A Novel Enhanced-Fluorescent Probe Based on DHLA-Stabilized Red-Emitting Copper Nanoclusters for Methimazole Detection Via Aggregation-Induced Emission Effect.

Herein, an aqueous phase synthesis approach was presented for the fabrication of copper nanoclusters (Cu NCs) with aggregation-induced emission (AIE) property, utilizing lipoic acid and NaBH4 as ligands and reducing agent, respectively. The as-synthesized Cu NCs exhibit an average size of 3.0 ± 0.2 nm and demonstrate strong solid-state fluorescence upon excitation with UV light. However, when dissolved in water, no observable fluorescent emission is detected in the aqueous solution of Cu NCs. Remarkably, the addition of Methimazole induced a significant red fluorescence from the aqueous solution of Cu NCs. This unexpected phenomenon can be ascribed to the aggregation of negatively charged Cu NCs caused by electrostatic interaction with positively charged imidazole groups in Methimazole, resulting in enhanced fluorescence through AIE mechanism. Therefore, there exists an excellent linear correlation between the fluorescent intensities of Cu NCs aqueous solution and the concentration of Methimazole within a range of 0.1-1.5 mM with a low limit of detection of 82.2 µM. Importantly, the designed enhanced-fluorescent nanoprobe based on Cu NCs exhibits satisfactory performance in assaying commercially available Methimazole tablets, demonstrating its exceptional sensitivity, reliability, and accuracy.

Identification of a shared gene signature and biological mechanism between diabetic foot ulcers and cutaneous lupus erythemnatosus by transcriptomic analysis.

Diabetic foot ulcers (DFU) and cutaneous lupus erythematosus (CLE) are both diseases that can seriously affect a patient's quality of life and generate economic pressure in society. Symptomatically, both DLU and CLE exhibit delayed healing and excessive inflammation; however, there is little evidence to support a molecular and cellular connection between these two diseases. In this study, we investigated potential common characteristics between DFU and CLE at the molecular level to provide new insights into skin diseases and regeneration, and identify potential targets for the development of new therapies. The gene expression profiles of DFU and CLE were obtained from the Gene Expression Omnibus (GEO) database and used for analysis. A total of 41 common differentially expressed genes (DEGs), 16 upregulated genes and 25 downregulated genes, were identified between DFU and CLE. GO and KEGG analysis showed that abnormalities in epidermal cells and the activation of inflammatory factors were both involved in the occurrence and development of DFU and CLE. Protein-protein interaction network (PPI) and sub-module analysis identified enrichment in seven common key genes which is KRT16, S100A7, KRT77, OASL, S100A9, EPGN and SAMD9. Based on these seven key genes, we further identified five miRNAs(has-mir-532-5p, has-mir-324-3p,has-mir-106a-5p,has-mir-20a-5p,has-mir-93-5p) and7 transcription factors including CEBPA, CEBPB, GLI1, EP30D, JUN,SP1, NFE2L2 as potential upstream molecules. Functional immune infiltration assays showed that these genes were related to immune cells. The CIBERSORT algorithm and Pearson method were used to determine the correlations between key genes and immune cells, and reverse key gene-immune cell correlations were found between DFU and CLE. Finally, the DGIbd database demonstrated that Paquinimod and Tasquinimod could be used to target S100A9 and Ribavirin could be used to target OASL. Our findings highlight common gene expression characteristics and signaling pathways between DFU and CLE, indicating a close association between these two diseases. This provides guidance for the development of targeted therapies and mutual interactions.

Chemical Vapor Deposition Synthesis of Intrinsic High-Temperature Ferroelectric 2D CuCrSe2.

Ultrathin 2D ferroelectrics with high Curie temperature are critical for multifunctional ferroelectric devices. However, the ferroelectric spontaneous polarization is consistently broken by the strong thermal fluctuations at high temperature, resulting in the rare discovery of high-temperature ferroelectricity in 2D materials. Here, a chemical vapor deposition method is reported to synthesize 2D CuCrSe2 nanosheets. The crystal structure is confirmed by scanning transmission electron microscopy characterization. The measured ferroelectric phase transition temperature of ultrathin CuCrSe2 is about ≈800 K. Significantly, the switchable ferroelectric polarization is observed in ≈5.2 nm nanosheet. Moreover, the in-plane and out-of-plane ferroelectric response are modulated by different maximum bias voltage. This work provides a new insight into the construction of 2D ferroelectrics with high Curie temperature.

Inhibition of CYP1A1 Alleviates Colchicine-Induced Hepatotoxicity.

