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Nevin Manimala Statistics

Corrosion properties of low carbon CoCrMo and additively manufactured CoCr alloys for dental applications

Dent Mater. 2022 Jun 13:S0109-5641(22)00172-5. doi: 10.1016/j.dental.2022.06.021. Online ahead of print.

ABSTRACT

OBJECTIVES: Additive manufacturing (AM) is being applied to metallic biomaterials and dental alloys, including CoCrMo. CoCrMo mechanical properties and corrosion resistance are vital to the structural integrity of implants and dental appliances. The goal of this work is to assess the resistivity of AM cobalt chromium alloys by comparing them with traditional CoCrMo, regarding electrochemical properties resulting from microstructural and oxide film differences.

METHODS: In this work, selective laser melting (SLM), was used to manufacture CoCrMoW. The corrosion characteristics of AM alloy were compared to that of wrought LC CoCrMo (ASTM F-1537) in both phosphate buffered saline (PBS) and PBS with 10 mM H2O2 to simulate increased inflammatory conditions. Anodic polarization and electrochemical impedance spectroscopy (EIS) were performed.

RESULTS: Both alloys were substantially similar in corrosion behavior in both solutions. They exhibited changes with the different solutions. Polarization resistances were statistically lower (RpAM = 1.4 MΩcm2 (PBS) vs. 0.72 MΩcm2 (H2O2), RpLC = 1.86 MΩcm2 (PBS) vs. 0.55 MΩcm2 (H2O2)), and open circuit potentials (OCP’s) were statistically higher in 10 mM H2O2 for both alloys (0.20 V (in H2O2) vs. – 0.09 V in PBS). Chemistry variations were revealed by the corrosion tests indicating that wrought LC CoCrMo retained its casting-based chemical heterogeneity, while AM CoCrMoW had sub-cell structures within the solidified grains.

SIGNIFICANCE: As novel production methods like AM arise, it is necessary to understand any microstructural differences that may diminish the corrosion resistance properties. AM CoCrMoW alloys hold significant promise for use in dentistry where complex geometries are required.

PMID:35710472 | DOI:10.1016/j.dental.2022.06.021

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Nevin Manimala Statistics

A generalised smoothing approach for continuous, planar, inverse kinematics problems

J Biomech. 2022 May 30:111158. doi: 10.1016/j.jbiomech.2022.111158. Online ahead of print.

ABSTRACT

Bayesian methods have recently been proposed to solve inverse kinematics problems for marker based motion capture. The objective is to find the posterior distribution, a probabilistic summary of our knowledge and corresponding uncertainty about the model parameters such as joint angles, segment angles, segment translations, and marker positions. To date, Bayesian inverse kinematics models have focused on a frame by frame solution, which if repeatedly applied gives estimates that are discontinuous in time. We propose to overcome this limitation for continuous, planar inverse kinematics problems via the use of finite basis representations to model latent kinematic quantities as smooth, continuous functions. Our generalised smoothing approach is able to accurately approximate the solution to planar inverse kinematics problems defined by simple systems of ordinary differential equations in addition to considerably more complex systems such as a planar analysis of human gait. Improvements in accuracy are considerable with a decrease in average RMSE of 0.025 rad observed when estimating ankle joint angle for a randomly selected running stride with the proposed generalised smoothing approach compared to previous time-independent approaches. In addition, the generalised smoothing approach is able to effectively estimate kinematic parameters in the presence of missing data along with derivatives of kinematic quantities without the need for prior filtering or gap-filling of data.

PMID:35710465 | DOI:10.1016/j.jbiomech.2022.111158

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Nevin Manimala Statistics

Hormone therapy and the decreased risk of dementia in women with depression: a population-based cohort study

Alzheimers Res Ther. 2022 Jun 16;14(1):83. doi: 10.1186/s13195-022-01026-3.

ABSTRACT

BACKGROUND: The literature has shown depression to be associated with an increased risk of dementia. In addition, hormone therapy can be a responsive treatment option for a certain type of depression. In this study, we examined the association between hormone therapy, including lifetime oral contraceptive (OC) use, and hormone replacement therapy (HRT) after menopause with the occurrence of dementia among female patients with depression.

METHODS: The South Korean national claims data from January 1, 2005, to December 31, 2018, was used. Female subjects aged 40 years or older with depression were included in the analyses. Information on hormone therapy was identified from health examination data and followed up for the occurrence of dementia during the average follow-up period of 7.72 years.

