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1.
Emerg Infect Dis ; 29(8): 1540-1546, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37486160

RESUMEN

Nontuberculous mycobacteria (NTM) infections are caused by environmental exposure. We describe spatial distribution of NTM infections and associations with sociodemographic factors and flooding in Missouri, USA. Our retrospective analysis of mycobacterial cultures reported to the Missouri Department of Health and Social Services surveillance system during January 1, 2008-December 31, 2019, detected geographic clusters of infection. Multilevel Poisson regression quantified small-area geographic variations and identified characteristics associated with risk for infection. Median county-level NTM infection rate was 66.33 (interquartile range 51-91)/100,000 persons. Risk of clustering was significantly higher in rural areas (rate ratio 2.82, 95% CI 1.90-4.19) and in counties with >5 floodings per year versus no flooding (rate ratio 1.38, 95% CI 1.26-1.52). Higher risk for NTM infection was associated with older age, rurality, and more flooding. Clinicians and public health professionals should be aware of increased risk for NTM infections, especially in similar environments.


Asunto(s)
Infecciones por Mycobacterium no Tuberculosas , Micobacterias no Tuberculosas , Humanos , Missouri/epidemiología , Infecciones por Mycobacterium no Tuberculosas/epidemiología , Infecciones por Mycobacterium no Tuberculosas/microbiología , Micobacterias no Tuberculosas/aislamiento & purificación , Micobacterias no Tuberculosas/fisiología , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Factores de Edad , Inundaciones , Población Rural , Masculino , Femenino , Persona de Mediana Edad , Anciano , Punto Alto de Contagio de Enfermedades
2.
J Neurooncol ; 163(3): 529-539, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37440095

RESUMEN

PURPOSE: Social determinants of health broadly affect healthcare access and outcomes. Studies report that minorities and low socioeconomic status (SES) patients undergoing intracranial meningioma resection demonstrate worse outcomes and higher mortality rates. This systematic review and meta-analysis summarizes the available research reporting racial and SES disparities in intracranial meningioma resection outcomes. METHODS: A systematic review was conducted using PRISMA guidelines and included peer-reviewed, English-language articles from the United States between 2000 and 2022 that reported racial and SES disparities in meningioma outcomes. Outcomes included overall survival (OS), extent of resection (EOR), hospitalization costs, length of stay (LOS), 30-day readmission, recurrence, and receipt of surgery and adjuvant radiotherapy. A quantitative meta-analysis was performed only on survival outcomes by race. All other variables were summarized as a systematic review. RESULTS: 633 articles were identified; 19 studies met inclusion criteria. Black or low SES patients were more likely to have increased hospitalization costs, rates of 30-day readmission, LOS, recurrence and less likely to undergo surgery, gross total resection, and adjuvant radiotherapy for their tumors. Six studies were used for the quantitative meta-analysis of race and OS. Compared to White patients, Black patients had significantly worse survival outcomes, and Asian patients had significantly better survival outcomes. CONCLUSION: Disparities in outcomes exist for patients who undergo surgery for meningioma, such that Black and low SES patients have worse outcomes. The literature is quite sparse and contains confounding relationships not often accounted for appropriately. Further studies are needed to help understand these disparities to improve outcomes.


Asunto(s)
Neoplasias Meníngeas , Meningioma , Humanos , Estados Unidos , Meningioma/patología , Clase Social , Hospitalización , Tiempo de Internación , Neoplasias Meníngeas/patología , Disparidades en Atención de Salud
3.
Clin Infect Dis ; 74(Suppl_3): S237-S243, 2022 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-35568480

RESUMEN

Social media (SoMe) platforms have been increasingly used by infectious diseases (ID) learners and educators in recent years. This trend has only accelerated with the changes brought to our educational spaces by the coronavirus disease 2019 pandemic. Given the increasingly diverse SoMe landscape, educators may find themselves struggling with how to effectively use these tools. In this Viewpoint we describe how to use SoMe platforms (e.g., Twitter, podcasts, and open-access online content portals) in medical education, highlight medical education theories supporting their use, and discuss how educators can engage with these learning tools effectively. We focus on how these platforms harness key principles of adult learning and provide a guide for educators in the effective use of SoMe tools in educating ID learners. Finally, we suggest how to effectively interact with and leverage these increasingly important digital platforms.


