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1.
Clin Radiol ; 78(6): 444-450, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37029001

RESUMO

AIM: To evaluate the effectiveness of an ultrafast breast magnetic resonance imaging (MRI) protocol in differentiating benign and malignant breast lesions. MATERIALS AND METHODS: Fifty-four patients with Breast Imaging Reporting and Data System (BI-RADS) 4 or 5 lesions were recruited between July 2020 to May 2021. A standard breast MRI was performed with the inclusion of the ultrafast protocol between the unenhanced sequence and the first contrast-enhanced sequence. Three radiologists performed image interpretation in consensus. Ultrafast kinetic parameters analysed included the maximum slope (MS), time to enhancement (TTE), and arteriovenous index (AVI). These parameters were compared using receiver operating characteristics with p-values of <0.05 considered to indicate statistical significance. RESULTS: Eighty-three histopathological proven lesions from 54 patients (mean age 53.87 years, SD 12.34, range 26-78 years) were analysed. Forty-one per cent (n=34) were benign and 59% (n=49) were malignant. All malignant and 38.2% (n=13) benign lesions were visualised on the ultrafast protocol. Of the malignant lesions, 77.6% (n=53) were invasive ductal carcinoma (IDC) and 18.4% (n=9) were ductal carcinoma in situ (DCIS). The MS for malignant lesions (13.27%/s) were significantly larger than for benign (5.45%/s; p<0.0001). No significant differences were seen for TTE and AVI. The area under the ROC curve (AUC) for the MS, TTE, and AVI were 0.836, 0.647, and 0.684, respectively. Different types of invasive carcinoma had similar MS and TTE. The MS of high-grade DCIS was also similar to that of IDC. Lower MS values were observed for low-grade (5.3%/s) compared to high-grade DCIS (14.8%/s) but the results were not significant statistically. CONCLUSION: The ultrafast protocol showed potential to discriminate between malignant and benign breast lesions with high accuracy using MS.


Assuntos
Carcinoma de Mama in situ , Neoplasias da Mama , Carcinoma Intraductal não Infiltrante , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Feminino , Meios de Contraste , Diagnóstico Diferencial , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos
4.
Hum Reprod ; 36(7): 1907-1921, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34052851

