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1.
Cytometry A ; 93(1): 137-148, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28678404

RESUMO

Pluripotent stem cells have the capacity to grow indefinitely in culture and differentiate into derivatives of the three germ layers. These properties underpin their potential to be used in regenerative medicine. Originally derived from early embryos, pluripotent stem cells can now be derived by reprogramming an adult cell back to a pluripotent state. Companion animals such as horses, dogs, and cats suffer from many injuries and diseases for which regenerative medicine may offer new treatments. As many of the injuries and diseases are similar to conditions in humans the use of companion animals for the experimental and clinical testing of stem cell and regenerative medicine products would provide relevant animal models for the translation of therapies to the human field. In order to fully utilize companion animal pluripotent stem cells robust, standardized methods of characterization must be developed to ensure that safe and effective treatments can be delivered. In this review we discuss the methods that are available for characterizing pluripotent stem cells and the techniques that have been applied in cells from companion animals. We describe characteristics which have been described consistently across reports as well as highlighting discrepant results. Significant steps have been made to define the in vitro culture requirements and drive lineage specific differentiation of pluripotent stem cells in companion animal species. However, additional basic research to compare pluripotent stem cell types and define characteristics of pluripotency in companion animal species is still required. © 2017 International Society for Advancement of Cytometry.


Assuntos
Animais de Estimação , Células-Tronco Pluripotentes/citologia , Animais , Gatos , Técnicas de Cultura de Células/métodos , Técnicas de Cultura de Células/veterinária , Diferenciação Celular , Linhagem da Célula , Modelos Animais de Doenças , Cães , Células-Tronco Embrionárias/citologia , Cavalos , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Modelos Animais , Medicina Regenerativa , Pesquisa Translacional Biomédica
2.
Phytopathology ; 106(4): 320-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26714102

RESUMO

Oomycetes from the genus Phytophthora are among the most important plant pathogens in agriculture. Epidemics caused by P. infestans precipitated the great Irish famine and had a major impact on society and human history. In the tropics, P. palmivora is a pathogen of many plant species including cacao (Theobroma cacao), citrus (Citrus sp.), durian (Durio zibethines), jackfruit (Artrocarpus heterophyllus), rubber (Hevea brasiliensis), and several palm species including coconut (Cocos nucifera), and the African oil palm (Elaeis guineensis) as determined recently. The first localized epidemics of bud rot in oil palm in Colombia were reported in 1964. However, recent epidemics of bud rot have destroyed more than 70,000 ha of oil palm in the Western and Central oil palm growing regions of Colombia. The agricultural, social, and economic implications of these outbreaks have been significant in Colombia. Identification of the pathogen after 100 years of investigating the disease in the world enabled further understanding of infection, expression of a range of symptoms, and epidemiology of the disease. This review examines the identification of P. palmivora as the cause of bud rot in Colombia, its epidemiology, and discusses the importance of P. palmivora as a major threat to oil palm plantings globally.


Assuntos
Arecaceae/microbiologia , Phytophthora/isolamento & purificação , Doenças das Plantas/microbiologia , Colômbia , Geografia , Phytophthora/fisiologia , Doenças das Plantas/prevenção & controle , Doenças das Plantas/estatística & dados numéricos
3.
Reprod Domest Anim ; 50(4): 669-76, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26074059

RESUMO

Dogs and humans have many inherited genetic diseases in common and conditions that are increasingly prevalent in humans also occur naturally in dogs. The use of dogs for the experimental and clinical testing of stem cell and regenerative medicine products would benefit canine health and welfare and provide relevant animal models for the translation of therapies to the human field. Induced pluripotent stem cells (iPSCs) have the capacity to turn into all cells of the body and therefore have the potential to provide cells for therapeutic use and for disease modelling. The objective of this study was to derive and characterize iPSCs from karyotypically abnormal adult canine cells. Aneuploid adipose-derived mesenchymal stromal cells (AdMSCs) from an adult female Weimeraner were re-programmed into iPSCs via overexpression of four human pluripotency factors (Oct 4, Sox2, Klf4 and c-myc) using retroviral vectors. The iPSCs showed similarity to human ESCs with regard to morphology, pluripotency marker expression and the ability to differentiate into derivatives of all three germ layers in vitro (endoderm, ectoderm and mesoderm). The iPSCs also demonstrated silencing of the viral transgenes and re-activation of the silent X chromosome, suggesting full reprogramming had occurred. The levels of aneuploidy observed in the AdMSCs were maintained in the iPSCs. This finding demonstrates the potential for generating canine induced pluripotent stem cells for use as disease models in addition to regenerative medicine and pharmaceutical testing.


