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1.
Proteins ; 92(2): 219-235, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37814578

RESUMO

Interleukin-4 (IL-4) is a hematopoietic cytokine composed by a four-helix bundle stabilized by an antiparallel beta-sheet and three disulfide bonds: Cys3-Cys127, Cys24-Cys65, and Cys46-Cys99. IL-4 is involved in several immune responses associated to infection, allergy, autoimmunity, and cancer. Besides its physiological relevance, IL-4 is often used as a "model" for protein design and engineering. Hence, to understand the role of each disulfide in the structure and dynamics of IL-4, we carried out several spectroscopic analyses (circular dichroism [CD], fluorescence, nuclear magnetic resonance [NMR]), and molecular dynamics (MD) simulations on wild-type IL-4 and four IL-4 disulfide mutants. All disulfide mutants showed loss of structure, altered interhelical angles, and looser core packings, showing that all disulfides are relevant for maintaining the overall fold and stability of the four-helix bundle motif, even at very low pH. In the absence of the disulfide connecting both protein termini Cys3-Cys127, C3T-IL4 showed a less packed protein core, loss of secondary structure (~9%) and fast motions on the sub-nanosecond time scale (lower S2 order parameters and larger τc correlation time), especially at the two protein termini, loops, beginning of helix A and end of helix D. In the absence of Cys24-Cys65, C24T-IL4 presented shorter alpha-helices (14% loss in helical content), altered interhelical angles, less propensity to form the small anti-parallel beta-sheet and increased dynamics. Simultaneously deprived of two disulfides (Cys3-Cys127 and Cys24-Cys65), IL-4 formed a partially folded "molten globule" with high 8-anilino-1-naphtalenesulphonic acid-binding affinity and considerable loss of secondary structure (~50%decrease), as shown by the far UV-CD, NMR, and MD data.


Assuntos
Dissulfetos , Interleucina-4 , Conformação Proteica , Interleucina-4/química , Dissulfetos/química , Estrutura Secundária de Proteína , Espectroscopia de Ressonância Magnética , Dicroísmo Circular
2.
Neurobiol Dis ; 196: 106518, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38679112

RESUMO

Resting tremor is the most common presenting motor symptom in Parkinson's disease (PD). The supplementary motor area (SMA) is a main target of the basal-ganglia-thalamo-cortical circuit and has direct, facilitatory connections with the primary motor cortex (M1), which is important for the execution of voluntary movement. Dopamine potentially modulates SMA and M1 activity, and both regions have been implicated in resting tremor. This study investigated SMA-M1 connectivity in individuals with PD ON and OFF dopamine medication, and whether SMA-M1 connectivity is implicated in resting tremor. Dual-site transcranial magnetic stimulation was used to measure SMA-M1 connectivity in PD participants ON and OFF levodopa. Resting tremor was measured using electromyography and accelerometry. Stimulating SMA inhibited M1 excitability OFF levodopa, and facilitated M1 excitability ON levodopa. ON medication, SMA-M1 facilitation was significantly associated with smaller tremor than SMA-M1 inhibition. The current findings contribute to our understanding of the neural networks involved in PD which are altered by levodopa medication and provide a neurophysiological basis for the development of interventions to treat resting tremor.


Assuntos
Antiparkinsonianos , Eletromiografia , Levodopa , Córtex Motor , Doença de Parkinson , Estimulação Magnética Transcraniana , Tremor , Humanos , Levodopa/uso terapêutico , Levodopa/farmacologia , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/fisiopatologia , Masculino , Córtex Motor/efeitos dos fármacos , Córtex Motor/fisiopatologia , Feminino , Tremor/fisiopatologia , Tremor/tratamento farmacológico , Idoso , Pessoa de Meia-Idade , Estimulação Magnética Transcraniana/métodos , Antiparkinsonianos/uso terapêutico , Antiparkinsonianos/farmacologia , Vias Neurais/fisiopatologia , Vias Neurais/efeitos dos fármacos , Potencial Evocado Motor/efeitos dos fármacos , Potencial Evocado Motor/fisiologia
3.
Transgenic Res ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856866

