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1.
Phys Chem Chem Phys ; 20(8): 5530-5544, 2018 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-29168510

RESUMO

We present first results on a newly built broadband emission spectrometer for the laboratory making use of a double sideband (DSB) heterodyne receiver. The new spectrometer is perfectly suited for high-resolution emission spectroscopy of molecules of astrophysical importance. The current SIS receiver operates at RF frequencies between 270 and 390 GHz, coincident with Band 7 of the ALMA telescope. The instantaneous bandwidth is 5 GHz (DSB). In this work the full spectrometer and its components are described. Its performance, in particular its sensitivity, stability, reproducibility and systematic errors, is characterized in detail. For this purpose very broad band emission spectra of methyl cyanide have been recorded and compared to theoretical spectra. Isotopic variants are found in natural abundance and features attributed to vibrationally excited species are all recorded in the same spectrum. The performance of the new spectrometer is compared extensively to that of a traditional FM-absorption spectrometer and to recent versions of chirped-pulse spectrometers operated in the mm-wave regime. Further applications and future advancements of the current instrument are discussed.

2.
Vet Pathol ; 52(6): 1254-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25637084

RESUMO

Although Chlamydia causes disease of the urethra and prostate of male koalas, its impact on the testis and epididymis has not been examined. This study describes chronic-active and granulomatous orchitis and epididymitis with interstitial fibrosis associated with infection by Chlamydia pecorum in 2 of 18 adult male koalas being euthanized at a koala hospital, 8 of which also had chlamydial prostatitis. By immunohistochemistry and transmission electron microscopy, chlamydial inclusions were demonstrated within Sertoli cells directly associated with mild inflammation surrounding intact seminiferous and epididymal tubules, marked pyogranulomatous inflammation around disrupted tubules, replacement of tubules by interstitial fibrosis, and aspermia. The presence of C. pecorum but not Chlamydia pneumoniae was detected by quantitative polymerase chain reaction of formalin-fixed tissues of the left and right testes and right epididymis in 1 animal. This is the first report of orchitis and epididymitis in a koala infected with C. pecorum.


Assuntos
Infecções por Chlamydia/veterinária , Chlamydia/isolamento & purificação , Epididimite/veterinária , Orquite/veterinária , Phascolarctidae/microbiologia , Animais , Chlamydia/genética , Infecções por Chlamydia/microbiologia , Infecções por Chlamydia/patologia , Epididimite/microbiologia , Epididimite/patologia , Fibrose/microbiologia , Fibrose/patologia , Fibrose/veterinária , Corpos de Inclusão/microbiologia , Corpos de Inclusão/patologia , Masculino , Orquite/microbiologia , Orquite/patologia , Testículo/patologia
3.
Heredity (Edinb) ; 113(4): 287-96, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24690756

RESUMO

Major histocompatibility complex class II (MHCII) genes code for proteins that bind and present antigenic peptides and trigger the adaptive immune response. We present a broad geographical study of MHCII DA ß1 (DAB) and DB ß1 (DBB) variants of the koala (Phascolarctos cinereus; n=191) from 12 populations across eastern Australia, with a total of 13 DAB and 7 DBB variants found. We identified greater MHCII variation and, possibly, additional gene copies in koala populations in the north (Queensland and New South Wales) relative to the south (Victoria), confirmed by STRUCTURE analyses and genetic differentiation using analysis of molecular variance. The higher MHCII diversity in the north relative to south could potentially be attributed to (i) significant founder effect in Victorian populations linked to historical translocation of bottlenecked koala populations and (ii) increased pathogen-driven balancing selection and/or local genetic drift in the north. Low MHCII genetic diversity in koalas from the south could reduce their potential response to disease, although the three DAB variants found in the south had substantial sequence divergence between variants. This study assessing MHCII diversity in the koala with historical translocations in some populations contributes to understanding the effects of population translocations on functional genetic diversity.


