analysis, the model showed that compared to NEB, using MDI+S for the delivery of albuterol was associated with lower total costs (US$96.68 vs US$121.41 average cost per patient) and a higher probability of hospital admission avoided (0.9219 vs 0.8900), thus leading to dominance. CONCLUSIONS: This study shows that in Colombia, an MIC, compared with NEB, the use of MDI+S for delivering albuterol for the treatment of pediatric asthma exacerbations is the preferred strategy because it is associated with a lower probability of hospital admission at lower total treatment costs.

4.
Paediatr Drugs ; 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31939108

RESUMO

INTRODUCTION: The role of macrolides for treatment of children with acute asthma or wheezing exacerbations is unclear. OBJECTIVE: The aim of this systematic review was to evaluate the effectiveness of macrolides in children with recurrent wheezing presenting with acute asthma or wheezing exacerbation. METHODS: We conducted an electronic search in MEDLINE, EMBASE, CINAHL, LILACS, CENTRAL, and ClinicalTrials.gov. STUDY SELECTION CRITERIA: Randomized controlled trials of macrolides (any macrolide) compared with placebo or standard treatment in children up to 18 years with recurrent wheezing/asthma presenting with an acute exacerbation. OUTCOMES: Primary outcomes were need for hospitalization and/or time of acute asthma/wheezing symptoms resolution; secondary outcomes were duration of stay in the emergency department (ED)/clinic, severity of symptoms of the index episode, use of additional systemic corticosteroids or short active ß-2 agonists, changes in lung function measures, ED visit/hospitalization during first week after index episode, time to next exacerbation, or adverse effects (AEs). RESULTS: Only three studies met the inclusion criteria (n = 334 children, 410 treated episodes); two studies included recurrent wheezers and the third included asthmatic children. There was no difference in hospitalization between groups, but children treated with macrolides had a significantly lower time to symptoms resolution than controls, although the magnitude of benefit remains to be quantified due to no normal distribution data presented. There was no difference in time to next episode of exacerbation (HR 0.96; 95% CI 0.71-1.28; I2 = 0%; p = 0.77). In one study, children receiving macrolides had a significant decrease in the severity of symptoms, decrease use of salbutamol, and another study showed improved lung function. No study evaluated antibiotic resistance development. CONCLUSIONS: Limited evidence support that a macrolide trial could be considered in children with acute asthma or recurrent wheezing exacerbation.

5.
Am J Case Rep ; 21: e919724, 2020 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-31955178

RESUMO

BACKGROUND Histoplasmosis results from the inhalation of spores from the fungus, Histoplasma capsulatum. A case is presented of pulmonary histoplasmosis associated with altered mental state and hypercalcemia following allogeneic hematopoietic stem cell transplantation for acute myeloid leukemia (AML). CASE REPORT A 75-year-old man with a five-day history of AML treated with allogeneic hematopoietic stem cell transplantation, presented with weakness, fatigue, and slow mentation. Computed tomography (CT) of the brain was unremarkable. Laboratory investigations showed serum albumin of 2.9 g/dL, calcium of 11.6 mg/dL, ionized calcium of 1.55 mmol/L, parathyroid hormone (PTH) <6.3 pg/mL, and 25-hydroxy vitamin D of 14.4 ng/mL. Treatment began with intravenous cefepime 1 gm bid, normal saline, and the bisphosphonate, pamidronate, administered as a single dose. Three days later, his clinical status declined. He developed a dry productive cough, his oxygen saturation (O2 Sat) was 90%, and his mental status worsened. Chest CT showed diffuse bilateral lung infiltrates with ground glass opacities. Bronchioalveolar lavage and transbronchial biopsy were negative for Pneumocystis jiroveci pneumonia (PJP). The CMV rival load was 195 IU/mL. Urinalysis for Histoplasma antigen and the Fungitell® assay were positive. Treatment commenced with intravenous voriconazole (250 mg, bid) and ganciclovir (5 mg/kg, bid). A left lower lobe transbronchial lung biopsy was positive for Histoplasma capsulatum and negative for CMV. CONCLUSIONS This case report has highlighted the need for awareness of the diagnosis of histoplasmosis in patients with allogeneic hematopoietic stem cell transplantation who present with an altered mental state in the setting of hypercalcemia.