RESUMO

Plants evolved, over millions of years, complex defense systems against pathogens. Once infected, the interaction between pathogen effector molecules and host receptors triggers plant immune responses, which include apoptosis, systemic immune response, among others. An important protein family responsible for pathogen effector recognition is the nucleotide binding site-leucine repeat rich (NBS-LRR) proteins. The NBS-LRR gene family is the largest disease resistance gene class in plants. These proteins are widely distributed in vascular plants and have a complex multigenic cluster distribution in plant genomes. To counteract the genetic load of such a large gene family on fitness cost, plants evolved a mechanism using post transcriptional gene silencing induced by small RNAs, particularly microRNAs. For the NBS-LRR gene family, the small RNAs involved in this silencing mechanism are mainly the microRNA482/2118 superfamily. This suppression mechanism is relieved upon pathogen infection, thus allowing increased NBS-LRR expression and triggering plant immunity. In this review, we will discuss the biogenesis of microRNAs and secondary RNAs involved in this silencing mechanism, biochemical and structural features of NBS-LRR proteins in response to pathogen effectors and the evolution of microRNA-based silencing mechanism with a focus on the miR482/2118 family. Furthermore, the biotechnological manipulation of microRNA expression, using both transgenic or genome editing approaches to improve cultivated plants will be discussed, with a focus on the miR482/2118 family in soybean.

4.
Clin Radiol ; 79(5): 323-329, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38429136

RESUMO

Interstitial lung diseases (ILDs) are a heterogeneous group of conditions characterised by non-infective inflammation and scarring of the lung parenchyma. They are not infrequently encountered by the general radiologist in both acute and outpatient reporting settings who may even be the first to make the diagnosis. In the acute setting, patients with ILD can present with respiratory deterioration due to a number of causes and in addition to the common causes of dyspnoea, an acute exacerbation of ILD needs to be considered. An exacerbation can be initiated by common triggers such as infection, pulmonary embolism (PE), and heart failure, and it can also be initiated by an insult to the lung or occur due to an unknown cause. Particular care needs to be taken when interpreting computed tomography (CT) examinations in these patients as the findings of an acute exacerbation are non-specific and patient and technical factors can cause spurious appearances including dependent changes, breathing artefact and contrast medium opacification. In the non-acute setting, patients with ILD are at increased risk of lung cancer and pulmonary hypertension (PH), with lung cancer being a particularly important consideration as treatments carry the risk of triggering an acute exacerbation or deterioration in lung function. Overall, this review aims to provide an overview for the general radiologist of additional factors to consider when interpreting scans in patients with ILD and how the presence of ILD impacts the differential diagnoses and complications that can occur in these patients in both acute and non-acute settings.


Assuntos
Doenças Pulmonares Intersticiais , Neoplasias Pulmonares , Humanos , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Doenças Pulmonares Intersticiais/complicações , Pulmão/diagnóstico por imagem , Prognóstico , Dispneia , Progressão da Doença
5.
J Dairy Sci ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38608938

RESUMO

Our objective was to estimate the requirements of metabolizable energy (ME) and net energy for the maintenance (NEm) of lactating and dry cows, the efficiency of ME utilization for milk production (kl) and tissue gain (kg), and the use of body energy mobilization for milk production (kt) throughout the lactation of primiparous crossbred Holstein × Gyr cows, using open-circuit respiration chambers. Twenty-nine primiparous Holstein × Gyr crossbred cows with an initial BW averaging 563 ± 40.1 kg and 2.5 ± 0.09 years old were used throughout lactation and dry periods. The cows were kept non-pregnant throughout the study to eliminate possible confounding factors. Apparent digestibility assays, followed by calorimeter measurements, were performed 6 times throughout the lactation period. In the dry-off period, the cows were also evaluated but fed with restricted intake (DMI = 1.1% BW/d) to achieve heat production close to maintenance. After 21 d of diet adaptation, an apparent digestibility assay followed by calorimeter measurements was performed. Parameter estimates for lactation period were obtained by mixed models including lactation stage as repeated measures. For restricted feeding at dry-off and fasting period assays, the requirements were estimated by exponential regression. For whole lactation, the values of MEm and NEm were 0.588 and 0.395 MJ/BW0.75, respectively. The efficiencies klkgkt were 0.672, 0.771, and 0.814, respectively. However, MEm and NEm were higher in early and mid-lactation than late, while kl was higher in early than other lactation stages. Dry and non-pregnant cows had MEm of 0.434 MJ/BW0.75 and NEm of 0.351 MJ/BW0.75 for maintenance level, and MEm of 0.396 MJ/BW0.75 and NEm of 0.345 MJ/BW0.75 for fasting metabolism level and efficiency of ME utilization for maintenance was 0.80. Our findings confirmed that F1 crossbred Holstein × Gyr dairy cows have differences in energy requirement and efficiency throughout the lactation stages, suggesting the use of different values in each stage. The estimated values of energy requirement for maintenance and efficiencies for primiparous lactating crossbred Holstein × Gyr were similar to those reported in the literature in specific studies and requirements systems.

