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1.
Sci Rep ; 14(1): 2155, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-38272959

RESUMO

In animal communication, functionally referential alarm calls elicit the same behavioral responses as their referents, despite their typically distinct bioacoustic traits. Yet the auditory forebrain in at least one songbird species, the black-capped chickadee Poecile atricapillus, responds similarly to threat calls and their referent predatory owl calls, as assessed by immediate early gene responses in the secondary auditory forebrain nuclei. Whether and where in the brain such perceptual and cognitive equivalence is processed remains to be understood in most other avian systems. Here, we studied the functional neurogenomic (non-) equivalence of acoustic threat stimuli perception by the red-winged blackbird Agelaius phoeniceus in response to the actual calls of the obligate brood parasitic brown-headed cowbird Molothrus ater and the referential anti-parasitic alarm calls of the yellow warbler Setophaga petechia, upon which the blackbird is known to eavesdrop. Using RNA-sequencing from neural tissue in the auditory lobule (primary and secondary auditory nuclei combined), in contrast to previous findings, we found significant differences in the gene expression profiles of both an immediate early gene, ZENK (egr-1), and other song-system relevant gene-products in blackbirds responding to cowbird vs. warbler calls. In turn, direct cues of threats (including conspecific intruder calls and nest-predator calls) elicited higher ZENK and other differential gene expression patterns compared to harmless heterospecific calls. These patterns are consistent with a perceptual non-equivalence in the auditory forebrain of adult male red-winged blackbirds in response to referential calls and the calls of their referents.


Assuntos
Passeriformes , Aves Canoras , Animais , Masculino , Vocalização Animal/fisiologia , Aves Canoras/fisiologia , Prosencéfalo/fisiologia , Transcriptoma , Percepção Auditiva/fisiologia
2.
The Nigerian Health Journal ; 23(3): 837-843, 2023. tables, figures
Artigo em Inglês | AIM (África) | ID: biblio-1512115

RESUMO

Antimicrobial resistance remains a threat to patient safety and healthcare outcomes and largely arises from inappropriate antimicrobial prescriptions. This study aimed to determine the pattern of antibiotic prescriptions in the Paediatrics department of Rivers State University Teaching Hospital, Port Harcourt.Method:A point prevalence survey was conducted in the Paediatric wards and Special Care Baby Unit (SCBU) on 13 November 2021. Records of all children admitted before or at 8:00a.m. on the day of the survey were descriptively analysed using the protocol and web-based management system of the Global Point Prevalence Survey of Antimicrobial Consumption and Resistance, University of Antwerp.Results: The antibiotic prevalence in this study was 77.4%. The most common indication(s) for antibiotic use in SCBU was infection prophylaxis (81.3%) and in paediatric wards: Pneumonia, Ear Nose Throat and Soft tissue infections accounted for (23.1%) each. Third-generation cephalosporins and aminoglycosides were predominantly used in all wards and were empirical-based prescriptions. Regarding antibiotic quality indicators of prescriptions: In SCBU: 19 (90.5%) had indication(s) for antibiotics documented, 10 (46.7%) were guideline compliant, and 1 (4.8%) had documented review/stop date. In the paediatric medical and surgical wards, 17(85.0%) vs. 4(100%) had indication(s) for antibiotics documented, 6(30.0%) vs. 0(0%) were guideline compliant, and 1(5.0%) vs. 4(100.0%) had a review/ stop date.Conclusion:High prevalence of antibiotic use, suboptimal antibiotic quality indicators and absence of laboratory evidence for antibiotic prescriptions were observed in the paediatric units. There is a need to reorientate prescribers and institute strategic measures to improve antimicrobial stewardship


Assuntos
Humanos , Gestão de Antimicrobianos , Antibacterianos , Prescrições , Pediatria Integrativa , Infecções
3.
Braz J Biol ; 82: e264475, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36169529

RESUMO

The sucking insect, Glycaspis brimblecombei Moore (Hemiptera: Aphalaridae), is originally from Australia and reduces the productivity of Eucalyptus crops. The parasitoid Psyllaephagus bliteus Riek (Hymenoptera: Encyrtidae) is the main agent used in the integrated management of G. brimblecombei. Endosymbionts, in insects, are important in the adaptation and protection of their hosts to the environment. The intracellular symbionts Wolbachia, induces reproductive changes such as cytoplasmic incompatibility, feminization, male death and parthenogenesis. The objective of this study was to report the first record of Wolbachia pipientis in populations of G. brimblecombei and of its parasitoid P. bliteus in the field in Brazil. Branches with adults of G. brimblecombei and P. bliteus were collected from eucalyptus trees in commercial farms in six Brazilian states and, after emergence, the insects obtained were frozen at -20 °C. Polymerase chain reaction (PCR) was performed to detect the Wolbachia endosymbiont. Wolbachia pipientis was identified in individuals of G. brimblecombei and its parasitoid P. bliteus from populations of the counties of Agudos and Mogi-Guaçu (São Paulo State), Itamarandiba (Minas Gerais State) and São Jerônimo da Serra (Paraná State) in Brazil.


