Predictive factors for the surgical treatment of necrotizing enterocolitis in preterm infants: a single-center retrospective study

Background Necrotizing enterocolitis (NEC) is a gastrointestinal disease that tends to occur in premature infants. Some features may be associated with an increased probability that preterm infants with NEC will require surgical treatment. This study aimed to identify the factors that increased the probability of surgical treatment in infants with NEC. Methods We retrospectively analyzed the data of premature infants with NEC who were hospitalized at The Affiliated Hospital of Qingdao University from April 2011 to April 2021. According to the treatments received, these patients were divided into medical NEC group and surgical NEC group. The perinatal characteristics, clinical manifestations, and laboratory values before the onset of NEC were subjected to univariate and multivariate analyses. Results A total of 623 preterm infants with NEC (> Bell’s stage I) were included in this study, including 350 (56%) who received surgical treatment and 273 (44%) who received conservative medical treatment. Multivariate analysis showed that lower gestational age (P = 0.001, odds ratio (OR) (95% CI) = 0.91[0.86–0.96]), early occurrence of NEC (P = 0.003, OR (95% CI) = 0.86 [0.77–0.95]), hemodynamically significant patent ductus arteriosus (P = 0.003, OR (95% CI) = 7.50 [2.03–28.47]), and low serum bicarbonate (P = 0.043, OR (95% CI) = 0.863 [0.749–0.995]) were associated with an increased probability of surgical treatment in preterm infants with NEC. Conclusions Our findings were applied to identify potential predictors for surgical treatment in preterm infants with NEC, which may facilitate early decisive management.

Pre-Birth and Early-Life Factors Associated With the Timing of Adiposity Peak and Rebound: A Large Population-Based Longitudinal Study

Background: The late occurrence of adiposity peak (AP) and the early occurrence of adiposity rebound (AR) are considered the earliest indicators for obesity and its related health conditions later in life. However, there is still limited information for their upstream factors. Therefore, in this study, we aimed to identify the parental and child factors associated with the timing of AP and AR in the early stage of life.Methods: This is a population-based longitudinal study conducted in Shanghai, China. The BMI data of children born between September 2010 and October 2013 were followed from birth to 80 months. Subject-specific body mass index trajectories were fitted by non-linear mixed-effect models with natural cubic spline functions, and the individual's age at AP and AR was estimated. The generalized linear regression models were applied to identify the upstream factors of late occurrence of AP and early occurrence AR.Results: For 7,292 children with estimated AP, boys were less likely to have a late AP [adjusted risk ratio (RR) = 0.83, 95% confidence interval (CI): 0.77–0.90, p < 0.001], but preterm born children had a higher risk of a late AP (adjusted RR = 1.25, 95% CI: 1.07–1.47, p < 0.01). For 10,985 children with estimated AR, children with breastfeeding longer than 4 months were less likely to have an early AR (adjusted RR = 0.80, 95% CI: 0.73–0.87, p < 0.001), but children who were born to advanced-age mothers and who were born small for gestational age had a higher risk of having an early AR (adjusted RR = 1.21, 95% CI: 1.07–1.36, p < 0.01; adjusted RR = 1.20, 95% CI: 1.04–1.39, p = 0.01).Conclusions: Modifiable pre-birth or early-life factors associated with the timing of AP or AR were found. Our findings may help develop prevention and intervention strategies at the earliest stage of life to control later obesity and the health conditions and diseases linked to it.

The Cold Hand Sign in Multiple System Atrophy: Frequency-Associated Factors and Its Impact on Survival

Background: Few studies have focused on the cold hand sign (CHS), a red flag symptom, in multiple system atrophy (MSA).Objective: This study aimed to investigate the frequency and correlative factors of CHS in patients with MSA and the impact of its early occurrence on the survival of these patients.Methods: A total of 483 patients with MSA were enrolled in this study, and the motor and non-motor symptoms between patients with MSA with and without CHS were compared. Moreover, patients with disease duration ≤ 3 years at baseline were followed, and the association between CHS and survival of patients with MSA was examined.Results: The frequencies of CHS in patients with MSA were 20, 15.4, and 25.3% in MSA, MSA-parkinsonian subtype (MSA-P), and MSA-cerebellar subtype (MSA-C), respectively. Higher Unified Multiple System Atrophy Rating Scale (UMSARS) scores and higher Non-Motor Symptom Scale (NMSS) scores at baseline were associated with CHS in MSA. CHS was associated with shorter survival after adjusting for baseline diagnosis subtype, age at onset, sex, orthostatic hypotension, disease duration, autonomic onset, UMSARS total score, and NMSS score (p = 0.001; HR = 3.701; 95% CI = 1.765–7.760).Conclusion: CHS is not rare in patients with MSA. Greater disease severity and more severe non-motor symptoms were associated with CHS in patients with MSA. Patients with early occurrence of CHS had a poor prognosis.

