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1.
Integr Org Biol ; 4(1): obac024, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35899093

RESUMO

Long-axis rotation (LAR) of the jaws may be an important component of vertebrate feeding mechanisms, as it has been hypothesized to occur during prey capture or food processing across diverse vertebrate groups including mammals, ray-finned fishes, and sharks and rays. LAR can affect tooth orientation as well as muscle fiber direction and therefore muscle power during feeding. However, to date only a handful of studies have demonstrated this LAR in vivo. Here, we use XROMM to document LAR of the upper and lower jaws in white-spotted bamboo sharks, Chiloscyllium plagiosum, during suction feeding. As the lower jaw begins to depress for suction expansion, both the upper jaw (palatoquadrate) and lower jaw (Meckel's cartilage) evert, such that their toothed surfaces move laterally, and then they invert with jaw closing. Eversion has been shown to tense the dental ligament and erect the teeth in some sharks, but it is not clear how this tooth erection would contribute to suction feeding in bamboo sharks. Two recent XROMM studies have shown LAR of the lower jaws during mastication in mammals and stingrays and our study extends LAR to suction feeding and confirms its presence in shark species. Examples of LAR of the jaws are becoming increasingly widespread across vertebrates with unfused mandibular symphyses. Unfused lower jaws are the plesiomorphic condition for most vertebrate lineages and therefore LAR may be a common component of jaw mechanics unless the mandibular symphysis is fused.

2.
PeerJ ; 10: e13517, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35642200

RESUMO

Background: Single camera markerless motion capture has the potential to facilitate at home movement assessment due to the ease of setup, portability, and affordable cost of the technology. However, it is not clear what the current healthcare applications of single camera markerless motion capture are and what information is being collected that may be used to inform clinical decision making. This review aims to map the available literature to highlight potential use cases and identify the limitations of the technology for clinicians and researchers interested in the collection of movement data. Survey Methodology: Studies were collected up to 14 January 2022 using Pubmed, CINAHL and SPORTDiscus using a systematic search. Data recorded included the description of the markerless system, clinical outcome measures, and biomechanical data mapped to the International Classification of Functioning, Disability and Health Framework (ICF). Studies were grouped by patient population. Results: A total of 50 studies were included for data collection. Use cases for single camera markerless motion capture technology were identified for Neurological Injury in Children and Adults; Hereditary/Genetic Neuromuscular Disorders; Frailty; and Orthopaedic or Musculoskeletal groups. Single camera markerless systems were found to perform well in studies involving single plane measurements, such as in the analysis of infant general movements or spatiotemporal parameters of gait, when evaluated against 3D marker-based systems and a variety of clinical outcome measures. However, they were less capable than marker-based systems in studies requiring the tracking of detailed 3D kinematics or fine movements such as finger tracking. Conclusions: Single camera markerless motion capture offers great potential for extending the scope of movement analysis outside of laboratory settings in a practical way, but currently suffers from a lack of accuracy where detailed 3D kinematics are required for clinical decision making. Future work should therefore focus on improving tracking accuracy of movements that are out of plane relative to the camera orientation or affected by occlusion, such as supination and pronation of the forearm.


Assuntos
Captura de Movimento , Movimento , Adulto , Criança , Humanos , Marcha , Inquéritos e Questionários , Atenção à Saúde
3.
Oral Dis ; 27(6): 1528-1541, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33052611