Assuntos
Eucalyptus , Hemípteros , Himenópteros , Wolbachia , Animais , Brasil , Humanos
4.
RSC Adv ; 10(42): 25116-25124, 2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35517431

RESUMO

The synthesis of a palladium-containing iodovanadinite derivative, hypothetically "PdPb9(VO4)6I2", was attempted using PdI2 as a source of iodine in searching for a novel waste form for radioiodine. Stoichiometric amounts of Pb3(VO4)2 and PdI2 were batched and reacted at elevated temperatures in sealed vessels. Batched material was also subjected to high-energy ball-milling (HEBM) in order to reduce reaction time and the potential for iodine volatilization during subsequent reaction at 200-500 °C. The resulting products were characterized using X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray analysis, IR spectroscopy, thermal analysis and Pd K XANES. Results showed that PdI2 can function as a sacrificial iodine source for the formation of iodovanadinite, prototypically Pb10(VO4)6I2, however, the incorporation of Pd into this phase was not definitively observed. The sacrificial reaction mechanism involved the decomposition of PdI2 to Pd metal and nascent I2, with the latter incorporated into the iodovanadinite Pb10(VO4)6I2 phase. In comparison to processing using standard solid state reaction techniques, the use of HEBM prior to high temperature reaction generates a more homogeneous end-product with better iodine retention for this system. Overall, the key novelty and importance of this work is in demonstrating a method for direct immobilisation of undissolved PdI2 from nuclear fuel reprocessing, in a composite wasteform in which I-129 is immobilised within a durable iodovandinite ceramic, encapsulating Pd metal.

5.
Artigo em Francês | AIM (África) | ID: biblio-1264232

RESUMO

Les adénopathies cervicales chroniques sont celles qui évoluent depuis plus de trois semaines de façon non résolutive. Elles posent un problème de diagnostic étiologique et peuvent annoncer une affection grave. Matériel et méthodes : Il s'est agi d'une étude descriptive et rétrospective allant du 01 juillet 2007 au 31 juillet 2017, soit une période de 10ans. Cette étude s'est déroulée dans les services d'ORL du CHU-B et de l'Hôpital Général Adolphe SICE. Résultats : Au total 100 cas d'adénopathies cervicales chroniques ont été colligés en 10 ans, soit une prévalence de 1,8%. Le sex-ratio était de 1,17 et la tranche d'âge la plus représentée était celle de 20 à 29 ans avec une moyenne d'âge de 30,8±15,8 ans. La plupart des patients avaient une poly-adénopathie cervicale et une fièvre comme signe associé (64% des cas). Les lésions histopathologiques en cause étaient la tuberculose ganglionnaire (49%), les lymphomes ganglionnaires (21%), les adénites réactionnelles (15%), les métastases des carcinomes (11%) l'histiocytose ganglionnaire (2%) et la maladie de CASTLEMAN (2%).Conclusion : La pathologie ganglionnaire cervicale au Congo reste dominée par la tuberculose, suivie des proliférations lymphoïdes malignes et réactionnelles. L'examen anatomo-pathologique standard est complété par une étude immunohistochimique pour un diagnostic étiologique plus précis


Assuntos
Congo , Imuno-Histoquímica , Linfadenopatia/diagnóstico , Linfadenopatia/epidemiologia , Pescoço
6.
Bone Marrow Transplant ; 52(6): 825-831, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28218757

RESUMO

We report outcomes for 44 children who underwent stem cell transplantation (SCT) for refractory AML in the UK between 2000 and 2012. Median age at SCT was 11.5 years. Twenty-three patients had primary refractory and 21 relapsed refractory AML. Refractory disease was confirmed by cytogenetics/molecular genetics in 24 cases. Median follow-up of the whole cohort is 6.8 years (2.1-14.9 years). Thirty patients (68%) achieved a CR following SCT. Transplant-related mortality at 1 year was 18%. Acute GVHD incidence was 52% (grade ⩾III 19%), chronic 7%. Relapse was the major cause of treatment failure and occurred in 32% of patients at a median of 61 days post SCT. Five-year overall survival and leukemia-free survival (LFS) were 43% (95% CI 31-61%). All patients with favorable cytogenetics (n=6) are alive in CR. Outcomes in patients with primary refractory disease were equivalent to those with relapsed refractory AML. Blast percentage ⩽30% in the BM pre-SCT, myeloablative conditioning and acute GVHD proved to be favorable prognostic features. We could stratify patients according to age ⩾10 years and >30% blasts in BM pre-SCT. Patients with none/one of these risk factors were highly salvageable (5 years LFS 53%) whereas those with both factors had a very poor prognosis (5 years LFS 10%). This may facilitate decision making on whether it is appropriate to consider transplant in such patients.