Molecular Dynamics Research on the Impact of Vacancies on Cu Precipitation in BCC-Fe

The molecular dynamics (MD) simulation method was used to explore the impact of vacancy concentration (0 at%, 0.1 at% and 0.2 at%) on the diffusion and precipitation rate of Cu atoms in the Fe-3.5Cu alloy and the growth of Cu precipitation during the aging process of the alloy. The mechanism of the influence of Cu precipitation relative to the tensile properties of Fe-3.5Cu alloy was investigated. The results showed that the presence of vacancies will promote the diffusion and precipitation of Cu atoms in the Fe-3.5Cu alloy, but the diffusion and precipitation rate of Cu atoms does not always increase with the increase in vacancies. In the alloy containing 0.2 at% vacancies, the diffusion and precipitation rate of Cu atoms is lower than that in the alloy containing 0.1 at% vacancies. During the aging process, when the alloy contains no vacancies, no Cu precipitates will be produced. In the alloy containing 0.1 at% vacancies, the size of the Cu precipitates produced is larger than the size of the Cu precipitates produced in the alloy containing 0.2 at% vacancies, but the number of precipitates is less than that in the alloy with 0.2 at% vacancies. During the tensile process, the Cu precipitates will promote early occurrence of phase transition of the internal crystal structure in the Fe-3.5Cu alloy system, and lead to the generation of vacancy defects in the system, thus weakening the yield strength and strain hardening strength of the alloy.

Is Oxidative Stress the Link Between Cerebral Small Vessel Disease, Sleep Disruption, and Oligodendrocyte Dysfunction in the Onset of Alzheimer’s Disease?

Oxidative stress is an early occurrence in the development of Alzheimer’s disease (AD) and one of its proposed etiologic hypotheses. There is sufficient experimental evidence supporting the theory that impaired antioxidant enzymatic activity and increased formation of reactive oxygen species (ROS) take place in this disease. However, the antioxidant treatments fail to stop its advancement. Its multifactorial condition and the diverse toxicological cascades that can be initiated by ROS could possibly explain this failure. Recently, it has been suggested that cerebral small vessel disease (CSVD) contributes to the onset of AD. Oxidative stress is a central hallmark of CSVD and is depicted as an early causative factor. Moreover, data from various epidemiological and clinicopathological studies have indicated a relationship between CSVD and AD where endothelial cells are a source of oxidative stress. These cells are also closely related to oligodendrocytes, which are, in particular, sensitive to oxidation and lead to myelination being compromised. The sleep/wake cycle is another important control in the proliferation, migration, and differentiation of oligodendrocytes, and sleep loss reduces myelin thickness. Moreover, sleep plays a crucial role in resistance against CSVD, and poor sleep quality increases the silent markers of this vascular disease. Sleep disruption is another early occurrence in AD and is related to an increase in oxidative stress. In this study, the relationship between CSVD, oligodendrocyte dysfunction, and sleep disorders is discussed while focusing on oxidative stress as a common occurrence and its possible role in the onset of AD.

Topology identifies emerging adaptive mutations in SARS-CoV-2

The COVID-19 pandemic has lead to a worldwide effort to characterize its evolution through the mapping of mutations in the genome of the coronavirus SARS-CoV-2. As the virus spreads and evolves it acquires new mutations that could have important public health consequences, including higher transmissibility, morbidity, mortality, and immune evasion, among others. Ideally, we would like to quickly identify new mutations that could confer adaptive advantages to the evolving virus by leveraging the large number of SARS-CoV-2 genomes. One way of identifying adaptive mutations is by looking at convergent mutations, mutations in the same genomic position that occur independently. The large number of currently available genomes, more than a million at this moment, however precludes the efficient use of phylogeny-based techniques. Here, we establish a fast and scalable Topological Data Analysis approach for the early warning and surveillance of emerging adaptive mutations of the coronavirus SARS-CoV-2 in the ongoing COVID-19 pandemic. Our method relies on a novel topological tool for the analysis of viral genome datasets based on persistent homology. It systematically identifies convergent events in viral evolution merely by their topological footprint and thus overcomes limitations of current phylogenetic inference techniques. This allows for an unbiased and rapid analysis of large viral datasets. We introduce a new topological measure for convergent evolution and apply it to the complete GISAID dataset as of February 2021, comprising 303,651 high-quality SARS-CoV-2 isolates taken from patients all over the world since the beginning of the pandemic. A complete list of mutations showing topological signals of convergence is compiled. We find that topologically salient mutations on the receptor-binding domain appear in several variants of concern and are linked with an increase in infectivity and immune escape. Moreover, for many adaptive mutations the topological signal precedes an increase in prevalence. We demonstrate the capability of our method to effectively identify emerging adaptive mutations at an early stage. By localizing topological signals in the dataset, we are able to extract geo-temporal information about the early occurrence of emerging adaptive mutations. The identification of these mutations can help to develop an alert system to monitor mutations of concern and guide experimentalists to focus the study of specific circulating variants.