Assuntos
Genes MHC da Classe II , Variação Genética , Antígenos HLA-D/genética , Phascolarctidae/genética , Sequência de Aminoácidos , Animais , Austrália , Feminino , Deriva Genética , Genética Populacional , Antígenos HLA-D/química , Masculino , Dados de Sequência Molecular , Phascolarctidae/classificação , Filogenia , Alinhamento de Sequência
4.
Eur J Clin Microbiol Infect Dis ; 33(8): 1425-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24627239

RESUMO

Clostridium difficile infection (CDI) is one of the most frequent causes of healthcare-associated infections, and its rates are also increasing in the community. The management of CDI has become a major challenge, given growing rates of recurrences and failures with standard antibiotic therapy. Mounting evidence suggests that fecal microbiota transplantation (FMT) may be effective; however, as there is a paucity of data with regard to repeat FMT for primary non-response to this treatment, this study examined the outcome of multiple FMTs for recurrent CDI. Case records were reviewed for 94 patients who underwent FMT via retention enema for recurrent or refractory CDI during the period 2008-2012. Demographic information, treatment data, and clinical resolution rates were examined for single FMT and cumulative resolution was assessed for multiple FMTs in the context of ongoing symptoms. The cumulative clinical resolution following four or more FMTs was 86%. When antibiotic therapy was used between FMTs, the clinical resolution rate increased to 92%. There were no reported adverse events and no patients who were cured with FMT had further episodes of CDI at 6-24 months follow-up. Multiple FMTs administered through enemas is an effective, safe, and simple therapy for the management of recurrent or refractory CDI.


Assuntos
Clostridioides difficile/efeitos dos fármacos , Infecções por Clostridium/terapia , Infecção Hospitalar/terapia , Microbiota , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções por Clostridium/microbiologia , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana , Enema , Fezes/microbiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
5.
J Vet Pharmacol Ther ; 36(5): 486-93, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23406022

RESUMO

The pharmacokinetic profile of meloxicam in clinically healthy koalas (n = 15) was investigated. Single doses of meloxicam were administered intravenously (i.v.) (0.4 mg/kg; n = 5), subcutaneously (s.c.) (0.2 mg/kg; n = 1) or orally (0.2 mg/kg; n = 3), and multiple doses were administered to two groups of koalas via the oral or s.c. routes (n = 3 for both routes) with a loading dose of 0.2 mg/kg for day 1 followed by 0.1 mg/kg s.i.d for a further 3 days. Plasma meloxicam concentrations were quantified by high-performance liquid chromatography. Following i.v. administration, meloxicam exhibited a rapid clearance (CL) of 0.44 ± 0.20 (SD) L/h/kg, a volume of distribution at terminal phase (Vz ) of 0.72 ± 0.22 L/kg and a volume of distribution at steady state (Vss ) of 0.22 ± 0.12 L/kg. Median plasma terminal half-life (t(1/2)) was 1.19 h (range 0.71-1.62 h). Following oral administration either from single or repeated doses, only maximum peak plasma concentration (C(max) 0.013 ± 0.001 and 0.014 ± 0.001 µg/mL, respectively) was measurable [limit of quantitation (LOQ) >0.01 µg/mL] between 4-8 h. Oral bioavailability was negligible in koalas. Plasma protein binding of meloxicam was ~98%. Three meloxicam metabolites were detected in plasma with one identified as the 5-hydroxy methyl derivative. This study demonstrated that koalas exhibited rapid CL and extremely poor oral bioavailability compared with other eutherian species. Accordingly, the currently recommended dose regimen of meloxicam for this species appears inadequate.


Assuntos
Anti-Inflamatórios não Esteroides/farmacocinética , Phascolarctidae/metabolismo , Tiazinas/farmacocinética , Tiazóis/farmacocinética , Administração Oral , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/sangue , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida de Alta Pressão/veterinária , Cromatografia de Fase Reversa/métodos , Cromatografia de Fase Reversa/veterinária , Feminino , Injeções Intravenosas/veterinária , Injeções Subcutâneas/veterinária , Masculino , Meloxicam , Phascolarctidae/sangue , Tiazinas/administração & dosagem , Tiazinas/sangue , Tiazóis/administração & dosagem , Tiazóis/sangue
6.
J Vet Pharmacol Ther ; 36(5): 478-85, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23157306

