bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetic environment of β-lactamase genes of extended-spectrum β-lactamase-producing Klebsiella pneumoniae isolates from patients with lower respiratory tract infection in China
Authors: Lin Liu , Xiaorong Wang , Shuchang An , Xiangyan Zhang , Lin Chen , Yuqian Li , Li Xu , Yijie Zhang , Zhancheng Gao 
Published: January 2024

Background
Extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae (K. pneumoniae) is one of the most popular pathogens that cause refractory respiratory tract infection. The genetic environment, including insertion sequences and the types of promoter, plays a key role in exploration of the mechanism of prevalence and dismission of the ESBL-producing K. pneumoniae isolates. The aim of the investigation was to target analysis the genetic environment and promoter sequences of bla
CTX-M, bla
SHV and bla
TEM, the most popular β-lactamase genes harbored by ESBL-producing K. pneumoniae isolates.

Methods
From February 2010 to July 2011, 158 of 416 K. pneumoniae isolates producing ESBL from patients with lower respiratory tract infection were collected from seven tertiary hospitals from Beijing, Anhui, Fujian, Liaoning, Hebei and Inner Mongolia Autonomous Region in China. The genetic environment including promoters of 10 types of bla
CTX-M, 18 types of bla
SHV and 2 types of bla
TEM were analyzed by amplification and direct sequencing with various sets of PCR primers.

Results
ISEcp1 was located upstream of the 5' end of the bla
CTX-M gene in 130 (97.0%) out of 134 K. pneumoniae isolates harboring bla
CTX-M and provided a conserved promoter to bla
CTX-M. A non-coding sequence preceded by kdpC and recF was identified in all of the bla
SHV genes except bla
SHV-12 and bla
SHV-2a. IS26 was also found upstream of 1 bla
CTX-M-15, 10 bla
SHV-1 strains, 4 bla
TEM-1 and all of the bla
SHV-2,
bla
SHV-2a, bla
SHV-5 and bla
SHV-12. Eighty-seven of 91 strains harboring bla
TEM-1 carried a copy of Tn2 and IS26-bla
TEM-1 fragments were also detected in 4 strains. With respect to K. pneumoniae, the genetic environment of bla
CTX-M-38, bla
SHV-142 and bla
TEM-135 were firstly elaborated, and four kinds of novel genetic environment of bla
CTX-M-3, bla
CTX-M-15 and bla
TEM-1 have been detected as well.

Conclusions
Perfective implementation of the genetic environment information of β-lactamase gene needs to be further explored and supplemented. ISEcp1 and IS26 elements are widespread upstream of the bla
CTX-M, bla
SHV and bla
TEM genes and contribute to horizontal transmission and genetic expression.
Current advances in diagnostic methods of Acanthamoeba keratitis
Authors: Yuehua Wang , Xianmin Feng , Linzhe Jiang 
Published: January 2024

Objective
The objective of this article was to review the current advances in diagnostic methods for Acanthamoeba keratitis (AK).

Data sources
Data used in this review were retrieved from PubMed (1970–2013). The terms “Acanthamoeba keratitis” and “diagnosis” were used for the literature search.

Study selection
Data from published articles regarding AK and diagnosis in clinical trials were identified and reviewed.

Results
The diagnostic methods for the eight species implicated in AK were reviewed. Among all diagnostic procedures, corneal scraping and smear examination was an essential diagnostic method. Polymerase chain reaction was the most sensitive and accurate detection method. Culturing of Acanthamoeba was a reliable method for final diagnosis of AK. Confocal microscopy to detect Acanthamoeba was also effective, without any invasive procedure, and was helpful in the early diagnosis of AK.

Conclusion
Clinically, conjunction of various diagnostic methods to diagnose AK was necessary.
State of the art contemporary treatment of patients with ST elevation myocardial infarction: pre- and in-hospital organization, devices and drugs
Authors: Schoos Mikkel Malby , Mehran Roxana 
Published: January 2024

Objective
To review the presentation, diagnosis and recent developments in the pharmacological and invasive treatment of ST elevation myocardial infarction (STEMI) with a special focus on health-care organization in order to increase accessibility of primary percutaneous coronary intervention (PCI).

Data sources
Data were obtained from English publications on STEMI treatment. No formal systematic review was conducted, but an effort was made to be comprehensive.

Study selection
Studies were selected if they contained data relevant to the topic. Preferably, data from clinical randomized trials, meta-analyses, guidelines and a few recent reviews are referenced.

