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1.
Epilepsy Behav ; 152: 109666, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38382188

RESUMEN

PURPOSE: Although functional seizures can start at any age, little is known about the individuals for whom onset occurs after the age of 40. It has been proposed that health-related traumatic events are more relevant causal factors for people with 'later-onset functional seizures' than for those whose functional seizures begin earlier in life, however, the illness representations of people with later-onset functional seizures have not yet been investigated. This study aimed to understand the experiences and illness representations of people with later-onset functional seizures. METHODS: This was a mixed-methods study. People with later-onset functional seizures were recruited via a neurologist's caseload and online membership-led organisations. Semi-structured interview transcripts were analysed using Template Analysis according to the Common-Sense Model (CSM). Self-report measures of demographic and clinical details were collected to characterise the sample and verify themes. RESULTS: Eight people with later-onset functional seizures participated in the study. Illness representations relating to all domains of the CSM as well as an additional theme of 'Triggers' were identified. Functional seizures were characterised as a mysterious brain disorder analogous to a computer malfunction and involving involuntary movements associated with alterations in consciousness. Perceptions of duration were indefinite, and triggers were unknown or at the extremes of autonomic arousal. Half of the sample identified health-related events/trauma as causal. Opinions were divided on 'cumulative life stress' as a causal factor. Most perceived themselves to have limited or no control but having 'control' over seizures was conceptualised as different to reducing their likelihood, frequency, or impact. Later-onset functional seizures were viewed as being more detrimental for caring and financial responsibilities but to have advantages for acceptance. CONCLUSIONS: This is the first study to assess the illness representations of people with later-onset functional seizures. Many themes were similar to those identified in samples including people with earlier-onset functional seizures. Health-related trauma or events were the most strongly endorsed perceived causal factor, but with the exception of 'consequences', all representations were characterised by uncertainty. Clinicians should hold in mind the interaction between life stage and the consequences of later-onset functional seizures.


Asunto(s)
Encefalopatías , Convulsiones , Humanos , Actitud
2.
Nutr J ; 23(1): 18, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38331867

RESUMEN

BACKGROUND: Improving dietary habits is a first-line recommendation for patients with cardiovascular disease (CVD). It is unclear which dietary pattern most effectively lowers cardiovascular risk factors and what the short- and long-term effects are. Therefore, this network meta-analysis compared the effects of popular dietary patterns on cardiovascular risk factors in patients with established CVD. METHODS: A systematic search of PubMed, Embase, the Cochrane library, SCOPUS and Web of Science was conducted up to 1 April 2023. Randomized controlled trials (RCTs) comparing the effect of popular dietary patterns (Mediterranean, moderate carbohydrate, low glycemic index, low-fat and minimal dietary intervention) on cardiovascular risk factors (body weight, systolic blood pressure, lipids) in CVD populations were selected. A random-effects network meta-analysis was performed. RESULTS: Seventeen RCTs comprising 6,331 participants were included. The moderate carbohydrate diet had the most beneficial effect on body weight (-4.6 kg, 95%CrI -25.1; 15.8) and systolic blood pressure (-7.0 mmHg 95%CrI -16.8; 2.7) compared to minimal intervention. None of the included dietary patterns had a favorable effect on low-density lipoprotein cholesterol. After 12 months, the effects were attenuated compared to those at < 6 months. CONCLUSIONS: In this network meta-analysis of 17 randomized trials, potentially clinically relevant effects of dietary interventions on CV risk factors were observed, but there was considerable uncertainty due to study heterogeneity, low adherence, or actual diminished effects in the medically treated CVD population. It was not possible to select optimal dietary patterns for secondary CVD prevention. Given recent clinical trials demonstrating the potential of dietary patterns to significantly reduce cardiovascular event risk, it is likely that these effects are effectuated through alternative physiological pathways.


Asunto(s)
Enfermedades Cardiovasculares , Patrones Dietéticos , Factores de Riesgo de Enfermedad Cardiaca , Metaanálisis en Red , Prevención Secundaria , Humanos , Presión Sanguínea , Enfermedades Cardiovasculares/prevención & control , Ensayos Clínicos Controlados Aleatorios como Asunto , Prevención Secundaria/métodos
3.
J Magn Reson Imaging ; 55(3): 698-719, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33314349

