Category: Statistics

Comput Med Imaging Graph. 2021 Mar 31;90:101911. doi: 10.1016/j.compmedimag.2021.101911. Online ahead of print.

ABSTRACT

Appropriate treatment of bladder cancer (BC) is widely based on accurate and early BC staging. In this paper, a multiparametric computer-aided diagnostic (MP-CAD) system is developed to differentiate between BC staging, especially T1 and T2 stages, using T2-weighted (T2W) magnetic resonance imaging (MRI) and diffusion-weighted (DW) MRI. Our framework starts with the segmentation of the bladder wall (BW) and localization of the whole BC volume (V_t) and its extent inside the wall (V_w). Our segmentation framework is based on a fully connected convolution neural network (CNN) and utilized an adaptive shape model followed by estimating a set of functional, texture, and morphological features. The functional features are derived from the cumulative distribution function (CDF) of the apparent diffusion coefficient. Texture features are radiomic features estimated from T2W-MRI, and morphological features are used to describe the tumors’ geometric. Due to the significant texture difference between the wall and bladder lumen cells, V_t is parcelled into a set of nested equidistance surfaces (i.e., iso-surfaces). Finally, features are estimated for individual iso-surfaces, which are then augmented and used to train and test machine learning (ML) classifier based on neural networks. The system has been evaluated using 42 data sets, and a leave-one-subject-out approach is employed. The overall accuracy, sensitivity, specificity, and area under the receiver operating characteristics (ROC) curve (AUC) are 95.24%, 95.24%, 95.24%, and 0.9864, respectively. The advantage of fusion multiparametric iso-features is highlighted by comparing the diagnostic accuracy of individual MRI modality, which is confirmed by the ROC analysis. Moreover, the accuracy of our pipeline is compared against other statistical ML classifiers (i.e., random forest (RF) and support vector machine (SVM)). Our CAD system is also compared with other techniques (e.g., end-to-end convolution neural networks (i.e., ResNet50).

PMID:33848756 | DOI:10.1016/j.compmedimag.2021.101911

Surg Oncol. 2021 Apr 2;37:101554. doi: 10.1016/j.suronc.2021.101554. Online ahead of print.

ABSTRACT

INTRODUCTION: The rate of adrenal disease diagnosed is progressively increasing due to the diagnostic tools improvement. We analysed patients that underwent to adrenalectomy in our centre for different adrenal pathologies and we tried to established guidelines for the surgical therapy.

METHODS: Demographic and clinical data were prospectively entered in a computerized endocrine surgery registry for all patients who underwent surgery for adrenal lesions at our institution over a 35-year period and statistical analyses was performed.

RESULTS: Between 1986 and 2020, 502 patients underwent adrenalectomy: open adrenalectomy (OA) was performed in 104 patients (28,6%), laparoscopic adrenalectomy (LA) in 398 patients (71,4%). The rate of conversion to OA was 5,9% (21 patients). The mean operating time in laparoscopic approach was 84.3 min (range 40-180) while in open approach was 121.9 min (40-210). The average length of stay (LOS) for LA was 3.6 days, while for OA was 7.4 days. The time to return to normal activity for LA was 21 days while for OA was 37 days.

CONCLUSIONS: The progressive increase in the number of adrenalectomies performed is due more to a better understanding of adrenal disease than to the availability of minimally invasive techniques. The choice of a laparoscopic approach should depend on the surgeon’s experience, regardless the dimension of the lesion. Considering our long experience, we suggest OA for lesion of more of 6 cm, for malignant lesion with a diameter higher than 3 cm or with a pre-operatory evidence of invasion of the surrounding tissue.

PMID:33848760 | DOI:10.1016/j.suronc.2021.101554

J Anim Physiol Anim Nutr (Berl). 2021 Apr 13. doi: 10.1111/jpn.13545. Online ahead of print.

ABSTRACT

This study was conducted to investigate the effects of dietary rice brewer waste (RBW) on growth performance, nutrient utilization and nitrogen balance in growing rabbits. Thirty growing rabbits (758 ± 25.7 g initial body weight) were randomly assigned to control and four treatment groups (containing RBW) in a completely randomized design with six rabbits per group. The study lasted 6 weeks for measurements of feed intake and growth performance followed by a five-day metabolic trial to determine nutrient digestibility and nitrogen balance. The five diets contained RBW at 0% RBW (control group), unsterilized RBW at 10% and 20% and sterilized RBW at 10% and 20% in the concentrates. The average daily body weight gain (ADG) in the 20% unsterilized RBW group was higher (p < 0.01) than the control group. No statistically significant difference (p = 0.089) of ADG was observed for the control vs. the sterilized groups, but the overall ADG was better (p = 0.044) in the unsterilized RBW groups than the sterilized RBW groups. The daily dry matter intake in unsterilized and sterilized RBW groups was higher (p < 0.01) than the control group. However, no difference (p = 0.22) was found between the unsterilized and sterilized RBW. The feed conversion ratio (FCR) was lower for the unsterilized RBW groups vs. the control group (p = 0.041), but there was no difference of FCR in the control vs. sterilized RBW groups (p = 0.37) and the unsterilized RBW groups vs. unsterilized RBW groups (p = 0.14). The digestibility of organic matter, crude protein and crude fibre was greater (p < 0.01) in the unsterilized and sterilized RBW groups than the control group. The nitrogen balance and efficiency of nitrogen utilization were also higher in the unsterilized and sterilized RBW groups than the control group (p < 0.01). The study showed that the dietary RBW could improve growth performance and nutrient utilization in growing rabbits with superior responses for the unsterilized RBW.

