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1.
Hum Reprod ; 36(8): 2073-2082, 2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34097020

RESUMO

STUDY QUESTION: What is the nuclear heterogeneity of high-density purified human spermatozoa typically used for IVF purposes. SUMMARY ANSWER: The data show that while density gradient separation has improved the overall sperm population, there is still a large degree of nuclear heterogeneity within these cells. WHAT IS KNOWN ALREADY: Chromomycin A3 (CMA3) is an important DNA binding fluorochrome for the assessment of male-factor fertility. It is typically used to predict IVF outcomes on entire sperm ejaculates with very high receiver operating characteristic. Here we used CMA3 to characterise typical populations of human spermatozoa that would be used for IVF purposes after density gradient separation. STUDY DESIGN, SIZE, DURATION: We compared the intensity of CMA3 binding within high-dense sperm populations obtained from men. Binding heterogeneity was confirmed through fluorescence microscopy and FACS analysis independently. We also looked at CMA3 staining directly with head morphology in this sperm population. Finally, we looked at electron micrographs of nuclear heterogeneity (vacuoles, chromatin compaction) of spermatozoa following density gradient sorting of CMA3-stained cells. PARTICIPANTS/MATERIALS, SETTING, METHODS: We used sperm donors who had fathered one or more children. Semen was collected after 2 days abstinence and purified over Percoll gradients. Only the high-quality spermatozoa, the same used for assisted conception, were then used. Cells were stained with CMA3 and sorted using FACS. Following this, electron micrographs were used to assess nuclear heterogeneity of CMA3-dependent sorted spermatozoa. MAIN RESULTS AND THE ROLE OF CHANCE: CMA3 staining occurs within morphologically normal as well as abnormal spermatozoa. High-intensity CMA3-stained sperm possessed large vacuoles that were not seen in the low-CMA3 population. In addition, the high-CMA3 stained cells possess higher amounts of nuclear granulation. LIMITATIONS, REASONS FOR CAUTION: The present study only describes the issues within the chromatin of these cells and does not suggest an alternate selection technique. WIDER IMPLICATIONS OF THE FINDINGS: CMA3 is one of the better reported prognostic assays in predicting pregnancy outcomes, especially in cases where the male is at fault. However, it is clear that even in fractionated populations of human spermatozoa, there are sperm cells that are morphologically normal yet possess high levels of CMA3 staining and chromatin granulation. The implication of this is that the embryologist, whom selects on the basis of sperm morphology, may choose a cell with poor chromatin, which may lead to poor embryo outcomes. STUDY FUNDING/COMPETING INTEREST(S): The project was funded by the National Health and Medical Research council, APP1118943. The authors have no conflict of interest to declare. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Infertilidade Masculina , Espermatozoides , Criança , Cromomicina A3 , Fertilização , Humanos , Masculino , Sêmen
2.
J Psychopharmacol ; 31(10): 1347-1361, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28925314

RESUMO

The mechanism of action of psychostimulant drugs in the treatment of Attention Deficit Hyperactivity Disorder is still largely unknown, although recent evidence suggests one possibility is that the drugs affect the superior colliculus (SC). We have previously demonstrated that systemically administered d-amphetamine attenuates/abolishes visual responses to wholefield light flashes in the superficial layers of the SC in anaesthetised rats, and the present study sought to extend this work to methylphenidate (MPH). Anaesthetised rats were administered MPH at a range of doses (or saline) and subjected to monocular wholefield light flashes at two intensities, juxta-threshold and super-threshold. In contrast to d-amphetamine, systemic MPH produced an enhancement of visual activity at both intensities. Methylphenidate was also found to produce activation of the cortical EEG in anaesthetised rats. Furthermore, cortical activation induced by electrical stimulation of the pons was found to enhance visual responses in superficial layers of the SC, and when MPH was paired with pontine-induced cortical activation, the response-enhancing effects of MPH were substantially attenuated. Taken together, the results suggest that the enhancement of visual responses in the superficial layers of the SC by MPH in the anaesthetised rat is an artefact of the drug's interaction with cortical arousal.


