Tag: pubmed

Ann Nucl Med. 2021 Mar 26. doi: 10.1007/s12149-021-01608-5. Online ahead of print.

ABSTRACT

AIM: To evaluate the use of digital ¹⁸F-FDG PET/CT with small-voxels reconstruction for detecting in-transit metastases in melanoma patients with primary lesion located on the upper or lower limbs, in comparison with standard reconstruction and European Association of Nuclear Medicine Research limited (EARL)-compliant reconstruction mimicking former generation PET systems.

METHODS: Forty-six PET examinations acquired in list mode on a Vereos digital PET/CT system were reconstructed with (1) the standard reconstruction [2 iterations, 10 subsets (2i10s), point-spread function (PSF) modelling and time-of-flight enabled, no post-filtering and voxel size of 2 mm], (2) a small-voxel reconstruction using 1 mm voxels otherwise using the same parameters, (3) an EARL-compliant reconstruction mimicking a former generation system. Comparison of results across these reconstructions was made for a blind randomized review using a 3-point scale for the presence of in-transit metastases and image quality as well as for tumour-to-background (T/B) ratios and noise level in reference organs.

RESULTS: Seven of the thirty-two EARL-compliant images classified as negative moved to positive on 1mm_PSF images, and 5 of the 6 EARL-compliant images classified as indeterminate moved to positive on 1mm_PSF images (P = 0.01). Amongst a total of 20 PET examinations classified as positive using the 1mm_PSF reconstruction, fifteen were considered true positive, five false positive results occurred. Twenty-four patients with 1 mm PSF images were classified as negative, none of those under active surveillance experienced in-transit metastases during the 17 months following their PET examination. The positive likelihood ratio for the 1 mm reconstruction was much higher than that observed for EARL-compliant images (14.7 vs 7.82). Importantly, negative likelihood ratios for the 1 mm and 1mm_PSF reconstruction were almost perfect. Compared to EARL-compliant data, T/B ratios extracted from the 1mm_PSF showed a 2.84-fold increase (P < 0.001). A similar pattern of statistically significant increase was observed for noise level in organs of reference. Image quality for the torso was found to be significantly lower for 1mm_PSF reconstruction (P = 0.03). Image quality for the limbs was found to be better for 1mm_PSF (P < 0.001).

CONCLUSION: Digital PET with small-voxel reconstruction brings an additional value for the detection of in-transit metastases by reducing the number of indeterminate findings and making up for falsely negative scans using former generation PET systems. An acquisition encompassing lower or upper limbs as appropriate should be performed.

PMID:33770374 | DOI:10.1007/s12149-021-01608-5

Mol Biol Rep. 2021 Mar 26. doi: 10.1007/s11033-021-06292-2. Online ahead of print.

ABSTRACT

Venustaconcha ellipsiformis (Unionidae) is a freshwater mussel species inhabiting small to medium streams of the Midwestern United States; however, its occurrence is rather sporadic and populations are often isolated. Due to anthropogenic habitat degradation and water pollution, this species is designated as some sort of conservation status in many states. To prioritize conservation strategies, highly variable genetic markers are necessary to assess population genetic structure and potential genetic erosion of V. ellipsiformis. Using whole genome sequence data, we developed and characterized microsatellite markers for V. ellipsiformis. Among 23 tetranucleotide loci tested, 14 loci were consistently amplified and showed polymorphism. Analyses performed on three populations in the upper Mississippi River basin showed that the number of alleles per locus ranged from 2 to 11 and the observed heterozygosity varied from 0.15 to 0.75. Based on genotypic and allelic rarefaction curves, these loci had adequate statistical power to genetically discriminate between individuals and the sample size was large enough to capture most alleles available in the populations at most loci. Finally, cross-species screening of the loci successfully amplified and showed polymorphism in six species in the tribe Lampsilini. The microsatellite loci developed in this study provide a valuable addition to extant genetic markers for freshwater mussels and can be useful to provide high-level resolution of population genetic parameters for V. ellipsiformis. Such information will be of great value for resource managers developing and prioritizing conservation strategies for imperiled mussel species.

PMID:33770294 | DOI:10.1007/s11033-021-06292-2

Environ Geochem Health. 2021 Mar 26. doi: 10.1007/s10653-021-00882-6. Online ahead of print.

