Tag: pubmed

Bull Math Biol. 2023 Jul 4;85(8):76. doi: 10.1007/s11538-023-01170-3.

ABSTRACT

The dynamics of a chemical reaction network (CRN) is often modeled under the assumption of mass action kinetics by a system of ordinary differential equations (ODEs) with polynomial right-hand sides that describe the time evolution of concentrations of chemical species involved. Given an arbitrarily large integer [Formula: see text], we show that there exists a CRN such that its ODE model has at least K stable limit cycles. Such a CRN can be constructed with reactions of at most second-order provided that the number of chemical species grows linearly with K. Bounds on the minimal number of chemical species and the minimal number of chemical reactions are presented for CRNs with K stable limit cycles and at most second order or seventh-order kinetics. We also show that CRNs with only two chemical species can have K stable limit cycles, when the order of chemical reactions grows linearly with K.

PMID:37402077 | DOI:10.1007/s11538-023-01170-3

J Immigr Minor Health. 2023 Jul 4. doi: 10.1007/s10903-023-01513-1. Online ahead of print.

ABSTRACT

Research on COVID-19 vaccine hesitancy has been sparse among Latino/a immigrants, a population at high risk for infection. This exploratory study examines rates of vaccine acceptance and its association with psychological antecedents of vaccination among Latino/a immigrants. A cross-sectional telephone survey on perceptions of COVID-19 was administered between October 2020 to February 2021 in South Florida to 200 adult Latino/a immigrants. Descriptive statistics, bivariate analysis, and logistic regression were employed to determine the influence of independent variables on vaccine acceptance. Most participants indicated a willingness to get vaccinated. Participants with higher confidence (aOR = 10.2, 95% CI: 4.8-21.8) and collective responsibility scores were (aOR = 3.1, 95%CI:1.3-6.9) more likely to report vaccine acceptance than those with lower scores. No other psychological antecedents or demographic variables were significantly associated with vaccine acceptance. Study results provide insights into motivating factors for vaccination that can inform culturally tailored education campaigns to increase vaccine acceptability in this population.

PMID:37402075 | DOI:10.1007/s10903-023-01513-1

Arch Virol. 2023 Jul 4;168(8):201. doi: 10.1007/s00705-023-05830-6.

ABSTRACT

Since 1987, infectious bursal disease virus (IBDV) has circulated and evolved in Vietnam, but little is known about the genotypes present. IBDV samples were collected in 1987, 2001-2006, 2008, 2011, 2015-2019, and 2021 in 18 provinces. We conducted phylogenotyping analysis based on an alignment of 143 VP2-HVR (hypervariable region) sequences from 64 Vietnamese isolates (26 previous and 38 additional sequences and two vaccines, and alignment of 82 VP1 B-marker sequences, including one vaccine and four Vietnamese field strains. The analysis identified three A-genotypes, A1, A3, and A7, and two B-genotypes, B1 and B3, among the Vietnamese IBDV isolates. The lowest average evolutionary distance (8.6%) was seen between the A1 and A3 genotypes, and the highest (21.7%) was between A5 and A7, while there was a distance of 14% between B1 and B3 and 17% between B3 and B2. Unique signature residues were observed for genotypes A2, A3, A5, A6, and A8, which could be used for genotypic discrimination. A timeline statistical summary revealed that the A3-genotype predominated (79.8% presence) in Vietnam from 1987 to 2021 and that it remained the dominant IBDV genotype over the last five years (2016-2021). The current study contributes to a better understanding of the circulating genotypes and evolution of IBDV in Vietnam and worldwide.

PMID:37402052 | DOI:10.1007/s00705-023-05830-6

Radiol Med. 2023 Jul 4. doi: 10.1007/s11547-023-01669-8. Online ahead of print.

ABSTRACT

PURPOSE: To assess the diagnostic accuracy of double inversion recovery (DIR) magnetic resonance imaging (MRI) sequences for synovitis of the wrist joints in patients with rheumatoid arthritis (RA).