RESUMEN

Arterial spin labeling (ASL) is a powerful noncontrast magnetic resonance imaging (MRI) technique that enables quantitative evaluation of brain perfusion. To optimize the clinical and research utilization of ASL, radiologists and physicists must understand the technical considerations and age-related variations in normal and disease states. We discuss advanced applications of ASL across the lifespan, with example cases from children and adults covering a wide variety of pathologies. Through literature review and illustrated clinical cases, we highlight the subtleties as well as pitfalls of ASL interpretation. First, we review basic physical principles, techniques, and artifacts. This is followed by a discussion of normal perfusion variants based on age and physiology. The three major categories of perfusion abnormalities-hypoperfusion, hyperperfusion, and mixed patterns-are covered with an emphasis on clinical interpretation and relationship to the disease process. Major etiologies of hypoperfusion include large artery, small artery, and venous disease; other vascular conditions; global hypoxic-ischemic injury; and neurodegeneration. Hyperperfusion is characteristic of vascular malformations and tumors. Mixed perfusion patterns can be seen with epilepsy, migraine, trauma, infection/inflammation, and toxic-metabolic encephalopathy. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY STAGE: 3.


Asunto(s)
Encefalopatías , Circulación Cerebrovascular , Adulto , Arterias , Encefalopatías/diagnóstico por imagen , Circulación Cerebrovascular/fisiología , Niño , Humanos , Angiografía por Resonancia Magnética/métodos , Imagen por Resonancia Magnética/métodos , Marcadores de Spin
4.
J Acoust Soc Am ; 151(1): 56, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35105007

RESUMEN

This paper describes the aeroacoustics experiments conducted with supersonic jets, exhausting from rectangular nozzles with an aspect ratio of 2, to examine the jet noise reduction by two different methods. The first method involves the use of fluid inserts, which are produced by distributed air blowing into the diverging section of a convergent-divergent exhaust nozzle. The second method involves the integration of fluid shields in dual flow rectangular jets. In the dual flow nozzle, a single shield below the exit is augmented with fluid shields extending on both sides of the rectangular jet. The purpose of the extended bypass flow is to reduce the noise radiated to the sides of a jet aircraft. In addition to the nozzles with the two noise reduction configurations, acoustic measurements are performed with a single flow rectangular jet, referred to as the baseline. In all cases, the jets are operated as overexpanded, shock-containing jets. In some cases, the jets are operated with the core flow mixtures of helium and air to simulate high temperature jets. The far-field noise measurements are performed on an arc with the microphones approximately 70 equivalent nozzle diameters from the nozzle exit. For the purposes of assessing the noise reduction capability of the dual stream jet, comparisons are made with a baseline rectangular jet on an equal thrust per unit exit area basis. The nondimensional acoustic spectra and overall sound pressure level directivities are shown and compared.

5.
Breast Cancer Res Treat ; 187(3): 635-645, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33983492

RESUMEN

BACKGROUND: Pre-treatment tumour-associated lymphocytes (TILs) and stromal lymphocytes (SLs) are independent predictive markers of future pathological complete response (pCR) in HER2-positive breast cancer. Whilst studies have correlated baseline lymphocyte levels with subsequent pCR, few have studied the impact of neoadjuvant therapy on the immune environment. METHODS: We performed TIL analysis and T-cell analysis by IHC on the pretreatment and 'On-treatment' samples from patients recruited on the Phase-II TCHL (NCT01485926) clinical trial. Data were analysed using the Wilcoxon signed-rank test and the Spearman rank correlation. RESULTS: In our sample cohort (n = 66), patients who achieved a pCR at surgery, post-chemotherapy, had significantly higher counts of TILs (p = 0.05) but not SLs (p = 0.08) in their pre-treatment tumour samples. Patients who achieved a subsequent pCR after completing neo-adjuvant chemotherapy had significantly higher SLs (p = 9.09 × 10-3) but not TILs (p = 0.1) in their 'On-treatment' tumour biopsies. In a small cohort of samples (n = 16), infiltrating lymphocyte counts increased after 1 cycle of neo-adjuvant chemotherapy only in those tumours of patients who did not achieve a subsequent pCR. Finally, reduced CD3 + (p = 0.04, rho = 0.60) and CD4 + (p = 0.01, rho = 0.72) T-cell counts in 'On-treatment' biopsies were associated with decreased residual tumour content post-1 cycle of treatment; the latter being significantly associated with increased likelihood of subsequent pCR (p < 0.01). CONCLUSIONS: The immune system may be 'primed' prior to neoadjuvant treatment in those patients who subsequently achieve a pCR. In those patients who achieve a pCR, their immune response may return to baseline after only 1 cycle of treatment. However, in those who did not achieve a pCR, neo-adjuvant treatment may stimulate lymphocyte influx into the tumour.


