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1.
Tomography ; 9(2): 589-602, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36961007

RESUMO

A murine model of myelofibrosis in tibia was used in a co-clinical trial to evaluate segmentation methods for application of image-based biomarkers to assess disease status. The dataset (32 mice with 157 3D MRI scans including 49 test-retest pairs scanned on consecutive days) was split into approximately 70% training, 10% validation, and 20% test subsets. Two expert annotators (EA1 and EA2) performed manual segmentations of the mouse tibia (EA1: all data; EA2: test and validation). Attention U-net (A-U-net) model performance was assessed for accuracy with respect to EA1 reference using the average Jaccard index (AJI), volume intersection ratio (AVI), volume error (AVE), and Hausdorff distance (AHD) for four training scenarios: full training, two half-splits, and a single-mouse subsets. The repeatability of computer versus expert segmentations for tibia volume of test-retest pairs was assessed by within-subject coefficient of variance (%wCV). A-U-net models trained on full and half-split training sets achieved similar average accuracy (with respect to EA1 annotations) for test set: AJI = 83-84%, AVI = 89-90%, AVE = 2-3%, and AHD = 0.5 mm-0.7 mm, exceeding EA2 accuracy: AJ = 81%, AVI = 83%, AVE = 14%, and AHD = 0.3 mm. The A-U-net model repeatability wCV [95% CI]: 3 [2, 5]% was notably better than that of expert annotators EA1: 5 [4, 9]% and EA2: 8 [6, 13]%. The developed deep learning model effectively automates murine bone marrow segmentation with accuracy comparable to human annotators and substantially improved repeatability.


Assuntos
Aprendizado Profundo , Mielofibrose Primária , Humanos , Animais , Camundongos , Processamento de Imagem Assistida por Computador/métodos , Mielofibrose Primária/diagnóstico por imagem , Tíbia/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos
2.
Cureus ; 15(3): e36081, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37056537

RESUMO

Background/aim Heart transplantation is often the only preferable treatment for end-stage heart failure (HF); however, there are insufficient organ donors in Saudi Arabia. In this study, we aimed to understand the desire and readiness of Taif populations for heart donation after death. Methods We carried out a descriptive cross-sectional study among Taif residents in November 2022. A questionnaire designed from a previous survey was distributed among the participants. The questionnaire included sociodemographic data and questions assessing their desire for heart donation. Results The study included 405 subjects who have accepted to participate in the study. About half of the participants were aged 18 to 32 years (43.5%), most were females, were non-employed, and had a university degree. Of them, 86.2% accepted the concept of organ transplantation, 81% accepted the concept of heart transplantation, and one-third of the participants desired to donate their hearts. The participants with a university degree reported significantly less acceptance of the concept of heart transplantation (p-value=0.026), and those employed showed a significantly stronger desire for organ donation to a relative after death (p-value=0.049). In addition, younger participants showed a significantly higher willingness for organ donation to a relative or non-relative after death (p-value=0.017 and 0.009, respectively). Employed participants were significantly more willing to undergo heart transplantation surgery if needed (p-value=0.044). Conclusion Awareness campaigns could be established in the community and popularized during contact with the health system to build trust in the organ donation system, stress the importance of heart donation in saving the lives of more patients, and reduce the shortage of organ transplantation.

3.
PLoS One ; 17(5): e0265300, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35609033

RESUMO

Mental disorders, especially schizophrenia, still pose a great challenge for diagnosis in early stages. Recently, computer-aided diagnosis techniques based on resting-state functional magnetic resonance imaging (Rs-fMRI) have been developed to tackle this challenge. In this work, we investigate different decision-level and feature-level fusion schemes for discriminating between schizophrenic and normal subjects. Four types of fMRI features are investigated, namely the regional homogeneity, voxel-mirrored homotopic connectivity, fractional amplitude of low-frequency fluctuations and amplitude of low-frequency fluctuations. Data denoising and preprocessing were first applied, followed by the feature extraction module. Four different feature selection algorithms were applied, and the best discriminative features were selected using the algorithm of feature selection via concave minimization (FSV). Support vector machine classifiers were trained and tested on the COBRE dataset formed of 70 schizophrenic subjects and 70 healthy subjects. The decision-level fusion method outperformed the single-feature-type approaches and achieved a 97.85% accuracy, a 98.33% sensitivity, a 96.83% specificity. Moreover, feature-fusion scheme resulted in a 98.57% accuracy, a 99.71% sensitivity, a 97.66% specificity, and an area under the ROC curve of 0.9984. In general, decision-level and feature-level fusion schemes boosted the performance of schizophrenia detectors based on fMRI features.


