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1.
Telemed J E Health ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38916876

RESUMEN

Background: The COVID-19 pandemic accelerated the formal integration of telehealth into education curricula and training programs, prompting the need to reevaluate the current landscape and inform a research agenda. We developed a survey to assess telehealth education and training curriculum, competencies, certification, and research across pediatric medical centers. Methods: Questions were derived from a previously published national survey and de novo. The survey was distributed across national pediatric professional associations. Results: In total, 32 respondents representing medical centers (86.5%) were providing telehealth education and/or training. Most were internally developed didactic (78.6%) and experiential (64.3%) curricula. Respondents who included education and/or training in telehealth research protocols and conducted telehealth research (74%) reported mandatory or optional training in tele-research. A form of certification was preferred by most organizations (>60%). Conclusion: Telehealth education and training are key factors within current and future service development, provision, and research to demonstrate competencies and positively impact patient care.

2.
Telemed J E Health ; 30(6): 1559-1573, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38563764

RESUMEN

Introduction: The surge in virtual care during the pandemic was accompanied by an increase in telehealth data of interest to policy stakeholders and other health care decision makers. However, these data often require substantial preprocessing and targeted analyses to be usable. By deliberately evaluating telehealth services with stakeholder perspectives in mind, telehealth researchers can more effectively inform clinical and policy decision making. Objective: To examine existing literature on telehealth measurement and evaluation and develop a new policy-oriented framework to guide telehealth researchers. Materials and Methods: A systematic rapid review of literature on telehealth measurement and evaluation was conducted by two independent reviewers in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The findings were analyzed and applied to the Supporting Pediatric Research on Outcomes and Utilization of Telehealth Evaluation and Measurement (STEM) Framework through the lens of key health care delivery decision makers to create a STEM Policy Framework Results: An initial search yielded 2,324 peer-reviewed articles and gray literatyre from 2012 to 2022, of which 56 met inclusion criteria. These measured and evaluated telehealth access (41.5%), quality (32.1%), cost (15.1%), experience (5.7%), and utilization (5.7%), consistent with the STEM Framework domains, but there was no universal approach. The STEM Policy Framework focuses this literature by describing data measures for each domain from the perspectives of five stakeholders. Conclusions: Literature describing measurement and evaluation approaches for telehealth is limited and not standardized, with few considering policy stakeholder perspectives. With this proposed STEM Policy Framework, we aim to improve this body of literature and support researchers seeking to inform telehealth policy through their work.


Asunto(s)
Política de Salud , Telemedicina , Telemedicina/organización & administración , Humanos , COVID-19/epidemiología , Participación de los Interesados , Formulación de Políticas
3.
Pediatr Neurosurg ; 58(5): 259-266, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36642062

RESUMEN

BACKGROUND: Diffuse intrinsic pontine gliomas (DIPGs) are high-grade gliomas (HGGs) that occur primarily in children, and represent a leading cause of death in pediatric patients with brain tumors with a median overall survival of only 8-11 months. SUMMARY: While these lesions were previously thought to behave similarly to adult HGG, emerging data have demonstrated that DIPG is a biologically distinct entity from adult HGG frequently driven by mutations in the histone genes H3.3 and H3.1 not found in adult glioma. While biopsy of DIPG was historically felt to confer unacceptable risk of morbidity and mortality, multiple studies have demonstrated that stereotactic biopsy of DIPG is safe, allowing not only for improved understanding of DIPG but also forming the basis for protocols for personalized medicine in DIPG. However, current options for personalized medicine in DIPG are limited by the lack of efficacious targeted therapies for the mutations commonly found in DIPG. Multiple treatment modalities including targeted therapies, immunotherapy, convection-enhanced delivery, and focused ultrasound are in various stages of investigation. KEY MESSAGE: Increasing frequency of biopsy for DIPG has identified distinct driving mutations that may serve as therapeutic targets. Novel treatment modalities are under investigation.


