Category: Statistics

Sensors (Basel). 2023 Feb 2;23(3):1615. doi: 10.3390/s23031615.

ABSTRACT

Heart rate variability (HRV) indexes are becoming useful in various applications, from better diagnosis and prevention of diseases to predicting stress levels. Typically, HRV indexes are retrieved from the heart’s electrical activity collected with an electrocardiographic signal (ECG). Heart-induced mechanical signals recorded from the body’s surface can be utilized to record the mechanical activity of the heart and, in turn, extract HRV indexes from interbeat intervals (IBIs). Among others, accelerometers and gyroscopes can be used to register IBIs from precordial accelerations and chest wall angular velocities. However, unlike electrical signals, the morphology of mechanical ones is strongly affected by body posture. In this paper, we investigated the feasibility of estimating the most common linear and non-linear HRV indexes from accelerometer and gyroscope data collected with a wearable skin-interfaced Inertial Measurement Unit (IMU) positioned at the xiphoid level. Data were collected from 21 healthy volunteers assuming two common postures (i.e., seated and lying). Results show that using the gyroscope signal in the lying posture allows accurate results in estimating IBIs, thus allowing extracting of linear and non-linear HRV parameters that are not statistically significantly different from those extracted from reference ECG.

PMID:36772656 | DOI:10.3390/s23031615

Sensors (Basel). 2023 Feb 1;23(3):1603. doi: 10.3390/s23031603.

ABSTRACT

The study of brain connectivity plays an important role in understanding the functional organizations of the brain. It also helps to identify connectivity signatures that can be used for evaluating neural disorders and monitoring treatment efficacy. In this work, age-related changes in brain connectivity are studied to obtain aging signatures based on various modeling techniques. These include an energy-based machine learning technique to identify brain network interaction differences between two age groups with a large (30 years) age gap between them. Disconnectivity graphs and activation maps of the seven prominent resting-state networks (RSN) were obtained from functional MRI data of old and young adult subjects. Two-sample t-tests were performed on the local minimums with Bonferroni correction to control the family-wise error rate. These local minimums are connectivity states showing not only which brain regions but also how strong they are working together. They work as aging signatures that can be used to differentiate young and old groups. We found that the attention network’s connectivity signature is a state with all the regions working together and young subjects have a stronger average connectivity among these regions. We have also found a common pattern between young and old subjects where the left and right brain regions of the frontal network are sometimes working separately instead of together. In summary, in this work, we combined machine learning and statistical approaches to extract connectivity signatures, which can be utilized to distinguish aging brains and monitor possible treatment efficacy.

PMID:36772649 | DOI:10.3390/s23031603

Sensors (Basel). 2023 Feb 1;23(3):1566. doi: 10.3390/s23031566.

ABSTRACT

Signal acquisition is a crucial step in Global Navigation Satellite System (GNSS) receivers, which is typically solved by maximizing the so-called Cross-Ambiguity Function (CAF) as a hypothesis testing problem. This article proposes to use deep learning models to perform such acquisition, whereby the CAF is fed to a data-driven classifier that outputs binary class posteriors. The class posteriors are used to compute a Bayesian hypothesis test to statistically decide the presence or absence of a GNSS signal. The versatility and computational affordability of the proposed method are addressed by splitting the CAF into smaller overlapping sections, which are fed to a bank of parallel classifiers whose probabilistic results are optimally fused to provide a so-called probability ratio map from which acquisition is decided. Additionally, the article shows how noncoherent integration schemes are enabled through optimal data fusion, with the goal of increasing the resulting classifier accuracy. The article provides simulation results showing that the proposed data-driven method outperforms current CAF maximization strategies, enabling enhanced acquisition at medium-to-high carrier-to-noise density ratios.

PMID:36772605 | DOI:10.3390/s23031566

BMC Public Health. 2023 Feb 10;23(1):303. doi: 10.1186/s12889-023-15185-x.