Assuntos
Imageamento por Ressonância Magnética , Esquizofrenia , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Descanso , Máquina de Vetores de Suporte
4.
Cureus ; 14(7): e27014, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35989784

RESUMO

INTRODUCTION:  The admission of patients on weekends in multiple health centers has been associated with poorer outcomes relative to care provided during regular weekday hours. This study aimed to assess and compare the health outcomes of patients discharged on weekends and weekdays after undergoing surgery in a tertiary hospital in Taif, Saudi Arabia. MATERIALS AND METHODS: The data of patients were collected from hospital records in a retrospective manner, and the outcomes were assessed after discharge. Patients discharged on Friday and Saturday were considered weekend discharges, and those discharged on other days were considered weekday discharges. Data related to readmission and emergency department (ED) visits included the primary diagnosis, number of days post-primary discharge, length of stay, chief complaint, and the number of ED visits. A logistic regression model was done to assess the predictive factor for 30-readmission after surgery.  Results: The frequency of discharge over the weekend was 9.1%. About 6.5% and 7.3% were found to have 30-day readmission and 30-day ED visits, respectively. A statistically significant association was not observed between weekend discharge and the development of postoperative complications (p>0.05). A multinomial logistic regression showed that patients who had emergency admission, postoperative complications, and the presence of cancer were found to be independently associated with 30-day readmission after discharge (P<0.05). CONCLUSION:  Proactive strategies to reduce costly readmissions after surgery can be designed once the high-risk patient subset is identified.

5.
Cureus ; 14(12): e32460, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36644104

RESUMO

Background Postoperative hypoparathyroidism has been investigated in health records and surgical cohorts, but the results have been highly variable and imprecise. It is not clear how often endocrinologists encounter this hormone deficit in clinical practice. Thus, the aim of this study is to determine the incidence of permanent hypoparathyroidism and the factors associated with it in a group of post-thyroidectomy patients followed at three tertiary care institutions in Taif city. Materials and Methods A retrospective cohort analysis was done to examine patients who had a total thyroidectomy in the city of Taif between January 1, 2015, and December 31, 2019. Patients were eligible for the study if they received total thyroidectomy, were above the age of 18 years, had surgical and pathological data available, and had been monitored in the same institution for at least a year after their thyroidectomy. Patients who did not return for follow-up care following surgery were excluded from the study. Results The incidence of hypoparathyroidism was 10.3%, and females had a higher prevalence (12.1%) than males (3.2%). In patients with two and three parathyroid glands, hypoparathyroidism was found to be more prevalent (33.3% and 25.5%) in permanent histological sections. There was no single independent risk factor for hypoparathyroidism according to a logistic regression model. Conclusion The incidence rate of hypoparathyroidism following total thyroidectomy was about 10.3%. There were no independent risk factors identified for hypoparathyroidism after total thyroidectomy. Permanent hypoparathyroidism severely affects the quality of life, and research should be done to prevent its incidence after thyroidectomy.