Asunto(s)
Neoplasias del Tronco Encefálico , Glioma Pontino Intrínseco Difuso , Glioma , Adulto , Niño , Humanos , Neoplasias del Tronco Encefálico/diagnóstico por imagen , Neoplasias del Tronco Encefálico/genética , Neoplasias del Tronco Encefálico/terapia , Glioma Pontino Intrínseco Difuso/genética , Glioma Pontino Intrínseco Difuso/terapia , Glioma Pontino Intrínseco Difuso/patología , Glioma/diagnóstico por imagen , Glioma/genética , Glioma/terapia , Inmunoterapia , Ensayos Clínicos como Asunto
4.
Telemed J E Health ; 28(8): 1178-1185, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-34967677

RESUMEN

Background: The COVID-19 pandemic accelerated the development of telehealth services and thus the need for telehealth education and training to support rapid implementation at scale. A national survey evaluating the current state of the telehealth landscape was deployed to organizational representatives, and included questions related to education and training. Materials and Methods: In the summer of 2020, 71 survey participants (31.8%) completed an online survey seeking to determine the utilization of telehealth services across institutional types and locations. This included data collected to specifically compare the rates and types of formal telehealth education provided before and during the pandemic. Results: Thirty percent of organizations reported no telehealth training before COVID-19, with those in suburban/rural settings significantly less likely to provide any training (55% vs. 82%) compared with urban. Pandemic-related training changes applied to 78% of organizations, with more change happening to those without any training before COVID-19 (95%). Generally, organizations offering training before the pandemic reported deploying COVID-19-related telehealth services, while a higher percentage of those without any training beforehand reported that they either did not plan on providing these services or were in the early planning stages. Discussion: Telehealth education is moving from elective to essential based on the need to prepare and certify the workforce to support high-quality telehealth services. Conclusions: As telehealth continues to evolve to meet the future health care service needs of patients and providers, education and training will advance to meet the needs of everyday clinical encounters and broader public health initiatives.


Asunto(s)
COVID-19 , Telemedicina , COVID-19/epidemiología , Humanos , Pandemias , Población Rural
5.
Cancer Metastasis Rev ; 39(1): 245-260, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31989507

RESUMEN

Pediatric high-grade gliomas (pHGGs) are a group of tumors affecting approximately 0.85 children per 100,000 annually. The general outcome for these tumors is poor with 5-year survival rates of less than 20%. It is now recognized that these tumors represent a heterogeneous group of tumors rather than one entity. Large-scale genomic analyses have led to a greater understanding of the molecular drivers of different subtypes of these tumors and have also aided in the development of subtype-specific therapies. For example, for pHGG with NTRK fusions, promising new targeted therapies are actively being explored. Herein, we review the clinico-pathologic and molecular classification of these tumors, historical treatments, current management strategies, and therapies currently under investigation.


Asunto(s)
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Glioma/genética , Glioma/terapia , Neoplasias Encefálicas/patología , Niño , Ensayos Clínicos como Asunto , Glioma/patología , Humanos , Clasificación del Tumor
6.
Pediatr Blood Cancer ; 68(10): e29172, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34125480