Results
The described clinical approach to acute myocardial infarction (AMI) has been a continuum of scientific results and translation into clinical practice over the last four decades since the advent of thrombolytic reperfusion. This has resulted in a dramatic in-hospital mortality decrease from 30% in the 1960s to the present 5%. The biggest survival benefits have undoubtedly been achieved after the advent of reperfusion strategies. In contemporary treatment of STEMI, additional treatment effects on survival have to be sought in the very early admission phase, as the current mortality hazard drops significantly after the first critical days to continuously very low levels after discharge.

Conclusions
Optimal treatment of STEMI patients is best performed with a widely accessible reperfusion strategy, preferably primary PCI, with contemporary peri-procedural anti-thrombotic treatment and device implantation. Accessibility of reperfusion strategies is increased by efficient STEMI networks applying prehospital triage with digital tele-transmission of electrocardiograms (ECGs) and seamless patient transitions between health-care unities. Efficient treatments of complicated STEMI with out-of hospital cardiac arrest and/or cardiogenic shock underline the necessity of structured referral systems, preferably immediately after the initial STEMI diagnosis.
Expression of a constitutively active prolactin receptor causes histone trimethylation of the p53 gene in breast cancer
Authors: Tan Dunyong , Tang Peizhi , Huang Jianjun , Zhang Jie , Zhou Weihua , Walker Ameae M. 
Published: January 2024

Background
Prolactin (PRL) is a pituitary polypeptide hormone characterized by multiple biological actions including stimulation of growth in the prostate and formation of secretory alveoli and stimulation of milk protein gene expression in the mammary gland. PRL exerts its effect by dimerizing its receptor (PRLR) on the plasma membrane and regulating gene expression through the JAK-Stat signal pathway. We have previously described a natural variant of the PRLR in which the S2 subdomain of the extracellular domain is missing (Delta S2). Delta S2 PRLRs are dimerized in the absence of PRL and have constitutive activity in the promotion of breast cancer cell growth. Enhancer of zeste homolog 2 (EZH2), as one of the histone-modifying enzymes, is a key factor regulating gene expression by epigenetic modification. We hypothesized that these constitutive activated Delta S2 PRLRs played a pathogenic role in breast cancer in part through alterations in the expression of EZH2 and the trimethylation of histone 3 on lysine 27 (H3K27Me3).

Methods
In order to verify the clinical significance and to establish the link between Delta S2 PRLR expression and epigenetic change, EZH2, H3K27Me3, and Delta S2 PRLR were detected in both normal and cancerous human breast tissues. Also, overexpression of Delta S2 PRLR in breast epithelial cells was achieved by infection with adenovirus carrying the cDNA. Western blotting and chromatin immunoprecipitation (ChIP assay) and acid histone extraction were applied to detect the expression of EZH2 and the trimethylation of histone 3, respectively.

Results
In breast tissue, higher EZH2 expression and higher H3K27Me3 were found associated with higher Delta S2 expression in breast cancer samples. In breast epithelial cells, overexpression of Delta S2 PRLR increased EZH2 methyltransferase mRNA and protein, induced EZH2 methyltransferase recruitment to chromatin, increased the trimethylation of H3K27Me3, and decreased the expression of p53 gene.

Conclusions
Delta S2 PRLR plays an important pathogenic role in breast cancer through epigenetic modification. Elevated expression of Delta S2 PRLR, achieved by alternate splicing of the pre-mRNA of the full-length form, is a new mechanism contributing to human breast cancer.
MiR-503 regulates cisplatin resistance of human gastric cancer cell lines by targeting IGF1R and BCL2
Authors: Wang Tongshan , Ge Gaoxia , Ding Yin , Zhou Xin , Huang Zebo , Zhu Wei , Shu Yongqian , Liu Ping 
Published: January 2024

Background
Studies have shown that the drug resistance of gastric cancer cells can be modulated by abnormal expression of microRNAs (miRNAs). We investigated the role of miR-503 in the development of cisplatin resistance in human gastric cancer cell lines.

Methods
MiR-503 expression was measured by quantitative real-time PCR. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and clonogenic assays were used to examine changes in cell viability and the drug resistance phenotype of cancer cells associated with upregulation or downregulation of the miRNA. A dual-luciferase activity assay was used to verify target genes of miR-503. Immunohistochemistry, Western blotting analysis, and a flow cytometric apoptosis assay were used to elucidate the mechanism by which miR-503 modulates drug resistance in cancer cells.