Assuntos
Doença Enxerto-Hospedeiro/mortalidade , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/terapia , Doença Aguda , Adolescente , Aloenxertos , Criança , Pré-Escolar , Aberrações Cromossômicas , Intervalo Livre de Doença , Feminino , Seguimentos , Doença Enxerto-Hospedeiro/genética , Doença Enxerto-Hospedeiro/patologia , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Masculino , Recidiva , Taxa de Sobrevida , Reino Unido/epidemiologia
7.
J Mol Cell Cardiol ; 104: 31-42, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28111173

RESUMO

BACKGROUND: Three distinct Ca2+ release channels were identified in dog P-cells: the ryanodine receptor subtype 2 (RyR2) was detected throughout the cell, while the ryanodine receptor subtype 3 (RyR3) and inositol phosphate sensitive Ca2+ release channel (InsP3R) were found in the cell periphery. How each of these channels contributes to the Ca2+ cycling of P-cells is unclear. Recent modeling of Ca2+ mobilization in P-cells suggested that Ca2+ sensitivity of Ca2+induced Ca2+release (CICR) was larger at the P-cell periphery. Our study examined whether this numerically predicted region of Ca2+ release exists in live P-cells. We compared the regional Ca2+ dynamics with the arrangement of intracellular Ca2+ release (CR) channels. METHODS: Gene expression of CR channels was measured by qPCR in Purkinje fibers and myocardium of adult Yucatan pig hearts. We characterized the CR channels protein expression in isolated P-cells by immuno-fluorescence, laser scanning confocal microscopy, and 3D reconstruction. The spontaneous Ca2+ activity and electrically-evoked Ca2+ mobilization were imaged by 2D spinning disk confocal microscopy. Functional regions of P-cell were differentiated by the characteristics of local Ca2+ events. We used the Ca2+ propagation velocities as indicators of channel Ca2+ sensitivity. RESULTS: RyR2 gene expression was identical in Purkinje fibers and myocardium (6 hearts) while RyR3 and InsP3R gene expressions were, respectively, 100 and 16 times larger in the Purkinje fibers. Specific fluorescent immuno-staining of Ca2+ release channels revealed an intermediate layer of RyR3 expression between a near-membrane InsP3R-region and a central RyR2-region. We found that cell periphery produced two distinct forms of spontaneous Ca2+-transients: (1) large asymmetrical Ca2+ sparks under the membrane, and (2) typical Ca2+-wavelets propagating exclusively around the core of the cell. Larger cell-wide Ca2+ waves (CWWs) appeared occasionally traveling in the longitudinal direction through the core of Pcells. Large sparks arose in a micrometric space overlapping the InsP3R expression. The InsP3R antagonists 2-aminoethoxydiphenyl borate (2-APB; 3µM) and xestospongin C (XeC; 50µM) dramatically reduced their frequency. The Ca2+ wavelets propagated in a 5-10µm thick layered space which matched the intermediate zone of RyR3 expression. The wavelet incidence was unchanged by 2-APB or XeC, but was reduced by 60% in presence of the RyR3 antagonist dantrolene (10µM). The velocity of wavelets was two times larger (86±16µm/s; n=14) compared to CWWs' (46±10µm/s; n=11; P<0.05). Electric stimulation triggered a uniform and large elevation of Ca2+ concentration under the membrane which preceded the propagation of Ca2+ into the interior of the cell. Elevated Cai propagated at 150µm/s (147±34µm/s; n=5) through the region equivalent to the zone of RyR3 expression. This velocity dropped by 50% (75±24µm/s; n=5) in the central region wherein predominant RyR2 expression was detected. CONCLUSION: We identified two layers of distinct Ca2+ release channels in the periphery of Pcell: an outer layer of InsP3Rs under the membrane and an inner layer of RyR3s. The propagation of Ca2+ events in these layers revealed that Ca2+ sensitivity of Ca2+ release was larger in the RyR3 layer compared to that of other sub-cellular regions. We propose that RyR3 expression in P-cells plays a role in the stability of electric function of Purkinje fibers.


