A Non-Canonical Role for p27\u3csup\u3eKip1\u3c/sup\u3e in Restricting Proliferation of Corneal Endothelial Cells During Development

This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The cell cycle regulator p27Kip1 is a critical factor controlling cell number in many lineages. While its anti-proliferative effects are well-established, the extent to which this is a result of its function as a cyclin-dependent kinase (CDK) inhibitor or through other known molecular interactions is not clear. To genetically dissect its role in the developing corneal endothelium, we examined mice harboring two loss-of-function alleles, a null allele (p27−) that abrogates all protein function and a knockin allele (p27CK−) that targets only its interaction with cyclins and CDKs. Whole-animal mutants, in which all cells are either homozygous knockout or knockin, exhibit identical proliferative increases (~0.6-fold) compared with wild-type tissues. On the other hand, use of mosaic analysis with double markers (MADM) to produce infrequently-occurring clones of wild-type and mutant cells within the same tissue environment uncovers a roughly three- and six-fold expansion of individual p27CK−/CK− and p27−/− cells, respectively. Mosaicism also reveals distinct migration phenotypes, with p27−/− cells being highly restricted to their site of production and p27CK−/CK− cells more widely scattered within the endothelium. Using a density-based clustering algorithm to quantify dispersal of MADM-generated clones, a four-fold difference in aggregation is seen between the two types of mutant cells. Overall, our analysis reveals that, in developing mouse corneal endothelium, p27 regulates cell number by acting cell autonomously, both through its interactions with cyclins and CDKs and through a cyclin-CDK-independent mechanism(s). Combined with its parallel influence on cell motility, it constitutes a potent multi-functional effector mechanism with major impact on tissue organization

Survey of hepatitis B knowledge and stigma among chronically infected patients and uninfected persons in Beijing, China

Background & AimsHepatitis B virus (HBV) infection carries substantial stigma in China. We surveyed HBV knowledge and stigma among chronic hepatitis B (CHB) patients and persons without HBV infection in Beijing, China.MethodsFour hundred and thirty five CHB patients and 801 controls at Peking University People’s Hospital were surveyed.ResultsChronic hepatitis B patients were older (mean 46 vs. 39 years) and more often men (71 vs. 48%) than controls. Mean knowledge score was 11.9/15 for CHB and 9.3/15 for control patients (P < 0.001). Average stigma score was 22.1/39 for CHB and 19.2/30 for control patients. Controls expressed discomfort with close contact (45%) or sharing meals with CHB patients (39%) and believed CHB patients should not be allowed to work in restaurants (58%) or childcare (44%). Chronic hepatitis B patients felt that they were undesirable as spouses (33 vs. 17%) and brought trouble to their families (58 vs. 34%) more often than controls. Despite legal prohibitions, 40% of CHB patients were required to undergo pre‐employment HBV testing, and 29% of these individuals thought that they lost job opportunities because of their disease status. 16% of CHB patients regretted disclosing their HBV status and disclosure was inversely associated with stigma. Higher stigma was associated with older age, lower education and lower knowledge score among controls; and with lower education, younger age, having undergone pre‐employment HBV testing and regret disclosing their HBV status among CHB patients.ConclusionDespite high prevalence of CHB in China, our study shows knowledge is limited and there is significant societal and internalized stigma associated with HBV infection.See Editorial on Page 1582Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134440/1/liv13168_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134440/2/liv13168.pd

A Comparative Study of Patients’ Attitudes Toward Clinical Research in the United States and Urban and Rural China

As the number of clinical trials conducted in China increases, understanding Chinese attitudes toward clinical research is critical for designing effective and ethical studies. Two survey studies were conducted in 2012 and 2013 to compare patient attitudes toward clinical research and factors affecting research participation in the United States and urban and rural China. We surveyed 525 patients in 2012 (186 US, 186 urban, 153 rural China) and 690 patients in 2013 (412 US, 206 urban, 72 rural China). US patients were more likely to have no concerns regarding research participation than Chinese patients. Most common concerns of US patients were safety, privacy and confidentiality, and time required. Safety was a top concern for many Chinese. Chinese patients, particularly rural Chinese, were more concerned about the likelihood of self‐benefit, and receiving free medical care and financial incentive had greater influence on their participation. Being informed of the freedom to choose whether to participate or to leave a study was less important to Chinese patients. Our study provides important insights into Chinese patients' attitudes toward clinical research and the need to educate them about their rights. These findings help in designing cross‐cultural clinical studies that maximize enrollment while upholding Western ethical standards.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111170/1/cts12254.pd