6.
Clin Radiol ; 78(12): 885-894, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37709611

RESUMO

Anterior mediastinal masses can be difficult to characterise on computed tomography (CT) due to the wide spectrum of normal appearances of thymic tissue as well as the challenge of differentiating between benign and malignant pathologies. Additionally, attenuation of cystic mediastinal lesions can be misinterpreted on CT due to varying attenuation values. Anecdotally, non-vascular magnetic resonance imaging (MRI) of the thorax is underutilised across radiology departments in the UK, but has been shown to improve diagnostic certainty and reduce unnecessary surgical intervention. T2-weighted MRI is useful in confirming the cystic nature of lesions, whereas chemical shift techniques can be utilised to document the presence of macroscopic and intra-cellular fat and thus help distinguish between benign and malignant pathologies. In this review article, we present a practical approach to using MRI for the characterisation of anterior mediastinal lesions based on our clinical experience in a UK district general hospital.


Assuntos
Neoplasias do Mediastino , Humanos , Neoplasias do Mediastino/diagnóstico por imagem , Neoplasias do Mediastino/patologia , Imageamento por Ressonância Magnética/métodos , Timo/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Mediastino/diagnóstico por imagem
7.
Clin Radiol ; 78(12): 947-954, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37718182

RESUMO

AIM: To determine the proportion of computed tomography (CT) coronary angiography (CTCA) referrals with coronary artery calcification (CAC) evident on previous non-cardiac CT imaging and how this impacted the diagnostic yield for CTCA, the requirement for additional diagnostic testing, and the associated costs to confirm or refute obstructive coronary artery disease (CAD). MATERIALS AND METHODS: A retrospective review of CTCA examinations was undertaken between 01/05/2018 and 31/05/2020 in which the examinations were cross referenced for previous non-gated thoracic CT at Royal United Hospitals Bath. Major epicardial vessel CAC on baseline CT was re-evaluated by published semi-quantitative methods, giving a per-patient CAC score (mild = 1-3, moderate = 4-6, severe >6). Subsequent incomplete CTCA diagnostic yield, further testing, and cost implications were examined. RESULTS: Of the 2140 CTCA examinations identified, 13% (280/2140) had a preceding non-gated thoracic CT (53% female, age 63 ± 11 years). The incomplete diagnostic rate increased with CAC grade, mild 32%, (RR 12; 95% CI 4-40), moderate 64% (RR 25; 95% CI 8-80), severe 75%, (RR 29; 95% CI 9-94). Additional diagnostic testing occurred in 4% for the mild CAC category, and 14% and 42% for moderate and severe, respectively. When severe CAC was identified on a non-gated thoracic CT a cost saving of £171/patient (dobutamine stress echo [DSE]) and £61/patient (myocardial perfusion scintigraphy [MPS]) was established with a direct to functional testing pathway. CONCLUSIONS: In patients referred for CTCA where severe CAC was identified on a preceding non-gated thoracic CT a direct to functional testing altered management in 42% of cases and was cost-effective.


Assuntos
Doença da Artéria Coronariana , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Masculino , Angiografia Coronária/métodos , Valor Preditivo dos Testes , Doença da Artéria Coronariana/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Angiografia por Tomografia Computadorizada/métodos
8.
Clin Radiol ; 78(6): 412-420, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36935258

