Category: Statistics

Environ Sci Pollut Res Int. 2021 Mar 5. doi: 10.1007/s11356-021-13207-y. Online ahead of print.

ABSTRACT

Adsorptive separation of heavy metals from wastewater is a viable approach to reuse it and avoid environmental pollution. The productive employment of adsorptive separation at a commercial scale, however, relies on the optimized conditions of an adsorber bed holding maximum and selective isolation of the heavy metals. The experimental route includes a significant trial and error approach, is time-consuming, involves operating cost, and remains economically unattractive. Contrarily, simulation of a mathematical model mimicking the adsorption system along with experimental validation can significantly minimize optimization efforts and suggests the best conditions of separation. In this work, a convective-dispersive model and adsorption model for fixed bed adsorption of copper (Cu), chromium (Cr), and cadmium (Cd) metals over wheat bran biosorbent are simulated using the gPROMS tool for benchmarking. The influence of feed flow rate, bed height, and metal concentration is studied, and breakthrough profiles of all heavy metals are predicted and matched with the literature. The error values (R² and RMSE) and Chi-squared values determined from gPROMS simulations matched well with the previously available MATLAB-simulated data. After a successful benchmarking, we modeled pilot-scale adsorption of Cr on coconut coir (or Biosorbent) in a gPROMS simulation environment. A detailed method and algorithm of gPROMS simulation for Cr isolation is provided. The influence of feed flow rate, bed height, and initial metal concentration is studied on the breakthrough curves of the Cr. The optimum operating condition for the pilot-scale isolation of Cr from the water is suggested. The parameters, such as the axial dispersion coefficient and distribution coefficient, are determined.

PMID:33674977 | DOI:10.1007/s11356-021-13207-y

Clin Rheumatol. 2021 Mar 5. doi: 10.1007/s10067-021-05670-2. Online ahead of print.

ABSTRACT

OBJECTIVE: Considering the pathologic significance of inflammation and oxidative stress in rheumatoid arthritis (RA) as well as the antioxidant, anti-inflammatory and hypolipidemic effects of melatonin, the current research is designed to investigate the effect of melatonin supplementation on disease activity, oxidative stress, inflammatory, and metabolic parameters in RA patients.

METHODS: In this randomized double-blind, placebo-controlled trial, 64 RA cases were selected and randomly assigned into 2 groups to take 6 mg/day melatonin or placebo for 12 weeks. Before and after trial, serum malondialdehyde (MDA), total antioxidant capacity (TAC), erythrocyte sedimentation rate (ESR), lipid profile, fasting blood sugar (FBS), and insulin levels were measured and disease activity was determined by disease activity score-28 (DAS-28).

RESULTS: Compared to the baseline, melatonin significantly decreased DAS-28, ESR, MDA, and LDL-C by 50.5%, 59%, 97%, and 13%, respectively (P<0.001) and significantly increased TAC by 89% (P=0.013) and HDL-C by 22% (P<0.001). After treatment, considerable differences were only seen between the two groups in serum MDA (P<0.001) and LDL-C (P=0.007) concentrations, adjusted for baseline measures. Moreover, there were no significant changes in DAS-28, ESR, TAC, triglyceride, total cholesterol, HDL-C, FBS, and insulin levels compared to placebo group (P>0.05).

CONCLUSIONS: Although melatonin supplementation had no beneficial effects on DAS-28, it could lower serum MDA and LDL-C levels. It seems that melatonin supplementation should not be used as a replace for routine drugs prescribed in RA treatment. Further investigations should be conducted to fully understand the effects of melatonin in RA. Key Points • Compared to baseline, melatonin significantly decreased DAS-28, ESR, MDA, and LDL-C and significantly increased TAC and HDL-C. • After treatment, considerable differences were only seen between melatonin and placebo groups in serum MDA and LDL-C concentrations. • After treatment, there were no significant changes in DAS-28, ESR, TAC, triglyceride, total cholesterol, HDL-C, FBS, and insulin levels compared to the placebo group.

PMID:33674988 | DOI:10.1007/s10067-021-05670-2

Abdom Radiol (NY). 2021 Mar 6. doi: 10.1007/s00261-021-02988-y. Online ahead of print.

