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1.
Cancer Discov ; 14(11): 2262-2278, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-38959428

RESUMO

Immunotherapies have shown great promise in pleural mesothelioma (PM), yet most patients still do not achieve significant clinical response, highlighting the importance of improving the understanding of the tumor microenvironment (TME). Here, we utilized high-throughput, single-cell RNA sequencing (scRNA-seq) to de novo identify 54 expression programs and construct a comprehensive cellular catalog of the PM TME. We found four cancer-intrinsic programs associated with poor disease outcome and a novel fetal-like, endothelial cell population that likely responds to VEGF signaling and promotes angiogenesis. Across cellular compartments, we observe substantial difference in the TME associated with a cancer-intrinsic sarcomatoid signature, including enrichment in fetal-like endothelial cells, CXCL9+ macrophages, and cytotoxic, exhausted, and regulatory T cells, which we validated using imaging and bulk deconvolution analyses on independent cohorts. Finally, we show, both computationally and experimentally, that NKG2A:HLA-E interaction between NK and tumor cells represents an important new therapeutic axis in PM, especially for epithelioid cases. Significance: This manuscript presents the first single-cell RNA sequencing atlas of PM tumor microenvironment. Findings of translational relevance, validated experimentally and using independent bulk cohorts, include identification of gene programs predictive of survival, a fetal-like endothelial cell population, and NKG2A blockade as a promising new immunotherapeutic intervention in PM.


Assuntos
Mesotelioma , Neoplasias Pleurais , Análise de Célula Única , Microambiente Tumoral , Humanos , Neoplasias Pleurais/patologia , Neoplasias Pleurais/genética , Mesotelioma/patologia , Mesotelioma/genética , Mesotelioma Maligno/patologia
2.
Int J Mol Sci ; 25(12)2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38928375

RESUMO

Microbes constitute the most prevalent life form on Earth, yet their remarkable diversity remains mostly unrecognized. Microbial diversity in vertebrate models presents a significant challenge for investigating host-microbiome interactions. The model organism Caenorhabditis elegans has many advantages for delineating the effects of host genetics on microbial composition. In the wild, the C. elegans gut contains various microbial species, while in the laboratory it is usually a host for a single bacterial species. There is a potential host-microbe interaction between microbial metabolites, drugs, and C. elegans phenotypes. This mini-review aims to summarize the current understanding regarding the microbiome in C. elegans. Examples using C. elegans to study host-microbe-metabolite interactions are discussed.


Assuntos
Caenorhabditis elegans , Animais , Caenorhabditis elegans/microbiologia , Caenorhabditis elegans/genética , Microbioma Gastrointestinal , Modelos Animais , Microbiota , Interações entre Hospedeiro e Microrganismos , Bactérias/genética , Bactérias/classificação , Bactérias/metabolismo
3.
Injury ; 55(9): 111523, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38614835

RESUMO

BACKGROUND: In patients with severe traumatic brain injury (TBI), clinicians must balance preventing venous thromboembolism (VTE) with the risk of intracranial hemorrhagic expansion (ICHE). We hypothesized that low molecular weight heparin (LMWH) would not increase risk of ICHE or VTE as compared to unfractionated heparin (UH) in patients with severe TBI. METHODS: Patients ≥ 18 years of age with isolated severe TBI (AIS ≥ 3), admitted to 24 level I and II trauma centers between January 1, 2014 to December 31, 2020 and who received subcutaneous UH and LMWH injections for chemical venous thromboembolism prophylaxis (VTEP) were included. Primary outcomes were VTE and ICHE after VTEP initiation. Secondary outcomes were mortality and neurosurgical interventions. Entropy balancing (EBAL) weighted competing risk or logistic regression models were estimated for all outcomes with chemical VTEP agent as the predictor of interest. RESULTS: 984 patients received chemical VTEP, 482 UH and 502 LMWH. Patients on LMWH more often had pre-existing conditions such as liver disease (UH vs LMWH 1.7 % vs. 4.4 %, p = 0.01), and coagulopathy (UH vs LMWH 0.4 % vs. 4.2 %, p < 0.001). There were no differences in VTE or ICHE after VTEP initiation. There were no differences in neurosurgical interventions performed. There were a total of 29 VTE events (3 %) in the cohort who received VTEP. A Cox proportional hazards model with a random effect for facility demonstrated no statistically significant differences in time to VTE across the two agents (p = 0.44). The LMWH group had a 43 % lower risk of overall ICHE compared to the UH group (HR = 0.57: 95 % CI = 0.32-1.03, p = 0.062), however was not statistically significant. CONCLUSION: In this multi-center analysis, patients who received LMWH had a decreased risk of ICHE, with no differences in VTE, ICHE after VTEP initiation and neurosurgical interventions compared to those who received UH. There were no safety concerns when using LMWH compared to UH. LEVEL OF EVIDENCE: Level III, Therapeutic Care Management.