RESUMO

AIMS: Guidelines have recommended reporting coronary artery calcification (CAC) if present on chest CT imaging regardless of indication. This study assessed CAC prevalence, prognosis and the potential clinical impact of its reporting. METHODS: We performed a single-centre retrospective analysis (January-December 2015) of 1400 chest CTs (200 consecutive within each age group: <40, 40-49, 50-59, 60-69, 70-79, 80-89, ≥90). CTs were re-reviewed for CAC presence and severity and excluded if prior coronary intervention. Comorbidities, statin prescription and clinical outcomes (myocardial infarction [MI], stroke, all-cause mortality) were recorded. The impact of reporting CAC was assessed against pre-existing statin prescriptions. RESULTS: 1343 patients were included (mean age 63±20 years, 56% female). Inter- and intra-observer variability for CAC presence at re-review was almost perfect (κ 0.89, p < 0.001; κ 0.90, p < 0.001) and for CAC grading was substantial and almost perfect (κ 0.68, p < 0.001; κ 0.91, p < 0.001). CAC was observed in 729/1343 (54%), more frequently in males (p < 0.001) and rising age (p < 0.001). A high proportion of patients with CAC in all age groups had no prior statin prescription (range: 42% [80-89] to 100% [<40]). The 'number needed to report' CAC presence to potentially impact management across all ages was 2. 689 (51%) patients died (median follow-up 74-months). CAC presence was associated with risk of MI, stroke and all-cause mortality (p < 0.001). After adjusting for confounders, severe calcification predicted risk of all-cause mortality (HR 1.8 [1.2-2.5], p = 0.002). CONCLUSION: Grading of CAC was reproducible, and although prevalence rose with age, prognostic and treatment implications were maintained in all ages.


Assuntos
Doença da Artéria Coronariana , Inibidores de Hidroximetilglutaril-CoA Redutases , Infarto do Miocárdio , Acidente Vascular Cerebral , Calcificação Vascular , Masculino , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Prognóstico , Estudos Retrospectivos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Vasos Coronários , Fatores de Risco , Medição de Risco/métodos , Calcificação Vascular/complicações , Doença da Artéria Coronariana/complicações , Tomografia Computadorizada por Raios X/métodos , Acidente Vascular Cerebral/complicações
9.
Appl Opt ; 62(18): 4935-4941, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37707271

RESUMO

The half-adder is one of the most useful combinational logic functions for data processing. Many research papers in the literature propose nonlinear all-optical half-adders. Few studies propose linear all-optical devices, and those that do usually employ microstructured 2D photonic crystals. This work presents the numerical acquisition of an all-optical half-adder using a linear three-core fiber device. The device presents high performance and acceptable values of fabrication and modulation tolerance. It can be made using any fiber technology and propagated by pulses of any wavelength. Depending on the type of fiber used, the precision needed to fabricate the device's smallest structures can range from 20 nm to 90 nm. This result is evidence of the possibility of obtaining nonlinear logical processing using only fiber design.

10.
Cryo Letters ; 44(4): 208-218, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37883138

RESUMO

BACKGROUND: The use of sulfated polysaccharides (PS) in seminal cooling is known to improve seminal quality. OBJECTIVE: To evaluate the effect of different concentrations of PS, extracted from the macroalgae Gracilaria domigensis as a supplement to the seminal cooling medium of the reophilic fish Prochilodus brevis (common curimatã). MATERIALS AND METHODS: Five semen pools were diluted in ACP-104 (treatment T1), in BTS® (T2) and in BTS® with different concentrations of PS (0.5 [T3]; 1.0 [T4] and 1.5 [T5]). The samples were cooled for different times (0, 6, 24, 48, 72, 96 and 120 h) and after each hour they were analyzed for: morphology, membrane integrity, DNA integrity and sperm kinetics. RESULTS: There were no significant differences between the treatments containing different concentrations of sulfated polysaccharides. Regarding the different cooling times, it was possible to observe that after hour 96, there was a reduction in the parameters of sperm kinetics. For DNA integrity there was no significant difference in relation to the treatments nor in relation to the hours. For membrane integrity, a reduction was noted as of hour 96, but there was no influence of polysaccharides. For the sperm morphology, there was no statistical difference between the hours, however the BTS was better than the ACP-104. CONCLUSION: It is concluded that the use of polysaccharides in seminal cooling has no negative effect on sperm parameters and proves that seminal cooling keeps the material viable for up to 72 hours. Doi: 10.54680/fr23410110512.