RESUMO

Clinically normal koalas (n = 19) received a single dose of intravenous (i.v.) chloramphenicol sodium succinate (SS) (25 mg/kg; n = 6), subcutaneous (s.c.) chloramphenicol SS (60 mg/kg; n = 7) or s.c. chloramphenicol base (60 mg/kg; n = 6). Serial plasma samples were collected over 24-48 h, and chloramphenicol concentrations were determined using a validated high-performance liquid chromatography assay. The median (range) apparent clearance (CL/F) and elimination half-life (t(1/2)) of chloramphenicol after i.v. chloramphenicol SS administration were 0.52 (0.35-0.99) L/h/kg and 1.13 (0.76-1.40) h, respectively. Although the area under the concentration-time curve was comparable for the two s.c. formulations, the absorption rate-limited disposition of chloramphenicol base resulted in a lower median C(max) (2.52; range 0.75-6.80 µg/mL) and longer median tmax (8.00; range 4.00-12.00 h) than chloramphenicol SS (C(max) 20.37, range 13.88-25.15 µg/mL; t(max) 1.25, range 1.00-2.00 h). When these results were compared with susceptibility data for human Chlamydia isolates, the expected efficacy of the current chloramphenicol dosing regimen used in koalas to treat chlamydiosis remains uncertain and at odds with clinical observations.


Assuntos
Antibacterianos/farmacocinética , Cloranfenicol/análogos & derivados , Cloranfenicol/farmacocinética , Phascolarctidae/metabolismo , Animais , Antibacterianos/administração & dosagem , Cloranfenicol/administração & dosagem , Cloranfenicol/sangue , Cromatografia Líquida de Alta Pressão , Feminino , Injeções Intravenosas/veterinária , Injeções Subcutâneas/veterinária , Masculino , Phascolarctidae/sangue
7.
J Vet Pharmacol Ther ; 35(2): 147-54, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21569052

RESUMO

Nine mature koalas with chlamydiosis, typically keratoconjunctivitis and/or urogenital tract infection, were treated with daily subcutaneous injections of chloramphenicol at 60 mg/kg for 45 days (five koalas), or for a shorter duration (four koalas). All koalas were initially positive for Chlamydia pecorum as determined by real-time polymerase chain reaction (qPCR). Plasma chloramphenicol concentrations were determined at t = 0, 1, 2, 4, 8, and 24 h after the day 1 injection (nine koalas) and after the day 15 injection (seven koalas). Chloramphenicol reached a median (and range) maximum plasma concentration of 3.03 (1.32-5.03 µg/mL) at 4 (1-8 h) after the day 1 injection and 4.82 (1.97-27.55 µg/mL) at 1 (1-2 h) after day 15. The median (and range) of AUC(0-24) on day 1 and day 15 were 48.14 (22.37-81.14 µg·h/mL) and 50.83 (28.43-123.99 µg·h/mL), respectively. The area under the moment curve (AUMC)(0-24) median (and range) for day 1 and day 15 were 530.03 (233.05-798.97 h) and 458.15 (291.72-1093.58 h), respectively. Swabs were positive for chlamydial DNA pretreatment, and all koalas except one, produced swabs negative for chlamydial DNA during treatment and which remained so, for 2-63 days after treatment, however whether chloramphenicol treatment prevented long-term recrudescence of infection was not established. At this dose and dosing frequency, chloramphenicol appeared to control mild chlamydial infection and prevent shedding, but severe urogenital disease did not appear to respond to chloramphenicol at this dosage regime. For koalas affected by severe chlamydiosis, antibiotics alone are not sufficient to effect a cure, possibly because of structural or metabolic changes associated with chronic disease and inflammation.


Assuntos
Antibacterianos/farmacocinética , Antibacterianos/uso terapêutico , Infecções por Chlamydia/veterinária , Cloranfenicol/farmacocinética , Cloranfenicol/uso terapêutico , Phascolarctidae/sangue , Animais , Animais Selvagens , Área Sob a Curva , Infecções por Chlamydia/tratamento farmacológico , Feminino , Masculino
8.
Chemosphere ; 299: 134418, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35351478