MATERIAL AND METHODS: Participants with newly diagnosed RA were enrolled between November 2019 and November 2020. MRI examinations of the wrist joints were performed using a contrast-enhanced T1-weighted imaging sequence (CE-T1WI) and DIR sequence. We measured synovitis score, number of synovial areas, synovial volume, mean synovium-to-bone signal ratio (SBR), and synovial contrast-to-noise ratio (SNR). The inter-reviewer agreement rated on a four-point scale was evaluated by calculating the weighted k statistics. Two MRI sequences were assessed using Bland-Altman analyses, and the diagnostic performance of DIR images was calculated using the chi-square test.

RESULTS: A total of 47 participants were evaluated, and 282 joint regions in 5076 images were reviewed by two readers. There was no significant difference in synovitis scores (P = 0.67), number of synovial areas (P = 0.89), and synovial volume (P = 0.086) between the two MRI sequences. DIR images showed better SBR and SNR (all P < 0.01). There was good agreement between the two reviewers in terms of synovitis distribution (κ = 0.79). The synovitis was well agreed upon by the two readers according to Bland-Altman analyses. Using CE-T1WI as the reference standard, DIR imaging demonstrated a sensitivity of 94.1% and a specificity of 84.6% at the patient level.

CONCLUSION: The non-contrast DIR sequence showed good consistency with CE-T1WI and potential for evaluating synovitis in patients with RA.

PMID:37402026 | DOI:10.1007/s11547-023-01669-8

J Med Ultrason (2001). 2023 Jul 4. doi: 10.1007/s10396-023-01333-8. Online ahead of print.

ABSTRACT

PURPOSE: We aimed to compare vibration-controlled transient elastography (VCTE) with shear wave elastography (SWE) without previous analysis and generate regression equations between VCTE and new point SWE using combination-elastography.

METHODS: Overall, 829 patients with chronic liver disease were enrolled in this study. Patients with a skin-liver capsule distance > 25 mm were excluded. The reproducibility of VCTE and SWE was confirmed in a phantom study and a clinical study. Considering that combination-elastography allows measurement based on strain elastography, a similar analysis was performed for the liver fibrosis index (LFI), which is a quantitative value for evaluation of liver fibrosis calculated using strain elastography image features. Regression equations between the VCTE and SWE values were obtained based on linear regression analysis.

RESULTS: In the phantom study and clinical study, there was a strong correlation between VCTE and SWE [r = 0.995 (p < 0.001) and r = 0.747 (p < 0.001), respectively). The regression equation between VCTE and SWE was VCTE (kPa) = 1.09 × point SWE (kPa) – 0.17. The Bland-Altman plots revealed no statistically significant bias. Meanwhile, there was no correlation between VCTE and LFI (r = 0.279). There was a statistically significant bias between VCTE and LFI in the Bland-Altman plots. The inter-operator reliability showed a good intraclass correlation coefficient of 0.760 (95% confidence interval: 0.720-0.779).

CONCLUSION: Liver stiffness measured using point SWE was comparable to that measured using VCTE.

PMID:37402022 | DOI:10.1007/s10396-023-01333-8

Int J Legal Med. 2023 Jul 4. doi: 10.1007/s00414-023-03055-5. Online ahead of print.

ABSTRACT

PURPOSE: To investigate prediction of age older than 18 years in sub-adults using tooth tissue volumes from MRI segmentation of the entire 1st and 2nd molars, and to establish a model for combining information from two different molars.

MATERIALS AND METHODS: We acquired T2 weighted MRIs of 99 volunteers with a 1.5-T scanner. Segmentation was performed using SliceOmatic (Tomovision©). Linear regression was used to analyse the association between mathematical transformation outcomes of tissue volumes, age, and sex. Performance of different outcomes and tooth combinations were assessed based on the p-value of the age variable, common, or separate for each sex, depending on the selected model. The predictive probability of being older than 18 years was obtained by a Bayesian approach using information from the 1st and 2nd molars both separately and combined.

RESULTS: 1st molars from 87 participants, and 2nd molars from 93 participants were included. The age range was 14-24 years with a median age of 18 years. The transformation outcome (high signal soft tissue + low signal soft tissue)/total had the strongest statistical association with age for the lower right 1st (p= 7.1*10^-4 for males) and 2nd molar (p=9.44×10^-7 for males and p=7.4×10^-10 for females). Combining the lower right 1st and 2nd molar in males did not increase the prediction performance compared to using the best tooth alone.

