The Application of Aptamer and Research Progress in Liver Disease

Aptamers, as a kind of small-molecule nucleic acid, have attracted much attention since their discovery. Compared with biological reagents such as antibodies, aptamers have the advantages of small molecular weight, low immunogenicity, low cost, and easy modification. At present, aptamers are mainly used in disease biomarker discovery, disease diagnosis, treatment, and targeted drug delivery vectors. In the process of screening and optimizing aptamers, it is found that there are still many problems need to be solved such as the design of the library, optimization of screening conditions, the truncation of screened aptamer, and the stability and toxicity of the aptamer. In recent years, the incidence of liver-related diseases is increasing year by year and the treatment measures are relatively lacking, which has attracted the people's attention in the application of aptamers in liver diseases. This article mainly summarizes the research status of aptamers in disease diagnosis and treatment, especially focusing on the application of aptamers in liver diseases, showing the crucial significance of aptamers in the diagnosis and treatment of liver diseases, and the use of Discovery Studio software to find the binding target and sequence of aptamers, and explore their possible interaction sites.

The roles of ETS transcription factors in liver fibrosis

E26 transformation specific or E twenty-six (ETS) protein family consists of 28 transcription factors, five of which, named ETS1/2, PU.1, ERG and EHF, are known to involve in the development of liver fibrosis, and are expected to become diagnostic markers or therapeutic targets of liver fibrosis. In recent years, some small molecule inhibitors of ETS protein family have been discovered, which might open up a new path for the liver fibrosis therapy targeting ETS. This article reviews the research progress of ETS family members in the development liver fibrosis as well as their prospect of clinical application.

Comprehensive evaluation of factors that induce gingival enlargement during orthodontic treatment: A cross-sectional comparative study

Background

Gingival enlargement (GE) is one of the most common soft tissue problems encountered during fixed orthodontic treatment. Aims: This study aimed to evaluate the factors affecting GE in adolescents and young adults, compared with their normal peers.

Subjects and Methods

This is a cross-sectional comparative study. The sample consisted of 329 subjects (ages 10-30 years) of both genders, which was divided into four main groups: The control group (G0) with no orthodontic treatment; subjects who underwent orthodontic treatment were divided according to treatment duration into G1 (4-12 months), G2 (13-24 months), and G3 (>24 months). The clinical examinations included the level of debris, calculus (simplified oral hygiene), and GE indices. Regression analyses were used to assess the GE association in all the studied groups.

Results

The mean GE score increased significantly with increased treatment duration (0.42 ± 0.29 for G0 and 1.03 ± 0.52 for G3). GE scores of the lower arch were significantly higher in the anterior segment than in the posterior segment among all treatment groups. Regression analysis revealed that gender, age, oral hygiene, and treatment duration had a significant effect on GE (P < 0.05), while angle classification, overjet, overbite, treatment stage, bracket type, and therapeutic extraction did not show significant associations (P > 0.05).

Conclusion

Gender, age, oral hygiene, and treatment duration were the most important risk factors for GE during fixed orthodontic treatment.

[Gene analysis and clinical features of MYH9-related disease]