Assuntos
Sinalização do Cálcio , Cálcio/metabolismo , Miocárdio/metabolismo , Ramos Subendocárdicos/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Potenciais de Ação , Animais , Canais de Cálcio/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Retículo Sarcoplasmático/metabolismo , Suínos
8.
Virus Res ; 226: 60-70, 2016 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-27189041

RESUMO

Porcine epidemic diarrhea virus (PEDV) is the causative agent of an acute, highly contagious, and severe enteric disease that leads to high mortality rates in suckling piglets. Therefore, accurate diagnosis of PEDV infection is critical for the implementation of control measures for the virus. Many diagnostic tests have been recently developed and are currently available for the detection of PEDV, its proteins or nucleic acid, including virus isolation, immunofluorescence (IF) or immunohistochemistry (IHC), polymerase chain reaction (PCR) and isothermal amplification assays. Additionally, several serological assays have been developed and are currently used for the detection of antibodies against PEDV. Molecular assays such as real-time reverse transcriptase-PCR (rRT-PCR) became the methods of choice for the diagnosis of PEDV infection, providing sensitive, specific and rapid detection of the virus RNA in clinical samples. Whereas serological assays have been widely used to monitor prior exposure to the virus and to evaluate the efficacy of novel vaccine candidates or vaccination strategies. Here we discuss the properties of current PEDV diagnostic assays and prospects for improving diagnostic strategies in the future.


Assuntos
Infecções por Coronavirus/veterinária , Vírus da Diarreia Epidêmica Suína/genética , Vírus da Diarreia Epidêmica Suína/imunologia , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/virologia , Animais , Interações Hospedeiro-Patógeno/imunologia , Técnicas de Diagnóstico Molecular , Reação em Cadeia da Polimerase/métodos , Vírus da Diarreia Epidêmica Suína/classificação , Vírus da Diarreia Epidêmica Suína/isolamento & purificação , Testes Sorológicos , Suínos , Doenças dos Suínos/imunologia
9.
Cogn Neuropsychiatry ; 21(2): 107-15, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26835899

RESUMO

INTRODUCTION: This study examined the relationship between ideas and delusions of reference (I/DOR) and attentional shift to a self-referential stimulus (subject's own name, SON). METHODS: Psychotic patients with I/DOR (n = 20) and without I/DOR (n = 17) matched for age and education were tested for attentional shift to SON embedded in a background voice clip presented binaurally when engaging in an attention-demanding task (computerised Stroop task). Reaction time and accuracy in Stroop tasks with and without embedded SON were measured. I/DOR severity, other positive symptoms, negative symptoms and cognitive performance were assessed. RESULTS: There was significant interaction between conditions (Stroop tasks with and without SON) and groups (patients with and without I/DOR) on reaction time (F(1,32) = 4.22, p = .05). Simple main effects showed a significant mean difference in reaction time between conditions in patients with I/DOR (107.7 milliseconds, p = .001) but not in those without (5.8 milliseconds, p = .86). Within-subject difference in reaction time correlated with I/DOR severity scores (r = .33-.52, range; p < .05) and remained significant after controlling for other clinical and cognitive variables. CONCLUSIONS: The significant interaction and simple main effect suggest that I/DOR are associated with a heightened attentional shift to SON. The SON paradigm can potentially be developed into a neurocognitive parameter of I/DOR. However, the lack of non-self stimuli in the SON paradigm limits the interpretation on whether I/DOR are associated with general or specific distractibility related to self-referential information and further studies are warranted.


Assuntos
Atenção , Delusões/psicologia , Transtornos Psicóticos/psicologia , Esquizofrenia , Psicologia do Esquizofrênico , Adolescente , Adulto , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Masculino , Tempo de Reação , Pensamento , Adulto Jovem
10.
J Public Health (Oxf) ; 38(2): 197-205, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-25774056

RESUMO

BACKGROUND: The implementation of the 'Removal of the Spare Room Subsidy' in April 2013, commonly known as the 'bedroom tax', affects an estimated 660 000 working age social housing tenants in the UK, reducing weekly incomes by £12-£22. This study aimed to examine the impact of this tax on health and wellbeing in a North East England community in which 68.5% of residents live in social housing. METHODS: Qualitative study using interviews and a focus group with 38 social housing tenants and 12 service providers. RESULTS: Income reduction affected purchasing power for essentials, particularly food and utilities. Participants recounted negative impacts on mental health, family relationships and community networks. The hardship and debt that people experienced adversely affected their social relationships and ability to carry out normal social roles. Residents and service providers highlighted negative impacts on the neighbourhood, as well as added pressure on already strained local services. CONCLUSIONS: The bedroom tax has increased poverty and had broad-ranging adverse effects on health, wellbeing and social relationships within this community. These findings strengthen the arguments for revoking this tax.


