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1.
Spinal Cord ; 60(10): 882-887, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35523952

RESUMO

STUDY DESIGN: Mixed-method study (small group discussions and online literature search). OBJECTIVES: Identify the ethical issues and dilemmas faced by rehabilitation professionals involved in the service delivery to the persons with spinal cord injury (SCI) in the low income and lower-middle-income countries (LIC/LMIC) located in Asia. SETTING: Small group discussions in three biomedical conferences in Dhaka, Bangladesh and Kualalampur, Malaysia. METHODS: Three small group discussions (30-45 min each) were held during three international conferences in 2019. The conferences brought together experts in the fields of neurology, rehabilitation, neurorehabilitation, and bioethics. A summary of SCI practice points and dilemmas were documented including goals of care, duties of rehabilitation professionals, health care worker-patient relationships, roles, and expectations of family members at different care settings. RESULTS: There is a paucity of literature on this topic. The application of the principles of contemporary bioethics in the pluralistic societies of LIC/LMIC can be challenging. The ethical dilemmas faced by rehabilitation professionals working in LIC/LMIC are diverse and different from those reported from the Western and developed countries. Ethical issues and dilemmas identified were understanding patient autonomy in decision making, lack of insurance for SCI rehabilitation, financial challenges, challenges of providing emerging technology in SCI rehabilitation and SCI rehabilitation during disasters. CONCLUSIONS: We have summarized the possible ethical issues and dilemmas which rehabilitation professionals in LIC/LMIC may encounter during delivery of SCI rehabilitation services. We hope it generates a discussion on an often-neglected aspect of SCI care in the LIC/LMIC and helps identify the complexities of ethical dilemmas unique to persons with SCI living in a developing country.


Assuntos
Reabilitação Neurológica , Traumatismos da Medula Espinal , Ásia , Bangladesh , Ética , Pessoal de Saúde , Humanos , Reabilitação Neurológica/ética , Traumatismos da Medula Espinal/reabilitação
2.
Sensors (Basel) ; 22(7)2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35408106

RESUMO

A 32-bit chipless RFID tag operating in the 4.5-10.9 GHz band is presented in this paper. The tag has a unique multiple-arc-type shape consisting of closely packed 0.2 mm wide arcs of different radii and lengths. The specific tag geometry provides multiple resonances in frequency domain of an RCS plot. A frequency domain coding technique has also been proposed to encode the tag's RCS signature into a 32-bit digital identification code. The tag has an overall dimension of 17.9 × 17.9 mm2, resulting in a high code density of 9.98 bits/cm2 and spectral efficiency of 5 bits/GHz. The proposed tag is built on a low loss substrate bearing a very small footprint, thereby making it extremely suitable for large-scale product identification purposes in future chipless RFID tag systems.


Assuntos
Dispositivo de Identificação por Radiofrequência , Dispositivo de Identificação por Radiofrequência/métodos
3.
J Appl Microbiol ; 131(5): 2433-2447, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33896080

RESUMO

AIMS: The present research aimed to examine the use of magnetite nanoparticles (MNPs) in combination with phyto-beneficial rhizobacterium (PhBR) for improvement of applied N recovery (ANR) from urea fertilizer in rice grown under deficient and optimum watering conditions. METHODS AND RESULTS: The Bacillus sp. MR-1/2 was positive for acetylene reduction, phosphate solubilization and ACC deaminase activity at temperature ranges 35-45°C. In a pot experiment, urea, MNPs and Bacillus sp. MR-1/2 were applied either alone or in combination to rice plants grown in pots under water deficit and optimal watering conditions. Combined application of urea, MNPs and Bacillus sp. MR-1/2 increased the plant N content and ANR by 27 and 65%, respectively, over their respective control values in rice grown under optimum watering conditions, whereas these increases were 27 and 41%, respectively, in rice grown under water deficit conditions. This treatment also increased the kernel weight and plant dry matter by 36 and 60%, respectively, over control (urea alone) values in rice grown under water deficit conditions, whereas these increases were 31 and 21·8%, respectively, in rice grown under optimum watering conditions. Values of malondialdehyde (MDA) contents, ascorbate peroxidase (APX), catalase and ethylene concentration were higher in control treatment under both the watering regimes. The application of Bacillus sp. MR-1/2 either alone or in combination with MNPs and urea reduced MDA contents, APX, catalase and ethylene production in the rice plants. CONCLUSION: The combined application of MNPs+Bacillus sp. MR-1/2 reduced the N losses from applied urea, increased N uptake and ANR in rice, decreased MDA contents, APX and catalase activity and ethylene level in rice grown under deficit and optimum water conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: The application of MNPs together with Bacillus sp. MR-1/2 may help to increase ANR and rice productivity under water deficit conditions with low cost of production.


