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1.
Clin Exp Allergy ; 48(5): 513-524, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29350877

RESUMO

BACKGROUND: Bronchial epithelial tight junctions (TJ) have been extensively assessed in healthy airway epithelium. However, no studies have yet assessed the effect of human rhinovirus (HRV) infection on the expression and resultant barrier function in epithelial tight junctions (TJ) in childhood asthma. OBJECTIVES: To investigate the impact of HRV infection on airway epithelial TJ expression and barrier function in airway epithelial cells (AECs) of children with and without asthma. Furthermore, to test the hypothesis that barrier integrity and function is compromised to a greater extent by HRV in AECs from asthmatic children. METHODS: Primary AECs were obtained from children with and without asthma, differentiated into air-liquid interface (ALI) cultures and infected with rhinovirus. Expression of claudin-1, occludin and zonula occluden-1 (ZO-1) was assessed via qPCR, immunocytochemistry (ICC), in-cell western (ICW) and confocal microscopy. Barrier function was assessed by transepithelial electrical resistance (TER; RT ) and permeability to fluorescent dextran. RESULTS: Basal TJ gene expression of claudin-1 and occludin was significantly upregulated in asthmatic children compared to non-asthmatics; however, no difference was seen with ZO-1. Interestingly, claudin-1, occludin and ZO-1 protein expression was significantly reduced in AEC of asthmatic children compared to non-asthmatic controls suggesting possible post-transcriptional inherent differences. HRV infection resulted in a transient dissociation of TJ and airway barrier integrity in non-asthmatic children. Although similar dissociation of TJ was observed in asthmatic children, a significant and sustained reduction in TJ expression concurrent with both a significant decrease in TER and an increase in permeability in asthmatic children was observed. CONCLUSION: This study demonstrates novel intrinsic differences in TJ gene and protein expression between AEC of children with and without asthma. Furthermore, it correlates directly the relationship between HRV infection and the resultant dissociation of epithelial TJ that causes a continued altered barrier function in children with asthma.


Assuntos
Asma/patologia , Asma/virologia , Infecções por Picornaviridae/patologia , Mucosa Respiratória/patologia , Mucosa Respiratória/virologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Rhinovirus , Junções Íntimas/patologia , Junções Íntimas/virologia
2.
Clin Exp Allergy ; 46(11): 1441-1455, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27238549

RESUMO

BACKGROUND: The airway epithelium forms an effective immune and physical barrier that is essential for protecting the lung from potentially harmful inhaled stimuli including viruses. Human rhinovirus (HRV) infection is a known trigger of asthma exacerbations, although the mechanism by which this occurs is not fully understood. OBJECTIVE: To explore the relationship between apoptotic, innate immune and inflammatory responses to HRV infection in airway epithelial cells (AECs) obtained from children with asthma and non-asthmatic controls. In addition, to test the hypothesis that aberrant repair of epithelium from asthmatics is further dysregulated by HRV infection. METHODS: Airway epithelial brushings were obtained from 39 asthmatic and 36 non-asthmatic children. Primary cultures were established and exposed to HRV1b and HRV14. Virus receptor number, virus replication and progeny release were determined. Epithelial cell apoptosis, IFN-ß production, inflammatory cytokine release and epithelial wound repair and proliferation were also measured. RESULTS: Virus proliferation and release was greater in airway epithelial cells from asthmatics but this was not related to the number of virus receptors. In epithelial cells from asthmatic children, virus infection dampened apoptosis, reduced IFN-ß production and increased inflammatory cytokine production. HRV1b infection also inhibited wound repair capacity of epithelial cells isolated from non-asthmatic children and exaggerated the defective repair response seen in epithelial cells from asthmatics. Addition of IFN-ß restored apoptosis, suppressed virus replication and improved repair of airway epithelial cells from asthmatics but did not reduce inflammatory cytokine production. CONCLUSIONS: Collectively, HRV infection delays repair and inhibits apoptotic processes in epithelial cells from non-asthmatic and asthmatic children. The delayed repair is further exaggerated in cells from asthmatic children and is only partially reversed by exogenous IFN-ß.


