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1.
medRxiv ; 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38712133

RESUMEN

Here we report the results of a single-center phase 2 clinical trial combining sorafenib tosylate, valproic acid, and sildenafil for the treatment of patients with recurrent high-grade glioma (NCT01817751). Clinical toxicities were grade 1 and grade 2, with one grade 3 toxicity for maculopapular rash (6.4%). For all evaluable patients, the median progression-free survival was 3.65 months and overall survival (OS) 10.0 months. There was promising evidence showing clinical activity and benefit. In the 33 evaluable patients, low protein levels of the chaperone GRP78 (HSPA5) was significantly associated with a better OS (p < 0.0026). A correlation between the expression of PDGFRα and OS approached significance (p < 0.0728). Five patients presently have a mean OS of 73.6 months and remain alive. This is the first therapeutic intervention glioblastoma trial to significantly associate GRP78 expression to OS. Our data suggest that the combination of sorafenib tosylate, valproic acid, and sildenafil requires additional clinical development in the recurrent glioma population.

2.
Anticancer Drugs ; 35(5): 450-458, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38452059

RESUMEN

The purpose of this study is to establish the recommended phase 2 dose for regorafenib in combination with sildenafil for patients with advanced solid tumors. Secondary outcomes included identification of antitumor effects of regorafenib and sildenafil, toxicity of the combination, determination of PDE5 expression in tumor samples, and the impact of sildenafil on the pharmacokinetics of regorafenib. This study was a phase 1, open-label single-arm dose-escalation trial using a 3 + 3 design. Additional patients were enrolled at the maximum tolerated dose (MTD) until a total of 12 patients were treated at the MTD. A total of 29 patients were treated in this study. The median duration of treatment was 8 weeks. The recommended phase 2 doses determined in this study are regorafenib 160 mg daily with sildenafil 100 mg daily. The most common toxicities included palmar-plantar erythrodysesthesia syndrome (20 patients, 69%) and hypophosphatemia (18 patients, 62%). Two patients (7%) experienced grade 4 lipase increase. Objective responses were not observed; however, 14 patients (48%) had a period of stable disease during the study. Stable disease for up to 12 months was observed in patients with ovarian cancer as well as up to 20 months for a patient with cervical cancer. The combination of regorafenib and sildenafil at the recommended phase 2 dose is safe and generally well tolerated. Disease control in patients with gynecologic malignancies was especially encouraging. Further evaluation of the combination of regorafenib and sildenafil in gynecologic malignancies is warranted. Clinical Trial Registration Number: NCT02466802.


Asunto(s)
Neoplasias de los Genitales Femeninos , Neoplasias , Adulto , Femenino , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de los Genitales Femeninos/inducido químicamente , Neoplasias de los Genitales Femeninos/tratamiento farmacológico , Dosis Máxima Tolerada , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Compuestos de Fenilurea/efectos adversos , Piridinas/uso terapéutico , Citrato de Sildenafil/efectos adversos
3.
Nat Commun ; 15(1): 179, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38167814

RESUMEN

Allopatric speciation has been difficult to examine among microorganisms, with prior reports of endemism restricted to sub-genus level taxa. Previous microbial community analysis via 16S rRNA gene sequencing of 925 geothermal springs from the Taupo Volcanic Zone (TVZ), Aotearoa-New Zealand, revealed widespread distribution and abundance of a single bacterial genus across 686 of these ecosystems (pH 1.2-9.6 and 17.4-99.8 °C). Here, we present evidence to suggest that this genus, Venenivibrio (phylum Aquificota), is endemic to Aotearoa-New Zealand. A specific environmental niche that increases habitat isolation was identified, with maximal read abundance of Venenivibrio occurring at pH 4-6, 50-70 °C, and low oxidation-reduction potentials. This was further highlighted by genomic and culture-based analyses of the only characterised species for the genus, Venenivibrio stagnispumantis CP.B2T, which confirmed a chemolithoautotrophic metabolism dependent on hydrogen oxidation. While similarity between Venenivibrio populations illustrated that dispersal is not limited across the TVZ, extensive amplicon, metagenomic, and phylogenomic analyses of global microbial communities from DNA sequence databases indicates Venenivibrio is geographically restricted to the Aotearoa-New Zealand archipelago. We conclude that geographic isolation, complemented by physicochemical constraints, has resulted in the establishment of an endemic bacterial genus.


