[A multicenter study on respiratory pathogen detection with Mycoplasma pneumoniae pneumonia in children]

Objective: To analyze the status of respiratory pathogen detection and the clinical features in children with Mycoplasma pneumoniae pneumonia (MPP). Methods: A prospective, multicenter study was conducted to collect clinical data, including medical history, laboratory examinations and multiplex PCR tests of children diagnosed with MPP from 4 hospitals in China between November 15th and December 20th, 2023. The multiplex PCR results and clinical characteristics of MPP children in different regions were analyzed. The children were divided into severe and mild groups according to the severity of the disease. Patients in the severe group were further divided into Mycoplasma pneumoniae (MP) alone and Multi-pathogen co-detection groups based on whether other pathogens were detected besides MP, to analyze the influence of respiratory pathogen co-detection rate on the severity of the disease. Mann-Whitney rank sum test and Chi-square test were used to compare data between independent groups. Results: A total of 298 children, 136 males and 162 females, were enrolled in this study, including 204 children in the severe group with an onset age of 7.0 (6.0, 8.0) years, and 94 children in the mild group with an onset age of 6.5 (4.0, 7.8) years. The level of C-reactive protein, D-dimer, lactic dehydrogenase (LDH) were significantly higher (10.0 (5.0, 18.0) vs. 5.0 (5.0, 7.5) mg/L, 0.6 (0.4, 1.1) vs. 0.5 (0.3, 0.6) mg/L, 337 (286, 431) vs. 314 (271, 393) U/L, Z=2.02, 2.50, 3.05, all P<0.05), and the length of hospitalization was significantly longer in the severe group compared with those in mild group (6.0 (6.0, 7.0) vs. 5.0 (4.0, 6.0) d, Z=4.37, P<0.05). The time from onset to admission in severe MPP children was significantly shorter than that in mild MPP children (6.0 (5.0, 9.5) vs. 9.0 (7.0, 13.0) d, Z=2.23, P=0.026). All patients completed the multiplex PCR test, with 142 cases (47.7%) MPP children detected with 21 pathogens including adenovirus 25 cases (8.4%), human coronavirus 23 cases (7.7%), rhinovirus 21 cases (7.0%), Streptococcus pneumoniae 21 cases (7.0%), influenza A virus 18 cases (6.0%). The pathogens with the highest detection rates in Tianjin, Shanghai, Wenzhou and Chengdu were Staphylococcus aureus at 10.7% (8/75), adenovirus at 13.0% (10/77), adenovirus at 15.3% (9/59), and both rhinovirus and Haemophilus influenzae at 11.5% (10/87) each. The multi-pathogen co-detection rate in severe MPP children was significantly higher than that in mild MPP group (52.9% (108/204) vs. 36.2% (34/94), χ²=10.62,P=0.005). Among severe MPP children, there are 89 cases in the multi-pathogen co-detection group and 73 cases in the simple MPP group. The levels of LDH, D-dimer and neutrophil counts in the multi-pathogen co-detection group were significantly higher than those in the simple MPP group (348 (284, 422) vs. 307 (270, 358) U/L, 0.8 (0.5, 1.5) vs. 0.6 (0.4, 1.0) mg/L, 4.99 (3.66, 6.89)×109 vs. 4.06 (2.91, 5.65)×109/L, Z=5.17, 4.99, 6.11, all P<0.05). Conclusions: The co-detection rate of respiratory pathogens, LDH and D-dimer in children with severe MPP were higher than those with mild MPP. Among severe MPP children the stress response of children in co-detection group was more serious than that of children with simple MPP.

Exploring myometrial microenvironment changes at the single-cell level from nonpregnant to term pregnant states

The microenvironment and cell populations within the myometrium play crucial roles in maintaining uterine structural integrity and protecting the fetus during pregnancy. However, the specific changes occurring at the single-cell level in the human myometrium between nonpregnant (NP) and term pregnant (TP) states remain unexplored. In this study, we used single-cell RNA sequencing (scRNA-Seq) and spatial transcriptomics (ST) to construct a transcriptomic atlas of individual cells in the myometrium of NP and TP women. Integrated analysis of scRNA-Seq and ST data revealed spatially distinct transcriptional characteristics and examined cell-to-cell communication patterns based on ligand-receptor interactions. We identified and categorized 87,845 high-quality individual cells into 12 populations from scRNA-Seq data of 12 human myometrium tissues. Our findings demonstrated alterations in the proportions of five subpopulations of smooth muscle cells in TP. Moreover, an increase in monocytic cells, particularly M2 macrophages, was observed in TP myometrium samples, suggesting their involvement in the anti-inflammatory response. This study provides unprecedented single-cell resolution of the NP and TP myometrium, offering new insights into myometrial remodeling during pregnancy.NEW & NOTEWORTHY Using single-cell RNA sequencing and spatial transcriptomics, the myometrium was examined at the single-cell level during pregnancy. We identified spatially distinct cell populations and observed alterations in smooth muscle cells and increased M2 macrophages in term pregnant women. These findings offer unprecedented insights into myometrial remodeling and the anti-inflammatory response during pregnancy. The study advances our understanding of pregnancy-related myometrial changes.

Interaction Between Genetic Susceptibility and COVID-19 Pathogenesis in Pediatric Multisystem Inflammatory Disorders: The Role of Immune Responses

Numerous studies have highlighted the emergence of coronavirus disease (COVID-19) symptoms reminiscent of Kawasaki disease in children, including fever, heightened multisystem inflammation, and multiorgan involvement, posing a life-threatening complication. Consequently, extensive research endeavors in pediatric have aimed to elucidate the intricate relationship between COVID-19 infection and the immune system. COVID-19 profoundly impacts immune cells, culminating in a cytokine storm that particularly inflicts damage on the pulmonary system. The gravity and vulnerability to COVID-19 are closely intertwined with the vigor of the immune response. In this context, the human leukocyte antigen (HLA) molecule assumes pivotal significance in shaping immune responses. Genetic scrutiny of HLA has unveiled the presence of at least one deleterious allele in children afflicted with multisystem inflammatory syndrome in children (MIS-C). Furthermore, research has demonstrated that COVID-19 exploits the angiotensin-converting enzyme 2 (ACE-2) receptor, transmembrane serine protease type 2, and various other genes to gain entry into host cells, with individuals harboring ACE-2 polymorphisms being at higher risk. Pediatric studies have employed diverse genetic methodologies, such as genome-wide association studies (GWAS) and whole exome sequencing, to scrutinize target genes. These investigations have pinpointed two specific genomic loci linked to the severity and susceptibility of COVID-19, with the HLA locus emerging as a notable risk factor. In this comprehensive review article, we endeavor to assess the available evidence and consolidate data, offering insights into current clinical practices and delineating avenues for future research. Our objective is to advance early diagnosis, stabilization, and appropriate management strategies to mitigate genetic susceptibility's impact on the incidence of COVID-19 in pediatric patients with multisystem inflammation.

Photocatalytic Intramolecular Alkene Hydroamination of N-Alkoxy Ureas: An Approach to Imidazolinones

Imidazolinones were obtained in good yields by intramolecular hydroamination of N-alkoxy ureas in the presence of an organic photocatalyst and an inorganic base. In this reaction, the N-alkoxy urea anion generated by deprotonation undergoes photocatalyzed single-electron-transfer oxidation to generate the corresponding radical, which cyclizes to afford the imidazolinone ring. This new protocol grants access to an array of complex molecules containing a privileged imidazolinone core.

[Cardiovascular complications in malaria: a review]

Malaria, one of the major global public health events, is a leading cause of mortality and morbidity among children and adults in tropical and subtropical regions(mainly in sub-Saharan Africa), threatening human health. It is well known that malaria can cause various complications including anemia, blackwater fever, cerebral malaria, and kidney damage. Conventionally, cardiac involvement has not been listed as a common reason affecting morbidity and mortality of malaria, which may be related to ignored cases or insufficient diagnosis. However, the serious clinical consequences such as acute coronary syndrome, heart failure, and malignant arrhythmia caused by malaria have aroused great concern. At present, antimalarials are commonly used for treating malaria in clinical practice. However, inappropriate medication can increase the risk of cardiovascular diseases and cause severe consequences. This review summarized the research advances in the cardiovascular complications including acute myocardial infarction, arrhythmia, hypertension, heart failure, and myocarditis in malaria. The possible mechanisms of cardiovascular diseases caused by malaria were systematically expounded from the hypotheses of cell adhesion, inflammation and cytokines, myocardial apoptosis induced by plasmodium toxin, cardiac injury secondary to acute renal failure, and thrombosis. Furthermore, the effects of quinolines, nucleoprotein synthesis inhibitors, and artemisinin and its derivatives on cardiac structure and function were summarized. Compared with the cardiac toxicity of quinolines in antimalarial therapy, the adverse effects of artemisinin-derived drugs on heart have not been reported in clinical studies. More importantly, the artemisinin-derived drugs demonstrate favorable application prospects in the prevention and treatment of cardiovascular diseases, and are expected to play a role in the treatment of malaria patients with cardiovascular diseases. This review provides reference for the prevention and treatment of malaria-related cardiovascular complications as well as the safe application of antimalarials.

