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1.
Spec Care Dentist ; 41(3): 319-326, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33576541

RESUMEN

OBJECTIVES: This observational study aims to determine individual dental doses in oropharyngeal cancer (OPC) patients managed by intensity modulated radiation treatment (IMRT). MATERIALS AND METHODS: OPC patients treated with IMRT had each tooth individually contoured on post-IMRT CT scans. The mean, maximum and minimum doses were calculated per tooth-based upon patient and tumor demographics (tumor size and nodal status). RESULTS: A total of 160 patients were included in this study. Escalating tumor size and nodal status led to an observed increase in Dmean doses to the dentition on the contralateral tumor side. A significant region in both jaws received >30 Gy in this tumor group. CONCLUSION: Tumor demographics were observed to influence RT doses to the dentition and need to be considered when providing a pre-RT dental assessment. The observed dose of >30 Gy in large spans of the dentition and jaws highlights future risk of dental deterioration and ORN with long term survival.


Asunto(s)
Neoplasias Orofaríngeas , Radioterapia de Intensidad Modulada , Humanos , Neoplasias Orofaríngeas/radioterapia , Dosis de Radiación , Dosificación Radioterapéutica , Tomografía Computarizada por Rayos X
2.
Am J Clin Oncol ; 44(6): 239-246, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33867481

RESUMEN

OBJECTIVE: Preclinical studies with muscadine grape extract (MGE) show antitumor activity and decreased systemic inflammation. This phase I study (NCT02583269) assessed safety and tolerability of a proprietary MGE preparation in patients with advanced solid tumors. METHODS: Patients with metastatic or unresectable cancers who were progressing on standard therapies were assigned to MGE in a standard 3+3 design. Five dose levels were tested (320 to 1600 mg total phenolics/d). Safety and maximum-tolerated dose were assessed after 4 weeks. Patients were evaluated for response at 8 weeks and continued on MGE if clinically stable. Secondary outcomes were response, survival, adherence, fatigue, and quality of life (QOL). RESULTS: In total, 23 patients (lung, n=7; gastrointestinal, n=7; genitourinary, n=6; other, n=3) received MGE capsules by mouth twice daily. The cohort [median age 72 years, 48% Eastern Cooperative Oncology Group (ECOG) 2] was heavily pretreated. After 4 weeks on MGE, possibly attributable adverse events grade 2 or higher were fatigue (n=1), decreased lymphocyte count (n=1), and constipation (n=2), including 1 dose-limiting toxicity for grade 3 constipation. Maximum-tolerated dose was not reached. No partial responses were observed. Median time on therapy was 8 weeks, with 29% of patients treated beyond 16 weeks and a median overall survival of 7.2 months. QOL and fatigue levels were stable from baseline to 8 weeks. Higher MGE dose was correlated with improvement in self-reported physical well-being QOL at 8 weeks (r=0.6; P=0.04). CONCLUSIONS: MGE is safe and well-tolerated in heavily pretreated and older cancer patients.  The potential anticancer properties and the effects of MGE on physical well-being and QOL metrics will be evaluated in future studies.


Asunto(s)
Neoplasias/tratamiento farmacológico , Extractos Vegetales/farmacocinética , Extractos Vegetales/uso terapéutico , Vitis/química , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Metástasis de la Neoplasia , Neoplasias/patología , Pronóstico , Distribución Tisular
3.
PLoS One ; 15(10): e0240189, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33031441

RESUMEN

Tissue factor (TF) is critical for the activation of blood coagulation. TF function is regulated by the amount of externalised phosphatidylserine (PS) and phosphatidylethanolamine (PE) on the surface of the cell in which it is expressed. We investigated the role PS and PE in fibroblast TF function. Fibroblasts expressed 6-9 x 104 TF molecules/cell but had low specific activity for FXa generation. We confirmed that this was associated with minimal externalized PS and PE and characterised for the first time the molecular species of PS/PE demonstrating that these differed from those found in platelets. Mechanical damage of fibroblasts, used to simulate vascular injury, increased externalized PS/PE and led to a 7-fold increase in FXa generation that was inhibited by annexin V and an anti-TF antibody. Platelet-derived extracellular vesicles (EVs), that did not express TF, supported minimal FVIIa-dependent FXa generation but substantially increased fibroblast TF activity. This enhancement in fibroblast TF activity could also be achieved using synthetic liposomes comprising 10% PS without TF. In conclusion, despite high levels of surface TF expression, healthy fibroblasts express low levels of external-facing PS and PE limiting their ability to generate FXa. Addition of platelet-derived TF-negative EVs or artificial liposomes enhanced fibroblast TF activity in a PS dependent manner. These findings contribute information about the mechanisms that control TF function in the fibroblast membrane.