RESUMO

OBJECTIVES: Due to a worldwide increase in drug consumption, oral healthcare professionals are frequently confronted with patients using one or more drugs. A large number of drugs can be accompanied with adverse drug reactions in the orofacial region, amongst others of the tongue. This paper aims to give an overview of drugs that are known to be accompanied with tongue disorders. MATERIALS AND METHODS: The national drug information database for Dutch pharmacists, composed of scientific drug information, guidelines and summaries of product characteristics, was analysed for drug-induced tongue disorders. "MedDRA classification" and "Anatomical Therapeutic Chemical codes" were used to categorize the disorders. RESULTS: The database comprises of 1645 drugs of which 121 (7.4%) are documented to be accompanied with tongue disorders as an adverse effect. Drug-induced tongue disorders are predominantly observed in the following drug categories: "nervous systems," "anti-infectives for systemic use" and "alimentary tract and metabolism". The most common drug-induced tongue disorders are glossitis, tongue oedema, tongue discoloration and burning tongue. CONCLUSION: Healthcare professionals are frequently confronted with drugs that can cause tongue disorders. The overview of drugs reported in this article supports clinicians in their awareness, diagnosis and treatment of drug-induced tongue disorders.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Preparações Farmacêuticas , Bases de Dados Factuais , Bases de Dados de Produtos Farmacêuticos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Humanos , Língua
4.
Clin Cancer Res ; 26(19): 5062-5067, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32295834

RESUMO

On September 17, 2019, FDA granted accelerated approval to pembrolizumab plus lenvatinib for the treatment of patients with advanced endometrial carcinoma that is not microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR) and who have disease progression following prior systemic therapy but are not candidates for curative surgery or radiation. The submission and review of this application was conducted through an FDA Oncology Center of Excellence initiative named Project Orbis whereby the FDA, the Australian Therapeutic Goods Administration, and Health Canada were able to simultaneously review and collaborate, rendering simultaneous approval decisions in all countries. Accelerated approval of the pembrolizumab plus lenvatinib combination was based on a single-arm trial of 94 patients, with previously treated metastatic endometrial cancer whose tumors were not MSI-H/dMMR. Efficacy was demonstrated on the basis of an objective response rate of 38.3% (95% confidence interval, 28.5%-48.9%) with 10 complete responses (10.6%) accompanied by supportive durations of response. Trials to confirm clinical benefit of this combination are ongoing. Here, we summarize the benefit-risk analysis supporting accelerated approval of the pembrolizumab plus lenvatinib combination and describe the methodology for the first Project Orbis review.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Neoplasias do Endométrio/tratamento farmacológico , Compostos de Fenilureia/uso terapêutico , Quinolinas/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Austrália/epidemiologia , Canadá/epidemiologia , Aprovação de Drogas , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Feminino , Humanos , Instabilidade de Microssatélites , Estados Unidos , United States Food and Drug Administration
5.
J Exp Biol ; 222(Pt 22)2019 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-31672726

RESUMO

Despite the importance of intraoral food transport and swallowing, relatively few studies have examined the biomechanics of these behaviors in non-tetrapods, which lack a muscular tongue. Studies show that elasmobranch and teleost fishes generate water currents as a 'hydrodynamic tongue' that presumably transports food towards and into the esophagus. However, it remains largely unknown how specific musculoskeletal motions during transport correspond to food motion. Previous studies of white-spotted bamboo sharks (Chiloscyllium plagiosum) hypothesized that motions of the hyoid, branchial arches and pectoral girdle, generate caudal motion of the food through the long oropharynx of modern sharks. To test these hypotheses, we measured food and cartilage motion with XROMM during intra-oropharyngeal transport and swallowing (N=3 individuals, 2-3 trials per individual). After entering the mouth, food does not move smoothly toward the esophagus, but rather moves in distinct steps with relatively little retrograde motion. Caudal food motion coincides with hyoid elevation and a closed mouth, supporting earlier studies showing that hyoid motion contributes to intra-oropharyngeal food transport by creating caudally directed water currents. Little correspondence between pectoral girdle and food motion was found, indicating minimal contribution of pectoral girdle motion. Transport speed was fast as food entered the mouth, slower and step-wise through the pharyngeal region and then fast again as it entered the esophagus. The food's static periods in the step-wise motion and its high velocity during swallowing could not be explained by hyoid or girdle motion, suggesting these sharks may also use the branchial arches for intra-oropharyngeal transport and swallowing.


