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Simple Summary: Oaks (Quercus spp.) are a major component of subtropical and temperate forests in the Northern Hemisphere. There are approximately 464 species, and they are dominant tree species in ecosystems. Oaks have a long history of cultivation in Europe, North America, and other continents. They are also cultivated and distributed in most provinces of China. In this paper, Quercus germplasm resource distribution, ecological adaptability, and utilization are explored. All evidence indicates that oaks have been widely distributed since ancient times and have greater functional value than other species in the Fagaceae family. This review will provide a deeper understanding of oak conservation, development, and utilization in China. Oaks exhibit unique biological characteristics and high adaptability to complex climatic and soil conditions. They are widely distributed across various regions, spanning 40 degrees latitude and 75 degrees longitude. The total area of oak forest in China is 16.72 million hm2. There are 60 lineages of Quercus in China, including 49 species, seven varieties, and four subgenera. Archaeological data indicate that oaks were already widely distributed in ancient times, and they are dominant trees in vast regions of China's forests. In addition, the acorn was an important food for ancestral humans, and it has accompanied human civilization since the early Paleolithic. Diverse oak species are widely distributed and have great functional value, such as for greening, carbon sequestration, industrial and medicinal uses, and insect rearing. Long-term deforestation, fire, diseases, and pests have led to a continuous decline in oak resources. This study discusses the Quercus species and their distribution in China, ecological adaptation, and the threats facing the propagation and growth of oaks in a changing world. This will give us a better understanding of Quercus resources, and provide guidance on how to protect and better utilize germplasm resources in China. The breeding of new varieties, pest control, and chemical and molecular research also need to be strengthened in future studies. [ABSTRACT FROM AUTHOR]

Background Passive-active immunoprophylaxis against mother-to-child transmission (MTCT) of hepatitis B virus (HBV) recommends administering hepatitis B immunoglobulin (HBIG) and birth-dose hepatitis B vaccine in infants within 12 or 24 hours after birth. With this protocol, MTCT of HBV still occurs in 5–10% infants of HBV-infected mothers with positive hepatitis B e antigen (HBeAg). The present study aimed to investigate whether earlier administration of HBIG and hepatitis B vaccine after birth can further increase protection efficacy. Methods We conducted a prospective, multi-center observational study in infants born to mothers with HBV infection, in whom neonatal HBIG and birth dose hepatitis B vaccine were administered within one hour after birth. The infants were followed up for HBV markers at 7–14 months of age. Results A total of 1140 pregnant women with HBV were enrolled, and 982 infants (9 twins) of 973 mothers were followed up at 9.6 ± 1.9 months of age. HBIG and birth-dose vaccine were administered in newborn infants within a median of 0.17 (0.02–1.0) hours after birth. The overall rate of MTCT was 0.9% (9/982), with none (0%) of the 607 infants of HBeAg-negative mothers and 9 (2.4%) of 375 infants of HBeAg-positive mothers acquiring HBV. All 9 HBV-infected infants were born to mothers with HBV DNA >2.75 × 106 IU/mL. Maternal HBV DNA levels >2 × 106 IU/mL were an independent risk factor (odds ratio, 10.627; 95% confidence interval, 2.135–∞) for immunoprophylaxis failure. Conclusions Earlier use (within 1 hour after birth) of HBIG and hepatitis B vaccine can provide better protection efficacy against MTCT of HBV. [ABSTRACT FROM AUTHOR]

Objectives: China has implemented universal hepatitis B vaccination since 2002 and provided charge-free hepatitis B immunoglobulin (HBIG) to infants of HBV-infected mothers since July 2011. We aimed to compare mother-to-child transmission (MTCT) in children born before and since July 2011. Methods: In total, 5,149 children of HBV-infected mothers were tested for HBV markers. Group one contained 1,160 children born during August 2002–June 2011 and group two contained 3,989 children born during July 2011–June 2016. Results: In total, 92 (1.8%, 95% confidence interval [95%CI] 1.4–2.2) children were infected with HBV. None (0%, 95%CI 0.0–0.1) of 3,716 children of mothers with negative hepatitis B e antigen (HBeAg) was infected, whereas 92 (6.4%, 95%CI 5.2–7.8) of 1,433 children of HBeAg-positive mothers were infected (p < 0.0001). Among children of HBeAg-positive mothers, MTCT occurred in 10.3% (19/185) (95%CI 6.3–15.6) in group one and 5.8% (73/1,248) (95%CI 4.6–7.3) in group two (p = 0.02). Conclusions: Implementing charge-free active-passive immunoprophylaxis greatly reduces MTCT of HBV in children of HBeAg-positive mothers, highlighting the importance of timely administration of both hepatitis B vaccine and HBIG to prevent MTCT. The still remaining MTCT suggests that reducing maternal virus load before delivery is an additional important measure. [ABSTRACT FROM AUTHOR]