RESUMO

STUDY QUESTION: What is the transcriptome signature associated with poor performance of rescue IVM (rIVM) oocytes and how can we rejuvenate them? SUMMARY ANSWER: The GATA-1/CREB1/WNT signalling axis was repressed in rIVM oocytes, particularly those of poor quality; restoration of this axis may produce more usable rIVM oocytes. WHAT IS KNOWN ALREADY: rIVM aims to produce mature oocytes (MII) for IVF through IVM of immature oocytes collected from stimulated ovaries. It is not popular due to limited success rate in infertility treatment. Genetic aberrations, cellular stress and the absence of cumulus cell support in oocytes could account for the failure of rIVM. STUDY DESIGN, SIZE, DURATION: We applied single-cell RNA sequencing (scRNA-seq) to capture the transcriptomes of human in vivo oocytes (IVO) (n = 10) from 7 donors and rIVM oocytes (n = 10) from 10 donors. The effects of maternal age and ovarian responses on rIVM oocyte transcriptomes were also studied. In parallel, we studied the effect of gallic acid on the maturation rate of mouse oocytes cultured in IVM medium with (n = 84) and without (n = 85) gallic acid. PARTICIPANTS/MATERIALS, SETTING, METHODS: Human oocytes were collected from donors aged 28-41 years with a body mass index of <30. RNA extraction, cDNA generation, library construction and sequencing were performed in one preparation. scRNA-seq data were then processed and analysed. Selected genes in the rIVM versus IVO comparison were validated by quantitative real-time PCR. For the gallic acid study, we collected immature oocytes from 5-month-old mice and studied the effect of 10-µM gallic acid on their maturation rate. MAIN RESULTS AND THE ROLE OF CHANCE: The transcriptome profiles of rIVM/IVO oocytes showed distinctive differences. A total of 1559 differentially expressed genes (DEGs, genes with at least 2-fold change and adjusted P < 0.05) were found to be enriched in metabolic processes, biosynthesis and oxidative phosphorylation. Among these DEGs, we identified a repression of WNT/ß-catenin signalling in rIVM when compared with IVO oocytes. We found that oestradiol levels exhibited a significant age-independent correlation with the IVO mature oocyte ratio (MII ratio) for each donor. rIVM oocytes from women with a high MII ratio were found to have over-represented cellular processes such as anti-apoptosis. To further identify targets that contribute to the poor clinical outcomes of rIVM, we compared oocytes collected from young donors with a high MII ratio with oocytes from donors of advanced maternal age and lower MII ratio, and revealed that CREB1 is an important regulator. Thus, our study identified that GATA-1/CREB1/WNT signalling was repressed in both rIVM oocytes versus IVO oocytes and in rIVM oocytes of lower versus higher quality. Consequently we investigated gallic acid, as a potential antioxidant substrate in human rIVM medium, and found that it increased the mouse oocyte maturation rate by 31.1%. LARGE SCALE DATA: Raw data from this study can be accessed through GSE158539. LIMITATIONS, REASONS FOR CAUTION: In the rIVM oocytes of the high- and low-quality comparison, the number of samples was limited after data filtering with stringent selection criteria. For the oocyte stage identification, we were unable to predict the presence of oocyte spindle, so polar body extrusion was the only indicator. WIDER IMPLICATIONS OF THE FINDINGS: This study showed that GATA-1/CREB1/WNT signalling was repressed in rIVM oocytes compared with IVO oocytes and was further downregulated in low-quality rIVM oocytes, providing us the foundation of subsequent follow-up research on human oocytes and raising safety concerns about the clinical use of rescued oocytes. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the Collaborative Research Fund, Research Grants Council, C4054-16G, and Research Committee Funding (Research Sustainability of Major RGC Funding Schemes), The Chinese University of Hong Kong. The authors have no conflicts of interest to declare.


Assuntos
Oócitos , Indução da Ovulação , Animais , Células do Cúmulo , Feminino , Técnicas de Maturação in Vitro de Oócitos , Camundongos , Oogênese , Análise de Sequência de RNA
5.
Malays J Pathol ; 42(3): 461-467, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33361730

RESUMO

INTRODUCTION: Primary gastrointestinal melanomas are mucosal malignancies that arise from melanocytes in the oropharynx, rectum, and anus. Anorectal malignant melanoma (ARMM) are exceedingly rare, accounting for less than 1% of all melanomas, 0.1% of all rectal malignancies and 4% of anal malignancies. Diagnosis is frequently delayed as these lesions are often mistaken for haemorrhoids. Histological evaluation with special immunohistochemical stains is often necessary for definitive diagnosis. Due to the aggressive nature, 61% of patients with ARMM would already have lymph node involvement or distant metastases, by the time of diagnosis. Prognosis is usually poor with 5-year survival rate of <20%. We report a case of metastatic ARMM in an elderly lady who presented with symptoms and signs mimicking a haemorrhoid. CASE REPORT: A 69-year-old lady presented with one year history of intermittent rectal bleed and an anorectal mass that was initially treated as haemorrhoid. Colonoscopy showed a hyperpigmented mass in the anorectal region which was confirmed as malignant melanoma on histopathological examination. Imaging with CT and MRI demonstrated locally advanced tumour with distant metastases to the liver and lung. Patient was referred for palliative management. CONCLUSION: ARMM is a rare malignancy and often presented with non-specific clinical signs. Diagnosis is frequently delayed without high index of suspicion. MRI pelvis is the imaging of choice to assess local extent of disease. Histologic evaluation with special immunohistochemical stains is often necessary for definitive diagnosis. Prognosis is poor despite surgical and chemotherapeutic interventions.