Asunto(s)
Microbiota , Nueva Zelanda , ARN Ribosómico 16S/genética , Filogenia , Metagenoma
4.
Cancer Chemother Pharmacol ; 91(3): 281-290, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36864346

RESUMEN

PURPOSE: Belinostat is an intravenous histone deacetylase inhibitor with approval for T-cell lymphomas. Adavosertib is a first in class oral Wee1 inhibitor. Preclinical studies of the combination demonstrated synergy in various human acute myeloid leukemia (AML) lines as well as AML xenograft mouse models. EXPERIMENTAL DESIGN: This was a phase 1 dose-escalation study of belinostat and adavosertib in patients with relapsed/refractory AML and myelodysplastic syndrome (MDS). Patients received both drugs on days 1-5 and 8-12 of a 21-day cycle. Safety and toxicity were monitored throughout the study. Plasma levels of both drugs were measured for pharmacokinetic analysis. Response was determined by standard criteria including bone marrow biopsy. RESULTS: Twenty patients were enrolled and treated at 4 dose levels. A grade 4 cytokine release syndrome at dose level 4 (adavosertib 225 mg/day; belinostat 1000 mg/m2) qualified as a dose-limiting toxicity event. The most common non-hematologic treatment-related adverse events were nausea, vomiting, diarrhea, dysgeusia, and fatigue. No responses were seen. The study was terminated prior to maximum tolerated dose/recommended phase 2 dose determination. CONCLUSIONS: The combination of belinostat and adavosertib at the tested dose levels was feasible but without efficacy signals in the relapsed/refractory MDS/AML population.


Asunto(s)
Ácidos Hidroxámicos , Leucemia Mieloide Aguda , Humanos , Animales , Ratones , Ácidos Hidroxámicos/efectos adversos , Pirimidinonas/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/patología
5.
Dev Dyn ; 251(11): 1880-1896, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35809036

RESUMEN

BACKGROUND: Limb buds develop as bilateral outgrowths of the lateral plate mesoderm and are patterned along three axes. Current models of proximal to distal patterning of early amniote limb buds suggest that two signals, a distal organizing signal from the apical epithelial ridge (AER, Fgfs) and an opposing proximal (retinoic acid [RA]) act early on pattern this axis. RESULTS: Transcriptional analysis of stage 51 Xenopus laevis hindlimb buds sectioned along the proximal-distal axis showed that the distal region is distinct from the rest of the limb. Expression of capn8.3, a novel calpain, was located in cells immediately flanking the AER. The Wnt antagonist Dkk1 was AER-specific in Xenopus limbs. Two transcription factors, sall1 and zic5, were expressed in distal mesenchyme. Zic5 has no described association with limb development. We also describe expression of two proximal genes, gata5 and tnn, not previously associated with limb development. Differentially expressed genes were associated with Fgf, Wnt, and RA signaling as well as differential cell adhesion and proliferation. CONCLUSIONS: We identify new candidate genes for early proximodistal limb patterning. Our analysis of RA-regulated genes supports a role for transient RA gradients in early limb bud in proximal-to-distal patterning in this anamniote model organism.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , Esbozos de los Miembros , Animales , Esbozos de los Miembros/metabolismo , Xenopus laevis/genética , Xenopus laevis/metabolismo , Mesodermo/metabolismo , Factores de Crecimiento de Fibroblastos/genética , Factores de Crecimiento de Fibroblastos/metabolismo , Tretinoina/metabolismo , Extremidades , Expresión Génica , Ectodermo/metabolismo , Proteínas de Unión al ADN/genética , Proteínas del Tejido Nervioso/genética , Proteínas de Xenopus/genética , Proteínas de Xenopus/metabolismo
6.
Int J Med Microbiol ; 312(2): 151549, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35114582