RESUMEN

BACKGROUND: Central nervous system (CNS) germinomas are treatment-sensitive tumors with excellent survival outcomes. Current treatment strategies combine chemotherapy with radiotherapy (RT) in order to reduce the field and dose of RT. Germinomas originating in the basal ganglia/thalamus (BGTGs) have proven challenging to treat given their rarity and poorly defined imaging characteristics. Craniospinal (CSI), whole brain (WBI), whole ventricle (WVI), and focal RT have all been utilized; however, the best treatment strategy remains unclear. METHODS: Retrospective multi-institutional analysis has been conducted across 18 institutions in four countries. RESULTS: For 43 cases of nonmetastatic BGTGs, the 5- and 10-year event-free survivals (EFS) were 85.8% and 81.0%, respectively, while the 5- and 10-year overall survivals (OS) were 100% and 95.5%, respectively (one patient fatality from unrelated cause). Median RT doses were as follows: CSI: 2250 cGy/cGy(RBE) (1980-2400); WBI: 2340 cGy/cGy(RBE) (1800-3000); WVI: 2340 cGy/cGy(RBE) (1800-2550); focal: 3600 cGy (3060-5400). Thirty-eight patients (90.5%) received chemotherapy. There was no statistically significant difference in the EFS based on initial field extent (p = .84). Nevertheless, no relapses were reported in patients who received CSI or WBI. Chemotherapy alone had significantly inferior EFS compared to combined therapy (p = .0092), but patients were salvageable with RT. CONCLUSION: Patients with BGTGs have excellent outcomes and RT proved to be an integral component of the treatment plan. This group of patients should be included in future prospective clinical trials and the best RT field should be investigated further.


Asunto(s)
Neoplasias Encefálicas , Neoplasias del Sistema Nervioso Central , Germinoma , Ganglios Basales/patología , Neoplasias Encefálicas/radioterapia , Germinoma/radioterapia , Humanos , Recurrencia Local de Neoplasia , Dosificación Radioterapéutica , Estudios Retrospectivos , Tálamo/diagnóstico por imagen
7.
Molecules ; 25(4)2020 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-32079271

RESUMEN

Cranberry is a well-known functional food, but the compounds directly responsible for many of its reported health benefits remain unidentified. Complex carbohydrates, specifically xyloglucan and pectic oligosaccharides, are the newest recognized class of biologically active compounds identified in cranberry materials. Cranberry oligosaccharides have shown similar biological properties as other dietary oligosaccharides, including effects on bacterial adhesion, biofilm formation, and microbial growth. Immunomodulatory and anti-inflammatory activity has also been observed. Oligosaccharides may therefore be significant contributors to many of the health benefits associated with cranberry products. Soluble oligosaccharides are present at relatively high concentrations (~20% w/w or greater) in many cranberry materials, and yet their possible contributions to biological activity have remained unrecognized. This is partly due to the inherent difficulty of detecting these compounds without intentionally seeking them. Inconsistencies in product descriptions and terminology have led to additional confusion regarding cranberry product composition and the possible presence of oligosaccharides. This review will present our current understanding of cranberry oligosaccharides and will discuss their occurrence, structures, ADME, biological properties, and possible prebiotic effects for both gut and urinary tract microbiota. Our hope is that future investigators will consider these compounds as possible significant contributors to the observed biological effects of cranberry.


Asunto(s)
Oligosacáridos/farmacología , Extractos Vegetales/farmacología , Vaccinium macrocarpon/química , Adhesión Bacteriana/efectos de los fármacos , Alimentos Funcionales , Humanos , Microbiota/efectos de los fármacos , Oligosacáridos/química , Extractos Vegetales/química , Espectroscopía de Protones por Resonancia Magnética
8.
J Neurooncol ; 144(3): 445-452, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31502040

RESUMEN

PURPOSE: The purpose of this study was to determine outcomes in recurrent pediatric ependymoma. METHODS: We performed a systematic review of PubMed, Embase, Web of Science and the Cochrane Library for studies reporting on survival outcomes for pediatric patients with recurrent ependymoma. We then performed a meta-analysis of all eligible results. Survival outcomes were identified across location of recurrence, therapy at recurrence, and age at recurrence. RESULTS: Eleven studies met final inclusion criteria. Pooled median progression free survival (PFS) from date of first recurrence was 6.7 months (95% confidence interval [95% CI] 4.7-8.8). Pooled median overall survival (OS) from date of first recurrence was 11.2 months (95% CI 6.4-16.0). Participants with supratentorial recurrences demonstrated a shorter OS of 8.3 months (95% CI 3.2-13.3) compared to 20.1 months (95% CI 8.4-31.7) for those with infratentorial recurrence. Patients who underwent surgery at recurrence had a median OS of 24.2 months (95% CI 14.2-34.1) compared to 29.2 months (95% CI 17.4-41.1) in those who received radiation compared to 19.3 months (95% CI 10.3-28.3) in those who received chemotherapy. Patients younger than age 3 years at time of recurrence demonstrated a median OS of 31.0 months (95% CI - 25.3-87.3) compared to 17.5 months (95% CI 9.9-25.2) for those that recurred beyond 3 years of age. CONCLUSIONS: Our findings illustrate that children with recurrent ependymoma suffer from poor outcomes; however, these outcomes range widely depending on patient, tumor, and treatment characteristics. New therapies and treatment strategies are needed to improve outcomes in this group.


