Isolation and characterization of cDNAs corresponding to an additional member of the human histone deacetylase gene family

Several human cDNAs encoding a histone deacetylase protein, HDAC3, have been isolated. Analysis of the predicted amino acid sequence of HDAC3 revealed an open reading frame of 428 amino acids with a predicted molecular mass of 49 kDa. The HDAC3 protein is 50% identical in DNA sequence and 53% identical in protein sequence compared with the previously cloned human HDAC1. Comparison of the HDAC3 sequence with human HDAC2 also yielded similar results, with 51% identity in DNA sequence and 52% identity in protein sequence. The expressed HDAC3 protein is functionally active because it possesses histone deacetylase activity, represses transcription when tethered to a promoter, and binds transcription factor YY1. Similar to HDAC1 and HDAC2, HDAC3 is ubiquitously expressed in many different cell types.

Regulation of transcription factor YY1 by acetylation and deacetylation

YY1 is a sequence-specific DNA-binding transcription factor that has many important biological roles. It activates or represses many genes during cell growth and differentiation and is also required for the normal development of mammalian embryos. Previous studies have established that YY1 interacts with histone acetyltransferases p300 and CREB-binding protein (CBP) and histone deacetylase 1 (HDAC1), HDAC2, and HDAC3. Here, we present evidence that the activity of YY1 is regulated through acetylation by p300 and PCAF and through deacetylation by HDACs. YY1 was acetylated in two regions: both p300 and PCAF acetylated the central glycine-lysine-rich domain of residues 170 to 200, and PCAF also acetylated YY1 at the C-terminal DNA-binding zinc finger domain. Acetylation of the central region was required for the full transcriptional repressor activity of YY1 and targeted YY1 for active deacetylation by HDACs. However, the C-terminal region of YY1 could not be deacetylated. Rather, the acetylated C-terminal region interacted with HDACs, which resulted in stable HDAC activity associated with the YY1 protein. Finally, acetylation of the C-terminal zinc finger domain decreased the DNA-binding activity of YY1. Our findings suggest that in the natural context, YY1 activity is regulated through intricate mechanisms involving negative feedback loops, histone deacetylation, and recognition of the cognate DNA sequence affected by acetylation and deacetylation of the YY1 protein.

The hepatitis B virus X-associated protein, XAP3, is a protein kinase C-binding protein

The hepatitis B virus X protein induces transcriptional activation of a wide variety of viral and cellular genes. In addition to its ability to interact directly with many nuclear transcription factors, several reports indicate that the X protein stimulates different cytoplasmic kinase signal cascades. Using the yeast two-hybrid screen, we have isolated a clone designated X-associated protein 3 (XAP3) that encodes a human homolog of the rat protein kinase C-binding protein. One of the activation domains of X (amino acids 90-122) is required for binding to XAP3, while the NH2-terminal part of XAP3 is necessary for binding to X. Both X and XAP3 bound specifically to the eta PKC isoenzyme synthesized in rabbit reticulocyte lysates. Overexpression of XAP3 enhanced X transactivation activity. These results support earlier findings that one of the mechanisms of transactivation by X is through involvement with the cellular protein kinase C pathway.

Cloning, chromosomal localization and promoter analysis of the human transcription factor YY1

Yin Yang 1 (YY1) is a protein that activates and represses transcription of a large number of cellular and viral genes. In addition, studies suggest that YY1 may play an important role in development and differentiation. Here, we report the isolation and analysis of a YY1 genomic clone from a lambda human liver library. Fluorescence in situ hybridization with the YY1 clone has localized the YY1 gene to chromosome 14 band q32. A major YY1 gene transcription initiation site has been mapped to 478 bp upstream of the ATG translation start site. The proximal promoter contains multiple Sp1 transcription factor binding sites but lacks a consensus TATA or CCAAT box. Transient transfections and detailed deletion analyses localized the promoter to no more than 277 bp upstream from the major transcription start site. Finally, we have found that overexpression of the adenovirus E1A protein represses expression of a reporter gene directed by the YY1 promoter.