Assuntos
Asma/complicações , Asma/imunologia , Infecções por Picornaviridae/complicações , Mucosa Respiratória/imunologia , Mucosa Respiratória/virologia , Rhinovirus , Adolescente , Alérgenos/imunologia , Apoptose , Asma/diagnóstico , Asma/metabolismo , Proliferação de Células , Sobrevivência Celular , Criança , Pré-Escolar , Resfriado Comum , Citocinas/metabolismo , Progressão da Doença , Feminino , Humanos , Imunoglobulina E/imunologia , Mediadores da Inflamação/metabolismo , Masculino , Infecções por Picornaviridae/metabolismo , Infecções por Picornaviridae/virologia , Receptores Virais/genética , Receptores Virais/metabolismo , Mucosa Respiratória/patologia , Rhinovirus/classificação , Carga Viral , Replicação Viral
3.
Eur Respir J ; 37(3): 553-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20562125

RESUMO

Early detection of the cyanobacterium Pseudomonas aeruginosa in the lungs of young children with cystic fibrosis (CF) is considered the key to delaying chronic pulmonary disease. We investigated whether cyanide in bronchoalveolar lavage (BAL) fluid could be used as an early diagnostic biomarker of infection. Cyanide was measured in 226 BAL samples (36 P. aeruginosa infected) obtained from 96 infants and young children with CF participating in an early surveillance programme involving annual BAL. Cyanide was detected in 97.2% of P. aeruginosa infected and 60.5% of uninfected samples. Cyanide concentrations were significantly higher in BALs infected with P. aeruginosa (median (25th-75th percentile) 27.3 (22.1-33.3) µM) than those which were not (17.2 (7.85-23.0) µM, p<0.001). The best sensitivity, specificity, positive and negative predictive values were obtained with a cut-off concentration of 20.6 µM, and were 83%, 66%, 32% and 96%, respectively. Neutrophil number in BAL was a significant predictor of cyanide concentration (p<0.001). Cyanide concentration can distinguish between P. aeruginosa infected and uninfected BALs as a group, but not individually; therefore, cyanide is a poor diagnostic biomarker of P. aeruginosa infection. Cyanide levels in BAL are related to the level of neutrophilic inflammation.


Assuntos
Lavagem Broncoalveolar , Cianetos/metabolismo , Fibrose Cística/complicações , Infecções por Pseudomonas/diagnóstico , Pseudomonas aeruginosa/metabolismo , Biomarcadores/metabolismo , Calibragem , Criança , Pré-Escolar , Fibrose Cística/diagnóstico , Fibrose Cística/microbiologia , Feminino , Humanos , Lactente , Estudos Longitudinais , Pneumopatias/microbiologia , Masculino , Microscopia de Fluorescência/métodos , Neutrófilos/patologia , Valor Preditivo dos Testes , Infecções por Pseudomonas/metabolismo
4.
Child Neuropsychol ; 14(1): 71-81, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17852119

RESUMO

Twenty-seven monolingual and 27 bilingual children aged between 6 and 7 years were assessed using the core subtests of the NEPSY, a children's neuropsychological assessment. Bilingual children scored lower than monolingual children in the Language domain and their performance was comparable with the monolingual children in the domains of Attention/Executive Functioning, Sensorimotor, Visuospatial, and Memory. The NEPSY correlates well with measures of academic achievement. It is concluded that the NEPSY is relatively insensitive to cultural factors and appears to be insensitive to bilingualism in the neuropsychological assessment of bilingual children in the United Kingdom.