Assuntos
Deglutição/fisiologia , Orofaringe/fisiologia , Tubarões/fisiologia , Animais , Fenômenos Biomecânicos , Região Branquial , Alimentos , Hidrodinâmica , Osso Hioide , Movimento , Tubarões/anatomia & histologia
6.
J Exp Biol ; 222(Pt 5)2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30824570

RESUMO

White-spotted bamboo sharks, Chiloscyllium plagiosum, generate strong suction-feeding pressures that rival the highest levels measured in ray-finned fishes. However, the hyostylic jaw suspension of these sharks is fundamentally different from the actinopterygian mechanism, including more mobile hyomandibulae, with the jaws and ceratohyal suspended from the hyomandibulae. Prior studies have proposed skeletal kinematics during feeding in orectolobid sharks from indirect measurements. Here, we tested these hypotheses using XROMM to measure cartilage motions directly. In agreement with prior hypotheses, we found extremely large retraction and depression of the ceratohyal, facilitated by large protraction and depression of the hyomandibula. Somewhat unexpectedly, XROMM also showed tremendous long-axis rotation (LAR) of both the ceratohyal and hyomandibula. This LAR likely increases the range of motion for the hyoid arch by keeping the elements properly articulated through their large arcs of motion. XROMM also confirmed that upper jaw protraction occurs before peak gape, similarly to actinopterygian suction feeders, but different from most other sharks in which jaw protrusion serves primarily to close the mouth. Early jaw protraction results from decoupling the rotations of the hyomandibula, with much of protraction occurring before peak gape with the other rotations lagging behind. In addition, the magnitudes of retraction and protraction of the hyoid elements are independent of the magnitude of depression, varying the shape of the mouth among feeding strikes. Hence, the large variation in suction-feeding behavior and performance may contribute to the wide dietary breadth of bamboo sharks.


Assuntos
Região Branquial/fisiologia , Arcada Osseodentária/fisiologia , Boca/fisiologia , Comportamento Predatório , Tubarões/fisiologia , Animais , Fenômenos Biomecânicos , Sucção
7.
Proc Biol Sci ; 284(1859)2017 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-28724735

RESUMO

Positioned at the intersection of the head, body and forelimb, the pectoral girdle has the potential to function in both feeding and locomotor behaviours-although the latter has been studied far more. In ray-finned fishes, the pectoral girdle attaches directly to the skull and is retracted during suction feeding, enabling the ventral body muscles to power rapid mouth expansion. However, in sharks, the pectoral girdle is displaced caudally and entirely separate from the skull (as in tetrapods), raising the question of whether it is mobile during suction feeding and contributing to suction expansion. We measured three-dimensional kinematics of the pectoral girdle in white-spotted bamboo sharks during suction feeding with X-ray reconstruction of moving morphology, and found the pectoral girdle consistently retracted about 11° by rotating caudoventrally about the dorsal scapular processes. This motion occurred mostly after peak gape, so it likely contributed more to accelerating captured prey through the oral cavity and pharynx, than to prey capture as in ray-finned fishes. Our results emphasize the multiple roles of the pectoral girdle in feeding and locomotion, both of which should be considered in studying the functional and evolutionary morphology of this structure.


Assuntos
Comportamento Alimentar/fisiologia , Locomoção , Tubarões/anatomia & histologia , Estruturas Animais/anatomia & histologia , Estruturas Animais/fisiologia , Animais , Fenômenos Biomecânicos , Boca , Tubarões/fisiologia , Crânio
8.
ACS Infect Dis ; 3(7): 462-466, 2017 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-28350438

RESUMO

The lipopeptide antibiotic daptomycin is active against Gram-positive pathogens. It permeabilizes bacterial cell membranes, which involves the formation of membrane-associated oligomers. We here studied a dimer of daptomycin whose two subunits were linked through a bivalent aliphatic acyl chain. Unexpectedly, the dimer had very low activity on vegetative Staphylococcus aureus and Bacillus subtilis cells. However, activity resembled that of monomeric daptomycin on liposomes and on B. subtilis L-forms. These findings underscore the importance of the bacterial cell wall in daptomycin resistance.