Gastrin, somatostatin, G and D cells of gastric ulcer in rats

AIM: To investigate the relationship among gastrin, somatostatin, G and D cells in gastric ulcer and in its healing process in rats.

METHODS: Fourty-nine Wistar rats were divided into 7 groups. The gastric ulcer model was induced by acetic acid successfully. The gastrin and the somatostatin in rat plasma, gastric fluid and antral tissue were measured by radioimmunoassay (RIA). G and D cells in antral mucosa were analyzed with polyclonal antibody of gastrin and somatostatin by immunohistochemical method and Quantimet 500 image analysis system.

RESULTS: In gastric ulcer, the level of gastrin in plasma, gastric fluid, and antral tissue increased, that of somatostatin declined, and the disorder gradually recovered to the normal level in the healing process. Immunohistochemical technique of G and D cells in antral mucosa demonstrated that the number of G cells increased and that of D cells decreased, both areas of G and D cells declined, the ratio of number and area of G/D increased in gastric ulcer, and the disorder gradually recovered in the healing process.

CONCLUSION: In gastric ulcer, the increased gastrin secreted by G cells, the declined somatostatin secreted by D cells, and the disordered G/D cell ratio can lead to gastrointestinal dysfunction.

Overexpression of cyclin E in Mongolian gerbil with Helicobacter pylori- induced gastric precancerosis

AIM: To explore dysregulation of cyclin E in malignancies, and to further investigate the role of cyclin E in Helicobacter pylori (H. pylori)-induced gastric precancerosis.

METHODS: Four-week-old specific pathogen-free male Mongolian gerbils were employed in the study. 0.5 mL 1 × 10⁸ cfu·L^-1 suspension of H. pylori NTCC11637 in Brucella broth was inoculated orally into each of 20 Mongolian gerbils, and a further 20 gerbils were inoculated with Brucella broth as controls. 10 of the infected gerbils and 10 of the non-infected control gerbils were sacrificed at 25, 45 wk after infection. The expression of cyclin E was analyzed by RT-PCR and immunohistochemical studies with monoclonal antibody to cyclin E in Mongolian gerbil of H. pylori-induced gastric precancerosis.

RESULTS: H. pylori was constantly detected in all infected animals throughout the study. At 25 wk after infection of H. pylori. ulcers were observed in the antral and body of stomach (n = 6). Histological examination showed that all animals developed severe inflammation and multifocal lymphoid follicles appeared in the lamina propria and submucosa of gastric antrum. At 45 wk after infection of H. pylori, severe atrophic gastritis (n = 10). intestinal metaplasia (n = 8) and dysplasia (n = 6) could be observed. Cyclin E mRNA levels were significantly more at 25 wk after infection of H. pylori (1.27 ± 0.26), and at 45 wk after infection of H. pylori ( 1.82 ± 0.39) than control-animals (0.59 ± 0.20,P < 0.01); cyclin E mRNA levels were evaluated by 2.2-fold at 25 wk (P < 0.01) and 3.1-fold at 45 wk (P < 0.01) precancerosis induced by H. pylori, when compared with control gastric epithelium of Mongolian gerbil. Immunohistochemical staining revealed exclusive nuclear staining of cyclin E. Furthermore, there was a sequential increase in cyclin E positive cells from normal epithelium to precancerosis.

CONCLUSION: Overexpression of cyclin E occurs relatively early in gastric tumorigenesis in this model.

Association between the expression of mast cell chymase and intraperitoneal adhesion formation in mice

BACKGROUND

Adhesion formation is a major source of postoperative morbidity and mortality. Mast cells and their major protease, chymase, have been shown to participate in the healing process as well as in tissue remodeling. We aimed to identify the role of mast cells in intraperitoneal adhesion formation and to assess whether there is an association between the expression of mast cell chymase and adhesion formation.

