Effect of Activation Methods of Molecular Sieves on Ketimine Synthesis

Although the use of molecular sieves for imine synthesis is a common protocol, there have been no comprehensive studies on heat-drying methods. This can be crucial for reproducibility. It was found that molecular sieve 5A dried at 160 °C for 5 h under vacuum efficiently promoted the condensation of various ketones and amines to afford even relatively bulky ketimines. Several control experiments and analyses revealed that only a small amount of Brønsted acid sites was important for the activity, rather than dehydration ability. Other types of molecular sieves could be utilized for the reaction after treatment with water followed by heat drying. A continuous-flow acetalization reaction of alcohols using the activated molecular sieve 5A was also demonstrated

Effects of Arabidopsis Ku80 deletion on the integration of the left border of T-DNA into plant chromosomal DNA via Agrobacterium tumefaciens

T-DNA integration into plant chromosomal DNA via Agrobacterium tumefaciens can be achieved by exploiting the double-strand break repair system of the host’s DNA. However, the detailed mechanism of T-DNA integration remains unclear. Here, a sequence analysis of the junction sequences of T-DNA and chromosomal DNA was performed to assess the mechanism of T-DNA integration. T-DNA was introduced into Arabidopsis wild-type and NHEJ-deficient ku80-mutant plants using the floral dip method; the junctions of the left border (LB) of T-DNA were subsequently analyzed by adapter PCR. The most frequent junction of the LB of T-DNA to chromosomal DNA (LB-to-ChrDNA) was of the filler DNA type in both lines. The lengths of direct or inverted repeat sequences within or around the filler DNA sequence were longer in the ku80 mutant. In addition, the frequency of T-DNA integration near the transcription start site was significantly higher in the ku80 mutant. Our observations suggest that the presence of the Ku80 protein affects the location of the integration of T-DNA and the pattern of the formation of repeat sequences within or around the filler DNA during LB integration into chromosomal DNA

Changes in glycemic control and skeletal muscle mass indices after dapagliflozin treatment in individuals with type 1 diabetes mellitus

Abstract Aims/Introduction Dapagliflozin is used for individuals with type 1 diabetes, although the effect of this medication on skeletal muscle mass is not well established. In addition, there are few studies examining the effects of good glycemic control on skeletal muscle mass in type 1 diabetes patients. We investigated changes in glycemic control and skeletal muscle mass with dapagliflozin in individuals with type 1 diabetes, and the association between these changes. Materials and Methods This was a post‐hoc analysis of a multicenter, open‐label, non‐randomized, prospective, interventional study in individuals with type 1 diabetes. The participants received dapagliflozin at 5 mg/day for 4 weeks, and were reviewed before and after treatment. Weight‐ and height‐corrected appendicular skeletal muscle mass (ASM) were calculated as indices of skeletal muscle mass using bioelectrical impedance analysis. Results A total of 36 individuals were included in the analysis. After the 4 weeks of dapagliflozin treatment, ASM/height2 decreased in the body mass index 60 years. The change in ASM / weight (%) was negatively correlated with the change in glycated hemoglobin (%;P = 0.023). The change in ASM / height2 (kg/m2) was also positively correlated with the change in time within the glucose range of 70–180 mg/dL (P = 0.036). Conclusion Dapagliflozin treatment of individuals with type 1 diabetes, particularly non‐obese individuals and older men, might result in loss of skeletal muscle mass. However, good glycemic control during treatment might prevent the onset and progression of sarcopenia

Milk protects against sarcopenic obesity due to increase in the genus Akkermansia in faeces of db/db mice

Abstract Background Sarcopenic obesity, a combination of sarcopenia and obesity, is a pathological feature of type 2 diabetes. Several human studies have shown that milk is useful in the prevention of sarcopenia. This study was aimed at clarifying the effect of milk on the prevention of sarcopenic obesity in db/db mice. Methods A randomized and investigator‐blinded study was conducted using male db/db mice. Eight‐week‐old db/db mice were housed for 8 weeks and fed milk (100 μL/day) using a sonde. The faecal microbiota transplantation (FMT) group received antibiotics for 2 weeks, starting at 6 weeks of age, followed by FMT twice a week until 16 weeks of age. Results Milk administration to db/db mice increased grip strength (Milk−: 164.2 ± 4.7 g, Milk+: 230.2 ± 56.0 g, P = 0.017), muscle mass (soleus muscle, Milk−: 164.2 ± 4.7 mg, Milk+: 230.2 ± 56.0 mg, P < 0.001; plantaris muscle, Milk−: 13.3 ± 1.2 mg, Milk+: 16.0 ± 1.7 mg, P < 0.001) and decreased visceral fat mass (Milk−: 2.39 ± 0.08 g, Milk+: 1.98 ± 0.04 mg, P < 0.001), resulting in a significant increase in physical activity (light: P = 0.013, dark: P = 0.034). FMT from mice fed milk not only improved sarcopenic obesity but also significantly improved glucose intolerance. Microarray analysis of gene expression in the small intestine revealed that the expression of amino acid absorption transporter genes, namely, SIc7a5 (P = 0.010), SIc7a1 (P = 0.015), Ppp1r15a (P = 0.041) and SIc7a11 (P = 0.029), was elevated in mice fed milk. In 16S rRNA sequencing of gut microbiota, the genus Akkermansia was increased in both the mice fed milk and the FMT group from the mice fed milk. Conclusions The findings of this study suggest that besides increasing the intake of nutrients, such as amino acids, milk consumption also changes the intestinal environment, which might contribute to the mechanism of milk‐induced improvement of sarcopenic obesity