Characteristic gene expression in the liver monocyte-macrophage-DC system is associated with the progression of fibrosis in NASH

BackgroundThe monocyte-macrophage-dendritic cell (DC) (MMD) system exerts crucial functions that may modulate fibrogenesis in nonalcoholic steatohepatitis (NASH). In this study, we explored the cell characteristics, distribution and developmental trajectory of the liver MMD system in NASH mice with fibrosis and clarified characteristic genes of the MMD system involved in liver fibrosis progression in NASH mice and patients.MethodsSingle cells in liver tissue samples from NASH and normal mice were quantified using single-cell RNA sequencing (scRNA-seq) analysis. Differentially expressed genes (DEGs) in the MMD system by pseudotime analysis were validated by tyramide signal amplification (TSA)-immunohistochemical staining (IHC) and analyzed by second harmonic generation (SHG)/two-photon excitation fluorescence (TPEF).ResultsCompared with control mice, there were increased numbers of monocytes, Kupffer cells, and DCs in two NASH mouse models. From the transcriptional profiles of these single cells, we identified 8 monocyte subsets (Mono1-Mono8) with different molecular and functional properties. Furthermore, the pseudotime analysis showed that Mono5 and Mono6 were at the beginning of the trajectory path, whereas Mono2, Mono4, Kupffer cells and DCs were at a terminal state. Genes related to liver collagen production were at the late stage of this trajectory path. DEGs analysis revealed that the genes Fmnl1 and Myh9 in the MMD system were gradually upregulated during the trajectory. By TSA-IHC, the Fmnl1 and Myh9 expression levels were increased and associated with collagen production and fibrosis stage in NASH mice and patients.ConclusionsOur transcriptome data provide a novel landscape of the MMD system that is involved in advanced NASH disease status. Fmnl1 and Myh9 expression in the MMD system was associated with the progression of NASH fibrosis

DCs Pulsed with Novel HLA-A2-Restricted CTL Epitopes against Hepatitis C Virus Induced a Broadly Reactive Anti-HCV-Specific T Lymphocyte Response

OBJECTIVE: To determine the capacity of dendritic cells (DCs) loaded with single or multiple-peptide mixtures of novel hepatitis C virus (HCV) epitopes to stimulate HCV-specific cytotoxic T lymphocyte (CTL) effector functions. METHODS: A bioinformatics approach was used to predict HLA-A2-restricted HCV-specific CTL epitopes, and the predicted peptides identified from this screen were synthesized. Subsequent IFN-γ ELISPOT analysis detected the stimulating function of these peptides in peripheral blood mononuclear cells (PBMCs) from both chronic and self-limited HCV infected subjects (subjects exhibiting spontaneous HCV clearance). Mature DCs, derived in vitro from CD14(+) monocytes harvested from the study subjects by incubation with appropriate cytokine cocktails, were loaded with novel peptide or epitope peptide mixtures and co-cultured with autologous T lymphocytes. Granzyme B (GrB) and IFN-γ ELISPOT analysis was used to test for epitope-specific CTL responses. T-cell-derived cytokines contained in the co-cultured supernatant were detected by flow cytometry. RESULTS: We identified 7 novel HLA-A2-restricted HCV-specific CTL epitopes that increased the frequency of IFN-γ-producing T cells compared to other epitopes, as assayed by measuring spot forming cells (SFCs). Two epitopes had the strongest stimulating capability in the self-limited subjects, one found in the E2 and one in the NS2 region of HCV; five epitopes had a strong stimulating capacity in both chronic and self-limited HCV infection, but were stronger in the self-limited subjects. They were distributed in E2, NS2, NS3, NS4, and NS5 regions of HCV, respectively. We also found that mDCs loaded with novel peptide mixtures could significantly increase GrB and IFN-γ SFCs as compared to single peptides, especially in chronic HCV infection subjects. Additionally, we found that DCs pulsed with multiple epitope peptide mixtures induced a Th1-biased immune response. CONCLUSIONS: Seven novel and strongly stimulating HLA-A2-restricted HCV-specific CTL epitopes were identified. Furthermore, DCs loaded with multiple-epitope peptide mixtures induced epitope-specific CTLs responses

