Immune checkpoint blockade (ICB) has demonstrated curative potential in several types of cancer, but only for a small number of patients. Thus, the identification of reliable and noninvasive biomarkers for predicting ICB responsiveness is an urgent unmet need. Here, we show that ICB increased tumor vessel perfusion in treatment-sensitive EO771 and MMTV-PyVT breast tumor as well as CT26 and MCA38 colon tumor models, but not in treatment-resistant MCaP0008 and 4T1 breast tumor models. In the sensitive tumor models, the ability of anti–cytotoxic T lymphocyte–associated protein 4 or anti–programmed cell death 1 therapy to increase vessel perfusion strongly correlated with its antitumor efficacy. Moreover, globally enhanced tumor vessel perfusion could be detected by Doppler ultrasonography before changes in tumor size, which predicted final therapeutic efficacy with more than 90% sensitivity and specificity. Mechanistically, CD8⁺ T cell depletion, IFN-γ neutralization, or implantation of tumors in IFN-γ receptor knockout mice abrogated the vessel perfusion enhancement and antitumor effects of ICB. These results demonstrated that ICB increased vessel perfusion by promoting CD8⁺ T cell accumulation and IFN-γ production, indicating that increased vessel perfusion reflects the successful activation of antitumor T cell immunity by ICB. Our findings suggest that vessel perfusion can be used as a novel noninvasive indicator for predicting ICB responsiveness.

Background: The increasing prevalence of diabetes in the United Kingdom and worldwide calls for new approaches to its management, and diets with low glycaemic index have been proposed as a useful means for managing glucose response. However, there are conflicting reports and differences in the results of studies in terms of their effectiveness. Furthermore, the impact of low-glycaemic index diets and their long-term use in patients with type 2 diabetes remains unclear. Objectives: The objective of this study was to conduct a systematic review and meta-analysis of the effect of low-glycaemic index diets in patients with type 2 diabetes. Methods: Search methods: Randomised controlled studies were selected from a number of databases (EBSCOHost with links to Health Research databases, PubMed, and grey literature) based on the Population, Intervention, Comparator, Outcomes and Study designs (PICOS) framework. The search terms included synonyms and Medical Subject Headings (MeSH) and involved the use of Boolean operators (AND/OR) which allowed the combination of words and search terms. Selection criteria: As per the selection criteria, the following types of articles were selected: studies on randomised controlled trials, with year of publication between 2008 and 2018, including patients with type 2 diabetes. Thus, studies involving patients with gestational and type 1 diabetes were excluded, as were observational studies. Nine articles which met the inclusion criteria were selected for the systematic review, whereas only six articles which met the criteria were included in the meta-analysis. Data collection and analysis: Studies were evaluated for quality and risk of bias. In addition, heterogeneity, meta-analysis, and sensitivity tests of the extracted data were carried out using Review Manager 5.3 (Review Manager, 2014). Results: The findings of the systematic review showed that the low-glycaemic index (low-GI) diet resulted in a significant improvement ( 0.05) in four studies compared with the control diet. Four studies showed improvements in fasting blood glucose in low-GI diets compared to higher-GI diets or control: low-GI diet = 150.8 ± 8.7 vs. higher-GI diet = 157.8 ± 10.4 mg/dL, mean ± SD p = 0.43; low-GI diet = 127.7 vs. high-cereal fibre diet = 136.8 mg/dL, p = 0.02; low-GI diet = 6.5 (5.6–8.4) vs. standard diabetic diet = 6.7 (6.1–7.5) mmol/L, median and interquartile range p > 0.05; and low-GI diet = 7.3 ± 0.3 vs. conventional carbohydrate exchange diet = 7.7 ± 0.4 mmol/L, mean ± SEM (Standard Error of Mean) p < 0.05. The results of the meta-analysis and sensitivity tests demonstrated significant differences (p < 0.001 and p < 0.001, respectively) between the low-GI diet and the higher-GI diet or control diet in relation to glycated haemoglobin. Differences between the low-GI diet and higher-GI diet or control were significant (p < 0.05) with respect to the fasting blood glucose following meta-analysis. Conclusion: The low-GI diet is more effective in controlling glycated haemoglobin and fasting blood glucose compared with a higher-GI diet or control in patients with type 2 diabetes.