Asunto(s)
Vesículas Extracelulares/metabolismo , Fibroblastos/metabolismo , Tromboplastina/metabolismo , Coagulación Sanguínea , Plaquetas/metabolismo , Línea Celular , Humanos , Liposomas/metabolismo , Fosfatidiletanolaminas/metabolismo , Fosfatidilserinas/metabolismo , Tromboplastina/genética
4.
mBio ; 9(6)2018 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-30538187

RESUMEN

Over 80% of travelers from the United Kingdom to the Indian subcontinent acquire CTX-M-producing Escherichia coli (CTX-M-EC), but the mechanism of CTX-M-EC acquisition is poorly understood. We aimed to investigate the dynamics of CTX-M-EC acquisition in healthy travelers and how this relates to populations of non-CTX-M-EC in the fecal microbiome. This is a prospective observational study of healthy volunteers traveling from the United Kingdom to South Asia. Fecal samples were collected pre- and post-travel at several time points up to 12 months post-travel. A toothpicking experiment was used to determine the proportion of cephalosporin-sensitive E. coli in fecal samples containing CTX-M-EC. MLST and SNP type of pre-travel and post-travel E. coli were deduced by WGS. CTX-M-EC was acquired by 89% (16/18) of volunteers. Polyclonal acquisition of CTX-M-EC was seen in 8/15 volunteers (all had >3 STs across post-travel samples), suggesting multiple acquisition events. Indistinguishable CTX-M-EC clones (zero SNPs apart) are detectable in serial fecal samples up to 7 months after travel, indicating stable maintenance in the fecal microbiome on return to the United Kingdom in the absence of selective pressure. CTX-M-EC-containing samples were often co-colonized with novel, non-CTX-M strains after travel, indicating that acquisition of non-CTX-M-EC occurs alongside CTX-M-EC. The same pre-travel non-CTX-M strains (<10 SNPs apart) were found in post-travel fecal samples after CTX-M-EC had been lost, suggesting return of the fecal microbiome to the pre-travel state and long-term persistence of minority strains in travelers who acquire CTX-M-EC.IMPORTANCEEscherichia coli strains which produce CTX-M extended-spectrum beta-lactamases are endemic as colonizers of humans and in the environment in South Asia. This study demonstrates that acquisition of CTX-M-producing E. coli (CTX-M-EC) in travelers from the United Kingdom to South Asia is polyclonal, which is likely due to multiple acquisition events from contaminated food and drinking water during travel. CTX-M-EC frequently persists in the fecal microbiome for at least 1 year after acquisition, often alongside newly acquired non-CTX-M E. coli strains. In travelers who acquire CTX-M-EC, pre-travel non-CTX-M E. coli remains as a minority population in the gut until the CTX-M-EC strains are lost. The non-CTX-M strains are then reestablished as the predominant E. coli population. This study has shed light on the dynamics of CTX-M-EC acquisition, colonization, and loss after travel. Future work involving manipulation of nonvirulent resident E. coli could be used to prevent colonization with antibiotic-resistant E. coli.


Asunto(s)
Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/análisis , Escherichia coli/aislamiento & purificación , Heces/microbiología , Enfermedad Relacionada con los Viajes , beta-Lactamasas/análisis , Adulto , Asia , Escherichia coli/enzimología , Microbioma Gastrointestinal , Genotipo , Voluntarios Sanos , Humanos , Pruebas de Sensibilidad Microbiana , Microbiota , Tipificación de Secuencias Multilocus , Polimorfismo de Nucleótido Simple , Estudios Prospectivos , Reino Unido , Secuenciación Completa del Genoma
5.
J Pharm Pharmacol ; 58(7): 903-8, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16805949

