Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Objective: To analyze the clinical epidemiological characteristics including composition of pathogens , clinical characteristics, and disease prognosis acute bacterial meningitis (ABM) in Chinese children. Methods: A retrospective analysis was performed on the clinical and laboratory data of 1 610 children <15 years of age with ABM in 33 tertiary hospitals in China from January 2019 to December 2020. Patients were divided into different groups according to age,<28 days group, 28 days to <3 months group, 3 months to <1 year group, 1-<5 years of age group, 5-<15 years of age group; etiology confirmed group and clinically diagnosed group according to etiology diagnosis. Non-numeric variables were analyzed with the Chi-square test or Fisher's exact test, while non-normal distrituction numeric variables were compared with nonparametric test. Results: Among 1 610 children with ABM, 955 were male and 650 were female (5 cases were not provided with gender information), and the age of onset was 1.5 (0.5, 5.5) months. There were 588 cases age from <28 days, 462 cases age from 28 days to <3 months, 302 cases age from 3 months to <1 year of age group, 156 cases in the 1-<5 years of age and 101 cases in the 5-<15 years of age. The detection rates were 38.8% (95/245) and 31.5% (70/222) of Escherichia coli and 27.8% (68/245) and 35.1% (78/222) of Streptococcus agalactiae in infants younger than 28 days of age and 28 days to 3 months of age; the detection rates of Streptococcus pneumonia, Escherichia coli, and Streptococcus agalactiae were 34.3% (61/178), 14.0% (25/178) and 13.5% (24/178) in the 3 months of age to <1 year of age group; the dominant pathogens were Streptococcus pneumoniae and the detection rate were 67.9% (74/109) and 44.4% (16/36) in the 1-<5 years of age and 5-<15 years of age . There were 9.7% (19/195) strains of Escherichia coli producing ultra-broad-spectrum β-lactamases. The positive rates of cerebrospinal fluid (CSF) culture and blood culture were 32.2% (515/1 598) and 25.0% (400/1 598), while 38.2% (126/330)and 25.3% (21/83) in CSF metagenomics next generation sequencing and Streptococcus pneumoniae antigen detection. There were 4.3% (32/790) cases of which CSF white blood cell counts were normal in etiology confirmed group. Among 1 610 children with ABM, main intracranial imaging complications were subdural effusion and (or) empyema in 349 cases (21.7%), hydrocephalus in 233 cases (14.5%), brain abscess in 178 cases (11.1%), and other cerebrovascular diseases, including encephalomalacia, cerebral infarction, and encephalatrophy, in 174 cases (10.8%). Among the 166 cases (10.3%) with unfavorable outcome, 32 cases (2.0%) died among whom 24 cases died before 1 year of age, and 37 cases (2.3%) had recurrence among whom 25 cases had recurrence within 3 weeks. The incidences of subdural effusion and (or) empyema, brain abscess and ependymitis in the etiology confirmed group were significantly higher than those in the clinically diagnosed group (26.2% (207/790) vs. 17.3% (142/820), 13.0% (103/790) vs. 9.1% (75/820), 4.6% (36/790) vs. 2.7% (22/820), χ²=18.71, 6.20, 4.07, all P<0.05), but there was no significant difference in the unfavorable outcomes, mortility, and recurrence between these 2 groups (all P>0.05). Conclusions: The onset age of ABM in children is usually within 1 year of age, especially <3 months. The common pathogens in infants <3 months of age are Escherichia coli and Streptococcus agalactiae, and the dominant pathogen in infant ≥3 months is Streptococcus pneumoniae. Subdural effusion and (or) empyema and hydrocephalus are common complications. ABM should not be excluded even if CSF white blood cell counts is within normal range. Standardized bacteriological examination should be paid more attention to increase the pathogenic detection rate. Non-culture CSF detection methods may facilitate the pathogenic diagnosis.