Assuntos
Neoplasias do Ânus/patologia , Melanoma/patologia , Neoplasias Retais/patologia , Idoso , Feminino , Humanos
6.
Aust Vet J ; 98(1-2): 17-25, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31742667

RESUMO

OBJECTIVE: To determine the prevalence of positive allergen reactions in intradermal and IgE serological tests in dogs presenting to a dermatology referral centre in South Australia and the clinical efficacy of subsequent allergen-specific immunotherapy. DESIGN: Retrospective study. METHODS: Results from 108 intradermal allergy tests, 25 IgE serological assays and immunotherapy outcomes in 37 dogs were retrospectively analysed. Immunotherapy outcomes were determined as excellent, good, modest or failure using a global assessment of efficacy matrix which incorporated pruritus scores, lesion severity, medication requirements, and owner and clinician opinion. RESULTS: The most common positive reactions in intradermal allergy tests were Red clover (59%), Dermatophagoides farinae (29%), Tyrophagus putrescentiae (28%), Yellow dock (25%) and Malassezia pachydermatis (24%). In the IgE serological tests, Yorkshire fog grass (40%), Yellow dock (36%), Kentucky bluegrass (36%) and T. putrescentiae (36%) were the most commonly reported positive results. The outcome of allergen-specific immunotherapy was judged to be excellent in 20% of dogs, good in 15%, modest in 18% and a failure in 47%. CONCLUSION: As has been reported in other geographical areas, environmental mites and plant pollens frequently gave positive reactions in allergy tests in South Australia. However, the prevalence of individual allergen reactions differed between intradermal and IgE serological tests, with M. pachydermatis being identified as a common cause of hypersensitivity in intradermal tests but not in IgE serological assays. Immunotherapy was judged to be a beneficial treatment in 35% of dogs but was essentially unsuccessful in 65%.


Assuntos
Dermatite Atópica/veterinária , Doenças do Cão , Hipersensibilidade/veterinária , Alérgenos , Animais , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Imunoglobulina E , Imunoterapia/veterinária , Prevalência , Estudos Retrospectivos , Austrália do Sul
7.
J Acoust Soc Am ; 146(3): 1580, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31590498

RESUMO

The acoustical insertion loss of asymmetrical balconies on high-rise buildings was studied experimentally using a 1:3 scaled down model in the present study. Four balcony forms featured by the presence of a full-height side-wall were included. A linear loudspeaker array was adopted as the sound source. The effects of source orientation and balcony elevation angle on the insertion loss and its spectral variation were examined. The position of the full-height side-wall relative to the sound source significantly affects the balcony insertion loss. It is observed that the maximum traffic noise amplification and attenuation are both ∼6 dBA. Results also suggest that the balustrade has no effect on the insertion loss spectral variation pattern, though the insertion loss magnitude could be much reduced without it in the presence of a short side-wall. This short side-wall determines the insertion loss spectral variation pattern. Significant sound amplification is found at frequencies of the odd order transverse modes, the longitudinal modes, and their coupled modes regardless of balcony form and elevation angle. It is also found that the major acoustic mode interactions are basically independent of source orientation for balconies without the short side-wall.

8.
Med J Malaysia ; 74(3): 240-242, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31256183

RESUMO

In central venous obstruction, vertebral marrow enhancement (VME) may be seen secondary to collateral venous flow via the vertebral venous plexus.1 There are only sporadic case reports on pseudolesions due to collateral enhancement mimicking sclerotic osseous metastasis. This abnormal vertebral enhancement may lead to erroneous diagnosis of sclerotic metastases or suspicious bone lesion which affect the management and prognosis. We describe a case of brachiocephalic vein obstruction-related vertebral body pseudolesions as identified in contrast-enhanced computed tomography (CECT) scan.


