bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of erythromycin-resistant Streptococcus pneumoniae isolates causing invasive diseases in Chinese children
Authors: MA Xiang , YAO Kai-hu , XIE Gui-lin , ZHENG YUE-jie , WANG Chuan-qing , SHANG Yun-xiao , WANG Hui-yun , WAN Li-ya , LIU Lan , LI Chang-chong , JI Wei , XU Xi-wei , WANG Ya-ting , XU Pei-ru , YU Sang-jie , YANG Yong-hong 
Published: January 2024

Background
Erythromycin-resistant Streptococcus pneumoniae isolates that causing invasive pneumococcal diseases (IPD) in Chinese children remain uncharacterized. This study aims to identify the resistance genes associated with erythromycin resistance and to determine the genetic relationships of IPD isolates in Chinese children.

Methods
A total of 171 S. pneumoniae strains were isolated from 11 medical centers in China from 2006 to 2008. All the isolates were characterized via serotyping and antibiotic susceptibility determination. The erythromycin-resistant isolates were further characterized via ermB and mefA gene detection, multi-locus sequence typing analysis, and pulsed-field gel electrophoresis.

Results
A total of 164 (95.9%) isolates showed resistance to erythromycin, of which 162 strains with high high-level resistance (MIC ≥ 256 μg/ml). A total of 104 (63.4%) isolates carry the ermB gene alone, whereas 59 (36.0%) harbor both ermB and mefA genes. Of the 59 strains, 54 were of serotypes 19A and 19F and were identified as highly clonal and related to the Taiwan19F-14 clone.

Conclusions
The erythromycin resistance rate in IPD isolates is significantly high and is predominantly mediated by the ermB gene. Isolates that carry both ermB and mefA genes are predominantly of serotypes 19A and 19F.
Endodontic bacteria from primary and persistent endodontic lesions in Chinese patients as identified by cloning and 16S ribosomal DNA gene sequencing
Authors: LI Xin , ZHU Xiao-fei , ZHANG Cheng-fei , Cathro Peter , CJ Seneviratne , SHEN Song 
Published: January 2024

Background
Few literatures pertain to the 16S ribosomal DNA (16S rDNA) analysis of bacteria contributing to primary and persistent endodontic lesions, with no information available for the Chinese population. As such, we investigated endodontic bacteria associated with primary and persistent endodontic lesions in adult Chinese patients living in Beijing, China using 16S rDNA gene sequencing techniques.

Methods
Endodontic microbial samples were obtained from fourteen adult Chinese patients and subjected to DNA extraction. Pllymerase chain reaction (PCR) products were cloned and 100 clones from each generated library were randomly selected. Purified plasmid DNA with 16S rDNA gene inserts was sequenced, and the sequences were searched against GenBank databases using the BLASTN algorithm. Only significant identification with the highest-scored BLAST result and 99% minimum similarity was considered for phylotyping.

Results
More than 150 taxa were obtained. Primary endodontic infection was mainly associated with Burkholderia cepacia, Actinomyces, Aranicola spp. and Streptococcus sanguinis, whilst Burkholderia cepacia was predominant in the persistent endodontic infections.

Conclusion
There is a difference in the species profile associated with endodontic infections of Chinese patients living in Beijing in comparison to other geographical or ethnic reports.
The “time-window” effect of early allergen exposure on a rat asthma model
Authors: HU Yan , LIU Ping , LI Hai-chao , WANG Yue-dan 
Published: January 2024

Background
The hygiene hypothesis has been proposed to explain the pathogenesis of asthma. Allergen exposure was shown to inhibit asthma in an animal model. But the optimal timing of allergen exposure remains unclear. This study aims to explore the time effcct of allergen exposure and the possible mechanisms.

Methods
Neonate Wistar rats were randomly divided into asthma group, control group and day 1, day 3, day 7, and day 14 groups. The day 1, day 3, day 7 and day 14 groups were injected with ovalbumin (OVA) subcutaneously on days 1, 3, 7 and 14 after birth, respectively. Six weeks later, all groups, except the control group, were sensitized and stimulated with OVA to make the asthma model. We observed the pulmonary pathologic changes, detected the regulatory T cells, and CD28 expression level in thymus and spleen by flow cytometry.