RESUMO

The contamination of microplastics in aquatic environment is regarded as a serious threat to ecosystem especially to aquatic environment. Microplastic pollution associated problems including their bioaccumulation and ecological risks have become a major concern of the public and scientific community. The removal of microplastics from their discharge points is an effective way to mitigate the adverse effects of microplastic pollution, hence has been the central of the research in this realm. Presently, most of the commonly used water or wastewater treatment technologies are capable of removing microplastic to certain extent, although they are not intentionally installed for this reason. Nevertheless, recognizing the adverse effects posed by microplastic pollution, more efforts are still desired to enhance the current microplastic removal technologies. With their structural multifunctionalities and flexibility, nanomaterials have been increasingly used for water and wastewater treatment to improve the treatment efficiency. Particularly, the unique features of nanomaterials have been harnessed in synthesizing high performance adsorbent and photocatalyst for microplastic removal from aqueous environment. This review looks into the potentials of nanomaterials in offering constructive solutions to resolve the bottlenecks and enhance the efficiencies of the existing materials used for microplastic removal. The current efforts and research direction of which studies can dedicate to improve microplastic removal from water environment with the augmentation of nanomaterial-enabled strategies are discussed. The progresses made to date have witnessed the benefits of harnessing the structural and dimensional advantages of nanomaterials to enhance the efficiency of existing microplastic treatment processes to achieve a more sustainable microplastic cleanup.


Assuntos
Nanoestruturas , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental , Microplásticos , Plásticos , Água , Poluentes Químicos da Água/análise
9.
Int J Clin Pract ; 65(7): 784-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21564449

RESUMO

BACKGROUND: The lipoglycopeptide antibiotic, telavancin, may interfere with some laboratory coagulation tests including prothrombin time (PT) and activated partial thromboplastin time (aPTT). OBJECTIVE: To evaluate the effects of telavancin on PT and aPTT assays in common use. METHODS: Pooled normal human plasma was spiked with telavancin 10, 20, 100 or 200 µg/ml (equivalent to trough, 2 × trough, peak and 2 × peak clinical plasma concentrations, respectively) or diluent control (0.9% sodium chloride). Samples were analysed using 16 PT reagents and seven aPTT reagents. RESULTS: Telavancin 200 µg/ml (corresponding to 2 × peak clinical plasma concentration), produced significant PT prolongation (> 9% difference vs. diluent control) with all the 16 PT reagents (range 12% to > 600%). At lower telavancin concentrations, PT prolongation was dose-dependent and varied among reagents, but appeared greatest with preparations containing recombinant tissue factor. With telavancin 10 µg/ml (equivalent to trough), PT prolongation was 10% with HemosIL(®) PT-Fibrinogen Recombinant, while ranging from 5% to -1% with all other reagents. Significant (> 34% difference vs. baseline) and dose-dependent aPTT prolongation was observed with all the seven reagents in samples spiked with telavancin 100 or 200 µg/ml (range 65-142% at 200 µg/ml). aPTT reagents containing a silica activator appeared to be more sensitive to telavancin interference. Telavancin 10 µg/ml was not associated with increased aPTT with any of the reagents tested. CONCLUSIONS: Telavancin has the potential to prolong both PT and aPTT in vitro. It is recommended that samples for PT or aPTT be obtained just prior to a telavancin dose (trough).


Assuntos
Aminoglicosídeos , Antibacterianos , Coagulação Sanguínea/efeitos dos fármacos , Aminoglicosídeos/farmacologia , Antibacterianos/farmacologia , Contraindicações , Humanos , Lipoglicopeptídeos , Tempo de Tromboplastina Parcial/normas , Tempo de Protrombina/normas , Valores de Referência
10.
Toxicon ; 200: 38-47, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34237340

RESUMO

Induction of CD8+ T cell responses against tumor cells and intracellular pathogens is an important goal of modern vaccinology. One approach of translational interest is the use of liposomes encapsulating pore-forming proteins (PFPs), such as Listeriolysin O (LLO), which has shown efficacy at priming strong and sustained CD8+ T cell responses. Recently, we have demonstrated that Sticholysin II (StII), a PFP from the sea anemone Stichodactyla helianthus, co-encapsulated into liposomes with ovalbumin (OVA) was able to stimulate, antigen presenting cells, antigen-specific CD8+ T cells and anti-tumor activity in mice. In the present study, we aimed to compare StII and LLO in terms of their abilities to stimulate dendritic cells and to induce major histocompatibility complex (MHC) class I restricted T cell responses against OVA. Interestingly, StII exhibited similar abilities to LLO in vitro of inducing dendritic cells maturation, as measured by increased expression of CD40, CD80, CD86 and MHC-class II molecules, and of stimulating OVA cross-presentation to a CD8+ T cell line. Remarkably, using an ex vivo Enzyme-Linked ImmunoSpot Assay (ELISPOT) to monitor gamma interferon (INF-γ) producing effector memory CD8+ T cells, liposomal formulations containing either StII or LLO induced comparable frequencies of OVA-specific INF-γ producing CD8+ T cells in mice that were sustained in time. However, StII-containing liposomes stimulated antigen-specific memory CD8+ T cells with a higher potential to secrete IFN-γ than liposomes encapsulating LLO. This StII immunostimulatory property further supports its use for the rational design of T cell vaccines against cancers and intracellular pathogens. In summary, this study indicates that StII has immunostimulatory properties similar to LLO, despite being evolutionarily distant PFPs.