Assuntos
Cães , Células-Tronco Pluripotentes Induzidas/fisiologia , Tecido Adiposo/citologia , Animais , Biomarcadores/análise , Diferenciação Celular/fisiologia , Reprogramação Celular , Feminino , Expressão Gênica , Vetores Genéticos , Humanos , Imuno-Histoquímica , Células-Tronco Pluripotentes Induzidas/citologia , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Células-Tronco Mesenquimais/metabolismo , Modelos Animais , Fator 3 de Transcrição de Octâmero/genética , Proteínas Proto-Oncogênicas c-myc/genética , Fatores de Transcrição SOXB1/genética , Transfecção/veterinária
4.
Persoonia ; 35: 264-327, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26823636

RESUMO

Novel species of fungi described in the present study include the following from Australia: Neoseptorioides eucalypti gen. & sp. nov. from Eucalyptus radiata leaves, Phytophthora gondwanensis from soil, Diaporthe tulliensis from rotted stem ends of Theobroma cacao fruit, Diaporthe vawdreyi from fruit rot of Psidium guajava, Magnaporthiopsis agrostidis from rotted roots of Agrostis stolonifera and Semifissispora natalis from Eucalyptus leaf litter. Furthermore, Neopestalotiopsis egyptiaca is described from Mangifera indica leaves (Egypt), Roussoella mexicana from Coffea arabica leaves (Mexico), Calonectria monticola from soil (Thailand), Hygrocybe jackmanii from littoral sand dunes (Canada), Lindgomyces madisonensis from submerged decorticated wood (USA), Neofabraea brasiliensis from Malus domestica (Brazil), Geastrum diosiae from litter (Argentina), Ganoderma wiiroense on angiosperms (Ghana), Arthrinium gutiae from the gut of a grasshopper (India), Pyrenochaeta telephoni from the screen of a mobile phone (India) and Xenoleptographium phialoconidium gen. & sp. nov. on exposed xylem tissues of Gmelina arborea (Indonesia). Several novelties are introduced from Spain, namely Psathyrella complutensis on loamy soil, Chlorophyllum lusitanicum on nitrified grasslands (incl. Chlorophyllum arizonicum comb. nov.), Aspergillus citocrescens from cave sediment and Lotinia verna gen. & sp. nov. from muddy soil. Novel foliicolous taxa from South Africa include Phyllosticta carissicola from Carissa macrocarpa, Pseudopyricularia hagahagae from Cyperaceae and Zeloasperisporium searsiae from Searsia chirindensis. Furthermore, Neophaeococcomyces is introduced as a novel genus, with two new combinations, N. aloes and N. catenatus. Several foliicolous novelties are recorded from La Réunion, France, namely Ochroconis pandanicola from Pandanus utilis, Neosulcatispora agaves gen. & sp. nov. from Agave vera-cruz, Pilidium eucalyptorum from Eucalyptus robusta, Strelitziana syzygii from Syzygium jambos (incl. Strelitzianaceae fam. nov.) and Pseudobeltrania ocoteae from Ocotea obtusata (Beltraniaceae emend.). Morphological and culture characteristics along with ITS DNA barcodes are provided for all taxa.

5.
Eur J Cancer Care (Engl) ; 22(1): 51-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22672363

RESUMO

Little is known about the contribution of diet components independent of body composition to persistent fatigue in breast cancer survivors. Therefore, our study aim was to determine the associations among dietary intake and fatigue in relation to and independent of adiposity and physical activity (PA) in breast cancer survivors. Baseline data from 42 breast cancer survivors enrolled in a randomised exercise trial were analysed: fatigue (Functional Assessment of Cancer Therapy for fatigue), diet components (3-day diet record), body mass index, per cent body fat (dual-energy X-ray absorptiometry) and PA (accelerometer). The mean age was 54 ± 9 years with an average body mass index of 30.5 ± 8.1 kg/m(2). Fatigue was positively associated with % of kcal/day fat intake (r = 0.31, P < 0.05) and inversely related to fibre g/day (r = 0.38, P < 0.05) and carbohydrate g/day intake (r = 0.31, P < 0.05). Mean fatigue was greater for participants eating <25 g/day of fibre compared with >25 g/day of fibre (15.7 ± 10.8 versus 6.4 ± 3.7, P < 0.005). No significant associations were noted between fatigue and PA or body composition. Diets high in fibre and low in fat are associated with reduced fatigue in breast cancer survivors. The difference in fatigue for low- versus high-fibre diets exceeded the minimal clinically important difference of three units. Prospective studies evaluating the effect of changing diet on fatigue in breast cancer survivors are warranted.