Background: Alow carbohydrate diet (LCD) is more beneficial for the glycometabolism in type 2 diabetes (T2DM) and may be effective in reducing depression. Almond, which is a common nut, has been shown to effectively improve hyperglycemia and depression symptoms. This study aimed to determine the effect of an almond-based LCD (a-LCD) on depression and glycometabolism, as well as gut microbiota and fasting glucagon-like peptide 1 (GLP-1) in patients with T2DM. Methods: This was a randomized controlled trial which compared an a-LCD with a low-fat diet (LFD). Forty-five participants with T2DM at a diabetes club and the Endocrine Division of the First and Second Affiliated Hospital of Soochow University between December 2018 to December 2019 completed each dietary intervention for 3 months, including 22 in the a-LCD group and 23 in the LFD group. The indicators for depression and biochemical indicators including glycosylated hemoglobin (HbA1c), gut microbiota, and GLP-1 concentration were assessed at the baseline and third month and compared between the two groups. Results: A-LCD significantly improved depression and HbA1c (p < 0.01). Meanwhile, a-LCD significantly increased the short chain fatty acid (SCFAs)-producing bacteria Roseburia, Ruminococcus and Eubacterium. The GLP-1 concentration in the a-LCD group was higher than that in the LFD group (p < 0.05). Conclusions: A-LCD could exert a beneficial effect on depression and glycometabolism in patients with T2DM. We speculate that the role of a-LCD in improving depression in patients with T2DM may be associated with it stimulating the growth of SCFAs-producing bacteria, increasing SCFAs production and GPR43 activation, and further maintaining GLP-1 secretion. In future studies, the SCFAs and GPR43 activation should be further examined.

Background: The prevalence of type 2 diabetes is on the increase worldwide, and it represents about 90% of adults who are diagnosed with diabetes. Overweight and obesity, lifestyle, genetic predisposition and gut microbiota dysbiosis have been implicated as possible risk factors in the development of type 2 diabetes. In particular, low intake of dietary fibre and consumption of foods high in fat and sugar, which are common in western lifestyle, have been reported to contribute to the depletion of specific bacterial taxa. Therefore, it is possible that intake of high dietary fibre may alter the environment in the gut and provide the needed substrate for microbial bloom. Aim: The current review is a systematic review and meta-analysis which evaluated the role of dietary fibre in modulating gut microbiota dysbiosis in patients with type 2 diabetes. Methods: This is a systematic review and meta-analysis of randomised controlled trials which relied on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) framework. Electronic searches were conducted using EBSCOHost with links to Health Sciences Research Databases, EMBASE and Google Scholar. The reference lists of articles were also searched for relevant studies. Searches were conducted from date of commencement of the database to 5 August 2020. The search strategy was based on the Population, Intervention, Comparator, Outcomes, Studies (PICOS) framework and involved the use of synonyms and medical subject headings (MesH). Search terms were combined with Boolean operators (OR/AND). Results: Nine studies which met the inclusion criteria were selected for the systematic review and meta-analysis, and four distinct areas were identified: the effect of dietary fibre on gut microbiota; the role of dietary fibre on short-chain fatty acids (SCFAs); glycaemic control; and adverse events. There was significant difference (p < 0.01) in the relative abundance of Bifidobacterium with a mean difference of 0.72 (95% CI, 0.56, 0.89) between the dietary fibre group compared with placebo. In relation to the meta-analysis for SCFAs, while there was significant difference (p = 0.02) between the dietary fibre group and placebo with a standardised mean difference of 0.5 (95% CI, 0.08, 0.91) regarding total SCFAs, the differences were not significant (p > 0.05) in relation to acetic acid, propionic acid and butyric acid. There was only significant improvement (p = 0.002) with respect to glycated haemoglobin with a mean difference of −0.18 (95% CI, −0.29, −0.06) between the dietary fibre group and placebo group. Differences between the two groups were not significant (p > 0.05) in relation to fasting blood glucose and homeostatic model assessment of insulin resistance (HOMA-IR). Furthermore, there were no significant differences between the two groups in subjects who reported adverse events. It is possible that the promotion of SCFA producers in greater diversity and abundance by dietary fibre in this review led to improvement in glycated haemoglobin, partly due to increased glucagon-like peptide-1 (GLP-1) production. In addition, Bifidobacterium lactis has been reported to increase glycogen synthesis, decrease expression of hepatic gluconeogenesis genes, improve translocation of glucose transport-4 and promote glucose uptake. It is also possible that the reduction in body weight of participants in the intervention group compared with control may have contributed to the observed improvement in glycated haemoglobin. Conclusion: This systematic review and meta-analysis have demonstrated that dietary fibre can significantly improve (p < 0.05) the relative abundance of Bifidobacterium, total SCFAs and glycated haemoglobin. However, dietary fibre did not appear to have significant effect (p > 0.05) on fasting blood glucose, HOMA-IR, acetic acid, propionic acid, butyric acid and adverse events.