Assuntos
Veias Braquiocefálicas , Hiperemia/etiologia , Doenças Vasculares Periféricas/complicações , Doenças Vasculares Periféricas/diagnóstico , Estenose Espinal/diagnóstico , Idoso , Constrição Patológica , Diagnóstico Diferencial , Humanos , Masculino
9.
BMJ Open Respir Res ; 6(1): e000437, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354952

RESUMO

Background: Human enterovirus D68 (EV-D68) was first isolated in 1962 and has aroused public concern recently because of a nationwide outbreak among children in 2014-2015 in the USA. The symptoms include fever, runny nose, sneezing, cough and muscle pains. It might be associated with severe respiratory illness in individuals with pre-existing respiratory conditions and its potential association with acute flaccid myelitis is under investigation. In Asia, EV-D68 cases have been reported in several countries. The study: We aimed to understand the EV-D68 prevalence and their genetic diversity in Hong Kong children. Methods: A total of 10 695 nasopharyngeal aspirate (NPA) samples from hospitalised patients aged <18 years were collected from September 2014 to December 2015 in two regional hospitals. NPAs tested positive for enterovirus/rhinovirus (EV/RV) were selected for genotyping. For those identified as EV-D68, their complete coding sequences (CDSs) were obtained by Sanger sequencing. A maximum-likelihood phylogeny was constructed using all EV-D68 complete coding sequences available in GenBank (n=482). Results: 2662/10 695 (24.9%) were tested positive with EV/RV and 882/2662 (33.1%) were selected randomly and subjected to molecular classification. EV-D68 was detected in 15 (1.70%) samples from patients with clinical presentations ranging from wheezing to pneumonia and belonged to subclade B3. Eight CDSs were successfully obtained. A total of 10 amino acid residue polymorphisms were detected in the viral capsid proteins, proteases, ATPase and RNA polymerase. Conclusion: B3 subclade was the only subclade found locally. Surveillance of EV-D68 raises public awareness and provides the information to determine the most relevant genotypes for vaccine development.


Assuntos
Surtos de Doenças/prevenção & controle , Enterovirus Humano D/isolamento & purificação , Infecções por Enterovirus/epidemiologia , Infecções Respiratórias/epidemiologia , Adolescente , Criança , Pré-Escolar , Enterovirus Humano D/genética , Enterovirus Humano D/imunologia , Infecções por Enterovirus/prevenção & controle , Infecções por Enterovirus/virologia , Feminino , Genoma Viral/genética , Técnicas de Genotipagem , Hong Kong/epidemiologia , Humanos , Lactente , Masculino , Epidemiologia Molecular , Nasofaringe/virologia , Filogenia , RNA Viral/genética , RNA Viral/isolamento & purificação , Infecções Respiratórias/virologia , Sequenciamento Completo do Genoma
10.
Aust Vet J ; 97(8): 262-267, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31209859

RESUMO

OBJECTIVE: To determine the lesion distribution patterns in different breeds of dogs affected by atopic dermatitis in South Australia. METHODS: The presence or absence of erythematous skin lesions in 267 cases of canine atopic dermatitis (CAD) was recorded across 36 anatomical sites. Breeds represented by ≥ 9 dogs were included in the analysis. The percentage of dogs showing lesions at each of the body sites was calculated and illustrated on colour-coded diagrams. Variations in affected body sites within and between breeds were compared using Kruskal-Wallis ANOVA and Dunn's multiple comparison tests. RESULTS: The prevalence of skin lesions at different body sites differed significantly both in the population as a whole and within breeds. The sites affected in ≥ 75% dogs were the dorsal and ventral aspects of the front and hind paws. The sites affected in 50-74% were the medial pinnae, axillae, ventral chest, abdomen and perineum. Sites affected in 25-49% of dogs included the face, periocular region and forelimb. Remaining body sites were affected in < 25% of dogs. Analysis at the breed level revealed some differences from this standard distribution pattern. CONCLUSION: The results of this study confirmed the typical lesion distributions seen in CAD and highlighted some subtle differences in breeds commonly seen in South Australia. This will be useful for clinical practitioners in prioritising differential diagnoses for pruritic skin conditions.