Adolescent ; Brain Abscess ; Child ; Child, Preschool ; Escherichia coli ; Female ; Humans ; Hydrocephalus ; Infant ; Infant, Newborn ; Male ; Meningitis, Bacterial/epidemiology* ; Retrospective Studies ; Streptococcus agalactiae ; Streptococcus pneumoniae ; Subdural Effusion ; beta-Lactamases

LIN28 is an RNA binding protein with important roles in early embryo development, stem cell differentiation/reprogramming, tumorigenesis and metabolism. Previous studies have focused mainly on its role in the cytosol where it interacts with Let-7 microRNA precursors or mRNAs, and few have addressed LIN28's role within the nucleus. Here, we show that LIN28 displays dynamic temporal and spatial expression during murine embryo development. Maternal LIN28 expression drops upon exit from the 2-cell stage, and zygotic LIN28 protein is induced at the forming nucleolus during 4-cell to blastocyst stage development, to become dominantly expressed in the cytosol after implantation. In cultured pluripotent stem cells (PSCs), loss of LIN28 led to nucleolar stress and activation of a 2-cell/4-cell-like transcriptional program characterized by the expression of endogenous retrovirus genes. Mechanistically, LIN28 binds to small nucleolar RNAs and rRNA to maintain nucleolar integrity, and its loss leads to nucleolar phase separation defects, ribosomal stress and activation of P53 which in turn binds to and activates 2C transcription factor Dux. LIN28 also resides in a complex containing the nucleolar factor Nucleolin (NCL) and the transcriptional repressor TRIM28, and LIN28 loss leads to reduced occupancy of the NCL/TRIM28 complex on the Dux and rDNA loci, and thus de-repressed Dux and reduced rRNA expression. Lin28 knockout cells with nucleolar stress are more likely to assume a slowly cycling, translationally inert and anabolically inactive state, which is a part of previously unappreciated 2C-like transcriptional program. These findings elucidate novel roles for nucleolar LIN28 in PSCs, and a new mechanism linking 2C program and nucleolar functions in PSCs and early embryo development.
Animals ; Cell Differentiation ; Embryo, Mammalian/metabolism* ; Embryonic Development ; Mice ; Pluripotent Stem Cells/metabolism* ; RNA, Messenger/genetics* ; RNA, Ribosomal ; RNA-Binding Proteins/metabolism* ; Transcription Factors/metabolism* ; Zygote/metabolism*

Molecular pharmacognosy is a science of classification and identification, cultivation and protection, and production of active ingredients of graduated drugs at the molecular level. The proposal of molecular pharmacognosy allows the research of crude drugs to advance from the microscopic level to the genetic level. Pueraria lobata root, as a medicinal and edible plant, has high application value and economic value. There are many varieties that are easy to cause confusion, and it is not easy to distinguish and identify according to traditional identification methods. Moreover, the research of P. lobate root at the genetic level is still relatively shallow. the study received extensive attention of scholars. This article reviews recent research on molecular identification of P. lobate, transcriptome sequencing, cloning and synthesis of functional genes of P. lobate root in recent years in order to provide references for further promoting the development and utilization of P. lobate root and its active ingredients.
Pharmacognosy ; Plant Roots/genetics* ; Pueraria

Gene expression labeling and conditional manipulation of gene function are important for elaborate dissection of gene function. However, contemporary generation of pairwise dual-function knockin alleles to achieve both conditional and geno-tagging effects with a single donor has not been reported. Here we first developed a strategy based on a flipping donor named FoRe to generate conditional knockout alleles coupled with fluorescent allele-labeling through NHEJ-mediated unidirectional targeted insertion in zebrafish facilitated by the CRISPR/Cas system. We demonstrated the feasibility of this strategy at sox10 and isl1 loci, and successfully achieved Cre-induced conditional knockout of target gene function and simultaneous switch of the fluorescent reporter, allowing generation of genetic mosaics for lineage tracing. We then improved the donor design enabling efficient one-step bidirectional knockin to generate paired positive and negative conditional alleles, both tagged with two different fluorescent reporters. By introducing Cre recombinase, these alleles could be used to achieve both conditional knockout and conditional gene restoration in parallel; furthermore, differential fluorescent labeling of the positive and negative alleles enables simple, early and efficient real-time discrimination of individual live embryos bearing different genotypes prior to the emergence of morphologically visible phenotypes. We named our improved donor as Bi-FoRe and demonstrated its feasibility at the sox10 locus. Furthermore, we eliminated the undesirable bacterial backbone in the donor using minicircle DNA technology. Our system could easily be expanded for other applications or to other organisms, and coupling fluorescent labeling of gene expression and conditional manipulation of gene function will provide unique opportunities to fully reveal the power of emerging single-cell sequencing technologies.