Objective: To identify gene variants and investigate clinical features of nonmuscle myosin heavy chain 9-related disease (MYH9-RD). Methods: In this retrospective study, the data of patients with MYH9-RD admitted to Shenzhen Children's Hospital from July 2017 to September 2020 were extracted. The gene variants, clinical features and laboratory tests results were summarized. Results: Among the 6 children, 4 were males and 2 were females, aged 4.0 (0.5-7.6) years. Main clinical manifestations included thrombocytopenia (6 cases), epistaxis (3 cases), petechias (2 cases), traumatic hematoma (1 case), and abnormal liver enzymes (1 case). One patient had no family history, and the other 5 cases were pedigrees. Two pedigrees (2 cases) had long-term microscopic hematuria, one pedigree (2 cases) had history of early cataract, and three pedigrees (5 cases) had chronic mild elevation of liver enzymes. Four MYH9 gene variants were found in 12 patients, including c.2104C>T(p.R702C) in exon 17, c.4270G>A(p.D1424N) in exon 31, c.5521G>A (p.E1841K) in exon 39, and c.5797C>T (p.R1933X) in exon 41. According to the family pedigrees analysis, except for the case of variant in exon 17 which was spontaneous mutation with no family history, the other variants were from their father or mother. The complete blood count results showed a decreased platelet number in these patients, and the counting results of the automated hematology analyzer were significantly lower than that of manual counting method ((33.4±17.2) × 10⁹ vs. (60.4±21.0) × 10⁹/L,t=-5.83, P<0.05). The examination of the peripheral blood smear revealed the presence of thrombocytopenia with giant platelets and granulocyte inclusion bodies. The MYH9 gene variant (R702C) located at the N-terminus head domain of non-muscle myosin heavy chain ⅡA (NMMHC-ⅡA), which has ATPase activity, led to severe reduction of platelet number (<20×10⁹/L) and obscure granulocyte inclusion bodies. However, higher platelet numbers (40×10⁹-80×10⁹/L) and obvious granulocyte inclusion bodies were observed in patients with tail-position mutations at C-terminus. Conclusions: The clinical phenotypes of MYH9-RD were variable. The mutations in certain regions of MYH9 gene were related to platelet count and granulocyte inclusion bodies. MYH9-RD should be considered in individuals with unknown etiology and persistent thrombocytopenia which is non-responsive to conventional treatment, regardless of family history. Complete blood count and blood smear morphology examinations are the first steps to screen and diagnose the disease. The laboratory should pay attention to the morphological review rules and standardized reports.

Distinguishable Prognostic miRNA Signatures of Head and Neck Squamous Cell Cancer With or Without HPV Infection

Since their discovery in the 1990’s, microRNAs (miRNA) have opened up new vistas in the field of cancer biology and are found to have fundamental roles in tumorigenesis and progression. As head and neck squamous cell carcinoma (HNSCC) with positive human papillomavirus (HPV+) is significantly distinct from its HPV negative (HPV−) counterpart in terms of both molecular mechanisms and clinical prognosis, the current study aimed to separately develop miRNA signatures for HPV+ and HPV− HNSCC as well as to explore the potential functions. Both signatures were reliable for the prediction of prognosis in their respective groups. Then Enrichment analysis was performed to predict the potential biological functions of the signatures. Importantly, combining previous studies and our results, we speculated that HPV+ HNSCC patients with low signature score had better immunity against the tumors and enhanced the sensitivity of therapies leading to improved prognosis, while HPV− HNSCC patients with high signature score acquired resistance to therapeutic approaches as well as dysregulation of cell metabolism leading to poor prognosis. Hence, we believe that the identified signatures respectively for HPV+ and HPV− HNSCC, are of great significance in accessing patient outcomes as well as uncovering new biomarkers and therapeutic targets, which are worth further investigation through molecular biology experiments.

EZH2 promotes invasion and tumour glycolysis by regulating STAT3 and FoxO1 signalling in human OSCC cells

The enhancer of zeste homolog 2 (EZH2), known as a member of the polycomb group (PcG) proteins, is an oncogene overexpressed in a variety of human cancers. Here, we found that EZH2 correlated with poor survival of oral squamous cell carcinoma (OSCC) patients using immunohistochemistry staining. EZH2 overexpression led to a significant induction in tumour glycolysis, Epithelial‐mesenchymal transition (EMT), migration and invasion of OSCC cells. Conversely, silencing of EZH2 inhibited tumour glycolysis, EMT, migration and invasion in OSCC cells. Ectopic overexpression of EZH2 increased phosphorylation of STAT3 at pY705 and decreased FoxO1 expression, and FoxO1 expression was enhanced when inhibiting STAT3. In addition, EZH2 overexpression led to a significant decrease in FoxO1 mRNA levels in nude mice xenograft. These results indicated that regulation of EZH2 might have the potential to be targeted for OSCC treatment.