Colchicine, a natural compound extracted from Colchicum autumnale, is a phytotoxin, but interestingly, it also has multiple pharmacological activities. Clinically, colchicine is widely used for the treatment of gouty arthritis, familial Mediterranean fever, cardiovascular dysfunction and new coronary pneumonia. However, overdose intake of colchicine could cause lethal liver damage, which is a limitation of its application. Therefore, exploring the potential mechanism of colchicine-induced hepatotoxicity is meaningful. Interestingly, it was found that CYP1A1 played an important role in the hepatotoxicity of colchicine, while it might also participate in its metabolism. Inhibition of CYP1A1 could alleviate oxidative stress and pyroptosis in the liver upon colchicine treatment. By regulating CYP1A1 through the CASPASE-1-GSDMD pathway, colchicine-induced liver injury was effectively relieved in a mouse model. In summary, we concluded that CYP1A1 may be a potential target, and the inhibition of CYP1A1 alleviates colchicine-induced liver injury through pyroptosis regulated by the CASPASE-1-GSDMD pathway.

Peer relationships mediate the pathways from behavioral qualities to United States and Chinese children's loneliness.

Loneliness is a perceived deficit in social relationships that is nested within broader cultural meaning systems. This longitudinal study examined predictors of loneliness in Chinese and U.S. children with the hypothesis that peer relationship parameters (number of friends, social preference, and popularity) mediate the associations between behavior qualities and loneliness differently across countries. Fifth-grade Chinese (n = 576, Mage = 10.58 years) and U.S. (White, Black, Asian, n = 540; Mage = 10.23 years) children completed two waves of assessment within an academic year. Shyness and athletic competence more strongly predicted loneliness for U.S. children, and academic ability, and aggression more strongly predicted loneliness for Chinese children. Popularity was a mediator for U.S. children but not Chinese children.

The relationship between social responsibility fulfilment and industry competitiveness: Empirical evidence from construction industry in China.

Social responsibility fulfilment is an important part of the operation management (OM) and competitiveness of the construction industry (CIC). This study investigates the mechanisms through which social responsibility fulfilment in the construction industry affects industry competitiveness and the mediating role of industry operations management. From the intra-organizational stakeholder perspective, social responsibility fulfilment (SR) is divided into two dimensions: shareholder-dimensional (SH) and employee-dimensional social responsibility fulfilment (EM). By analysing a panel of the construction industry in 12 provinces of China from 2015 to 2020, an inverted U-shaped relationship between social responsibility fulfilment and construction industry competitiveness and between shareholder-dimensional social responsibility fulfilment and construction industry competitiveness was found, while a U-shaped relationship between employee-dimensional social responsibility fulfilment and construction industry competitiveness was found. Furthermore, social responsibility fulfilment and shareholder-dimensional social responsibility fulfilment had significant effects on operation management. Additionally, the study concludes that operation management is positively related to construction industry competitiveness and plays a partially mediating role between social responsibility fulfilment and construction industry competitiveness. The findings enrich the theoretical basis of the relationship between social responsibility fulfilment and competitiveness and demonstrates important management significance for the construction industry in managing its social responsibility behaviour and improving industry competitiveness, thus promoting high-quality development of the construction industry.

ZnS QDs Stabilized Concurrently with Glutathione and L-cysteine for Highly Sensitive Determining Adriamycin Based on the Fluorescence Enhancement Mechanism.

In this work, a facile and fast aqueous-phase synthetic method is proposed to prepare water-soluble ZnS quantum dots stabilized simultaneously with glutathione and L-cysteine (ZnS QDs-GSH/L-Cys). As-synthesized ZnS QDs-GSH/L-Cys were monodispersed spherical nanocrystals with a mean diameter of 5.0 ± 0.7 nm. Besides, the obtained ZnS QDs-GSH/L-Cys emitted more intensive blue fluorescence and exhibited an improved stability in aqueous solution compared with ZnS quantum dots merely stabilized with GSH (ZnS QDs-GSH). Interestingly, Adriamycin, a representative anticancer drug, was added into the solution of ZnS QDs-GSH/L-Cys, the blue fluorescence of ZnS QDs-GSH/L-Cys was greatly enhanced instead of being quenched, which indicated that ZnS QDs-GSH/L-Cys can be used as an enhanced-fluorescence nanoprobe for determining Adriamycin. The observed fluorescent enhancement could be attributed to the blocking of photoinduced electron transfer (PET) in ZnS QDs-GSH/L-Cys due to the electrostatic interaction between the -COO- groups on the surface of quantum dots and the -NH3+ groups in Adriamycin, followed by the coordination interaction among ZnS QDs-GSH/L-Cys and Adriamycin. The fluorescence intensity of ZnS QDs-GSH/L-Cys presented a good linear response with the concentration of Adriamycin ranging from 2.0 to 20 µg•mL-1. The proposed fluorescent nanoprobe exhibited an excellent sensitivity with the LOD of 0.1 µg•mL-1 and a good accuracy for detecting Adriamycin.