6.
Biomacromolecules ; 12(3): 609-16, 2011 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-21319812

RESUMO

The layer-by-layer (LbL) technique has been widely used to produce nanofilms for biomedical applications. Naturally occurring polymers such as ECM macromolecules are attractive candidates for LbL film preparation. In this study, we assessed the build-up of type I collagen (Col1)/chondroitin sulfate (CS) or Col1/Heparin (HN) on polydimethylsiloxane (PDMS) substrates. The build-up was assessed by quartz crystal microbalance with dissipation (QCM-D) and atomic force microscopy (AFM). Integrin-mediated cell adhesion was assessed by studying the cytoskeletal organization of mammalian primary cells (chondrocytes) seeded on different end layers and number of layers. Data generated from the QCM-D observations showed a consistent build-up of films with more adsorption in the case of Col1/HN. Col1/CS films were stable in media, whereas Col1/HN films were not. AFM analysis showed that the layers were fibrillar in structure for both systems and between 20 and 30 nm thick. The films promoted cell adhesion when compared with tissue culture plastic in serum-free media with cycloheximide. Crosslinking of the films resulted in constrained cell spreading and a ruffled morphology. Finally, beta1 integrin blocking antibodies prevented cell spreading, suggesting that cell adhesion and spreading were mediated mainly by interaction with the collagen fibrils. The ability to construct stable ECM-based films on PDMS has particular relevance in mechanobiology, microfluidics, and other biomedical applications.


Assuntos
Materiais Biocompatíveis/síntese química , Condrócitos/citologia , Matriz Extracelular/química , Silicones/química , Adsorção , Animais , Adesão Celular , Sulfatos de Condroitina , Colágeno Tipo I , Heparina , Substâncias Macromoleculares/química , Membranas Artificiais , Camundongos
7.
Open Access Rheumatol ; 9: 139-150, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28814904

RESUMO

BACKGROUND: Even after achieving tremendous advances in diagnosis and treatment of rheumatoid arthritis (RA), many of the patients undergo delays in diagnosis and initiation of treatment, which leads to worsening of the condition and poor prognosis. OBJECTIVE: The objective of this study was to perform a literature review to quantify the lag times in diagnosis and treatment of RA and study the reported factors associated with it. METHODS: The authors searched literature published until September 2016 in electronic full-text and abstract databases and hand-searched the suitable articles. RESULTS: The weighted average of median lag time from symptom onset to therapy was 11.79 months (12 studies, 5,512 patients, range 3.6-24.0 months). Lag1 was 3.14 months (onset of symptoms to first physician consultant; 12 studies, 6,055 patients, range 0-5.7 months); lag2 was 2.13 months (physician visit to RA specialist referral; 13 studies, 34,767 patients, range 0.5-6.6 months); lag3 was 2.91 months (consultation with rheumatologist to diagnosis; 3 studies, 563 patients, range 0-5 months), lag4 was 2.14 months (diagnosis to initiation of disease-modifying antirheumatic drug therapy; 5 studies, 30,685 patients, range 0-2.2 months). Numerous patient-and physician-related factors like gender, ethnicity, primary care physician knowledge of the condition, availability of diagnostics, and so on were responsible for the delays. CONCLUSION: This review estimated the delay times and identified the main factors for delay in RA patients in diagnosis and initiation of treatment. A most plausible solution to this is coordinated effort by the rheumatology and primary care physicians.

8.
J Biomed Mater Res A ; 79(4): 874-81, 2006 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-16886216

RESUMO

Coatings of quaternary ammonium tertiary structures (QUATS) copolymerized with 4-vinylbenzylthymine (VBT) exhibited high antimicrobial activity against Escherichia coli. Immobilization of QUATS improves environmental performance by preventing release of antibacterials to the environment, helping to preclude the emergence of resistant strains. The crosslinking immobilization scheme reported herein provides a more environmentally benign and more inexpensive synthesis than previously reported, thus reducing the use of solvents, energy, and production time. Development of water soluble, thymine-based photopolymers was inspired by the UV-induced 2pi + 2pi photocyclodimerization of thymine in DNA. Copolymers of 4-vinylbenzylthymine and trimethylammonium chloride, triethylammonium chloride, or dimethyloctylammonium chloride were synthesized in different monomer ratios. The antibacterial properties were tested by coating VBT:QUATS in sterilized petri dishes, crosslinking under short UV light, spraying with aqueous suspensions of bacterial cells, air drying, and then applying agar media to promote bacterial growth. The plates were incubated for 24 h at 37 degrees C. The number of viable cells ranged from 17 to 0% growth. Immobilized VBT:QUAT copolymers are antiseptic surfaces that can be produced in an environmentally benign fashion.