Assuntos
Renda , Relações Interpessoais , Pobreza , Comportamento Social , Impostos , Adulto , Idoso , Idoso de 80 Anos ou mais , Dieta , Inglaterra , Feminino , Nível de Saúde , Habitação , Humanos , Entrevistas como Assunto , Masculino , Saúde Mental , Pessoa de Meia-Idade , Pobreza/economia , Pobreza/psicologia , Habitação Popular , Apoio Social , Fatores Socioeconômicos , Impostos/economia , Reino Unido , Adulto Jovem
11.
Indoor Air ; 26(2): 219-30, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25788118

RESUMO

This study characterized indoor volatile organic compounds (VOCs) and investigated the effects of the dwelling characteristics, building materials, occupant activities, and environmental conditions on indoor VOC concentrations in 40 dwellings located in Melbourne, Australia, in 2008 and 2009. A total of 97 VOCs were identified. Nine VOCs, n-butane, 2-methylbutane, toluene, formaldehyde, acetaldehyde, d-limonene, ethanol, 2-propanol, and acetic acid, accounted for 68% of the sum of all VOCs. The median indoor concentrations of all VOCs were greater than those measured outdoors. The occupant density was positively associated with indoor VOC concentrations via occupant activities, including respiration and combustion. Terpenes were associated with the use of household cleaning and laundry products. A petroleum-like indoor VOC signature of alkanes and aromatics was associated with the proximity of major roads. The indoor VOC concentrations were negatively correlated (P < 0.05) with ventilation. Levels of VOCs in these Australian dwellings were lower than those from previous studies in North America and Europe, probably due to a combination of an ongoing temporal decrease in indoor VOC concentrations and the leakier nature of Australian dwellings.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental , Compostos Orgânicos Voláteis/análise , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Austrália , Butanos , Cicloexenos , Formaldeído , Habitação , Limoneno , Pentanos , Terpenos , Ventilação
12.
Br J Dermatol ; 170(3): 599-608, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24116897

RESUMO

BACKGROUND: Primary cutaneous T-cell lymphoma (CTCL) is progressive, can cause significant symptoms, and impacts on quality of life. Therefore supportive and palliative care might have a role in the care of patients and families. OBJECTIVES: To identify and appraise the available peer-reviewed evidence on the supportive and palliative care needs of patients and their caregivers. METHODS: A systematic review of the literature was conducted. Extracted data from eligible papers were collated in themes relating to supportive and palliative care needs and outcomes for patients, informal caregivers, health professionals and reported service models. RESULTS: Eighteen retained papers reported a symptom or quality-of-life measure. Five reported only these measures, 13 reported outcomes in relation to an intervention. Systemic therapy targeted at disease remission was the most commonly reported intervention (12/13). No quality-of-life tool was consistently used. Pruritus was frequently reported as an outcome (n = 9) often using the visual analogue scale, VAS itch. Psychosocial, spiritual and caregiver needs were reported infrequently or not at all. CONCLUSIONS: No measure is routinely used to measure supportive and palliative care outcomes in CTCL. Physical needs, particularly pruritus, were reported commonly; however, qualitative evidence of experience is limited. Caregivers' needs are rarely explored. To compare outcomes from clinical studies, a single multidimensional tool used in routine practice would be useful. Further work is needed to explore a model of service that meets the specific physical, psychosocial and spiritual needs of this group of patients and their carers.


Assuntos
Cuidadores/psicologia , Linfoma Cutâneo de Células T/terapia , Cuidados Paliativos/normas , Neoplasias Cutâneas/terapia , Humanos , Linfoma Cutâneo de Células T/psicologia , Avaliação das Necessidades , Avaliação de Resultados da Assistência ao Paciente , Prurido/etiologia , Qualidade de Vida , Neoplasias Cutâneas/psicologia , Apoio Social , Espiritualidade
13.
Rev Sci Instrum ; 84(8): 086108, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24007128

RESUMO

An algorithm was developed to convert radiation intensity images acquired using a black and white CCD camera to thermal images without requiring knowledge of incident background radiation. This unique infrared (IR) thermography method was developed to determine aerothermal characteristics of advanced cooling concepts for gas turbine cooling application. Compared to IR imaging systems traditionally used for gas turbine temperature monitoring, the system developed for the current study is relatively inexpensive and does not require calibration with surface mounted thermocouples.