Alleles ; Animals ; CRISPR-Cas Systems ; DNA End-Joining Repair ; DNA, Circular/metabolism* ; Embryo, Nonmammalian ; Gene Editing/methods* ; Gene Knock-In Techniques ; Gene Knockout Techniques ; Genes, Reporter ; Genetic Loci ; Genotyping Techniques ; Green Fluorescent Proteins/metabolism* ; Integrases/metabolism* ; Luminescent Proteins/metabolism* ; Mutagenesis, Insertional ; Single-Cell Analysis ; Zebrafish/metabolism*

Objective:To compare the chemical constituents of Puerariae Flos from three different varieties of Pueraria montana var. lobata， P. montana var. thomsonii and P. montana var. montana. Method:Ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry （UPLC-Q-TOF-MS） was used with the mobile phase of 0.1% formic acid aqueous solution （A）-acetonitrile （B） for gradient elution （0-20 min， 10%-30%B； 20-30 min， 30%-55%B； 30-35 min， 55%-95%B； 35-37 min， 95%B； 37-40 min， 95%-10%B）， the flow rate was 0.25 mL·min^-1. Electrospray ionization （ESI） was used to scan and collect MS data in positive and negative ion modes with scanning range of m/z 50-1 500. The chemical components from different sources of Puerariae Flos were identified in combination with the chemical composition database and literature information. After the obtained data were normalized by MarkerView^TM 1.2.1， they were imported into SICMA-P 14.1 software for principal component analysis （PCA） and orthogonal partial least squares discriminant analysis （OPLS-DA） to select the main differentiated components among the three different varieties. Result:A total of 35 compounds were identified from three different varieties of Puerariae Flos， including 22 isoflavones， 6 flavonoids and 7 saponins. The flowers of P. lobata， P. montana var. thomsonii and P. montana var. montana contained 32， 35， 33 compounds， respectively. And 18 differential compounds were screened under the positive and negative ion modes， including kakkalide， tectoridin， 6″-O-xylosyl-tectoridin， 4'-methyltectorigenin-7-glucoside， glycitin， 6″-O-xylosyl-glycitin， irisolidone， kaikasaponin Ⅲ， 6″-O-malonylglycitin， kakkalidone， tectorigenin， rutin， soyasaponin BB， vitexin， biochanin A， genistin， kakkatin， azukisaponin Ⅱ. Conclusion:This research is the first to systematically study the chemical constituents of the flower of P. montana var. montana， although the flower of P. montana var. montana is used as adulterants， it has high contents of tectoridin and 6″-O-xylosyl-tectoridin， which has great potential for development. The efficacy components such as kakkalide and tectoridin in Puerariae Flos from the three sources of varieties are obviously different， and it is necessary to carefully consider the application of these three varieties as Puerariae Flos.