Asunto(s)
COVID-19 , Enfermedades Transmisibles , Educación Médica , Medios de Comunicación Sociales , Humanos , Aprendizaje
4.
J Clin Microbiol ; 60(4): e0226121, 2022 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-35291804

RESUMEN

Persistent Staphylococcus aureus bacteremia (SAB) has been associated with increased mortality. Enhanced microbial detection with new blood culture technology may improve detection of S. aureus in patients with SAB. We performed a 24-month retrospective study of hospitalized adults with SAB and an infectious diseases consult comparing two time periods pre- (January to December 2018) and postimplementation (January to December 2019) in which the VersaTREK and BacT/Alert Virtuo blood culture systems were used, respectively. Measurements included SAB duration, time to positivity, source of bacteremia, antimicrobial therapy, and mortality. A total of 416 episodes of SAB occurred during the study period: 176 (42%) pre- and 240 (58%) postimplementation. Patients in both periods had similar clinical characteristics; however, patients in the postimplementation period were more likely to have intermediate (3 to 6 days; 23% versus 40%; P < 0.001) and prolonged SAB duration (>7 days; 4% versus 14%; P < 0.001). Combination antistaphylococcal therapy was more frequent postimplementation (6.3% pre- versus 15.8% postimplementation; P = 0.003), and the median time to source control was shorter (4 versus 2 days; P = 0.02). Median time to positivity for the index blood culture was shorter postimplementation (17.8 h pre- versus 13.3 h postimplementation; P < 0.001). There was no difference in 90-day all-cause readmissions (51% versus 44%; P = 0.11) or mortality (32% versus 32%; P = 0.95). An increased frequency of prolonged SAB with increased use of combination antistaphylococcal therapy was noted with implementation of a new blood culture system, likely secondary to the blood culture media; however, no differences on adverse outcomes were noted.


Asunto(s)
Bacteriemia , Infecciones Estafilocócicas , Adulto , Antibacterianos/uso terapéutico , Bacteriemia/diagnóstico , Bacteriemia/tratamiento farmacológico , Cultivo de Sangre , Medios de Cultivo , Humanos , Estudios Retrospectivos , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus
5.
Respir Res ; 23(1): 198, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35915495

RESUMEN

BACKGROUND: Bangladesh introduced the 10-valent pneumococcal conjugate vaccine (PCV10) for children aged < 1 year in March 2015. Previous vaccine effectiveness (VE) studies for pneumonia have used invasive pneumococcal disease or chest X-rays. None have used ultrasound. We sought to determine the VE of PCV10 against sonographically-confirmed pneumonia in three subdistrict health complexes in Bangladesh. METHODS: We conducted a matched case-control study between July 2015 and September 2017 in three subdistricts of Sylhet, Bangladesh. Cases were vaccine-eligible children aged 3-35 months with sonographically-confirmed pneumonia, who were matched with two types of controls by age, sex, week of diagnosis, subdistrict health complex (clinic controls) or distance from subdistrict health complex (community controls) and had an illness unlikely due to Streptococcus pneumoniae (clinic controls) or were healthy (community controls). VE was measured using multivariable conditional logistic regression. RESULTS: We evaluated 8926 children (average age 13.3 months, 58% boys) with clinical pneumonia by ultrasound; 2470 had pneumonia with consolidations ≥ 1 cm; 1893 pneumonia cases were matched with 4238 clinic controls; and 1832 were matched with 3636 community controls. VE increased with the threshold used for consolidation size on ultrasound: the adjusted VE of ≥ 2 doses vs. non-recipients of PCV10 against pneumonia increased from 15.8% (95% CI 1.6-28.0%) for consolidations ≥ 1 cm to 29.6% (12.8-43.2%) for consolidations ≥ 1.5 cm using clinic controls and from 2.7% (- 14.2-17.2%) to 23.5% (4.4-38.8%) using community controls, respectively. CONCLUSIONS: PCV10 was effective at reducing sonographically-confirmed pneumonia in children aged 3-35 months of age when compared to unvaccinated children. VE increased with the threshold used for consolidation size on ultrasound in clinic and community controls alike. This study provides evidence that lung ultrasound is a useful alternative to chest X-ray for case-control studies evaluating the effectiveness of vaccines against pneumonia.