RESULTS: Among 209,588 subjects, 23,555 were diagnosed with Alzheimer’s disease (AD) and 3023 with vascular dementia (VD). Lifetime OC usage was associated with a decreased risk of AD (OC use for < 1 year: HR, 0.92 [95% CI, 0.88-0.97]; OC use for ≥ 1 year: HR, 0.89 [95% CI, 0.84-0.94]), and HRT after menopause was associated with a decreased risk of AD (HRT for < 2 years: HR, 0.84 [95% CI, 0.79-0.89]; HRT for 2-5 years: HR, 0.80 [95% CI, 0.74-0.88]; and HRT for ≥ 5 years : HR, 0.78 [95% CI, 0.71-0.85]) and VD (HRT < 2 years: HR, 0.82 [95% CI, 0.71-0.96]; HRT for 2-5 years: HR, 0.81 [95% CI, 0.64-1.02]; and HRT for ≥ 5 years: HR, 0.61 [95% CI, 0.47-0.79]).

CONCLUSIONS: In this nationwide cohort study, lifetime OC use was associated with a decreased risk of AD, and HRT after menopause was associated with a decreased risk of AD and VD among female patients with depression. However, further studies are needed to establish causality.

PMID:35710453 | DOI:10.1186/s13195-022-01026-3

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Nevin Manimala Statistics

Effect of levosimendan infusion prior to left ventricular assist device implantation on right ventricular failure

J Cardiothorac Surg. 2022 Jun 16;17(1):158. doi: 10.1186/s13019-022-01915-6.

ABSTRACT

OBJECTIVE: Investigate the safety and efficacy of preoperative levosimendan in patients undergoing left ventricular assist device (LVAD) implantation.

METHODS: Consecutive patients who received LVADs (HeartMate-2, 3, HVAD) in a single tertiary medical center (2012-2018). INTERMACS profile 1 patients were excluded. The primary outcome was post-LVAD right ventricular failure (RVF) and inhospital mortality rates. The secondary outcomes included other clinical, echocardiographic and hemodynamic parameters at follow-up.

RESULTS: Final cohort consisted of 62 patients (40[65%] in the levosimendan group and 22[35%] in the no-levosimendan group). Post-operative RVF rate and inotrope or ventilation support time were similar in the levosimendan and no-levosimendan groups (7.5% vs. 13.6%; P = 0.43, median of 51 vs. 72 h; P = 0.41 and 24 vs. 27 h; P = 0.19, respectively). Length of hospitalization, both total and in the intensive care unit, was not statistically significant (median days of 13 vs. 16; P = 0.34, and 3 vs. 4; P = 0.44, respectively). Post-operative laboratory and echocardiographic parameters and in-hospital complication rate did not differ between the groups, despite worse baseline clinical parameters in the Levosimendan group. There was no significant difference in the in-hospital and long term mortality rate (2.5% vs. 4.5%; P > 0.999 and 10% vs. 27.3% respectively; P = 0.64).

CONCLUSIONS: Levosimendan infusion prior to LVAD implantation was safe and associated with comparable results without significant improved post-operative outcomes, including RVF.

PMID:35710438 | DOI:10.1186/s13019-022-01915-6

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Nevin Manimala Statistics

Spectrum of germline pathogenic variants using a targeted next generation sequencing panel and genotype-phenotype correlations in patients with suspected hereditary breast cancer at an academic medical centre in Pakistan

Hered Cancer Clin Pract. 2022 Jun 16;20(1):24. doi: 10.1186/s13053-022-00232-2.

ABSTRACT

BACKGROUND: Breast cancer is the most common malignancy in women, affecting over 1.5 million women every year, which accounts for the highest number of cancer-related deaths in women globally. Hereditary breast cancer (HBC), an important subset of breast cancer, accounts for 5-10% of total cases. However, in Low Middle-Income Countries (LMICs), the population-specific risk of HBC in different ethnicities and the correlation with certain clinical characteristics remain unexplored.

METHODS: Retrospective chart review of patients who visited the HBC clinic and proceeded with multi-gene panel testing from May 2017 to April 2020. Descriptive and inferential statistics were used to analyze clinical characteristics of patients. Fisher’s exact, Pearson’s chi-squared tests and Logistic regression analysis were used for categorical variables and Wilcoxon rank-sum test were used for quantitative variables. For comparison between two independent groups, Mann-Whitney test was performed. Results were considered significant at a p value of < 0.05.