Assuntos
Dermatite Atópica/veterinária , Doenças do Cão/epidemiologia , Animais , Dermatite Atópica/epidemiologia , Doenças do Cão/patologia , Cães , Feminino , Masculino , Linhagem , Prevalência , Austrália do Sul/epidemiologia
11.
Clin Nutr ; 38(4): 1700-1706, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30170780

RESUMO

BACKGROUND: Nutritional status can be difficult to assess. Bioelectrical impedance analysis (BIA)-derived phase angle (PA), and the plasma markers citrulline and transthyretin (pre-albumin) have the potential to assist, but the protocol of fasting and resting for BIA renders the investigation impractical for routine use, especially so in populations at high risk of malnutrition. AIMS: 1 To clarify whether starving and resting are necessary for reliable measurement of PA. 2 To identify whether PA, citrulline and transthyretin correlate with nutritional status. METHODS: Eighty consenting adult in-patients were recruited. Nutritional status was determined by subjective global assessment (SGA) used as gold standard. The Malnutrition Universal Screening Tool (MUST) was used and anthropometric measurements were performed. Serum was analysed for citrulline and transthyretin. PA was measured using Bodystat 4000. The PA was considered to define malnutrition when lower than reference ranges for sex and age, and severe malnutrition if more than 2 integers below the lower limit. Anthropometric measurements were categorised according to WHO reference centiles. Ordinal logistic regression estimated the strength of association of PA, citrulline and transthyretin with SGA. PA values in the different metabolic states were compared using paired t tests. RESULTS: All 80 subjects completed the BIA and the nutritional assessments in the 3 different states; 14 declined to provide blood samples for the biochemical assays. Malnutrition was identified in 32 cases, severe malnutrition in 14 cases, the remaining 34 cases were deemed not to be malnourished. PA was strongly inversely associated with SGA (Odds Ratio [OR] per unit increase = 0.21, CI 0.12-0.37, p < 0.001). PA was not influenced by exercise (p = 0.134) or food intake (p = 0.184). Transthyretin was inversely associated with malnourished/severely malnourished states (OR = 0.98, 95% CI 0.97-0.99, p = 0.001), but had poorer predictive values than PA. There was no significant association between citrulline concentration and SGA (OR = 1.01, 95% CI 0.99-1.04, p = 0.348). CONCLUSIONS: The BIA-derived PA reliably identifies malnutrition. It is strongly associated with SGA but requires less skill and experience, and out-performs circulating transthyretin, rendering it a promising and less operator-dependent tool for assessing nutritional status in hospital patients. Our novel demonstration that fasting and bed-rest are unnecessary consolidates that position.


Assuntos
Impedância Elétrica/uso terapêutico , Desnutrição/diagnóstico , Avaliação Nutricional , Estado Nutricional/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Composição Corporal/fisiologia , Citrulina/sangue , Estudos Transversais , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Pré-Albumina/análise , Adulto Jovem
12.
Eur J Cancer ; 108: 17-24, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30592991