Results
MiR-503 was significantly downregulated in gastric cancer tissues and several gastric cancer cell lines. Additionally, downregulation of miR-503 in the cisplatin (DDP)-resistant gastric cancer cell line SGC7901/DDP was concurrent with the upregulation of insulin-like growth factor-1 receptor (IGF1R) and B-cell lymphoma 2 (BCL2) expression compared with the parental SGC7901 cell line. An in vitro drug sensitivity assay showed that overexpression of miR-503 sensitized SGC7901/DDP cells to cisplatin. The luciferase activity of reporters driven by IGF1R and BCL2 3′-untranslated regions in SGC7901/DDP cells suggested that IGF1R and BCL2 were both direct target genes of miR-503. Enforced miR-503 expression in SGC7901/DDP cells reduced expression of the target proteins, inhibited proliferation, and sensitized the cells to DDP-induced apoptosis.

Conclusion
Our findings suggest that hsa-miR-503 modulates cisplatin resistance of human gastric cancer cells at least in part by targeting IGF1R and BCL2.
Influence of tube voltage on digitized image qualityof patients exposed to occupational dust: phantoms and clinical studies
Authors: Xiaohua Wang , Dongsheng Liu , Xiao Xuan , Jianghui Duan , Huishu Yuan 
Published: January 2024

Background
High-voltage analog X-ray examination is a main tool for pneumoconiosis, which is challenged by digital radiography (DR). The tube voltage of DR chest films required for diagnosis and staging of pneumoconiosis is concerned technically. We investigated the influence of the tube voltage on chest X-ray DR image quality of patients exposed to occupational dust.

Methods
DR images of the CDRAD2.0model, an anatomical chest phantom, and 136 exposed workers were analyzed at different tube voltages by threereaders. Image quality factors (IQF) were calculated and compared using the CDRAD2.0 model. DR images of ten anatomic positions were scored against those of the high-kilovolt chest films in anatomical phantom and clinical cases, and differences in scores were analyzed.

Results
In the CDRAD2.0 model, all three readers had a minimal IQF at 120 kV (mean: 22.25 kV). The differences in the mean IQF of DR images at different tube voltages was significant (F=13.78, P<0.001). The IQF of DR imaging at 120 kV was similar to high kilovolt analog imaging (t=-0.58, P>0.05). In the anatomic phantom and clinical cases, the DR images at 120 kV were closest in anatomical detail to the high kV analog images, and the means were similar (P>0.05).

Conclusions
Among different tube voltages, DR image quality is closest to the high kilovolt analog images at 120 kV in patients exposed to occupational dust.
Reliability of pressure cuff induced transient limb ischemia in conscious rabbits
Authors: Zhang Nanrong , Zheng Wanjun , Wen Yi , Hu Qiongyu , Jin Sanqing 
Published: January 2024

Background
The protective effects of transient limb ischemia (TLI) induced by several cycles of intermittent pressure cuff inflation and deflation for a period have been widely investigated, however the reliability of this protocol has not been clearly verified. Our study aimed to investigate the reliability of pressure cuff induced TLI in conscious rabbits.

Methods
Eight New Zealand rabbits were subjected to TLI without anesthesia. TLI consisted of 3 cycles of ischemia and reperfusion induced by inflating the cuff placed on the left lower limb to 200 mmHg for 5 minutes followed by deflating the cuff for 5 minutes. Skin color, pulse oxygen saturation (SpO2), pulse rate (PR), plethysmogram waveform (Pleth), and ultrasound detection of the blood flow in the extremity distal to the ischemic segment were observed to confirm ischemia and reperfusion during TLI. The frequency of severe limb movement during TLI was also recorded to assess the amenability of this protocol in conscious rabbits.

Results
The skin color of the extremity distal to the ischemic segment changed from bright red to dark purple after inflating the cuff to 200 mmHg, and returned to normal after cuff deflation. Pleth, PR and SpO2 disappeared during ischemia and restored during reperfusion in the monitor. Blood flow of the left posterior tibial artery was completely blocked by a pressure of 200 mmHg during ischemia, and recovered immediately after cuff deflation. The frequency of severe limb movement in supine position was higher than that in prone position (P<0.05), but there was no severe limb movement that could result in disturbance to ischemia when the rabbits were placed in prone position.

