CD4+ T cells, human cytomegalovirus and end-stage renal disease

Ecosystem Services Research Trends: A Bibliometric Analysis from 2000–2020

The study of ecosystem services (ES) is becoming increasingly popular, as it plays an important role in human wellbeing, economic growth, and livelihoods. The primary goal of this research is to investigate the global trend in ES research using a rigorous systematic review of highly cited articles. The articles for this study were extracted from Science Citation Index Expanded (SCI-E), Emerging Sources Citation Index (ESCI), and Social Sciences Citation Index (SSCI) databases of Web of Science Core Collection (WoSCC) covering the period from 2000 to 2020. This study was limited to SCI-E, ESCI, and SSCI databases of the Web of Science. The term “ecosystem service/s” has been used as a research term to filter the study sample and eliminate other databases from the analysis. A citation level equal to or greater than 200 was used to further filtration of articles. This query could restrict to 128 articles that are highly cited in the selected period. Bibliometric analysis results show that, according to the author’s keywords, the “ecosystem service/s” keyword is highly connected to the “biodiversity”, “valuation”, “marine spatial planning”, and “conservation planning”. The U.S.A., Canada, China, France, and Australia are the leading countries in the cumulative number of highly cited articles and networks of co-authors. The U.S.A. is a strong contributor to ES research with China, Canada, and France. The most productive universities linked to the United States were the University of Minnesota, the University of California-Santa Barbara (UC Santa Barbara), and the Chinese Academy of Science. The most significant and compelling author is Halpern S Benjamin, who represents UC Santa Barbara. He has earned international recognition for a model he developed to analyze global data sets of anthropogenic drivers of ecological change in marine environments. The most accessed and studied fields in the ES are terrestrial, urban, and marine environments.

Human cytomegalovirus inhibits erythropoietin production

Anemia is a feature of CKD and a complication of renal transplantation, often caused by impaired production of erythropoietin. The kidney is a target organ for human cytomegalovirus (hCMV) in such patients, but it is not known whether hCMV effects erythropoietin production. We found that kidneys from patients with CKD were positive for hCMV protein and that blood levels of hCMV IgG inversely correlated with red blood cell count. In mice, systemic murine cytomegalovirus infection decreased serum erythropoietin levels. In human erythropoietin-producing cells, hCMV inhibited hypoxia-induced expression of erythropoietin mRNA and protein. hCMV early gene expression was responsible, as ultraviolet-inactivated virus had no effect and valganciclovir treatment showed that late gene expression was nonessential. Hypoxia-induced gene transcription is controlled by the transcription factors hypoxia-inducible transcription factor (HIF)-1α and HIF2α, which are constitutively produced but stable only under low oxygen conditions. We found that hCMV inhibited constitutive production of HIF2α mRNA. HIF2α is thought to be the master regulator of erythropoietin transcription. Single-cell analysis revealed that nuclear accumulation of HIF2α was inhibited in hCMV-infected cells, and the extent of inhibition correlated with hCMV protein expression. Our findings suggest that renal hCMV infection could induce or exacerbate anemia in patients.