RESUMEN

BACKGROUND: Advances in genome sequencing have enabled detailed microbiome analysis; however, the ideal specimen type for sequencing is yet to be determined. Rectal swabs may offer a rapid and convenient modality for colonic microbiome analysis. The aim of this study is to evaluate the use of rectal swabs compared to faecal specimens. METHODS AND RESULTS: Twenty health professionals participated in this study and provided a faecal specimen, a self-collected rectal swab and a rectal swab taken by a clinician. DNA was extracted and 16S rRNA gene sequencing was carried out for microbiome analysis. Alpha diversity was higher in swabs compared to faecal specimens; however, the difference was only significant when comparing clinician-obtained swabs to faeces. Analysis of beta diversity consistently showed that few taxa were affected by sample type. We found sample type accounted for only 6.8% of community variation (R2 = 0.067, p < 0.001, permanova). Notably, there were only six genera identified in clinician-obtained swabs that were not also found in the self-taken swabs. CONCLUSIONS: Both self-collected and clinician obtained rectal swabs are a reliable method of analysing the colonic microbiome. Obtaining specimens for microbiome analysis is often time-critical due to therapy, such as antibiotics, influencing the microbiome. Rectal swabs are shown to be a valid and convenient modality for microbiome analysis.


Asunto(s)
Microbiota , Manejo de Especímenes , Colon , Heces , ARN Ribosómico 16S/genética , Manejo de Especímenes/métodos
7.
Wound Repair Regen ; 30(6): 636-651, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35212086

RESUMEN

Xenopus laevis tadpoles can regenerate functional tails, containing the spinal cord, notochord, muscle, fin, blood vessels and nerves, except for a brief refractory period at around 1 week of age. At this stage, amputation of the tadpole's tail may either result in scarless wound healing or the activation of a regeneration programme, which replaces the lost tissues. We recently demonstrated a link between bacterial lipopolysaccharides and successful tail regeneration in refractory stage tadpoles and proposed that this could result from lipopolysaccharides binding to Toll-like receptor 4 (TLR4). Here, we have used 16S rRNA sequencing to show that the tadpole skin microbiome is highly variable between sibships and that the community can be altered by raising embryos in the antibiotic gentamicin. Six Gram-negative genera, including Delftia and Chryseobacterium, were over-represented in tadpoles that underwent tail regeneration. Lipopolysaccharides purified from a commensal Chryseobacterium spp. XDS4, an exogenous Delftia spp. or Escherichia coli, could significantly increase the number of antibiotic-raised tadpoles that attempted regeneration. Conversely, the quality of regeneration was impaired in native-raised tadpoles exposed to the antagonistic lipopolysaccharide of Rhodobacter sphaeroides. Editing TLR4 using CRISPR/Cas9 also reduced regeneration quality, but not quantity, at the level of the cohort. However, we found that the editing level of individual tadpoles was a poor predictor of regenerative outcome. In conclusion, our results suggest that variable regeneration in refractory stage tadpoles depends at least in part on the skin microbiome and lipopolysaccharide signalling, but that signalling via TLR4 cannot account for all of this effect.


Asunto(s)
Lipopolisacáridos , Microbiota , Animales , Antibacterianos , Larva/fisiología , Lipopolisacáridos/farmacología , ARN Ribosómico 16S , Receptor Toll-Like 4/metabolismo , Cicatrización de Heridas , Xenopus laevis/genética , Xenopus laevis/metabolismo
8.
J Health Psychol ; 26(6): 880-891, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-31144526

RESUMEN

This study explores the experiences and perceptions of recovery in elderly patients who had sustained a proximal humerus fracture. In-depth semi-structured interviews were conducted with 15 patients over the age of 65. Thematic analysis identified aspects of care that impacted upon patient experience and quality of life. Seven main patient-reported themes were identified, including pain, sleep, shoulder function, emotional state, social support, relationship with their professional and experience of healthcare institution. These themes offer insight into the experiences of adults receiving care for proximal humerus fracture and highlight that existing quantitative measures of quality of life do not measure domains that are important to patients.


Asunto(s)
Calidad de Vida , Fracturas del Hombro , Adulto , Anciano , Humanos , Húmero , Dolor , Investigación Cualitativa
9.
Hand Clin ; 36(2): 171-180, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32307047

RESUMEN

The United Kingdom's health care is provided free at the point of delivery by the National Health Service (NHS). The NHS uses an internal market model to fund health care, as opposed to using a provider-purchaser partnership model. Hand surgery is provided by plastic surgeons and trauma and orthopaedic surgeons. The nationalized system has disadvantages and benefits. This environment is heavily cost controlled, with some restrictions on individual practice and associated long waiting times. The advantages include a large population base for research in hand surgery and careful monitoring systems for problems with devices and recommendations for various treatments.