Impacts of air pollution and meteorological conditions on dry eye disease among residents in a northeastern Chinese metropolis: a six-year crossover study in a cold region

The purpose of this study is to explore the associations among dry eye disease (DED), air pollution, and meteorological conditions in the cold region of a northeastern Chinese metropolis (i.e., Changchun). Data on ambient air pollutants and meteorological parameters as well as diagnosed DED outpatients during 2015-2021 were collected. The associations between DED and environmental factors were analysed at multiple time scales using various statistical methods (i.e., correlation, regression and machine learning). Among the 10,809 DED patients (21,617 eyes) studied, 64.60% were female and 35.40% were male. A higher frequency of DED was observed in March and April, followed by January, August and October. Individual and multiple factor models showed the positive importance of particles with aerodynamic diameters <10 μm (PM₁₀), carbon monoxide (CO), and ozone (O₃) among normal air pollutants and air pressure (AP), air temperature (AT) and wind speed (WS) among normal meteorological parameters. Air pollutants (PM₁₀, nitrogen dioxide: NO₂) and meteorological parameters (AT, AP) have combined impacts on DED occurrence. For the first time, we further explored the associations of detailed components of atmospheric particles and DED, suggesting potential emission sources, including spring dust from bare soil and roads and precursor pollutants of summer O₃ formation from vehicles and industry in Northeast China. Our results revealed the quantitative associations among air pollutants, meteorological conditions and DED outpatients in cold regions, highlighting the importance of coordinated policies in air pollution control and climate change mitigation.

CDKN1C gene mutation causing familial Silver–Russell syndrome: A case report and review of literature

BACKGROUND

Cyclin-dependent kinase inhibitor 1C (CDKN1C) is a cell proliferation inhibitor that regulates the cell cycle and cell growth through G1 cell cycle arrest. CDKN1C mutations can lead to IMAGe syndrome (CDKN1C allele gain-of-function mutations lead to intrauterine growth restriction, metaphyseal dysplasia, adrenal hypoplasia congenital, and genitourinary malformations). We present a Silver-Russell syndrome (SRS) pedigree that was due to a missense mutation affecting the same amino acid position, 279, in the CDKN1C gene, resulting in the amino acid substitution p.Arg279His (c.836G>A). The affected family members had an SRS phenotype but did not have limb asymmetry or adrenal insufficiency. The amino acid changes in this specific region were located in a narrow functional region that contained mutations previously associated with IMAGe syndrome. In familial SRS patients, the PCNA region of CDKN1C should be analysed. Adrenal insufficiency should be excluded in all patients with functional CDKN1C variants.

CASE SUMMARY

We describe the case of an 8-year-old girl who initially presented with short stature. Her height was 91.6 cm, and her weight was 10.2 kg. Physical examination revealed that she had a relatively large head, an inverted triangular face, a protruding forehead, a low ear position, sunken eye sockets, and irregular cracked teeth but no limb asymmetry. Family history: The girl’s mother, great-grandmother, and grandmother’s brother also had a prominent forehead, triangular face, and severely proportional dwarfism but no limb asymmetry or adrenal insufficiency. Exome sequencing of the girl revealed a new heterozygous CDKN1C (NM_000076. 2) c.836G>A mutation, resulting in a variant with a predicted evolutionarily highly conserved arginine substituted by histidine (p.Arg279His). The same causative mutation was found in both the proband’s mother, great-grandmother, and grandmother’s brother, who had similar phenotypes. Thus far, we found an SRS pedigree, which was due to a missense mutation affecting the same amino acid position, 279, in the CDKN1C gene, resulting in the amino acid substitution p.Arg279His (c.836G>A). Although the SRS-related CDKN1C mutation is in the IMAGe-related mutation hotspot region [the proliferating cell nuclear antigen (PCNA) domain], no adrenal insufficiency was reported in this SRS pedigree. The reason may be that the location of the genomic mutation and the type of missense mutation determines the phenotype. The proband was treated with recombinant human growth hormone (rhGH). After 1 year of rhGH treatment, the height standard deviation score of the proband increased by 0.93 standard deviation score, and her growth rate was 8.1 cm/year. No adverse reactions, such as abnormal blood glucose, were found.

CONCLUSION

Functional mutations in CDKN1C can lead to familial SRS without limb asymmetry, and some patients may have glucose abnormalities. In familial SRS patients, the PCNA region of CDKN1C should be analysed. Adrenal insufficiency should be excluded in all patients with functional CDKN1C variants.

Molecular epidemiology analysis of symptomatic and asymptomatic norovirus infections in Chinese infants

BACKGROUND

Norovirus is a leading cause of acute gastroenteritis among children. Previous studies based on symptomatic infections indicated that mutations, rather than recombination drove the evolution of the norovirus ORF2. These characteristics were found in hospital-based symptomatic infections, whereas, asymptomatic infections are frequent and contribute significantly to transmission.

METHODS

We conducted the first norovirus molecular epidemiology analysis covering both symptomatic and asymptomatic infections derived from a birth cohort study in the northern China.

RESULTS

During the study, 14 symptomatic and 20 asymptomatic norovirus infections were detected in 32 infants. Out of the 14 strains that caused symptomatic infections, 12 strains were identified as GII.3[P12], and others were GII.4[P31]. Conversely, 17 asymptomatic infections were caused by GII.4[P31], two by GII.2[P16], and one by GII.4[P16]. Regardless of symptomatic and asymptomatic infections, the mutations were detected frequently in the ORF2 region, and almost all recombination were identified in the RdRp-ORF2 region. The majority of the mutations were located around the predefined epitope regions of P2 subdomain indicating a potential for immune evasion.

CONCLUSION

The role of symptomatic as well as asymptomatic infections in the evolution of norovirus needs to be evaluated continuously.

[Two cases of airway dysfunction related to diacetyl exposure]

Occupational exposure to diacetyl can lead to bronchiolitis obliterans. In this paper, two patients with severe obstructive ventilation disorder who were exposed to diacetyl at a fragrance and flavours factory were analyzed. The clinical manifestations were cough and shortness of breath. One of them showed Mosaic shadows and uneven perfusion in both lungs on CT, while the other was normal. Field investigation found that 4 of the 8 workers in the factory were found to have obstructive ventilation disorder, and 2 had small airway dysfunction. This paper summarizes the diagnostic process of patients in order to improve the understanding of airway dysfunction caused by occupational exposure to diacetyl and promote the development of relevant standards.

Damage of brown planthopper (BPH) Nilaparvata lugens and rice leaf folder (LF) Cnaphalocrocis medinalis in parent plants lead to distinct resistance in ratoon rice

Herbivore-induced defense responses are often specific, whereas plants could induce distinct defense responses corresponding to infestation by different herbivorous insects. Brown plant hopper (BPH) Nilaparvata lugens, a phloem-feeding insect, and rice leaf folder (LF) Cnaphalocrocis medinalis, a chewing insect, are both specialist herbivores on rice. To characterize the distinct resistance primed by prior damage to these two specialist herbivores, we challenged rice plants with two herbivores during vegetative growth of parent plants and assessed plant resistance in subsequent ratoons. Here, we show that LF and BPH induce different suites of defense responses in parent rice plants, LF induced higher level of JA accumulation and OsAOS, OsCOI1 transcripts, while BPH induced higher accumulation of SA and OsPAL1 transcripts. Moreover, an apparent loss of LF resistance was observed in OsAOS, OsCOI1 RNAi lines. Ratoon plants generated from parents receiving prior LF infestation exhibited higher jasmonic acid (JA) levels and elevated levels of transcripts of defense-related genes associated with JA signaling, while ratoon generated from parents receiving prior BPH infestation exhibited higher salicylic acid (SA) levels and elevated levels of transcripts of defense-related genes associated with SA signaling. Moreover, previous LF infestation obviously elevated ratoons resistance to LF, while previous infestation by BPH led to enhanced resistance in ratoons to BPH. Pre-priming of ratoons defense to LF was significantly reduced in OsAOS and OsCOI1 RNAi plant, but silencing OsAOS and OsCOI1 did not attenuate ratoons resistance to BPH. These results suggest that infestation of two specialist herbivores with different feeding styles in parent crop led to distinct defense responses in subsequent rations, and the acquired resistance to LF in ratoons is associated with priming of jasmonic acid-dependent defense responses.