Assuntos
Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etnologia , Multilinguismo , Testes Neuropsicológicos , Criança , Feminino , Humanos , Masculino
5.
Free Radic Biol Med ; 31(10): 1156-62, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11705693

RESUMO

Changes in cellular reactive oxygen scavenging enzymes were assessed in suspension-derived cells of cotton (Gossypium herbaceum) cv. Dhumad following culture with a commercial bovine hemoglobin (Hb) solution (Erythrogen) at 1:100-1:1000 (v:v). Mean (+/- SEM) fresh (f.wt.) and dry weights (d.wt.) of cells after 25 d of culture were significantly (p <.05) greater in medium supplemented with 1:750 and 1:1000 (v:v) Erythrogen, compared to controls lacking Erythrogen. For example, with 1:750 (v:v) Erythrogen, mean cell f.wt. and d.wt. were increased by 45 and 31%, respectively. Total soluble cellular protein increased by 141, 176, and 191% with Erythrogen at 1:50, 1:750, and 1:1000 (v:v), respectively. Cellular catalase and glutathione reductase activities decreased significantly (p <.05) following addition of low concentrations (1:1000 and 1:750 v:v) of Erythrogen to culture medium. However, increasing the concentration of Erythrogen to a maximum of 1:100 (v:v), caused a concomitant increase in catalase to a maximum of 62% over control. Mean total superoxide dismutase activity increased linearly with increasing Erythrogen concentration, reaching a maximum mean value over 2-fold greater than control with 1:100 (v:v) Erythrogen. A similar trend was observed in cellular H2O2 content, which reached a maximum of 98% over control with 1:250 (v:v) Erythrogen. These results demonstrate that culture of cotton cells with Hb solution causes changes in cellular oxygenation sufficient to modify cellular antioxidant status.


Assuntos
Antioxidantes/metabolismo , Gossypium/citologia , Hemoglobinas/farmacologia , Animais , Catalase/metabolismo , Bovinos , Técnicas de Cultura de Células/métodos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Meios de Cultura , Glutationa Redutase/metabolismo , Gossypium/efeitos dos fármacos , Gossypium/enzimologia , Peróxido de Hidrogênio/metabolismo , Superóxido Dismutase/metabolismo
6.
J Psychiatr Res ; 32(3-4): 151-9, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9793868

RESUMO

The possible adverse clinical effects of untreated psychosis in schizophrenic patients, particularly early in the course of illness, have been a topic of considerable interest in recent years. We examined the timing of first administration of antipsychotic medication after the first onset of psychotic symptoms in 103 patients with DSM-III-R diagnoses of schizophrenia, schizophreniform or schizo-affective disorder. Patients with a delay of one or more years between the onset of the first psychotic symptom and the initiation of antipsychotic treatment demonstrated more severe negative symptomatology on admission to hospital and more severe positive symptoms and negative symptoms at discharge. These effects were present in both first-admission patients, in whom the delay to treatment immediately preceded hospitalization and chronic patients with a history of multiple hospitalizations. Patients with one or more years of untreated psychosis prior to their first antipsychotic treatment displayed a more severe poverty syndrome at the time of admission and discharge and a more severe reality distortion syndrome at discharge from the index hospitalization. These findings were not related to age, premorbid functioning, duration of illness, first- vs multiple-episodes status, or dosage of antipsychotic medication at time of admission or discharge assessment. Findings from the present study suggest that failure to initiate antipsychotic treatment early in the course of the illness may be associated with a recurrent pattern of poorer treatment response and more severe and persistent positive and negative symptomatology. These findings indicate the importance of early detection of illness and early initiation of antipsychotic treatment for the first psychotic symptoms of schizophrenia.


Assuntos
Antipsicóticos/uso terapêutico , Esquizofrenia/tratamento farmacológico , Adulto , Progressão da Doença , Feminino , Hospitalização , Hospitais Psiquiátricos , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Esquizofrenia/diagnóstico , Esquizofrenia/reabilitação , Psicologia do Esquizofrênico , Índice de Gravidade de Doença , Fatores de Tempo
7.
Clin Oncol (R Coll Radiol) ; 26(10): 636-42, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24928558