Assuntos
Linfócitos T CD8-Positivos , Linfócitos T Citotóxicos , Animais , Toxinas Bacterianas , Venenos de Cnidários , Células Dendríticas , Proteínas de Choque Térmico , Proteínas Hemolisinas , Camundongos , Camundongos Endogâmicos C57BL , Ovalbumina
11.
J Exp Med ; 139(2): 414-26, 1974 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-4359400

RESUMO

The M variant of encephalomyocarditis virus produces a diabetes mellitus-like disease in DBA/2 mice but not in animals of the C3H strain. Fewer than one-third of infected F(1) (DBA/2 x C3H) progeny exhibit the disease, whereas the prevalence in backcrosses (F(1) x DBA/2, F(1) x C3H) is comparable to the parental inbred strain. Thus, the mode of inheritance of the diabetic predisposition appears to be polygenic. DBA/2 animals develop striking inflammatory and necrotizing lesions of the islets of Langerhans; in contrast, alterations of the insular tissue in the C3H mice are minimal. Although metabolic abnormalities appear to be consequent to lesions of beta cells, the factors influencing the severity of these insular changes are incompletely understood.


Assuntos
Diabetes Mellitus/genética , Modelos Animais de Doenças , Vírus da Encefalomiocardite/crescimento & desenvolvimento , Camundongos Endogâmicos C3H , Camundongos Endogâmicos DBA , Animais , Anticorpos Antivirais/análise , Glicemia , Peso Corporal , Encéfalo/microbiologia , Cruzamentos Genéticos , Diabetes Mellitus/sangue , Diabetes Mellitus/etiologia , Diabetes Mellitus/imunologia , Diabetes Mellitus/urina , Vírus da Encefalomiocardite/imunologia , Feminino , Teste de Tolerância a Glucose , Glicosúria , Coração/microbiologia , Masculino , Camundongos , Pâncreas/microbiologia
12.
J Vet Pharmacol Ther ; 33(6): 595-604, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21062313

RESUMO

Koalas (n = 43) were treated daily for up to 8 weeks with enrofloxacin: 10 mg/kg subcutaneously (s.c.), 5 mg/kg s.c., or 20 mg/kg per os (p.o.); or marbofloxacin: 1.0-3.3 mg/kg p.o., 10 mg/kg p.o. or 5 mg/kg s.c. Serial plasma drug concentrations were determined on day 1 and again at approximately 2 weeks, by liquid chromatography. The median (range) plasma maximum concentrations (C(max) ) for enrofloxacin 5 mg/kg s.c. and 10 mg/kg s.c. were 0.83 (0.68-1.52) and 2.08 (1.34-2.96) µg/mL and the median (range) T(max) were 1.5 h (1-2) and 1 h (1-2) respectively. Plasma concentrations of orally dosed marbofloxacin were too low to be quantified. Oral administration of enrofloxacin suggested absorption rate limited disposition pharmacokinetics; the median (range) C(max) for enrofloxacin 20 mg/kg p.o. was 0.94 (0.76-1.0) µg/mL and the median (range) T(max) was 4 h (2-8). Oral absorption of both drugs was poor. Plasma protein binding for enrofloxacin was 55.4 ± 1.9% and marbofloxacin 49.5 ± 5.3%. Elevations in creatinine kinase activity were associated with drug injections. Enrofloxacin and marbofloxacin administered at these dosage and routes are unlikely to inhibit the growth of chlamydial pathogens in vivo.


