The effects of streptokinase in a Chacma baboon (Papio ursinus) model of acquired thrombotic thrombocytopenic purpura

Chacma baboon natural anticoagulants and factor VIII activities

Non-human primates are useful models of human haemostasis, but distinctions do exist. These differences are essential to identify and quantify to better characterise the Chacma baboon's coagulation system.   The Chacma baboon's factor VIII and natural anticoagulants were characterised and compared to human reference ranges. Parameters were measured using commercial chromogenic and clot-based assays, in 40 Rhesus negative, ABO typed, male and female Chacma baboon platelet poor plasma samples. Free protein S concentration, protein C, protein S and factor VIII activity reference intervals revealed important differences, while antithrombin was similar to humans. Between sexes, reference intervals largely overlapped but were wider for free protein S and protein S activity. Factor VIII activity was 14% lower in group O baboons. This research has quantified some of the coagulation similarities and differences between Chacma baboons and humans.

Efficacy analysis of folic acid in chronic atrophic gastritis with Helicobacter pylori infection: a systematic review and meta-analysis

BACKGROUND

Current data indicate that supplements such as folic acid play a significant role in treating chronic atrophic gastritis (CAG). However, no meta-analysis article evaluates its efficacy comprehensively. Therefore, we conducted a meta-analysis to compare the effectiveness and safety of folic acid in the treatment of CAG with Helicobacter pylori (H. pylori) infection.

METHODS

Using a systematic review method, consider randomized controlled trials (RCT), including clinical trial reports, unpublished clinical trial data, and conference papers. A comprehensive search of the literature was conducted from all years up to June 2024. We searched PubMed, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), Vip, and Wanfang databases. Data were extracted using a pre-designed extraction tool and analysis was undertaken using RevMan5.4 and STAT15.1. Efficacy and safety outcomes were evaluated using risk ratio (RR) and 95% confidence intervals (CI).

RESULTS

16 randomized controlled trials with 1364 patients were included. Compared with conventional therapy, folic acid therapy had a higher total effective rate (95.09% vs.79.06%, pooled RR = 1.19, 95% CI: 1.12-1.26, p < 0.00001) and lower incidence of adverse events (11.64% vs. 14.04%, RR = 0.86, 95% CI: 0.46-1.60, p = 0.64). Moreover, folic acid can better improve gastric function and repair gastric mucosa (MD = 27.20, 95%CI:23.84-30.56, p < 0.00001).

CONCLUSIONS

For HP-related CAG, anti-HP treatment and folic acid supplementation should be started as early as possible. Gastric mucosal protective agents can improve the curative effect and can be selected according to the condition of patients with obvious adverse reactions. Our study provided evidence for their potential clinical use in the management of CAG. However, CAG-related studies in other countries and regions need to be further studied.

REGISTRATION

The logn number of our Meta-analysis on PROSPERO is 42,024,571,785.

The thrombin generation capability of the Chacma baboon (Papio ursinus): implications for haemostatic disease models

Baboon models are often used to investigate haemostatic diseases, such as acquired thrombotic thrombocytopenic purpura or bacterial sepsis-induced disseminated intravascular coagulation, and their potential treatment with novel drugs. Thrombin generation is vital for these models, and an important potential therapeutic target. We investigated the thrombin generation profile of the Chacma baboon (Papio ursinus - a common pre-clinical model) including the effects of sex and ABO blood group. Thrombin generation curves, lag times, peak heights, times-to-peak, velocity indexes and Endogenous Thrombin Potentials (ETPs) of 40 adult Chacma baboons were assessed and compared with normal human plasma, using a low concentration of tissue factor (1 pM) and phospholipids. Reference intervals were calculated, and results compared between O and non-O ABO blood groups, and between males and females. Lag times of all baboons fell within the human reference interval. Most animals (n = 32; 80%) had times-to-peak above, and velocity indexes and peak heights markedly below (n = 27; 68%) the human range. However, 97.5% of baboons had an ETP above the human reference interval, indicating greater overall thrombin generation. ABO blood group had no effect, but males (n = 14; 35%) had less potent thrombin generation than females (n = 26; 65%), with significantly longer lag times (p = 0.0475), lower peak thrombin concentrations (p = 0.0203), and lower ETPs (p = 0.0238). Chacma baboons have greater overall endogenous thrombin generation potentials than humans, which is even more prominent in females. This should be considered when designing future baboon model experiments involving the haemostatic system, or when evaluating novel therapies in these animals.