Asunto(s)
Neumonía Neumocócica , Neumonía , Bangladesh/epidemiología , Estudios de Casos y Controles , Niño , Femenino , Humanos , Lactante , Masculino , Vacunas Neumococicas , Neumonía Neumocócica/diagnóstico por imagen , Neumonía Neumocócica/prevención & control
6.
J Clin Microbiol ; 59(10): e0061721, 2021 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-34260277

RESUMEN

The bioMérieux BacT/Alert Virtuo blood culture system used in combination with resin-containing media may enhance the growth of microorganisms. Our objective was to assess the impact of transitioning to the Virtuo system in comparison to the VersaTREK blood culture system at a tertiary care medical center. We retrospectively reviewed all blood cultures performed at a 1,250-bed academic medical center between January and December 2018 (VersaTREK) and January and December 2019 (Virtuo). Blood culture positivity rates and contamination rates were compared before and after Virtuo implementation. Of 101,438 blood cultures performed during the study period, 48,839 (48.1%) were processed preimplementation and 52,599 (51.9%) postimplementation. The blood culture positivity rate increased from 8.1% preimplementation to 11.7% postimplementation (P < 0.001). Staphylococcus aureus was the most frequently isolated species in both time periods and had a higher recovery rate postimplementation (1.5% of all blood cultures obtained preimplementation versus 3.4% postimplementation; P < 0.001). A higher recovery rate in the postimplementation period was also noted for coagulase-negative staphylococci (1.9% preimplementation versus 2.7% postimplementation; P < 0.001), as well as modest but statistically significant changes for Escherichia coli (0.8% versus 1.0%; P < 0.001), Klebsiella pneumoniae (0.4% versus 0.5%; P = 0.005), and Candida albicans. (0.1% versus 0.2%; P = 0.038). The inpatient blood culture contamination rate was higher postimplementation (1.5% preimplementation versus 1.9% postimplementation; P < 0.001). The Virtuo blood culture system was associated with a higher observed proportion of positive blood cultures than the VersaTREK system. Future studies are needed to assess whether an increased rate of positive blood cultures is associated with changes in clinical outcomes.


Asunto(s)
Bacteriemia , Cultivo de Sangre , Bacteriemia/diagnóstico , Medios de Cultivo , Humanos , Estudios Retrospectivos , Staphylococcus aureus , Centros de Atención Terciaria
7.
J Biol Chem ; 294(9): 3012-3023, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30563839

RESUMEN

Mast cells (MCs) participate in allergy, inflammation, and defense against pathogens. They release multiple immune mediators via exocytosis, a process that requires SNARE proteins, including syntaxins (Stxs). The identity of the Stxs involved in MC exocytosis remains controversial. Here, we studied the roles of Stx3 and -4 in fully developed MCs from conditional knockout mice by electrophysiology and EM, and found that Stx3, and not Stx4, is crucial for MC exocytosis. The main defect seen in Stx3-deficient MCs was their inability to engage multigranular compound exocytosis, while leaving most single-vesicle fusion events intact. We used this defect to show that this form of exocytosis is not only required to accelerate MC degranulation but also essential to achieve full degranulation. The exocytic defect was severe but not absolute, indicating that an Stx other than Stx3 and -4 is also required for exocytosis in MCs. The removal of Stx3 affected only regulated exocytosis, leaving other MC effector responses intact, including the secretion of cytokines via constitutive exocytosis. Our in vivo model of passive systemic anaphylaxis showed that the residual exocytic function of Stx3-deficient MCs was sufficient to drive a full anaphylactic response in mice.


