Tag: nevin manimala

Stat Med. 2023 Jun 13. doi: 10.1002/sim.9817. Online ahead of print.

ABSTRACT

External validation of the discriminative ability of prediction models is of key importance. However, the interpretation of such evaluations is challenging, as the ability to discriminate depends on both the sample characteristics (ie, case-mix) and the generalizability of predictor coefficients, but most discrimination indices do not provide any insight into their respective contributions. To disentangle differences in discriminative ability across external validation samples due to a lack of model generalizability from differences in sample characteristics, we propose propensity-weighted measures of discrimination. These weighted metrics, which are derived from propensity scores for sample membership, are standardized for case-mix differences between the model development and validation samples, allowing for a fair comparison of discriminative ability in terms of model characteristics in a target population of interest. We illustrate our methods with the validation of eight prediction models for deep vein thrombosis in 12 external validation data sets and assess our methods in a simulation study. In the illustrative example, propensity score standardization reduced between-study heterogeneity of discrimination, indicating that between-study variability was partially attributable to case-mix. The simulation study showed that only flexible propensity-score methods (allowing for non-linear effects) produced unbiased estimates of model discrimination in the target population, and only when the positivity assumption was met. Propensity score-based standardization may facilitate the interpretation of (heterogeneity in) discriminative ability of a prediction model as observed across multiple studies, and may guide model updating strategies for a particular target population. Careful propensity score modeling with attention for non-linear relations is recommended.

PMID:37311563 | DOI:10.1002/sim.9817

Stat Med. 2023 Jun 13. doi: 10.1002/sim.9823. Online ahead of print.

ABSTRACT

The receiver operating characteristic (ROC) curve is a powerful statistical tool and has been widely applied in medical research. In the ROC curve estimation, a commonly used assumption is that larger the biomarker value, greater severity the disease. In this article, we mathematically interpret “greater severity of the disease” as “larger probability of being diseased.” This in turn is equivalent to assume the likelihood ratio ordering of the biomarker between the diseased and healthy individuals. With this assumption, we first propose a Bernstein polynomial method to model the distributions of both samples; we then estimate the distributions by the maximum empirical likelihood principle. The ROC curve estimate and the associated summary statistics are obtained subsequently. Theoretically, we establish the asymptotic consistency of our estimators. Via extensive numerical studies, we compare the performance of our method with competitive methods. The application of our method is illustrated by a real-data example.

PMID:37311560 | DOI:10.1002/sim.9823

Eur J Dent. 2023 Jun 13. doi: 10.1055/s-0043-1768468. Online ahead of print.

ABSTRACT

OBJECTIVE: This study aimed to preliminarily evaluate the expression of two putative tumor suppressor proteins, including chronic lymphocytic leukemia deletion gene 7 (CLLD7) and chromosome condensation 1-like (CHC1L) proteins in oral squamous cell carcinoma (OSCC).

MATERIALS AND METHODS: Expression of CLLD7 and CHC1L proteins was analyzed in 19 OSCC and 12 normal oral mucosa (NOM) using immunohistochemistry. The percentage of positive cells and intensity of staining were semiquantitatively assessed and expressed with an immunoreactive score. The number of positive cells at various subcellular localizations was evaluated and presented in percentages. The immunoreactivity scores and percentages of positive cells at various localizations were compared between the normal and OSCC groups with statistical significance at p-value less than 0.05.

RESULTS: According to immunohistochemical analysis, the immunoreactivity scores for both CLLD7 and CHC1L were higher in NOM than those of OSCC. Analysis of CLLD7 localization revealed predominant nuclear staining at basal and parabasal areas in NOM, whereas more cytoplasmic staining was observed in OSCC. For CHC1L, nuclear staining was prominent in NOM. In contrast, significantly increased plasma membrane staining was detected in OSCC.

CONCLUSION: The expression of CLLD7 and CHC1L proteins was reduced in OSCC. Alterations in the subcellular localization of these two proteins in OSCC were also demonstrated. These preliminary results suggest that CLLD7 and CHC1L are aberrantly expressed in OSCC. The precise mechanisms of these putative tumor suppressor proteins in OSCC require future studies.

PMID:37311552 | DOI:10.1055/s-0043-1768468

Eur J Dent. 2023 Jun 13. doi: 10.1055/s-0043-1768471. Online ahead of print.

ABSTRACT

OBJECTIVE: To evaluate and compare the friction of different ligature modes used in orthodontics, and to propose a new ligature model for conventional brackets (“H low-friction orthodontic ligature).