Assuntos
Neoplasias da Mama/complicações , Dieta , Fadiga/etiologia , Adiposidade , Idoso , Composição Corporal/fisiologia , Índice de Massa Corporal , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Fibras na Dieta/administração & dosagem , Ingestão de Energia/fisiologia , Exercício Físico , Fadiga/fisiopatologia , Feminino , Humanos , Pessoa de Meia-Idade , Sobreviventes
6.
Radiat Environ Biophys ; 52(4): 513-21, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23963461

RESUMO

A "broadbeam" facility is demonstrated for the vertical microbeam at Surrey's Ion Beam Centre, validating the new technique used by Barazzuol et al. (Radiat Res 177:651-662, 2012). Here, droplets with a diameter of about 4 mm of 15,000 mammalian cells in suspension were pipetted onto defined locations on a 42-mm-diameter cell dish with each droplet individually irradiated in "broadbeam" mode with 2 MeV protons and 4 MeV alpha particles and assayed for clonogenicity. This method enables multiple experimental data points to be rapidly collected from the same cell dish. Initially, the Surrey vertical beamline was designed for the targeted irradiation of single cells with single counted ions. Here, the benefits of both targeted single-cell and broadbeam irradiations being available at the same facility are discussed: in particular, high-throughput cell irradiation experiments can be conducted on the same system as time-intensive focused-beam experiments with the added benefits of fluorescent microscopy, cell recognition and time-lapse capabilities. The limitations of the system based on a 2 MV tandem accelerator are also discussed, including the uncertainties associated with particle Poisson counting statistics, spread of linear energy transfer in the nucleus and a timed dose delivery. These uncertainties are calculated with Monte Carlo methods. An analysis of how this uncertainty affects relative biological effect measurements is made and discussed.


Assuntos
Radiobiologia/métodos , Animais , Linhagem Celular , Cricetinae , Cricetulus , Relação Dose-Resposta à Radiação , Transferência Linear de Energia , Método de Monte Carlo , Radiobiologia/instrumentação
7.
Equine Vet J ; 42(7): 636-42, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20840579

RESUMO

REASONS FOR PERFORMING STUDY: Injury to the superficial digital flexor tendon (SDFT) is common in racing and sport horses and poor tendon regeneration leads to high reinjury rates. Autologous mesenchymal stromal cells (MSCs) are being used clinically to improve tendon regeneration but they have some practical limitations. Embryonic stem cells (ESCs) may overcome these limitations but their fate following injection into the damaged SDFT is unknown. OBJECTIVE: To inject MSCs and ESCs into distinct areas of damage in the SDFT and monitor their survival over a 3 month period. METHODS: MSCs and ESCs expressing different reporter genes were injected into separate sites of mechanically induced damage in SDFTs. Cell survival and distribution were examined post mortem after 10, 30, 60 and 90 days and host immune responses determined. RESULTS: Neither MSCs nor ESCs produced signs of cell-mediated immune response or tumour formation. ESC survival was high and numbers were maintained at a constant level over 90 days. ESCs were present at all sites of damage. In contrast, MSCs showed <5% survival at 10 days and numbers declined over the course of the experiment. MSCs were detected only at the site into which they were injected. CONCLUSIONS: ESCs survived in greater numbers than MSCs in the damaged tendon and did not induce an immune response, or form tumours at the injection sites in the 90 day time period studied. ESCs also demonstrated an ability to migrate to other areas of damage within the same tendon, whereas MSCs did not. POTENTIAL RELEVANCE: ESCs can be used allogeneically, therefore providing a possible 'off the shelf' source of cells for therapeutic use which overcomes the practical limitations of autologous MSCs. Furthermore, MSCs and ESCs have different survival rates and migration patterns in the damaged tendon, suggesting that they may produce different functional effects. This may have clinical relevance to treating tendon injuries in the horse.


Assuntos
Células-Tronco Embrionárias/transplante , Doenças dos Cavalos/terapia , Transplante de Células-Tronco Mesenquimais/veterinária , Células-Tronco Mesenquimais/citologia , Traumatismos dos Tendões/veterinária , Animais , Células-Tronco Embrionárias/citologia , Cavalos , Traumatismos dos Tendões/terapia
8.
Mech Dev ; 163: 103635, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32795590

RESUMO

The transcription factor scleraxis (SCX) is expressed throughout tendon development and plays a key role in directing tendon wound healing. However, little is known regarding its role in fetal or young postnatal tendons, stages in development that are known for their enhanced regenerative capabilities. Here we used RNA-sequencing to compare the transcriptome of adult and fetal tenocytes following SCX knockdown. SCX knockdown had a larger effect on gene expression in fetal tenocytes, affecting 477 genes in comparison to the 183 genes affected in adult tenocytes, indicating that scleraxis-dependent processes may differ in these two developmental stages. Gene ontology, network and pathway analysis revealed an overrepresentation of extracellular matrix (ECM) remodelling processes within both comparisons. These included several matrix metalloproteinases, proteoglycans and collagens, some of which were also investigated in SCX knockdown tenocytes from young postnatal foals. Using chromatin immunoprecipitation, we also identified novel genes that SCX differentially interacts with in adult and fetal tenocytes. These results indicate a role for SCX in modulating ECM synthesis and breakdown and provide a useful dataset for further study into SCX gene regulation.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Matriz Extracelular/genética , Traumatismos dos Tendões/genética , Fatores de Transcrição/genética , Transcriptoma/genética , Animais , Colágeno/genética , Regulação da Expressão Gênica/genética , Cavalos/genética , Cavalos/crescimento & desenvolvimento , RNA Mensageiro/genética , RNA-Seq , Traumatismos dos Tendões/patologia , Tendões/crescimento & desenvolvimento , Tendões/patologia , Tenócitos/metabolismo , Tenócitos/patologia , Cicatrização/genética
9.
Stem Cell Res Ther ; 11(1): 184, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32430075