MATERIALS AND METHODS

Both mast cell-deficient W/W(V) mice and congenic +/+ mice received a standardized lesion produced by cecal scraping and the application of 95% ethanol. Adhesions were assessed blindly 1 week later using a standardized scale. In addition, histamine content, mast cell numbers, and chymase activity in cecum as well as at the healing sites were evaluated before and 7 days after surgical injury.

RESULTS

A significant reduction in adhesion formation was seen in mast cell-deficient W/W(V) mice (P < 0.05). In the normal cecum, histamine content did not significantly differ between W/W(V) and +/+ mice. Chymase activity in cecum was detected in control +/+ mice, but not in W/W(V) mice. Mast cell numbers and chymase activity levels at the healing sites of +/+ mice were significantly increased 7 days after surgery.

CONCLUSIONS

Our results indicate that mast cells contribute to intraperitoneal adhesion formation in mice, and suggest that chymase originating from mast cells is important in the development of adhesions.

Cloning and characterization of the mouse histone deacetylase-2 gene

Histone deacetylase-2 (HDAC2) is a component of a complex that mediates transcriptional repression in mammalian cells. A mouse HDAC2 cDNA was used to identify several recombinant clones containing the entire mouse HDAC2 gene. The mouse HDAC2 gene spans over 36 kilobase pairs and is composed of 14 exons (ranging from 58 to 362 nucleotides in length) and 13 introns (ranging from 75 base pairs to 19 kilobase pairs in length). Primer extension analysis with total RNA from NIH3T3 cells revealed a major transcriptional start site at 221 base pairs 5' of the ATG translational start codon. Upstream of the transcriptional start site, no canonical TATA box was found, but binding sites for several known transcription factors were identified. Transient transfection studies with 5' deletion mutants localized the promoter to no more than 76 base pairs upstream from the major transcriptional start site. Fluorescence in situ hybridization mapped mouse HDAC2 to chromosomal location 10B1, which is in close proximity to the growth factor-inducible gene fisp-12. Information concerning the genomic organization and promoter of HDAC2 will be useful in studies of the regulation of histone deacetylase activities, which in turn are important in studies of the regulation of transcriptional repression in mammalian cells.

THE DECADE OF THE RABiT (2005-15)

The RABiT (Rapid Automated Biodosimetry Tool) is a dedicated Robotic platform for the automation of cytogenetics-based biodosimetry assays. The RABiT was developed to fulfill the critical requirement for triage following a mass radiological or nuclear event. Starting from well-characterized and accepted assays we developed a custom robotic platform to automate them. We present here a brief historical overview of the RABiT program at Columbia University from its inception in 2005 until the RABiT was dismantled at the end of 2015. The main focus of this paper is to demonstrate how the biological assays drove development of the custom robotic systems and in turn new advances in commercial robotic platforms inspired small modifications in the assays to allow replacing customized robotics with 'off the shelf' systems. Currently, a second-generation, RABiT II, system at Columbia University, consisting of a PerkinElmer cell::explorer, was programmed to perform the RABiT assays and is undergoing testing and optimization studies.

Transactivation by expression of the hepatitis B virus X protein with an inducible system

We describe here the conditional expression of the hepatitis B virus X protein using the inducible system controlled by a tet-responsive promoter. Induction of the X protein in Rat-2 fibroblasts activated transcription from a heterologous gene promoter and stimulated the DNA-binding activity of NFkB. The ability to produce this biologically active X protein in a stable cell line will accelerate the elucidation of the function and mechanisms of X and eventually help us understand the role of X in natural viral infection and carcinogenesis.

Diagnostic classification of endosonography for differentiating colorectal ulcerative diseases: A new statistical method

AIM

To establish a classification method for differential diagnosis of colorectal ulcerative diseases, especially Crohn’s disease (CD), primary intestinal lymphoma (PIL) and intestinal tuberculosis (ITB).