[Preclinical application of MR and fluorescent dual-modality imaging combined with photothermal therapy in HER-2 positive breast cancer]

Objective: To construct superparamagnetic iron oxide nanoparticles (SPIONs) coated on trastuzumab and indocyanine green (ICG) and then investigate whether the coated nanoparticles (NPs) targeted to human epidermal growth factor receptor-2 (HER-2) receptors on breast cancer cells in vitro and in vivo. Methods: The Fe(3)O(4)-trastuzumab-ICG NPs were constructed. And a series of characteristics of the NPs were evaluated. The uptake ability of SK-BR-3, a HER-2 positive breast cancer cell, was observed by transmission electron microscopy. Then the NPs were injected in the tail veins of SK-BR-3 xenograft tumor-bearing mice to observe the aggregation of NPs in the tumor sites by MRI and fluorescent imaging. Furthermore, when the NPs was gathered at the tumor sites, the near infrared thermal imaging system was used to monitor the tumor temperature after the near infrared radiation. Results: The successfully constructed Fe(3)O(4)-trastuzumab-ICG NPs had the size of (25.93±4.25) nm. The absorption peak was 828 nm, which was as same as the emission wavelength of ICG. The NPs had a high relaxation rate of approximately 107.65 mM(-1)·s(-1). The maximum temperature of NPs solution could reach to 57.8℃ after continuous near infrared laser irradiation. The transmission electron microscopy imaging revealed that the NPs could target and enter into the endoplasmic reticulum of SK-BR-3 cells. MRI analysis showed the lowest T(2) relaxation time in the tumor sites 24 h after tail vein injection of the NPs. The △T(2) of the tumor sites in the Fe(3)O(4)-trastuzumab-ICG group (30.7±4.8) ms was higher compared with that of control group (3.1±1.1) ms, Fe(3)O(4)-IgG-ICG group (4.4±0.9) ms and trastuzumab + Fe(3)O(4)-trastuzumab-ICG group (11.3±3.8) ms., respectively, all showing statistically significant differences (P<0.05). The fluorescence imaging revealed that the NPs was concentrated transiently in the intraperitoneal organs and tumor sites, then excreted into the bladder. After 24 h, there was an obvious aggregation in the tumor sites. The near infrared thermal imaging experiments showed that the temperature of tumor sites in Fe(3)O(4)-trastuzumab-ICG group could go up to 49.4℃ after continuous near infrared light irradiation. Conclusion: The newly constructed Fe(3)O(4)-trastuzumab-ICG NPs have the potential to act as a multifunctional imaging agent and a powerful tool for photothermal therapy for HER-2 positive breast cancer.

[Correlation between of aortic dissection onset and climate change]

Objective: To explore the relationship between the incidence of aortic dissection and climate change. Methods: The characteristics of 345 acute aortic dissection patients came from Beijing in Department of Vascular Surgery, Fu Wai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences, Peking Union Medical College from January 2005 to December 2015 were analyzed, retrospectively. There were 266 male and 79 female patients with a mean age of (49±12) years. There were 209 cases of Stanford type A aortic dissection, and 136 cases of type B. According to Fuwai aortic dissection classification: type A 8 cases, type B 95 cases, type Cp 13 cases, type Ct 187 cases, type Cd 40 cases, type D 2 cases. Meanwhile, monthly maximum temperature, minimum temperature, average temperature, average pressure, amount of rainfall, sunshine, relative humidity and other meteorological data were collected. Rank-sum test was used to analyze the difference of onset of aortic dissection in different seasons and months. Generalized additive models were implied to explore climate change and the onset of aortic dissection. Results: The onset of aortic dissection was related to season. Winter had higher morbidity compared to summer (M(Q(R)): 3(2) vs. 2(2), Z=1.97, P=0.05). The occurrence of aortic dissection was associated with month.December had the largest quantity, July had the least (2(3) vs. 2(1), Z=2.42, P=0.02). The mean temperature was statistically significant for indicating the change of aortic dissection onset. It meaned that onset probability was increased with the decrease of temperature (RR=1.01, 95%CI: 1.00 to 1.02, P=0.04). Conclusions: The onset of aortic dissection had something to do with season and month. The incidence of aortic dissection increases with temperature decreases.