Asunto(s)
Traumatismos de la Mano/cirugía , Mano/cirugía , Ortopedia , Aprobación de Recursos/legislación & jurisprudencia , Educación de Postgrado en Medicina , Regulación Gubernamental , Humanos , Ortopedia/educación , Ortopedia/organización & administración , Apoyo a la Investigación como Asunto , Medicina Estatal , Reino Unido
10.
Magn Reson Chem ; 58(2): 198-203, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31692051

RESUMEN

The exquisitely cytotoxic macrolides, satratoxins G and H, have been reisolated from a solvent extract of a rice culture inoculated with Stachybotrys chartarum to be used as high-purity reference compounds for analytical analyses. Extensive chromatographic separation realized the compounds that were fully recharacterized in two solvents by 1D- and 2D-NMR spectroscopy, revealing some discrepancies in the nuclear magnetic resonance (NMR) data as compared with the previously reported values found in the literature. Detailed spectra are provided in order to aid future identification and dereplication.


Asunto(s)
Espectroscopía de Resonancia Magnética con Carbono-13/métodos , Espectroscopía de Protones por Resonancia Magnética/métodos , Tricotecenos/química , Oryza/microbiología , Stachybotrys/metabolismo
11.
Am J Med Qual ; 28(4): 308-14, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23322909

RESUMEN

Accurate patient identification is a National Patient Safety Goal. Misidentification of surgical specimens is associated with increased morbidity, mortality, and costs of care. The authors developed 12 practical, process-based, standardized measures of surgical specimen identification defects during the preanalytic phase of pathology testing (from the operating room to the surgical pathology laboratory) that could be used to quantify the occurrence of these defects. The measures (6 container and 6 requisition identification defects) were developed by a panel of physicians, pathologists, nurses, and quality experts. A total of 69 hospitals prospectively collected data over 3 months. Overall, there were identification defects in 2.9% of cases (1780/60 501; 95% confidence interval [CI] = 2.0%-4.4%), 1.2% of containers (1018/81 656; 95% CI = 0.8%-2.0%), and 2.3% of requisitions (1417/61 245; 95% CI = 1.2%-4.6%). Future research is needed to evaluate if hospitals are able to use these measures to assess interventions meant to reduce the frequency of specimen identification defects and improve patient safety.


Asunto(s)
Patología Quirúrgica , Sistemas de Identificación de Pacientes/normas , Indicadores de Calidad de la Atención de Salud , Manejo de Especímenes , Humanos , Iowa , Michigan , Seguridad del Paciente , Proyectos Piloto , Desarrollo de Programa , Mejoramiento de la Calidad
12.
BMJ Qual Saf ; 21(10): 872-5, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22562877

RESUMEN

Healthcare has made great efforts to reduce preventable patient harm, from externally driven regulations to internally driven professionalism. Regulation has driven the majority of efforts to date, and has a necessary place in establishing accountability and minimum standards. Yet they need to be coupled with internally driven efforts. Among professional groups, internally-driven efforts that function as communities of learning and change social norms are highly effective tools to improve performance, yet these approaches are underdeveloped in healthcare. Healthcare can learn much from the nuclear power industry. The nuclear power industry formed the Institute of Nuclear Power Operators following the Three Mile Island accident to improve safety. That organization established a peer-to-peer assessment program to cross-share best practices, safety hazards, problems and actions that improved safety and operational performance. This commentary explores how a similar program could be expanded into healthcare. Healthcare needs a structured, clinician-led, industry-wide process to openly review, identify and mitigate hazards, and share best practices that ultimately improve patient safety. A healthcare version of the nuclear power program could supplement regulatory and other strategies currently used to improve quality and patient safety.