Assuntos
Antibacterianos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Daptomicina/farmacologia , Farmacorresistência Bacteriana/fisiologia , Staphylococcus aureus/efeitos dos fármacos , Acilação , Antibacterianos/síntese química , Antibacterianos/metabolismo , Bacillus subtilis/crescimento & desenvolvimento , Bacillus subtilis/metabolismo , Transporte Biológico , Parede Celular/química , Parede Celular/metabolismo , Daptomicina/síntese química , Daptomicina/metabolismo , Ácidos Dicarboxílicos/química , Dimerização , Lipossomos/química , Testes de Sensibilidade Microbiana , Permeabilidade , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus aureus/metabolismo , Ácidos Esteáricos/química
9.
Med Phys ; 44(4): 1545-1551, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28094855

RESUMO

PURPOSE: In this work, we develop a methodology for using Fricke gel dosimeters for dose distribution measurements surrounding high-density implants which circumvents artifact production by removing the obstruction during imaging. METHODS: Custom 3D printed molds were used to set cavities in Fricke gel phantoms to allow for the suspension of high-density implants in different geometries. This allowed for the metal valve extracted from a temporary tissue expander to be suspended during irradiation, and removed during optical-CT scanning. RESULTS: The removal of the metal implant and subsequent backfilling of the remaining cavity with optically matched fluid prior to dose evaluation enables accurate optical-CT scanning of the gel dosimeters. Results have shown very good agreement between measured and calculated doses within 2 mm from the surface of the implant. Slight deviations are present within 1 mm of the interface. CONCLUSIONS: Artifacts in the form of radial streaking, cold spots, and hot spots were all reduced using this technique, enabling the broader and more accurate use of optical-CT for the imaging of gels containing opaque objects.


Assuntos
Próteses e Implantes , Dosímetros de Radiação , Artefatos , Géis , Fenômenos Ópticos , Imagens de Fantasmas , Impressão Tridimensional , Tomografia Computadorizada por Raios X
10.
ISME J ; 11(5): 1158-1167, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28072418

RESUMO

Understanding how microbial communities respond and adjust to ecosystem perturbation is often difficult to interpret due to multiple and often simultaneous variations in observed conditions. In this research, we investigated the microbial community dynamics of Inferno Crater Lake, an acidic geothermal spring in New Zealand with a unique thermal cycle that varies between 30 and 80 °C over a period of 40-60 days. Using a combination of next-generation sequencing, geochemical analysis and quantitative PCR we found that the microbial community composition was predominantly chemolithotrophic and strongly associated with the thermal cycle. At temperatures >65 °C, the microbial community was dominated almost exclusively by sulphur-oxidising archaea (Sulfolobus-like spp.). By contrast, at mesophilic temperatures the community structure was more mixed, comprising both archaea and bacteria but dominated primarily by chemolithotrophic sulphur and hydrogen oxidisers. Multivariate analysis of physicochemical data confirmed that temperature was the only significant variable associated with community turnover. This research contributes to our understanding of microbial community dynamics in variable environments, using a naturally alternating system as a model and extends our limited knowledge of acidophile ecology in geothermal habitats.


Assuntos
Archaea/isolamento & purificação , Bactérias/isolamento & purificação , Fontes Termais/microbiologia , Archaea/genética , Archaea/metabolismo , Bactérias/genética , Bactérias/metabolismo , Crescimento Quimioautotrófico , Ecossistema , Temperatura Alta , Lagos/microbiologia , Nova Zelândia , RNA Ribossômico 16S/genética , Enxofre/metabolismo , Temperatura
11.
Biochim Biophys Acta ; 1858(9): 1999-2005, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27237728

RESUMO

Daptomycin and A54145 are homologous lipopeptide antibiotics that permeabilize the cell membranes of Gram-positive bacteria. Membrane permeabilization depends on the presence of both phosphatidylglycerol (PG) and calcium, and it involves the formation of oligomeric transmembrane pores that consist of approximately 6-8 subunits. We here show that each lipopeptide molecule binds two calcium ions in separable, successive steps. The first calcium ion causes the lipopeptide molecule to bind to the target membrane, and likely to form a loosely associated oligomer. Higher calcium concentrations induce binding of a second ion, which produces the more tightly associated and more deeply membrane-inserted final, functional form of the oligomer. Both calcium-dependent steps are accompanied by fluorescence signals that indicate transition of specific amino acid residues into less polar environments, suggestive of insertion into the target membrane. Our findings agree with the earlier observation that two of the four acidic amino acid residues in the daptomycin molecule are essential for antibacterial activity.