RESUMO

AIMS: To determine the pattern of disease recurrence in non-nasopharyngeal head and neck squamous cell carcinoma (HNSCC) patients treated with radical intensity-modulated radiotherapy (IMRT) with or without chemotherapy, and to correlate the sites of locoregional recurrence with radiotherapy target volumes. MATERIALS AND METHODS: In total, 136 patients treated with radical IMRT with or without chemotherapy between 2008 and 2011 for non-nasopharyngeal HNSCC were retrospectively identified. A compartmental approach to clinical target volume (CTV) delineation was routinely utilised during this period and IMRT was delivered using a 5-7 angle step and shoot technique. Locoregional recurrences were reconstructed on the planning computed tomography scan by both deformable image coregistration and by visual assessment, and were analysed in relation to target volumes and dosimetry. RESULTS: The median follow-up was 31 (range 3-53) months. Two year local control, regional control, disease-free survival, distant metastasis-free survival and overall survival were 86, 93, 78, 89 and 79%, respectively. One hundred and twenty of 136 (88%) patients achieved a complete response to treatment and 7/120 (6%) have subsequently had a locoregional recurrence. Analysis of these recurrences revealed five to be infield; one to be marginal to the high-dose CTV; one to be out-of-field. Overall the marginal/out-of-field recurrence rate was 2/136 (1.5%). CONCLUSIONS: IMRT utilising a compartmental approach to CTV delineation was associated with a low rate of marginal/out-of-field recurrence.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/radioterapia , Recidiva Local de Neoplasia/diagnóstico , Planejamento da Radioterapia Assistida por Computador , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Quimiorradioterapia , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Recidiva Local de Neoplasia/mortalidade , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Radioterapia Conformacional , Estudos Retrospectivos , Taxa de Sobrevida , Tomografia Computadorizada por Raios X , Falha de Tratamento
9.
Histochem J ; 25(10): 726-34, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8282568

RESUMO

The distribution of saccharides in pig lymph nodes, particularly on high-endothelial venule (HEV) endothelium and on lymphocytes in these vessels, was studied by examining the binding of fluorescent conjugates of 18 different lectins. Eight of the lectins, particularly with glycan specificity restricted to mannose and polyacetyllactosamine determinants, were found to bind with a high affinity to these structures. Competitive inhibition experiments revealed that polylactosamine-containing glycans were present on endothelia and lymphocytes using lectins from Lycopersicon esculentum and Solanum tuberosum, the latter lectin reacting with lymphocytes only when apparently adherent to the luminal endothelium. The The absence on pig endothelium of the Ulex europaeus binding, shown by human endothelia due to the presence of certain fucose epitopes, was confirmed. Pig lymph-node endothelium, however, bound the fucose-specific lectin of Tetragonolobus purpureas, indicating the presence of fucose on pig endothelia in a different conformation to that seen on human endothelia. The results suggested that pig lymph-node HEV endothelium expressed a core fucosylated tri- or tetra-antennary complex glycan with polylactosamine extensions and expressing an Ley determinant.


Assuntos
Endotélio Linfático/química , Linfonodos/química , Polissacarídeos/análise , Animais , Sítios de Ligação , Ligação Competitiva , Fluoresceína-5-Isotiocianato/química , Secções Congeladas , Lectinas/metabolismo , Linfonodos/metabolismo , Linfócitos/química , Microscopia de Fluorescência , Polissacarídeos/metabolismo , Suínos
10.
Hum Reprod Update ; 4(3): 213-22, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9741706

RESUMO

During 1995 and 1996 the first spermatid pregnancies were announced with both round spermatid (ROSI) and elongated spermatid (ELSI) injections. These publications were flanked by live births from ROSI in a number of animal species, with resulting offspring appearing normal, healthy and fertile. However, the live births in humans heralded a scientific and ethical debate on the clinical use of this technology; and in a number of countries nationwide moratoria prohibiting spermatid microinjection were enjoined. Concerns surrounded the biological condition of spermatids and clinical implications of utilizing an immature spermatozoon for conception. Nevertheless, case reports and a few scientific studies on human spermatid conception have been published in recent years, and further polemic on testicular histopathology and prognosis has ensued. This paper reviews the current arguments on the clinical use of ROSI and ELSI, and evaluates the biology of the main contributory components of a spermatozoon to the subsequent embryo, namely the genetic material, the microtubular organizing complex and the putative oocyte activating factor. We also consider the relevant testicular histopathology and likely outcome in the context of the current birth rate from ROSI and ICSI. We conclude by considering the way forward for infertile men who require this technology to become genetic fathers, and whether the time is now appropriate to consider clinical trials.