6.
Pediatrics ; 145(1)2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31843863

RESUMO

CONTEXT: Invasive pneumococcal disease (IPD) and pneumonia are a leading cause of morbidity and mortality throughout the world, and asthma is the most common chronic disease of childhood. OBJECTIVE: To evaluate the risk of IPD or pneumonia among children with asthma after the introduction of pneumococcal conjugate vaccines (PCVs). DATA SOURCES: Four electronic databases were searched. STUDY SELECTION: We selected all cohorts or case-control studies of IPD and pneumonia in populations who already received PCV (largely 7-valent pneumococcal conjugate vaccine), but not 23-valent pneumococcal polysaccharide, in which authors reported data for children with asthma and in which healthy controls were included, without language restriction. DATA EXTRACTION: Two reviewers independently reviewed all studies. Primary outcomes were occurrence of IPD and pneumonia. Secondary outcomes included mortality, hospital admissions, hospital length of stay, ICU admission, respiratory support, costs, and additional medication use. RESULTS: Five studies met inclusion criteria; of those, 3 retrospective cohorts (∼26 million person-years) and 1 case-control study (N = 3294 children) qualified for the meta-analysis. Children with asthma had 90% higher odds of IPD than healthy controls (odds ratio = 1.90; 95% confidence interval = 1.63-2.11; I2 = 1.7%). Pneumonia was also more frequent among children with asthma than among controls, and 1 study reported that pneumonia-associated costs increased by asthma severity. LIMITATIONS: None of the identified studies had information of asthma therapy or compliance. CONCLUSIONS: Despite PCV vaccination, children with asthma continue to have a higher risk of IPD than children without asthma. Further research is needed to assess the need for supplemental 23-valent pneumococcal polysaccharide vaccination in children with asthma, regardless of their use of oral steroids.

7.
J Investig Med ; 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31806672

RESUMO

Infants requiring hospitalization due to a viral lower respiratory tract infection (LRTI) have a high risk of developing recurrent respiratory illnesses in early life and asthma beyond childhood. Notably, all validated clinical scales for viral LRTI have focused on predicting acute severity instead of recurrence. We present a novel clinical approach combining individual risk factors with bedside clinical parameters to predict recurrence after viral LRTI hospitalization in young children. A retrospective longitudinal cohort of young children (≤3 years) designed to define clinical predictive factors of recurrent respiratory illnesses within 12 months after hospitalization due to PCR-confirmed viral LRTI. Data collection was through electronic medical record. We included 138 children hospitalized with viral LRTI. Using automatic stepwise logistic model selection, we found that the strongest predictors of recurrence in infants hospitalized for the first time were severe prematurity (≤32 weeks' gestational age, OR=5.19; 95% CI 1.76 to 15.32; p=0.002) and a clinical score that weighted hypoxemia, subcostal retractions and wheezing (OR=3.33; 95% CI 1.59 to 6.98; p<0.001). After the first hospitalization, the strongest predictors of subsequent episodes were wheezing (OR=5.62; 95% CI 1.03 to 30.62; p=0.04) and family history of asthma (OR=5.39; 95% CI 1.04 to 27.96; p=0.04). We found that integrating individual risk factors (eg, prematurity or family history of asthma) with bedside clinical assessment (eg, wheezing, subcostal retractions or hypoxemia) can predict the risk of recurrence after viral LRTI hospitalization in infants. This strategy may enable clinically oriented subsetting of infants with viral LRTI based on individual predictors for recurrent respiratory illnesses during early life.

