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1.
Anticancer Drugs ; 35(5): 450-458, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38452059

RESUMO

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.


Assuntos
Neoplasias dos Genitais Femininos , Neoplasias , Adulto , Feminino , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias dos Genitais Femininos/induzido quimicamente , Neoplasias dos Genitais Femininos/tratamento farmacológico , Dose Máxima Tolerável , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Compostos de Fenilureia/efeitos adversos , Piridinas/uso terapêutico , Citrato de Sildenafila/efeitos adversos
2.
Dev Dyn ; 251(11): 1880-1896, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35809036

RESUMO

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.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Botões de Extremidades , Animais , Botões de Extremidades/metabolismo , Xenopus laevis/genética , Xenopus laevis/metabolismo , Mesoderma/metabolismo , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/metabolismo , Tretinoína/metabolismo , Extremidades , Expressão Gênica , Ectoderma/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas do Tecido Nervoso/genética , Proteínas de Xenopus/genética , Proteínas de Xenopus/metabolismo
3.
Int J Med Microbiol ; 312(2): 151549, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35114582

RESUMO

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.


Assuntos
Microbiota , Manejo de Espécimes , Colo , Fezes , RNA Ribossômico 16S/genética , Manejo de Espécimes/métodos
4.
Wound Repair Regen ; 30(6): 636-651, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35212086

RESUMO

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.


Assuntos
Lipopolissacarídeos , Microbiota , Animais , Antibacterianos , Larva/fisiologia , Lipopolissacarídeos/farmacologia , RNA Ribossômico 16S , Receptor 4 Toll-Like/metabolismo , Cicatrização , Xenopus laevis/genética , Xenopus laevis/metabolismo
5.
Magn Reson Chem ; 58(2): 198-203, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31692051

RESUMO

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.


Assuntos
Espectroscopia de Ressonância Magnética Nuclear de Carbono-13/métodos , Espectroscopia de Prótons por Ressonância Magnética/métodos , Tricotecenos/química , Oryza/microbiologia , Stachybotrys/metabolismo
6.
FEMS Microbiol Ecol ; 100(11)2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39317670

RESUMO

Skin microbes play an important role in amphibian tissue regeneration. Xenopus spp. (African clawed frogs) are well-established model organisms, and standard husbandry protocols, including use of antibiotics, may affect experimental outcomes by altering bacterial assemblages. It is therefore essential to improve knowledge of Xenopus bacterial community characteristics and inheritance. We undertook bacterial 16S rRNA gene sequencing and source tracking of a captive Xenopus laevis colony, including various life stages and environmental samples across multiple aquarium systems. Tank environments supported the most complex bacterial communities, while egg jelly bacteria were the most diverse of frog life stages; tadpole bacterial communities were relatively simple. Rhizobium (Proteobacteria) and Chryseobacterium (Bacteroidota) were dominant in tadpoles, whereas Chryseobacterium, Vogesella (Proteobacteria), and Acinetobacter (Proteobacteria) were common in females. Tadpoles received approximately two-thirds of their bacteria via vertical transmission, though 23 genera were differentially abundant between females and tadpoles. Female frog skin appears to select for specific taxa, and while tadpoles inherit a proportion of their skin bacteria from females via the egg, they support a distinct and less diverse community. The outcomes of this study suggest the impacts of breaking the bacterial transmission chain with antibiotic treatment should be considered when raising tadpoles for experimental purposes.


Assuntos
Bactérias , Larva , Microbiota , RNA Ribossômico 16S , Pele , Xenopus laevis , Animais , Bactérias/genética , Bactérias/classificação , Bactérias/isolamento & purificação , RNA Ribossômico 16S/genética , Pele/microbiologia , Feminino , Larva/microbiologia , Larva/crescimento & desenvolvimento , DNA Bacteriano/genética , Masculino
7.
medRxiv ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38712133

RESUMO

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.

8.
Nat Commun ; 15(1): 179, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167814

RESUMO

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.


Assuntos
Microbiota , Nova Zelândia , RNA Ribossômico 16S/genética , Filogenia , Metagenoma
9.
Cancer Chemother Pharmacol ; 91(3): 281-290, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36864346

RESUMO

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.


Assuntos
Ácidos Hidroxâmicos , Leucemia Mieloide Aguda , Humanos , Animais , Camundongos , Ácidos Hidroxâmicos/efeitos adversos , Pirimidinonas/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/patologia
10.
J Health Psychol ; 26(6): 880-891, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-31144526

RESUMO

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.


Assuntos
Qualidade de Vida , Fraturas do Ombro , Adulto , Idoso , Humanos , Úmero , Dor , Pesquisa Qualitativa
11.
Hand Clin ; 36(2): 171-180, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32307047

RESUMO

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.


Assuntos
Traumatismos da Mão/cirurgia , Mãos/cirurgia , Ortopedia , Aprovação de Equipamentos/legislação & jurisprudência , Educação de Pós-Graduação em Medicina , Regulamentação Governamental , Humanos , Ortopedia/educação , Ortopedia/organização & administração , Apoio à Pesquisa como Assunto , Medicina Estatal , Reino Unido
12.
Ultramicroscopy ; 109(5): 667-71, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19101084

RESUMO

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).

13.
Am J Med Qual ; 28(4): 308-14, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23322909

RESUMO

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.


Assuntos
Patologia Cirúrgica , Sistemas de Identificação de Pacientes/normas , Indicadores de Qualidade em Assistência à Saúde , Manejo de Espécimes , Humanos , Iowa , Michigan , Segurança do Paciente , Projetos Piloto , Desenvolvimento de Programas , Melhoria de Qualidade
14.
BMJ Qual Saf ; 21(10): 872-5, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22562877

RESUMO

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.


Assuntos
Centrais Nucleares , Organizações de Normalização Profissional , Qualidade da Assistência à Saúde , Feminino , Humanos , Masculino , Estudos de Casos Organizacionais , Mudança Social
15.
Am J Med Qual ; 27(3): 201-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22202557

RESUMO

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.


Assuntos
Centrais Nucleares/normas , Revisão por Pares/métodos , Avaliação de Processos em Cuidados de Saúde/métodos , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Segurança/normas , Humanos , Segurança do Paciente/normas , Estudos Prospectivos , Garantia da Qualidade dos Cuidados de Saúde/métodos , Estudos Retrospectivos , Gestão da Segurança/normas
16.
Acad Radiol ; 16(11): 1443-7, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19835789

RESUMO

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.


Assuntos
Educação Médica/estatística & dados numéricos , Avaliação Educacional , Conhecimentos, Atitudes e Prática em Saúde , Radiografia Torácica , Radiologia/educação , Retenção Psicológica , Estudantes de Medicina/estatística & dados numéricos , Maryland , Faculdades de Medicina/estatística & dados numéricos
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