[Pharmacodynamic substances and therapeutic potential of Wuji Pills:based on UPLC-Q-TOF-MS/MS and network pharmacology]

As a classic prescription, Wuji Pills is composed of Coptidis Rhizoma, Euodiae Fructus Preparata, and stir-fried Paeo-niae Radix Alba at the ratio of 6∶1∶6. The practical application of it is limited compared with other famous Chinese medicine prescriptions. Only one company produces Wuji Pills in China. In this study, ultra-performance liquid chromatography quadrupole time of flight mass spectrometry(UPLC-Q-TOF-MS/MS) was used to analyze and identify 26 identical compounds from Wuji Pills and drug-containing plasma of rats. Based on these components, 46 potential targets were screened out with network pharmacology methods, followed by the component-target network construction, Gene Ontology(GO) term enrichment, Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment, and disease prediction. It was concluded that Wuji Pills acted on core targets such as PTGS2, PTSG1, NCOA2, HSP9 OAD1, and RXRA through magnoflorine, hydroxyevodiamine, daucosterol, and berberine and exerted pharmacodynamic effects through various pathways such as calcium ion signaling pathway, phosphatidylinositol-3-kinase-protein kinase B(PI3 K-Akt) signaling pathway, and vascular endothelial growth factor(VEGF) signaling pathway. Thus, Wuji Pills has therapeutic potential for Alzheimer's disease, diabetes mellitus, myocardial ischemia, and other diseases in addition to the conventional disease(irritable bowel syndrome, IBS). The above research results can provide a reference for the comprehensive interpretation of the pharmacodynamic basis of Wuji Pills and the expansion of clinical application. At the same time, a lot of components in serum and the in vivo transformed and metabolized components of Wuji Pills have similar structure and relative molecular weight. In theory, these components may show additive effects and the competitive/antagonistic effects on the same target. According to the hypothesis of &quot;additive effect of multiple components for a single target&quot; in traditional Chinese medicine, multiple similar components may exert the additive effects on local targets. This study can partly prove the scientificity of this hypothesis and provide laboratory evidence.

Identification and functional analysis of novel SOX11 variants in Chinese patients with Coffin-Siris syndrome 9

SOX11 is a transcription factor belonging to the sex determining region Y-related high-mobility group box family that plays a vital role in early embryogenesis and neurogenesis. De novo variants in SOX11 have been initially reported to cause a rare neurodevelopmental disorder, mainly referred to Coffin-siris syndrome 9 (CSS9, OMIM# 615866) which is characterized with growth deficiency, intellectual disability (ID), microcephaly, coarse facies, and hypoplastic nails of the fifth fingers and/or toes. A recent large-scale cohort study suggests that SOX11 variation would result in a clinically and molecularly distinct disease from CSS. Here, we describe three unrelated Chinese cases with variable phenotype, mainly involving developmental delay, ID, short statute, microcephaly, facial deformities (i.e., prominent forehead, arched eye brow, flat nasal bridge, broad nose and short philtrum), and cryptorchidism. Whole-exome sequencing (WES) revealed three novel heterozygous variants in the SOX11 gene, including two missense variants of c.337T>C (p.Y113H) and c.425C>G (p.A142G), and one nonsense variant of c.820A>T (p. K142*). Luciferase reporting assay shows that the two missense variants impair the transcriptional activity of the SOX11 target gene GDF5. Additionally, WES uncovered a 4,300 kb deletion involving the region of 1q24.2-q25.1 (hg19,chr1:169,433,149-173,827,682) in patient 1, which also contributes to the condition of the patient. In summary, this is the first report of Chinese cases with de novo variants of SOX11. Our study partially supports the previous observation that the phenotype caused by SOX11 variants somewhat differs from classical CSS.

A 7-year-old boy with recurrent cyanosis and tachypnea: A case report

BACKGROUND

Brain tumors are the most common solid tumors in children and comprise 25% of all malignancies in children. Common presentations include headache, nausea and vomiting, gait abnormality, papilledema, and epileptic seizure; however, some symptoms can be very insidious, with atypical and misleading manifestations.

CASE SUMMARY

Here, we report a 7-year-old boy who presented with recurrent cyanosis and tachypnea after exercise for 2 years. His body mass index was 26.43 kg/m². Hepatosplenomegaly, blood gas analysis, biochemical parameters, chest computed tomography scan, and echocardiograph suggested type II respiratory failure, pulmonary heart disease, and mild liver injury. Non-invasive breathing support, antibiotics, and anti-heart failure therapy were given. The patient’s pulse oxygen saturation increased to over 95% when he was awake but dropped to 50%-60%, accompanied by cyanosis, during sleep while receiving high-flow nasal cannula oxygen. Sleep-related breathing disorder was suspected. In the intensive care unit, however, polysomnography was unavailable. Brain magnetic resonance imaging revealed a space-occupying (cerebellum and brainstem) lesion, which was later confirmed to be pleomorphic xanthoastrocytoma by surgery and histopathology by tissue biopsy.

CONCLUSION

When treating patients with cyanosis and tachypnea, a broad differential diagnosis should be considered, including brain tumor.

Genetic characterization of two G8P[8] rotavirus strains isolated in Guangzhou, China, in 2020/21: evidence of genome reassortment

Background

The G8 rotavirus genotype has been detected frequently in children in many countries and even became the predominant strain in sub-Saharan African countries, while there are currently no reports from China. In this study we described the genetic characteristics and evolutionary relationship between rotavirus strains from Guangzhou in China and the epidemic rotavirus strains derived from GenBank, 2020–2021.

Methods

Virus isolation and subsequent next-generation sequencing were performed for confirmed G8P[8] specimens. The genetic characteristics and evolutionary relationship were analyzed in comparison with epidemic rotavirus sequences obtained from GenBank.

Results

The two Guangzhou G8 strains were DS-1-like with the closest genetic distance to strains circulating in Southeast Asia. The VP7 genes of the two strains were derived from a human, not an animal G8 rotavirus. Large genetic distances in several genes suggested that the Guangzhou strains may not have been transmitted directly from Southeast Asian countries, but have emerged following reassortment events.

Conclusions

We report the whole genome sequence information of G8P[8] rotaviruses recently detected in China; their clinical and epidemiological significance remains to be explored further.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07542-9.

Pulmonary lymphomatoid granulomatosis in a 4-year-old girl: A case report

BACKGROUND

Pulmonary lymphomatoid granulomatosis (PLG) is a lymphoproliferative disease associated with Epstein-Barr viral infection occurring mainly in adults and rarely in children. It is characterized by multiple pulmonary nodules. Its diagnosis depends on lung biopsy findings. Most patients are immunodeficient, and it commonly presents in children undergoing chemotherapy for leukemia. We report the case of a child with PLG caused by a mutation in the macrophage-expressed gene 1 (MPEG1), suggesting possible PLG occurrence in children undergoing treatment for pulmonary nodular lesions.

CASE SUMMARY

This study reports a case of PLG without apparent immunodeficiency, suggesting the possibility of this disease occurrence during the treatment of pulmonary nodular lesions in children. Initially, the cause was assumed to be an atypical pathogen. Following conventional anti-infective treatment, chest computed tomography findings revealed that there were still multiple nodules in the lungs. Additionally, the patient was found to be infected with the Epstein-Barr virus. Histopathological examination of the resected lung revealed lymphoproliferative lesions with necrosis. Small lymphocytes, plasma cells, and histiocytes were observed in the background, although Reed-Sternberg cells were absent. Immunohistochemical staining [CD20(+), CD30(+), and CD3(+)] and EBV-encoded small RNA1/2 in situ hybridization of small lymphocytes revealed approximately 200 cells/high-power field. Whole exon sequencing of the patient revealed a mutation in the MPEG1. The patient was eventually diagnosed with PLG and transferred to the Department of Pediatric Oncology for bone marrow transplantation.

CONCLUSION

As PLG is rare and fatal, it should be suspected in clinical settings when treatment of initial diagnosis is ineffective.

High CO-Tolerant Ru-Based Catalysts by Constructing an Oxide Blocking Layer

CO poisoning of Pt-group metal catalysts is a long-standing problem, particularly for hydrogen oxidation reaction in proton exchange membrane fuel cells. Here, we report a catalyst of Ru oxide-coated Ru supported on TiO₂ (Ru@RuO₂/TiO₂), which can tolerate 1-3% CO, enhanced by about 2 orders of magnitude over the classic PtRu/C catalyst, for hydrogen electrooxidation in a rotating disk electrode test. This catalyst can work stably in 1% CO/H₂ for 50 h. About 20% of active sites can survive even in a pure CO environment. The high CO tolerance is not via a traditional bifunctional mechanism, i.e., oxide promoting CO oxidation, but rather via hydrous metal oxide shell blocking CO adsorption. An ab initio molecular dynamics (AIMD) simulation indicates that water confined in grain boundaries of the Ru oxide layer and Ru surface can suppress the diffusion and adsorption of CO. This oxide blocking layer approach opens a promising avenue for the design of high CO-tolerant electrocatalysts for fuel cells.

Visible light-induced N-radical 5-exo/6-endo cyclization of alkenyl amides: facile access to isoindolinones/isoquinolinones

An efficient N-centered radical intramolecular cyclization reaction of alkenyl amides induced by visible light was described. In this process, an alkenyl amide underwent 5-exo/6-endo cyclization to selectively yield two critical alkaloid structures, namely isoindolinones and isoquinolinones.

