Tag: statistics

Mol Cell Biochem. 2022 Nov 9. doi: 10.1007/s11010-022-04605-y. Online ahead of print.

ABSTRACT

Premature ventricular contractions (PVCs) are the most frequent ventricular arrhythmias in the overall population. PVCs are known to acutely enhance contractility by the post-extrasystolic potentiation phenomenon, but over time persistent PVCs promote PVC-induced cardiomyopathy (PVC-CM), characterized by a reduction of the left ventricular (LV) ejection fraction. Ca²⁺ cycling in myocytes commands muscle contraction and in this process, SERCA2 leads the Ca²⁺ reuptake into the sarcoplasmic reticulum (SR) shaping cytosolic Ca²⁺ signal decay and muscle relaxation. Altered Ca²⁺ reuptake can contribute to the contractile dysfunction observed in PVC-CM. To better understand Ca²⁺ handling using our PVC-CM model (canines with 50% PVC burden for 12 weeks), SR-Ca²⁺ reuptake was investigated by measuring Ca²⁺ dynamics and analyzing protein expression. Kinetic analysis of Ca²⁺ reuptake in electrically paced myocytes showed a ~ 21 ms delay in PVC-CM compared to Sham in intact isolated myocytes, along with a ~ 13% reduction in SERCA2 activity assessed in permeabilized myocytes. Although these trends were not statistically significant between groups using hierarchical statistics, relaxation of myocytes following contraction was significantly slower in PVC-CM vs Sham myocytes. Western blot analyses indicate a 22% reduction in SERCA2 expression, a 23% increase in phospholamban (PLN) expression, and a 50% reduction in PLN phosphorylation in PVC-CM samples vs Sham. Computational analysis simulating a 20% decrease in SR-Ca²⁺ reuptake resulted in a ~ 22 ms delay in Ca²⁺ signal decay, consistent with the experimental result described above. In conclusion, SERCA2 and PLB alterations described above have a modest contribution to functional adaptations observed in PVC-CM.

PMID:36350464 | DOI:10.1007/s11010-022-04605-y

Psychogeriatrics. 2022 Nov 9. doi: 10.1111/psyg.12909. Online ahead of print.

ABSTRACT

BACKGROUND: Geriatric cognitive impairment often occurs in conjunction with depressive symptoms. This study focuses on categorising the Chinese elderly with such co-occurring symptoms into homogeneous groups using latent profile analysis (LPA), a person-centred statistical approach.

METHODS: Information on cognitive function and depressive states of the elderly was extracted from the China Health and Retirement Longitudinal Study. The underlying characteristics were identified by LPA, and based on those findings, differences in demographic characteristics of different subgroups were explored by chi-squared test and analysis of variance.

RESULTS: A total of 6710 Chinese elderly who met the inclusion criteria were selected from the dataset. Four subgroups were identified among this sample by LPA, based on cognitive function associated with depressive symptoms, and named in this study as follows: mild cognitive impairment (n = 3747, 55.84%), moderate cognitive impairment (n = 1306, 19.46%), mild cognitive impairment combined with depressive symptoms (n = 1114, 16.6%), and moderate cognitive impairment combined with depression (n = 543, 8.09%). Age, gender, marital status, and educational level were all significantly different across subgroups (P < 0.001); religious belief and pension mode, however, were not (P > 0.05).

CONCLUSIONS: In the present study, four subgroups of cognitive function combined with depressive symptoms were found in Chinese elderly individuals, and differences in demographic factors were noted between the subgroups. In clinical practise, these findings could help clinical workers identify patients accurately and consider the demographic features of each subgroup when designing medical treatment, care, and rehabilitation programmes for those with cognitive impairment and concomitant depressive symptoms.

PMID:36349873 | DOI:10.1111/psyg.12909

Transfus Med. 2022 Nov 9. doi: 10.1111/tme.12935. Online ahead of print.