RESUMEN

This work explored the use of pluronic lecithin organogel (PLO) as a base for the delivery of bioactive polyunsaturated fatty acids from fish oil, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and ketoprofen. PLO was adapted to contain fish oil, ketoprofen, or both, and 1,8-cineole as penetration enhancer, and used to determine the in-vitro permeation from infinite and finite dosing protocols across full thickness porcine skin. Oruvail gel (2.5% ketoprofen) was included for comparison. No EPA or DHA was found to permeate skin when applied as an infinite dose. From multiple finite doses, small amount (max. 0.22%) of fish oil were found to permeate the skin. This indicates retention of fish oil within the gel matrix and that the viable domain of full thickness skin was a significant barrier. Greater amounts of EPA and DHA were delivered in the presence of ketoprofen indicating co-transport resulting from selective complexation, although no enhancement was observed using 1,8-cineole. Unlike EPA and DHA, substantial amounts of ketoprofen permeated when applied as infinite doses. Oruvail, a Carbopol 940-based hydrogel containing 2.5% ketoprofen and ethanol, delivered the greatest amount, although similar to the PLO gel containing 5% ketoprofen. The addition of propylene glycol enhanced permeation, although the presence of fish oil in the PLO gel inhibited ketoprofen permeation. When applied as multiple finite doses a maximum of 76 microm cm(-2) (1.12%) was delivered, which was reduced by the presence of 1,8-cineole. Greater permeation was again observed with Oruvail by a factor of two and with half the ketoprofen dose. To conclude, a PLO-based gel is capable of delivering EPA and DHA via a repeat finite dosing regimen, although there is evidence for the retention of these very lipophilic molecules within the gel matrix. Although to a lesser extent than EPA and DHA, ketoprofen was also substantially retained, as exemplified by the superior delivery rates from Oruvail. Finally, this work has highlighted the importance of using an appropriate topical dosing method to match the intended use of a product.


Asunto(s)
Sistemas de Liberación de Medicamentos , Ácidos Grasos Insaturados/administración & dosificación , Aceites de Pescado/química , Cetoprofeno/administración & dosificación , Fosfatidilcolinas/química , Poloxámero/química , Administración Cutánea , Animales , Cromatografía Líquida de Alta Presión , Ácidos Grasos Insaturados/química , Ácidos Grasos Insaturados/farmacocinética , Geles , Técnicas In Vitro , Cetoprofeno/química , Cetoprofeno/farmacocinética , Piel/metabolismo , Absorción Cutánea , Porcinos
6.
Artículo en Inglés | MEDLINE | ID: mdl-27039003

RESUMEN

OBJECTIVES: To analyze clinical features, dosimetric parameters, and outcomes of osteoradionecrosis (ORN). STUDY DESIGN: Thirty-six patients with ORN who had been previously treated with radiotherapy (RT) were retrospectively identified between January 2009 and April 2014. ORN volumes were contoured on planning computed tomography (CT) scans. Near maximum dose (D2%), minimum dose (Dmin), mean dose (Dmean), and percentage of bone volume receiving 50 Gy (V50) were examined. Clinical and dosimetric variables were considered to compare ORN resolution versus ORN persistence. RESULTS: Median interval time from end of RT to development of ORN was 6 months. Of the ORN cases, 61% were located in the mandible. Dmean to affected bone was 57.6 Gy, and 44% had a D2% 65 Gy or greater. Smoking was associated with ORN persistence on univariate analysis, but no factors were found to impact ORN resolution or progression on logistic regression. CONCLUSIONS: Prevention strategies for ORN development should be prioritized. Dose-volume parameters could have a role in preventing ORN.


Asunto(s)
Neoplasias de Cabeza y Cuello/radioterapia , Osteorradionecrosis/diagnóstico por imagen , Osteorradionecrosis/etiología , Adulto , Anciano , Anciano de 80 o más Años , Quimioterapia Adyuvante , Femenino , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Dimensión del Dolor , Radiometría , Dosificación Radioterapéutica , Estudios Retrospectivos , Factores de Riesgo
7.
PLoS One ; 10(8): e0134964, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26252208

RESUMEN

Abundant evidence exists to support a role for lignin as an important element in biomass recalcitrance. However, several independent studies have also shown that factors apart from lignin are also relevant and overall, the relative importance of different recalcitrance traits remains in dispute. In this study we used two genetically distant sugarcane genotypes, and performed a correlational study with the variation in anatomical parameters, cell wall composition, and recalcitrance factors between these genotypes. In addition we also tracked alterations in these characteristics in internodes at different stages of development. Significant differences in the development of the culm between the genotypes were associated with clear differential distributions of lignin content and composition that were not correlated with saccharification and fermentation yield. Given the strong influence of the environment on lignin content and composition, we hypothesized that sampling within a single plant could allow us to more easily interpret recalcitrance and changes in lignin biosynthesis than analysing variations between different genotypes with extensive changes in plant morphology and culm anatomy. The syringyl/guaiacyl (S/G) ratio was higher in the oldest internode of the modern genotype, but S/G ratio was not correlated with enzymatic hydrolysis yield nor fermentation efficiency. Curiously we observed a strong positive correlation between ferulate ester level and cellulose conversion efficiency. Together, these data support the hypothesis that biomass enzymatic hydrolysis recalcitrance is governed by a quantitative heritage rather than a single trait.