ABSTRACT

PURPOSE: To identify specific contrast-enhanced CT (CECT) findings and develop a predictive model with logistic regression to differentiate fat-poor angiomyolipomas (fpAML) from papillary renal cell carcinomas (pRCC).

METHODS: This is a single-institution retrospective study that assess CT features of histologically proven 67 pRCC and 13 fpAML. CECT variables were studied by means of univariate logistic regression. Variables included patients’ demographics, tumor attenuation (unenhanced and at arterial, venous and excretory post-contrast phases), type of enhancement, morphological features (axial long and short diameters, long-short axis ratio (LSR) and tumor to kidney angle interface) and presence of visible calcifications or vessels. Those variables with a p ≤ 0.05 underwent standard stepwise logistic regression to find predictive combinations of clinical variables. Best models were evaluated by AUROC curves and were subjected to Leave-one-out cross validation to assess their robustness.

RESULTS: Odds ratio (OR) between pRCC and fpAML was statistically significant for patient’s gender, tumor attenuation in arterial, venous and excretory phases, tumor’s long diameter, short diameter, LSR, type of enhancement, presence of intratumoral vessels and tumor-kidney angle interface. The best predictive model resulted in an area under the curve (AUC) of 0.971 and included gender, tumor-kidney angle interface and venous attenuation with the following equation: Log(p/1 – p) = – 2.834 + 4.052 * gender + – 0.066 * AngleInterface + 0.074 * VenousphaseHU.

CONCLUSIONS: The combination of patients’ gender, tumor to kidney angle interface and venous enhancement helps to distinguish fpAML from pRCC.

PMID:33674961 | DOI:10.1007/s00261-021-02988-y

Sleep Breath. 2021 Mar 5. doi: 10.1007/s11325-021-02337-9. Online ahead of print.

ABSTRACT

PURPOSE: The aim of the present study was to detect the prevalence of temporomandibular disorders (TMD) in patients with untreated obstructive sleep apnea (OSA) and to compare the results with healthy controls, matched for sex and age.

METHODS: Forty-one consecutive patients with OSA were prospectively recruited from the Department of Otorhinolaryngology at the A. Gemelli Hospital prior to undergoing any treatment for OSA and independently of OSA severity. All patients underwent a complete TMD examination according to the diagnostic criteria for temporomandibular disorders (DC/TMD) protocol. The same examination was performed on 41 healthy controls matched for sex and age. Chi-squared test was used to compare results between the two groups.

RESULTS: Of the 41 patients with OSA, 21 (51%) presented signs and/or symptoms of TMD compared to 13 of 41 subjects (32%) from the control group. Headache attributed to TMD and disc displacement with reduction were the most common diagnoses, with a statistically significant difference between the two groups (p<0.05).

CONCLUSIONS: The prevalence of TMD signs and symptoms is significantly higher in untreated patients with OSA compared to healthy controls.

PMID:33674964 | DOI:10.1007/s11325-021-02337-9

Am J Clin Nutr. 2021 Mar 1:nqaa422. doi: 10.1093/ajcn/nqaa422. Online ahead of print.

ABSTRACT

BACKGROUND: B vitamins have been associated with the risk and progression of colorectal cancer (CRC), given their central roles in nucleotide synthesis and methylation, yet their association with quality of life in established CRC is unclear.

OBJECTIVES: To investigate whether quality of life 6 months postdiagnosis is associated with: 1) circulating concentrations of B vitamins and related biomarkers 6 months postdiagnosis; 2) changes in these concentrations between diagnosis and 6 months postdiagnosis; 3) B-vitamin supplement use 6 months postdiagnosis; and 4) changes in B-vitamin supplement use between diagnosis and 6 months postdiagnosis.

METHODS: We included 1676 newly diagnosed stage I-III CRC patients from 3 prospective European cohorts. Circulating concentrations of 9 biomarkers related to the B vitamins folate, riboflavin, vitamin B6, and cobalamin were measured at diagnosis and 6 months postdiagnosis. Information on dietary supplement use was collected at both time points. Health-related quality of life (global quality of life, functioning scales, and fatigue) was assessed by the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire 6 months postdiagnosis. Confounder-adjusted linear regression analyses were performed, adjusted for multiple testing.