Assuntos
Anticoagulantes , Lesões Encefálicas Traumáticas , Heparina de Baixo Peso Molecular , Pontuação de Propensão , Tromboembolia Venosa , Humanos , Tromboembolia Venosa/prevenção & controle , Lesões Encefálicas Traumáticas/complicações , Masculino , Feminino , Pessoa de Meia-Idade , Anticoagulantes/uso terapêutico , Heparina de Baixo Peso Molecular/uso terapêutico , Adulto , Heparina/uso terapêutico , Estudos Retrospectivos , Idoso , Hemorragias Intracranianas
4.
bioRxiv ; 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-37425718

RESUMO

TP53 is the most frequently mutated gene across many cancers and is associated with shorter survival in lung adenocarcinoma (LUAD). To define how TP53 mutations affect the LUAD tumor microenvironment (TME), we constructed a multi-omic cellular and spatial tumor atlas of 23 treatment-naïve human lung tumors. We found that TP53 -mutant ( TP53 mut ) malignant cells lose alveolar identity and upregulate highly proliferative and entropic gene expression programs consistently across resectable LUAD patient tumors, genetically engineered mouse models, and cell lines harboring a wide spectrum of TP53 mutations. We further identified a multicellular tumor niche composed of SPP1 + macrophages and collagen-expressing fibroblasts that coincides with hypoxic, pro-metastatic expression programs in TP53 mut tumors. Spatially correlated angiostatic and immune checkpoint interactions, including CD274 - PDCD1 and PVR - TIGIT , are also enriched in TP53 mut LUAD tumors, which may influence response to checkpoint blockade therapy. Our methodology can be further applied to investigate mutation-specific TME changes in other cancers.

5.
J Allergy Clin Immunol ; 152(6): 1569-1580, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37619819

RESUMO

BACKGROUND: Rising rates of peanut allergy (PA) motivate investigations of its development to inform prevention and therapy. Microbiota and the metabolites they produce shape food allergy risk. OBJECTIVE: We sought to gain insight into gut microbiome and metabolome dynamics in the development of PA. METHODS: We performed a longitudinal, integrative study of the gut microbiome and metabolome of infants with allergy risk factors but no PA from a multicenter cohort followed through mid-childhood. We performed 16S rRNA sequencing, short chain fatty acid measurements, and global metabolome profiling of fecal samples at infancy and at mid-childhood. RESULTS: In this longitudinal, multicenter sample (n = 122), 28.7% of infants developed PA by mid-childhood (mean age 9 years). Lower infant gut microbiome diversity was associated with PA development (P = .014). Temporal changes in the relative abundance of specific microbiota and gut metabolite levels significantly differed in children who developed PA. PA-bound children had different abundance trajectories of Clostridium sensu stricto 1 sp (false discovery rate (FDR) = 0.015) and Bifidobacterium sp (FDR = 0.033), with butyrate (FDR = 0.045) and isovalerate (FDR = 0.036) decreasing over time. Metabolites associated with PA development clustered within the histidine metabolism pathway. Positive correlations between microbiota, butyrate, and isovalerate and negative correlations with histamine marked the PA-free network. CONCLUSION: The temporal dynamics of the gut microbiome and metabolome in early childhood are distinct for children who develop PA. These findings inform our thinking on the mechanisms underlying and strategies for potentially preventing PA.


Assuntos
Microbioma Gastrointestinal , Hipersensibilidade a Amendoim , Criança , Pré-Escolar , Humanos , Lactente , Butiratos , Fezes/microbiologia , Microbioma Gastrointestinal/genética , Metaboloma , RNA Ribossômico 16S/genética , Estudos Longitudinais
6.
J Trauma Acute Care Surg ; 95(1): 94-104, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37017458