METHODS

We searched the in-patient medical record database for confirmed cases of CD, PIL and ITB from 2008 to 2015 at our center, collected data on endoscopic ultrasound (EUS) from randomly-chosen patients who formed the training set, conducted univariate logistic regression analysis to summarize EUS features of CD, PIL and ITB, and created a diagnostic classification method. All cases found to have colorectal ulcers using EUS were obtained from the endoscopy database and formed the test set. We then removed the cases which were easily diagnosed, and the remaining cases formed the perplexing test set. We re-diagnosed the cases in the three sets using the classification method, determined EUS diagnostic accuracies, and adjusted the classification accordingly. Finally, the re-diagnosing and accuracy-calculating steps were repeated.

RESULTS

In total, 272 CD, 60 PIL and 39 ITB cases were diagnosed from 2008 to 2015 based on the in-patient database, and 200 CD, 30 PIL and 20 ITB cases were randomly chosen to form the training set. The EUS features were summarized as follows: CD: Thickened submucosa with a slightly high echo level and visible layer; PIL: Absent layer and diffuse hypoechoic mass; and ITB: Thickened mucosa with a high or slightly high echo level and visible layer. The test set consisted of 77 CD, 30 PIL, 23 ITB and 140 cases of other diseases obtained from the endoscopy database. Seventy-four cases were excluded to form the perplexing test set. After adjustment of the classification, EUS diagnostic accuracies for CD, PIL and ITB were 83.6% (209/250), 97.2% (243/250) and 85.6% (214/250) in the training set, were 89.3% (241/270), 97.8% (264/270) and 84.1% (227/270) in the test set, and were 86.7% (170/196), 98.0% (192/196) and 85.2% (167/196) in the perplexing set, respectively.

CONCLUSION

The EUS features of CD, PIL and ITB are different. The diagnostic classification method is reliable in the differential diagnosis of colorectal ulcerative diseases.

High-Flux Neutron Generator Based on Laser-Driven Collisionless Shock Acceleration

A novel compact high-flux neutron generator with a pitcher-catcher configuration based on laser-driven collisionless shock acceleration (CSA) is proposed and experimentally verified. Different from those that previously relied on target normal sheath acceleration (TNSA), CSA in nature favors not only acceleration of deuterons (instead of hydrogen contaminants) but also increasing of the number of deuterons in the high-energy range, therefore having great advantages for production of high-flux neutron source. The proof-of-principle experiment has observed a typical CSA plateau feature from 2 to 6 MeV in deuteron energy spectrum and measured a forward neutron flux with yield 6.6×10^{7}  n/sr from the LiF catcher target, an order of magnitude higher than the compared TNSA case, where the laser intensity is 10^{19}  W/cm^{2}. Self-consistent simulations have reproduced the experimental results and predicted that a high-flux forward neutron source with yield up to 5×10^{10}  n/sr can be obtained when laser intensity increases to 10^{21}  W/cm^{2} under the same laser energy.

[Application of a light-weighted convolutional neural network for automatic recognition of coal workers' pneumoconiosis in the early stage]