ABSTRACT

BACKGROUND: Suicide among the elderly has become a global public health concern. This study was carried out to determine the trend of completed suicide rates according to age, sex, and ethnicity and the suicidal methods among the elderly in Malaysia.

METHODS: All suicide-related deaths in elderly aged 60 years and above from the Year 1995 to 2020 reported to the National Registration Department (NRD) were analyzed. Causes of death for suicide were coded based on the International Statistical Classification of Diseases and Related Health Problems, 10th Revision (ICD-10). The completed suicide rate was calculated by dividing the completed suicide number by the total elderly population for the respective year.

RESULTS: Overall, the analysis of 1,600 suicide-related deaths was investigated over 26 years. Male was seen to be correlated with higher suicidal risk, with a male-female relative risk (RR) = 1.89 (95%CI:1.46,2.45). The risk of suicide was also found to be significantly higher for those aged 60 to 74 years old and Chinese, with RR = 4.26 (95%CI:2.94, 6.18) and RR = 5.81 (95%CI: 3.70, 9.12), respectively. Hanging was found to be a statistically significant suicide method (IRR:4.76, 95%CI:2.34,9.65) as compared to pesticide poisoning. The completed suicide rate was fluctuating over the years.

CONCLUSIONS: In conclusion, it is believed that Malaysia’s elderly suicide rate has reached an alarmingly high incidence. By identifying the crucial criteria of sociodemographic factors, the government and responsible agencies have the essential and additional information to put together a more effective strategy and approach to overcome the issue in the future.

PMID:36765292 | DOI:10.1186/s12889-023-15185-x

BMC Musculoskelet Disord. 2023 Feb 10;24(1):113. doi: 10.1186/s12891-023-06202-6.

ABSTRACT

BACKGROUND: Bone mineral density (BMD) alterations in response to multivitamin exposure were rarely studied. Our study assessed the association of coexposure to six types of vitamins (i.e., vitamins B12, B9, C, D, A and E) with BMD measurements in adults in the US.

METHODS: Data were collected from participants aged ≥ 20 years (n = 2757) in the U.S. National Health and Nutrition Examination Surveys (NHANES) from 2005 to 2006. Multiple linear regression, restricted cubic splines, principal component analysis (PCA) and weighted quantile sum (WQS) regression were performed for statistical analysis.

RESULTS: The circulating levels of vitamins B12 and C were positively associated with BMDs, and an inverted L-shaped exposure relationship was observed between serum vitamin C and BMDs. PCA identified two principal components: one for ‘water-soluble vitamins’, including vitamins B12, B9 and C, and one for ‘fat-soluble vitamins’, including vitamins A, D and E. The former was positively associated with total femur (β = 0.009, 95%CI: 0.004, 0.015) and femoral neck (β = 0.007, 95%CI: 0.002, 0.013) BMDs, and the latter was negatively associated with BMDs with non-statistical significance. The WQS index constructed for the six vitamins was significantly related to total femur (β = 0.010, 95%CI: 0.001, 0.018) and femoral neck (β = 0.008, 95%CI: 0.001, 0.015) BMDs, and vitamins B12 and C weighted the most. The WQS index was inversely related to BMDs with non-statistical significance, and vitamins E and A weighted the most.

CONCLUSION: Our findings suggested a positive association between water-soluble vitamin coexposure and BMD, and the association was mainly driven by vitamins B12 and C. Negative association between fat-soluble vitamin coexposure and BMD was indicated, mainly driven by vitamins E and A. An inverted L-shaped exposure relationship was found between vitamin C and BMD.

PMID:36765290 | DOI:10.1186/s12891-023-06202-6

BMC Neurol. 2023 Feb 10;23(1):64. doi: 10.1186/s12883-023-03101-0.

ABSTRACT

BACKGROUND: Multiple sclerosis (MS) has two pathophysiological processes, one inflammatory and the other degenerative. We investigated the relationship between active lesions on magnetic resonance imaging showing the inflammatory phase in MS patients and serum parameters that can be used as inflammatory biomarkers. Thus, we aim to detect the inflammatory period in clinical and radiological follow-up and to reveal the period in which disease-modifying treatments are effective with serum parameters.