Asunto(s)
Exocitosis , Mastocitos/citología , Proteínas Qa-SNARE/metabolismo , Animales , Recuento de Células , Degranulación de la Célula , Diferenciación Celular , Técnicas de Inactivación de Genes , Cinética , Ratones , Proteínas Qa-SNARE/deficiencia , Proteínas Qa-SNARE/genética
8.
J Biol Chem ; 293(19): 7148-7159, 2018 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-29599294

RESUMEN

Mast cells (MCs) play pivotal roles in many inflammatory conditions including infections, anaphylaxis, and asthma. MCs store immunoregulatory compounds in their large cytoplasmic granules and, upon stimulation, secrete them via regulated exocytosis. Exocytosis in many cells requires the participation of Munc18 proteins (also known as syntaxin-binding proteins), and we found that mature MCs express all three mammalian isoforms: Munc18-1, -2, and -3. To study their functions in MC effector responses and test the role of MC degranulation in anaphylaxis, we used conditional knockout (cKO) mice in which each Munc18 protein was deleted exclusively in MCs. Using recordings of plasma membrane capacitance for high-resolution analysis of exocytosis in individual MCs, we observed an almost complete absence of exocytosis in Munc18-2-deficient MCs but intact exocytosis in MCs lacking Munc18-1 or Munc18-3. Stereological analysis of EM images of stimulated MCs revealed that the deletion of Munc18-2 also abolishes the homotypic membrane fusion required for compound exocytosis. We confirmed the severe defect in regulated exocytosis in the absence of Munc18-2 by measuring the secretion of mediators stored in MC granules. Munc18-2 cKO mice had normal morphology, development, and distribution of their MCs, indicating that Munc18-2 is not essential for the migration, retention, and maturation of MC-committed progenitors. Despite that, we found that Munc18-2 cKO mice were significantly protected from anaphylaxis. In conclusion, MC-regulated exocytosis is required for the anaphylactic response, and Munc18-2 is the sole Munc18 isoform that mediates membrane fusion during MC degranulation.


Asunto(s)
Exocitosis/fisiología , Mastocitos/metabolismo , Proteínas Munc18/fisiología , Anafilaxia/fisiopatología , Animales , Degranulación de la Célula , Eliminación de Gen , Mastocitos/ultraestructura , Fusión de Membrana/fisiología , Ratones Endogámicos C57BL , Ratones Noqueados , Microscopía Electrónica , Proteínas Munc18/genética , Técnicas de Placa-Clamp
9.
J Nat Prod ; 82(2): 283-292, 2019 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-30694059

RESUMEN

Four new chalcones (1, 10, 13, and 14), a new flavanone, (9), a new amide (8), and 19 known compounds were acquired from Melodorum siamensis. The structures were established by NMR and MS data analyses. Compounds 1 (er 1.4:1) and 2 (er 1.1:1) were scalemic and were resolved to yield (-)-1 and (+)-1 and (-)-2 and (+)-2, respectively. The absolute configurations of these compounds were determined from experimental and calculated ECD data. The structures and configurations of (-)-2 and (+)-8 were identified by single-crystal X-ray diffraction analysis. Compound 11 showed nuclear factor-κB inhibitory effects (IC50 = 9 µM) in a pancreatic ß cell line (MIN-6 cells).


Asunto(s)
Amidas/aislamiento & purificación , Annonaceae/química , Flavonoides/aislamiento & purificación , Transporte Activo de Núcleo Celular/efectos de los fármacos , Amidas/química , Amidas/farmacología , Línea Celular , Flavonoides/química , Flavonoides/farmacología , Frutas/química , Humanos , Espectroscopía de Resonancia Magnética , FN-kappa B/antagonistas & inhibidores , FN-kappa B/metabolismo , Extractos Vegetales/análisis , Hojas de la Planta/química
10.
Respiration ; 98(1): 60-69, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30799409