[A multicenter retrospective study on the etiology of necrotizing pneumonia in children]

Objective: To investigate the etiology of necrotizing pneumonia (NP) in children and the clinical characteristics of NP caused by different pathogens in China. Methods: A retrospective, case-control study was performed in children with NP who were admitted to 13 hospitals in China from January 2008 to December 2019. The demographic and clinical information, laboratory data, etiological and radiological findings were analyzed. The data were divided into three groups based on the following years: 2008-2011, 2012-2015 and 2016-2019, and the distribution characteristics of the pathogens in different period were compared. Meanwhile, the pathogens of pediatric NP in the southern and northern China were compared. And the clinical characteristics of the Mycoplasma pneumoniae (MP) NP and the bacterial NP were also compared. T-test or Mann-Whitney nonparametric test was used for comparison of numerical variables, and χ² test was used for categorical variables. Results: A total of 494 children with NP were enrolled, the median ages were 4.7 (0.1-15.3) years, including 272 boys and 222 girls. Among these patients, pathogens were identified in 347 cases and the pathogen was unclear in the remaining 147 cases. The main pathogens were MP (238 cases), Streptococcus pneumoniae (SP) (61 cases), Staphylococcus aureus (SA) (51 cases), Pseudomonas aeruginosa (13 cases), Haemophilus influenzae (10 cases), adenovirus (10 cases), and influenza virus A (7 cases), respectively. MP was the most common pathogen in all three periods and the proportion increased yearly. The proportion of MP in 2016-2019 was significantly higher than that in 2012-2015 (52.1% (197/378) vs. 36.8% (32/87), χ²=6.654, P=0.010), while there was no significant difference in the proportion of MP in 2012-2015 and that in 2008-2011 (36.8% (32/87) vs. 31.0% (9/29), χ²=0.314, P=0.575).Regarding the regional distribution, 342 cases were in the southern China and 152 in the northern China. Also, MP was the most common pathogen in both regions, but the proportion of MP was higher and the proportion of SP was lower in the north than those in the south (60.5% (92/152) vs. 42.7% (146/342), χ²=13.409, P<0.010; 7.9% (12/152) vs. 14.3% (49/342), χ²=4.023, P=0.045). Comparing the clinical characteristics of different pathogens, we found that fever and cough were the common symptoms in both single MP and single bacterial groups, but chest pain was more common (17.0% (34/200) vs. 6.1% (6/98), χ²=6.697, P=0.010) while shortness of breath and wheezing were less common in MP group (16.0% (32/200) vs. 60.2% (59/98), χ²=60.688, P<0.01; 4.5% (9/200) vs. 21.4% (21/98), χ²=20.819, P<0.01, respectively). The white blood cell count, C-reactive protein and procalcitonin in the bacterial group were significantly higher than those in the MP group (14.7 (1.0-67.1)×10⁹/L vs. 10.5 (2.5-32.2)×10⁹/L, 122.5 (0.5-277.3) mg/L vs. 51.4 (0.5-200.0) g/L, 2.13 (0.05-100.00) μg/L vs. 0.24 (0.01-18.85) μg/L, Z=-3.719, -5.901 and -7.765, all P<0.01). Conclusions: The prevalence of pediatric NP in China shows an increasing trend during the past years. MP, SP and SA are the main pathogens of NP, and the most common clinical symptoms are fever and cough. The WBC count, C-reactive protein and procalcitonin in bacterial NP are significantly higher than those caused by MP.

Resveratrol acts via melanoma-associated antigen A12 (MAGEA12)/protein kinase B (Akt) signaling to inhibit the proliferation of oral squamous cell carcinoma cells

The present study examined how resveratrol affects cell growth and MAGEA12/Akt signaling pathway in OSCC cells. Cal-27 cells were transiently transfected with a plasmid encoding MAGEA12, and the effects of overexpression were assessed in terms of cell viability, colony formation and the epithelial–mesenchymal transition. Cal-27 cells and MAGEA12-overexpressing cells were treated with resveratrol, then the cell viability and colony formation were also assessed by CCK8 assay and microscope, respectively. Levels of MAGEA12, p-Akt, Akt, Cyclin D1, and CDK14 genes and these proteins were analyzed using quantitative reverse-transcription polymerase-chain reaction and western blot. In the present research, we first generated and transiently transfected MAGEA12 plasmid into Cal-27 cells. Our results suggested that overexpressing MAGEA12 led to an increase in levels of phospho-Akt, which was associated with increased cell viability, colony formation. Moreover, overexpressing MAGEA12 also resulted in the up-regulation of Cyclin D1 and CDK14, indicating MAGEA12 induces the cell proliferation of Cal-27 cells. In addition, these effects were partially reversed by inhibiting Akt. Furthermore, resveratrol could inhibit the proliferation and colony in Cal-27 cells and decrease the expressions of MAGEA12 and p-Akt depending on the time and concentration. These effects were also partially reversed by MAGEA12 overexpression and Akt activation. In summary, resveratrol may suppress the growth of OSCC cells by inactivating MAGEA12/Akt signaling. These findings suggest that resveratrol may be a therapeutic drug for OSCC in clinical.

[Potential therapies for COVID-19 cardiovascular complications using artemisinin and its derivatives intervene based on its cardiovascular protection]

Corona virus disease 2019(COVID-19) has brought untold human sufferings and economic tragedy worldwide. It causes acute myocardial injury and chronic damage of cardiovascular system, which has attracted much attention from researchers. For the immediate strategy for COVID-19, &quot;drug repurposing&quot; is a new opportunity for developing drugs to fight COVID-19. Artemisinin and its derivatives have a wide range of pharmacological activities. Recent studies have shown that artemisinin has clear cardiovascular protective effects. This paper summarizes the research progress on the pathogenesis the pathogenesis of COVID-19 in cardiovascular damage by 2019 novel coronavirus(2019-nCoV) virus from myocardial cell injury directly by 2019-nCoV virus,viral ligands competitively bind to ACE2 and then reduce the protective effect of ACE2 on cardiovascular disease, &quot;cytokine storm&quot; related myocardial damage, arrhythmia and sudden cardiac death induced by the infection and stress, myocardial injury by hypoxemia, heart damage side effects from COVID-19 drugs and summarizing the cardiovascular protective effects of artemisinin and its derivatives have activities of anti-arrhythmia, anti-myocardial ischemia, anti-atherosclerosis and plaque stabilization. Then analyzed the possible multi-pathway intervention effects of artemisinin-based drugs on multiple complications of COVID-19 based on its specific immunomodulatory effects, protective effects of tissue and organ damage and broad-spectrum antiviral effect, to provide clues for the treatment of cardiovascular complications of COVID-19, and give a new basis for the therapy of COVID-19 through &quot;drug repurposing&quot;.

Genetic susceptibility to rotavirus infection in Chinese children: a population-based case-control study

Rotaviruses (RVs) are the leading cause of acute gastroenteritis in children, while histo-blood group antigens (HBGAs) are believed to be host attachment and susceptibility factors of RVs. A large case-control study nested in a population-based diarrhea surveillance targeting children <5 y of age was performed in rural Hebei province, north China. Saliva and serum samples were collected from all participants to determine HBGA phenotyping, FUT2 mutations, and RV IgG antibody titers. A logistic model was employed to assess the association between host HBGA secretor status and risk of RV infection. Among 235 RV cases and 680 non-diarrhea controls studied, 82.4% of participants were IgG positive by an average age of 77 months. Out of the 235 RV cases, 216 (91.9%) were secretors, whereas the secretor rate was 76.3% in the non-diarrhea controls, resulted in an adjusted OR of 3.0 (95%CI: 1.9-4.7, P < .0001) between the two groups. Our population-based case-control study indicated a strong association between host HBGA secretor status and risk of RV infection in Chinese children. The high prevalence of Lewis-positive secretor status strongly suggests that Chinese children may be genetically susceptible to current co-circulating RV strains, and thus, a universal childhood immunization program against RV disease should be successful in China.

[Association of age distribution with the expression of angiotensin-converting enzyme 2 in lung tissues in severe acute respiratory syndrome coronavirus 2 infection: reflections from the study of RAS pathway expression in mice]

OBJECTIVE

To study the expression of angiotensin-converting enzyme 2 (ACE2) and other key molecules of the RAS pathway in normal mice at different developmental stages, and to provide ideas for understanding the infection mechanism of coronavirus disease 2019 (COVID-19) as well as the diagnosis and treatment of children with COVID-19.

METHODS

The mice at different developmental stages were enrolled, including fetal mice (embryonic days 14.5 and 18.5), neonatal mice (0, 3, 7, 14, and 21 days old), young mice (28 and 42 days old), and adult mice (84 days old). The lung tissues of all fetal mice from 4 pregnant mice were collected at each time point in the fetal group. Four mice were sampled in other age groups at each time point. Whole transcriptome resequencing was used to measure the mRNA expression of AGT, ACE, ACE2, Renin, Agtr1a, Agtr1b, Agtr2, and Mas1 in mouse lung tissue.