METHODS: One hundred eighty-six MS patients presented to our hospital between January 2016 and November 2021 and 94 age- and sex-matched healthy volunteers were recruited for our study. While 99 patients had active lesions on magnetic resonance imaging, 87 patients did not have any active lesions. Neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), and monocyte/lymphocyte ratio (MLR) were determined. The SII (systemic immune inflammatory index) value was calculated according to the platelet X neutrophil/lymphocyte ratio formula.

RESULTS: NLR, MLR, PLR and SII values were found to be statistically significantly higher in MS patients than in the control group. The NLR, MLR, PLR and SII were higher in the active group with gadolonium than in the group without active lesions. In addition, the cutoff values that we can use to determine the presence of active lesions were 1.53, 0.18, 117.15, and 434.45 for NLR, MLR PLR and SII, respectively.

CONCLUSIONS: We found that all parameters correlated with radiological activity. In addition, we showed that we can detect the inflammatory period with high sensitivity and specificity with the cutoff value used for SII and PLR. Among these easily accessible and inexpensive evaluations, we concluded that SII, including the values in the PLR formula, can come to the fore.

PMID:36765289 | DOI:10.1186/s12883-023-03101-0

BMC Anesthesiol. 2023 Feb 10;23(1):51. doi: 10.1186/s12871-023-01983-8.

ABSTRACT

BACKGROUND: Esmolol as one treatment of sepsis induced cardiomyopathy (SIC) is still controversial. The objective of this study is to evaluate cardiac function after reducing heart rate by Esmolol in patients with SIC using speck-tracking echocardiography.

METHODS: This study was a single-center, prospective, and randomized controlled study. A total of 100 SIC patients with a heart rate more than 100/min, admitted to the Intensive Care Department of Tianjin Third Central Hospital from March 1, 2020 to September 30, 2021, were selected as the research subjects. They were randomly divided into the Esmolol group (Group E) and the conventional treatment group (Group C), each with 50 cases. The target heart rate of patients in Group E was controlled between 80/min and 100/min. Speck-tracking echocardiography (STE) and pulse indicating continuous cardiac output monitoring (PICCO) were performed in both groups at 1 h, 24 h, 48 h, 72 h, 96 h and 7 d after admission, with data concerning left ventricular global longitudinal strain (GLS), left ventricular ejection fraction (LVEF) and global ejection fraction (GEF), left ventricular systolic force index (dP/dtmx) were obtained, respectively. Hemodynamics and other safety indicators were monitored throughout the whole process. These subjects were followed up to 90 d, with their mortality recorded at Day 28 and Day 90, respectively. Statistical analyses were performed using SPSS version 21.

RESULTS: With 24 h of Esmolol, all patients in Group E achieved the target heart rate, and there was no deterioration of GLS, or adverse events. However, compared with those in Group C, their GLS, GEF and dP/dtmx were increased, and the difference was statistically significant (P > 0.05). Compared with patients in Group C, those in Group E had lower short-term mortality, and logistic regression analysis also suggested that Esmolol improved patient outcomes.

CONCLUSION: In SIC patients, the application of Esmolol to lower heart rate decreased their short-term mortality while not making any impairment on the myocardial contractility.

TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR2100047513. Registered June 20, 2021- Retrospectively registered, http://www.chictr.org.cn/index.aspx . The study protocol followed the CONSORT guidelines. The study protocol was performed in the relevant guidelines.

PMID:36765286 | DOI:10.1186/s12871-023-01983-8

BMC Cardiovasc Disord. 2023 Feb 10;23(1):81. doi: 10.1186/s12872-022-02990-2.