Asunto(s)
Ependimoma/mortalidad , Recurrencia Local de Neoplasia/mortalidad , Niño , Terapia Combinada , Ependimoma/terapia , Humanos , Recurrencia Local de Neoplasia/terapia , Tasa de Supervivencia , Resultado del Tratamiento
9.
J Nat Prod ; 82(3): 589-605, 2019 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-30873836

RESUMEN

Cranberry ( Vaccinium macrocarpon) juice is traditionally used for the prevention of urinary tract infections. Human urine produced after cranberry juice consumption can prevent Escherichia coli adhesion, but the antiadhesive urinary metabolites responsible have not been conclusively identified. Adult female sows were therefore fed spray-dried cranberry powder (5 g/kg/day), and urine was collected via catheter. Urine fractions were tested for antiadhesion activity using a human red blood cell (A+) anti-hemagglutination assay with uropathogenic P-fimbriated E. coli. Components were isolated from fractions of interest using Sephadex LH-20 gel filtration chromatography followed by HPLC on normal and reversed-phase sorbents with evaporative light scattering detection. Active urine fractions were found to contain a complex series of oligosaccharides but not proanthocyanidins, and a single representative arabinoxyloglucan octasaccharide was isolated in sufficient quantity and purity for full structural characterization by chemical derivatization and NMR spectroscopic methods. Analogous cranberry material contained a similar complex series of arabinoxyloglucan oligosaccharides that exhibited antiadhesion properties in preliminary testing. These results indicate that oligosaccharides structurally related to those found in cranberry may contribute to the antiadhesion properties of urine after cranberry consumption.


Asunto(s)
Adhesión Bacteriana/efectos de los fármacos , Glucanos/farmacología , Oligosacáridos/farmacología , Orina , Escherichia coli Uropatógena/efectos de los fármacos , Vaccinium macrocarpon , Xilanos/farmacología , Animales , Glucanos/química , Oligosacáridos/química , Porcinos , Escherichia coli Uropatógena/fisiología , Xilanos/química
10.
J Nat Prod ; 82(3): 606-620, 2019 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-30839212

RESUMEN

Cranberry ( Vaccinium macrocarpon) products are widely available in North American food, juice, and dietary supplement markets. The use of cranberry is popular for the prevention of urinary tract infections (UTIs) and other reported health benefits. Preliminary findings by our research group indicate that arabinoxyloglucan oligosaccharides are present in cranberry products and may contribute to the antiadhesion properties of urine produced after cranberry consumption, but relatively little is known regarding the oligosaccharide components of cranberry. This report describes the isolation from two cranberry sources and the complete structure elucidation of two arabinoxyloglucan oligosaccharides through the use of carbohydrate-specific NMR spectroscopic and chemical derivatization methods. These compounds were identified as the heptasaccharide ß-d-glucopyranosyl-(1→4)-[α-d-xylopyranosyl-(1→6)]-ß-d-glucopyranosyl-(1→4)-ß-d-glucopyranosyl-(1→4)-[α-l-arabinofuranosyl-(1→2)-α-d-xylopyranosyl-(1→6)]-ß-d-glucopyranose (1) and the octasaccharide ß-d-glucopyranosyl-(1→4)-[α-l-arabinofuranosyl-(1→2)-α-d-xylopyranosyl-(1→6)]-ß-d-glucopyranosyl-(1→4)-ß-d-glucopyranosyl-(1→4)-[α-l-arabinofuranosyl-(1→2)-α-d-xylopyranosyl-(1→6)]-ß-d-glucopyranose (2). Selected fractions and the isolated compounds were subjected to antimicrobial, cell viability, and E. coli antiadhesion assays. Results indicated that enriched fractions and purified compounds lacked antimicrobial and cytotoxic effects, supporting the potential use of such compounds for disease prevention without the risk for resistance development. Preliminary antiadhesion results indicated that mixtures of oligosaccharides exhibited greater antiadhesion properties than purified fractions or pure compounds. The potential use of cranberry oligosaccharides for the prevention of UTIs warrants continued investigations of this complex compound series.