RESUMO

BACKGROUND: Patients with traumatic brain injury (TBI) are at high risk of venous thromboembolism events (VTE). We hypothesized that early chemical VTE prophylaxis initiation (≤24 hours of a stable head CT) in severe TBI would reduce VTE without increasing risk of intracranial hemorrhage expansion (ICHE). METHODS: A retrospective review of adult patients 18 years or older with isolated severe TBI (Abbreviated Injury Scale score, ≥ 3) who were admitted to 24 Level I and Level II trauma centers from January 1, 2014 to December 31 2020 was conducted. Patients were divided into those who did not receive any VTE prophylaxis (NO VTEP), who received VTE prophylaxis ≤24 hours after stable head CT (VTEP ≤24) and who received VTE prophylaxis >24 hours after stable head CT (VTEP>24). Primary outcomes were VTE and ICHE. Covariate balancing propensity score weighting was utilized to balance demographic and clinical characteristics across three groups. Weighted univariate logistic regression models were estimated for VTE and ICHE with patient group as predictor of interest. RESULTS: Of 3,936 patients, 1,784 met inclusion criteria. Incidences of VTE was significantly higher in the VTEP>24 group, with higher incidences of DVT in the group. Higher incidences of ICHE were observed in the VTEP≤24 and VTEP>24 groups. After propensity score weighting, there was a higher risk of VTE in patients in VTEP >24 compared with those in VTEP≤24 (odds ratio, 1.51; 95% confidence interval, 0.69-3.30; p = 0.307), however was not significant. Although, the No VTEP group had decreased odds of having ICHE compared with VTEP≤24 (odds ratio, 0.75; 95% confidence interval, 0.55-1.02, p = 0.070), the result was not statistically significant. CONCLUSION: In this large multi-center analysis, there were no significant differences in VTE based on timing of initiation of VTE prophylaxis. Patients who never received VTE prophylaxis had decreased odds of ICHE. Further evaluation of VTE prophylaxis in larger randomized studies will be necessary for definitive conclusions. LEVEL OF EVIDENCE: Therapeutic Care Management; Level III.


Assuntos
Lesões Encefálicas Traumáticas , Tromboembolia Venosa , Adulto , Humanos , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/prevenção & controle , Pontuação de Propensão , Resultado do Tratamento , Anticoagulantes/uso terapêutico , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/tratamento farmacológico , Hemorragias Intracranianas/induzido quimicamente , Estudos Retrospectivos
7.
BMJ Open Qual ; 12(1)2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36958791

RESUMO

BACKGROUND: Over-ordering of daily laboratory tests adversely affects patient care through hospital-acquired anaemia, patient discomfort, burden on front-line staff and unnecessary downstream testing. This remains a prevalent issue despite the 2013 Choosing Wisely recommendation to minimise unnecessary daily labs. We conducted a systematic review of the literature to identify interventions targeting unnecessary laboratory testing. METHODS: We systematically searched MEDLINE, EMBASE, Cochrane Central and SCOPUS databases to identify interventions focused on reducing daily complete blood count, complete metabolic panel and basic metabolic panel labs. We defined interventions as 'effective' if a statistically significant reduction was attained and 'highly effective' if a reduction of ≥25% was attained. RESULTS: The search yielded 5646 studies with 41 articles that met inclusion criteria. We grouped interventions into one or more categories: audit and feedback, cost display, education, electronic medical record (EMR) change, and policy change. Most interventions lasted less than a year and used a multipronged approach. All five strategies were effective in most studies with EMR change being the most commonly used independent strategy. EMR change and policy change were the strategies most frequently reported as effective. EMR change was the strategy most frequently reported as highly effective. CONCLUSION: Our analysis identified five categories of interventions targeting daily laboratory testing. All categories were effective in most studies, with EMR change being most frequently highly effective. PROSPERO REGISTRATION NUMBER: CRD42021254076.


Assuntos
Técnicas de Laboratório Clínico , Procedimentos Desnecessários , Humanos , Pacientes Internados
8.
Front Psychiatry ; 13: 927856, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36172512

RESUMO

Background: Stroke is a major cause of mortality and long-term physical and cognitive impairment. This study aims to: (1) examine the prevalence of depressive symptoms, disability and pain among Chinese adults with stroke; (2) test the associations of functional limitations and body pain with occurrence of depressive symptoms; (3) investigate gender and urban-rural disparities in these associations. Methods: This study utilized the data from the China Health and Retirement Longitudinal Study in 2018, involving 969 patients with stroke among 17,970 participants aged ≥ 45 years. Depressive symptoms were assessed using the 10-item Center for Epidemiologic Studies Depression (CES-D) Scale. We performed multivariable logistic regression models to estimate the associations between activities of daily life (ADL), instrumental activities of daily life (IADL) and pain with depressive symptoms. Results: Depressive symptoms were found among 40.2% of stroke patients, with a higher prevalence in females (48.2%) than males (32.7%). Prevalence of ADL limitations, IADL limitations and pain among stroke patients were 39.2, 49.8 and 14.0%, respectively. ADL and IADL limitations and pain were more prevalent among females and residents in rural areas. Multivariable regression analyses showed a significant association between ADL limitation (OR = 1.535, 95% CI = 1.168, 2.018), IADL limitation (OR = 1.666, 95% CI = 1.260, 2.203) and pain (OR = 2.122, 95% CI = 1.466, 3.073) with depressive symptoms. Stratified analyses revealed stronger associations among urban residents. Females had a higher association of ADL and IADL with depressive symptoms but similar in that of pain to the males. The impact of ADL and IADL in male patients is higher than in females, but the impact of pain on depressive symptoms is higher in female patients. Conclusion: Depressive symptoms are common amongst post-stroke patients in China and are significantly associated with functional disability and physical pain. Our findings have implications for practitioners on the early assessment of pain and depression after stroke. Future research should explore effective intervention measures for physical-mental stroke complications.

