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Background: Evidence suggests that type 2 diabetes (T2D) is an independent risk factor for Alzheimer's disease (AD), sharing similar pathophysiological traits like impaired insulin signaling. Objective: To test the association between plasma insulin and cerebrospinal fluid (CSF) AD pathology. Methods: A total of 304 participants were included in the Alzheimer's Disease Neuroimaging Initiative, assessing plasma insulin and CSF AD pathology. We explored the cross-sectional and longitudinal associations between plasma insulin and AD pathology and compared their associations across different AD clinical and pathological stages. Results: In the non-demented group, amyloid-β (Aβ)+ participants (e.g., as reflected by CSF Aβ42) exhibited significantly lower plasma insulin levels compared to non-demented Aβ–participants (p < 0.001). This reduction in plasma insulin was more evident in the A+T+ group (as shown by CSF Aβ42 and pTau181 levels) when compared to the A–T– group within the non-dementia group (p = 0.002). Additionally, higher plasma insulin levels were consistently associated with more normal CSF Aβ42 levels (p < 0.001) across all participants. This association was particularly significant in the Aβ–group (p = 0.002) and among non-demented individuals (p < 0.001). Notably, baseline plasma insulin was significantly correlated with longitudinal changes in CSF Aβ42 (p = 0.006), whereas baseline CSF Aβ42 did not show a similar correlation with changes in plasma insulin over time. Conclusions: These findings suggest an association between plasma insulin and early Aβ pathology in the early stages of AD, indicating that plasma insulin may be a potential predictor of changes in early Aβ pathology. [ABSTRACT FROM AUTHOR]

Objective:To study the preventive effect of fucoidan on non-alcoholic fatty liver disease induced by high fat diet. Methods: The experimental mice were randomly divided into three groups: control group, high-fat diet group and fucoidan intervention group. The control group was fed a standard diet, and the other two groups were fed a high-fat diet. The control group and the high-fat diet group were given normal saline intragastric administration every day, and the intervention group was given intragastric administration of fucoidan polysaccharide solution at a dose of 100 mg·kg-1·d-1 once a day for continuous intervention for 12 weeks. After the last intragastric administration for 12 h, the body weight and liver weight of each group of mice were measured, and the liver index was calculated. The contents of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total cholesterol (TC) and triglyceride (TG) in liver tissues of mice in each group were detected by biochemical kit. Hematoxylin-eosin staining (HE) was used to compare the pathological morphological changes of liver tissue in each group. The contents of inflammatory factor interleukin-6 (IL-6), tumor necrosis factor (TNF-α) and oxidative stress index malondialdehyde (MDA), and the activities of glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) in liver tissues of mice in each group were determined. Results: Compared with the control group, the body weight and liver index of mice receiving high fat diet increased significantly (P<0.01). In addition, the contents of TG, TC, AST and ALT in liver tissue of high-fat diet group were significantly increased compared with that of control group (P<0.01). The liver tissue of mice in the high-fat diet group also showed significant pathological changes, accompanied by increased expression of inflammatory factors and a significant increase in oxidative stress response. However, compared with the mice in the high-fat diet group, the above indexes were significantly improved in the liver tissue of the mice treated with fucoidan (P<0.01). Conclusion: Fucoidan can inhibit liver lipid deposition, liver inflammation and oxidative stress induced by high fat diet. [ABSTRACT FROM AUTHOR]

Endonuclease IV (EndoIV) is a DNA damage-specific endonuclease that mainly hydrolyzes the phosphodiester bond located at 5′ of an apurinic/apyrimidinic (AP) site in DNA. EndoIV also possesses 3′-exonuclease activity for removing 3′-blocking groups and normal nucleotides. Here, we report that Thermococcus eurythermalis EndoIV (TeuendoIV) shows AP endonuclease and 3′-exonuclease activities. The effect of AP site structures, positions and clustered patterns on the activity was characterized. The AP endonuclease activity of TeuendoIV can incise DNA 5′ to various AP site analogues, including the alkane chain Spacer and polyethylene glycol Spacer. However, the short Spacer C2 strongly inhibits the AP endonuclease activity. The kinetic parameters also support its preference to various AP site analogues. In addition, the efficient cleavage at AP sites requires ≥2 normal nucleotides existing at the 5′-terminus. The 3′-exonuclease activity of TeuendoIV can remove one or more consecutive AP sites at the 3′-terminus. Mutations on the residues for substrate recognition show that binding AP site-containing or complementary strand plays a key role for the hydrolysis of phosphodiester bonds. Our results provide a comprehensive biochemical characterization of the cleavage/removal of AP site analogues and some insight for repairing AP sites in hyperthermophile cells. [ABSTRACT FROM AUTHOR]

Single nucleotide polymorphism (SNP), as one of the key components of the genetic factors, is important for disease detection and early screening of hereditary diseases. Current SNP genotyping methods require laboratory instruments or long operating times. To facilitate the diagnosis of hereditary diseases, we developed a new method referred to as the LwaCas13a-based SNP genotyping platform (Cas13a platform), which is useful for detecting disease-related SNPs. We report a CRISPR/Cas13a-based SNP genotyping platform that couples recombinase-aided amplification (RAA), T7 transcription, and Leptotrichia wadei Cas13a (LwaCas13a) detection for simple and fast genotyping of human disease-related SNPs. We used this Cas13a platform to identify 17 disease-related SNPs, demonstrating that position 2 in gRNA is suitable for the introduction of additional mismatches to achieve high discrimination in genotyping across a wide range of SNP targets. The discrimination specificity of 17 SNPs was improved 3.0-35.1-fold after introducing additional mismatches at position 2 from the 5'-end. We developed a method, which has a lower risk of cross-contamination and operational complexity, for genotyping SNPs using human saliva samples in an one-pot testing that delivers results within 60 min. Compared to TaqMan probe qPCR, RFLP, AS-PCR and other SNP genotyping methods, the Cas13a platform is simple, rapid and reliable, expanding the applications of the CRISPR/Cas system in nucleic acid detection and SNP genotyping., (Copyright © 2024. Published by Elsevier B.V.)