Parabacteroides distasonis ameliorates hepatic fibrosis potentially via modulating intestinal bile acid metabolism and hepatocyte pyroptosis in male mice.

Parabacteroides distasonis (P. distasonis) plays an important role in human health, including diabetes, colorectal cancer and inflammatory bowel disease. Here, we show that P. distasonis is decreased in patients with hepatic fibrosis, and that administration of P. distasonis to male mice improves thioacetamide (TAA)- and methionine and choline-deficient (MCD) diet-induced hepatic fibrosis. Administration of P. distasonis also leads to increased bile salt hydrolase (BSH) activity, inhibition of intestinal farnesoid X receptor (FXR) signaling and decreased taurochenodeoxycholic acid (TCDCA) levels in liver. TCDCA produces toxicity in mouse primary hepatic cells (HSCs) and induces mitochondrial permeability transition (MPT) and Caspase-11 pyroptosis in mice. The decrease of TCDCA by P. distasonis improves activation of HSCs through decreasing MPT-Caspase-11 pyroptosis in hepatocytes. Celastrol, a compound reported to increase P. distasonis abundance in mice, promotes the growth of P. distasonis with concomitant enhancement of bile acid excretion and improvement of hepatic fibrosis in male mice. These data suggest that supplementation of P. distasonis may be a promising means to ameliorate hepatic fibrosis.

Energy delivery guided by indirect calorimetry in critically ill patients: a systematic review and meta-analysis.

BACKGROUND: The use of indirect calorimetry (IC) is increasing due to its precision in resting energy expenditure (REE) measurement in critically ill patients. Thus, we aimed to evaluate the clinical outcomes of an IC-guided nutrition therapy compared to predictive equations strategy in such a patient population. METHODS: We searched PubMed, EMBASE, and Cochrane library databases up to October 25, 2020. Randomized controlled trials (RCTs) were included if they focused on energy delivery guided by either IC or predictive equations in critically ill adults. We used the Cochrane risk-of-bias tool to assess the quality of the included studies. Short-term mortality was the primary outcome. The meta-analysis was performed with the fixed-effect model or random-effect model according to the heterogeneity. RESULTS: Eight RCTs with 991 adults met the inclusion criteria. The overall quality of the included studies was moderate. Significantly higher mean energy delivered per day was observed in the IC group, as well as percent delivered energy over REE targets, than the control group. IC-guided energy delivery significantly reduced short-term mortality compared with the control group (risk ratio = 0.77; 95% CI 0.60 to 0.98; I2 = 3%, P = 0.03). IC-guided strategy did not significantly prolong the duration of mechanical ventilation (mean difference [MD] = 0.61 days; 95% CI - 1.08 to 2.29; P = 0.48), length of stay in ICU (MD = 0.32 days; 95% CI - 2.51 to 3.16; P = 0.82) and hospital (MD = 0.30 days; 95% CI - 3.23 to 3.83; P = 0.87). Additionally, adverse events were similar between the two groups. CONCLUSIONS: This meta-analysis indicates that IC-guided energy delivery significantly reduces short-term mortality in critically ill patients. This finding encourages the use of IC-guided energy delivery during critical nutrition support. But more high-quality studies are still needed to confirm these findings.

Rapid classification and identification of chemical constituents in Epimedium koreanum Nakai by UPLC-Q-TOF-MS combined with data post-processing techniques.

