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Iron Dextran is a widely used iron oxide compound to treat iron‐deficiency anemia patients in the clinic. Similar to other iron oxide compounds such as Ferumoxytol, it can also be used off‐label as an intravascular magnetic resonance imaging (MRI) contrast agent due to its strong iron‐induced T2 and T2* shortening effects. In this study, we seek to evaluate the feasibility of using Iron Dextran enhanced multi‐echo susceptibility weighted imaging (SWI) MRI at 7T to image arterial and venous blood vessels in the human brain. Phantom experiments were performed to measure the r2* relaxivity for Iron Dextran in blood, based on which the SWI sequence was optimized. Pre‐ and post‐infusion MR images were acquired in human subjects from which maps of arteries and veins were extracted. The post‐contrast SWI images showed enhanced susceptibility difference between blood and the surrounding tissue in both arteries and veins. Our results showed that the proposed Iron Dextran enhanced multi‐echo SWI approach allowed the visualization of blood vessels with diameters down to ~100 μm, including small blood vessels supplying and draining small brain structures such as the hippocampus. We conclude that Iron Dextran can be an alternative iron‐based MRI contrast agent for blood vessel imaging in the human brain. [ABSTRACT FROM AUTHOR]

Purpose: Acute gastroenteritis caused by Salmonella spp. among children post a great threat for global public health. The increasing rate of drug-resistant Salmonella spp. has also become a challenging problem worldwide. In this study, the prevalence, serotypes, and antimicrobial characteristics of Salmonella isolated from children in Guangzhou, China, were investigated to provide supporting information for clinical treatment and prevention. Methods: Clinical data of children featured with gastroenteritis symptoms from 2018 to 2023 in Guangdong Women and Children Hospital were collected. The difference and fluctuation of antimicrobial resistance between serotypes and years were retrospectively analyzed. Results: A total of 1304 Salmonella isolates were cultural-confirmed. The overall positive rate of Salmonella isolated from stool samples was 22.0% (1304/5924). Salmonella infections occur mainly from June to September and the majority of infected children aged under 4 years. Serogroup B was the most common serogroup among Salmonella isolates (74.6%, 973/1304). The predominant serotypes of Salmonella isolates were Typhimurium (63.1%, 823/1304). Higher drug resistance rate of Salmonella spp. to ceftriaxone was observed in 2023. The drug resistance rates of Salmonella isolates to sulfamethoxazole/trimethoprim and ampicillin are at high level during the past 6 years. Notably, higher multi-drug resistance (MDR) rate was demonstrated in Salmonella Typhimurium compared with other serotypes. Conclusion: Salmonella Typhimurium was the most common serotype isolated from children in Guangzhou, China, and it may mainly account for the high drug resistance rate in Salmonella spp. to most of the antimicrobial profiles. For controlling the high drug resistance rate of Salmonella spp. continuous surveillance of drug resistance and appropriate use of antibiotics based on clinical and laboratory results are of great significance. [ABSTRACT FROM AUTHOR]

Purpose: The inflow‐based vascular‐space‐occupancy (iVASO) MRI was originally developed in a single‐slice mode to measure arterial cerebral blood volume (CBVa). When vascular crushers are applied in iVASO, the signals can be sensitized predominantly to small pial arteries and arterioles. The purpose of this study is to perform a systematic optimization and evaluation of a 3D iVASO sequence on both 3 T and 7 T for the quantification of CBVa values in the human brain. Methods: Three sets of experiments were performed in three separate cohorts. (1) 3D iVASO MRI protocols were compared to single‐slice iVASO, and the reproducibility of whole‐brain 3D iVASO MRI was evaluated. (2) The effects from different vascular crushers in iVASO were assessed. (3) 3D iVASO MRI results were evaluated in arterial and venous blood vessels identified using ultrasmall‐superparamagnetic‐iron‐oxides–enhanced MRI to validate its arterial origin. Results: 3D iVASO scans showed signal‐to‐noise ratio (SNR) and CBVa measures consistent with single‐slice iVASO with reasonable intrasubject reproducibility. Among the iVASO scans performed with different vascular crushers, the whole‐brain 3D iVASO scan with a motion‐sensitized‐driven‐equilibrium preparation with two binomial refocusing pulses and an effective TE of 50 ms showed the best suppression of macrovascular signals, with a relatively low specific absorption rate. When no vascular crusher was applied, the CBVa maps from 3D iVASO scans showed large CBVa values in arterial vessels but well‐suppressed signals in venous vessels. Conclusion: A whole‐brain 3D iVASO MRI scan was optimized for CBVa measurement in the human brain. When only microvascular signals are desired, a motion‐sensitized‐driven‐equilibrium–based vascular crusher with binomial refocusing pulses can be applied in 3D iVASO. [ABSTRACT FROM AUTHOR]