RESULTS: Out of 273 patients, 22% tested positive, 37% had a VUS and 41% had a negative genetic test result. Fifty-five percent of the positive patients had pathogenic variants in either BRCA1 or BRCA2, while the remaining positive results were attributed to other genes. Patients with a positive result had a younger age at diagnosis compared to those having a VUS and a negative result; median age 37.5 years, IQR (Interquartile range) (31.5-48). Additionally, patients with triple negative breast cancer (TNBC) were almost 3 times more likely to have a positive result (OR = 2.79, CI = 1.42-5.48 p = 0.003). Of all patients with positive results, 25% of patients had a negative family history of breast and/or related cancers.

CONCLUSIONS: In our HBC clinic, we observed that our rate of positive results is comparable, yet at the higher end of the range which is reported in other populations. The importance of expanded, multi-gene panel testing is highlighted by the fact that almost half of the patients had pathogenic or likely pathogenic variants in genes other than BRCA1/2, and that our test positivity rate would have only been 12.8% if only BRCA1/2 testing was done. As the database expands and protocol-driven referrals are made across the country, our insight about the genetic architecture of HBC in our population will continue to increase.

PMID:35710434 | DOI:10.1186/s13053-022-00232-2

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Nevin Manimala Statistics

Impact of social environment on sexual behaviors of adolescent girls in 12 sub-Saharan African countries: a cross-sectional study

Reprod Health. 2022 Jun 16;19(1):139. doi: 10.1186/s12978-022-01448-0.

ABSTRACT

BACKGROUND: Early sexual debut among adolescent girls may result in teenage pregnancy and sexually transmitted diseases. In sub-Saharan Africa (SSA), pregnancy among adolescent girls may adversely impact the continuation of their education, general health status, and birth outcomes. However, few cross-national studies have examined the role that the social environment plays in adolescent girls’ sexual behaviors in SSA. In this study, we explored adolescent girls’ social environment and the impact on their sexual behaviors..

METHODS: The country selection was based on availability of Global School-Based Student Health Survey (GSHS) national data (2003-2015). The total analytic sample was 22,067 adolescent girls from 12 countries in SSA. Descriptive statistics were generated to determine the characteristics of adolescent girls and independent samples t-test analysis were performed to determine whether there were differences between the social environment and age of sexual debut and sexual partners. Logistic regression models were used to determine the association between adolescent girls’ social environment and sexual debut.

RESULTS: The study results showed variations across the 12 countries. Almost one in five (19.9%) adolescent girls reported to have ever engaged in sexual intercourse. Their mean age of sexual debut was 13.21 (13.04-13.37) years and mean number of sexual partners was 2.19 (2.08-2.29). We found that adolescent girls who reported not being connected with their parents were more likely to debut sex (aOR = 1.32, 95% CI, 1.14-1.53, p < 0.000). Parental monitoring was significantly associated with sexual debut but after controlling for the confounding variables (age, class grade and drug use), the association was no longer significantly positively associated. Adolescent girls who felt supported by their peers had a significantly higher number of sexual partners than those who did not feel supported by their peers.

CONCLUSION: The social environment of adolescent girls plays a very important role in sexual debut, age of sexual debut, and the number of sexual partners. Sexual health policies targeting adolescent girls are likely to achieve positive impacts if they focus on improving parental connectedness and peer support.

PMID:35710414 | DOI:10.1186/s12978-022-01448-0

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Nevin Manimala Statistics

Comparison between machine learning methods for mortality prediction for sepsis patients with different social determinants

BMC Med Inform Decis Mak. 2022 Jun 16;22(Suppl 2):156. doi: 10.1186/s12911-022-01871-0.

ABSTRACT

BACKGROUND: Sepsis is one of the most life-threatening circumstances for critically ill patients in the United States, while diagnosis of sepsis is challenging as a standardized criteria for sepsis identification is still under development. Disparities in social determinants of sepsis patients can interfere with the risk prediction performances using machine learning.