14.
J Physiol ; 591(17): 4301-19, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23897231

RESUMO

Despite strong suspicion that abnormal Ca(2+) handling in Purkinje cells (P-cells) is implicated in life-threatening forms of ventricular tachycardias, the mechanism underlying the Ca(2+) cycling of these cells under normal conditions is still unclear. There is mounting evidence that P-cells have a unique Ca(2+) handling system. Notably complex spontaneous Ca(2+) activity was previously recorded in canine P-cells and was explained by a mechanistic hypothesis involving a triple layered system of Ca(2+) release channels. Here we examined the validity of this hypothesis for the electrically evoked Ca(2+) transient which was shown, in the dog and rabbit, to occur progressively from the periphery to the interior of the cell. To do so, the hypothesis was incorporated in a model of intracellular Ca(2+) dynamics which was then used to reproduce numerically the Ca(2+) activity of P-cells under stimulated conditions. The modelling was thus performed through a 2D computational array that encompassed three distinct Ca(2+) release nodes arranged, respectively, into three consecutive adjacent regions. A system of partial differential equations (PDEs) expressed numerically the principal cellular functions that modulate the local cytosolic Ca(2+) concentration (Cai). The apparent node-to-node progression of elevated Cai was obtained by combining Ca(2+) diffusion and 'Ca(2+)-induced Ca(2+) release'. To provide the modelling with a reliable experimental reference, we first re-examined the Ca(2+) mobilization in swine stimulated P-cells by 2D confocal microscopy. As reported earlier for the dog and rabbit, a centripetal Ca(2+) transient was readily visible in 22 stimulated P-cells from six adult Yucatan swine hearts (pacing rate: 0.1 Hz; pulse duration: 25 ms, pulse amplitude: 10% above threshold; 1 mm Ca(2+); 35°C; pH 7.3). An accurate replication of the observed centripetal Ca(2+) propagation was generated by the model for four representative cell examples and confirmed by statistical comparisons of simulations against cell data. Selective inactivation of Ca(2+) release regions of the computational array showed that an intermediate layer of Ca(2+) release nodes with an ~30-40% lower Ca(2+) activation threshold was required to reproduce the phenomenon. Our computational analysis was therefore fully consistent with the activation of a triple layered system of Ca(2+) release channels as a mechanism of centripetal Ca(2+) signalling in P-cells. Moreover, the model clearly indicated that the intermediate Ca(2+) release layer with increased sensitivity for Ca(2+) plays an important role in the specific intracellular Ca(2+) mobilization of Purkinje fibres and could therefore be a relevant determinant of cardiac conduction.


Assuntos
Sinalização do Cálcio , Modelos Cardiovasculares , Ramos Subendocárdicos/metabolismo , Animais , Canais de Cálcio/metabolismo , Citoplasma/metabolismo , Difusão , Retículo Endoplasmático/metabolismo , Suínos , Porco Miniatura
15.
J Physiol ; 590(19): 4691-705, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22753545

RESUMO

The hyperpolarization-activated current (I(h)) has been implicated in nociception/pain, but its expression levels in nociceptors remained unknown. We recorded I(h) magnitude and properties by voltage clamp from dorsal root ganglion (DRG) neurons in vivo, after classifying them as nociceptive or low-threshold-mechanoreceptors (LTMs) and as having C-, Aδ- or Aα/ß-conduction velocities (CVs). For both nociceptors andLTMs, I(h) amplitude and I(h) density (at -100 mV) were significantly positively correlated with CV.Median I(h) magnitudes and I(h) density in neuronal subgroupswere respectively:muscle spindle afferents(MSAs):-4.6 nA,-33 pA pF(-1); cutaneous Aα/ß LTMs: -2.2 nA, -20 pA pF(-1); Aß-nociceptors: -2.6 nA, -21 pA pF(-1); both Aδ-LTMs and nociceptors: -1.3 nA, ∼-14 pA pF(-1); C-LTMs: -0.4 nA, -7.6 pA pF(-1); and C-nociceptors: -0.26 nA, -5 pApF(-1). I(h) activation slow time constants (slow τ values) were strongly correlated with fast τ values; both were shortest in MSAs. Most neurons had τ values consistent with HCN1-related I(h); others had τ values closer to HCN1+HCN2 channels, or HCN2 in the presence of cAMP. In contrast, median half-activation voltages (V(0.5)) of -80 to -86 mV for neuronal subgroups suggest contributions of HCN2 to I(h). τ values were unrelated to CV but were inversely correlated with I(h) and I(h) density for all non-MSA LTMs, and for Aδ-nociceptors. From activation curves ∼2-7% of I(h)would be activated at normal membrane potentials. The high I(h) may be important for excitability of A-nociceptors (responsible for sharp/pricking-type pain) and Aα/ß-LTMs (tactile sensations and proprioception). Underlying HCN expression in these subgroups therefore needs to be determined. Altered high I(h) may be important for excitability of A-nociceptors (responsible for sharp/pricking-type pain) and Aα/ß-LTMs (tactile sensations and proprioception). Underlying HCN expression in these subgroups therefore needs to be determined. Altered Ih expression and/or properties (e.g. in chronic/pathological pain states) may influence both nociceptor and LTM excitability.expression and/or properties (e.g. in chronic/pathological pain states) may influence both nociceptor and LTM excitability.