RESULTS: Higher pyridoxal 5′-phosphate (PLP) was cross-sectionally associated with better physical, role, and social functioning, as well as reduced fatigue, 6 months postdiagnosis. Associations were observed for a doubling in the hydroxykynurenine ratio [3-hydroxykynurenine: (kynurenic acid + xanthurenic acid + 3-hydroxyanthranilic acid + anthranilic acid); an inverse marker of vitamin B6] and both reduced global quality of life (β = -3.62; 95% CI: -5.88, -1.36) and worse physical functioning (β = -5.01; 95% CI: -7.09, -2.94). Dose-response relations were observed for PLP and quality of life. No associations were observed for changes in biomarker concentrations between diagnosis and 6 months. Participants who stopped using B-vitamin supplements after diagnosis reported higher fatigue than nonusers.

CONCLUSIONS: Higher vitamin B6 status was associated with better quality of life, yet limited associations were observed for the use of B-vitamin supplements. Vitamin B6 needs further study to clarify its role in relation to quality of life.

PMID:33668069 | DOI:10.1093/ajcn/nqaa422

J Gastroenterol Hepatol. 2021 Mar 5. doi: 10.1111/jgh.15482. Online ahead of print.

ABSTRACT

BACKGROUND & AIMS: The rising incidence of chronic liver disease (CLD) has increased the need for early recognition. This systematic review assesses the diagnostic accuracy of the Enhanced Liver Fibrosis (ELF) test in cases of advanced fibrosis and cirrhosis due to multiple aetiologies in at-risk populations.

METHODS: Studies evaluating the ELF accuracy in identifying advanced fibrosis or cirrhosis, defined as METAVIR stage F ≥ 3 and F=4 or equivalent, in patients with non-alcoholic fatty liver disease (NAFLD), alcohol liver disease (ALD), or viral hepatitis were included. Liver biopsy was used as the reference standard. Medline and Embase databases were searched. The QUADAS-2 tool was used as a framework to assess risk of bias and applicability. The Area Under the Receiver Operator Curve (AUROC) was extracted as a summary measure of diagnostic accuracy.

RESULTS: 36 studies were included: 11 hepatitis C, 4 hepatitis B, 9 NAFLD, 2 ALD, and 10 mixed. The ELF test showed good diagnostic performance in detecting advanced fibrosis in patients with viral hepatitis (AUROC 0.69-0.98) and excellent performance in NAFLD (AUROC 0.78 to 0.97) and ALD (AUROC from 0.92 to 0.94). There is also evidence of good diagnostic performance for detecting cirrhosis in patients with viral hepatitis (AUROC 0.63 to 0.99), good performance in NAFLD (AUROC 0.85 to 0.92) and excellent performance in patients with ALD (AUROC 0.93 to 0.94).

CONCLUSION: This systematic review supports the use of the ELF test across a range of CLD as a possible alternative to liver biopsy in selected cases.

PMID:33668077 | DOI:10.1111/jgh.15482

J Neurosurg. 2021 Mar 5:1-9. doi: 10.3171/2020.9.JNS201109. Online ahead of print.

ABSTRACT

OBJECTIVE: In transcranial magnetic resonance imaging-guided focused ultrasound (TcMRgFUS), a high skull density ratio (SDR) is advantageous to achieve a sufficiently high temperature at the target. However, it is not easy to estimate the temperature rise because the SDR shows different values depending on the reconstruction filter used. The resolution characteristic of a computed tomography (CT) image depends on a modulation transfer function (MTF) defined by the reconstruction filter. Differences in MTF induce unstable SDRs. The purpose of this study was both to standardize SDR by developing a method to correct the MTF and to enable effective patient screening prior to TcMRgFUS treatment and more accurate predictions of focal temperature.

METHODS: CT images of a skull phantom and five subjects were obtained using eight different reconstruction filters. A frequency filter (FF) was calculated using the MTF of each reconstruction filter, and the validity of SDR standardization was evaluated by comparing the variation in SDR before and after FF correction. Subsequently, FF processing was similarly performed using the CT images of 18 patients who had undergone TcMRgFUS, and statistical analyses were performed comparing the relationship between the SDRs before and after correction and the maximum temperature in the target during TcMRgFUS treatment.

