Malnutrition is very common in patients with chronic kidney disease, especially in those on maintenance dialysis. Malnutrition is one of the major factors affecting survival and death of dialysis patients, and reducing their activity tolerance and immunity. There are numerous and interacting risk factors for malnutrition, such as reduced nutritional intake, increased energy expenditure, hormonal disorders, and inflammation. Selenium, in the form of selenoproteins, is involved in many physiological processes in the body and plays an important role in maintaining redox homeostasis. Oxidative stress and infection are very common in dialysis patients, and selenium levels in dialysis patients are significantly lower than those in the healthy population. It has been shown that there is a correlation between selenium levels in hemodialysis patients and their nutrition-related indicators, and that selenium supplementation may improve malnutrition in patients. However, further studies are needed to support this conclusion and there is a lack of basic research to further characterize the potential mechanisms by which selenium may improve malnutrition in dialysis patients. The purpose of this review is to provide a comprehensive overview of factors associated with malnutrition in dialysis patients and to describe the progress of research on nutritional status and selenium levels in dialysis patients.

Introduction: Complete laparoscopic radical resection of colorectal cancer without incision anastomosis is performed by means of natural orifice specimen extraction (NOSE), which avoids a large abdominal wall incision. Although this procedure is increasingly practiced, it is still underdeveloped, one reason being that controversy still exists regarding bacteriological and oncological safety. Aim: To demonstrate the safety of complete laparoscopic radical resection of colorectal cancer without incision anastomosis in bacteriology and oncology.Material and methods: This study was a retrospective study with prospectively collected data. This study continuously collected 420 patients who underwent colorectal cancer surgery in our hospital from January 2018 to March 2022. According to the different surgical methods, they were divided into the NOSE group (the natural orifice specimen extraction group) and the N-NOSE group (specimen removed through abdominal wall auxiliary incision). The two groups were matched 1 : 1 using the propensity score matching (PSM) method to balance at baseline. Bacteriological and oncological outcomes, short-term complications, and long-term prognosis were compared between the two groups.Results: One hundred and eighty-four of the 420 included patients were successfully matched. The differences in gender, body mass index, T stage, N stage, and diabetes status between the two groups after matching were not statistically significant. There were no significant differences in oncological outcomes, short-term complications, and 2-year postoperative disease-free survival between the two groups. There was no significant correlation between positive bacterial culture results and intra-abdominal infection. Conclusions: Compared with traditional laparoscopic surgery, complete laparoscopic radical resection of colorectal cancer without incision anastomosis has satisfactory bacteriological and oncological effects and is worthy of further clinical promotion.