Assuntos
Canais de Cátion Regulados por Nucleotídeos Cíclicos/fisiologia , Gânglios Espinais/fisiologia , Canais Iônicos/fisiologia , Canais de Potássio/fisiologia , Potenciais de Ação/fisiologia , Animais , Feminino , Gânglios Espinais/efeitos dos fármacos , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização , Nociceptores/fisiologia , Dor/fisiopatologia , Pirimidinas/farmacologia , Ratos , Ratos Wistar
16.
J Fr Ophtalmol ; 35(8): 626.e1-4, 2012 Oct.
Artigo em Francês | MEDLINE | ID: mdl-22673047

RESUMO

In childhood, benign tumors are uncommon causes of exophtalmos. We report a case of intraorbital lipofibroma in an 11-year-old girl who presented with painless, progressive proptosis of the right eye over the preceding 6 months. Ultrasound had shown an extraconal intraorbital mass. Complete excision and pathologic examination were performed, revealing a lipofibroma with no signs of malignancy This case report is notable due to the rarity of the condition.


Assuntos
Exoftalmia/etiologia , Exoftalmia/terapia , Neoplasias Oculares/complicações , Neoplasias Oculares/terapia , Fibroma/complicações , Fibroma/terapia , Criança , Exoftalmia/diagnóstico , Neoplasias Oculares/diagnóstico , Feminino , Fibroma/diagnóstico , Hospitais de Ensino , Humanos , Lipoma/complicações , Lipoma/diagnóstico , Lipoma/terapia , Neoplasias Complexas Mistas/complicações , Neoplasias Complexas Mistas/diagnóstico , Neoplasias Complexas Mistas/terapia , Procedimentos Cirúrgicos Oftalmológicos , Órbita/patologia , Órbita/cirurgia , Togo
17.
Osteoarthritis Cartilage ; 20(4): 305-13, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22285737

RESUMO

OBJECTIVE: Osteoarthritis (OA) pain mechanisms are poorly understood. We used the monosodium iodoacetate (MIA) model of knee OA to characterize changes in excitability during the course of OA in different classes of mechanosensitive afferents projecting to joint-associated tissues, and examine whether these afferent responses and pain behavior are correlated. METHODS: Rats were injected intra-articularly with MIA (1mg in 50 µl). Hind-limb weight bearing was studied 3 (MIA3) and 14 (MIA14) days after MIA, followed by deep anesthesia and teased-nerve-fiber recordings. Spontaneous activity (SA) and mechanically evoked responses of A- and C-mechanosensitive fibers (AM and CM respectively, probably nociceptive) innervating tissues associated with the ipsilateral knee joint were examined. RESULTS: MIA3 and MIA14 rats exhibited reduced ipsilateral weight bearing. SA (>0.02 impulses/s) occurred in ∼50% of CMs from MIA rats vs 0% in normals. SA firing rates in CMs were significantly higher than normal; decreased weight bearing was correlated with increased CM SA rates. Neither percentages of AMs with SA (20%) nor their firing rates (0-0.01 impulses/s) significantly increased after MIA. In contrast, in MIA rats AMs, but not CMs, exhibited decreased mechanical thresholds and increased firing rates in response to suprathreshold mechanical stimulation. CONCLUSIONS: These findings of increased SA firing rate in CMs but not AMs and increased mechanical sensitivity of AMs, but not CMs, have not previously been reported. These are two distinct important physiological mechanisms that may underpin spontaneous pain (CMs) and stimulus-evoked pain (AMs) in OA. Our data contribute to a mechanism-based understanding of OA pain.


Assuntos
Artrite Experimental/fisiopatologia , Fibras Nervosas Mielinizadas/fisiologia , Fibras Nervosas Amielínicas/fisiologia , Neurônios Aferentes/fisiologia , Osteoartrite/fisiopatologia , Animais , Artrite Experimental/induzido quimicamente , Artrite Experimental/complicações , Artrite Experimental/patologia , Iodoacetatos , Articulações/inervação , Articulações/patologia , Masculino , Mecanorreceptores/fisiologia , Mecanotransdução Celular/fisiologia , Condução Nervosa/fisiologia , Osteoartrite/induzido quimicamente , Osteoartrite/complicações , Osteoartrite/patologia , Dor/etiologia , Dor/fisiopatologia , Ratos , Ratos Wistar , Suporte de Carga
18.
Bull Soc Belge Ophtalmol ; (318): 11-7, 2011.
Artigo em Francês | MEDLINE | ID: mdl-22003759