Asunto(s)
Neoplasias de la Mama , Terapia Neoadyuvante , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Femenino , Humanos , Linfocitos , Linfocitos Infiltrantes de Tumor , Pronóstico , Receptor ErbB-2/genética
6.
Br J Dermatol ; 181(5): 983-991, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31049932

RESUMEN

BACKGROUND: All organ transplant populations are predisposed to increased rates of keratinocyte carcinoma (KC). Since this increased risk was first appreciated, immunosuppressive regimens have changed and organ transplant recipients (OTRs) have been aggressively screened for KC. There is a perception that these measures have impacted on KC incidence but there is a paucity of population-based studies on post-transplant rates of basal cell carcinoma (BCC). OBJECTIVES: To identify trends in incidence rates for KC following solid organ transplantation over the past two decades. METHODS: This nationwide, population-based study included all solid OTRs transplanted between 1994 and 2014. Patient data were matched to national cancer registry data to determine the standardized incidence ratio (SIR) of KC in solid OTRs compared with the general population. RESULTS: In total 3580 solid OTRs were included. The total follow-up time was 28 407 person-years (median follow-up 7·11 years). The overall SIRs for squamous cell carcinoma (SCC) and BCC were 19·7 and 7·0, respectively. Our study documents a progressive fall in the SIRs for SCC and BCC from peak SIRs (95% confidence intervals) in 1994-1996 of 26·4 (21·5-32·4) and 9·1 (7·4-11·3) to 6·3 (2·3-16·7) and 3·2 (1·4-7·1) in 2012-2014, respectively. The ratio of SCC to BCC has remained at 3 to 1 over the last two decades. CONCLUSIONS: Our study is the first to demonstrate a significant reduction over the past two decades in the incidences of both SCC and BCC following solid organ transplantation. The SCC-to-BCC ratio was maintained, demonstrating that both are reducing equally. This trend coincided with temporal changes in immunosuppressive protocols and the introduction of skin cancer prevention programmes. What's already known about this topic? Prior studies have shown that the risk of cutaneous squamous cell carcinoma (SCC) has declined over recent decades following solid organ transplantation. It is not known whether the risk of basal cell carcinoma (BCC) has reduced in line with this. What does this study add? Our study documents a progressive fall in the risk of SCC and BCC following solid organ transplantation over the last two decades. The SCC-to-BCC ratio was maintained, demonstrating that both are reducing equally. The trends observed in our study coincided with temporal changes in immunosuppressive protocols and the introduction of cancer prevention programmes, suggesting that these factors have positively impacted on the risk of keratinocyte carcinoma in this cohort.


Asunto(s)
Carcinoma Basocelular/epidemiología , Carcinoma de Células Escamosas/epidemiología , Trasplante de Órganos/efectos adversos , Neoplasias Cutáneas/epidemiología , Receptores de Trasplantes/estadística & datos numéricos , Adolescente , Adulto , Anciano , Carcinoma Basocelular/etiología , Carcinoma Basocelular/prevención & control , Carcinoma de Células Escamosas/etiología , Carcinoma de Células Escamosas/prevención & control , Niño , Preescolar , Femenino , Estudios de Seguimiento , Rechazo de Injerto/inmunología , Rechazo de Injerto/prevención & control , Humanos , Terapia de Inmunosupresión/efectos adversos , Terapia de Inmunosupresión/métodos , Incidencia , Lactante , Irlanda/epidemiología , Masculino , Persona de Mediana Edad , Sistema de Registros/estadística & datos numéricos , Neoplasias Cutáneas/etiología , Neoplasias Cutáneas/prevención & control , Adulto Joven
8.
Ann Neurol ; 81(2): 298-309, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28120349