INTRODUCTION: Epimedium koreanum Nakai (EKN), is a well-known Chinese herbal medicine for the treatment of osteoporosis, immunosuppression, tumours and cardiovascular diseases. Comprehensive component identification is essential for elucidation of its pharmacological mechanism and quality control. However, its complex chemical composition has caused certain difficulties in the analysis of this traditional Chinese medicine (TCM). Therefore, there is an urgent need to establish a method for rapid classification and identification of EKN chemical components. OBJECTIVE: To establish a method for rapid classification and identification of the main components of flavonoids, organic acids and alkaloids in EKN. METHODS: The samples were analysed by ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and data post-processing techniques. The UPLC system used a BEH C18 column to separate the total extract of EKN. The mobile phase consisted of 0.1% formic acid in water and acetonitrile, and the EKN extract was analysed by gradient elution at a flow rate of 0.4 mL/min. In both the positive and negative ion modes, the fragment information was obtained and compared with those of the characteristic fragmentations and neutral losses described in the literature to quickly identify the target compounds. RESULTS: Finally, we successfully screened out 51 chemical components, including 40 flavonoids, nine organic acids, and two alkaloids. CONCLUSION: The established method not only comprehensively analysed the chemical compositions of EKN, solved the difficult problems of analysis and identification of the complex chemical compositions of the TCM, but also further promoted the development of the application of chemical compositions of TCM.

Techniques and Strategies for Potential Protein Target Discovery and Active Pharmaceutical Molecule Screening in a Pandemic.

Viruses remain a major challenge in the fierce fight against diseases. There have been many pandemics caused by various viruses throughout the world over the years. Recently, the global outbreak of COVID-19 has had a catastrophic impact on human health and the world economy. Antiviral drug treatment has become another essential means to overcome pandemics in addition to vaccine development. How to quickly find effective drugs that can control the development of a pandemic is a hot issue that still needs to be resolved in medical research today. To accelerate the development of drugs, it is necessary to target the key target proteins in the development of the pandemic, screen active molecules, and develop reliable methods for the identification and characterization of target proteins based on the active ingredients of drugs. This article discusses key target proteins and their biological mechanisms in the progression of COVID-19 and other major epidemics. We propose a model based on these foundations, which includes identifying potential core targets, screening potential active molecules of core targets, and verifying active molecules. This article summarizes the related innovative technologies and methods. We hope to provide a reference for the screening of drugs related to pandemics and the development of new drugs.

Hexagonal layered group IV-VI semiconductors and derivatives: fresh blood of the 2D family.

New phases of group IV-VI semiconductors in 2D hexagonal structures are predicted and their unusual physical properties are revealed. The structures of monolayer group IV-VI semiconductors are similar to those of blue phosphorene and each unit has the same ten valence electrons. The band gap of 2D hexagonal group IV-VI semiconductors depends on both the thickness and stacking order. Atomic functionalization can induce ferromagnetism, and the Curie temperature can be tuned. Gapped Dirac fermions with zero mass are developed and this makes it exceed that of graphene. The Fermi velocity can be compared to or even above that of graphene.

Integrated Proteomics and Metabolomics Reveal the Mechanism of Nephrotoxicity Induced by Triptolide.

Triptolide (TP), the main active ingredient of Tripterygium wilfordii Hook F., has great potential in the treatment of autoimmune diseases. However, it has been found that the side effects of TP involve multiple organs and systems, of which the most serious side effects relate to the kidney. The mechanism of nephrotoxicity caused by TP requires further investigation. In the present study, we integrated proteomic and metabolomic methods to identify proteins and small molecule metabolites associated with TP-induced nephrotoxicity. There was a significant difference (p value <0.05) in the expression changes of 357 proteins for quantitative proteomics. In addition, high resolution metabolomic data showed significant changes in the levels of 9 metabolites, including hypoxanthine, PC(22:0/18:4), sphingosine, phenylalanine, etc. Finally, based on the Kyoto Encyclopaedia of Genes and Genomes (KEGG) database for network analysis, it was determined that the 7 differentially expressed proteins were highly correlated with these 9 metabolites. Enrichment analysis revealed that the metabolic pathways involved purine and pyrimidine metabolism, glycerol and phospholipid metabolism, sphingolipid metabolism, and amino acid metabolism. The key target proteins were verified by Western blot technology, and the mechanism of TP-induced nephrotoxicity was further elucidated to provide a basis for safe and rational application.

Integrative proteomics-metabolomics strategy reveals the mechanism of hepatotoxicity induced by Fructus Psoraleae.

