Evaluation of two laboratory model methods for diarrheal irritable bowel syndrome.

BACKGROUND: Diarrheal irritable bowel syndrome (IBS-D) is a common chronic functional gastrointestinal disorder, and the underlying pathogenic mechanism is still unclear. Animal models that mimic the pathological state of IBS-D patients were constructed to provide a reference for later drug research and model development. METHODS: The IBS-D model was induced using restraint stress and chemical stimulation (rhubarb), and rats were divided into normal control group (NC), chemically stimulated group (CS), and restraint stress group (RS). Visceral motility responses to Colorectal Balloon Dilation (CRD) were measured by Abdominal Withdrawal Reflex (AWR); evaluation of faecal properties and water content; determination of colonic tissue tight junction (TJ) mRNA expression by RT-PCR; measurement of inflammatory cytokines by ELISA; and intestinal flora and short chain fatty acids. RESULTS: Compared to NC group, CS and RS group rats showed increased intestinal sensitivity and Bristol stool score, significant diarrheal symptoms and weight loss. Mucin 2, ZO-1, OCLN, CLDN4 mRNA expression was reduced and the intestinal mucosal barrier function was diminished. In addition, the levels of inflammatory factors IL-1ß, IL-6, IL-8, IL-10 and TNF-α increased, the abundance and diversity of intestinal flora decreased, the content of beneficial bacteria such as Bifidobacteria decreased, and SCFAs such as acetic acid, propionic acid and butyric acid decreased to different degrees. Although, no significant difference was observed for any molecular and inflammatory marker, but compared to CS group, RS group had less water in the stool, higher visceral sensitivity, and higher relative abundance of beneficial intestinal bacteria such as Actinobacteria. CONCLUSION: In conclusion, restraint stress combined with chemical stimulation can mimic the pathological state of diarrhoea symptoms, visceral hypersensitivity, reduced intestinal mucosal barrier permeability, immune regulatory dysfunction and dysbiosis in IBS-D patients. However, herbs with antibacterial effects such as rhubarb and senna, for example, are not suitable as the first choice for chemical stimulation, as they may lead to a decrease in harmful bacteria and an increase in beneficial bacteria in the intestinal fraction and do not perfectly mimic the imbalanced state of intestinal flora in IBS-D patients, while restraint stress may be a key factor in modelling.

[Analytical figures of merit of Hildebrand grid and ultrasonic nebulizations in inductively coupled plasma atomic emission].

Hildebrand grid nebulizer is a kind of improved Babington nebulizer, which can nebulize solutions with high total dissolved solids. And the ultrasonic nebulizer (USN) possesses advantage of high nebulization efficiency and fine droplets. In the present paper, the detection limits, matrix effects, ICP robustness and memory effects of Hildebrand grid and ultrasonic nebulizers for ICP-AES were studied. The results show that the detection limits using USN are improved by a factor of 6-23 in comparison to Hildebrand grid nebulizer for Cu, Pb, Zn, Cr, Cd and Ni. With the USN the matrix effects were heavier, and the degree of intensity enhancement and lowering depends on the element line, the composition and concentrations of matrices. Moreover, matrix effects induced by Ca and Mg are more significant than those caused by Na and Mg, and intensities of ionic lines are affected more easily than those of atomic lines. At the same time, with the USN ICP has less robustness. In addition, memory effect of the USN is also heavier than that of Hildebrand grid nebulizer.

Effect of Shenling Baizhu powder on immunity to diarrheal disease: A systematic review and meta-analysis.

Background: Diarrhea is one of the leading causes of death worldwide and is associated with immune dysfunction. The modulatory effects of Shenling Baizhu powder (SLBZS) on immune function in diarrheal disease have been validated in various animal models. However, the results of these studies have not been systematically evaluated. This study aimed to evaluate the preclinical data on SLBZS for the treatment of diarrhea from an immunological perspective. Methods: PubMed, Embase, Cochrane Library, CNKI, Wanfang Database, VIP, and Chinese Medicine Database were searched for all animal trials on SLBZS for the treatment of diarrhea published up to April 2022. Standardized mean differences (SMD) were used as effect sizes in the meta-analysis of continuous variables, including immune organs, immune cells, and immune cytokines. Subgroup analysis was performed according to animal species and disease models. The GRADE was used to assess the quality of evidence. Results: A total of 26 studies were included. Meta-analysis showed that compared to those in the model group, SLBZS significantly increased body weight [SMD = 1.54, 95% confidence interval (CI) (1.06, 2.02)], spleen mass [SMD = 1.42, 95% CI (0.98, 1.87)], thymus mass [SMD = 1.11, 95% CI (0.69, 1.53)], macrophage phagocytic capacity (SMD = 1.07, 95% CI [0.59, 1.54]), sIgA [SMD = 1.04, 95% CI (0.33, 1.74)], RBC-C3b-RR [SMD = 1.16, 95% CI (0.65, 1.67)], IL-2 [SMD = 1.52, 95% CI (0.89, 2.14)] and decreased diarrhea scores [SMD = -1.40, 95% CI (-2.03, -0.87)], RBC-IC-RR [SMD = -1.40, 95% CI (-1.94, -0.87)], and IL-8 [SMD = -2.80, 95% CI (-3.54, -2.07)]. Subgroup analysis showed that SLBZS regulated TNF-α, IL-1ß, and IL-10 in rats and mice, and improved IL-6 and IL-10 in different diseases, with differences between subgroups (p < 0.05). Owing to heterogeneity, the reliability of the results remains to be verified. The quality of evidence was "very low". Conclusion: SLBZS improve diarrhea symptoms by enhancing immune function. It has curative effects with differences between different species and diseases, however, because the reporting in the original studies was too unclear to be assessed, the analysis was inconclusive. For higher quality evidences, future research should pay attention to the scientific rigor of the experimental design and the completeness of the reported results.