RESUMEN

OBJECTIVE: A novel autoimmune central nervous system (CNS) disorder with glial fibrillary acidic protein (GFAP)-IgG as biomarker was recently characterized. Here, 102 patients with GFAP-IgG positivity are described. METHODS: The 102 included patients had: (1) serum, cerebrospinal fluid (CSF), or both that yielded a characteristic astrocytic pattern of mouse tissue immunostaining; (2) confirmation of IgG reactive with specific GFAP isoforms (α, ɛ, or κ) by cell-based assays; and (3) clinical data available. Control specimens (n = 865) were evaluated by tissue (n = 542) and cell-based (n = 323) assays. RESULTS: Median symptom onset age was 44 years (range = 8-103), and 54% were women. The predominant phenotype (83 patients; 81%) was inflammation of meninges, brain, spinal cord, or all 3 (meningoencephalomyelitis). Among patients, highest specificity for those phenotypes was observed for CSF testing (94%), and highest sensitivity was for the GFAPα isoform (100%). Rare GFAP-IgG positivity was encountered in serum controls by tissue-based assay (0.5%) or cell-based assay (1.5%), and in CSF controls by cell-based assay (0.9%). Among patients, striking perivascular radial enhancement was found on brain magnetic resonance imaging in 53%. Although cases frequently mimicked vasculitis, angiography was uniformly negative, and spinal imaging frequently demonstrated longitudinally extensive myelitic lesions. Diverse neoplasms encountered were found prospectively in 22%. Ovarian teratoma was most common and was predicted best when both N-methyl-D-aspartate receptor-IgG and aquaporin-4-IgG coexisted (71%). Six patients with prolonged follow-up had brisk corticosteroid response, but required additional immunosuppression to overcome steroid dependency. INTERPRETATION: GFAPα-IgG, when detected in CSF, is highly specific for an immunotherapy-responsive autoimmune CNS disorder, sometimes with paraneoplastic cause. Ann Neurol 2017;81:298-309.


Asunto(s)
Astrocitos/patología , Autoanticuerpos/líquido cefalorraquídeo , Enfermedades Autoinmunes del Sistema Nervioso/líquido cefalorraquídeo , Proteína Ácida Fibrilar de la Glía/inmunología , Síndromes Paraneoplásicos del Sistema Nervioso/líquido cefalorraquídeo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Biomarcadores/líquido cefalorraquídeo , Niño , Femenino , Humanos , Inmunoglobulina G , Imagen por Resonancia Magnética , Masculino , Ratones , Persona de Mediana Edad , Adulto Joven
9.
J Anim Physiol Anim Nutr (Berl) ; 102(2): e798-e805, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29134690

RESUMEN

According to a previous meta-analysis, adult dogs do not notably increase calcium absorption from the gastrointestinal tract when calcium intake is decreased. This results in a negative calcium balance even with a moderate calcium reduction. In this study we wanted to verify (i) whether a negative calcium balance occurs at a calcium intake equivalent to NRC (2006) (Nutrient requirements of dogs and cats, 2006, The National Academies Press, Washington, DC) minimal requirements, and if so (ii) whether the negative calcium balance will persist for up to 6 months on a low-calcium diet. After a pre-feeding period of at least 18 weeks with calcium intake slightly exceeding maintenance requirements (200 mg/kg body weight0.75 ), 12 dogs (6 Beagles, 6 Foxhound crossbreds) were fed a low-calcium diet for 28 weeks. One dog was removed from the trial for reasons unrelated to the study at week 23. Calcium intake amounted to 60 mg/kg body weight0.75 corresponding to the minimal requirement for maintenance in dogs (NRC, 2006 (Nutrient requirements of dogs and cats, 2006, The National Academies Press, Washington, DC)). Digestion trials were carried out at week 7, 14, 21 and 28 of the low calcium feeding period. At these time points, and at week 18 of the pre-trial, blood samples were taken and analysed for calcium, ionised calcium, phosphorus, parathyroid hormone, vitamin D, serum crosslaps and bone alkaline phosphatase. Apparent calcium digestibility was negative throughout the study, suggesting a negative calcium balance. There was no systematic decrease in faecal calcium excretion. Serum calcium, ionised calcium and phosphorus remained within the reference range. Serum crosslaps increased continuously from baseline to week 28 of trial, with averages increasing from 0.102 ng/ml to 0.279 ng/ml, suggesting osteoclastic activity, indicative of calcium mobilisation from the skeleton. The study supports the theory of a lack of adaptation of intestinal calcium absorption from diets with relatively low calcium content in dogs. This agrees with clinical findings in dogs eating low-calcium diet.