METHODS: We analyzed a cohort of critical care patients from the Medical Information Mart for Intensive Care (MIMIC)-III database. Disparities in social determinants, including race, sex, marital status, insurance types and languages, among patients identified by six available sepsis criteria were revealed by forest plots with 95% confidence intervals. Sepsis patients were then identified by the Sepsis-3 criteria. Sixteen machine learning classifiers were trained to predict in-hospital mortality for sepsis patients on a training set constructed by random selection. The performance was measured by area under the receiver operating characteristic curve (AUC). The performance of the trained model was tested on the entire randomly conducted test set and each sub-population built based on each of the following social determinants: race, sex, marital status, insurance type, and language. The fluctuations in performances were further examined by permutation tests.

RESULTS: We analyzed a total of 11,791 critical care patients from the MIMIC-III database. Within the population identified by each sepsis identification method, significant differences were observed among sub-populations regarding race, marital status, insurance type, and language. On the 5783 sepsis patients identified by the Sepsis-3 criteria statistically significant performance decreases for mortality prediction were observed when applying the trained machine learning model on Asian and Hispanic patients, as well as the Spanish-speaking patients. With pairwise comparison, we detected performance discrepancies in mortality prediction between Asian and White patients, Asians and patients of other races, as well as English-speaking and Spanish-speaking patients.

CONCLUSIONS: Disparities in proportions of patients identified by various sepsis criteria were detected among the different social determinant groups. The performances of mortality prediction for sepsis patients can be compromised when applying a universally trained model for each subpopulation. To achieve accurate diagnosis, a versatile diagnostic system for sepsis is needed to overcome the social determinant disparities of patients.

PMID:35710407 | DOI:10.1186/s12911-022-01871-0

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Nevin Manimala Statistics

Long-term postoperative outcomes of Roux-en-Y cholangiojejunostomy in patients with benign biliary stricture

BMC Surg. 2022 Jun 16;22(1):231. doi: 10.1186/s12893-022-01622-y.

ABSTRACT

BACKGROUND: Although there are common postoperative complications, Roux-en-Y cholangiojejunostomy is still broadly used as a standard surgical procedure for patients with biliary stricture. This study aimed to explore long-term risk factors of cholangiojejunostomy in patients with biliary stricture who underwent revisional cholangiojejunostomy.

METHODS: Clinical data of 61 patients with biliary stricture undergoing revisional cholangiojejunostomy were retrospectively analyzed. These patients were classified into two groups (patients with traumatic biliary stricture and non-traumatic biliary stricture). Postoperative complications and survival time were successfully followed up.

RESULTS: Among the patients, 34 underwent revisional cholangiojejunostomy due to traumatic biliary stricture, and 27 underwent revisional cholangiojejunostomy due to non-traumatic biliary surgery. Although there was no statistical difference in most clinical data between two groups, biliary dilation or not during the first surgery, cholelithiasis or not during the first surgery, long-term complications after first surgery, cholelithiasis or not during the second surgery, identifying abnormalities during the second surgery and long-term complications after second surgery were significantly different. All patients were successfully followed up and average follow-up time for patients with traumatic and non-traumatic biliary stricture was (88.44 ± 35.67) months and (69.48 ± 36.61) months respectively. Survival analysis indicated that there was no statistical difference in overall survival between two groups. Additionally, cox proportional hazard analysis demonstrated that first preoperative bilirubin level, short-term complication after first surgery and identifying abnormalities during the second surgery were independent risk factors that may have significant effects on patients’ overall survival and long-term prognosis after cholangiojejunostomy. Among the intraoperative abnormal findings, residual lesions after the first operation had significant effects on the patients overall survival in the earlier stage. Relatively, anastomotic stoma stricture and biliary output loop problems had obvious effects on patients’ overall survival at later stages.

CONCLUSION: First preoperative bilirubin level, short-term complication after first surgery and abnormal findings during the second surgery were independent risk factors of revisional cholangiojejunostomy, which may affect patients’ long-term survival. Therefore, surgeons should minimize incidence of postoperative complications through fully evaluating optimal operative time and standardizing surgical procedures.

PMID:35710403 | DOI:10.1186/s12893-022-01622-y

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Nevin Manimala Statistics

Mining comorbidities of opioid use disorder from FDA adverse event reporting system and patient electronic health records

BMC Med Inform Decis Mak. 2022 Jun 16;22(Suppl 2):155. doi: 10.1186/s12911-022-01869-8.

ABSTRACT

BACKGROUND: Opioid use disorder (OUD) has become an urgent health problem. People with OUD often experience comorbid medical conditions. Systematical approaches to identifying co-occurring conditions of OUD can facilitate a deeper understanding of OUD mechanisms and drug discovery. This study presents an integrated approach combining data mining, network construction and ranking, and hypothesis-driven case-control studies using patient electronic health records (EHRs).