Background: Pregnancy is a unique physiological condition with the cellular immune functions compromised at some extents to allow the mature of growing fetus. Whether pregnancy may influence the replication of hepatitis B virus (HBV) is less studied. The present study aimed to investigate the influence of pregnancy on the replication of HBV and expression of viral antigens by comparing the levels of HBV DNA and viral antigens in pregnant and non-pregnant women.Methods: A total of 727 HBsAg-positive serum samples, collected from 214 pregnant women and 513 non-pregnant women of childbearing age, were included. Based on the pregnancy status, subjects were divided into four groups: nulliparous (n = 158), pregnant (n = 214), 7-12 months postpartum (n = 170), and 2-5 years postpartum (n = 185). The levels of hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) were quantitatively measured with microparticle enzyme immunoassay. HBV DNA levels were detected by fluorescent real-time PCR.Results: The median ages of four groups were 25.0, 25.3, 26.2 and 29.3 years, respectively (p < 0.01). HBeAg-positive proportions were 34.2, 33.6, 35.3 and 29.2%, respectively (p = 0.624). HBV DNA levels in HBeAg-positive women were higher than those in HBeAg-negative women (7.88 vs 2.62 log IU/ml, p < 0.001). HBV DNA levels in the four groups with positive HBeAg were 7.8, 7.7, 8.0 and 8.0 log IU/ml, respectively (p = 0.057), while HBsAg titers were 4.4, 4.5, 4.6 and 4.8 log IU/ml (p = 0.086) and HBeAg titers were 3.1, 3.0, 3.1 and 3.0 log S/CO (p = 0.198). In the four groups with negative HBeAg, HBV DNA levels were 2.3, 2.6, 2.5 and 2.8 log IU/ml, respectively (p = 0.085), while HBsAg titers were 3.1, 3.3, 3.3 and 3.0 log IU/ml (p = 0.06).Conclusions: Serum levels of HBV DNA and viral antigens showed no significant changes in nulliparous, pregnant, and postpartum women, regardless of the HBeAg status. The results indicate that pregnancy has little influence on the replication of HBV and the expression of viral antigens. [ABSTRACT FROM AUTHOR]

Porous rocks are the source of important energy resources such as oil and gas that support development worldwide. The quantitative characterization of bound and movable fluid microdistribution is important for reservoir evaluation, productivity prediction, and petroleum recovery. However, due to the complexity of the fluid microdistribution in porous rocks, there is currently no effective method to achieve the continuous and quantitative characterization of the downhole or subsurface bound and movable fluid microdistribution. In this study, a method is proposed for the continuous and quantitative characterization of bound and movable fluid microdistribution in porous rocks based on nuclear magnetic resonance (NMR) measurements. First, 19 conventional sandstone samples collected from the Songliao Basin and 19 tight sandstone samples from the Ordos basin in China were evaluated using NMR experiments under fully water-saturated and bound water conditions and the transverse relaxation time (T 2) distributions of the saturated, bound, and movable water were obtained. Based on the findings from the NMR experiments, two exponential functions were proposed to quantitatively characterize the proportional coefficient distribution of the bound and movable fluids in pores of different sizes and to obtain the corresponding T 2 distributions of the bound and movable fluids. The effectiveness of the proposed method was verified by comparing the prediction results with the experimental results. Finally, the proposed method was extended into field applications in a tight sandstone reservoir in the Ordos Basin, China. The results of this study provide practical guidance for the exploration and development of oil and gas resources. • A fluid microdistribution characterization method in porous rocks was proposed. • Two exponential functions were used to characterize fluid proportions in pores. • The results are intuitive display of the bound and movable fluid microdistribution. • The proposed method provides guidance for further pore structure and seepage study. [ABSTRACT FROM AUTHOR]

Background: China discontinued the zero-COVID-19 policy on December 7, 2022, and then COVID-19 surged mid-December 2022 through mid-January 2023. However, the actual incidence was unknown. This study aimed to estimate the incidence of SARS-CoV-2 infection in children shortly after ending the zero-COVID-19 policy., Methods: This multicenter cross-sectional study included 1,065 children aged 8 months to 12 years from seven hospitals at six regions across Jiangsu province, based on the convenience sampling, from February 10 to March 10, 2023. Group I comprised 324 children aged 8 months-2 years without COVID-19 vaccination, group II consisted of 338 preschool children aged 3-5 years with varied vaccination history, and group III contained 403 primary school children aged 6-12 years with mostly vaccinated. The COVID-19 vaccines were composed of inactivated SARS-CoV-2. In addition, 96 children's sera collected in 2014 were included as negative controls. IgG and IgM antibodies against nucleocapsid (N) and subunit 1 of spike (S1) of SARS-CoV-2 (anti-N/S1) were measured with commercial kits (YHLO Biotech, Shenzhen, China)., Results: None of the 96 children (5.1 ± 3.5 years; 58.3% boys) in 2014 was positive for anti-N/S1 IgG or IgM. Of the 1,065 children (5.0 ± 3.5 years; 56.0% boys), 988 (92.8%) were anti-N/S1 IgG positive but none was anti-N/S1 IgM positive. The positive rate of anti-N/S1 IgG in Group I, II, and III was 90.4, 88.5, and 98.3%, respectively, with significantly higher in group III than in groups I and II ( p  < 0.0001). The median antibody titers in group III (381.61 AU/ml) were much higher than that in group I (38.34 AU/ml) and II (51.88 AU/ml; p  < 0.0001)., Conclusion: More than 90% children experienced SARS-CoV-2 infection shortly after ending zero-COVID-19 policy in China, much higher than estimated infections by other studies. The widespread SARS-CoV-2 infection in unvaccinated children should be influential on the policy of COVID-19 vaccination in children in the future., 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 © 2023 Zhou, Xu, Tao, Gu, Zhou, Zhou, Jin, Xie, Xu, Zhou, Chen and Shi.)