RESUMEN

BACKGROUND: Granulation tissue is a common complication of airway stenting, but no published methods can quantify the volume and type of tissue that develops. OBJECTIVE: To use design-based stereology to quantify changes in tissue volume and type associated with airway stenting. METHODS: We compared drug-eluting stents (DES) filled with gendine to standard silicone stents in pigs in an assessor-blinded randomized trial. Tracheal stents were placed via rigid bronchoscopy. After 1 month, animals were euthanized and necropsies were performed. Antimicrobial effects of the DES were assessed in trachea tissue samples, on the DES surface, and with residual gel from the DES reservoir. Tracheal thickness was measured using orthogonal intercepts. Design-based stereology was used to quantify the volume density of tissues using a point-counting method. The volume of each tissue was normalized to cartilage volume, which is unaffected by stenting. RESULTS: Pigs were randomized to DES (n = 36) or control stents (n = 9). The drug was successfully eluted from the DES, and the stent surface showed antibacterial activity. DES and controls did not differ in tissue microbiology, tracheal thickness, or granulation tissue volume. Compared to nonstented controls, stented airways demonstrated a 110% increase in soft-tissue volume (p = 0.005). Submucosal connective tissue (118%; p < 0.0001), epithelium (70%; p < 0.0001), submucosal glands (47%; p = 0.001), and smooth muscle (41%; p < 0.0001) increased in volume. CONCLUSION: Stenting doubles the volume of soft tissue in the trachea. Design-based stereology can quantify the tissue changes associated with airway stenting.


Asunto(s)
Stents Liberadores de Fármacos/efectos adversos , Tejido de Granulación/diagnóstico por imagen , Tejido de Granulación/patología , Tráquea/diagnóstico por imagen , Tráquea/patología , Animales , Broncoscopía , Modelos Animales de Enfermedad , Humanos , Procesamiento de Imagen Asistido por Computador , Distribución Aleatoria , Porcinos , Tráquea/cirugía
11.
J Nat Prod ; 81(10): 2244-2250, 2018 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-30350994

RESUMEN

Biotransformation of ß-mangostin (1) by the endophytic fungus Xylaria feejeensis GM06 afforded hexacyclic ring-fused xanthenes with an unprecedented hexacyclic heterocylic skeleton. ß-Mangostin (1) was transformed to two diastereomeric pairs of enantiomers, mangostafeejin A [(-)-2a/(+)-2b)] and mangostafeejin B [(-)-3a/(+)-3b)]. The chemical structures of the transformation products were elucidated by analysis of NMR and MS data, and the structure of mangostafeejin A [(-)-2a/(+)-2b)] was confirmed by single-crystal X-ray diffraction analysis. The absolute configurations of 3a and 3b were established on the basis of calculated and measured ECD data using the ECD spectra of 2a and 2b as models. The fungal biotransformation described herein provides an effective method to convert an abundant achiral plant natural product scaffold into new chiral heterocyclic scaffolds representing expanded chemical diversity for biological activity screening.


Asunto(s)
Ácidos Heterocíclicos/síntesis química , Garcinia mangostana/microbiología , Xantenos/síntesis química , Xantonas/metabolismo , Xylariales/metabolismo , Biotransformación , Dicroismo Circular , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Estructura Molecular , Estereoisomerismo , Difracción de Rayos X
12.
Lung ; 193(4): 531-8, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25921013

RESUMEN

PURPOSE: The World Health Organization (WHO) case management algorithm for acute lower respiratory infections has moderate sensitivity and poor specificity for the diagnosis of pneumonia. We sought to determine the feasibility of using point-of-care ultrasound in resource-limited settings to identify pneumonia by general health practitioners and to determine agreement between the WHO algorithm and lung consolidations identified by point-of-care ultrasound. METHODS: An expert radiologist taught two general practitioners how to perform point-of-care ultrasound over a seven-day period. We then conducted a prospective study of children aged 2 months to 3 years in Peru and Nepal with and without respiratory symptoms, which were evaluated by point-of-care ultrasound to identify lung consolidation. RESULTS: We enrolled 378 children: 127 were controls without respiratory symptoms, 82 had respiratory symptoms without clinical pneumonia, and 169 had clinical pneumonia by WHO criteria. Point-of-care ultrasound was performed in the community (n = 180), in outpatient offices (n = 95), in hospital wards (n = 19), and in Emergency Departments (n = 84). Average time to perform point-of-care ultrasound was 6.4 ± 2.2 min. Inter-observer agreement for point-of-care ultrasound interpretation between general practitioners was high (κ = 0.79, 95 % CI 0.73-0.81). The diagnosis of pneumonia using the WHO algorithm yielded a sensitivity of 69.6 % (95 % CI 55.7-80.8 %), specificity of 59.6 % (95 % CI 54.0-65.0 %), and positive and negative likelihood ratios of 1.73 (95 % CI 1.39-2.15) and 0.51 (95 % CI 0.30-0.76) when lung consolidation on point-of-care ultrasound was used as the reference. CONCLUSIONS: The WHO algorithm disagreed with point-of-care ultrasound findings in more than one-third of children and had an overall low performance when compared with point-of-care ultrasound to identify lung consolidation. A paired approach with point-of-care ultrasound may improve case management in resource-limited settings.