Asunto(s)
Plantas de Energía Nuclear , Organizaciones de Normalización Profesional , Calidad de la Atención de Salud , Femenino , Humanos , Masculino , Estudios de Casos Organizacionales , Cambio Social
13.
Am J Med Qual ; 27(3): 201-9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22202557

RESUMEN

Health care has primarily used retrospective review approaches to identify and mitigate hazards, with little evidence of measurable and sustained improvements in patient safety. Conversely, the nuclear power industry has used a prospective peer-to-peer (P2P) assessment process grounded in open information exchange and cooperative organizational learning to realize substantial and sustainable improvements in safety. In comparing approaches, it is evident that health care's sluggish progress stems from weaknesses in hazard identification and mitigation and in organizational learning. This article proposes creating and implementing a structured prospective P2P assessment model in health care, similar to that used in the nuclear power industry, to accelerate improvements in patient safety.


Asunto(s)
Plantas de Energía Nuclear/normas , Revisión por Pares/métodos , Evaluación de Procesos, Atención de Salud/métodos , Garantía de la Calidad de Atención de Salud/organización & administración , Seguridad/normas , Humanos , Seguridad del Paciente/normas , Estudios Prospectivos , Garantía de la Calidad de Atención de Salud/métodos , Estudios Retrospectivos , Administración de la Seguridad/normas
14.
Acad Radiol ; 16(11): 1443-7, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19835789

RESUMEN

RATIONALE AND OBJECTIVES: The aim of this study was to verify earlier work on learning and retaining chest radiographic anatomy introduced during preclinical education and revisited in the clinical years by comparing the initial clinical group to clinical students in a second setting who had no preclinical exposure. MATERIALS AND METHODS: One hundred thirty-seven clinical medical students were pretested and posttested on the same 10 items as were used in the first study. Scores on these 10-item standardized pretests and posttests were compared and assessed for statistical significance. RESULTS: Although the clinical students with preclinical exposure scored significantly higher on the pretest than the students without preclinical exposure (mean, 4.42 vs 4.09), there was a much larger significant difference in posttest improvement (mean, 8.65 vs 6.09). Isolating only the senior students to control for clinical experience (pretest, 4.42 vs 4.38; posttest, 8.65 vs 6.09) did not significantly affect outcomes. CONCLUSIONS: Many medical schools are revising curricula and incorporating new models of learning. It may be important to recognize that older approaches such as memorization and testing are still necessary to start building the enormous "filing cabinet" of facts that must be cross-linked, revisited, and retrievable to contribute to a usable fund of medical knowledge.


Asunto(s)
Educación Médica/estadística & datos numéricos , Evaluación Educacional , Conocimientos, Actitudes y Práctica en Salud , Radiografía Torácica , Radiología/educación , Retención en Psicología , Estudiantes de Medicina/estadística & datos numéricos , Maryland , Facultades de Medicina/estadística & datos numéricos
15.
Ultramicroscopy ; 109(5): 667-71, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19101084

RESUMEN

Zirconium alloys are used in the nuclear industry as fuel rod cladding. They are chosen for this role because of their good mechanical properties and low thermal neutron absorption. Oxidation of these alloys by coolant is one of the chief limiting factors of the fuel burn-up efficiency. The aim of the present study is to understand these oxidation mechanisms. As a first step, a fundamental study of the oxidation of commercially pure zirconium has been conducted using the 3D atom probe (3DAP). The current generation of 3DAPs allows both voltage and laser pulsing, providing data sets of many millions of ions. According to the literature the only stable oxide of zirconium is ZrO(2). However, the 3DAP shows that an initial layer a few nanometres thick forms with a composition of ZrO(1-)(x) when subjected to light oxidation. This result confirms and extends the work of Wadman et al. [Colloque de Physique 50 (1989) C8 303; Journal de Physique, 11 (1988) C6 49] and Wadman and Andrén [in: C.M. Euchen, A.M. Garde (Eds.), Zirconium in the Nuclear Industry: Ninth Symposium, ASTM STP 1132, ASTM, USA, 1991, p. 461], who used 1DAP techniques, obtaining reduced data sets. Segregation of hydrogen to the metal-oxide interface and a distinct ZrH phase were observed in this study. A novel kinetics study of the room temperature oxidation of zirconium showed the ZrO layer to be non-protective over the time period investigated (up to 1h).

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