Asunto(s)
Calcio de la Dieta/administración & dosificación , Calcio/química , Calcio/metabolismo , Heces/química , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Perros , Femenino
10.
Neuroimage ; 130: 273-292, 2016 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-26827811

RESUMEN

Understanding the electrophysiological basis of resting state networks (RSNs) in the human brain is a critical step towards elucidating how inter-areal connectivity supports healthy brain function. In recent years, the relationship between RSNs (typically measured using haemodynamic signals) and electrophysiology has been explored using functional Magnetic Resonance Imaging (fMRI) and magnetoencephalography (MEG). Significant progress has been made, with similar spatial structure observable in both modalities. However, there is a pressing need to understand this relationship beyond simple visual similarity of RSN patterns. Here, we introduce a mathematical model to predict fMRI-based RSNs using MEG. Our unique model, based upon a multivariate Taylor series, incorporates both phase and amplitude based MEG connectivity metrics, as well as linear and non-linear interactions within and between neural oscillations measured in multiple frequency bands. We show that including non-linear interactions, multiple frequency bands and cross-frequency terms significantly improves fMRI network prediction. This shows that fMRI connectivity is not only the result of direct electrophysiological connections, but is also driven by the overlap of connectivity profiles between separate regions. Our results indicate that a complete understanding of the electrophysiological basis of RSNs goes beyond simple frequency-specific analysis, and further exploration of non-linear and cross-frequency interactions will shed new light on distributed network connectivity, and its perturbation in pathology.


Asunto(s)
Mapeo Encefálico/métodos , Encéfalo/fisiología , Modelos Neurológicos , Modelos Teóricos , Red Nerviosa/fisiología , Hemodinámica , Humanos , Imagen por Resonancia Magnética , Magnetoencefalografía
12.
Tijdschr Gerontol Geriatr ; 47(6): 234-248, 2016 Dec.
Artículo en Holandés | MEDLINE | ID: mdl-27882453

RESUMEN

BACKGROUND: Multimorbidity, functional impairment and frailty among community-dwelling older people are causing increasing complexity in primary care. A proactive integrated primary care approach is therefore essential. Between October 2014-2015, an evidence-based proactive care program for frail older people was implemented in the region Noord-West Veluwe en Zeewolde, the Netherlands. This study evaluated the feasibility of the implementation, having a strong focus on the collaboration between the medical and social domain. METHODS: Using a mixed-methods design we evaluated several process indicators. Data were obtained from electronic routine medical record data within primary care, questionnaires, and interviews with older adults. The questionnaires provided information regarding the expectations and experiences towards the program and were sent to health care professionals at baseline and six months follow-up. Stakeholders from various domains were asked to fill in the questionnaire at baseline and twelve months follow-up. Interviews were conducted to explore the experiences of older adults with the program. Regional work groups were set up in each municipality to enhance the interdisciplinary and domain transcending collaboration. RESULTS: The proactive primary care program was implemented in 42 general practices who provided care to 7904 older adults aged 75 years or older. A total of 101 health care professionals and 44 stakeholders filled in the questionnaires. The need for better structure and interdisciplinary cooperation seemed widespread among the participants. The implementation resulted in a positive significant change in the demand for a better regional healthcare-framework (34% p ≤ .001) among health care professionals, and the needs for transparency regarding the possibilities for referral improved (27% , p = .009). Half of the participants reported that the regional collaboration has been improved after the implementation. Health care professionals and stakeholders gained increased attention and awareness of frail elderly in their area compared to before the implementation. Older people and their caregivers were positive about the proactive approach. The nurses reported that the screenings questionnaire was too lengthy and therefore time consuming. CONCLUSIONS: The implementation of the proactive primary care approach in daily practice was feasible. A strong interdisciplinary collaboration was realized. The program was easily adapted to the local context.


Asunto(s)
Anciano Frágil , Servicios de Salud para Ancianos/organización & administración , Atención Primaria de Salud/organización & administración , Anciano de 80 o más Años , Atención a la Salud , Medicina Basada en la Evidencia , Femenino , Humanos , Masculino , Países Bajos , Encuestas y Cuestionarios
13.
Eur J Neurosci ; 42(9): 2633-43, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26370007