Objective: To construct and verify a light-weighted convolutional neural network (CNN), and explore its application value for screening the early stage (subcategory 0/1 and stage Ⅰ of pneumoconiosis) of coal workers' pneumoconiosis (CWP) from digital chest radiography (DR) . Methods: A total of 1225 DR images of coal workers who were examined at an Occupational Disease Prevention and Control Institute in Anhui Province from October 2018 to March 2021 were retrospectively collected. All DR images were collectively diagnosed by 3 radiologists with diagnostic qualifications and gave diagnostic results. There were 692 DR images with small opacity profusion 0/- or 0/0 and 533 DR images with small opacity profusion 0/1 to stage Ⅲ of pneumoconiosis. The original chest radiographs were preprocessed differently to generate four datasets, namely 16-bit grayscale original image set (Origin16), 8-bit grayscale original image set (Origin 8), 16-bit grayscale histogram equalized image set (HE16) and 8-bit grayscale histogram equalized image set (HE8). The light-weighted CNN, ShuffleNet, was applied to train the generated prediction model on the four datasets separately. The performance of the four models for pneumoconiosis prediction was evaluated on a test set containing 130 DR images using measures such as the receiver operating characteristic (ROC) curve, accuracy, sensitivity, specificity, and Youden index. The Kappa consistency test was used to compare the agreement between the model predictions and the physician diagnosed pneumoconiosis results. Results: Origin16 model achieved the highest ROC area under the curve (AUC=0.958), accuracy (92.3%), specificity (92.9%), and Youden index (0.8452) for predicting pneumoconiosis, with a sensitivity of 91.7%. And the highest consistency between identification and physician diagnosis was observed for Origin16 model (Kappa value was 0.845, 95%CI: 0.753-0.937, P<0.001). HE16 model had the highest sensitivity (98.3%) . Conclusion: The light-weighted CNN ShuffleNet model can efficiently identify the early stages of CWP, and its application in the early screening of CWP can effectively improve physicians' work efficiency.

[A study of the relationship between electromyographic activity of the masticatory muscles and the variations of the occlusal vertical dimension for edentulous subjects]

The study was performed in fifteen edentulous subjects with the EMG activity were recorded at the varying occlusal vertical dimension maintaining constant bite force value of 4kg.The results showed that maintaining constant bite force the amplitudes of EMG activity of the anterior temporal and masseter muscles are decreased with increasing the occlusal vertical dimension and correlation relation between them,that there is a stable region about 1.0mm for the anterior temporal muscle and about 1.5mm for the masseter muscle during the changes in electrical activity.It is represent that there is a physiological region of the occlusal vertical dimension for edentulous patient.

[Expert consensus on visualized tele-round and quality control management based on the improvement of clinical practice ability]

Turning to critical illness is a common stage of various diseases and injuries before death. Patients usually have complex health conditions, while the treatment process involves a wide range of content, along with high requirements for doctor's professionalism and multi-specialty teamwork, as well as a great demand for time-sensitive treatments. However, this is not matched with critical care professionals and the current state of medical care in China. Telemedicine, which shortens the distance of medical professionals and the gap of disease diagnosis and treatments in various regions through electronic information, can effectively solve the current problem. Therefore, there is an urgent need to develop a standardized, high-quality visualization telemedicine round system .Therefore, experts have been organized to search domestic and foreign literature on telemedicine round for critically ill patients and to form this consensus based on clinical experiences so as to further improve the level of critical care treatments in regions.

Distribution characteristics of ApoE gene polymorphism in the Tibetan population of Qinghai

Objective:

To understand the distribution characteristics of the relative frequencies of apolipoprotein E (APOE) alleles in Tibetans of Qinghai province, to provide a basis for subsequent research.

Method:

Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to determine the APOE genotypes and analyze the distribution characteristics in 96 indigenous Tibetans randomly selected from the Medical Examination Center of Qinghai Provincial People’s Hospital, and the results of this study were compared with those of other ethnic groups in China.

Results:

The frequencies of E2, E3, and E4 alleles in the 96 subjects were 1.563%, 89.062%, and 9.375%, respectively, and the genotype frequencies were E2/E2 (0%), E2/E3 (3.125%), E2/E4 (0%), E3/E3 (78.125%), E3/E4 (18.750%), and E4/E4 (0%), respectively. The frequency distribution of the ε2 allele in the Tibetan population was lower than that of the Northern Han, Southern Hakka, Hui, Mongolian, and Dai populations of China. The frequency distribution of the ε4 allele in the Tibetan population was of no significant difference compared with that of the Northern Han, Southern Hakka, Hui, and Mongolian populations, but was higher than that of the Dai population. The frequency distribution of the ε3 allele in the Tibetan population was of no significant difference compared with that of the Northern Han, Mongolian, and Dai populations, but higher than that of the Southern Hakka and Mongolian populations.