RESUMO

BACKGROUND: Tendon injuries occur frequently in human and equine athletes. Treatment options are limited, and the prognosis is often poor with functionally deficient scar tissue resulting. Fetal tendon injuries in contrast are capable of healing without forming scar tissue. Embryonic stem cells (ESCs) may provide a potential cellular therapeutic to improve adult tendon regeneration; however, whether they can mimic the properties of fetal tenocytes is unknown. To this end, understanding the unique expression profile of normal adult and fetal tenocytes is crucial to allow validation of ESC-derived tenocytes as a cellular therapeutic. METHODS: Equine adult, fetal and ESC-derived tenocytes were cultured in a three-dimensional environment, with histological, morphological and transcriptomic differences compared. Additionally, the effects on gene expression of culturing adult and fetal tenocytes in either conventional two-dimensional monolayer culture or three-dimensional culture were compared using RNA sequencing. RESULTS: No qualitative differences in three-dimensional tendon constructs generated from adult, fetal and ESCs were found using histological and morphological analysis. However, genome-wide transcriptomic analysis using RNA sequencing revealed that ESC-derived tenocytes' transcriptomic profile more closely resembled fetal tenocytes as opposed to adult tenocytes. Furthermore, this study adds to the growing evidence that monolayer cultured cells' gene expression profiles converge, with adult and fetal tenocytes having only 10 significantly different genes when cultured in this manner. In contrast, when adult and fetal tenocytes were cultured in 3D, large distinctions in gene expression between these two developmental stages were found, with 542 genes being differentially expressed. CONCLUSION: The information provided in this study makes a significant contribution to the investigation into the differences between adult reparative and fetal regenerative cells and supports the concept of using ESC-derived tenocytes as a cellular therapy. Comparing two- and three-dimensional culture also indicates three-dimensional culture as being a more physiologically relevant culture system for determining transcriptomic difference between the same cell types from different developmental stages.


Assuntos
Células-Tronco Embrionárias , Tenócitos , Animais , Diferenciação Celular , Células Cultivadas , Perfilação da Expressão Gênica , Cavalos , Humanos , Tendões
10.
Equine Vet J ; 40(2): 178-81, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18267891

RESUMO

Autologous mesenchymal progenitor cells (MPCs) purified from bone marrow aspirates are being used in the treatment of superficial digital flexor tendon (SDFT) injuries in the horse with promising results. In this study the fate of autologous and allogeneic MPCs following injection into the SDFT was monitored by stable transfection of MPCs with green fluorescent protein (GFP). Small lesions were created manually in one forelimb SDFT of 2 horses and injected with autologous MPCs, allogeneic MPCs or bone marrow supernatant alone. Post mortem examinations performed after 10 or 34 days revealed GFP labelled cells located mainly within injected lesions, but with a small proportion integrated into the crimp pattern of adjacent healthy areas of tendon. Furthermore, there was no visible cell mediated immune response to allogeneic MPCs in either of the host horses.


Assuntos
Doenças dos Cavalos/terapia , Cavalos/lesões , Transplante de Células-Tronco Mesenquimais/veterinária , Células-Tronco Mesenquimais , Traumatismos dos Tendões/veterinária , Animais , Proteínas de Fluorescência Verde , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/patologia , Traumatismos dos Tendões/terapia , Tendões , Transplante Autólogo , Resultado do Tratamento
11.
Stem Cells Dev ; 16(5): 789-96, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17999600

RESUMO

Embryonic stem-like (ES-like) cells have now been derived from the inner cell mass (ICM) of horse embryos at the blastocyst stage. Because they have been shown to express cell-surface antigens found in both human and mouse ES cells, the present study investigated gene expression patterns in day-7 horse blastocysts from which the horse ES-like cells had been derived originally. The genes studied included Oct-4, stage-specific embryonic antigen-1 (SSEA-1), SSEA-3, SSEA-4, tumor rejection antigen-1-60 (TRA-1-60), TRA-1-81, and alkaline phosphatase activity, and whereas all three of the SSEA antigens were expressed in both the ICM and the trophoblast on day 7, Oct-4, TRA-1-60, TRA-1-81, and alkaline phosphatase activity were localized mostly in the ICM. Upon in vitro differentiation of the horse ES-like cells, their expression of the stem cell markers was abolished. Therefore, the species-specific expression pattern of stem cell markers in horse ES-like cells reflects gene expression in the blastocysts from which they are derived.