Assuntos
Caraciformes , Preservação do Sêmen , Animais , Masculino , Sêmen , Motilidade dos Espermatozoides , Sulfatos , Criopreservação , Espermatozoides , DNA , Suplementos Nutricionais
11.
Cerebellum ; 21(1): 23-38, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33880658

RESUMO

Dual-site transcranial magnetic stimulation (TMS) can be used to measure the cerebellar inhibitory influence on the primary motor cortex, known as cerebellar brain inhibition (CBI), which is thought to be important for motor control. The aim of this study was to determine whether age-related differences in CBI (measured at rest) were associated with an age-related decline in bilateral motor control measured using the Purdue Pegboard task, the Four Square Step Test, and a 10-m walk. In addition, we examined test re-test reliability of CBI measured using dual-site TMS with a figure-of-eight coil in two sessions. There were three novel findings. First, CBI was less in older than in younger adults, which is likely underpinned by an age-related loss of Purkinje cells. Second, greater CBI was associated with faster 10-m walking performance in older adults, but slower 10-m walking performance in younger adults. Third, moderate intraclass correlation coefficients (ICCs: 0.53) were found for CBI in younger adults; poor ICCs were found for CBI (ICC: 0.40) in older adults. Together, these results have important implications for the use of dual-site TMS to increase our understanding of age- and disease-related changes in cortical motor networks, and the role of functional connectivity in motor control.


Assuntos
Córtex Motor , Estimulação Magnética Transcraniana , Cerebelo/fisiologia , Potencial Evocado Motor/fisiologia , Córtex Motor/fisiologia , Reprodutibilidade dos Testes , Estimulação Magnética Transcraniana/métodos
12.
Clin Radiol ; 77(12): 913-919, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36167569

RESUMO

Medical imaging is a multidisciplinary specialty, combining clinical expertise from medical physics, radiography, and radiology, and plays a key role in patient care. Research is vital to ensure the care delivered to patients is evidence-based, and is a core component of clinical governance; however, there are pressures on the imaging workforce, which are significantly impeding imaging research. This commentary presents a research gap analysis pertaining to the multidisciplinary imaging workforce on behalf of the National Institute for Health Research (NIHR) Imaging Workforce Group. Data were summarised from membership surveys of the Royal College of Radiologists, Society and College of Radiographers, and Institute of Physics and Engineering in Medicine; national reports; and feedback from NIHR Clinical Research Network Imaging Champions meeting in 2020/2021. Common barriers to delivering research were found across the multidisciplinary workforce. The key issues were lack of staff, lack of time, and lack of funding to backfill clinical services. Given the ongoing workforce shortages and increasing clinical demands on radiologists, diagnostic radiographers, and medical physicists, these issues must be tackled with a high priority to ensure the future of clinical research within the NHS.


Assuntos
Radiologia , Medicina Estatal , Humanos , Recursos Humanos , Diagnóstico por Imagem , Reino Unido
13.
Clin Radiol ; 77(7): e500-e508, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35487778

RESUMO

AIM: To determine the diagnostic accuracy of an automated artificial intelligence derived right ventricle/left ventricle diameter ratio (RV/LV) computed tomography pulmonary angiography (CTPA) analysis tool to detect pulmonary hypertension (PH) in patients with suspected PH referred to a specialist centre. MATERIALS AND METHODS: The present study was a retrospective analysis of a prospectively maintained database of 202 consecutive patients with suspected PH, who underwent CTPA within 12 months of right heart catheterisation (RHC). Automated ventricular segmentation and RV/LV calculation (Imbio LLC, Minneapolis, MN, USA) was undertaken on the CTPA images. PH diagnosis was made using the RHC reference standard. RESULTS: The automated RV/LV correlated more strongly with RHC metrics than main pulmonary artery (MPA) diameter and MPA to ascending aorta diameter ratio (MPA/AA) measured manually (mean pulmonary arterial pressure [mPAP] r=0.535, R2 = 0.287 p<0.001; pulmonary vascular resistance [PVR] r=0.607, R2 = 0.369 p<0.001). In the derivation cohort (n=100), the area under the receiver-operating curve for automated RV/LV discriminating PH was 0.752 (95% confidence interval [CI] 0.677-0.827, p<0.001). Using an optimised Youden's Index of ≥1.12 classified from derivation, automated RV/LV ratio analysis was more sensitive for the detection of PH with higher positive predictive value (PPV) when compared with manual MPA and MPA/AA in the validation cohort (n=102). Automated RV/LV compromise (1.12) and specific (1.335) thresholds were strongly predictive of mortality (log-rank 7.401, p=0.007 and log-rank 16.075, p<0.001 respectively). CONCLUSION: In suspected PH, automated RV/LV diameter thresholds have high sensitivity for PH, outperform manual MPA and MPA/AA and can predict survival.