CONCLUSION: MRI segmentation of the lower right 1st and 2nd molar might prove useful in the prediction of age older than 18 years in sub-adults. We provided a statistical framework to combine the information from two molars.

PMID:37402013 | DOI:10.1007/s00414-023-03055-5

Int J Legal Med. 2023 Jul 4. doi: 10.1007/s00414-023-03050-w. Online ahead of print.

ABSTRACT

INTRODUCTION: Due to its peculiar anatomy and physiology, the pericardial fluid is a biological matrix of particular interest in the forensic field. Despite this, the available literature has mainly focused on post-mortem biochemistry and forensic toxicology, while to the best of authors’ knowledge post-mortem metabolomics has never been applied. Similarly, estimation of the time since death or post-mortem interval based on pericardial fluids has still rarely been attempted.

OBJECTIVES: We applied a metabolomic approach based on ¹H nuclear magnetic resonance spectroscopy to ascertain the feasibility of monitoring post-mortem metabolite changes on human pericardial fluids with the aim of building a multivariate regression model for post-mortem interval estimation.

METHODS: Pericardial fluid samples were collected in 24 consecutive judicial autopsies, in a time frame ranging from 16 to 170 h after death. The only exclusion criterion was the quantitative and/or qualitative alteration of the sample. Two different extraction protocols were applied for low molecular weight metabolites selection, namely ultrafiltration and liquid-liquid extraction. Our metabolomic approach was based on the use of ¹H nuclear magnetic resonance and multivariate statistical data analysis.

RESULTS: The pericardial fluid samples treated with the two experimental protocols did not show significant differences in the distribution of the metabolites detected. A post-mortem interval estimation model based on 18 pericardial fluid samples was validated with an independent set of 6 samples, giving a prediction error of 33-34 h depending on the experimental protocol used. By narrowing the window to post-mortem intervals below 100 h, the prediction power of the model was significantly improved with an error of 13-15 h depending on the extraction protocol. Choline, glycine, ethanolamine, and hypoxanthine were the most relevant metabolites in the prediction model.

CONCLUSION: The present study, although preliminary, shows that PF samples collected from a real forensic scenario represent a biofluid of interest for post-mortem metabolomics, with particular regard to the estimation of the time since death.

PMID:37402012 | DOI:10.1007/s00414-023-03050-w

Childs Nerv Syst. 2023 Jul 4. doi: 10.1007/s00381-023-06061-5. Online ahead of print.

ABSTRACT

PURPOSE: Optic pathway gliomas (OPGs) occur in 15% of patients with neurofibromatosis type 1 (NF1). Their location renders biopsy or surgical resection difficult because of the risk of vision loss. Therefore, only a few NF1-OPGs have been used for tissue diagnosis, and only a few analyses have been published on the molecular changes that drive tumorigenesis.

METHODS: Due to this reason, we evaluated 305 NF1 patients, 34 with OPG and 271 without OPG for germ line mutations. All subjects underwent clinical examination and DNA analysis of NF1, confirming the diagnosis of NF1.

RESULTS: Clinically, the group with OPG had a significantly higher incidence of bone dysplasia (P < 0.001) and more café-au-lait spots (P = 0.001) compared to those in the group without OPG. The frequency of Lisch nodules was on the borderline of statistical significance (P = 0.058), whereas the frequency of neurofibromas did not differ significantly (cutaneous, P = 0.64; plexiform, P = 0.44). Individuals with OPG mostly had mutations in the first one-third of the NF1 gene compared with that in patients who did not have OPG. Some identical mutations were detected in unrelated families with NF1-OPG.

CONCLUSION: The observation of certain phenotypic features and the correlation between genotype and phenotype might help to determine the risk of developing OPG with NF1.

PMID:37401974 | DOI:10.1007/s00381-023-06061-5

Arch Orthop Trauma Surg. 2023 Jul 4. doi: 10.1007/s00402-023-04952-5. Online ahead of print.