Results
The asthmatic inflammation in the day 1, day 3 and day 7 groups, but not the day 14 group, was alleviated. The asthma group and day 14 group had lower proportions of regulatory T cells in the thymus compared with the control group, day 1, day 3, and day 7 groups. There was no significant difference in the CD28 expression levels on the regulatory and conventional T cells among groups. But the control group and the day 1, day 3, and day 7 groups had relatively higher proportions of CD28 positive regulatory T cells in the thymus than the day 14 group and the asthma group.

Conclusions
There is a “time-window” for early allergen exposure. The impairment of regulatory T cells may promote the development of asthma. Allergen exposure in the “time-window” can make the thymus produce normal quantity of regulatory cells. The CD28 signal on regulatory T cells may participate in the production of regulatory T cells.
Genetic counseling, prenatal screening and diagnosis of Down syndrome in the second trimester in women of advanced maternal age: a prospective study
Authors: QI Qing-wei , JIANG Yu-lin , ZHOU Xi-ya , LIU Jun-tao , YIN Jie , BIAN Xu-ming 
Published: January 2024

Background
The incidence of autosomal trisomy in livebirths is strongly dependent on maternal age. Special consideration is given to the provision of prenatal screening and cytogenetic testing to women of advanced maternal age (AMA). The aim of this study was to evaluate the effectiveness of second trimester prenatal screening and amniocentesis for Down syndrome (DS) and compare the trends of choice of screening and amniocentesis among AMA women.

Methods
A total of 5404 AMA patients with natural singleton pregnancy were recruited for this prospective study from January 2008 to December 2010. The gestational weeks were from 15 weeks to 20+6 weeks. The patients referred were grouped into a screening group (2107 cases) and an amniocentesis group (3297 cases) by their own decision. The prevalence of DS was compared between the two groups by chi-square test. Choice rates for each maternal age with trends were compared by regression analysis.

Results
There were 18 cases of fetal DS detected in the screening group with a prevalence of 8.54‰ (18/2107). Twenty-five cases of fetal DS were diagnosed in the amniocentesis group with a prevalence of 7.58‰ (25/3297). No statistical difference was observed in the prevalence of DS between the screening and amniocentesis group (P=0.928). The invasive testing rate for DS in the amniocentesis group was 5.54 times higher than that of the screening group (1/131.88 vs. 1/23.78). With the increase of the maternal age, the choice of amniocentesis increased while the choice of the screening showed an opposite trend. The choice of the AMA women between the screening and amniocentesis was significantly age relevant (P=0.012).

Conclusions
The second trimester serum screening in combination with maternal age was more effective than maternal age alone to screen for DS. We suggest educating the patients by recommending AMA women be informed of both screening and amniocentesis options.
Splenectomy protects experimental rats from cerebral damage after stroke due to anti-inflammatory effects
Authors: ZHANG Bing-jun , MEN Xue-jiao , LU Zheng-qi , LI Hai-yan , QIU Wei , HU Xue-qiang 
Published: January 2024

Background
A recent study demonstrated that the inflammatory response accompanying necrotic brain injury played an important role in stroke. Thus, inhibition of this response may help to stop the expansion of infarcts. It has been also shown that the spleen, a major peripheral immune organ, plays a role in stroke-induced immune responses. This study aimed to establish rat models of middle cerebral artery occlusion (MCAO) and to investigate the effect of splenectomy and possible mechanisms in that rat models.

Methods
Infarct size in a stroke model was measured with the Nissl body staining method, numbers of inflammatory cells in ischemic regions were detected by immunofluorescence staining, and inflammatory factors were assayed by enzyme-linked immunosorbent assay and real-time polymerase chain reaction (PCR) in brain homogenates and sera. The significance of differences was determined by one-way analysis of variance (ANOVA) followed by the least significant difference post hoc test.

Results
Infarct size in the brain of rats that underwent splenectomies 2 weeks before permanent MCAO ((34.93±3.23)%) was over 50% smaller than that of rats subjected to the stroke surgery alone ((74.33±2.36)%, P <0.001; (77.30±2.62)%, P <0.001). Lower numbers of T cells, neutrophils, and macrophages in brain tissue and lower levels of pro-inflammatory cytokines, such as interleukin (IL)-1β and tumor necrosis factor (TNF)-α, were observed in rats that underwent splenectomies, compared with the two other groups, but splenectomized rats showed higher levels of the anti-inflammatory factor IL-10 in the brain.