Assuntos
Bacillus , Nanopartículas de Magnetita , Oryza , Fertilizantes , Nitrogênio , Ureia , Água
4.
Adv Exp Med Biol ; 1343: 21-37, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35015275

RESUMO

Persian Medicine (PM) or Humoral Medicine is a traditional school of medicine with thousands of years of prolific history. The concept of Mizaj (temperament) and hot-cold theory is one of PM's most important foundations. In the clinical setting, Mizaj represents individual differences in phenotypical, psychological, spiritual, and physiological functions. Mizaj has a crucial role in determining the treatment plan, to the point that a similar disease in patients with different Mizaj types may demand different treatments. In this chapter, the role of hot and cold theory in the diagnosis and treatment of diseases to develop an integrative medical approach is discussed.


Assuntos
Medicina Tradicional , Temperamento , Humanos
5.
Nanotechnology ; 31(50): 504001, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33021239

RESUMO

Stochastic neuromorphic computation (SNC) has the potential to enable a low power, error tolerant and scalable computing platform in comparison to its deterministic counterparts. However, the hardware implementation of complementary metal oxide semiconductor (CMOS)-based stochastic circuits involves conversion blocks that cost more than the actual processing circuits. The realization of the activation function for SNCs also requires a complicated circuit that results in a significant amount of power dissipation and area overhead. The inherent probabilistic switching behavior of nanomagnets provides an advantage to overcome these complexity issues for the realization of low power and area efficient SNC systems. This paper presents magnetic tunnel junction (MTJ)-based stochastic computing methodology for the implementation of a neural network. The stochastic switching behavior of the MTJ has been exploited to design a binary to stochastic converter to mitigate the complexity of the CMOS-based design. The paper also presents the technique for realizing stochastic sigmoid activation function using an MTJ. Such circuits are simpler than existing ones and use considerably less power. An image classification system employing the proposed circuits has been implemented to verify the effectiveness of the technique. The MTJ-based SNC system shows area and energy reduction by a factor of 13.5 and 2.5, respectively, while the prediction accuracy is 86.66%. Furthermore, this paper investigates how crucial parameters, such as stochastic bitstream length, number of hidden layers and number of nodes in a hidden layer, need to be set precisely to realize an efficient MTJ-based stochastic neural network (SNN). The proposed methodology can prove a promising alternative for highly efficient digital stochastic computing applications.