Background: We aimed to clarify whether presence of hepatitis B virus (HBV) markers in cord blood indicates exposure to or infection with HBV., Methods: We prospectively recruited HBsAg-positive pregnant women and their neonates 2012 through 2015. All neonates received postnatal immunoprophylaxis. The infants were followed up at 7-14 months of age., Results: Totally 329 HBsAg-positive pregnant women and 333 neonates were enrolled. No cord blood was anti-HBc IgM positive. A total of 290 (87.1%) neonates were followed up at 7-14 months of age and 6 (2.1%) of them were infected with HBV. Of 146 neonates born to HBeAg-negative mothers, 38 (26.0%) and 30 (20.5%) had detectable HBsAg and HBV DNA in cord blood respectively, but none of 126 infants followed up was infected. Of 187 neonates born to HBeAg-positive mothers, 92 (49.2%) and 79 (42.2%) had detectable HBsAg and HBV DNA in cord blood respectively; 6 (3.7%) of 164 infants followed up were infected. Of seven neonates with HBV DNA > 10 5  IU/ml in cord blood, four had no infection and three others were infected., Conclusion: Presence of HBsAg and/or HBV DNA, even at high levels, in cord blood just indicates exposure to, but not infection with HBV. Presence of HBV markers in cord blood cannot define intrauterine infection., (Copyright © 2018 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.)

The prevalence of occult Hepatitis B virus (HBV) infection in children was considerably varied from 0.1-64% in different reports. In this study we aimed to investigate the prevalence of occult HBV infection among the children born to mothers with positive hepatitis B surface antigen (HBsAg) in Jiangsu, China. Serum samples were collected from 210 children of 207 mothers with positive HBsAg. HBV serological markers were detected by ELISA and HBV DNA was detected by nested PCR. Homology comparison of HBV sequences recovered from the child and mother was used to define the infection. Three children (1.43%) were positive for HBsAg, in whom the HBV pre S and S gene sequence in each child was identical to that in her mother. Of the 207 HBsAg-negative children, nine displayed HBV DNA positive by two nested PCR assays using primers derived from S and C genes. However, the sequence alignment showed that the sequences in each child were considerably different from those in his/her mother. Therefore, the sequences amplified from the children were very likely resultant from the cross-contaminations. Furthermore, the nine children with 'positive HBV DNA' were all negative for anti-HBc, and one had anti-HBs 3.42 mIU/ml and eight others had anti-HBs from 72 to >1000 mIU/ml, indicating that the nine children were less likely infected with HBV. Therefore, none of the 207 HBsAg-negative children of HBV-infected mothers was found to have occult HBV infection. We conclude that the prevalence of occult HBV infection in vaccinated children born to HBsAg positive mothers should be extremely low. We recommend that homology comparison of sequences recovered from the child and mother be used to define the occult HBV infection in children born to HBV infected mothers.

Background: Many clinicians do not encourage breastfeeding in hepatitis B virus (HBV) carriers, since HBV DNA can be detected in breast milk and breast lesions may increase exposure of infants to HBV. The aim of this study was to determine whether breastfeeding may add risk for perinatal HBV transmission., Methodology/principal Findings: Totally 546 children (1-7-year-old) of 544 HBV-infected mothers were investigated, with 397 breastfed and 149 formula-fed; 137 were born to HBeAg-positive mothers. All children had been vaccinated against hepatitis B but only 53.3% received hepatitis B immune globulin (HBIG). The overall prevalence of HBsAg+, HBsAg-/anti-HBc+, and anti-HBs (≥10 mIU/ml) in children was 2.4%, 3.1%, and 71.6% respectively. The HBsAg prevalence in breast- and formula-fed children was 1.5% and 4.7% respectively (P = 0.063); the difference was likely due to the higher mothers' HBeAg-positive rate in formula-fed group (formula-fed 49.0% vs. breastfed 15.9%, P<0.001). Further logistic regression analyses showed that breastfeeding was not associated with the HBV infection in the children, adjusting for the effect of maternal HBeAg status and other factors different between the two groups., Conclusions/significance: Under the recommended prophylaxis, breastfeeding is not a risk factor for mother-to-child transmission of HBV. Therefore, clinicians should encourage HBV-infected mothers to breastfeed their infants.