Conclusion
The mechanism(s) by which splenectomy protects brain from damage induced by stroke may correlate with the decreased numbers of inflammatory cells and changes in inflammatory cytokines.
Efficacy of glycyrrhizin combined with cyclosporine in the treatment of non-severe aplastic anemia
Authors: REN Cui-ai , LI Yan-xiang , CUI Jing-ying , SHENG Zhi-xin , RAN Xue-hong , WANG Bao-hong , ZHANG Mao-hong 
Published: January 2024

Background
Cyclosporine A (CsA) has been widely used in the treatment of aplastic anemia (AA), but the application of CsA was limited in patients who had liver diseases or abnormal liver function due to its liver toxicity. Glycyrrhizin has long been used in China in the treatment of various liver diseases to lower transaminases. In this study, we observed the efficacy and safety of glycyrrhizic acid combined with CsA in the treatment of newly diagnosed patients with non-severe AA (NSAA).

Methods
A total number of 76 patients with newly diagnosed NSAA were enrolled into the study at our hospital between July 2005 and June 2010. The patients were divided randomly into two groups: the glycyrrhizin-treatment group (group A) and the control group (group B) with 38 patients in each group. All patients received 3-5 mg·kg-1·d-1 CsA for at least 4 months and were treated either with or without glycyrrhizin for 4 months.

Results
sixty-eight patients were eligible for evaluation. In the control group, 9.09% patients (n=3) achieved a complete response while 51.52% (n=17) attained a partial response. The overall response rate was 60.61% (n=20). The remaining 13 patients (39.39%) did not have any response. In the glycyrrhizin-treatment group, complete response rate was 20% (n=7) and partial response rate was 62.86% (n=22). The overall response rate was 82.86% (n=29) and the non-response rate was 17.14% (n=6). Response rate was significantly increased with the addition of glycyrrhizin to CsA compared with CsA alone (P<0.05).

Conclusion
The combination of glycyrrhizin and cyclosporine regimen was an effective treatment for NSAA in terms of improvement of response rate, reduction in CsA-related liver injury, and attenuation of severity of nausea and other adverse events in the treatment of patients with NSAA.
Effects of competitive and noncompetitive 5f-reductase inhibitors on serum and intra-prostatic androgens in beagle dogs
Authors: ZHAO Xiao-feng , YANG Yong , WANG Wei , QIU Zhi , ZHANG Peng , WANG Biao 
Published: January 2024

Background
5α-Reductase inhibitors (5α-RI) act by inhibiting the conversion of testosterone to dihydrotestosterone (DHT), thereby preventing DHT induced benign prostatic hyperplasia. The existing 5α-RIs can be classified into two types: competitive and noncompetitive. Currently, limited evidence is available concerning the effect differences between the two types of 5α-RI on androgens. The purpose of this study was to assess the effects of competitive and noncompetitive 5α-RIs on serum and intra-prostatic androgens in beagle dogs.

Methods
Twenty beagles with spontaneous benign prostatic hyperplasia were randomly allocated into two groups: epristeride group (n=10) in which beagles were treated with epristeride at 1 mg/kg once a day for 3 months, and finasteride group (n=10) in which beagles were treated with finasteride at 1 mg/kg once a day for 3 months. The levels of intra-prostatic testosterone and DHT were measured before treatment and on day one after three months medication. Serum levels of testosterone and DHT were measured at the same time points. Changes in androgen levels before and after treatment were analyzed, and comparisons were made within each treatment group and between treatment groups.

Results
After 3-month treatment, serum and intra-prostatic DHT levels all decreased significantly in both the epristeride and finasteride groups. The change of DHT in serum was significantly higher in the finasteride group (-14% and -43% in epristeride and finasteride groups respectively, with P<0.001); however there was no significant difference in the changes of intra-prostatic DHT between the two groups (-47% and -51% in epristeride and finasteride groups, respectively, P=0.304). The decreases in DHT levels were accompanied by reciprocal increases in serum and intra-prostatic testosterone levels. Changes of testosterone were significantly higher in finasteride group both in serum (20% and 42% in epristeride and finasteride groups, respectively, P<0.001) and in prostate tissue (18% and 29% in epristeride and finasteride groups, respectively, P=0.004).

