Assessment of the quality, diagnosis, and therapeutic recommendations of clinical practice guidelines on patients with Helicobacter pylori infection: A systematic review

We conducted this study to systematically review and assess the current clinical practice guidelines (CPGs) related to the diagnosis and treatment of Helicobacter pylori (H. pylori) infection. The aim was to evaluate the quality of these included CPGs and provide clinicians with a convenient and comprehensive reference for updating their own CPGs. We searched four databases to identify eligible CPGs focusing on H. pylori diagnosis and treatment recommendations. The results were presented using evidence mappings. Quality and clinical applicability were assessed comprehensively using AGREE-II and AGREE-REX. Statistical tests, specifically Bonferroni tests, were employed to compare the quality between evidence-based guidelines and consensus. A total of 30 eligible CPGs were included, comprising 17 consensuses and 13 guidelines. The quality showed no statistical significance between consensuses and guidelines, mainly within the moderate to low range. Notably, recommendations across CPGs exhibited inconsistency. Nevertheless, concerning diagnosis, the urea breath test emerged as the most frequently recommended method for testing H. pylori. Regarding treatment, bismuth quadruple therapy stood out as the predominantly recommended eradication strategy, with high-dose dual therapy being a newly recommended option. Our findings suggest the need for specific organizations to update their CPGs on H. pylori or refer to recently published CPGs. Specifically, CPGs for pediatric cases require improvement and updating, while a notable absence of CPGs for the elderly was observed. Furthermore, there is a pressing need to improve the overall quality of CPGs related to H. pylori. Regarding recommendations, additional evidence is essential to elucidate the relationship between H. pylori infection and other diseases and refine test indications. Clinicians are encouraged to consider bismuth quadruple or high-dose dual therapy, incorporating locally sensitive antibiotics, as empirical radical therapy. .

Antibiotics Resistance Prevalence of Helicobacter pylori Strains in Northwest China

Purpose

This study aims to estimate the resistance rate of Helicobacter pylori (HP) to commonly used antibiotics and analyze the potential influencing factors in northwest regions of China.

Patients and Methods

HP-positive patients visiting the outpatient department of multiple hospitals were enrolled in the study. Then, gastric mucosal biopsy specimens were collected for HP isolation, culture, and investigation of the resistance rate of HP to amoxicillin, metronidazole, tetracycline, levofloxacin, and clarithromycin by Epsilometer test (E-test) antibiotic susceptibility testing. In addition, multi-drug resistance, the influence of HP eradication history, age, and region of residence on drug resistance rate were analyzed.

Results

In total, 198 HP clinical strains were successfully isolated and cultured. The resistance rates of amoxicillin, metronidazole, tetracycline, levofloxacin, and clarithromycin were 16.16%, 85.86%, 7.58%, 46.46%, and 55.05%, respectively. The multi-drug resistance rates demonstrated that dual and triple resistances were 30.30% and 22.73%, respectively. The quadruple resistance rate reached 9.60%. Our results revealed that the prior eradication history of HP significantly increased levofloxacin and clarithromycin resistance. Metronidazole and levofloxacin resistances significantly differed among different age groups, which presented an upward trend with increasing age. Drug resistance rates varied with geographic regions, especially amoxicillin and clarithromycin resistance, which were highest in Hexi Corridor and Longnan regions.

Conclusion

The current situation of HP resistance to common antibiotics is severe. Tetracycline is the most sensitive antibiotic, followed by amoxicillin, the first choice for HP eradication. However, the eradication failure of HP may lead to an increase in the resistance rate. Therefore, it is necessary to strengthen the standardized diagnosis and treatment of HP to improve the primary eradication rate.

Platelet-rich plasma and regenerative dentistry

Regenerative dentistry is an emerging field of medicine involving stem cell technology, tissue engineering and dental science. It exploits biological mechanisms to regenerate damaged oral tissues and restore their functions. Platelet‐rich plasma (PRP) is a biological product that is defined as the portion of plasma fraction of autologous blood with a platelet concentration above that of the original whole blood. A super‐mixture of key cytokines and growth factors is present in platelet granules. Thus, the application of PRP has gained unprecedented attention in regenerative medicine. The rationale underlies the utilization of PRP is that it acts as a biomaterial to deliver critical growth factors and cytokines from platelet granules to the targeted area, thus promoting regeneration in a variety of tissues. Based on enhanced understanding of cell signalling and growth factor biology, researchers have begun to use PRP treatment as a novel method to regenerate damaged tissues, including liver, bone, cartilage, tendon and dental pulp. To enable better understanding of the regenerative effects of PRP in dentistry, this review describes different methods of preparation and application of this biological product, and provides detailed explanations of the controversies and future prospects related to the use of PRP in dental regenerative medicine.