Assuntos
Antígenos de Superfície/genética , Blastocisto/metabolismo , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Equidae/genética , Regulação da Expressão Gênica , Células-Tronco Pluripotentes/metabolismo , Animais , Antígenos de Superfície/metabolismo , Biomarcadores/metabolismo , Blastocisto/citologia , Diferenciação Celular , Amarelo de Eosina-(YS) , Hematoxilina , Imuno-Histoquímica , Especificidade de Órgãos
12.
Environ Health Perspect ; 57: 177-83, 1984 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6499802

RESUMO

A comparison was made of the absorption and elimination rates of 2-propoxyethyl acetate (PEA) and 2-ethoxyethyl acetate (EEA) following inhalation, dermal application or IV administration. Male beagle dogs were exposed to 50 ppm PEA or EEA for 5 hr, and breath samples were collected during the exposure and a 3-hr recovery period. Both compounds were rapidly absorbed through the lungs. After 10 min of exposure, the concentrations of the parent compounds in the expired breath were 5 to 10 ppm (80-90% absorption) and reached plateau values at about 3 hr of 13 ppm for PEA (74% absorption) and 16 ppm for EEA (68% absorption). Post-exposure breath samples declined exponentially to 0.5 ppm and 2 ppm after 3 hr for PEA and EEA, respectively. Expired concentrations of PEA were slightly, but significantly (p less than 0.025), lower than those of EEA at corresponding times during the exposure. After IV dosing with 1 mg/kg [ethyl-1,2-14C]PEA, the urine contained 61% and 88% of the dose in 4 and 24 hr, respectively. [14C]EEA was eliminated more slowly, with 20% and 61% of the dose appearing in the urine in 4 and 24 hr, respectively. Blood elimination half-lives were 1.6 hr for [14C]PEA and 7.9 hr for [14C]EEA. Only trace amounts of 14CO2 (less than 1%) or volatile materials (less than 0.1%) were detected in the expired air with either compound. For studies of percutaneous absorption, [14C]PEA or [14C]EEA was added to undiluted compound and applied in a glass cell to a shaved area on a dog's thorax for 30 or 60 min.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Etilenoglicóis/metabolismo , Pulmão/metabolismo , Absorção Cutânea , Administração Tópica , Animais , Cães , Injeções Intravenosas , Cinética , Masculino , Fatores de Tempo
13.
Infect Control Hosp Epidemiol ; 24(7): 472-6, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12887233

RESUMO

BACKGROUND AND OBJECTIVE: Aspergillus fumigatus is a major pathogen causing nosocomial infections. Hospital outbreaks of invasive aspergillosis have been associated with the renovation and construction of buildings. Building construction work for fire safety upgrading was undertaken during a 16-week period in 2001 at Box Hill Hospital. This study was designed to examine the effect of construction on invasive aspergillosis when using standard and additional protective measures. METHODS: Baseline air sampling was conducted in 18 areas. The validity of the air sampling was assessed by comparing the ability of two air samplers to detect Aspergillus conidia. Surveillance of nosocomial Aspergillus infection was conducted by reviewing the records of patients with a sputum culture positive for Aspergillus and those prescribed amphotericin or itraconazole for the period of construction activity and the same period the previous year. RESULTS: Aspergillus was isolated infrequently and there was no statistically significant difference in the levels of viable pathogenic fungi between areas w here construction work was undertaken and areas where it wasnot undertaken. A moderate agreement was observed between the two air samplers (kappa = 0.4; P < .05). There was no difference in the incidence of invasive aspergillosis between 2000 and 2001 (incidence density ratio, 1.2; 95% confidence interval, 0.3 to 4.1). CONCLUSION: The influence of construction work performed with protective measures needs to be examined in an environment with higher levels of airborne fungi to confirm the findings of this study.