ABSTRACT

In arid and semiarid regions, groundwater is required for the drinking, agriculture, and industrial activities due to scarcity of surface water. Groundwater contaminated with high concentrations of fluoride and nitrate can severely affect human health in these regions. Twenty-eight groundwater samples from rural habitations of Jhunjhunu district, Rajasthan, India, were collected in March 2018 and subjected to analysis for water quality parameters. Fluoride and nitrate concentrations in groundwater varied from 0 to 5.74 mg/L and 10.22-519.64 mg/L, respectively. Nitrate content of about 86% samples and fluoride content of about 54% exceeded the permissible limit of Bureau of Indian Standards (IS:10,500) as well as World Health Organization standards. All groundwater samples belonged to poor to unfit drinking water quality index. Principle component analysis elucidates the anthropogenic contribution to high nitrate concentrations observed in this area. Noncarcinogenic human health risk evaluated from high nitrate and fluoride in drinking water for children, men, and women points to the fact that noncarcinogenic risk is exceeding the allowable limit to human health. The predominating hydrochemical facies in the area is Na⁺-HCO₃^–-Cl^– followed by Na⁺-Mg²⁺-HCO₃^–-Cl^–. The Gibbs plot and bivariate ionic cross-plots suggest the noncarbonate weathering (rock dominance), evaporation dominance, and ion exchange process to be the predominating geochemical mechanisms governing the evolution of groundwater hydrogeochemistry. Giggenbach diagram shows the immature character, i.e., incomplete equilibration of the groundwater.

PMID:33770299 | DOI:10.1007/s10653-021-00882-6

Biomech Model Mechanobiol. 2021 Mar 26. doi: 10.1007/s10237-021-01444-6. Online ahead of print.

ABSTRACT

This paper aims to investigate detailed mechanical interactions between the pulmonary haemodynamics and left heart function in pathophysiological situations (e.g. atrial fibrillation and acute mitral regurgitation). This is achieved by developing a complex computational framework for a coupled pulmonary circulation, left atrium and mitral valve model. The left atrium and mitral valve are modelled with physiologically realistic three-dimensional geometries, fibre-reinforced hyperelastic materials and fluid-structure interaction, and the pulmonary vessels are modelled as one-dimensional network ended with structured trees, with specified vessel geometries and wall material properties. This new coupled model reveals some interesting results which could be of diagnostic values. For example, the wave propagation through the pulmonary vasculature can lead to different arrival times for the second systolic flow wave (S2 wave) among the pulmonary veins, forming vortex rings inside the left atrium. In the case of acute mitral regurgitation, the left atrium experiences an increased energy dissipation and pressure elevation. The pulmonary veins can experience increased wave intensities, reversal flow during systole and increased early-diastolic flow wave (D wave), which in turn causes an additional flow wave across the mitral valve (L wave), as well as a reversal flow at the left atrial appendage orifice. In the case of atrial fibrillation, we show that the loss of active contraction is associated with a slower flow inside the left atrial appendage and disappearances of the late-diastole atrial reversal wave (AR wave) and the first systolic wave (S1 wave) in pulmonary veins. The haemodynamic changes along the pulmonary vessel trees on different scales from microscopic vessels to the main pulmonary artery can all be captured in this model. The work promises a potential in quantifying disease progression and medical treatments of various pulmonary diseases such as the pulmonary hypertension due to a left heart dysfunction.

PMID:33770307 | DOI:10.1007/s10237-021-01444-6

Psychometrika. 2021 Mar 26. doi: 10.1007/s11336-021-09755-4. Online ahead of print.

ABSTRACT

The likelihood ratio test is widely used in exploratory factor analysis to assess the model fit and determine the number of latent factors. Despite its popularity and clear statistical rationale, researchers have found that when the dimension of the response data is large compared to the sample size, the classical Chi-square approximation of the likelihood ratio test statistic often fails. Theoretically, it has been an open problem when such a phenomenon happens as the dimension of data increases; practically, the effect of high dimensionality is less examined in exploratory factor analysis, and there lacks a clear statistical guideline on the validity of the conventional Chi-square approximation. To address this problem, we investigate the failure of the Chi-square approximation of the likelihood ratio test in high-dimensional exploratory factor analysis and derive the necessary and sufficient condition to ensure the validity of the Chi-square approximation. The results yield simple quantitative guidelines to check in practice and would also provide useful statistical insights into the practice of exploratory factor analysis.

PMID:33770318 | DOI:10.1007/s11336-021-09755-4

Support Care Cancer. 2021 Mar 26. doi: 10.1007/s00520-021-06166-0. Online ahead of print.

ABSTRACT

OBJECTIVE: This study aims to evaluate the treatment effect of a mindfulness-based intervention for Chinese breast cancer patients across outcome domains, including symptom-related, psychosocial, and quality of life outcomes.

METHODS: Following the Cochrane Systematic Review guideline, we searched across five electronic databases, reference lists of eligible studies, professional websites, and major academic journals in Chinese. Publication bias was assessed using funnel plot and Vevea and Woods sensitivity analysis, and risk of bias was evaluated using the revised Cochrane risk of bias tool for randomized trials and risk of bias in non-randomized studies of interventions. A meta-analysis of Hedges’ g was conducted using meta-regression with robust variance estimation.