Asunto(s)
Oligosacáridos/química , Vaccinium macrocarpon/química , Conformación de Carbohidratos , Espectroscopía de Resonancia Magnética con Carbono-13/métodos , Espectroscopía de Protones por Resonancia Magnética/métodos
12.
J Nat Prod ; 79(9): 2279-86, 2016 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-27548746

RESUMEN

Continued investigation of the polyphenolic pool of the fruits of Mansoa hirsuta afforded four additional members of the new class of glucosylated oligomeric flavonoids comprising a flavanone core linked to 1,3-diarylpropane C6-C3-C6 units. The structures and absolute configurations of mansoins C-F (3-6) were established by analysis of NMR and electronic circular dichroism data. Mansoin C (3) was identified as a diglucosylated heterodimer, whereas mansoins D (4), E (5), and F (6) were identified as triglucosylated heterotrimers, isomeric with mansoin A (1). Mansoin F (6) inhibited TNF-α release by lipopolysaccharide-stimulated THP-1 cells (IC50 of 19.3 ± 1.3 µM) and, as with mansoin A (1), reduced the phosphorylation levels of p-65-NF-κB, when assayed at 50 µM. These results indicate that the potential anti-inflammatory properties of mansoin F (6) are probably due to inhibition of the NF-κB pathway and inhibition of TNF-α release.


Asunto(s)
Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/farmacología , Bignoniaceae/química , Flavonoides/aislamiento & purificación , Flavonoides/farmacología , Glucósidos/aislamiento & purificación , Glucósidos/farmacología , Antiinflamatorios/química , Flavonoides/química , Frutas/química , Glucósidos/química , Humanos , Lipopolisacáridos/farmacología , Estructura Molecular , FN-kappa B/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
13.
J Nat Prod ; 79(9): 2341-9, 2016 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-27618204

RESUMEN

Two new flavonoids, rac-6-formyl-5,7-dihydroxyflavanone (1) and 2',6'-dihydroxy-4'-methoxy-3'-methylchalcone (2), together with five known derivatives, rac-8-formyl-5,7-dihydroxyflavanone (3), 4',6'-dihydroxy-2'-methoxy-3'-methyldihydrochalcone (4), rac-7-hydroxy-5-methoxy-6-methylflavanone (5), 3'-formyl-2',4',6'-trihydroxy-5'-methyldihydrochalcone (6), and 3'-formyl-2',4',6'-trihydroxydihydrochalcone (7), were isolated from the leaves of Eugenia rigida. The individual (S)- and (R)-enantiomers of 1 and 3, together with the corresponding formylated flavones 8 (6-formyl-5,7-dihydroxyflavone) and 9 (8-formyl-5,7-dihydroxyflavone), as well as 2',4',6'-trihydroxychalcone (10), 3'-formyl-2',4',6'-trihydroxychalcone (11), and the corresponding 3'-formyl-2',4',6'-trihydroxydihydrochalcone (7) and 2',4',6'-trihydroxydihydrochalcone (12), were synthesized. The structures of the isolated and synthetic compounds were established via NMR, HRESIMS, and electronic circular dichroism data. In addition, the structures of 3, 5, and 8 were confirmed by single-crystal X-ray diffraction crystallography. The isolated and synthetic flavonoids were evaluated for their antimicrobial and cytotoxic activities against a panel of microorganisms and solid tumor cell lines.