Asunto(s)
Algoritmos , Países en Desarrollo , Medicina General , Neumonía/diagnóstico por imagen , Preescolar , Femenino , Humanos , Lactante , Masculino , Nepal , Variaciones Dependientes del Observador , Perú , Sistemas de Atención de Punto , Estudios Prospectivos , Sensibilidad y Especificidad , Ultrasonografía , Organización Mundial de la Salud
13.
Respir Res ; 15: 50, 2014 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-24758612

RESUMEN

BACKGROUND: Guidelines do not currently recommend the use of lung ultrasound (LUS) as an alternative to chest X-ray (CXR) or chest computerized tomography (CT) scan for the diagnosis of pneumonia. We conducted a meta-analysis to summarize existing evidence of the diagnostic accuracy of LUS for pneumonia in adults. METHODS: We conducted a systematic search of published studies comparing the diagnostic accuracy of LUS against a referent CXR or chest CT scan and/or clinical criteria for pneumonia in adults aged ≥18 years. Eligible studies were required to have a CXR and/or chest CT scan at the time of evaluation. We manually extracted descriptive and quantitative information from eligible studies, and calculated pooled sensitivity and specificity using the Mantel-Haenszel method and pooled positive and negative likelihood ratios (LR) using the DerSimonian-Laird method. We assessed for heterogeneity using the Q and I2 statistics. RESULTS: Our initial search strategy yielded 2726 articles, of which 45 (1.7%) were manually selected for review and 10 (0.4%) were eligible for analyses. These 10 studies provided a combined sample size of 1172 participants. Six studies enrolled adult patients who were either hospitalized or admitted to Emergency Departments with suspicion of pneumonia and 4 studies enrolled critically-ill adult patients. LUS was performed by highly-skilled sonographers in seven studies, by trained physicians in two, and one did not mention level of training. All studies were conducted in high-income settings. LUS took a maximum of 13 minutes to conduct. Nine studies used a 3.5-5 MHz micro-convex transducer and one used a 5-9 MHz convex probe. Pooled sensitivity and specificity for the diagnosis of pneumonia using LUS were 94% (95% CI, 92%-96%) and 96% (94%-97%), respectively; pooled positive and negative LRs were 16.8 (7.7-37.0) and 0.07 (0.05-0.10), respectively; and, the area-under-the-ROC curve was 0.99 (0.98-0.99). CONCLUSIONS: Our meta-analysis supports that LUS, when conducted by highly-skilled sonographers, performs well for the diagnosis of pneumonia. General practitioners and Emergency Medicine physicians should be encouraged to learn LUS since it appears to be an established diagnostic tool in the hands of experienced physicians.


Asunto(s)
Pulmón/diagnóstico por imagen , Neumonía/diagnóstico por imagen , Adulto , Ensayos Clínicos como Asunto , Humanos , Tomografía Computarizada por Rayos X/métodos , Tomografía Computarizada por Rayos X/normas , Ultrasonografía
14.
J Org Chem ; 79(8): 3327-35, 2014 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-24684453

RESUMEN

Extracts of laboratory cultures of the fungus Penicilium purpurogenum obtained from rotting fruit of the tree Averrhoa bilimbi growing in Sri Lanka have yielded 10 new meroterpenoids, dhilirolides E-N (5-14). The structures of the new dhilirolides have been elucidated by analysis of spectroscopic data and a single-crystal X-ray diffraction analysis of dhilirolide L (12). Dhilirolides A-N (1-14) represent the four unprecedented and rearranged dhilirane, isodhilirane, 14,15-dinordhilirane, and 23,24-dinorisodhilirane meroterpenoid carbon skeletons. Stable isotope feeding studies have confirmed the meroterpenoid biogenetic origin of the dhilirolides and provided support for a proposed genesis of the new carbon skeletons. Dhilirolide L (12) showed significant feeding inhibition and sublethal developmental disruption in the cabbage looper Trichoplusia ni, an important agricultural pest, at low concentrations.