The Effects of Metformin on the Gut Microbiota of Patients with Type 2 Diabetes: A Two-Center, Quasi-Experimental Study

Metformin is reported to affect human gut microbiota; however, the nature of this association in Japanese patients with type 2 diabetes mellitus (T2DM) is unknown. We enrolled 31 patients with T2DM who took metformin for the first time in this study. We compared them before and after four weeks of taking metformin. Fecal samples were collected and 16S rDNA sequences were performed to identify the gut microbiota. Blood samples and Gastrointestinal Symptom Rating Scale (GSRS) questionnaire results, denoting gastro-intestinal symptoms, were also collected. In the whole-group analysis, no significant differences were found at the phylum level. In a subgroup of 21 patients that excluding those using medications affecting gut microbiota, there was a significant decrease of the phylum Firmicutes (p = 0.042) and of the ratio of the Firmicutes and Bacteroidetes abundances (p = 0.04) after taking metformin. Changes in abdominal pain (r = &minus;0.56, p = 0.008) and regurgitation (r = &minus;0.53, p = 0.01) were associated with Parabacteroides. Despite there being no direct association with abdominal symptoms, our study revealed that the composition of gut microbiota in Japanese individuals with T2DM partially changed after starting metformin

Reasons for Discontinuing Treatment with Sodium-Glucose Cotransporter 2 Inhibitors in Patients with Diabetes in Real-World Settings: The KAMOGAWA-A Study

Sodium-glucose cotransporter 2 inhibitors (SGLT2is) are a class of antidiabetic agents known to exert cardioprotective, renoprotective, and hypoglycemic effects. However, these agents have been associated with adverse effects, such as genital infection, volume depletion, hypoglycemia, and diabetic ketoacidosis, resulting in drug discontinuation. Herein, we aimed to determine the reasons for discontinuing treatment with SGLT2is among Japanese patients with diabetes. This retrospective cohort study enrolled 766 patients with diabetes who had initiated SGLT2is between January 2014 and September 2021. The follow-up period was 2 years from the initiation of the SGLT2is. Overall, 97 patients (12.7%) discontinued the SGLT2is during the follow-up period. The most common reasons for discontinuing the SGLT2is were frequent urination (19.6%), followed by genital infection (11.3%), improved glycemic control (10.6%), and renal dysfunction (8.2%). A comparison of the characteristics between the continuation and the discontinuation group was conducted, excluding those who discontinued the SGLT2is because of improved glycemic control. The patients in the discontinuation group (68 [55–75] years) were older than those in the continuation group (64 [53–71] years; p = 0.003). Importantly, we found no significant association between diabetes duration, diabetic control, renal function, or complications of diabetes in both groups. This real-world study revealed that frequent urination was the most common reason underlying SGLT2i discontinuation among Japanese patients with diabetes. To avoid discontinuation, precautions against various factors that may cause frequent urination must be implemented

Gut Microbiota Changes by an SGLT2 Inhibitor, Luseogliflozin, Alters Metabolites Compared with Those in a Low Carbohydrate Diet in db/db Mice

In recent years, sarcopenic obesity has been considered central pathological factors in diabetes. This study aimed to compare the effect of luseogliflozin, a sodium-glucose co-transporter-2 inhibitor (SGLT2i), on sarcopenic obesity in comparison to that of a low-carbohydrate diet (LCD). Twenty-week-old male db/db mice were fed a normal diet (Ctrl), LCD, and normal diet with 0.01% w/w luseogliflozin (SGLT2i) for eight weeks. Skeletal muscle mass and grip strength decreased in the LCD group mice compared to those in the control group, while they increased in the SGLT2i group mice. The amino acid content in the liver, skeletal muscle, and serum were lower in the LCD group than those in the Ctrl group but increased in the SGLT2i group mice. Short-chain fatty acids in rectal feces were lower in the LCD group mice than those in the Ctrl group, whereas they were higher in the SGLT2i group mice. The abundance of Gammaproteobacteria, Enterobacteriaceae, Escherichia, Enterobacterales, and Bacteroides caccae species increased in the LCD group compared to the other two groups, whereas the abundance of Syntrophothermus lipocalidus, Syntrophomonadaceae family, Parabacteroidesdistasonis distasonis, and the genus Anaerotignum increased in the SGLT2i group. Luseogliflozin could prevent sarcopenic obesity by improving amino acid metabolism