Conclusion
Pressure cuff inflating to 200 mmHg for 5 minutes and deflating for 5 minutes is a reliable regimen to induce TLI in conscious rabbits.
Effects of substance P on growth of fibroblast-like cells derived from bile duct: an in vitro cell culture study
Authors: Yuanhu Tian , Guangyun Yang , Xiaoqing Zhang , Wei Shen , Jiahong Dong , Zhi Xu 
Published: January 2024

Background
The possible role of substance P (SP) during wound healing has been the primary research focus in recent years, but its effect on the healing process after bile duct injury is little understood. This study aimed to investigate the effects of SP on growth of fibroblast-like cells derived from rabbit bile duct.

Methods
Fibroblast-like cells derived from rabbit bile duct were identified and divided randomly into control and experimental groups. SP-treated cells at different concentrations of 10-9-10-5 mol/L and control group were incubated, respectively, for 48 hours. After incubating, the effects of SP on cell proliferation were assessed by cell counts and MTT test. Apoptosis rate (AR) of cells was measured by flow cytometry.

Results
Cultured rabbit bile duct cells were fibroblast-like in morphology, and these cells were stained positively for vimentin and negatively for desmin. After SP was added to nonconfluent cells for 48 hours, cell numbers were significantly increased in experimental groups than in controls (P <0.05). The maximum stimulation of cell proliferation was achieved at SP of 10-5 mol/L. Bile duct fibroblast-like cells in the SP group showed a higher proliferating activity and lower AR than those in the control group or in the SP + Spantide group (P <0.05). Spantide partly inhibited the effects of SP on fibroblastlike cells. Examination under transmission electron microscopy revealed rough endoplasmic reticulum and prominent Golgi complexes after SP treatment.

Conclusions
SP has a growth regulatory property on cultivated bile duct fibroblast-like cells in vitro, suggesting that SP may involve in wound healing after bile duct injury by promoting wound fibroblast proliferation and inhibiting apoptosis and participate in pathological scar formation.
Progress in various crosslinking modification for acellular matrix
Authors: Haitang Yang , Qiang Tan , Heng Zhao 
Published: January 2024

Objective
To review the current crosslinking strategies for acelluar matrix scaffold, laying the foundation for subsequent experiment.

Data sources
Data were mainly obtained from recent papers published in PubMed or indexed by Web of Science, with keyword like crosslinking.

Results
Various crosslinking strategies, including chemical, physical and biological methods, have been introduced to facilitate the performance of fresh acellular matrix. Chemical crosslinking reagents, involved in synthetic and naturally derived agents, need to be eliminated before implantation in case of their potential biotoxicity, although several crosslinking agents with less toxicity and specific characteristics have been developed. Physical crosslinking methods present to be safe, additive-free and relatively controllable for rapid surface functionalization with no consideration of remaining radioactivity. Biological crosslinking strategies have attracted great interest, and have been demonstrated to enhance collagen-based crosslinking since their preparations do not need toxic or potentially biologically contaminated substances and can be carried out under physiological conditions.

Conclusions
Kinds of crosslinking methods with its potential advantages have been developed to modify raw acelluar matrix, of which the performance are promising after being crosslinked by several crosslinking treatments. Further preclinical and clinical evaluations should be taken to vertify their safety and efficacy for the tissues and organs substitutes in tissue and regenerative medicine.
Prevalence of stroke and metabolic disorders in the middle-aged and elderly Chinese with type 2 diabetes
Authors: Xuebing Zhang , Yiming Mu , Wenhua Yan , Jianming Ba , Hongmei Li 
Published: January 2024

Background
Stroke is now the most prevalent and debilitating disease affecting diabetic population in China. The study aimed to investigate the prevalence of stroke and metabolic disorders in the middle-aged and elderly Chinese with type 2 diabetes.

Methods
A total of 4 629 subjects with type 2 diabetes (males: 1 917; females: 2 712) aged ≥ 40 years from Shijingshan district, Beijing, China from November 2011 to August 2012 were included in the study. Data on demographic information, lifestyle, history of diabetes mellitus, stroke, coronary heart disease, hypertension, and dyslipidemia were collected. The oral glucose tolerance test or a standard meal test was performed. Non-fatal stroke was reported by the subjects. The 2-tailed test was used, and P <0.05 was regarded as statistically significant.