Assuntos
Metilfenidato/farmacologia , Colículos Superiores/efeitos dos fármacos , Anfetamina/farmacologia , Animais , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Estimulantes do Sistema Nervoso Central/farmacologia , Dextroanfetamina , Masculino , Ratos
3.
QJM ; 108(7): 527-32, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25434050

RESUMO

BACKGROUND AND AIMS: Acute tubulointerstitial nephritis (ATIN) is a potentially reversible cause of acute kidney injury with the majority of cases drug related. Our aims were to examine the incidence profile of patients with ATIN in Scotland and to assess the impact of corticosteroid treatment. DESIGN AND METHODS: All adult patients with biopsy-proven ATIN, diagnosed between 2000 and 2012, presenting to renal units serving 1.9 of Scotland's 5 million population were included. Patient demographics, presenting, aetiologic and pathologic features, treatment given and outcome were extracted from patient records. RESULTS: In total, 171 cases representing 4.7% of native renal biopsies were identified. Median serum creatinine (sCr) was 327 µmol/l at biopsy (106 µmol/l at baseline). Eosinophilia, fever or rash was present in 57% with all 3 in only 1.1%. Active urinary sediment was found in 68%. Aetiology appeared drug induced in 73%. Proton pump inhibitors (PPIs) were likely causative in almost as many cases as antibiotics (35% each) and were more frequently implicated than non-steroidal anti-inflammatory drugs (20%). Number of PPI-related cases paralleled the rising prescription of these drugs. Corticosteroids were prescribed in 59% of drug-induced ATIN (median sCr at biopsy: 356 µmol/l vs. 280 µmol/l in those managed conservatively). There was no difference in sCr at 1, 6 and 12 months, with similar proportions of both groups experiencing complete renal recovery (48% vs. 41%) and becoming dialysis dependent (10% in both). CONCLUSIONS: Incidence of biopsy-proven ATIN in Scotland has been rising over the past decade with the majority of cases drug induced. Evidence supporting corticosteroid treatment is lacking.


Assuntos
Nefrite Intersticial/epidemiologia , Idoso , Antibacterianos/efeitos adversos , Anti-Inflamatórios não Esteroides/efeitos adversos , Biópsia , Bases de Dados Factuais , Feminino , Glucocorticoides/uso terapêutico , Humanos , Incidência , Rim/patologia , Masculino , Pessoa de Meia-Idade , Nefrite Intersticial/tratamento farmacológico , Nefrite Intersticial/etiologia , Nefrite Intersticial/patologia , Inibidores da Bomba de Prótons/efeitos adversos , Escócia/epidemiologia , Resultado do Tratamento
4.
Reproduction ; 127(1): 95-103, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15056774

RESUMO

The phosphorylation of tyrosine residues in cellular proteins is a major signal transduction event during sperm capacitation. In this study protein phosphorylation was monitored using a fluorescein isothiocyanate (FITC)-labeled antiphosphotyrosine monoclonal antibody and a flow cytometric procedure optimized for sperm. Using this technique, the correlation between tyrosine phosphorylation and sperm capacitation was examined in two marsupial species, the brushtail possum and the tammar wallaby and compared with that of ram spermatozoa. The levels of tyrosine phosphorylation in sperm from all three species were increased by the addition of cyclic AMP (cAMP) and vandate, a phosphotyrosine phosphatase inhibitor and were decreased by the addition of the phosphotyrosine kinase inhibitor, staurosporine. Oviductal conditioned media (CM) induced a progressive increase in tyrosine phosphorylation in both marsupial species and also induced morphological transition from a streamlined to a 'T'-shape configuration in brushtail possum spermatozoa but not in tammar wallaby spermatozoa. Transition to the 'T'-shape orientation associated with capacitation in marsupial spermatozoa was observed by 2 h of incubation in both species when tyrosine phosphorylation was increased by higher levels of cAMP i.e. 5 mM dibutyryl cAMP plus 3 mM pentoxyphylline. Thus the tyrosine phosphorylation trigger with CM may differ in these two marsupial species. Ram sperm tyrosine phosphorylation could be increased by addition of lower levels of cAMP (1 mM). These results support the finding that tyrosine phosphorylation is associated with sperm capacitation in marsupials. Similar results were obtained by using SDS PAGE/Western blot analysis of tyrosine phosphorylation in the brushtail possum spermatozoa. The specificity, efficiency and sensitivity of the procedure described here make it applicable for routine assessment of capacitation in large numbers of samples and in other species.