RESULTS: The FF was calculated for each reconstruction filter based on one manufacturer’s BONE filter. In the CT images of the skull phantom, the SDR before FF correction with five of the other seven reconstruction filters was significantly smaller than that with the BONE filter (p < 0.01). After FF correction, however, a significant difference was recognized under only one condition. In the CT images of the five subjects, variation of the SDR due to imaging conditions was significantly improved after the FF correction. In 18 cases treated with TcMRgFUS, there was no correlation between SDR before FF correction and maximum temperature (rs = 0.31, p > 0.05); however, a strong positive correlation was observed after FF correction (rs = 0.71, p < 0.01).

CONCLUSIONS: After FF correction, the difference in SDR due to the reconstruction filter used is smaller, and the correlation with temperature is stronger. Therefore, the SDR can be standardized by applying the FF, and the maximum temperature during treatment may be predicted more accurately.

PMID:33668032 | DOI:10.3171/2020.9.JNS201109

J Neurosurg. 2021 Mar 5:1-12. doi: 10.3171/2020.7.JNS20257. Online ahead of print.

ABSTRACT

OBJECTIVE: An assessment of the transcranial approach (TCA) and the endoscopic endonasal approach (EEA) for craniopharyngiomas (CPs) according to tumor types has not been reported. The aim of this study was to evaluate both surgical approaches for different types of CPs.

METHODS: A retrospective review of primary resected CPs was performed. A QST classification system based on tumor origin was used to classify tumors into 3 types as follows: infrasellar/subdiaphragmatic CPs (Q-CPs), subarachnoidal CPs (S-CPs), and pars tuberalis CPs (T-CPs). Within each tumor type, patients were further arranged into two groups: those treated via the TCA and those treated via the EEA. Patient and tumor characteristics, surgical outcomes, and postoperative complications were obtained. All variables were statistically analyzed between surgical groups for each tumor type.

RESULTS: A total of 315 patients were included in this series, of whom 87 were identified with Q-CPs (49 treated via TCA and 38 via EEA); 56 with S-CPs (36 treated via TCA and 20 via EEA); and 172 with T-CPs (105 treated via TCA and 67 via EEA). Patient and tumor characteristics were equivalent between both surgical groups in each tumor type. The overall gross-total resection rate (90.5% TCA vs 91.2% EEA, p = 0.85) and recurrence rate (8.9% TCA vs 6.4% EEA, p = 0.35) were similar between surgical groups. The EEA group had a greater chance of visual improvement (61.6% vs 35.8%, p = 0.01) and a decreased risk of visual deterioration (1.6% vs 11.0%, p < 0.001). Of the patients with T-CPs, postoperative hypothalamic status was better in the TCA group than in the EEA group (p = 0.016). Postoperative CSF leaks and nasal complication rates occurred more frequently in the EEA group (12.0% vs 0.5%, and 9.6% vs 0.5%; both p < 0.001). For Q-CPs, EEA was associated with an increased gross-total resection rate (97.4% vs 85.7%, p = 0.017), decreased recurrence rate (2.6% vs 12.2%, p = 0.001), and lower new hypopituitarism rate (28.9% vs 57.1%, p = 0.008). The recurrence-free survival in patients with Q-CPs was also significantly different between surgical groups (log-rank test, p = 0.037). The EEA required longer surgical time for T-CPs (p = 0.01).

CONCLUSIONS: CPs could be effectively treated by radical surgery with favorable results. Both TCA and EEA have their advantages and limitations when used to manage different types of tumors. Individualized surgical strategies based on tumor growth patterns are mandatory to achieve optimal outcomes.

PMID:33668037 | DOI:10.3171/2020.7.JNS20257

Am J Clin Nutr. 2021 Mar 1:nqaa440. doi: 10.1093/ajcn/nqaa440. Online ahead of print.

ABSTRACT

BACKGROUND: There is an emerging viewpoint that change in body weight is not sufficiently sensitive to promptly identify clinically meaningful change in body composition, such as skeletal muscle depletion.