RESUMO

BACKGROUND: Akt activation is common in gastric/gastroesophageal junction cancer (GC/GEJC) and is associated with chemotherapy resistance. Treatment with ipatasertib, a pan-Akt inhibitor, may potentiate the efficacy of chemotherapy in GC/GEJC. PATIENTS AND METHODS: In this randomised, double-blind, placebo-controlled, multicentre, phase II trial, patients with locally advanced or metastatic GC/GEJC not amenable to curative therapy were randomised 1:1 to receive ipatasertib or placebo, plus mFOLFOX6 (modified regimen of leucovorin, bolus and infusional 5-fluorouracil [5-FU], and oxaliplatin). The co-primary end-point was progression-free survival (PFS) in the intent-to-treat (ITT) population and in phosphatase and tensin homolog (PTEN)-low patients. Secondary end-points included PFS in patients with PI3K/Akt pathway-activated tumours; overall survival, investigator-assessed objective response rate and duration of response in the ITT population; and safety assessments. RESULTS: In 153 enrolled patients, the median PFS (ITT) was 6.6 months (90% confidence interval [CI], 5.7-7.5) with ipatasertib/mFOLFOX6 versus 7.5 months (90% CI, 6.2-8.1) with placebo/mFOLFOX6 (hazard ratio, 1.12; 90% CI, 0.81-1.55; P = 0.56). No statistically significant PFS benefit was observed in biomarker-selected patient subgroups (PTEN-low and PI3K/Akt pathway-activated tumours) with ipatasertib/mFOLFOX6 versus placebo/mFOLFOX6. Other secondary end-points did not favour the ipatasertib/mFOLFOX6 treatment arm. The percentages of patients with ≥1 adverse event (AE, 100% versus 98%) and grade ≥3 AEs (79% versus 74%) were similar between arms. Higher rates of AEs leading to treatment withdrawal (16% versus 6%) and serious AEs were reported in the ipatasertib arm (54% versus 43%). Thirty-nine and 29 deaths occurred in the ipatasertib and placebo arms, respectively. CONCLUSIONS: Ipatasertib/mFOLFOX6 compared with placebo/mFOLFOX6 did not improve PFS in unselected or biomarker-selected patients. No unexpected safety concerns were observed. TRIAL REGISTRATION: ClinicalTrials.gov (NCT01896531).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma/tratamento farmacológico , Junção Esofagogástrica , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Piperazinas/uso terapêutico , Pirimidinas/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/secundário , Carcinoma/secundário , Feminino , Fluoruracila/uso terapêutico , Humanos , Leucovorina/uso terapêutico , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/uso terapêutico , Intervalo Livre de Progressão , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Neoplasias Gástricas/patologia
13.
Clin Otolaryngol ; 42(6): 1311-1318, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28317337

RESUMO

OBJECTIVE: To explore the rationale for investigating patients presenting with globus symptoms. In this regard, we also assess the efficacy and safety of transnasal flexible laryngo-oesophagoscopy (TNFLO). METHODS: A prospective study in a head and neck cancer centre of patients with persistent globus symptoms with normal flexible nasoendoscopy/indirect mirror laryngoscopy and failure of first-line medical treatment. The role of TNFLO in investigating these patients was assessed. RESULTS: A total of 218 patients were recruited in this study. Positive findings included upper aerodigestive cancers in two patients, other pathologies included reflux (four patients), cricopharyngeus-related pathologies (19 patients), candida (five patients). There were only five re-referrals of patients who were discharged following normal examination with TNFLO. In nine patients, TNFLO could not be completed and they went on to have other diagnostic procedures CONCLUSION: This article is the largest to date in the UK to assess the role of TNFLO in investigating patients with globus symptoms. TNFLO is equal to rigid endoscopy as a diagnostic tool. However, it is superior in terms of image clarity, ability to record video images and safety.


Assuntos
Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/etiologia , Esofagoscopia , Laringoscopia , Cirurgia Endoscópica por Orifício Natural , Adulto , Idoso , Idoso de 80 Anos ou mais , Transtornos de Deglutição/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reino Unido , Adulto Jovem
14.
J Environ Radioact ; 165: 197-205, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27764678

RESUMO

A comprehensive series of nuclear tests were carried out by the United States at Enewetak Atoll in the Marshall Islands, especially between 1952 and 1958. A Porites Lutea coral that was growing in the Enewetak lagoon within a few km of all of the high-yield tests contains a continuous record of isotopes, which are of interest (e.g. 14C, 236U, 239,240Pu) through the testing period. Prior to the present work, 14C measurements at ∼2-month resolution had shown pronounced peaks in the Δ14C data that coincided with the times at which tests were conducted. Here we report measurements of 236U and 239,240Pu on the same coral using accelerator mass spectrometry, and again find prominent peaks in the concentrations of these isotopes that closely follow those in 14C. Consistent with the 14C data, the magnitudes of these peaks do not, however, correlate well with the explosive yields of the corresponding tests, indicating that smaller tests probably contributed disproportionately to the debris that fell in the lagoon. Additional information about the different tests can also be obtained from the 236U/239Pu and 240Pu/239Pu ratios, which are found to vary dramatically over the testing period. In particular, the first thermonuclear test, Ivy-Mike, has characteristic 236U/239Pu and 240Pu/239Pu signatures which are diagnostic of the first arrival of nuclear test material in various archives.