Assuntos
Antibacterianos/química , Cálcio/química , Daptomicina/química , Lipossomos/química , Lipoproteínas/química
12.
J Org Chem ; 81(6): 2624-8, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-26938305

RESUMO

α-Azido acids have been used in solid phase peptide synthesis (SPPS) for almost 20 years. Here we report that peptides bearing an N-terminal α-azidoaspartate residue undergo elimination of an azide ion when treated with reagents that are commonly used for removing the Fmoc group during SPPS. We also report an alternative solid-phase route to the synthesis of an analog of daptomycin that uses a reduced number of α-azido amino acids and without elimination of an azide ion.


Assuntos
Aminoácidos/química , Daptomicina/síntese química , Indicadores e Reagentes/química , Peptídeos/síntese química , Aminoácidos/síntese química , Daptomicina/química , Peptídeos/química , Técnicas de Síntese em Fase Sólida
13.
J Clin Pharmacol ; 55 Suppl 3: S123-32, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24965228

RESUMO

Monoclonal antibodies have become mainstays of treatment for many diseases. After more than a decade on the Canadian market, a number of authorized monoclonal antibody products are facing patent expiry. Given their success, most notably in the areas of oncology and autoimmune disease, pharmaceutical and biotechnology companies are eager to produce their own biosimilar versions and have begun manufacturing and testing for a variety of monoclonal antibody products. In October of 2013, the first biosimilar monoclonal antibody products were approved by the European Medicines Agency (Remsima™ and Inflectra™). These products were authorized by Health Canada shortly after; however, while the EMA allowed for extrapolation to all of the indications held by the reference product, Health Canada limited extrapolation to a subset of the indications held by the reference product, Remicade®. The purpose of this review is to discuss the Canadian regulatory framework for the authorization of biosimilar mAbs with specific discussion around the clinical requirements for establishing (bio)-similarity and to present the principles that are used in the clinical assessment of New Drug Submissions for intended biosimilar monoclonal antibodies. Health Canada's current views regarding indication extrapolation, product interchangeability, and post-market surveillance are discussed as well.


Assuntos
Anticorpos Monoclonais , Medicamentos Biossimilares , Aprovação de Drogas , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/farmacocinética , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Medicamentos Biossimilares/efeitos adversos , Medicamentos Biossimilares/farmacocinética , Medicamentos Biossimilares/farmacologia , Medicamentos Biossimilares/uso terapêutico , Canadá , Humanos , Vigilância de Produtos Comercializados , Equivalência Terapêutica
14.
Matern Child Nutr ; 8(1): 115-29, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22136223

RESUMO

Poor complementary feeding practices and low-quality complementary foods are significant causes of growth faltering and child mortality throughout the developing world. Ready-to-use foods (RUF) are energy-dense, lipid-based products that do not require cooking or refrigeration that have been used to prevent and treat malnutrition among vulnerable children. The effectiveness of these products in improving child nutritional status depends on household use by caregivers. To identify the key facilitators and barriers that influence appropriate in-home RUF consumption by supplemental feeding program beneficiaries, we conducted individual interviews among caregivers (n = 80), RUF producers (n = 8) and program staff (n = 10) involved in the Byokulia Bisemeye mu Bantu supplemental feeding program in Bundibugyo, Uganda. By documenting caregiver perceptions and feeding practices related to RUF, we developed a conceptual framework of factors that affect appropriate feeding with RUF. Findings suggest that locally produced RUF is well received by caregivers and children, and is perceived by caregivers and the community to be a healthy supplemental food for malnourished children. However, child feeding practices, including sharing of RUF within households, compromise the nutrient delivery to the intended child. Interventions and educational messages informed by this study can help to improve RUF delivery to targeted beneficiaries.