ABSTRACT

BACKGROUND: Blunt cardiac injury (BCI) has a variety of symptoms that may be a potentially life-threatening injury that can lead to death. Depending on the diagnosis of BCI, treatment direction and length of stay may vary. In addition, the utility of other diagnostic tests for cardiac disease as diagnostic tools for BCI remain unclear. The purpose of this study was to investigate the competence of N-terminal pro-B-type natriuretic peptide (NT pro-BNP) and cardiac index (C.I) as adjunctive diagnostic tools for BCI.

METHODS: From January 2018 to March 2020, severe trauma patients with sternum fracture who were admitted to the traumatic intensive care unit (TICU) were included this study. Patients with sternum fracture, 18 years of age or older, and with an injury severity score > 16 who required intensive care were included. Invasive measurement for the analysis of the pulse contour for C.I monitoring and intravenous blood sampling for NT pro-BNP measurement were performed. Sampling and 12-lead electrocardiogram were performed at different time points as follows: immediately after TICU admission and at 24 h and 48 h after trauma.

RESULTS: Among 103; 33 patients with factors that could affect NT pro-BNP were excluded; therefore, 63 patients were included in this study. According to the American Association for the Surgery of Trauma Cardiac Injury Scale, 33 patients were diagnosed with non-BCI, and 30 patients constituted with BCI. The median ages of the patients were 58 (52-69), and 60 (45-69) years in the non-BCI and BCI groups, respectively (p = 0.77). The median NT pro-BNP values were higher in the BCI group on admission, hospital day (HD) 2, and HD 3, however, no statistical difference was observed (125 (49-245) vs. 130 (47-428) pg/mL, p = 0.08, 124 (68-224) vs. 187 (55-519) pg/mL, p = 0.09, and 121(59-225) vs. 133 (56-600) pg/mL, p = 0.17, respectively). On the contrary, significantly lower values were observed in the median C.I measurement on admission and HD 3 in the BCI group (3.2 (2.8-3.5) vs. 2.6 (2.3-3.5) L/min/m², p < 0.01 and 3.2 (3.1-3.9) vs. 2.9 (2.4-3.2) L/min/m², p < 0.01, respectively); however, no significant difference was observed on HD 2 (3.4 (3.0-3.7) vs. 2.6 (2.4-3.4) L/min/m², p = 0.17), Furthermore, The median lactate levels in the BCI group upon admission, HD 2, and HD 3 were significantly higher than those in the non-BCI group (1.8 (1.1-2.6) vs. 3.1 (2.1-4.4) mmol/L, p < 0.01; 1.3 (0.8-2.3) vs. 3.0 (2.2-4.7) mmol/L, p < 0.01; and 1.5 (0.9-1.5) vs. 2.2 (1.3-3.7) mmol/L, p < 0.01, respectively).

CONCLUSION: Consecutive values of NT pro-BNP and C.I show no correlation with ECG-based BCI diagnosis. However, lactate level measurement may help in the early recognition of BCI as an adjunctive tool. It should be noted that this is a hypothesis-generating study for BCI diagnosis. Further studies should be conducted in larger populations with a prospective approach.

PMID:36765285 | DOI:10.1186/s12872-022-02990-2

BMC Cancer. 2023 Feb 10;23(1):138. doi: 10.1186/s12885-023-10559-1.

ABSTRACT

BACKGROUND: Rearranged during transfection (RET) tyrosine kinase signaling has been previously implicated in endocrine resistant breast cancer, however the mechanism by which this signaling cascade promotes resistance is currently not well described. We recently reported that glial cell-derived neurotrophic factor (GDNF)-RET signaling appears to promote a positive feedback loop with the transcription factor early growth response 1 (EGR1). Here we investigate the mechanism behind this feedback loop and test the hypothesis that GDNF-RET signaling forms a regulatory loop with EGR1 to upregulate cyclin D1 (CCND1) transcription, leading to cell cycle progression and tamoxifen resistance.