Conclusions
Two types of 5T-RI have similar effects in reducing DHT in prostate tissue in beagles. Competitive 5α-RI may reduce serum DHT to a greater scale, and significantly increase testosterone in beagle serum and prostate.
Brain natriuretic peptide and copeptin levels are associated with cardiovascular disease in patients with chronic kidney disease
Authors: LI Xin , YANG Xin-chun , SUN Qian-mei , CHEN Xiang-dong , LI Yan-chun 
Published: January 2024

Background
Cardiovascular disease (CVD) is the leading cause of death in patients with end-stage renal disease (ESRD). We explored the relationship between CVD, plasma brain natriuretic peptide (BNP) and copeptin in non-dialysis patients with chronic kidney disease (CKD).

Methods
BNP and copeptin were measured using ELISA in 86 non-dialysis patients with different degrees of CKD and in 20 control patients. The effects of BNP, copeptin levels and other biochemical indices on carotid ultrasound echocardiography and CVD history were determined using correlation analysis.

Results
BNP and copeptin levels were significantly higher in the CKD group than in the control group. Both indices increased progressively, in parallel with the decline in glomerular filtration rate (GFR). BNP levels were (184.25±65.18) ng/L in early phase CKD, (975.245±354.09) ng/L in middle phase CKD, and (1463.51±614.92) ng/ml in end phase CKD compared with levels of (101.56±42.76) ng/L in the control group (all P <0.01). Copeptin levels in the middle phase ((20.36±9.47) pmol/L) and end phase groups ((54.26±18.23) pmol/L were significantly higher than in the control group ((9.21±2.64) pmol/L; both P <0.01). There was no difference in copeptin levels between early phase CKD ((10.09±5.23) pmol/L) and control patients. Stepwise multiple regression analysis identified GFR, intima-media thickness (IMT), left ventricular hypertrophy (LVH), and previous history of CVD as independent risk factors for elevated BNP and copeptin levels.

Conclusion
BNP and copeptin appear to provide sensitive biological markers for the evaluation of atherosclerosis in non-dialysis patients with CKD.
HIV infection among new synthetic drug abusers: a pilot study in Beijing
Authors: LI Ping , CHEN Xiao , XIE Pei-yan , CHU Ping , LI Dong-liang , LI Qian-qian , SHAO Yi-ming , JIA Zhong-wei 
Published: January 2024

Background
Following the increased human immunodeficiency virus (HIV) notification (infection) rates via sexual transmission and increased abuse of new synthetic drugs instead of heroin in China, a study on HIV infections and risk factors among synthetic drugs and heroin users in Beijing was conducted to provide a cue for further development of targets and strategies of HIV/AIDS control and prevention for different drug populations.

Methods
A total of 428 subjects including 224 heroin users and 204 new synthetic drug users was recruited from communities in Beijing by convenience sampling. A χ2 test was used to compare HIV and syphilis infections between the two subpopulations. Logistic regression models were used to evaluate factors related to HIV, syphilis infections and abuse of synthetic drugs.

Results
Unbalanced distributions of demographics were detected between the two subpopulations. Compared with heroin users, most users of synthetic drugs were migrants, single and of younger age (age ≤30 years). Ten HIV infections and twenty-four syphilis infections were confirmed among 428 subjects. No significant difference in HIV infection was found between the two subpopulations (crude odds ratio (OR) =0.46, 95% confidence interval (CI): 0.07-15.80 and adjusted odds ratio (AOR) =1.26, 95% CI: 0.09-18.28) while four times as many syphilis infections were identified among users of synthetics drugs (AOR=3.92, 95% CI: 1.06-14.56). HIV and syphilis infections appeared to work synergistically. The migrants who were of Han ethnicity, single and who had stayed in Beijing for more than six months were more likely to abuse synthetics drugs.