6.
J Appl Microbiol ; 129(3): 575-589, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32147927

RESUMO

OBJECTIVE: The present study was performed to examine the role of pqqE inhabiting rhizobacteria in organic acid production and relationship of the organic acids with phosphate solubilization by the bacteria in vitro as well as in vivo. METHODS AND RESULTS: The pqqE gene was PCR amplified and sequenced in genomic DNA of Pantoea sp. WP-5 and Pseudomonas sp. NN-4. Nucleotide sequence obtained from WP-5 and NN-4 showed maximum sequence similarity (88 and 89%, respectively) with the pqqE gene of Pseudomonas fluorescens strain CMR12a (KM251420). Deduced amino acid sequence from pqqE gene of Pseudomonas sp. NN-4 and Pantoea sp. WP-5 showed 75 and 93% similarity, respectively, with protein pyrroloquinoline quinone. Phosphate solubilization and acid production assay were quantified on spectrophotometer and high-profile liquid chromatograph, respectively, by each bacterial strain. Both strains produced organic acids such as acetic, citric, gluconic, succinic and malic acid and lowered the pH of Pikovskaya broth medium under laboratory conditions. Phosphate solubilization by Pantoea sp. WP-5 was 311 ± 4 and 204 ± 3 µg ml-1 in the culture medium supplemented with glucose and sucrose as carbon source, respectively. Pseudomonas sp. NN-4 solubilized 176 ± 3 and 298 ± 5 µg ml-1 phosphate in Pikovskaya broth medium under similar conditions. In field experiments conducted during two consecutive years, the concentration of acetic acid and gluconic acid was higher in root exudates of plants treated with Pantoea sp. WP-5 at 30% reduced doses of nitrogen (N)- and phosphorus (P)-based chemical fertilizers as compared to non-inoculated plants. Values of chlorophyll contents, crop growth rate, leaf area index, straw yield and P contents were recorded higher in plants inoculated with Pantoea sp. WP-5 and Pseudomonas sp. NN-4 as compared to non-inoculated control. Grain yield was increased by 10-12% due to inoculation with Pantoea sp. WP-5 and Pseudomonas sp. NN-4 over non-inoculated control in the field experiments. CONCLUSIONS: These results lead to the conclusions that the rhizobacteria inhabiting pqqE gene produced organic acids and solubilized the phosphate in vitro. On inoculation to wheat plants in field experiments, these strains produced the organic acids, solubilized the phosphate, and improved the P uptake and productivity of wheat. SIGNIFICANCE AND IMPACT OF THE STUDY: The Pantoea sp. WP-5 and Pseudomonas sp. NN-4 are the potential candidates for inoculation to wheat as phosphate solubilizer even with reduced chemical fertilizer dose. The inoculation of the strains may enhance grain yield and net income of the farmer even with less chemical fertilizer application. This practice will be helpfull inminimizing environmental pollution.


Assuntos
Proteínas de Bactérias/genética , Pantoea/fisiologia , Pseudomonas/fisiologia , Triticum/crescimento & desenvolvimento , Triticum/microbiologia , Ácidos/metabolismo , Proteínas de Bactérias/metabolismo , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Fertilizantes/análise , Pantoea/genética , Pantoea/metabolismo , Fosfatos/metabolismo , Pseudomonas/genética , Pseudomonas/metabolismo , Solo/química , Microbiologia do Solo , Triticum/metabolismo
7.
Am J Gastroenterol ; 114(1): 155-164, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30353057

RESUMO

OBJECTIVES: Intraductal papillary mucinous neoplasms (IPMNs) are associated with risk of pancreatic ductal adenocarcinoma (PDAC). It is unclear if an IPMN in individuals at high risk of PDAC should be considered as a positive screening result or as an incidental finding. Stratified familial pancreatic cancer (FPC) populations were used to determine if IPMN risk is linked to familial risk of PDAC. METHODS: This is a cohort study of 321 individuals from 258 kindreds suspected of being FPC and undergoing secondary screening for PDAC through the European Registry of Hereditary Pancreatitis and Familial Pancreatic Cancer (EUROPAC). Computerised tomography, endoscopic ultrasound of the pancreas and magnetic resonance imaging were used. The risk of being a carrier of a dominant mutation predisposing to pancreatic cancer was stratified into three even categories (low, medium and high) based on: Mendelian probability, the number of PDAC cases and the number of people at risk in a kindred. RESULTS: There was a median (interquartile range (IQR)) follow-up of 2 (0-5) years and a median (IQR) number of investigations per participant of 4 (2-6). One PDAC, two low-grade neuroendocrine tumours and 41 cystic lesions were identified, including 23 IPMN (22 branch-duct (BD)). The PDAC case occurred in the top 10% of risk, and the BD-IPMN cases were evenly distributed amongst risk categories: low (6/107), medium (10/107) and high (6/107) (P = 0.63). CONCLUSIONS: The risk of finding BD-IPMN was independent of genetic predisposition and so they should be managed according to guidelines for incidental finding of IPMN.


Assuntos
Carcinoma/epidemiologia , Predisposição Genética para Doença , Neoplasias Pancreáticas/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/genética , Carcinoma/patologia , Estudos de Coortes , Detecção Precoce de Câncer , Europa (Continente)/epidemiologia , Família , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Linhagem , Sistema de Registros , Fatores de Risco , Adulto Jovem
8.
World J Surg ; 43(6): 1604-1611, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30815742