RESULTS: Final analysis included a total of 45 controlled trials containing 286 effect size estimates. Across outcome domains, studies reported an overall large and statistically significant treatment effect, d = 0.921, 95% CI (0.805, 1.040), p < 0.001. Subgroup analyses of specific domains of outcome reported overall significant treatment effects for (1) symptom-related outcomes, d = 0.885, 95% CI (0.657, 1.110), p < 0.001; (2) psychosocial wellness outcomes, d = 0.984, 95% CI (0.879, 1.090), p < 0.001; and (3) quality of life, d = 0.990, 95% CI (0.776, 1.200), p < 0.001. Moderator analysis did not identify any significant moderator.

CONCLUSION: Chinese literature reported an overall statistically significant and large treatment effect of a mindfulness-based intervention for breast cancer patients in China. Except for physical symptom outcomes, e.g., nausea/vomiting and pain, a mindfulness-based intervention was effective across outcome domains among Chinese breast cancer patients.

PMID:33770259 | DOI:10.1007/s00520-021-06166-0

Graefes Arch Clin Exp Ophthalmol. 2021 Mar 26. doi: 10.1007/s00417-021-05165-5. Online ahead of print.

ABSTRACT

PURPOSE: To assess the long-term outcomes of transcanalicular laser dacryocystorhinostomy in cases of primary acquired nasolacrimal duct obstruction (PANDO).

METHODS: Retrospective interventional case series was performed on all patients diagnosed with PANDO and who underwent a primary transcanalicular laser dacryocystorhinostomy from Jan 2014 to June 2016. The procedure was performed using 980 nm diode laser. All the patients additionally underwent intraoperative adjunctive procedures: mitomycin C application and silicone intubation. Patients were followed for up to 3 years after surgery. Anatomical success was defined as patent ostium on irrigation, and functional success was defined as resolution of epiphora. The parameters studied include patient demographics, clinical presentation, type of anesthesia, duration of surgery, laser energy delivered, complications, and anatomical and functional success. The variables influencing the outcomes were assessed. Statistical analysis was performed using the package Statistica (version 10.0, Statsoft, Poland).

RESULTS: A total number of 205 patients were assessed. Of these, 73.17% (150/205) were females. The mean age of patients was 62.92 years. The mean laser energy used was 1060.09 J, and the mean operating time was 22.33 min. Approximately, 95% and 68% of the patients completed 1 year and 3 years of follow-up, respectively. The anatomical and functional success rates dropped significantly beyond the 3 months and 6 months postoperative period and maintained the lower success rates beyond 1-year follow-up for up to 3 years. The anatomical and functional success at the end of 3-year follow-up was 56.12% and 33.81%, respectively. The functional success was not affected by gender (P = 0.132), age (P = 0.956), laser energy (P = 0.626), or duration of the surgery (P = 0.906). However, the intraoperative pain scale was influenced by the laser energy (P < 0.001) and the duration of the surgery (P < 0.001).

CONCLUSION: The anatomical and functional outcomes of primary transcanalicular laser dacryocystorhinostomy are suboptimal and not encouraging in the long term.

PMID:33770269 | DOI:10.1007/s00417-021-05165-5

Pediatr Nephrol. 2021 Mar 26. doi: 10.1007/s00467-021-04999-9. Online ahead of print.

ABSTRACT

BACKGROUND: Acute kidney Injury (AKI) in children undergoing cardiac surgery (CS) is strongly associated with hospital morbidity. Post-discharge CS AKI outcomes are less clear. We evaluated associations between AKI and post-discharge (a) healthcare utilization, (b) chronic kidney disease (CKD) or hypertension and (c) mortality.

METHODS: This is a retrospective two-centre cohort study of children surviving to hospital discharge after CS. Primary exposures were post-operative ≥Stage 1 AKI and ≥Stage 2 AKI defined by Kidney Disease Impoving Global Outcomes. Association of AKI with time to outcomes was determined using multivariable Cox-Proportional Hazards analysis.

RESULTS: Of 350 participants included (age 3.1 (4.5) years), 180 [51.4%] developed AKI and 60 [17.1%] developed ≥Stage 2 AKI. Twenty-eight (9%) participants developed CKD or hypertension (composite outcome), and 17 (5%) died within 5 years of discharge. Post-operative ≥Stage 1 and ≥Stage 2 AKI were not associated with post-discharge hospitalizations, emergency room (ER) visits, physician visits or CKD or hypertension in adjusted analyses. A trend was observed between ≥Stage 2 AKI and mortality but was not statistically significant. In unadjusted stratified analyses, AKI was associated with post-discharge hospitalizations in children with RACHS-1 score ≥3, complex chronic disease classification and children living in urban areas.