Conclusion:

There are ethnic differences in the frequency distribution of the three common alleles of APOE.

[Neovascularization aggravated hepatic fibrosis in combined hypoxia NASH rat model]

Objective: To optimize the construction of combined hypoxia NASH rat model on the basis of preliminary work, and to explore the role of neovascularization in the process of hepatic fibrosis. Methods: 32 rats were divided randomly to four groups that were null control group(A group ), hypoxia group(B group), high fat diet group(C group ) and high fat diet plus hypoxia group (D group ),treated with null , Intraperitoneal injection of NaNO(2), high fat diet and high fat diet plus Intraperitoneal injection of NaNO(2) respectively. Every group was observed for 16 weeks, B and D group was treated with Intraperitoneal injection of NaNO(2) 20 mg/kg.d at the laster 8 weeks. Liver histology NASH activity score(NAS) and Fibro score(FibroS), biochemical index were detected in this combined hypoxia NASH rat model(D group), meanwhile the changes of HIF1α, inflammatory factor and neovascularization were measured by ELISA, realtime PCR and immunohistochemistry. Results: Liver tissue NAS > 4 was seen in C and D group. D group showed NASH characteristics, including significantly steatosis at liver acinar 3 area(mostly a microvesicular type fat droplets mixed with macrovesicular type), hepatocyte balloon degeneration, obvious lobular inflammation, while fibrosis score increased significantly, including visible hepatic sinusoid fibrosis, fibrosis around portal vein, and bridging fibrosis in a considerable portion of the rats. Compared with C group, biochemical indicators of aspartate aminotransferase (AST), HIF1α, neovascularization-related VEGFA, VEGFR2 mRNA level increased obviously and the expression of immunohistochemistry VEGFR2, CD34 enhanced markedly in D group(p < 0.05). Conclusion: A combined hypoxia NASH rat model can be established throught feeding 16 weeks' high-fat diet then intraperitoneal injection of NaNO(2) 20 mg / kg.d at the laster 8 weeks, meanwhile chronic hypoxia can accelerate this combined hypoxia NASH model liver fibrosis process. In this process neovascularization promoted the formation of hepatic fibrosis in this model.

[Effect of Helicobacter pylori infection on gastric mucosal cell proliferation in Mongolian gerbils]

OBJECTIVE

To explore the mechanism that Helicobacter pylori (H. pylori) infection can induce adenocarcinoma in Mongolian gerbil model with long-term H. pylori infection.

METHODS

Mongolian gerbil model with long-term H. pylori infection was established by inoculation H. pylori NCTC 11637 strain, and immunohistochemical straining and in situ hybridization were employed to observe changes in gastric mucosal cell proliferation due to H. pylori infection.

RESULTS

Mongolian gerbil model with long-term H. pylori infection was successfully established. Immunohistochemical staining of 5'-bromodeoxyuridine (BrdU) and proliferating cell nuclei antigen (PCNA) showed that H. pylori infection induced the increase in gastric mucosal cell proliferation (P<0.05), and in situ hybridization of epidermal growth factor (EGF) and epidermal growth factor receptor (EGFR) revealed elevated expressions of EGF mRNA and EGFR mRNA with time passage after H. pylori infection (P<0.05).

CONCLUSION

H. pylori inoculation can induce abnormality in gastric mucosal cell proliferation, which is instrumental for the progression from chronic gastritis to glandular atrophy, intestinal metaplasis and ultimately to atypical hyperplasia. The abnormal expressions of EGF and EGFR may be the key element for abnormality of gastric mucosal cell proliferation.

[Influence of the blight of Morinda officinalis How on microscopic structure and constituents of the host]

The results showed that microscopic structure in biennial roots, the contents of B and Mn in nutritive organ and beta-sitosterol content in roots, stems of Morinda officinalis were affected markedly. The total sugar content in the roots and aerial stems was decreased by 5.42%-15.29%.