Assuntos
Microbiologia do Ar , Aspergilose/transmissão , Aspergillus fumigatus/isolamento & purificação , Infecção Hospitalar/transmissão , Arquitetura Hospitalar , Austrália , Infecção Hospitalar/microbiologia , Humanos , Exposição Ocupacional
14.
Toxicol Sci ; 58(2): 377-85, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11099649

RESUMO

B6C3F1 mice were treated with 0, 100, 500, 1500, or 6000 ppm di(2-ethylhexyl)phthalate (DEHP) in the diet for up to 104 weeks. Blood and urine were analyzed at Weeks 26, 52, 78, and 104 from 10 animals per sex per group. Body weights and food consumption were measured weekly for the first 16 weeks, then monthly thereafter. Survival was reduced for mice receiving 6000 ppm DEHP. Overall weight gains were significantly lower for the 6000-ppm male group, but there was no difference among female groups. Food consumption was not affected by exposure. No biologically significant changes in clinical chemistry, hematology, or urinalysis were observed. After 104 weeks of exposure, kidney weights for the 500- and 1500-ppm male, and 6000-ppm male/female groups were significantly lower than for the controls. Significantly higher liver weight was seen for the 500-, 1500-, and 6000-ppm male groups and the 6000-ppm female group of mice. Testis weights for the 500-, 1500-, and 6000-ppm males were significantly lower than for the controls. Uterine weights for the 6000-ppm group were significantly lower than for the controls. All organs were examined for histopathology. The incidence of hepatocellular lesions has been reported separately (R. M. David et al., 1999. Toxicol. Sci. 50, 195-205). Tumors were observed at > or = 500-ppm dosages, where peroxisome proliferation was significantly increased. A NOEL for both tumors and peroxisome proliferation was 100 ppm. In the study presented here, bilateral hypospermia in the testes of male mice, hepatocyte pigmentation and cytoplasmic eosinophilia in the liver, and chronic progressive nephropathy of male and female mice were observed at 6000 ppm. Hypospermia and chronic progressive nephropathy were also observed at 1500 ppm, where peroxisome proliferation was 2.7-6.8-fold higher than controls. Many lesions observed in rats were not seen in mice. A dose level of 500 ppm (98.5-116.8 mg/kg/day) was identified as a no-observed-adverse-effect level (NOAEL) for noncarcinogenic effects.


Assuntos
Dietilexilftalato/toxicidade , Animais , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos , Tamanho do Órgão/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testículo/patologia
15.
Toxicol Sci ; 55(2): 433-43, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10828276

RESUMO

Fischer 344 rats were treated with 0, 100, 500, 2500, or 12,500 ppm di(2-ethylhexyl)phthalate (DEHP) in the diet for up to 104 weeks. Blood and urine were analyzed at weeks 26, 52, 78, and 104 from 10 animals per sex per group. Survival was slightly but not statistically reduced for rats receiving 12,500 ppm DEHP. Body weights and food consumption were significantly reduced for rats receiving the highest dose level of DEHP and occasionally for the male 2500-ppm group. BUN and albumin were significantly higher and globulin lower at nearly every sampling interval for the 12,500-ppm group compared with the controls. There was an increase in the mean activities of AST and ALT at 104 weeks, but no statistically significant differences were seen. Erythrocyte count, hemoglobin, and hematocrit values for the 12,500-ppm group were significantly lower than controls at nearly every sampling interval. No other differences in hematology were seen. No toxicologically significant changes were observed in urinalysis. At termination, relative lung weights for the 2500- and 12,500-ppm male groups of rats were significantly higher than for the controls. Absolute and relative liver and kidney weights for the 2500- and 12,500-ppm male rats, and liver weights for 12,500-ppm female rats were higher compared with the controls. Absolute and relative testes weights for the 12, 500-ppm male rats were lower compared with the controls. All organs were examined for histopathology. The incidence of hepatocellular lesions has been reported separately and correlated with the induction of peroxisomal enzyme activity (David et al., 1999). A dose level of 500 ppm was the NOEL for peroxisome proliferation. Bilateral aspermatogenesis in the testes, castration cells in the pituitary gland, spongiosis hepatis, and pancreatic acinar cell adenoma were observed for 12,500-ppm male rats. Aspermatogenesis and spongiosis hepatis were observed for 2500-ppm male rats, and aspermatogenesis was seen at 500 ppm. DEHP exposure exacerbated age-, species- or strain-related lesions such as mineralization of the renal papilla and chronic progressive nephropathy in male rats. Kupffer cell pigmentation and renal tubule pigmentation were seen in male and female 12,500-ppm rats. The increased incidence of spongiosis hepatis correlated with increased palmitoyl CoA oxidase activity, but the incidence of pancreatic acinar cell adenoma was increased only at the highest dose level of 12,500 ppm. These lesions, although typical of those seen with other peroxisome proliferators, may respond differently depending on the potency of the peroxisome proliferator. A dose level of 500 ppm (28.9-36.1 mg/kg/day) was considered to be the NOAEL.