OBJECTIVE: To understand the differences between young male students who have sex with men (MSM) with and without human immunodeficiency virus (HIV)-infection in acquired immure deficiency syndrome (AIDS)-related knowledge and behavior, and to provide a scientific reference to make targeted and effective measures in AIDS prevention. METHODS: Using snow balling sampling combined with participants' referral, we conducted a questionnaire survey among 548 young MSM students (in whom there were both HIV-positive and HIV-negative) in Harbin, Tianjin, Xi'an, and Chongqing cities from April 2017 to March 2018. The chi-square test and binary Logistic regression were used to compare the differences in AIDS-related knowledge and behavior between males with and without HIV-infection. RESULTS: A total of 583 questionnaires were obtained, of which 548 were valid, with an effective rate of 94.0%. Having a junior college education or below (P=0.002), a monthly consumption level of less than 2 000 RMB (P=0.021), and living off campus (P=0.004) were associated with being tested positive for HIV. In any period of schooling, receiving AIDS prevention education was a protective factor for HIV infection [Primary school OR=0.203 (0.073－0.561), junior high school OR=0.287 (0.142－0.581), senior high school OR=0.271 (0.142－0.518), and university OR=0.322 (0.168－0.616)]. There was no statistical difference between HIV positive and negative young MSM students in the cognition of "AIDS-related Knowledge for Public"(P=0.907) and "AIDS-related Knowledge for Youth"(P=0.782), with the awareness rate all about 90%. There was a statistical difference in the need for some specific knowledge (For "AIDS prevention and treatment policy", P=0.012, for "Ways to identify and prevent high-risk sexual behavior", P < 0.001). HIV-positive males had a younger age of first sexual activity (P=0.006), had more sexual partners in the early (P < 0.001) and had lower frequency of condom use (P < 0.001). However, there was no statistical difference in the later number of sexual partners (P=0.247) and the frequency of condom use (For regular sex partners, P=0.735, and for casual sex partners, P=0.765), which might be related to the change of sexual behavior characteristics caused by HIV infection (For regular sex partners, P < 0.001, and for casual sex partners, P=0.006). CONCLUSION There was no statistical difference between HIV positive and negative young MSM students in the cognition of "AIDS-related Knowledge for Public" and "AIDS-related Knowledge for Youth", which were both lower than 95% required by the state. However, the specificity in the knowledge needs was certainly shown. There was no significant difference in the recent sexual behavior between the two groups, but HIV positive students were more likely to have high-risk sexual behaviors in the early stage, so we should strengthen and move forward the sex education and AIDS prevention education with adjusted contents, and prevent high-risk sexual behaviors within young MSM students in the early stage.
Adolescent ; HIV ; HIV Infections/prevention & control* ; Health Knowledge, Attitudes, Practice ; Homosexuality, Male ; Humans ; Male ; Sexual Behavior ; Sexual and Gender Minorities ; Students ; Surveys and Questionnaires

OBJECTIVE: To explore the appropriate procedures for preparing extracellular microvesicles (MV) derived from human mesenchymal stem cells (MSC). METHODS: Human MSCs from umbilical cords were cultured in a serum-free medium and maintained in a basal medium for 72 hours after the cell confluence reached to 80%. The supernatants of cultured cells were collected and MVs were enriched. MVs were identified by flow cytometry and electron microscopy. The total protein amount in MVs was used as a parameter for the content of MVs. The supernatants were adjusted to different pH values, and the output of MVs was detected. The supernatants were also collected for enriching the MV and detecting the protein content of MV after the cells were maintained in the basic medium for different time. RESULTS: Flow cytometric analysis showed that the MVs expressed CD9, CD63 and CD81, morphologically presented round under an electron microscope and the diameter of MV was around 100 nm. After enrichment of MV, the protein content of MVs in the supernatants was 416.8±128.1, 255.4±77.9 and 142.8±46.4 μg per 10 MSC，respectively at pH of supernatant 3, 7 and 9 (P＜0.05). The protein content of the supernatants per 10 MSC was 173.6±44.5, 262.4±49.6 and 364.2±37.8 μg respectively after starvation culture for 48, 72 and 96 hrs (P＜0.05). CONCLUSION MVs can be readily collected after MSCs were starved for 96 hours, and the pH of the supernatants is adjusted at 3.0.