Phenotypic variation and diversity of Magnolia sprengeri Pamp. in native habitat

The population of Magnolia sprengeri individuals deceased drastically in the late 20th century because of the widespread harvest for traditional Chinese medicinal recipes. In this study, the levels of phenotypic variation and the genetic structure of 2 populations of M. sprengeri were estimated. The phenotypic variation of M. sprengeri characteristics was nonsynchronous, with a coefficient of variation for 37 characters from 9.55-35.87%. The variance stabilizing transformation value ranged from 0.034-52.344%. The variation contribution within the population was greater than the contribution among the population; the among-population rate was 2.864%, while the within-population rate was 15.849%; values of repeatability for among-population and within-population were 0.430 and 0.098, respectively. This indicates that more variation arose from within-population and that population repeatability was much greater than individual repeatability. Variation in the flower organ was greater than that in the leaf organ; this means that vegetative variation was more stable than reproductive variation. Variation in the southern population was greater than that in the northern population.

Protective effect of the nitric oxide pathway in L-citrulline renal ischaemia-reperfusion injury in rats

To observe the protective effects of L-citrulline on the renal I/R injury and elucidate the mechanisms involved, 48 rats were randomized into eight groups: Group 1: sham operated; Group 2: I/R (45 min renal ischaemia and 24 h reperfusion); Group 3: I/R + L-citrulline (300 mg/kg, i.g.); Group 4: I/R + L-citrulline (600 mg/kg, i.g.); Group 5: I/R + L-citrulline (900 mg/kg, i.g.); Group 6: I/R + normal saline (NS, i.g.); Group 7: I/R + N sup ω nitro-L-arginine ester (L-NAME, 20 mg/kg, i.p.); Group 8: I/R + L-citrulline (900 mg/kg, i.g.) + L-NAME (20 mg/ kg, i.p.). At the end of the reperfusion period, serum was collected and the kidneys underwent histological and biochemical examinations. Our results showed that pre-treatment with L-citrulline (300, 600, and 900 mg/kg) significantly ameliorated the renal injury caused by I/R. Moreover, L-citrulline prevented induction of lipid peroxidation and increased the activity of superoxide dismutase and the levels of glutathione and nitric oxide. The I/R-induced decreases in total nitric oxide synthase activity, inducible nitric oxide activity, constitutive nitric oxide activity and endothelial nitric oxide protein expression in the renal cortex were significantly prevented. However, the L-citrulline-mediated protection was significantly antagonized by co-administration of L-NAME. These results suggested that L-citrulline administration exhibited significant protection against renal I/R injury. This protective effect, at least in part, via up-regulation of the endothelial nitric oxide protein expression and constitutive nitric oxide synthase activity, maintained production of nitric oxide at the basal level.

Prokaryotic expression of a novel mouse pro-apoptosis protein PNAS-4 and application of its polyclonal antibodies

Mouse PNAS-4 (mPNAS-4) has 96% identity with human PNAS-4 (hPNAS-4) in primary sequence and has been reported to be involved in the apoptotic response to DNA damage. However, there have been no studies reported of the biological functions of mPNAS-4. In studies conducted by our group (unpublished data), it was interesting to note that overexpression of mPNAS-4 promoted apoptotic death in Lewis lung carcinoma cells (LL2) and colon carcinoma cells (CT26) of mice both in vitro and in vivo. In our studies, mPNAS-4 was cloned into the pGEX-6P-1 vector with GST tag at N-terminal in Escherichia coli strain BL21(DE3). The soluble and insoluble expression of recombinant protein mPNAS-4 (rmPNAS-4) was temperature-dependent. The majority of rmPNAS-4 was insoluble at 37 degrees C, while it was almost exclusively expressed in soluble form at 20 degrees C. The soluble rmPNAS-4 was purified by one-step affinity purification, using a glutathione Sepharose 4B column. The rmPNAS-4 protein was further identified by electrospray ionization-mass spectrometry analysis. The search parameters of the parent and fragment mass error tolerance were set at 0.1 and 0.05 kDa, respectively, and the sequence coverage of search result was 28%. The purified rmPNAS-4 was further used as immunogen to raise polyclonal antibodies in New Zealand white rabbit, which were suitable to detect both the recombinant and the endogenous mPNAS-4 in mouse brain tissue and LL2 cells after immunoblotting and/or immunostaining. The purified rmPNAS-4 and our prepared anti-mPNAS-4 polyclonal antibodies may provide useful tools for future biological function studies for mPNAS.