RESULTS

The expression of ACE2 in the lungs showed changes from embryonic stage to adult stage. It increased gradually after birth, reached a peak on day 3 after birth, and reached a nadir on day 14 after birth (P<0.05). The expression of AGT reached a peak on days 0 and 7 after birth and reached a nadir on day 21 after birth (P<0.05). The expression of ACE increased rapidly after birth and reached a peak on day 21 after birth (P<0.05). Agtr1a expression reached a peak on day 21 after birth (P<0.05). Agtr2 expression gradually decreased to a low level after birth. Renin, Agtr1b, and Mas1 showed low expression in lung tissues at all developmental stages.

CONCLUSIONS

At different developmental stages of mice, ACE2 has dynamic expression changes, with high expression in early neonatal and adult mice. The other key molecules of the RAS pathway have their own expression patterns. These suggest that the difference in clinical features between children and adults with COVID-19 might be associated with the different expression levels of ACE2 in the different stages, and further studies are needed for the mechanism.

[Association of age distribution with the expression of angiotensin-converting enzyme 2 in lung tissues in severe acute respiratory syndrome coronavirus 2 infection: reflections from the study of RAS pathway expression in mice]

OBJECTIVE

To study the expression of angiotensin-converting enzyme 2 (ACE2) and other key molecules of the RAS pathway in normal mice at different developmental stages, and to provide ideas for understanding the infection mechanism of coronavirus disease 2019 (COVID-19) as well as the diagnosis and treatment of children with COVID-19.

METHODS

The mice at different developmental stages were enrolled, including fetal mice (embryonic days 14.5 and 18.5), neonatal mice (0, 3, 7, 14, and 21 days old), young mice (28 and 42 days old), and adult mice (84 days old). The lung tissues of all fetal mice from 4 pregnant mice were collected at each time point in the fetal group. Four mice were sampled in other age groups at each time point. Whole transcriptome resequencing was used to measure the mRNA expression of AGT, ACE, ACE2, Renin, Agtr1a, Agtr1b, Agtr2, and Mas1 in mouse lung tissue.

RESULTS

The expression of ACE2 in the lungs showed changes from embryonic stage to adult stage. It increased gradually after birth, reached a peak on day 3 after birth, and reached a nadir on day 14 after birth (P<0.05). The expression of AGT reached a peak on days 0 and 7 after birth and reached a nadir on day 21 after birth (P<0.05). The expression of ACE increased rapidly after birth and reached a peak on day 21 after birth (P<0.05). Agtr1a expression reached a peak on day 21 after birth (P<0.05). Agtr2 expression gradually decreased to a low level after birth. Renin, Agtr1b, and Mas1 showed low expression in lung tissues at all developmental stages.

CONCLUSIONS

At different developmental stages of mice, ACE2 has dynamic expression changes, with high expression in early neonatal and adult mice. The other key molecules of the RAS pathway have their own expression patterns. These suggest that the difference in clinical features between children and adults with COVID-19 might be associated with the different expression levels of ACE2 in the different stages, and further studies are needed for the mechanism.

[Method for rapid synchronization of different growth cycles of Plasmodium falciparum in vitro and application in differential gene expression profile of 3D7 after dihydroartemisinin treatment]

Plasmodium culture in vitro is often used as an antimalarial drug evaluation model, but the lifecycle of P. falciparum culture in vitro tends to be disordered, which affects the research and evaluation of antimalarial drug mechanism in vitro. By combining magnetic bead separation method with sorbitol synchronization method, a synchronization method was constructed to quickly acquire different lifecycles of P. falciparum and obtain large amounts of parasite with a narrow synchronization window in a short period. Furthermore, the dihydroartemisinin(DHA) was used to treat the early trophozoite phase of P. falciparum 3 D7 for 4 h. Then mRNA was extracted and RNA-seq was conducted to analyze the differential expression of mRNA after drug treatment and obtain the differential gene expression profile. Differential expression of up-regulated genes and down-regulated genes was analyzed according to the screening criteria of |log_2FC|&gt;1 and P&lt;0.05. There, 262 genes were up-regulated and 77 genes were down-regulated. GO functional enrichment analysis of all the differentially expressed genes showed that the enrichment items mainly included cell membrane components, transporter activity, serine/threonine kinase activity, Maurer's clefts(MCs), rhoptry, antigen variation and immune evasion. The enrichment of KEGG pathway included malaria, fatty acid metabolism and peroxisome. Protein-protein interaction(PPI) analysis showed that the down-regulated genes in the modules with high degree of association included rhoptry, myosin complex, transporter and other genes related to the important life activities of malaria invasion and immune escape; the up-regulated genes were mainly related to various toxic exportins of malaria, such as PfSBP1 of MCs. qRT-PCR was used to verify the expression level of some genes, and most of the results were the same as the sequencing results. SBP1 was significantly up-regulated, while some antigenic protein expression levels were down-regulated. Above all, key molecules of DHA therapy were mainly involved in the parasites' rhoptry, transporter, antigenic variation, plasmodium exportin. These results offer us many hints to guide the further studies on mechanism of artemisinin and provide a new way for development of new antimalarial drugs.

Genetic Analysis of Four Sexual Differentiation Process Proteins (isp4/SDPs) in Chaetomium thermophilum and Thermomyces lanuginosus Reveals Their Distinct Roles in Development

Fungal sexual development requires the involvement of a large number of functional genes. Fungal genes encoding sexual differentiation process proteins (SDPs), isps, have been known for decades. isp4/SDP and its homologs function as oligopeptide transporters (OPTs), yet their roles in reproduction are unknown. Here, we genetically analyzed all four isp4/SDP homologs in the sexual species Chaetomium thermophilum and asexual species Thermomyces lanuginosus. Using single gene deletion mutants, we found that T. lanuginosus SDP (TlSDP) participated in asexual sporulation, whereas the other homologs participated in sexual morphogenesis. In complementary tests, C. thermophilum SDPs (CtSDP1-3) restored sporulation defects in TlSDP deletion strains (ΔTlSDP), and their translated proteins, which were localized onto the cytomembrane, possessed OPT activity. Interestingly, CtSDP2 accumulated at the top of the hyphae played a distinct role in determining the sexual cycle, glutathione transport, and lifespan shortening. A unique 72nt-insertion fragment (72INS) was discovered in CtSDP2. Biological analysis of the 72INS deletion and DsRED-tagged fusion strains implied the involvement of 72INS in fungal growth and development. In contrast to TlSDP, which only contributes to conidial production, the three CtSDPs play important roles in sexual and asexual reproduction, and CtSDP2 harbors a unique functional 72INS that initiates sexual morphogenesis.

[Protective effects of artesunate combination on experimental cerebral malaria and nerve injury]

Cerebral malaria (CM) is the leading cause of death in children under 5 years in Africa, severe neurological sequelae may occur in surviving children. Although artesunate has made breakthrough progress in the clinical treatment of CM, the clinical problems of high mortality and high morbidity have not yet been completely resolved. In this study, an experimental cerebral malaria (ECM) model was established by infecting C57BL/6 mice with Pb ANKA (Plasmodium berghei ANKA) to compare parasitemia level, survival rates, and rapid murine coma behavior scale scores, cerebral microvascular obstruction, haemozoin deposition in the liver, body temperature and weight to investigate the anti-cerebral malaria effect of the artesunate compound combination. The results showed that the artesunate compound combination could improve the survival rate of Pb ANKA-infected mice, reduce the level of parasitemia, effectively improve the symptoms of ECM neurological injury, reduce cerebrovascular obstruction and haemozoin deposition in the liver, and also significantly improve body temperature, weight and other basic indicators. The results showed that the artesunate compound combination improved the pathological changes and neurological damage caused by CM. It is expected to provide a theoretical basis for human cerebral malaria patients in clinical adjuvant therapy.

Comparative analysis of tracheal intubation anesthesia vs non-tracheal intubation anesthesia for endoscopic treatment of esophago-gastric varices

BACKGROUND

Esophageal-gastro varices (EGV) is one of the common complications of cirrhosis, and esophageal gastric variceal bleeding (EGVB), characterized by acute onset and high severity, is one of the main causes of death in patients with cirrhosis. Painless endoscopic treatment is an important measure for the management of EGV rupture. At present, there are two ways of anesthesia: endotracheal intubation and non-tracheal intubation anesthesia.

AIM

To compare the safety and economy of endotracheal intubation and non-tracheal intubation anesthesia for endoscopic treatment of EGV.

METHODS

The study was performed in 58 patients with inactive bleeding who underwent endoscopic treatment for EGV from September 2017 to August 2018. They were randomly divided into an intravenous anesthesia group (non-intubation group) and a tracheal intubation anesthesia plus intravenous anesthesia group (intubation group). They were compared and analyzed in terms of basic conditions, safety, and economy. Measurement data were analyzed by the t test or rank sum test, and count data were analyzed by the chi-square test.