RESUMO

BACKGROUND: Autoimmune pancreatitis (AIP) is an uncommon form of chronic pancreatitis. Whilst being corticosteroid responsive, AIP often masquerades radiologically as pancreatic neoplasia. Our aim is to appraise demographic, radiological and histological features in our cohort in order to differentiate AIP from pancreatic malignancy. METHODS: Clinical, biochemical, histological and radiological details of all AIP patients 1997-2016 were analysed. The initial imaging was re-reviewed according to international guidelines by three blinded independent radiologists to evaluate features associated with autoimmune pancreatitis and pancreatic cancer. RESULTS: There were a total of 45 patients: 25 in type 1 (55.5%), 14 type 2 (31.1%) and 6 AIP otherwise not specified (13.3%). The median (IQR) age was 57 (51-70) years. Thirty patients (66.6%) were male. Twenty-six patients (57.8%) had resection for suspected malignancy and one for symptomatic chronic pancreatitis. Three had histologically proven malignancy with concurrent AIP. Two patients died from recurrent pancreatic cancer following resection. Multidisciplinary team review based on radiology and clinical history dictated management. Resected patients (vs. non-resected group) were older (64 vs. 53, p = 0.003) and more frequently had co-existing autoimmune pathologies (22.2 vs. 55.6%, p = 0.022). Resected patients also presented with less classical radiological features of AIP, which are halo sign (0/25 vs. 3/17, p = 0.029) and loss of pancreatic clefts (18/25 vs. 17/17, p = 0.017). There were no differences in demographic features other than age. CONCLUSION: Despite international guidelines for diagnosing AIP, differentiation from pancreatic cancer remains challenging. Resection remains an important treatment option in suspected cancer or where conservative treatment fails.


Assuntos
Doenças Autoimunes/diagnóstico , Neoplasias Pancreáticas/diagnóstico , Pancreatite Crônica/diagnóstico , Adulto , Idoso , Antígenos Glicosídicos Associados a Tumores/sangue , Doenças Autoimunes/terapia , Biomarcadores/sangue , Estudos de Coortes , Diagnóstico Diferencial , Feminino , Glucocorticoides/uso terapêutico , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Pâncreas/diagnóstico por imagem , Neoplasias Pancreáticas/terapia , Pancreatite Crônica/terapia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
9.
Arch Phys Med Rehabil ; 100(8): 1492-1498, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30831091

RESUMO

OBJECTIVE: To identify all published protocols and reviews in the Cochrane Library relevant to the scope of practice of rehabilitation; to test pragmatic criteria to identify rehabilitation interventions; to begin categorizing reviews according to the professionals involved in delivering the intervention and broad areas of clinical practice. DATA SOURCES: Cochrane Database of Systematic Reviews. STUDY SELECTION: We screened all published reviews and protocols in the Cochrane library. DATA EXTRACTION: We built an online relational database into which we imported titles and abstracts of all reviews and protocols published in the Cochrane Library from 1996 to August 2018. We recruited rehabilitation professionals worldwide through Cochrane Rehabilitation's social media to find and tag rehabilitation reviews in this database. One rehabilitation physician and 1 allied health professional independently tagged each title against prespecified criteria. The Cochrane Rehabilitation Review Committee examined disagreements between contributors for any uncertainties about how to categorize a review. We revised and improved our preliminary criteria for identifying rehabilitation interventions as the work progressed. DATA SYNTHESIS: We identified that 9.4% of all Cochrane publications (894/9471 reviews and protocols) are directly relevant to the practice of rehabilitation. The professional groups whose interventions were most frequently the subject of rehabilitation reviews and protocols were rehabilitation physicians and physical therapists. We also identified a final list of inclusion and exclusion criteria for reviews on rehabilitation interventions. CONCLUSION: Many Cochrane Reviews are directly relevant to rehabilitation. Cochrane needs to consider the rehabilitation community a major stakeholder in all its work. The pragmatic criteria we tested are offered for future discussions on the identification and categorization of rehabilitation interventions by stakeholders worldwide. This work will support the spread of content from the Cochrane Library to rehabilitation professionals and guide future research.


