Nevin Manimala

Interact Cardiovasc Thorac Surg. 2021 Jul 29:ivab200. doi: 10.1093/icvts/ivab200. Online ahead of print.

ABSTRACT

OBJECTIVES: The ability to accurately estimate the risk of peri-operative mortality after lung resection is important. There are concerns about the performance and validity of existing models developed for this purpose, especially when predicting mortality within 90 days of surgery. The aim of this study was therefore to develop a clinical prediction model for mortality within 90 days of undergoing lung resection.

METHODS: A retrospective database of patients undergoing lung resection in two UK centres between 2012 and 2018 was used to develop a multivariable logistic risk prediction model, with bootstrap sampling used for internal validation. Apparent and adjusted measures of discrimination (area under receiving operator characteristic curve) and calibration (calibration-in-the-large and calibration slope) were assessed as measures of model performance.

RESULTS: Data were available for 6600 lung resections for model development. Predictors included in the final model were age, sex, performance status, percentage predicted diffusion capacity of the lung for carbon monoxide, anaemia, serum creatinine, pre-operative arrhythmia, right-sided resection, number of resected bronchopulmonary segments, open approach and malignant diagnosis. Good model performance was demonstrated, with adjusted area under receiving operator characteristic curve, calibration-in-the-large and calibration slope values (95% confidence intervals) of 0.741 (0.700, 0.782), 0.006 (-0.143, 0.156) and 0.870 (0.679, 1.060), respectively.

CONCLUSIONS: The RESECT-90 model demonstrates good statistical performance for the prediction of 90-day mortality after lung resection. A project to facilitate large-scale external validation of the model to ensure that the model retains accuracy and is transferable to other centres in different geographical locations is currently underway.

PMID:34324664 | DOI:10.1093/icvts/ivab200

Interact Cardiovasc Thorac Surg. 2021 Jul 29:ivab149. doi: 10.1093/icvts/ivab149. Online ahead of print.

ABSTRACT

OBJECTIVES: The purpose of this study was to determine the expression of PD-L1 in oesophageal squamous cell carcinoma (OSCC) and the prognostic factors.

METHODS: PD-L1 expression was investigated by immunohistochemical staining of resected specimens from 50 OSCC patients who were randomly selected from 104 patients with complete follow-up data. The relationships among PD-L1 expression, clinicopathological factors and prognosis were assessed by statistical analysis.

RESULTS: The expression of PD-L1 was positive in 27 (54%, positive cells’ proportion > 25%) and negative in 23 (46%, positive cells proportion ≤25%) of 50 cases, and PD-L1 expression was negative in all pericarcinomatous tissues (P > 0.05). The 5-year survival rate of patients with PD-L1-positive expression was 22.2% (6 of 27), which was less than that of patients with PD-L1-negative expression (47.8%; 11 of 23) (P < 0.05). The results showed significant differences in the depth of tumour invasion, lymph node status, postoperative pathological stage and PD-L1 expression (P < 0.05). Multivariable analysis showed that PD-L1 expression was an independent prognostic factor for survival.

CONCLUSIONS: The depth of tumour invasion, lymph node status, postoperative pathological stage and PD-L1 expression are important factors affecting the prognosis of patients with thoracic OSCC; in particular, high PD-L1 expression was a significant independent poor prognostic factor in thoracic OSCC patients.

PMID:34324661 | DOI:10.1093/icvts/ivab149

Rheumatology (Oxford). 2021 Jul 29:keab570. doi: 10.1093/rheumatology/keab570. Online ahead of print.

ABSTRACT

OBJECTIVE: To estimate the occurrence and relative risks of first ever incident non-cutaneous cancer overall and by 16 sites in patients with RA treated with biologic and targeted synthetic DMARDs (b/tsDMARDs), by time since treatment start, attained age, and time on active treatment.

METHODS: Observational nationwide and population-based cohort study of patients with RA(n = 69 308), treated with TNF inhibitors (TNFi; adalimumab, certolizumab, etanercept, golimumab, infliximab) or other b/tsDMARDs (abatacept, rituximab, baricitinib, tofacitinib and tocilizumab) compared with RA patients not treated with b/tsDMARDs, and matched general population referents (n = 109 532), 2001-2018. Study based on prospectively collected data from the Swedish Rheumatology Quality Register and from other registers, linked to the national Cancer Register. Incidence rates and hazard ratios estimated via Cox regression adjusted for co-morbidities and other health characteristics.