RESULTS

SpO₂ was significantly lower in the non-intubation group compared with the intubation group (P < 0.05), and there were no significant differences in blood pressure, heart rate, or other vital signs between the two groups (P > 0.05). The intraoperative incidence of adverse reactions such as nausea, cough, hiccup, and snoring was significantly higher in the non-intubation group than in the intubation group, but these had little effect on the operation. The induction time, recovery time, and total operative time of the non-intubation group were significantly shorter than those of the intubation group (P < 0.01). There was no significant difference in endoscopic treatment time, endoscopic treatment cost, total hospitalization cost, or hospitalization days between the two groups (P > 0.05), but the anesthesia cost was higher in the intubation group than in the non-intubation group (P < 0.01).

CONCLUSION

For patients with inactive bleeding undergoing endoscopic treatment for EGV, both tracheal intubation and non-tracheal intubation anesthesia can provide good anesthetic effects, and non-tracheal intubation anesthesia has shorter induction time, quicker recovery and lower anesthesia cost, representing a safe and economical anesthesia method.

[Effect of occupational stress on recurrent spontaneous abortion in women of childbearing age]

Objective: To investigate the influence of occupational stress on recurrent spontaneous abortion (RSA) in women of childbearing age. Methods: From January to December, 2017, 75 working women of childbearing age (25-35 years) who were admitted to a provisional hospital in Lanzhou, China and diagnosed with RSA were assigned into patient group. At a 1∶4 ratio, 300 age-matched working women who had normal first pregnancy were randomly selected as controls. A case-control study was conducted by a self-made questionnaire and the effort-reward imbalance scale. The impact of occupational stress on RSA in women of childbearing age was analyzed by evaluation of occupational harmful factors, regularity, effort-reward ratio, and sleep quality. Results: There were significant differences in the distribution of sleep, daily exercise, night shift, extrinsic-effort/low-reward score, and effort/low-reward score between the patient group and the control group (χ(2)=7.867, P<0.05; χ(2)=7.377, P<0.05; χ(2)=3.714, P<0.05; χ(2)=6.651, P<0.05; χ(2)=8.556, P<0.05) . With controlled factors such as general conditions and living habits, logistic regression analysis showed that poor sleep quality and high-effort/low-reward were risk factors for RSA (odds ratio[OR]=1.462, 95% confidence interval[CI]: 1.032~2.073; OR=3.253, 95%CI: 1.169~9.053) . A regular work was a protective factor against RSA (OR=0.644, 95%CI: 0.438-0.946) . Conclusion: In occupational stress, irregular working hours, lack of sleep, and high-effort/low-reward are risk factors for RSA. Working women of childbearing age should ensure adequate sleep, pay attention to effort-reward balance, and make a regular work schedule.

Effects of different levels of soluble PD-L1 protein on the growth of Lewis lung cancer transplanted tumor

To investigate the effects of different doses of soluble PD-L1 (soluble form of Programmed death ligand 1, sPD-L1) protein on Lewis lung cancer cells, flow cytometry was used to detect the expression of PD-L1 (Programmed death ligand 1) on the surface of Lewis lung cancer cell lines and the expression of PD-1 on the surface of T lymphocytes in peripheral blood and spleen cells of C57BL/6 mice. A Lewis lung cancer animal model of C57BL/6 mice was established by transplanting Lewis lung cancer cells subcutaneously. The sPD-L1 protein was injected into the abdominal cavity of the mouse (sPD-L1 Ig) (working dose: 2.5, 5, 10 μg per mouse), while the sPD-L1 control protein was injected as a control. The growth of Lewis lung cancer xenografts was observed. On the 18th day after tumor cell inoculation, T lymphocyte subsets in mouse spleen were determined by flow cytometry. The PD-1 molecules on the surface of Lewis lung cancer cell line, C57BL/6 mouse spleen T lymphocytes and peripheral blood T lymphocytes were positively expressed. Compared with the control group, the volume of the transplanted tumor of Lewis lung cancer in C57BL/6 mice was larger with 10 μg sPD-L1 I g injection (P less than 0.05), and no significant difference was observed in tumor volume with 2.5 μg and 5 μg injection (P > 0.05). A certain level of soluble PD-L1 (10 μg/ mouse) could promote the growth of transplanted tumors of Lewis lung cancer in C57BL/6 mice.

[Effect of dihydroartemisinin on permeability of human erythrocyte membrane infected plasmodium]

In view of the fact that the antimalarial effects of artemisinins are significant but the mechanism has not yet been clarified and there are many different opinions, it is possible that artemisinins can produce high anti-malarial efficacy through various mechanisms and multiple pathways. In addition, the researches on the pathogenesis of malaria "erythrocyte membrane plasmodial surface anion channel (PSAC)" in the past few years have provided more positive findings, which may confirm and discover the new antimalarial mechanism of artemisinins. This paper was as to study the effect of dihydroartemisinin (DHA) in vitro on erythrocyte membrane permeability of HB3 plasmodium infection, with using the mechanism of 5% sorbitol can be used to kill the Plasmodium falciparum in red blood cell membrane selectively, the effectual difference of sorbitol on the killing of P. falciparum with adding DHA or not was detected, so as to investigate whether DHA can affect the permeability of the erythrocyte membrane. Result showed that, Pre-stimulation with 10 nmol·L⁻¹ DHA (the final concentration of plasmodium in vitro culture system) for 30 min could significantly decrease the killing effect of sorbitol on the HB3 plasmodium in the P. falciparum erythrocytic cycle, and DHA may inhibit the permeability of the erythrocyte membrane for preventing sorbitol through the red blood cell membrane, thereby reducing the killing effect of sorbitol on the P. falciparum.

[Effect of dihydroartemisinin at low concentration on intervention of Plasmodium falciparum 3D7 strain]

Malaria is still the most severe strain of the human malaria parasites, and malaria disease is life-threatening which can result in severe anemia and cerebral malaria, especially in children in tropical Africa. Previous studies have shown that artemisinin and its derivatives could selectively kill erythrocytic stage of malaria and have a greater impact on the ring period. In recent years, there have been new findings of its mechanism continually. However, the concentration of artemisinin and its derivatives used in these studies can reach 50 to 80 times the half-inhibitory concentration in vitro. In this study, the international standard strain 3D7 of Plasmodium falciparum was used to culture in vitro. After half-inhibitory concentration of dihydroartemisinin was treated, the morphological changes of P. falciparum intraerythrocytic stage were observed, and then the 3D7 life cycle and effects of different developmental stages after dosing was explored. The 3D7 strain of P. falciparum was continuously synchronised more than 3 times. And dihydroartemisinin (DHA) at half maximal inhibitory concentration (10 nmol·L⁻¹) was administered for 6 hours after the last synchronization, and 3 life cycles were continuously observed (132 h). The results showed that compared with the parasites untreated by DHA, there was a noticeable delay in the life cycle of at least 36 h, indicating that the growth of 3D7 was significantly inhibited by DHA (P<0.001), and the rate of ring formation was significantly reduced (P<0.05). The trophozoites were abnormal in shape, such as shrink in size, and the number of merozoites in schizonts was significantly decreased (P<0.05). These results suggested that non-killing concentrations of DHA (meaning parasites can be inhibited but not killed) can significantly inhibit the growth of P. falciparum, which may not only affect the ring stage, but also have an impact on other stages of the P. falciparum.

ANXC7 Is a Mitochondrion-Localized Annexin Involved in Controlling Conidium Development and Oxidative Resistance in the Thermophilic Fungus Thermomyces lanuginosus

Annexins (ANXs) are widely expressed and structurally related proteins which play multiple biological roles in animals, plants, and fungi. Although ANXs have been localized to the cytosol and the cell membrane and the molecular basis of the four annexin repeats is well established, the in vivo roles of these proteins are still far from clear, particularly with regard to the filamentous fungi. Thermomyces lanuginosus, a thermophilic fungus, is widely used in the fermentation industry; however, the role of ANX in this organism is unknown. In this study, a single ANX homologue (ANXC7) was identified and characterized in T. lanuginosus. The expression pattern indicated that ANXC7 is closely associated to conidium development, and it accumulated in the mitochondria of the forming conidia. The deletion of ANXC7 (ΔANXC7) resulted in no obvious phenotype related to colony growth on solid CM medium. However, when ΔANXC7 was grown in CM liquid culture, the mycelium masses appeared to be larger and looser compared to the wild-type. Additionally, the dry weight of the mutant mycelia was significantly increased. Under conditions that compromise cell-wall integrity, ΔANXC7 was less vulnerable than the wild-type with regard to such damage. Moreover, based on a surface hydrophobicity test, the ΔANXC7 strain was clearly less hydrophobic. The growth of ΔANXC7 was inhibited when grown under selected stress conditions, particularly with regard to salt stress; however, the oxidative resistance to exogenous H₂O₂ in ΔANXC7 was increased, and endogenous H₂O₂ levels within the ΔANXC7 were lower than in the wild-type, thereby suggesting that the ANXC7 specifically controls oxidative resistance. Based on microscopic observation, 4-day-conidia were more prevalent than 5-day conidia on the conidiophore stalk of ΔANXC7, even though the ΔANXC7 demonstrated an increased production of conidia during these days, indicating precocious conidial maturation and shedding from the conidiophore stalk in this strain. Taken together, our data indicate that ANXC7 localizes to the mitochondria and is involved in controlling conidium development and oxidative resistance in T. lanuginosus.