OBJECTIVES: We aimed to determine whether body weight stability is associated with skeletal muscle depletion and whether skeletal muscle depletion is prognostic of death independently of change in body weight.

METHODS: This retrospective cohort included 1921 patients with stage I-III colorectal cancer. Computed tomography (CT)-based skeletal muscle characteristics and body weight were measured at diagnosis and after a mean 15.0-mo follow-up. Body weight stability was defined as weight change less than ±5% during follow-up. Sarcopenia and myosteatosis were defined using established thresholds for patients with cancer. Multivariable-adjusted logistic and flexible parametric proportional hazards survival models were used to quantify statistical associations.

RESULTS: At follow-up, 1026 (53.3%) patients were weight stable. Among patients with weight stability, incident sarcopenia and myosteatosis occurred in 8.5% (95% CI: 6.3%, 10.6%) and 13.5% (95% CI: 11.1%, 15.9%), respectively. Men were more likely to be weight stable than were women (56.7% compared with 49.9%; P = 0.04). Weight-stable men were less likely to develop incident sarcopenia (5.4% compared with 15.4%; P = 0.003) and myosteatosis (9.3% compared with 20.8%; P = 0.001) than weight-stable women. Among all patients, the development of incident sarcopenia (HR: 1.40; 95% CI: 1.02, 1.91) and of myosteatosis (HR: 1.41; 95% CI: 1.05, 1.90) were associated with a higher risk of death, independently of change in body weight. Patient sex did not modify the relation between skeletal muscle depletion and death.

CONCLUSIONS: Body weight stability masks clinically meaningful skeletal muscle depletion. Body composition quantified using clinically acquired CT images may provide a vital sign to identify patients at increased risk of death. These data may inform the design of future cachexia trials.

PMID:33668052 | DOI:10.1093/ajcn/nqaa440

Am J Clin Nutr. 2021 Mar 1:nqaa439. doi: 10.1093/ajcn/nqaa439. Online ahead of print.

ABSTRACT

BACKGROUND: Choline deficiency has numerous negative health consequences; although the preponderance of the US population consumes less than the recommended Adequate Intake (AI), clinical assessment of choline status is difficult. Further, several pathways involved in primary metabolism of choline are estrogen-sensitive and the AI for premenopausal women is lower than that for men.

OBJECTIVES: We sought to determine whether in vivo magnetic resonance spectroscopy (MRS) of liver and/or isotope-dilution MS of plasma could identify biomarkers reflective of choline intake (preregistered primary outcomes 1 and 2, secondary outcome 1). Determination of whether biomarker concentrations showed sex dependence was a post hoc outcome. This substudy is a component of a larger project to identify a clinically useful biomarker panel for assessment of choline status.

METHODS: In a double-blind, randomized, crossover trial, people consumed 3 diets, representative of ∼100%, ∼50%, and ∼25% of the choline AI, for 2-wk periods. We measured the concentrations of choline and several metabolites using 1H single-voxel MRS of liver in vivo and using 2H-labeled isotope dilution MS of several choline metabolites in extracted plasma.

RESULTS: Plasma concentrations of 2H9-choline, unlabeled betaine, and 2H9-betaine, and the isotopic enrichment ratio (IER) of betaine showed highly significant between-diet effects (q < 0.0001), with unlabeled betaine concentration decreasing 32% from highest to lowest choline intake. Phosphatidylcholine IER was marginally significant (q = 0.03). Unlabeled phosphatidylcholine plasma concentrations did not show between-diet effects (q = 0.34). 2H9 (trimethyl)-phosphatidylcholine plasma concentrations (q = 0.07) and MRS-measured total soluble choline species liver concentrations (q = 0.07) showed evidence of between-diet effects but this was not statistically significant.

CONCLUSIONS: Although MRS is a more direct measure of choline status, variable spectral quality limited interpretation. MS analysis of plasma showed clear correlation of plasma betaine concentration, but not plasma phosphatidylcholine concentration, with dietary choline intake. Plasma betaine concentrations also correlate with sex status (premenopausal women, postmenopausal women, men).This trial was registered at clinicaltrials.gov as NCT03726671.

PMID:33668062 | DOI:10.1093/ajcn/nqaa439