Assuntos
Dietilexilftalato/toxicidade , Adenoma/induzido quimicamente , Adenoma/patologia , Animais , Nitrogênio da Ureia Sanguínea , Peso Corporal/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Contagem de Eritrócitos/efeitos dos fármacos , Feminino , Hematócrito , Hemoglobinas/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Neoplasias Pancreáticas/induzido quimicamente , Neoplasias Pancreáticas/patologia , Proliferadores de Peroxissomos/toxicidade , Ratos , Ratos Endogâmicos F344 , Albumina Sérica/efeitos dos fármacos , Soroglobulinas/efeitos dos fármacos , Testes de Toxicidade
16.
Toxicol Sci ; 50(2): 195-205, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10478855

RESUMO

This study compared the levels of cell proliferation and peroxisome proliferation in rodent liver with tumor incidence, to provide more information on the relationship between these events following chronic exposure. Fischer 344 rats were treated with 0, 100, 500, 2500, or 12,500 ppm DEHP, and B6C3F1 mice were treated with 0, 100, 500, 1500, or 6000 ppm DEHP in the diet for up to 104 weeks. Additional groups of rats and mice received the highest concentration for 78 weeks and then the control diet for an additional 26 weeks (recovery groups). Animals were terminated at weeks 79 and 105 for histopathologic examination. Elevated palmitoyl CoA oxidation activity and higher liver-to-body weight ratios were observed for the 2500- and 12,500-ppm groups of rats, and for the 500-, 1500-, and 6000-ppm groups of mice at Week 105. No increase in palmitoyl CoA oxidation activity was evident in the recovery group, and relative liver weights were near control levels following recovery. No hepatic cell proliferation was detected at Weeks 79 or 105 in either species although preliminary data indicated that cell proliferation did occur within the first 13 weeks of exposure. A significantly higher incidence of hepatocellular tumors was only observed for the 2500- and 12,500-ppm group and its recovery group of rats, and for the 500-, 1500-, and 6000-ppm groups and the recovery group of mice. The tumor incidences were reduced for the recovery groups compared with the groups fed DEHP continuously for 104 weeks. The data indicate that high levels of peroxisome proliferation and hepatomegaly are associated with DEHP hepatocarcinogenesis in rodent liver, and that the tumorigenic process may be arrested by cessation of DEHP treatment, suggesting that extended treatment with DEHP acts to promote tumor growth.


Assuntos
Carcinógenos/toxicidade , Dietilexilftalato/toxicidade , Hepatomegalia/induzido quimicamente , Neoplasias Hepáticas/induzido quimicamente , Transtornos Peroxissômicos/induzido quimicamente , Animais , Testes de Carcinogenicidade , Divisão Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Masculino , Camundongos , Tamanho do Órgão/efeitos dos fármacos , Oxirredução , Palmitoil Coenzima A/efeitos dos fármacos , Palmitoil Coenzima A/metabolismo , Proliferadores de Peroxissomos/toxicidade , Peroxissomos/enzimologia , Ratos , Ratos Endogâmicos F344 , Fatores Sexuais , Taxa de Sobrevida , Fatores de Tempo
17.
Phytopathology ; 90(7): 775-82, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18944498

RESUMO

ABSTRACT We examined the effects of fresh and composted animal manures on the development of root rot, dieback, and plant death caused by Phytophthora cinnamomi. Fresh chicken manure, or chicken manure composted for 5 weeks before incorporation into the potting mix (25%, vol/vol), significantly reduced pathogen survival and the development of symptoms on Lupinus albus seedlings. Chicken manure composted for 2 weeks was less suppressive. Cow, sheep, and horse manure, whether fresh or composted, did not consistently suppress populations of P. cinnamomi or disease symptoms at the rates used (25%, vol/vol). All composts increased organic matter content, total biological activity, and populations of actinomycetes, fluorescent pseudomonads, and fungi. Only chicken manure stimulated endospore-forming bacteria, a factor that was strongly associated with seedling survival. Fallowing the potting mix for an additional 8 weeks after the first harvest increased the survival of lupin seedlings in a second bioassay, with survival rates in chicken manure compost-amended potting mix exceeding 90%. These data suggest that the ability of composted manure to stimulate sustained biological activity, in particular the activity of endospore-forming bacteria, is the key factor in reducing disease symptoms caused by P. cinnamomi. Supporting these results, the survival of rooted cuttings of Thryptomene calycina was significantly higher in sand-peat potting mix following amendment with commercially available chicken manure (15% vol/vol). However, this protection was reduced if the potting mix was steam pasteurized before amendment, indicating that suppression was due to endogenous as well as introduced microbes. Chicken manure compost incorporated at 5% (vol/vol) or more was strongly phytotoxic to young Banksia spinulosa plants and is not suitable as an amendment for phosphorus-sensitive plants.