9.
Front Pediatr ; 9: 622254, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34178880

RESUMO

Background: The novel coronavirus and its effect on our society are unprecedented. Given the recent pandemic, numerous measures have been taken to protect our communities. We sought to understand our school community's knowledge and the measures that were taken by our school for our safety. Objective: Our objective was to describe the overall understanding and attitudes of 8-12th grade students from a single institution during the initial phase of the Wisconsin's Governor's stay-at-home order. Methods: A voluntary web-based survey was communicated to 8-12th grade students through their online school portal. Data were collected and analyzed using SurveyMonkey. Results: There was a 20.2% response rate. Answers regarding the coronavirus, spread, and response to the coronavirus pandemic showed a high level of understanding of the virus and the actions necessary to prevent its spread. Conclusion: Eight-twelfth grade students have a high level of understanding of the virus, its effects, and the safety measures implemented to protect society.

10.
Nano Lett ; 20(2): 963-970, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31910625

RESUMO

Covalent organic frameworks (COFs) are molecule-based 2D and 3D materials that possess a wide range of mechanical and electronic properties. We have performed a joint experimental and theoretical study of the electronic structure of boroxine-linked COFs grown under ultrahigh vacuum conditions and characterized using scanning tunneling spectroscopy on Au(111) and hBN/Cu(111) substrates. Our results show that a single hBN layer electronically decouples the COF from the metallic substrate, thus suppressing substrate-induced broadening and revealing new features in the COF electronic local density of states (LDOS). The resulting sharpening of LDOS features allows us to experimentally determine the COF band gap, bandwidths, and the electronic hopping amplitude between adjacent COF bridge sites. These experimental parameters are consistent with the results of first-principles theoretical predictions.

11.
Ann Allergy Asthma Immunol ; 122(3): 276-282, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30578857

RESUMO

OBJECTIVE: To review observational human, murine, and interventional trial studies that have examined the gut microbiome in food allergy, and to provide perspective on future investigations in this field. DATA SOURCES: A review of the published literature was performed with PubMed, and clinical studies catalogued at ClinicalTrials.gov were also reviewed. STUDY SELECTIONS: The most recent relevant studies, seminal works, and topical clinical trials were selected. RESULTS: Gut dysbiosis likely precedes the development of food allergy, and the timing of such dysbiosis is critical. Gut microbiota associated with individual food allergies may be distinct. Murine models support the importance of gut microbiota in shaping immune maturation and tolerance. Gut microbiota may affect food allergy susceptibility by modulating type 2 immunity, influencing immune development and tolerance, regulating basophil populations, and promoting intestinal barrier function. Ongoing and future interventional trials of probiotics, prebiotics, synbiotics, and fecal microbiota transfer will help translate our understanding of the gut microbiome in food allergy to clinical practice. Future work in this area will include deepening of current research foci, as well as expansion of efforts to include the virome, mycobiome, and interactions between the microbiome, host, and environment. Robust and consistent study designs, multidimensional profiling, and systems biology approaches will enable this future work. CONCLUSION: By advancing research on the microbiome in food allergy, we can further our understanding of food allergy and derive new approaches for its prevention and therapy.