[Analysis of the effect of mesial implant position on surrounding bone stress of mandibular edentulous jaw under dynamic loads]

Objective: To evaluate the effect of different placement of mesial implants in edentulous jaws on the stress of the implant and the surrounding bone tissue by three-dimensional (3D)finite element analysis. Methods: Cone-beam CT data of mandibular edentulous patients was transferred into Mimics 17.0 and UG NX8.5 software, and three groups of 3D solid model were established: two mesial implants were implanted in the anterior region of the mandible (bilateral central incisor, lateral incisor, canine), and two distal oblique implant with 30° were implanted in the mandibular second premolar area(5 mm near the mental foramen). Set mandible 3D model with 4 implant by using UG NX8.5 software, produced 3 groups (mandible Ⅰ-Ⅲ). We took dynamic loading on models with help of software Abaqus 6.12, working side posterior teeth loading was set to 150 N and the simulation cycle was 0.875 s. The first stage: 0.000 s to 0.130 s, the lower jaw moves outward (moving toward the side of the work), with no contact between the upper and lower teeth; the second stage: 0.130 s to 0.150 s, mandibular upward, the same tooth tip of the working side were relative, the loading position were the posterior buccal tip, tongue tip; the third stage: 0.150 s to 0.260 s, the buccal slopes of buccal tips of mandibular posterior teeth glide along the lingual slopes of buccal tips of maxillary posterior teeth, the loading force was from the buccal side to the lingual side, the long axis of the tooth was 45°, loaded on the buccal slopes of buccal tips of posterior teeth; the fourth stage: 0.260 s to 0.300 s, the lingual slopes of buccal tips of mandibular posterior teeth glide along the buccal slopes of the tongue tips of maxillary posterior teeth, separate from the tip of the tooth at half the length, the loading force was from the lingual side to the buccal side, the long axis of the tooth was 45°, loaded on the lingual slopes of buccal tips of posterior teeth; the fifth stage: 0.300 s to 0.875 s, at the unloading stage, mandibular posterior teeth were separated from the maxillary teeth and returned to the intercuspal position. The loading position varied according to the mastication cycle. The stress distribution of implant and surrounding bone tissue at different stages of each model were observed. Results: From the early stage to chew occlusal contact to the end of the mastication cycle, three groups of models were displayed: the stress of distal implants was greater than that of mesial implants and the neck stress reached the maximum and gradually decreased to the root tip. The stress of distal implant bone was greater than that of mesial implant bone and the stress of distal bone of distal implant was greater than that of mesial bone of distal implant. All the stress peak showed a gradual increase, and the stress reach the maximum at the fourth stage. In the 3 models, the bone stress around the distal implant of model of the anterior implant located in the lateral incisor region was the lowest. The peak stress of cortical bone of the distal position of implant was 58.7 MPa. The bone stress around the distal implant of model of the anterior implant located in the canine region reached the maximum, and the peak stress of cortical bone of the distal position of implant was 135.6 MPa. Conclusions: When mesial implants of edentulous jaws located in the lateral incisor region, it is good for stress dispersion.

[Application of the descending branch of the lateral circumflex femoral artery in the coronary artery bypass grafting operation]

