In 2018, the World Journal of Gastroenterology (WJG) has published the 4^th issue which containing 10 articles including 1 review, 7 original articles, and 2 case reports contributed by scientists worldwide. Among these comprehensive articles are (1) “Vitamin D deficiency and hepatitis viruses-associated liver diseases: A literature review”, a review by  Thirumalaisamy P Velavan, PhD, Professor, et al from  Molecular Genetics of Infectious Diseases, Institute of Tropical Medicine, University of Tübingen, Germany; (2) “Diet switch and omega-3 hydroxy-fatty acids display differential hepatoprotective effects in an obesity/nonalcoholic fatty liver disease model in mice”, a basic study by  Juan Armendariz-Borunda, PhD, Professor, FAASLD, Head, et al from Institute for Molecular Biology and Gene Therapy CUCS, Department of Molecular Biology and Genomics, University of Guadalajara, Mexico; and (3) “Intraductal papillary bile duct adenocarcinoma and gastrointestinal stromal tumor in a case of neurofibromatosis type 1”, a case report by Jae Min Lee, MD, PhD, Assistant Professor, et al from Division of Gastroenterology and Hepatology, Department of Internal Medicine, Korea University Anam Hospital, South Korea, etc. We invite you to peruse all 10 articles in this issue, as they present the latest research progress/findings and provide insightful comments in gastroenterology and hepatology that will guide basic research and clinical practice in these fields.

This journal is an open-access journal which allows free immediate access to all full-text articles. For details, please visit: Volume 24, Issue 4, January 28, 2018.

Figure 1 The cover of the issue. Editorial board member of World Journal of Gastroenterology, Alisan Kahraman, MD, Associate Professor, Department of Gastroenterology and Hepatology, University Hospital of Essen, Essen, North-Rhine Westphalia 45147, Germany

We encourage gastroenterologists and hepatologists worldwide to submit manuscripts to the WJG describing their original basic or clinical research findings that are of high academic value and which report new diagnostic techniques or summarize their treatment experiences.