Asunto(s)
Biotecnología/métodos , Celulosa/metabolismo , Etanol/metabolismo , Hibridación Genética , Saccharum/genética , Metabolismo de los Hidratos de Carbono , Pared Celular/metabolismo , Esterificación , Fermentación , Genotipo , Hidrólisis , Lignina/metabolismo , Espectroscopía de Resonancia Magnética , Tallos de la Planta/crecimiento & desarrollo , Saccharum/anatomía & histología , Saccharum/crecimiento & desarrollo , Ácidos Urónicos/metabolismo , Xilanos/metabolismo
8.
J Anal Toxicol ; 38(6): 315-21, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24812645

RESUMEN

Availability and consumption of synthetic cannabinoids have risen recently in the USA and Europe. These drugs have adverse effects, including acute psychosis and bizarre behavior. In 2012, the United States Drug Enforcement Agency permanently banned five of the synthetic cannabinoids and in 2013, temporarily added XLR11, UR-144 and AKB48 to Schedule I of the Controlled Substances Act. As synthetic cannabinoid strains are added to the Schedule I list, new strains are being introduced into the market. XLR11 and UR-144 are two of the most recent additions to the synthetic cannabinoid drug class. To test collected oral fluid samples for XLR11 and UR-144, we developed a bioanalytical method that initially purifies the sample with solid-phase extraction and then quantitatively identifies the drugs with ultra-high-performance liquid chromatography-tandem mass spectrometry. The method was validated according to United States Food and Drug Administration guidelines and Scientific Working Group for Forensic Toxicology guidelines and the validation data showed that the method is an accurate, precise, robust and efficient method suited for high-throughput toxicological screening applications. We tested human subject samples with the developed method and found the presence of parent drugs (XLR11 and UR-144), their metabolites and their pyrolysis products in oral fluid.


Asunto(s)
Líquidos Corporales/química , Cannabinoides/análisis , Indoles/análisis , Detección de Abuso de Sustancias/métodos , Cannabinoides/farmacocinética , Cromatografía Líquida de Alta Presión , Calor , Humanos , Indoles/farmacocinética , Límite de Detección , Boca/química , Reproducibilidad de los Resultados , Saliva/química , Extracción en Fase Sólida , Detección de Abuso de Sustancias/instrumentación , Espectrometría de Masas en Tándem
9.
J Gastrointest Cancer ; 45(3): 268-75, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24452995

RESUMEN

PURPOSE: This phase II single-institution trial of adjuvant thalidomide after cytoreductive surgery (CS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for patients with appendiceal and colorectal malignancies sought to detect an improvement in progression-free survival (PFS) from 7 to 12 months. METHODS: Eligible patients received CS, HIPEC, and baseline imaging, followed by pretreatment thalidomide counseling. All participants were then started on a 28-day regimen of thalidomide, 100 mg by mouth at bedtime, followed by 200 mg for 4 weeks, followed by 300 mg as the final maintenance dose, as tolerated. RESULTS: Twenty-seven eligible patients (median age 52 years; 52% appendiceal/48% colorectal) were enrolled on this trial and included in the analysis, and 26 were evaluable for response. Eighteen patients demonstrated stable disease on adjuvant thalidomide, while eight showed evidence of progression. Approximately 30% of the patients withdrew due to toxicity. Grade 3/4 toxicities included neurological disorders (16%), nausea (12%), vomiting (8%), and thromboembolism (8%). Median overall survival (OS) and PFS were 43.0 and 9.3 months, respectively, and median follow-up was 40.4 months. Multivariate modeling showed significant improvements in PFS and OS for appendiceal patients and those with R0 or R1 resections. On an intent-to-treat analysis, the PFS of the study group was 9 months. CONCLUSIONS: Based on these findings, thalidomide cannot be recommended as adjuvant therapy after CS and HIPEC for gastrointestinal malignancies. Further research is needed to identify active agents in this population.


Asunto(s)
Adenocarcinoma/secundario , Inhibidores de la Angiogénesis/uso terapéutico , Antineoplásicos/uso terapéutico , Neoplasias del Apéndice/patología , Quimioterapia Adyuvante/métodos , Neoplasias Colorrectales/patología , Hipertermia Inducida , Neoplasias Peritoneales/secundario , Talidomida/uso terapéutico , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/cirugía , Adenocarcinoma/terapia , Adulto , Anciano , Inhibidores de la Angiogénesis/administración & dosificación , Inhibidores de la Angiogénesis/efectos adversos , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Neoplasias del Apéndice/cirugía , Neoplasias Colorrectales/cirugía , Terapia Combinada , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Infusiones Parenterales , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Náusea/inducido químicamente , Enfermedades del Sistema Nervioso/inducido químicamente , Neoplasias Peritoneales/tratamiento farmacológico , Neoplasias Peritoneales/cirugía , Neoplasias Peritoneales/terapia , Talidomida/administración & dosificación , Talidomida/efectos adversos , Tromboembolia/inducido químicamente , Resultado del Tratamiento , Vómitos/inducido químicamente
10.
Methods Mol Biol ; 790: 191-200, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21948416