Assuntos
Reabilitação , Literatura de Revisão como Assunto , Bases de Dados Factuais , Humanos
10.
Biophys J ; 115(6): 1082-1092, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-30195938

RESUMO

Often considered an archetypal dimeric coiled coil, tropomyosin nonetheless exhibits distinctive "noncanonical" core residues located at the hydrophobic interface between its component α-helices. Notably, a charged aspartate, D137, takes the place of nonpolar residues otherwise present. Much speculation has been offered to rationalize potential local coiled-coil instability stemming from D137 and its effect on regulatory transitions of tropomyosin over actin filaments. Although experimental approaches such as electron cryomicroscopy reconstruction are optimal for defining average tropomyosin positions on actin filaments, to date, these methods have not captured the dynamics of tropomyosin residues clustered around position 137 or elsewhere. In contrast, computational biochemistry, involving molecular dynamics simulation, is a compelling choice to extend the understanding of local and global tropomyosin behavior on actin filaments at high resolution. Here, we report on molecular dynamics simulation of actin-free and actin-associated tropomyosin, showing noncanonical residue D137 as a locus for tropomyosin twist variation, with marked effects on actin-tropomyosin interactions. We conclude that D137-sponsored coiled-coil twisting is likely to optimize electrostatic side-chain contacts between tropomyosin and actin on the assembled thin filament, while offsetting disparities between tropomyosin pseudorepeat and actin subunit periodicities. We find that D137 has only minor local effects on tropomyosin coiled-coil flexibility, (i.e., on its flexural mobility). Indeed, D137-associated overtwisting may actually augment tropomyosin stiffness on actin filaments. Accordingly, such twisting-induced stiffness of tropomyosin is expected to enhance cooperative regulatory translocation of the tropomyosin cable over actin.


Assuntos
Actinas/metabolismo , Tropomiosina/química , Tropomiosina/metabolismo , Sequência de Aminoácidos , Simulação de Dinâmica Molecular , Ligação Proteica , Conformação Proteica em alfa-Hélice
11.
Echocardiography ; 35(10): 1499-1506, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29943870

RESUMO

BACKGROUND: Software-based beamforming which utilizes delay and standard beamforming is a signal processing technique that temporarily stores data from each probe element to improve specular reflections to improve the image resolution. We compared a software algorithm which uses delay and standard beamforming with delay and sum beamforming in standard, hardware to evaluate endocardial borders and need for echo contrast. METHODS: In this prospective study, eligible participants were ≥18 years of age referred clinically for transthoracic echocardiograms. A limited study consisting of three views (apical 4, apical 3, and apical 2 chamber) was performed with the software-based beamforming and standard platform. Number and quality of segments visualized were evaluated using a 17-segment model. Quality of segments was graded as 0 = not visualized, 1 = incompletely visualized, or 2 = completely visualized. Overall quality score for each study (0 = poor, 1 = adequate, 2 = good) was reported. The need for contrast was determined by ASE guidelines. RESULTS: A total of 101 patients (mean age 61 ± 16 years, males 52%) were enrolled. Mean number of segments visualized in apical 4- (6.28 vs 5.65, P < .001), apical 3- (6.27 vs 5.54, P < .001), and apical 2-chamber views (6.26 vs 5.72 P < .001) was higher with the software vs standard platform. The average overall score for image quality was significantly better for the software platform vs standard (1.4 vs 0.9, P =< .001). With the software platform, 23% were judged as requiring contrast as compared with 45% for the standard platform (P < .001). CONCLUSIONS: Delay and standard beamforming in software platform identified more segments with better image quality when compared to the standard high-end platform, decreasing the need for contrast usage.


Assuntos
Algoritmos , Ecocardiografia/métodos , Endocárdio/diagnóstico por imagem , Cardiopatias/diagnóstico por imagem , Processamento de Sinais Assistido por Computador , Endocárdio/fisiopatologia , Feminino , Cardiopatias/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
12.
Echocardiography ; 35(5): 611-620, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29605969