Related immune manifestations in patients with chronic hepatitis B virus and chronic hepatitis C virus infection

Patients with chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infection are frequently complicated by autoimmune disorders, which is commonly seen in patients with hepatitis C. This article introduces the mechanism of immune disorders in patients with chronic hepatitis C, the proportion of patients with non-organ specific autoantibody, and the clinical manifestations, diagnosis, and treatment of related immune diseases, such as mixed cryoglobulinemia, glomerulonephritis, Sjogren's syndrome, thyroid disease, and type 2 diabetes, as well as the mechanism of immune disorders, related immune manifestations, and effect of antiviral therapy in patients with chronic hepatitis B. Antiviral therapy for chronic hepatitis B and C can alleviate related immune diseases, but interferon therapy is not appropriate. Therefore, the patients with hepatitis B should be treated with nucleos(t)ide analogues, while those with hepatitis C should be treated with direct-acting antiviral agents

Revisiting Spatiotemporal Changes in Global Urban Expansion during 1995 to 2015

This study used global land-use data interpreted from remote sensing images to quantitatively analyze the spatial and temporal changes in global urban expansion over the past 20 years, as well as the source, rate of expansion, and urban growth patterns of newly added urban land (NAUL) around the world. Some main conclusions included the following. (1) Globally, NAUL was mainly derived from agriculture, grassland, and forest. These three types of land use contributed 68.93%, 10.10%, and 9.76%, respectively, to the land sources for NAUL. (2) Eight countries/regions (CRs)—India, Pakistan, Nigeria, Bangladesh, Philippines, Ethiopia, Egypt, and Vietnam—had significant potential for future urban growth and were designated as the “Emerging Urban Growth G8.” Also, Africa will continue to lead global urbanization after Asia. (3) Global urban expansion was still in a typical stage of edge expansion. Urban expansion in Oceania was the most aggregated, whereas in Asia, it was the most diffuse. (4) Apart from African CRs, the urban expansion rate in most CRs was higher than the population urbanization rate, so urbanization does not pose a significant threat to global food security. In addition, for CR with NAUL>1,000 km2, the level of economic development had a positive effect compact urban development. This study mapped large-scale urban expansion using unified data, a unified definition of urban boundaries, and over a unified time span

Effect of Compactness of Urban Growth on Regional Landscape Ecological Security

With rapid urbanization destroying the ecological environment, scholars have focused on ways to coordinate harmonious development using urban spatial layouts and landscape ecological security. To explore landscape ecological security (the landscape elements, spatial positions and connections that are of key significance to the health and safety of ecological processes) from the perspective of urban form evolution pattern will help to open a new perspective of urban management research, and become the basic work of urban space policy and the implementation of the beautiful China strategy. Based on urban growth and land use data from 356 cities in China, this study applied a geographically weighted regression (GWR) model to quantify the impact of China’s urban growth pattern on landscape ecological security at the spatial level. The research results show that: (1) To some extent, the infilling growth pattern has a certain effect on the enhancement of regional landscape ecological security; (2) In the three control variables (DEM, Population density and GDP), the following conclusions are drawn: regional landscape planning should reasonably allocate landscape resources according to the local topographic features to obtain a higher landscape ecological security; The increase of population density leads to the fragmentation and diversity of the landscape in some regions, which makes the landscape ecological security weak; more economically developed areas have stronger landscape ecological security. This paper highlights the importance of urban growth patterns to landscape ecological security. In addition, considering the different urban evolution trajectories in developed and developing countries, this study proposes targeted development recommendations, providing a reference for urban managers to formulate reasonable development policies and to realize sustainable development with the goal of landscape safety management and control