Assuntos
Antibacterianos/farmacologia , Fluoroquinolonas/farmacologia , Fluoroquinolonas/farmacocinética , Phascolarctidae/metabolismo , Administração Oral , Animais , Antibacterianos/administração & dosagem , Enrofloxacina , Feminino , Fluoroquinolonas/administração & dosagem , Fluoroquinolonas/sangue , Injeções Subcutâneas/veterinária , Absorção Intestinal , Masculino , Phascolarctidae/sangue
13.
Child Abuse Negl ; 102: 104395, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32062425

RESUMO

BACKGROUND: Research on prevalence, risk factors, and prevention interventions for child sexual abuse has continued to focus on western and developed countries. Where country-level prevalence data or large-scale research exists, rates of child sexual abuse are consistently higher in developing and non-western countries than their western and developed counterparts. OBJECTIVE: We systematically reviewed research on the nature of child sexual abuse interventions in developing countries, the settings and populations included to identify types of child sexual abuse prevention initiatives being implemented in developing countries and their effectiveness. METHODS: Following PRISMA guidelines, we conducted a systematic search of six databases and identified eight studies to include in our analysis. RESULTS: Most empirically evaluated interventions in developing countries have focused on preschool and primary school-aged children. Most have focused on interventions delivered in educational settings, with a lack of focus on population-level interventions to prevent child sexual abuse. Researchers have used outcomes measuring knowledge or skills for young people in self-protection and help-seeking, not deployment of those skills, actual reduction in prevalence of CSA, or improvements in conditions of safety in organizational contexts. CONCLUSIONS: If the focus on school-based strategies to prevent child sexual abuse continues in developing countries, a significant gap in knowledge of the efficacy of population-level interventions outside of school contexts, and consistency across the application of interventions will remain. Evaluations are needed that address the efficacy of broader government-led or whole-of-community prevention interventions to reduce actual prevalence of child sexual abuse, or that can link increased knowledge and skill with reduced victimization.


Assuntos
Abuso Sexual na Infância/prevenção & controle , Países em Desenvolvimento/estatística & dados numéricos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino
14.
Br J Cancer ; 100(9): 1452-64, 2009 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-19401702

RESUMO

Tumour stroma gene expression in biopsy specimens may obscure the expression of tumour parenchyma, hampering the predictive power of microarrays. We aimed to assess the utility of fluorescence-activated cell sorting (FACS) for generating cell populations for gene expression analysis and to compare the gene expression of FACS-purified tumour parenchyma to that of whole tumour biopsies. Single cell suspensions were generated from colorectal tumour biopsies and tumour parenchyma was separated using FACS. Fluorescence-activated cell sorting allowed reliable estimation and purification of cell populations, generating parenchymal purity above 90%. RNA from FACS-purified and corresponding whole tumour biopsies was hybridised to Affymetrix oligonucleotide microarrays. Whole tumour and parenchymal samples demonstrated differential gene expression, with 289 genes significantly overexpressed in the whole tumour, many of which were consistent with stromal gene expression (e.g., COL6A3, COL1A2, POSTN, TIMP2). Genes characteristic of colorectal carcinoma were overexpressed in the FACS-purified cells (e.g., HOX2D and RHOB). We found FACS to be a robust method for generating samples for gene expression analysis, allowing simultaneous assessment of parenchymal and stromal compartments. Gross stromal contamination may affect the interpretation of cancer gene expression microarray experiments, with implications for hypotheses generation and the stability of expression signatures used for predicting clinical outcomes.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Células Estromais/patologia , Biópsia , Moléculas de Adesão Celular/genética , Separação Celular/métodos , Colágeno/genética , Colágeno Tipo I , Colágeno Tipo VI/genética , Citometria de Fluxo , Perfilação da Expressão Gênica/métodos , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , Inibidor Tecidual de Metaloproteinase-2/genética
15.
J Cell Biol ; 101(1): 217-26, 1985 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-4008529