Assuntos
Hipertensão Pulmonar , Angiografia/métodos , Inteligência Artificial , Cateterismo Cardíaco , Ventrículos do Coração/diagnóstico por imagem , Humanos , Hipertensão Pulmonar/diagnóstico por imagem , Artéria Pulmonar/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
14.
Clin Radiol ; 77(5): e379-e386, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35303990

RESUMO

AIM: To assess the relationship of global longitudinal strain during left atrial (LA) and left ventricular (LV) filling and emptying. MATERIALS AND METHODS: Using magnetic resonance imaging in 47 hypertensive patients, biplane global LV longitudinal strain was evaluated and related to LA and LV filling and emptying (by volumetric analysis), and to pulmonary vein and trans-mitral flow (by phase-contrast imaging). The results were compared to normal subjects. RESULTS: In hypertensive patients, reduced global longitudinal LV strain was associated with reduced LA reservoir (47 ± 10 versus 53 ± 9%, p<0.05), reduced LA conduit function (21 ± 9 versus 32 ± 11%, p<0.004), reduced LA early peak emptying rate (150 ± 77 versus 230 ± 88 ml/s, p=0.007), and slower early LV filling (373 ± 141 versus 478 ± 141 ml/s, p=0.03). LA peak filling rate showed a positive correlation to LV peak emptying rate (R=0.331, p=0.02). CONCLUSION: In hypertensive heart disease, impaired LV longitudinal systolic function causes reduced LA filling and emptying, and this leads directly to impaired LV filling and diastolic dysfunction.


Assuntos
Hipertensão , Disfunção Ventricular Esquerda , Função do Átrio Esquerdo , Ecocardiografia/métodos , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/patologia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Hipertensão/complicações , Hipertensão/diagnóstico por imagem , Hipertensão/patologia , Disfunção Ventricular Esquerda/complicações
15.
Appl Opt ; 61(28): 8515-8521, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36256168

RESUMO

Digital multiplexers/demultiplexers (MUX/DEMUXes) are essential for computing, data transmission, and data processing. However, research on all-optical digital MUX/DEMUXes is scarce and generally proposes single-function nonlinear devices. This work presents the numerical acquisition of all-optical digital MUX/DEMUXes using a linear three-core fiber device. Our device, called the interchanging-cores planar three-core fiber coupler, is propagated by low-powered amplitude modulated pulses, can operate with pulses of any wavelength, and can be made using any fiber technology. This result is further evidence of the possibility of obtaining logical processing, even nonlinear logical processing, using fiber-only design.