Asunto(s)
Insecticidas/química , Isótopos/química , Penicillium/química , Terpenos/química , Animales , Estructura Molecular , Sri Lanka , Difracción de Rayos X
15.
Lung ; 192(5): 765-73, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24943262

RESUMEN

PURPOSE: Lung auscultation has long been a standard of care for the diagnosis of respiratory diseases. Recent advances in electronic auscultation and signal processing have yet to find clinical acceptance; however, computerized lung sound analysis may be ideal for pediatric populations in settings, where skilled healthcare providers are commonly unavailable. We described features of normal lung sounds in young children using a novel signal processing approach to lay a foundation for identifying pathologic respiratory sounds. METHODS: 186 healthy children with normal pulmonary exams and without respiratory complaints were enrolled at a tertiary care hospital in Lima, Peru. Lung sounds were recorded at eight thoracic sites using a digital stethoscope. 151 (81%) of the recordings were eligible for further analysis. Heavy-crying segments were automatically rejected and features extracted from spectral and temporal signal representations contributed to profiling of lung sounds. RESULTS: Mean age, height, and weight among study participants were 2.2 years (SD 1.4), 84.7 cm (SD 13.2), and 12.0 kg (SD 3.6), respectively; and, 47% were boys. We identified ten distinct spectral and spectro-temporal signal parameters and most demonstrated linear relationships with age, height, and weight, while no differences with genders were noted. Older children had a faster decaying spectrum than younger ones. Features like spectral peak width, lower-frequency Mel-frequency cepstral coefficients, and spectro-temporal modulations also showed variations with recording site. CONCLUSIONS: Lung sound extracted features varied significantly with child characteristics and lung site. A comparison with adult studies revealed differences in the extracted features for children. While sound-reduction techniques will improve analysis, we offer a novel, reproducible tool for sound analysis in real-world environments.


Asunto(s)
Auscultación/normas , Pulmón/fisiología , Ruidos Respiratorios , Factores de Edad , Auscultación/instrumentación , Estatura , Peso Corporal , Preescolar , Femenino , Humanos , Lactante , Masculino , Perú , Valor Predictivo de las Pruebas , Valores de Referencia , Factores Sexuales , Procesamiento de Señales Asistido por Computador , Espectrografía del Sonido , Estetoscopios/normas , Factores de Tiempo
16.
ScientificWorldJournal ; 2014: 363274, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25054176

RESUMEN

Aeroelastic effects are relatively common in the design of modern civil constructions such as office blocks, airport terminal buildings, and factories. Typical flexible structures exposed to the action of wind are shading devices, normally slats or louvers. A typical cross-section for such elements is a Z-shaped profile, made out of a central web and two-side wings. Galloping instabilities are often determined in practice using the Glauert-Den Hartog criterion. This criterion relies on accurate predictions of the dependence of the aerodynamic force coefficients with the angle of attack. The results of a parametric analysis based on a numerical analysis and performed on different Z-shaped louvers to determine translational galloping instability regions are presented in this paper. These numerical analysis results have been validated with a parametric analysis of Z-shaped profiles based on static wind tunnel tests. In order to perform this validation, the DLR TAU Code, which is a standard code within the European aeronautical industry, has been used. This study highlights the focus on the numerical prediction of the effect of galloping, which is shown in a visible way, through stability maps. Comparisons between numerical and experimental data are presented with respect to various meshes and turbulence models.


Asunto(s)
Materiales de Construcción , Modelos Teóricos , Viento
17.
Infect Control Hosp Epidemiol ; 45(3): 384-386, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37800346

RESUMEN

We implemented 2 interventions to improve utilization and contamination at our institution: kits to improve appropriate sample collection and an electronic order alert displaying appropriate indications of fungal blood cultures. An electronic order alert when ordering fungal blood cultures was associated with decreased utilization without decrease in positivity rate.