MATERIALS AND METHODS: Samples were randomly divided into seven experimental groups: (1) resin H ligature (H3D), designed by the authors of this study and produced in a 3D printer, with conventional bracket; (2) metal H ligature (HFM), with conventional bracket; (3) passive self-ligating bracket (SLP); (4) “8” low-friction unconventional elastic (LT8), with conventional bracket; (5) loose conventional metal ligature (MLS), with conventional bracket; (6) conventional metal ligature fully tightened (MLT), with conventional bracket; (7) conventional elastic ligature (CEL), with conventional bracket-control. All samples were subjected to mechanical static friction testing using the EMIC DL 2000 universal testing machine.

STATISTICAL ANALYSIS: To assess the normality requirement, the Shapiro-Wilk test was used, which showed a non-normal distribution for the means of the groups (p < 0.05). Therefore, statistical tests were performed to assess the existence of statistically significant differences between the groups through the Kruskal-Wallis, followed by Dunn’s test, pairwise comparison, p < 0.05.

RESULTS: The results obtained showed lower friction values for HFM (0.002 kgf), SLP (0.003 kgf), and LT8 (0.004 kgf)-these did not differ statistically from each other. These were followed by H3D (0.020 kgf), MLS (0.049 kgf), CEL (0.12 kgf), and, finally, MLT (0.21 kgf).

CONCLUSION: The lowest friction value was found for the metal H ligature, similar to the self-ligating bracket and the “8” low-friction unconventional elastic. The resin H ligature presented intermediate friction values and the highest friction force was found for the MLT group.

PMID:37311551 | DOI:10.1055/s-0043-1768471

Bioresour Technol. 2023 Jun 11:129307. doi: 10.1016/j.biortech.2023.129307. Online ahead of print.

ABSTRACT

Microbial electrochemical system autotrophic denitrification has attracted much attention due to its cost-efficiency and clean advantages. The autotrophic denitrification rate highly depends on the input electrons to the cathode. In this study, agricultural waste corncob was filled into sandwich structure anode as low-cost carbon source for electron production. The COMSOL software was used to guide the construction of sandwich structure anode to control carbon source release and enhance electron collection, including suitable pore size (4 mm) and current collector arrangement (five branches). Optimized sandwich structure anode system with the help of 3D printing obtained a higher denitrification efficiency (21.79 ± 0.22 gNO₃^–-N/m³d) than anodic systems without pore and current collector. Statistical analysis showed that enhanced autotrophic denitrification efficiency was the responsible for enhanced denitrification performance of the optimized anode system. This study provides a strategy to improve the autotrophic denitrification performance of the microbial electrochemical system by optimizing the anode structure.

PMID:37311526 | DOI:10.1016/j.biortech.2023.129307

J Subst Use Addict Treat. 2023 Jun 10:209103. doi: 10.1016/j.josat.2023.209103. Online ahead of print.

ABSTRACT

BACKGROUND: People with opioid use disorder (OUD) are overrepresented in US correctional facilities and experience disproportionately high risk for overdose after release. Medications for OUD (MOUD) are highly efficacious but not available to most incarcerated individuals. In 2018, Vermont began providing MOUD for all incarcerated individuals with OUD statewide. In 2020, the COVID-19 state of emergency began. We assessed the impact of both events on MOUD utilization and treatment outcomes.

METHODOLOGY: Analyses linked Vermont Department of Corrections administrative data and Medicaid claims data between 07/01/2017 and 03/31/2021. The study used logistic regression to analyze treatment engagement among all incarcerated individuals in Vermont. Multilevel modeling assessed change in clinical outcomes among release episodes that occurred among individuals with an OUD diagnosis Medicaid claim.

RESULTS: Prescriptions for MOUD while incarcerated increased from 0.8 % to 33.9 % of the incarcerated population after MOUD implementation (OR = 67.4) and subsequently decreased with the onset of COVID-19 to 26.6 % (OR = 0.7). After MOUD implementation, most prescriptions (63.1 %) were to individuals who had not been receiving MOUD prior to incarceration, but this figure decreased to 53.9 % with the onset of COVID-19 (OR = 0.7). Prescriptions for MOUD within 30 days after release increased from 33.9 % of those with OUD before to 41.0 % after MOUD implementation (OR = 1.4) but decreased to 35.6 % with the onset of COVID-19 (OR = 0.8). Simultaneously, opioid-related nonfatal overdoses within 30 days after release decreased from 1.2 % before to 0.8 % after statewide MOUD implementation (OR = 0.3) but increased to 1.9 % during COVID-19 (OR = 3.4). Fatal overdoses within 1 year after release decreased from 27 deaths before to ≤10 after statewide MOUD implementation and remained ≤10 during COVID-19.