METHODS: First, we mined comorbidities from the US Food and Drug Administration Adverse Event Reporting System (FAERS) of 12 million unique case reports using frequent pattern-growth algorithm. The performance of OUD comorbidity mining was measured by precision and recall using manually curated known OUD comorbidities. We then constructed a disease comorbidity network using mined association rules and further prioritized OUD comorbidities. Last, novel OUD comorbidities were independently tested using EHRs of 75 million unique patients.

RESULTS: The OUD comorbidities from association rules mining achieves a precision of 38.7% and a recall of 78.2 Based on the mined rules, the global DCN was constructed with 1916 nodes and 32,175 edges. The network-based OUD ranking result shows that 43 of 55 known OUD comorbidities were in the first decile with a precision of 78.2%. Hypothyroidism and type 2 diabetes were two top-ranked novel OUD comorbidities identified by data mining and network ranking algorithms. Based on EHR-based case-control studies, we showed that patients with OUD had significantly increased risk for hyperthyroidism (AOR = 1.46, 95% CI 1.43-1.49, p value < 0.001), hypothyroidism (AOR = 1.45, 95% CI 1.42-1.48, p value < 0.001), type 2-diabetes (AOR = 1.28, 95% CI 1.26-1.29, p value < 0.001), compared with individuals without OUD.

CONCLUSION: Our study developed an integrated approach for identifying and validating novel OUD comorbidities from health records of 87 million unique patients (12 million for discovery and 75 million for validation), which can offer new opportunities for OUD mechanism understanding, drug discovery, and multi-component service delivery for co-occurring medical conditions among patients with OUD.

PMID:35710401 | DOI:10.1186/s12911-022-01869-8

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Nevin Manimala Statistics

The clinical effectiveness and cost-effectiveness of a ‘stepping into day treatment’ approach versus inpatient treatment as usual for anorexia nervosa in adult specialist eating disorder services (DAISIES trial): a study protocol of a randomised controlled multi-centre open-label parallel group non-inferiority trial

Trials. 2022 Jun 16;23(1):500. doi: 10.1186/s13063-022-06386-7.

ABSTRACT

BACKGROUND: Anorexia nervosa (AN) is a serious and disabling mental disorder with a high disease burden. In a proportion of cases, intensive hospital-based treatments, i.e. inpatient or day patient treatment, are required, with day patient treatment often being used as a ‘step-down’ treatment after a period of inpatient treatment. Demand for such treatment approaches has seen a sharp rise. Despite this, the relative merits of these approaches for patients, their families, and the NHS and wider society are relatively unknown. This paper describes the rationale for, and protocol of, a two-arm multi-centre open-label parallel group non-inferiority randomised controlled trial, evaluating the effectiveness and cost-effectiveness of these two intensive treatments for adults with severe AN: inpatient treatment as usual and a stepped care day patient approach (the combination of day patient treatment with the option of initial inpatient treatment for medical stabilisation). The main aim of this trial is to establish whether, in adults with severe AN, a stepped care day patient approach is non-inferior to inpatient treatment as usual in relation to improving body mass index (BMI) at 12 months post-randomisation.

METHODS: 386 patients with a Diagnostic and Statistical Manual 5th edition diagnosis of severe AN or related disorder, with a BMI of ≤16 kg/m2 and in need of intensive treatment will be randomly allocated to either inpatient treatment as usual or a stepped care day patient approach. Patients in both groups will receive treatment until they reach a healthy weight or get as close to this point as possible. Assessments will be conducted at baseline (prior to randomisation), and at 6 and 12 months post-randomisation, with additional monthly symptom monitoring. The primary outcome will be BMI at the 12-month post-randomisation assessment. Other outcomes will include psychosocial adjustment; treatment motivation, expectations and experiences; cost-effectiveness; and carer burden.

DISCUSSION: The results of this study will provide a rigorous evaluation of two intensive treatment approaches which will inform future national and international treatment guidelines and service provision.

TRIAL REGISTRATION: ISRCTN ISRCTN10166784 . Registered 28 February 2020. ISRCTN is a primary registry of the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) network and includes all items from the WHO Trial Registration Data Set.

PMID:35710394 | DOI:10.1186/s13063-022-06386-7