Tag: pubmed

Knee. 2022 Mar 19;35:157-163. doi: 10.1016/j.knee.2022.03.006. Online ahead of print.

ABSTRACT

BACKGROUND: Objects that manifest in several characteristic shapes, or morphotypes, are typically caused by some hidden variable. For example, the gender of a person influences the width of their pelvis. This is important when reconstructing natural shapes, e.g., in knee implant design. The aim of this study was to identify such morphotypes.

METHODS: This work investigated the shapes of roughly 1000 knee joints acquired from computed tomography, including the distal femur and proximal tibia. Two comprehensive feature sets were utilized to describe the bone shapes, one based on morphological measurements and the other on statistical shape model (SSM) weights. We normalized the data by size and performed a cluster analysis with different algorithms, namely k-means and high dimensional data clustering. The clusters were evaluated using several metrics.

RESULTS: The data showed a low tendency to form clusters. Only one of 12 experiments slightly exceeded the thresholds for actual clusters suggested by the literature. k-Means outperformed high dimensional data clustering in all cases.

CONCLUSION: After anisotropic normalization by size, which removes size and aspect ratio related differences, the data exhibited no morphotypes. This showed that there are no relevant hidden variables, e.g., gender, body type or ethnicity, which influence the shape of the knee joint. Instead, knee shape is highly individual. Investigating the three-dimensional shape, variations occur for a wide range of different shape parameters, not just for anterior-posterior and mediolateral size.

PMID:35316777 | DOI:10.1016/j.knee.2022.03.006

Eur J Obstet Gynecol Reprod Biol. 2022 Mar 11;272:156-159. doi: 10.1016/j.ejogrb.2022.03.007. Online ahead of print.

ABSTRACT

BACKGROUND: External cephalic version (ECV) is a technique used to reduce the incidence of cesarean deliveries due to malpresentation. Nitrous oxide is an inhaled analgesic that may be used for pain relief for women undergoing external cephalic version.

OBJECTIVE: To compare the conversion rate of non-cephalic to cephalic presentation in ECV with and without nitrous oxide.

STUDY DESIGN: A retrospective cohort analysis was performed including all singleton, term gestation ECVs between January 2016 and June 2017 at a single institution. Multivariable logistic regression was used to compare women who had ECV with nitrous oxide versus ECV without nitrous oxide. The primary outcome was successful rate of conversion to cephalic presentation and the secondary outcome was the rate of vaginal delivery.

RESULTS: During the study period, 167 women underwent ECV: 77 with nitrous oxide and 90 without nitrous oxide. Of the 77 women who used nitrous oxide, 25 (32.5%) were successful and 17 of these women delivered vaginally (68%). Of the women who underwent ECV without nitrous oxide, 29 (32.2%) successfully converted and 21 of these delivered vaginally (72%). After controlling for confounders, the use of nitrous oxide had no clinically or statistically significant difference on ECV success rates (OR 1.08, 95% CI 0.52-2.23).

CONCLUSION: Nitrous oxide does not seem to affect conversion rate to cephalic presentation in ECV. Further studies are needed to determine the impact of nitrous oxide on women’s decision to undergo ECV and on patient satisfaction and tolerability.

PMID:35316745 | DOI:10.1016/j.ejogrb.2022.03.007

Biosens Bioelectron. 2022 Mar 4;207:114133. doi: 10.1016/j.bios.2022.114133. Online ahead of print.

ABSTRACT

Lateral flow tests, commonly based on metal plasmonic nanoparticles, are rapid, robust, and low-cost. However, improvements in analytical sensitivity are required to allow detection of low-abundance biomarkers, for example detection of low antigen concentrations for earlier or asymptomatic diagnosis of infectious diseases. Efforts to improve sensitivity often require changes to the assay. Here, we developed optical methods to improve the sensitivity of absorption-based lateral flow tests, requiring no assay modifications to existing tests. We experimentally compared five different lock-in and subtraction-based methods, exploiting the narrow plasmonic peak of gold nanoparticles for background removal by imaging at different light wavelengths. A statistical framework and three fitting models were used to compare limits of detection, giving a 2.0-5.4-fold improvement. We then demonstrated the broad applicability of the method to an ultrasensitive assay, designing 530 nm composite nanoparticles to increase the particle volume, and therefore light absorption per particle, whilst retaining the plasmonic peak to allow background removal and without adding any assay steps. This multifaceted, modular approach gave a combined 58-fold improvement in the fundamental limit of detection using a biotin-avidin model over 50 nm gold nanoparticles with single-wavelength imaging. Applying to a sandwich assay for the detection of HIV capsid protein gave a limit of detection of 170 fM. Additionally, we developed an open-source software tool for performing the detection limit analysis used in this work.