Cell-Derived Microparticles ; Cells, Cultured ; Flow Cytometry ; Humans ; Mesenchymal Stem Cells ; Umbilical Cord

OBJECTIVES: To develop a new Chinese medicine (CM)-based drug and to evaluate its safety and effect for suppressing acute respiratory distress syndrome (ARDS) in COVID-19 patients. METHODS: A putative ARDS-suppressing drug Keguan-1 was first developed and then evaluated by a randomized, controlled two-arm trial. The two arms of the trial consist of a control therapy (alpha interferon inhalation, 50 µg twice daily; and lopinavir/ritonavir, 400 and 100 mg twice daily, respectively) and a testing therapy (control therapy plus Keguan-1 19.4 g twice daily) by random number table at 1:1 ratio with 24 cases each group. After 2-week treatment, adverse events, time to fever resolution, ARDS development, and lung injury on newly diagnosed COVID-19 patients were assessed. RESULTS: An analysis of the data from the first 30 participants showed that the control arm and the testing arm did not exhibit any significant differences in terms of adverse events. Based on this result, the study was expanded to include a total of 48 participants (24 cases each arm). The results show that compared with the control arm, the testing arm exhibited a significant improvement in time to fever resolution (P=0.035), and a significant reduction in the development of ARDS (P=0.048). CONCLUSIONS Keguan-1-based integrative therapy was safe and superior to the standard therapy in suppressing the development of ARDS in COVID-19 patients. (Trial registration No. NCT04251871 at www.clinicaltrials.gov ).
Administration, Inhalation ; Adult ; China ; Coronavirus Infections ; diagnosis ; drug therapy ; mortality ; Dose-Response Relationship, Drug ; Drug Administration Schedule ; Drugs, Chinese Herbal ; administration & dosage ; Female ; Follow-Up Studies ; Humans ; Integrative Medicine ; Interferon-alpha ; administration & dosage ; Lopinavir ; administration & dosage ; Male ; Middle Aged ; Pandemics ; Pneumonia, Viral ; diagnosis ; drug therapy ; mortality ; Risk Assessment ; Severe Acute Respiratory Syndrome ; diagnosis ; drug therapy ; mortality ; Severity of Illness Index ; Survival Rate

This study engineered β-carotene ketolase CrtW and β-carotene hydroxylase CrtZ to improve biosynthesis of astaxanthin in Escherichia coli. Firstly, crtW was randomly mutated to increase CrtW activities on conversion from β-carotene to astaxanthin. A crtW* mutant with A6T, T105A and L239M mutations has improved 5.35-fold astaxanthin production compared with the wild-type control. Secondly, the expression levels of crtW* and crtZ on chromosomal were balanced by simultaneous modulation RBS regions of their genes using RBS library. The strain RBS54 selected from RBS library, directed the pathway exclusively towards the desired product astaxanthin as predominant carotenoid (99%). Lastly, the number of chromosomal copies of the balanced crtW-crtZ cassette from RBS54 was increased using a Cre-loxP based technique, and a strain with 30 copies of the crtW*-crtZ cassette was selected. This final strain DL-A008 had a 9.8-fold increase of astaxanthin production compared with the wild-type control. Fed-batch fermentation showed that DL-A008 produced astaxanthin as predominant carotenoid (99%) with a specific titer of 0.88 g·L without addition of inducer. In conclusion, through constructing crtW mutation, balancing the expression levels between crtW* and crtZ, and increasing the copy number of the balanced crtW*-crtZ cassette, the activities of β-carotene ketolase and β-carotene hydroxylase were improved for conversion of β-carotene to astaxanthin with higher efficiency. The series of conventional and novel metabolic engineering strategies were designed and applied to construct the astaxanthin hetero-producer strain of E. coli, possibly offering a general approach for the construction of stable hetero-producer strains for other natural products.