Assuntos
Marsupiais/metabolismo , Transdução de Sinais/fisiologia , Capacitação Espermática/fisiologia , Espermatozoides/metabolismo , Tirosina/metabolismo , Animais , Células Cultivadas , Técnicas de Cocultura , AMP Cíclico/farmacologia , Inibidores Enzimáticos/farmacologia , Feminino , Citometria de Fluxo/métodos , Macropodidae , Masculino , Gambás , Oviductos/metabolismo , Fosforilação , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Ovinos , Estaurosporina/farmacologia , Vanadatos/farmacologia
5.
Nat Neurosci ; 5(1): 53-6, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11753416

RESUMO

Cell transplantation is one way of limiting the progress of retinal degeneration in animal models of blinding diseases such as retinitis pigmentosa (RP) and age-related macular degeneration (AMD). Here we transplanted a human retinal pigment epithelial (RPE) cell line into the subretinal space of one such model, the Royal College of Surgeons (RCS) rat, and showed, using head tracking to moving stripes and pattern discrimination in conjunction with single-unit cortical physiology, that cortically mediated vision can be preserved with this treatment.


Assuntos
Transplante de Células , Epitélio Pigmentado Ocular/citologia , Percepção Visual/fisiologia , Animais , Linhagem Celular , Modelos Animais de Doenças , Eletrofisiologia , Humanos , Neurônios/fisiologia , Epitélio Pigmentado Ocular/fisiologia , Ratos , Ratos Endogâmicos , Retina/fisiologia , Transplante Heterólogo , Testes Visuais , Córtex Visual/fisiologia
6.
Proc Natl Acad Sci U S A ; 98(17): 9942-7, 2001 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-11504951

RESUMO

Royal College of Surgeons rats are genetically predisposed to undergo significant visual loss caused by a primary dysfunction of retinal pigment epithelial (RPE) cells. By using this model, we have examined the efficacy of subretinal transplantation of two independent human RPE cell lines each exhibiting genetic modifications that confer long-term stability in vitro. The two cell lines, a spontaneously derived cell line (ARPE19) and an extensively characterized genetically engineered human RPE cell line (h1RPE7), which expresses SV40 large T (tumor) antigen, were evaluated separately. Both lines result in a significant preservation of visual function as assessed by either behavioral or physiological techniques. This attenuation of visual loss correlates with photoreceptor survival and the presence of donor cells in the areas of rescued photoreceptors at 5 months postgrafting (6 months of age). These results demonstrate the potential of genetically modified human RPE cells for ultimate application in therapeutic transplantation strategies for retinal degenerative diseases caused by RPE dysfunction.


Assuntos
Proteínas do Olho/fisiologia , Epitélio Pigmentado Ocular/transplante , Proteínas Proto-Oncogênicas , Receptores Proteína Tirosina Quinases/deficiência , Degeneração Retiniana/terapia , Animais , Antígenos Transformantes de Poliomavirus/genética , Linhagem Celular Transformada/transplante , Sobrevivência Celular , Transformação Celular Viral , Proteínas do Olho/genética , Movimentos da Cabeça/fisiologia , Humanos , Fagocitose , Epitélio Pigmentado Ocular/citologia , Ratos , Ratos Mutantes , Receptores Proteína Tirosina Quinases/genética , Degeneração Retiniana/genética , Degeneração Retiniana/patologia , Segmento Externo da Célula Bastonete/metabolismo , Segmento Externo da Célula Bastonete/patologia , Limiar Sensorial , Vírus 40 dos Símios/genética , Colículos Superiores/fisiopatologia , Transplante Heterólogo , Testes Visuais , Campos Visuais , Percepção Visual , c-Mer Tirosina Quinase
7.
Invest Ophthalmol Vis Sci ; 41(12): 3979-83, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11053302