Fructus Psoraleae (FP), one of the significant traditional Chinese medicines, has been reported to cause hepatotoxicity. However, the mechanism remains undetermined and the reported research is limited. In this study, a tandem mass tag (TMT)-based quantitative proteomics and metabolomics were used to reveal a more comprehensive effect caused by FP. The results showed that aqueous extract of FP can induce liver injury in rats. In total, 575 significantly changed proteins were identified by quantitative proteomics analysis, among which 352 proteins were significantly up-regulated and 223 proteins were significantly down-regulated in liver tissues. And we detected 14 biomarkers such as succinic acid, hypoxanthine, l-carnitine, phenylalanine, glutathione, and glycoursodeoxycholic acid. Correlation analysis of altered metabolites and proteins exhibited the aberrant regulation of metabolic pathways including bile secretion, glutathione metabolism, purine metabolism, glycerophospholipid metabolism, TCA cycle and pyruvate metabolism, which indicated the disorder of bile acid metabolism, oxidative stress, energy metabolism and immune system. Notably, the changed proteins including Cyp7a1, FXR, SHP, BSEP, Sult2a1, Nceh1 in bile acid metabolism may play an essential role in the hepatotoxicity induced by aqueous extract of FP. In conclusion, integrative proteomics and metabolomics provide the potential mechanism of hepatotoxicity induced by FP. SIGNIFICANCE: Fructus Psoraleae, a traditional Chinese medicine, is widely used in Asia for the treatment of osteoporosis and vitiligo. Recently, clinical and experimental reports reveal that FP can induce liver injury. However the mechanism of injury induced by FP is still unclear. In this study, we detected 352 significantly up-regulated proteins and 223 significantly down-regulated proteins in liver tissues by TMT-based quantitative proteomics. And 14 important metabolites were identified by metabolomics analysis. Through integrative analysis of the key metabolites and proteins, several metabolism pathways were selected, which implicated in bile acid metabolism, oxidative stress, energy metabolism, immune system. This is the first integrative study of proteomics and metabolomics for FP exposure, the finding clarified the potential mechanism of hepatotoxicity caused by FP and will promote rational use of FP in clinical application.

The use of latent class analysis to estimate the sensitivities and specificities of diagnostic tests for Squash vein yellowing virus in cucurbit species when there is no gold standard.

Squash vein yellowing virus (SqVYV) is the causal agent of viral watermelon vine decline, one of the most serious diseases in watermelon (Citrullus lanatus L.) production in the southeastern United States. At present, there is not a gold standard diagnostic test for determining the true status of SqVYV infection in plants. Current diagnostic methods for identification of SqVYV-infected plants or tissues are based on the reverse-transcription polymerase chain reaction (RT-PCR), tissue blot nucleic acid hybridization assays (TB), and expression of visual symptoms. A quantitative assessment of the performance of these diagnostic tests is lacking, which may lead to an incorrect interpretation of results. In this study, latent class analysis (LCA) was used to estimate the sensitivities and specificities of RT-PCR, TB, and visual assessment of symptoms as diagnostic tests for SqVYV. The LCA model assumes that the observed diagnostic test responses are linked to an underlying latent (nonobserved) disease status of the population, and can be used to estimate sensitivity and specificity of the individual tests, as well as to derive an estimate of the incidence of disease when a gold standard test does not exist. LCA can also be expanded to evaluate the effect of factors and was done here to determine whether diagnostic test performances varied among the type of plant tissue being tested (crown versus vine tissue), where plant samples were taken relative to the position of the crown (i.e., distance from the crown), host (i.e., genus), and habitat (field-grown versus greenhouse-grown plants). Results showed that RT-PCR had the highest sensitivity (0.94) and specificity (0.98) of the three tests. TB had better sensitivity than symptoms for detection of SqVYV infection (0.70 versus 0.32), while the visual assessment of symptoms was more specific than TB and, thus, a better indicator of noninfection (0.98 versus 0.65). With respect to the grouping variables, RT-PCR and TB had better sensitivity but poorer specificity for diagnosing SqVYV infection in crown tissue than it did in vine tissue, whereas symptoms had very poor sensitivity but excellent specificity in both tissues for all cucurbits analyzed in this study. Test performance also varied with habitat and genus but not with distance from the crown. The results given here provide quantitative measurements of test performance for a range of conditions and provide the information needed to interpret test results when tests are used in parallel or serial combination for a diagnosis.

Interpregnancy body mass index changes and risk of stillbirth.

BACKGROUND/AIMS: To examine the association between interpregnancy body mass index (BMI) change and stillbirth. METHODS: Retrospective study using Missouri maternally linked cohort files (1978-2005). A total of 218,389 women were used in the analysis. BMI was classified as: underweight (<18.5), normal (18.5-24.9), overweight (25-29.9), or obese (≥30.0). Weight change was defined based on BMI category (i.e. normal-normal, normal-obese, etc.). Cox proportional hazard regression models were used to generate adjusted hazard ratios (HR) and 95% CI for the risk of stillbirth in the second pregnancy. RESULTS: Significant findings were associated with interpregnancy BMI changes involving overweight mothers becoming obese (HR = 1.4, 95% CI 1.1-1.7), normal-weight mothers becoming overweight (HR = 1.2, 95% CI 1.0-1.4) or obese (HR = 1.5, 95% CI 1.1-2.1), or obese mothers maintaining their obesity status across the two pregnancies (HR = 1.4, 95% CI 1.2-1.7). Other weight change categories did not show significant risk elevation for stillbirth. CONCLUSIONS: BMI change appears to play an important role in subsequent stillbirth risk.