RESULTS: : Based on 8633 incident cancers among RA patients, the overall relative risk of cancer with TNFi (HR = 1.0) was neither increased nor did it change with time since treatment start, time on active treatment, or attained age, when compared with b/tsDMARD-naïve RA. For other b/tsDMARDs, we noted no consistent signal of increased overall risks (HRs ranged from 1.0-1.2), but statistically significant estimates above 1 for abatacept with 2-5 years of active treatment, for older age groups, and between several of the bDMARDs and urinary tract cancer.

CONCLUSION: : TNFi, as used long-term in clinical practice against RA are not linked to increased risks for cancer overall. For other b/tsDMARDs, and for site-specific risks, our results are generally reassuring but contain signals that call for replication.

PMID:34324640 | DOI:10.1093/rheumatology/keab570

Arch Pathol Lab Med. 2021 Jul 29. doi: 10.5858/arpa.2020-0834-OA. Online ahead of print.

ABSTRACT

CONTEXT.—: Multiple articles and surveys in the literature suggest that medical students find a career in pathology undesirable and believe it is disproportionately focused primarily on the autopsy.

OBJECTIVE.—: To measure the effect of applied interventions on medical student attitudes about the field of pathology.

DESIGN.—: This prospective study involving medical students from first through fourth year was conducted as a pilot study in 2 medical schools in the United States. A 2-part anonymous survey regarding interest in pathology as a career and familiarity with the specialty using a 10-point scale was given to first- and second-year medical students before and after they listened to a 10-minute pathology career presentation. The same survey was given to third- and fourth-year medical students before and after a 4-week pathology elective.

RESULTS.—: A total of 121 and 83 students responded to the survey before and after the intervention, respectively. Of the 121 students who responded to the survey before the intervention, 106 (87.6%) had not spent significant time in a pathology laboratory before the intervention. The majority of responses in interest in career, job responsibilities, and features of pathologists before and after the intervention demonstrated a statistically significant difference (P < .001). We compared survey scores of presentation versus 4-week rotation groups before and after the intervention. Students who experienced the presentation did not differ from students who experienced the rotation in the majority of questions related to interest in career, job responsibilities, and features of pathologists.

CONCLUSIONS.—: Our study suggests that pathology exposure strategies can have a beneficial effect on student perceptions of the field and consideration of a career in pathology. Overall, the presentation intervention on the first- and second-year students seemed to have the greatest effect.

PMID:34324631 | DOI:10.5858/arpa.2020-0834-OA

PLoS One. 2021 Jul 29;16(7):e0255384. doi: 10.1371/journal.pone.0255384. eCollection 2021.

ABSTRACT

We aimed to investigate whether antibiotic administration is necessary for patients with uncomplicated right colonic diverticulitis. Data from patients diagnosed with uncomplicated right colonic diverticulitis, who received inpatient treatment at a single center between January 2019 and January 2021, were retrospectively examined. The patients were divided into two groups according to whether antibiotics were administered. The patients were matched between groups using propensity score matching in a 1:1 ratio using logistic regression with the nearest-neighbor method. The primary study outcome was the length of hospital stay, and the secondary outcomes were time to the introduction of sips of water and a soft diet. The study included 138 patients who received antibiotics and 59 who did not. After propensity score matching, 55 patients were assigned to each treatment group. There was no significant difference between the two groups in terms of age (p = 0.772), sex (p>0.999), body mass index (p = 0.121), prehospital symptom duration (p = 0.727), initial body temperature (p = 0.661), white blood cell count (p = 0.688), or C-reactive protein level (p = 0.337). There was also no statistically significant difference in the length of hospital stay between the no antibiotic and antibiotic groups (3.1±0.7 days vs. 3.0±1.0 days, p = 0.584). Additionally, no significant difference was observed between the no antibiotic and antibiotic groups with respect to time to sips of water (2.1±0.7 days vs. 1.8±0.9 days, p = 0.100) and time to the introduction of a soft diet (2.4±0.8 days vs. 2.1±0.9 days, p = 0.125). The findings suggest that routine antibiotics may be not required for treating patients with uncomplicated right colonic diverticulitis.

PMID:34324608 | DOI:10.1371/journal.pone.0255384

PLoS One. 2021 Jul 29;16(7):e0255422. doi: 10.1371/journal.pone.0255422. eCollection 2021.