METHODS: To gain a better understanding of the GDNF-RET-EGR1 resistance mechanism, we studied the GDNF-EGR1 positive feedback loop and the role of GDNF and EGR1 in endocrine resistance by modulating their transcription levels using CRISPR-dCAS9 in tamoxifen sensitive (TamS) and tamoxifen resistant (TamR) MCF-7 cells. Additionally, we performed kinetic studies using recombinant GDNF (rGDNF) treatment of TamS cells. Finally, we performed cell proliferation assays using rGDNF, tamoxifen (TAM), and Palbociclib treatments in TamS cells. Statistical significance for qPCR and chromatin immunoprecipitation (ChIP)-qPCR experiments were determined using a student’s paired t-test and statistical significance for the cell viability assay was a one-way ANOVA.

RESULTS: GDNF-RET signaling formed a positive feedback loop with EGR1 and also downregulated estrogen receptor 1 (ESR1) transcription. Upregulation of GDNF and EGR1 promoted tamoxifen resistance in TamS cells and downregulation of GDNF promoted tamoxifen sensitivity in TamR cells. Additionally, we show that rGDNF treatment activated GDNF-RET signaling in TamS cells, leading to recruitment of phospho-ELK-1 to the EGR1 promoter, upregulation of EGR1 mRNA and protein, binding of EGR1 to the GDNF and CCND1 promoters, increased GDNF protein expression, and subsequent upregulation of CCND1 mRNA levels. We also show that inhibition of cyclin D1 with Palbociclib, in the presence of rGDNF, decreases cell proliferation and resensitizes cells to TAM.

CONCLUSION: Outcomes from these studies support the hypotheses that GDNF-RET signaling forms a positive feedback loop with the transcription factor EGR1, and that GDNF-RET-EGR1 signaling promotes endocrine resistance via signaling to cyclin D1. Inhibition of components of this signaling pathway could lead to therapeutic insights into the treatment of endocrine resistant breast cancer.

PMID:36765275 | DOI:10.1186/s12885-023-10559-1

BMC Cardiovasc Disord. 2023 Feb 10;23(1):80. doi: 10.1186/s12872-023-03072-7.

ABSTRACT

BACKGROUND: The home treatment of elderly patients with chronic heart failure (CHF) is often accompanied by malnutrition, which increases the risk of re-hospitalisation and affects the prognosis. Therefore, how to effectively improve the nutritional self-management of patients is a current focus of medical research. This study aims to test the effect of home-based nutritional intervention method on improving the nutritional status of elderly patients with CHF.

METHODS: A total of 90 hospitalised elderly patients with CHF were randomly divided into the experimental group (n = 45) and the control group (n = 45). The patients in both groups were given standardised drug therapy and their nutritional status was evaluated using a body composition analyser prior to discharge (protein, body fat percentage, visceral fat area, skeletal muscle, upper arm muscle circumference, left lower limb and right lower limb muscle mass), with the cardiopulmonary function evaluated using a six-minute walk test and the metabolic equivalents method. The control group was given general nutrition education and routine dietary guidance from cardiac rehabilitation nurses, while the experimental group was given an individualised nutrition prescription by dietitians based on the evaluation results, according to which one-to-one food exchange dietary intervention training was given until the patients mastered the process.

RESULTS: The nutritional indexes at the end of the study were significantly higher in the experimental group than in the control group and were higher than those before the intervention (P < 0.05). The muscle circumference of the upper arm, the muscle mass of the left lower limb and the right lower limb had no statistical significance following the intervention compared to the control group and before the intervention (P > 0.05). The cardiopulmonary function indexes were significantly better in the experimental group at the end of the study than before the intervention and were better than those in the control group, with statistically significant differences (P < 0.05), while no significant changes were observed in the control group before and after the intervention (P > 0.05).

CONCLUSION: The home-based nutritional intervention method of food exchange portions can effectively improve the nutritional status of elderly patients with CHF, with the distribution of visceral fat more reasonable and the cardiopulmonary function and exercise endurance improved.

PMID:36765270 | DOI:10.1186/s12872-023-03072-7