RESUMO

Sympathetic neurons taken from rat superior cervical ganglia and grown in culture acquire cholinergic function under certain conditions. These cholinergic sympathetic neurons, however, retain a number of adrenergic properties, including the enzymes involved in the synthesis of norepinephrine (NE) and the storage of measurable amounts of NE. These neurons also retain a high affinity uptake system for NE; despite this, the majority of the synaptic vesicles remain clear even after incubation in catecholamines. The present study shows, however, that if these neurons are depolarized before incubation in catecholamine, the synaptic vesicles acquire dense cores indicative of amine storage. These manipulations are successful when cholinergic function is induced with either a medium that contains human placental serum and embryo extract or with heart-conditioned medium, and when the catecholamine is either NE or 5-hydroxydopamine. In some experiments, neurons are grown at low densities and shown to have cholinergic function by electrophysiological criteria. After incubation in NE, only 6% of the synaptic vesicles have dense cores. In contrast, similar neurons depolarized (80 mM K+) before incubation in catecholamine contain 82% dense-cored vesicles. These results are confirmed in network cultures where the percentage of dense-cored vesicles is increased 2.5 to 6.5 times by depolarizing the neurons before incubation with catecholamine. In both single neurons and in network cultures, the vesicle reloading is inhibited by reducing vesicle release during depolarization with an increased Mg++/Ca++ ratio or by blocking NE uptake either at the plasma membrane (desipramine) or at the vesicle membrane (reserpine). In addition, choline appears to play a competitive role because its presence during incubation in NE or after reloading results in decreased numbers of dense-cored vesicles. We conclude that the depolarization step preceding catecholamine incubation acts to empty the vesicles of acetylcholine, thus allowing them to reload with catecholamine. These data also suggest that the same vesicles may contain both neurotransmitters simultaneously.


Assuntos
Acetilcolina/metabolismo , Fibras Colinérgicas/metabolismo , Gânglios Simpáticos/metabolismo , Hidroxidopaminas/metabolismo , Norepinefrina/metabolismo , Vesículas Sinápticas/metabolismo , Animais , Fibras Colinérgicas/ultraestrutura , Meios de Cultura , Técnicas de Cultura , Potenciais da Membrana/efeitos dos fármacos , Potássio/farmacologia , Ratos , Vesículas Sinápticas/ultraestrutura
16.
J Cell Biol ; 113(2): 417-28, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2010469

RESUMO

We have examined the effects of collagen IV on the morphological development of embryonic rat sympathetic neurons in vitro. In short-term (less than or equal to 24 h) culture, collagen IV accelerated process outgrowth, causing increases in the number of neurites and total neuritic length. Analysis of proteolytic fragments of collagen IV indicated that the NC1 domain was nearly as active as the intact molecule in stimulating process outgrowth; in contrast, the 7S domain and triple helix-rich fragments of collagen IV were inactive. Moreover, anti-NC1 antiserum inhibited neuritic outgrowth on collagen IV by 79%. In long-term (up to 28 d) cultures, neurons chronically exposed to collagen IV maintained a single axon but failed to form dendrites. Thus, the NC1 domain of collagen IV can alter neuronal development by selectively stimulating axonal growth. Comparison of collagen IV's effects to those of laminin revealed that these molecules exert quantitatively different effects on the rate of initial axon growth and the number of axons extended by sympathetic neurons. Moreover, neuritic outgrowth on collagen IV, but not laminin, was blocked by cycloheximide. We also observed differences in the receptors mediating the neurite-promoting activity of these proteins. Two different antisera that recognize beta 1 integrins each blocked neuritic outgrowth on both collagen IV and laminin; however, an mAb (3A3) specific for the alpha 1 beta 1 integrin inhibited collagen IV but not laminin-induced process growth in cultures of both sympathetic and dorsal root neurons. These data suggest that immunologically distinct integrins mediate the response of peripheral neurons to collagen IV and laminin.


Assuntos
Axônios/fisiologia , Colágeno/fisiologia , Integrinas/metabolismo , Neurônios/citologia , Animais , Axônios/ultraestrutura , Divisão Celular/fisiologia , Células Cultivadas , Colágeno/metabolismo , Técnicas de Cultura , Proteínas da Matriz Extracelular/metabolismo , Imuno-Histoquímica , Laminina/metabolismo , Neurônios/ultraestrutura , Ratos , Sistema Nervoso Simpático/citologia
17.
Adolescence ; 44(176): 751-72, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20432599

RESUMO

To study changes in empathy, prosocial behavior, and school culture, 30 students were examined twice within two years.Two samples were employed to ensure a wide range of school culture perceptions; students were in a traditional high school or a Just Community School. Nonparametric bootstrap resampling methods were used to test for differences between schools and between years one and two. Just Community students perceived their school's culture as more positive than traditional high school students but no differences in empathy or prosocial behavior were found between schools. Change scores in school culture were correlated with change scores in empathy but not with prosocial behavior. This suggests that changes in empathy might require more opportunities for adolescents to exercise cognitive and emotional responsiveness in their day-to-day lives.