ABSTRACT

In this study, a network autoregressive model with GARCH effects, denoted by NAR-GARCH, is proposed to depict the return dynamics of stock market indices. A GARCH filter is employed to marginally remove the GARCH effects of each index, and the NAR model with the Granger causality test and Pearson’s correlation test with sharp price movements is used to capture the joint effects caused by other indices with the most updated market information. The NAR-GARCH model is designed to depict the joint effects of nonsynchronous multiple time series in an easy-to-implement and effective way. The returns of 20 global stock indices from 2006 to 2020 are employed for our empirical investigation. The numerical results reveal that the NAR-GARCH model has satisfactory performance in both fitting and prediction for the 20 stock indices, especially when a market index has strong upward or downward movements.

PMID:34324604 | DOI:10.1371/journal.pone.0255422

PLoS One. 2021 Jul 29;16(7):e0255389. doi: 10.1371/journal.pone.0255389. eCollection 2021.

ABSTRACT

In a cluster-randomized trial (CRT), the number of participants enrolled often varies across clusters. This variation should be considered during both trial design and data analysis to ensure statistical performance goals are achieved. Most methodological literature on the CRT design has assumed equal cluster sizes. This scoping review focuses on methodology for unequal cluster size CRTs. EMBASE, Medline, Google Scholar, MathSciNet and Web of Science databases were searched to identify English-language articles reporting on methodology for unequal cluster size CRTs published until March 2021. We extracted data on the focus of the paper (power calculation, Type I error etc.), the type of CRT, the type and the range of parameter values investigated (number of clusters, mean cluster size, cluster size coefficient of variation, intra-cluster correlation coefficient, etc.), and the main conclusions. Seventy-nine of 5032 identified papers met the inclusion criteria. Papers primarily focused on the parallel-arm CRT (p-CRT, n = 60, 76%) and the stepped-wedge CRT (n = 14, 18%). Roughly 75% of the papers addressed trial design issues (sample size/power calculation) while 25% focused on analysis considerations (Type I error, bias, etc.). The ranges of parameter values explored varied substantially across different studies. Methods for accounting for unequal cluster sizes in the p-CRT have been investigated extensively for Gaussian and binary outcomes. Synthesizing the findings of these works is difficult as the magnitude of impact of the unequal cluster sizes varies substantially across the combinations and ranges of input parameters. Limited investigations have been done for other combinations of a CRT design by outcome type, particularly methodology involving binary outcomes-the most commonly used type of primary outcome in trials. The paucity of methodological papers outside of the p-CRT with Gaussian or binary outcomes highlights the need for further methodological development to fill the gaps.

PMID:34324593 | DOI:10.1371/journal.pone.0255389

PLoS One. 2021 Jul 29;16(7):e0255317. doi: 10.1371/journal.pone.0255317. eCollection 2021.

ABSTRACT

BACKGROUND: The assessment of self-reported outcomes in neuromyelitis optica spectrum disorder (NMOSD) is limited by the lack of validated disease-specific measures. The SymptoMScreen (SyMS) is a patient-reported questionnaire for measuring symptom severity in different domains affected by multiple sclerosis (MS), but has not been thoroughly evaluated in NMOSD. The aim of this study was to assess the psychometric properties of the SyMS in a sample of patients with NMOSD.

METHODS: A non-interventional, cross-sectional study in adult subjects with NMOSD (Wingerchuk 2015 criteria) was conducted at 13 neuroimmunology clinics applying the SyMS. A non-parametric item response theory procedure, Mokken analysis, was performed to assess the underlying dimensional structure and scalability of items and overall questionnaire. All analyses were performed with R (v4.0.3) using the mokken library.

RESULTS: A total of 70 patients were studied (mean age: 47.5 ± 15 years, 80% female, mean Expanded Disability Status Scale score: 3.0 [interquartile range 1.5, 4.5]). Symptom severity was low (median SyMS score: 19.0 [interquartile range 10.0, 32.0]). The SyMS showed a robust internal reliability (Cronbach’s alpha: 0.90 [95% confidence interval 0.86, 0.93]) and behaved as a unidimensional scale with all items showing scalability coefficients > 0.30. The overall SyMS scalability was 0.45 conforming to a medium scale according to Mokken’s criteria. Fatigue and body pain were the domains with the highest scalability coefficients. The SyMS was associated with disability (rho: 0.586), and physical and psychological quality of life (rho: 0.856 and 0.696, respectively).