18.
Food Chem Toxicol ; 36(6): 521-7, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9674960

RESUMO

These studies investigated the migration of di(2-ethylhexyl) phthalate (DEHP) contained as a plasticizer in polyvinyl chloride (PVC) from plastic film and its absorption through rat skin in iivo. Sheets of PVC film (15 cm2) plasticized with [14C]DEHP were applied to the shaved backs of eight male rats in two separate experiments. For Study I, the PVC film was removed after 24 hr, the animals were rewrapped to prevent them from ingesting any residual DEHP at the exposure site, and urine and faeces were collected at regular intervals for 7 days. For Study II, the PVC film was removed after 24 hr, and the animals were immediately killed by CO2 inhalation. Urine and faeces were collected at 24 hr, and the exposure site was washed and rinsed to remove residual [14C]DEHP. In both studies, the amounts of radioactivity transferred from the film were extremely small, amounting to 0.0643% (Study I) and 0.126% (Study II) of that applied. The transferred radioactivity was found to be in three separate fractions. Radioactivity readily removed from the skin (mean 75% of the transferred radioactivity), radioactivity remaining at the application site at sacrifice. and absorbed radioactivity, that is, that distributed systemically or eliminated. The mean absorption rates for DEHP, calculated from the sum of the quantities absorbed plus that present in the exposure site, were: Study I, 0.239, and Study II, 0.242 microg/cm2/hr.


Assuntos
Dietilexilftalato/metabolismo , Plastificantes/metabolismo , Cloreto de Polivinila/química , Pele/metabolismo , Animais , Radioisótopos de Carbono , Dietilexilftalato/análise , Fezes/química , Masculino , Plastificantes/análise , Ratos , Ratos Endogâmicos F344 , Absorção Cutânea
19.
Plast Reconstr Surg ; 103(6): 1667-73, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10323700

RESUMO

Sternal dehiscence may be defined as separation of the bony sternum and manubrium following median sternotomy. It may occur at any time postoperatively and has various etiologies. Restoration of sternal integrity in sternal dehiscence is a challenging problem, particularly when associated with deep-seated infection. This report reviews a single-stage technique that virtually eliminates the infected sternotomy wound and provides anatomic reduction and stabilization of the sternum. Complete debridement of infected and/or nonviable soft tissue, bone, and cartilage is followed by pulse irrigation. Parallel stainless steel mandibular reconstruction plates are then placed on each side of the remaining sternum and wired together. One or more transmanubrial compression plates may be added. Bilateral pectoralis major musculocutaneous flap advancement and primary skin closure is performed over two to three closed suction drains. From January of 1994 to July of 1996, this technique was used by the same surgeon in 26 male and 4 female patients aged 43 to 78 years (mean = 61). Indications for the operation were sternal dehiscence with infection (osteomyelitis and/or mediastinitis) in 14 patients and sternal dehiscence without infection in 16 patients. All patients survived to discharge with mean time on the ventilator, intensive care unit length of stay, and postoperative length of stay of 0.7, 2, and 8 days, respectively. Choice and duration of antibiotics were based on culture results and operative findings. Subsequent hardware removal was necessary in one patient for hardware loosening and three patients for late periplate infection. A closed wound was eventually achieved in all 30 patients, and sternal stability was restored in 29 patients. In the management of sternal dehiscence, the described technique of internal fixation can provide anatomic sternal reduction and stabilization, elimination of infection, and wound closure in a single-stage operation. Successful outcomes were achieved despite the presence of severe infection.


Assuntos
Fixadores Internos , Esterno/cirurgia , Deiscência da Ferida Operatória/cirurgia , Infecção da Ferida Cirúrgica/cirurgia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Operatórios/métodos
20.
Persoonia ; 28: 138-82, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23105159

RESUMO

Novel species of microfungi described in the present study include the following from Australia: Phytophthora amnicola from still water, Gnomoniopsis smithogilvyi from Castanea sp., Pseudoplagiostoma corymbiae from Corymbia sp., Diaporthe eucalyptorum from Eucalyptus sp., Sporisorium andrewmitchellii from Enneapogon aff. lindleyanus, Myrmecridium banksiae from Banksia, and Pilidiella wangiensis from Eucalyptus sp. Several species are also described from South Africa, namely: Gondwanamyces wingfieldii from Protea caffra, Montagnula aloes from Aloe sp., Diaporthe canthii from Canthium inerne, Phyllosticta ericarum from Erica gracilis, Coleophoma proteae from Protea caffra, Toxicocladosporium strelitziae from Strelitzia reginae, and Devriesia agapanthi from Agapanthus africanus. Other species include Phytophthora asparagi from Asparagus officinalis (USA), and Diaporthe passiflorae from Passiflora edulis (South America). Furthermore, novel genera of coelomycetes include Chrysocrypta corymbiae from Corymbia sp. (Australia), Trinosporium guianense, isolated as a contaminant (French Guiana), and Xenosonderhenia syzygii, from Syzygium cordatum (South Africa). Pseudopenidiella piceae from Picea abies (Czech Republic), and Phaeocercospora colophospermi from Colophospermum mopane (South Africa) represent novel genera of hyphomycetes. Morphological and culture characteristics along with ITS DNA barcodes are provided for all taxa.

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