Asunto(s)
Antineoplásicos Fitogénicos/aislamiento & purificación , Antineoplásicos Fitogénicos/farmacología , Chalconas/aislamiento & purificación , Chalconas/farmacología , Eugenia/química , Flavonoides/aislamiento & purificación , Flavonoides/farmacología , Antineoplásicos Fitogénicos/química , Candida albicans/efectos de los fármacos , Chalconas/química , Cryptococcus neoformans/efectos de los fármacos , Cristalografía por Rayos X , Ensayos de Selección de Medicamentos Antitumorales , Escherichia coli/efectos de los fármacos , Flavanonas , Flavonoides/química , Humanos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Conformación Molecular , Estructura Molecular , Complejo Mycobacterium avium/efectos de los fármacos , Resonancia Magnética Nuclear Biomolecular , Hojas de la Planta/química , Pseudomonas aeruginosa/efectos de los fármacos , Puerto Rico , Staphylococcus aureus/efectos de los fármacos
14.
Mar Drugs ; 13(4): 1632-46, 2015 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-25812034

RESUMEN

Antifungal bioactivity-guided fractionation of the organic extract of the sponge Polymastia boletiformis, collected from the west coast of Ireland, led to the isolation of two new sulfated steroid-amino acid conjugates (1 and 2). Extensive 1D and 2D NMR analyses in combination with quantum mechanical calculations of the electronic circular dichroism (ECD) spectra, optical rotation, and 13C chemical shifts were used to establish the chemical structures of 1 and 2. Both compounds exhibited moderate antifungal activity against Cladosporium cucumerinum, while compound 2 was also active against Candida albicans. Marine natural products containing steroidal and amino acid constituents are extremely rare in nature.


Asunto(s)
Antifúngicos/aislamiento & purificación , Candida albicans/efectos de los fármacos , Colestadienos/aislamiento & purificación , Cladosporium/efectos de los fármacos , Descubrimiento de Drogas , Glicina/análogos & derivados , Poríferos/química , Animales , Antifúngicos/química , Antifúngicos/farmacología , Océano Atlántico , Candida albicans/crecimiento & desarrollo , Colestadienos/química , Colestadienos/farmacología , Cromatografía Líquida de Alta Presión , Dicroismo Circular , Cladosporium/crecimiento & desarrollo , Pruebas Antimicrobianas de Difusión por Disco , Glicina/química , Glicina/aislamiento & purificación , Glicina/farmacología , Irlanda , Espectroscopía de Resonancia Magnética , Metilación , Estructura Molecular , Poríferos/crecimiento & desarrollo , Teoría Cuántica , Espectrometría de Masa por Ionización de Electrospray , Estereoisomerismo , Compuestos de Azufre/química , Compuestos de Azufre/aislamiento & purificación , Compuestos de Azufre/farmacología
15.
J Nat Prod ; 77(4): 824-30, 2014 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-24576254

RESUMEN

Mansoins A (1) and B (2) isolated from the fruits of Mansoa hirsuta represent new glucosylated heterotrimeric flavonoids with a flavanone core linked to two 1,3-diarylpropane C6-C3-C6 units. Their structures and absolute configurations were established by analysis of their NMR and electronic circular dichroism spectroscopic data. Compounds 1 and 2 inhibited TNF-α release by LPS-stimulated THP-1 cells with different potencies, with mansoin B (2) being active at lower concentrations than mansoin A (1) (IC50 values 20.0±1.4 and 48.1±1.8 µM, respectively). These results indicate potential anti-inflammatory properties for this structural type of oligoflavonoids, especially for mansoin B (2).