Assuntos
Hipersensibilidade Alimentar/microbiologia , Microbioma Gastrointestinal , Animais , Humanos
12.
ACS Nano ; 12(3): 2193-2200, 2018 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-29381853

RESUMO

Bottom-up graphene nanoribbon (GNR) heterojunctions are nanoscale strips of graphene whose electronic structure abruptly changes across a covalently bonded interface. Their rational design offers opportunities for profound technological advancements enabled by their extraordinary structural and electronic properties. Thus far, the most critical aspect of their synthesis, the control over sequence and position of heterojunctions along the length of a ribbon, has been plagued by randomness in monomer sequences emerging from step-growth copolymerization of distinct monomers. All bottom-up GNR heterojunction structures created so far have exhibited random sequences of heterojunctions and, while useful for fundamental scientific studies, are difficult to incorporate into functional nanodevices as a result. In contrast, we describe a hierarchical fabrication strategy that allows the growth of bottom-up GNRs that preferentially exhibit a single heterojunction interface rather than a random statistical sequence of junctions along the ribbon. Such heterojunctions provide a viable platform that could be directly used in functional GNR-based device applications at the molecular scale. Our hierarchical GNR fabrication strategy is based on differences in the dissociation energies of C-Br and C-I bonds that allow control over the growth sequence of the block copolymers from which GNRs are formed and consequently yields a significantly higher proportion of single-junction GNR heterostructures. Scanning tunneling spectroscopy and density functional theory calculations confirm that hierarchically grown heterojunctions between chevron GNR (cGNR) and binaphthyl-cGNR segments exhibit straddling Type I band alignment in structures that are only one atomic layer thick and 3 nm in width.

13.
Clin Cancer Res ; 23(11): 2869-2879, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27881580

RESUMO

Purpose: Although autophagy plays important roles in malignant pathogenesis and drug resistance, there are few clinical agents that disrupt this pathway, and the potential therapeutic benefit of autophagy inhibition remains undetermined. We used medicinal chemistry approaches to generate a series of novel agents that inhibit autophagic degradation.Experimental Design: ROC-325 was selected as a lead compound for further evaluation. Comprehensive in vitro and in vivo studies were conducted to evaluate the selectivity, tolerability, and efficacy of ROC-325 in preclinical models of renal cell carcinoma (RCC) with HCQ serving as a comparator. Markers of autophagy inhibition and cell death were evaluated in tumor specimens.Results: ROC-325 exhibited superior in vitro anticancer effects compared with the existing autophagy inhibitor hydroxychloroquine (HCQ) in 12 different cancer cell lines with diverse genetic backgrounds. Focused studies of the mechanism of action and efficacy of ROC-325 in RCC cells showed that drug treatment induced hallmark characteristics of autophagy inhibition, including accumulation of autophagosomes with undegraded cargo, lysosomal deacidification, p62 stabilization, and disruption of autophagic flux. Subsequent experiments showed that ROC-325 antagonized RCC growth and survival in an ATG5/7-dependent manner, induced apoptosis, and exhibited favorable selectivity. Oral administration of ROC-325 to mice bearing 786-0 RCC xenografts was well tolerated, was significantly more effective at inhibiting tumor progression than HCQ, and inhibited autophagy in vivoConclusions: Our findings demonstrate that ROC-325 has superior preclinical anticancer activity compared with HCQ and support the clinical investigation of its safety and preliminary efficacy in patients with RCC and other autophagy-dependent malignancies. Clin Cancer Res; 23(11); 2869-79. ©2016 AACR.


Assuntos
Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Carcinoma de Células Renais/tratamento farmacológico , Animais , Apoptose/genética , Autofagia/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Humanos , Hidroxicloroquina/administração & dosagem , Hidroxicloroquina/análogos & derivados , Hidroxicloroquina/farmacologia , Lisossomos/efeitos dos fármacos , Camundongos , Proteólise/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
14.
PLoS One ; 9(10): e107939, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25280009

RESUMO

The apicomplexan intraerythrocytic parasite Babesia microti is an emerging human pathogen and the primary cause of human babesiosis, a malaria-like illness endemic in the United States. The pathogen is transmitted to humans by the tick vector, Ixodes scapularis, and by transfusion of blood from asymptomatic B. microti-infected donors. Whereas the nuclear and mitochondrial genomes of this parasite have been sequenced, assembled and annotated, its apicoplast genome remained incomplete, mainly due to its low representation and high A+T content. Here we report the complete sequence and annotation of the apicoplast genome of the B. microti R1 isolate. The genome consists of a 28.7 kb circular molecule encoding primarily functions important for maintenance of the apicoplast DNA, transcription, translation and maturation of organellar proteins. Genome analysis and annotation revealed a unique gene structure and organization of the B. microti apicoplast genome and suggest that all metabolic and non-housekeeping functions in this organelle are nuclear-encoded. B. microti apicoplast functions are significantly different from those of the host, suggesting that they might be useful as targets for development of potent and safe therapies for the treatment of human babesiosis.