16.
J Dairy Sci ; 105(5): 4421-4433, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35282915

RESUMO

Bovine anaplasmosis causes considerable economic losses in dairy cattle production systems worldwide, ranging from $300 million to $900 million annually. It is commonly detected through rectal temperature, blood smear microscopy, and packed cell volume (PCV). Such methodologies are laborious, costly, and difficult to systematically implement in large-scale operations. The objectives of this study were to evaluate (1) rumination and activity data collected by Hr-Tag sensors (SCR Engineers Ltd.) in heifer calves exposed to anaplasmosis; and (2) the predictive ability of recurrent neural networks in early identification of anaplasmosis. Additionally, we aimed to investigate the effect of time series length before disease diagnosis (5, 7, 10, or 12 consecutive days) on the predictive performance of recurrent neural networks, and how early anaplasmosis disease can be detected in dairy calves (5, 3, and 1 d in advance). Twenty-three heifer calves aged 119 ± 15 (mean ± SD) d and weighing 148 ± 20 kg of body weight were challenged with 2 × 107 erythrocytes infected with UFMG1 strain (GenBank no. EU676176) isolated from Anaplasma marginale. After inoculation, animals were monitored daily by assessing PCV. The lowest PCV value (14 ± 1.8%) and the finding of rickettsia on blood smears were used as a criterion to classify an animal as sick (d 0). Rumination and activity data were collected continuously and automatically at 2-h intervals, using SCR Heatime Hr-Tag collars. Two time series were built including last sequence of -5, -7, -10, or -12 d preceding d 0 or a sequence of 5, 7, 10, or 12 d randomly selected in a window from -50 to -15 d before d 0 to ensure a sequence of days in which PCV was considered normal (32 ± 2.4%). Long short-term memory was used as a predictive approach, and a leave-one-animal-out cross-validation (LOAOCV) was used to assess prediction quality. Anaplasmosis disease reduced 34 and 11% of rumination and activity, respectively. The accuracy, sensitivity, and specificity of long short-term memory in detecting anaplasmosis ranged from 87 to 98%, 83 to 100%, and 83 to 100%, respectively, using rumination data. For activity data, the accuracy, sensitivity, and specificity varied from 70 to 98%, 61 to 100%, and 74 to 100%, respectively. Predictive performance did not improve when combining rumination and activity. The use of longer time-series did not improve the performance of models to predict anaplasmosis. The accuracy and sensitivity in predicting anaplasmosis up to 3 d before clinical diagnosis (d 0) were greater than 80%, confirming the possibility for early identification of anaplasmosis disease. These findings indicate the great potential of wearable sensors in early identification of anaplasmosis diseases. This could positively affect the profitability of dairy farmers and animal welfare.


Assuntos
Anaplasma marginale , Anaplasmose , Doenças dos Bovinos , Anaplasmose/diagnóstico , Anaplasmose/microbiologia , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/microbiologia , Eritrócitos , Feminino , Vacinação/veterinária
17.
Eur Ann Allergy Clin Immunol ; 54(4): 168-174, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33944542

RESUMO

Summary: Background. Acute urticaria is a common condition in the pediatric emergency department (ED) and no data is available in Portugal. Objective. We aimed to characterize the prevalence, etiology and management of acute urticaria in children presenting at an ED of a portuguese central hospital and report the follow-up investigation when drug or food allergy was suspected.Methods. Retrospective study of clinical records from children admitted to the ED with acute urticaria during one year period. Results. 250 children were included, mean age of 7.4 ± 4.9 years (0-17 years). The most frequently suspected etiological factors were infections (22%), foods (12%), insect bites (9%) and drugs (8%), of which, upper respiratory tract infections, seafood and ß-lactam antibiotics were the most frequent. In 44% of cases, the etiology of urticaria was not determined. After ED discharge, of the 50 patients with suggestive drug or food allergy, only 48% were sent to allergological workup and the allergy confirmed in 6 of them (2.4% of the 250 children). Conclusions. These data suggest that allergy is not the main trigger of acute urticaria in ED children, but when suspected, reference to an allergy department to complete allergological workup was insufficient.


Assuntos
Hipersensibilidade Alimentar , Urticária , Criança , Pré-Escolar , Serviço Hospitalar de Emergência , Hipersensibilidade Alimentar/diagnóstico , Hipersensibilidade Alimentar/epidemiologia , Hipersensibilidade Alimentar/terapia , Hospitais , Humanos , Encaminhamento e Consulta , Estudos Retrospectivos , Urticária/diagnóstico , Urticária/epidemiologia , Urticária/terapia
18.
Cryo Letters ; 43(2): 110-119, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36626152

RESUMO

BACKGROUND: Using sulfated polysaccharides (SP) in fish sperm freezing medium promotes cell maintenance. OBJECTIVE: To evaluate the effect of different SP concentrations, extracted from two seaweeds (Gracilaria domingensis and Ulva fasciata), as a supplement to the sperm freezing medium of Prochilodus brevis. MATERIALS AND METHODS: Five semen pools were diluted in a solution composed of 5% glucose, 10 % dimethyl sulfoxide (DMSO) and different SP concentrations (0, 0.5, 1.0, 1.5, 2.0, 2.5 or 3.0 mg/mL). The samples were cryopreserved and, after 7 days, rewarmed and analyzed for morphology, plasma membrane integrity, DNA integrity, mitochondrial activity and sperm kinetics [total motility, progressive motility, curvilinear velocity (VCL), straight line velocity (VSL), average path velocity (VAP), linearity (LIN), and wobble (WOB)]. RESULTS: There was no interaction between seaweed and SP concentrations. Similar effects were observed with SP extracted from the two seaweeds, regardless of concentration. When comparing the SP concentrations, regardless of the seaweed, 1.0 mg/mL SP showed better results for VCL and VSL. For VAP and WOB, 1.0 mg/mL SP showed better results, but differed from 3.0 mg/mL. LIN followed the same pattern, but differed from SP at 2.5 and 3.0 mg/mL. For progressive motility, 1.0 mg/mL G. domingensis showed superior results compared to the control. For mitochondrial activity, G. domingensis was superior to U. fasciata, regardless of concentration. The lowest concentrations (0.5 and 1.0 mg/mL) showed the best results, regardless of the seaweed. However, the control was superior to all treatments tested. CONCLUSION: G. domingensis SP at the lowest concentrations might be a potential supplement to the P. brevis freezing medium. doi.org/10.54680/fr22210110412.