Promoting Ethylene Selectivity from CO2 Electroreduction on CuO Supported onto CO2 Capture Materials

Cu is a unique catalyst for CO₂ electroreduction, since it can catalyze CO₂ reduction to a series of hydrocarbons, alcohols, and carboxylic acids. Nevertheless, such Cu catalysts suffer from poor selectivity. High pressure of CO₂ is considered to facilitate the activity and selectivity of CO₂ reduction. Herein, a new strategy is presented for CO₂ reduction with improved C₂ H₄ selectivity on a Cu catalyst by using CO₂ capture materials as the support at ambient pressure. N-doped carbon (N_x C) was synthesized through high-temperature carbonization of melamine and l-lysine. We observed that the CO₂ uptake capacity of N_x C depends on both the microporous area and the content of pyridinic N species, which can be controlled by the carbonization temperature (600-800 °C). The as-prepared CuO/N_x C catalysts exhibit a considerably higher C₂ H₄ faradaic efficiency (36 %) than CuO supported on XC-72 carbon black (19 %), or unsupported CuO (20 %). Moreover, there is a good linear relationship between the C₂ H₄ faradaic efficiency and CO₂ uptake capacity of the supports for CuO. The local high CO₂ concentration near Cu catalysts, created by CO₂ capture materials, was proposed to increase the coverage of CO intermediate, which is favorable for the coupling of two CO units in the formation of C₂ H₄ . This study demonstrates that pairing Cu catalysts with CO₂ capture supports is a promising approach for designing highly effective CO₂ reduction electrocatalysts.

[Efficient discovery and capturing of nNOS-PSD-95 uncouplers from Trifolium pratense]

Magnetic molecularly imprinted polymers(MMIPs) were prepared with ZL006 as template, acrylamide(AA) as the functional monomer, and acetonitrile as pore-forming agent; then Fourier transform infrared spectroscopy(FT-IR) and scanning electron microscopy(SEM) were used to characterize their forms and structures. Simultaneously, the MMIPs prepared previously were used as sorbents for dispersive magnetic solid phase extraction(DSPE) to capture and identify potential nNOS-PSD-95 uncouplers from extracts of Trifolium pratense and the the activities of the screened compounds were evaluated by the neuroprotective effect and co-immunoprecipitation test. The experiment revealed that the successfully synthesized MMIPs showed good dispersiveness, suitable particle size and good adsorption properties. Formononetin, prunetin and biochanin A were separated and enriched from Trifolium pratense by using the MMIPs as artificial antibodies and finally biochanin A was found to have higher cytoprotective action and uncoupling action according to the neuroprotective effect and co-immunoprecipitation test.

[Current advance in cerebral malaria]

Cerebral malaria (CM), a severe neurological syndrome caused by Plasmodium falciparum infection, is a serious life-threatening disease with a high mortality. Survivors' persistent brain injury is manifested as long-term neurocognitive disorders. The main neuropathological feature of CM is the sequestration of parasited red blood cells (pRBCs) in cerebral microvessels. Other neuropathological features of CM include petechial hemorrhage in the brain parenchyma, annular hemorrhage, extensive brain endothelial cell activation, and focal endothelial cell injury and necrosis. However, its pathogenesis is still not clear. Currently, some studies have suggested that the pathogenesis of cerebral malaria mainly include pRBC adhesion, inflammatory reaction cascade, vascular leakage damage and brain hypoxia. Studies have shown that the biomarkers currently used as diagnostic and prognostic markers for CM include C-X-C motif chemokine ligand 10 (CXCL10), CXC chemokine ligand 4 (CXCL4), angiopoietin (Ang). In this paper, we systematically summarize the basic and clinical research for cerebral malaria in recent years and the latest literatures for drug studies, and focused on the advance of studies on cerebral malaria and its immunologic mechanism in the recent three years in the aspects of cytokines, immune cells, regulatory factors and biomarkers, so as to provide references for relevant studies.

Long-term administration of pyridostigmine attenuates pressure overload-induced cardiac hypertrophy by inhibiting calcineurin signalling

Cardiac hypertrophy is associated with autonomic imbalance, characterized by enhanced sympathetic activity and withdrawal of parasympathetic control. Increased parasympathetic function improves ventricular performance. However, whether pyridostigmine, a reversible acetylcholinesterase inhibitor, can offset cardiac hypertrophy induced by pressure overload remains unclear. Hence, this study aimed to determine whether pyridostigmine can ameliorate pressure overload‐induced cardiac hypertrophy and identify the underlying mechanisms. Rats were subjected to either sham or constriction of abdominal aorta surgery and treated with or without pyridostigmine for 8 weeks. Vagal activity and cardiac function were determined using PowerLab. Cardiac hypertrophy was evaluated using various histological stains. Protein markers for cardiac hypertrophy were quantitated by Western blot and immunoprecipitation. Pressure overload resulted in a marked reduction in vagal discharge and a profound increase in cardiac hypertrophy index and cardiac dysfunction. Pyridostigmine increased the acetylcholine levels by inhibiting acetylcholinesterase in rats with pressure overload. Pyridostigmine significantly attenuated cardiac hypertrophy based on reduction in left ventricular weight/body weight, suppression of the levels of atrial natriuretic peptide, brain natriuretic peptide and β‐myosin heavy chain, and a reduction in cardiac fibrosis. These effects were accompanied by marked improvement of cardiac function. Additionally, pyridostigmine inhibited the CaN/NFAT3/GATA4 pathway and suppressed Orai1/STIM1 complex formation. In conclusion, pressure overload resulted in cardiac hypertrophy, cardiac dysfunction and a significant reduction in vagal discharge. Pyridostigmine attenuated cardiac hypertrophy and improved cardiac function, which was related to improved cholinergic transmission efficiency (decreased acetylcholinesterase and increased acetylcholine), inhibition of the CaN/NFAT3/GATA4 pathway and suppression of the interaction of Orai1/STIM1.

Comparative proteomics analyses for 139A and ME7 scrapie infected mice brains in the middle and terminal stages

PURPOSE

To analyze the proteomics patterns in the cortex regions of scrapie strains 139A- and ME7-infected mice collected in the middle and terminal stages.

EXPERIMENTAL DESIGN

Western Blot and immunohistochemistry methods are used to analyze the pathological changes in mice collected in the middle and terminal stages. The technique of iTRAQ and multidimensional LC and MS are used to analyze the proteomics patterns of mice in different stages.

RESULTS

In total, 2891 with 95% confidence interval are identified. The study here also demonstrates a similar protein expressions in the CNS tissues of two scrapie strains infected mice at the terminal stages, but markedly different one between the middle and terminal samples, not only in the numbers of differentially expressed proteins and involved gene ontologies and pathways but also in the relevant functional constitutions.

CONCLUSIONS

It may provide useful clue in exploring the abnormalities of biological functions at different time points of prion infections and in searching for potential therapeutic and diagnostic biomarkers for prion diseases.

Management of duodenal injury: Report of a fatal case and literature review

Duodenal injury accounts for 3%-5% of all cases of closed abdominal trauma. Because of the special location of the duodenum in the human body, duodenal injury is often caused by a relatively large trauma. As a consequence, management of duodenal injury is more difficult, and it is often associated with more complications and high mortality. Here we report a fatal case of duodenal injury after surgery. We also performed a literature review to discuss the management of duodenal injury. Surgery should be chosen reasonably, and comprehensive medical treatment should be emphasized.

Down-regulation of brain-derived neurotrophic factor and its signaling components in the brain tissues of scrapie experimental animals

Prion is a unique nucleic acid-free pathogen that causes human and animal fatal neurodegenerative diseases. Brain-derived neurotrophic factor (BDNF) is a prototypic neurotrophin that helps to support the survival of existing neurons, and encourage the growth and differentiation of new neurons and synapses through axonal and dendritic sprouting. There are two distinct classes of glycosylated receptors, neurotrophin receptor p75 (p75NTR) and tropomyosin-related kinase (Trk), that can bind to BDNF. To obtain insights into the possible alterations of brain BDNF and its signaling pathway in prion disease, the levels of BDNF and several molecules in the BDNF pathway in the brain tissues of scrapie agents 263K-infected hamsters were separately evaluated. Western blots and/or immunohistochemical (IHC) assays revealed that BDNF, TrkB, GRB2 and p75NTR, were significantly downregulated in the brain tissues of scrapie-infected rodents at terminal stage. Double-stained immunofluorescent assay (IFA) demonstrated that BDNF and phospho-TrkB predominately expressed in neurons. Dynamic analyses of the brain samples collected at the different time-points during the incubation period illustrated continuous decreases of BDNF, TrkB, phospho-TrkB, GRB2 and p75NTR, which correlated well with neuron loss. However, these proteins remained almost unchanged in the prion infected cell line SMB-S15 compared with those of its normal cell line SMB-PS. These data suggest that the BDNF signaling pathway is severely hindered in the brains of prion disease, which may contribute, at least partially, to the neuron death.