Changes in prepregnancy body mass index between pregnancies and risk of gestational and type 2 diabetes.

INTRODUCTION: We investigated whether changes in interpregnancy body mass index (BMI) influence the risk of gestational and type 2 diabetes among a cohort of women with two consecutive live, singleton births of 20-44 weeks gestation (n = 232,272). METHODS: Logistic regression models were used to examine the risk for development of gestational or type 2 diabetes during the second pregnancy. Mothers with normal weight for both pregnancies (normal-normal) served as the referent group. RESULTS: Across all BMI categories, mothers with significant weight gain (i.e., moving from a lower BMI category into a higher category) had an increased risk for the development of diabetes. Mothers who moved from normal prepregnancy weight (BMI = 18.5-24.9 kg/m²) in the first pregnancy to obese prepregnancy weight (BMI ≥ 30.0 kg/m²) in the second pregnancy showed the greatest increment in risk. These mothers exhibited a threefold risk for developing diabetes (OR = 3.21, 95% CI 2.76-3.73). Mothers who maintained their interpregnancy BMI weight category or who moved to a lower BMI category had reduced risk for gestational and type 2 diabetes. The risk associated with mothers who moved to a lower BMI category was approximately half that of the normal-normal BMI category. CONCLUSION: Interpregnancy weight gain is associated with a dose-response increase in risk of diabetes. Establishing a normal interpregnancy BMI may reduce the risk of diabetes.

Changes in prepregnancy body mass index between pregnancies and risk of preterm phenotypes.

We examined whether the risk of preterm birth and its subtypes (medically indicated and spontaneous preterm) are influenced by changes in prepregnancy body mass index (BMI) between the first and second pregnancies. A population-based, retrospective cohort analysis was performed using the Missouri (1978 to 2005) longitudinally linked cohort data sets. Women with their first two successive singleton live births ( N = 436,502) were analyzed. The risks for preterm birth and its subtypes were evaluated using multivariate logistic regression modeling. Compared with women who maintained normal interpregnancy BMI, women who lowered their weight from normal to underweight were more likely to experience preterm and spontaneous preterm birth (odds ratio [OR] 1.5, 95% confidence interval [CI] 1.4 to 1.6). Women with BMI changes from normal weight to obese (OR 1.4, 95% CI 1.2 to 1.6) and normal weight to overweight (OR 1.2, 95% CI 1.1 to 1.3) were at increased risk of medically indicated preterm birth. A decrease in prepregnancy BMI from normal to underweight is associated with increased risk of spontaneous preterm birth, and prepregnancy BMI increases from normal to overweight or to obese BMI are associated with increased risk of medically indicated preterm birth.

Younger maternal age (at initiation of childbearing) and recurrent perinatal mortality.

OBJECTIVE: To assess whether young maternal age at initiation of childbearing is associated with recurrence of perinatal mortality (PM), as well as its components: stillbirth and neonatal death. STUDY DESIGN: We conducted a population-based, retrospective cohort study on the Missouri maternally linked longitudinal data files comprising adolescent (10-19 years; n = 73,533) or mature (20-24 years; n = 78,618) mothers in their first pregnancy with follow-up in their second pregnancy to document the occurrence of PM or its components. The study covered the period 1989-2005. We used unconditional logistic regression modeling to generate odds ratios and to control for confounding. RESULTS: A history of perinatal mortality, stillbirth, or neonatal mortality increased the risk of a recurrence by 4-5 times. Among women with a history of PM or stillbirth in the first pregnancy, maternal age at initiation of pregnancy was not a risk factor for subsequent PM or its components. However, adolescent mothers with a history of neonatal mortality in the first pregnancy were about 5 times as likely to experience stillbirth in the second pregnancy, as compared to their mature counterparts. CONCLUSIONS: Young maternal age at the initiation of childbearing is not associated with an overall increased risk of recurrent perinatal loss. However, prior history of neonatal mortality among teen mothers is strongly predictive of subsequent stillbirth.