Objective: In China, a low-fat diet (LFD) is mainly recommended to help improve blood glucose levels in patients with type 2 diabetes mellitus (T2DM). However, a low-carbohydrate diet (LCD) has been shown to be effective in improving blood glucose levels in America and England. A few studies, primarily randomized controlled trials, have been reported in China as well. Method: Firstly, we designed two ‘six-point formula’ methods, which met the requirements of LCD and LFD, respectively. Fifty-six T2DM patients were recruited and randomly allocated to the LCD group (n = 28) and the LFD group (n = 28). The LCD group received education about LCD’s six-point formula, while the LFD group received education about LFD’s six-point formula. The follow-up time was three months. The indicators for glycemic control and other metabolic parameters were collected and compared between the two groups. Results: Forty-nine patients completed the study. The proportions of calories from three macronutrients the patients consumed met the requirements of LCD and LFD. Compared to the LFD group, there was a greater decrease in HbA1c level in the LCD group (−0.63% vs. −0.31%, p < 0.05). The dosages of insulin and fasting blood glucoses (FBG) in the third month were lower than those at baseline in both groups. Compared with baseline values, body mass index (BMI) and total cholesterol (TC) in the LCD group were significantly reduced in the third month (p < 0.05); however, there were no statistically significant differences in the LFD group. Conclusions: LCD can improve blood glucose more than LFD in Chinese patients with T2DM. It can also regulate blood lipid, reduce BMI, and decrease insulin dose in patients with T2DM. In addition, the six-point formula is feasible, easily operable, and a practical educational diet for Chinese patients with T2DM.

Patients with functional gastrointestinal tract who are unable to meet their nutritional requirements may benefit from the use of enteral nutrition via feeding tubes which could be nasogastric, percutaneous endoscopic gastrostomy and jejunostomy. Although enteral tube feeding has been shown to promote nutritional status, improve wound healing, and enhance patients’ quality of life (QoL), evidence of tube and feed complications and reduced QoL has also been reported. Despite the increasing prevalence of patients on enteral tube feeding, no systematic review examining the role of enteral tube feeding on patients’ QoL appears to have been published. Aim: The aim of this systematic review is to evaluate the effect of enteral tube feeding on patients’ QoL. Method: Three databases (EMBASE, Pubmed, and PsycINFO) plus Google Scholar were searched for relevant articles based on the Population, Intervention, Comparator, Outcomes (PICO) framework. The review was in line with preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines and involved the use of synonyms and medical subject headings. In addition, search terms were combined using Boolean operators (AND/OR) and all the articles retrieved were exported to EndNote for de-duplication. Results: Fourteen articles which met the criteria were included and three distinct areas were identified: the effect of early versus late enteral tube feeding on QoL; the QoL of patients on gastrostomy versus standard care, and the effect of enteral tube feeding on QoL. Overall, nine studies reported improvement in the QoL of patients on enteral tube feeding, while five studies demonstrated either no significant difference or reduction in QoL. Some factors which may have influenced these outcomes are differences in types of gastrostomy tubes, enteral feeding methods (including time patients spent connected to enteral feed/pump), and patients’ medical conditions, as well as the generic and/or type of QoL measuring instrument used. Conclusion: Most reviewed studies suggest that enteral tube feeding is effective in improving patients’ QoL. The use of enteral tube feeding-specific QoL measuring instruments is recommended for future research, and improved management strategies including use of mobile enteral feeding pumps should further enhance patients’ QoL. More studies on the effect of delivery systems/enteral feeding pumps on QoL are needed as research in this area is limited.