RESUMO

PURPOSE: To apply noninvasive tests for examining visual and other sensory functions of pigmented Royal College of Surgeons (RCS) rats compared with pigmented and albino control animals. METHODS: Rats aged 3 and 7 months were tested with a general neurologic examination that assessed visual, auditory, tactile, and whisker displacement responses. Photophobic responses and visual discrimination were also measured. RESULTS: Dystrophic RCS rats failed the visual presentation tests, even at 3 months of age, and showed diminished performance on tactile tests. Auditory and whisker displacement performances were normal. Albino rats also showed diminished performance on the visual test, particularly to stimuli presented in the upper visual field. Photophobic responses were diminished in the dystrophic RCS rats compared with the pigmented control animals. Albino animals showed heightened photophobia. The dystrophic rats failed to reach criterion levels of performance on the visual discrimination test even with gratings of 0.045 cyc/deg. CONCLUSIONS: The tests used discriminate deteriorated complex visual functions in RCS rats at ages when some simple reflexes can still be demonstrated. As such, they provide easily executed tests for screening for the effects of reparative treatments such as transplantation, administration of growth factors, and gene transfer technology. The integrity of whisker and auditory function are important when using tests requiring polysensory inputs. The somatosensory defect is surprising but may be useful in searching for the gene locus of the retinal disorder. The aberrations seen in the albino rats may be attributable to the effects of light damage and unfiltered light.


Assuntos
Células Fotorreceptoras de Vertebrados/fisiologia , Degeneração Retiniana/fisiopatologia , Acuidade Visual/fisiologia , Percepção Visual/fisiologia , Animais , Fotofobia/fisiopatologia , Ratos , Ratos Mutantes , Ratos Sprague-Dawley , Limiar Sensorial , Testes Visuais
8.
Invest Ophthalmol Vis Sci ; 41(2): 518-28, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10670484

RESUMO

PURPOSE: To examine whether congenic Schwann cells grafted into the subretinal space of dystrophic Royal College of Surgeons (RCS) rats can prevent photoreceptor loss and maintain visual function. METHODS: Purified neonatal Schwann cells derived from congenic rats were grafted into the subretinal space of 3- to 4-week-old dystrophic RCS rats. Graft placement was confirmed using Schwann cells labeled in vitro with the fluorescent dye Hoechst 33342 or in grafted eyes processed for electron microscopy (48-hour to 1-month survival). At longer intervals, up to 9 months after surgery, animals were examined for photoreceptor survival; preservation of a visual reflex, head-tracking to moving stripes; and preservation of visual receptive fields associated with the region of graft placement. RESULTS: One week after the graft was performed, Schwann cells had integrated into the subretinal space with little evidence of a reactive response. When screened for head-tracking to moving stripes, Schwann cell-grafted animals performed better than sham-treated or control dystrophic animals. Threshold sensitivity measurements and visual field assessment made by recording from the superior colliculus also showed a significant level of preserved function compared with control animals. Functional rescue was correlated with photoreceptor survival and could be observed for at least 9 months after grafting. CONCLUSIONS: Schwann cells injected into the subretinal space limit functional deterioration and prolong photoreceptor survival. It is suggested that they act by local release of growth factors that either support photoreceptors directly and/or stimulate phagocytosis in RPE cells.


Assuntos
Retina/cirurgia , Degeneração Retiniana/fisiopatologia , Degeneração Retiniana/cirurgia , Células de Schwann/transplante , Animais , Comportamento Animal/fisiologia , Benzimidazóis , Transplante de Células , Eletrofisiologia , Corantes Fluorescentes , Atividade Motora/fisiologia , Células Fotorreceptoras de Vertebrados/fisiologia , Ratos , Ratos Mutantes , Retina/patologia , Retina/fisiopatologia , Degeneração Retiniana/patologia , Degeneração Retiniana/prevenção & controle , Nervo Isquiático/citologia , Colículos Superiores/fisiologia , Visão Ocular/fisiologia , Campos Visuais/fisiologia
10.
J Nurs Care Qual ; 13(2): 56-66, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9842176

RESUMO

This study reports how nurse administrators may approach an evaluation of their quality management (QM) initiative. Suggestions are based on the current study of a multiclinic health care system's QM plan. Tips on designing the evaluation and recommendations on how to report results are provided. Collaboration with local university researchers is suggested as a way to strengthen the process.