Assuntos
Antozoários/química , Plutônio/análise , Monitoramento de Radiação , Poluentes Radioativos da Água/análise , Animais , Micronésia , Armas Nucleares , Cinza Radioativa/análise
16.
Brain Inj ; 29(12): 1426-30, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26287759

RESUMO

PRIMARY OBJECTIVE: To assess the relationship between disability, length of stay (LOS) and anticholinergic burden (ACB) with people following acquired brain or spinal cord injury. RESEARCH DESIGN: A retrospective case note review assessed total rehabilitation unit admission. METHODS AND PROCEDURES: Assessment of 52 consecutive patients with acquired brain/spinal injury and neuropathy in an in-patient neuro-rehabilitation unit of a UK university hospital. Data analysed included: Northwick Park Dependency Score (NPDS), Rehabilitation complexity Scale (RCS), Functional Independence Measure and Functional Assessment Measure FIM-FAM (UK version 2.2), LOS and ACB. Outcome was different in RCS, NPDS and FIM-FAM between admission and discharge. MAIN OUTCOMES AND RESULTS: A positive change was reported in ACB results in a positive change in NPDS, with no significant effect on FIM-FAM, either Motor or Cognitive, or on the RCS. Change in ACB correlated to the length of hospital stay (regression correlation = -6.64; SE = 3.89). There was a significant harmful impact of increase in ACB score during hospital stay, from low to high ACB on NPDS (OR = 9.65; 95% CI = 1.36-68.64) and FIM-FAM Total scores (OR = 0.03; 95% CI = 0.002-0.35). CONCLUSIONS: There was a statistically significant correlation of ACB and neuro-disability measures and LOS amongst this patient cohort.


Assuntos
Antagonistas Colinérgicos/farmacologia , Tempo de Internação/tendências , Adulto , Idoso , Idoso de 80 Anos ou mais , Lesões Encefálicas/fisiopatologia , Lesões Encefálicas/reabilitação , Antagonistas Colinérgicos/efeitos adversos , Pessoas com Deficiência , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde/tendências , Recuperação de Função Fisiológica , Centros de Reabilitação , Estudos Retrospectivos , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/reabilitação
17.
Clin Exp Pharmacol Physiol ; 42(9): 888-895, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26173485

RESUMO

Sympatholytic and vasodilator drugs have been of major therapeutic benefit in patients with heart failure (HF). Urocortin-2 (Ucn2) is a small corticotrophin-related peptide distributed throughout the cardiovascular system which inhibits cardiac sympathetic nerve activity (CSNA) and is also a powerful vasodilator. This study analysed the effects of a 60-min infusion of Ucn2 (25 µg) on muscle sympathetic nerve activity (MSNA) recorded from the lower limb in eight healthy men and four men with stable HF. During Ucn2 infusion, mean arterial pressure fell to a nadir of 84 ± 2 compared to 95 ± 2 mmHg during placebo (P = 0.001) and heart rate increased to a maximum of 74 ± 1 compared to 64 ± 1 b.p.m. (P < 0.001). Total peripheral resistance fell by 23 ± 4% compared with an increase of 23 ± 4% (P < 0.001) and cardiac output increased by 22 ± 4 compared to 4 ± 4% (P = 0.001). The MSNA burst frequency increased by 9 ± 2 compared to 1 ± 2 burst/min (P = 0.005) and burst area/min by 133 ± 7 vs 107 ± 7% (P = 0.01). Burst incidence and baroreflex sensitivity were not significantly altered. Qualitatively similar changes were observed in stable HF patients. Ucn2-induced vasodilatation increased MSNA in humans, as opposed to the decrease in CSNA we observed in sheep. Therefore, if Ucn2 has a central inhibitory effect on MSNA, it was over-run by off-loading the cardiovagal baroreflex. Alternatively, CSNA may be less responsive to baroreflex off-loading than MSNA.