Assuntos
Antibacterianos/síntese química , Materiais Revestidos Biocompatíveis/síntese química , Escherichia coli/crescimento & desenvolvimento , Polímeros/síntese química , Compostos de Amônio Quaternário/química , Timina/química , Antibacterianos/química , Materiais Revestidos Biocompatíveis/química , Teste de Materiais/métodos , Testes de Sensibilidade Microbiana/métodos , Fotoquímica/métodos , Polímeros/química
9.
Phys Rev Lett ; 84(6): 1120-3, 2000 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-11017458

RESUMO

Four different combinations of 9644Ru and 9640Zr nuclei, both as projectile and target, were investigated at the same bombarding energy of 400A MeV using a 4pi detector. The degree of isospin mixing between projectile and target nucleons is mapped across a large portion of the phase space using two different isospin-tracer observables, the number of measured protons and the tritium to 3He yield ratio. The experimental results show that the global equilibrium is not reached even in the most central collisions. Quantitative measures of stopping and mixing are extracted from the data. They are found to exhibit a quite strong sensitivity to the in-medium ( n,n) cross section used in microscopic transport calculations.

11.
Phys Rev Lett ; 102(18): 182501, 2009 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-19518864

RESUMO

The K0 meson production by pi(-) mesons of 1.15 GeV/c momentum on C, Al, Cu, Sn, and Pb nuclear targets was measured with the FOPI spectrometer at the Schwer-Ionen-Synchrotron accelerator of GSI. Inclusive production cross sections and the momentum distributions of K0 mesons are compared to scaled elementary production cross sections and to predictions of theoretical models describing the in-medium production of kaons. The data represent a new reference for those models, which are widely used for interpretation of the strangeness production in heavy-ion collisions. The presented results demonstrate the sensitivity of the kaon production to the reaction amplitudes inside nuclei and point to the existence of a repulsive KN potential of 20+/-5 MeV at normal nuclear matter density.

12.
Phys Rev Lett ; 98(25): 252001, 2007 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-17678015

RESUMO

We present particle spectra for charged hadrons pi(+/-), K(+/-), p, and p[over] from pp collisions at square root[s] = 200 GeV measured for the first time at forward rapidities (2.95 and 3.3). The kinematics of these measurements are skewed in a way that probes the small momentum fraction in one of the protons and large fractions in the other. Large proton to pion ratios are observed at values of transverse momentum that extend up to 4 GeV/c, where protons have momenta up to 35 GeV. Next-to-leading order perturbative QCD calculations describe the production of pions and kaons well at these rapidities, but fail to account for the large proton yields and small p[over]/p ratios.

13.
Phys Rev Lett ; 94(3): 032301, 2005 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-15698255

RESUMO

Charged-particle pseudorapidity densities are presented for the d + Au reaction at sqrt[s(NN)] = 200 GeV with -4.2 < or = eta < or = 4.2. The results, from the BRAHMS experiment at BNL Relativistic Heavy-Ion Collider, are shown for minimum-bias events and 0%-30%, 30%-60%, and 60%-80% centrality classes. Models incorporating both soft physics and hard, perturbative QCD-based scattering physics agree well with the experimental results. The data do not support predictions based on strong-coupling, semiclassical QCD. In the deuteron-fragmentation region the central 200 GeV data show behavior similar to full-overlap d+Au results at sqrt[s(NN)] = 19.4 GeV.

14.
Phys Rev Lett ; 94(16): 162301, 2005 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-15904216

RESUMO

We have measured rapidity densities dN/dy of pi+/- and K+/- over a broad rapidity range (-0.1 < y < 3.5) for central Au + Au collisions at square root(sNN) = 200 GeV. These data have significant implications for the chemistry and dynamics of the dense system that is initially created in the collisions. The full phase-space yields are 1660 +/- 15 +/- 133 (pi+), 1683 +/- 16 +/- 135 (pi-), 286 +/- 5 +/- 23 (K+), and 242 +/- 4 +/- 19 (K-). The systematics of the strange to nonstrange meson ratios are found to track the variation of the baryochemical potential with rapidity and energy. Landau-Carruthers hydrodynamics is found to describe the bulk transport of the pions in the longitudinal direction.