ABSTRACT

BACKGROUND: Hepatitis C virus (HCV) can be transmitted by blood transfusion. The aim of this meta-analysis is to estimate the anti-HCV reactive rate and to define the demographic characteristics of blood donors who have potential threats to blood safety in mainland China for nearly 30 years, in order to provide a safe reference for blood transfusion and corresponding guidance for policymakers to increase blood safety.

MATERIALS AND METHODS: Literature reporting the anti-HCV screening reactive rate in Chinese blood donors was identified by systematic searching of four electronic databases from 1991 to 2017. The Preferred Reporting of Items for Systematic Reviews and Meta-Analyses guidelines were strictly followed, and data manipulation and statistical analysis were performed by Stata 15.0.

RESULTS: Our results showed that the post-donation anti-HCV reactive rate was 0.53% (95% confidence interval [CI], 0.51%-0.55%) with a significant variation from 1.58% (95% CI, 1.13%-2.03%) before 1998 to 0.51% (95% CI, 0.48%-0.53%) after 1998 when the Blood Donation Law was implemented in China. In addition, anti-HCV screening reactive rate for family or replacement donors was significantly higher than that in individual voluntary blood donors.

CONCLUSION: Our results indicated that blood centres in China should convert more eligible first-time donors into repeat donors and turn the ‘real family or replacement donors’ into individual voluntary blood donors to reduce the risk of transfusion-transmitted HCV. In the meantime, large surveys should be carried out among volunteer donors from high-risk populations.

PMID:36349871 | DOI:10.1111/tme.12935

Tijdschr Psychiatr. 2022;64(9):604-607.

ABSTRACT

BACKGROUND: In 2018 Jellinek became a smoke free institution. By implementing &lsquo;Jellinek Smoke free&rsquo; in all locations (15), a policy has been implemented to facilitate smoking cessation in clients with a comorbid tobacco use disorder seeking treatment for substance use disorders at Jellinek.

AIM: To investigate whether the implementation of the new policy impacted smoking behaviour of clients in treatment for substance use disorders at Jellinek.

METHOD: Based on data from anonymized client files, changes in smoking behaviour (cessation or reduction) were analysed for clients with other addictions who started treatment in 2016 versus clients who started in 2019 – after the implementation of the new smoke free policy. Comparative analyses were conducted on the population as a whole, per type of treatment (outpatient care, residential care, Minnesota, outreaching care) as well as per type of smoker (light, moderate, heavy).

RESULTS: In the client population as a whole, significantly more people stopped smoking in 2019 (22%) in comparison to 2016 (16%) and there was a trend toward statistical significance with regard to reduction. When a cessation period was part of treatment, significantly more clients stopped and decreased the number of cigarettes a day. Moreover, light and moderate smokers (&le; 20 cigarettes a day) stopped and reduced significantly more in 2019 (32%) than in 2016 (23%). In outpatient care, outreaching care and with heavy smokers (&gt; 20 cigarettes a day), there was no significant difference in percentage of cessation and reduction between 2016 and 2019.

CONCLUSION: After implementing Jellinek Smoke free, significant changes in smoking behaviour occurred in the client population as a whole with a comorbid tobacco use disorder, in treatments where a cessation period was part of treatment as well as with light and moderate smokers.

PMID:36349857

Tijdschr Psychiatr. 2022;64(9):558-565.

ABSTRACT

BACKGROUND: Psychiatric disorders are associated with a more severe course of COVID-19. COVID-19 can also lead to psychiatric symptoms.

AIM: To gain insight into vulnerabilities and protective factors for the course of COVID-19 in a Dutch (neuro)psychiatric population.

METHOD: Patients were divided into three groups: patients with pre-existent mental disorders without and with new (neuro)psychiatric symptoms (NPS) during COVID-19 and patients without pre-existent mental disorders who developed de novo NPS during COVID-19. We summarize the characteristics of each group and compare the subgroups with inferential statistics.

RESULTS: 186 patients were included in the case register. Patients with NPS showed a more severe course of COVID-19. Mortality in patients with NPS was higher in patients with pre-existent mental disorders compared to patients without pre-existent mental disorders. The most frequently reported de novo psychiatric symptoms during COVID-19 were delirium (46-70%), anxiety (53-54%) and insomnia (18-42%).