Assuntos
Cuidadores/psicologia , Barreiras de Comunicação , Alimentos Formulados , Facilitação Social , Magreza/prevenção & controle , Pré-Escolar , Gorduras na Dieta/administração & dosagem , Feminino , Humanos , Lactente , Masculino , Desnutrição/prevenção & controle , Desnutrição/terapia , Estado Nutricional , Valor Nutritivo , Magreza/terapia , Uganda , Populações Vulneráveis , Desmame
15.
ACS Nano ; 5(7): 5579-93, 2011 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-21692444

RESUMO

Effective biological application of nanocrystalline semiconductor quantum dots continues to be hampered by the lack of easily implemented and widely applicable labeling chemistries. Here, we introduce two new orthogonal nanocrystal bioconjugation chemistries that overcome many of the labeling issues associated with currently utilized approaches. These chemistries specifically target either (1) the ubiquitous amines found on proteins or (2) thiols present in either antibody hinge regions or recombinantly introduced into other proteins to facilitate site-specific labeling. The amine chemistry incorporates aniline-catalyzed hydrazone bond formation, while the sulfhydryl chemistry utilizes nanocrystals displaying surface activated maleimide groups. Both reactive chemistries are rapidly implemented, yielding purified nanocrystal-protein bioconjugates in as little as 3 h. Following initial characterization of the nanocrystal materials, the wide applicability and strong multiplexing potential of these chemistries are demonstrated in an array of applications including immunoassays, immunolabeling in both cellular and tissue samples, in vivo cellular uptake, and flow cytometry. Side-by-side comparison of the immunolabeled cells suggested a functional equivalence between results generated with the amine and thiol-labeled antibody-nanocrystal bioconjugates in that format. Three-color labeling was achieved in the cellular uptake format, with no significant toxicity observed while simultaneous five-color labeling of different epitopes was demonstrated for the immunolabeled tissue sample. Novel labeling applications are also facilitated by these chemistries, as highlighted by the ability to directly label cellular membranes in adherent cell cultures with the thiol-reactive chemistry.


Assuntos
Pontos Quânticos , Semicondutores , Coloração e Rotulagem/métodos , Aminas/química , Animais , Transporte Biológico , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Sobrevivência Celular , Cor , Enterotoxinas/análise , Citometria de Fluxo , Humanos , Imunoensaio , Imuno-Histoquímica , Especificidade por Substrato , Compostos de Sulfidrila/química
16.
Nutr Cancer ; 63(1): 109-20, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21161819

RESUMO

Diets rich in fruits and vegetables have been shown to improve patient prognosis in a variety of cancers, a benefit partly derived from phytochemicals, many of which target cell death pathways in tumor cells. Cranberries (Vaccinium macrocarpon) are a phytochemical-rich fruit containing a variety of polyphenolic compounds. As flavonoids have been shown to induce apoptosis in human tumor cells, this study investigated the hypothesis that cranberry-mediated cytotoxicity in DU145 human prostate adenocarcinoma cells involves apoptosis. The results showed that induction of apoptosis in these cells occurred in response to treatment with whole cranberry extract and occurred through caspase-8 mediated cleavage of Bid protein to truncated Bid resulting in cytochrome-C release from the mitochondria. Subsequent activation of caspase-9 ultimately resulted in cell death as characterized by DNA fragmentation. Increased Par-4 protein expression was observed, and this is suggested to be at least partly responsible for caspase-8 activation. Proanthocyanidin-enriched and flavonol-enriched fractions of cranberry also increased caspase-8 and caspase-9 activity, suggesting that these compounds play a possible role in apoptosis induction. These findings indicate that cranberry phytochemicals can induce apoptosis in prostate cancer cells in vitro, and these findings further establish the potential value of cranberry phytochemicals as possible agents against prostate cancer.