8.
Case Rep Endocrinol ; 2019: 2502174, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31781416

RESUMO

Phaeochromocytomas and paragangliomas are rare catecholamine-secreting tumours arising from the adrenal medulla or sympathetic paraganglia. It is known that 20-30% of all cases occur as a result of germline variants in several well known genes. The TMEM127 gene was recently identified as a new phaeochromocytoma susceptibility gene. However, until a larger sample of cases is available, the prevalence, genotype-phenotype correlation, and a clear predominant biochemical pattern of TMEM127-related PCC, remain to be defined. We present a woman with the pathogenic variant c.86delG (p.Arg29Leufs∗52) in the TMEM127 gene, which has not been previously reported, associated to a bilateral phaeochromocytoma, with an uncommon initial clinical presentation and a biochemical profile that is distinctly adrenergic. Her two young children carry the same variant and are, at present, disease-free. Physicians should be aware that phaeochromocytoma can manifest in an atypical manner, as with episodic hypotension, mainly if the symptoms have no obvious aetiology and they worsen over time. This case also supports the presence of a predominant adrenaline secreting pattern in TMEM127-positive tumours, as well as the need to consider multigene panel testing in patients with bilateral phaeochromocytomas.

9.
AORN J ; 110(6): 596-604, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31774154

RESUMO

Perioperative and sterile processing department personnel commonly use visual inspection to validate surgical instrument cleanliness. This validation process does not detect microbes (eg, bacteria, viruses) and the resultant inadequately decontaminated instruments can put patients at risk for developing surgical site infections. Sterile processing department personnel should use a rapid, straightforward method to validate surgical instrument cleanliness objectively. During a quality improvement project at a military treatment facility, staff members found that adenosine triphosphate (ATP)-based technology was a viable and affordable solution for detecting bioburden and validating cleaning practices. The project design compared manually and mechanically cleaned cannulated instruments (59 of each) and identified 16 contaminated instruments, 14 of which had been manually cleaned. The contamination rate after mechanical cleaning was significantly lower (P = .0022) compared with manual cleaning. As a result of this quality improvement project, this facility fully implemented the technology to validate instrument cleaning.

10.
BMC Res Notes ; 12(1): 767, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31767032

RESUMO

OBJECTIVE: To advance public health support for the U.S. Department of Housing and Urban Development's smoke-free rule, the Centers for Disease Control and Prevention collaborated with the Georgia Institute of Technology to develop a geospatial mapping tool. The objective was to create a tool state and local public health agencies could use to tailor smoke-free educational materials and cessation interventions for specific public housing development resident populations. RESULTS: The resulting "Extinguish Tool" includes an interactive map of U.S. public housing developments (PHDs) and healthcare facilities that provides detailed information on individual PHDs, their proximity to existing healthcare facilities, and the demographic characteristics of residents. The tool also estimates the number of PHD residents who smoke cigarettes and calculates crude estimates of the potential economic benefits of providing cessation interventions to these residents. The geospatial mapping tool project serves as an example of a collaborative and innovative public health approach to protecting the health and well-being of the nation's two million public housing residents, including 760,000 children, from the harms of tobacco smoking and secondhand smoke exposure in the places where they live, play, and gather.

11.
Sci Rep ; 9(1): 15580, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31666590

RESUMO

Peripheral artery disease (PAD) is a major cause of acute and chronic illness, with extremely poor prognosis that remains underdiagnosed and undertreated. Trimethylamine-N-Oxide (TMAO), a gut derived metabolite, has been associated with atherosclerotic burden. We determined plasma levels of TMAO by mass spectrometry and evaluated their association with PAD severity and prognosis. 262 symptomatic PAD patients (mean age 70 years, 87% men) categorized in intermittent claudication (IC, n = 147) and critical limb ischemia (CLI, n = 115) were followed-up for a mean average of 4 years (min 1-max 102 months). TMAO levels were increased in CLI compared to IC (P < 0.001). Receiver operating characteristic (ROC) curves for severity (CLI) rendered a cutoff of 2.26 µmol/L for TMAO (62% sensitivity, 76% specificity). Patients with TMAO > 2.26 µmol/L exhibited higher risk of cardiovascular death (sub-hazard ratios ≥2, P < 0.05) that remained significant after adjustment for confounding factors. TMAO levels were associated to disease severity and CV-mortality in our cohort, suggesting an improvement of PAD prognosis with the measurement of TMAO. Overall, our results indicate that the intestinal bacterial function, together with the activity of key hepatic enzymes for TMA oxidation (FMO3) and renal function, should be considered when designing therapeutic strategies to control gut-derived metabolites in vascular patients.