CONCLUSION: NPS might be an expression of a more severe COVID-19 episode. In patients who developed NPS during COVID-19 we found evidence for a higher mortality risk in patients with pre-existent mental disorders. Extra vigilance for neuropsychiatric symptoms during COVID-19 is warranted.

PMID:36349850

Soft Matter. 2022 Nov 9. doi: 10.1039/d2sm01093c. Online ahead of print.

ABSTRACT

The two-state stochastic phenomenon is observed in various systems and is attracting more interest, and it can be described by the two-state random walk (TSRW) model. The TSRW model is a typical two-state renewal process alternating between the continuous-time random walk state and the Lévy walk state, in both of which the sojourn time distributions follow a power law. In this paper, by discussing the statistical properties and calculating the ensemble averaged and time averaged mean squared displacement, the ergodic property and the ultimate diffusive behavior of the aging TSRW is studied. Results reveal that because of the two-state intermittent feature, ergodicity and nonergodicity can coexist in the aging TSRW, which behave as the time scalings of the time averages and ensemble averages not being identically equal. In addition, we find that the unique state occupation mechanism caused by the diverging mean of the sojourn times of one state, determines the aging TSRW’s ultimate diffusive behavior at extremely large timescales, i.e., instead of the term with the larger diffusion exponent, the diffusion is surprisingly characterized by the term with the smaller one, which is distinctly different from previous conclusions and known results. At last, we note that the Lévy walk with rests model which also displays aging and ergodicity breaking, can be generalized by the TSRW model.

PMID:36349834 | DOI:10.1039/d2sm01093c

J Magn Reson Imaging. 2022 Nov 9. doi: 10.1002/jmri.28522. Online ahead of print.

ABSTRACT

BACKGROUND: Little is known about internal carotid artery (ICA) hemodynamics in patients with moyamoya angiopathy (MMA) and its role in cerebrovascular events.

PURPOSE: To characterize ICA hemodynamics in MMA patients by 4D flow MRI and investigate its relationship with cerebrovascular events.

STUDY TYPE: Prospective.

SUBJECTS: Seventy MMA patients (50 years old ± 9, 30 males).

FIELD STRENGTH/SEQUENCE: Time-resolved three-directional velocity encoded fast field echo sequence (4D flow) MRI, T1-weighted fast field echo sequence, T2 weighted turbo spin echo sequence, diffusion weighted echo planar imaging; T2-weighted fluid-attenuated inversion recovery turbo spin echo sequence, susceptibility weighted fast field echo sequence, and time-of-flight MR angiography fast field echo sequence at 3.0T.

ASSESSMENT: ICA hemodynamics (maximum and average velocity [V_max , V_avg ], average blood flow [Flow_avg ], and wall shear stress) were analyzed based on 4D flow data. Cerebral infarction, defined as the occurrence of events, in 124 brain hemispheres was determined according to clinical symptoms and conventional brain MR imaging.

STATISTICAL TESTS: The independent-samples T test was used to evaluate differences in ICA hemodynamics between infarcted and non-infarcted hemispheres. Binary logistic regression was performed to investigate the relationship between ICA hemodynamics and events. A P value < 0.05 was considered statistically significant.

RESULTS: Sixty-one infarcted hemispheres (eight hemispheres with acute ischemic damage, 30 with chronic ischemic damage, and 23 with chronic hemorrhagic damage) had cerebrovascular events and 63 non-infarcted hemispheres did not. The hemodynamic parameters in the infarcted hemispheres (V_max : P < 0.001; V_avg : P = 0.003; and Flow_avg : P = 0.004) were significantly lower than those in the non-infarcted hemispheres. However, V_max (P = 0.052), V_avg (P = 0.107), and Flow_avg (P = 0.074) were not significantly different among hemispheres with acute ischemic lesions, chronic ischemic lesions and chronic hemorrhagic lesions. V_max (odds ratio 3.033, 95% CI: 1.075-8.562) was independently associated with cerebrovascular events.