CONCLUSIONS: This longitudinal evaluation demonstrated increased treatment engagement and a decrease in opioid-related overdose following implementation of MOUD in a statewide correctional system. In contrast, these improvements were somewhat attenuated with the onset of COVID-19, which was associated with decreased treatment engagement and an increase in nonfatal overdoses. Considered together, these findings demonstrate the benefits of statewide MOUD for incarcerated individuals as well as the need to identify and address barriers to continuation of care following release from incarceration in the context of COVID-19.

PMID:37311520 | DOI:10.1016/j.josat.2023.209103

Clin Res Hepatol Gastroenterol. 2023 Jun 11:102154. doi: 10.1016/j.clinre.2023.102154. Online ahead of print.

ABSTRACT

BACKGROUND AND AIM: Autoimmune gastritis (AIG) is a prominent risk factor for pernicious anemia (PA) and gastric neoplasia. This study aimed to investigate the clinicopathological characteristics of AIG patients in China, with a focus on those who had positive anti-intrinsic factor antibodies (AIFA).

METHODS: A total of 103 AIG patients who were diagnosed between January 2018 and August 2022 were reviewed in a large academic tertiary teaching hospital. Patients were divided into two groups based on the presence or absence of AIFA, and their serologic and histopathological characteristics were analyzed.

RESULTS: The mean age of the 103 AIG patients was 54.16±11.92 years (range 23-79), with 69 (66.99%) being women. AIFA were present in 28.16% of patients. Patients with AIFA-positive had a higher risk of PA than those with AIFA-negative, as demonstrated by a larger mean corpuscular volume (MCV), lower hemoglobin level, and lower vitamin B-12 level (P<0.05). There were no statistically significant differences in gastric histopathology, gastrin level, and pepsinogen level when patients were divided into AIFA-positive and AIFA-negative group. Of the 103 cases, 34 (33.01%) were concomitant with other autoimmune diseases, with autoimmune thyroid diseases being the most common (25.24%, 26/103). Thyroid peroxidase antibody, which accounted for 45.45% (25/55), was the most prevalent thyroid antibody, followed by anti-thyroglobulin antibody (34.55%, 19/55), thyroid stimulating antibody (12.73%, 7/55), and thyrotropin receptor antibody (3.64%, 2/55).

CONCLUSION: This study highlights the increased risk of severe anemia in AIFA-positive AIG patients, particularly for PA. Clinicians should consider the presence of AIFA as a warning sign for PA and prioritize early diagnosis and appropriate treatment to prevent serious complications.

PMID:37311519 | DOI:10.1016/j.clinre.2023.102154

J Clin Epidemiol. 2023 Jun 11:S0895-4356(23)00144-0. doi: 10.1016/j.jclinepi.2023.06.003. Online ahead of print.

ABSTRACT

OBJECTIVE: To develop a methodological framework to identify and prioritize personomic markers (e.g., psychosocial situation, beliefs…) to consider for personalizing interventions and to test in smoking cessation interventions.

STUDY DESIGN AND SETTING: (1) We identified potential personomic markers considered in protocols of personalized interventions, in reviews of predictors of smoking cessation, and in interviews with general practitioners. (2) Physicians, and patient smokers or former smokers selected the markers they considered most relevant during online paired comparison experiments. Data were analyzed with Bradley Terry Luce models.

RESULTS: Thirty-six personomic markers were identified from research evidence. They were evaluated by 795 physicians (median age: 34, IQR [30-38]; 95% general practitioners) and 793 patients (median age: 54, IQR [42-64], 71.4% former smokers) during 11963 paired comparisons. Physicians identified patients’ motivation for quitting (e.g., Prochaska stages), patients’ preferences, and patients’ fears/beliefs (e.g., concerns about weight gain) as the most relevant elements to personalize smoking cessation. Patients considered their motivation for quitting, smoking behavior (e.g., smoking at home/at work), and tobacco dependence (e.g., Fagerström Test) as the most relevant elements to consider.

CONCLUSION: We provide a methodological framework to prioritize which personomic markers should be considered when developing smoking cessation interventions.

PMID:37311514 | DOI:10.1016/j.jclinepi.2023.06.003

Transplant Cell Ther. 2023 Jun 11:S2666-6367(23)01353-2. doi: 10.1016/j.jtct.2023.06.008. Online ahead of print.