ABSTRACT

INTRODUCTION: The objective of this study was to determine if operative fixation of clavicle fractures in patients with non-operatively treated ipsilateral rib fractures is associated with a lower overall analgesic requirement and improved respiratory function.

MATERIALS AND METHODS: A retrospective matched cohort study was conducted involving patients admitted to a single tertiary trauma centre having sustained a clavicle fracture with ipsilateral rib fracture/s between January 2014 and June 2020. Patients were excluded if brain, abdominal, pelvic, or lower limb trauma was identified. 31 patients with operative clavicle fixation (study group) were matched 1:1 to 31 patients with non-operative management of the clavicle fracture (control group) based on age, sex, number of rib fractures and injury severity score. The primary outcome was the number of analgesic types used, and the secondary outcome was respiratory function.

RESULTS: The study group required a mean of 3.50 types of analgesia prior to surgery which decreased to 1.57 post-surgery. The control group required 2.92 types of analgesia, reducing to 1.65 after the date of surgery in the study group. A General Linear Mixed Model indicated that the intervention (operative vs. non-operative management) had statistically significant effects on the number of required analgesic types (p < 0.001, [Formula: see text] = 0.365), oxygen saturation (p = 0.001, [Formula: see text] = 0.341, 95% CI 0.153-0.529) and temporal decline in daily supplemental oxygen requirement (p < 0.001, [Formula: see text] = 0.626, 95% CI 0.455-0.756).

CONCLUSION: This study supported the hypothesis that operative clavicle fixation reduces short-term in-patient analgesia use and improves respiratory parameters in patients with ipsilateral rib fractures.

LEVEL OF EVIDENCE: Level III therapeutic study.

PMID:37401951 | DOI:10.1007/s00402-023-04952-5

Clin Neuroradiol. 2023 Jul 4. doi: 10.1007/s00062-023-01320-z. Online ahead of print.

ABSTRACT

PURPOSE: The 3D time-of-flight (TOF) magnetic resonance angiography (MRA) at 3T shows high sensitivity for intracranial aneurysms but is inferior to three-dimensional digital subtraction angiography (3D-DSA) regarding aneurysm characteristics. We applied an ultra-high-resolution (UHR) TOF-MRA using compressed sensing reconstruction to investigate the diagnostic performance in preinterventional evaluation of intracranial aneurysms compared to conventional TOF-MRA and 3D-DSA.

METHODS: In this study 17 patients with unruptured intracranial aneurysms were included. Aneurysm dimensions, configuration, image quality and sizing of endovascular devices were compared between conventional TOF-MRA at 3T and UHR-TOF with 3D-DSA as gold standard. Quantitatively, contrast-to-noise ratios (CNR) were compared between TOF-MRAs.

RESULTS: On 3D-DSA, 25 aneurysms in 17 patients were detected. On conventional TOF, 23 aneurysms were detected (sensitivity: 92.6%). On UHR-TOF, 25 aneurysms were detected (sensitivity: 100%). Image quality was not significantly different between TOF and UHR-TOF (p = 0.17). Aneurysm dimension measurements were significantly different between conventional TOF (3.89 mm) and 3D-DSA (4.2 mm, p = 0.08) but not between UHR-TOF (4.12 mm) and 3D-DSA (p = 0.19). Irregularities and small vessels at the aneurysm neck were more frequently correctly depicted on UHR-TOF compared to conventional TOF. Comparison of the planned framing coil diameter and flow-diverter (FD) diameter revealed neither a statistically significant difference between TOF and 3D-DSA (coil p = 0.19, FD p = 0.45) nor between UHR-TOF and 3D-DSA (coil: p = 0.53, FD 0.33). The CNR was significantly higher in conventional TOF (p = 0.009).

CONCLUSION: In this pilot study, ultra-high-resolution TOF-MRA visualized all aneurysms and accurately depicted aneurysm irregularities and vessels at the base of the aneurysm comparably to DSA, outperforming conventional TOF. UHR-TOF with compressed sensing reconstruction seems to represent a non-invasive alternative to pre-interventional DSA for intracranial aneurysms.

PMID:37401949 | DOI:10.1007/s00062-023-01320-z