Asunto(s)
Cultivo de Sangre , Registros , Humanos
18.
J Neurosurg ; : 1-9, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38518289

RESUMEN

OBJECTIVE: The influence of socioeconomic factors on racial disparities among patients with sporadic meningiomas is well established, yet other potential causative factors warrant further exploration. The authors of this study aimed to determine whether there is significant variation in the genomic profile of meningiomas among patients of different races and ethnicities and its correlation with clinical outcomes. METHODS: The demographic, genomic, and clinical data of patients aged 18 years and older who had undergone surgery for sporadic meningioma between September 2008 and November 2021 were analyzed. Statistical analyses were performed to detect differences across all racial/ethnic groups, as were direct comparisons between Black and non-Black groups plus Hispanic and non-Hispanic groups. RESULTS: This study included 460 patients with intracranial meningioma. Hispanic patients were significantly younger at surgery (53.9 vs 60.2 years, p = 0.0006) and more likely to show symptoms. Black patients had a higher incidence of anterior skull base tumors (OR 3.2, 95% CI 1.7-6.3, p = 0.0008) and somatic hedgehog mutations (OR 5.3, 95% CI 1.6-16.6, p = 0.003). Hispanics were less likely to exhibit the aggressive genomic characteristic of chromosome 1p deletion (OR 0.28, 95% CI 0.07-1.2, p = 0.06) and displayed higher rates of TRAF7 somatic driver mutations (OR 2.96 95% CI 1.1-7.8, p = 0.036). Black patients had higher rates of recurrence (OR 2.6, 95% CI 1.3-5.2, p = 0.009) and shorter progression-free survival (PFS; HR 2.9, 95% CI 1.6-5.4, p = 0.002) despite extents of resection (EORs) similar to those of non-Black patients (p = 0.745). No significant differences in overall survival were observed among groups. CONCLUSIONS: Despite similar EORs, Black patients had worse clinical outcomes following meningioma resection, characterized by a higher prevalence of somatic hedgehog mutations, increased recurrence rates, and shorter PFS. Meanwhile, Hispanic patients had less aggressive meningiomas, a predisposition for TRAF7 mutations, and no difference in PFS. These findings could inform the care and treatment strategies for meningiomas, and they establish the foundation for future studies focusing on the genomic origins of these observed differences.

19.
J Org Chem ; 78(17): 8267-73, 2013 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-23941043

RESUMEN

Four new sesterterpenoids, ansellone B (4), phorbadione (5), secoepoxyansellone A (6), and alotaketal C (7), have been isolated from specimens of the sponge Phorbas sp. collected in British Columbia. Ansellone B (4) has an unprecedented heterocyclic skeleton featuring an oxocane ring, and secoepoxyansellone A (6) is the first example of the degraded "secoansellane" sesterterpenoid carbon skeleton. Alotaketal C (7) is an activator of cAMP signaling in HEK cells.


Asunto(s)
Poríferos/química , Sesterterpenos/aislamiento & purificación , Animales , AMP Cíclico/metabolismo , Relación Dosis-Respuesta a Droga , Células HEK293 , Humanos , Conformación Molecular , Sesterterpenos/química , Sesterterpenos/farmacología , Transducción de Señal/efectos de los fármacos , Estereoisomerismo , Relación Estructura-Actividad
20.
J Surg Case Rep ; 2023(9): rjad491, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37680994

RESUMEN

The bipedicled Deep Inferior Epigastric Perforator (DIEP) flap, originally described and primarily utilized in autologous breast reconstruction for specific cases, has expanded its applications to encompass diverse anatomical regions in recent years. This report presents the case of a 69-year-old woman with a recurrent giant thyroid tumor who underwent surgical resection, resulting in a large cervico-thoracic defect effectively reconstructed using a bipedicled DIEP flap. The patient's postoperative recovery was uneventful, and the follow-up assessments revealed a healthy, well-perfused flap that provided sufficient coverage to critical structures, adequate restoration of the region contour, and enough volume to offset potential adverse effects of subsequent radiation therapy. In addition, this report incorporates a concise literature review highlighting the expanding indications of the bipedicled DIEP flap beyond breast reconstruction, showing the versatility and efficacy of the bipedicled DIEP flap in addressing complex soft-tissue defects in various anatomical areas.

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