Assuntos
Apicoplastos/genética , Babesia microti/genética , Genomas de Plastídeos , Anotação de Sequência Molecular , Babesia microti/classificação , Babesiose/parasitologia , Ordem dos Genes , Humanos , Dados de Sequência Molecular , Família Multigênica , Filogenia , Análise de Sequência de DNA
15.
J Biomed Mater Res B Appl Biomater ; 100(2): 409-15, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22102276

RESUMO

UNLABELLED: Polymethyl methacrylate (PMMA) is widely used to treat traumatic head injuries (cranioplasty) and orthopedic injuries (bone cement), but there is a problem with implant-centered infections. With organisms such as Acinetobacter baumannii and methicillin-resistant staphylococcus aureus developing resistance to antibiotics, there is a need for novel antimicrobial delivery mechanisms without risk of developing resistant organisms. OBJECTIVES: To develop a novel antimicrobial implant material by generating silver nanoparticles (AgNP) in situ in PMMA. RESULTS: All PMMA samples with AgNP's (AgNP-PMMA) released Ag(+) ions in vitro for over 28 days. In vitro antimicrobial assays revealed that these samples (even samples with the slowest release rate) inhibited 99.9% of bacteria against four different strains of bacteria. Long-term antimicrobial assay showed a continued antibacterial effect past 28 days. Some AgNP-loaded PMMA groups had comparable Durometer-D hardness (a measure of degree of cure) and modulus to control PMMA, but all experimental groups had slightly lower ultimate transverse strengths. CONCLUSIONS: AgNP-PMMA demonstrated a tremendously broad-spectrum and long-intermediate-term antimicrobial effect with comparable mechanical properties to control PMMA. Current efforts are focused on further improving mechanical properties by reducing AgNP loading and assessing fatigue properties.


Assuntos
Acinetobacter baumannii/crescimento & desenvolvimento , Antibacterianos , Nanopartículas Metálicas/química , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Polimetil Metacrilato , Prata , Antibacterianos/química , Antibacterianos/farmacologia , Polimetil Metacrilato/química , Polimetil Metacrilato/farmacologia , Prata/química , Prata/farmacologia
16.
J Neuropathol Exp Neurol ; 68(6): 661-76, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19458542

RESUMO

Polyethylene glycol (PEG) has been reported to possess fusogenic properties that may confer neuroprotection after spinal cord injury (SCI), but there is uncertainty regarding the mechanisms of PEG in vivo and the robustness of its protective effects. We hypothesized that PEG promotes preservation of cytoskeletal proteins associated with white matter protection and neurobehavioral recovery after SCI. In proof-of-principle experiments using a pin-drop organotypic culture model of SCI, PEG attenuated neural cell death. Adult rats underwent 35-g clip compression SCI at C8 and were randomized postinjury to receive intravenous 30% PEG or sterile Ringer's lactate solution. Confocal microscopy and high-performance liquid chromatography of fluorescein-conjugated PEG permitted in vivo quantification of PEG concentrations in the injured and uninjured spinal cord. Western blot, immunohistochemistry, and terminal deoxynucleotidyl transferase mediated dUTP nick end labeling staining demonstrated that PEG reduced 200-kd neurofilament degradation and apoptotic cell death. Polyethylene glycol also promoted spinal cord tissue sparing based on retrograde axonal Fluoro-Gold tracing and morphometric histological assessment. Polyethylene glycol also promoted significant, although modest, neurobehavioral recovery after SCI. Collectively, these results indicate that PEG protects key axonal cytoskeletal proteins after SCI, and that the protection is associated with axonal preservation. The modest extent of locomotor recovery after treatment with PEG suggests, however, that this compound may notconfer sufficient neuroprotection to be used clinically as a single treatment.


Assuntos
Fármacos Neuroprotetores/uso terapêutico , Polietilenoglicóis/uso terapêutico , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/patologia , Análise de Variância , Animais , Vértebras Cervicais , Proteínas do Citoesqueleto/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Marcação In Situ das Extremidades Cortadas/métodos , Técnicas In Vitro , Indóis , Atividade Motora/efeitos dos fármacos , Proteínas de Neurofilamentos/metabolismo , Fármacos Neuroprotetores/farmacologia , Fosfopiruvato Hidratase/metabolismo , Polietilenoglicóis/farmacologia , Desempenho Psicomotor/efeitos dos fármacos , Ratos , Ratos Wistar , Recuperação de Função Fisiológica/efeitos dos fármacos , Estilbamidinas , Fatores de Tempo
17.
Clin Trials ; 4(3): 286-91, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17715258

RESUMO

In analysing clinical trials designed to show superiority of one treatment compared to another, it is standard to use an intention to treat analytic approach. In active-controlled noninferiority studies, this is not standard, due to concerns that such an analysis will inflate the chance of falsely rejecting the null hypothesis, accepting therapeutic noninferiority when it is not justified. The reasons for using intention to treat (ITT) approaches in superiority studies include a desire to capture all information on study subjects, a need to prevent bias, and assurance that comparative groups are, on average, equivalent in prognostic factors. In this commentary, we argue that these same justifications carry over to noninferiority studies, and that for those and other reasons it should be the preferred analytic approach. We review regulatory guidelines, and propose a number of approaches to minimizing the potential disadvantages of the ITT approach in the noninferiority setting.