CONCLUSIONS: Post-CS AKI is not associated with post-discharge healthcare utilization, death and CKD or hypertension, though it may be associated with healthcare utilization in more complex paediatric CS children. Studies should aim to better understand post-CS healthcare utilization patterns and non-AKI risk factors for CKD, hypertension and mortality, to reduce adverse long-term outcomes after CS.

PMID:33770283 | DOI:10.1007/s00467-021-04999-9

J Food Prot. 2021 Mar 26. doi: 10.4315/JFP-20-431. Online ahead of print.

ABSTRACT

Spoilage of HTST- (high-temperature, short-time) and vat- pasteurized fluid milk due to introduction of Gram-negative bacteria post-pasteurization remains a challenge for the dairy industry. While processing facility level practices (e.g., sanitation practices) are known to impact the frequency of post-pasteurization contamination (PPC), the relative importance of different practices is not well defined, affecting the ability of facilities to select intervention targets that reduce PPC and provide the greatest return on investment. Thus, the goal of this study was to use an existing longitudinal dataset of bacterial spoilage indicators obtained for pasteurized fluid milk samples collected from 23 processing facilities between July 2015 and November 2017 (with 3 to 5 samplings per facility) and data from a survey on fluid milk quality management practices, to identify factors associated with PPC and rank their relative importance, using two separate approaches: (i) multimodel inference and (ii) conditional random forest. Data pre-processing for multimodel inference analysis showed (i) nearly all factors were significantly associated with PPC when assessed individually using univariable logistic regression and (ii) numerous pairs of factors were strongly associated with each other (Cramer’s V ³0.80). Multimodel inference and conditional random forest analyses identified similar drivers associated with PPC; factors identified as most important based on these analyses included cleaning and sanitation practices, activities related to good manufacturing practices, container type (which is a proxy for different filling equipment), in-house finished product testing, and designation of a quality department, indicating potential targets for reducing PPC. In addition, this study illustrates how machine learning approaches can be used with highly correlated and unbalanced data, as typical for food safety and quality, to facilitate improved data analyses and decision-making.

PMID:33770185 | DOI:10.4315/JFP-20-431

Abdom Radiol (NY). 2021 Mar 26. doi: 10.1007/s00261-021-03046-3. Online ahead of print.

ABSTRACT

BACKGROUND: Bowel preparation before multiparametric MRI (mpMRI) of the prostate is performed widely, despite contradictory or no evidence for efficacy.

PURPOSE: To investigate the value of hyoscine N-butylbromide (HBB), microenema (ME) and ‘dietary restrictions’ (DR) for artifact reduction and image quality (IQ) in mpMRI of the prostate.

STUDY TYPE: Retrospective.

POPULATION: Between 10/2018 and 02/2020 treatment-naïve men (median age, 64.9; range 39.8-87.3) who underwent mpMRI of the prostate were included. The total patient sample comprised of n = 180 patients, who received either HBB, ME, were instructed to adhere to DR, or received a combination of those measures prior to the MR scan.

FIELD STRENGTH/SEQUENCE: T2-weighted imaging (T2w), diffusion-weighted imaging (DWI), and dynamic contrast-enhanced MRI (DCE-MRI) scanned on two 3T systems.

ASSESSMENT: A radiologist specialized in urogenital imaging (R1) and a senior radiology resident (R2) visually assessed IQ parameters on transversal T2w, DWI and ADC maps on a 5-point Likert-like scale.

STATISTICAL TESTS: Group comparison between IQ parameters was performed on reader level using Kruskal-Wallis and Mann-Whitney U tests. Binary univariate logistic regression analysis was used to assess independent predictors of IQ. Interrater agreement was assessed using Intraclass Correlation Coefficient (ICC).

RESULTS: ‘DWI geometric distortion’ was significantly more pronounced in the HBB+/ME-/DR- (R1, 3.6 and R2, 4.0) as compared to the HBB-/ME+/DR- (R1, 4.2 and R2, 4.6) and HBB+/ME+/DR- (R1, 4.3 and R2, 4.7) cohort, respectively. Parameters ‘DWI IQ’ and ‘Whole MRI IQ’ were rated similarly by both readers. ME was a significant independent predictor of ‘good IQ’ for the whole MRI for R1 [b = 1.09, OR 2.98 (95% CI 1.29, 6.87)] and R2 [b = 1.01, OR 2.73 (95% CI 1.24, 6.04)], respectively.

DATA CONCLUSION: ME seems to significantly improve image quality of DWI and the whole mpMRI image set of the prostate. HBB and DR did not have any benefit.

PMID:33770222 | DOI:10.1007/s00261-021-03046-3