PMID:35316759 | DOI:10.1016/j.bios.2022.114133

Healthc (Amst). 2022 Mar 19;10(2):100626. doi: 10.1016/j.hjdsi.2022.100626. Online ahead of print.

ABSTRACT

BACKGROUND: Responding to the shift toward value-based care, hospitals engaged in widespread experimentation of implementing transitional care (TC) strategies to improve patient experience and reduce unnecessary readmissions. However, which groups of these strategies are most strongly associated with better outcomes remains unknown.

METHODS: Using a retrospective longitudinal design, we collected hospitals’ TC strategy implementation data for 370 U S. hospitals and obtained claims data for 2.4 million Medicare fee-for-service beneficiaries hospitalized at them from 2009 to 2014. We applied estimated mixed-effects regression models controlling for patient, hospital, and community covariates to assess relationships between TC strategy groups and trends in hospitals’ 30-day hospital readmissions, with observation stay and mortality rates as secondary outcomes.

RESULTS: Hospitals’ adoption of TC groups was associated with higher readmission rates at baseline and larger readmission rate reductions compared to not adopting any of 5 TC groups. The TC group including timely information exchange across care settings, engaging patients and caregivers in education, and/or identifying and addressing patients’ transition needs was associated with the largest reductions. Hospitals not implementing any of the 5 TC groups had higher mortality rates and lower observation stay rates throughout the study period.

CONCLUSIONS: Our findings suggest that timely information sharing among providers across the care continuum and engaging patients in discharge planning and education may correspond with reduced readmissions.

IMPLICATIONS: Our research suggests that hospitals responded to shifts in policy by implementing a diversity of TC strategy combinations; it also provides guidance regarding which combinations of TC strategies corresponded with larger readmission reductions.

PMID:35316744 | DOI:10.1016/j.hjdsi.2022.100626

Neural Netw. 2022 Mar 10;150:194-212. doi: 10.1016/j.neunet.2022.03.006. Online ahead of print.

ABSTRACT

Direct multi-task twin support vector machine (DMTSVM) is an effective algorithm to deal with multi-task classification problems. However, the generated hyperplane may shift to outliers since the hinge loss is used in DMTSVM. Therefore, we propose an improved multi-task model RaMTTSVM based on ramp loss to handle noisy points more effectively. It could limit the maximal loss value distinctly and put definite restrictions on the influences of noises. But RaMTTSVM is non-convex which should be solved by CCCP, then a series of approximate convex problems need to be solved. So, it may be time-consuming. Motivated by the sparse solution of our RaMTTSVM, we further propose a safe acceleration rule MSA to accelerate the solving speed. Based on optimality conditions and convex optimization theory, MSA could delete a lot of inactive samples corresponding to 0 elements in dual solutions before solving the model. Then the computation speed can be accelerated by just solving reduced problems. The rule contains three different parts that correspond to different parameters and different iteration phases of CCCP. It can be used not only for the first approximate convex problem of CCCP but also for the successive problems during the iteration process. More importantly, our MSA is safe in the sense that the reduced problem can derive an identical optimal solution as the original problem, so the prediction accuracy will not be disturbed. Experimental results on one artificial dataset, ten Benchmark datasets, ten Image datasets and one real wine dataset confirm the generalization and acceleration ability of our proposed algorithm.

PMID:35316737 | DOI:10.1016/j.neunet.2022.03.006

Neural Netw. 2022 Mar 10;150:213-221. doi: 10.1016/j.neunet.2022.03.007. Online ahead of print.