Assuntos
Sistemas Multi-Institucionais/normas , Pesquisa em Administração de Enfermagem/métodos , Ambulatório Hospitalar/normas , Avaliação de Programas e Projetos de Saúde/métodos , Gestão da Qualidade Total/normas , Grupos Focais , Conhecimentos, Atitudes e Prática em Saúde , Meio-Oeste dos Estados Unidos , Recursos Humanos em Hospital/educação , Recursos Humanos em Hospital/psicologia , Projetos de Pesquisa , Inquéritos e Questionários
11.
Nurs Adm Q ; 23(1): 29-40, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9856051

RESUMO

This study explored why nurses enjoy and seek involvement in their work. Nurses from inpatient and outpatient units were surveyed. Results indicated that prior involvement, and meaningful involvement, served to predict further teamwork. Recommendations were made to the nurse leader who wished to promote increased work involvement.


Assuntos
Relações Interprofissionais , Liderança , Recursos Humanos de Enfermagem Hospitalar/organização & administração , Supervisão de Enfermagem/organização & administração , Equipe de Assistência ao Paciente/organização & administração , Humanos , Descrição de Cargo
12.
Nurs Adm Q ; 22(3): 75-86, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9624981

RESUMO

Telemedicine is potentially an important feature of the continuum of care for the 21st century. It saves time, money, and energy for providers and patients, but is largely unreimbursed by third-party payers, and faces significant legal and attitudinal barriers. This article explores the major elements that support and hinder telemedicine as a viable option for patient care services. Barriers-reimbursement, attitudes, infrastructure, and training-must be offset by positive factors such as industry sponsorship of telemedicine equipment, positive clinical outcomes, and cost savings if implementation rates are to increase. Suggestions are made to nurse administrators who seek to pursue implementation of telemedicine technology.


Assuntos
Promoção da Saúde/organização & administração , Telemedicina/organização & administração , Continuidade da Assistência ao Paciente , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Área Carente de Assistência Médica , Medicina/estatística & dados numéricos , Enfermeiros Administradores , Especialização
13.
Brain Res Bull ; 26(1): 1-10, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2015507

RESUMO

The rodent superior colliculus mediates a wide range of physiological and behavioural responses to sudden stimuli, including desynchronisation of the cortical electroencephalogram (EEG). To investigate how this desynchronisation is produced, one of two powerful excitatory agents, sodium L-glutamate (200 nl, 10 nmol) or bicuculline methiodide (200 nl, 40 pmol), was injected into the dorsal midbrain of sleeping rats. Microinjections at sites widely distributed throughout all layers of the superior colliculus were able to desynchronise the cortical EEG. i) In the superficial layers, bicuculline was effective at more sites than glutamate, whereas the reverse was true for the deep layers. ii) At some sites EEG desynchronisation occurred together with the defensive or orienting movements that are obtained from collicular stimulation in awake animals. At other sites cortical arousal occurred without such movements. iii) Comparison with a previous study suggested that urethane selectively blocks cortical arousal to glutamate injections in the superficial and intermediate grey layers. This evidence suggests that multiple collicular output pathways can desynchronise the cortical EEG, perhaps reflecting multiple functions for EEG desynchronisation.


Assuntos
Nível de Alerta/fisiologia , Colículos Superiores/fisiologia , Animais , Nível de Alerta/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Bicuculina/análogos & derivados , Bicuculina/farmacologia , Eletroencefalografia/efeitos dos fármacos , Feminino , Masculino , Microinjeções , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiologia , Ratos , Ratos Endogâmicos , Glutamato de Sódio/farmacologia , Colículos Superiores/efeitos dos fármacos , Gravação de Videoteipe
14.
N Z Med J ; 66(414): Suppl:5-6, 1967 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-5227533
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