RESUMO

BACKGROUND: Midwall fibrosis and low stroke volume are independent predictors of mortality in severe aortic stenosis (AS) with preserved LV ejection fraction (LVEF). The role of speckle tracking echocardiography (STE) to identify latent myopathy pre- and post- aortic valve replacement (AVR) in high risk AS patients with normal LVEF is limited. METHODS: Demographic, 2D echocardiographic, and STE data were analyzed in patients with severe AS and preserved LVEF who underwent tissue AVR. Velocity vector imaging (VVI) was used to assess regional and global peak systolic longitudinal strain (GLS). Low flow (LF) was defined as an indexed LV stroke volume <35 mL/m2 . RESULTS: Between December 2008 and May 2011, 37 patients (75 ± 9 years, 51% male) had both pre- and post-AVR echos within 6.6 ± 6.5 months (median = 4 months; range = 2.5-9.5) of surgery. Compared with pre-AVR, GLS (-6.9 ± 4.9% vs -11.1 ± 4.1%; P < .001) and strain rate (-0.72 ± 0.3s-1 vs -0.87 ± 0.3s-1 ; P = .01) improved post-AVR. Pre-AVR mid-segments showed a similar myopathy as the basal segments (-9.5 ± 4.3% vs -9.0 ± 4.2%;P = .3). The 16 (43%) LF patients in this study had lower pre- and post-AVR strain compared to NF patients (GLS Pre-AVR:LF vs NF: -5.1 ± 4.1% vs -8.4 ± 4.9% (P = .04) and GLS Post-AVR:LF vs NF: -9.2 ± 3.7% vs -12.5 ± 3.9% (P = .01)). However, there was no difference in absolute and %change improvement in GLS post-AVR (LF vs NF:∆ -4.2 ± 3.5% vs ∆-4.1 ± 5.3% (P = .90) and 193 ± 214% vs 143 ± 230% change (P = .5)). The lowest GLS was seen in LF/HG AS followed by LF/LG, NF/LG and NF/HG AS; P = .03. CONCLUSIONS: Latent myopathy is more pronounced in LF AS both pre- and post-AVR. Our study provides evidence of improvement in myopathy in LF AS despite a persistent worse myopathy compared to NF patients post-AVR.


Assuntos
Estenose da Valva Aórtica/complicações , Valva Aórtica/cirurgia , Velocidade do Fluxo Sanguíneo/fisiologia , Cardiomiopatias/etiologia , Implante de Prótese de Valva Cardíaca , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/cirurgia , Cardiomiopatias/diagnóstico , Cardiomiopatias/fisiopatologia , Ecocardiografia Doppler em Cores , Humanos , Estudos Multicêntricos como Assunto , Prognóstico , Estudos Retrospectivos
13.
Biophys J ; 113(11): 2444-2451, 2017 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-29211998

RESUMO

Elongated tropomyosin, associated with actin-subunits along the surface of thin filaments, makes electrostatic interactions with clusters of conserved residues, K326, K328, and R147, on actin. The association is weak, permitting low-energy cost regulatory movement of tropomyosin across the filament during muscle activation. Interestingly, acidic D292 on actin, also evolutionarily conserved, lies adjacent to the three-residue cluster of basic amino acids and thus may moderate the combined local positive charge, diminishing tropomyosin-actin interaction and facilitating regulatory-switching. Indeed, charge neutralization of D292 is connected to muscle hypotonia in individuals with D292V actin mutations and linked to congenital fiber-type disproportion. Here, the D292V mutation may predispose tropomyosin-actin positioning to a myosin-blocking state, aberrantly favoring muscle relaxation, thus mimicking the low-Ca2+ effect of troponin even in activated muscles. To test this hypothesis, interaction energetics and in vitro function of wild-type and D292V filaments were measured. Energy landscapes based on F-actin-tropomyosin models show the mutation localizes tropomyosin in a blocked-state position on actin defined by a deeper energy minimum, consistent with augmented steric-interference of actin-myosin binding. In addition, whereas myosin-dependent motility of troponin/tropomyosin-free D292V F-actin is normal, motility is dramatically inhibited after addition of tropomyosin to the mutant actin. Thus, D292V-induced blocked-state stabilization appears to disrupt the delicately poised energy balance governing thin filament regulation. Our results validate the premise that stereospecific but necessarily weak binding of tropomyosin to F-actin is required for effective thin filament function.


Assuntos
Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Tropomiosina/metabolismo , Actinas/química , Actinas/genética , Cálcio/metabolismo , Humanos , Modelos Moleculares , Mutação , Miosinas/metabolismo , Ligação Proteica , Conformação Proteica em alfa-Hélice , Eletricidade Estática , Termodinâmica
14.
J Nucl Cardiol ; 24(3): 946-951, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28205073