ABSTRACT

INTRODUCTION: Graft-versus host disease (GVHD) is the major toxicity of allogeneic hematopoietic cell transplant (HCT). We hypothesized that the GVHD prophylaxis regimen of post-transplant cyclophosphamide (PTCy), tacrolimus (Tac) and mycophenolate mofetil (MMF) would be associated with a low incidence of acute and chronic GVHD in patients receiving a matched or single antigen mismatched HCT.

METHODS: This is a phase II study conducted at the University of Minnesota using a myeloablative regimen of either: (A) total body irradiation (TBI, total dose 1320 cGy, administered in 165 cGy fractions, twice a day from days -4 to -1) or (B) Busulfan 3.2mg/kg daily (cumulative AUC 19,000 – 21,000 μmol/min/L) plus fludarabine 40 mg/m² once daily days -5 to -2, followed by a GVHD prophylaxis regimen of PTCy (50mg/kg days +3 and +4), Tac and MMF (beginning day +5). The primary endpoint was cumulative incidence of chronic GVHD requiring systemic immunosuppression (IST) at 1-year post-transplant.

RESULTS: From March 2018 – May 2022, we enrolled 125 pediatric and adult patients with a median follow-up of 813 days. The incidence of chronic GVHD requiring systemic IST at 1 year was 5.5%. Grade II-IV acute GVHD occurred in 17.1%; Grade III-IV acute GVHD was 5.5%. Two-year overall survival (OS) was 73.7%, and 2-year graft-versus-host disease-free, relapse-free survival (GRFS) 52.2%. The 2-year cumulative incidence of non-relapse mortality was 10.2% and relapse was 39.1%. There was no statistically significant difference in survival outcomes between recipients of matched versus 7/8 donors.

CONCLUSION: Myeloablative HCT with PTCy/Tac/MMF results in an extremely low incidence of severe acute and chronic GVHD in well-matched allotransplantation.

PMID:37311510 | DOI:10.1016/j.jtct.2023.06.008

Am J Obstet Gynecol MFM. 2023 Jun 11:101049. doi: 10.1016/j.ajogmf.2023.101049. Online ahead of print.

ABSTRACT

OBJECTIVE: Tranexamic acid (TXA) is a cost-effective intervention for the prevention of postpartum hemorrhage (PPH) in women undergoing cesarean section but the evidence to support its use is conflicting. We conducted this meta-analysis to evaluate the efficacy and safety of TXA in low- and high-risk cesarean deliveries.

DATA SOURCES: We searched MEDLINE (via PubMed), Embase, the Cochrane Library, ClinicalTrials.gov, and WHO International Clinical Trials Registry Platform (ICTRP) portal from inception to April 2022 (updated October 2022 and February 2023) with no language restrictions. Additionally, grey literature sources were also explored.

STUDY ELIGIBILITY CRITERIA: All randomized controlled trials (RCTs) investigating the prophylactic use of intravenous TXA in addition to standard uterotonic agents in women undergoing cesarean deliveries as compared to placebo, standard treatment, or prostaglandins were included in this meta-analysis.

METHODS: We used the revised Cochrane “Risk of Bias” tool (RoB 2.0) to assess the quality of included RCTs. RevMan 5.4 was used to conduct all statistical analyses under a random-effects model.

RESULTS: We included 50 RCTs (6 in only high-risk patients and 2 with prostaglandins as the comparator) evaluating TXA in our meta-analysis. TXA reduced the risk of blood loss >1000 mL, mean total blood loss, and the need for blood transfusion in both low- and high-risk patients. TXA was associated with a beneficial effect in our secondary outcomes including decline in hemoglobin levels and the need for additional uterotonic agents. TXA increased the risk of non-thromboembolic adverse events but, based on limited data, did not increase the incidence of thromboembolic events. The administration of TXA before skin incision, but not after cord clamping, was associated with a large benefit. The quality of evidence was rated as low to very low for outcomes in the low-risk population and moderate for most outcomes in the high-risk subgroup.

CONCLUSIONS: TXA may reduce the risk of blood loss in cesarean deliveries with a higher benefit observed in high-risk patients but the lack of high-quality evidence precludes any strong conclusions. Additional studies, especially in the high-risk population and evaluating the timing of TXA administration, are needed to confirm or refute these findings.

PMID:37311484 | DOI:10.1016/j.ajogmf.2023.101049