Assuntos
Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Viés , Humanos , Pacientes Desistentes do Tratamento , Seleção de Pacientes
18.
Am J Ther ; 10(1): 12-20, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12522515

RESUMO

The aim of this study was to evaluate the utility of the American Pain Society (APS) questionnaire in the assessment of osteoarthritis (OA) pain and to determine the onset of action of celecoxib in the treatment of acute flare pain in patients with OA of the knee or hip. Pooled data from three pivotal, randomized, double-blind, placebo-controlled, 12-week trials of patients with OA who exhibited a flare of disease activity after withdrawal of nonsteroidal anti-inflammatory drug or analgesic therapy were evaluated. Patients completed the APS Pain Measure Questionnaire, which evaluates pain intensity and quality of life, at baseline and daily for the first 7 days of therapy. In addition, patients underwent a range of standard OA assessments to evaluate the analgesic efficacy of celecoxib up to 12 weeks. Three thousand two hundred fifty-eight patients were enrolled in the three studies, of whom 2041 completed the APS questionnaire (1010 received celecoxib, 513 received naproxen, and 518 received placebo). Within the first 24 hours, celecoxib at a dose of 200 or 400 mg/d significantly reduced the amount of acute pain experienced compared with placebo for four of the five measures, and statistical significance for the remaining parameter, "pain in the last 24 hours," was achieved on day 2. Celecoxib at a dose of 200 to 400 mg/d provided similar efficacy to naproxen at a dose of 1000 mg/d. The pain relief observed with celecoxib was maintained for the APS evaluation period. Long-term efficacy assessments showed the efficacy of 200 mg/d of celecoxib to be continuous and maintained for at least the 12 weeks of the study and that it was equivalent to 400 mg/d of celecoxib and 1000 mg/d of naproxen. This study demonstrates that the APS questionnaire is a useful measure of pain and therapeutic response in OA. Celecoxib furthermore seems to be an effective acute and chronic analgesic in OA.


Assuntos
Inibidores de Ciclo-Oxigenase/uso terapêutico , Naproxeno/uso terapêutico , Osteoartrite/tratamento farmacológico , Medição da Dor , Dor/tratamento farmacológico , Sulfonamidas/uso terapêutico , Idoso , Celecoxib , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Naproxeno/administração & dosagem , Dor/etiologia , Pirazóis , Ensaios Clínicos Controlados Aleatórios como Assunto , Sulfonamidas/administração & dosagem
19.
Eur J Gastroenterol Hepatol ; 14(10): 1101-11, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12362101