18.
Nat Commun ; 6: 6620, 2015 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-25782977

RESUMO

Current methods of chemical vapour deposition (CVD) of graphene on copper are complicated by multiple processing steps and by high temperatures required in both preparing the copper and inducing subsequent film growth. Here we demonstrate a plasma-enhanced CVD chemistry that enables the entire process to take place in a single step, at reduced temperatures (<420 °C), and in a matter of minutes. Growth on copper foils is found to nucleate from arrays of well-aligned domains, and the ensuing films possess sub-nanometre smoothness, excellent crystalline quality, low strain, few defects and room-temperature electrical mobility up to (6.0±1.0) × 10(4) cm(2) V(-1) s(-1), better than that of large, single-crystalline graphene derived from thermal CVD growth. These results indicate that elevated temperatures and crystalline substrates are not necessary for synthesizing high-quality graphene.

19.
J Intellect Disabil Res ; 59(7): 678-87, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25400206

RESUMO

BACKGROUND: Children with intellectual disability and specific learning disabilities often lack age-appropriate social skills, which disrupts their social functioning. Because of the limited effectiveness of classroom mainstreaming and social skills training for these children, it is important to explore alternative opportunities for social skill acquisition. Participation in social activities is positively related to children's social adjustment, but little is known about the benefits of activity participation for children with intellectual and specific learning disabilities. METHODS: This study investigated the association between frequency and type of social activity participation and the social competence of 8-11-year-old children with intellectual disability (n = 40) and specific learning disabilities (n = 53), in comparison with typically developing peers (n = 24). RESULTS: More time involved in unstructured activities, but not structured activities, was associated with higher levels of social competence for all children. This association was strongest for children with intellectual disability, suggesting that participation in unstructured social activities was most beneficial for these children. CONCLUSION: Future research on the quality of involvement is necessary to further understand specific aspects of unstructured activities that might facilitate social development.


Assuntos
Desenvolvimento Infantil/fisiologia , Deficiência Intelectual/psicologia , Deficiências da Aprendizagem/psicologia , Participação Social/psicologia , Habilidades Sociais , Criança , Feminino , Humanos , Masculino
20.
Pacing Clin Electrophysiol ; 37(7): 810-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24502608

RESUMO

BACKGROUND: We hypothesized that left atrial pressure (LAP) obtained by a permanent implantable sensor is sensitive to changes in cardiac resynchronization therapy (CRT) settings and could guide CRT optimization to improve the response rate. We investigated the effect of CRT optimization on LAP and its waveform parameters in ambulant heart failure (HF) patients. METHODS: CRT optimization was performed in eight ambulant HF patients, using echocardiography as reference. LAP waveform was acquired at each of eight atrioventricular (AV) intervals and five inter-ventricular (VV) intervals. Selected waveform parameters were also evaluated for their sensitivity to CRT changes and agreement with echocardiography-guided optimal settings. RESULTS: Optimal AV and VV intervals varied considerably between patients. All patients exhibited significant changes in waveform morphology with AV optimization. Optimal AV delay determined from echocardiography ranged between 140 ms and 225 ms. Mean LAP tended to be lower at optimal setting 14 ± 3 mmHg compared to shorter (<100 ms) or longer (>160 ms) AV settings (P = 0.16). There were clear trends to smaller peak a-wave (P = 0.11) and gentler positive a-slope (P = 0.15) and positive v-slope (P = 0.09) with longer AV delays. Mean LAP and negative v-wave slope correlated well with echo-guided optimal setting, r = 0.91 (P = 0.001) and 0.79 (P = 0.03), respectively. No significant effects on LAP or waveform were seen during VV optimization. CONCLUSIONS: LAP and its waveform changes considerably with AV optimization. There is good agreement between echo-guided optimal setting and LAP. LAP could provide an objective guide to CRT optimization. (Clinical Trial Registry information: URL: http://www.clinicaltrials.gov. Unique Identifier: NCT00632372).


Assuntos
Pressão Atrial , Terapia de Ressincronização Cardíaca/métodos , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Adulto , Idoso , Estudos de Viabilidade , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos
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