Assuntos
Apoptose/efeitos dos fármacos , Extratos Vegetais/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Vaccinium macrocarpon , Caspase 8/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Fragmentação do DNA/efeitos dos fármacos , Flavonoides/análise , Humanos , Masculino , Neoplasias da Próstata/patologia , Vaccinium macrocarpon/química
17.
Int J Cancer ; 125(5): 1193-204, 2009 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-19444912

RESUMO

Cisplatin is one of the most widely used chemotherapeutics in the world today. Unfortunately, chemoresistance often develops hindering the effectiveness of the drug. Mismatch-repair (MMR) and p53 have previously been shown to be important determinants of cisplatin resistance and can contribute to cisplatin resistance clinically. Here, we have used cDNA microarray to identify several genes as up or downregulated in a previously described, cisplatin resistant, clone of the HCT116 cell line (HCT116-K). On follow-up, one gene, APM2, was found to promote cisplatin resistance when overexpressed in sensitive HCT116 clones. Furthermore, silencing APM2 in a panel of cell lines encompassing all combinations of p53 status and MMR proficiency (HCT116-K, HCT116, SW620, MCF7, PC-3 and OV2008) resulted in sensitization regardless of these 2 factors. In addition, silencing APM2 stably using shRNA also resulted in the sensitization of cells to cisplatin. More importantly, cisplatin inhibited the growth of APM2 silenced tumor xenografts (HCT116-K or OV2008 cells) significantly better than it inhibited the growth of xenografts carrying nontargeting control shRNAs. These findings represent a novel strategy that could be exploited to overcome cisplatin resistance in patients regardless of p53 status or ability to perform MMR.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Reparo de Erro de Pareamento de DNA/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Neoplasias/tratamento farmacológico , Proteína Supressora de Tumor p53/metabolismo , Adiponectina/antagonistas & inibidores , Adiponectina/genética , Adiponectina/metabolismo , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Western Blotting , Proliferação de Células/efeitos dos fármacos , Ensaio de Unidades Formadoras de Colônias , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Perfilação da Expressão Gênica , Humanos , Camundongos , Camundongos Nus , Neoplasias/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia , Tolerância a Radiação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína Supressora de Tumor p53/genética , Raios X , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Int J Oncol ; 30(6): 1369-80, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17487357

RESUMO

We previously isolated several clones that were closely-related genetically from a human colorectal tumor (HCT116) cell line. These clones displayed significantly different X-radiation response phenotypes. In this paper, we investigated how a single dose of X-radiation modulated the transcriptomic profiles of either the radiation-resistant (HCT116Clone2_XRR) or the radiation-sensitive (HCT116CloneK_XRS) clone when each was compared to a reference clone, HCT116Clone10_control. The latter represented a control clone that displayed a similar X-radiation response as the parental HCT116 cells. Pooled RNAs were obtained from HCT116Clone2_XRR, HCT116CloneK_XRS or HCT116Clone10_control cells either before or at 10 min, 6 or 24 h after treatment with 4-Gy X-radiation. Transcriptomic profiles were assessed by cDNA microarrays. At least three independent experiments were carried out for each time point and statistical analysis was performed by paired t-test (p<0.05). From 19,200 genes/ESTs examined, we identified only 120 genes/ESTs that were differentially expressed at any one of these four time points. Interestingly, different patterns of gene modulation were observed between the radiation-sensitive and radiation-resistant clones. However, the fold changes of gene modulation were generally small (2-3 fold). Surprisingly, only 12.7% of 79 genes involved in DNA damage sensor/repair and cell cycle and between 2.6 and 9.2% of 76 genes involved in apoptosis, were significantly modulated in these early time points following irradiation. By comparison, up to 10% of 40 known housekeeping genes were differentially expressed. Thus in our experimental model, we were able to detect the up-regulation or down-regulation of mostly novel genes and/or pathways in the acute period (up to 24 h) following a single dose of 4-Gy X-radiation.