15.
Phys Rev Lett ; 92(7): 072303, 2004 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-14995843

RESUMO

Detailed studies of the azimuthal dependence of the mean fragment and flow energies in the Au+Au and Xe+CsI systems are reported as a function of incident energy and centrality. Comparisons between data and model calculations show that the flow energy values along different azimuthal directions could be viewed as snapshots of the fireball expansion with different exposure times. For the same number of participating nucleons more transversally elongated participant shapes from the heavier system produce less collective transverse energy. Good agreement with Boltzmann-Uehling-Uhlenbeck calculations is obtained for a soft nuclear equation of state.

16.
Phys Rev Lett ; 88(20): 202301, 2002 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-12005556

RESUMO

We present charged-particle multiplicities as a function of pseudorapidity and collision centrality for the 197Au+197Au reaction at square root[s(NN)] = 200 GeV. For the 5% most central events we obtain dN(ch)/deta/(eta = 0) = 625+/-55 and N(ch)/(-4.7< or =eta < or =4.7) = 4630 +/- 370, i.e., 14% and 21% increases, respectively, relative to square root[s(NN)] = 130 GeV collisions. Charged-particle production per pair of participant nucleons is found to increase from peripheral to central collisions around midrapidity. These results constrain current models of particle production at the highest RHIC energy.

17.
Phys Rev Lett ; 93(10): 102301, 2004 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-15447397

RESUMO

Transverse momentum spectra and rapidity densities, dN/dy, of protons, antiprotons, and net protons (p-p) from central (0%-5%) Au+Au collisions at square root of S(NN)=200 GeV were measured with the BRAHMS experiment within the rapidity range 0

18.
Phys Rev Lett ; 90(10): 102301, 2003 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-12688991

RESUMO

We present ratios of the numbers of charged antihadrons to hadrons (pions, kaons, and protons) in Au+Au collisions at sqrt[s(NN)]=200 GeV as a function of rapidity in the range y=0-3. While the ratios at midrapidity are approaching unity, the K(-)/K(+) and p;/p ratios decrease significantly at forward rapidities. An interpretation of the results within the statistical model indicates a reduction of the baryon chemical potential from mu(B) approximately 130 MeV at y=3 to mu(B) approximately 25 MeV at y=0.

19.
Phys Rev Lett ; 91(7): 072305, 2003 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-12935010

RESUMO

We present spectra of charged hadrons from Au+Au and d+Au collisions at sqrt[s(NN)]=200 GeV measured with the BRAHMS experiment at RHIC. The spectra for different collision centralities are compared to spectra from p+(-)p collisions at the same energy scaled by the number of binary collisions. The resulting ratios (nuclear modification factors) for central Au+Au collisions at eta=0 and eta=2.2 evidence a strong suppression in the high p(T) region (>2 GeV/c). In contrast, the d+Au nuclear modification factor (at eta=0) exhibits an enhancement of the high p(T) yields. These measurements indicate a high energy loss of the high p(T) particles in the medium created in the central Au+Au collisions. The lack of suppression in d+Au collisions makes it unlikely that initial state effects can explain the suppression in the central Au+Au collisions.

20.
Phys Rev Lett ; 93(24): 242303, 2004 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-15697798

RESUMO

We report on a study of the transverse momentum dependence of nuclear modification factors R(dAu) for charged hadrons produced in deuteron + gold collisions at sqrt[s(NN)]=200 GeV, as a function of collision centrality and of the pseudorapidity (eta=0, 1, 2.2, 3.2) of the produced hadrons. We find a significant and systematic decrease of R(dAu) with increasing rapidity. The midrapidity enhancement and the forward rapidity suppression are more pronounced in central collisions relative to peripheral collisions. These results are relevant to the study of the possible onset of gluon saturation at energies reached at BNL RHIC.

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