Asunto(s)
Bignoniaceae/química , Flavonoides/aislamiento & purificación , Flavonoides/farmacología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Antiinflamatorios/farmacología , Brasil , Flavonoides/química , Frutas/química , Humanos , Lipopolisacáridos/farmacología , Estructura Molecular , Óxido Nítrico , Resonancia Magnética Nuclear Biomolecular , Extractos Vegetales/farmacología
16.
J Nat Prod ; 77(5): 1140-9, 2014 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-24761805

RESUMEN

Continued interest in the chemistry of Dalea spp. led to investigation of Dalea searlsiae, a plant native to areas of the western United States. Methanol extractions of D. searlsiae roots and subsequent chromatographic fractionation afforded the new prenylated and geranylated flavanones malheurans A-D (1-4) and known flavanones (5 and 6). Known rotenoids (7 and 8) and isoflavones (9 and 10) were isolated from aerial portions. Structure determination of pure compounds was accomplished primarily by extensive 1D- and 2D-NMR spectroscopy. The absolute configurations of compounds 1-5, 7, and 8 were assigned using electronic circular dichroism spectroscopy. Antimicrobial bioassays revealed significant activity concentrated in the plant roots. Compounds 1-6 exhibited MICs of 2-8 µg/mL against Streptococcus mutans, Bacillus cereus, and oxacillin-sensitive and -resistant Staphylococcus aureus. Aerial metabolites 7-10 were inactive against these organisms, but the presence of 7 and 8 prompted investigation of the antiinsectan activity of D. searlsiae metabolites toward the major crop pest Spodoptera frugiperda (fall armyworm). While compounds 1-10 all caused significant reductions in larval growth rates, associated mortality (33-66%) was highest with flavanone 4 and rotenoids 7 and 8. These findings suggest a differential allocation of antimicrobial and antiinsectan plant resources to root and aerial portions of the plant, respectively.


Asunto(s)
Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/farmacología , Fabaceae/química , Flavanonas/aislamiento & purificación , Flavanonas/farmacología , Fenoles/aislamiento & purificación , Fenoles/farmacología , Animales , Antiinfecciosos/química , Flavanonas/química , Flavonoides/química , Larva/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Oxacilina/farmacología , Fenoles/química , Raíces de Plantas/química , Spodoptera/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/genética
17.
J Nat Prod ; 77(3): 521-6, 2014 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-24479468

RESUMEN

Continuing investigation of fractions from a supercritical fluid extract of Chinese licorice (Glycyrrhiza uralensis) roots has led to the isolation of 12 phenolic compounds, of which seven were described previously from this extract. In addition to these seven metabolites, four known components, 1-methoxyerythrabyssin II (4), 6,8-diprenylgenistein, gancaonin G (5), and isoglycyrol (6), and one new isoflavan, licorisoflavan C (7), were characterized from this material for the first time. Treatment of licoricidin (1) with palladium chloride afforded larger amounts of 7 and also yielded two new isoflavans, licorisoflavan D (8), which was subsequently detected in the licorice extract, and licorisoflavan E (9). Compounds 1-9 were evaluated for their antibacterial activities against the cariogenic Streptococcus mutans and the periodontopathogenic Porphyromonas gingivalis. Licoricidin (1), licorisoflavan A (2), and 7-9 showed antibacterial activity against P. gingivalis (MICs of 1.56-12.5 µg/mL). The most potent activity against S. mutans was obtained with 7 (MIC of 6.25 µg/mL), followed by 1 and 9 (MIC of 12.5 µg/mL). This study provides further evidence for the therapeutic potential of licorice extracts for the treatment and prevention of oral infections.