DATA CONCLUSION: V_max maybe a higher risk factor of cerebrovascular events in MMA patients.

EVIDENCE LEVEL: 2 TECHNICAL EFFICACY STAGE: 3.

PMID:36349829 | DOI:10.1002/jmri.28522

Adv Mater. 2022 Nov 9:e2207741. doi: 10.1002/adma.202207741. Online ahead of print.

ABSTRACT

Switchable metal-organic frameworks change their structure in time and selectively open their pores adsorbing guest molecules, leading to highly selective separation, pressure amplification, sensing, and actuation applications. The three-dimensional engineering of metal-organic frameworks has reached a high level of maturity, but spatiotemporal evolution opens a new perspective towards engineering materials in the 4^th dimension (time) by t-axis design, in essence exploiting the deliberate tuning of activation barriers. This work demonstrates the first example in which an explicit temporal engineering of a switchable metal-organic framework (DUT-8, [M₁ M₂ (2,6-ndc)₂ dabco]_n , 2,6-ndc = 2,6,-naphthalene dicarboxylate, dabco = 1,4 diazabicyclo[2.2.2]octane, M₁ = Ni, M₂ = Co) is presented. The temporal response is deliberately tuned by variations in cobalt content. We present a spectrum of advanced analytical methods for analyzing the switching kinetics stimulated by vapor adsorption using in situ time-resolved techniques ranging from ensemble adsorption and advanced synchrotron X-ray diffraction experiments to individual crystal analysis. A novel analysis technique based on microscopic observation of individual crystals in a microfluidic channel reveals the lowest limit for adsorption switching reported so far. Differences in the spatiotemporal response of crystal ensembles originate from an induction time that varies statistically and widens characteristically with increasing cobalt content reflecting increasing activation barriers. This article is protected by copyright. All rights reserved.

PMID:36349824 | DOI:10.1002/adma.202207741

Proteomics. 2022 Nov 9:e2200092. doi: 10.1002/pmic.202200092. Online ahead of print.

ABSTRACT

Proteomics data are often plagued with missingness issues. These missing values (MVs) threaten the integrity of subsequent statistical analyses by reduction of statistical power, introduction of bias, and failure to represent the true sample. Over the years, several categories of missing value imputation (MVI) methods have been developed and adapted for proteomics data. These MVI methods perform their tasks based on different prior assumptions (e.g., data is normally or independently distributed) and operating principles (e.g., the algorithm is built to address random missingness only), resulting in varying levels of performance even when dealing with the same dataset. Thus, to achieve a satisfactory outcome, a suitable MVI method must be selected. To guide decision making on suitable MVI method, we provide a decision chart which facilitates strategic considerations on datasets presenting different characteristics. We also bring attention to other issues that can impact proper MVI such as the presence of confounders (e.g., batch effects) which can influence MVI performance. Thus, these too, should be considered during or before MVI. This article is protected by copyright. All rights reserved.

PMID:36349819 | DOI:10.1002/pmic.202200092

Proteomics. 2022 Nov 9:e2200013. doi: 10.1002/pmic.202200013. Online ahead of print.

ABSTRACT

There are multiple reasons why the next generation of biological and medical studies require increasing numbers of samples. First, many conditions need to be considered to produce generalisable results. For example, biological systems are dynamic, and the effect of a perturbation depends on the genetic background and environment. Moreover, human population and clinical studies only reach sufficient statistical power if conducted at scale and with precise measurement methods. Finally, many proteins remain without sufficient functional annotations, because they have not been systematically studied under a broad range of conditions. In this review, we discuss the latest technical developments in mass spectrometry-based proteomics that facilitate large-scale studies by fast and efficient chromatography, fast scanning mass spectrometers, data-independent acquisition (DIA), and new software. We further highlight recent studies which demonstrate how high-throughput proteomics can be applied to capture biological diversity, annotate gene functions or to generate predictive and prognostic models for human disease. This article is protected by copyright. All rights reserved.

PMID:36349817 | DOI:10.1002/pmic.202200013