Aims: The role of maternal genetic factors in the association between high glycated haemoglobin (HbA1c) levels and adverse birth outcomes remains unclear. Materials and Methods: In this study, the maternal HbA1c levels of 5108 normoglycemic pregnant women in China were measured, and A1298C and C677T polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene were genotyped. Results: Elevated HbA1c levels during the second trimester were associated with increased risks of macrosomia, large‐for‐gestational age (LGA), preterm birth (PTB), and reduced gestational age (p < 0.05). Pregnant women with MTHFR A1298C AA or C677T CT + TT genotypes were susceptible to adverse pregnancy outcomes related to HbA1c levels. Among pregnant women with the A1298C AA genotype, each standard deviation (SD) increase in HbA1c levels increased the risk of PTB by 1.32‐times and reduced the gestational age by 0.11 weeks (p < 0.05). For MTHFR C677T CC + TT genotype carriers, higher HbA1c levels were associated with 1.49‐, 1.24‐, and 1.23‐times increased risks of macrosomia, LGA, and PTB, respectively (p < 0.05). A U‐shaped curve for PTB risk in relation to HbA1c levels was observed among the C677T CC + TT participants, with a cut‐off value of 4.58%. Among subjects with the A1298C AA genotype combined with the C677T CT + TT genotype, each SD increase in HbA1c levels was associated with 1.40 and 1.37‐times increased risks of LGA and PTB, respectively. Conclusions: Our findings highlight the importance of glycaemic control during pregnancy and the potential impact of genetic factors on birth outcomes. However, further large‐scale studies are required to confirm these findings. [ABSTRACT FROM AUTHOR]

Background: Accumulating evidence has linked dyslipidemia during pregnancy to the risk of delivering infants born either large for gestational age (LGA) or small for gestational age (SGA). However, the effects of the vitamin D status on these relationships require further investigation. This study investigated whether the relationship between lipid profiles and the risk of LGA or SGA was influenced by vitamin D levels during the second trimester., Methods: Maternal lipid profile levels, including total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and vitamin D levels, were measured in a cohort of 6,499 pregnant women during the second trimester. Multivariate regression models and subgroup analyses were employed to evaluate the potential associations between maternal lipid profiles, vitamin D levels, and the risk of LGA or SGA., Results: The prevalence of SGA infants was 9.8% (n=635), whereas that of LGA infants was 6.9% (n=447). Maternal TG levels were found to be positively associated with the risk of LGA (odds ratio [OR] = 1.41, 95% confidence interval [CI]:1.17-1.70), whereas a negative association was observed between maternal TG, TC, LDL-C levels, and risk of SGA. Additionally, mothers with higher HDL-C levels were less likely to give birth to an LGA infant (OR=0.58, 95% CI:0.39-0.85). Importantly, associations between TG, TC, LDL-c, and SGA as well as between TG and LGA were primarily observed among pregnant women with insufficient vitamin D levels. As for HDL-C, the risk of LGA was lower in mothers with sufficient vitamin D (OR = 0.42, 95% CI:0.18-0.98) compared to those with insufficient vitamin D (OR = 0.65, 95% CI:0.42-0.99)., Conclusion: Vitamin D status during the second trimester exerts a modifying effect on the association between lipid profiles and the risk of LGA and SGA infants., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zheng, Lai, Liu, Chen, Zhang, Wu, Luo and Gu.)