12.
Proc Natl Acad Sci U S A ; 116(49): 24639-24650, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31754024

RESUMO

Proteasome-mediated degradation of intracellular proteins is essential for cell function and survival. The proteasome-binding protein PI31 (Proteasomal Inhibitor of 31kD) promotes 26S assembly and functions as an adapter for proteasome transport in axons. As localized protein synthesis and degradation is especially critical in neurons, we generated a conditional loss of PI31 in spinal motor neurons (MNs) and cerebellar Purkinje cells (PCs). A cKO of PI31 in these neurons caused axon degeneration, neuronal loss, and progressive spinal and cerebellar neurological dysfunction. For both MNs and PCs, markers of proteotoxic stress preceded axonal degeneration and motor dysfunction, indicating a critical role for PI31 in neuronal homeostasis. The time course of the loss of MN and PC function in developing mouse central nervous system suggests a key role for PI31 in human neurodegenerative diseases.

13.
Elife ; 82019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31612856

RESUMO

Alzheimer's disease (AD) pathology is characterized by plaques of amyloid beta (Aß) and neurofibrillary tangles of tau. Aß aggregation is thought to occur at early stages of the disease, and ultimately gives way to the formation of tau tangles which track with cognitive decline in humans. Here, we report the crystal structure of an Aß core segment determined by MicroED and in it, note characteristics of both fibrillar and oligomeric structure. Using this structure, we designed peptide-based inhibitors that reduce Aß aggregation and toxicity of already-aggregated species. Unexpectedly, we also found that these inhibitors reduce the efficiency of Aß-mediated tau aggregation, and moreover reduce aggregation and self-seeding of tau fibrils. The ability of these inhibitors to interfere with both Aß and tau seeds suggests these fibrils share a common epitope, and supports the hypothesis that cross-seeding is one mechanism by which amyloid is linked to tau aggregation and could promote cognitive decline.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31613938

RESUMO

This case report presents the preliminary results of combining a modification of the nonincised papillae surgical approach (NIPSA), attempting to improve outcomes in the treatment of teeth with advanced periodontal support loss. The modification added a connective tissue graft (CTG) in the buccal aspect of these unfavorable cases caused by deep buccal bone dehiscence, soft tissue deficiencies, or tooth malposition (especially when positioned outside the bony contour). Deep, intrabony, noncontained defects affecting the maxillary incisors were treated in four patients. At the 1-year follow-up, all cases showed an improvement in the marginal soft tissue with considerable reductions in periodontal pocket depth and gains in clinical attachment. NIPSA plus CTG seem to improve clinical outcomes in deep, noncontained intrabony defects.


Assuntos
Perda do Osso Alveolar , Transplantes , Tecido Conjuntivo , Seguimentos , Regeneração Tecidual Guiada Periodontal , Humanos , Perda da Inserção Periodontal , Bolsa Periodontal , Resultado do Tratamento
15.
Molecules ; 24(21)2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31652876

RESUMO

A fractional factorial design was used to evaluate the effects of temperature, frying time, blanching treatment and the thickness of potato slices on acrylamide content in crisps. The design was used on freshly harvested and four-month stored potatoes. The critical factors found were temperature and frying time, and the interaction between blanching treatment and slice thickness. Once frying conditions were selected, an acrylamide content of 725 and 1030 mg kg-1 was found for non-stored and 4-month stored tubers, with adequate textural parameters in both cases. The difference in concentration is related to storage conditions, which must be controlled in order to control acrylamide levels. Bioaccesibility studies demonstrated that acrylamide concentration remained at 70%, and reductions took place mainly at the intestinal phase, as a result of reaction with nucleophilic compounds.