RESUMO

This review summarizes key imaging studies that were presented in the American Heart Association Scientific Sessions 2016 related to the fields of nuclear cardiology, cardiac computed tomography, cardiac magnetic resonance, and echocardiography. This bird's eye view will inform readers about multiple studies from these different modalities. We hope that this general overview will be useful for those that did not attend the conference as well as to those that did since it is often difficult to get exposure to many abstracts at large meetings. The review, therefore, aims to help readers stay updated on the newest imaging studies presented at the meeting.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Imagem Multimodal/métodos , Imagem Multimodal/tendências , Imagem de Perfusão do Miocárdio/métodos , Imagem de Perfusão do Miocárdio/tendências , Tomografia Computadorizada de Emissão/métodos , Tomografia Computadorizada de Emissão/tendências , Medicina Baseada em Evidências , Humanos , Estados Unidos
15.
Br J Sports Med ; 51(14): 1081-1086, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27601450

RESUMO

BACKGROUND: The Nine Plus screening battery test (9+) is a functional movement test intended to identify limitations in fundamental movement patterns predisposing athletes to injury. However, the interseason variability is unknown. AIM: To examine the variability of the 9+ test between 2 consecutive seasons in professional male football players. METHODS: Asymptomatic Qatar Star League players (n=220) completed the 9+ at the beginning of the 2013 and 2014 seasons. Time-loss injuries in training and matches were obtained from the Aspetar Injury and Illness Surveillance Program. No intervention was initiated between test occasions. RESULTS: A significant increase in the mean total score of 1.6 points (95% CI 1.0 to 2.2, p<0.001) was found from season 1 (22.2±4.1 (SD)) to season 2 (23.8±3.3). The variability was large, as shown by an intraclass correlation coefficient (ICC) of 0.24 (95% CI 0.11 to 0.36) and a minimal detectable change (MDC) of 8.7 points. Of the 220 players, 136 (61.8%) suffered a time-loss injury between the 2 tests. There was an improvement in mean total scores in the injured (+2.0±0.4 (SE), p<0.001) group but not in the uninjured group (+0.9±0.5, p=0.089). The variability from season 1 to season 2 was large both in the injured (ICC 0.25, 0.09 to 0.40, MDC 8.3) and uninjured (ICC 0.24, 0.02 to 0.43, MDC 9.1) groups. CONCLUSIONS: The 9+ demonstrated substantial intraindividual variability in the total score between 2 consecutive seasons, irrespective of injury. A change above 8 points is necessary to represent a real change in the 9+ test between seasons.


Assuntos
Atletas , Traumatismos em Atletas/epidemiologia , Movimento , Futebol/lesões , Adulto , Traumatismos em Atletas/diagnóstico , Humanos , Masculino , Valor Preditivo dos Testes , Estudos Prospectivos , Catar , Estações do Ano , Adulto Jovem
16.
Environ Monit Assess ; 189(3): 122, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28236149

RESUMO

Physico-chemical groundwater (GW) parameters were evaluated to understand the hydrogeochemical processes in the Siwalik plains of Jammu and Kashmir, India. During the 2012-2013 post-monsoon (POM) and pre-monsoon (PRM) seasons, GW samples (n = 207) from deep bore wells and shallow open wells were chemically analysed. Cations (Ca2+, Mg2+, Na+, K+ and Fe2+) and anions (HCO3-, Cl-, SO42- and F-) showed a wide spatio-temporal variation. Results suggest that weathering and dissolution of carbonates and silicate rocks is the main source of water mineralization. The major hydrochemical facies is characterized by Ca-Mg-HCO3 and Ca-HCO3 during the PRM and POM seasons respectively. The presence of sulphate-bearing water in a large number of the samples indicates a significant role of gypsum dissolution and anthropogenic contamination of the GW. Factor analysis (FA) and hierarchical cluster analysis (HCA) revealed that the variability of hydrochemistry is mainly related to rock-water interaction, dissolution of carbonates and other lithological units as well as the influence of anthropogenic activities in the area. Overall, it was found that the GW quality is within the limits of human consumption. The higher concentration of a few chemicals indicates an increasing trend of industrial contamination of the GW. For sustainable development of the portable GW in Siwaliks, it is necessary to minimize the adverse impacts of the anthropogenic and industrial contamination on the GW resources through best management practices and prevent its further contamination to a level that could make GW unsuitable for human uses.