RESUMO

OBJECTIVE: To determine whether valdecoxib, at chronic arthritis doses, has the characteristics of a cyclo-oxygenase 2 (COX-2) specific inhibitor, as measured by a reduced incidence of upper-gastrointestinal ulceration compared with conventional nonsteroidal anti-inflammatory drugs (NSAIDs). METHODS: This double-blind, multicentre, placebo-controlled, parallel-group study compared the incidence of gastroduodenal ulcers associated with valdecoxib 10 mg daily (q.d.) and 20 mg q.d. with that of ibuprofen 800 mg three times daily (t.i.d.) or diclofenac 75 mg twice daily (b.i.d.) when administered over a 12-week period. The incidence of gastroduodenal ulcers was assessed by upper-gastrointestinal endoscopy, performed at baseline and again at the end of week 12 (or at early study termination). Efficacy assessments were performed at baseline and at weeks 2, 6 and 12 using Patient's and Physician's Global Assessments of Arthritis. RESULTS: A total of 1052 osteoarthritis patients were enrolled into the trial. The incidence of gastroduodenal ulcers over 12 weeks was 5% in patients receiving valdecoxib 10 mg q.d., 4% in patients receiving valdecoxib 20 mg q.d., 7% in patients receiving placebo, 16% in patients receiving ibuprofen 800 mg t.i.d. (P <0.05 v. placebo), and 17% in patients receiving diclofenac 75 mg b.i.d. (P <0.05 v. placebo). The incidence of gastroduodenal ulcers at week 12 seen in the ibuprofen 800 mg t.i.d. and diclofenac 75 mg b.i.d. groups was significantly higher than that in the valdecoxib 10 mg q.d. and valdecoxib 20 mg q.d. groups (P <0.05). The incidence rates of gastroduodenal ulcers were not significantly different between the valdecoxib treatment groups or between valdecoxib- and placebo-treated patients. Efficacy responses to valdecoxib 10 mg and 20 mg q.d. were significantly greater than placebo and comparable with both ibuprofen 800 mg t.i.d. and diclofenac 75 mg b.i.d. CONCLUSIONS: The results of the study demonstrate that valdecoxib has an upper-gastrointestinal safety profile typical of a COX-2 specific inhibitor. Overall, the data indicate that administration of valdecoxib offers similar efficacy for the treatment of osteoarthritis but improved upper-gastrointestinal safety compared with the conventional NSAIDs, ibuprofen and diclofenac, based on the significantly lower incidence of gastroduodenal ulcers detected by endoscopy.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Diclofenaco/efeitos adversos , Ibuprofeno/efeitos adversos , Isoxazóis/efeitos adversos , Osteoartrite/tratamento farmacológico , Úlcera Péptica/induzido quimicamente , Sulfonamidas/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Ciclo-Oxigenase 2 , Método Duplo-Cego , Úlcera Duodenal/induzido quimicamente , Úlcera Duodenal/microbiologia , Feminino , Infecções por Helicobacter/complicações , Helicobacter pylori , Humanos , Isoenzimas/antagonistas & inibidores , Masculino , Proteínas de Membrana , Pessoa de Meia-Idade , Úlcera Péptica/microbiologia , Prostaglandina-Endoperóxido Sintases , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/microbiologia , Resultado do Tratamento
20.
J Fam Pract ; 51(6): 530-7, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12100776

RESUMO

OBJECTIVE: We compared the efficacy and upper gastrointestinal safety of the cyclooxygenase-2-specific inhibitor valdecoxib with naproxen and placebo in treating moderate to severe osteoarthritis of the knee. STUDY DESIGN: This multicenter, randomized, double-blind, placebo-controlled study compared the efficacy and upper gastrointestinal tract safety of valdecoxib at dosages of 5, 10, and 20 mg once daily with placebo and naproxen at the dosage of 500 mg twice daily. POPULATION: We included patients who had been diagnosed with moderate to severe osteoarthritis of the knee according to the modified criteria of the American College of Rheumatology. OUTCOMES MEASURED: The Patient's and Physician's Global Assessment of Arthritis (PaGAA, PhGAA), Patient's Assessment of Arthritis Pain-Visual Analog Scale (PAAP-VAS), and Western Ontario and McMaster's Universities (WOMAC) Osteoarthritis indices were assessed at baseline and at weeks 2, 6, and 12. Upper gastrointestinal ulceration was assessed by pre- and posttreatment endoscopies. RESULTS: Valdecoxib 10 and 20 mg once daily (but not 5 mg once daily) demonstrated similar efficacy to naproxen at 500 mg twice daily, and all 3 dosages were superior to placebo for the PaGAA, PhGAA, PAAP-VAS, and WOMAC Osteoarthritis indices at most assessments throughout the 12-week study (P <.05). The incidence of endoscopically proven ulcers was significantly higher in the naproxen group than in the 5- and 10-mg valdecoxib groups, but not in the 20-mg valdecoxib group. All 3 valdecoxib doses were comparable to placebo in ulcer incidence. CONCLUSIONS: Valdecoxib (10 and 20 mg once daily) is significantly superior to placebo and as effective as naproxen (500 mg twice daily) in improving moderate to severe osteoarthritis of the knee. Upper gastrointestinal tract safety of valdecoxib (5 and 10 mg) was comparable to that of placebo and significantly better than that of naproxen.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Sistema Digestório/efeitos dos fármacos , Isoxazóis/uso terapêutico , Naproxeno/uso terapêutico , Osteoartrite/tratamento farmacológico , Sulfonamidas/uso terapêutico , Idoso , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/farmacologia , Método Duplo-Cego , Feminino , Humanos , Isoxazóis/efeitos adversos , Isoxazóis/farmacologia , Masculino , Pessoa de Meia-Idade , Naproxeno/efeitos adversos , Naproxeno/farmacologia , Medição da Dor , Sulfonamidas/efeitos adversos , Sulfonamidas/farmacologia , Resultado do Tratamento
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