Purpose: To analyze the nutritional status of patients with malignant oral and maxillofacial neoplasms complicated with diabetes mellitus during perioperative period., Methods: Sixty-four patients with malignant oral and maxillofacial neoplasms complicated with diabetes mellitus were collected. Fasting venous blood of patients was extracted on the morning of the day before surgery and then at the 1st, 3rd and 7th day after surgery, respectively. The hemoglobin (Hb), total protein (TP), pre-albumin (PA), lymphocyte count (L), creatinine (Scr), uric acid (UA), urea nitrogen (BUN), glomerular filtration rate (EGFR&#95;EPI&#95;C), white blood cells (WBC) of the patients were detected. The intake of enteral nutrition on the 7th day after operation was investigated. The correlation between nutritional status and the length of stay was analyzed. SPSS 23.0 software package was used for statistical analysis., Results: Compared with the indicators before surgery, the values of TP, ALB, PA, Hb were decreased significantly after surgery in all groups(P<0.05). The level of TP on postoperative day 7 was significantly higher than that on postoperative day 1 and postoperative day 3(P<0.05). The PA level on the third day after surgery was significantly lower than that on the first day after surgery(P<0.05). The Hb level on the 7th and 3rd day after surgery was significantly lower than that on the 1st day after surgery (P<0.05). The level of L decreased significantly in each group after surgery compared with the level before surgery(P<0.05), and gradually increased in each group after surgery, with significant difference among each two groups (P<0.05). Compared with preoperative value, blood Scr was significantly decreased in all groups after surgery (P<0.05), the UA level after surgery was significantly lower than the preoperative level in all groups(P<0.05), and at the 3rd day after surgery was significantly lower than at the 1st day after surgery(P<0.05). After surgery, the eGFR&#95;EPI&#95;c level was significantly higher than the level before surgery in all groups (P<0.05), and at the 7th day after surgery was significantly higher than at the 1st day after surgery (P<0.05). The level of WBC in all patients after surgery was significantly higher than that before surgery(P<0.05), and the level at the 3rd and 7th day after surgery was significantly higher than that at the 1st day after surgery(P<0.05). At the 7th day after surgery, the energy and protein intakes of the patients were significantly lower than the recommendations. There was positive correlation between preoperative BMI and TP, ALB levels at the 1st postoperative day and the TP level at 3rd postoperative day(P<0.05). There was no direct correlation between preoperative BMI and the length of postoperative hospital stay (P>0.05). The length of postoperative hospital stay was negatively correlated with the age and negatively with TP and ALB levels at the 1st postoperative day(P<0.05)., Conclusions: Early postoperative nutritional status of patients with malignant oral and maxillofacial neoplasms complicated with diabetes mellitus decreased significantly. The energy and protein intakes of the patients are significantly lower than the recommendations. The length of postoperative hospital stay is negatively correlated with early postoperative nutritional status and age.

With the development of functional genomics, gene-knockout is becoming an important tool to elucidate gene functions in vivo. As a good model strain for archaeal genetics, Haloferax volcanii has received more attention. Although several genetic manipulation systems have been developed for some halophilic archaea, it is time-consuming because of the low percentage of positive clones during the second-recombination selection. These classical gene knockout methods are based on DNA recombination between the genomic homologous sequence and the circular suicide plasmid, which carries a pyrE selection marker and two DNA fragments homologous to the upstream and downstream fragments of the target gene. Many wild-type clones are obtained through a reverse recombination between the plasmid and genome in the classic gene knockout method. Therefore, it is necessary to develop an efficient gene knockout system to increase the positive clone percentage. Here we report an improved gene knockout method using a linear DNA cassette consisting of upstream and downstream homologous fragments, and the pyrE marker. Gene deletions were subsequently detected by colony PCR analysis. We determined the efficiency of our knockout method by deleting the xpb2 gene from the H. volcanii genome, with the percentage of positive clones higher than 50%. Our method provides an efficient gene knockout strategy for halophilic archaea.

Attempts to transform Klebsiella pneumoniae resulted in very low efficiencies because of capsule polysaccharide (CPS). It was reported that some chelating agents could reduce CPS production and improve transformation efficiency. These methods mentioned above could not improve transformation efficiency apparently by incorporating such agents to liquid medium. However, this method introduces a simple way for efficient transformation of K. pneumoniae. In this method, K. pneumoniae strains NTUH-K2044 and magA(-) mutant are envolved as recipients. The plasmids used in this way are composed of pIP843T, pIP843TdhaB, pIP843TdhaT with different sizes. The sole critical step is to harvest bacteria on LB plates to prepare competent cells. 150 +/- 10, 1.3 x 10(3) +/- 100, 2 x 10(5) +/- 300, and 3.4 x 10(7) +/- 500 transformants were obtained per microgram plasmid DNA with NTUH-K2044 liquid cells, magA(-) liquid cells, NTUH-K2044 solid cells, and magA(-) solid cells, respectively. The number of transformants per microg DNA obtained by electroplating solid cells is at least 10(3) fold higher than that of transformants with liquid-cultured bacteria. This method will benefit gene manipulation and genetic study in K. pneumoniae.