RESUMEN

N-Methyl-D-aspartate glutamate receptors (NMDARs) contribute to neural development, plasticity and survival, but they are also linked with neurodegeneration. NMDARs at synapses are activated by coincident glutamate release and depolarization. NMDARs distal to synapses can sometimes be recruited by 'spill-over' of glutamate during high-frequency synaptic stimulation or when glutamate uptake is compromised, and this influences the shape of NMDAR-mediated postsynaptic responses. In substantia nigra dopamine neurons, activation of NMDARs beyond the synapse during different frequencies of presynaptic stimulation has not been explored, even though excitatory afferents from the subthalamic nucleus show a range of firing frequencies, and these frequencies change in human and experimental Parkinson's disease. This study reports that high-frequency stimulation (80 Hz/200 ms) evoked NMDAR-excitatory postsynaptic currents (EPSCs) that were larger and longer lasting than those evoked by single stimuli at low frequency (0.1 Hz). MK-801, which irreversibly blocked NMDAR-EPSCs activated during 0.1-Hz stimulation, left a proportion of NMDAR-EPSCs that could be activated by 80-Hz stimulation and that may represent activity of NMDARs distal to synapses. TBOA, which blocks glutamate transporters, significantly increased NMDAR-EPSCs in response to 80-Hz stimulation, particularly when metabotropic glutamate receptors (mGluRs) were also blocked, indicating that recruitment of NMDARs distal to synapses is regulated by glutamate transporters and mGluRs. These regulatory mechanisms may be essential in the substantia nigra for restricting glutamate diffusion from synaptic sites and keeping NMDAR-EPSCs in dopamine neurons relatively small and fast. Failure of glutamate transporters may contribute to the declining health of dopamine neurons during pathological conditions.


Asunto(s)
Neuronas Dopaminérgicas/fisiología , Potenciales Postsinápticos Excitadores , Ácido Glutámico/fisiología , Receptores de N-Metil-D-Aspartato/fisiología , Sustancia Negra/fisiología , Sinapsis/fisiología , Aminoácidos/farmacología , Animales , Ácido Aspártico/farmacología , Maleato de Dizocilpina/farmacología , Neuronas Dopaminérgicas/efectos de los fármacos , Estimulación Eléctrica , Antagonistas de Aminoácidos Excitadores/farmacología , Potenciales Postsinápticos Excitadores/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Sinapsis/efectos de los fármacos , Xantenos/farmacología
14.
Eur J Clin Microbiol Infect Dis ; 34(11): 2275-85, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26363637

RESUMEN

Although long-term azithromycin decreases exacerbation frequency in bronchiectasis, increased macrolide resistance is concerning. We investigated macrolide resistance determinants in a secondary analysis of a multicenter randomized controlled trial. Indigenous Australian children living in remote regions and urban New Zealand Maori and Pacific Islander children with bronchiectasis were randomized to weekly azithromycin (30 mg/kg) or placebo for up to 24 months and followed post-intervention for up to 12 months. Nurses administered and recorded medications given and collected nasopharyngeal swabs 3-6 monthly for culture and antimicrobial susceptibility testing. Nasopharyngeal carriage of Haemophilus influenzae and Moraxella catarrhalis was significantly lower in azithromycin compared to placebo groups, while macrolide-resistant Streptococcus pneumoniae and Staphylococcus aureus carriage was significantly higher. Australian children, compared to New Zealand children, had higher carriage overall, significantly higher carriage of macrolide-resistant bacteria at baseline (16/38 versus 2/40 children) and during the intervention (69/152 versus 22/239 swabs), and lower mean adherence to study medication (63 % versus 92 %). Adherence ≥70 % (versus <70 %) in the Australian azithromycin group was associated with lower carriage of any pathogen [odds ratio (OR) 0.19, 95 % confidence interval (CI) 0.07-0.53] and fewer macrolide-resistant pathogens (OR 0.34, 95 % CI 0.14-0.81). Post-intervention (median 6 months), macrolide resistance in S. pneumoniae declined significantly in the azithromycin group, from 79 % (11/14) to 7 % (1/14) of positive swabs, but S. aureus strains remained 100 % macrolide resistant. Azithromycin treatment, the Australian remote setting, and adherence <70 % were significant independent determinants of macrolide resistance in children with bronchiectasis. Adherence to treatment may limit macrolide resistance by suppressing carriage.


Asunto(s)
Antibacterianos/farmacología , Azitromicina/uso terapéutico , Bacterias/efectos de los fármacos , Infecciones Bacterianas/microbiología , Farmacorresistencia Bacteriana , Macrólidos/farmacología , Nasofaringe/microbiología , Antibacterianos/uso terapéutico , Australia , Bacterias/aislamiento & purificación , Infecciones Bacterianas/tratamiento farmacológico , Bronquiectasia/complicaciones , Portador Sano/microbiología , Niño , Preescolar , Femenino , Humanos , Lactante , Macrólidos/uso terapéutico , Masculino , Nueva Zelanda , Islas del Pacífico , Placebos/administración & dosificación , Grupos de Población
15.
J Anim Physiol Anim Nutr (Berl) ; 99(5): 801-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25808498