RESUMEN

In recent years, the majority of research on surface patterning, as a means of precisely controlling cell -positioning and adhesion on surfaces, has focused on eukaryotic cells. Such research has led to new insights into cell biology, advances in tissue engineering, and cell motility. In contrast, considerably less work has been reported on tightly controlled patterning of bacteria, despite its potential in a wide variety of applications, including fabrication of in vitro model systems for studies of bacterial processes, such as quorum sensing and horizontal gene transfer. This is partly due to their small size - often 1-3 µm or less. To study these processes, microscale and nanoscale engineered material surfaces must be developed to create in vitro bacteria arrays, which can allow valuable insights into natural systems such as the soil or the human gut, and are often complex and spatially structured habitats. Here, we outline a protocol to create defined patterns of bacteria to study such systems at the single cell level that is based on the formation of protein nanoarrays on mannoside-terminated self-assembled monolayers via nanocontact printing and the subsequent deposition of bacteria from solution on the unpatterned regions of the mannoside-terminated substrate.


Asunto(s)
Técnicas de Cultivo/instrumentación , Escherichia coli/citología , Oro/química , Nanotecnología/instrumentación , Análisis por Matrices de Proteínas/instrumentación , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Comunicación Celular , Células Inmovilizadas/citología , Dimetilpolisiloxanos/química , Lectina de Unión a Manosa/química , Lectina de Unión a Manosa/metabolismo , Manósidos/química , Manósidos/metabolismo , Impresión , Propiedades de Superficie
11.
Cardiovasc Intervent Radiol ; 30(6): 1192-200, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17828426

RESUMEN

Experimental and clinical data suggest that stents eluting antiproliferative agents can be used for the prevention of in-stent restenosis. Here we investigate in vitro the antiproliferative and apoptotic effect of D-24851 and evaluate the safety and efficacy of D-24851-eluting polymer-coated stents in a rabbit restenosis model (n = 53). Uncoated stents (n = 6), poly (DL: -lactide-co-glycolide) (PLGA)-coated stents (n = 7), and PLGA-coated stents loaded with 0.08 +/- 0.0025 microM (31 +/- 1 mug; low dose; n = 7), 0.55 +/- 0.02 microM (216 +/- 8 mug; high dose; n = 6), and 4.55 +/- 0.1 microM (1774 +/- 39 mug; extreme dose; n = 5) of D-24851 were randomly implanted in New Zealand rabbit right iliac arteries and the animals were sacrificed after 28 days for histomorphometric analysis. For the assessment of endothelial regrowth in 90 days, 12 rabbits were subjected to PLGA-coated (n = 3), low-dose (n = 3), high-dose (n = 3), and extreme-dose (n = 3) stent implantation. In vitro studies revealed that D-24851 exerts its growth inhibitory effects via inhibition of proliferation and induction of apoptosis without increasing the expression of heat shock protein-70, a cytoprotective and antiapoptotic protein. Treatment with low-dose D-24851 stents was associated with a significant reduction in neointimal area and percentage stenosis only compared with bare metal stents (38% [P = 0.029] and 35% [P = 0.003] reduction, respectively). Suboptimal healing, however, was observed in all groups of D-24851-loaded stents in 90 days in comparison with PLGA-coated stents. We conclude that low-dose D-24851-eluting polymer-coated stents significantly inhibit neointimal hyperplasia at 28 days through inhibition of proliferation and enhancement of apoptosis. In view of the suboptimal re-endothelialization, longer-term studies are needed in order to establish whether the inhibition of intimal growth is maintained.


Asunto(s)
Acetamidas/farmacología , Implantación de Prótesis Vascular , Oclusión de Injerto Vascular/prevención & control , Arteria Ilíaca/cirugía , Indoles/farmacología , Stents , Túnica Íntima/efectos de los fármacos , Análisis de Varianza , Animales , Apoptosis , Western Blotting , Cateterismo/instrumentación , Materiales Biocompatibles Revestidos , Hiperplasia , Masculino , Microscopía Electrónica de Rastreo , Microscopía Fluorescente , Modelos Animales , Polímeros , Diseño de Prótesis , Conejos , Distribución Aleatoria , Acero Inoxidable , Túnica Íntima/patología
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