Asunto(s)
Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Glycyrrhiza uralensis/química , Isoflavonas/aislamiento & purificación , Isoflavonas/farmacología , Porphyromonas gingivalis/efectos de los fármacos , Piranos/aislamiento & purificación , Piranos/farmacología , Streptococcus mutans/efectos de los fármacos , Antibacterianos/química , Benzopiranos/química , Genisteína/análogos & derivados , Genisteína/química , Alemania , Glycyrrhiza/metabolismo , Isoflavonas/química , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Paladio/farmacología , Fenoles/química , Fenoles/aislamiento & purificación , Fenoles/farmacología , Raíces de Plantas/química , Pterocarpanos/química , Pterocarpanos/aislamiento & purificación , Piranos/química
18.
J Nat Prod ; 76(5): 915-25, 2013 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-23631483

RESUMEN

New potential treatments for disseminated fungal infections are needed, especially for infections caused by the commonly drug-resistant pathogens Candida albicans and C. glabrata. These pathogens cause systemic candidiasis, a significant cause of mortality in immune-compromised patients. ABC transporters of the pleiotropic drug resistance subfamily, such as Cdr1p of C. albicans, play an important role in antifungal resistance and are potential bioassay targets for antifungal therapies against drug-resistant pathogens. We observed strong antifungal growth inhibitory activity in the methanol extract of Dalea formosa roots. This extract afforded six new isoflavonoids, sedonans A-F (1-6), a new but-2-enolide, 4'-O-methylpuerol A (7), and the new pterocarpan ent-sandwicensin (8). The structures and absolute configurations of these compounds were assigned using spectroscopic and chiroptical techniques. The direct antifungal activity of 1 against C. glabrata (MIC = 20 µM) was higher than that of fluconazole. Sedonans A-F and ent-sandwicensin were also active against Saccharomyces cerevisiae strains that express differing ABC transporter-associated resistance mechanisms but differed in their susceptibility to Cdr1p-mediated detoxification. A sedonan A (1)/ent-sandwicensin (8) combination exhibited synergistic growth inhibition. The results demonstrate that multiple crude extract compounds are differentially affected by efflux-mediated resistance and are collectively responsible for the observed bioactivity.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/metabolismo , Fabaceae/química , Isoflavonas/aislamiento & purificación , Isoflavonas/farmacología , Antifúngicos/farmacología , Arizona , Candida albicans/efectos de los fármacos , Candida albicans/genética , Candida albicans/metabolismo , Farmacorresistencia Fúngica/efectos de los fármacos , Fluconazol/farmacología , Humanos , Isoflavonas/química , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Raíces de Plantas/química
19.
Biochem Syst Ecol ; 48: 96-99, 2013 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-23459662

RESUMEN

Phytochemical investigation of the leaves of Cecropia schreberiana Miq. (Urticaceae) led to the isolation of four triterpenoids (1-4), three flavone C-glycosides (5-7), two flavan-3-ols (8, 9), two flavanolignans (10, 11), and two proanthocyanidins (12, 13). All compounds were isolated from C. schreberiana for the first time. This is the first report demonstrating the presence of arjunolic acid (4), cinchonain Ia (10), and cinchonain Ib (11) in the Urticaceae family. The occurrence of flavanolignans within the family Urticaceae supports the likelihood that such compounds are more common within the class Magnoliopsida than previously thought.

20.
Neoplasia ; 35: 100851, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36410226

RESUMEN

Diffuse Midline Glioma (DMG) which includes Diffuse Intrinsic Pontine Glioma (DIPG) is an infiltrative tumor of the midline structures of the central nervous system that demonstrates an aggressive pattern of growth and has no known curative treatment. As these tumors progress, children experience ongoing neurological decline including inability to ambulate, swallow and communicate effectively. We propose that optimal care for patients with DMG should involve a specialized team experienced in caring for the multifaceted needs of these patients and their families. Herein we review the roles and evidence to support early involvement of a specialized interdisciplinary team and outline our views on best practices for these challenging tumors.


Asunto(s)
Neoplasias del Tronco Encefálico , Glioma , Humanos , Niño , Neoplasias del Tronco Encefálico/diagnóstico , Neoplasias del Tronco Encefálico/terapia , Neoplasias del Tronco Encefálico/patología , Glioma/diagnóstico , Glioma/genética , Glioma/terapia
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