Conclusions
The new synthetic drug users and heroin users are different subpopulations. We optimistically speculate that HIV has not yet been introduced into the former in Beijing, but considering higher syphilis infections in synthetic drug users and the role of syphilis in HIV infection, synthetic drug users, as a possible and important driver of the HIV/AIDS epidemic in Beijing, should be paid more attention in HIV prevention and control strategies.
Exposure to heat-inactivated Trichophyton rubrum resulting in a limited immune response of human keratinocytes
Authors: HUANG Xiao-qiang , YI Jin-ling , YIN Song-chao , CHEN Rong-zhang , LI Mei-rong , GONG Zi-jian , LAI Wei , CHEN Jian 
Published: January 2024

Background

Trichophyton rubrum (T. rubrum) represents the most important agent of dermatophytosis in humans. T. rubrum infection causes slight inflammation, and tends to be chronic and recurrent. It is suggested that it may result from the failure of epithelial cells to recognize T. rubrum effectively and initiate effective immune responses. The C-type lectin receptors (CLR) and toll-like receptors (TLR) are the two major pattern recognition receptors (PRRs) that recognize fungal components. Therefore, the purpose of the study was to analyze the expression of those PRRs and the cytokines in HaCaT cells stimulated with heat-inactivated T. rubrum conidia and hyphae, respectively.

Methods
HaCaT cells were unstimulated or stimulated with heat-inactivated T. rubrum conidia and hyphae (1×106 and 1.5×105 colony-forming unit (CFU) in 2 ml medium, respectively) for 6, 12 and 24 hours. The mRNA expression of PRRs involved in recognizing fungal pathogen-associated molecular patterns (PAMPs) and signaling molecules were measured by quantitative reverse transcription polymerase chain reaction (RT-PCR). Meanwhile, surface toll-like receptor (TLR) 2, TLR4 and Dectin-1 were analyzed by fluorescence-activated cell sorter (FACS) 24 hours after treatment. The cytokines were detected in cell culture supernatants of HaCaT cells in 12 and 24 hours after treatment.

Results
HaCaT cells constitutively expressed mRNA of membrane-bound TLR1, 2, 4 and 6, Dectin1 and DC-SIGN, but not Dectin-2 or Mincle. Heat-killed T. rubrum did not significantly upregulate gene transcriptions of the PRRs of HaCaT cells. Heat-inactivated T. rubrum conidia significantly reduced the surface expression of TLR2 and Dectin-1, and suppressed the secretions of interferon-inducible protein-10 (IP-10) and monocyte chemotactic protein-1 (MCP-1) of HaCaT cells, while heat-killed T. rubrum hyphae significantly induced the secretions of IP-10 and MCP-1.

Conclusion
The cell-wall antigens of T. rubrum fail to activate transcriptional expression of PRRs and induce a lower immune response of HaCaT cells by limited cytokines secretion.
JNK phosphorylation promotes degeneration of cervical endplate chondrocytes through down-regulation of the expression of ANK in humans
Authors: XU Hong-guang , SONG Jun-xing , CHENG Jia-feng , ZHANG Ping-Zhi , WANG Hong , LIU Ping , LÜ Kun , ZHONG Min 
Published: January 2024

Background
C-Jun N-terminal kinase (JNK) signaling pathway and ankylosis gene (ANK) play a critical role in endplate chondrocytes degeneration. The purpose of this study was to investigate whether the expression levels of ANK was associated with the activation of JNK.

Methods
Cartilage endplates of 49 patients were divided into the control group (n=19) and the experimental group (n=30). The patients in the control group were graded 0 and those in the experimental group were graded I-III according to Miller’s classification. Endplate chondrocytes were isolated by enzyme digestion and cultured in vitro. The inverted phase contrast microscope, teluidine blue staining, HE staining, real time RT-PCR, and MTT were used to observe morphological appearances, biological characteristics, and growth curve of endplate chondrocytes from the cartilage endplate of the two groups. Real time RT-PCR and Western blotting were used to analyze the mRNA and protein expression levels of associated factors in the degeneration process in the cultured endplate chondrocytes with or without subjected SP600125.

Results
The expression levels of type II collagen, aggrecan, and ANK in endplate chondrocytes of experimental group were lower than that of control group and phosphorylation level of JNK in the experimental group which was higher than that in the control group. Application of JNK phosphorylation inhibitor to degeneration chondrocytes resulted in a marked decrease in the phosphorylation level of JNK and a significant increase in the expression levels of type II collagen, aggrecan, and ANK.

Conclusion
The degeneration of the human cervical endplate chondrocytes might be promoted by JNK phosphorylation by down-regulating the expression of ANK