Results
Prevalence of stroke in the subjects with type 2 diabetes was 5.5%. The prevalence of smoking, overweight or obesity, hypertension, and dyslipidemia was 41.0%, 65.8%, 67.4%, and 52.0% in males, and 2.2%, 65.5%, 69.5%, and 57.6% in females. Multivariate Logistic regression analysis showed that increased age, hypertension, diabetic duration, and overweight or obesity were positively correlated with stroke in the population with type 2 diabetes, whereas high-density lipoprotein cholesterol level was negatively correlated with stroke. After adjustment for age and gender, the odds ratio values of stroke in subjects having 1, 2 or ≥3 of 4 risk factors, including smoking, overweight or obesity, hypertension and dyslipidemia, were 2.302 (95% CI: 0.789–6.712), 4.089 (95% CI: 1.470–11.373), 6.023 (95% CI: 2.176–16.666), compared with subjects without any of the above 4 risk factors.

Conclusions
The prevalence of stroke was higher in middle-aged and elderly Chinese with type 2 diabetes than that in the general population. With the aggregation of risk factors, the prevalence of stroke increased.
Strabismus surgery distribution during 10-year period in a tertiary hospital
Authors: Yonghong Jiao , Yunting Zhu , Zhen Zhou , Ying Jie , Jinghui Wang , Wei Lu , Xiao Wu , Mengmeng Kan , Guohong Zhao 
Published: January 2024

Background
There is no large population-based study of the distribution and changing trend of strabismus surgeries in China. This study aimed to investigate the distribution and the changing trend of strabismus surgery in a tertiary hospital of China.

Methods
A retrospective study of all the strabismus surgeries performed in Beijing Tongren Eye Center from 2003 to 2012 was carried out. Characteristics analyzed included the type of strabismus, age, and gender.

Results
Totally 26 524 strabismus surgeries were performed in Tongren Eye Center during the 10-year period. The number of surgeries increased steadily from 1 507 in 2003 to 3 482 in 2008 and slightly decreased to 3 124 in 2009, but there was a sharp drop to 2 569 in 2010 and then kept relatively steady at 2 760 in 2011 and 2 463 in 2012. Intermittent exotropia (30.3%) was the most common among all kinds of strabismus. The number of strabismus surgeries performed on children under 12 years of age (43.60%) was significantly higher than those of the other age groups (P <0.05). Unilateral superior oblique paralysis was the most common subtype of paralytic strabismus (8.64%).

Conclusions
The type distribution of strabismus surgery has changed during the recent decade. The age and type distribution of different strabismus remained basically constant, among which intermittent exotropia was the most common.
Hypoxia-inducible factor-1α and semaphorin4D genes involved with tumor-associated macrophage-induced metastatic behavior and clinical significance in colon cancer
Authors: Linjun Mu , Jinshen Wang , Yuezhi Chen , Leping Li , Xiaobo Guo , Sheng Zheng , Changqing Jing 
Published: January 2024

Background
Hypoxia promotes tumor angiogenesis and hypoxia-inducible factor-1 alpha (HIF-1α) plays a pivotal role in this process. Recently identified pro-angiogenic factor, semaphorin4D (Sema4D) also promotes angiogenesis and enhances invasive proliferation in some tumors. Furthermore, tumor-associated macrophages (TAMs) can increase the expression of HIF-1α and Sema4D in cancer cells and thus influence tumor growth and progression. The purpose of this study was to evaluate the effect of TAMs on the expression of Sema4D and HIF-1α and the impact of biologic behavior in colon cancer cells.

Methods
Immunohistochemistry was used to analyze HIF-1α and Sema4D expression in 86 curatively resected colon cancer samples and 52 normal colon tissues samples. The relationship between their expression and clinicopathological factors was analyzed. Furthermore, macrophage-tumor cell interactions, such as metastasis, angiogenesis, were also studied using in vitro co-culture systems. Statistical analysis was performed using SPSS 17.0 software (SPSS Inc., USA). Differences between two groups were analyzed with Student's t test.

Results
HIF-1α (58%) and Sema4D (60%) were expressed at a significantly higher level in tumors than in normal tissues (P <0.01, for both). Furthermore, HIF-1α and Sema4D expression was significantly correlated with lymphatic metastasis, specific histological types and TNM stages (P <0.05), but not with age and tumor size (P >0.05). Sema4D expression was correlated with that of HIF-1α (r=0.567, P <0.01). TAMs markedly induced HIF-1α and Sema4D expression in colon cancer cells and subsequently increased their migration and invasion.

Conclusions
HIF-1α and Sema4D expression are closely related to lymphatic metastasis, specific histological types and TNM stages in colon cancer. Furthermore, TAMs promote migration and invasion of colon cancer cells and endothelial tube formation, possibly through up-regulation of HIF-1α and Sema4D.