Assuntos
Monitoramento Ambiental/métodos , Água Subterrânea/química , Poluentes Químicos da Água/análise , Carbonatos/análise , Humanos , Índia , Estações do Ano , Qualidade da Água
17.
J Nucl Cardiol ; 23(2): 235-43, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26818142

RESUMO

Multiple novel studies were presented at the 2015 American Heart Association Scientific Sessions which was considered a successful conference at many levels. In this review, we will summarize key studies in nuclear cardiology, cardiac magnetic resonance, echocardiography, and cardiac computed tomography that were presented at the Sessions. We hope that this bird's eye view will keep readers updated on the newest imaging studies presented at the meeting whether or not they were able to attend the meeting.


Assuntos
Coração/diagnóstico por imagem , Imagem Multimodal , American Heart Association , Angiografia por Tomografia Computadorizada , Circulação Coronária , Ecocardiografia , Humanos , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Estados Unidos
18.
Sensors (Basel) ; 16(12)2016 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-27929450

RESUMO

An inkjet-printed, fully passive sensor capable of either humidity or gas sensing is presented herein. The sensor is composed of an interdigitated electrode, a customized printable gas sensitive ink and a specialized dipole antenna for wireless sensing. The interdigitated electrode printed on a paper substrate provides the base conductivity that varies during the sensing process. Aided by the porous nature of the substrate, a change in relative humidity from 18% to 88% decreases the electrode resistance from a few Mega-ohms to the kilo-ohm range. For gas sensing, an additional copper acetate-based customized ink is printed on top of the electrode, which, upon reaction with hydrogen sulphide gas (H2S) changes, both the optical and the electrical properties of the electrode. A fast response time of 3 min is achieved at room temperature for a H2S concentration of 10 ppm at a relative humidity (RH) of 45%. The passive wireless sensing is enabled through an antenna in which the inner loop takes care of conductivity changes in the 4-5 GHz band, whereas the outer-dipole arm is used for chipless identification in the 2-3 GHz band.

19.
Biol Sport ; 33(1): 49-56, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26985134

RESUMO

This study assessed selected measures of cognitive function in trained cyclists who observed daylight fasting during Ramadan. Eleven cyclists volunteered to participate (age: 21.6±4.8 years, VO2max: 57.7±5.6 ml kg(-1)·min(-1)) and were followed for 2 months. Cognitive function (Cambridge Neuropsychological Test Automated Battery (CANTAB), Reaction Time index (RTI) and Rapid Visual Information Processing (RVP) tests) and sleep architecture (ambulatory EEG) were assessed: before Ramadan (BR), in the 1st week (RA1) and 4th week of Ramadan (RA4), and 2 weeks post-Ramadan (PR). Both cognitive tests were performed twice per day: before and after Ramadan at 8-10 a.m. and 4-6 p.m., and during Ramadan at 4-6 p.m. and 0-2 a.m., respectively. Training load (TL) by the rating of perceived exertion (RPE) method and wellness (Hooper index) were measured daily. If the TL increased over the study period, this variable was stable during Ramadan. The perceived fatigue and delayed onset muscle soreness (DOMS) increased at RA4. Sleep patterns and architecture showed clear disturbances, with significant increases in the number of awakenings and light sleep durations during Ramadan (RA1 and RA4), together with decreased durations of deep and REM sleep stages at PR. RTI (simple and multiple reaction index) reaction and movement times did not vary over the study period. The RVP test showed reduced false alarms during Ramadan, suggesting reduced impulsivity. Overall accuracy significantly increased at RA1, RA4 and PR compared to baseline. At RA4, the accuracy was higher at 0-2 a.m. compared to 4-6 p.m. Despite the observed disturbances in sleep architecture, Ramadan fasting did not negatively impact the cognitive performance of trained cyclists from the Middle East.

20.
J Nucl Cardiol ; 22(2): 364-71, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25698480

RESUMO

A large number of studies were presented at the 2014 American Heart Association Scientific Sessions. In this review, we will summarize key studies in nuclear cardiology, computed tomography, echocardiography, and cardiac magnetic resonance imaging. This brief review will be helpful for readers of the Journal who are interested in being updated on the latest research covering these imaging modalities.


Assuntos
Doenças Cardiovasculares/diagnóstico , Aumento da Imagem/métodos , Imagem Multimodal/métodos , Imagem de Perfusão do Miocárdio/métodos , Imagem de Perfusão do Miocárdio/tendências , Humanos
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