PMID:33848037 | DOI:10.1111/jpn.13545

Int J Ment Health Nurs. 2021 Apr 13. doi: 10.1111/inm.12867. Online ahead of print.

ABSTRACT

The COVID-19 outbreak negatively impacted the mental health and emotions of many individuals. The study presented here explores the mental health and emotion regulation experienced by undergraduate nursing students in China during the pandemic. Potential risk factors related to negative mental health symptoms were identified in this study. An online cross-sectional study including 342 respondents was performed from March 6, 2020, to April 1, 2020, at a University in China. A Generalized Anxiety Disorder-7 (GAD-7), Patient Health Questionnaire-9 (PHQ-9), and Emotion Regulation Questionnaire (ERQ) were used to evaluate mental health and emotions. The statistical analysis was performed using the Statistical Package for Social Sciences (SPSS) version 22. The prevalence of anxiety, depression, or comorbid anxiety and depression were 55.0%, 56.4%, and 31.6%, respectively. The mean score of cognitive reappraisal and expressive suppression was 29.36 ± 8.00 and 15.55 ± 5.14. Lower scores for cognitive reappraisal and higher scores for expressive suppression were susceptible to symptoms of anxiety, depression, or comorbid anxiety and depression. Issues with mental health occurred in nursing students during the COVID-19 pandemic. Findings from this study provide a better understanding of the association between mental health and emotion regulation, which will help direct psychological intervention that relieves these issues during the pandemic.

PMID:33848056 | DOI:10.1111/inm.12867

Adv Exp Med Biol. 2021;1256:191-200. doi: 10.1007/978-3-030-66014-7_7.

ABSTRACT

Age-related macular degeneration (AMD) is a multifactorial neurodegenerative disease, which is a leading cause of vision loss among the elderly in the developed countries. As one of the most successful examples of genome-wide association study (GWAS), a large number of genetic studies have been conducted to explore the genetic basis for AMD and its progression, of which over 30 loci were identified and confirmed. In this chapter, we review the recent development and findings of GWAS for AMD risk and progression. Then, we present emerging methods and models for predicting AMD development or its progression using large-scale genetic data. Finally, we discuss a set of novel statistical and analytical methods that were recently developed to tackle the challenges such as analyzing bilateral correlated eye-level outcomes that are subject to censoring with high-dimensional genetic data. Future directions for analytical studies of AMD genetics are also proposed.

PMID:33848002 | DOI:10.1007/978-3-030-66014-7_7

Int J Dermatol. 2021 Apr 13. doi: 10.1111/ijd.15586. Online ahead of print.

ABSTRACT

BACKGROUND: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are potentially fatal adverse drug reactions. The characteristics of these diseases are changing with the use of novel drugs, posing new challenges to doctors. We aimed to review recent SJS/TEN cases in order to assist general practitioners with timely diagnosis and correct management.

METHODS: We conducted a retrospective chart review of SJS/TEN patients in a referral center in Taiwan from 2009 to 2019. We included 24 patients’ charts and analyzed demographic data, medication histories, clinical courses, human leukocyte antigen (HLA) alleles, and long-term complications.

RESULTS: The average age was 63.4 years, and the average toxic epidermal necrolysis-specific severity of illness score was 1.9. The most common culprit drug was carbamazepine (33.3%), followed by antibiotics (12.5%) and nonsteroidal anti-inflammatory drugs (8.3%). Two cases were caused by immune checkpoint inhibitors, and one of them had a long latency of 210 days. Three out of the four patients carrying HLA-B*15:02 had carbamazepine-induced SJS/TEN. All patients were treated with systemic corticosteroids in the acute stage of the diseases. The length of in-hospital stay did not correlate with the average daily dose of corticosteroids. The overall mortality rate was 4.2%, and the disease-specific mortality rate was 0%.

CONCLUSIONS: The most common culprit drug was carbamazepine, which had strong association with HLA-B*15:02. There was no statistically significant correlation between in-hospital stay and the average daily dose of corticosteroids. Immune checkpoint inhibitor-related SJS/TEN may have an extended latent period.

PMID:33848012 | DOI:10.1111/ijd.15586

J Magn Reson Imaging. 2021 Apr 13. doi: 10.1002/jmri.27639. Online ahead of print.

ABSTRACT

BACKGROUND: No data are available about normal ranges for native T1 in human myocardium using General Electric (GE) scanners.

PURPOSE: To establish normal ranges for myocardial T1 values and evaluate regional variability and the influence of physiological factors.

STUDY TYPE: Prospective.

SUBJECTS: One hundred healthy volunteers with normal electrocardiogram, no cardiovascular/systemic diseases, or risk factors (age range: 20-70 years; 50 females).