ABSTRACT

This paper studies the Lyapunov stability of nonlinear systems and the synchronization of complex neural networks in the framework of event-triggered delayed impulsive control (ETDIC), where the effect of time delays in impulses is fully considered. Based on the Lyapunov-based event-triggered mechanism (ETM), some sufficient conditions are presented to avoid Zeno behavior and achieve globally asymptotical stability of the addressed system. In the framework of event-triggered impulse control (ETIC), control input is only generated at state-dependent triggered instants and there is no any control input during two consecutive triggered impulse instants, which can greatly reduce resource consumption and control waste. The contributions of this paper can be summarized as follows: Firstly, compared with the classical ETIC, our results not only provide the well-designed ETM to determine the impulse time sequence, but also fully extract the information of time delays in impulses and integrate it into the dynamic analysis of the system. Secondly, it is shown that the time delays in impulses in our results exhibit positive effects, that is, it may contribute to stabilizing a system and achieve better performance. Thirdly, as an application of ETDIC strategies, we apply the proposed theoretical results to synchronization problem of complex neural networks. Some sufficient conditions to ensure the synchronization of complex neural networks are presented, where the information of time delays in impulses is fully fetched in these conditions. Finally, two numerical examples are provided to show the effectiveness and validity of the theoretical results.

PMID:35316738 | DOI:10.1016/j.neunet.2022.03.007

Theriogenology. 2022 Mar 13;184:124-131. doi: 10.1016/j.theriogenology.2022.03.001. Online ahead of print.

ABSTRACT

The aim of this retrospective study was to compare simple linear regression and mixed linear regression on data grouped by breed or maternal weight group. The comparison was done to find the most accurate model for predicting day of parturition in pregnant bitches in clinical practice. The retrospective data consisted of fetal biparietal diameter determined by ultrasonography and day of parturition for all included bitches. The study population was divided into five maternal weight groups (miniature (≤5 kg), small (>5 to 10 kg), medium (>10 to 25 kg), large (>25 to 40 kg), and giant (>40 kg)) with three breeds in each group with 26 miniature-breed bitches, 13 small-breed bitches, 19 medium-breed bitches, 22 large-breed bitches, and 20 giant-breed bitches. The data was used to develop models to determine the number of days before parturition based on fetal biparietal diameter. A statistically significant effect was seen for grouping by maternal weight group (p<0.0001) and by breed (p=0.0057). Breed-specific models were derived and compared to each other within the same maternal weight group. Statistically significant differences between some miniature-breed and small-breed bitches were found using mixed linear regression analysis. The accuracies of all models were given as number of births within ±1 and ±2 days of estimated day of parturition and compared to an acceptable limit of 80% at ±2 days. All breeds and maternal weight groups except Dogue de Bordeaux and giant-breed bitches met the limit. Poor accuracies were seen when applying data from each breed to the maternal weight grouped model. Simple linear regression analyses were compared to mixed linear regression analyses. The simple linear regression analyses obtained the best accuracies for most of the breeds which is most likely to be caused by overestimation. Comparison of Chihuahua and German Shepherd to other studies showed similar accuracies between the highest reported and the two linear models. We recommend the use of breed-specific models based on mixed linear regression analysis in clinical practice. Further research is needed to analyze the differences between the two linear models and to confirm the tendency of more accurate predictions of day of parturition for medium-breed, large-breed, and giant-breed bitches when using breed-specific models.

PMID:35316731 | DOI:10.1016/j.theriogenology.2022.03.001

Eur J Radiol. 2022 Mar 17;150:110261. doi: 10.1016/j.ejrad.2022.110261. Online ahead of print.

ABSTRACT

PURPOSE: To primarily evaluate the diagnostic performance of the monoexponential and intravoxel incoherent motion (IVIM) diffusion weighted imaging (DWI) models for differentiating between nonhypervascular pancreatic neuroendocrine tumors (PNETs) and pancreatic ductal adenocarcinomas (PDACs).

METHODS: 63 patients with PNETs (35 nonhypervascular PNETs and 28 hypervascular PNETs) and 164 patients with PDACs were retrospectively enrolled in the study and underwent multiple b-value DWI. Intraobserver and interobserver reliabilities of DWI parameters were assessed by using the intraclass correlation coefficient (ICC). The parameters of apparent diffusion coefficient (ADC), true diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f) of nonhypervascular PNETs were compared with PDACs and hypervascular PNETs using the independent sample t test or the Mann-Whitney U test. The diagnostic performance was evaluated using receiver operating characteristic (ROC) analysis.