Assuntos
Caraciformes , Preservação da Fertilidade , Preservação do Sêmen , Animais , Masculino , Congelamento , Criopreservação/métodos , Sulfatos , Motilidade dos Espermatozoides , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Espermatozoides , Glucose
19.
Br J Dermatol ; 184(5): 935-943, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32790068

RESUMO

BACKGROUND: Loose anagen hair is a rare form of impaired hair anchorage in which anagen hairs that lack inner and outer root sheaths can be gently and painlessly plucked from the scalp. This condition usually occurs in children and is often self-limiting. A genetic basis for the disorder has been suggested but not proven. A better understanding the aetiology of loose anagen hair may improve prevention and treatment strategies. OBJECTIVES: To identify a possible genetic basis of loose anagen hair using next-generation DNA sequencing and functional analysis of variants identified. METHODS: In this case study, whole-exome sequencing analysis of a pedigree with one affected individual with features of loose anagen hair was performed. RESULTS: The patient was found to be compound heterozygous for two single-nucleotide substitutions in TKFC resulting in the following missense mutations: c.574G> C (p.Gly192Arg) and c.682C> T (p.Arg228Trp). Structural analysis of human TKFC showed that both mutations are located near the active site cavity. Kinetic assays of recombinant proteins bearing either of these amino acid substitutions showed almost no dihydroxyacetone kinase or D-glyceraldehyde kinase activity, and FMN cyclase activity reduced to just 10% of wildtype catalytic activity. CONCLUSIONS: TKFC missense mutations may predispose to the development of loose anagen hairs. Identification of this new biochemical pathobiology expands the metabolic and genetic basis of hypotrichosis.


Assuntos
Doenças do Cabelo , Hipotricose , Alopecia , Criança , Cabelo , Doenças do Cabelo/genética , Humanos , Hipotricose/genética , Mutação de Sentido Incorreto
20.
Clin Radiol ; 76(11): 801-811, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34404515

RESUMO

Cardiovascular disease (CVD) is the leading cause of death in the UK, whilst millions live with various forms of the disease. Coronary artery disease constitutes a significant portion of this morbidity and mortality, and is the leading cause of premature death. Increasing focus is thus being placed on the optimisation of CVD prevention, where risk screening plays a key role. Indeed, the decline in age-adjusted cardiovascular mortality achieved up to now has been largely attributed to primary preventative therapies (e.g., statins) introduced earlier in the disease process. National initiatives exist to improve cardiovascular health at a population level, but in its current form, CVD screening at the individual level is predominantly undertaken using multivariate risk scores based on population-based data. These have multiple innate flaws, highlighted in this review. Non-invasive imaging plays a key role in the screening of other disease processes, helping to personalise the screening process. Although the coronary artery calcium score as a screening tool has a role in national and international guidance, whether a shift to screening with computed tomography coronary angiography (CTCA) is now appropriate is open for discussion. Image acquisition techniques continue to improve with reducing radiation exposure and an ever-expanding evidence-base for additional prognostic data offered by CTCA. This enables the potential identification of sub-clinical atherosclerosis, including with novel artificial intelligence techniques. This review aims to report current guidelines regarding cardiac CT imaging in the asymptomatic primary prevention setting, advances in various CT technologies and future opportunities for progress in this field.


Assuntos
Doenças Cardiovasculares/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Angiografia Coronária/métodos , Humanos , Medição de Risco
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