Assuntos
Neoplasias Colorretais/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos da radiação , Tolerância a Radiação/genética , Western Blotting , Linhagem Celular Tumoral , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Raios X
19.
PDA J Pharm Sci Technol ; 60(1): 17-53, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17089677

RESUMO

Process analytical technology (PAT) refers to a series of tools used to ensure that quality is built into products while at the same time improving the understanding of processes, increasing efficiency, and decreasing costs. It has not been widely adopted by the pharmaceutical industry. As the setting for this paper, the current pharmaceutical manufacturing paradigm and PAT guidance to date are discussed prior to the review of PAT principles and tools, benefits, and challenges. The PAT toolkit contains process analyzers, multivariate analysis tools, process control tools, and continuous improvement/knowledge management/information technology systems. The integration and implementation of these tools is complex, and has resulted in uncertainty with respect to both regulation and validation. The paucity of staff knowledgeable in this area may complicate adoption. Studies to quantitate the benefits resulting from the adoption of PAT within the pharmaceutical industry would be a valuable addition to the qualitative studies that are currently available.


Assuntos
Indústria Farmacêutica/tendências , Integração de Sistemas , Tecnologia Farmacêutica/normas , Interpretação Estatística de Dados , Indústria Farmacêutica/legislação & jurisprudência , Fidelidade a Diretrizes , Guias como Assunto , Análise Multivariada , Preparações Farmacêuticas/química , Controle de Qualidade , Reprodutibilidade dos Testes , Tecnologia Farmacêutica/economia , Tecnologia Farmacêutica/métodos , Fatores de Tempo , Estados Unidos , United States Food and Drug Administration/legislação & jurisprudência
20.
Mol Genet Metab ; 89(1-2): 58-63, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16876451

RESUMO

Exercise induced rhabdomyolysis is a complication of long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) and mitochondrial trifunctional protein (TFP) deficiency that frequently leads to exercise avoidance. Dietary therapy for most subjects includes medium-chain triglyceride (MCT) supplementation but analysis of diet records indicates that the majority of patients consume oral MCT only with breakfast and at bedtime. We hypothesized that MCT immediately prior to exercise would provide an alternative fuel source during that bout of exercise and improve exercise tolerance in children with LCHAD deficiency. Nine subjects completed two 45 min moderate intensity (60-70% predicted maximum heart rate (HR)) treadmill exercise tests. Subjects were given 4 oz of orange juice alone or orange juice and 0.5 g MCT per kg lean body mass, 20 min prior to exercise in a randomized cross-over design. ECG and respiratory gas exchange including respiratory quotient (RQ) were monitored. Blood levels of acylcarnitines, creatine kinase, lactate, and beta-hydroxybutyrate were measured prior to and immediately after exercise, and again following 20 min rest. Creatine kinase and lactate levels did not change with exercise. There was no significant difference in RQ between the two exercise tests but there was a decrease in steady-state HR following MCT supplementation. Cumulative long-chain 3-hydroxyacylcarnitines were 30% lower and beta-hydroxybutyrate was three-fold higher after the MCT-pretreated exercise test compared to the test with orange juice alone. Coordinating MCT supplementation with periods of increased activity may improve the metabolic control of children with LCHAD and TFP deficiency following exercise.


Assuntos
3-Hidroxiacil-CoA Desidrogenases/deficiência , Exercício Físico , Complexos Multienzimáticos/deficiência , Rabdomiólise/enzimologia , Triglicerídeos/metabolismo , Ácido 3-Hidroxibutírico/sangue , Adolescente , Carnitina/análogos & derivados , Carnitina/sangue , Criança , Creatina Quinase/sangue , Feminino , Humanos , Ácido Láctico/sangue , 3-Hidroxiacil-CoA Desidrogenase de Cadeia Longa , Masculino , Proteína Mitocondrial Trifuncional , Triglicerídeos/administração & dosagem
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