RESUMEN

A meta-analysis was conducted to understand quantitative aspects of calcium (Ca) and phosphorus (P) absorption in adult dogs and cats. 34 studies in dogs and 14 studies in cats met the criteria for inclusion in the meta-analysis. Intake and faecal excretion values of Ca and P were subjected to a modified Lucas test and subsequent regression analyses. According to the current scientific consensus, Ca true digestibility (absorption) should increase at low Ca intake and decrease at high Ca intake. If true, this should result in a nonlinear relationship between the percentage of Ca excreted and dietary Ca intake. The present meta-analysis showed a highly significant linear relationship (p < 0.0001) between Ca intake and Ca excretion suggesting a lack of systematic quantitative adaptation in true Ca digestibility. This finding suggests either that the time period covered by standard digestion trials is too short to induce adaptation mechanisms or that dogs and cats at maintenance will not efficiently alter quantitative Ca absorption percentage according to the amount ingested. If the latter is true, a dietary Ca supply differing greatly from the recommended dietary intake might impair the health of cats and dogs when fed long term. The data plots for P intake and faecal excretion were less uniform suggesting other factors not just dietary intake influence faecal P excretion. In adult cats, the dietary Ca:P ratio strongly influenced the true digestibility of P, whereas this effect was less marked in adult dogs. Faecal P excretion was significantly correlated to faecal Ca excretion in both species (p < 0.0001), and surprisingly, the level of P intake did not appear to be an important determinant of true digestibility of P.


Asunto(s)
Calcio/farmacocinética , Gatos/fisiología , Perros/fisiología , Envejecimiento , Alimentación Animal/análisis , Animales , Minerales/farmacocinética , Fósforo/farmacocinética
16.
Am J Transplant ; 14(12): 2765-76, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25395336

RESUMEN

Invasive fungal infections (IFIs) cause significant morbidity and mortality in liver transplant recipients, but the need and best agent for prophylaxis is uncertain. A comprehensive literature search was performed to identify randomized controlled trials comparing regimens for antifungal prophylaxis in liver transplant recipients. Direct comparisons were made between treatments using random-effects meta-analysis and a Bayesian network meta-analysis was performed for the primary end point of proven IFI. Fourteen studies met inclusion criteria, reporting comparisons of fluconazole, liposomal amphotericin B (L-AmB), itraconazole, micafungin and placebo. Overall, antifungal prophylaxis reduced the rate of proven IFI (odds ratio [OR] 0.37, confidence interval [CI] 0.19-0.72, p = 0.003), suspected or proven IFI (OR 0.40, CI 0.25-0.66, p = 0.0003) and mortality due to IFI (OR 0.32, CI 0.10-0.83, p = 0.02) when compared to placebo. All-cause mortality was not significantly affected. There was no difference in risk of adverse events requiring cessation of prophylaxis (OR 1.11, 95% CI 0.48-2.55, p = 0.81). In the network meta-analysis an equivalent reduction in the rate of IFI was seen with fluconazole (OR 0.21, CI 0.06-0.57) and L-AmB (OR 0.21, CI 0.05-0.71) compared with placebo. Routine prophylaxis with fluconazole or L-AmB reduces the incidence of IFI following liver transplantation, and the available evidence suggests that the two are equivalent in efficacy.


Asunto(s)
Profilaxis Antibiótica , Antifúngicos/uso terapéutico , Rechazo de Injerto/prevención & control , Hepatopatías/cirugía , Trasplante de Hígado/efectos adversos , Micosis/prevención & control , Complicaciones Posoperatorias , Rechazo de Injerto/etiología , Humanos , Micosis/microbiología
18.
Neuroendocrinology ; 100(4): 317-33, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25378037

RESUMEN

BACKGROUND: The neuropeptide RFamide-related peptide-3 (RFRP-3; mammalian ortholog to gonadotropin-inhibiting hormone) can inhibit luteinizing hormone (LH) release and increases feeding, but the regulation and development of RFRP-3 neurons remains poorly characterized, especially in mice. METHODS AND RESULTS: We first confirmed that peripheral injections of murine RFRP-3 peptide could markedly suppress LH secretion in adult mice, as in other species. Second, given RFRP-3's reported orexigenic properties, we performed double-label in situ hybridization for metabolic genes in Rfrp neurons of mice. While Rfrp neurons did not readily coexpress neuropeptide Y, thyrotropin-releasing hormone, or MC4R, a small subset of Rfrp neurons did express the leptin receptor in both sexes. Surprisingly, we identified no changes in Rfrp expression or neuronal activation in adult mice after acute fasting. However, we determined that Rfrp mRNA levels in the dorsal-medial nucleus were significantly reduced in adult obese (Ob) mice of both sexes. Given the lower Rfrp levels observed in adult Ob mice, we asked whether leptin might also regulate RFRP-3 neuron development. Rfrp gene expression changed markedly over juvenile development, correlating with the timing of the juvenile 'leptin surge' known to govern hypothalamic feeding circuit development. However, the dramatic developmental changes in juvenile Rfrp expression did not appear to be leptin driven, as the pattern and timing of Rfrp neuron development were unaltered in Ob juveniles. CONCLUSION: Leptin status modulates RFRP-3 expression in adulthood, but is not required for normal development of the RFRP-3 system. Leptin's regulation of adult RFRP-3 neurons likely occurs primarily via indirect signaling, and may be secondary to obesity, as only a small subset of RFRP-3 neurons express the long form of the leptin receptor (LepRb).