RESUMO

AIM: To point out the importance of the early diagnosis of giant cell arteritis (GCA) (Horton's disease). MATERIALS AND METHODS: a case report of a sudden bilateral blindness that had revealed GCA. CASE REPORT: A 68-year old female patient with a history of elevated blood pressure and diabetes mellitus type 2, was examined in emergency for a right painful headache developed one week previously. In ophthalmological examination, her BCVA was 0.9 and P2 in both eyes. Diagnosis of Horton's disease was not initially done in spite of elevated erythrocytes sedimentation rate (ESR) at 30 mm, protein C reactive (CRP) at 19 mg/l. The patient consulted seven weeks later in emergency for a sudden bilateral blindness associated with severe headache, recent asthenia, and limping of the lower jaw. At that time, visual acuity was reduced to light perception in both eyes whereas ophthalmoscopy revealed a bilateral central retinal artery occlusion (CRAO). ESR was 74 mm and CRP 233 mg/I. Temporal artery biopsy confirmed the diagnosis of GCA. The patient was treated with systemic steroids without visual recovery. CONCLUSION: This case outlines the importance of the early diagnosis of GCA in order to make possible to start treatment before the occurrence of irreversible complications.


Assuntos
Arterite de Células Gigantes/diagnóstico , Arterite de Células Gigantes/patologia , Idoso , Biópsia , Diabetes Mellitus Tipo 2/complicações , Diagnóstico Precoce , Feminino , Arterite de Células Gigantes/complicações , Humanos , Oclusão da Artéria Retiniana/etiologia
19.
Perfusion ; 26(4): 302-7; discussion 308, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21593087

RESUMO

A 4.3 kg, three-month-old patient, diagnosed with a perimembranous ventricular septal defect, presented for cardiac surgery. Upon initiation of cardiopulmonary bypass (CPB), the patient developed carboxyhemoglobinemia (11.1%). Potential sources for the unexpected acquired carboxyhemoglobinemia were sought quickly. Testing of residual blood from the unit of packed red blood cells (PRBCs) used to prime the CPB circuit revealed a carboxyhemoglobin (COHb) of 15.1 %. A decrease in cerebral oximetry (rSO(2)) on CPB was initially felt to be a result of the elevated COHb levels. When ventilation of the oxygenator with 100% oxygen (O(2)) failed to decrease COHb levels, a partial exchange transfusion was performed with reduction in COHb to 7.1%. The operation was completed successfully and the patient's COHb levels returned to normal within 75 minutes. Post case analysis of events and data collected during the case revealed a broader differential for explaining the compromised patient's O(2) delivery than the transient acquired carboxyhemoglobinemia. A partial obstruction of the superior vena cava could have triggered the drop in rSO(2) on CPB. Follow-up of the donor blood confirmed the donor had previously undiagnosed carboxyhemoglobinemia as a result of chronic carbon monoxide exposure from a faulty vehicle exhaust system.


Assuntos
Doadores de Sangue , Monóxido de Carbono/efeitos adversos , Carboxihemoglobina/análise , Ponte Cardiopulmonar , Comunicação Interventricular/cirurgia , Oximetria , Humanos , Lactente , Masculino , Oxigênio/metabolismo
20.
Eur Ann Otorhinolaryngol Head Neck Dis ; 127(6): 217-20, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21051307

RESUMO

INTRODUCTION: Ossifying fibroma of the jaw is a benign tumorous disease, somewhat rare and aggressive. It frequently targets the mandible, but seldom the maxillary. CASE STUDY: The present study reports the first case of left maxillary sinus fibroma treated at the Kara Teaching Hospital in North Togo. It occurred in a 29-year-old patient who experienced slow-growing tumefaction of the left maxillary sinus, resulting in deformation of the left side of the face in the maxillary region and ipsilateral nasal obstruction. Orthopantomography showed a displacement of teeth 21, 22, and 23 with an abnormal degree of opacity at the dental roots. The CT scan of the nose and sinuses revealed a tumorous lesion of expanding bony density increasing in volume at the outer wall of the left maxillary sinus, of regular shape that contained microscopic calcifications, extending into the ipsilateral orbital floor and pushing the surrounding soft tissues forward without invading them. The histopathological examination of the tumor confirmed the diagnosis of ossifying fibroma. DISCUSSION: Ossifying fibroma or fibrous osteoma is a rare and benign lesion developing insidiously with a polymorphous aspect. Of unknown etiology, most frequently located in the mandible, it is differentiated from other types of fibroma in its clinical, radiological, and histological aspects. However, only examination of the gross specimen can provide the final diagnosis. Treatment requires surgery. CONCLUSION: Surgical treatment entailed the complete macroscopic enucleoresection. Recovery has been favorable at 2 years of follow-up.


Assuntos
Fibroma Ossificante , Neoplasias do Seio Maxilar , Adulto , Fibroma Ossificante/diagnóstico , Fibroma Ossificante/cirurgia , Hospitais de Ensino , Humanos , Masculino , Neoplasias do Seio Maxilar/diagnóstico , Neoplasias do Seio Maxilar/cirurgia , Togo
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