CONCLUSIONS: The SyMS shows appropriate psychometric characteristics and may constitute a valuable and easy-to-implement option to measure symptom severity in patients with NMOSD.

PMID:34324586 | DOI:10.1371/journal.pone.0255317

PLoS One. 2021 Jul 29;16(7):e0255221. doi: 10.1371/journal.pone.0255221. eCollection 2021.

ABSTRACT

Tendons are responsive to mechanical loading and their properties are often the target of intervention programs. The tendon’s mechanical properties, particularly stiffness, also govern its function, therefore changes to these properties could have substantial influence on energy-saving mechanisms during activities utilizing the stretch-shortening cycle. We investigated Achilles tendon (AT) function in vivo during walking with respect to a training intervention that elicited significant increases in AT stiffness. 14 men and women completed 12-weeks of isometric plantarflexor strength training that increased AT stiffness, measured during isometric MVC, by ~31%. Before and after the intervention, participants walked shod at their preferred velocity on a fully-instrumented treadmill. Movement kinematics, kinetics and displacement of the gastrocnemius medialis muscle-tendon junction were captured synchronously using 3D motion capture and ultrasound imaging, respectively. A MANOVA test was used to examine changes in AT force, stress, strain, stiffness, Young’s modulus, hysteresis and strain energy, measured during walking, before and following strength training. All were non-significant for a main effect of time, therefore no follow-up statistical tests were conducted. Changes in joint kinematics, tendon strain, velocity, work and power and muscle activity during the stance phase were assessed with 1D statistical parametric mapping, all of which also demonstrated a lack of change in response to the intervention. This in vivo examination of tendon function in walking provides an important foundation for investigating the functional consequences of training adaptations. We found substantial increases in AT stiffness did not impact on tendon function during walking. AT stiffness measured during walking, however, was unchanged with training, which suggests that increases in stiffness may not be evident across the whole force-elongation relation, a finding which may help explain previously mixed intervention results and guide future investigations in the functional implications of tendon adaptation.

PMID:34324575 | DOI:10.1371/journal.pone.0255221

PLoS One. 2021 Jul 29;16(7):e0255370. doi: 10.1371/journal.pone.0255370. eCollection 2021.

ABSTRACT

The aim of this study was to evaluate the potential of diatom (microalgae) biomass as a lice-reducing ingredient in salmon feed. The original hypothesis was based on the fact that polyunsaturated aldehydes (PUAs), e.g. 2-trans, 4-trans decadenial (A3) produced by diatoms can function as grazing deterrents and harm copepod development. Salmon lice (Lepeophtheirus salmonis) is a copepod, and we intended to test if inclusion of diatom biomass in the feed could reduce the infestation of lice on salmon. We performed experiments where salmon kept in tanks were offered four different diets, i.e. basic feed with diatoms, fish oil, Calanus sp. oil or rapeseed oil added. After a feeding period of 67 days a statistically representative group of fishes, tagged with diet group origin, were pooled in a 4000L tank and exposed to salmon lice copepodites whereafter lice infestation was enumerated. Salmon from all four diet groups had good growth with SGR values from 1.29 to 1.44% day-1 (increase from ca. 130 g to 350 g). At the termination of the experiment the number of lice on salmon offered diatom feed were statistically significantly lower than on salmon fed the other diets. Mean lice infestation values increased from diatom feed through Calanus and fish oil to standard feed with terrestrial plant ingredients. Analysis of the chemical composition of the different diets (fatty acids, amino acids) failed to explain the differences in lice infestation. The only notable result was that diatom and Calanus feed contained more FFA (free fatty acids) than feed with fish oil and the control feed. None of the potential deleterious targeted polyunsaturated aldehydes could be detected in skin samples of the salmon. What was exclusive for salmon that experienced reduced lice was diatom inclusion in the feed. This therefore still indicates the presence of some lice deterring ingredient, either in the feed, or an ingredient can have triggered production of an deterrent in the fish. An obvious follow up of this will be to perform experiments with different degrees of diatom inclusion in the feeds, i.e. dose response experiments combined with targeted PUA analyses, as well as to perform large scale experiments under natural conditions in aquaculture pens.

PMID:34324572 | DOI:10.1371/journal.pone.0255370