Asunto(s)
Leptina/metabolismo , Neuronas/metabolismo , Neuropéptidos/metabolismo , Receptores de Leptina/metabolismo , Factores de Edad , Animales , Femenino , Privación de Alimentos , Hormona Luteinizante/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Neuronas/efectos de los fármacos , Neuropéptidos/farmacología
19.
Rural Remote Health ; 14(2): 2759, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24924831

RESUMEN

INTRODUCTION: Australian Indigenous children suffer a high burden of diarrhoeal disease. Nitazoxanide is an antimicrobial that has been shown to be effective against a broad range of enteropathogens. To date, its use has not been reported in the tropical Top End (northernmost part) of the Northern Territory, Australia. The objective was to describe the use of nitazoxanide at the Royal Darwin Hospital, Northern Territory, and to assess any association with the time to resolution of diarrhoea. METHODS: Eligible children (≤13 years) were identified from dispensary records as having been prescribed nitazoxanide during the audit period, 1 July 2007 to 31 March 2012. Patient demographics, symptoms, diarrheal aetiology, treatment details and clinical outcomes were obtained by chart review. RESULTS: Twenty-eight children were treated with nitazoxanide, mostly for Cryptosporidium infection associated with prolonged diarrhoea. Dehydration was evident in 27 (96%) children on admission, and 11 (41%) were underweight. Diarrhoeal duration prior to treatment was 11.5 days (6.5 days pre- and 5 days post-admission). For children ≥12 months, nitazoxanide was prescribed according to guidelines stipulated by the Centers for Disease Control and Prevention (CDC). Resolution of diarrhoea occurred a median of 2.4 days (IQR: 1.4-7.3) after starting treatment. An increase in weight for length at discharge was found for all children. CONCLUSIONS: Prompt resolution of diarrhoea without adverse outcomes suggests nitazoxanide may be an effective treatment for Cryptosporidium infection in this setting. Its role in the treatment of other causes of infectious diarrhoea needs further investigation. Randomised trials will further direct its use and determine optimal dosing regimens.


Asunto(s)
Antiinfecciosos/uso terapéutico , Disentería/tratamiento farmacológico , Tiazoles/uso terapéutico , Adolescente , Niño , Deshidratación/epidemiología , Disentería/epidemiología , Disentería/etnología , Femenino , Humanos , Masculino , Nativos de Hawái y Otras Islas del Pacífico , Nitrocompuestos , Northern Territory/epidemiología , Factores Socioeconómicos , Delgadez/epidemiología
20.
Opt Express ; 21(25): 30460-73, 2013 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-24514623

RESUMEN

Ghost imaging and ghost diffraction can be realized by using the spatial correlations between signal and idler photons produced by spontaneous parametric down-conversion. If an object is placed in the signal (idler) path, the spatial correlations between the transmitted photons as measured by a single, non-imaging, "bucket" detector and a scanning detector placed in the idler (signal) path can reveal either the image or diffraction pattern of the object, whereas neither detector signal on its own can. The details of the bucket detector, such as its collection area and numerical aperture, set the number of transverse modes supported by the system. For ghost imaging these details are less important, affecting mostly the sampling time required to produce the image. For ghost diffraction, however, the bucket detector must be filtered to a single, spatially coherent mode. We examine this difference in behavour by using either a multi-mode or single-mode fibre to define the detection aperture. Furthermore, instead of a scanning detector we use a heralded camera so that the image or diffraction pattern produced can be measured across the full field of view. The importance of a single mode detection in the observation of ghost diffraction is equivalent to the need within a classical diffraction experiment to illuminate the aperture with a spatially coherent mode.

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