Objective: To investigate the technical method for harvesting and application of the descending branch of the lateral circumflex femoral artery (DBLCFA) in the coronary artery bypass grafting (CABG) operation. Methods: Between December 2016 and April 2017, 19 patients were arranged to use DBLCFA and got CT angiography (CTA) of pelvic and femoral arteries pre-operative at Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College. Finally, DBLCFA was harvested in 16 patients (including 2 female patients, with a mean age of (47.4±8.5) years) through the anterior thigh incision (13 cases on the left side, 3 cases on the right side). The CABG operations were performed under the cardiopulmonary bypass support (in 10 cases) or under the beating heart condition (in 6 cases), and the DBLCFA conduit was used combining with bilateral internal thoracic artery (in 12 cases), radial artery (in 7 cases) and saphenpous vein (in 3 cases). Results: Due to anatomical variations such as short length and anomalous branch, or due to silent atherosclerosis stenosis of femoral artery, DBLCFA in 3 patients was considered inappropriate for use and was not harvested after CTA examination. In another 16 patients, DBLCFA was safely and quickly harvested and successfully used. On average, 3.4±0.6 anastomosis was built up in CBAG, no adverse effects were exhibited. The length of the harvested DBLCFA was (10.3±1.8) cm, with average lumen diameter of (1.9±0.5) mm. DBLCFA was used as free graft in 15 patients (7 to the first diagonal branch, 6 to the ramus intermedius branch, 1 to the left anterior descending branch and 1 to the second obtuse marginal branch). In 1 patient, the DBLCFA was firstly implanted end-to-side to the internal thoracic artery as a "Y" type composite graft, and then anastomosed to the third obtuse marginal branch. Conclusions: The descending branch of the lateral circumflex femoral artery is an option conduit in CABG. It can be harvested easily and safely. However, pre-operative CTA examination is necessary to exclude the variation and appropriate strategy for graft establishment should be considered during the operation.

[Preliminary application of amide proton transfer imaging signal in acute ischemic stroke]

OBJECTIVE

To apply amide proton transfer magnetic resonance imaging (APT-MRI) technique to acute ischemic stroke, and to discuss clinical values of the APT-MRI main parameter - MTRasym(3.5 ppm).

METHODS

A total of 18 emergency admitted patients, with acute ischemic stroke from Beijing Hospital, were recruited from March to November 2015. Eventually, 18 patients (male 14, female 4, average age 72 years old, age ranged from 52 to 92 years, symptom onset ≤24 hours, 2 patients≤ 6 hours) were included in this study. All patients underwent MR scanning on the brain at 3.0 Tesla. Besides the conventional scans for stroke, the APT sequence (saturation time 0.8 s, saturation power 2 μT) was performed. APT weighted (APTW) images were calculated using magnetization transfer ratio asymmetry at 3.5 ppm with respect to water. MRI signals in APTW, diffusion weighted images (DWI) and fluid attenuated iversion recovery (FLAIR) were visually evaluated. Shapiro-Wilk tests were performed to find out the distribution of MTRasym(3.5 ppm) in the whole sample, infarction regions, and normal appearing white matter (NAWMs), respectively. Detrended normal P-P plots were also used to evaluate its normality. Paired-t test and two-sample t test were applied to compare the mean MTRasym(3.5 ppm) of infarction regions with that of contra lateral NAWMs.

RESULTS

(1) High signal intensity was observed in DWI and FLAIR in all 18 patients. However, signal intensity was somewhat different in APTW. 13 patients were found decreased APT effect, and 5 patients were with equal APT effect in infarction regions. In NAWMs, 14 patients were found equal APT effect, and 4 patients were with decreased APT effect. (2) MTRasym(3.5 ppm)s were proven, with Shapiro-Wilk test, to distribute normally within the whole sample (W=0.964, P=0.288), infarction regions (W=0.962, P=0.645), and NAWMs(W=0.929, P=0.187). However, its normality was not so satisfactory due to greater deviations (absolute value>0.06) of some cases in detrended normal P-P plots. (3) Paired-t test analysis showed that MTRasym(3.5 ppm) in infarction regions (-0.035%±1.020%) was significantly lower than that in NAWMs (0.386%±0.790%) (t=-2.273, P=0.036). However, there was no statistically significant difference between infarction regions and NAWMs when two sample t-test was performed (t=-1.386, P=0.175).

CONCLUSION

MTRasym(3.5 ppm) can be used to evaluate acute ischemic stroke with a broad future scope in clinical.