FIELD STRENGTH/SEQUENCE: 1.5 T/Steady-state free precession cine and a modified Look-Locker inversion recovery sequence in diastole (also in systole for 61 volunteers).

ASSESSMENT: Image analysis was performed by operators with >10 years experience in cardiac MR using commercially available software. T1 values were calculated for 16 myocardial segments, and the global value was the mean. Segments were grouped according to circumferential region (anterior, septal, inferior, and lateral) and to level (basal, medial, apical). Twenty images were analyzed twice by the same operator and by a different operator to assess reproducibility.

STATISTICAL TESTS: Independent-samples t-test or Mann-Whitney test; paired sample t-test or Wilcoxon signed-rank test; one-way repeated measures ANOVA or Friedman tests; Pearson’s or Spearman’s correlation. Reproducibility evaluated using coefficient of variability (CoV).

RESULTS: Due to artifacts and/or partial-volume effects, 45/1600 (2.8%) segments were excluded. A good intra- and inter-operator reproducibility was detected (CoV < 5%). There were significant differences in segmental T1 values (P < 0.05). A significant circumferential variability was present (P < 0.05): the mean native T1 value over the lateral region was significantly lower than in the other three regions. An increasing gradient from basal to apical slices was detected (P < 0.05). Segmental and global T1 values were not associated with age (range P = 0.052-0.911) but were significantly lower in males than in females (global: 993 ± 32 vs. 1037 ± 27 ms; P < 0.05) and significantly correlated with heart rate (range R for segmental values = 0.247-0.920; P < 0.05). Almost all segmental T1 values were inversely correlated with wall thickness (R from -0.233 to -0.514; P < 0.05). Systolic T1 values were significantly lower than diastolic values in basal anteroseptal segment, in all medial segments except the inferior one, and in all apical segments (P < 0.05).

DATA CONCLUSION: Myocardial T1 values differ among myocardial regions, are influenced by sex, heart rate, and wall thickness and vary according to the cardiac cycle in healthy adults.

LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.

PMID:33848021 | DOI:10.1002/jmri.27639

J Nephrol. 2021 Apr 13. doi: 10.1007/s40620-021-01020-2. Online ahead of print.

ABSTRACT

BACKGROUND: Growth Differentiation Factor-15 (GDF15) is a member of the TGF-β superfamily. Increased serum GDF15 has been associated with increased risk of chronic kidney disease (CKD) progression. However, no prior studies have addressed the significance of urinary GDF15 in adult CKD.

METHODS: We measured serum and urinary GDF15 in a prospective cohort of 84 patients who underwent kidney biopsy and assessed their association with outcomes (survival, kidney replacement therapy) during a follow-up of 29 ± 17 months.

RESULTS: There was a statistically significant correlation between serum and urine GDF15 values. However, while serum GDF15 values increased with decreasing glomerular filtration rate, urinary GDF15 did not. Immunohistochemistry located kidney GDF15 expression mainly in tubular cells, and kidney GDF15 staining correlated with urinary GDF15 values. Urine GDF15 was significantly higher in patients with a histologic diagnosis of diabetic nephropathy than in diabetic patients without diabetic nephropathy. This was not the case for serum GDF15. Both serum and urine GDF15 were negatively associated with patient survival in multivariate models. However, when both urine and serum GDF15 were present in the model, lower urine GDF15 predicted patient survival [B coefficient (SEM) – 0.395 (0.182) p 0.03], and higher urine GDF15 predicted a composite of mortality or kidney replacement therapy [0.191 (0.06) p 0.002], while serum GDF15 was not predictive. Decision tree analysis yielded similar results. The area under the curve (AUC) of the receiver operating curve (ROC) for urine GDF15 as a predictor of mortality was 0.95 (95% CI 0.89-1.00, p < 0.001).

CONCLUSIONS: In conclusion, urinary GDF15 is associated with kidney histology patterns, mortality and the need for renal replacement therapy (RRT) in CKD patients who underwent a kidney biopsy.

PMID:33847920 | DOI:10.1007/s40620-021-01020-2

Methods Mol Biol. 2021;2281:93-115. doi: 10.1007/978-1-0716-1290-3_6.

ABSTRACT

The ability of magnetic tweezers to apply forces and measure molecular displacements has resulted in its extensive use to study the activity of enzymes involved in various aspects of nucleic acid metabolism. These studies have led to the discovery of key aspects of protein-protein and protein-nucleic acid interaction, uncovering dynamic heterogeneities that are lost to ensemble averaging in bulk experiments. The versatility of magnetic tweezers lies in the possibility and ease of tracking multiple parallel single-molecule events to yield statistically relevant single-molecule data. Moreover, they allow tracking both fast millisecond dynamics and slow processes (spanning several hours). In this chapter, we present the protocols used to study the interaction between E. coli SSB, single-stranded DNA (ssDNA), and E. coli RecQ helicase using magnetic tweezers. In particular, we propose constant force and force modulation assays to investigate SSB binding to DNA, as well as to characterize various facets of RecQ helicase activity stimulation by SSB.

PMID:33847954 | DOI:10.1007/978-1-0716-1290-3_6