Assuntos
Fertilização in vitro/métodos , Infertilidade Masculina/terapia , Microinjeções , Espermátides , Ensaios Clínicos como Assunto , Feminino , Humanos , Masculino , Espermátides/ultraestrutura , Resultado do Tratamento
11.
Artigo em Inglês | MEDLINE | ID: mdl-12027228

RESUMO

Petunia hybrida cell suspension cultures were exposed to ultrasonic standing wave fields at 2.43 MHz for 40 min with mean sound pressures (within homogenous sound fields) varying from 0 (control) to ca. 1.1 MPa. Mean (+/- s.d.; n =6-9) cell viability was reduced to 87+/-10% at 0.6 MPa and to 59 +/- 23% at 1.1 MPa, compared to an initial control value of 92 +/- 6% (P <0.05). Mean (n = 3) cell alkaline phosphatase concentration increased linearly with sound pressure from a control value of 0.006+/-0.001 to 0.02+/-0.01 Sigma-Units microg(-1) protein at 1.1 MPa (P<0.05). Similarly, mean cell catalase activity increased from a control value of 0.020 +/- 0.003 to 0.026 +/- 0.008 arbitrary units at 1.1 MPa. In contrast, mean cellular lactate dehydrogenase concentration was unchanged. These observations indicate that cellular repair processes associated with increased alkaline phosphatase activity might be triggered by physical cell damage caused by ultrasound. The observed increase in catalase activity suggests increasing production of free radicals and other sonochemicals, which warrants further study. The absence of changes in lactate dehydrogenase indicates that there was no major damage to respiratory pathways or to overall cellular integrity.


Assuntos
Petunia/citologia , Ultrassom/efeitos adversos , Fosfatase Alcalina/metabolismo , Catalase/metabolismo , Sobrevivência Celular , Células Cultivadas , Ativação Enzimática , L-Lactato Desidrogenase/metabolismo , Petunia/enzimologia
12.
Plant Physiol ; 127(2): 505-16, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11598225

RESUMO

An ipt gene under control of the senescence-specific SAG12 promoter from Arabidopsis (P(SAG12)-IPT) significantly delayed developmental and postharvest leaf senescence in mature heads of transgenic lettuce (Lactuca sativa L. cv Evola) homozygous for the transgene. Apart from retardation of leaf senescence, mature, 60-d-old plants exhibited normal morphology with no significant differences in head diameter or fresh weight of leaves and roots. Induction of senescence by nitrogen starvation rapidly reduced total nitrogen, nitrate, and growth of transgenic and azygous (control) plants, but chlorophyll was retained in the lower (outer) leaves of transgenic plants. Harvested P(SAG12)-IPT heads also retained chlorophyll in their lower leaves. During later development (bolting and preflowering) of transgenic plants, the decrease in chlorophyll, total protein, and Rubisco content in leaves was abolished, resulting in a uniform distribution of these components throughout the plants. Homozygous P(SAG12)-IPT lettuce plants showed a slight delay in bolting (4-6 d), a severe delay in flowering (4-8 weeks), and premature senescence of their upper leaves. These changes correlated with significantly elevated concentrations of cytokinin and hexoses in the upper leaves of transgenic plants during later stages of development, implicating a relationship between cytokinin and hexose concentrations in senescence.


Assuntos
Alquil e Aril Transferases/genética , Proteínas de Arabidopsis/genética , Arabidopsis/genética , Cisteína Endopeptidases/genética , Lactuca/genética , Alquil e Aril Transferases/metabolismo , Apoptose , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Clorofila/biossíntese , Clorofila/metabolismo , Cisteína Endopeptidases/metabolismo , Citocininas/biossíntese , Regulação da Expressão Gênica de Plantas , Genes Reporter , Hexoses/biossíntese , Lactuca/crescimento & desenvolvimento , Compostos de Nitrogênio/metabolismo , Compostos de Nitrogênio/farmacologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/biossíntese , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , RNA de Plantas/biossíntese
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