Optical and magneto-optical anisotropies in large-area two-dimensional Co antidots film

In this work, we investigate the plasmon-induced optical and magneto-optical anisotropies in the large-area square-ordered Co antidots film. It shows that both the outline of reflectivity spectrum and Kerr spectrum are significantly modified by surface plasmon polarition (SPP) resonances. Moreover, the magnitude of Kerr angle reaches to about 10 minutes at the azimuthal angle 45°, which is over 3 times of that of pure Co film. These phenomena are attributed to the SPP resonances with different diffraction orders of reciprocal lattice vectors.

Inhibition of the acquisition of conditioned place aversion by dopaminergic lesions of the central nucleus of the amygdala in morphine-treated rats

The negative affective state of opiate abstinence plays an important role in craving and relapse to compulsive drug use. The dopamine system participates in the reward effects of opiate use and the aversive effect of opiate abstinence. The amygdala is an essential neural substrate for associative learning of emotion. To establish a model of conditioned place aversion (CPA) in morphine-treated rats, we used different visual and tactual cues as conditioned stimuli (CS) within a conditioning apparatus. An injection of naloxone served as the unconditioned stimulus (US). The 6-hydroxydopamine (6-OHDA) lesion technique was used to investigate the effects of the dopaminergic system of the central nucleus of the amygdala (CeA) on naloxone-induced CPA. Rats were rendered physically dependent via administration of increasing doses of morphine delivered via intraperitoneal injection. Doses increased by 20 % each day for 14 days, starting from an initial dose of 6 mg/kg. All rats also received a low dose of naloxone (0.1 mg/kg) by injection 4 hours after morphine treatment on days 11 and 13 to induce CPA in a biased two-compartment conditioned place apparatus. Morphine-dependent rats with sham lesions were found to develop significant CPA after naloxone treatment. Bilateral 6-OHDA lesions of the CeA impaired the acquisition of CPA but had no effect on locomotor activity. These results suggest that the dopaminergic system of the CeA plays an important role in the negative affective state of opiate abstinence.

A modified cannulating technique for the BVS5000

The aim of this study was to report on a modified cannulating method for the BVS5000 left ventricular assist device. From April 2005 to April 2006, a BVS5000 device was implanted using a modified cannulating method in 7 postcardiotomy male patients after coronary artery bypass grafting for left ventricular support. The inflow cannula was inserted into the left atrial artery through a segment of bovine jugular vein and the arterial cannula into the femoral artery. Five patients were successfully weaned from the BVS5000 after recovery of heart function and were discharged from hospital. The BVS5000 was explanted using a minimally invasive technique. The weaning procedure was completed bedside in the intensive care unit under local anesthesia; resternotomy was not necessary. The modified technique is a simpler, safer and more minimally invasive method for selected patients supported by the BVS5000.

Novelty-seeking behavior and stress-induced locomotion in rats of juvenile period differentially related to morphine place conditioning in their adulthood

The relationship between motor responses in a novel environment and susceptibility to place conditioning effect of psychostimulants has been reported in adult rats. However, it is in question whether this correlation could be generalized to motor activity in rats of juvenile period and place conditioning effect in their adulthood for narcotic morphine. In the present study, we tested locomotor activity in an arena open-field and the subsequent novelty-seeking behavior after adaptation process in juvenile rats (P42) and morphine (2 mg/kg) place conditioning effect 56 days later in the same rats' adulthood (P98). Our results showed that rats with high response to novelty (HRN) spent more prolonged duration in the drug-paired compartment in the place conditioning test compared with their low response counterparts (LRN), with the latter group no salient change on this measure. Moreover, rats with high response to the open-field test (HRS) expressed equally elevated duration in drug-paired side relative to their low response counterparts (LRS). The present research demonstrated that novelty-seeking behavior and locomotor activity in the open-field in rats of juvenile period differentially related to morphine place conditioning in their adulthood, with slow acquisition of morphine place conditioning effect in LRN animals.