Assuntos
Comportamento do Adolescente , Empatia , Cultura Organizacional , Comportamento Social , Estudantes/psicologia , Adolescente , Inteligência Emocional , Feminino , Humanos , Estudos Longitudinais , Masculino , Estatísticas não Paramétricas , Estados Unidos
18.
Neuron ; 15(3): 597-605, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7546739

RESUMO

Sympathetic neurons from perinatal rat pups extend only a single axon when maintained in culture in the absence of glia and serum. Exposure to recombinant osteogenic protein-1 (OP-1) selectively induces the formation of dendrites that correctly segregate and modify cytoskeletal and membrane proteins and form synaptic contacts of appropriate polarity. OP-1 requires nerve growth factor (NGF) as a cofactor, and, in the presence of optimal concentrations of NGF, OP-1-induced dendritic growth from cultured perinatal neurons is comparable to that observed in situ. Sympathetic neuroblasts that had not formed dendrites in situ also responded to OP-1 in culture, indicating that OP-1 can cause de novo formation as well as regeneration of dendrites. These data imply that specific signals can regulate the development of neuronal shape and polarity.


Assuntos
Proteínas Morfogenéticas Ósseas , Dendritos/fisiologia , Gânglios Simpáticos/ultraestrutura , Neurônios/ultraestrutura , Proteínas/farmacologia , Fator de Crescimento Transformador beta , Animais , Animais Recém-Nascidos , Proteína Morfogenética Óssea 7 , Células CHO , Células Cultivadas , Cricetinae , Dendritos/ultraestrutura , Relação Dose-Resposta a Droga , Substâncias de Crescimento/administração & dosagem , Substâncias de Crescimento/farmacologia , Humanos , Fatores de Crescimento Neural/administração & dosagem , Fatores de Crescimento Neural/farmacologia , Proteínas/administração & dosagem , Ratos , Proteínas Recombinantes/farmacologia , Sinapses/ultraestrutura
19.
Neuron ; 5(6): 809-19, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2148487

RESUMO

We examined the subcellular distribution of specific mRNAs in cultured sympathetic neurons. Under appropriate conditions, sympathetic neurons extend both axons and dendrites that are distinguishable by light microscopic and immunocytochemical criteria. In situ hybridization revealed a differential localization of mRNA within dendrites. mRNA encoding MAP2 was abundant in cell bodies and distributed nonhomogeneously throughout the dendritic compartment, but was not detected in axons. In contrast, mRNAs encoding GAP-43 and alpha-tubulin were restricted to the cell body and largely excluded from dendrites as well as axons. Detergent extraction revealed that most dendrite-associated mRNA encoding MAP2 was associated with the Triton X-100 insoluble fraction of the cell. The subset of mRNAs present in the dendritic compartment may encode proteins involved in the morphogenesis and remodeling of dendrites.


Assuntos
Gânglios Simpáticos/ultraestrutura , Neurônios/ultraestrutura , RNA Mensageiro/análise , Animais , Células Cultivadas , Corantes , Dendritos/química , Proteína GAP-43 , Gânglios Simpáticos/embriologia , Imuno-Histoquímica , Isoquinolinas , Glicoproteínas de Membrana/análise , Glicoproteínas de Membrana/genética , Microscopia de Fluorescência , Proteínas Associadas aos Microtúbulos/análise , Proteínas Associadas aos Microtúbulos/genética , Proteínas do Tecido Nervoso/análise , Proteínas do Tecido Nervoso/genética , Hibridização de Ácido Nucleico , Sondas RNA , Ratos
20.
Bioinformatics ; 23(21): 2947-8, 2007 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-17846036

RESUMO

SUMMARY: The Clustal W and Clustal X multiple sequence alignment programs have been completely rewritten in C++. This will facilitate the further development of the alignment algorithms in the future and has allowed proper porting of the programs to the latest versions of Linux, Macintosh and Windows operating systems. AVAILABILITY: The programs can be run on-line from the EBI web server: http://www.ebi.ac.uk/tools/clustalw2. The source code and executables for Windows, Linux and Macintosh computers are available from the EBI ftp site ftp://ftp.ebi.ac.uk/pub/software/clustalw2/


Assuntos
Algoritmos , Gráficos por Computador , Alinhamento de Sequência/métodos , Análise de Sequência de Proteína/métodos , Software , Interface Usuário-Computador , Sequência de Aminoácidos , Análise por Conglomerados , Dados de Sequência Molecular , Linguagens de Programação
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