16.
ACS Cent Sci ; 5(9): 1507-1513, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31572777

RESUMO

Here we apply microcrystal electron diffraction (MicroED) to the structural determination of transition-metal complexes. We find that the simultaneous use of 300 keV electrons, very low electron doses, and an ultrasensitive camera allows for the collection of data without cryogenic cooling of the stage. This technique reveals the first crystal structures of the classic zirconocene hydride, colloquially known as "Schwartz's reagent", a novel Pd(II) complex not amenable to solution-state NMR or X-ray crystallography, and five other paramagnetic and diamagnetic transition-metal complexes.

17.
Am J Case Rep ; 20: 1369-1372, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31523051

RESUMO

BACKGROUND Ecthyma gangrenosum is an uncommon cutaneous infection commonly caused by Pseudomonas aeruginosa affecting typically immunocompromised patients. The presence of ecthyma gangrenosum can be associated with severe systemic infection often with a fatal prognosis. Most cases of ecthyma gangrenosum occur around the axilla, buttocks, and limbs; the scrotum is rarely affected. CASE REPORT A 68-year-old male with previously diagnosed acute myeloid leukemia, presented with left scrotal pain, fever, and rigors. Physical examination showed 2 ulcerating lesions with central black eschars surrounded by erythematous halos on the superior aspect of the left scrotum. Diagnosis of ecthyma gangrenosum was confirmed as both blood and lesion cultures showed growth of P. aeruginosa. After early empiric antibiotic treatment, the lesions significantly improved, and no sign of recurrence or new lesions was noticed. CONCLUSIONS Ecthyma gangrenosum should be considered in the differential diagnosis of ulcerating lesions of the scrotum. An early diagnosis and aggressive antibiotic treatment are imperative for resolution of this infection.

18.
Orthopedics ; 42(6): 316-322, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31505019

RESUMO

Femoral component sizing and rotation in total knee arthroplasty (TKA) affects patellofemoral tracking and tibiofemoral mechanics. Posterior referencing is said to optimize restoration of posterior condylar offset. However, it typically allows the surgeon to select 3° to 5° of external rotation to the posterior condylar axis, inevitably changing the offset of one or both condyles. The axis about which external rotation occurs varies between the jigs of various TKA systems. The location of this axis can result in a medial, central, or lateral reference point for posterior offset restoration. Variations in jig design will result in varying posterior offset changes at the same jig setting, with differential effects on balance between the flexion and extension gaps. Using identical Sawbones in a controlled laboratory setting, 9 TKA instrumentation systems were examined. Two systems referenced medially, 1 referenced laterally, and 6 referenced centrally. The authors measured distal and posterior resections in both 3° and 5° of external rotation to the posterior condylar axis. They calculated changes in both distal and posterior joint lines using resection measurements and implant specifications. Posterior resection thicknesses were greatest with instruments that referenced laterally and least with instruments that referenced medially. With increasing external rotation, instruments that referenced off the lateral femoral condyle introduced the greatest mismatch between the distal and posterior joint lines, as compared with instruments that referenced centrally or medially. Surgeons should be aware that laterally referencing systems can differentially restore distal and posterior joint lines at higher settings of femoral external rotation, potentially introducing incongruity between flexion and extension gaps if the posterior slope of the tibia is maintained. This may be particularly problematic if flexion laxity is increased by posterior cruciate ligament sacrifice. [Orthopedics. 2019; 42(6):316-322.].

19.
Nat Struct Mol Biol ; 26(10): 988, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31530939

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

20.
Clin Adv Periodontics ; 9(3): 142-146, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31490044

RESUMO

INTRODUCTION: The peripheral giant cell granuloma (PGCG) is associated with periodontal bony lesions in several situations and excision results in a soft papilla defect and an intrabony defect without soft tissue protection. CASE PRESENTATION: A PGCG associated with loss of periodontal support is described. Following the lesion excision, a specific flap design outlining a surgical papilla in the adjacent area was proposed. The aim of this flap design was to obtain an optimal condition for periodontal regeneration, to treat the lesion excision associated with soft tissue defect, and to avoid a second surgical area. Complete periodontal defect resolution without soft tissue contraction or lesion recurrence was obtained at 2-year follow-up. CONCLUSION: Early diagnosis and treatment are essential to prevent greater loss of periodontal attachment.

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