RESULTS: All DWI parameters values showed good to excellent intra- and interobserver agreements (ICC = 0.743-0.873). Nonhypervascular PNETs had significantly lower ADC and D, but significantly higher f than PDACs (P = 0.005, P < 0.001 and P < 0.001, respectively). ADC, D and f of nonhypervascular PNETs were lower than hypervascular PNETs (P = 0.001, <0.001 and 0.093, respectively). D* of nonhypervascular PNETs showed no statistically significant differences with PDACs and hypervascular PNETs (P = 0.809 and 0.420). D showed a higher area under the curve (AUC), followed by ADC and f (AUC = 0.885, 0.665 and 0.740, respectively) in differentiating nonhypervascular PNETs from PDACs.

CONCLUSION: Monoexponential and IVIM diffusion models are valuable to differentiate nonhypervascular PNETs from PDACs. D showed better performance than f and ADC.

PMID:35316674 | DOI:10.1016/j.ejrad.2022.110261

Forensic Sci Int Genet. 2022 Mar 16;58:102689. doi: 10.1016/j.fsigen.2022.102689. Online ahead of print.

ABSTRACT

In forensic applications, there is an increasing demand for the analysis of DNA profiles arising from missing person identification (MPI) cases. A specific DNA profile may originate from a single source or more than one contributor (i.e., a DNA mixture). When direct references are not available, indirect relative references can be used to identify missing persons by kinship analysis. As a novel kind of multiallelic marker, microhaplotypes have proven promising for relatedness determination and mixture deconvolution. Herein, we developed a large panel of 185 microhaplotype markers and demonstrated its application in different scenarios of relationship inference through a simulation study and real pedigree analysis, combined with probabilistic genotyping models for data interpretation. Based on single-source profiles, it was shown that the present microhaplotype panel was sufficient for pairwise close relative testing (parent/child, full-sibling and 2nd-degree relative). For more distant relatives (3rd-degree relatives), there was a clear improvement when data from one well-chosen extra relative were available. We further sought to evaluate the theoretical systematic effectiveness and actual performance of microhaplotype markers in identifying the contribution of a missing pedigree member to a two-person mixture (as a minor donor). It was observed that 100% correct assignments were made in the balanced mixtures (with no dropout) when referenced to close relatives. When the mixture profiles suffered from dropout, incorrect assignments of minor donors were markedly associated with relatedness and the dropout level. Meanwhile, the studied scenarios generally exhibited zero or very low false-positive rates, indicating a low probability of incorrectly assigning an unrelated contributor as a close relative of the reference. Our results indicate that microhaplotype data can be reliably interpreted for identifying missing persons through kinship analysis based on DNA profiles of single-source samples or two-person mixtures. Furthermore, this study could be extended to more complex scenarios, such as determining the relatedness of contributors in (or among) mixed DNA profiles, if combined with different statistical frameworks.

PMID:35316721 | DOI:10.1016/j.fsigen.2022.102689

Asian J Psychiatr. 2022 Mar 14;71:103086. doi: 10.1016/j.ajp.2022.103086. Online ahead of print.

ABSTRACT

OBJECTIVE: To examine whether thyroid function in the normal range is associated with recurrence of depressive or mania in bipolar disorder patients.

METHODS: 104 patients with bipolar disorder in maintenance therapy phase were assigned randomly to mood stabilizer combined with antidepressant group or mood stabilizer group. There were 52 patients in both groups respectively. Clinical symptoms were assessed at baseline, 3rd month, 6th month, 9th month, and 12th month using HAMD-17 and YMRS. Blood samples were analyzed for thyroid function.

RESULTS: There was no statistically significant difference of recurrence rate of depressive episode and mania episode at the end of the 12-months between mood stabilizer combined with antidepressant group and mood stabilizer group. There was significant relation of baseline TT4 (P = 0.020, HR = 0.948), FT3 (P = 0.035, HR = 2.055), and FT4 (P = 0.047, OR=0.769) with the recurrence of depressive episode in mood stabilizer group. The area under curve (AUC) of TT4, FT3, FT4 were 0.685, 0.613, 0.544, respectively. There was significant relation of baseline FT3 (P = 0.044，HR = 4.493) with the recurrence of mania episode for mood stabilizer combined with antidepressants group. The AUC of FT3 was 0.806.

CONCLUSION: Low level of TT4, FT4 and high level of FT3 within normal-range were related with the recurrence of depressive episode in the maintenance treatment with mood stabilizer of bipolar disorder. High level of FT3 within normal-range were related with recurrence of mania when mood stabilizer combined with antidepressants were used in the maintenance treatment of bipolar disorder.

PMID:35316669 | DOI:10.1016/j.ajp.2022.103086