High remission and low relapse with prolonged intensive DMARD therapy in rheumatoid arthritis (PRINT): A multicenter randomized clinical trial

OBJECTIVES

To determine whether prolonged intensive disease-modifying antirheumatic drug (DMARD) treatment (PRINT) leads to high remission and low relapse rates in patients with severe rheumatoid arthritis (RA).

METHODS

In this multicenter, randomized and parallel treatment trial, 346 patients with active RA (disease activity score (28 joints) [DAS28] (erythrocyte sedimentation rate [ESR]) > 5.1) were enrolled from 9 centers. In phase 1, patients received intensive treatment with methotrexate, leflunomide, and hydroxychloroquine, up to 36 weeks, until remission (DAS28 ≤ 2.6) or a low disease activity (2.6 < DAS28 ≤ 3.2) was achieved. In phase 2, patients achieving remission or low disease activity were followed up with randomization to 1 of 2 step-down protocols: leflunomide plus hydroxychloroquine combination or leflunomide monotherapy. The primary endpoints were good European League Against Rheumatism (EULAR) response (DAS28 (ESR) < 3.2 and a decrease of DAS28 by at least 1.2) during the intensive treatment and the disease state retention rate during step-down maintenance treatment. Predictors of a good EULAR response in the intensive treatment period and disease flare in the maintenance period were sought.

RESULTS

A good EULAR response was achieved in 18.7%, 36.9%, and 54.1% of patients at 12, 24, and 36 weeks, respectively. By 36 weeks, 75.4% of patients achieved good and moderate EULAR responses. Compared with those achieving low disease activity and a high health assessment questionnaire (HAQ > 0.5), patients achieving remission (DAS28 ≤ 2.6) and low HAQ (≤ 0.5) had a significantly higher retention rate when tapering the DMARDs treatment (P = 0.046 and P = 0.01, respectively). There was no advantage on tapering to combination rather than monotherapy.

CONCLUSIONS

Remission was achieved in a proportion of patients with RA receiving prolonged intensive DMARD therapy. Low disease activity at the start of disease taper leads to less subsequent flares. Leflunomide is a good maintenance treatment as single treatment.

Overexpression of PLK3 Mediates the Degradation of Abnormal Prion Proteins Dependent on Chaperone-Mediated Autophagy

Polo-like kinase 3 (PLK3) is the main cause of cell cycle reentry-related neuronal apoptosis which has been implicated in the pathogenesis of prion diseases. Previous work also showed the regulatory activity of exogenous PLK3 on the degradation of PrP (prion protein) mutants and pathogenic PrP^Sc; however, the precise mechanisms remain unknown. In this study, we identified that the overexpression of PLK3-mediated degradation of PrP mutant and PrP^Sc was repressed by lysosome rather than by proteasomal and macroautophagy inhibitors. Core components of chaperone-mediated autophagy (CMA) effectors, lysosome-associated membrane protein type 2A (LAMP2a), and heat shock cognate protein 70 (Hsc70) are markedly decreased in the HEK293T cells expressing PrP mutant and scrapie-infected cell line SMB-S15. Meanwhile, PrP mutant showed ability to interact with LAMP2a and Hsc70. Overexpression of PLK3 sufficiently increased the cellular levels of LAMP2a and Hsc70, accompanying with declining the accumulations of PrP mutant and PrP^Sc. The kinase domain (KD) of PLK3 was responsible for elevating LAMP2a and Hsc70. Knockdown of endogenous PLK3 enhanced the activity of macroautophagy in the cultured cells. Moreover, time-dependent reductions of LAMP2a and Hsc70 were also observed in the brain tissues of hamster-adapted scrapie agent 263K-infected hamsters, indicating an impairment of CMA during prion infection. Those data indicate that the overexpression of PLK3-mediated degradation of abnormal PrP is largely dependent on CMA pathway.

Analysis of the advantage features of Beijing surveillance network for Creutzfeldt-Jakob disease

Since 2006, China has conducted the surveillance program for Creutzfeldt-Jakob disease (CJD) and other subtypes of prion diseases covering 12 provinces. In this study, the characteristics and special role of Beijing CJD surveillance network in the national CJD surveillance system were analyzed. Based on the registered permanent resident places, all reporting suspected CJD cases and diagnosed CJD cases via Beijing CJD surveillance network between 2006 and 2013 were grouped as the cases from Beijing and from outside of Beijing. Both numbers of the suspected and diagnosed CJD cases via Beijing CJD surveillance network constantly increased along with the years, totally 532 reporting cases and 192 diagnosed CJD cases were obtained in the past 8 y. About 75% of suspected and diagnosed CJD cases via Beijing CJD surveillance network came from other provinces, mainly from neighboring provinces. Altogether, 46 different hospitals in the Beijing region have reported suspected CJD cases to the CJD surveillance system during the period from 2006 to 2013. Five hospitals continually reported suspected CJD cases during those 8 y and 5 other hospitals had reported cases except for 1 to 2 y. Additionally, we found that the diagnosed CJD patients from Beijing region had less numbers of hospital transfer and shorter interval from the disease onset to the final diagnosis than those outside of Beijing. It indicates that as the most important component, Beijing CJD surveillance network functions more actively, which supplies the special medical services not only for Beijing residents but also for patients from all of China.

The Brain NO Levels and NOS Activities Ascended in the Early and Middle Stages and Descended in the Terminal Stage in Scrapie-Infected Animal Models

The infections of prion agents may cause progressive and fatal neurodegenerative diseases in humans and a serial of animal species. Previous studies have proposed that the levels of nitric oxide (NO) and nitric oxide synthase (NOS) in the brains of some neurodegeneration diseases changed, while S-nitrosylation (SNO) of many brain proteins altered in prion diseases. To elucidate the potential changes of brain NO levels during prion infection, the NO levels and NOS activities in the brain tissues of three scrapie experimental rodents were measured, including scrapie agent 263 K-infected hamsters and 139A- and ME7-infected mice. Both NO levels and NOS activities, including total NOS (TNOS) and inducible NOS (iNOS), were increased at the terminal stages of scrapie-infected animals. Assays of the brain samples collected at different time points during scrapie infection showed that the NO levels and NOS activities started to increase at early stage, reached to the peak in the middle stage, and dropped down at late stage. Western blots for brain iNOS revealed increased firstly and decreased late, especially in the brains of 139A- and ME7-infected mice. In line with those alterations, the levels of the SNO forms of several selected brain proteins such as aquaporin-1 (AQP1), calcium/calmodulin-dependent protein kinase II (CaMKII), neurogranin, and opalin, underwent similar changing trends, while their total protein levels did not change obviously during scrapie infection. Our data here for the first time illustrate the changing profile of brain NO and NOS during prion infection. Time-dependent alterations of brain NO level and the associated protein S-nitrosylation process may contribute greatly to the neuropathological damage in prion diseases.

Re-infection of the prion from the scrapie‑infected cell line SMB-S15 in three strains of mice, CD1, C57BL/6 and Balb/c

It is well known that the SMB-S15 cell line was originally established by cultures from the brains of mice affected by the Chandler scrapie strain, and this cell line may express PrP^Sc permanently. However, the infectivity of the S15-derived prions on experimental animals has not yet been well documented. In the present study, the cell lysates of SMB-S15 were intracerebrally inoculated into three different strains of mice, namely C57BL/6, Balb/c and CD1. Prion protein (PRNP) gene sequencing revealed the same encoded PrP proteins in the sequences of amino acids in the three strains of mice, in addition to a synonymous single nucleotide polymorphism (SNP) in CD1 mice. All infected mice developed typical experimental transmissible spongiform encephalopathies (TSEs) approximately six months post-infection. The clinical features of three infected mice were comparable. The pathogenic characteristics, such as the electrophoretic and glycosylation profiles and proteinase K (PK) resistance of PrP^Sc molecules, as well as the neuropathological characteristics, such as spongiform vacuolation, PrP^Sc deposits in cortex regions, astrogliosis and activated microglia, were also similar in all three strains of infected mice. However, PrP^Sc deposits in the cerebellums of CD1 mice were significantly fewer, which was linked with the observation that lower numbers of CD1 mice presented cerebellum-associated symptoms. Successive inoculation of the individual strains of mice with brain homogenates from the infected mice also induced typical experimental scrapie. The data in the present study thus confirm that the prion agent in SMB-S15 cells causes stable infectivity in different types of mice with distinct phenotypes after long-term propagation in vitro. The present study also provides further scrapie rodent models, which may be used in further studies.